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PubMed2002

Oligoclonal and polyclonal CD4 and CD8 lymphocytes in aplastic anemia and paroxysmal nocturnal hemoglobinuria measured by V beta CDR3 spectratyping and flow cytometry.

We have hypothesized that in aplastic anemia (AA) the presence of antigen-specific T cells is reflected by their contribution to the expansion of a particular variable beta chain (V beta) subfamily and also by clonal CDR3 skewing. To determine the role of disease-specific "signature" T-cell clones in AA, we studied preferential V beta usage by flow cytometry and analyzed V beta-CDR3 regions for the presence of oligoclonality. We first established the contribution of each V beta family to the total CD4(+) and CD8(+) lymphocyte pool; in AA and paroxysmal nocturnal hemoglobinuria, a seemingly random overrepresentation of different V beta families was observed. On average, we found expansion in 3 (of 22 examined) V beta families per patient. When the contribution of individual V beta families to the effector pool was examined, more striking V beta skewing was found. V beta-CDR3 size distribution was analyzed for the expanded V beta families in isolated CD4(+) and CD8(+) populations; underrepresented V beta families displayed more pronounced CDR3 skewing. Expanded CD4(+)V beta subfamilies showed mostly a polyclonal CDR3 size distribution with only 38% of skewing in expanded V beta families. In contrast, within overrepresented CD8(+)V beta types, marked CDR3 skewing (82%) was seen, consistent with nonrandom expansion of specific CD8(+) T-cell clones. No preferential expansion of particular V beta families was observed, in relation to HLA-type. In patients examined after immunosuppressive therapy, an abnormal V beta-distribution pattern was retained, but the degree of expansion of individual V beta was lower. As V beta skewing may correlate with relative V beta size, oligoclonality in combination with numerical V beta expansion can be applied to recognition of disease-specific T-cell receptors.

Anemia, Aplastic↗
PubMed1991

Social validity assessments: is current practice state of the art?

The use of evaluative feedback from consumers to guide program planning and evaluation is often referred to as the assessment of social validity. Differing views of its role and value in applied behavior analysis have emerged, and increasingly stereotyped assessments of social validity are becoming commonplace. This paper argues that current applications of social validity assessments are straying from the point originally proposed for them. Thus, several suggestions for improving current social validity assessment are proposed, including (a) expanding the definition of consumers to acknowledge the variety of community members able and likely to affect a program's survival, (b) increasing the psychometric rigor of social validity assessments, (c) extending assessment to heretofore underrepresented populations, (d) implementing widespread application of well-designed social validity assessments, (e) increasing meaningful consumer involvement in the planning and evaluation of behavioral programs, and (f) educating consumers to make better informed programming decisions.

Community Participation↗
PubMed2026

First report of MUTYH-associated polyposis with c.1353_1355del and c.452A>G mutations in Tolima Grande region from Colombia: a case report.

INTRODUCTION: The MUTYH gene encodes a protein involved in DNA repair and is known for MUTYH-associated polyposis (MAP), a rare autosomal recessive condition that predisposes individuals to colorectal cancer (CRC), colorectal polyps and familial colorectal cancer syndrome. CASE REPORT: We describe the first Tolima Grande region from a Colombian report of individuals carrying pathogenic MUTYH variants c.452A>G and c.1353_1355del associated with polyposis phenotypes. Three main cases with detailed histopathological findings and family history are presented. Additionally, independent findings from Clinaltec identified three further individuals carrying c.452A>G and one heterozygous carrier of c.1353_1355del detected during predictive multigene panel testing. DISCUSSION: These cases highlight the diagnostic and clinical challenges of distinguishing biallelic pathogenic MUTYH variants, which define MAP and confer high CRC risk, from monoallelic carriers, whose cancer risk is substantially lower. Misclassification may result in inappropriate surveillance strategies and missed opportunities for early detection. From a public health perspective, these findings emphasize persistent gaps in hereditary CRC prevention in underrepresented populations, including fragmented cancer registries and limited incorporation of genetic and family history data into clinical decision-making. CONCLUSION: This report provides evidence in Colombia of polyposis-associated pathogenic MUTYH variants c.452A>G and c.1353_1355del, underscoring the importance of expanding genetic evaluation for hereditary CRC in Latin American populations.

