The effects of family planning effort and development on fertility: an intervening variables framework.
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Contraception↗
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Analysis of hair samples of mummies from Semma South (Sudanese Nubia).
Hair samples from 76 burials at Semna South (Sudanese Nubia) were examined using a variety of techniques. Electrophoresis and fluorescence microscopy indicated some oxidation of the cuticule and keratin protein had taken place. However, the cuticular structure and the lack of fluorescence of the cortex indicate that the low humidity and non-alkaline conditions preserved the physical and chemical properties of the hair well. Pigmentation, even allowing for oxidation of melanin, showed a higher proportion of lighter samples than is currently associated with the Nubian area. Hair form analysis showed medium diameter and scale count; the curling variables were intermediate between European and African samples. There was a high ratio of maximum to minimum curvature (a measure of irregularity), approached only by Melanesian samples. Meroitic and X-group burial types were not statistically significantly different (largely due to sample sizes), but the X-group, especially males, showed more African elements than the Meroitic in the curling variables. Principal components analysis showed the Semna sample to be significantly different from seven populations examined earlier.
Anthropology, Physical↗
The importance of process variables analysis in the assessment of long-term oxygen therapy by concentrator.
The aim of the present study was to evaluate process variables and intermediate outcomes involved in long-term oxygen therapy (LTOT) by concentrator with the purpose of identifying which of those factors would be the most influential in the final health outcome of the therapy. A cross-sectional survey was carried out on a random sample of 111 patients receiving LTOT by concentrator in Catalonia (Spain). Patients were interviewed and assessed at home by a trained physician, and the variables collected were arterial oxygen saturation, performance of the concentrators, and patient compliance. Sixty-two patients participated in the study. Overall, LTOT was appropriately prescribed in 36 patients, of whom only 29 were able to correct their level of hypoxaemia. Patient compliance with treatment was considered adequate in 19 of those 29 patients. Thus, only 19 of 62 patients (31%) fulfilled those criteria needed to achieve the expected clinical benefits. Strategies for improving the effectiveness of medical interventions or technologies ought to consider those factors of the therapeutic process which might influence the expected health outcomes in a specific health-care context.
Aged↗
Determinants of birth intervals in Kerala: an application of Cox's hazard model.
"The present study is an attempt to delineate the differences in the patterns and determinants of birth intervals which appear highly relevant in a transitional population such as Kerala [India]. In this country two comparable surveys, with a period difference of 20 years, were conducted. The study tries to estimate the effects of socio-economic, demographic and proximate variables using Cox's proportional hazard model. For the former data-set, socio-economic variables have [a] significant effect on birth intervals, while for the latter data proximate variables are the significant determinants of birth intervals." (SUMMARY IN ITA AND FRE)
Asia↗
Distribution of cytokeratin polypeptides in syringomas. An immunohistochemical study on paraffin-embedded material.
The distribution of cytokeratin (CK) polypeptides expressed in syringomas (12 cases) was compared with that in normal eccrine sweat ducts using immunohistochemical techniques on paraffin-embedded tissue. Intradermal and intraepidermal segments of the eccrine duct showed reactivity with an antibody to CK1/5/10/11 in all cell layers, whereas CK19 expression was restricted to the luminal cell layer. CK14 was expressed in all cells of the eccrine duct except for the peripheral cells of the intraepidermal duct. Expression of CK5/6 was seen in the basal cells of the dermal duct and of the lower intraepidermal duct (sweat duct ridge) exclusively. Reactivity with an antibody to CK1 was found in the intermediate cells of the uppermost part of the eccrine dermal duct. In addition, this antibody gave a strong staining of the peripheral cells of the intraepidermal duct, leaving basal cells of the sweat duct ridge and luminal cells unstained. In syringoma, CK distribution was essentially comparable with that found in the uppermost part of the dermal duct and in the sweat duct ridge. Namely, ductal luminal cells expressed CK1/5/10/11, CK19, and variably CK14. Intermediate cells of ductal structures and solid nests were homogeneously stained by antibodies to CK1 and CK1/5/10/11, whereas CK14 was expressed heterogeneously. The basal or outermost layer of ductal structures and solid nests was reactive with antibodies to CK1/5/10/11, CK5/6, and CK14. With regard to CK expression, the results indicate that syringoma represents a tumor differentiating toward both the uppermost part of the dermal duct and the lower intraepidermal duct (sweat duct ridge) of the eccrine sweat gland.
