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L Joseph

Publications and source records attributed to L Joseph.

At least 37 records · Page 2Linked to original sources

Tattooing and transfusion-transmitted diseases in Brazil: a hospital-based cross-sectional matched study.

BACKGROUND: Presence of tattoos has been a criterion for temporary deferral of blood donors. Scientific evidence remains equivocal regarding the association between tattooing and transfusion-transmitted diseases (TTDs). METHODS: A cross-sectional matched study was undertaken among adults attending a Brazilian hospital and blood bank. The exposure of interest was having at least one permanent tattoo, and the outcomes were the presence of serological markers for the following TTDs: hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections, syphilis, and Chagas' disease. Exposed and unexposed subjects were matched on age, sex, and main clinical complaint. Associations were assessed by odds ratios (ORs), adjusted for confounders by unconditional logistic regression. FINDINGS: The study recruited 345 subjects, 182 with tattoos. Having a tattoo was associated with HCV (OR: 6.41; 95% confidence interval (CI) 1.29, 31.84), and with having at least one positive test for any TTD (OR: 2.05, 95% CI: 1.11, 3.81). No statistically significant associations were found between tattooing and HBV or HIV infection, syphilis or Chagas' disease, but these results are inconclusive given the large CI obtained. INTERPRETATION: Having a tattoo is not an important indicator for testing positive for a TTD, except for HCV infection. Taking into consideration the increasing prevalence of tattooing in the general population, the absolute need of a safe and sustainable blood supply and optimization of the cost-effectiveness of screening blood donors, further research on tattoos is urgently required.

Adolescent↗

Associations among disease conditions, bone mineral density, and prevalent vertebral deformities in men and women 50 years of age and older: cross-sectional results from the Canadian Multicentre Osteoporosis Study.

This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.

Aged↗

Unravelling a biogeographical knot: origin of the 'leapfrog' distribution pattern of Australo-Papuan sooty owls (Strigiformes) and logrunners (Passeriformes).

Molecular analysis of two Australo-Papuan rainforest birds exhibiting correlated 'leapfrog' patterns were used to elucidate the evolutionary origin of this unusual pattern of geographical differentiation. In both sooty owls (Tyto) and logrunners (Orthonyx), phenotypically similar populations occupy widely disjunct areas (central-eastern Australia and upland New Guinea) with a third, highly distinctive population, occurring between them in northeastern Queensland. Two mechanisms have been proposed to explain the origin of leapfrog patterns in avian distributions: recent shared ancestry of terminal populations and unequal rates or phenotypic change among populations. As the former should generate correlated patterns of phenotypic and genetic differentiation, we tested for a sister relationship between populations from New Guinea and central-eastern Australia using nuclear and mitochondrial DNA sequences. The resulting phylogenies not only refute recent ancestry as an explanation for the leapfrog pattern, but provide evidence of vastly different spatio-temporal histories for sooty owls and logrunners within the Australo-Papuan rainforests. This incongruence indicates that the evolutionary processes responsible for generating leapfrog patterns in these co-distributed taxa are complex, possibly involving a combination of selection and drift in sooty owls and convergence or retention of ancestral characteristics in logrunners.

Adenosine Triphosphatases↗

Tattooing and risk for transfusion-transmitted diseases: the role of the type, number and design of the tattoos, and the conditions in which they were performed.

Tattoos have been shown to be associated with transfusion-transmitted diseases (TTDs), particularly hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. Very little is known about the association between different categories of tattoos and TTDs. In a cross-sectional study in Brazil, we studied 182 individuals with tattoos and assessed the odds of testing positive for a TTD according to tattoo type, number, design and performance conditions. Major findings were significant associations between an increasing number of tattoos and HBV infection (odds ratio (OR) of 2.04 for two tattoos and 3.48 for > or = 3 tattoos), having a non-professional tattoo and testing positive for at least one TTD (OR = 3.25), and having > or = 3 tattoos and testing positive for at least one TTD (OR = 2.98). We suggest that non-professional tattoos and number of tattoos should be assessed as potential deferral criteria in screening blood donors.

