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Fragmentation of the Québec population genetic pool (Canada): evidence from the genetic contribution of founders per region in the 17th and 18th centuries.

The 6 million French-Canadians of Québec derive from a relatively small number of founders. Consequently, some hereditary diseases, which may or may not present a worldwide distribution, have been detected in high frequency in this population. Several studies, however, indicate a nonuniform distribution of these diseases through the population, suggesting that the French-Canadian founder effect has been geographically stratified. Here we explore this stratification by using a demographic database, the Population Register of Early Québec, that contains almost all birth, marriage, and death certificates (>712,000) recorded in parish registers between 1608-1800. In this database, every genealogical link has been traced back to the founders of the population, so that we can compute the genetic contribution of founder per region, and then account for the early events that have shaped the distribution of diseases. Ten regions, comprising varying numbers of parishes, have been selected. We first describe each region in terms of homogeneity and concentration of its gene pool. For this purpose, a new concept is introduced, the founders' uniform contribution number (FUN), i.e., the number of founders a population would have if all its founders had an equal contribution. Second, we estimate genetic similarity between regions on the basis of differential genetic contribution. To classify the regions, we use principal component and cluster analysis. Our results show a tripartite clustering of the population, and invite us to reconsider the results obtained from biomolecular and clinical studies, which show a bipartite clustering.

Adult↗

Prognostic significance of metastatic lymph node size in patients with gastric cancer.

BACKGROUND: Patients with gastric cancer that has metastasized to the lymph nodes are a heterogeneous population with a variable prognosis. Stratification of these patients into prognostic groups is necessary for optimal adjuvant therapy. METHODS: The study comprised 715 patients who had undergone curative resection of a gastric neoplasm. Lymph nodes were sectioned, stained with haematoxylin and eosin, and the diameter of the largest metastatic lymph node (MLN) was measured. Patients with metastatic nodes were divided into groups n1 and n2 according to the size of the MLN. The cut-off level was set at 7 mm by a two-sample log rank test; patients in group n1 had a MLN size of 7 mm or less and those in group n2 had a MLN of 8 mm or more. RESULTS: Patients were stratified into significant prognostic groups by both the Union International Contra la Cancrum (UICC) node (N) stage and MLN size (n group). The UICC N-stage subcategories were further divided into prognostic groups according to MLN size (n group). On multivariate analysis the MLN size remained independently significant in terms of overall and disease-free survival rates, and the UICC N stage was not significant, independently of the n group. Node-positive patients with fewer than 15 lymph nodes removed at operation could also be stratified into prognostic groups by the n group. Stratification according to the TNM stage and by MLN size was superior to existing UICC TNM staging. CONCLUSION: This new method may help clinicians to design a more appropriate treatment strategy for patients with gastric cancer.

Adult↗

Cardiac syndrome X and endothelial dysfunction: new concepts in prognosis and treatment.

Cardiac syndrome X (CSX), or angina with no flow-limiting stenosis on coronary angiogram, has been regarded as a condition with an excellent prognosis despite variable symptomatic improvement. Newer data show that patients with CSX with endothelial dysfunction have an increased risk for future adverse cardiac events. Current hypotheses of CSX pathophysiology emphasize a dysfunctional vascular endothelium that leads to microvascular ischemia. Treatments that target improving endothelial function, such as statins, angiotensin-converting enzyme inhibitors, estrogen, and lifestyle modification, are promising additions to treatment regimens for CSX. The goal of this article is to provide information for improved diagnosis, risk stratification, and therapy for the population with CSX.

Angiotensin-Converting Enzyme Inhibitors↗

Safety profile of a nicotine lozenge compared with that of nicotine gum in adult smokers with underlying medical conditions: a 12-week, randomized, open-label study.