Adenoma↗
Changes in QUS and BMD measurements with antiresorptive therapy: a two-year longitudinal study.
There is lack of consensus on whether quantitative ultrasound (QUS) measurements can be used to monitor response to therapy. The aim of this 2-year longitudinal study was to assess whether calcaneal QUS measurement variables respond to antiresorptive therapy and whether these measurements display adequate long-term precision to be useful for monitoring purposes. The study population consisted of 195 postmenopausal women divided into three groups: Group 1: 39 women treated with antiresorptive therapy who commenced treatment at baseline; Group 2: 25 women treated with antiresorptive therapy who had been on treatment for at least 2 years at baseline; Group 3: 131 women who did not taken estrogen, bisphosphonates, or calcium during the 2-year study period. Subjects had baseline and 12 and 24 months follow-up BMD measurements at the lumbar spine (LS), femoral neck (FN), and total hip (THIP) and calcaneal QUS measurements of broadband ultrasound attenuation (BUA) and speed of sound (SOS). BUA and SOS were combined to provide an estimate of heel BMD (Est heel BMD). For women in Group 1, all BMD and QUS measurement variables increased significantly from baseline after 2 years of treatment. For women in Group 2, only THIP BMD and BUA increased significantly after 2 years and the changes were less than those observed in Group 1 women. The overall treatment effect for each measurement variable, defined as the difference in the mean absolute changes between Groups I and 3 after 2 years, was 0.08, 0.03, and 0.04 g/cm2 for LS, FN, and THIP BMD, and for BUA, SOS, and Est heel BMD it was 5.8 dB/MHz, 13.1 m/sec, and 0.05 g/cm2, respectively. When the overall treatment effect was expressed in T-score units, the effect was greatest for LS BMD (0.65 T-score units) and lowest for FN BMD (0.31 T-score units). QUS measurement variables yielded intermediate values of 0.43- 0.52 T-score units. The average least significant change (LSC) was 0.38 T-score units for BMD measurements, whereas the LSC for QUS measurements was three times greater at approximately 1.20 T-score units. Ninety-four percent of the women in Group 1 showed changes in LS BMD that exceeded the LSC after two years, while the percentage was lower for the other measurement variables ranging from approximately 6% for FN BMD, SOS and Est heel BMD to 50% for THIP BMD. A lower percentage of women in Groups 2 and 3 displayed changes that exceeded the LSC for both BMD and QUS measurement variables. Changes in all QUS variables were significantly correlated with changes in LS BMD, with correlation coefficients ranging from 0.26 to 0.40. In conclusion, calcaneal QUS measurement variables were found to show a highly significant response to antiresorptive therapy. However, the precision of QUS measurements was not good enough to allow QUS to be used for monitoring response to treatment. Future improvements in the precision of calcaneal QUS measurements are required to increase the utility of QUS for monitoring purposes.
Bone Density↗
[Grouping of countries according to basic and economic indicators].
"Countries are grouped according to a collection of basic and economic indicators published by UNICEF, in 1990. Two multivariate statistical methods were used: Principal Component Analysis and Cluster Analysis. The study [covers] 36 countries of the Americas, Europe (including the USSR), the Middle East, Asia and the other continents; they were chosen to include countries having complete information (for the 16 variables used) and in the most varied stages of development. The first principal component was interpreted as a measure of the degree of development...with emphasis on the position occupied by Brazil (13th place among the 25 American countries). In general, the most discriminative variables were the mortality rates of infants and children under five, and life expectancy...." (SUMMARY IN ENG)
Americas↗
Metabolic capacity and myosin expression in single muscle fibres of the garter snake.
