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At least 1,135 records · Page 63Linked to original sources
PubMed2007

Time trends of mortality after first hip fractures.

UNLABELLED: A register-based study including 2,674 first hip fracture patients from 1987-1996 investigated if the mortality after hip fracture was associated with time trend and fracture type. Despite significantly increasing age at admission no changing time trend of mortality was observed, nor was the mortality linked to the kind of fracture suffered. INTRODUCTION AND HYPOTHESIS: A retrospective cohort study was performed to investigate if the mortality of first hip fracture patients was associated with time trend and fracture type. The hypotheses were that cumulative mortality would remain unchanged and there would be no difference in mortality between cervical and pertrochanteric patients. METHODS: Study material was obtained by record linkage of excerpts from two computerized national health registers. First hip fractures were identified indirectly by searching the files ten years before the date of admission. The period 1987-1996 saw inclusion of 2,674 patients aged 50 years and older (average follow-up 2.6 years). STATISTICS: Weighted regression analysis, chi(2) test, and t test. RESULTS: Cumulative mortality did not change significantly (P > 0.05). Weighted average cumulative mortality was 9% (95% CI, 7.9-10.1) at 1 month, 15.5% (95% CI, 14.1-16.8) at 3 months, 26.5% (95% CI, 24.7-28.3) at 1 year, and 36.2% (95% CI, 34.1-38.3) at 2 years. Cervical and pertrochanteric first hip fracture patients did not have significantly different mortality rates (P > 0.05). CONCLUSION: No changing time trend of mortality after first hip fracture was observed despite significantly increasing age at admission, nor was the mortality linked to the kind of fracture suffered.

Age Distribution↗
PubMed2001

Development of a kinematic coordination pattern in toddler locomotion: planar covariation.

The purpose of this study is to analyze the coordination patterns of the elevation angles of lower limb segments following the onset of unsupported walking in children and to look for the existence of a planar covariation rule as previously described in adult human locomotion. The kinematic patterns of locomotion were recorded in 21 children (11-144 months of age) and 19 adults. In 4 children we monitored the very first unsupported steps. The extent to which the covariation of thigh, shank, and foot angles was constrained on a plane in 3D space was assessed by means of orthogonal regression and statistically quantified by means of principal component analysis. The orientation of the covariation plane of the children was compared with the mean value of the adults' plane. Trunk stability with respect to the vertical was assessed in both the frontal (roll) and sagittal (pitch) planes. The evolution with walking experience of the plane orientation and trunk oscillations demonstrated biexponential profiles with a relatively fast time constant (< 6 months after the onset of unsupported locomotion) followed by a much slower progression toward adult values. The initial fast changes of these walking parameters did not parallel the slow, monotonic maturation of anthropometric parameters. The early emergence of the covariation plane orientation and its correlation with trunk vertical stability reflect the dynamic integration of postural equilibrium and forward propulsion in a gravity-centered frame. The results support the view that the planar covariation reflects a coordinated, centrally controlled behavior, in addition to biomechanical constraints. The refinement of the planar covariation while morphological variables drastically change as the child grows implies a continuous update of the neural command.

Aging↗
PubMed2004

Factors of importance for scintigraphic non-visualisation of sentinel nodes in breast cancer.

PURPOSE: The aim of this study was to analyse different factors of possible significance for non-visualisation of sentinel nodes (SNs) by preoperative lymphoscintigraphy, in order to enable improvement of the success rate of SN visualisation through modification or alteration of some of the factors. METHODS: Between March 1998 and January 2003 we analysed a series of 442 women with unilateral stage T1 and clinical N0 breast cancer. Lymphoscintigraphy was performed after periareolar or peritumoural injection of 99mTc-albumin nanocolloid, with image acquisition after 2-6 h or 18-24 h. Until January 2001, all patients received around 20 MBq tracer, irrespective of time to operation. From January 2001, patients injected on the day before surgery received at least 100 MBq while patients injected on the day of surgery received around 50 MBq. RESULTS: An SN was visualised in 87% of the patients, and at surgery the SN was detected with the hand-held gamma probe in 42% of the remaining patients. By multiple logistic regression analysis, statistically significant independent variables that increased the risk for non-visualisation were increasing age (p=0.0007), increasing body weight (p=0.0189) and peritumoural injection (p<0.0001). Significant interaction was found for imaging time and injected activity (p=0.0017). CONCLUSION: This study conclusively shows that the risk of unsuccessful SN imaging increases with age and body weight. Our findings suggest that the scintigraphic success rate may be improved by periareolar (rather than peritumoural) injection. Early and late imaging procedures are equally efficient, but if a late imaging procedure is used, activity (adjusted for physical decay) in the patient on day 2 should be more than 10 MBq.

