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PubMed1999

Prediction of community integration and vocational outcome 2-5 years after traumatic brain injury rehabilitation in Australia.

OBJECTIVES: To predict community integration and vocational outcomes 2-5 years after traumatic brain injury (TBI). DESIGN: Multivariate correlational design incorporating retrospective data collection and questionnaire follow-up. METHODS: Four hundred and forty six patients admitted to a Head Injury Unit between 1991 and 1995 were contacted. Data on predictor variables (demographic, injury severity and functional) were retrieved from hospital records. Community integration and vocational outcome was assessed by self-administered questionnaire. Two hundred and nine patients/carers completed and returned the questionnaires. Mean follow-up was 3.5 years. Data were analysed by descriptive statistics, multiple regression and discriminant analysis using SPSS. RESULTS: Community integration was predicted by age, disability level and cognition. Length of PTA, cognition, disability levels, GCS, functional status, length of acute stay and prior occupation discriminated those who returned to work. A total of 46.5% returned to work with 74.5% in the same or similar jobs. CONCLUSION: Long term outcomes post-TBI can be predicted by demographic, injury severity and functional status variables.

Activities of Daily Living↗
PubMed2004

Risk factors associated with colibacillosis outbreaks in caged layer flocks.

Colibacillosis appears to be of increasing significance in layer flocks, but there have been no studies of the risk factors associated with outbreaks. This study aimed to investigate the possible associations between risk factors of non-infectious nature and outbreaks of mortality due to colibacillosis in flocks of caged layer hens. Information on management, biosecurity measures and housing conditions was collected in 20 flocks suffering from the disease and in 20 clinically healthy control flocks. The data were processed using multiple logistic regression. The statistical analysis demonstrated that an increase in the distance to the nearest poultry farm by 1 km was associated with a six-fold decreased risk of an outbreak of colibacillosis (odds ratio=0.16). Furthermore, a 1 l increase in cage volume per hen was associated with a 33% decrease in the risk of an outbreak (odds ratio=0.75). It was concluded that the distance between poultry farms and the hen density in the cages are important risk factors for outbreaks of colibacillosis in flocks of layer hens.

Animal Husbandry↗
PubMed2006

Growth from birth to age 19 for children in Sweden born in 1981: descriptive values.

AIM: To describe Swedish children's growth (i.e. height, weight and body mass index) from birth to age 19 y. METHODS: Every infant born on the 15th of any month in 1981 and living in Sweden as of 31 December 1989 was sampled. Longitudinal data were collected from childhood and school health records, and analysis by piecewise linear regression gave statistical descriptions of height, weight and body mass index for every age group. RESULTS: The data include measurements of 3107 of 3158 sampled children; 1.6% of individuals are missing, so non-response bias is minimal. Thus, statistical descriptions and comparisons with similar data sets can be based on data with unusually high national representativeness. Selected subgroups (i.e. individuals born outside Sweden, suffering from chronic disease causing major growth impairment, or with birthweight <2500 g) deviate in growth pattern, and exclusion of these subgroups increases means and decreases SD for height but only slightly influences summary statistics for weight and body mass index. CONCLUSION: This study represents, without selection bias, the current growth situation among children and adolescents in Sweden, enabling both epidemiological comparisons over time and comparisons with other national surveys.

Adolescent↗
PubMed2004

Antifouling potential of lubricious, micro-engineered, PDMS elastomers against zoospores of the green fouling alga Ulva (Enteromorpha).

The settlement and release of Ulva spores from chemically modified, micro-engineered surface topographies have been investigated using poly(dimethyl siloxane) elastomers (PDMSe) with varying additions of non-network forming poly(dimethyl siloxane) based oils. The topographic features were based on 5 microns wide pillars or ridges separated by 5, 10, or 20 microns wide channels. Pattern depths were 5 or 1.5 microns. Swimming spores showed no marked difference in settlement on smooth surfaces covered with excess PDMS oils. However, incorporation of oils significantly reduced settlement density on many of the surfaces with topographic features, in particular, the 5 microns wide and deep channels. Previous results, confirmed here, demonstrate preferences by the spores to settle in channels and against pillars with spatial dimensions of 5 microns, 10 microns and 20 microns. The combination of lubricity and pillars significantly reduced the number of attached spores compared to the control, smooth, unmodified PDMSe surfaces when exposed to turbulent flow in a flow channel. The results are discussed in relation to the energy needs for spores to adhere to various surface features and the concepts of ultrahydrophobic surfaces. A factorial, multi-level experimental design was analyzed and a 2nd order polynomial model was regressed for statistically significant effects and interactions to determine the magnitude and direction of influence on the spore density measurements between factor levels.

