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At least 1,009 records · Page 56Linked to original sources
PubMed2003

[Transrectal ultrasound-guided punch biopsies of the prostate. Indication, technique, results, and complications].

The golden standard for diagnosis of prostate cancer is transrectal ultrasound-guided systematic biopsy (TRUS-Bx). The optimal number of cylinders, sampling design, and indications for repeat biopsy are still in a state of flux. At the beginning of the 1980s, considerable doubts persisted regarding the benefit of ultrasound-guided punch biopsy for the diagnosis of prostate cancer. The examination on a chair with a fixed ultrasound head caused the patient substantial discomfort. Besides, in the pre-PSA era, most prostate carcinomas were detected by palpation and digitally guided biopsies were easily obtained. Indeed, the DRU procedure alone exhibited low sensitivity. Keetch et al. found that in only 25% of patients with abnormal palpatory findings and PSA between 4 and 20 ng/ml was a carcinoma revealed upon biopsy. On the other hand, patients with suspicious palpatory findings and proven malignancy suffered more frequently from locally advanced and systemic metastasizing tumors. As a result of restaging based on PSA, in most series more than half of the detected carcinomas presented normal palpatory findings. Ultrasound examination made precise imaging of zonal structures possible and thus offered the advantage of precision guidance for tissue biopsy despite lower sensitivity and specificity for diagnosis of suspicious lesions. Furthermore, calculation of prostate volume was possible. At the end of the 1980s, Hodge defined the systematic sextant biopsy as the first golden standard for early detection of prostate cancer. This meant the systematic removal of three punch cylinders from both lateral lobes of the prostate in the parasagittal midline at various levels (apex, middle, and base).

Adult↗
PubMed2004

The phenomenon of somatization among community Chinese Americans.

OBJECTIVE: The phenomenon of somatization was explored in relation to the experiences of acculturation, stress, support, and distress. METHODS: A representative community sample of 1,747 Chinese Americans (aged 18-65 years), selected by a multi-stage household sampling design, in the Los Angeles County was interviewed to tap their psychiatric diagnoses, symptomatology, level of acculturation, stress, and support. RESULTS: Across all indices, Chinese Americans' level of somatic symptoms, impairment related to somatization, and percentage of meeting the Somatic Symptom Index 5/5 (SSI 5/5) criterion were comparable to those found in other populations. Length of residence in the U. S. and acculturation were not related to somatization. Regression analyses showed that anxiety, depression, gender, age, education, stressors, and support were significantly related to somatization, ps < 0.05. Somatizers tended to perceive themselves with poor health and utilized both Western and indigenous Chinese medicine. CONCLUSION: The importance of demographics, psychological distress, and stress was emphasized in the explanation of somatization tendencies among immigrant Chinese Americans. Somatization might be a stress response with regard to increased distress severity and psychosocial stressors rather than a cultural response to express psychological problems in somatic terms.

Acculturation↗
PubMed2002

Transmission disequilibrium test for hand bone mineral density and 11q12-13 chromosomal segment.

The main aim of the present study was to test the hypothesis that the bone mineral density (BMD) assessed from radiographs of the hand phalanges in a random sample of ethnically homogeneous pedigrees is linked to the 11q12-13 chromosomal segment. The data for the study were gathered from 574 Chuvasha individuals belonging to two- and three-generation pedigrees who live in small villages in the Bashkortostan autonomy, Russia. Preliminary statistical-genetic analysis of the BMD in the pedigrees studied showed that potential genetic effects were highly significant ( p<0.001, in comparison with the model assuming no genetic effect), and explained at least 36% of the BMD variation adjusted for sex and age differences. For the transmission/disequilibrium test (TDT) used in our study, a total of 163 nuclear families with two sibs on average were available. Seven DNA microsatellite markers ( D11S1313, D11S1765, D11S987, D11S913, D11S983, D11S1314, D11S916) with average spacing of 2 cM on the chromosomal area 11q12-13 were selected for the TDT. The nominal p values ( p<0.05-0.0015) obtained from three TDT-type tests used for random and extreme-threshold sampling designs pointed consistently to possible linkage disequilibrium between BMD and some of the DNA markers. There was evidence for possible linkage disequilibrium in the upper part of the chromosomal segment studied (markers D11S1313 and D11S1765), and also in the lower part (markers D11S1983 and D11S1314). The lowest nominal p values (0.0015-0.0067) were obtained from three TDT-type tests for marker D11S1313. However, our findings must still be treated with great caution.

