por First Death Tied to Lung Injury From Vaping Reported in Illinois By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: First Death Tied to Lung Injury From Vaping Reported in IllinoisCategory: Health NewsCreated: 8/23/2019 12:00:00 AMLast Editorial Review: 8/26/2019 12:00:00 AM Full Article
por Every Sudden Infant Death Deserves a Closer Look: Report By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Every Sudden Infant Death Deserves a Closer Look: ReportCategory: Health NewsCreated: 8/26/2019 12:00:00 AMLast Editorial Review: 8/27/2019 12:00:00 AM Full Article
por Confirmed Case of Coronavirus Reinfection Reported By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Confirmed Case of Coronavirus Reinfection ReportedCategory: Health NewsCreated: 8/25/2020 12:00:00 AMLast Editorial Review: 8/25/2020 12:00:00 AM Full Article
por There's No Safe Amount of Caffeine in Pregnancy: Report By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: There's No Safe Amount of Caffeine in Pregnancy: ReportCategory: Health NewsCreated: 8/24/2020 12:00:00 AMLast Editorial Review: 8/25/2020 12:00:00 AM Full Article
por Olympian Usain Bolt Reported to Have COVID-19 By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Olympian Usain Bolt Reported to Have COVID-19Category: Health NewsCreated: 8/25/2020 12:00:00 AMLast Editorial Review: 8/26/2020 12:00:00 AM Full Article
por Hospitals Must Report COVID-19 Data or Be Penalized By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Hospitals Must Report COVID-19 Data or Be PenalizedCategory: Health NewsCreated: 8/28/2020 12:00:00 AMLast Editorial Review: 8/28/2020 12:00:00 AM Full Article
por Parents' Poll Finds Strong Support for Vaccination of Students, Teachers By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Parents' Poll Finds Strong Support for Vaccination of Students, TeachersCategory: Health NewsCreated: 8/23/2021 12:00:00 AMLast Editorial Review: 8/23/2021 12:00:00 AM Full Article
por AHA News: Native People Find Support, 'Sacred Space' Through This Nonprofit's Work By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: AHA News: Native People Find Support, 'Sacred Space' Through This Nonprofit's WorkCategory: Health NewsCreated: 8/23/2021 12:00:00 AMLast Editorial Review: 8/24/2021 12:00:00 AM Full Article
por One Activity Causes 4 Out of 5 Sports-Linked Spinal Injuries By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: One Activity Causes 4 Out of 5 Sports-Linked Spinal InjuriesCategory: Health NewsCreated: 8/25/2021 12:00:00 AMLast Editorial Review: 8/25/2021 12:00:00 AM Full Article
por Record High COVID Cases and Deaths Reported in Florida By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Record High COVID Cases and Deaths Reported in FloridaCategory: Health NewsCreated: 8/26/2021 12:00:00 AMLast Editorial Review: 8/26/2021 12:00:00 AM Full Article
por Half of American Workers Support COVID Vaccination, Mask Mandates in Workplace By www.medicinenet.com Published On :: Mon, 29 Aug 2022 00:00:00 PDT Title: Half of American Workers Support COVID Vaccination, Mask Mandates in WorkplaceCategory: Health NewsCreated: 8/27/2021 12:00:00 AMLast Editorial Review: 8/27/2021 12:00:00 AM Full Article
por AHA News: New Report Details What to Know About Cardiovascular Disease Symptoms By www.medicinenet.com Published On :: Fri, 19 Aug 2022 00:00:00 PDT Title: AHA News: New Report Details What to Know About Cardiovascular Disease SymptomsCategory: Health NewsCreated: 8/18/2022 12:00:00 AMLast Editorial Review: 8/19/2022 12:00:00 AM Full Article
por New Reports on Polio: How Worried Should We Be? By www.medicinenet.com Published On :: Tue, 16 Aug 2022 00:00:00 PDT Title: New Reports on Polio: How Worried Should We Be?Category: Health NewsCreated: 8/15/2022 12:00:00 AMLast Editorial Review: 8/16/2022 12:00:00 AM Full Article
por Get Moving! Any Sports Can Lower Seniors' Odds of Early Death By www.medicinenet.com Published On :: Fri, 26 Aug 2022 00:00:00 PDT Title: Get Moving! Any Sports Can Lower Seniors' Odds of Early DeathCategory: Health NewsCreated: 8/25/2022 12:00:00 AMLast Editorial Review: 8/26/2022 12:00:00 AM Full Article
por Systematic identification of interchromosomal interaction networks supports the existence of specialized RNA factories [METHODS] By genome.cshlp.org Published On :: 2024-10-29T06:46:08-07:00 Most studies of genome organization have focused on intrachromosomal (cis) contacts because they harbor key features such as DNA loops and topologically associating domains. Interchromosomal (trans) contacts have received much less attention, and tools for interrogating potential biologically relevant trans structures are lacking. Here, we develop a computational framework that uses Hi-C data to identify sets of loci that jointly interact in trans. This method, trans-C, initiates probabilistic random walks with restarts from a set of seed loci to traverse an input Hi-C contact network, thereby identifying sets of trans-contacting loci. We validate trans-C in three increasingly complex models of established trans contacts: the Plasmodium falciparum var genes, the mouse olfactory receptor "Greek islands," and the human RBM20 cardiac splicing factory. We then apply trans-C to systematically test the hypothesis that genes coregulated by the same trans-acting element (i.e., a transcription or splicing factor) colocalize in three dimensions to form "RNA factories" that maximize the efficiency and accuracy of RNA biogenesis. We find that many loci with multiple binding sites of the same DNA-binding proteins interact with one another in trans, especially those bound by factors with intrinsically disordered domains. Similarly, clustered binding of a subset of RNA-binding proteins correlates with trans interaction of the encoding loci. We observe that these trans-interacting loci are close to nuclear speckles. These findings support the existence of trans-interacting chromatin domains (TIDs) driven by RNA biogenesis. Trans-C provides an efficient computational framework for studying these and other types of trans interactions, empowering studies of a poorly understood aspect of genome architecture. Full Article
por Clinician-Reported Barriers and Needs for Implementation of Continuous Glucose Monitoring By www.jabfm.org Published On :: 2024-10-25T09:26:14-07:00 Background: Continuous glucose monitoring (CGM) for patients with type 1 and type 2 diabetes is associated with improved clinical, behavioral, and psychosocial patient health outcomes and is part of the American Diabetes Association’s Standards of Medical Care. CGM prescription often takes place in endocrinology practices, yet 50% of adults with type 1 diabetes and 90% of all people with type 2 diabetes receive their diabetes care in primary care settings. This study examined primary care clinicians’ perceptions of barriers and resources needed to support CGM use in primary care. Methods: This qualitative study used semistructured interviews with primary care clinicians to understand barriers to CGM and resources needed to prescribe. Participants were recruited through practice-based research networks. Rapid qualitative analysis was used to summarize themes from interview findings. Results: We conducted interviews with 55 primary care clinicians across 21 states. Participants described CGM benefits for patients with varying levels of diabetes self-management and engagement. Major barriers to prescribing included lack of insurance coverage for CGM costs to patients, and time constraints. Participants identified resources needed to foster CGM prescribing, for example, clinician education, support staff, and EHR compatibility. Conclusion: Primary care clinicians face several challenges to prescribing CGM, but they are interested in learning more to help them offer it to their patients. This study reinforces the ongoing need for improved clinician education on CGM technology and continued expansion of insurance coverage for people with both type 1 and type 2 diabetes. Full Article
por Nocturnal Pressure Support Ventilation: Truth or Dare? By rc.rcjournal.com Published On :: 2024-10-25T05:44:13-07:00 Full Article
por Supporting Evidence For Pulmonary Rehabilitation in the Treatment of Long COVID By rc.rcjournal.com Published On :: 2024-10-25T05:44:13-07:00 Full Article
