Title: Polio
Category: Diseases and Conditions
Created: 9/18/2009 12:00:00 AM
Last Editorial Review: 8/17/2022 12:00:00 AM

Title: Monkeypox Cases May Finally Be Ebbing, With Declines Seen in Europe, WHO Says
Category: Health News
Created: 8/25/2022 12:00:00 AM
Last Editorial Review: 8/25/2022 12:00:00 AM

Title: Fecal Transplant Treatments Could Transmit Monkeypox, FDA Warns
Category: Health News
Created: 8/24/2022 12:00:00 AM
Last Editorial Review: 8/25/2022 12:00:00 AM

Title: Want That Pill to Work Fast? Your Body Position Matters
Category: Health News
Created: 8/17/2022 12:00:00 AM
Last Editorial Review: 8/17/2022 12:00:00 AM

Title: Major Gene Study Spots DNA Tied to Autism, Other Disorders
Category: Health News
Created: 8/19/2022 12:00:00 AM
Last Editorial Review: 8/19/2022 12:00:00 AM

Title: Erectile Dysfunction (ED, Impotence)
Category: Diseases and Conditions
Created: 12/31/1997 12:00:00 AM
Last Editorial Review: 7/25/2022 12:00:00 AM

Title: Being Social May Be Key to 'Sense of Purpose' as You Age
Category: Health News
Created: 7/12/2022 12:00:00 AM
Last Editorial Review: 7/12/2022 12:00:00 AM

Title: Get Moving! Any Sports Can Lower Seniors' Odds of Early Death
Category: Health News
Created: 8/25/2022 12:00:00 AM
Last Editorial Review: 8/26/2022 12:00:00 AM

Title: CDC Panel Urges Seniors to Get New, More Potent Flu Shot This Fall
Category: Health News
Created: 6/23/2022 12:00:00 AM
Last Editorial Review: 6/23/2022 12:00:00 AM

Title: Pot Users Are Less Prone to Sinus Problems
Category: Health News
Created: 8/1/2022 12:00:00 AM
Last Editorial Review: 8/2/2022 12:00:00 AM

Title: Postpartum Depression Can Hit Both Mom & Dad, Sometimes at Same Time
Category: Health News
Created: 6/27/2022 12:00:00 AM
Last Editorial Review: 6/28/2022 12:00:00 AM

Title: Most Post-Stroke Depression Still Goes Untreated
Category: Health News
Created: 7/25/2022 12:00:00 AM
Last Editorial Review: 7/25/2022 12:00:00 AM

Extract

We read with great interest the review article by Randerath et al. [1] recently published in the European Respiratory Review. We would like to congratulate the authors on this clearly structured review, which emphasises the urgent need for an increasingly differentiated view of central sleep apnoea (CSA) in the context of precision medicine.

Background

People living with serious respiratory illness experience a high burden of symptoms. This review aimed to determine whether multicomponent services reduce symptoms in people with serious illness related to respiratory disease.

Retrotransposable elements (RTEs) are common mobile genetic elements comprising ~42% of the human genome. RTEs play critical roles in gene regulation and function, but how they are specifically involved in complex diseases is largely unknown. Here, we investigate the cellular heterogeneity of RTEs using 12 single-cell transcriptome profiles covering three neurodegenerative diseases, Alzheimer's disease (AD), Parkinson's disease, and multiple sclerosis. We identify cell type marker RTEs in neurons, astrocytes, oligodendrocytes, and oligodendrocyte precursor cells that are related to these diseases. The differential expression analysis reveals the landscape of dysregulated RTE expression, especially L1s, in excitatory neurons of multiple neurodegenerative diseases. Machine learning algorithms for predicting cell disease stage using a combination of RTE and gene expression features suggests dynamic regulation of RTEs in AD. Furthermore, we construct a single-cell atlas of retrotransposable elements in neurodegenerative disease (scARE) using these data sets and features. scARE has six feature analysis modules to explore RTE dynamics in a user-defined condition. To our knowledge, scARE represents the first systematic investigation of RTE dynamics at the single-cell level within the context of neurodegenerative diseases.

