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At least 1,207 records · Page 67Linked to original sources
PubMed2002

Serum CA-125 in preoperative patients at high risk for endometriosis.

OBJECTIVE: To investigate the factors contributing to the elevated level of CA-125 in endometriosis and to study whether CA-125 assay is useful to identify women who require preoperative bowel preparation. METHODS: A total of 685 women undergoing surgery for endometriosis between July 1988 and June 1999 were studied. Preoperative serum CA-125 levels were compared between various pelvic conditions using F statistics. Multiple regression was employed to determine significant correlates of elevated serum CA-125, and the receiver operating characteristic curve was applied to assess the utility of serum CA-125 in preoperative preparation. Based on the two-sample Student t test, the sample size required to detect a difference in mean serum CA-125 levels of one-half of one standard deviation with a power of 90% when the sample size ratio of the two groups was 1:50 was 675 with a significance level of 5%. RESULTS: The mean serum CA-125 levels (IU/mL) for American Society of Reproductive Medicine stages I, II, III, and IV endometriosis were 18.8 +/- 0.9, 40.3 +/- 2.8, 77.1 +/- 3.5, and 182.4 +/- 14.0, respectively. CA-125 levels were significantly increased with advanced stages (P <.001, F test). Furthermore, serum CA-125 levels were significantly higher in patients with more extensive adhesions to the peritoneum, omentum, ovary, fallopian tube, colon, and cul-de-sac, or with ruptured endometrioma (P <.001, F test). We then classified patients with at least one of the three factors including dense omentum adhesion, ruptured endometrioma, and complete cul-de-sac obliteration as the high-risk group that required preoperative bowel preparation, and the others as the low-risk group. Receiver operating characteristic curve analyses set a cutoff point of 65 IU/mL, which gave a sensitivity of 76%, a specificity of 71%, a positive predictive value of 76%, and a negative predictive value of 93.2%. CONCLUSION: Our results suggest that preoperative CA-125 assay is useful to decide which women should receive preoperative bowel preparation. Endometriosis patients with preoperative CA-125 levels higher than 65 IU/mL are at high risk for severe pelvic adhesions that warrant thorough preoperative bowel preparation.

Adult↗
PubMed2001

Effect of addition of Rhodobacter sp. to activated-sludge reactors treating piggery wastewater.

Under aerobic conditions, the decay rates of purple nonsulfur bacteria (Rhodobacter sp.) in the light and dark follow first-order kinetics with rate constants of 0.22 and 0.32 day(-1), respectively. The performance of the conventional activated-sludge reactor (CASR) treating anaerobically pretreated piggery wastewater (656-1.110 mg chemical oxygen demand, COD/L) can be enhanced by the addition of Rhodobacter sp. By performing regressive and statistical analyses using the proposed model and experimental data, the kinetic constants k and Y(T), and the fraction of refractory organic materials (f) of the Rhodobacter sp.-supplemented activated-sludge reactor (RASR) are 40% larger, 21% less, and 34% less than those of the CASR, respectively. From parametric sensitivity analyses, the substrate removal efficiencies of the CASR and RASR are most sensitive to the parameters k and the food to microorganisms ratio (F/M) but least sensitive to the parameter f; the specific oxygen utilization rates of the CASR and RASR are most sensitive to the parameters a and k but least sensitive to the parameter b.

Animals↗
PubMed1997

A lameness scoring system that uses posture and gait to predict dairy cattle reproductive performance.

Lameness has contributed to reproductive inefficiency and increased the risk of culling in dairy cows. We developed a 5-point lameness scoring system that assessed gait and placed a novel emphasis on back posture. Our objective was to determine if this system predicted future reproductive performance and the risk of culling. The study was conducted at a commercial dairy farm with a history of declining reproductive efficiency and an increasing prevalence of lameness. A total of 66 primipara and pluripara calved, received an initial lameness score, and completed their 60-d voluntary waiting period. The overall prevalence of lameness (mean lameness score >2) was 65.2%. Scoring continued at 4-wk intervals and ceased with conception or culling. The percentage of cows confirmed pregnant and culled was 77.3 and 22.7, respectively. For each reproductive endpoint, a 2 x 2 table was constructed with lameness score >2 as the positive risk factor and either performance greater than the endpoint mean or being culled as the positive disease or condition. Positive and negative predictive values, relative risk, Chisquare statistic and regression analysis were used to evaluate the data. The positive predictive values for days to first service, days open, breeding herd days, services per pregnancy and being culled were 58, 68, 65, 39 and 35%, respectively. Similarly, the negative predictive values were 79, 96, 100, 96 and 100%, respectively. Except for one reproductive endpoint, the total number of services, all linear regressions were significant at P < 0.01. Having a lameness score >2 predicted that a cow would have extended intervals from calving to first service and to conception, spend or be assigned to (explained herein) more total days in the breeding herd, require more services per pregnancy and be 8.4 times more likely to be culled. We believe that this lameness scoring system effectively identifies lame cows. Observation of the arched-back posture in a standing cow (> or =LS 3) should trigger corrective interventions.