Adult↗
PubMed2005

Reinforcing effects of caffeine and theobromine as found in chocolate.

RATIONALE: Although in a previous study we showed that caffeine and theobromine were the main psychopharmacologically active constituents in a 50-g bar of chocolate, mere activity does not guarantee a role in our liking for the food. OBJECTIVES: Our aim was to see if liking for a drink repeatedly paired with these amounts of caffeine and theobromine would increase compared to a placebo-paired drink. METHODS: Participants (n=64) consumed a 'novel' drink + treatment capsule on six non-consecutive mornings using a double-blind, placebo-controlled independent-sample design. Aspects of liking and intensity of various sensory descriptors for these drinks were measured at every drink collection. Treatment capsules contained either an ecologically relevant dose combination of 19-mg caffeine and 250-mg theobromine or a placebo. RESULTS: Liking for the drink paired with the methylxanthine-containing capsules increased over time compared to the placebo-paired drink. This highly significant effect was confirmed by subjective, retrospective changes in liking for the drink. CONCLUSIONS: Methylxanthines in amounts found in 50-g chocolate may well contribute to our liking for chocolate, especially to the more acquired taste for dark chocolate.

Adolescent↗
PubMed1997

Mercury concentrations in pond fish in relation to a coal-fired power plant.

Many studies have reported that atmospheric mercury is the primary cause for bioaccumulation in fish from remote lakes. Few data, however, are available on the possible effects of near-field mercury deposition on mercury concentrations in fish from local waters. Mercury concentrations were surveyed in fish from 23 ponds in the vicinity of a 543-megawatt coal-fired power plant located at Dickerson, Maryland. A stratified random sampling design was used to select ponds within zones delineated by concentric arcs mapped at 3, 7, 10, and 15 km from the plant. For each pond, mercury concentrations were measured by atomic absorption spectrometry in sunfish (bluegill or green sunfish) in all ponds, and largemouth bass, which were present in 14 of the ponds. Mean mercury concentrations in the ponds ranged from 0.01 to 0.38 ppm for sunfish and 0.04 to 0.43 ppm for bass. Stepwise multiple regression identified variables related to tissue concentrations. Differences between strata were tested with analysis of covariance, after adjusting the concentrations to account for differences in water quality. The observed pattern of mercury bioaccumulation did not match the pattern predicted by a wet deposition model.

Animals↗
PubMed1998

In Situ Investigation of Trace Metal Availability in Industrial Effluents Using Transplanted Aquatic Mosses

Three species of aquatic mosses, Rhynchostegium riparioides, Fontinalis antipyretica, and Cinclidotus danubicus, were collected from the same reference location and exposed in five industrial effluents. The purpose was to test their suitability for assessing trace metal contamination under adverse and contrasted environmental conditions. Two distinct experiments of 16 and 11 days were conducted. In spite of short residence times in the effluents, the bryophytes were considerably affected at several sites, showing a light green to yellowish color, brown-edged leaves, and even dead strands. Cinclidotus danubicus was the most resistant whereas Fontinalis antipyretica was the most sensitive species. The observed physiological damage had no obvious incidence on the accumulation capacity of the mosses. The biomonitors provided time-integrated patterns of trace metal bioavailability (copper, chromium, nickel, lead, and zinc) in the effluents with a clear discrimination between poorly, moderately, and heavily polluted sites. Compared to water analyses, these more reliable indications could be obtained with a considerably reduced sampling design. When substantial accumulation occurred in mosses, the highest concentrations were systematically found in Rhynchostegium riparioides and the lowest in Cinclidotus danubicus. As only quantitative, not qualitative, differences were observed, all investigated moss species can be recommended for the assessment of trace metals in effluents at their discharge into the natural environment.

