ee

A Phenotypic Screen Identifies Calcium Overload as a Key Mechanism of {beta}-Cell Glucolipotoxicity

Type 2 diabetes (T2D) is caused by loss of pancreatic β-cell mass and failure of the remaining β-cells to deliver sufficient insulin to meet demand. β-Cell glucolipotoxicity (GLT), which refers to combined, deleterious effects of elevated glucose and fatty acid levels on β-cell function and survival, contributes to T2D-associated β-cell failure. Drugs and mechanisms that protect β-cells from GLT stress could potentially improve metabolic control in patients with T2D. In a phenotypic screen seeking low-molecular-weight compounds that protected β-cells from GLT, we identified compound A that selectively blocked GLT-induced apoptosis in rat insulinoma cells. Compound A and its optimized analogs also improved viability and function in primary rat and human islets under GLT. We discovered that compound A analogs decreased GLT-induced cytosolic calcium influx in islet cells, and all measured β-cell–protective effects correlated with this activity. Further studies revealed that the active compound from this series largely reversed GLT-induced global transcriptional changes. Our results suggest that taming cytosolic calcium overload in pancreatic islets can improve β-cell survival and function under GLT stress and thus could be an effective strategy for T2D treatment.




ee

Improving mental health in autistic young adults: a qualitative study exploring help-seeking barriers in UK primary care

BackgroundAutistic people are at increased risk of developing mental health problems. To reduce the negative impact of living with autism in a non-autistic world, efforts to improve take-up and access to care, and support in early years, which will typically start with a GP appointment, must be grounded in the accounts of autistic young adults.AimTo explore how autistic young adults understand and manage mental health problems; and to consider help seeking as a focus.Design and settingA cross-sectional, qualitative study. Autistic participants were purposively selected to represent a range of mental health conditions including anxiety and depression. A subsample were recruited from a population cohort screened for autism in childhood. The study concerns access to primary care.MethodNineteen autistic young adults without learning disabilities, aged 23 or 24 years, were recruited. In-depth, semi-structured interviews explored how they understood and managed mental health problems. Data were analysed thematically.ResultsYoung adults preferred self-management strategies. Multiple factors contributed to a focus on self-management, including: beliefs about the aetiology of mental health difficulties and increased vulnerability with the context of a diagnosis of autism, knowledge of self-management, and a view that formal support was unavailable or inadequate. Families had limited awareness of professional support.ConclusionYoung autistic adults without learning disabilities, and their families, may hold erroneous beliefs about autism and mental health. This may affect help seeking and contribute to an exacerbation of symptoms. GPs need to be alert to the fact that autistic young adults in their care may be experiencing mental health difficulties but may not recognise them as such.




ee

Connecting General Practitioners Through a Peer-Facilitated Community of Practice for Chronic Disease Care [Innovations in Primary Care]




ee

Caring for Rohingya Refugees With Diphtheria and Measles: On the Ethics of Humanity [Reflections]

Hundreds of thousands of Rohingya refugees arrived in Bangladesh within weeks in fall 2017, quickly forming large settlements without any basic support. Humanitarian first responders provided basic necessities including food, shelter, water, sanitation, and health care. However, the challenge before them—a vast camp ravaged by diphtheria and measles superimposed on a myriad of common pathologies—was disproportionate to the resources. The needs were endless, resources finite, inadequacies abundant, and premature death inevitable. While such confines force unimaginable choices in resource allocation, they do not define the humanitarian purpose—to alleviate suffering and not allow such moral violations to become devoid of their horrifying meaning. As humanitarian workers, we maintain humanity when we care, commit, and respond to moral injustices. This refusal to abandon others in desperate situations is an attempt to rectify injustices through witnessing and solidarity. When people are left behind, we must not leave them alone.




ee

On the Frontline of the COVID-19 Outbreak: Keeping Patients on Long-Term Dialysis Safe




ee

Prebiotics Inhibit Proteolysis by Gut Bacteria in a Host Diet-Dependent Manner: a Three-Stage Continuous In Vitro Gut Model Experiment [Food Microbiology]

Dietary protein residue can result in microbial generation of various toxic metabolites in the gut, such as ammonia. A prebiotic is "a substrate that is selectively utilised by host microorganisms conferring a health benefit" (G. R. Gibson, R. Hutkins, M. E. Sanders, S. L. Prescott, et al., Nat Rev Gastroenterol Hepatol 14:491–502, 2017, https://doi.org/10.1038/nrgastro.2017.75). Prebiotics are carbohydrates that may have the potential to reverse the harmful effects of gut bacterial protein fermentation. Three-stage continuous colonic model systems were inoculated with fecal samples from omnivore and vegetarian volunteers. Casein (equivalent to 105 g protein consumption per day) was used within the systems as a protein source. Two different doses of inulin-type fructans (Synergy1) were later added (equivalent to 10 g per day in vivo and 15 g per day) to assess whether this influenced protein fermentation. Bacteria were enumerated by fluorescence in situ hybridization with flow cytometry. Metabolites from bacterial fermentation (short-chain fatty acid [SCFA], ammonia, phenol, indole, and p-cresol) were monitored to further analyze proteolysis and the prebiotic effect. A significantly higher number of bifidobacteria was observed with the addition of inulin together with reduction of Desulfovibrio spp. Furthermore, metabolites from protein fermentation, such as branched-chain fatty acids (BCFA) and ammonia, were significantly lowered with Synergy1. Production of p-cresol varied among donors, as we recognized four high producing models and two low producing models. Prebiotic addition reduced its production only in vegetarian high p-cresol producers.

IMPORTANCE Dietary protein levels are generally higher in Western populations than in the world average. We challenged three-stage continuous colonic model systems containing high protein levels and confirmed the production of potentially harmful metabolites from proteolysis, especially replicates of the transverse and distal colon. Fermentations of proteins with a prebiotic supplementation resulted in a change in the human gut microbiota and inhibited the production of some proteolytic metabolites. Moreover, we observed both bacterial and metabolic differences between fecal bacteria from omnivore donors and vegetarian donors. Proteins with prebiotic supplementation showed higher Bacteroides spp. and inhibited Clostridium cluster IX in omnivore models, while in vegetarian modes, Clostridium cluster IX was higher and Bacteroides spp. lower with high protein plus prebiotic supplementation. Synergy1 addition inhibited p-cresol production in vegetarian high p-cresol-producing models while the inhibitory effect was not seen in omnivore models.




ee

Vib-PT, an Aromatic Prenyltransferase Involved in the Biosynthesis of Vibralactone from Stereum vibrans [Enzymology and Protein Engineering]

