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PubMed1978

[Comparison of regression line analysis for several antibiotics on different media (author's transl)].

The method for performing regression analysis is described in detail. MIC values and zone sizes are determined on agar throughout. Applying these techniques, good correlation between MIC's and zone sizes (r = greater than -0.9) were found with 82% of 59 regressions (33 different antibiotics). Comparable results were found with DST- and Mueller-Hinton agar. In some cases a linear regression for MIC and zone size values could be demonstrated, independent from the correlation coefficient. Some theoretical aspects of regression analysis are discussed.

Anti-Bacterial Agents↗
PubMed2002

Para-aortic lymph node metastasis in relation to serum CA 125 levels and nuclear grade in endometrial carcinoma.

BACKGROUND: To investigate the relationship between preoperative serum CA 125 levels and para-aortic lymph node (PAN) metastasis as determined by systematic pelvic and para-aortic lymph node dissection in endometrial carcinoma. METHODS: This study included 180 patients (n = 55, premenopausal; n = 125, postmenopausal) with endometrial carcinoma treated by complete surgical staging. Cut-off values of preoperative serum CA 125 levels for PAN metastasis were determined by receiver characteristic curve (ROC) analysis. Logistic regression analysis was used to determine independent predictors for PAN metastasis. RESULTS: The median serum CA 125 levels of patients with PAN metastasis were significantly higher than the levels of those with no metastasis in both premenopausal and postmenopausal groups. Based on ROC analysis, we could determine four cut-off values (70 and 210 U/mL for premenopausal patients, 20 and 60 U/mL for postmenopausal patients) and categorize the serum CA 125 levels into low, moderate and high groups. By logistic regression analysis, the CA 125 level and nuclear grade were found to be significant predictors of PAN metastasis, respectively. Using this model, the patients were stratified into three risk groups. The probabilities of PAN metastasis for patients in the low-risk, intermediate-risk and high-risk groups were less than 2%, 2-25% and more than 50%, respectively. CONCLUSIONS: Serum CA 125 levels and nuclear grade are important risk factors for PAN metastasis in endometrial carcinoma.

Adult↗
PubMed1992

Why do elderly people seek professional home care? Methodologies compared.

In order to investigate which characteristics, besides physical limitations, of elderly people living at home contribute to the utilization of professional home care, a study was conducted in which 450 elderly people aged 55 and over, 123 with and 327 without professional home care, were interviewed. To obtain a selection for the interviews, a postal questionnaire, containing questions on functional status and care utilization, sent out to a random sample of the elderly people (55+) living at home (n = 2451), preceded the actual interviews. The oral interviews yielded the same information, plus an inventory of aspects of the mental status, the social network, the socio-economic status and the housing condition. Analysis was performed in three ways: bivariate analysis, logistic regression analysis and discriminant analysis. The bivariate analysis revealed that users of professional care were older, more often female and more often not married. Their social network was less extensive, as they received less informal care and lived alone more often. Besides they had more mental and financial problems. From the regression analysis it appeared that, in addition to the functional status, the amount of informal care and the household composition contributed to the utilization of professional home care. For the other characteristics inventoried, no independent association with the utilization of professional care could be established. With hindsight, it appeared that in this study long interviews hardly had additional value over postal questionnaires, in which the contribution of functional status and informal care to professional care was already discovered.

Aged↗
PubMed2003

Assessing the effect of Taiwan's outpatient prescription drug copayment policy in the elderly.