Colombian population↗
PubMed2000

[Significance of the BRING-UP studies].

BRING-UP, as already known, is an observational study of outcome of the use of beta-blocker therapy for heart failure. This has been an extraordinary event in clinical medicine: a class of drugs, the beta-blockers, which clinical evidence transformed from being considered as contraindicated into being recommended. This exceptional situation, together with the growing awareness of the limited spread and applicability of evidence produced by trials into clinical practice led to undertaking observational studies to evaluate the feasibility, safety and practical results of the implementation of new therapies recommended for widespread use on the basis of results of controlled, randomized clinical trials. BRING-UP 1 will be followed by BRING-UP 2, the aim of this latter being to assess the effects of beta-blocker therapy on populations underrepresented in randomized trials, and SET-UP, on the use of GP IIb/IIIa platelet receptor inhibitors in unstable angina. BRING-UP has started a new line of research which does not substitute randomized trials, but complements and completes them. For this type of study to become common practice in clinical research, there must be greater interaction and acceptance by pharmaceutical companies and national and international regulatory bodies and a widespread conviction among doctors that this research has a paramount scientific, clinical and social value.

Adrenergic beta-Antagonists↗
PubMed2026

Clinically Relevant Pharmacogenomic Variant Frequencies in Kazakh, Russian, and Uzbek Population Groups Residing in Kazakhstan.

Central Asian populations remain underrepresented in pharmacogenomic research, limiting the availability of population-specific data for genotype-informed prescribing and precision medicine. This study analyzed clinically relevant pharmacogenomic variant frequencies in Kazakh, Russian, and Uzbek population groups residing in Kazakhstan using genome-wide genotype data from 1301 individuals: Kazakh (n = 1111), Russian (n = 156), and Uzbek (n = 34). ClinPGx, a PharmGKB-based clinical annotation framework that prioritizes variant-drug associations according to levels of evidence, was used to select variants with evidence levels 1A, 1B, and 2A. In total, 112 directly genotyped variants were retained for population-specific allele and genotype frequency analysis. All 112 variants were queried against the gnomAD v4.1 genome and exome reference datasets. Of these, matching allele-frequency data for the predefined reported allele were available in at least one of the two gnomAD datasets for 103 variants, whereas for 9 variants the VEP-based query did not return a matching gnomAD frequency for that allele. Frequencies were reported for the same predefined reported allele across all groups, and differences between the study groups were assessed using 95% confidence intervals, Fisher's exact tests, and false discovery rate correction. Genotype counts and the proportions of individuals carrying at least one copy of the reported allele were also summarized for all selected variants. Several pharmacogenomic variants showed population-specific frequency patterns, including NUDT15 rs116855232, SLCO1B1 rs4149056, VKORC1 rs9934438, and UGT1A1 rs10929302. Comparison with gnomAD showed that the observed frequencies were variant-specific and could not be consistently approximated by a single broad genetic ancestry group. Reference-based population structure analysis provided additional ancestry context and supported separate reporting by population group. The study did not evaluate clinical outcomes or make individual prescribing recommendations, and the small Uzbek sample size limits the precision of frequency estimates for this group, particularly for rare variants. Overall, this study provides a clinically prioritized pharmacogenomic frequency resource for underrepresented population groups in Kazakhstan and supports broader Central Asian representation in pharmacogenomic implementation research.

Central Asia↗
PubMed2006

Exclusion and inclusion of nonwhite ethnic minority groups in 72 North American and European cardiovascular cohort studies.