Journal Article↗
PubMed2002

Large-scale effects of timber harvesting on stream systems in the Ouachita Mountains, Arkansas, USA.

Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected for three years (1990-1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences, year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features. Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect with our sampling design and analyses.

Animals↗
PubMed2000

Sandhoff disease in Cyprus: population screening by biochemical and DNA analysis indicates a high frequency of carriers in the Maronite community.

In the last 15 years, four patients with the infantile form of Sandhoff disease were diagnosed in four different families in Cyprus (population 703,000, birth rate 1.7%). Three of these cases came from the Christian Maronite community (less than 1% of the population) and one from the Greek community (84% of the population). This relatively large number of patients prompted us to initiate an epidemiological study in order to establish the frequency of the mutant allele in Cyprus. Carrier detection was initially based on the measurement of beta-hexosaminidase A and B in both leucocytes and serum. Using the enzyme test, 35 carriers were identified among 244 random Maronite samples and 15 among 28 Maronites with a family history of Sandhoff disease, but only one carrier was found out of 115 random samples from the Greek community. In parallel to the biochemical screening, DNA studies were undertaken in one of the three Maronite patients and in a Greek carrier related to the Greek patient. These studies resulted in the identification of two novel mutations, a deletion of A at nt76 and a G to C transversion at position 5 of the 5'-splice site of intron 8, which have been published. We subsequently screened the carriers detected in the biochemical study for these two mutations using PCR-based tests. Of 50 Maronite carriers examined, 42 were found to have the nt76 deletion. Eight Maronite samples, designated carriers from the biochemical results, were negative for both mutations. It is possible that these individuals were incorrectly classified as carriers since their enzyme values are equivocal, although the presence of another mutation has not been excluded. Two Greek Cypriot carriers and two obligate Lebanese carriers were negative for both mutations. We conclude that there is a high frequency of Sandhoff disease carriers in the Maronite community of Cyprus, approximately 1 in 7, and that a single mutation predominates in this population.

Cyprus↗
PubMed2003

Estimating scale-dependency in disturbance impacts: El Niños and giant kelp forests in the northeast Pacific.

Recent discussions on scaling issues in ecology have emphasized that processes acting at a wide range of spatial and temporal scales influence ecosystems and thus there is no appropriate single scale at which ecological processes should be studied. This may be particularly true for environmental disturbances (e.g. El Niño) that occur over large geographic areas and encompass a wide range of scales relevant to ecosystem function. However, it may be possible to identify the scale(s) at which ecosystems are most strongly impacted by disturbances, and thus provide a measure by which their impacts can be most clearly described, by assessing scale-dependent changes in the patterns of variability in species abundance and distribution. This, in turn, may yield significant insight into the relative importance of the various forcing factors responsible for generating these impacts. The 1997-98 El Niño was one of the strongest El Niños ever recorded. I examined how this event impacted giant kelp populations in the northeast Pacific Ocean at 90 sites ranging from central Baja California, Mexico to central California, USA. These sites spanned the geographic range of giant kelp in the Northeast Pacific and were surveyed just before, immediately following, several months after, more than 1 year after, and nearly 2 years after the El Niño. I used a hierarchical sample design to compare these impacts at five spatial scales spanning six orders of magnitude, from a few meters to more than 1,000 km. Variance Components Analyses revealed that the El Niño shifted control over giant kelp abundance from factors acting at the scale of a few meters (local control) to factors operating over hundreds to thousands of kilometers (regional control). Moreover, El Niño resulted in the near-complete loss of all giant kelp throughout one-half of the species' range in the northeast Pacific Ocean. Giant kelp recovery following El Niño was far more complex and variable at multiple spatial scales, presumably driven by numerous factors acting at those scales. Recovery returned local control of giant kelp populations within 6 months in southern California, and within 2 years in Baja California.