OBJECTIVES: This study uses variance cost analysis and regression analysis as tools for investigating the initial effects of Taiwan's outpatient prescription drug copayment program in the elderly. Under its new National Health Insurance program, Taiwan implemented a prescription drug cost-sharing program August 1, 1999. We compare an elderly population's prescription drug use after the policy was implemented with an elderly population's prescription drug use before the policy change to describe initial and general consequences of the drug cost-sharing program. METHODS: Approximately 240,000 patients aged 65 and over representing 1,600,000 outpatient prescriptions were drawn from 21 hospitals in the Taipei area for the study using a stratified random sampling method. Variance analysis, as used primarily in accounting, was applied to decompose overall cost variance of the policy into the sum of variances of several specific factors that are important to policymakers. The cost variances of each specific factor can be further decomposed into sublevels of analyses. Regression analysis is then applied to better understand covariates that might influence drug cost variances of significant magnitude. RESULTS: The initial effects of the policy change did not reverse the trend of drug cost increases. Instead, there was a significant increase in total prescription drug costs in the cost-sharing group (approximately 12.86%) and an even higher increase rate in the non-cost-sharing group (approximately 51.42%). The main reason for the drug cost increase for the cost-sharing group was attributed to an increase in average drug costs per prescription (explaining 69.20% of the variance). We found physicians seemed to prescribe more expensive drugs and extend prescription duration, especially when drug costs exceed the upper bound of the cost-sharing schedule. By contrast, the main factor contributing to the increase in drug costs for the non-cost-sharing group was an increase in average prescription duration (explaining 64.98% of the variance). The increase mainly results from the effect of extended prescriptions for chronic diseases that were designed to reduce unnecessary visits for refills. DISCUSSION: The significant increase in average drug price per prescription indicates that many prescriptions could move above the upper bound of the cost-sharing schedule. The results suggest that the Bureau of National Health Insurance should increase the upper bound. We do not think these effects are unique to Taiwan. Rather, these effects should be considered as countries change their outpatient drug benefit programs. We also found a decrease in utilization of essential drugs with an increase in utilization of nonessential drugs for patients subject to copayments. The results suggest potential adverse effects on patients' health outcome.

Accreditation↗
PubMedDate not supplied

Predictors of intention to study nursing among school students speaking a language other than English at home.

There is currently a shortage of bilingual nurses in New South Wales. It is important to include bilingual nurses in the workforce to meet not only the cultural and social needs of people speaking a language other than English at home, but also to facilitate the achievement of appropriate health outcomes for a multicultural population. The purpose of this study was to identify demographic and social factors which explain students' intention to study nursing. Respondents were 789 year 11 or 12 students speaking Arabic, Serbo-Croatian, Spanish, Turkish or Vietnamese from twenty-five schools in South Eastern, South Western and Western Sydney. Data were collected through a self-completed questionnaire. Chi square, t-test and logistic regression analysis were used for data analysis. Logistic regression analysis concluded that perceived parental income, years of settlement in Australia and father's occupation were significant factors. Bivariate analysis also revealed that significant differences were found in the intention to study nursing between male and female students and between students with a higher and lower Tertiary Entrance Rank (TER). Parental influence also affects students' intention. However, gender and TER were found to be insignificant after adjustment for other variables in the logistic regression model.

Adolescent↗
PubMed2003

Neonates born to pre-eclamptic mothers have a higher percentage of natural killer cells (CD3-/CD56+16+) in umbilical cord blood than those without pre-eclampsia.