Adolescent↗

An audit of the accuracy of fine needle aspiration using a liquid-based cytology system in the setting of a rapid access breast clinic.

We have assessed the effectiveness and accuracy of reporting fine needle aspirates of the breast (FNAB) using a liquid-based cytology (LBC) system (the Cytospin) method) in the pressure situation of a rapid access clinic (RAC). We have reviewed every case from the RAC from June 1997 to February 2001 inclusive. There were 1322 cases, which accounted for 26% of the total FNAB received in our department over the period. There were 323 cancers and 999 benign cases in the group. The inadequate/nondiagnostic rate (C1) was 18%. The absolute sensitivity, including C1 cases, was 73% with the complete sensitivity being 90%. The groups of 'atypical, probably benign' (C3) and 'suspicious, probably malignant' (C4) accounted for a total of 6.2%. There were 28 false negative cases and 1 false positive case (a borderline phyllodes tumour). Comparing our results with the standards recommended by the NHSBSP has shown that the diagnosis of FNAB using this LBC method is feasible, accurate and reliable even in the pressure situation of a RAC.

Ambulatory Care Facilities↗

Reconciling genetic expectations from host specificity with historical population dynamics in an avian brood parasite, Horsfield's Bronze-Cuckoo Chalcites basalis of Australia.

Mitochondrial DNA (mtDNA) is being used increasingly to explore the evolution of host specificity in avian brood parasites. A stable coevolutionary equilibrium between multiple phylogenetically unrelated hosts and a brood parasitic species predicts that mtDNA diversity in the parasite should be relatively deep and phylogenetically structured. Also, the different intraspecific clades resulting from parasitism to multiple sympatric hosts should themselves occur sympatrically. However, mtDNA diversity in brood parasites is as susceptible to effects of historical population dynamics as in any species. We demonstrate the relevance of these dynamics to the use of mtDNA in understanding coevolution between an Australian brood-parasite, Horsfield's Bronze-Cuckoo Chalcites basalis and its hosts, Malurus fairy-wrens and Acanthiza thornbills. Previous ecological and behavioural analyses argue that Malurus- and Acanthiza-specific host races exist in C. basalis. Yet mtDNA diversity in C. basalis is low and phylogenetically unstructured (mean sequence divergence 0.15 +/- 0.07%, range 0.00%-0.31%) and tests of mtDNA neutrality and range expansion vs. population stability (Tajima's D, Fu & Li's F* and D*, Fu's F(S), mismatch analyses) all indicate that C. basalis has expanded its range very recently, probably within the last few tens of thousands of years following climatic amelioration after a peak of aridity in the late Pleistocene. The low mtDNA diversity and its lack of phylogenetic structure in C. basalis deny the existence of evolutionarily long-term stable host races in C. basalis but not the possibility of recently evolved ones. They highlight the need for renewed behavioural and ecological study of the relationship between C. basalis and its hosts. Our findings illustrate the need to understand the evolutionary context in which a brood parasite and its hosts have evolved if mtDNA data are to be used in testing hypotheses concerning the origin and maintenance of host specificity. They also add to the growing body of work illustrating the use of mismatch analyses and Fu's F(S) in detecting range expansions.

Animals↗

Cytokines in coagulation and thrombosis: a preclinical and clinical review.