por Decoding biology with massively parallel reporter assays and machine learning [Reviews] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 Massively parallel reporter assays (MPRAs) are powerful tools for quantifying the impacts of sequence variation on gene expression. Reading out molecular phenotypes with sequencing enables interrogating the impact of sequence variation beyond genome scale. Machine learning models integrate and codify information learned from MPRAs and enable generalization by predicting sequences outside the training data set. Models can provide a quantitative understanding of cis-regulatory codes controlling gene expression, enable variant stratification, and guide the design of synthetic regulatory elements for applications from synthetic biology to mRNA and gene therapy. This review focuses on cis-regulatory MPRAs, particularly those that interrogate cotranscriptional and post-transcriptional processes: alternative splicing, cleavage and polyadenylation, translation, and mRNA decay. Full Article
por A circular split nanoluciferase reporter for validating and screening putative internal ribosomal entry site elements [METHOD] By rnajournal.cshlp.org Published On :: 2024-10-16T07:18:13-07:00 Internal ribosomal entry sites (IRESs) recruit the ribosome to promote translation, typically in an m7G cap-independent manner. Although IRESs are well-documented in viral genomes, they have also been reported in mammalian transcriptomes, where they have been proposed to mediate cap-independent translation of mRNAs. However, subsequent studies have challenged the idea of these "cellular" IRESs. Current methods for screening and discovering IRES activity rely on a bicistronic reporter assay, which is prone to producing false positive signals if the putative IRES sequence has a cryptic promoter or cryptic splicing sites. Here, we report an assay for screening IRES activity using a genetically encoded circular RNA comprising a split nanoluciferase (nLuc) reporter. The circular split nLuc reporter is less susceptible to the various sources of false positives that adversely affect the bicistronic IRES reporter assay and provides a streamlined method for screening IRES activity. Using the circular split nLuc reporter, we find that nine reported cellular IRESs have minimal IRES activity. Overall, the circular split nLuc reporter offers a simplified approach for identifying and validating IRESs and exhibits reduced propensity for producing the types of false positives that can occur with the bicistronic reporter assay. Full Article
por DNAJA2 and Hero11 mediate similar conformational extension and aggregation suppression of TDP-43 [REPORT] By rnajournal.cshlp.org Published On :: 2024-10-16T07:18:13-07:00 Many RNA-binding proteins (RBPs) contain low-complexity domains (LCDs) with prion-like compositions. These long intrinsically disordered regions regulate their solubility, contributing to their physiological roles in RNA processing and organization. However, this also makes these RBPs prone to pathological misfolding and aggregation that are characteristic of neurodegenerative diseases. For example, TAR DNA-binding protein 43 (TDP-43) forms pathological aggregates associated with amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). While molecular chaperones are well-known suppressors of these aberrant events, we recently reported that highly disordered, hydrophilic, and charged heat-resistant obscure (Hero) proteins may have similar effects. Specifically, Hero proteins can maintain the activity of other proteins from denaturing conditions in vitro, while their overexpression can suppress cellular aggregation and toxicity associated with aggregation-prone proteins. However, it is unclear how these protective effects are achieved. Here, we used single-molecule FRET to monitor the conformations of the aggregation-prone prion-like LCD of TDP-43. While we observed high conformational heterogeneity in wild-type LCD, the ALS-associated mutation A315T promoted collapsed conformations. In contrast, an Hsp40 chaperone, DNAJA2, and a Hero protein, Hero11, stabilized extended states of the LCD, consistent with their ability to suppress the aggregation of TDP-43. Our results link single-molecule effects on conformation to macro effects on bulk aggregation, where a Hero protein, like a chaperone, can maintain the conformational integrity of a client protein to prevent its aggregation. Full Article
por Characterization and Prediction of Organic Anion Transporting Polypeptide 1B Activity in Prostate Cancer Patients on Abiraterone Acetate Using Endogenous Biomarker Coproporphyrin I [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Organic anion transporting polypeptide (OATP) 1B1 and OATP1B3 are important hepatic transporters. We previously identified OATP1B3 being critically implicated in the disposition of abiraterone. We aimed to further investigate the effects of abiraterone on the activities of OATP1B1 and OATP1B3 utilizing a validated endogenous biomarker coproporphyrin I (CP-I). We used OATP1B-transfected cells to characterize the inhibitory potential of abiraterone against OATP1B-mediated uptake of CP-I. Inhibition constant (Ki) was incorporated into our physiologically based pharmacokinetic (PBPK) modeling to simulate the systemic exposures of CP-I among cancer populations receiving either our model-informed 500 mg or clinically approved 1000 mg abiraterone acetate (AA) dosage. Simulated data were compared with clinical CP-I concentrations determined among our nine metastatic prostate cancer patients receiving 500 mg AA treatment. Abiraterone inhibited OATP1B3-mediated, but not OATP1B1-mediated, uptake of CP-I in vitro, with an estimated Ki of 3.93 μM. Baseline CP-I concentrations were simulated to be 0.81 ± 0.26 ng/ml and determined to be 0.72 ± 0.16 ng/ml among metastatic prostate cancer patients, both of which were higher than those observed for healthy subjects. PBPK simulations revealed an absence of OATP1B3-mediated interaction between abiraterone and CP-I. Our clinical observations confirmed that CP-I concentrations remained comparable to baseline levels up to 12 weeks post 500 mg AA treatment. Using CP-I as an endogenous biomarker, we identified the inhibition of abiraterone on OATP1B3 but not OATP1B1 in vitro, which was predicted and observed to be clinically insignificant. We concluded that the interaction risk between AA and substrates of OATP1Bs is low. SIGNIFICANCE STATEMENT The authors used the endogenous biomarker coproporphyrin I (CP-I) and identified abiraterone as a moderate inhibitor of organic anion transporting polypeptide (OATP) 1B3 in vitro. Subsequent physiologically based pharmacokinetic (PBPK) simulations and clinical observations suggested an absence of OATP1B-mediated interaction between abiraterone and CP-I among prostate cancer patients. This multipronged study concluded that the interaction risk between abiraterone acetate and substrates of OATP1Bs is low, demonstrating the application of PBPK-CP-I modeling in predicting OATP1B-mediated interaction implicating abiraterone. Full Article
por Functional Characterization of Reduced Folate Carrier and Protein-Coupled Folate Transporter for Antifolates Accumulation in Non-Small Cell Lung Cancer Cells [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Antifolates are important for chemotherapy in non–small cell lung cancer (NSCLC). They mainly rely on reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) to enter cells. PCFT is supposed to be the dominant transporter of the two in tumors, as it operates optimally at acidic pH and has limited transport activity at physiological pH, whereas RFC operates optimally at neutral pH. In this study, we found RFC showed a slightly pH-dependent uptake of antifolates, with similar affinity values at pH 7.4 and 6.5. PCFT showed a highly pH-dependent uptake of antifolates, with an optimum pH of 6.0 for pemetrexed and 5.5 for methotrexate. The Michaelis-Menten constant (Km) value of PCFT for pemetrexed at pH 7.4 was more than 10 times higher than that at pH 6.5. Interestingly, we found that antifolate accumulations mediated by PCFT at acidic pH were significantly affected by the efflux transporter, breast cancer resistance protein (BCRP). The highest pemetrexed concentration was observed at pH 7.0–7.4 after a 60-minute accumulation in PCFT-expressing cells, which was further evidenced by the cytotoxicity of pemetrexed, with the IC50 value of pemetrexed at pH 7.4 being one-third of that at pH 6.5. In addition, the in vivo study indicated that increasing PCFT and RFC expression significantly enhanced the antitumor efficacy of pemetrexed despite the high expression of BCRP. These results suggest that both RFC and PCFT are important for antifolates accumulation in NSCLC, although there is an acidic microenvironment and high BCRP expression in tumors. SIGNIFICANCE STATEMENT Evaluating the role of reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) on antifolates accumulation in non–small cell lung cancer (NSCLC) is necessary for new drug designs. By using cell models, we found both RFC and PCFT were important for antifolates accumulation in NSCLC. Breast cancer resistance protein (BCRP) significantly affected PCFT-mediated antifolates accumulation at acidic pH but not RFC-mediated pemetrexed accumulation at physiological pH. High expression of PCFT or RFC enhanced the cytotoxicity and antitumor effect of pemetrexed. Full Article
