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PubMed1991

The family in Tanzania.

"The article starts by defining the terms and basic characteristics of the family institution. Then it moves to explain and analyze the changing roles and relationships in the Tanzania context. The article stresses...the impact of the foreign cultures and ideologies. Specifically, the role of family in [the] socialization process has been minimized due to the introduction of formal education. With regard to the demographic variables, it is noted that while death rates might be reduced due to the general improvement of health facilities, birth rates will increase....Polygamy...is [likely] to decrease due to socio-economic reasons like the level of education among the women and the economic difficulties in running large families." A trend toward smaller families is noted. The study is based on the author's recent research in Tanzania.

Africa↗
PubMed1991

Marriage and conjugal roles in Swaziland: persistence and change.

"This paper examines one set of relationships central to the Swazi household--marriage and conjugal roles--and how those relationships have changed over the last half century. Information has been analyzed on such topics as types of marriages contracted, the age at marriage, choice of spouse, attitudes towards and participation in polygyny, the nature of conjugal roles, and the question of divorce. This study has drawn upon a wide range of sources including (1) an analysis of civil records from the office of the District Commissioner in Manzini, Swaziland; (2) data collected previously by other social scientists; and (3) survey data gathered especially for this study. The study concludes that while changes have occurred, many traditional patterns of marriage and family continue to be important in contemporary Swazi society."

Africa↗
PubMed1993

Migration and the life course.

The importance of migration as a biographic event within the life course is asserted, using data for the former Federal Republic of Germany. "The migration process can be described by...various factors like the frequency of moves, the age when changing residence, the distance, the direction, [and] the motives.... Each change of residence has both a retrospective and prospective aspect. Additionally, changes in other biographic processes like marriage or births of children in the familial career or changes in the occupational career directly influence migration decisions. But there are also effects in the opposite direction: the migration process can influence the further development of other biographic processes. Thus, there exist a very complex structure of strong interdependent relationships between the several biographic careers." (SUMMARY IN FRE)

Behavior↗
PubMed1995

[Mexican families in their homeland and in exile].

"The present study takes advantage of the Mexican and American census simultaneity in Spring 1990 to compare the Mexican populations according to their migratory status. The analysis of their composition by age and by sex is completed by an estimation of the undercount of migrants omitted by these statistics.... The fertility of the Mexican immigrants is compared to that of the country of origin and to that of Mexican Americans so as to specify changes induced by the exile. But one of the most interesting mutations deals with the recomposition of the migrant's family in the U.S.: units of residence gain in complexity by the extended integration of relatives or individuals that do not belong to the nuclear family." (SUMMARY IN ENG AND SPA)

Americas↗
PubMed1994

[Economic welfare of Canadian children: changes and implications for social policy].

"This study recommends courses of action within the scope of social policy revision in Canada, aiming to increase funding for children. These recommendations stem from a critical review of guaranteed income programmes and an analysis of the actual economic welfare of children. The authors describe the evolution of the nature of the family in Canada over the past twenty years and of the economic status of children. Their assessments are based on an analysis of cross-sectional micro-level data on income and socio-economic characteristics drawn from a very large sample of Canadian families." (SUMMARY IN ENG AND SPA)

Adolescent↗
PubMed1996

Demographic transition and population aging in Korea.

"This paper describes the process of population aging in conjunction with the demographic transition in [South Korea]. Korea has recently experienced rapid decreases of both mortality and fertility, which have brought about the rapid process of population aging. The speed of...population aging in Korea is projected as one of the fastest in the world. Population aging brings about changing patterns of family composition, especially new trends of living arrangements of the elderly. Since the process of population aging [began] in Korea, the proportion of [those] living alone and [of those] living with spouse only have significantly increased."

Adult↗
PubMed1998

Changing marital and family patterns: a test of the post-modern perspective.

"Four central constructs of the post-modern perspective are extended and tested using secondary analysis of [U.S.] Census data and the NORC General Social Survey: 1972-94 data sets. The modified postmodern themes of: (1) the decline of a single universal family organizational standard, and (2) growing cultural diversity...were supported by examining changes in American family structure, attitudes toward such structural changes, and changing attitudes toward marital and family patterns over the last quarter century. However, little support was found for the greater use of, and reliance on, (3) the mass media. Mixed results were found on the fourth construct, greater variance in, and/or loss of, personal happiness or personal or family life satisfaction."

Americas↗
PubMed1986

An experimental analysis of the origins of somatostatin-like immunoreactivity in the dentate gyrus of the rat.

