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PubMed1976

A technique for estimating life expectancy with crude vital rates.

This paper describes a method of estimating life expectancy at birth on the basis of crude vital rates. The method is derived from stable population theory and it furnishes good estimates insofar as the current crude vital rates of a population are close to its intrinsic rates. This condition is generally met in closed populations which have not experienced sharp movements in fertility. The method is useful for estimating life expectancy in developing nations with good sample registration systems but for which information on age is of poor quality. It is also useful for estimating the movement of life expectancy in certain European nations in the period prior to regular census taking. There are a number of nations and regions in Europe for which long series of birth and death rates are available but for which census age counts are widely spaced.

Birth Rate↗
PubMed2003

Phase II study of 1alpha-hydroxyvitamin D(2) in the treatment of advanced androgen-independent prostate cancer.

PURPOSE: In this single institution Phase II trial, we evaluated the efficacy of the vitamin D analogue, 1alpha-OH-D(2), in patients with advanced hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: The patients initially received 1alpha-OH-D(2) at 12.5 micro g p.o. every day, which was dose adjusted for hypercalcemia. Given the cytostatic nature of the drug, the primary study end point was progression-free survival for a minimum of 6 months. The secondary end point was further characterization of drug toxicity. RESULTS: A total of 26 patients was enrolled. Using the intent-to-treat population, stable disease was seen for an average of 19.2 weeks (median 12 weeks, range 3-108 weeks). Twenty patients were evaluable for response. The one patient that achieved disease stabilization for >2 years elected to come off-study because of patient preference. His last disease evaluation showed no evidence of progression. No objective responses were seen. Previous and ongoing clinical observations strongly imply that PSA could be a misleading surrogate marker for clinical effect with this type of drug. Therefore, prostate-specific antigen was not used as a marker for disease response. Toxicity was as expected with mild hypercalcemia and associated symptoms like constipation and prerenal azotemia seen in some patients. Six (30%) evaluable patients experienced stable disease for >6 months, suggesting possible cytostatic activity. CONCLUSION: The results of this and other trials suggest further clinical investigation in this disease with vitamin D analogues alone or in combination with other agents, such as chemotherapy, should be pursued.

Administration, Oral↗
PubMed1992

Human immunodeficiency virus (HIV) seroprevalence surveys.

The seroprevalence surveys being conducted in the Kansas City area have to date tested 15,778 persons and resulted in 85 seropositive HIV tests. The sexually transmitted disease (STD) surveys and women's surveys fall in the lowest quartile of the combined national surveys. The drug treatment (IVDU) survey data were comparable to the median national seroprevalence of 3.8%. Seroprevalence rates in the STD surveys were 41 times that of women's surveys, and the IVDU surveys were 104 times that of the women's surveys. Based on three years of data from clinics with stable populations presenting for treatment, no trends in the demographics of those being found seropositive were identified to be statistically significant. This lack of trends has been presented as the normal findings of surveys nationally. The data does not show an acceleration of new infections based on seropositives being identified in the survey sites.

Community Health Centers↗
PubMedDate not supplied

Migration and imaging of 111Indium-labelled lymphocytes in cardiac allograft rejection.

BACKGROUND: The diagnosis of cardiac allograft rejection is based on routine endomyocardial biopsy. To study an alternative method the authors evaluated the migration and scintigraphic imaging of 111Indium-labelled lymphocytes in a model of acute heart allograft rejection. METHODS AND RESULTS: Cervical heterotopic heart transplantation was performed in 10 dogs. Blood samples were harvested at 24 and 48 h after surgery for labelling of 36 +/- 6 x 10(6) lymphocytes with 6.62 +/- 0.56 MBq of 111Indium. Daily blood samples and heart biopsies were obtained for nuclear counting on the next three days; animals were sacrificed and both donor and native hearts were studied. Between 20 and 31% of autologous labelled lymphocytes remained in circulation until 72 h after injection. Maximal plasma 111Indium activity was 315 +/- 90 compared with 5513 +/- 1483 cpm/mL in whole blood (P less than 0.05). An average of 10,176 +/- 3444 labelled lymphocytes per gram of tissue were present in allograft biopsies while histological evaluation showed mild to moderate acute rejection. The ratio of tissue biopsy to blood 111Indium counts varied from 0.7 +/- 0.2, 6 h after autologous injection to 8.5 +/- 3.8 48 h later (P less than 0.05). At autopsy, 298 +/- 66 labelled cells per gram of tissue were present in native hearts compared with 2686 +/- 711 in allografts (P less than 0.05). Scintigraphic imaging using holospectral acquisition was performed; six lateral projections showed an indium activity ratio (transplanted heart to background tissue) of 2.8, 24 to 72 h after autologous injection of labelled cells. CONCLUSIONS: Labelling of a small number of lymphocytes with 111Indium gave a stable population of circulatory lymphocytes for studying migration of labelled cells into allografts and a noninvasive scintigraphic approach to diagnose cardiac allograft rejection.