por Molecular Mechanisms for the Selective Transport of Dichlorofluorescein by Human Organic Anion Transporting Polypeptide 1B1 [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Human organic anion transporting polypeptide (OATP) 1B1 and 1B3 are two highly homologous liver-specific uptake transporters. However, 2’,7’-dichlorofluorescein (DCF) is preferably transported by OATP1B1. In the present study, the molecular mechanisms for the selective transport of DCF by OATP1B1 were investigated by constructing and characterizing an array of OATP1B1/1B3 chimeras and site-directed mutagenesis. Our results show that transmembrane domain (TM) 10 is crucial for the surface expression and function of OATP1B1, in which Q541 and L545 play the most important roles in DCF transport. Replacement of TM10 in OATP1B1 with its OATP1B3 counterpart led to OATP1B1’s complete intracellular retention. Q541 and L545 may interact with DCF directly via hydrogen bonding and hydrophobic interactions. The decrease of DCF uptake by Q541A and L545S was due to their reduced binding affinity for DCF as compared with OATP1B1. In addition, Q541 and L545 are also crucial for the transport of estradiol-17β-glucuronide (E17βG) but not for the transport of estrone-3-sulfate (E3S), indicating different interaction modes between DCF/E17βG and E3S in OATP1B1. Taken together, Q541 and L545 in TM10 are critical for OATP1B1-mediated DCF uptake, but their effect is substrate-dependent. SIGNIFICANCE STATEMENT The key TMs and amino acid residues for the selective transport of DCF by OATP1B1 were identified. TM10 is crucial for the surface expression and function of OATP1B1. Within TM10, Q541 and L545 played the most significant roles and affected the function of OATP1B1 in a substrate-dependent manner. This information is crucial for a better understanding of the mechanism of the multispecificity of OATP1B1 and as a consequence the mechanism of OATP1B1-mediated drug–drug interactions. Full Article
por The Simultaneous Inhibition of Solute Carrier Family 6 Member 19 and Breast Cancer Resistance Protein Transporters Leads to an Increase of Indoxyl Sulfate (a Uremic Toxin) in Plasma and Kidney [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Solute carrier family 6 member 19 (SLC6A19) inhibitors are being studied as therapeutic agents for phenylketonuria. In this work, a potent SLC6A19 inhibitor (RA836) elevated rat kidney uremic toxin indoxyl sulfate (IDS) levels by intensity (arbitrary unit) of 13.7 ± 7.7 compared with vehicle 0.3 ± 0.1 (P = 0.01) as determined by tissue mass spectrometry imaging analysis. We hypothesized that increased plasma and kidney levels of IDS could be caused by the simultaneous inhibition of both Slc6a19 and a kidney IDS transporter responsible for excretion of IDS into urine. To test this, we first confirmed the formation of IDS through tryptophan metabolism by feeding rats a Trp-free diet. Inhibiting Slc6a19 with RA836 led to increased IDS in these rats. Next, RA836 and its key metabolites were evaluated in vitro for inhibiting kidney transporters such as organic anion transporter (OAT)1, OAT3, and breast cancer resistance protein (BCRP). RA836 inhibits BCRP with an IC50 of 0.045 μM but shows no significant inhibition of OAT1 or OAT3. Finally, RA836 analogs with either potent or no inhibition of SLC6A19 and/or BCRP were synthesized and administered to rats fed a normal diet. Plasma and kidney samples were collected to quantify IDS using liquid chromatography–mass spectrometry. Neither a SLC6A19 inactive but potent BCRP inhibitor nor a SLC6A19 active but weak BCRP inhibitor raised IDS levels, whereas compounds inhibiting both transporters caused IDS accumulation in rat plasma and kidney, supporting the hypothesis that rat Bcrp contributes to the excretion of IDS. In summary, we identified that inhibiting Slc6a19 increases IDS formation, while simultaneously inhibiting Bcrp results in IDS accumulation in the kidney and plasma. SIGNIFICANCE STATEMENT This is the first publication to decipher the mechanism for accumulation of indoxyl sulfate (IDS) (a uremic toxin) in rats via inhibition of both Slc6a19 and Bcrp. Specifically, inhibition of Slc6a19 in the gastrointestinal track increases IDS formation, and inhibition of Bcrp in the kidney blocks IDS excretion. Therefore, we should avoid inhibiting both solute carrier family 6 member 19 and breast cancer resistance protein simultaneously in humans to prevent accumulation of IDS, a known risk factor for cardiovascular disease, psychic anxiety, and mortality in chronic kidney disease patients. Full Article
por Ontogeny of Hepatic Organic Cation Transporter-1 in Rat and Human [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 The organic cation transporter (OCT)-1 mediates hepatic uptake of cationic endogenous compounds and xenobiotics. To date, limited information exists on how Oct1/OCT1 functionally develops with age in rat and human livers and how this would affect the pharmacokinetics of OCT substrates in children or juvenile animals. The functional ontogeny of rOct/hOCT was profiled in suspended rat (2–57 days old) and human hepatocytes (pediatric liver tissue donors: age 2–12 months) by determining uptake clearance of 4-[4-(dimethylamino)styryl]-N-methylpyridinium iodide (ASP+) as a known rOct/hOCT probe substrate. mRNA expression was determined in rat liver tissue corresponding to rat ages used in the functional studies, while hOCT1 mRNA expressions were determined in the same hepatocyte batches as those used for uptake studies. Maturation of rOct/hOCT activity and expression were evaluated by comparing values obtained at the various ages to the adult values. Relative to adult values (at 8 weeks), ASP+ uptake clearance in suspended rat hepatocytes aged 0, 1, 2, 3, 4, 5, and 6 weeks reached 26%, 29%, 33%, 37%, 72%, 63%, and 71%, respectively. Hepatic Oct1 mRNA expression was consistent with Oct activity (correlation coefficient of 0.92). In human hepatocytes, OCT1 activity was age dependent and also correlated with mRNA levels (correlation coefficient of 0.88). These data show that Oct1/OCT1 activities and expression mature gradually in rat/human liver, thereby mirroring the expression pattern of organic anion transporting polypeptide in rat. These high-resolution transporter ontogeny profiles will allow for more accurate prediction of the pharmacokinetics of OCT1/Oct1 substrates in pediatric populations and juvenile animals. SIGNIFICANCE STATEMENT Organic cation transporter-1 (OCT1) represents a major drug uptake transporter in human liver. This study provides high-resolution data regarding the age-dependent function of OCT1 in the liver, based on in vitro experiments with rat and human hepatocytes obtained from donors between birth and adulthood. These ontogeny profiles will inform improved age-specific physiologically based pharmacokinetic models for OCT1 drug substrates in neonates, infants, children, and adults. Full Article
por The Induction of Drug Uptake Transporter Organic Anion Transporting Polypeptide 1A2 by Radiation Is Mediated by the Nonreceptor Tyrosine Kinase v-YES-1 Yamaguchi Sarcoma Viral Oncogene Homolog 1 [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Organic anion transporting polypeptides (OATP, gene symbol SLCO) are well-recognized key determinants for the absorption, distribution, and excretion of a wide spectrum of endogenous and exogenous compounds including many antineoplastic agents. It was therefore proposed as a potential drug target for cancer therapy. In our previous study, it was found that low-dose X-ray and carbon ion irradiation both upregulated the expression of OATP family member OATP1A2 and in turn, led to a more dramatic killing effect when cancer cells were cotreated with antitumor drugs such as methotrexate. In the present study, the underlying mechanism of the phenomenon was explored in breast cancer cell line MCF-7. It was found that the nonreceptor tyrosine kinase v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1 (YES-1) was temporally coordinated with the change of OATP1A2 after irradiation. The overexpression of YES-1 significantly increased OATP1A2 both at the mRNA and protein level. The signal transducer and activator of transcription 3 (STAT3) pathway is likely the downstream target of YES-1 because phosphorylation and nuclear accumulation of STAT3 were both enhanced after overexpressing YES-1 in MCF-7 cells. Further investigation revealed that there are two possible binding sites of STAT3 localized at the upstream sequence of SLCO1A2, the encoding gene of OATP1A2. Electrophoretic mobility shift assay and chromatin immunoprecipitation analysis suggested that these two sites bound to STAT3 specifically and the overexpression of YES-1 significantly increased the association of the transcription factor with the putative binding sites. Finally, inhibition or knockdown of YES-1 attenuated the induction effect of radiation on the expression of OATP1A2. SIGNIFICANCE STATEMENT The present study found that the effect of X-rays on v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1 (YES-1) and organic anion transporting polypeptides (OATP)1A2 was temporally coordinated. YES-1 phosphorylates and increases the nuclear accumulation of signal transducer and activator of transcription 3, which in turn binds to the upstream regulatory sequences of SLCO1A2, the coding gene for OATP1A2. Hence, inhibitors of YES-1 may suppress the radiation induction effect on OATP1A2. Full Article
