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PubMedDate not supplied

[Family planning].

According to the fact that a great majority of women have expressed their wish to have only two children, two main questions have arised: what are the means that women use to limit their family size and what are the acceptable measures which the society can undertake to avoid further decline of crude birth rate in order to attain a stable population. Except for Kosovo and Macedonia, namely, in all other parts of Yugoslavia depopulating trends are present. Adequate data about contraceptive prevalence are not available, and according to some partial data, even among the women wanting no additional children, the percent of those planning no use of contraception is as high as 17.3 and further 21.2% are planning to rely on less effective contraceptive methods. The result of this situation is a relatively high number of induced abortions in Croatia 1989: 43227 or 77.7 per 100 live births). To improve this unfavourable situation, medical profession has to promote a wider use of contraception in general, particularly with more effective methods. Unfavoured decline of crude birth rate could be corrected, however, only through complex activities of long duration in order to achieve thorough improvement of the standard of living. With these improved living conditions more women would, most probably, want to have more than two children, thus avoiding the present depopulating trends in some parts of the country. On the other hand, any restriction of legal rights and availability of fertility regulation methods would be fully anachronistic and therefore unacceptable, since the only predictable result would be the increase of illegal abortions with all the well-known health risks and life-threatening conditions.

Contraception↗

PubMed1990

[The mentally retarded in the local community--occurrence, causes, medical treatment and follow-up].

An epidemiological study of mentally retarded persons in a Norwegian municipality was carried out in order to collect data about prevalence, causes, medical treatment and follow-up. The number of mentally retarded was found to be twice the average for the country as a whole. The causes of mental retardation indicated that this was due to a low degree of urbanization--a stable population, larger families, more births at home and long distance from hospital. The survey revealed that medical care had been seriously neglected. Several patients had never been given a diagnosis, and the number of contacts with a doctor for any reason was far below the average for the rest of the local population. Several were found to have unknown impaired vision and hearing, and many were being inadequately treated for common diseases like migraine, myalgia, stomach pain, diarrhoea etc. The neglect was worse among those living at home than among those living in the institutions for the mentally retarded.

Community Mental Health Services↗

PubMed1990

The epidemiology of primary biliary cirrhosis in north-east England: an increasingly common disease?

The reported incidence and prevalence of primary biliary cirrhosis has risen in the past 10 years in Northern Europe. In order to determine whether this is a genuine increase in the disease or an apparent increase due to increased awareness of physicians and more ready diagnosis, we have carried out a comprehensive epidemiological study of primary biliary cirrhosis. All possible cases from 1965-1987 were examined using the best case finding methods available. In a relatively stable population of about 1.92 million we identified 471 patients with 'possible' primary biliary cirrhosis and 347 with a definite, histologically confirmed, diagnosis. Prevalence rose from 18/1,000,000 in 1976 to 128.5/1,000,000 in 1987 (276/1,000,000 in women greater than 18 years). Increased awareness and availability of interested physicians seemed to be important contributing factors to the rise in prevalence. No important geographical clustering of cases was noted.

Adult↗

PubMedDate not supplied

[Circulation of the virus of hemorrhagic fever with renal syndrome among small mammals in the territory of the USSR].

Over 55,000 small mammals of 72 species trapped in 62 administrative territories practically in all landscape-geographical zones of the USSR were examined in 1980-1985. The use of current laboratory methods demonstrated a wide spread of HFRS virus in the territory of this country, involvement in the epizootic process of most species of forest and steppe murine rodents and insectivora. In each landscape zone, the main carriers of the HFRS agent were established, represented, as a rule, by the basic species having a high and stable population density.

Animals↗

PubMed1988

Regulation of IgA differentiation in CH12LX B cells by lymphokines. IL-4 induces membrane IgM-positive CH12LX cells to express membrane IgA and IL-5 induces membrane IgA-positive CH12LX cells to secrete IgA.