BACKGROUND: Nicotine polacrilex lozenges deliver 25% to 27% more nicotine compared with equivalent doses of nicotine polacrilex gum. The increased nicotine exposure from the lozenge has raised questions about the relative safety of the lozenge and gum. OBJECTIVE: The objective of this study was to compare the safety profiles of the 4-mg nicotine lozenge and 4-mg nicotine gum in smokers with selected label-restricted diseases. METHODS: This was a multicenter, randomized, open-label study in adult smokers with heart disease, hypertension not controlled by medication, and/or diabetes mellitus. Patients were randomized in a 1:1 ratio to receive the 4-mg nicotine lozenge or 4-mg nicotine gum. Safety assessments were made at baseline and at 2, 4, 6, and 12 weeks after the start of product use. RESULTS: Nine hundred one patients were randomized to treatment, 447 who received the lozenge and 454 who received the gum (safety population). The majority were women (52.7%). Patients' mean age was 53.9 years, their mean weight was 193.9 pounds, and they smoked a mean of 25.2 cigarettes per day at baseline. Five hundred fifty-three patients, 264 taking the lozenge and 289 taking the gum, used the study product for > or =4 days per week during the first 2 weeks (evaluable population). The nicotine lozenge and nicotine gum were equally well tolerated, despite increased nicotine exposure from the lozenge. The incidence of adverse events in the 2 groups was similar during the first 2 weeks of product use (evaluation population: 55.3% lozenge, 54.7% gum), as well as during the entire study (safety population: 63.8% and 58.6%, respectively). Stratification of patients by sex, age, extent of concurrent smoking, extent of product use, and severity of adverse events revealed no clinically significant differences between the lozenge and gum. The most common adverse events were nausea (17.2% and 16.1%; 95% CI, -3.7 to 6.0), hiccups (10.7% and 6.6%; 95% CI, 0.5 to 7.8), and headache (8.7% and 9.9%; 95% Cl, -5.0 to 2.6). Serious adverse events were reported in 11 and 13 patients in the respective groups. Fewer than 6% of patients in either group were considered by the investigator to have a worsening of their overall disease condition during the study. The majority of patients (>60%) experienced no change in their disease status from baseline. CONCLUSION: The 4-mg nicotine lozenge and 4-mg nicotine gum had comparable safety profiles in these patients with label-restricted medical conditions.

Algorithms↗

Relationship of validated psychometric tools to subsequent medical utilization for asthma.

BACKGROUND: Risk stratification is used to identify patients with asthma at increased risk of experiencing morbidity and resource utilization. Validated psychometric tools are infrequently studied sources of data for this purpose. PURPOSE: To evaluate 4 types of validated psychometric tools as predictors for subsequent asthma utilization and determine their clinical usefulness. METHODS: Eleven hundred patients with active asthma from a Health Maintenance Organization completed surveys that included demographic information and validated psychometric tools measuring generic quality of life (physical and mental components), asthma-specific quality of life, asthma control, and asthma symptom severity. Survey records were linked to administrative data that captured emergency department and hospital care, short-acting beta-agonist, and oral corticosteroid utilization for the year of and the year following the survey. Relationships of survey variables with subsequent utilization were assessed, adjusting for both baseline demographic and asthma utilization factors. RESULTS: Scores of each psychometric tool were significantly related to subsequent utilization in univariate analyses and after adjusting for baseline utilization and demographic risk factors. Patients with higher scale-defined morbidity were as much as 4 times more likely to have subsequent utilization (sensitivity as high as 58%; specificity as high as 78%). Addition of an asthma-specific tool to either demographic or utilization prediction models added sensitivity (as much as 15%) but did not substantially improve the prediction properties of models containing both demographic and utilization predictors. CONCLUSION: Validated psychometric tools appear useful for asthma risk stratification in individuals and in populations in which both utilization and demographic predictors are not available.

Adolescent↗

Subjective cognition trajectories, Alzheimer biomarkers, and incident mild cognitive impairment.

