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At least 883 records · Page 49Linked to original sources
PubMed2002

[The prevalence of pain in the elderly German population: results of population-based studies with the Giessen Subjective Complaints List (Giessener Beschwerdebogen GBB)].

METHODS: In a separate population-based cross-sectional study (n = 593; 53,62% female) using the short form of the Giessen Subjective Complaints List (Giessener Beschwerdebogen GBB-24), data was collected on current pain in various parts of the body (limbs, back, neck, head, stomach). RESULTS: Rheumatic pain is most frequent in the elderly. At the age of 76 years or older more than 90% are affected from this form of pain. Even if the frequency of pain in the highest grading is lightly higher for women than for men, there are only few significant sex-related effects. Furthermore, there are only few age-related effects beyond the age of 60. CONCLUSIONS: The results show that pain is a common problem in the elderly.

Aged↗
PubMed2004

The Gladiator Sparrow: ethical issues in behavioral research on captive populations of wild animals: a case study with commentaries exploring ethical issues and research on wild animal populations.

This case involves invasive research on captive wild populations of birds to study aggressive animal behavior. The case and associated commentaries raise and examine fundamental issues, whether and under what conditions, such research is ethically justified when the research has no expected, direct application to the human species; the moral status of animals and how one balances concern for the animal's interests against the value of gains in scientific knowledge. They also emphasize the issue of the importance of a thorough literature search to ensure appropriate research design and experimental design to minimize animal suffering. It raises the issue of circumstances in which such research should be modified or terminated.

Aggression↗
PubMed1991

Evaluation of seasonality in six clinical populations and two normal populations.

The Seasonal Pattern Assessment Questionnaire (SPAQ) was used to evaluate retrospectively self-reported seasonal changes in mood and behavior (seasonality) of two normal and six clinical populations: patients with winter-seasonal affective disorder (SAD), summer-SAD, eating disorders, bipolar affective disorder, major depressive disorder and subsyndromal winter-SAD. The SPAQ successfully discriminated between groups expected to have high seasonality scores, such as winter-SAD, summer-SAD and subsyndromal winter-SAD, and normal controls. Bipolars and major depressives had normal seasonality scores. Patients with eating disorders had unexpectedly high scores. There was a general tendency for all groups to eat and sleep more and to gain weight in the winter. The implications of these findings are discussed.

Adult↗
PubMed1981

Expansion of human lymphocyte populations expressing specific immune reactivities. III. Specific colonies, either cytotoxic or proliferative, obtained from a population of responder cells primed in vitro. Preliminary immunogenetic analysis.

Human alloreactive cell lines were maintained in culture over prolonged periods of time using conditioned medium. Primed lymphocyte typing reactivity was observed in these T cell lines for only 1 mo, but these T cell lines have remained for more than 7 mo highly and specifically cytotoxic. Using as growth promoter an irradiated autologous feeder consisting of irradiated peripheral blood lymphocytes and the lectin leucoagglutinin, we have derived by limiting dilution cloning of in vitro primed allogeneic combinations, primary colonies (or primary clones) with monofunctional immune reactivities: either cytotoxic (the rarest observed) or PLT reactive (the majority of the colonies). Furthermore, each monofunctional primary colony when tested for PLT or CML reactivity on a panel of unrelated PBL, always showed a restricted specificity when compared to the original primed population. The PLT reactivity of each of the primary clones was short lasting in contrast to their growth potential. The CML reactivity of the primary clones, as for the T cell lines, was long lasting as was their growth potential.

Cells, Cultured↗
PubMed2005

Rat limbal epithelial side population cells exhibit a distinct expression of stem cell markers that are lacking in side population cells from the central cornea.

The side population (SP) phenotype is shared by stem cells in various tissues and species. Here we demonstrate SP cells with Hoechst dye efflux were surprisingly collected from the epithelia of both the rat limbus and central cornea, unlike in human and rabbit eyes. Our results show that rat limbal SP cells have a significantly higher expression of the stem cell markers ABCG2, nestin, and notch 1, compared to central corneal SP cells. Immunohistochemistry also revealed that ABCG2 and the epithelial stem/progenitor cell marker p63 were expressed only in basal limbal epithelial cells. These results demonstrate that ABCG2 expression is closely linked to the stem cell phenotype of SP cells.