In these studies we utilized the Ag (SRBC)-reactive B cell line CH12LX to study isotype switching. CH12LX cells are a stable population of B cells mainly bearing membrane IgM (mIgM) (98 to 99%) with a small population of B cells bearing membrane IgA (mIgA) (1 to 2%). LPS induced a 5- to 10-fold increase in the secretion of both Ig, whereas a lymphokine-rich supernatant of D10 T cells induced a greater increase in the secretion of IgA than IgM. Analysis of the latter effect with recombinant lymphokines disclosed that rIL-4 induced an increase in the number of mIgA+ cells (6 to 15%) with minimal effect on IgA secretion, whereas IL-5 induced increased IgA secretion but had no effect on mIgA expression. The addition of both lymphokines induced increased mIgA expression and IgA secretion. No effect on mIgA expression or IgA secretion was seen with other lymphokines, including IL-1, IL-2, IL-3, IL-6, GM-CSF, and IFN-gamma. The rIL-4 effect on CH12LX cells represents true differentiation rather than selective proliferation for the following reasons: first, subclones of CH12LX cells respond to IL-4-containing T cell supernatant in the same fashion as the original cell line; second, culture of CH12LX cells with IL-4 causes the appearance of large numbers of dual-bearing mIgM/mIgA cells as well as mIgA+ cells and a dual-bearing mIgM/mIgA line was obtained by cloning CH12LX after stimulation with an IL-4-containing supernatant; third, sorted mIgA+ and mIgA- CH12LX cells had similar rates of proliferation in the presence or absence of IL-4. In further studies, it was found that IL-5 causes IgA secretion by mIgA+ but not mIgA- CH12LX cells indicating that it is acting as a post-isotype switch differentiation factor. These studies are consistent with the view that IL-4 and IL-5 act in a sequential fashion to induce IgA expression and secretion in CH12LX cells, IL-4 inducing differentiation of mIgM+ cells to mIgA+ cells and IL-5 enhancing the IgA secretion by the resulting mIgA-bearing cells.

Animals↗

PubMed1989

A review of the histology, ultrastructure, immunohistology, and molecular biology of extra-adrenal paragangliomas.

This review summarizes our understanding of extra-adrenal paragangliomas, a subject that has evolved considerably during the past several years. Our object was to review the anatomical, histologic, and biological features of normal and neoplastic glands, with emphasis on immunohistologic studies, and briefly discuss the potential application of nucleic acid hybridization. Since it is difficult to predict clinical outcome for patients with paragangliomas, we have emphasized the differences between benign and malignant paragangliomas, concentrating on recent results obtained using immunohistologic techniques. These studies have emphasized the critical importance of the identification, by immunohistologic means, of two distinct cell populations, chief cells (type I) and sustentacular cells (type II). The relationship between these two cell populations, stable in normal glands and benign tumors, is progressively lost in tumors of increasing degrees of malignancy, sustentacular cells being absent from the most progressively metastasizing paragangliomas.

Adrenal Gland Neoplasms↗

PubMed1988

Constant isotype pattern of anti-dsDNA antibodies in patients with systemic lupus erythematosus.

The isotype profile, particularly emphasizing IgG subclass distribution, of dsDNA antibodies in patients with systemic lupus erythematosus was evaluated using an especially adapted ELISA technique. Anti-dsDNA antibodies were quantified with class-specific antisera and subclass-specific monoclonal antibodies. IgG subclass specificity was proven with 20 myeloma proteins differing in light chains and allotypes. The standardization with myeloma proteins proved to be useful and reliable. Results from more than 100 anti-dsDNA positive sera from SLE patients showed specific antibodies within the three subclasses (IgG1: 52-100%, IgG2: 0-39%, IgG3: 0-48%). IgG4 was not detected in significant amounts. No correlation to the subclass distribution of total IgG was found. Each patients' serum displayed an individual isotype pattern that remained constant in longitudinal studies, independent of anti-dsDNA titre fluctuations. These results suggest a stable population of autoreactive clones in the progress of the disease.

Antibodies, Antinuclear↗

PubMed1988

Nature and fate of proliferative cells in the hippocampal dentate gyrus during the life span of the rhesus monkey.