Animals↗
PubMed2004

[A study on organotypic spinal cord slice culture].

This study was aimed at developing a method of organotypic culture of spinal cord slice. The slice culture was prepared using lumbar spinal cord from 8-day-old rat. The survival of alpha-motor neuron was evaluated by the morphological observation and by monoclonal antibody SMI-32, a nonphosphorylated neurofilament marker and immunohistochemical staining. Lactate dehydrogenase (LDH) level in culture medium was also measured. The result showed that the spinal cord explant could be maintained in the culture for more than 2 months with excellent cellular organization and stable population of ventral motor neurons. The level of LDH at different culture times had no significant difference. Organotypic spinal cord slice culture may provide an effective method for studying physiological and pathological changes, and neuroprotection of spinal cord.

Animals↗
PubMed1992

Osteoporosis risk assessment of mature working women: primary and secondary prevention strategies.

1. Occupational health nurses have a prime opportunity to promote a healthy and stable population of working women through teaching osteoporosis risk reduction behaviors and conducting periodic osteoporosis risk assessments. 2. Health teaching about osteoporosis prevention is needed to foster health promotion and risk reduction behaviors among pre-, peri-, and postmenopausal women to lessen the incidence of fractures and secondary consequences. 3. By incorporating primary and secondary prevention strategies into occupational health nursing practice, great strides can be made in guiding women to initiate osteoporosis prevention behaviors to promote a more healthy and less restrictive lifestyle in later years.

Female↗
PubMed2004

Distribution of Ochlerotatus togoi along the Pacific coast of Washington.

Before this study, the mosquito Ochlerotatus (Finlaya) togoi (Theobald) had been reported from only 2 locations within the continental United States, both of which were documented in Washington State. This study used active and passive surveillance to determine the current distribution of Oc. togoi along the Pacific Coast of Washington. Results of the study show that small, but stable, populations of Oc. togoi exist in the northern San Juan Island region of Puget Sound. Geological formations in this region are conducive to rock holes and support populations of Oc. togoi. No members of Oc. togoi were found on the southwestern Washington coast, the coast of the Olympic Peninsula, or in the lower Puget Sound.

Animals↗
PubMed2005

Historical demography, selection, and coalescence of mitochondrial and nuclear (genes in Prochilodus species of northern South America.

Fishes of the genus Prochilodus are ecologically and commercially important, ubiquitous constituents of large river biota in South America. Recent ecologic and demographic studies indicate that these fishes exist in large, stable populations with adult census numbers exceeding one million individuals. Abundance data present a stark contrast to very low levels of genetic diversity (theta) and small effective population sizes (Ne) observed in a mitochondrial (mt) DNA dataset obtained for two species, Prochilodus mariae, and its putative sister taxon, Prochilodus rubrotaeniatus. Both species occupy major river drainages (Orinoco, Essequibo, and Negro) of northeastern South America. Disparity between expectations based on current abundance and life history information and observed genetic data in these lineages could result from historical demographic bottlenecks, or alternatively, natural selection (i.e., a mtDNA selective sweep). To ascertain underlying processes that affect mtDNA diversity in these species we compared theta and Ne estimates obtained from two, unlinked nuclear loci (calmodulin intron-4 and elongation factor-1alpha intron-6) using an approach based on coalescent theory. Genetic diversity and Ne estimated from mtDNA and nuclear sequences were uniformly low in P. rubrotaeniatus from the Rio Negro, suggesting that this population has encountered a historical bottleneck. For all P. mariae populations, theta and Ne based on nuclear sequences were comparable to expectations based on current adult census numbers and were significantly greater than mtDNA estimates, suggesting that a selective mtDNA sweep has occurred in this species. Comparative genetic analysis indicates that a suite of evolutionary processes involving historical demography and natural selection have influenced patterns of genetic variation and speciation in this important Neotropical fish group.

Animals↗
PubMed2005

[Effects of glutamate transport inhibitor on organotypic cultured spinal cord slices].