Vibralactone, a hybrid compound derived from phenols and a prenyl group, is a strong pancreatic lipase inhibitor with a rare fused bicyclic β-lactone skeleton. Recently, a researcher reported a vibralactone derivative (compound C1) that caused inhibition of pancreatic lipase with a half-maximal inhibitory concentration of 14 nM determined by structure-based optimization, suggesting a potential candidate as a new antiobesity treatment. In the present study, we sought to identify the main gene encoding prenyltransferase in Stereum vibrans, which is responsible for the prenylation of phenol leading to vibralactone synthesis. Two RNA silencing transformants of the identified gene (vib-PT) were obtained through Agrobacterium tumefaciens-mediated transformation. Compared to wild-type strains, the transformants showed a decrease in vib-PT expression ranging from 11.0 to 56.0% at 5, 10, and 15 days in reverse transcription-quantitative PCR analysis, along with a reduction in primary vibralactone production of 37 to 64% at 15 and 21 days, respectively, as determined using ultra-high-performance liquid chromatography-mass spectrometry analysis. A soluble and enzymatically active fusion Vib-PT protein was obtained by expressing vib-PT in Escherichia coli, and the enzyme’s optimal reaction conditions and catalytic efficiency (Km/kcat) were determined. In vitro experiments established that Vib-PT catalyzed the C-prenylation at C-3 of 4-hydroxy-benzaldehyde and the O-prenylation at the 4-hydroxy of 4-hydroxy-benzenemethanol in the presence of dimethylallyl diphosphate. Moreover, Vib-PT shows promiscuity toward aromatic compounds and prenyl donors.

IMPORTANCE Vibralactone is a lead compound with a novel skeleton structure that shows strong inhibitory activity against pancreatic lipase. Vibralactone is not encoded by the genome directly but rather is synthesized from phenol, followed by prenylation and other enzyme reactions. Here, we used an RNA silencing approach to identify and characterize a prenyltransferase in a basidiomycete species that is responsible for the synthesis of vibralactone. The identified gene, vib-PT, was expressed in Escherichia coli to obtain a soluble and enzymatically active fusion Vib-PT protein. In vitro characterization of the enzyme demonstrated the catalytic mechanism of prenylation and broad substrate range for different aromatic acceptors and prenyl donors. These characteristics highlight the possibility of Vib-PT to generate prenylated derivatives of aromatics and other compounds as improved bioactive agents or potential prodrugs.




ee

Two Functional Fatty Acyl Coenzyme A Ligases Affect Free Fatty Acid Metabolism To Block Biosynthesis of an Antifungal Antibiotic in Lysobacter enzymogenes [Environmental Microbiology]

In Lysobacter enzymogenes OH11, RpfB1 and RpfB2 were predicted to encode acyl coenzyme A (CoA) ligases. RpfB1 is located in the Rpf gene cluster. Interestingly, we found an RpfB1 homolog (RpfB2) outside this canonical gene cluster, and nothing is known about its functionality or mechanism. Here, we report that rpfB1 and rpfB2 can functionally replace EcFadD in the Escherichia coli fadD mutant JW1794. RpfB activates long-chain fatty acids (n-C16:0 and n-C18:0) for the corresponding fatty acyl-CoA ligase (FCL) activity in vitro, and Glu-361 plays critical roles in the catalytic mechanism of RpfB1 and RpfB2. Deletion of rpfB1 and rpfB2 resulted in significantly increased heat-stable antifungal factor (HSAF) production, and overexpression of rpfB1 or rpfB2 completely suppressed HSAF production. Deletion of rpfB1 and rpfB2 resulted in increased L. enzymogenes diffusible signaling factor 3 (LeDSF3) synthesis in L. enzymogenes. Overall, our results showed that changes in intracellular free fatty acid levels significantly altered HSAF production. Our report shows that intracellular free fatty acids are required for HSAF production and that RpfB affects HSAF production via FCL activity. The global transcriptional regulator Clp directly regulated the expression of rpfB1 and rpfB2. In conclusion, these findings reveal new roles of RpfB in antibiotic biosynthesis in L. enzymogenes.

IMPORTANCE Understanding the biosynthetic and regulatory mechanisms of heat-stable antifungal factor (HSAF) could improve the yield in Lysobacter enzymogenes. Here, we report that RpfB1 and RpfB2 encode acyl coenzyme A (CoA) ligases. Our research shows that RpfB1 and RpfB2 affect free fatty acid metabolism via fatty acyl-CoA ligase (FCL) activity to reduce the substrate for HSAF synthesis and, thereby, block HSAF production in L. enzymogenes. Furthermore, these findings reveal new roles for the fatty acyl-CoA ligases RpfB1 and RpfB2 in antibiotic biosynthesis in L. enzymogenes. Importantly, the novelty of this work is the finding that RpfB2 lies outside the Rpf gene cluster and plays a key role in HSAF production, which has not been reported in other diffusible signaling factor (DSF)/Rpf-producing bacteria.




ee

Microbial Diversity in Deep-Subsurface Hot Brines of Northwest Poland: from Community Structure to Isolate Characteristics [Geomicrobiology]

Deep-subsurface hot brines in northwest Poland, extracted through boreholes reaching 1.6 and 2.6 km below the ground surface, were microbiologically investigated using culture-independent and culture-dependent methods. The high-throughput sequencing of 16S rRNA gene amplicons showed a very low diversity of bacterial communities, which were dominated by phyla Proteobacteria and Firmicutes. Bacterial genera potentially involved in sulfur oxidation and nitrate reduction (Halothiobacillus and Methylobacterium) prevailed in both waters over the sulfate reducers ("Candidatus Desulforudis" and Desulfotomaculum). Only one archaeal taxon, affiliated with the order Thermoplasmatales, was detected in analyzed samples. Bacterial isolates obtained from these deep hot brines were closely related to Bacillus paralicheniformis based on the 16S rRNA sequence similarity. However, genomic and physiological analyses made for one of the isolates, Bacillus paralicheniformis strain TS6, revealed the existence of more diverse metabolic pathways than those of its moderate-temperature counterpart. These specific traits may be associated with the ecological adaptations to the extreme habitat, which suggest that some lineages of B. paralicheniformis are halothermophilic.

IMPORTANCE Deep-subsurface aquifers, buried thousands of meters down the Earth’s crust, belong to the most underexplored microbial habitats. Although a few studies revealed the existence of microbial life at the depths, the knowledge about the microbial life in the deep hydrosphere is still scarce due to the limited access to such environments. Studying the subsurface microbiome provides unique information on microbial diversity, community structure, and geomicrobiological processes occurring under extreme conditions of the deep subsurface. Our study shows that low-diversity microbial assemblages in subsurface hot brines were dominated by the bacteria involved in biogeochemical cycles of sulfur and nitrogen. Based on genomic and physiological analyses, we found that the Bacillus paralicheniformis isolate obtained from the brine under study differed from the mesophilic species in the presence of specific adaptations to harsh environmental conditions. We indicate that some lineages of B. paralicheniformis are halothermophilic, which was not previously reported.




ee

Association between media attention and presentation of vaccination information on Canadian chiropractors websites: a prospective mixed-methods cohort study

Background:

Historically, some chiropractors have been critical of vaccination, and this has been the subject of recent media attention in Canada. We explored the association between media attention and public dissemination of vaccination information on Canadian chiropractors’ websites.