Adult↗
PubMed2002

Malformations in newborn: results based on 30,940 infants and fetuses from the Mainz congenital birth defect monitoring system (1990-1998).

Prevalence rates of birth defects in the Federal Republic of Germany are informative to assess the general background risk of having a child with a birth defect. They provide basic figures to determine temporal and regional prevalence trends, to evaluate and initiate preventive measures and to initiate research projects. To avoid observer, definition and collection bias, active monitoring systems are required. Data collected in the active monitoring system of the Mainz Birth Defects Registry are presented. From 1990-1998, 30,940 live-births, stillbirths and abortions underwent standardized physical and sonographic examinations. Anamnestic data were collected from prenatal care records, maternity files and hospital records. Major malformations were diagnosed in 2144 (6.9%) and mild errors of morphogenesis in 11,104 (35.8%) of all infants. Risk factors associated with the occurrence of major malformations were identified by comparing anamnestic data from infants with and without major malformations. Using multivariate regression models, statistically significant associations were established for 9 risk factors. Causally related risk factors were parents or siblings with malformations, parental consanguinity, more than 3 minor errors of morphogenesis in the proband, maternal diabetes mellitus and ingestion of antiallergic drugs in the first trimester of pregnancy. Conjunctional risk factors were polyhydramnios, oligohydramnios and gestational age <32 weeks at birth. Using these risk factors, populations at risk for the occurrence of major malformation can be identified.

Cohort Studies↗
PubMed2005

Influence of a low-level contractile response from the soleus, gastrocnemius and tibialis anterior muscles on viscoelastic stress-relaxation of aged human calf muscle-tendon units.

Measuring viscoelastic stress-relaxation (VSR) as the decline in passive tension over time when the skeletal muscle-tendon unit (MTU) is held in a lengthened position may be difficult in older people who may have difficulty relaxing. This study examined the VSR of the aged calf MTUs with a low-level involuntary contractile response from the soleus (S), gastrocnemius (G) and tibialis anterior (TA) muscles. Calf MTUs of 29 men and women (65-90 years) were stretched to maximal dorsiflexion and held for 60 s while torque (Nm) and surface electromyograms (SEMG) were recorded. Subjects with normalized SEMG (% of maximal voluntary contraction SEMG) of the S, G or TA <1% were assigned to Group 1 (n=14) and subjects with SEMG of the S or G > or =1% and <10%, or in the TA > or =1% were assigned to Group 2 (n=15). Although the mean total percent torque decline for Group 1 (17.9%) and Group 2 (16.6%) did not differ statistically, multiple regression analysis within Group 2 indicated that the G and TA SEMG accounted for 58% of its variation (R (2)=0.581). The G SEMG from 0-15 s accounted for 56% (r (2)=0.563) of the variation in the percent decline normalized to total percent decline (100%). From 15-30 s Group 2 had less percent decline (2%) than Group 1 (14%) (P=0.043) and the S and G SEMG accounted for 67% of its variation (R (2)=0.673). The results indicated that a low-level involuntary contractile response from the S, G and TA muscles may be related to the VSR process of aged calf MTUs. Measuring VSR within time intervals normalized to the total percent decline offers a new method to study VSR, which should be measured with SEMG in the muscles <1% MVC SEMG to ensure valid measurements.

Aged↗
PubMed2007

Insular carcinomas of the thyroid exhibit poor prognosis and long-term survival in comparison to follicular and papillary T4 carcinomas.