The cytokine network is a complex and dynamic system, involved in numerous biological responses in the human body. This review of the current literature describes the role of cytokines and their interaction with the coagulation system, specifically in the maintenance of the thrombo-hemorrhagic balance in vivo in human subjects and in animals. In general, cytokines are thrombogenic, but they are amenable to therapeutic manipulations and hence are a potentially attractive tool in the clinician's armamentarium. Studies of the effects of cytokines in vivo are difficult because cytokines act in a very finite microenvironment and, although their actions are significant, they are transient. Most of the available clinical data related to interactions between cytokines and the coagulation system focuses on the role of tumor necrosis factor-alpha and interleukin-1 in septicemia and septic shock. However, several other cytokines and related proteins, such as platelet activating factor and plasminogen activator inhibitor, are also known to influence coagulation and thrombosis. These factors interact closely with cytokines, and have been included in this review for a better understanding of their interactions with traditional cytokines. Studies that utilize cell culture systems do not accurately model the in vivo status of this complex system and, hence, this review has excluded such studies. The role of the cytokine network in coronary artery disease, angiogenesis, or neoplasia has been addressed elsewhere by other workers and is not discussed here. By emphasizing important in vivo interactions, the intention of this review is to serve as an impetus to further translational research, both clinical and in the laboratory.

Blood Coagulation↗

Oral contraceptive use and bone mineral density in premenopausal women: cross-sectional, population-based data from the Canadian Multicentre Osteoporosis Study.

BACKGROUND: Positive and negative effects on bone mineral density (BMD) have been described as a result of the premenopausal use of oral contraceptives (OCs); increased fracture rates have also been reported. This study assessed the relation between OC use and BMD in a population-based, 9-centre, national sample of women aged 25-45 years. METHODS: Premenopausal women who had been enrolled in the Canadian Multicentre Osteoporosis Study were classified as having ever been OC users (> or = 3 months) or as having never been OC users (0 to < 3 months). Data were obtained through extensive questionnaires and measuring of participants' weight, height and the BMD of lumbar vertebrae and the proximal femur. RESULTS: Of the sample of 524 women, whose mean age was 36.3 (standard deviation [SD] 5.9) years, 454 had used OCs; their mean age when they started using OCs was 19.8 (SD 3.5) years and the mean duration of use was 6.8 (SD 4.8) years. Women who had ever and those who had never used OCs showed no differences in age, age at menarche, parity, current calcium intake, exercise, body mass index (BMI), education, past irregular cycles or amenorrhea. OC users reported more alcohol and cigarette use and more use of medications to create regular cycles. Mean BMD values (adjusted for age, BMI and height) were 0.02-0.04 g/cm2 (that is, 2.3%-3.7%) lower in OC users, and were significantly lower in the spine and trochanter. The BMD of the spine in OC users was 1.03 (SD 0.12) g/cm2 versus 1.07 (SD 0.12) g/cm2 (95% confidence interval [CI] of difference -0.07 to -0.001) in those who had never used OCs. BMD was neither related to the duration of OC use nor to gynecological age at first use. Current and past users had similar BMD values. INTERPRETATION: National, population-based data show lower BMD values for the trochanter and spine in premenopausal women who have used OCs compared with those who have never used OCs.

Absorptiometry, Photon↗

Evaluation of decision rules for referring women for bone densitometry by dual-energy x-ray absorptiometry.