ATP Binding Cassette Transporter, Subfamily G, Mem↗
PubMed2004

An algorithm for real-time extraction of population EPSP and population spike amplitudes from hippocampal field potential recordings.

A new method is presented for extracting the amplitude of excitatory post synaptic potentials (EPSPs) and spikes in real time. It includes a low pass filter (LPF), a differentiator, a threshold function, and an intelligent integrator. It was applied to EPSP and population spike data recorded in the Dentate Gyrus and the CA1 hippocampus in vitro. The accuracy of the extraction algorithm was evaluated via the extraction normalized mean square error (eNMSE) and was found to be very high (eNMSE < 5%). The preservation of neuronal information was confirmed using the Volterra-Poisson modeling approach. Volterra-Poisson kernels were computed using amplitudes extracted with both proposed and traditional methods. The accuracy of the computed kernels and the resulting model was evaluated via the prediction normalized mean square error (pNMSE) and was found to be very high (pNMSE < 5%). The similarity between the kernels computed when the proposed method was used to extract the field potential amplitude and their counterparts when the traditional method was used to extract the field potential amplitude confirms the preservation of the neuronal dynamics. The proposed method represents a new class of real time field potential amplitude extraction algorithms with complexity that can be included in hardware implementations.

Action Potentials↗
PubMed2005

Prostate-specific antigen screening in a high-risk population: lessons from the community and how they relate to large-scale population-based studies.

OBJECTIVES: To estimate the incidence of prostate cancer among African-American men and Caribbean immigrants to the United States, to assess the applicability of large-scale prostate screening trials to a community screening program, and to recruit unscreened men. METHODS: African-American and Caribbean-American men were targeted with a community-based prostate cancer screening program in Jamaica, New York. Serum prostate-specific antigen determination and digital rectal examination were used to determine abnormal findings. The incidence of an abnormal screening examination was used to project the incidence of prostate cancer, which was compared with that in other reported trials. RESULTS: The projected incidence of prostate cancer among African-Americans and Caribbean-Americans older than 50 years was 8% and 7%, respectively, similar to that reported in other trials of African-American men. The projected incidence of prostate cancer in Caribbean-American men aged 40 to 49 years was 1%, the same as the high rate reported among Caribbean men. As in other trials, a family history of prostate cancer and age were strong predictors of abnormal findings. Of the recruited men older than 50 years, 58% had never been screened compared with 42% nationally. CONCLUSIONS: Large population-based screening trials have identified ethnic groups at high risk of prostate cancer. This trial detected high rates of abnormal screening findings by targeting ethnicity. The incidence of an abnormal examination was high in Caribbean-American men younger than 50 years old. Finally, this trial successfully recruited underscreened men.

Adult↗
PubMed2005

Coculture with endothelial cells reduces the population of cycling LeX neural precursors but increases that of quiescent cells with a side population phenotype.

Neural stem cell proliferation and differentiation are regulated by external cues from their microenvironment. As endothelial cells are closely associated with neural stem cell in brain germinal zones, we investigated whether endothelial cells may interfere with neurogenesis. Neural precursor cells (NPC) from telencephalon of EGFP mouse embryos were cocultured in direct contact with endothelial cells. Endothelial cells did not modify the overall proliferation and apoptosis of neural cells, albeit they transiently delayed spontaneous apoptosis. These effects appeared to be specific to endothelial cells since a decrease in proliferation and a raise in apoptosis were observed in cocultures with fibroblasts. Endothelial cells stimulated the differentiation of NPC into astrocytes and into neurons, whereas they reduced differentiation into oligodendrocytes in comparison to adherent cultures on polyornithine. Determination of NPC clonogenicity and quantification of LeX expression, a marker for NPC, showed that endothelial cells decreased the number of cycling NPC. On the other hand, the presence of endothelial cells increased the number of neural cells having "side population" phenotype, another marker reported on NPC, which we have shown to contain quiescent cells. Thus, we show that endothelial cells may regulate neurogenesis by acting at different level of NPC differentiation, proliferation and quiescence.