1. The transversus abdominis muscle of the garter snake contains fibres of three types: tonic (T), slower twitch (S) and faster twitch (F). Fibre types can be determined by anatomical criteria in living preparations. Individual fibres identified as T, S or F were excised from the muscle and subdivided for two types of biochemical examination. Enzymes of energy metabolism were assayed using quantitative microfluorometric methods. Myosin heavy chain composition was determined by gel electrophoresis. In separate experiments, twitch time-to-peaks of F and S fibres were measured to assess the range of contraction times present within the muscle's twitch fibre population. 2. Metabolic subgroups of fibres were delineated by the relative activities of adenylokinase (AK), lactate dehydrogenase (LDH) and beta-hydroxyacyl-CoA-dehydrogenase (beta OAC). The metabolic subgroups corresponded to the anatomical fibre types. Type F fibres had high levels of enzymes associated with glycolytic (LDH) and high-energy phosphate (AK) metabolism. Type T fibres had high levels of the oxidative enzyme beta OAC. Type S fibres had both types of enzyme activity in intermediate and variable amounts. 3. Three myosin heavy chain isoforms were present in the muscle. Type F and type T fibres each expressed a single isoform, denoted F and T respectively. Type S fibres expressed significant quantities of two isoforms: an isoform unique to this fibre type (denoted S) and the F isoform. 4. Electrophoretic mobility and antibody reactivity of the F myosin heavy chain isoform resembled that of mammalian fast-twitch myosin. By the same criteria, the T isoform resembled mammalian slow-twitch myosin. The S isoform exhibited intermediate characteristics: its antibody reactivity was similar to mammalian fast-twitch myosin, but its electrophoretic mobility was that of mammalian slow-twitch myosin. 5. Based on whole-muscle analysis, two myosin alkali light chains, denoted ALC1 and ALC2, and one myosin regulatory light chain were present. Gel patterns suggested that ALC1 and ALC2 exist as both homodimers and heterodimers. 6. The population of type S fibres within a given muscle exhibited a much wider range of twitch contraction times than did the population of type F fibres. Diversity of contractile properties among type S fibres may result, in part, from differential co-expression of two myosin heavy chain isoforms, together with highly variable ratios of enzymes from two major metabolic pathways. 7. The clear biochemical distinction among fibre types indicates that each type possesses a unique and limited range of physiological properties.(ABSTRACT TRUNCATED AT 400 WORDS)
Animals↗
Migrant stock vs. lagged migrant flow as a determinant of migrant settlement. A comment on Anjomani and Hariri.
The author comments on a study by Ardeshir Anjomani and Vida Hariri "of United States interstate migration which explicitly incorporates so-called 'flow diversion' and 'flow creation' effects. Their discussion and evaluation of the model, however, are marred by several factors. This paper contrasts the roles of migrant stock and lagged migration in migration analysis and then addresses (a) the problems encountered when the 'family-friends' effect is proxied with measures of lagged migrant flows, (b) the problem of using a two-period lagged value of earlier migrant flow as an explanatory variable, and (c) this paper suggests an alternative method of correcting the Anjomani-Hariri model's problems with multicollinearity."
Americas↗
Assimilation and stratification in the homeownership patterns of racial and ethnic groups.
"This study investigates homeownership differences among twelve racial/ethnic groups using the [U.S.] Public Use Sample data (PUMS) of the 1980 census.... The study identifies a number of differences among non-Hispanic whites, blacks, American Indians, and Asian and Hispanic groups in access to homeownership.... For every group there is a strong correspondence between homeownership and various individual-level factors: age, household composition, socioeconomic position and language acculturation. The observed differences in ownership are substantially attenuated when group differences in some of these variables are controlled."
Acculturation↗
Generational variation and stabilization in resynthesized allotetraploid Brassica juncea derived from diploid progenitors B. rapa and B. nigra.
BACKGROUND: Polyploidy is a major driver of plant evolution and crop improvement, generating novel variation in morphology, physiology, and agronomic traits. Brassica juncea (AABB, 2n = 36), a natural allotetraploid derived from B. rapa (AA) and B. nigra (BB), is an important oilseed and vegetable crop; however, its narrow genetic base limits further breeding gains. Resynthesized B. juncea (RBJ), developed from known progenitors, provides a tractable system to investigate polyploid stabilization, trait diversification, and generational variation. This study evaluated RBJ across nine generations (F1-S8) to elucidate generational variation in morphological, molecular, cytological, and oil content traits during progressive stabilization. RESULTS: Substantial variation was observed for key yield-related traits, including siliqua length, seeds per siliqua, and thousand-seed weight. High estimates of heritability, genotypic variance, and genetic advance indicated their potential utility in selection based improvement. Comparative analyses revealed a clear generational progression, characterized by relatively enhanced performance in early generations, increased recombination-driven variability in intermediate generations, and the partial stabilization of several traits in later generations. Generation mean analysis suggested the involvement of additive, dominance, and epistatic gene effects in trait inheritance. Molecular analysis using SSR markers confirmed the amphidiploid origin and genomic integrity of RBJ generations. Cytological assessments, pollen viability assays, and flow cytometric analysis collectively demonstrated stable chromosome numbers, improved fertility, and maintenance of ploidy stability across successive generations. CONCLUSIONS: The study provides valuable insights into the generational variation and stabilization of morphological, molecular, and oil content traits in resynthesized B. juncea. The findings suggest that variability arising from polyploidization and interspecific hybridization undergoes gradual reorganization across successive generations, leading to increased trait stabilization and more consistent expression of selected agronomic characteristics. Collectively, these results contribute to the understanding of early stabilization processes in RBJ, highlighting resynthesized polyploids as useful systems for studying variation and stabilization in allopolyploid crops.