In previous studies, fibers demonstrating somatostatin-like immunoreactivity were observed in the outer half of the molecular layer of the dentate gyrus in the rat and monkey. They occupy the same region as those of the perforant pathway that originates in the entorhinal cortex. Numerous somatostatin immunoreactive neuronal cell bodies were also observed in the hilar region, though stained axonal profiles could not be followed from these cells into the molecular layer. In the present study, several experimental procedures were employed to determine the origin of the somatostatin-positive fibers in the molecular layer. Transection of the perforant path fibers resulted in such characteristic changes as shrinkage of the molecular layer and sprouting of AChE-positive fibers. There was no apparent decrease, however, in the density of somatostatin-positive fibers. In fact, since the stained fibers occupied a narrower band in the shrunken molecular layer, their density appeared greater. Injections of kainic acid into the hilar region produced a lesion of hilar neurons, including those positive for somatostatin. In the region of cell loss, there was a marked reduction of somatostatin-immunoreactive fibers in the ipsilateral molecular layer, with no detectable changes in the homotopic contralateral molecular layer. The distribution of AChE fibers, which presumably have an extrinsic origin, was not altered by the treatment. In a final series of experiments, the retrograde tracer wheat germ agglutinin-horseradish peroxidase (WGA-HRP) was injected into the hilar region and sections were prepared for the simultaneous demonstration of the tracer and of somatostatin-like immunoreactivity. Somatostatin-positive neurons demonstrating WGA-HRP reaction product were observed primarily in the ipsilateral hilar region, but a few double-labeled cells were also seen in the same area of the contralateral side. These studies indicate that a population of intrinsic neurons located in the polymorphic layer of the dentate gyrus projects to the outer half of the ipsilateral molecular layer. A similar, but very much smaller, projection also extends to the contralateral dentate gyrus. Taken together, these projections appear to account for much of the somatostatin-like immunoreactivity in the molecular layer of the dentate gyrus.

Animals↗
PubMed1988

Age related changes in the human plastron: a roentgenographic and morphologic study.

Characteristic changes that can be demonstrated on roentgenograms occur with increasing age in the plastron (chest plate) of humans. These alterations include progressive ossification in the costal cartilages (located characteristically in the sternal rib end, centrichondrally, and peristernally--often with sex and age distinctive patterns), maturation of the newly formed bone with trabeculation formation, loss of the smooth contour of the costo-manubrial junction, cupping of rib ends, osteoporotic changes, and arthritic changes in the sternal head of the clavicles. The sequence of development of these alterations has been examined by X-ray of 1965 cadavers of 15 years of age or over and correlated with the gross bone and cartilage morphology changes in many cases. This technique allows for age determination within 5 years of real age in 55% of cadavers and within 25% of real age in 95% of all cadavers. The greatest departures from real age are in the over-60-year groups. The same roentgenograms can allow for correct sex prediction in 99% of the population.

Adolescent↗
PubMed1985

Differential sensitivity of human breast cancer cell lines to the growth-inhibitory effects of tamoxifen.

In eight estrogen receptor (ER)-positive breast cancer cell lines (including three sublines of MCF-7) and five ER-negative breast lines, the action of the nonsteroidal antiestrogen, tamoxifen, was studied, and the concentrations of ER and antiestrogen binding site were measured. The concentration of antiestrogen binding site was significantly [P less than 0.005] greater in ER-positive cells [236,600 +/- 29,900 (SE) sites/cell] than in ER-negative cell lines [66,600 +/- 16,800 sites/cell]. In ER-positive cell lines, a cell cycle phase-specific growth-inhibitory effect, 20% inhibitory dose less than 0.1 to 1.0 microM, was seen which was shown for some representative cell lines to be estrogen reversible. Within this group of cell lines, the degree of tamoxifen-induced inhibition of growth correlated with control population doubling time, but not ER or antiestrogen binding site concentration. The changes in cell cycle kinetic parameters characteristic of all ER-positive lines were a decrease in percentage of S-phase cells and a corresponding increase in percentage of G0-G1 cells. In all cell lines, 5 to 12.5 microM tamoxifen caused cytotoxicity, and this was shown to be estrogen-irreversible in 3 representative cell lines; moreover, estradiol synergistically enhanced the cytotoxic effects of tamoxifen under some experimental conditions. The cell cycle effects of tamoxifen in three ER-negative cell lines (Hs0578T, MDA-MB-231, MDA-MB-330) were decreased proportions of G0-G1 cells with an increase in percentages of S and G2+M cells. These results implied that the mechanism of tamoxifen cytotoxicity may differ in ER-positive and ER-negative breast cancer cells. However, although the ER-negative BT-20 line was much less sensitive to tamoxifen than were the ER-positive cells, growth inhibition and cytotoxicity in this line were associated with a slight decrease in percentage of S-phase cells. These results confirm that ER-positive breast cancer cells are more sensitive (4- to greater than 75-fold) than ER-negative breast cells to the growth-inhibitory effects of tamoxifen and demonstrate that, in all ER-positive cells, growth inhibition and cytotoxicity are accompanied by characteristic changes in cell cycle kinetic parameters. In contrast, different mechanisms may be involved in the effects of tamoxifen on different ER-negative cell lines.