The COVID-19 pandemic has highlighted the critical role of genomic surveillance for guiding policy and control. Timeliness is key, but sequence alignment and phylogeny slow most surveillance techniques. Millions of SARS-CoV-2 genomes have been assembled. Phylogenetic methods are ill equipped to handle this sheer scale. We introduce a pangenomic measure that examines the information diversity of a k-mer library drawn from a country's complete set of clinical, pooled, or wastewater sequence. Quantifying diversity is central to ecology. Hill numbers, or the effective number of species in a sample, provide a simple metric for comparing species diversity across environments. The more diverse the sample, the higher the Hill number. We adopt this ecological approach and consider each k-mer an individual and each genome a transect in the pangenome of the species. Structured in this way, Hill numbers summarize the temporal trajectory of pandemic variants, collapsing each day's assemblies into genome equivalents. For pooled or wastewater sequence, we instead compare days using survey sequence divorced from individual infections. Across data from the UK, USA, and South Africa, we trace the ascendance of new variants of concern as they emerge in local populations well before these variants are named and added to phylogenetic databases. Using data from San Diego wastewater, we monitor these same population changes from raw, unassembled sequence. This history of emerging variants senses all available data as it is sequenced, intimating variant sweeps to dominance or declines to extinction at the leading edge of the COVID-19 pandemic.

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.

The poly(A) signal, together with auxiliary elements, directs cleavage of a pre-mRNA and thus determines the 3' end of the mature transcript. In many species, including humans, the poly(A) signal is an AAUAAA hexamer, but we recently found that the deeply branching eukaryote Giardia lamblia uses a distinct hexamer (AGURAA) and lacks any known auxiliary elements. Our discovery prompted us to explore the evolutionary dynamics of poly(A) signals and auxiliary elements in the eukaryotic kingdom. We use direct RNA sequencing to determine poly(A) signals for four protists within the Metamonada clade (which also contains G. lamblia) and two outgroup protists. These experiments reveal that the AAUAAA hexamer serves as the poly(A) signal in at least four different eukaryotic clades, indicating that it is likely the ancestral signal, whereas the unusual Giardia version is derived. We find that the use and relative strengths of auxiliary elements are also plastic; in fact, within Metamonada, species like G. lamblia make use of a previously unrecognized auxiliary element where nucleotides flanking the poly(A) signal itself specify genuine cleavage sites. Thus, despite the fundamental nature of pre-mRNA cleavage for the expression of all protein-coding genes, the motifs controlling this process are dynamic on evolutionary timescales, providing motivation for future biochemical and structural studies as well as new therapeutic angles to target eukaryotic pathogens.

Without compromising accuracy, point of care testing (POCT) provides immediate results at the time of in person patient consultation. The purpose of this study was to evaluate time until therapeutic intervention with POCT HbA1c versus venipuncture, where venipuncture was considered standard of care.

The primary outcome was time (hours) to implementation of a therapeutic intervention based on POCT HbA1c result, as compared with most recent venipuncture HbA1c before the study and its associated therapeutic intervention. A total of 94 POCT HbA1c tests were included in the primary analysis.

For the POCT HbA1c, the mean time to therapeutic intervention was 1.6 ± 3.14 hours. For the previous venipuncture HbA1c, the mean time to therapeutic intervention was 1376.66 ± 3356.6 hours (P < .001). Overall, this trial showed that POCT HbA1c results in a significantly faster time to therapeutic intervention than venipuncture in a primary care clinic that serves a rural population.