Mustard Plant↗
[Proximate determinants of fertility in Cuba. The Bongaarts model].
"The results of the implementation of the Bongaarts method for quantitating the effects of [proximate] determinants on fertility are presented. The model used is of the multiplicative kind and relates the global fertility rate to the so called natural fertility rate. Thus, it is possible to quantitate and separate the effect of each determinant and thus find out what factors have been responsible for the rapid change in fertility [in Cuba] from 1972 on. The determinant of highest impact on the fertility level attained in each province was assessed. The most important results point [to] the use of contraceptives as the cause for the rapid decline in the fertility level and the married state as the variable conditioning provincial differences." (SUMMARY IN ENG AND FRE)
Americas↗
Risk factors for high-grade cervical intraepithelial neoplasia in patients with mild cytological dyskaryosis: human papillomavirus testing versus multivariate tree analysis of demographic data.
The objective of this study was to compare the use of molecular hybridization by hybrid capture methodology for human papillomavirus (HPV) with the use of demographic and lifestyle variables as intermediate triage in patients with cytological mild dyskaryosis. The study was designed as a prospective study using regression tree analysis of demographic data in consecutive patients who were subjected to colposcopic evaluation at the colposcopy clinic at the First Department of Obstetrics and Gynaecology, University of Milan (Milan, Italy). A total of 177 women were subjected to colposcopy because of a single routine Pap smear showing mild dyskaryosis. A structured interview, sampling for HPV testing for the detection of viral DNA by hybrid capture methodology, and colposcopic evaluation with cervical biopsies were performed for each subject. The accuracies of molecular hybridization for HPV and of the classification model based on the demographic and lifestyle variables in predicting patients with histologically high-grade cervical intraepithelial lesions were measured. The classification model based on the demographic and lifestyle variables showed comparable results with molecular hybridization for HPV (specificity, 0.75 versus 0.73; sensitivity, 0.61 versus 0.67, respectively). The use of demographic and lifestyle variables appears to be a simple and economic possibility for triaging patients with mild dyskaryotic smears in a screening program.
Adult↗
[Repercussion of postoperative pain, benefits attending to treatment].
Physiological responses to postoperative acute pain may impede organ functions (cardiovascular, pulmonary, coagulation, endocrine, gastrointestinal, central nervous system, etc). Pain alleviation improves patient's comfort, but also may minimise perioperative stress response, physiological responses and postoperative organ dysfunction, assist postoperative nursing and physiotherapy, enhance clinical outcome, and potentially shorten the hospital stay. Potent postoperative analgesia, especially by epidural route, may be associated with reduction in incidence and severity of many perioperative dysfunctions. Peridural analgesia using local anaesthetics is the best technique for decreasing postoperative stress after lower abdominal or lower limb surgery. Analgesia using either epidural or high doses of morphine may improve some cardiac variables such as tachycardia and ischaemia, but does not change the incidence of severe cardiac complications. For patients undergoing vascular or orthopaedic surgery, epidural analgesia can improve clinical outcome by preventing the development of arterial or venous thromboembolic complications. However, in comparative studies, the control groups did not receive adequate prophylactic treatment for thromboembolic complications. Epidural analgesia can hasten the return of gastrointestinal motility and shorten the hospital stay. Postoperative mental dysfunction is decreased using intravenous PCA morphine in the elderly. Epidural analgesia with local anaesthetics improves postoperative respiratory function but, for unknown reasons, these benefits are not associated with a decrease in respiratory complications. On balance, the mode of acute pain relief decreases adverse physiological responses and many intermediate outcome variables; however, there is inconclusive evidence that it affects clinical outcome. Major advances in postoperative recovery can be achieved by early aggressive perioperative care, including potent analgesia, early mobilisation and oral nutrition. As a result, the hospital stay may be shortened.
Analgesics↗
Birth weight distribution as an indicator of environmental effects on fetal development.