CONTEXT: Identification of women with low bone mineral density (BMD) is an important strategy in reducing the incidence of osteoporotic fractures. However, screening all women is not recommended. OBJECTIVES: To assess the diagnostic properties of 4 decision rules--Simple Calculated Osteoporosis Risk Estimation (SCORE), Osteoporosis Risk Assessment Instrument (ORAI), Age, Body Size, No Estrogen (ABONE), and body weight less than 70 kg (weight criterion)--for selecting women for dual-energy x-ray absorptiometry (DXA) testing and to compare results with recommendations made in the National Osteoporosis Foundation (NOF) practice guidelines. DESIGN AND SETTING: Analysis of data from the Canadian Multicentre Osteoporosis Study, a population-based community sample, collected from 9 study centers across Canada between February 1996 and September 1997. PARTICIPANTS: Postmenopausal women aged 45 years or older (N = 2365) without bone disease who had DXA data for the femoral neck, data to apply selection criteria, and who were not currently taking estrogens or who had been taking hormone replacement therapy for 5 or more years. MAIN OUTCOME MEASURES: Sensitivity, specificity, and area under the receiver operating characteristic (AUROC) curve of each of the 4 decision rules and the NOF guidelines for identifying women with a BMD T score of less than -1.0 SD, less than -2.0 SD, and no more than -2.5 SD at the femoral neck, and percentages of women recommended for testing, stratified by BMD level and age. RESULTS: The percent of women with a BMD T score less than -1, less than -2, and no more than -2.5 were 68.3%, 25.4%, and 10.0%, respectively. The AUROC curves were greatest using SCORE and ORAI. The sensitivity for identifying women with a BMD T score of less than -2.0 was 93.7% (95% confidence interval [CI], 91.8%-95.6%) using the NOF guidelines and was 97.5% (95% CI, 96.3%-98.8%), 94.2% (95% CI, 92.3%-96.1%), 79.1% (95% CI, 75.9%-82.3%), and 79.6% (95% CI, 76.4%-82.8%), respectively, using the SCORE, ORAI, ABONE, and weight criterion. However, the NOF guidelines also resulted in 74.4% (95% CI, 71.3%-77.6%) of women with a normal BMD (T score of -1.0 or higher) being tested compared with 69.2% (95% CI, 65.9%-72.5%), 56.3% (95% CI, 52.7%-59.8%), 35.8% (95% CI, 32.4%-39.2%), and 38.1% (95% CI, 34.6%-41.6%), respectively, using the 4 decision rules. Assessments suggest that ABONE and weight criterion are not useful case-finding approaches. CONCLUSION: The SCORE and ORAI decision rules are better than the NOF guidelines at targeting BMD testing in high-risk patients. The acceptability of these rules in clinical practice merits further investigation given their potential effect on the use of densitometry services.

Absorptiometry, Photon↗

Beta-blockers in congestive heart failure. A Bayesian meta-analysis.

PURPOSE: Congestive heart failure is an important cause of patient morbidity and mortality. Although several randomized clinical trials have compared beta-blockers with placebo for treatment of congestive heart failure, a meta-analysis quantifying the effect on mortality and morbidity has not been performed recently. DATA SOURCES: The MEDLINE, Cochrane, and Web of Science electronic databases were searched from 1966 to July 2000. References were also identified from bibliographies of pertinent articles. STUDY SELECTION: All randomized clinical trials of beta-blockers versus placebo in chronic stable congestive heart failure were included. DATA EXTRACTION: A specified protocol was followed to extract data on patient characteristics, beta-blocker used, overall mortality, hospitalizations for congestive heart failure, and study quality. DATA SYNTHESIS: A hierarchical random-effects model was used to synthesize the results. A total of 22 trials involving 10 135 patients were identified. There were 624 deaths among 4862 patients randomly assigned to placebo and 444 deaths among 5273 patients assigned to beta-blocker therapy. In these groups, 754 and 540 patients, respectively, required hospitalization for congestive heart failure. The probability that beta-blocker therapy reduced total mortality and hospitalizations for congestive heart failure was almost 100%. The best estimates of these advantages are 3.8 lives saved and 4 fewer hospitalizations per 100 patients treated in the first year after therapy. The probability that these benefits are clinically significant (>2 lives saved or >2 fewer hospitalizations per 100 patients treated) is 99%. Both selective and nonselective agents produced these salutary effects. The results are robust to any reasonable publication bias. CONCLUSIONS: beta-Blocker therapy is associated with clinically meaningful reductions in mortality and morbidity in patients with stable congestive heart failure and should be routinely offered to all patients similar to those included in trials.

Adrenergic beta-Antagonists↗

A randomized management study of impedance plethysmography vs. contrast venography in patients with a first episode of clinically suspected deep vein thrombosis.