OBJECTIVE: Maternal endothelial dysfunction and intravascular inflammation have been implicated in the mechanisms of disease responsible for the clinical syndrome of pre-eclampsia. Recently, the activation of the innate limb of the immune response (neutrophils and monocytes) in the fetal circulation has been reported in neonates born to mothers with pre-eclampsia. Natural killer (NK) cells are identified morphologically as a subpopulation of lymphocytes, but functionally as one component of the innate immune system. NK cells participate in the control of viral or bacterial infection, regulation of hematopoiesis, production of cytokines and cytotoxicity of neoplastic cells. Accumulating evidence suggests that the innate system is required for mounting an adequate adaptive response. NK cells, originally defined as effector cells of the innate immune system, may also play a role as regulatory cells for the adaptive immune system. This study was designed to determine the proportion of the NK cell subset of lymphocytes in umbilical cord blood of neonates born to mothers with and without pre-eclampsia. METHODS: A cross-sectional study including neonates of mothers with (n = 48) and those without pre-eclampsia (control group) (n = 72) was conducted. Pre-eclampsia was diagnosed in the presence of hypertension and proteinuria. The control group consisted of neonates (premature and term) with no evidence of acute inflammation within the extraplacental membranes (chorioamnionitis). Umbilical cord blood was collected at the time of delivery, and assayed using monoclonal antibodies for selective cluster differentiation (CD) antigens in order to determine the proportion of NK cells as a percentage of total lymphocytes. The immunophenotypic characteristic was determined using flow cytometry, and NK cells were identified by positivity of CD16 and CD56 without CD3 (CD3-/CD56+16+). Log transformation of the percentage of NK cells was performed. Parametric statistics were used for analysis. Multiple regression analysis was utilized to examine the contribution of potentially confounding factors on the proportion of NK cells. A p value of < 0.05 was considered statistically significant. RESULTS: Neonates born to mothers with pre-eclampsia had a significantly higher percentage of NK cells (CD3-/CD56+16+) than those in the control group (pre-eclampsia, mean +/- SD 17 +/- 9% vs. control, mean +/- SD 12 +/- 7.5%; p = 0.001). Multiple regression analysis suggested that umbilical cord blood pH of < 7.2, labor with vaginal delivery and maternal pre-eclampsia were associated with an increased percentage of NK cells in umbilical cord blood. CONCLUSIONS: Pre-eclampsia is associated with a higher NK cell (CD3-/CD56+16+) subset of lymphocytes in umbilical cord blood than in the control group. This difference cannot be explained by fetal acidosis or the presence of labor.

CD3 Complex↗
PubMed2006

Preoperative predictive factors for hearing preservation in vestibular schwannoma surgery.

OBJECTIVES: We performed a retrospective chart review to evaluate the various predictive factors for postoperative hearing preservation in the surgical management of vestibular schwannoma. METHODS: Of 792 patients operated on for vestibular schwannoma between April 1987 and July 2002, 107 were candidates for hearing preservation surgery. These patients were divided into group 1 (hearing preserved) and group 2 (hearing not preserved), and both of these groups were evaluated for age, sex, pure tone average, sound discrimination score, tumor size, and auditory brain stem response parameters. A corrected chi2 test and a corrected t-test were used for statistical analysis. Multiple regression analysis was further done to evaluate independent predictive factors, either alone or in combination. The results were evaluated by use of the modified Sanna classification and the guidelines of the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS). RESULTS: Preoperative pure tone average and tumor size were the 2 predictive factors in our study. A Pearson correlation test showed that there was no multicollinearity between the factors. On multiple regression analysis by backward elimination of nonsignificant factors, we found that tumor size is an independent predictive factor for postoperative hearing. According to the modified Sanna classification, postoperative hearing was preserved in 11.2% of patients (equivalent to class A of AAO-HNS guidelines). CONCLUSIONS: In our series, preoperative pure tone average and tumor size were found to be predictors of postoperative hearing levels.

Adolescent↗
PubMed2002

High-grade dysplasia and invasive carcinoma in colorectal adenomas: a multivariate analysis of the impact of adenoma and patient characteristics.