A medical birth registry was used for a geographical analysis of birth weight distribution. Nearly 900,000 Swedish singleton births, 1973-1981, were used for an analysis of the effect of some variables and for standardization for these variables. A marked change in the rate of low birth weight infants (LBW, less than 2,500 g) was seen in the country between 1976 and 1977. A U-formed effect of maternal age and of parity was demonstrated. A marked interaction between the effects of these two variables existed. Two social groups were compared and the well-known high rate of LBW infants associated with low socioeconomic conditions was demonstrated. Standardization for the variables mentioned influenced this effect only little but reduced the difference between the social groups concerning infants above 3.5 kg weight. The background data were used for analysis of restricted geographical areas.
Adult↗
Expression and localization of cyclo-oxygenase isoforms in non-small cell lung cancer.
The beneficial effects of cyclo-oxygenase (COX) inhibitors in both colon cancer and adenomatous polyps suggest a role for the prostanoid pathway in epithelial malignancy. Although variable prostanoid synthesis in non-small cell lung cancer (NSCLC) has been demonstrated in freshly obtained tissue, COX messenger ribonucleic acid (mRNA) and protein localization in such tumours had not been investigated ex vivo. Thirty-four cases of primary NSCLC were examined for both constitutive (COX-1) and inducible COX (COX-2) by means of in situ hybridization and immunohistochemistry. COX-1 mRNA expression was absent or below the level of detection via in situ hybridization. COX-1 immunohistochemistry demonstrated uniform faint cytoplasmic staining in tumour cells and stromal inflammatory cells. Semiquantitative analysis of COX-2 expression in NSCLC demonstrated the highest levels of both mRNA and protein in adenocarcinoma cells (n=10, p<0.005 compared with large cell and squamous cell carcinoma), intermediate and variable expression in large cell carcinoma (n=11) and low or absent expression in squamous cell tumours (n=13). Levels of COX-2 expression in infiltrating inflammatory cells was the same in all tumour types. In conclusion, tumour cell cyclo-oxygenase-2 rather than cyclo-oxygenase-1 expression may account for the variable prostanoid production seen in non-small cell lung cancer, and primary lung adenocarcinoma expresses the highest levels of cyclooxygenase-2. Assessment of cyclo-oxygenase-2 expression ex vivo should be performed in studies examining the potential therapeutic effects of cyclo-oxygenase inhibitors in non-small cell lung cancer.
Carcinoma, Non-Small-Cell Lung↗
Migration and marriage in the life course: a method for studying synchronized events.
"On the basis of a West German sample of residence histories that is representative of three birth cohorts, of which the one born in 1939-41 is analysed, log-linear techniques were applied to separate the effects of being married, and of getting married, on migration rates. Results show that the dependence of short and long distance moves on age substantially [diminishes] if marriage is considered as a synchronization variable. Moreover, the common finding that married persons move less than the unmarried is reversed at short distances if marriage is taken into account as an event which influences the probability of another (event dependence)." (SUMMARY IN FRE)
Age Factors↗
Fracture faces of zonulae occludentes from "tight" and "leaky" epithelia.
Epithelia vary with respect to transepithelial permeability. In those that are considered "leaky", a large fraction of the passive transepithelial flux appears to follow the paracellular route, passing across the zonulae occludentes and moving down the intercellular clefts. In "tight" epithelia, the resistance of the paracellular pathway to passive flux is greatly increased. To see whether differences in the morphology of the zonula occludens could contribute to this variability in leakiness among epithelia, replicas of zonulae occludentes in freeze-fractured material from a variety of tight and leaky epithelia were examined. The junctions appear as a branching and anastomosing network of strands or grooves on the A and B membrane fracture faces, respectively. It was found that the zonula occludens from a "very leaky" epithelium, the proximal convoluted tubule of the mouse kidney, is extremely shallow in the apical-basal direction, consisting in most places of only one junctional strand. In contrast, the "very tight" frog urinary bladder exhibits a zonula occludens that is relatively deep (>0.5 microm) in the apical-basal direction, and consists of five or more interconnected junctional strands interposed between luminal and lateral membrane surfaces. Epithelia of intermediate permeabilities exhibited junctions with intermediate or variable morphology. Toad urinary bladder, mouse stomach, jejunum, and distal tubule, rabbit gallbladder, and Necturus kidney and gallbladder were also examined, and the morphological data from these epithelia were compared to physiological data from the literature.
Animals↗