California↗
PubMed2000

Use of Competitive PCR to Detect and Quantify Haplosporidium nelsoni Infection (MSX disease) in the Eastern Oyster (Crassostrea virginica).

This study was undertaken to develop a quantitative polymerase chain reaction assay that would improve the utility of PCR for detecting Haplosporidium nelsoni (MSX), a serious parasite of the eastern oyster Crassostrea virginica. A competitive PCR sequence was generated from the H. nelsoni small subunit ribosomal DNA fragment, originally described by Stokes and colleagues, that was amplified by the same PCR primers and had similar amplification performance. Assays performed using competitor dilutions ranging from 0.05 to 500 pg/µl DNA were used to test oyster samples designated using histological techniques as having "light" or "heavy" MSX infections. Visual diagnoses were confirmed equally well with three methods: densitometry of ethidium-bromide-stained agarose, densitometry of SYBRGreen-stained polyacrylamide gels, and analysis by GeneScan 3.0 of fluorescent products detected in ultrathin gels. Oysters diagnosed as negative for MSX tested as negative or light by PCR. Oysters with light MSX infections generally had less than 5 pg/µl infectious DNA. Oysters with heavy infections generally corresponded to 5 pg/µl or greater competitor dilutions.

Journal Article↗
PubMedDate not supplied

The current status of visual disability in the elderly population of Taiwan.

PURPOSE: This study was conducted to explore the prevalence and the associated factors of visual impairment and blindness among the elderly Taiwanese population. METHODS: A nationwide population-based visual health care screening program of elderly people aged 65 years or older was conducted between 1 July 2002 and 31 December 2002 in Taiwan. Based on the same standardized protocol used by the Bureau of Health Promotion, Department of Health, and a stratified random sampling design, 3160 out of 5000 elderly subjects were selected by a two-stage visual care screening method. The overall response rate was 63.2%. RESULTS: The mean age of the elderly participants was 72.4 +/- 5.1 years. The overall prevalence of glaucoma, corneal diseases, trauma, cataracts, myopic or diabetic retinopathy, and age-related macular degeneration among the elderly population was 2.1%, 6.3%, 0.9%, 60.2%, 7.5%, and 2.9%, respectively. The overall prevalence of visual disability (visual acuity of the better eye <0.5) was 17.7%, including 17.1% with visual impairment and 0.6% with blindness. Based on logistic regression, the significant independent factors of visual disability (visual impairment plus blindness) were sex (male vs. female, odds ratio (OR) = 0.62, 95% confidence interval (CI), 0.51-0.76), age (70-74 years vs. 65-69 years, OR = 1.60, 95% CI, 1.24-2.06; 75-79 years vs. 65-69 years, OR = 2.52, 95% CI, 1.92-3.32, > or =80 yrs vs. 65-69 yrs, OR = 4.86, 95% CI, 3.52-6.70), corneal diseases (OR = 2.26, 95% CI, 1.61-3.16), myopic or diabetic retinopathy (OR = 1.69, 95% CI, 1.20-2.39), age-related macular degeneration (OR = 4.96, 95% CI, 3.16-7.78), and cataract (OR = 3.40, 95% CI, 2.67-4.33). CONCLUSIONS: The geographic difference in the prevalence of vision-related eye disease, visual impairment, and blindness point to the importance of taking actions that suit local circumstances. Our results also revealed that visual impairment and blindness are important visual health problems in the elderly Taiwanese population. Age-related macular degeneration, cataracts, corneal diseases, myopic or diabetic retinopathy, female sex, and aging were the leading causes of visual disability. Further organized preventive strategies for eye care are recommended in this population.

Age Distribution↗
PubMed2006

Spatial correlation analysis of isotropic microvessels: methodology and application to thyroid capillaries.