The rising obesity epidemic is a phenomenon that has gained increasing attention from health providers and health policy makers. This led to recognition of nonalcoholic fatty liver disease (MASLD). The standard for its assessment has been histologic, which is neither practical nor acceptable by patients. Subsequently, a number of noninvasive assessment methods have been developed. However, despite ease of implementation, their confounding variables do hinder their accuracy. Nonetheless, the development of the liver stiffness measurement (LSM) and incorporation of other biological parameters has minimized but not eliminated the need for liver biopsy. Imaging methods are useful in evaluation, estimation, and following the progression of steatosis and fibrosis with particular attention to controlled attenuation parameter (CAP) and MRI–Proton Density Fat Fraction (MRI-PDFF). The choices for the family physician are broad and rely on tests’ availability, cost, and patient acceptance. Great efforts have been undertaken to produce more robust and novel noninvasive markers that indicate fibrinogenesis directly in an implementable and cost-effective way.

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.

Purpose:

Colorectal cancer (CRC) screening is recommended starting at age 45, but there has been little research on strategies to promote screening among patients younger than 50. This study assessed the effect of a multicomponent intervention on screening completion in this age group.

BACKGROUND:Beneficial effects of breathing at FIO2 < 0.21 on disease outcomes have been reported in previous preclinical and clinical studies. However, the safety and intra-hospital feasibility of breathing hypoxic gas for 5 d have not been established. In this study, we examined the physiologic effects of breathing a gas mixture with FIO2 as low as 0.11 in 5 healthy volunteers.METHODS:All 5 subjects completed the study, spending 5 consecutive days in a hypoxic tent, where the ambient oxygen level was lowered in a stepwise manner over 5 d, from FIO2 of 0.16 on the first day to FIO2 of 0.11 on the fifth day of the study. All the subjects returned to an environment at room air on the sixth day. The subjects' SpO2, heart rate, and breathing frequency were continuously recorded, along with daily blood sampling, neurologic evaluations, transthoracic echocardiography, and mental status assessments.RESULTS:Breathing hypoxia concentration dependently caused profound physiologic changes, including decreased SpO2 and increased heart rate. At FIO2 of 0.14, the mean SpO2 was 92%; at FIO2 of 0.13, the mean SpO2 was 93%; at FIO2 of 0.12, the mean SpO2 was 88%; at FIO2 of 0.11, the mean SpO2 was 85%; and, finally, at an FIO2 of 0.21, the mean SpO2 was 98%. These changes were accompanied by increased erythropoietin levels and reticulocyte counts in blood. All 5 subjects concluded the study with no adverse events. No subjects exhibited signs of mental status changes or pulmonary hypertension.CONCLUSIONS:Results of the current physiologic study suggests that, within a hospital setting, delivering FIO2 as low as 0.11 is feasible and safe in healthy subjects, and provides the foundation for future studies in which therapeutic effects of hypoxia breathing are tested.

BACKGROUND:The use of prone position (PP) has been widespread during the COVID-19 pandemic. Whereas it has demonstrated benefits, including improved oxygenation and lung aeration, the factors influencing the response in terms of gas exchange to PP remain unclear. In particular, the association between baseline quantitative computed tomography (CT) scan results and gas exchange response to PP in invasively ventilated subjects with COVID-19 ARDS is unknown. The present study aimed to compare baseline quantitative CT results between subjects responding to PP in terms of oxygenation or CO2 clearance and those who did not.METHODS:This was a single-center, retrospective observational study including critically ill, invasively ventilated subjects with COVID-19–related ARDS admitted to the ICUs of Niguarda Hospital between March 2020–November 2021. Blood gas samples were collected before and after PP. Subjects in whom the PaO2/FIO2 increase was ≥ 20 mm Hg after PP were defined as oxygen responders. CO2 responders were defined when the ventilatory ratio (VR) decreased during PP. Automated quantitative CT analyses were performed to obtain tissue mass and density of the lungs.RESULTS:One hundred twenty-five subjects were enrolled, of which 116 (93%) were O2 responders and 51 (41%) CO2 responders. No difference in quantitative CT characteristics and oxygen were observed between responders and non-responders (tissue mass 1,532 ± 396 g vs 1,654 ± 304 g, P = .28; density −544 ± 109 HU vs −562 ± 58 HU P = .42). Similar findings were observed when dividing the population according to CO2 response (tissue mass 1,551 ± 412 g vs 1,534 ± 377 g, P = .89; density −545 ± 123 HU vs −546 ± 94 HU, P = .99).CONCLUSIONS:Most subjects with COVID-19–related ARDS improved their oxygenation at the first pronation cycle. The study suggests that baseline quantitative CT scan data were not associated with the response to PP in oxygenation or CO2 in mechanically ventilated subjects with COVID-19–related ARDS.