The nature of proliferative cells in the subgranular zone (SGZ) of the hippocampal region and the fate of their progeny was analyzed by 3H-thymidine (3H-TdR) autoradiography combined with immunocytochemistry at the light and electron microscopic levels in 18 rhesus monkeys ranging in age from late gestation to 17 years. Our analysis indicates that, during the last quarter of gestation and the first 3 postnatal months, the SGZ produces both glial and neuronal cells. These 2 major classes of cells originate from the 2 precursor lines and, following their mitotic division, migrate to the granular layer. During the juvenile period (4-6 months of age), neuronal production tapers off and most postmitotic cells remaining within the SGZ differentiate into glial elements. In postpubertal animals (3 years and older), the 3H-TdR-labeled cells in the dentate gyrus belong to several non-neuronal classes. The largest group was immunoreactive to the glial fibrillary acidic protein (GFAP) at both the light and electron microscopic levels, indicating their astrocytic nature. The remaining 3H-TdR-labeled, GFAP-negative cells had ultra-structural characteristics of either microglia, oligodendroglia, or their progenitory stem cells. Therefore, there is a continuing addition and/or turnover of the glial cells in the dentate gyrus of sexually mature monkeys, but, in contrast to the massive neurogenesis reported in adult rodents, the production of new neurons could not be detected after puberty. The significance of a stable population of neurons in the hippocampal formation of mature primates is discussed in relation to its possible function in memory.

Aging↗

PubMed1986

Energy dependence of contraction band formation in perfused hearts and isolated adult myocytes.

Aggregation of sarcomeres into contraction bands is a prominent feature of the oxygen paradox, the calcium paradox, and caffeine injury to calcium-free perfused hearts. For investigation of the mechanism of contraction banding, it was necessary to devise a method of evaluating the degree of sarcomere contraction and to define objectively a contraction band. Hearts with mechanical detachment of cells caused by hypocalcemic perfusion and isolated myocytes both allow unrestrained contracture of cells and permit direct optical measurements to quantitate the degree of cell contracture. With the use of the calcium paradox as a model of contraction band necrosis, it was found that cells with lengths of less than 37.3 mu could be considered as containing contraction bands. It was found that the mitochondrial inhibitors cyanide and amytal, as well as the uncoupler 2,4-dinitrophenol, allowed cell contracture but inhibited hypercontracture of sarcomeres into contraction bands during both the calcium paradox and caffeine injury to perfused hearts. However, when 2mM adenosine triphosphate (ATP) was included in the perfusion media, contraction band formation occurred despite the continued presence of cyanide or amytal. In isolated myocyte preparations the addition of the glycolytic inhibitor iodoacetate (IAA, 5 mM) and the mitochondrial inhibitor amytal (3 mM) caused relaxed rod-shaped cells (length/width ratio greater than 3:1) to contract into a stable population of square-shaped forms (length/width ratio less than 3:1), indicating an abrupt and severe decline in cellular ATP levels. Removal of amytal from the incubation medium in the presence of IAA produced a significant conversion of square-shaped cells into round-shaped cells containing contraction bands. Either IAA alone or amytal alone resulted in a mixed population of square and round cells. The results indicate that ATP is required for the formation of contraction bands in intact hearts and for the rounding of isolated myocytes. Formation of contraction bands appears to be an energy-dependent process requiring ATP.

2,4-Dinitrophenol↗

PubMed1985

The self-association of human apolipoprotein A-IV. Evidence for an in vivo circulating dimeric form.

We have investigated the self-association properties of human apolipoprotein A-IV using several complementary physical techniques. Sedimentation equilibrium analysis demonstrated that human apolipoprotein A-IV formed oligomeric species in aqueous solution at physiologic pH. Computer analysis established that the best model of self-association is a monomer-dimer-tetramer scheme, with an unusually large monomer-dimer association constant of 2.9 X 10(5) liters/mol. Fluorescence spectroscopy and electrophoretic analysis demonstrated that the rate of monomer-oligomer interconversion is sufficiently slow that a stable population of dimeric protein exists in solution, even at low total protein concentrations, and that the extent of dimerization is minimally influenced by pH. Moreover, these techniques established that the dissociation of oligomeric forms and the unfolding of the monomeric form are discrete and sequential events. In experiments where apolipoprotein A-IV was incubated with human high density lipoproteins, fractionated by gradient gel electrophoresis, and localized by immunoblotting, dimer formation occurred, but very little binding to lipoproteins was observed. Immunoblots of human serum fractionated on acrylamide gradient gels and isopycnic density gradients demonstrated an apolipoprotein A-IV band of size and density consistent with a circulating dimeric form, unassociated with lipid. We conclude that human apolipoprotein A-IV undergoes high affinity self-association in aqueous solutions, and that such self-association likely occurs in vivo. Self-association may thus be important in determining the biologic behavior of human apolipoprotein A-IV by influencing both the kinetics and distribution of its association with plasma lipoproteins.