por Roles of the ABCG2 Transporter in Protoporphyrin IX Distribution and Toxicity [Special Section on New and Emerging Areas and Technologies in Drug Metabolism and Disposition, Part II-Minireview] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 ATP-binding cassette transporter subfamily G member 2 (ABCG2) is a membrane-bound transporter responsible for the efflux of various xenobiotics and endobiotics, including protoporphyrin IX (PPIX), an intermediate in the heme biosynthesis pathway. Certain genetic mutations and chemicals impair the conversion of PPIX to heme and/or increase PPIX production, leading to PPIX accumulation and toxicity. In mice, deficiency of ABCG2 protects against PPIX-mediated phototoxicity and hepatotoxicity by modulating PPIX distribution. In addition, in vitro studies revealed that ABCG2 inhibition increases the efficacy of PPIX-based photodynamic therapy by retaining PPIX inside target cells. In this review, we discuss the roles of ABCG2 in modulating the tissue distribution of PPIX, PPIX-mediated toxicity, and PPIX-based photodynamic therapy. SIGNIFICANCE STATEMENT This review summarized the roles of ABCG2 in modulating PPIX distribution and highlighted the therapeutic potential of ABCG2 inhibitors for the management of PPIX-mediated toxicity. Full Article
por Differential Tissue Abundance of Membrane-Bound Drug Metabolizing Enzymes and Transporter Proteins by Global Proteomics [Special Section on New and Emerging Areas and Technologies in Drug Metabolism and Disposition, Part II] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Protein abundance data of drug-metabolizing enzymes and transporters (DMETs) are useful for scaling in vitro and animal data to humans for accurate prediction and interpretation of drug clearance and toxicity. Targeted DMET proteomics that relies on synthetic stable isotope-labeled surrogate peptides as calibrators is routinely used for the quantification of selected proteins; however, the technique is limited to the quantification of a small number of proteins. Although the global proteomics-based total protein approach (TPA) is emerging as a better alternative for large-scale protein quantification, the conventional TPA does not consider differential sequence coverage by identifying unique peptides across proteins. Here, we optimized the TPA approach by correcting protein abundance data by the sequence coverage, which was applied to quantify 54 DMETs for characterization of 1) differential tissue DMET abundance in the human liver, kidney, and intestine, and 2) interindividual variability of DMET proteins in individual intestinal samples (n = 13). Uridine diphosphate-glucuronosyltransferase 2B7 (UGT2B7), microsomal glutathione S-transferases (MGST1, MGST2, and MGST3) carboxylesterase 2 (CES2), and multidrug resistance-associated protein 2 (MRP2) were expressed in all three tissues, whereas, as expected, four cytochrome P450s (CYP3A4, CYP3A5, CYP2C9, and CYP4F2), UGT1A1, UGT2B17, CES1, flavin-containing monooxygenase 5, MRP3, and P-glycoprotein were present in the liver and intestine. The top three DMET proteins in individual tissues were: CES1>CYP2E1>UGT2B7 (liver), CES2>UGT2B17>CYP3A4 (intestine), and MGST1>UGT1A6>MGST2 (kidney). CYP3A4, CYP3A5, UGT2B17, CES2, and MGST2 showed high interindividual variability in the intestine. These data are relevant for enhancing in vitro to in vivo extrapolation of drug absorption and disposition and can be used to enhance the accuracy of physiologically based pharmacokinetic prediction of systemic and tissue concentration of drugs. SIGNIFICANCE STATEMENT This study quantified the abundance and compositions of drug-metabolizing enzymes and transporters in pooled human liver, intestine, and kidney microsomes as well as individual intestinal microsomes using an optimized global proteomics approach. The data revealed large intertissue differences in the abundance of these proteins and high intestinal interindividual variability in the levels of cytochrome P450s (e.g., CYP3A4 and CYP3A5), uridine diphosphate-glucuronosyltransferase 2B17, carboxylesterase 2, and microsomal glutathione S-transferase 2. These data are applicable for the prediction of first-pass metabolism and tissue-specific drug clearance. Full Article
por Improving Maternity Care Where Home Births Are Still the Norm: Establishing Local Birthing Centers in Guatemala That Incorporate Traditional Midwives By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 ABSTRACTMore than half of births among Indigenous women in Guatemala are still being attended at home by providers with no formal training. We describe the incorporation of comadronas (traditional midwives) into casas maternas (birthing centers) in the rural highlands of western Guatemala. Although there was initial resistance to the casa, comadronas and clients have become increasingly enthusiastic about them. The casas provide the opportunity for comadronas to continue the cultural traditions of prayers, massages, and other practices that honor the vital spiritual dimension of childbirth close to home in a home-like environment with extended family support while at the same time providing a safer childbirth experience in which complications can be detected by trained personnel at the casa, managed locally, or promptly referred to a higher-level facility. Given the growing acceptance of this innovation in an environment in which geographical, financial, and cultural barriers to deliveries at higher-level facilities lead most women to deliver at home, casas maternas represent a feasible option for reducing the high level of maternal mortality in Guatemala.This article provides an update on the growing utilization of casas and provides new insights into the role of comadronas as birthing team members and enthusiastic promotors of casas maternas as a preferable alternative to home births. Through the end of 2023, these casas maternas had cared for 4,322 women giving birth. No maternal deaths occurred at a casa, but 4 died after referral.The Ministry of Health of Guatemala has recently adopted this approach and has begun to implement it in other rural areas where home births still predominate. This approach deserves consideration as a viable and feasible option for reducing maternal mortality throughout the world where home births are still common, while at the same time providing women with respectful and culturally appropriate care. Full Article
por A Cosmopolitan Argument for Temporary “Diagonal” Short-Term Surgical Missions as a Component of Surgical Systems Strengthening By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 Full Article