BACKGROUND AND AIMS: Most colorectal carcinomas develop from preformed adenomas, but only a minority of adenomas undergo malignant transformation. The clinical significance of polyps of size < 0.5 cm is controversial. The primary goal of this study was to assess the independent risk factors of adenoma and patient characteristics associated with advanced pathological features (APF; i.e. high-grade dysplasia or invasive carcinoma) in colorectal adenomas. A secondary goal was to assess the malignant potential of adenomas with a diameter of < 0.5 cm. PATIENTS AND METHODS: Patients who underwent total colonoscopy at our Medical Department between 1978 and 1996 and had at least one colorectal adenoma were considered for this study. Patients with a history of colorectal cancer, prior polypectomy or colorectal surgery were excluded. A total of 7590 adenomas removed from 4216 patients were included in this analysis. Logistic regression analysis was used to study the impact of different adenoma and patient characteristics on the risk of APF. RESULTS: Size proved to be the most important risk factor for APF. The percentage of adenomas with APF was 3.4%, 13.5% and 38.5% for adenomas of diameter < 0.5 cm, 0.5-1 cm and > 1 cm, respectively. Villous or tubulovillous histology, left-sided location and age >or= 60 years were also associated with APF, whereas sex and number of adenomas had no significant impact. Logistic regression analysis revealed that the risk of an adenoma containing APF was best described by a model incorporating the factors size, location, age, and the age by histology interaction. In the class of adenomas with diameter < 0.5 cm, no invasive carcinoma was found, but 3.4% of adenomas had high-grade dysplasia. CONCLUSIONS: The risk of a colorectal adenoma containing APF can be estimated only by a complex model taking into account several adenoma and patient characteristics. Size, histological type, location and age are independent risk factors for APF in colorectal adenomas. As a considerable percentage of adenomas with diameter < 0.5 cm contain high-grade dysplasia, the clinical conclusion from our study is that all adenomas, including those with diameter < 0.5 cm, should be removed whenever possible.

Adenoma↗
PubMed1997

Popliteal artery trauma. Systemic anticoagulation and intraoperative thrombolysis improves limb salvage.

OBJECTIVE: This study was conducted to evaluate those factors associated with popliteal artery injury that influence amputation, with emphasis placed on those that the surgeon can control. SUMMARY BACKGROUND DATA: Generally accepted factors impacting amputation after popliteal artery injury include blunt trauma, prolonged ischemic times, musculoskeletal injuries, and venous disruption. Amputation ultimately results from microvascular thrombosis and subsequent tissue necrosis, predisposed by the paucity of collaterals around the knee. METHODS: Patients with popliteal artery injuries over the 10-year period ending November 1995 were identified from the trauma registry. Preoperative (demographics, mechanism and severity of injury, vascular examination, ischemic times) and operative (methods of arterial repair, venous repair-ligation, anticoagulation-thrombolytic therapy, fasciotomy) variables were studied. Severity of extremity injury was quantitated by the Mangled Extremity Severity Score (MESS). Amputations were classified as primary (no attempt at vascular repair) or secondary (after vascular repair). After univariate analysis, logistic regression analysis was performed to identify the independent risk factors for limb loss. RESULTS: One hundred two patients were identified; 88 (86%) were males and 14 (14%) were females. Forty injuries resulted from blunt and 62 from penetrating trauma. There were 25 amputations (25%; 11 primary and 14 secondary). Patients with totally ischemic extremities (no palpable or Doppler pulse) more likely were to be amputated (31% vs. 13%; p < 0.04). All requiring primary amputations had severe soft tissue injury and three had posterior tibial nerve transection; the average MESS was 7.6. Logistic regression analysis identified independent factors associated with secondary amputation: blunt injury (p = 0.06), vein injury (p = 0.06), MESS (p = 0.0001), heparin-urokinase therapy (p = 0.05). There were no complications with either heparin or urokinase. CONCLUSIONS: Minimizing ischemia is an important factor in maximizing limb salvage. Severity of limb injury, as measured by the MESS, is highly predictive of amputation. Intraoperative use of systemic heparin or local urokinase or both was the only directly controllable factor associated with limb salvage. The authors recommend the use of these agents to maximize limb salvage in association with repair of popliteal artery injuries.

Adolescent↗
PubMedDate not supplied

Crohn's disease in rheumatology clinic--an Indian experience.