Analysis of Variance↗
PubMed2003

Daily surface UV exposure and its relationship to surface pollutant measurements.

For the past 30 years, the stratospheric ozone layer has decreased in the Northern Hemisphere. The main effect of this ozone decrease was an expected increase in the UV radiation at the Earth's surface, but there has been no clear evidence of an increasing urban trend in surface UV. This study shows that specific air pollutants can reduce the increased surface levels of UV radiation and offers an explanation for why the expected surface UV increases have not been observed, especially in urban regions. A U.S. Environmental Protection Agency (EPA) UV monitoring site at the University of California at Riverside combined with air pollution data from a site operated by the California Air Resources Board in Rubidoux, CA, provided the basis of this study. The 1997 South Coast Ozone Study (SCOS-97) provided three key ingredients: black carbon, PM10 concentrations, and collocated radiometric measurements. The Total Ozone Mapping Spectrometer (TOMS) satellite data were used to provide the stratospheric ozone levels that were included in the statistical model. All of these input parameters would be used to test this study's hypothesis: the expected increase of surface UV radiation, caused by decreases in stratospheric ozone, can be masked by increases in anthropogenic emissions. The values for the pollutants were 7:00 a.m.-5:00 p.m. averages of the instrument's values taken during summer 1997. A statistical linear regression model was employed using the stratospheric ozone, black carbon, PM10, and surface ozone concentrations, and the sin (theta) and cos (theta). The angle theta is defined by theta = 2pi (Julian date/365). This model obtained a coefficient of determination of 0.94 with an uncertainty level (p value) of less than 0.3% for all of the variables in the model except ground-level ozone. The final model, regressed against a data set from a remote, western North Carolina site, resulted in a coefficient of determination of 0.92. The model shows that black carbon can reduce the Diffey-weighted UV levels that reach the surface by as much as 35%, depending on the season.

Air Pollutants↗
PubMed2005

Using human microarrays to identify differentially expressed genes associated with increased steroidogenesis in boars.

Human microarrays are readily available, and it would be advantageous if they could be used to study gene expression in other species, such as pigs. The objectives of this research were to validate the use of human microarrays in the analysis of porcine gene expression, to assess the variability of the data generated, and to compare gene expression in boars with different levels of steroidogenesis. Cytochrome b5 (CYB5) expression was used to assess array detection sensitivity. Samples having high or low CYB5 RNA levels were hybridized to microarrays to determine if the known expression difference could be detected. Six hybridizations were conducted using human microarrays containing 3840 total spots representing 1718 characterized human ESTs. To analyze gene expression in boars with different levels of steroidogenesis, testis RNA from four boars with high levels of plasma estrone sulphate was hybridized to testis RNA from four boars with lower levels. Eight microarray hybridizations were conducted including fluor-flips. Self-self hybridizations were also conducted to assess the variability of array experiments. The Cy5 and Cy3 intensity values for each array were normalized using a locally weighted linear regression (LOESS). Statistical significance was assessed using a Student's t-test followed by the Benjamini and Hochberg multiple testing correction procedure. Quantitative real-time PCR (Q-RT-PCR) was used to verify select gene expression differences. The results show that CYB5 was significantly overexpressed in the high CYB5 sample by 1.8 fold (P < 0.05), verifying the known expression difference. The average log2 ratio of the majority of genes (1643) falls within one standard deviation of the mean, indicating the data were reproducible. In the high versus low steroidogenesis experiment, seven genes were significantly overexpressed in the high group (P < 0.05). Quantitative real-time PCR was used to validate five genes with the highest fold change, and the results corroborated those found by the microarray experiments. The results of the self-self hybridizations showed that no genes were significantly differentially expressed following the application of the Benjamini and Hochberg multiple testing correction procedure. The results presented in this report show that human arrays can be used for gene expression analysis in pigs.