por Development and Piloting of Implementation Strategies to Support Delivery of a Clinical Intervention for Postpartum Hemorrhage in Four sub-Saharan Africa Countries By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 ABSTRACTIntroduction:Postpartum hemorrhage (PPH) remains the leading cause of maternal mortality. A new clinical intervention (E-MOTIVE) holds the potential to improve early PPH detection and management. We aimed to develop and pilot implementation strategies to support uptake of this intervention in Kenya, Nigeria, South Africa, and Tanzania.Methods:Implementation strategy development: We triangulated findings from qualitative interviews, surveys and a qualitative evidence synthesis to identify current PPH care practices and influences on future intervention implementation. We mapped influences using implementation science frameworks to identify candidate implementation strategies before presenting these at stakeholder consultation and design workshops to discuss feasibility, acceptability, and local adaptations. Piloting: The intervention and implementation strategies were piloted in 12 health facilities (3 per country) over 3 months. Interviews (n=58), case report forms (n=1,269), and direct observations (18 vaginal births, 7 PPHs) were used to assess feasibility, acceptability, and fidelity.Results:Implementation strategy development: Key influences included shortages of drugs, supplies, and staff, limited in-service training, and perceived benefits of the intervention (e.g., more accurate PPH detection and reduced PPH mortality). Proposed implementation strategies included a PPH trolley, on-site simulation-based training, champions, and audit and feedback. Country-specific adaptations included merging the E-MOTIVE intervention with national maternal health trainings, adapting local PPH protocols, and PPH trollies depending on staff needs. Piloting: Intervention and implementation strategy fidelity differed within and across countries. Calibrated drapes resulted in earlier and more accurate PPH detection but were not consistently used at the start. Implementation strategies were feasible to deliver; however, some instances of limited use were observed (e.g., PPH trolley and skills practice after training).Conclusion:Systematic intervention development, piloting, and process evaluation helped identify initial challenges related to intervention fidelity, which were addressed ahead of a larger-scale effectiveness evaluation. This has helped maximize the internal validity of the trial. Full Article
por Factors Influencing the Central Nervous System (CNS) Distribution of the Ataxia Telangiectasia Mutated and Rad3-Related Inhibitor Elimusertib (BAY1895344): Implications for the Treatment of CNS Tumors [Metabolism, Transport, and Pharmacogenetics] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Glioblastoma (GBM) is a disease of the whole brain, with infiltrative tumor cells protected by an intact blood-brain barrier (BBB). GBM has a poor prognosis despite aggressive treatment, in part due to the lack of adequate drug permeability at the BBB. Standard of care GBM therapies include radiation and cytotoxic chemotherapy that lead to DNA damage. Subsequent activation of DNA damage response (DDR) pathways can induce resistance. Various DDR inhibitors, targeting the key regulators of these pathways such as ataxia telangiectasia mutated and Rad3-related (ATR), are being explored as radio- and chemosensitizers. Elimusertib, a novel ATR kinase inhibitor, can prevent repair of damaged DNA, increasing efficacy of DNA-damaging cytotoxic therapies. Robust synergy was observed in vitro when elimusertib was combined with the DNA-damaging agent temozolomide; however, we did not observe improvement with this combination in in vivo efficacy studies in GBM orthotopic tumor-bearing mice. This in vitro–in vivo disconnect was explored to understand factors influencing central nervous system (CNS) distribution of elimusertib and reasons for lack of efficacy. We observed that elimusertib is rapidly cleared from systemic circulation in mice and would not maintain adequate exposure in the CNS for efficacious combination therapy with temozolomide. CNS distribution of elimusertib is partially limited by P-glycoprotein efflux at the BBB, and high binding to CNS tissues leads to low levels of pharmacologically active (unbound) drug in the brain. Acknowledging the potential for interspecies differences in pharmacokinetics, these data suggest that clinical translation of elimusertib in combination with temozolomide for treatment of GBM may be limited. SIGNIFICANCE STATEMENT This study examined the disconnect between the in vitro synergy and in vivo efficacy of elimusertib/temozolomide combination therapy by exploring systemic and central nervous system (CNS) distributional pharmacokinetics. Results indicate that the lack of improvement in in vivo efficacy in glioblastoma (GBM) patient-derived xenograft (PDX) models could be attributed to inadequate exposure of pharmacologically active drug concentrations in the CNS. These observations can guide further exploration of elimusertib for the treatment of GBM or other CNS tumors. Full Article
por Nonclinical Profile of PF-06952229 (MDV6058), a Novel TGF{beta}RI/Activin Like Kinase 5 Inhibitor Supports Clinical Evaluation in Cancer [Drug Discovery and Translational Medicine] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 The development of transforming growth factor βreceptor inhibitors (TGFβRi) as new medicines has been affected by cardiac valvulopathy and arteriopathy toxicity findings in nonclinical toxicology studies. PF-06952229 (MDV6058) selected using rational drug design is a potent and selective TGFβRI inhibitor with a relatively clean off-target selectivity profile and good pharmacokinetic properties across species. PF-06952229 inhibited clinically translatable phospho-SMAD2 biomarker (≥60%) in human and cynomolgus monkey peripheral blood mononuclear cells, as well as in mouse and rat splenocytes. Using an optimized, intermittent dosing schedule (7-day on/7-day off/cycle; 5 cycles), PF-06952229 demonstrated efficacy in a 63-day syngeneic MC38 colon carcinoma mouse model. In the pivotal repeat-dose toxicity studies (rat and cynomolgus monkey), PF-06952229 on an intermittent dosing schedule (5-day on/5-day off cycle; 5 cycles, 28 doses) showed no cardiac-related adverse findings. However, new toxicity findings related to PF-06952229 included reversible hepatocellular (hepatocyte necrosis with corresponding clinically monitorable transaminase increases) and lung (hemorrhage with mixed cell inflammation) findings at ≥ targeted projected clinical efficacious exposures. Furthermore, partially reversible cartilage hypertrophy (trachea and femur in rat; femur in monkey) and partially to fully reversible, clinically monitorable decreases in serum phosphorus and urinary phosphate at ≥ projected clinically efficacious exposures were observed. Given the integral role of TGFβ in endochondral bone formation, cartilage findings in toxicity studies have been observed with other TGFβRi classes of compounds. The favorable cumulative profile of PF-06952229 in biochemical, pharmacodynamic, pharmacokinetic, and nonclinical studies allowed for its evaluation in cancer patients using the intermittent dosing schedule (7-day on/7-day off) and careful protocol-defined monitoring. SIGNIFICANCE STATEMENT Only a few TGFβRi have progressed for clinical evaluation due to adverse cardiac findings in pivotal nonclinical toxicity studies. The potential translations of such findings in patients are of major concern. Using a carefully optimized intermittent dosing schedule, PF-06952229 has demonstrated impressive pharmacological efficacy in the syngeneic MC38 colon carcinoma mouse model. Additionally, a nonclinical toxicology package without cardiovascular liabilities and generally monitorable toxicity profile has been completed. The compound presents an acceptable International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use S9-compliant profile for the intended-to-treat cancer patients. Full Article
por Effects of Dual Inhibition at Dopamine Transporter and {sigma} Receptors in the Discriminative-Stimulus Effects of Cocaine in Male Rats [Behavioral Pharmacology] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Previous studies demonstrated that sigma receptor (R) antagonists alone fail to alter cocaine self-administration despite blocking various other effects of cocaine. However, R antagonists when combined with dopamine transporter (DAT) inhibitors substantially decrease cocaine self-administration. To better understand the effects of this combination, the present study examined the effects of R antagonist and DAT inhibitor combinations in male rats discriminating cocaine (10 mg/kg, i.p.) from saline injections. The DAT inhibitors alone [(–)-2-β-carbomethoxy-3-β-(4-fluorophenyl)tropane 1,5-naphthalenedisulfonate monohydrate (WIN 35,428) and methylphenidate] at low (0.1-mg/kg) doses that were minimally active failed to shift the dose-effect function for discriminative-stimulus effects of cocaine to the left more than 2-fold. At 0.32 mg/kg the DAT inhibitors alone shifted the cocaine dose-effect function leftward 24- or 6.6-fold, respectively. The R antagonists (BD1008, BD1047, and BD1063) failed to fully substitute for cocaine, although BD1008 and BD1047 substituted partially. At 10 mg/kg, BD1008, BD1047, or BD1063 alone shifted the cocaine dose-effect function leftward less than 6.0-fold. In combination with 0.1 mg/kg WIN 35,428, the 10 mg/kg doses of R antagonists shifted the cocaine dose-effect function from 12.3- to 36.7-fold leftward, and with 0.32 mg/kg WIN 35,428 from 14.3- to 440-fold leftward. In combination with 0.1 mg/kg methylphenidate, those R antagonist doses shifted the cocaine dose-effect function from 5.5- to 55.0-fold leftward, and with 0.32 mg/kg methylphenidate from 10.5- to 48.1-fold leftward. The present results suggest that dual DAT/R inhibition produces agonist-like subjective effects that may promote decreases in self-administration obtained in previous studies. SIGNIFICANCE STATEMENT There is currently no approved medication for treating stimulant abuse, although dopamine uptake inhibitors in combination with sigma receptor (R) antagonists decrease cocaine self-administration in laboratory animals. The present study assessed how this combination alters the discriminative-stimulus effects of cocaine in male rats. Results suggest that concurrent dopamine uptake inhibition and R antagonism together may promote decreases in self-administration, possibly by mimicking the subjective effects extant when subjects cease continued cocaine self-administration. Full Article
