Neurotensin Receptor 1 Is Expressed in Gastrointestinal Stromal Tumors but Not in Interstitial Cells of Cajal

Gastrointestinal stromal tumors (GIST) are thought to derive from the interstitial cells of Cajal (ICC) or an ICC precursor. Oncogenic mutations of the KIT or PDGFRA receptor tyrosine kinases are present in the majority of GIST, leading to ligand-independent activation of the intracellular signal transduction pathways. We previously investigated the gene expression profile in the murine KitK641E GIST model and identified Ntsr1 mRNA, encoding the Neurotensin receptor 1, amongst the upregulated genes. Here we characterized Ntsr1 mRNA and protein expression in the murine KitK641E GIST model and in tissue microarrays of human GIST. Ntsr1 mRNA upregulation in KitK641E animals was confirmed by quantitative PCR. Ntsr1 immunoreactivity was not detected in the Kit positive ICC of WT mice, but was present in the Kit positive hyperplasia of KitK641E mice. In the normal human gut, NTSR1 immunoreactivity was detected in myenteric neurons but not in KIT positive ICC. Two independent tissue microarrays, including a total of 97 GIST, revealed NTSR1 immunoreactivity in all specimens, including the KIT negative GIST with PDGFRA mutation. NTSR1 immunoreactivity exhibited nuclear, cytoplasmic or mixed patterns, which might relate to variable levels of NTSR1 activation. As studies using radio-labeled NTSR1 ligand analogues for whole body tumor imaging and for targeted therapeutic interventions have already been reported, this study opens new perspectives for similar approaches in GIST

A Model for Interprofessional Health Disparities Education: Student-Led Curriculum on Chronic Hepatitis B Infection

Although health disparities are commonly addressed in preclinical didactic curricula, direct patient care activities with affected communities are more limited. To address this problem, health professional students designed a preclinical service-learning curriculum on hepatitis B viral (HBV) infection, a major health disparity affecting the Asian/Pacific Islander (API) population, integrating lectures, skills training, and direct patient care at student-run clinics. An urban health professions campus. Medical and other health professional students at University of California, San Francisco, organized a preclinical didactic and experiential elective, and established two monthly clinics offering HBV screening, vaccination, and education to the community. Between 2004 and 2009, 477 students enrolled in the student-led HBV curriculum. Since the clinics’ inception in 2007, 804 patients have been screened for chronic HBV; 87% were API immigrants, 63% had limited English proficiency, and 46% were uninsured. Serologically, 10% were found to be chronic HBV carriers, 44% were susceptible to HBV, and 46% were immune. Our student-led didactic and experiential elective can serve as an interprofessional curricular model for learning about specific health disparities while providing important services to the local community

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Incidence, prevalence, and risk factors of infectious uveitis and scleritis in the United States: A claims-based analysis.

BackgroundOcular inflammation causes significant visual morbidity in the United States, yet little is known about the epidemiology of infectious uveitis and scleritis. This study aims to evaluate the epidemiology of infectious uveitis/scleritis employing a large national medical claims database.MethodsThis was a retrospective, case-control study, employing Optum's de-identified Clinformatics® Data Mart Database, containing data from 21.5 million privately insured individuals with enrollment for at least 15 months within 2007-2015. Inclusion in the uveitis/scleritis sample required an index uveitis/scleritis diagnosis based on International Classification of Diseases, Ninth Revision (ICD-9) codes. Exclusion criteria included index date within 3 months after intraocular surgery. Rates for uveitis/scleritis were determined by anatomic site. Multivariable logistic regression analyses were performed to determine odds ratios for the incidence and prevalence of uveitis/scleritis by anatomic category.FindingsInfectious etiologies accounted for less than 20% of uveitis/scleritis, with mean rates of 18.9 (incidence) and 60.6 (prevalence) per 100,000 persons. The mean prevalences of infectious anterior, intermediate, posterior, panuveitis, and scleritis were 27.7, 0.17, 23.4, 4.4, and 4.6, per 100,000, respectively. Overall risk of prevalent infectious uveitis/scleritis increased with age (OR>3.3 for each decade over age 18, pConclusionsThe incidence and prevalence of infectious uveitis/scleritis in the United States were higher than previously reported estimates but remained lower than in developing countries. Rates varied by age, sex, race, and medical comorbidities, and may reflect differential susceptibility to various infectious agents with disparate geographic distributions within the United States

Drusen Regression is Associated With Local Changes in Fundus Autofluorescence in Intermediate Age-Related Macular Degeneration