The study of relations between structural organization and functions of microcirculatory networks is a major aim of modern microangiology. Such a structural aspect of microvessels (MVs) as their spatial arrangement has substantial influence on their transport and other functional properties. This paper describes a methodology of spatial correlation analysis for isotropic blood and lymphatic MVs which is based on a stereological estimator of the pair correlation function [g3D(r)] created recently by the authors for systems of elongated objects. The following main features of the methodology are presented: (i) interpretation of the shape of g3D(r) curves, (ii) their quantitative description by numerical parameters, and (iii) limitations of the method arising from statistical requirements to MVs under investigation. The methodology is considered in the light of multilevel sampling designs, which are typical for biomedical morphology. The estimator with its methodological framework is applied to perifollicular blood capillaries in the adult rat thyroid. Related methods for studying the spatial arrangement of MVs are thoroughly discussed in the paper.

Albinism↗
PubMed2006

A phase 1 trial of XK469: toxicity profile of a selective topoisomerase IIbeta inhibitor.

PURPOSE: XK469, a member of the quinoxaline family of antitumor agents, is believed to be unique in its ability to selectively target topoisomerase IIbeta. Based on encouraging pre-clinical data, a phase I trial was conducted to determine the dose limiting toxicity (DLT) and the maximum tolerated dose (MTD). METHODS: A 2B accelerated titration schema was employed. XK469 was administered as a 5 or 20 min IV infusion on days 1-5 every 21 days. The starting dose was 9 mg/m(2). Pharmacokinetics (PK) were conducted in cycles 1-3. RESULTS: 22 patients (21 evaluable, mean age: 56 years, median performance status: 1) were enrolled. At dose level 11 (260 mg/m(2)/daily X 5), 1/6 patients experienced a DLT of grade 4 neutropenia. At 346 mg/m(2)/daily X 5, 2/2 patients experienced DLT's with one episode of febrile neutropenia and one grade 3 infection. The MTD was identified as 260 mg/m(2)/day. XK469 peak plasma levels and systemic exposure were proportional to dose indicating linear pharmacokinetics. However, secondary peaks in the PK profiles and a rapid decline in drug level from 23 to 24 h occurred in some patients. Drug infusion in the afternoon followed by dense sampling of levels during the elimination phase supported the hypothesis that the drug was being sequestered. No anti-tumor activity was identified. CONCLUSIONS: Traditional PK sampling designs were inadequate to describe XK469 disposition. XK469 and related structures work through a unique mechanism of action. A further understanding of the specific mechanism of these compounds might uncover a unique avenue for future drug development.

Adolescent↗
PubMed2005

Contemplating the assessment of great river ecosystems.

The science and practice of assessing the status and trends of ecological conditions in great rivers have not kept pace with perturbation wrought on these systems. Participants at a symposium sponsored by the U.S. Environmental Protection Agency (USEPA) and the Council of State Governments concluded that useful and efficient assessments of great river ecosystems require thoughtful alignment of sampling designs, spatial and temporal scales, indicators, management needs, and ecosystem characteristics. Site-specific physical, chemical, and biological data long accumulated by monitoring programs have value but fail to provide the integrated system-wide perspective required for adaptive management and the Clean Water Act. Use of existing data may be limited by methodological incompatibilities, access difficulties, and the exclusive applicability of data to specific habitats or sites. The transition from site-specific to system-wide assessments benefits from research being done by USEPA's Environmental Monitoring and Assessment Program (EMAP) and other programs that use probability surveys and biological indicators. Indicators of various taxa (in particular fish, algae, and benthic invertebrates) have been successfully developed for great rivers. However, optimizing the information these ecological indicators convey to managers and the public is the subject of ongoing research.

Conservation of Natural Resources↗
PubMed2006

Relationship between asthma, overweight, and physical activity among U.S. high school students.