BACKGROUND: Subjective cognitive decline is common in older adults and may represent an early clinical signal along the Alzheimer's disease continuum. The clinical relevance of longitudinal changes in subjective cognitive decline remains unclear. OBJECTIVES: To determine whether trajectories of self- or study partner-reported cognitive decline predict progression to mild cognitive impairment and reflect Alzheimer's disease-specific biological patterns. DESIGN, SETTING, PARTICIPANTS: Data were pooled from two observational cohorts. Cognitively unimpaired participants with baseline amyloid status, repeated assessments of subjective cognitive decline, and clinical follow-up were included. The study included 770 participants with a median follow-up of 5.0 years (interquartile range 4.0-7.0). MEASUREMENTS: Subjective cognitive decline was assessed using the Everyday Cognition questionnaire completed by participants and study partners. Linear mixed-effects models examined associations with amyloid status and progression to mild cognitive impairment. Cox proportional hazards models tested whether one-year changes predicted progression. RESULTS: Amyloid-positive participants and those who progressed to mild cognitive impairment showed steeper increases in self- and study partner-reported cognitive difficulties over time. Among amyloid-positive participants, only increases in study partner-report differentiated progressors from non-progressors. One-year increases in study partner-report predicted a higher risk of mild cognitive impairment compared with unchanged scores (hazard ratio 3.24; 95% confidence interval 1.73-6.07]), with effects confined to amyloid-positive participants. CONCLUSIONS: Short-term increases in study partner-reported cognitive difficulties identify amyloid-positive cognitively unimpaired older adults at increased risk of near-term progression to mild cognitive impairment. Longitudinal monitoring using study partner reports may provide a low-burden and clinically relevant approach for early risk stratification and surveillance in aging populations.

Humans↗

hOGG1 Ser326Cys polymorphism and breast cancer risk among Asian women.

To evaluate the potential association between breast cancer risk and Ser326Cys polymorphism of hOGG1 gene, encoding for an enzyme involved in the base excision repair of 8-hydroxyguanine, hospital based case-control studies were conducted in two Asian populations consisting of 475 breast cancer cases (271 Korean and 204 Japanese) and 500 controls (314 Korean and 186 Japanese). PCR-based methods were employed for the genotyping analyses and the statistical evaluations were performed by unconditional logistic regression model. The frequency of hOGG1 Ser/Ser, Ser/Cys, and Cys/Cys genotypes were 22.5, 48.7, and 28.8% in all cases, and 23.7, 52.1, and 24.1% in the controls. No statistically significant associations between the genotypes and breast cancer risk were observed, neither when the ethnic groups were examined separately nor when the total study population was included. Neither did stratification by menopausal status reveal any association between hOGG1 genotypes and breast cancer. Our novel findings therefore suggest that hOGG1 Ser326Cys polymorphism is unlikely to play a modifying role in individual susceptibility to breast cancer among Asian women.

Adult↗

Research methodology for studies of prayer and distant healing.

The double-blind randomized clinical trial is the gold standard for trials of prayer and distant healing. Adequate blinding and randomization procedures should be followed and documented. The intervention must be well defined (include frequency, amount of time and training and/or experience level of healers). Subjects should have risks and benefits of study participation explained to them and sign informed consent before enrollment. Populations should be homogeneous. Consider stratification for smaller samples. Baseline information, including psychological status, beliefs about prayer and healing and other sources of prayer and healing, should be collected from subjects in clinical trials. This should be examined as part of the final data analysis for contribution to outcomes. Objectively measurable outcomes with adequate variability should be chosen. Subject study participation activities such as clinical interviews, traveling to special sites. journaling or meditation should be minimized to avoid washing out a small effect. In clinical trials subjects should be asked if they believed they were in the treatment group and this information should be entered as a co-variate for data analysis. Healers/prayers should be treated in a collegial and respectful way. Their healing efforts (time. location, method) should be documented in a log and they should be periodically contacted and encouraged by experimenters if the study' is taking place over an extended period of time. Observational and outcomes research can add an important dimension to healing research. Qualitative studies may also make an important contribution and help guide development of future controlled trials.

Attitude to Health↗

RUMINA: high-throughput deduplication of unique molecular identifiers for amplicon and whole-genome sequencing with enhanced error correction.

MOTIVATION: Unique molecular identifiers (UMIs) are widely used in next-generation sequencing to enable accurate molecular counting and error correction. However, challenges remain in accurately collapsing UMI clusters, especially when read counts are low or sparse read clusters arise from barcode sequencing errors. RESULTS: We present RUMINA, a Rust-based pipeline for UMI-aware deduplication and error correction, optimized for both amplicon and shotgun sequencing. RUMINA supports multiple UMI cluster strategies, alongside majority-rule read selection independent of mapping quality, as well as discrete handling of 1-2 read clusters, paired-end merging, and read-length stratification. Benchmarking using simulated HIV population sequencing data and real-world iCLIP and TCR datasets showed that RUMINA improves ultra-low frequency SNV detection (0.01%-1%), reduces false positives, enhances reproducibility, and processes sequencing data up to 10-fold faster than existing tools. By integrating UMI- and sequence-level correction in a high-performance framework, RUMINA offers a fast, scalable, and robust solution for UMI-enabled sequencing workflows. AVAILABILITY AND IMPLEMENTATION: RUMINA is implemented in Rust and distributed as open-source code and precompiled binaries. Source code and installation instructions are available at https://github.com/greninger-lab/rumina. Documentation associated with this manuscript is available at https://github.com/greninger-lab/rumina_paper.