OBJECTIVES: In this randomized management study, we examined the safety of withholding anticoagulation on the basis of negative impedance plethysmography (IPG) compared to negative contrast venography (CV) in symptomatic patients with a first episode of clinically suspected deep vein thrombosis (DVT), and we determined the impact of the limitations of IPG or CV on their clinical utility. METHODS: Patients at a university teaching hospital presenting with a first episode of clinically suspected DVT were randomized to one of two management strategies at study entry: (1) IPG: if positive, confirmatory CV was performed. If CV was positive, anticoagulants were administered, if CV was negative, anticoagulants were held. If negative, IPG was repeated serially and if it remained negative, anticoagulants were held (n = 165). (2) CV: if positive, anticoagulants were administered, if negative, anticoagulants were held (n = 159). The negative predictive value (NPV) of IPG and CV, positive predictive value (PPV) of IPG, and the failure rate of each strategy were assessed. RESULTS: Among IPG patients, 28 of 37 with positive IPG initially or during serial testing and evaluable CV had confirmed DVT (PPV 76%; 95% confidence interval, CI [62%, 90%]). DVT was diagnosed during serial testing in 2.1% of patients with initially negative IPG who completed testing. The NPV overall of negative IPG was 98.3%. During follow-up, two patients in the IPG group (1.2%) and two patients in the CV group (1.3%) developed venous thromboembolism (VTE). Death during follow-up occurred in 11% of IPG patients compared to 6% of CV patients (P =.13) The investigation strategy failed in 25% of IPG patients and in 14% of CV patients. CONCLUSIONS: Our findings demonstrate that the two diagnostic strategies we studied are equivalent methods for ruling out DVT in patients with a first episode of suspected DVT. The PPV of IPG was too low to permit its use alone as a test to rule in DVT. Both strategies had surprisingly high failure rates.

Adult↗

Consent to the use of stored DNA for genetics research: a survey of attitudes in the Jewish population.

The use of anonymized stored tissue is a routine practice in genetic research. Investigators who utilize stored samples are neither required nor able to obtain informed consent before each use. Many genetic studies, however, are conducted on specific ethnic populations (e.g., Ashkenazi Jews). The results in these cases, although individually anonymous, are not anonymous with respect to the ethnicity of the participants. This lack of group anonymity has led to concern about the possibility of stigmatization and discrimination based on the results of the genetic research. In the present study we surveyed Jewish individuals about their attitudes regarding the practice of using stored DNA samples for genetic research. Specifically, we were interested in whether attitudes about informed consent and willingness to participate in genetics research using stored DNA would depend on the circumstances in which the material was collected (i.e., clinical setting vs. research setting) and the characteristics of the disease or trait under investigation. Overall, most respondents reported that written informed consent should be required and that they would be willing to provide such consent. Participants were most willing to provide consent, however, when the sample had been collected in a research rather than clinical setting. Further, participants were more likely to endorse the need for obtaining consent when the sample was collected in a clinical setting. Finally, participants were significantly less willing to participate in research that examined stereotypical or potentially stigmatizing traits as opposed to research that examined medical or mental illnesses.

Adolescent↗

Localized herpes simplex lymphadenitis mimicking large-cell (Richter's) transformation of chronic lymphocytic leukemia/small lymphocytic lymphoma.

We report a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who presented with rapid enlargement of a cervical lymph node due to localized herpes simplex lymphadenitis, which was clinically indistinguishable from large cell (Richter's) transformation. The diagnosis was made by excisional lymph node biopsy, which demonstrated CLL/SLL and zonal necrosis due to herpes simplex infection. The herpetic zone was surrounded by a brisk proliferation of immunoblasts. This case demonstrates the need for excisional biopsy and histologic examination of rapidly enlarging nodes in patients with CLL/SLL. The diagnosis of herpes simplex lymphadenitis in patients with CLL/SLL is especially important because, unlike large cell transformation, the infection usually responds well to treatment.

Biopsy↗

Genetic variation and population structure in Oryza malampuzhaensis Krish. et Chand. endemic to Western Ghats, South India.