Asthma is a leading chronic illness among children and adolescents in the United States. This study examined the relationship between asthma and both overweight and physical activity levels. Results are based on data from the Centers for Disease Control and Prevention's 2003 national Youth Risk Behavior Survey, a cross-sectional survey of health risk behaviors among a representative sample of high school students in the United States. The overall survey response rate was 67% and the results are based on weighted data. SUDAAN was used for all data analysis (prevalence estimates and logistic regression) because it accounts for the complex sampling design of the survey. Significantly more students with current asthma than without were overweight (odds ratio [OR] = 1.4; 95% confidence interval [CI] = 1.1, 1.6) and described themselves as overweight (OR = 1.2; 95% CI = 1.0, 1.4). Significantly more students with current asthma than without used a computer for non-schoolwork 3 or more hours/day (OR = 1.3; 95% CI = 1.1, 1.5). No significant differences were found for participation in sufficient vigorous or moderate physical activity or strengthening exercises among students with and without current asthma. Unlike some other risk factors for developing or exacerbating asthma, overweight and physical activity are generally modifiable. School and community policies and programs can play an important role in asthma management, including promoting the maintenance of an appropriate weight and encouraging continued physical activity.

Adolescent↗
PubMed2006

Nativity and cardiovascular disease screening practices.

Cardiovascular diseases (CVD) are the leading causes of death among Mexican American adults living in the United States. Using data from a modified Behavioral Risk Factor Surveillance Survey and guided by the Anderson Model, this study examined the effect of nativity on CVD screening practices among 423 Mexican American adults living in Chicago. Dependent variables included having had a blood pressure and cholesterol screening and a routine check up in the past 2 years. Multivariate analyses were used to control for sociodemographic factors, while accounting for complex sampling design. Compared to those born in Mexico, US-born Mexican Americans had significantly greater odds of obtaining blood pressure (OR=5.61), and cholesterol screenings (OR=1.60) and having a routine checkup (OR=2.69) in the past 2 years. Health professionals with an agenda to increase screenings for CVD risk factors among Mexican Americans living in northern cities should understand the impact of nativity on screening practices.

Adolescent↗
PubMed2006

An innovative, effective and cost effective survey method using a survey-check response format.

Maximizing the response rate to surveys involves thoughtful choices about survey design, sampling and collection methods. This paper describes an innovative survey method, to provide immediate reinforcement for responding and to minimize the response cost. This method involves using a questionnaire printed as checks on security (anti-fraud) paper with questions and responses separated using a perforated tear off section. Once a participant completes the survey, the response area is detached from the questions, thus protecting the confidentiality of the subject, and the check is returned via the banking system. This report describes the survey-check methodology, the survey flow process, and the results from four research studies which have used this method. These studies include (1) a technology accessibility survey of parents with children enrolled in a low-income preschool program; (2) a parent report of their child's behavior used as screening criteria for inclusion in a computer-mediated parent education project; (3) a follow-up questionnaire as part of a longitudinal study of child behavior, covering home and classroom interventions, and service utilization, and; (4) a survey of dentists in support of efforts to recruit them to participate in a randomized control trial of tobacco cessation in dental offices. The results of using this method show great improvement in response rates over traditionally administered surveys for three of the four reported studies. Results are discussed in terms of future applications of this method, limitations, and potential cost savings.

Cost-Benefit Analysis↗
PubMed1977

Collaborative US-USSR study on the prevalence of dyslipoproteinemias and ischemic heart disease in American and Soviet populations. Prepared by the US-USSR Steering Committee for Problem Area 1: the pathogenesis of atherosclerosis.

The ongoing collaborative US-USSR study of the prevalence of dyslipoproteinemias, based on the Lipid Research Clinics Study protocol, is described. The purpose of this multidisciplinary, multiclinic program is to investigate the relation of plasma lipids and lipoproteins and other risk factors to atherosclerotic disease in selected populations. The research design, sampling strategy and general hypotheses of the study are detailed. Common quality control methods and standardized screening procedures used in data collection are reviewed. Components of the study include measurement of plasma lipids and lipoproteins, the collection of demographic and physiologic information, a 24-hour dietary recall, administration of the Rose questionnaire and resting and exercise electrocardiograms. Preliminary comparative data for total plasma cholesterol, triglycerides and high density lipoprotein cholesterol are presented for men aged 40 to 59 years.

Arteriosclerosis↗