BACKGROUND: Insular thyroid carcinoma was described as a tumor with aggressive behavior, and patients usually present themselves with an advanced tumor stage. Whether the insular component is an independent factor for poor prognosis remains unclear. Therefore, in the present study, we compared the survival of patients with advanced insular, follicular, and papillary thyroid cancer. MATERIALS AND METHODS: The clinical behavior of tumors in three groups of patients with T4 thyroid carcinoma--8 patients with insular, 11 patients with follicular, and 21 patients with papillary thyroid carcinomas--was compared. Disease-free survival and disease-specific death were analyzed statistically. Cox regression analysis was used to evaluate the influence of histotype and other prognostic factors. RESULTS: At 3 years, survival was 37.5% (mean 26 months) among patients with insular thyroid carcinoma, 80% (mean 59 months) among those with follicular, and 89% (mean 126 months) among those with papillary thyroid carcinomas (p = 0.007). Disease-free survival in patients without initial distant metastasis was worst in patients with insular thyroid carcinoma (20%) compared to those with follicular (75%) and those with papillary thyroid carcinomas (71%). CONCLUSION: Patients with advanced insular thyroid carcinoma have a poorer outcome in comparison to patients with similar advanced stage who have follicular or papillary thyroid carcinoma.

Adenocarcinoma, Follicular↗
PubMed2001

The glutathione-related detoxification system is increased in human breast cancer in correlation with clinical and histopathological features.

PURPOSE: The glutathione detoxification pathway includes glutathione S-transferase (GST) and peroxidase (GPX) isoenzymes as well as glutathione reductase (GSSR). Though well established from cultured cancer cell lines, its involvement in resistance is still unclear in the tumours. This study aimed to describe the parameters that influence the glutathione contents and associated activities in breast cancer. METHODS: The components of the glutathione pathway were measured in the tumours from 41 women with primary breast cancer in comparison with those in the matched tumour-free samples. Appropriate statistical studies (regression analysis, Wilcoxon signed rank test) explored the influence of clinical and prognostic factors. RESULTS: Reduced and total glutathione contents were largely increased (P < 0.0001) and all related activities were significantly enhanced in the tumours. Interindividual variations were described, probably due to various parameters (age, menopause, axillary lymph node status, S and G2 + M cell fractions, ER, cathepsin-D and c-ErbB-2 expressions) that influence particular components of the glutathione pathway, especially the glutathione levels. CONCLUSIONS: The breast tumours improved their redox status and detoxification capacities depending on various parameters of significance for cell proliferation and aggressiveness, which supports the involvement of the glutathione pathway in malignant cell resistance to oxidative stress and apoptosis.

Adult↗
PubMed2006

The effect of irradiance, vertical mixing and temperature on spring phytoplankton dynamics under climate change: long-term observations and model analysis.

Spring algal development in deep temperate lakes is thought to be strongly influenced by surface irradiance, vertical mixing and temperature, all of which are expected to be altered by climate change. Based on long-term data from Lake Constance, we investigated the individual and combined effects of these variables on algal dynamics using descriptive statistics, multiple regression models and a process-oriented dynamic simulation model. The latter considered edible and less-edible algae and was forced by observed or anticipated irradiance, temperature and vertical mixing intensity. Unexpectedly, irradiance often dominated algal net growth rather than vertical mixing for the following reason: algal dynamics depended on algal net losses from the euphotic layer to larger depth due to vertical mixing. These losses strongly depended on the vertical algal gradient which, in turn, was determined by the mixing intensity during the previous days, thereby introducing a memory effect. This observation implied that during intense mixing that had already reduced the vertical algal gradient, net losses due to mixing were small. Consequently, even in deep Lake Constance, the reduction in primary production due to low light was often more influential than the net losses due to mixing. In the regression model, the dynamics of small, fast-growing algae was best explained by vertical mixing intensity and global irradiance, whereas those of larger algae were best explained by their biomass 1 week earlier. The simulation model additionally revealed that even in late winter grazing may represent an important loss factor during calm periods when losses due to mixing are small. The importance of losses by mixing and grazing changed rapidly as it depended on the variable mixing intensity. Higher temperature, lower global irradiance and enhanced mixing generated lower algal biomass and primary production in the dynamic simulation model. This suggests that potential consequences of climate change may partly counteract each other.

Climate↗
PubMed2001

Anteroposterior weight-bearing radiography of the knee with both knees in semiflexion, using new equipment.