Apolipoproteins A↗

PubMed1986

Current concepts in acromegaly: etiology, diagnosis, and treatment.

Acromegaly is an insidious disorder of somatic growth and metabolic derangements that results from the chronic hypersecretion of growth hormone (GH) in the adult. While its precise incidence in this country remains undocumented, a recent epidemiologic study of a stable population of 3.1 million in England suggested an annual incidence of approximately 0.3 cases per 100,000, with a prevalence of diagnosed cases approaching 4 per 100,000. In the majority of cases the diagnosis, once considered, is not difficult, although in recent years the spectrum of possible etiologies has been considerably broadened. As with most diseases, the problems of diagnosis arise with the more subtle or less classical examples of the syndrome. This review will briefly discuss the possible etiologies and clinical presentation of acromegaly, and then focus on the diagnosis and management of this potentially devastating disease.

Acromegaly↗

PubMed1985

Myelination determines the caliber of dorsal root ganglion neurons in culture.

In order to understand the relationship of supporting cells to the differentiation of neurons in culture, we have used morphometry to study myelination of dorsal root ganglion (DRG) neurons by central or peripheral supporting cells. Dissociated DRG cultures from 15-day rat embryos, free of Schwann cells and fibroblasts, were prepared, and supporting cells were added from spinal cord or DRG; myelination commenced after 2 weeks. Control cultures received no supporting cells. At 7, 14, and 24 days, a total of 22 cultures were processed for electron microscopy. Three fascicles from defined points were sampled from each culture. In cultures containing glial cells, smaller fibers (p less than 0.001) were myelinated (mean of median diameter, 1.13 +/- 0.13 (SD) micron) than in cultures containing Schwann cells (1.67 +/- 0.17 micron), although there was no difference (p greater than 0.1) in the degree of myelination expressed as number of myelin lamellae/fiber. A new finding concerned the relationship of axonal diameter to the presence or absence of myelinating cells. In control cultures without supporting cells or in areas where supporting cells were absent, the range of neurite diameter (0.05 to 1.25 micron) and the median diameter (mean of median, 0.24 +/- 0.03 micron) were similar at different times (7, 14, and 24 days), demonstrating a stable population of neurite diameters throughout the period. In myelinated fascicles, a different distribution of neurite diameters was present. Myelinated neurites had a greater median diameter (measured to inner border of myelin) and a different range of fiber diameters compared to bare neurites. For Schwann cells, this range was 0.7 to 3.4 micron, and the mean of median diameters was 1.67 +/- 0.17 micron; for glial cells, the range was 0.6 to 2.4 micron, and the mean of median diameters 1.13 +/- 0.13 micron. Differences between myelinated and bare fibers were all highly significant (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1985

Prevention of preterm births: a perinatal study in Haguenau, France.

A reduction in preterm births has been observed in Haguenau (Eastern France) during a 12-year intervention study with a program for prevention of preterm deliveries. The Perinatal Study of Haguenau was an observation tool used in a stable population, and it allowed measurement of the way women have progressively responded to the new proposals in prenatal care. It also allowed measurement of the results of the interventions: low birth weight (less than 2,500 g) and preterm birth rates (less than 37 weeks of gestation) among single live births. The total duration of the study was divided into three periods of four years (1971 through 1974, 1975 through 1978, and 1979 through 1982), for which the numbers of single live births are 5,763, 4,957, and 5,919, respectively. For the same periods, the low-birth-weight rates, 4.6%, 4.0%, and 3.8%, respectively, showed a significant decrease (P less than .001). Following a similar pattern, the rates of preterm birth were 5.4%, 4.1%, and 3.7% (a significant reduction with P less than .001). These improvements in pregnancy outcome do not disappear after standardization of mother's age, high blood pressure, or social class distribution. These findings, which concur with the results of others, enhance the hypothesis of a direct relationship between a prevention program and a reduction in preterm birth rates.

Birth Weight↗

PubMed1979

Juvenile amyotrophic lateral sclerosis. A report of two cases in a single family.