BACKGROUND: Cohort studies are recommended for understanding ethnic disparities in cardiovascular disease. Our objective was to review the process for identifying, including, and excluding ethnic minority populations in published cardiovascular cohort studies in Europe and North America. METHODS AND FINDINGS: We found the literature using Medline (1966-2005), Embase (1980-2001), Cinahl, Web of Science, and citations from references; consultations with colleagues; Internet searches; and RB's personal files. A total of 72 studies were included, 39 starting after 1975. Decision-making on inclusion and exclusion of racial/ethnic groups, the conceptual basis of race/ethnicity, and methods of classification of racial/ethnic groups were rarely explicit. Few publications provided details on the racial/ethnic composition of the study setting or sample, and 39 gave no description. Several studies were located in small towns or in occupational settings, where ethnic minority populations are underrepresented. Studies on general populations usually had too few participants for analysis by race/ethnicity. Eight studies were explicitly on Caucasians/whites, and two excluded ethnic minority groups from the whole or part of the study on the basis of language or birthplace criteria. Ten studies were designed to compare white and nonwhite populations, while five studies focused on one nonwhite racial/ethnic group; all 15 of these were performed in the US. CONCLUSIONS: There is a shortage of information from cardiovascular cohort studies on racial/ethnic minority populations, although this has recently changed in the US. There is, particularly in Europe, an inequity resulting from a lack of research data in nonwhite populations. Urgent action is now required in Europe to address this disparity.

Cardiovascular Diseases↗
PubMed1998

Genetic relationship of populations in China.

Despite the fact that the continuity of morphology of fossil specimens of modern humans found in China has repeatedly challenged the Out-of-Africa hypothesis, Chinese populations are underrepresented in genetic studies. Genetic profiles of 28 populations sampled in China supported the distinction between southern and northern populations, while the latter are biphyletic. Linguistic boundaries are often transgressed across language families studied, reflecting substantial gene flow between populations. Nevertheless, genetic evidence does not support an independent origin of Homo sapiens in China. The phylogeny also suggested that it is more likely that ancestors of the populations currently residing in East Asia entered from Southeast Asia.

Animals↗
PubMed2004

Survey of predators and sampling method comparison in sweet corn.

Natural predation is an important component of integrated pest management that is often overlooked because it is difficult to quantify and perceived to be unreliable. To begin incorporating natural predation into sweet corn, Zea mays L., pest management, a predator survey was conducted and then three sampling methods were compared for their ability to accurately monitor the most abundant predators. A predator survey on sweet corn foliage in New York between 1999 and 2001 identified 13 species. Orius insidiosus (Say), Coleomegilla maculata (De Geer), and Harmonia axyridis (Pallas) were the most numerous predators in all years. To determine the best method for sampling adult and immature stages of these predators, comparisons were made among nondestructive field counts, destructive counts, and yellow sticky cards. Field counts were correlated with destructive counts for all populations, but field counts of small insects were biased. Sticky cards underrepresented immature populations. Yellow sticky cards were more attractive to C. maculata adults than H. axyridis adults, especially before pollen shed, making coccinellid population estimates based on sticky cards unreliable. Field counts were the most precise method for monitoring adult and immature stages of the three major predators. Future research on predicting predation of pests in sweet corn should be based on field counts of predators because these counts are accurate, have no associated supply costs, and can be made quickly.

Animals↗
PubMed2026

Genetic Research on Cardiac Channelopathies in African and African-Descent Populations: A Scoping Review.

Cardiac channelopathies are inherited arrhythmias that can lead to sudden cardiac death. Despite Africa's extensive genomic diversity, African and African-descent populations remain underrepresented in genetic research, creating gaps in variant interpretation and clinical care. This scoping review aims to map the extent, range, and nature of genetic research on cardiac channelopathies in these populations and to identify key geographic, thematic, and methodological gaps. Using the Joanna Briggs Institute scoping review methodology and the Population-Concept-Context framework, systematic searches in PubMed, Embase, and Web of Science identified original human studies on cardiac channelopathies with genetic data. Extracted variables included study characteristics, populations, types of channelopathies, and reported genes and variants. Forty-four studies met the inclusion criteria. Most studies originated from the United States and South Africa, while West, Central, and East Africa were largely underrepresented. US Black individuals and South African individuals of continental African or African-descended ancestry (excluding populations of European descent such as Cape Afrikaner people) were the most studied groups, with other continental African groups rarely included. Long QT syndrome was the predominant focus, and SCN5A, KCNQ1, and KCNH2 were the most frequently analyzed genes. Many of the genetic variants discussed remained of uncertain significance due to limited functional validation and the underrepresentation of African genomes in reference databases. Genetic research on cardiac channelopathies in populations of African ancestry is limited, restricting variant interpretation, counseling, and risk prediction. Broader African inclusion, expanded gene screening, and functional studies are essential to improve diagnostics and promote equity in genomic medicine.