High-Throughput Nucleotide Sequencing↗

Effects of an assessment of needs for medical and social services on long-term mortality: a randomized controlled study.

BACKGROUND: The aim of this study was to investigate the long-term effects of one general health screening on mortality. METHOD: After stratification and randomization of a population of 450,000 inhabitants, two groups were formed, an intervention group of 3064 people and a control group of 29,122 people. From the National Cause of Death Register, data were collected as regards death and causes of deaths for 1970-1990. RESULTS: Multivariate analysis was used to correct for known confounders. We then found no differences between the groups regarding deaths from all causes, cardiovascular diseases, cancer or accidents and poisoning. CONCLUSIONS: One general health screening seems to have little, if any value in preventing fatal diseases.

Adolescent↗

Psoriatic arthritis in psoriatic patients.

One hundred and eighty patients with psoriasis have been studied in the Neapolitan area to find the prevalence of arthritis in psoriasis. Wright and Moll's criteria for the diagnosis of arthritis were applied. Of 180 psoriatic patients, 62 exhibited arthritis (34.4% of total cases) According to Moll and Wright's five broad clinical forms of arthritis, the following distribution was found: polyarticular in 38.7% of arthritic patients, mono-oligoarticular in 16.1%, distal interphalangeal in 7.5%, deforming or mutilans in 2.3% and spondylitic and/or sacro-iliitic in 20.9%. In 14.5% of arthritic patients an overlap of the spondylitic form and peripheral involvement was also found. Stratification by age of patient populations shows that cutaneous pathology has a homogeneous distribution in the various age decades, while joint symptoms are seen maximally in the sixth decade and are absent in the first two decades. The relationship between the onset of skin lesions and joint pathology demonstrates that skin lesions preceded arthritis in 64.5% of the cases, whilst arthritis antedated psoriasis in only 19.35%. In 16.1% of cases psoriasis and arthritis began almost simultaneously. Nail changes were present in 63% of arthritic patients and in 37% of psoriatic subjects without arthritis. Furthermore, in 88% of arthritic patients in whom arthritis preceded skin lesions, nail changes antedated the onset of clinically apparent psoriasis. Extra-articular features were not found. This absence might be associated with the usual seronegativity for rheumatoid factor in psoriatic arthritis, also confirmed in this survey.

Adolescent↗

A conditional inference framework for extending the transmission/disequilibrium test.

The transmission/disequilibrium test (TDT) of Terwilliger and Ott [Hum Hered 1992;42:337-346] and Spielman et al. [Am J Hum Genet 1993;52:506-516] is widely used to detect linkage and/or association between a genetically influenced disease and the alleles of a codominant marker locus. The TDT was specifically designed to avoid the spurious population associations produced by ethnic stratification of a sample of affected people. In this paper, we describe permutation extensions of the TDT that share this advantage. Our conditional inference framework permits extensions to multiple alleles, multiple loci, unaffected siblings, and genotypic rather than allelic associations. In the case of multiple loci, the conditional perspective provides a straightforward correction for multiple tests that can be substantially more powerful than the standard Bonferroni correction.

Alleles↗

Individualized pharmacogenetic therapy: a critical analysis.

OBJECTIVE: Individualized, or personalized, therapy is highlighted as the declared goal of pharmacogenetics. In this paper, the content and significance of the individualization concept are analyzed. METHOD: Our analysis is based on a systematic reading of the current literature pertinent to pharmacogenetics. RESULTS: This analysis reveals that the pharmacogenetic understanding of individualization is based on a biomechanistic paradigm. In contrast to a notion of individualized therapy based on a biopsychosocial paradigm, this biomechanistic concept does not provide for individualization in psychosocial terms, but instead leads to the stratification and classification of patient populations. This finding does not necessarily cast doubt on the efficacy of pharmacogenetics, but does call its underlying ideology into question. CONCLUSION: The term 'individualization of therapy' does not reflect the real potential of pharmacogenetics, but instead represents a widely used and theoretically unjustified publicity slogan.