Methods:

In 2016, we identified all Canadian chiropractors’ websites that provided information on vaccination by extracting details from the regulatory college website for each province using the search engine on their "find a chiropractor" page. We assessed the quality of information using the Web Resource Rating Tool (scores range from 0% [worst] to 100% [best]), determined whether vaccination was portrayed in a positive, neutral or negative manner, and conducted thematic analysis of vaccination content. We revisited all identified websites in 2019 to explore for changes to posted vaccination material.

Results:

In July 2016, of 3733 chiropractic websites identified, 94 unique websites provided information on vaccination: 59 (63%) gave negative messaging, 19 (20%) were neutral and 16 (17%) were positive. The quality of vaccination content on the websites was generally poor, with a median Web Resource Rating Tool score of 19%. We identified 4 main themes: there are alternatives to vaccination, vaccines are harmful, evidence regarding vaccination and health policy regarding vaccination. From 2012 to 2016, there was 1 Canadian newspaper story concerning antivaccination statements by chiropractors, whereas 51 news articles were published on this topic between 2017 and 2019. In April 2019, 45 (48%) of the 94 websites we had identified in 2016 had removed all vaccination content or had been discontinued.

Interpretation:

In 2016, a minority of Canadian chiropractors provided vaccination information on their websites, the majority of which portrayed vaccination negatively. After substantial national media attention, about half of all vaccination material on chiropractors’ websites was removed within several years.




ee

Palliative care clinical rotations among undergraduate and postgraduate medical trainees in Canada: a descriptive study

Background:

The number of medical undergraduate and postgraduate students completing palliative care clinical rotations in Canadian medical schools is currently unknown. The aim of this study was to assess the proportion of Canadian medical trainees completing clinical rotations in palliative care and to determine whether changes took place between 2008 and 2018.

Methods:

In this descriptive study, all Canadian medical schools (n = 17) were invited to provide data at the undergraduate and postgraduate levels (2007/08–2015/16 and 2007/08–2017/18, respectively). Information collected included the number, type and length of palliative care clinical rotations offered and the total number of medical trainees or residents enrolled at each school.

Results:

All 17 Canadian medical schools responded to the request for information. At the undergraduate level, palliative care clinical rotations were not offered in 2 schools, mandatory in 2 and optional in 13. Three schools that offered optional rotations were unable to provide complete data and were therefore excluded from further analyses. In 2015/16, only 29.7% of undergraduate medical students completed palliative care clinical rotations, yet this was a significant improvement compared to 2011/12 (13.6%, p = 0.02). At the postgraduate level, on average, 57.9% of family medicine trainees completed such rotations between 2007/08 and 2016/17. During the same period, palliative care clinical rotations were completed by trainees in specialty or subspecialty programs in anesthesiology (34.2%), geriatric medicine (64.4%), internal medicine (30.9%), neurology (28.2%) and psychiatry (64.5%).

Interpretation:

Between 2008 and 2018, a large proportion of Canadian medical trainees graduated without the benefit of a clinical rotation in palliative care. Without dedicated clinical exposure to palliative care, many physicians will enter practice without vital palliative care competencies.




ee

Digging Deep in the Microbiome to Diagnose Clostridioides difficile Infection

Clostridioides difficileDiagnosticsMetabolomicsMicrobiome




ee

Emergence of a Novel Coronavirus Disease (COVID-19) and the Importance of Diagnostic Testing: Why Partnership between Clinical Laboratories, Public Health Agencies, and Industry Is Essential to Control the Outbreak




ee

A Yellow-Green Cerebrospinal Fluid Sample

body fluidsCSF




ee

Sailing through the Three Gorges in China

At about 6300 km, Chang Jiang or Long River (长江) is the longest river in Asia and third longest in the world. It is the longest in the world to flow entirely within one country and plays a large role in the history, culture, and economy of China. For thousands of years, the river has been used for water, irrigation, sanitation, transportation, industry, boundary-marking, and war. Passing through 10 provinces, it commences its flow from the Tanggula Mountains (唐古拉山) in ethnic Tibetan Qinghai (青海) Province in northwest China and ends at the East China Sea in Shanghai (上海). Along the middle reaches of the river, between the western upstream Baidi City (白帝城) of Chongqing (重庆) Municipality and Yichang (宜昌) city of Hubei (湖北) Province downstream, the river passes through 3 adjacent gorges, known as the Three Gorges (三峡): Qutang, Wuxia, and Xiling gorge (瞿塘, 巫峡, 西陵峡) cutting through the Wu Mountains (巫山). Spanning a distance of about 120 km, these gorges are noted for their natural beauty: unusual-looking mountain peaks ranging from 800 m to 2000 m, precipitous valleys, dense forest, and spectacular landscape. Many ancient government officials, scholars, poets, and painters visited the Three Gorges and left their impressions and praises in writings. Archeological discoveries in recent years have shown for the first time that the Three Gorges area should be recognized as the birthplace of Chinese civilization.




ee

Can We Improve Current Cancer Screening Programs?

Cancer continues to be one of the leading causes of morbidity and mortality in the US. Although the treatment of cancer has evolved over the past decades with the use of targeted therapies and immunotherapy, many of these new treatments are expensive and are not readily available to everyone. Moreover, the recent success with treatment advances are not generalized to all cancer types, as some cancers continue to be devastating without significant progress in treatment options. Hence, early detection through population screening remains a critical armament against cancer.




ee

Insight into the structure and tasks of the Early Career Members Committee of the European Respiratory Society

The Early Career Members Committee (ECMC) of the European Respiratory Society (ERS) consists of 14 members, one Early Career Member (ECM) representative per assembly. In September 2019, seven recently elected representatives joined the ECMC. An overview is given of the tasks performed by each representative within the ECMC (table 1). In addition, a short summary about the content of these tasks is provided.




ee

Screening and surveillance in respiratory medicine

We are already a couple of months into 2020 and I hope you had a good start to the new year. I wish you, our readers, reviewers, authors and editors, happiness, success and health in this new decade.




ee

Overdiagnosis of lung cancer with low-dose computed tomography screening: meta-analysis of the randomised clinical trials

In low-dose computed tomography (LDCT) screening for lung cancer, all three main conditions for overdiagnosis in cancer screening are present: 1) a reservoir of slowly or nongrowing lung cancer exists; 2) LDCT is a high-resolution imaging technology with the potential to identify this reservoir; and 3) eligible screening participants have a high risk of dying from causes other than lung cancer. The degree of overdiagnosis in cancer screening is most validly estimated in high-quality randomised controlled trials (RCTs), with enough follow-up time after the end of screening to avoid lead-time bias and without contamination of the control group.