Journal Article↗
PubMed1989

Association of systemic hypertension and diabetes mellitus with cataract extraction. A case-control study.

The authors conducted a case-control hospital-based study to assess the prevalence of systemic diseases and drugs in 161 cataract extraction patients and 196 surgical patients matched by age, sex, and race. The data were analyzed using matched multiple logistic regressions. A statistically significant increased risk of cataract extraction was found in patients with systemic hypertension (odds ratio [OR] = 1.49, 95% confidence interval [CI] = 1.06-2.09) and diabetes mellitus (OR = 1.79, 95% CI = 1.23-2.60). Estimation of the combined effect of systemic hypertension and diabetes mellitus resulted in an even higher risk for cataract extraction (OR = 2.66, 95% CI = 1.67-4.23). A positive association of cataract extraction and treatment of systemic hypertension with the diuretic furosemide was also found (OR = 1.95, 95% CI = 1.02-3.74).

Aged↗
PubMed2001

Use of interpolated climatic parameters to predict risk of blowfly-strike in Queensland sheep flocks.

The risk of blowfly-strike was investigated in 160 sheep flocks in Queensland, Australia. The association between blowfly-strike--measured by the use of pesticides in response to flystrike reported by flock managers during the period 1994-1997--and interpolated rainfall and temperature data was examined using survival analysis and stepwise regression. The statistical model explaining the most variation in risk of blowfly-strike included average maximum temperature and its second-order polynomial 4 months preceding flystrike. The model was validated using reports of blowfly-strike from 87 flocks during the period 1997-1999 (collected using the same method as for model construction) and interpolated maximum temperature data. Although there was overlap of 95% confidence intervals derived for model coefficients estimated using both construction and validation data sets, false-negative and false-positive misclassification percentages were 33.3 and 53.3%, respectively. False-negative misclassification was greater for flocks located in southern Queensland, and false-positive misclassification was greater for northern Queensland flocks.

Animals↗
PubMed1998

Associations between behavioural indicators of "stress" in weaner pigs and respiratory lesions at slaughter.

The aim of the study was to investigate associations on the individual-pig level between eight behavioural indicators of 'stress' (defined in a very general sense), in seven to eight-week old piglets four weeks after weaning and the occurrence of atrophic rhinitis (AR) and chronic pleuritis (CP) at slaughter. The study was designed as a cohort study, including 512 pigs from two commercial farms. With one exception Actinobacillus pleuropneumoniae serotype 2 (App2) infection was not associated with any of the behaviour patterns observed. Using random-effects logistic regression, weak statistical associations, positive as well as negative, were found between the performance of several behaviour patterns and the two pathological lesions. This suggests the existence of biological associations between oral behaviour patterns in young pigs and the health status later in life. However, the results were not consistent between specific oral behaviour patterns or between the two herds indicating that the associations found are either due to chance or reflect the existence of herd-specific confounders. Therefore, results based on studies within only one herd should not be generalized to other herds without care. Behavioural observations on seven- to eight-week-old piglets on the basis of the present investigation cannot be recommended for use as early predictors of AR or CP at slaughter. Further studies are needed in order to elucidate causal relations between behaviour and health.

Abattoirs↗
PubMed2001

Heel to toe motion characteristics in Parkinson patients during free walking.

OBJECTIVE: Plantar pressures of Parkinson patients in a mild or moderate stage of the disease were analyzed in order to determine characteristics of the heel to toe motion of the foot in Parkinson patients during free walking. DESIGN: Pressure sensitive insoles were used to quantify the in-shoe pressure distribution for 24 patients with Parkinson's disease and for 24 age-matched healthy adults. Peak plantar pressures, relative loads and the variability of relative loads were analyzed for 10 different anatomical foot areas. Inferential statistics and regression analyses were performed to compare subject groups and to relate pressure data to a clinical score (Webster). BACKGROUND: It is well-known that Parkinson patients experience disorders of balance, posture and gait. Recent studies revealed that Parkinson patients show abnormalities in foot strike during walking. However, only little is known about the heel to toe motion of the foot in Parkinson patients in compensating for instability during walking. RESULTS: Parkinson patients show significant changes in foot loading behavior. Parkinson patients have a reduced impact at heel strike. This mechanism was found to be related to the severity of the disease. Furthermore, Parkinson patients show a trend towards higher relative loads in the forefoot regions combined with a load shift towards medial foot areas. These mechanisms are highly stereotypical. CONCLUSION: Parkinson patients, even in a mild or moderate stage of the disease, show significant changes in heel to toe motion of the foot during free walking. The characteristics of Parkinsonian gait are probably caused by adaptive mechanisms of the patients to avoid unsteadiness during walking. RELEVANCE: The results of this study revealed that Parkinson patients have characteristic heel to toe motion pattern. The determination of the foot-loading pattern using plantar pressure measurement may be used as a valuable tool for diagnostic, treatment and rehabilitation purposes. Furthermore, the strategy of the forefoot control in gait of Parkinson patients should be considered in Parkinsonian research.