Animals↗
PubMed2006

Normal standards of fetal behavior assessed by four-dimensional sonography.

OBJECTIVE: In this prospective randomized study, fetal behavior was investigated in order to determine the standard parameters of fetal movements and facial expressions in all three trimesters of normal pregnancy. METHODS: Sixty-three pregnant women with singleton pregnancies in all trimesters were included in the investigation. Four-dimensional (4D) ultrasound was performed for each patient over a 30-minute period. Variables of maternal and fetal characteristics including gestational age, eight fetal movement patterns in the first trimester, and sixteen parameters of fetal movement and fetal facial expression patterns in the second and third trimesters were recorded for the construction of fetal neurological charts. RESULTS: In the first trimester, a tendency towards an increased frequency of fetal movement patterns with increasing gestational age was noticed. Only the startle movement pattern seemed to occur stagnantly during the first trimester (p > 0.05). At the beginning of the second trimester, the frequency of fetal movement patterns tended to increase. During the second and third trimester, multiple regression and polynomial regression revealed statistically significant changes in tongue expulsion (p < 0.05), smiling (p < 0.05), grimacing (p < 0.05), swallowing (p < 0.05), eye blinking (p < 0.01), head movements, and all hand to body contact movements (p < 0.01), except for head anteflexion (p > 0.05). There were no statistically significant changes during the second and third trimesters in mouthing, yawning, and sucking (p > 0.05). At the middle of the third trimester, the fetuses displayed decreasing or stagnant incidence of fetal facial expressions except for eye blinking, which showed increased frequency with increasing gestational age. A statistically significant correlation was found between all head movements and hand to body contact patterns during the second and third trimesters except for head anteflexion (r = -0.231; p > 0.05). CONCLUSIONS: The full range of quantitative fetal facial expressions and fetal movement patterns can be assessed successfully by 4D sonography. It is important to be able to assess normal fetal behavior throughout gestation to identify abnormal behavior before birth.

Female↗
PubMedDate not supplied

The span of reproduction in Egypt.

This study shows long reproductive spans to be associated with low levels of women's education, rural residence, remarriage, early marriage age, and high parity. Effects are statistically significant.

Adolescent↗
PubMedDate not supplied

Postpartum sexual abstinence, breastfeeding, and childspacing, among Yoruba women in urban Nigeria.

This paper examines the extent to which the traditional practice of sexual abstinence during lactation has broken down among Yoruba women residents in urban areas. The first major finding is that there is a gradual erosion of the tradition, and the dominant factors of modernization are education of the woman and the use of contraception. The second major finding is that the breakdown of postpartum sexual taboos has statistically significant negative consequences on duration of lactation, although the negative impact of woman's education is greater. The third major finding is that duration of breastfeeding reduces birth interval significantly only when it is less than 15 months, and that both durations of breastfeeding and birth intervals have declined over time. The first two findings suggest further reductions in the proportion of women who abstain from sexual relations during lactation and in durations of breastfeeding as more women become more educated. Significant declines in birth intervals may follow soon after.

Adult↗
PubMedDate not supplied

Female education, age, parity, and reproduction cessation in Ghana.

Data from the 1988 Ghana Demographic and Health Survey is employed to determine the existence of a relationship between the amount of education a woman has and her intent to cease childbearing. The findings are that with increasing levels of education, a female's desire to cease reproduction also increases. However, this relationship is obscured if parity is not controlled.

Adult↗
PubMedDate not supplied

Achievement of reproductive intentions in Sri Lanka, 1982-1985: a longitudinal study.

The achievement or reproductive intentions of Sri Lankan women was examined by using longitudinal data for the period 1982-85. Aggregate consistency between reproductive intentions and behavior was almost perfect, but at the individual level there were inconsistencies. Among those who wanted to have no more children, 23 per cent reported a birth in the intersurvey period of 3 years and 2 months, while failures to have a wanted birth stood at 36 per cent. There was a clear declining trend in the former type of inconsistencies in Sri Lanka, but the latter type has increased, possibly due to a continuing decline in family size ideals or due to deferred childbearing. Even though inconsistencies existed, expressed fertility intentions in 1982 significantly influenced the fertility outcome. The study also has a methodological focus on whether to include sterilized women when fertility intentions and behavior are examined longitudinally, but no specific problems were found with their inclusion. Results indicate that, apart from the intention variable, age, marital duration, family size, and education of husband and wife variables all influenced fertility in the follow-up period.