Animals↗
PubMed1998

Recruitment strategies in the women's health trial: feasibility study in minority populations. WHT:FSMP Investigators Group. Women's Health Trial:Feasibility Study in Minority Populations.

The Women's Health Trial:Feasibility Study in Minority Populations (WHT:FSMP) examined the feasibility of recruiting postmenopausal women from a broad range of racial and socioeconomic backgrounds into a primary prevention trial requiring marked reductions in dietary fat. Postmenopausal women aged 50-79 yr who had no history of cardiovascular disease or cancer and who consumed 36% or more total energy from fat qualified to participate. We randomized the women into dietary intervention (60%) or control (40%) groups; we aimed to randomize 750 women in 18 months in each of the three clinical centers. All centers achieved goals for randomization based on ethnicity, and two centers exceeded overall recruitment goals. The greatest source of randomized participants was mass mailing, followed by items in the media, referrals, and community outreach. Recruitment yields were generally similar for the ethnic groups but lower for less-educated participants. The experience of WHT:FSMP indicates that postmenopausal women from the African-American, Hispanic, and non-Hispanic white communities can be recruited into dietary intervention studies for the prevention of disease.

Black or African American↗
PubMed1982

Study of kinetics of epithelial cell populations in normal tissues of the rat's intestines and in carcinogenesis. III. Changes in kinetics of enterocyte populations in the course of experimental intestinal tumour induction in rats.

A stage-by-stage study of disturbances in enterocyte proliferation in the ileum and descending colon in the course of tumour induction by treatment with 1,2-dimethylhydrazine was performed. Even at early stages, an expansion of the zone of epithelial cell proliferation in the crypts and migration of dividing cells as far as to the crypt mouth, which is a manifestation of enterocyte differentiation disturbances, were observed. Enterocytes of the crypts chiefly proliferated through a short cycle, the mean duration of which was slightly greater than in normal intestinal tissue. The reduced cell loss in the epithelium and resultant disturbances of its steady state led to the accumulation of great numbers of atypical cells in the superficial layers of the crypts and formation of carcinomas in situ in the descending colon. The microscopically unaltered sections of the mucosa, prior to development of overt neoplastic changes carcinomas in situ, superficial cancers and small-size adenocarcinomas revealed a simplified structure of enterocyte population, as compared with normal epithelium. As tumours progressed, the heterogeneity of its component cell subpopulations increased, and several subpopulations, differing in mean duration of the mitotic cycle, were formed. Pathologic mitoses made up a greater portion (50-60 per cent) of the dividing cells of the descending colon, as compared with ordinary 4 per cent at all stages of experimental tumour induction.

1,2-Dimethylhydrazine↗
PubMed2004

Improving population health or the population itself? Health technology assessment and our genetic future.

The province of British Columbia (BC), Canada is developing its first population-wide prenatal genetic screening program, known as triple-marker screening (TMS). TMS, initiated with a simple blood test, is most commonly used to screen for fetuses with the chromosomal abnormality known as Down syndrome or neural tube disorders. Women testing TMS-positive are offered diagnostic amniocentesis and, if the diagnosis is confirmed, selective second-trimester abortion. The project described in this study was initiated to address the broad range of issues arising from this testing technology and provides an example of the new type of health technology assessment (HTA) contribution emerging (and likely to become increasing necessary) in health policy development. With the advent of prenatal genetic screening programs, would-be parents gain the promise of identifying target conditions and, hence, the option of selective abortion of affected fetuses. There is considerable awareness that these developments pose challenges in every dimension (ethical, political, economic, and clinical) of the health-care environment. In the effort to construct an appropriate prenatal screening policy, therefore, administrators have understandably sought guidance from within the field of HTA. The report authors concluded that, within the restricted path open to it, the role of government is relatively clear. It has the responsibility to maintain equal access to prenatal testing, as to any other health service. It should also require maintenance of medical standards and evaluation of program performance. At the same time, policy-makers need actively to support those individuals born with disabilities and their families.