BACKGROUND:Post–COVID-19 syndrome has affected millions of people, with rehabilitation being at the center of non-pharmacologic care. However, numerous published studies show conflicting results due to, among other factors, considerable variation in subject characteristics. Currently, the effects of age, sex, time of implementation, and prior disease severity on the outcomes of a supervised rehabilitation program after COVID-19 remain unknown.METHODS:This was a non-randomized case-control study. Subjects with post–COVID-19 sequelae were enrolled. Among study participants, those who could attend an 8-week, supervised rehabilitation program composed the intervention group, whereas those who couldn’t the control group. Measurements were collected at baseline and 8 weeks thereafter.RESULTS:Study groups (N = 119) had similar baseline measurements. Participation in rehabilitation (n = 47) was associated with clinically important improvements in the 6-min walk test (6MWT) distance, adjusted (for potential confounders) odds ratio (AOR) 4.56 (95% CI 1.95–10.66); 1-min sit-to-stand test, AOR 4.64 (1.88-11.48); Short Physical Performance Battery, AOR 7.93 (2.82–22.26); health-related quality of life (HRQOL) 5-level EuroQol-5D (Visual Analog Scale), AOR 3.12 (1.37–7.08); Montreal Cognitive Assessment, AOR 6.25 (2.16–18.04); International Physical Activity Questionnaire, AOR 3.63 (1.53–8.59); Fatigue Severity Scale, AOR 4.07 (1.51–10.98); Chalder Fatigue Scale (bimodal score), AOR 3.33 (1.45–7.67); Modified Medical Research Council dyspnea scale (mMRC), AOR 4.43 (1.83–10.74); Post–COVID-19 Functional Scale (PCFS), AOR 3.46 (1.51–7.95); and COPD Assessment Test, AOR 7.40 (2.92–18.75). Time from disease onset was marginally associated only with 6MWT distance, AOR 0.99 (0.99–1.00). Prior hospitalization was associated with clinically important improvements in the mMRC dyspnea scale, AOR 3.50 (1.06–11.51); and PCFS, AOR 3.42 (1.16–10.06). Age, sex, and ICU admission were not associated with the results of any of the aforementioned tests/grading scales.CONCLUSIONS:In this non-randomized, case-control study, post–COVID-19 rehabilitation was associated with improvements in physical function, activity, HRQOL, respiratory symptoms, fatigue, and cognitive impairment. These associations were observed independently of timing of rehabilitation, age, sex, prior hospitalization, and ICU admission.

Purpose The posterior superior alveolar (PSA) block injection is one of many techniques used to provide profound anesthesia for invasive dental procedures. This technique has a high success rate but is not without complication risks. The purpose of this study was to determine if pulpal anesthesia of the maxillary second molar could be achieved using a reduced needle depth of 10mm or 5mm compared to the traditional needle depth of 16mm.Methods Sixty participants were asked to participate in three sessions. Each session started with a pre neural response test, followed by one randomized needle depth PSA injection, and ending with a post neural response test. The neural response test consisted of two parts, a cold refrigerant and a dental probe, on the buccal and interproximal surface of the maxillary second molar. After receiving a positive neural response, each participant received a posterior superior alveolar block injection using a short (21mm), 27-gauge dental needle with a randomized needle penetration depth of 16mm, 10mm, or 5mm. A post neural response test consisting of the same two parts as the pre-test was conducted on the maxillary second molar to evaluate for profound anesthesia.Results Positive neural responses were obtained from 100% of the participants (n=167) during the pre-tests. Study results demonstrated an 85% success rate at the traditional 16mm needle depth and a 93% and 92% success rates for the reduced needle depths of 10mm and 5mm, respectively. Pulpal anesthesia of the maxillary second molar had been achieved at all three needle depths with no statistically significant difference in the rate of success. Furthermore, there were no adverse events observed.Conclusion The reduced needle depth technique showed promise in achieving desired results of pulpal anesthesia with a reduced risk for complications associated with the PSA block injection. Additional studies are recommended to achieve evidence-based support for this reduced needle depth technique.