Adolescent↗
PubMedDate not supplied

Smoothed breastfeeding durations and waiting time to conception.

Breastfeeding beyond the resumption of mother's menstruation plays a significant role in the proximate determinants of fertility. Breastfeeding and postpartum amenorrhoea data collected from retrospective surveys usually exhibit digit preferences. Here, these heaping errors were smoothed by B-spline and used in multivariate models of risk of conception to investigate the contraceptive effect of breastfeeding. The data used come from a 1987 Indian survey. Results show that lactation, after mother's menses resume, reduces the risk of conception. Heaping in breastfeeding data attenuates this relationship. When adjustment is made, breastfeeding reduced the rate of conception by 47 per cent; the reduction, with adjusted data, was 63 per cent.

Adult↗
PubMed1982

Quantitative studies on T cell diversity. III. Limiting dilution analysis of precursor cells for T helper cells reactive to xenogeneic erythrocytes.

Splenic T cells exposed to concanavalin A (Con A), and subsequently to factors produced by rat spleen cells in response to Con A (Con A sup), acquire the ability to function as helper T (TH) cells in response to xenogeneic erythrocytes (RBC). Help is measured as the reconstitution of the plaque-forming cell response of a spleen cell population depleted of T cells by treatment with anti-Thy-1 serum and complement. We propose that precursor TH cells differentiate during the in vitro treatment into mature TH cells. As differentiation occurs under limiting dilution conditions, an estimation of the precursor frequency should in principle be possible. However, a single-hit Poisson distribution does not fit our data. Instead, we observe, dependent on the T cell concentration, three separate "peaks" of response. In many experiments, using sheep, horse, and chicken RBC as antigens, we reproducibly find these "peaks" at 40-190, 600-3,000, and 20,000-100,000 T cells, placed into limiting dilution cultures, respectively. By various experiments we can show that the helper activity is not due to passively transferred rat factors, but to the titrated cells themselves. The active cell is a T cell that appears to function in an antigen-specific way and to require direct cell contact to do so. It thus resembles the classical helper T cell. As we find precursor TH cells already at very low concentrations of T cells, we titrated the range between 0 and 100 T cells/well carefully. The bent shape of the titration curves does not always allow a statistically satisfying regression analysis, and we therefore cannot estimate precise precursor frequencies from every experiment. However, a common sense argument can be made that these frequencies must be on the order of 1/10-1/100 T cells. We propose that the limiting dilution curves obtained in this system most likely reflect fundamentally important cellular interactions that regulate immunological effector functions. We favor a concept of independently interacting sets of helper and suppressor T cells of various frequencies, but other models are possible.

Animals↗
PubMed2004

Modification of the incidence of drug-associated symmetrical peripheral neuropathy by host and disease factors in the HIV outpatient study cohort.

BACKGROUND: We sought to identify factors associated with the clinical diagnosis of symmetrical peripheral neuropathy (SPN) during the era of highly active antiretroviral therapy (HAART) in a retrospective, longitudinal cohort analysis. METHODS: Patients infected with human immunodeficiency virus type 1 were evaluated for clinical signs of SPN and its association with immunologic, virologic, clinical, and drug treatment factors by means of univariate and multivariate logistic regression analyses. RESULTS: Of 2515 patients, 329 (13.1%) received a diagnosis of SPN. In the logistic regression analysis, statistically significant non-drug-based risk factors for SPN were age >40 years (adjusted odds ratio [aOR], 1.17), diabetes mellitus (aOR, 1.79), white race (aOR, 1.33), nadir CD4(+) T lymphocyte count <50 cells/mm(3) (aOR, 1.64), CD4(+) T lymphocyte count 50-199 cells/mm(3) (aOR, 1.40), and viral load >10,000 copies/mL at first measurement (aOR, 1.44). Although initial use of didanosine, stavudine (40 mg b.i.d.), nevirapine, or 4 protease inhibitors was associated with SPN (ORs for all 4 treatments, >1.41), the strength of association decreased with continued use of all medications studied. CONCLUSION: Since HAART was introduced, the incidence of SPN has decreased. Host factors and signs of increased disease severity were associated with an increased risk of developing SPN during the initial period of exposure to drug therapy. Immunity improved and the risk of SPN decreased with continued use of HAART. Delaying the initiation of therapy may select those individuals who will be more likely to develop SPN, and earlier initiation of HAART may decrease the risk of developing this common problem, as well as increase the therapeutic effects and decrease the toxic effects of the drugs.