This study was aimed at investigating the effect of glutamate on motor neurons in organotypic cultured spinal cord slices treated by threohydroxyaspartate (THA), an inhibitor of glutamate transporter. The spinal cord cultures were prepared using lumbar spinal cord slices from 8-day-old rat. Various concentration of THA(50 micromol/L,100 micromol/L,500 micromol/L) was added into the culture medium respectively. Ventral alpha-motor neurons survival was evaluated by immunohistochemistry staining monoclonal antibody SMI-32, a nonphosphorylated neurofilament marker, and interneurons in dorsal horn were identified by monoclonal anti-calretinin antibody staining. Lactate dehydrogenase (LDH) level in the culture medium was also measured. The spinal cord slices in the control group could maintain excellent organotypic cellular organization and a stable population of ventral alpha-motor neurons. THA caused a slow dose-dependent loss of alpha-motor neurons and an increase in LDH enzyme activity in the culture medium while dorsal interneurons were less damaged. 100 micromol/L THA resulted in a significant decrease in (alpha-motor neurons after cultured for 4 weeks. On the contrary, the interneurons in the dorsal horn were less affected. It was also observed in patients with amyotrophic lateral sclerosis (ALS). Excellular Glu mainly caused selective alpha-motor neuron death, and motoneurons were more sensitive to glutamate excitotoxicity than sensory neurons in the spinal cord.

Animals↗
PubMed2005

Conservation and development in Amazonian extractive reserves: the case of Alto Juruá.

Extractive reserves constitute an innovative approach to match conservation and development objectives, which were originally envisaged as part of a land struggle by forest dwellers in Brazil. In spite of the idea's popularity and the attempts to apply the concept to different tropical regions, there has been little analysis of the combined conservation and development performance of extractive reserve programs. We present a detailed analysis of deforestation and demographic and socioeconomic changes in Alto Juruá, the first extractive reserve created in Brazil in 1990. Forest cover has remained fairly stable. Population has declined slightly, with some internal displacements. The cash economy base has shifted from the original rubber production to a diversified portfolio of agriculture and livestock, and there has been a dramatic rise in nonagrarian income. We conclude that the Reserve represents a very dynamic setting with positive conservation and development outcomes during its first decade.

Agriculture↗
PubMed2005

[Genetic polymorphism of a pelagic fish species, little Baikal oilfish Comephorus dybowski, deduced from analysis of microsatellite loci].

Intraspecific genetic polymorphism of a Baikal Lake endemic, little Baikal oilfish (Comephorus dybowski Korotneff, 1905), was evaluated based on microsatellite analysis. Six microsatellite loci designed for the European sculpin, Cottus gobio, were used. Each locus was typed using 25 to 35 individuals from each of the Baikal trenches (southern, middle, and northern). Analysis of genetic differentiation (F(ST) and R(ST)) revealed no statistical significant differences between the samples. The data showed that the target species was represented by a single panmictic stable population.

Animals↗
PubMed1992

Prevalence of headache and migrainous headache in Nigerian Africans: a community-based study.

In a door-to-door survey in a Nigerian town with stable population of about twenty thousand, 18,594 subjects were screened with a questionnaire, which involved a complete census, administered by non-doctor, including primary health care personnel. Migrainous headache was diagnosed on the basis of combination of responses to the questionnaire shown in a pilot study validated by neurological examination to have 92% sensitivity and 99% specificity. Crude life time prevalence ratio of at least one episode of headache unspecified was 51 percent (50% in males and 52% in females). The crude prevalence ratio of migrainous headache was 5.3 per 100 (5 per 100 in males and 5.6 per 100 in females), with peak age-specific prevalence ratios in the first decade in both males and females. Migrainous headache was three times as common in females as in males in the second and third decades. Prevalence of migrainous headache in Nigerian Africans appears less than in Caucasians. No social status was at special risk to developing migrainous headache.

Adolescent↗
PubMed1991

Design and compliance of HBV vaccination trial on newborns to prevent hepatocellular carcinoma and 5-year results of its pilot study.

A large-scale, controlled study of universal immunization of newborns against HBV infection has been conducted in the high incidence area of hepatocellular carcinoma, Qidong County of China. This area has a stable population, standardized cancer registration system, and an epidemiological base for measurements of liver cancer prevention by vaccine. Randomization was done on the community level. The vaccination and the control group each will consist of 38,000 children by the end of 1990. It is anticipated that the design will provide high statistical power to detect 50% reduction in the prevalence rate of chronic hepatitis among the vaccinees vs. the controls at 6 to 10 years of age, and 50% reduction in the incidence rate of hepatocellular carcinoma at 35 to 40 years of age. The vaccine used is Hep-B Vax, donated by Merck and Co. through WHO. The vaccine was administered at 0, 1, and 6 months after birth, the dosage of 5 or 2.5 micrograms in the pilot study as used before 1985 and of 5 micrograms dose level during the main study starting from January 1, 1985. About 85% of the cohorts have now entered the protocol. The vaccination coverage during 1984 to 1989 was 98.0% (35,064/35,789). Follow-up of the vaccinees and the age-matched controls at 5 years has exceeded 97%. The cumulative mortality in the vaccinated group up to 1988 was 1.29% (354/27,450). No single death nor serious adverse reaction was found that was associated with vaccination. The use of HBV vaccine at a reduced dose was especially important for the developing countries at the present time in order to achieve widespread immunization. Five-year results of the pilot study of this vaccination project showed that significant protection against HBV infection was achieved with the 5 or 2.5 micrograms per dose regimen plus a booster of 5 micrograms given at 3.5 to 4 years of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Hepatocellular↗
PubMed2006

Atherogenic lipid profiles in rheumatoid arthritis.