BACKGROUND: Prevalence of Crohn's disease (CD) among patients with rheumatic illnesses in India is grossly under estimated, especially when it has overtaken that of Ulcerative Colitis in the West. AIM: To study the frequency of histologically unequivocal CD amongst clinically suspected patients with enteropathic arthropathy and to ascertain if the arthritics with CD have any independent clinical predictor. SETTINGS AND DESIGNS: Retrospective datasheet analysis from a Rheumatology clinic of a large tertiary care centre. MATERIALS AND METHODS: Patients of suspected enteropathic arthropathy were studied by ileocolonoscopy and segmental colonic biopsy for histological evidence of Crohn's disease and followed up. STATISTICAL ANALYSIS: Logistic regression analysis was done to find out any clinical predictor of histologically proven CD. RESULTS: Fourteen of the twenty-nine patients studied had histologically confirmed CD. Those with CD were younger than those without (34.7 yr vs 41.6 yrs, p=0.057). The CD group also had significantly higher number of people with loss of weight (12 vs 1), fever (11 vs 0), perianal fistula (4 vs 0), abdominal pain (8 vs 2), history of dysentery (4 vs 0) and uveitis (6 vs 1) (p=0.00002, 0.00001, 0.026, 0.013, 0.026 & 0.01 respectively). However logistic regression analysis of the most relevant ones among these, namely, loss of weight, fever, and perianal fistula showed loss of weight as only independent predictor of CD in this subset of patients (p=0.03 with odds ratio of 28). CONCLUSION: Presence of significant loss of weight in an Indian patient with clinically suspected enteropathic arthropathy is an independent predictor of CD.

Adult↗
PubMed1989

[Analysis of conditional logistic regression for risk factors of lung cancer in Dachang Tin Mine].

An increased risk of lung cancer in Dachang Tin Mine of Guangxi has been reported. To investigate the factors of the excessive risk of lung cancer, the authors conducted a matched pair case-control study in the mine area and analysed the effect of multiple factors, such as condition of living and housing, occupational exposure and smoking by statistical method of conditional logistic regression. The patients group consisted of 69 patients with primary bronchogenic cancer including 55 deceased. The control group consisted of 138 persons also including 55 deceased. The results showed that the factors of the excessive risk of lung cancer in the mine area were mainly related to the occupational exposure. The risk factors with statistical significance in conditional logistic regression analysis were exposure time of smelting, time of underground drilling, and age of beginning mining underground. In the study model of all cases matched against living controls, daily number of cigarette also was a risk factor besides the above three factors. Furthermore, there was a synergic action among the factors. The relationship between the risk factors and lung cancer is discussed.

Humans↗
PubMed2003

Role of Fcgamma receptors IIA, IIIA, and IIIB in susceptibility to rheumatoid arthritis.

OBJECTIVE: To investigate the role of Fcg receptor (FcgR) genes in susceptibility to rheumatoid arthritis (RA) using family based studies, to examine possible interactions between FcgR genotypes and the shared epitope (SE), and to assess linkage disequilibrium between FcgR loci. METHODS: Association studies were performed in 95 Caucasian, single-case, nuclear Caucasian families with both parents alive using haplotype based haplotype relative risk (HHRR) and transmission disequilibrium test (TDT) statistics. Three FcgR polymorphisms (FcgRIIA-131H/R, FcgRIIIA-158V/F, and FcgRIIIB-NA1/NA2) were genotyped using polymerase chain reaction methods. Linkage analysis was performed using 3 microsatellite markers (D1S498, D1S2844, D1S2762) flanking the FcgR region in an independent set of 90 Caucasian, multiple-case families. Potential effects of disease heterogeneity, including sex and the presence of rheumatoid factor, SE, and erosive or nodular disease, were taken into account in the analysis. Logistic regression analysis was performed to determine whether FcgR alleles are independent risk factors for the susceptibility to and/or severity of RA. Linkage disequilibrium was calculated using pairwise linkage disequilibrium statistics. RESULTS: HHRR and TDT analysis showed no evidence of preferential transmission of any FcgR alleles studied, and there were no important associations with any given disease phenotype. Moreover, neither linkage to microsatellite markers close to the FcgR genes on chromosome 1 nor linkage disequilibrium between FcgR loci was present in our population. The distribution of inherited genotypes provided evidence for an interaction between the SE and the FcgRIIIA-158V allele and between the SE and the FcgRIIIA-158V-FcgRIIA-131H 2-locus haplotype since the combined presence of these factors increased the susceptibility to RA (OR 4.13, 95% CI 1.6-10.62 and OR 2.83, 95% CI 1.25-6.38, respectively). However, regression analysis showed that neither the 158V allele nor the 158V-131H haplotype contributed as independent factors to susceptibility or severity of RA. CONCLUSION: Isolated FcgR genes do not play a major independent role in susceptibility to RA. To a limited extent, the presence of high-binding alleles at the FcgRIIIA locus or at the FcgRIIIA-FcgRIIA haplotype might predispose to RA in SE positive individuals.