Humans↗
PubMed2002

Increasing incidence of nontyphi Salmonella bacteremia among children living in southern Israel.

OBJECTIVES: To determine if the epidemiology of Salmonella gastroenteritis and childhood bacteremia among the two ethnic populations (Jews and Bedouins) living in southern Israel has changed in recent years. METHODS: Retrospective review of laboratory records and medical charts of patients from whom non-typhi salmonellae were isolated from stool and blood cultures in the 1990-1995 period. RESULTS: The overall incidence of enteric Salmonella infections was 123.5 per 100 000 inhabitants and remained stable during the study period. The incidence of bacteremia among children younger than 4 years increased from 9.3 per 100 000 in the 1990-1992 period to 26.8 per 100 000 in the 1993-1995 period (P 0.01). This increment was especially caused by Salmonella virchow and S. enteritidis, which were also isolated with increasing frequency from stool cultures. The Bedouin population was underrepresented among stool isolates, whereas its representation among blood isolates closely resembled the fraction of this ethnic group in the overall population of the area. CONCLUSIONS: The incidence of enteric salmonellosis has remained stable at a high endemic level in recent years in southern Israel. The incidence of children's bacteremia has experienced a significant increase, associated with S. virchow and S. enteritidis. Differences in the utilization of medical services may explain differences in the epidemiology of Salmonella infections found in the two resident ethnic groups.

Adolescent↗
PubMed1998

NHLBI workshop on the utilization of ECG databases: preservation and use of existing ECG databases and development of future resources.

Baseline examinations and periodic reexaminations in longitudinal population studies, together with ongoing surveillance for morbidity and mortality, provide unique opportunities for seeking ways to enhance the value of the electrocardiogram (ECG) recorded with digital technology as an inexpensive and noninvasive tool for prognosis and diagnosis. Clinicians, epidemiologists, and engineers from industry, government, and academic medical centers gathered at a workshop sponsored by the National Heart, Lung, and Blood Institute (NHLBI) on June 11-12, 1997, to discuss the research potential of ECG databases, their preservation and accession, and standards for recording and storage. Databases considered were those acquired in ongoing and future NHLBI-funded studies and in clinical settings in which the ECG continues to provide valuable information for evaluation and treatment. The accessibility of existing databases, the quality of their data, and the availability of ancillary demographic and clinical information were major themes. Also discussed were appropriate statistical methodologies to be used with these data for developing and testing ECG algorithms. The workshop participants affirmed the value of these databases and urged the establishment of an ECG advisory and review group to (1) resolve technical and proprietary issues for the utilization of currently existing databases; (2) develop standards for recording, storage, and utilization of ECGs in future NHLBI-supported studies; (3) oversee the creation of a national ECG database resource, consisting of an archive of ECG databases from past and ongoing NHLBI-supported studies, and a registry of ECG databases that would eventually include digital ECGs from populations currently underrepresented in the demographic spectrum of the NHLBI databases.

Adolescent↗
PubMed2005

Identifying host sources of fecal pollution: diversity of Escherichia coli in confined dairy and swine production systems.

Repetitive extragenic palindromic PCR fingerprinting of Escherichia coli is one microbial source tracking approach for identifying the host source origin of fecal pollution in aquatic systems. The construction of robust known-source libraries is expensive and requires an informed sampling strategy. In many types of farming systems, waste is stored for several months before being released into the environment. In this study we analyzed, by means of repetitive extragenic palindromic PCR using the enterobacterial repetitive intergenic consensus primers and comparative analysis using the Bionumerics software, collections of E. coli obtained from a dairy farm and from a swine farm, both of which stored their waste as a slurry in holding tanks. In all fecal samples, obtained from either barns or holding tanks, the diversity of the E. coli populations was underrepresented by collections of 500 isolates. In both the dairy and the swine farms, the diversity of the E. coli community was greater in the manure holding tank than in the barn, when they were sampled on the same date. In both farms, a comparison of stored manure samples collected several months apart suggested that the community composition changed substantially in terms of the detected number, absolute identity, and relative abundance of genotypes. Comparison of E. coli populations obtained from 10 different locations in either holding tank suggested that spatial variability in the E. coli community should be accounted for when sampling. Overall, the diversity in E. coli populations in manure slurry storage facilities is significant and likely is problematic with respect to library construction for microbial source tracking applications.