Analysis of Variance↗
PubMed1998

Context, composition and heterogeneity: using multilevel models in health research.

This paper considers the use of multilevel models in health research. Attention focuses on the structure and potential of such models and particular consideration is given to their use in elucidating the importance of contextual effects in relation to individual level social and demographic factors in understanding health outcomes, health-related behaviour and health service performance. Four graphical typologies are used to outline the questions that multilevel models can address and the paper illustrates their potential by drawing on published examples in a number of different research areas.

Analysis of Variance↗
PubMed1987

Intraocular lens calculation formulas for new intraocular lens implants.

Several different formulas are available for preoperative calculation of the required implant power for a desired postoperative refraction. However, the application of both theoretical and statistically derived regression formulas to the new generation of soft intraocular lens implants poses several difficulties. In this paper the calculation of an A constant for a specific intraocular hydrogel lens implant, as well as the derivation of a universal theoretical formula, is described. The theoretical formula can be applied to other implant styles with various optical configurations and composed of different biomaterials. The SRK and theoretical formulas have been applied retrospectively to a series of patients receiving an intraocular hydrogel lens implant. A comparison shows that both perform satisfactorily in predicting the desired postoperative refraction.

Computer Simulation↗
PubMed2002

QSAR studies on antimalarial substituted phenyl analogues and their N(omega)-oxides.

A quantitative structure--activity relationship (QSAR) study on a series of substituted phenyl analogues 5-[(7-chloro-4-quinolinyl)amino]-3-[(alkylamino)methyl](1,1'-biphenyl)-2-ols and their N(omega)-oxides was made using various combinations of electronic and topological parameters. Several statistically significant regression expressions were obtained using multiple regression analyses. These regressions may be considered as mathematical models for investigating antimalarial activities of the compounds under present study. The antimalarial activity mechanism was investigated using combinations of E(L) and E(H), independently with other molecular descriptors.

Antimalarials↗
PubMed1999

Depressive symptoms and mortality in older Mexican Americans.

PURPOSE: We examined the prevalence of comorbid depressive symptomatology and leading chronic medical conditions, and their influence on death rates in older Mexican Americans. METHODS: Data from the Hispanic Established Population for the Epidemiologic Study of the Elderly (EPESE) were used. Differences in death rates across sociodemographics, self-ratings of health, and health conditions were examined with analysis of variance statistics. Logistic regression models were used to examine main effects and interaction effects of each medical condition separately and in conjunction with depressive symptomatology. RESULTS: Bivariate analyses indicated that death rates were substantially higher when a high level of depressive symptoms was comorbid with diabetes (OR = 3.84, 95% CI = 2.55-5.78), cardiovascular disease (OR = 4.04, 95% CI = 2.36-6.91), hypertension (OR = 2.27, 95% CI = 1.57-3.27), stroke (OR = 3.00, 95% CI = 1.44-6.15), and cancer (OR = 4.46, 95% CI = 2.48-8.01). Multivariate analyses indicated a synergistic effect for comorbid diabetes and depressive symptoms such that the odds of having died among diabetics with high levels of depressive symptoms (OR = 4.03, 95% CI = 2.67-6.11) were three times that of diabetics without high levels of depressive symptoms (OR = 1.36, 95% CI = 0.89-2.06). CONCLUSIONS: High levels of depressive symptoms concomitant with major chronic medical conditions elevate the risk for death among older Mexican Americans. Given the fact that depression is often unrecognized and undertreated in the elderly, awareness of the potential for loss of life as well as the potential for treatment may help to improve this situation not only for older Mexican Americans, but for older adults in general.

Aged↗
PubMed2001

Social cognitive correlates of sexual experience and condom use among 13- through 15-year-old adolescents.