por Cannabis and Cannabinoid Signaling: Research Gaps and Opportunities [Special Section: Cannabinoid Signaling in Human Health and Disease-Commentary] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Cannabis and its products have been used for centuries for both medicinal and recreational purposes. The recent widespread legalization of cannabis has vastly expanded its use in the United States across all demographics except for adolescents. Meanwhile, decades of research have advanced our knowledge of cannabis pharmacology and particularly of the endocannabinoid system with which the components of cannabis interact. This research has revealed multiple targets and approaches for manipulating the system for therapeutic use and to ameliorate cannabis toxicity or cannabis use disorder. Research has also led to new questions that underscore the potential risks of its widespread use, particularly the enduring consequences of exposure during critical windows of brain development or for consumption of large daily doses of cannabis with high content 9-tetrahydrocannabinol. This article highlights current neuroscience research on cannabis that has shed light on therapeutic opportunities and potential adverse consequences of misuse and points to gaps in knowledge that can guide future research. SIGNIFICANCE STATEMENT Cannabis use has escalated with its increased availability. Here, the authors highlight the challenges of cannabis research and the gaps in our knowledge of cannabis pharmacology and of the endocannabinoid system that it targets. Future research that addresses these gaps is needed so that the endocannabinoid system can be leveraged for safe and effective use. Full Article
por Neuroactive Kynurenines as Pharmacological Targets: New Experimental Tools and Exciting Therapeutic Opportunities [75th Anniversary Celebration Collection Special Section] By pharmrev.aspetjournals.org Published On :: 2024-10-16T07:40:25-07:00 Both preclinical and clinical studies implicate functional impairments of several neuroactive metabolites of the kynurenine pathway (KP), the major degradative cascade of the essential amino acid tryptophan in mammals, in the pathophysiology of neurologic and psychiatric diseases. A number of KP enzymes, such as tryptophan 2,3-dioxygenase (TDO2), indoleamine 2,3-dioxygenases (IDO1 and IDO2), kynurenine aminotransferases (KATs), kynurenine 3-monooxygenase (KMO), 3-hydroxyanthranilic acid oxygenase (3-HAO), and quinolinic acid phosphoribosyltransferase (QPRT), control brain KP metabolism in health and disease and are therefore increasingly considered to be promising targets for the treatment of disorders of the nervous system. Understanding the distribution, cellular expression, and regulation of KP enzymes and KP metabolites in the brain is therefore critical for the conceptualization and implementation of successful therapeutic strategies. Significance Statement Studies have implicated the kynurenine pathway of tryptophan in the pathophysiology of neurologic and psychiatric diseases. Key enzymes of the kynurenine pathway regulate brain metabolism in both health and disease, making them promising targets for treating these disorders. Therefore, understanding the distribution, cellular expression, and regulation of these enzymes and metabolites in the brain is critical for developing effective therapeutic strategies. This review endeavors to describe these processes in detail.: Full Article
por Low-Field (64 mT) Portable MRI for Rapid Point-of-Care Diagnosis of Dissemination in Space in Patients Presenting with Optic Neuritis [CLINICAL PRACTICE] By www.ajnr.org Published On :: 2024-11-07T15:14:12-08:00 BACKGROUND AND PURPOSE: Low-field 64 mT portable brain MRI has recently shown diagnostic promise for MS. This study aimed to evaluate the utility of portable MRI (pMRI) in assessing dissemination in space (DIS) in patients presenting with optic neuritis and determine whether deploying pMRI in the MS clinic can shorten the time from symptom onset to MRI. MATERIALS AND METHODS: Newly diagnosed patients with optic neuritis referred to a tertiary academic MS center from July 2022 to January 2024 underwent both point-of-care pMRI and subsequent 3T conventional MRI (cMRI). Images were evaluated for periventricular (PV), juxtacortical (JC), and infratentorial (IT) lesions. DIS was determined on brain MRI per 2017 McDonald criteria. Test characteristics were computed by using cMRI as the reference. Interrater and intermodality agreement between pMRI and cMRI were evaluated by using the Cohen . Time from symptom onset to pMRI and cMRI during the study period was compared with the preceding 1.5 years before pMRI implementation by using Kruskal-Wallis with post hoc Dunn tests. RESULTS: Twenty patients (median age: 32.5 years [interquartile range {IQR}, 28–40]; 80% women) were included, of whom 9 (45%) and 5 (25%) had DIS on cMRI and pMRI, respectively. Median time interval between pMRI and cMRI was 7 days (IQR, 3.5–12.5). Interrater agreement was very good for PV (95%, = 0.89), and good for JC and IT lesions (90%, = 0.69 for both). Intermodality agreement was good for PV (90%, = 0.80) and JC (85%, = 0.63), and moderate for IT lesions (75%, = 0.42) and DIS (80%, = 0.58). pMRI had a sensitivity of 56% and specificity of 100% for DIS. The median time from symptom onset to pMRI was significantly shorter (8.5 days [IQR 7–12]) compared with the interval to cMRI before pMRI deployment (21 days [IQR 8–49], n = 50) and after pMRI deployment (15 days [IQR 12–29], n = 30) (both P < .01). Time from symptom onset to cMRI in those periods was not significantly different (P = .29). CONCLUSIONS: In patients with optic neuritis, pMRI exhibited moderate concordance, moderate sensitivity, and high specificity for DIS compared with cMRI. Its integration into the MS clinic reduced the time from symptom onset to MRI. Further studies are warranted to evaluate the role of pMRI in expediting early MS diagnosis and as an imaging tool in resource-limited settings. Full Article
por Diffusion Analysis of Intracranial Epidermoid, Head and Neck Epidermal Inclusion Cyst, and Temporal Bone Cholesteatoma [CLINICAL PRACTICE] By www.ajnr.org Published On :: 2024-11-07T15:14:12-08:00 BACKGROUND AND PURPOSE: Intracranial epidermoids temporal bone cholesteatomas, and head and neck epidermal inclusion cysts are typically slow-growing, benign conditions arising from ectodermal tissue. They exhibit increased signal on DWI. While much of the imaging literature describes these lesions as showing diffusion restriction, we investigated these qualitative signal intensities and interpretations of restricted diffusion with respect to normal brain structures. This study aimed to quantitatively evaluate the ADC values and histogram features of these lesions. MATERIALS AND METHODS: This retrospective study included children with histologically confirmed diagnoses of intracranial epidermoids, temporal bone cholesteatomas, or head and neck epidermal inclusion cysts. Lesions were segmented, and voxelwise calculation of ADC values was performed along with histogram analysis. ADC calculations were validated with a second analysis software to ensure accuracy. Normal brain ROIs—including the cerebellum, white matter, and thalamus—served as normal comparators. Correlational analysis and Bland-Altman plots assessed agreement among software tools for ADC calculations. Differences in the distribution of values between the lesions and normal brain tissues were assessed using the Wilcoxon rank sum and Kruskal-Wallis tests. RESULTS: Forty-eight pathology-proved cases were included in this study. Among them, 13 (27.1%) patients had intracranial epidermoids 14 (29.2%) had head and neck epidermal inclusion cysts, and 21 (43.7%) had temporal bone cholesteatomas. The mean age was 8.67 (SD, 5.30) years, and 27 (56.3%) were female. The intraclass correlation for absolute agreement for lesional ADC between the 2 software tools was 0.997 (95% CI, 0.995–0.998). The intracranial epidermoid head and neck epidermal inclusion cyst, and temporal bone cholesteatoma median ADC values were not significantly different (973.7 versus 875.7 versus 933.2 x 10–6 mm2/s, P = .265). However, the ADCs of the 3 types of lesions were higher than those of 3 normal brain tissue types (933 versus 766, x 10–6 mm2/s, P < .001). CONCLUSIONS: The ADC values of intracranial epidermoids, temporal bone cholesteatomas, and head and neck epidermal inclusion cysts are higher than those of normal brain regions. It is not accurate to simply classify these lesions as exhibiting restricted diffusion or reduced diffusivity without considering the tissue used for comparison. The observed hyperintensity on DWI compared with the brain is likely attributable to a relatively higher contribution of the T2 shinethrough effect. Full Article