Adolescent↗
PubMed2005

In-house nucleic acid amplification tests for the detection of Mycobacterium tuberculosis in sputum specimens: meta-analysis and meta-regression.

BACKGROUND: More than 200 studies related to nucleic acid amplification (NAA) tests to detect Mycobacterium tuberculosis directly from clinical specimens have appeared in the world literature since this technology was first introduced. NAA tests come as either commercial kits or as tests designed by the reporting investigators themselves (in-house tests). In-house tests vary widely in their accuracy, and factors that contribute to heterogeneity in test accuracy are not well characterized. Here, we used meta-analytical methods, including meta-regression, to identify factors related to study design and assay protocols that affect test accuracy in order to identify those factors associated with high estimates of accuracy. RESULTS: By searching multiple databases and sources, we identified 2520 potentially relevant citations, and analyzed 84 separate studies from 65 publications that dealt with in-house NAA tests to detect M. tuberculosis in sputum samples. Sources of heterogeneity in test accuracy estimates were determined by subgroup and meta-regression analyses. Among 84 studies analyzed, the sensitivity and specificity estimates varied widely; sensitivity varied from 9.4% to 100%, and specificity estimates ranged from 5.6% to 100%. In the meta-regression analysis, the use of IS6110 as a target, and the use of nested PCR methods appeared to be significantly associated with higher diagnostic accuracy. CONCLUSION: Estimates of accuracy of in-house NAA tests for tuberculosis are highly heterogeneous. The use of IS6110 as an amplification target, and the use of nested PCR methods appeared to be associated with higher diagnostic accuracy. However, the substantial heterogeneity in both sensitivity and specificity of the in-house NAA tests rendered clinically useful estimates of test accuracy difficult. Future development of NAA-based tests to detect M. tuberculosis from sputum specimens should take into consideration these findings in improving accuracy of in-house NAA tests.

Gene Amplification↗
PubMed1994

Genetic analysis combining path analysis with regressive models: the BETA path model of polygenic and familial environmental transmission.

We have extended the class D regressive model for the purpose of combined path and segregation analyses by incorporating the BETA path model. We have done this by expressing correlations among residuals from major genotype (RMGs) of family members under the class D regressive model as functions of path coefficients under the BETA path model. The likelihood function under the combined model was factorized into a product of conditional densities, which is dominated by bivariate normal densities. Statistical inferences under the combined model are analogous to those under the class D regressive model.

Binomial Distribution↗
PubMed2002

Sex differences in QTc interval and QT dispersion: dynamics during exercise and recovery in healthy subjects.