Humans↗

Clinical pharmacological and therapeutic considerations in general intensive care. A review.

The application of clinical pharmacological concepts and therapeutic standards in intensive care settings presents particularly difficult problems due to the lack of adequately controlled background information and the highly variable and rapidly evolving clinical conditions where drugs must be administered and their impact evaluated. In this review, an attempt has been made to discuss the available knowledge within the framework of a problem-oriented approach, which appears to provide a more clinically useful insight than a drug-centred review. Following a brief discussion of the scanty data and the most interesting models to which reference can be made from a pharmacokinetic point of view (the burn patient being taken as an example), the review concentrates on the main general intervention strategies in intensive care patients. These are based mainly on non-pharmacological measures (correction of fluid and electrolyte balance, total parenteral nutrition, enteral nutrition, oxygenation and ventilatory management) and are discussed with respect to the specific challenge they present in various clinical conditions and organ failure situations. In addition, 4 major selected clinical conditions where general management criteria and careful use of prophylactic and therapeutic drug treatments must interact to cope with the variety of presentations and problems are reviewed. These include: acute cerebral damage; anti-infective prophylaxis and therapy; cardiovascular emergencies; and problems of haemostasis. Each problem is analysed in such a way as to frame the pharmacological intervention in its broader context of the underlying (established or hypothesised) pathophysiology, with special attention being paid to those methodological issues which allow an appreciation of the degree of reliability of the data and the recommendations which appear to be practiced (often haphazardly) in intensive care units. The thorough review of the published literature provided (up to mid-1986) clearly shows that in this field the quality of randomised controlled and epidemiological studies is rather unsatisfactory. It would be highly beneficial to research and to clinical care if larger multicentric protocols and prospective epidemiological comparative investigations could be carried out to investigate more timely and adequately the variables which determine drug action, and the final outcome in the many subgroups of patients which must be considered in a proper stratification of intensive care unit populations.

Critical Care↗

(133)Xe SPECT cerebral blood flow study in a healthy population: determination of T-scores.

UNLABELLED: Dementia is becoming a major health problem as the population of the Northern Hemisphere ages. Early differential diagnosis between normal cognitive decline and dementia is particularly difficult. If psychometric evaluation can contribute to the diagnosis, quantitative cerebral functional imaging would play an important role. We therefore proposed, first, to constitute a normative dataset that could later be used to identify subjects at risk for neurodegenerative processes and, second, to describe the risk of abnormal global cerebral blood flow (gCBF) by defining categories based on the standardized cutoff scores of a young, healthy population (T-score). METHODS: Of a total of 203 healthy volunteers, 187 were included in the protocol, which included evaluation of medical history, neurologic and neuropsychologic status, and body composition; analysis of blood; and measurement of gCBF by means of (133)Xe SPECT. RESULTS: With ANOVA analysis using age and sex as between-subject factors and gCBF as a within-subject factor, a significantly higher gCBF was found in women than in men. In addition, a linear reduction as a function of age was observed for both sexes (-0.3%/y). T-score was determined for the 18- to 28-y-old age group, for whom gCBF was found to be 46.7 +/- 5.1 mL/min/100 g tissue in men and 49.0 +/- 5.0 mL/min/100 g tissue in women. The age-dependent decrease could thus be expressed in T-scores and, in the 29- to 38-y-old, 39- to 48-y-old, and >48-y-old age groups, averaged -0.63, -1.29, and -1.92, respectively, in men and -0.63, -0.83, and-2.40, respectively, in women. Cognitive performance, body composition, and blood analysis revealed the expected significant effects from sex and age. CONCLUSION: The large-scale reference database of gCBF measurements constituted from a healthy, well-controlled population enabled age and sex stratification, which showed significant differences between the sexes and a significant decline as a function of age. T-scores were determined and warrant further studies on the prospective identification of early dementia by (133)Xe SPECT in elderly individuals.

Adolescent↗

[Arterial hypertension management in general practice in France according to global risk factors].