This paper presents two juvenile cases of familial amyotrophic lateral sclerosis. They are the first and fourth child in a family with seven children from the eastern part of Finland. All seven children, as well as the parents, were examined by our group. In the first case the disease showed a rather mild course, while in the second a noticeable progression was observed even during a period of 10 months. The patients come from a rural area with a stable population and low immigration, which may favor an enrichment of certain genes and therefore support the possible hereditary basis for the disease.

Adolescent↗

PubMed1967

The relationship between the tick-borne encephalitis virus and the ticks and mammals of the Tribec mountain range.

The basic problem in the study of tick-borne virus diseases is to establish where the virus is maintained in nature. In general, this focus will be found where there are large and relatively stable populations of ticks, small rodents and insectivores. In the Tribec region the principal vector of tick-borne encephalitis (TBE) is Ixodes ricinus, although other species can circulate the virus under suitable conditions. The virus can persist during winter either in starving nymphs or adults or in non-starving larvae or nymphs. It can also persist in hibernating mammals, but this is a less important mechanism. Among the mammals, the insectivores (hedgehogs, shrews and moles) and certain rodents are hosts of ticks and reservoirs of TBE virus of great importance. During spring, game and farm animals play an important role and birds are important hosts when the number of small mammals is low. Thus the survival of TBE virus depends on a complex interaction of varying populations of tick vectors and vertebrate hosts that occur in different habitats influenced by different environmental conditions.

Animals↗

PubMed1983

Measuring the tightness of a marriage squeeze.

The "marriage squeeze," or the effect on marriage of an imbalance between the numbers of males and females, has been seen as having a great influence on contemporary marriage behavior. Nonetheless, the literature does not contain a clear definition of exactly what a marriage squeeze is and contains few quantitative estimates of its impact on marriage. The present article provides a precise definition of the marriage squeeze in equation (2), and applies it to measure both artificially produced marriage squeezes in two-sex nuptiality stable populations and the experience of the United States during the period 1950-1990. The marriage squeeze is shown to be capable of producing significant changes in both the level and distribution of marriage, and it appears to be having such an impact in some contemporary Third World societies. For developed countries in general and for the United States in particular, the marriage squeeze exerts little influence on the level of marriage but has a considerable effect on the distribution of marriages. The U.S. age-sex composition of the year 1978, compared to that of the year 1951, is shown to imply a 0.54 year decrease in the male mean age at marriage and a 0.53 year increase in the female mean age at marriage, as well as an 18 percent reduction in the variance of the male ages at marriage and a 33 percent increase in the variance of the female ages. The social and economic implications of such changes have yet to be fully explored.

Adolescent↗

PubMed1984

Abdominal aortic aneurysms: the changing natural history.

The records of all patients with abdominal aortic aneurysms (AAAs) in a Midwest city with a stable population over a 30-year period were reviewed. There were 296 patients (196 men and 100 women) for an incidence of 21.1 aneurysms/100,000 person-years. The median age at diagnosis was 69 years for men and 78 years for women. Seventy-eight percent of patients were asymptomatic at the time of diagnosis; their aneurysms were incidental findings. Rupture occurred in 60 patients (20.3%). Thirty-six patients (12.2%) had rupture of the aneurysm as the presenting complication. For previously diagnosed aneurysms that subsequently ruptured, the average period from diagnosis to rupture was 48.7 months. Rupture occurred in only two aneurysms smaller than 5 cm. The overall mortality rate from rupture was 15.5%. Evaluation of data (including autopsy reports) by decade revealed an absolute increase in the incidence of AAAs in the population under study. More aneurysms of all sizes occurred from 1971 to 1980 than in the previous two decades combined. Although ultrasound examination has increased the detection of small aneurysms, the incidence of aneurysms 7 cm or larger at the time of diagnosis has also increased; the frequency of rupture was greatest in the last decade. To compare the data of the population-based study with the statistics for patients seen in a referral practice, the records of 616 patients from a referral population were also reviewed. In the referral population the ratio of men to women was 5:1, and the age at diagnosis was lower for both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1983

An integrated system for demographic estimation from two age distributions.

This paper presents a simple method for estimating a birth rate and a level of mortality for an intercensal period. The birth rate is estimated from the intercept of a line fitted to data and the level of mortality from the slope of that line. The formula that is developed is based upon a recent generalization of stable population relations. An estimate of childhood mortality level is an optional but significant piece of additional input. An important by-product of the procedure is an estimate of the true age distribution.

Adolescent↗