British Columbia↗
PubMed2001

Population pharmacokinetic-pharmacodynamic model of craving in an enforced smoking cessation population: indirect response and probabilistic modeling.

PURPOSE: A population pharmacokinetic-pharmacodynamic model accounting for placebo effect was used to relate nicotine concentration and enforced smoking cessation craving score measured by the Tiffany rating scale short form. METHODS: Twenty-four smokers were enrolled in a placebo-controlled, randomized, double-blind, three periods, crossover trial. The study objective was to describe the nicotine-induced changes on craving scores. Two modeling strategies based on a mechanistic (indirect response models with drug-related inhibition on the k(in) synthesis rate and with a drug-related stimulation of the k(out) removal rate were evaluated) and a probabilistic (logistic regression) approach were used. RESULTS: Placebo response model properly fitted the circadian changes on craving scores. The analysis revealed that the indirect response model with inhibition on k(in) was the preferred model for the smoking data whereas the preferred model for the Nicotine Replacement Therapy data was the one with stimulation on k(out). The logistic analysis showed that the nicotine concentration was a significant predictor of reduction in craving during the free-smoking period. CONCLUSIONS: Nicotine dosage regimen can influence the nicotine mechanism of action: an instantaneous delivery at an individually selected time seems to inhibit the onset of craving while constant delivery at a pre-defined time seems to attenuate the craving.

Adult↗
PubMed2001

High variability of HTLV-I in a remote population of Gabon as compared to that of a similar population of French Guiana.

An anomalous high frequency of ATL was observed in a remote 'noir maroons' village of French Guiana. Since it is not clear if HTLV-I is responsible for different frequencies of disease in different geographical areas, we undertook a comparison of the population with a similar one located in Gabon. We found a much higher degree of gp46 surface envelope glycoprotein sequence conservation in the Guianese village than in the Gabonese one.

Base Sequence↗
PubMed2004

Heterogeneity of breast cancer risk within the South Asian female population in England: a population-based case-control study of first-generation migrants.

South Asian women in England have a lower breast cancer risk than their English-native counterparts, but less is known about variations in risk between distinct South Asian ethnic subgroups. We used the data from a population-based case-control study of first-generation South Asian migrants to assess risks by ethnic subgroup. In all, 240 breast cancer cases, identified through cancer registries, were individually matched on age and general practitioner to two controls. Information on the region of origin, religious and linguistic background, and on breast cancer risk factors was obtained from participants. Breast cancer odds varied significantly between the ethnic subgroups (P=0.008), with risk increasing in the following order: Bangladeshi Muslims (odds ratio (OR) 0.33, 95% confidence interval (CI): 0.10, 1.06), Punjabi Hindu (OR 0.59, 95% CI: 0.33, 1.27), Gujarati Hindu (1=reference group), Punjabi Sikh (OR 1.23, 95% CI: 0.72, 2.11) and Pakistani/Indian Muslims (OR 1.76, 95% CI: 1.10, 2.81). The statistically significant raised risk in Pakistani/Indian Muslims increased with adjustment for socioeconomic and reproductive risk factors (OR 2.12, 95% CI: 1.25, 3.58), but was attenuated, and no longer significant, with further adjustment for waist circumference and intake of nonstarch polysaccharides and fat (OR 1.49, 95% CI: 0.85, 2.63). These findings reveal differences in breast cancer risk between South Asian ethnic subgroups, which were not fully explained by reproductive differences, but were partly accounted for by diet and body size.

Asia, Southeastern↗
PubMed2002

Cardiovascular mortality focusing on socio-economic influence: the low-risk population of Halland compared to the population of Sweden as a whole.