Nine RCTs investigating LDCT screening were identified. Two RCTs were excluded because lung cancer incidence after the end of screening was not published. Two other RCTs using active comparators were also excluded. Therefore, five RCTs were included: two trials were at low risk of bias, two of some concern and one at high risk of bias. In a meta-analysis of the two low risk of bias RCTs including 8156 healthy current or former smokers, 49% of the screen-detected cancers were overdiagnosed. There is uncertainty about this substantial degree of overdiagnosis due to unexplained heterogeneity and low precision of the summed estimate across the two trials.

Key points

  • Nine randomised controlled trials (RCTs) on low-dose computed tomography screening were identified; five were included for meta-analysis but only two of those were at low risk of bias.

  • In a meta-analysis of recent low risk of bias RCTs including 8156 healthy current or former smokers from developed countries, we found that 49% of the screen-detected cancers may be overdiagnosed.

  • There is uncertainty about the degree of overdiagnosis in lung cancer screening due to unexplained heterogeneity and low precision of the point estimate.

  • If only high-quality RCTs are included in the meta-analysis, the degree of overdiagnosis is substantial.

  • Educational aims

  • To appreciate that low-dose computed tomography screening for lung cancer meets all three main conditions for overdiagnosis in cancer screening: a reservoir of indolent cancers exists in the population; the screening test is able to "tap" this reservoir by detecting biologically indolent cancers as well as biologically important cancers; and the population being screened is characterised by a relatively high competing risk of death from other causes

  • To learn about biases that might affect the estimates of overdiagnosis in randomised controlled trials in cancer screening




    ee

    Lung cancer: keep your mind open - it's not always the usual suspects!

    Some years ago, I entered a completely unfamiliar world. This was a landscape that clinicians deal with every day but for the individual suspected of having lung cancer, it can appear hostile and scary, often misrepresented by outdated imagery, information and television portrayal. Lung cancer is not awash with celebrities admitting to having it or grand fundraising campaigns like other conditions. Despite many changes in the treatment landscape, it's still generally much more stigmatised than other cancers.




    ee

    Continuous professional development: elevating sleep and breathing disorder education in Europe

    Sleep and breathing disorders are highly prevalent, representing a growing subspecialty of respiratory medicine. The term sleep disordered breathing (SDB) encompasses a range of conditions characterised by abnormal breathing during sleep, from chronic or habitual snoring, to frank obstructive sleep apnoea (OSA) or, in some cases, central sleep apnoea (CSA) and hypoventilation syndromes. OSA is the commonest form of SDB, leading to many potential consequences and adverse clinical outcomes, including excessive daytime sleepiness, impaired daytime function, metabolic dysfunction, and an increased risk of cardiovascular disease and mortality [1]. The estimated reported prevalence of moderate-to-severe SDB (≥15 events·h–1) was 23.4% in women and 49.7% in men, and the prevalence of symptomatic OSA was 9% and 13%, respectively [2]. However, in some populations, the prevalence of OSA is substantially higher, such as in patients been evaluated for bariatric surgery (estimated range 70–80%), in patients who have had a transient ischaemic attack or stroke (estimated range 60–70%) and in patients with cardiometabolic disease [3–6]. Limited data have been reported on CSA and non-obstructive sleep-related hypoventilation, which have received considerable interest in the sleep field within the past 10 years. Even if their prevalence was noted to be quite low relative to the prevalence of OSA [7], they are quite common in specific subpopulations [8–10].




    ee

    "ERS International Congress 2019: highlights from Best Abstract awardees". Lorna E. Latimer, Marieke Duiverman, Mahmoud I. Abdel-Aziz, Gulser Caliskan, Sara M. Mensink-Bout, Alberto Mendoza-Valderrey, Aurelien Justet, Junichi Omura, Karthi Srika




    ee

    Lung cancer incidence and mortality with extended follow-up in the National Lung Screening Trial

    Since lung cancer (LC) is still the leading cause of cancer deaths worldwide [1], early detection through screening represents an important opportunity to improve LC survival and is a priority area for cancer care. The National Lung Screening Trial (NLST) aimed to compare low-dose helical computed tomography (LDCT) with chest radiography in LC screening of current or former heavy smokers. The trial found a relative reduction in mortality from LC of 20% in those who had undergone LDCT screening. LC screening has regained prominence in the thoracic oncology literature with the completion of NELSON and other European trials, which support the role of LC screening in achieving early diagnosis and reducing mortality. A growing number of implementation pilots are providing an impetus towards organised, national programmes for LC screening, which are in need of long-term follow-up data such as those presented in this study.




    ee

    Lung cancer incidence and mortality with extended follow-up in the National LungScreening Trial

    A 78-year-old male presented at the emergency room complaining of dry cough, fever up to 38.5 °C and malaise for 1 month. He had visited a general practitioner and received amoxicillin 500 mg three times a day for 7 days for a presumed chest infection, without improvement. He had a history of diabetes and arterial blood hypertension, for which he was receiving metformin 1000 mg twice a day and amlodipine 10 mg a day for 7 years. He reported no alcohol abuse and was an ex-smoker of 20 pack-years (quit 30 years ago). He had no recent hospitalisations or any medical interventions.




    ee

    Screening for obstructive sleep apnoea in professional drivers

    Professional drivers show a higher prevalence of obstructive sleep apnoea (OSA) compared with the general population. Furthermore, there is concern about the association between OSA and car crash risk given that drivers with OSA show an increased risk for car accidents. Despite this risk, OSA is often underdiagnosed and undertreated in this population, mainly due to lack of appropriate screening and sleep study referrals. Polysomnography (PSG), the gold standard test, is inappropriate for systematic screening because of its high expense, complexity and relative inaccessibility in this population. Therefore, there is a strong demand for good screening tools, including both subjective and objective data that may assist in early identification of possible OSA among professional drivers and, thus, aid in PSG examination referral and OSA management in an accredited sleep centre. However, there is considerable disagreement over screening methods and criteria for triggering a sleep study referral in different countries. There is also a strong need for further research in the area of OSA screening of commercial drivers in order to improve the diagnostic accuracy of screening tools and ensure that patients with OSA are accurately identified.

    Key points

  • Obstructive sleep apnoea (OSA) is often undiagnosed and undertreated in professional drivers.

  • Professional drivers often under-report and are reluctant to report OSA symptoms.

  • Barriers to OSA diagnosis include appropriate screening and sleep study referrals.

  • Screening tools including both subjective and objective data may assist in early identification of possible OSA among professional drivers.

  • Educational aims

  • To evaluate screening instruments currently used to identify OSA risk in professional drivers.