Oryza malampuzhaensis Krish. et Chand. (2n = 4x = 48; Poaceae, Oryza) is endemic to Western Ghats, South India, and shows a highly localized distribution over a small geographical area in this region. This is the most poorly understood taxon in genus Oryza and is often misidentified as O. officinalis owing to their close morphology. We assessed the nature and distribution of genetic variation among 11 populations of O. malampuzhaensis using random amplified polymorphic DNA markers. The analysis revealed low genetic variation in O. malampuzhaensis. Cluster analysis of pairwise genetic distances of populations revealed three distinct clusters and the grouping of populations largely corresponded to their geographical proximity. Restricted gene flow and a geography-dependent differentiation were evident among populations. The altitude-influenced differences in ecological factors among the natural habitats of the populations seem to be the cause of the geography-dependent differentiation. Genetically isolated smaller populations and a narrow genetic base in O. malampuzhaensis point to its vulnerability to genetic drift and genetic depauperation. Thus O. malampuzhaensis appears to be under the threat of extinction and needs to be conserved by use of suitable methods. The present study also identified molecular markers diagnostic for O. malampuzhaensis.

Altitude↗

The influence of osteoporotic fractures on health-related quality of life in community-dwelling men and women across Canada.

Health-related quality of life (HRQL) was examined in relation to prevalent fractures in 4816 community-dwelling Canadian men and women 50 years and older participating in the Canadian Multicentre Osteoporosis Study (CaMos). Fractures were of three categories: clinically recognized main fractures, subclinical vertebral fractures and fractures at other sites. Main fractures were divided and analyzed at the hip, spine, wrist/forearm, pelvis and rib sites. Baseline assessments of anthropometric data, medical history, therapeutic drug use, spinal radiographs and prevalent fractures were obtained from all participants. The SF-36 instrument was used as a tool to measure HRQL. A total of 652 (13.5%) main fractures were reported. Results indicated that hip, spine, wrist/forearm, pelvis and rib fractures had occurred in 78 (1.6%), 40 (0.8%), 390 (8.1%), 19 (0.4%) and 125 (2.6%) individuals, respectively (subjects may have had more than one main fracture). Subjects who had experienced a main prevalent fracture had lower HRQL scores compared with non-fractured participants. The largest differences were observed in the physical functioning (-4.0; 95% confidence intervals (CI): -6.0, -2.0) and role-physical functioning domains (-5.8; 95% CI: -9.5, -2.2). In women, the physical functioning domain was most influenced by hip (-14.9%; 95% CI: -20.9, -9.0) and pelvis (-18.1; 95% CI: -27.6, -8.6) fractures. In men, the role-physical domain was most affected by hip fractures (-35.7; 95% CI: -60.4, -11.1). Subjects who experienced subclinical vertebral fractures had lower HRQL scores than those without prevalent fractures. In conclusion, HRQL was lower in the physical functioning domain in women and the role-physical domain in men who sustained main fractures at the hip. Subclinical vertebral fractures exerted a moderate effect on HRQL.

Aged↗

Health-related quality of life with coronary heart disease prevention and treatment.

Estimating the net benefits of dyslipidemia treatment is limited by the lack of comprehensive and standardized information on the preference for dyslipidemia and coronary heart disease. In a hospital-based study, we measured the health-related quality of life (HRQOL) of healthy participants without dyslipidemia (n = 307) and with dyslipidemia (n = 251) and patients with coronary heart disease (n = 320). Compared to the healthy participants without dyslipidemia, those with dyslipidemia reported lower adjusted mean scores on the Rating Scale (-2.8 points, P = 0.02) and the SF-36 General Health Scale (-3.3 points, P = 0.02). No differences were observed on the Time Trade-off and the Standard Gamble Scales. Coronary patients reported lower scores on all preference scales and most SF-36 scales. The causes of the small but real reduction in HRQOL reported by dyslipidemic individuals should be identified in order to optimize the net benefits of lipid therapy.

Adult↗