In order to obtain high reproducibility and sensitivity in the evaluation of joint space in osteoarthritic knees, we used new equipment, and established an anteroposterior weight-bearing radiograph with both knees in semiflexion taking into account our investigation of the posterior slope angle. We compared our method with the Rosenberg method, and the coefficient of variation of our method showed higher reproducibility than that of the Rosenberg method. The most essential issue is whether the bilateral leg loading radiograph can show the same sensitivity as the homolateral leg loading radiograph. We compared standing radiographs of the knee in 26 degrees flexion with those of 26 degrees flexion in both knees. We assessed the widths of the narrowest points of the joint spaces in the medial and lateral compartments, the condylar plateau angle, and the femorotibial angle, in 47 knees in 24 patients. The data were analyzed statistically by single regression and each correlation was of statistical significance. Our method has better reproducibility and is more comfortable for the subject than conventional methods.

Humans↗
PubMed2004

A case-control study of occupational risk factors for bladder cancer in Canada.

OBJECTIVE: To investigate occupational risk factors for bladder cancer in seven Canadian provinces. METHODS: We analysed a population-based case-control dataset of 887 individuals with incident, histologically confirmed bladder cancer between 1994 and 1997. Controls (2847) frequency matched for age and gender were surveyed in 1996. Questionnaires were returned by about 60% of subjects. Odds ratios (ORs) for occupations and self-reported exposures were adjusted for province, age, race, smoking, and several dietary factors, using unconditional logistic regression. RESULTS: Statistically significant increased risks were observed among men employed as hairdressers (OR = 3.42; 1.09-10.8), primary metal workers (OR = 2.40; 1.29-4.50), miners (OR = 1.94; 1.18-3.17), and automechanics (OR = 1.69; 1.02-2.82). Primary metal workers and automechanics showed evidence of an employment duration-response trend. Modest elevated risks that were not significant were also observed for male government inspectors, printers, firefighters, general labourers, and welders. A duration-response trend was evident for government inspectors and general labourers. For females, significant elevations were observed among lumber processors (OR = 8.78; 1.28-60.1), general labourers (OR = 2.18; 1.05-4.52), nurses (OR = 1.54; 1.03-2.31), and general clerks (OR = 1.48; 1.01-2.17). The latter showed a positive duration-response trend. CONCLUSIONS: This study found a statistically significant excess risk of bladder cancer, with a duration-response trend, among male primary metal workers and automechanics, and female office workers engaged in general clerical duties.

Adult↗
PubMed1986

Coronary heart disease death, nonfatal acute myocardial infarction and other clinical outcomes in the Multiple Risk Factor Intervention Trial. Multiple Risk Factor Intervention Trial Research Group.

The Multiple Risk Factor Intervention Trial was a randomized clinical study to test whether a special-intervention (SI) program aimed at reducing serum cholesterol levels, blood pressure and cigarette smoking would prevent coronary heart disease (CHD) in middle-aged men. The main endpoint reported here is the percentage of participants experiencing first major CHD events (either nonfatal acute myocardial infarction [AMI] or CHD death) during 7 years of follow-up. This outcome was slightly less frequent in the 6,428 SI men than in the 6,438 men assigned to their usual source of care (UC). However, the relative difference--either 1% (95% confidence interval -17% to 16%) or 8% (95% confidence interval -5% to 20%), depending on how AMI was classified--was not statistically significant. Regression analyses within the SI and UC groups suggested that the cholesterol and cigarette smoking interventions reduced the number of first major CHD events: the associations between lowering the levels of these 2 factors and reductions in CHD rates were significant (p less than 0.001) and of the anticipated magnitude. A similar analysis of antihypertensive treatment in the SI group revealed no favorable association between lowering blood pressure and CHD rate, and other subgroup comparisons suggested that a mixture of beneficial and adverse effects may underlie this finding. Thus, the nonsignificant overall UC/SI contrast in CHD rates may reflect a combination of the expected beneficial effects of the cholesterol and smoking interventions with unexpected heterogeneous effects of the antihypertensive intervention. Seven of 8 other prespecified cardiovascular endpoints occurred less frequently among SI than among UC men, the difference being nominally significant (p less than 0.05) for angina pectoris, congestive heart failure and peripheral arterial disease.

Adult↗
PubMed1990

Comparative studies of 30 micrograms ethinyl estradiol combined with gestodene and desogestrel on blood coagulation, fibrinolysis, and platelets.