  • To provide guidance for developing an assessment strategy for OSA by professional driver medical examiners.




    ee

    Sleep Restriction and Memory and Learning in Adolescents




    ee

    The authors respond to "The future of colorectal cancer screening: Parentalism or shared decision-making?" [Letters]




    ee

    The future of colorectal cancer screening: Parentalism or shared decision-making? [Letters]




    ee

    An Individual Participant Data Population Pharmacokinetic Meta-analysis of Drug-Drug Interactions between Lumefantrine and Commonly Used Antiretroviral Treatment [Clinical Therapeutics]

    Treating malaria in HIV-coinfected individuals should consider potential drug-drug interactions. Artemether-lumefantrine is the most widely recommended treatment for uncomplicated malaria globally. Lumefantrine is metabolized by CYP3A4, an enzyme that commonly used antiretrovirals often induce or inhibit. A population pharmacokinetic meta-analysis was conducted using individual participant data from 10 studies with 6,100 lumefantrine concentrations from 793 nonpregnant adult participants (41% HIV-malaria-coinfected, 36% malaria-infected, 20% HIV-infected, and 3% healthy volunteers). Lumefantrine exposure increased 3.4-fold with coadministration of lopinavir-ritonavir-based antiretroviral therapy (ART), while it decreased by 47% with efavirenz-based ART and by 59% in the patients with rifampin-based antituberculosis treatment. Nevirapine- or dolutegravir-based ART and malaria or HIV infection were not associated with significant effects. Monte Carlo simulations showed that those on concomitant efavirenz or rifampin have 49% and 80% probability of day 7 concentrations <200 ng/ml, respectively, a threshold associated with an increased risk of treatment failure. The risk of achieving subtherapeutic concentrations increases with larger body weight. An extended 5-day and 6-day artemether-lumefantrine regimen is predicted to overcome these drug-drug interactions with efavirenz and rifampin, respectively.




    ee

    In Vitro Screening of the Open-Source Medicines for Malaria Venture Malaria and Pathogen Boxes To Discover Novel Compounds with Activity against Balamuthia mandrillaris [Susceptibility]

    Balamuthia mandrillaris is an under-reported, pathogenic free-living amoeba that causes Balamuthia amoebic encephalitis (BAE) and cutaneous skin infections. Although cutaneous infections are not typically lethal, BAE with or without cutaneous involvement is usually fatal. This is due to the lack of drugs that are both efficacious and can cross the blood-brain barrier. We aimed to discover new leads for drug discovery by screening the open-source Medicines for Malaria Venture (MMV) Malaria Box and MMV Pathogen Box, with 800 compounds total. From an initial single point screen at 1 and 10 μM, we identified 54 hits that significantly inhibited the growth of B. mandrillaris in vitro. Hits were reconfirmed in quantitative dose-response assays and 23 compounds (42.6%) were confirmed with activity greater than miltefosine, the current standard of care.




    ee

    Safety and Pharmacokinetic Characterization of Nacubactam, a Novel {beta}-Lactamase Inhibitor, Alone and in Combination with Meropenem, in Healthy Volunteers [Clinical Therapeutics]

    Nacubactam is a novel β-lactamase inhibitor with dual mechanisms of action as an inhibitor of serine β-lactamases (classes A and C and some class D) and an inhibitor of penicillin binding protein 2 in Enterobacteriaceae. The safety, tolerability, and pharmacokinetics of intravenous nacubactam were evaluated in single- and multiple-ascending-dose, placebo-controlled studies. Healthy participants received single ascending doses of nacubactam of 50 to 8,000 mg, multiple ascending doses of nacubactam of 1,000 to 4,000 mg every 8 h (q8h) for up to 7 days, or nacubactam of 2,000 mg plus meropenem of 2,000 mg q8h for 6 days after a 3-day lead-in period. Nacubactam was generally well tolerated, with the most frequently reported adverse events (AEs) being mild to moderate complications associated with intravenous access and headache. There was no apparent relationship between drug dose and the pattern, incidence, or severity of AEs. No clinically relevant dose-related trends were observed in laboratory safety test results. No serious AEs, dose-limiting AEs, or deaths were reported. After single or multiple doses, nacubactam pharmacokinetics appeared linear, and exposure increased in an approximately dose-proportional manner across the dose range investigated. Nacubactam was excreted largely unchanged into urine. Coadministration of nacubactam with meropenem did not significantly alter the pharmacokinetics of either drug. These findings support the continued clinical development of nacubactam and demonstrate the suitability of meropenem as a potential β-lactam partner for nacubactam. (The studies described in this paper have been registered at ClinicalTrials.gov under NCT02134834 [single ascending dose study] and NCT02972255 [multiple ascending dose study].)




    ee

    Comparison of Treatment Outcomes between Analysis Populations in the RESTORE-IMI 1 Phase 3 Trial of Imipenem-Cilastatin-Relebactam versus Colistin plus Imipenem-Cilastatin in Patients with Imipenem-Nonsusceptible Bacterial Infections [Clinical Therapeutic

    The RESTORE-IMI 1 phase 3 trial demonstrated the efficacy and safety of imipenem-cilastatin (IMI) combined with relebactam (REL) for treating imipenem-nonsusceptible infections. The objective of this analysis was to compare the outcomes among patients meeting eligibility requirements based on central laboratory susceptibility versus local laboratory susceptibility. Patients with serious infections caused by imipenem-nonsusceptible, colistin-susceptible, and imipenem-REL-susceptible pathogens were randomized 2:1 to IMI-REL plus placebo or colistin plus IMI for 5 to 21 days. The primary endpoint was a favorable overall response. Key endpoints included the clinical response and all-cause mortality. We compared outcomes between the primary microbiological modified intent-to-treat (mMITT) population, where eligibility was based on central laboratory susceptibility testing, and the supplemental mMITT (SmMITT) population, where eligibility was based on local, site-level testing. The SmMITT (n = 41) and MITT (n = 31) populations had similar baseline characteristics, including sex, age, illness severity, and renal function. In both analysis populations, favorable overall response rates in the IMI-REL treatment group were >70%. Favorable clinical response rates at day 28 were 71.4% for IMI-REL and 40.0% for colistin plus IMI in the mMITT population, whereas they were 75.0% for IMI-REL and 53.8% for colistin plus IMI in the SmMITT population. Day 28 all-cause mortality rates were 9.5% for IMI-REL and 30.0% for colistin plus IMI in the mMITT population, whereas they were 10.7% for IMI-REL and 23.1% for colistin plus IMI in the SmMITT population. The outcomes in the SmMITT population were generally consistent with those in the mMITT population, suggesting that outcomes may be applicable to the real-world use of IMI-REL for treating infections caused by imipenem-nonsusceptible Gram-negative pathogens. (This study has been registered at ClinicalTrials.gov under identifier NCT02452047.)




    ee

    Discordance between Etravirine Phenotype and Genotype-Based Predicted Phenotype for Subtype C HIV-1 from First-Line Antiretroviral Therapy Failures in South Africa [Antiviral Agents]