Obidoxime chloride is an antidote for nerve gas intoxication. As an emergency medicine, it is being stored by the Israel Defense Forces (IDF) scattered throughout Israel in depots without a controlled environment (field conditions), thus being exposed to high and fluctuating temperatures. These conditions do not meet the manufacturer’s requirements. In addition, due to possible supply shortages, the utilization of expired batches was suggested. The current work investigated these matters. Long-term (15 years) storage under different conditions was initiated. Chemical stability and toxicity in rats were assessed. No difference was found between field conditions vs the controlled environment. The obidoxime assay remained >95% for 5 years and >90% for 7 years. The pH remained above the lower specification limit for 7–8 years. The major degradation product, 4-pyridinealdoxime, surpassed the allowed limit at 5 years. The content of total unknown impurities reached its maximum allowed by the IDF limit at 4–5 years. Threefold higher than clinically utilized doses of valid-to-date Toxogonin batches administered to rats did not cause any abnormality. However, expired batches produced significant toxic effects. Although no difference was found between storage of obidoxime ampoules when adhering to manufacturer’s recommendations vs field conditions, accumulation of degradants over the limit allowed by the IDF at 4–5 years of storage and the toxicity of the expired batches observed in rats led the IDF to a decision to shorten the shelf-life of this product from 5 to 4 years when stored in an uncontrolled environment of the Mediterranean climate.

During B-cell development, cells progress through multiple developmental stages, with the pro-B-cell stage defining commitment to the B-cell lineage. YY1 is a ubiquitous transcription factor that is capable of both activation and repression functions. We found here that knockout of YY1 at the pro-B-cell stage eliminates B lineage commitment. YY1 knockout pro-B cells can generate T lineage cells in vitro using the OP9-DL4 feeder system and in vivo after injection into sublethally irradiated Rag1^–/– mice. These T lineage-like cells lose their B lineage transcript profile and gain a T-cell lineage profile. Single-cell RNA-seq experiments showed that as YY1 knockout pro-B cells transition into T lineage cells in vitro, various cell clusters adopt transcript profiles representing a multiplicity of hematopoietic lineages, indicating unusual lineage plasticity. In addition, YY1 KO pro-B cells in vivo can give rise to other hematopoietic lineages in vivo. Evaluation of RNA-seq, scRNA-seq, ChIP-seq, and scATAC-seq data indicates that YY1 controls numerous chromatin-modifying proteins leading to increased accessibility of alternative lineage genes in YY1 knockout pro-B cells. Given the ubiquitous nature of YY1 and its dual activation and repression functions, YY1 may regulate commitment in multiple cell lineages.

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.

Solid tumors that arise in the body interact with neurons, which influences cancer progression and treatment response. Here, we discuss key questions in the field, including defining the nature of interactions between tumors and neural circuits and defining how neural signals shape the tumor microenvironment. This information will allow us to optimally target neural signaling to improve outcomes for cancer patients.

Thermoregulation, responsible for maintaining a stable core temperature during wide fluctuations in external and internal thermal environments, is an iconic homeostatic process. However, we suggest that despite its fundamental physiological significance, the potential for required cool housing temperatures and thermoregulatory mechanisms to influence the interpretation of experimental data is not sufficiently appreciated. Moreover, although it is generally assumed that the major thermoregulatory pathways are well understood, here we discuss new research that suggests otherwise and reveals the emergence of a new wave of exciting ideas for this "old" field of research.