por The diagnostic odyssey of a patient with dihydropyrimidinase deficiency: a case report and review of the literature [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Dihydropyrimidinase (DHP) deficiency is an autosomal recessive metabolic disorder caused by biallelic pathogenic variants of DPYS. Patients with DHP deficiency exhibit a broad spectrum of phenotypes, ranging from severe neurological and gastrointestinal involvement to cases with no apparent symptoms. The biochemical diagnosis of DHP deficiency is based on the detection of a significant amount of dihydropyrimidines in urine, plasma, and cerebrospinal fluid samples. Molecular genetic testing, specifically the identification of biallelic pathogenic variants in DPYS, has proven instrumental in confirming the diagnosis and facilitating family studies. This case study documents the diagnostic journey of an 18-yr-old patient with DHP deficiency, highlighting features at the severe end of the clinical spectrum. Notably, our patient exhibited previously unreported skeletal features that positively responded to bisphosphonate treatment, contributing valuable insights to the clinical characterization of DHP deficiency. Additionally, a novel DPYS variant was identified and confirmed pathogenicity through metabolic testing, further expanding the variant spectrum of the gene. Our case emphasizes the importance of a comprehensive diagnostic approach using genetic sequencing and metabolic testing for accurate diagnosis. Full Article
por PD-L1+ diffuse large B-cell lymphoma with extremely high mutational burden and microsatellite instability due to acquired PMS2 mutation [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 We present a unique case of a single patient presenting with two mutationally distinct, PD-L1+ diffuse large B-cell lymphomas (DLBCLs). One of these DLBCLs demonstrated exceptionally high mutational burden (eight disease-associated variants and 41 variants of undetermined significance) with microsatellite instability (MSI) and an acquired PMS2 mutation with loss of PMS2 protein expression, detected postchemotherapy. This report, while highlighting the extent of possible tumor heterogeneity across separate clonal expansions as well as possible syndromic B-cell neoplasia, supports the notion that, although rare, PD-L1 expression and associated states permissive of high mutational burden (such as mismatch repair gene loss of function/MSI) should be more routinely considered in DLBCLs. Appropriate testing may be predictive of outcome and inform the utility of targeted therapy in these genetically diverse and historically treatment-refractory malignancies. Full Article
por Deep molecular tracking over the 12-yr development of endometrial cancer from hyperplasia in a single patient [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Although the progressive histologic steps leading to endometrial cancer (EndoCA), the most common female reproductive tract malignancy, from endometrial hyperplasia are well-established, the molecular changes accompanying this malignant transformation in a single patient have never been described. We had the unique opportunity to investigate the paired histologic and molecular features associated with the 12-yr development of EndoCA in a postmenopausal female who could not undergo hysterectomy and instead underwent progesterone treatment. Using a specially designed 58-gene next-generation sequencing panel, we analyzed a total of 10 sequential biopsy samples collected over this time frame. A total of eight pathogenic/likely pathogenic mutations in seven genes, APC, ARID1A, CTNNB1, CDKN2A, KRAS, PTEN, and TP53, were identified. A PTEN nonsense mutation p.W111* was present in all samples analyzed except histologically normal endometrium. Apart from this PTEN mutation, the only other recurrent mutation was KRAS G12D, which was present in six biopsy samplings, including histologically normal tissue obtained at the patient's first visit but not detectable in the cancer. The PTEN p.W111* mutant allele fractions were lowest in benign, inactive endometrial glands (0.7%), highest in adenocarcinoma (36.9%), and, notably, were always markedly reduced following progesterone treatment. To our knowledge, this report provides the first molecular characterization of EndoCA development in a single patient. A single PTEN mutation was present throughout the 12 years of cancer development. Importantly, and with potential significance toward medical and nonsurgical management of EndoCA, progesterone treatments were consistently noted to markedly decrease PTEN mutant allele fractions to precancerous levels. Full Article
por Pazopanib elicits remarkable response in metastatic porocarcinoma: a functional precision medicine approach [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Metastatic porocarcinomas (PCs) are vanishingly rare, highly aggressive skin adnexal tumors with mortality rates exceeding 70%. Their rarity has precluded the understanding of their disease pathogenesis, let alone the conduct of clinical trials to evaluate treatment strategies. There are no effective agents for unresectable PCs. Here, we successfully demonstrate how functional precision medicine was implemented in the clinic for a metastatic PC with no known systemic treatment options. Comprehensive genomic profiling of the tumor specimen did not yield any actionable genomic aberrations. However, ex vivo drug testing predicted pazopanib efficacy, and indeed, administration of pazopanib elicited remarkable clinicoradiological response. Pazopanib and its class of drugs should be evaluated for efficacy in other cases of PC, and the rationale for efficacy should be determined when PC tumor models become available. A functional precision medicine approach could be useful to derive effective treatment options for rare cancers. Full Article
por Prostate cancer patient stratification by molecular signatures in the Veterans Precision Oncology Data Commons [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Veterans are at an increased risk for prostate cancer, a disease with extraordinary clinical and molecular heterogeneity, compared with the general population. However, little is known about the underlying molecular heterogeneity within the veteran population and its impact on patient management and treatment. Using clinical and targeted tumor sequencing data from the National Veterans Affairs health system, we conducted a retrospective cohort study on 45 patients with advanced prostate cancer in the Veterans Precision Oncology Data Commons (VPODC), most of whom were metastatic castration-resistant. We characterized the mutational burden in this cohort and conducted unsupervised clustering analysis to stratify patients by molecular alterations. Veterans with prostate cancer exhibited a mutational landscape broadly similar to prior studies, including KMT2A and NOTCH1 mutations associated with neuroendocrine prostate cancer phenotype, previously reported to be enriched in veterans. We also identified several potential novel mutations in PTEN, MSH6, VHL, SMO, and ABL1. Hierarchical clustering analysis revealed two subgroups containing therapeutically targetable molecular features with novel mutational signatures distinct from those reported in the Catalogue of Somatic Mutations in Cancer database. The clustering approach presented in this study can potentially be used to clinically stratify patients based on their distinct mutational profiles and identify actionable somatic mutations for precision oncology. Full Article