Anti-HIV Agents↗
PubMed2000

Hematological complications and quality of life in hospitalized AIDS patients.

The relationships among the biological and physiological indicators of cytopenias in AIDS and measures of quality of life are not well characterized. The purpose of this secondary analysis was to determine the relationships among anemia, neutropenia and thrombocytopenia and characteristics of the individual, physiological markers, symptoms, functional status, general health perceptions, and well-being in people with AIDS. The five dimensions of the Wilson and Cleary model of health-related quality of life provided the conceptual model for this study. In addition to descriptive statistics, logistic regression was used to analyze clusters of variables. The sample of 146 hospitalized patients with AIDS had an 85% prevalence of anemia, a 53% prevalence neutropenia and a 33% prevalence of thrombocytopenia. The mean age was 38 years old, 19% were female, 35% were white, 27% had a history of injection drug use and the mean T-helper cell count was 74 mm3. The five dimensions of the Wilson and Cleary model offered significant predictability for anemia only. Patients with higher symptom scores were more likely to have treatable anemia, defined as a hematocrit of < 30%. Treatable anemia was also associated with lower self-care scores and lower T-helper cells. Fifty-four percent of the cohort were candidates for colony stimulating factors, while only 17% of those eligible received them. These data suggest suboptimal treatment of anemia and neutropenia in this cohort of AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Clinical and field studies of human lactation: methodological considerations.

A variety of studies has been completed to assess selected methods that are presently being used or might potentially be used to evaluate lactation performance. During 64 test-weighings of infants before and after the consumption of a known amount of milk, the mean +/- SD "recovery" of milk ingestion was 94.9 +/- 13.2%. The weight of milk extracted by a mechanical pump was approximately 7% greater than the amount measured during test-weighings of infant of the same women within periods of 1 wk. To evaluate the possibility of performing abbreviated studies in field settings, the proportion of 24-h milk consumption received during 12 daytime hours was measured by test-weighings. Daytime consumption ranged from 46 to 58% of 24-h consumption (mean +/- SD = 52 +/- 3%). Attempts to predict the amount of milk consumption during 341 daytime studies from the age of infants and their frequency and duration of feedings met with limited success. Although each independent variable was significantly correlated with the amount consumed (multiple r = 0.69, p less than 0.001), the SE of the estimate (Sy.x) was relatively large. The effects of time of day and side of extraction on the volume and composition of extracted milk were determined during 24-h studies of seven women. There were significant changes in the concentration of fat (p less than 0.001) and nitrogen (p = 0.003) during the day and significant differences in the concentrations of fat (p = 0.04) and lactose (p = 0.04) and in the volume (p less than 0.001) of milk produced by each breast. The importance of these findings for the planning and interpretation of studies of human lactation is discussed.

Adolescent↗
PubMed1990

Maternal and fetal responses to the stresses of lactation concurrent with pregnancy and of short recuperative intervals.

In many regions of the world, women breastfeed one child while pregnant with the next. Among rural Guatemalan women participating in a nutrition-supplementation trial, lactation overlapped with pregnancy in 253 of 504 (50.2%) of the pregnancies. For cases where overlap occurred, 41.4% continued to breast-feed into the second trimester and 3.2%, in the third trimester. The maternal and fetal responses to the energetic stresses of overlap and of the duration of the recuperative (nonpregnant, nonlactating) interval were assessed. Overlap resulted in increased supplement intake. Short recuperative periods (less than 6 mo) resulted in increased supplement intake and reduced maternal fat stores. The energetic stresses of overlap and short recuperative periods did not significantly affect fetal growth. The mother appears to buffer the energetic stress, protecting fetal growth. This research demonstrates that evidence of depletion of maternal nutrient stores caused by a demanding reproductive history is found when reproductive stress is characterized adequately.

Anthropometry↗