BACKGROUND: Sex differences have been described in resting cardiac repolarization and susceptibility to torsade de pointes in humans. This study compares the QT-interval and QT-dispersion dynamics during exercise and recovery between healthy men and women. METHODS: Twenty healthy subjects (10 males aged 30 +/- 4 years, 10 females aged 31 +/- 11 years) underwent symptom-limited bicycle ergometry followed by a 10-minute recovery period. Digital 12-lead electrocardiograms (ECG) were recorded every 10 seconds during exercise and recovery. For each lead, the QTp interval (Q onset to T peak) was automatically measured by use of QT Guard (GE Marquette, Milwaukee, Wis). QTp dispersion was defined as the difference between the maximum and minimum QTp for each ECG. To quantify QT dynamics, we fit the QTp in lead V(3) (QTpV(3)) versus cycle length (CL) relationship to a quadratic function during exercise and recovery with nonlinear regression analysis. Similar regression analysis was performed for the QTp dispersion versus CL relationship. RESULTS: At baseline, QTpcV(3) was longer in women than in men (338 +/- 25 vs 278 +/- 15 ms, P <.0001), but QTp dispersion was similar (35 +/- 18 vs 41 +/- 19 ms). At peak exercise, QT dispersion decreased compared with baseline in both men and women. During exercise and recovery, women had a steeper QTpV(3)-CL relationship. QTpV(3) hysteresis, a measure of the exercise and recovery QTpV(3)-CL curve separation, was greater in women than in men when measured 1 minute into recovery (33 +/- 20 vs 6 +/- 8 ms, P <.001). No sex difference in QTp-dispersion-rate adaptation was observed during exercise or recovery. CONCLUSIONS: Healthy women exhibit greater QT-interval-rate adaptation during both exercise and recovery than men, resulting in more QT-interval hysteresis. Greater QT prolongation during decelerating heart rates in recovery may play a role in increasing proarrhythmia risk in women.

Adult↗
PubMed2006

Evolutionary history of HIV-1 subtype B and F infections in Brazil.

OBJECTIVE: To reconstruct the onset date of the HIV-1 B and F epidemics in Brazil based on virus diversification over time. DESIGN: We studied HIV-1 env V3 sequences (210 nt) with a known sampling year isolated from HIV-1 positive patients from Brazil between 1989 and 1997: 101 subtype B sequences and 41 subtype F sequences. METHODS: HIV-1 V3 env sequences were grouped by year of collection and the relationship between the sampling years of HIV-1 sequences and their genetic distance to the reconstructed common ancestor (intra-population divergence) or to other sequences from the same year (intra-population diversity) was examined by using linear regression analysis. RESULTS: Regression analysis of nucleotide distances, revealed a highly significant positive correlation between sampling years of subtype B and F V3 sequences and their intra-population divergence (P < 0.001) or diversity (P < 0.0001). In both subtype populations, the divergence and diversity increased at a rate of 0.5 and 0.9% per year, respectively. Considering these evolutionary rates, we estimate the onset of the subtype B and F HIV-1 epidemics in Brazil during early 1970s and early 1980s, respectively. CONCLUSIONS: The consistent correlation between divergence and diversity of the V3 sequences with their sampling years indicates that the molecular clock is operational in the evolution of the HIV-1 in Brazil's epidemic, and show that subtypes B and F are evolving at a similar rate over time. The dating results suggest a discontinuous introduction of these subtypes in the Brazilian population.

Brazil↗
PubMed2001

Waist to hip circumference ratio as a significant predictor of preeclampsia, irrespective of overall adiposity.

OBJECTIVE: To investigate whether abnormal body fat distribution is a significant predictor of the development of preeclampsia, irrespective of overall adiposity. METHODS: Twenty-six women with preeclampsia and 198 control women were enrolled. Waist to hip circumference ratio (WHR), body weight (BW), and body mass index (BMI, wt/ht2) were measured early in pregnancy (< 9 weeks of gestational age). Age, height, parity, tobacco usage, education period, gestational duration, and weight gain during pregnancy were also recorded for each subject. RESULTS: WHR, BMI, and BW early in pregnancy were significantly higher in the preeclampsia group (p < 0.0001). WHR, BMI, and BW positively correlated with the development of preeclampsia on univariate regression analysis (Standardized regression coefficient = 0.410, 0.387, and 0.363, respectively, p < 0.0001). On stepwise multiple regression analysis, WHR still correlated with the development of preeclampsia irrespective of BMI and BW. When the WHR predictive of the development of preeclampsia was set at 0.9, the sensitivity was 46.2% (12/26), which was significantly better than that of 25 of BMI (19.2%, 5/26; p < 0.05). CONCLUSION: Higher WHR is a significant predictor of the development of preeclampsia. This relation is irrespective of overall adiposity.

Adipose Tissue↗