The aim of the study was to investigate the relationship between mortality from cardiovascular diseases (CVD) and socio-economic status (SES) in Sweden and to estimate to what extent the difference between a province with low mortality and the rest of Sweden was dependent on socio-economic factors. A population-based retrospective study with a historical prospective approach was performed covering a 10-y period in the province of Halland, Sweden, as well as Sweden as a whole. Altogether 1,654,744 men and 1,592,467 women were included, of whom 45,394 men and 43,403 women were from Halland, distributed according to SES. Multivariate analysis with Poisson regression was used. Relative risks with 95% confidence intervals were calculated. Both men and women with a low SES showed a significantly higher risk of death from CVD in Sweden as a whole. The risk was 23% higher for male blue-collar workers and 44% higher for female blue-collar workers when compared to their white-collar counterparts. The level of mortality in Halland was 14% lower compared to the country as a whole when only age was taken into account. When the socio-economic variable was also included, this figure was 8%. The results show the substantial significance of social differences with respect to CVD mortality. The effect of SES seems to be more important than that of geographical conditions when the latter are isolated from socio-economic influence.

Adult↗
PubMed2001

Spirometric lung volumes in the adult Pacific Islander population: comparison with predicted values in a European population.

OBJECTIVE: Prediction equations for spirometric lung volumes have been developed mainly in Europe and North America and may not be relevant to Pacific Islanders. This study was undertaken to determine whether currently available prediction equations adequately describe spirometric lung volumes in the asymptomatic adult Pacific Islander population. METHODOLOGY: Healthy asymptomatic Pacific Island adults aged 15-70 years were recruited. Pulmonary function was measured in the laboratory at Green Lane Hospital, Auckland, New Zealand, in accordance with American Thoracic Society standards. Measured results were compared with predicted values derived from four sets of prediction equations relevant to, or currently used in, New Zealand. RESULTS: A total of 101 volunteers took part in the study; mean age 28 years (range 18-66 years), 39% male, body mass index = 32 (range 22-54). For forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC), when measured values were compared with reference values, the slopes of the regression lines were not significantly different from 1 and the intercepts were not significantly different from zero. Prediction equations derived for African-Americans did not provide a better fit than the prediction equations for Caucasians. Predictions were improved when ideal rather than actual bodyweight was used. CONCLUSION: Respiratory parameters (FEV1 and FVC) in healthy asymptomatic adult Pacific Islanders in New Zealand are adequately described by currently available prediction equations and no adjustment for ethnicity is required.

Adolescent↗
PubMed1998

The effects of age on the overall population and on sub-populations of myenteric neurons in the rat small intestine.

Previous studies on ageing animal and human subjects have demonstrated a significant overall decline in neuronal numbers in the myenteric plexus of the enteric nervous system (ENS). Our study aimed to confirm this observation by counting myenteric neurons stained with the panneuronal markers PGP 9.5 and NADH-diaphorase. We also wished to examine the possibility that particular subpopulations of neurons are vulnerable. Therefore, we have immunostained and counted a number of nerve cell groups within the myenteric plexus of old and young Sprague Dawley rats using markers which reflect some of the neuronal phenotypes present, including ChAT and VIP. The number of neurons demonstrating NADH-diaphorase activity was significantly reduced (P < 0.05) by approximately 15 % in old rats. However, the number of neurons stained for PGP 9.5 immunohistochemistry was not reduced and demonstrated larger numbers of neurons than the NADH-diaphorase method. None of the other neuronal markers studied showed any significant reductions with age. In contrast to previous work, this study has gathered little evidence for extensive cell loss in the myenteric plexus of the aged rat, either in overall populations, or in any of the principal functional groups of neurons.

Aging↗
PubMed1980

Enzyme null alleles in natural populations of Drosophila melanogaster: Frequencies in a North Carolina population.

A Raleigh, NC, population of Drosophila melanogaster was sampled for the presence of enzyme null alleles at 25 loci. No nulls were found at any of five X-linked loci. Nulls were recovered at 13 of 20 autosomal loci; the weighted mean frequency for all 20 autosomal loci was estimated to be 0.0025. A consideration of the effects of these null alleles on viability strongly suggests that, although they may contribute to so-called polygenic variation, they are not representative of the entire genome.

Journal Article↗