Recent work has highlighted the central role the brain–body axis plays in not only maintaining organismal homeostasis but also coordinating the body's response to immune and inflammatory insults. Here, we discuss how science is poised to address the many ways that our brain is directly involved with disease. In particular, we feel that combining cutting-edge tools in neuroscience with translationally relevant models of cancer will be critical to understanding how the brain and tumors communicate and modulate each other's behavior.

The brain's capacity to predict and anticipate changes in internal and external environments is fundamental to initiating efficient adaptive responses, behaviors, and reflexes that minimize disruptions to physiology. In the context of feeding control, the brain predicts and anticipates responses to the consumption of dietary substances, thus driving adaptive behaviors in the form of food choices, physiological preparation for meals, and engagement of defensive mechanisms. Here, we provide an integrative perspective on the multisensory computation between exteroceptive and interoceptive cues that guides feeding strategy and may result in food-related disorders.

Neural reflexes occupy a central role in physiological homeostasis. The vagus nerve is a major conduit for transmitting afferent and efferent signals in homeostatic reflex arcs between the body and the brain. Recent advances in neuroscience, immunology, and physiology have revealed important vagus nerve mechanisms in suppressing inflammation and treating rheumatoid arthritis and other autoimmune conditions. Numerous clinical trials indicate that there is significant benefit to vagus nerve stimulation therapy. Although many questions are still unanswered, it will be important, even necessary, to pursue answers that will be useful in guiding interventions to modulate immunological and physiological homeostasis.

The world of cancer science is moving toward a paradigm shift in making connections with neuroscience. After decades of research on genetic instability and mutations or on the tumor microenvironment, emerging evidence suggests that a malignant tumor is able to hijack and use the brain and its network of peripheral and central neurons as disrupters of homeostasis in the body. Whole-body homeostasis requires brain–body circuits to maintain survival and health via the processes of interoception, immunoception, and nociception. It is now likely that cancer disturbs physiological brain–body communication in making bidirectional brain tumor connections.

The study of biological mechanisms, while crucial, cannot fully explain complex phenomena like the instinct to eat. The mind–body connection, as exemplified by the concept of "voodoo death," highlights the profound influence of belief and cultural context on physiology. Indigenous knowledge systems further emphasize the interconnectedness of humans with their environment. Recent discoveries in gut–brain communication reveal the intricate neural circuits that drive our visceral desires, but a holistic approach that integrates both physiological mechanisms and the subjective experience of life, informed by diverse cultural perspectives, will be essential to truly understand what it means to be alive.

The dorsal vagal complex contains three structures: the area postrema, the nucleus tractus solitarii, and the dorsal motor nucleus of the vagus. These structures are tightly linked, both anatomically and functionally, and have important yet distinct roles in not only conveying peripheral bodily signals to the rest of the brain but in the generation of behavioral and physiological responses. Reports on the new discoveries in these structures were highlights of the symposium. In this outlook, we focus on the roles of the area postrema in mediating brain–body interactions and its potential utility as a therapeutic target, especially in cancer cachexia.

Our approaches toward understanding cancer have evolved beyond cell-intrinsic and local microenvironmental changes within the tumor to encompass how the cancer interfaces with the entire host organism. The nervous system is uniquely situated at the interface between the brain and body, constantly receiving and sending signals back and forth to maintain homeostasis and respond to salient stimuli. It is becoming clear that various cancers disrupt this dialog between the brain and body via both neuronal and humoral routes, leading to aberrant brain activity and accelerated disease. In this outlook, I discuss this view of cancer as a homeostatic challenge, emphasize cutting-edge work, and provide outstanding questions that need to be answered to move the field forward.

