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PubMed1997

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↗

PubMed1992

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↗

PubMed1991

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↗

PubMed2026

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↗

PubMed1998

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↗

PubMed1998

[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↗

PubMed1987

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↗

PubMed1973

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↗

PubMed1988

A comprehensive analysis of myocardial infarction due to left circumflex artery occlusion: comparison with infarction due to right coronary artery and left anterior descending artery occlusion.

Forty consecutive patients with creatine kinase-MB confirmed myocardial infarction due to circumflex artery occlusion (Group 1) were prospectively evaluated and compared with 107 patients with infarction due to right coronary artery occlusion (Group 2) and 94 with left anterior descending artery occlusion (Group 3). All 241 patients underwent exercise thallium-201 scintigraphy, radionuclide ventriculography, 24 h Holter electrocardiographic (ECG) monitoring and coronary arteriography before hospital discharge and were followed up for 39 +/- 18 months. There were no significant differences among the three infarct groups in age, gender, number of risk factors, prevalence and type of prior infarction, Norris index, Killip class and frequency of in-hospital complications. Acute ST segment elevation was present in only 48% of patients in Group 1 versus 71 and 72% in Groups 2 and 3, respectively (p = 0.012), and 38% of patients with a circumflex artery-related infarct had no significant ST changes (that is, elevation or depression) on admission (versus 21 and 20% for patients in Groups 2 and 3, respectively) (p = 0.001). Abnormal R waves in lead V1 were more common in Group 1 than in Group 2 (p less than 0.003) as was ST elevation in leads I, aVL and V4 to V6 (p less than or equal to 0.048). These differences in ECG findings between Group 1 and 2 patients correlated with a significantly higher prevalence of posterior and lateral wall asynergy in the group with a circumflex artery-related infarct. Infarct size based on peak creatine kinase levels and multiple radionuclide variables was intermediate in Group 1 compared with that in Group 2 (smallest) and Group 3 (largest). During long-term follow-up, the probability of recurrent cardiac events was similar in the three infarct groups. When patients with a circumflex artery-related infarct were stratified according to the presence or absence of abnormal R waves in lead V1 or V2, the abnormal R wave group had more admission ST elevation (p = 0.025), a larger infarct (p less than 0.05) and more extensive coronary artery disease (p = 0.027). In fact, all patients with a circumflex artery-related infarct and an abnormal R wave in lead V1 had multivessel disease. An abnormal R wave in lead V1 had a 96% specificity for circumflex versus right coronary artery-related infarction but a sensitivity of only 21%. Discriminate function analysis of all admission historical and ECG variables identified inferior and lateral ST elevation as independent predictors of circumflex artery-related infarction...

Angiography↗

PubMed1994

Immunization coverage and infant mortality rate in developing countries.

We examined whether immunization coverage (IMC) is one of the predictors of infant mortality rate (IMR), as a single indicator representing the availability of primary health care (PHC) services in developing countries. Multiple regression analysis showed that partial correlation coefficients for IMR with immunization coverage (-0.224), logarithm of per capita GNP (-0.294), total fertility rate (0.269), and adult literacy rate (-0.325) were all statistically significant (p < 0.001) in 97 developing countries which make up more than 97% of the population in all the developing countries of the world. Multiple correlation coefficients of IMR with these four variables in 97 countries was 0.921. Thus, more than 80% of variation of IMR in developing countries were explained by the variation of the four variables. The study also showed that IMC was well correlated (simple correlation) with the four indicators of the availability of primary health care services; access to local care (0.730), care of pregnant women (0.603), delivery care (0.666), and infant care (0.553), all of which were statistically significant (p < 0.001) in the 48 developing countries which make up 42% of the population of all developing countries. Multiple correlation coefficients of these four variables was 0.787. About 60% of the variation of IMC will be explained by the variation of the four variables. Thus we conclude that immunization coverage is one of the main predictors of the infant mortality rate. It represents one of the health intervention components which can be used as a proxy indicator of the availability of PHC service in developing countries.

Adult↗

PubMed1984

Glial fibrillary acidic protein (GFAP) immunoreactivity in peripheral nerve sheath tumors.

A spectrum of 24 benign and malignant nerve sheath tumors and 10 non-neural spindle-cell tumors were studied by light microscopy for the presence of glial fibrillary acidic protein (GFAP) immunoreactivity by the peroxidase-antiperoxidase (PAP) technique. In 8 cases, these results were compared to their electron microscopic appearances. Seventy percent (7 of 10) of benign schwannomas and 50% (4 of 8) of benign neurofibromas demonstrated focal to diffuse GFAP immunoreactivity. None of the malignant nerve sheath tumors nor any of the non-neural spindle-cell neoplasms contained demonstrable GFAP immunoreactivity. Similarly, no GFAP immunoreactivity could be detected in Schwann cells in normal peripheral nerves. The solitary benign schwannoma available for electron microscopic study demonstrated diffuse and abundant cytoplasmic intermediate filaments, and this tumor displayed diffuse and intense GFAP immunoreactivity. Two benign neurofibromas showed a more variable content of intermediate filaments ultrastructurally, and their GFAP immunoreactivity was variable. All five malignant nerve sheath tumors studied by electron microscopy displayed a variable complement of intermediate filaments; however, none of these tumors possessed GFAP immunoreactivity, suggesting that these intermediate filaments are either members of a different class of intermediate filaments or may perhaps represent "altered" GFAP not recognized by these antisera.