An association between an increase in the incidence of thromboembolic disease and the use of combined oral contraceptives has been shown by several epidemiologic studies. Evidence of the vascular complications of oral contraceptives suggests that venous thromboembolism correlates with estrogen dosage and arterial complications with both estrogen and progestogen components. In 60 healthy, randomly allocated women, the effects of ethinyl estradiol, 30 micrograms, combined with gestodene, 75 micrograms, and desogestrel, 150 micrograms, on blood coagulation, fibrinolysis, and platelet function were compared. Subjects were studied before oral contraceptive use, at 12, 24, 36, and 48 weeks of treatment, and at 6 and 12 weeks after treatment. Both oral contraceptives affected the hemostatic system, but our results indicate that the ethinyl estradiol/gestodene combination causes changes in the hemostatic system similar to those in the ethinyl estradiol/desogestrel combination. Factors VII and X activity were slightly higher with the ethinyl estradiol/desogestrel combination than with the ethinyl estradiol/gestodene combination, possibly reflecting a greater estrogenic effect.

Adolescent↗
PubMed1987

Are 'precipitated LDL' really low density lipoproteins?

Cholesterol, phospholipid and Apo B levels were determined in low density lipoproteins (LDL) precipitated by amphipathic polymers (Biomérieux kit, Marcy-l'Etoile, France) and compared to those of ultracentrifuged LDL. For 113 sera (triglyceride level less than 4.5 mmol/l, absence of very low density lipoproteins-remnants) LDL-cholesterol values were significantly higher (p less than 0.001), and those of LDL-phospholipids (p less than 0.001) and LDL-Apo B (p less than 0.005) significantly lower. The correlations between the 3 constituents studied gave statistically different regression coefficients for the two methods. It is likely that discrepancy in results is due to the effect of ultracentrifugation and precipitation removing from the lipoprotein spectrum different sections which nonetheless have some common physicochemical or immunological properties. It would seem that the term 'LDL' is inappropriate to designate these precipitated lipoproteins.

Apolipoproteins B↗
PubMed1989

Acceptability of an experimental intracervical device: results of a study controlling for selection bias.

We analyzed baseline and 12-month follow-up interview data from 98 women who had volunteered to use an experimental intracervical device (ICD) and from 155 women who had been randomly assigned to two control groups, the levonorgestrel-releasing intrauterine device (LNG-IUD; N = 86) and the copper Nova-T IUD (N = 69). All participants were clinic patients in Helsinki, Finland. Initial analysis of 12-month discontinuation data indicated that a significantly higher percent of ICD users (22.4) discontinued their device than did either LNG-IUD (7.0) or Nova-T (8.7) users. However, we were no longer able to detect significant differences in discontinuation after controlling for baseline variables that assessed predisposition to be dissatisfied with contraception in general. Adjusted probabilities of discontinuing the ICD, LNG-IUD, and Nova-T were 11.8%, 6.2% and 7.9%, respectively. These data indicate that the ICD is likely to be acceptable to Helsinki clinic patients; moreover, they suggest a definite place for hormonal intrauterine devices in the contraceptive armamentarium. Most importantly, the methodology used here can be generalized to acceptability studies of other contraceptive devices and drugs undergoing Phase I and early Phase II clinical trials (in situations where randomization may not be feasible) in order to identify and control for the bias introduced by nonrandom assignment procedures.

Adolescent↗
PubMed1993

PC program extending the two-stage polynomial growth curve model to allow missing data.

A stand-alone, menu-driven PC program, written in GAUSS386i, extending the analysis of one-sample longitudinal data sets satisfying the two-stage polynomial growth curve model (Ten Have et al., Am J Hum Biol, 3 (1991) 269-279) to allow missing data is described, illustrated and made available to interested readers. The method and the program are illustrated using data previously analyzed by the authors (Schneiderman and Kowalski, Am J Phys Anthropol, 67 (1985) 323-333) but with several randomly chosen data points discarded and treated as missing.

Animals↗
PubMed1995

Maximum a posteriori estimation of change points in the EEG.

A new approach for EEG segmentation is introduced. This is based on a methodology for optimal segmentation of non-stationary signals derived from the maximum a posteriori estimation principle. It is a model-based, not sequential approach that allows for segmentation at different resolution levels. The features of the methodology are illustrated by its application to EEG recordings containing several types of spectral changes due to normal and pathological variations of spontaneous brain rhythmic activities, as well as physiological artifacts.

Algorithms↗