PURPOSE: To examine the role of self-efficacy, outcome expectancies, and perception of peer attitudes in the delay of onset of sexual activity among 13- through 15-year-old adolescents. We also explored the role of self-efficacy, outcome expectancies, and perception of friends' condom use behavior in explaining the use of condoms among sexually active adolescents. METHODS: This study was part of a larger cross-sectional study to evaluate personal characteristics and maternal factors associated with early initiation of sexual intercourse. Mothers and adolescents were recruited from a community-based organization that offered afterschool and summer programs for youth. Enrollment was limited to adolescents aged 13-15 years and their mothers. Mothers and adolescents completed separate interviews. For adolescents, the interviews included the assessment of the variables in the present study. Each interview lasted about 60 min and was conducted by a trained interviewer. Data were analyzed using descriptive statistics and regression analysis. The average age of the 405 adolescent participants was 13.86 years, and approximately 30% of them had engaged in sexual intercourse. Slightly more than half (56%) of participants were male, and 82% were African-American. RESULTS: Participants who were less likely to believe that their friends favored intercourse for adolescents and who held more favorable attitudes about the personal benefits of abstaining from sex were less likely to have initiated sexual intercourse. Among sexually active adolescents, those who expressed confidence in putting on a condom, and in being able to refuse sex with a sexual partner, and who expressed more favorable outcome expectancies associated with using a condom were more likely to use condoms consistently. CONCLUSIONS: Human immunodeficiency virus and pregnancy prevention programs should emphasize peer influences in both the initiation of sexual intercourse and the use of safer sex practices among sexually active adolescents, as well as personal attitudes about consequences to self and confidence in negotiating safer sex practices with one's partner.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Poor glycemic control is associated with increased diastolic blood pressure and heart rate in children with Type 1 diabetes.

Although higher levels of hemoglobin A1c (HbA1c) and blood pressure precede the development of nephropathy in Type 1 diabetes (T1DM), the relationship between glycemic control and cardiovascular factors early in the course of diabetes is not clear. We conducted a retrospective study from clinic data for a 1-year period in 148 children with T1DM aged 12.5+/-4.4 years who had average diabetes duration of 4.5+/-3.3 years. The influence of HbA1c and reported insulin dose on blood pressure and heart rate were analyzed in multivariate linear regression models, statistically adjusted for the effect of race, sex, age, body mass index, and duration of diabetes. There was a significant positive correlation of mean HbA1c with mean diastolic blood pressure (P<.025) and mean heart rate (P<.0004). Higher diastolic blood pressure and heart rate were associated with higher HbA1c. Increased insulin doses were also associated with increased diastolic blood pressure (P<.009) and heart rate (P<.013). Insulin dose and HbA1c were also significantly correlated (P<.001). There was no correlation between mean HbA1c and mean systolic blood pressure. Increased levels of HbA1c and insulin dose are associated with increased diastolic blood pressure and heart rate. Although within the normal range, early increases of diastolic blood pressure and heart may indicate early cardiovascular changes in response to diabetes and potentially contribute to a greater proclivity for later development of nephropathy.

Adolescent↗
PubMed2005

Genetic polymorphisms in methylenetetrahydrofolate reductase and thymidylate synthase and risk of pancreatic cancer.

BACKGROUND & AIMS: Human pancreatic cancer might be associated with folate deficiency and impaired metabolism. We tested this hypothesis by examining the contribution of functional polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) to risk of cancer. METHODS: DNA from 163 pancreatic cancer patients and 337 control subjects was genotyped for MTHFR (677C > T and 1298A > C) and TS (5'-untranslated region tandem repeat and G/C). Association with risk of pancreatic cancer was estimated by logistic regression. All statistical tests were two-sided. RESULTS: We observed an increased risk of pancreatic cancer associated with the MTHFR 677CT (odds ratio [OR], 2.60; 95% confidence interval [CI], 1.61-4.29; P = .0005) or 677TT (OR, 5.12; 95% CI, 2.94-9.10; P < .0001) genotype compared with the MTHFR CC genotype. An increased risk of pancreatic cancer was also associated with the TS 3Rc/3Rc genotype (OR, 2.19, 95% CI, 1.13-4.31; P = .022) compared with the TS 3Rg/3Rg genotype. Joint effect between MTHFR C677T polymorphism and smoking or drinking increased risk of pancreatic cancer in a super-multiplicative manner. The ORs for smoking, the polymorphism, and both factors combined were 0.70 (95% CI, 0.30-1.63), 2.17 (95% CI, 1.17-4.21), and 3.10 (95% CI, 1.54-6.51), respectively. This joint effect was much stronger in heavy smokers (OR, 6.69; 95% CI, 3.39-13.63; P < .0001). The ORs for drinking, the polymorphism, and both factors combined were 0.98 (95% CI, 0.40-2.30), 2.81 (95% CI, 1.65-4.98), and 4.39 (95% CI, 2.25-8.78), respectively. CONCLUSION: The MTHFR and TS polymorphisms are genetic determinants for developing pancreatic cancer.

Adult↗