PurposeTo investigate the association of spontaneous drusen regression in intermediate age-related macular degeneration (AMD) with changes on fundus photography and fundus autofluorescence (FAF) imaging.DesignProspective observational case series.MethodsFundus images from 58 eyes (in 58 patients) with intermediate AMD and large drusen were assessed over 2 years for areas of drusen regression that exceeded the area of circle C1 (diameter 125 μm; Age-Related Eye Disease Study grading protocol). Manual segmentation and computer-based image analysis were used to detect and delineate areas of drusen regression. Delineated regions were graded as to their appearance on fundus photographs and FAF images, and changes in FAF signal were graded manually and quantitated using automated image analysis.ResultsDrusen regression was detected in approximately half of study eyes using manual (48%) and computer-assisted (50%) techniques. At year-2, the clinical appearance of areas of drusen regression on fundus photography was mostly unremarkable, with a majority of eyes (71%) demonstrating no detectable clinical abnormalities, and the remainder (29%) showing minor pigmentary changes. However, drusen regression areas were associated with local changes in FAF that were significantly more prominent than changes on fundus photography. A majority of eyes (64%-66%) demonstrated a predominant decrease in overall FAF signal, while 14%-21% of eyes demonstrated a predominant increase in overall FAF signal.ConclusionsFAF imaging demonstrated that drusen regression in intermediate AMD was often accompanied by changes in local autofluorescence signal. Drusen regression may be associated with concurrent structural and physiologic changes in the outer retina

Assessment of HBV Preventive Services in a Medically Underserved Asian and Pacific Islander Population Using Provider and Patient Data

BackgroundHepatitis B (HBV) represents a significant health disparity among medically underserved Asian and Hawaiian/Pacific Islander (API) populations. Studies evaluating adherence to HBV screening and vaccination guidelines in this population are limited.ObjectiveThe purpose of this study was to evaluate HBV screening and vaccination practices using both provider self-report and patient records.DesignMedical records for 20,574 API adults were reviewed retrospectively and primary care providers were surveyed to evaluate rates and adherence to HBV screening and vaccination guidelines.ParticipantsThe study included primary care providers and their adult API patients in the San Francisco safety-net healthcare system.Main measuresPatient, practice, and provider factors, as well as HBV screening and vaccination practices, were assessed using provider survey constructs and patient laboratory and clinical data. Generalized linear mixed models and multivariate logistic regression analyses were used to identify factors associated with recommended HBV screening and vaccination.Key resultsThe mean age of patients was 52 years, and 63.4 % of patients were female. Only 61.5 % underwent HBV testing, and 47.4 % of HBV-susceptible patients were vaccinated. Of 148 (44.8 %) responding providers, most were knowledgeable and had a favorable attitude towards screening, but 43.2 % were unfamiliar with HBV guidelines. HBV screening was positively associated with favorable provider attitude score (OR per unit 1.80, 95 % CI 1.18-2.74) and negatively associated with female patient sex (OR 0.82, 95 % CI 0.73-0.92), a higher number of clinic patients per week (OR per 20 patients 0.46, 95 % CI 0.28-0.76), and provider barrier score (OR per unit 0.45, 95 % CI 0.24-0.87). HBV vaccination was negatively associated with provider barrier score (OR per unit 0.48, 95 % CI 0.25-0.91).ConclusionsRates of HBV screening and vaccination of API patients in this safety-net system are suboptimal, and provider factors play a significant role. Efforts to cultivate positive attitudes among providers and expand healthcare system resources to reduce provider barriers to HBV care are warranted

Variations in Electronic Health Record-Based Definitions of Diabetic Retinopathy Cohorts A Literature Review and Quantitative Analysis

PurposeUse of the electronic health record (EHR) has motivated the need for data standardization. A gap in knowledge exists regarding variations in existing terminologies for defining diabetic retinopathy (DR) cohorts. This study aimed to review the literature and analyze variations regarding codified definitions of DR.DesignLiterature review and quantitative analysis.SubjectsPublished manuscripts.MethodsFour graders reviewed PubMed and Google Scholar for peer-reviewed studies. Studies were included if they used codified definitions of DR (e.g., billing codes). Data elements such as author names, publication year, purpose, data set type, and DR definitions were manually extracted. Each study was reviewed by ≥ 2 authors to validate inclusion eligibility. Quantitative analyses of the codified definitions were then performed to characterize the variation between DR cohort definitions.Main outcome measuresNumber of studies included and numeric counts of billing codes used to define codified cohorts.ResultsIn total, 43 studies met the inclusion criteria. Half of the included studies used datasets based on structured EHR data (i.e., data registries, institutional EHR review), and half used claims data. All but 1 of the studies used billing codes such as the International Classification of Diseases 9th or 10th edition (ICD-9 or ICD-10), either alone or in addition to another terminology for defining disease. Of the 27 included studies that used ICD-9 and the 20 studies that used ICD-10 codes, the most common codes used pertained to the full spectrum of DR severity. Diabetic retinopathy complications (e.g., vitreous hemorrhage) were also used to define some DR cohorts.ConclusionsSubstantial variations exist among codified definitions for DR cohorts within retrospective studies. Variable definitions may limit generalizability and reproducibility of retrospective studies. More work is needed to standardize disease cohorts.Financial disclosuresProprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article