    Etravirine (ETR) is a nonnucleoside reverse transcriptase inhibitor (NNRTI) used in treatment-experienced individuals. Genotypic resistance test-interpretation systems can predict ETR resistance; however, genotype-based algorithms are derived primarily from HIV-1 subtype B and may not accurately predict resistance in non-B subtypes. The frequency of ETR resistance among recombinant subtype C HIV-1 and the accuracy of genotypic interpretation systems were investigated. HIV-1LAI containing full-length RT from HIV-1 subtype C-positive individuals experiencing virologic failure (>10,000 copies/ml and >1 NNRTI resistance-associated mutation) were phenotyped for ETR susceptibility. Fold change (FC) was calculated against a composite 50% effective concentration (EC50) from treatment-naive individuals and three classifications were assigned: (i) <2.9-FC, susceptible; (ii) ≥2.9- to 10-FC, partially resistant; and (iii) >10-FC, fully resistant. The Stanford HIVdb-v8.4 was used for genotype predictions merging the susceptible/potential low-level and low-level/intermediate groups for 3 x 3 comparison. Fifty-four of a hundred samples had reduced ETR susceptibility (≥2.9-FC). The FC correlated with HIVdb-v8.4 (Spearman’s rho = 0.62; P < 0.0001); however, 44% of samples were partially (1 resistance classification difference) and 4% completely discordant (2 resistance classification differences). Of the 34 samples with an FC of >10, 26 were HIVdb-v8.4 classified as low-intermediate resistant. Mutations L100I, Y181C, or M230L were present in 27/34 (79%) of samples with an FC of >10 but only in 2/46 (4%) of samples with an FC of <2.9. No other mutations were associated with ETR resistance. Viruses containing the mutation K65R were associated with reduced ETR susceptibility, but 65R reversions did not increase ETR susceptibility. Therefore, genotypic interpretation systems were found to misclassify ETR susceptibility in HIV-1 subtype C samples. Modifications to genotypic algorithms are needed to improve the prediction of ETR resistance for the HIV-1 subtype C.




    ee

    Whole-Cell Phenotypic Screening of Medicines for Malaria Venture Pathogen Box Identifies Specific Inhibitors of Plasmodium falciparum Late-Stage Development and Egress [Experimental Therapeutics]

    We report a systematic, cellular phenotype-based antimalarial screening of the Medicines for Malaria Venture Pathogen Box collection, which facilitated the identification of specific blockers of late-stage intraerythrocytic development of Plasmodium falciparum. First, from standard growth inhibition assays, we identified 173 molecules with antimalarial activity (50% effective concentration [EC50] ≤ 10 μM), which included 62 additional molecules over previously known antimalarial candidates from the Pathogen Box. We identified 90 molecules with EC50 of ≤1 μM, which had significant effect on the ring-trophozoite transition, while 9 molecules inhibited the trophozoite-schizont transition and 21 molecules inhibited the schizont-ring transition (with ≥50% parasites failing to proceed to the next stage) at 1 μM. We therefore rescreened all 173 molecules and validated hits in microscopy to prioritize 12 hits as selective blockers of the schizont-ring transition. Seven of these molecules inhibited the calcium ionophore-induced egress of Toxoplasma gondii, a related apicomplexan parasite, suggesting that the inhibitors may be acting via a conserved mechanism which could be further exploited for target identification studies. We demonstrate that two molecules, MMV020670 and MMV026356, identified as schizont inhibitors in our screens, induce the fragmentation of DNA in merozoites, thereby impairing their ability to egress and invade. Further mechanistic studies would facilitate the therapeutic exploitation of these molecules as broadly active inhibitors targeting late-stage development and egress of apicomplexan parasites relevant to human health.




    ee

    Correction: Senescence Sensitivity of Breast Cancer Cells Is Defined by Positive Feedback Loop between CIP2A and E2F1 [Correction]




    ee

    CAR Engineering Comes to Macrophages [News in Brief]

    Human macrophages equipped with chimeric antigen receptor constructs infiltrate solid tumors, ingest malignant tissue, and stimulate adaptive immunity in mouse models. Several new biotech companies are racing to bring the technology into clinical trials.




    ee

    Non-Stem Cells Seed Colorectal Cancer Metastases and Gain Stem Traits [Metastasis]

    LGR5 cells seed colorectal cancer metastases and produce stemlike LGR5+ outgrowth-promoting cells.




    ee

    Total Antioxidant Capacity and Pancreatic Cancer Incidence and Mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

    Background:

    Total antioxidant capacity (TAC) reflects an individual's overall antioxidant intake. We sought to clarify whether higher TAC is associated with lower risks of pancreatic cancer incidence and mortality in the U.S. general population.

    Methods:

    A total of 96,018 American adults were identified from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. A ferric-reducing ability of plasma score was used to reflect an individual's TAC intake from diet and/or supplements. Cox regression was used to calculate hazard ratios (HR) for pancreatic cancer incidence, and competing risk regression was used to calculate subdistribution HRs for pancreatic cancer mortality. Restricted cubic spline regression was used to test nonlinearity.

    Results:

    A total of 393 pancreatic cancer cases and 353 pancreatic cancer–related deaths were documented. Total (diet + supplements) TAC was found to be inversely associated with pancreatic cancer incidence (HR quartile 4 vs. quartile 1 = 0.53; 95% confidence interval, 0.39–0.72; Ptrend = 0.0002) and mortality (subdistribution HR quartile 4 vs. quartile 1 = 0.52; 95% confidence interval 0.38–0.72; Ptrend = 0.0003) in a nonlinear dose–response manner (all Pnonlinearity < 0.01). Similar results were observed for dietary TAC. No association of supplemental TAC with pancreatic cancer incidence and mortality was found.

    Conclusions:

    In the U.S. general population, dietary but not supplemental TAC level is inversely associated with risks of pancreatic cancer incidence and mortality in a nonlinear dose–response pattern.

    Impact:

    This is the first prospective study indicating that a diet rich in antioxidants may be beneficial in decreasing pancreatic cancer incidence and mortality.




    ee

    Accuracy of Self-reported Colonic Polyps: Results from the Prostate, Lung, Colorectal, and Ovarian Screening Trial Study of Colonoscopy Utilization

    Background:

    Colonoscopy follow-up recommendations depend on the presence or absence of polyps, and if found, their number, size, and histology. Patients may be responsible for conveying results between primary and specialty care or providing medical information to family members; thus, accurate reporting is critical. This analysis assessed the accuracy of self-reported colonoscopy findings.

    Methods:

    3,986 participants from the Study of Colonoscopy Utilization, an ancillary study nested within the Prostate, Lung, Colorectal, and Ovarian Screening Trial, were included. Self-reports of polyp and adenoma were compared to medical records, and measures of sensitivity and specificity were calculated. Correlates of accurate self-report of polyp were assessed using logistic regression and weighted to account for study sampling.