Animal Husbandry↗
PubMed1999

Relationship between primary care practices in medical school admission and the matriculation of underrepresented-minority and female applicants.

PURPOSE: To determine whether primary care-oriented (generalist) admission practices at U.S. medical schools address physician workforce diversity issues by resulting in the admission of more members of underrepresented-minority populations or more women. METHOD: The authors performed cross-sectional, secondary analyses of databases from the Association of American Medical Colleges (AAMC). The independent variables were four generalist admission practices: generalist admission committee chair, greater representation of generalists on admission committee, offering preferential admission to likely generalists, and having a premedical recruitment activity targeting likely generalists. The control variable was public/private school ownership. The dependent variables were the mean ages of the matriculating classes and the proportions of students at each school who were African American, (total) underrepresented minorities, women, and married. RESULTS: Ninety-five percent of medical schools completed the AAMC's Survey of Generalist Physician Initiatives in either 1993 and 1994; 94% of matriculants replied to the AAMC's 1994 Matriculating Student Questionnaire. In multivariable analyses, no admission practice was associated with percentages of African Americans, total underrepresented minorities, or women. CONCLUSIONS: Schools with primary care-oriented admission practices did not admit greater percentages of underrepresented-minority students or women. Additional efforts may be required to attract and admit minority and female applicants.

Black or African American↗
PubMedDate not supplied

Clinical trial resources on the internet must be designed to reach underrepresented minorities.

PURPOSE: Internet-based clinical trial information services are being developed to increase recruitment to studies. However, there are limited data that evaluate their ability to reach elderly and underrepresented minority populations. This study was designed to evaluate the ability of an established clinical trials registry to reach these populations based on expected Internet use. PATIENTS AND METHODS: This study compares general Internet users to participants who enrolled in an Internet based colorectal cancer clinical trials registry established by OncoLink (www.oncolink.org) and the National Colorectal Cancer Research Alliance. Observed rates of demographic groupings were compared to those established for general Internet users. RESULTS: Two thousand, four hundred and thirty-seven participants from the continental United States used the Internet to register for the database. New England, the Mid-Atlantic region, and the Southeast had the highest relative frequency of participation in the database, whereas the Upper Midwest, California, and the South had the lowest rates. Compared to general Internet users, there was an overrepresentation of women (73% vs. 50%) and participants over 55 years old (27% vs. 14%). However, there was an underrepresentation of minorities (10.3% vs. 22%), particularly African Americans (3.1% vs. 8%) and Hispanics (2.8% vs. 9%). DISCUSSION: The Internet is a growing medium for registry into clinical trials databases. However, even taking into account the selection bias of Internet accessibility, there are still widely disparate demographics between general Internet users and those registering for clinical trials, particularly the underrepresentation of minorities. Internet-based educational and recruitment services for clinical trials must be designed to reach these underrepresented minorities to avoid selection biases in future clinical trials.

Black or African American↗
PubMed2004

From trepidant abasia to motor network failure--gait disorders as a consequence of subcortical vascular encephalopathy (SVE): review of historical and contemporary concepts.

Gait disorders in progressive subcortical vascular encephalopathy (SVE) and their impact on the burden of disability in the growing elderly population are underrepresented in medical scientific literature. The absence of a clear framework for the diagnosis and classification for gait disorders on the basis of SVE has multiple reasons: (1) neither movement disorder specialists nor stroke specialists are truly familiar with this topic and feel responsible for its treatment, (2) the existing terminology lacks a clear concept and a consistent classification, and (3) only in recent years have large prospective trials started to address the natural course of SVE. This article reviews the classical descriptions of gait disturbances with preferential view to our present concept of SVE, and comments on historical and current nosology of gait disorders aiming to propose for a new classification.