por Novel pathogenic UQCRC2 variants in a female with normal neurodevelopment [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Electron transport chain (ETC) disorders are a group of rare, multisystem diseases caused by impaired oxidative phosphorylation and energy production. Deficiencies in complex III (CIII), also known as ubiquinol–cytochrome c reductase, are particularly rare in humans. Ubiquinol–cytochrome c reductase core protein 2 (UQCRC2) encodes a subunit of CIII that plays a crucial role in dimerization. Several pathogenic UQCRC2 variants have been identified in patients presenting with metabolic abnormalities that include lactic acidosis, hyperammonemia, hypoglycemia, and organic aciduria. Almost all previously reported UQCRC2-deficient patients exhibited neurodevelopmental involvement, including developmental delays and structural brain anomalies. Here, we describe a girl who presented at 3 yr of age with lactic acidosis, hyperammonemia, and hypoglycemia but has not shown any evidence of neurodevelopmental dysfunction by age 15. Whole-exome sequencing revealed compound heterozygosity for two novel variants in UQCRC2: c.1189G>A; p.Gly397Arg and c.437T>C; p.Phe146Ser. Here, we discuss the patient's clinical presentation and the likely pathogenicity of these two missense variants. Full Article
por Rapid genome diagnosis of alveolar capillary dysplasia leading to treatment in a child with respiratory and cardiac failure [RESEARCH REPORT] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Alveolar capillary dysplasia (ACD) is a fatal disorder that typically presents in the neonatal period with refractory hypoxemia and pulmonary hypertension. Lung biopsy is traditionally required to establish the diagnosis. We report a 22-mo-old male who presented with anemia, severe pulmonary hypertension, and right heart failure. He had a complicated hospital course resulting in cardiac arrest and requirement for extracorporeal membrane oxygenation. Computed tomography of the chest showed a heterogenous pattern of interlobular septal thickening and pulmonary edema. The etiology of his condition was unknown, lung biopsy was contraindicated because of his medical fragility, and discussions were held to move to palliative care. Rapid whole-genome sequencing (rWGS) was performed. In 2 d it resulted, revealing a novel FOXF1 gene pathogenic variant that led to the presumptive diagnosis of atypical ACD. Cases of atypical ACD have been reported with survival in patients using medical therapy or lung transplantation. Based on the rWGS diagnosis and more favorable potential of atypical ACD, aggressive medical treatment was pursued. The patient was discharged home after 67 d in the hospital; he is currently doing well more than 30 mo after his initial presentation with only one subsequent hospitalization and no requirement for lung transplantation. Our case reveals the potential for use of rWGS in a critically ill child in which the diagnosis is unknown. rWGS and other advanced genetic tests can guide clinical management and expand our understanding of atypical ACD and other conditions. Full Article
por The importance of escalating molecular diagnostics in patients with low-grade pediatric brain cancer [PRECISION MEDICINE IN PRACTICE] By molecularcasestudies.cshlp.org Published On :: 2024-01-10T08:13:38-08:00 Pilocytic astrocytomas are the most common pediatric brain tumors, typically presenting as low-grade neoplasms. We report two cases of pilocytic astrocytoma with atypical tumor progression. Case 1 involves a 12-yr-old boy with an unresectable suprasellar tumor, negative for BRAF rearrangement but harboring a BRAF p.V600E mutation. He experienced tumor size reduction and stable disease following dabrafenib treatment. Case 2 describes a 6-yr-old boy with a thalamic tumor that underwent multiple resections, with no actionable driver detected using targeted next-generation sequencing. Whole-genome and RNA-seq analysis identified an internal tandem duplication in FGFR1 and RAS pathway activation. Future management options include FGFR1 inhibitors. These cases demonstrate the importance of escalating molecular diagnostics for pediatric brain cancer, advocating for early reflexing to integrative whole-genome sequencing and transcriptomic profiling when targeted panels are uninformative. Identifying molecular drivers can significantly impact treatment decisions and improve patient outcomes. Full Article
por Support for primary care prescribing for adult ADHD in England: national survey By bjgp.org Published On :: 2024-10-31T16:05:26-07:00 BackgroundAttention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, for which there are effective pharmacological treatments that improve symptoms and reduce complications. Guidelines published by the National Institute for Health and Care Excellence recommend that primary care practitioners prescribe medication for adult ADHD under shared-care agreements with Adult Mental Health Services (AMHS). However, provision remains uneven, with some practitioners reporting a lack of support.AimThis study aimed to describe elements of support, and their availability/use, in primary care prescribing for adult ADHD medication in England to improve access for this underserved population and inform service improvement.Design and settingCross-sectional surveys were used to elicit data from commissioners, health professionals (HPs), and people with lived experience of ADHD (LE) across England about elements supporting pharmacological treatment of ADHD in primary care.MethodThree interlinked cross-sectional surveys were used to ask every integrated care board in England (commissioners), along with convenience samples of HPs and LEs, about prescribing rates, AMHS availability, wait times, and shared-care agreement protocols/policies for the pharmacological treatment of ADHD in primary care. Descriptive analyses, percentages, and confidence intervals were used to summarise responses by stakeholder group. Variations in reported provision and practice were explored and displayed visually using mapping software.ResultsData from 782 responders (42 commissioners, 331 HPs, 409 LEs) revealed differences in reported provision by stakeholder group, including for prescribing (95% of HPs versus 64% of LEs). In all, >40% of responders reported extended AMHS wait times of ≥2 years. There was some variability by NHS region – for example, London had the lowest reported extended wait time (25%), while East of England had the highest (55%).ConclusionElements supporting appropriate shared-care prescribing of ADHD medication via primary care are not universally available in England. Coordinated approaches are needed to address these gaps. Full Article
por PBRNs: Past, Present, and Future: A NAPCRG Report on the Practice-Based Research Network Conference. [Family Medicine Updates] By www.annfammed.org Published On :: 2024-09-23T14:00:14-07:00 Full Article
por The Odyssey of HOMER: Comparative Effectiveness Research on Medication for Opioid Use Disorder During the COVID-19 Pandemic [Special Report] By www.annfammed.org Published On :: 2024-09-23T14:00:14-07:00 The usual challenges of conducting primary care research, including randomized trials, have been exacerbated, and new ones identified, during the COVID-19 pandemic. HOMER (Home versus Office for Medication Enhanced Recovery; subsequently, Comparing Home, Office, and Telehealth Induction for Medication Enhanced Recovery) is a pragmatic, comparative-effectiveness research trial that aims to answer a key question from patients and clinicians: What is the best setting in which to start treatment with buprenorphine for opioid use disorder for this patient at this time? In this article, we describe the difficult journey to find the answer. The HOMER study began as a randomized trial comparing treatment outcomes in patients starting treatment with buprenorphine via induction at home (unobserved) vs in the office (observed, synchronous). The study aimed to enroll 1,000 participants from 100 diverse primary care practices associated with the State Networks of Colorado Ambulatory Practices and Partners and the American Academy of Family Physicians National Research Network. The research team faced unexpected challenges related to the COVID-19 pandemic and dramatic changes in the opioid epidemic. These challenges required changes to the study design, protocol, recruitment intensity, and funding conversations, as well as patience. As this is a participatory research study, we sought, documented, and responded to practice and patient requests for adaptations. Changes included adding a third study arm using telehealth induction (observed via telephone or video, synchronous) and switching to a comprehensive cohort design to answer meaningful patient-centered research questions. Using a narrative approach based on the Greek myth of Homer, we describe here the challenges and adaptations that have provided the opportunity for HOMER to thrive and find the way home. These clinical trial strategies may apply to other studies faced with similar cultural and extreme circumstances. Full Article