    Results:

    The sensitivity and specificity of self-reported polyp findings were 88% and 85%, respectively, and for adenoma 11% and 99%, respectively. Among participants with a polyp, older age was associated with lower likelihood while polyp severity and non-white race were associated with increased likelihood of accurate recall. Among participants without a polyp, having multiple colonoscopies was associated with lower likelihood while family history of colorectal cancer was associated with increased likelihood of accurate recall. Among both groups, longer time since colonoscopy was associated with lower likelihood of accurate recall.

    Conclusions:

    Participants recalled with reasonable accuracy whether they had a prior polyp; however, recall of histology, specifically adenoma, was much less accurate.

    Impact:

    Identification of strategies to increase accurate self-report of colonic polyps are needed, particularly for patient–provider communications and patient reporting of results to family members.




    ee

    Harnessing Population Pedigree Data and Machine Learning Methods to Identify Patterns of Familial Bladder Cancer Risk

    Background:

    Relatives of patients with bladder cancer have been shown to be at increased risk for kidney, lung, thyroid, and cervical cancer after correcting for smoking-related behaviors that may concentrate in some families. We demonstrate a novel approach to simultaneously assess risks for multiple cancers to identify distinct multicancer configurations (multiple different cancer types that cluster in relatives) surrounding patients with familial bladder cancer.

    Methods:

    This study takes advantage of a unique population-level data resource, the Utah Population Database (UPDB), containing vast genealogy and statewide cancer data. Familial risk is measured using standardized incidence risk (SIR) ratios that account for sex, age, birth cohort, and person-years of the pedigree members.

    Results:

    We identify 1,023 families with a significantly higher bladder cancer rate than population controls (familial bladder cancer). Familial SIRs are then calculated across 25 cancer types, and a weighted Gower distance with K-medoids clustering is used to identify familial multicancer configurations (FMC). We found five FMCs, each exhibiting a different pattern of cancer aggregation. Of the 25 cancer types studied, kidney and prostate cancers were most commonly enriched in the familial bladder cancer clusters. Laryngeal, lung, stomach, acute lymphocytic leukemia, Hodgkin disease, soft-tissue carcinoma, esophageal, breast, lung, uterine, thyroid, and melanoma cancers were the other cancer types with increased incidence in familial bladder cancer families.

    Conclusions:

    This study identified five familial bladder cancer FMCs showing unique risk patterns for cancers of other organs, suggesting phenotypic heterogeneity familial bladder cancer.

    Impact:

    FMC configurations could permit better definitions of cancer phenotypes (subtypes or multicancer) for gene discovery and environmental risk factor studies.




    ee

    Screen to Save: Results from NCI's Colorectal Cancer Outreach and Screening Initiative to Promote Awareness and Knowledge of Colorectal Cancer in Racial/Ethnic and Rural Populations

    Background:

    The Center to Reduce Cancer Health Disparities (CRCHD), NCI, implemented Screen to Save, NCI's Colorectal Cancer Outreach and Screening Initiative to promote awareness and knowledge of colorectal cancer in racial/ethnic and rural populations.

    Methods:

    The initiative was implemented through CRCHD's National Outreach Network (NON). NON is a national network of Community Health Educators (CHE), aligned with NCI-designated Cancer Centers across the nation. In phases I and II, the CHEs focused on the dissemination of cancer-related information and implementation of evidence-based educational outreach.

    Results:

    In total, 3,183 pre/post surveys were obtained from male and female participants, ages 50 to 74 years, during the 347 educational events held in phase I. Results demonstrated all racial/ethnic groups had an increase in colorectal cancer–related knowledge, and each group strongly agreed that the educational event increased the likelihood that they would engage in colorectal cancer–related healthful behaviors (e.g., obtain colorectal cancer screening and increase physical activity). For phase II, Connections to Care, event participants were linked to screening. Eighty-two percent of the participants who obtained colorectal cancer screening during the 3-month follow-up period obtained their screening results.

    Conclusions:

    These results suggest that culturally tailored, standardized educational messaging and data collection tools are key change agents that can serve to inform the effectiveness of educational outreach to advance awareness and knowledge of colorectal cancer.

    Impact:

    Future initiatives should focus on large-scale national efforts to elucidate effective models of connections to care, related to colorectal cancer screening, follow-up, and treatments that are modifiable to meet community needs.




    ee

    The Impact of One-week Dietary Supplementation with Kava on Biomarkers of Tobacco Use and Nitrosamine-based Carcinogenesis Risk among Active Smokers

    Tobacco smoking is the primary risk factor for lung cancer, driven by the addictive nature of nicotine and the indisputable carcinogenicity of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) as well as other compounds. The integration of lung cancer chemoprevention with smoking cessation is one potential approach to reduce this risk and mitigate lung cancer mortality. Experimental data from our group suggest that kava, commonly consumed in the South Pacific Islands as a beverage to promote relaxation, may reduce lung cancer risk by enhancing NNK detoxification and reducing NNK-derived DNA damage. Building upon these observations, we conducted a pilot clinical trial to evaluate the effects of a 7-day course of kava on NNK metabolism in active smokers. The primary objective was to compare urinary total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL plus its glucuronides, major metabolites of NNK) before and after kava administration as an indicator of NNK detoxification. Secondary objectives included determining kava's safety, its effects on DNA damage, tobacco use, and cortisol (a biomarker of stress). Kava increased urinary excretion of total NNAL and reduced urinary 3-methyladenine in participants, suggestive of its ability to reduce the carcinogenicity of NNK. Kava also reduced urinary total nicotine equivalents, indicative of its potential to facilitate tobacco cessation. Plasma cortisol and urinary total cortisol equivalents were reduced upon kava use, which may contribute to reductions in tobacco use. These results demonstrate the potential of kava intake to reduce lung cancer risk among smokers.




    ee

    Oral Microbiome Profiling in Smokers with and without Head and Neck Cancer Reveals Variations Between Health and Disease

    While smoking is inextricably linked to oral/head and neck cancer (HNSCC), only a small fraction of smokers develop HNSCC. Thus, we have sought to identify other factors, which may influence the development of HNSCC in smokers including microbiology. To determine microbial associations with HNSCC among tobacco users, we characterized oral microbiome composition in smokers with and without HNSCC. 16S rRNA MiSeq sequencing was used to examine the oral mucosa microbiome of 27 smokers with (cases) and 24 without HNSCC (controls). In addition, we correlated previously reported levels of DNA damage with the microbiome data. Smokers with HNSCC showed lower microbiome richness compared with controls (q = 0.012). Beta-diversity analyses, assessed as UniFrac (weighted and unweighted) and Bray–Curtis distances, showed significant differences in oral mucosal microbiome signatures between cases and controls (r2 = 0.03; P = 0.03) and higher interindividual microbiome heterogeneity in the former (q ≤ 0.01). Higher relative abundance of Stenotrophomonas and Comamonadaceae and predicted bacterial pathways mainly involved in xenobiotic and amine degradation were found in cases compared with controls. The latter, in contrast, exhibited higher abundance of common oral commensals and predicted sugar degradation pathways. Finally, levels of DNA damage in the oral cavity were correlated with the microbiome profiles above. Oral microbiome traits differ in smokers with and without HNSCC, potentially informing the risk of eventual HNSCC and shedding light into possible microbially mediated mechanisms of disease. These findings present data that may be useful in screening efforts for HNSCC among smokers who are unable to quit.