Cytoskeleton↗

PubMed1995

Adolescent contraceptive use and its determinants in Bangladesh: evidence from Bangladesh Fertility Survey 1989.

This study is concerned with contraceptive use among the currently married adolescents in Bangladesh utilizing the 1989 Bangladesh Fertility Survey (BFS) data. The study analyzes the factors affecting the current use of contraception among the adolescents through bivariate and multivariate logistic regression analysis. The results indicate that although adolescents have almost universal knowledge about contraceptive methods, only 15 percent are currently using any method of contraception. The corresponding figures for the adults and for the nation as a whole are 34.4 percent and 31.4 percent, respectively. Among the individual methods currently used by the adolescents, the pill appears as the most popular method, followed by safe period. A substantial proportion of the adolescents were found to rely on the traditional methods of contraception. Among the socio-economic variables (as revealed by the logistic regression analysis), respondents' education, participation in the family planning decision, visit by family planning workers, region of residence, husband's occupation and possession of electricity in the household appear as the most significant factors determining the current use of contraception among the adolescents.

Adolescent↗

PubMed1990

Socio-demographic and gynaecological variables of maternal mortality in a Kenyan subdistrict: January 1981-September 1988.

A study on institutional maternal mortality in Thika subdistrict is presented for the period January 1981 through September 1988. There were 86,248 live births in the various government and private institutions in the sub-district and 164 maternal deaths, giving a maternal mortality rate of 190/100,000. The various associated socio-demographic factors are analysed.

Adolescent↗

PubMed1991

Proximate determinants of child mortality in Liberia.

The study looks at the effects of maternal sociodemographic characteristics and the quality of the environment on child survival through two intervening variables, breast-feeding and prenatal care. A linear structural equation modelling approach was used to examine infant and child survival based on a weighted sample of 5180 Liberian children aged 0-5 years. The findings confirm previous studies, but also reveal complex relationships of the role of education, maternal age and breast-feeding in enhancing child survival.

Breast Feeding↗

PubMed1990

Contraceptive behavior among sexually active Hispanic adolescents.

The purpose of this study was to examine those factors associated with the contraceptive behavior of a national representative sample of Hispanic female adolescents. The subjects included all (n = 85) unmarried, sexually active Hispanic women, aged 15 to 19, from the 1982 National Survey of Family Growth. Contraceptive behavior was measured on a normalized scale, ranging from oral contraceptives to no contraception. Mexican/American and Central/South American background females were more likely (p less than 0.031) to use effective birth control than Puerto Rican, Cuban, and other Hispanic background subjects. Twenty additional social, behavioral, and demographic variables were found to be significantly associated (p less than 0.05) with contraceptive behavior. Based on multiple regression analysis, seven of these variables were found to explain 62% (p less than 0.0001) of the variation in the contraceptive behavior of this sample. Poorer contraceptive behavior was associated with noncompliance with the initial birth control method used (33.8%), lower coital frequency (8.3%), older postmenarchial age (5.7%), failure to use birth control at first coitus (4.6%), fewer years dating (4.0%), lower frequency of church attendance (3.3%), and never having experienced a pregnancy scare (2.0%). These findings suggest that the contraceptive behavior of Hispanic female adolescents is a dynamic process that can be understood in the context of previous sexual and contraceptive behavior.

Adolescent↗

PubMed1979

Application of discriminant analysis to level of performance of alcoholics and nonalcoholics on Wechsler-Bellevue and Halstead-Reitan subtests.

Investigated the utility of subtests from the Wechsler-Bellevue Intelligence Scale and the Halstead-Reitan Neuropsychological Test Battery to differentiate between alcoholics and nonalcoholics (N = 76). Analyses of variance indicated that the alcoholics were more impaired than nonalcoholics. It was found that the Wechsler-Bellevue Performance subtests were more discriminative than were Verbal subtests, with performance on the Halstead-Reitan variables being intermediate. The nine measures that differentiated most significantly between groups were subjected to a stepwise multivariate discriminant analysis. The resulting function correctly classified Ss with an overall accuracy of 74.7%. It was found that the Block Design subtest was the best single discriminator. The findings were discussed in relationship to previous findings and with respect to general issues of clinical neuropsychological assessment.

Alcoholism↗

PubMed1995

Specific compositional patterns of synonymous positions in homologous mammalian genes.

All 69 homologous coding sequences that are currently available in four mammalian orders were aligned and the synonymous (ie., third) positions of quartet (fourfold degenerate) codons were divided into three classes (that will be called conserved, intermediate, and variable), according to whether they show no change, one change, and more than one change, respectively. The three classes were analyzed in their compositional patterns. In the majority of GC-rich genes, the three classes of positions (but especially conserved positions) exhibited significantly different base compositions compared to expectations based on a "random" substitution process from the "ancestral" (consensus) sequence to the present-day (actual) sequences. Significant differences were rare in GC-poor genes. An analysis of the present results indicates that natural selection plays a role in the synonymous nucleotide substitution process, especially in GC-rich genes which represent the vast majority of mammalian genes.

Animals↗

PubMed1977

Polymorphism of red cell glyoxalase 1. With special reference to South and Southeast Asia and Oceania.

Glyoxalase polymorphism has been studied in 7296 persons from populations in South Asia, Southeast Asia, Oceania, Iran and Colombia. The GLO frequencies are very low in most of Oceania, including Australia, somewhat higher in Southeast Asia, and intermediate though variable in India. In Iran the GLO frequency is similar to that in Europe. The value for the single amerindian group in Colombia is nearly 30%.

Asia, Southeastern↗