Basal Ganglia Diseases↗
PubMed2006

Exclusion of elderly persons from health-risk behavior clinical trials.

BACKGROUND: It has been found that the elderly population is underrepresented in clinical trials aimed at disease treatment. It is unknown to what extent this group is also excluded from clinical trials aimed at reducing health-risk behaviors. METHOD: We systematically reviewed clinical trials targeting the leading health-risk behaviors, as identified by Healthy People 2010: tobacco use, overweight/obesity, physical inactivity, substance abuse, and irresponsible sexual behavior. Using MEDLINE, we identified clinical trials published in the five most cited medical journals between January 1990 and May 2004. RESULTS: The majority (53%) of the 198 health-risk behavior clinical trials excluded persons over the age of 65; the exclusion percentage increased to 72% for those over the age of 75. The exclusion of elderly persons in these five medical journals did not decline over the 14 years studied. This age exclusion pattern was not explained by the intervention's intrusiveness or whether illness was an exclusion criterion. The trials that included those over the age of 65 were more likely to report a significant finding in the predicted direction. CONCLUSIONS: Although elderly persons are most at risk for diseases linked to lifestyle behavior, such as heart disease, they were excluded from the majority of health-risk behavior clinical trials in five major medical journals.

Aged↗
PubMed2003

Distinct immune profiles characterize patients with diffuse or limited systemic sclerosis.

Mitogen-stimulated IL-2, IFN-gamma, TNF-alpha (type 1 cytokines), and IL-10 (type 2 cytokine) production by peripheral blood mononuclear cells, as well as expression of surface markers on immune cells, was evaluated in systemic sclerosis (SSc) patients. Fifty-four SSc patients with either diffuse (dSSc) or limited (lSSc) disease and 20 age- and sex-matched healthy controls (HCs) were examined. Fourteen patients were treated with prednisone and 9 patients with prednisone and cyclophosphamide pulses. Results showed that (1) IL-2 production is significantly decreased, whereas IL-10 is higher in untreated patients compared to HCs; IL-10, IFN-gamma, and TNF-alpha production is higher in lSSc compared to dSSc patients; (2) CD4+25+ (IL-2R), CD8+, and CD8+45RA-28+57- (memory) lymphocytes are reduced in patients compared to HCs; (3) CD95-expressing CD4+ and CD8+ cells are significantly higher in dSSc patients; and (4) steroids are more effective alone than in combination with cyclophosphamide in reducing IL-10 and IFN-gamma production in these patients. These results confirm that a complex imbalance in cytokine production is present in SSc patients and suggest that peculiar phenotypic populations are underrepresented in these patients. Overexpression of Fas in dSSc could results from the attempt of the immune system to induce apoptosis of autoreactive T-cell clones.

Aged↗
PubMed2024

Stroke genetics and how it Informs novel drug discovery.

INTRODUCTION: Stroke is one of the main causes of death and disability worldwide. Nevertheless, despite the global burden of this disease, our understanding is limited and there is still a lack of highly efficient etiopathology-based treatment. It is partly due to the complexity and heterogenicity of the disease. It is estimated that around one-third of ischemic stroke is heritable, emphasizing the importance of genetic factors identification and targeting for therapeutic purposes. AREAS COVERED: In this review, the authors provide an overview of the current knowledge of stroke genetics and its value in diagnostics, personalized treatment, and prognostication. EXPERT OPINION: As the scale of genetic testing increases and the cost decreases, integration of genetic data into clinical practice is inevitable, enabling assessing individual risk, providing personalized prognostic models and identifying new therapeutic targets and biomarkers. Although expanding stroke genetics data provides different diagnostics and treatment perspectives, there are some limitations and challenges to face. One of them is the threat of health disparities as non-European populations are underrepresented in genetic datasets. Finally, a deeper understanding of underlying mechanisms of potential targets is still lacking, delaying the application of novel therapies into routine clinical practice.

Humans↗