AIMS: Rheumatoid arthritis is associated with an excess mortality from cardiovascular disease, and this may be related to an atherogenic lipid profile. We set out to identify whether there was a correlation between disease activity and levels of different lipid fractions in a stable population of patients with rheumatoid arthritis on disease-modifying therapy. METHODS: Patients with rheumatoid arthritis were selected from our database and requested to have inflammatory markers and a fasting lipid profile taken at their next visit for monitoring of their disease modifying therapy. RESULTS: 204 patients were recruited for the study. A statistically significant relationship exists between reduced HDL and elevated CRP (p=0.01) and ESR (p=0.041). Elevated ESR, but not elevated CRP, was associated with raised LDL cholesterol (p=0.014). Fourteen patients (6.8%) were receiving statin therapy and 71 (34.8%) were taking prednisone. Use of prednisone, independent of dose, was associated with elevated triglyceride levels (p=0.041). CONCLUSIONS: This study supports previous work showing that rheumatoid arthritis is associated with an adverse lipid profile. While good disease control is clearly important, we should not neglect management of traditional cardiovascular risk factors.

Adult↗
PubMed1991

The production of a bispecific anti-CEA, anti-hapten (4-amino-phthalate) hybrid-hybridoma.

A standard hybridoma fusion technique was used to produce a monoclonal antibody capable of binding both carcinoembryonic antigen (CEA) and the hapten 4-amino-phthalate. A hypoxanthine-aminopterin-thymidine (HAT) sensitive anti-CEA hybridoma and KLH-phthalate immunized spleen cells were hybridized to yield clones producing bispecific monoclonal antibodies. The desired bispecific antibody was identified using both enzyme-linked immunosorbent assay (ELISA) and radio-immunoassay. The resultant hybrid-hybridoma or "tridoma" was subcloned and expanded to yield a stable population. Bifunctional antibody was then isolated from the various possible recombinants by ion exchange chromatography. This general method may be used to produce bispecific monoclonals against a wide variety of tumor associative antigens and reagents for immunodetection or treatment.

Animals↗
PubMedDate not supplied

[A comparison of the growth of 2 species of Pomacea from the Antilles area useful as an agent to control tropical diseases].

A comparative study was made on the growth of 2 Pomacea species (P. glauca and P. paludosa) of the Caribbean area. The occurrence of ecological differences reflected on the growth parameters is noted. These discrepancies may be influenced by differences in the physical-chemical and environmental status of the localities under study, but a clear-cut ecological difference between both species can be observed. Growth parameters (K and L phi), as well as the growth curves, suggest they are slow-growing species with a long life range. Differently from intermediate hosts, which are fast-growing species with a short life range, Pomacea species may keep stable populations in permanent bodies of water. It means an important advantage as biological control agents.

Animals↗
PubMed1991

[Epidemiology and control of malaria in Suriname].

Malaria is endemic in the interior of Suriname, which is inhabited by descendants of black slaves and Amerindian tribes. Analysis of epidemiological data for the period 1965-1985 reveals that within that area malaria is endemic only in the territory of the Djuka Indians in the Upper Marowijne region. The endemicity may be due in part to the presence of a relatively large and stable population of the local vector, Anopheles darlingi, and also to the Djukas' frequent travels within their own territory. During 1985, transmission occurred year-round in only two of the many villages of the region, and the majority of cases were found in those same villages. Research following outbreaks of malaria in isolated villages in the plains region and the interior showed that the Djukas employed by the governmental services near these villages probably acted as partially immune carriers of the malaria parasites, transporting them from the reservoir to the villages where the outbreaks occurred. Recommendations are being formulated for the prevention and control of malaria in the interior of Suriname.

Black or African American↗
PubMed1991

[Mechanisms of hemolysis under the effects of extreme factors].

It has been shown that the activation of reno-dependence mechanisms of destruction of the low-stable population of erythrocytes was observed following the acute blood loss, the infusion of the phenylhydrazine and uranyl-glycerine solution. These mechanisms have different nature: humoral (increase of hemolytic activity of the blood serum up to 46.6%), autoimmune-cell or vasorenal (increase of the autoplateformation in 1.8 ones, of the activity of the system mononuclear phagocytes on 37.6%).

Acute Disease↗