OBJECTIVE: The absolute benefit of antihypertensive medications increases with the level of cardiovascular risk. Moreover in high risk groups, it has been demonstrated that tight blood pressure (BP) control conferred a substantial reduction in the risk of cardiovascular events compared to less tight BP control. Taking into accounts these data, the WHO guidelines recommend to achieve normal BP in high risk subjects. The aim of the study was to assess BP control in a large population of hypertensives (HT) after stratification by cardiovascular risk. METHODS: 15,514 HT defined as office BP > or = 140/90 or the presence of antihypertensive treatment were recruited in France by 3,152 general practitioners. Cardiovascular risk factors and office BP were recorded. Controlled hypertension was defined as a BP < 140/90 mmHg. In patients free of cardiovascular disease, 10-year cardiovascular risks were calculated on the basis of the equations derived from the Framingham Study. RESULTS: 10-year risks were available in 13,560 HT. Those in the highest quartile had greater body mass index (BMI) and the highest concentration of diabetics and current smokers (upper quartile versus lower quartile: BMI: 28.15 vs 26.51 kg/m2; diabetics: 45% vs 3%; current smoking 32% vs 12%; p < .001). [table: see text] Increasing quartiles of risk were associated with the prevalence of uncontrolled hypertension and at a lesser extent with the use of combination therapy. Subjects in the upper quartile had more frequent calcium-blockers, ACE inhibitors and diuretics use and a less frequent betablocker use. CONCLUSION: In general practice, 85% of hypertensives at highest risk are uncontrolled whereas half of them are under monotherapy. An antihypertensive strategy based on global risk may improve BP control in high risk patients.

Adult↗

Detection of risk groups in myelodysplastic syndromes. A multicenter study.

BACKGROUND AND OBJECTIVES: Myelodysplastic syndromes (MDS) comprise a group of heterogeneous hematologic disorders with risk of leukemic evolution (LE). The French-American-British (FAB) co-operative group classifies them into five morphologic entities and the International Prognostic Scoring System (IPSS) proposes four groups of risk on the basis of clinical and cytogenetic variables. The aim of this study was to evaluate the application of the IPSS in our Argentine population, to test the prognostic value of its variables and to determine whether this score helps to associate prognostic subgroups of risk into FAB subtypes. DESIGN AND METHODS: Two hundred and thirty-four patients with primary MDS and a median follow-up of 28 months were evaluated using univariate analyses to determine median survival (SV) and the time to LE. The variables analyzed were FAB classification, IPSS, percentage of myeloblasts, cytogenetic groups of risk and number of cytopenias. RESULTS: Univariate analyses showed that all variables analyzed were predictive for SV and for LE in our MDS population. Application of the IPSS allowed discrimination into the 4 groups of risk and helped to identify prognostic subclasses among the FAB classification, associating 5%, 15% and 19% of cases with worse prognosis within the FAB classification of refractory anemia (RA), RA with ringed sideroblasts and RA with excess of blasts (RAEB), respectively. The IPSS was not informative for RAEB in transformation cases and would not be applied to patients with chronic myelomonocytic leukemia. INTERPRETATION AND CONCLUSIONS: This score could be applied to our MDS population, showing no geographic differences. Stratification of FAB patients according to IPSS would be helpful to develop risk-adapted therapeutic strategies.

Adolescent↗

Yield of hypothyroidism in symptomatic primary care patients.

Symptoms suggestive of hypothyroidism are common in primary care practice, but the yield of this disorder from symptom-based testing has not been adequately evaluated. We attempted to determine this yield and examine the effect of various patient factors on its magnitude. The records of 982 consecutive primary care health maintenance organization patients who had a thyroid-stimulating hormone (TSH) determination for suspicion of hypothyroidism were reviewed. Forty-two (4.3%) had an increased TSH concentration on initial testing, but only 17 (1.7%) had a TSH level 5 mU/L or more above normal. Abnormal thyroid examination results and white vs black race were independently associated with a TSH concentration 5 mU/L or more above normal. Female sex and age did not significantly affect the odds of an elevated TSH concentration. The yield of hypothyroidism from symptom-based testing in this setting was quite low. Although increasing age and female sex are both strong determinants of the risk of hypothyroidism in the general population, neither factor permitted risk stratification in symptom-based testing. The strong racial association noted was not anticipated and requires confirmation.

Adult↗