Memory formation is contingent on molecular and structural changes in neurons in response to learning stimuli—a process known as neuronal plasticity. The initiation step of mRNA translation is a gatekeeper of long-term memory by controlling the production of plasticity-related proteins in the brain. The mechanistic target of rapamycin complex 1 (mTORC1) controls mRNA translation, mainly through phosphorylation of the eukaryotic initiation factor 4E (eIF4E)-binding proteins (4E-BPs) and ribosomal protein S6 kinases (S6Ks). mTORC1 signaling decreases throughout brain development, starting from the early postnatal period. Here, we discovered that in mice, the age-dependent decrease in mTORC1 signaling occurs selectively in excitatory but not inhibitory neurons. Using a gene conditional knockout (cKO) strategy, we demonstrate that either up- or downregulating the mTORC1-4E-BP2 axis in GAD65 inhibitory interneurons, but not excitatory neurons, results in long-term object recognition and object location memory deficits. Our data indicate that the mTORC1 pathway in inhibitory but not excitatory neurons plays a key role in memory formation.

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.

Bacterial regulatory RNAs (sRNAs) are important players to control gene expression. In Staphylococcus aureus, SprC is an antivirulent trans-acting sRNA known to base-pair with the major autolysin atl mRNA, preventing its translation. Using MS2-affinity purification coupled with RNA sequencing, we looked for its sRNA-RNA interactome and identified 14 novel mRNA targets. In vitro biochemical investigations revealed that SprC binds two of them, czrB and deoD, and uses a single accessible region to regulate its targets, including Atl translation. Unlike Atl regulation, the characterization of the SprC-czrB interaction pinpointed a destabilization of the czrAB cotranscript, leading to a decrease of the mRNA level that impaired CzrB zinc efflux pump expression. On a physiological standpoint, we showed that SprC expression is detrimental to combat against zinc toxicity. In addition, phagocyctosis assays revealed a significant, but moderate, increase of czrB mRNA levels in a sprC-deleted mutant, indicating a functional link between SprC and czrB upon internalization in macrophages, and suggesting a role in resistance to both oxidative and zinc bursts. Altogether, our data uncover a novel pathway in which SprC is implicated, highlighting the multiple strategies used by S. aureus to balance virulence using an RNA regulator.

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.

Background

The real-world consequences of a Philips Respironics recall for positive airway pressure (PAP) devices distributed between 2009 and 2021 are unknown.

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 (K_i) 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 K_i 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.

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 (K_m) 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.

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.

Compound probiotics have been widely used and commonly coadministered with other drugs for treating various chronic illnesses, yet their effects on drug pharmacokinetics remain underexplored. This study elucidated the impact of VSL#3 on the metabolism of probe drugs for cytochrome P450 enzymes (P450s), specifically omeprazole, tolbutamide, midazolam, metoprolol, phenacetin, and chlorzoxazone. Male Wistar rats were administered drinking water containing VSL#3 or not for 14 days and then intragastrically administered a P450 probe cocktail; this was done to investigate the host P450’s metabolic phenotype. Stool, liver/jejunum, and serum samples were collected for 16S ribosomal RNA sequencing, RNA sequencing, and bile acid profiling. The results indicated significant differences in both α and β diversity of intestinal microbial composition between the probiotic and vehicle groups in rats. In the probiotic group, the bioavailability of omeprazole increased by 269.9%, whereas those of tolbutamide and chlorpropamide decreased by 28.1% and 27.4%, respectively. The liver and jejunum exhibited 1417 and 4004 differentially expressed genes, respectively, between the two groups. In the probiotic group, most of P450 genes were upregulated in the liver but downregulated in the jejunum. The expression of genes encoding metabolic enzymes and drug transporters also changed. The serum-conjugated bile acids in the probiotic group were significantly reduced. Shorter duodenal villi and longer ileal villi were found in the probiotic group. In summary, VSL#3 administration altered the gut microbiota, host drug–processing gene expression, and intestinal structure in rats, which could be reasons for pharmacokinetic changes.

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.