    ee

    Estimating the Screening-Eligible Population Size, Ages 45-74, at Average Risk to Develop Colorectal Cancer in the United States

    Colorectal cancer is a growing burden in adults less than 50 years old. In 2018, the American Cancer Society published a guideline update recommending a reduction in the colorectal cancer screening start age for average-risk individuals from 50 to 45. Implementing these recommendations would have important implications for public health. However, the approximate number of people impacted by this change, the average-risk population ages 45–49, is not well-described in the literature. Here, we provide methodology to conservatively estimate the average-risk and screening-eligible population in the United States, including those who would be impacted by a lowered colorectal cancer screening start age. Using multiple data sources, we estimated the current average-risk population by subtracting individuals with symptomatic colorectal cancer, with a family history of colorectal cancer, and with inflammatory bowel disease and hereditary nonpolyposis colorectal cancer from the total population. Within this population, we estimated the number of screening-eligible individuals by subtracting those with previous colorectal cancer screening (45- to 49-year-old) or up to date with colorectal cancer screening (50- to 74-year-old). The total average-risk population is estimated between 102.1 and 106.5 million people, of whom 43.4–45.2 million people are eligible for colorectal cancer screening. Lowering the screening age would add roughly 19 million people to the average-risk population and increase the current number of screening-eligible individuals on immediate implementation by over 60% (from 27 to 44 million). Estimating the population size impacted by lowering the recommended colorectal cancer screening start age enables more accurate decision-making for policymakers and epidemiologists focused on cancer prevention.




    ee

    You Must Remember Meeting Clara: Remembering Clara Derber Bloomfield (1942-2020)




    ee

    Comparison of Enhancement of the Vestibular Perilymph between Variable and Constant Flip Angle-Delayed 3D-FLAIR Sequences in Meniere Disease [HEAD & NECK]

    BACKGROUND AND PURPOSE:

    Endolymphatic hydrops in patients with Menière disease relies on delayed postcontrast 3D-FLAIR sequences. The purpose of this study was to compare the degree of perilymphatic enhancement and the detection rate of endolymphatic hydrops using constant and variable flip angles sequences.

    MATERIALS AND METHODS:

    This was a retrospective study performed in 16 patients with Menière disease who underwent 3T MR imaging 4 hours after gadolinium injection using two 3D-FLAIR sequences with a constant flip angle at 140° for the first and a heavily-T2 variable flip angle for the second. The signal intensity ratio was measured using the ROI method. We graded endolymphatic hydrops and evaluated the cochlear blood-labyrinth barrier impairment.

    RESULTS:

    Both for symptomatic and asymptomatic ears, the median signal intensity ratio was significantly higher with the constant flip angle than with the heavily-T2 variable flip angle (7.16 versus 1.54 and 7.00 versus 1.45, P < .001). Cochlear blood-labyrinth barrier impairment was observed in 4/18 symptomatic ears with the heavily-T2 variable flip angle versus 8/19 with constant flip angle sequences. With heavily-T2 variable flip angle sequences, endolymphatic hydrops was observed in 7–10/19 symptomatic ears versus 12/19 ears with constant flip angle sequences. We found a significant association between the clinical symptomatology and the presence of endolymphatic hydrops with constant flip angle but not with heavily-T2 variable flip angle sequences. Interreader agreement was always perfect with constant flip angle sequences while it was fair-to-moderate with heavily-T2 variable flip angle sequences.

    CONCLUSIONS:

    3D-FLAIR constant flip angle sequences provide a higher signal intensity ratio and are superior to heavily-T2 variable flip angle sequences in reliably evaluating the cochlear blood-labyrinth barrier impairment and the endolymphatic space.




    ee

    Discrimination between Glioblastoma and Solitary Brain Metastasis: Comparison of Inflow-Based Vascular-Space-Occupancy and Dynamic Susceptibility Contrast MR Imaging [FUNCTIONAL]

    BACKGROUND AND PURPOSE:

    Accurate differentiation between glioblastoma and solitary brain metastasis is of vital importance clinically. This study aimed to investigate the potential value of the inflow-based vascular-space-occupancy MR imaging technique, which has no need for an exogenous contrast agent, in differentiating glioblastoma and solitary brain metastasis and to compare it with DSC MR imaging.

    MATERIALS AND METHODS:

    Twenty patients with glioblastoma and 22 patients with solitary brain metastasis underwent inflow-based vascular-space-occupancy and DSC MR imaging with a 3T clinical scanner. Two neuroradiologists independently measured the maximum inflow-based vascular-space-occupancy–derived arteriolar CBV and DSC-derived CBV values in intratumoral regions and peritumoral T2-hyperintense regions, which were normalized to the contralateral white matter (relative arteriolar CBV and relative CBV, inflow-based vascular-space-occupancy relative arteriolar CBV, and DSC-relative CBV). The intraclass correlation coefficient, Student t test, or Mann-Whitney U test and receiver operating characteristic analysis were performed.

    RESULTS:

    All parameters of both regions had good or excellent interobserver reliability (0.74~0.89). In peritumoral T2-hyperintese regions, DSC-relative CBV (P < .001), inflow-based vascular-space-occupancy arteriolar CBV (P = .001), and relative arteriolar CBV (P = .005) were significantly higher in glioblastoma than in solitary brain metastasis, with areas under the curve of 0.94, 0.83, and 0.72 for discrimination, respectively. In the intratumoral region, both inflow-based vascular-space-occupancy arteriolar CBV and relative arteriolar CBV were significantly higher in glioblastoma than in solitary brain metastasis (both P < .001), with areas under the curve of 0.91 and 0.90, respectively. Intratumoral DSC-relative CBV showed no significant difference (P = .616) between the 2 groups.

    CONCLUSIONS:

    Inflow-based vascular-space-occupancy has the potential to discriminate glioblastoma from solitary brain metastasis, especially in the intratumoral region.




    ee

    Novel Coronavirus: What Neuroradiologists as Citizens of the World Need to Know [EDITORIALS]




    ee

    Time to Refine How We Tweet? [LETTERS]




    ee

    Shophouse Green River quận 8, chung cư nằm trên mặt tiền Phạm Thế Hiển, phục vụ hơn 4000 cư dân

    * Chỉ còn 12 ngày cơ hội cho khách hàng chọn mua siêu phẩm shophouse Green River 4 mặt tiền tại Phạm Thế Hiển - Quận 8. Quý KH nào chưa mua hoặc đang phân vân về dự án hãy chọn cho mình 1 căn trong siêu dự án tiềm năng tăng giá cực kì cao này nhé. - Liên hệ trưởng phòng kinh doan...