Breast Neoplasms↗
PubMed1985

[Effect of hypobaric hypoxia on motor behavior in rats].

Hypobaric hypoxic exposure for 18 h (pO2 8.7 kPa) effects characteristic changes of motoric behaviour in adult rats. We observed a posthypoxic increase of spontaneous locomotion and of open-field activity. 24 h after hypoxic exposure the locomotion stimulated by dopaminergic agonists apomorphine or amphetamine was strengthened. Dopaminergic nuclei showed a different sensitivity to unilaterally applied dopamine after hypoxic exposure. Rotational behaviour was facilitated in the nucleus accumbens but significantly decreased in the substantia nigra. In the nucleus caudatoputamen we could not prove changes in comparison to controls. These results indicate that central dopaminergic processes are influenced by hypobaric hypoxic exposure. Besides the sensitization of dopaminergic receptor populations these changes of motoric behaviour may be connected with interactions between different transmitter systems or displacement of central regulation systems.

Amphetamine↗
PubMed1994

[Comparison of four different methods for respiratory determination of the anaerobic threshold in normal people, and heart- and lung patients].

We analyzed 128 cardiopulmonary exercise tests (CPX), performed in normal subjects (n = 31), in patients with coronary artery disease (n = 41), with chronic heart failure before (n = 14) and after (n = 14) application of oral PDE-inhibitors and in patients with HIV-infection on a bicycle-ergometer in semi-supine position using a ramp-program (dependent on study-population with 15, 20 or 35 Watt/min increases) with respect to the ability to determine the respiratory anaerobic threshold non-invasively, using the main criteria described by Wasserman et al.: the V-slope-method according to Beaver, the increase of the ventilatory equivalent for O2 (VE/VO2), the increase of the end-tidal PO2 (PETO2) and the increase of the respiratory quotient (RQ) during exercise. In the different study-populations we calculated the detection rates of the AT for each criteria separately. The typical changes in the end-tidal PO2 (124/128 = 96.9%) and the V-slope-method (119/128 = 92.9%) were the most reliable parameters to detect the anaerobic threshold. The characteristic changes of the ventilatory equivalent for O2 (VE/VO2) and of the respiratory quotient (RQ) we found in 100/128 (= 78.1%) and in 107/128 (= 83.6%) of the tests respectively. 86/128 tests (67.2%) showed typical changes in all four mentioned criteria. In another 24/128 tests (19.8%) three of four criteria were fulfilled. Therefore, our investigations showed that in 110/128 cases (85.9%) the AT could be determined by typical changes by means of at least three of the four described parameters. In 15/128 (11.7%) tests only two of four criteria were fulfilled.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaerobic Threshold↗
PubMed1993

Multivesicular bodies in HEp-2 cells are maturing endosomes.

Conventional fluorescence microscopy of fixed HEp-2 cells as well as video microscopy of living cells incubated with transferrin-Texas Red (Tf-TxR) for < 60 min revealed distinct punctuate endosomal structures. Quantitative ultrastructural analysis using horseradish peroxidase (HRP) and cationized gold as tracers showed that spherical multivesicular bodies (MVBs) were the predominant endocytic compartments in HEp-2 cells and that MVBs within 60 to 90 min matured into lysosomes still containing internal vesicles. The number of labeled MVBs increased continuously from 2.5 min to 30 min of tracer incubation. However, when the cells were pulsed for 5 min followed by 10 or 25 min chases, the number of labeled MVBs corresponded to that obtained after 5 min of continuous incubation. The diameter of labeled MVBs was largely constant with time, but the number of internal MVB vesicles increased. Thus, early or newly formed MVBs contained few internal vesicles, whereas late MVBs, that is to say, MVBs that have existed for some period of time, contained numerous internal vesicles, and finally a mixture of membranous material or myelin figures and vesicles. It is thus in principle possible to distinguish between early and late MVBs in HEp-2 cells on the basis of morphology. However, the difference in number of internal vesicles applies only to the entire MVB population; after only 2.5 to 5 min of incubation, MVBs with numerous internal vesicles could also be reached by internalized tracer. Concomitant with the gradual changes in morphology, the MVBs also showed a characteristic change in content of marker proteins as detected by immunogold labeling on ultracryosections. Hence, early MVBs with relatively few internal vesicles and typically reached by internalized tracers within 5 min contained transferrin receptors (TfRs). By contrast, MVBs with many internal vesicles and labeled after 60 min of incubation contained mannose-phosphate receptors (MPRs), and the MVBs with distinct membranous material or myelin figures in addition to the internal vesicles were enriched in the lysosome membrane protein lamp-1. Thus, there seems to be a gradual maturation of MVBs in HEp-2 cells.

Carcinoma, Squamous Cell↗