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991.
To determine if persons with the Prader-Willi syndrome (PWS) have increased psychopathology when compared with matched controls, and whether there is a specific behavior phenotype in PWS, the behavior of 46 persons with PWS was compared with that of control individuals derived from a community sample (N = 454) of persons with mental retardation (MR). Behaviors were studied using the Developmental Behaviour Checklist, an instrument of established validity in the evaluation of behavioral disturbance in individuals with MR. PWS subjects were found to be more behaviorally disturbed than controls overall, and especially in antisocial behavior. In addition, some individual behaviors were more common in PWS subjects than controls. When these behaviors are considered together with findings from other studies using acceptably rigorous methods, a consensus behavior phenotype for PWS can be formulated. This will provide a valid foundation for studies of the mechanism of genetic pathogenesis of behavior in PWS. 相似文献
992.
CF Poets 《Canadian Metallurgical Quarterly》1998,26(6):424-428
A previously healthy 8-month-old infant experienced a dramatic change in affect, motor patterns, and appetite after a brief (4-day) separation from her parents. She went from being a happy, interactive, and engaging child to being withdrawn, with limited vocalization, spontaneous motor activity, or interest in her environment. For the first 3 days after her parents returned home, she refused solid food and most of the formula or water she was offered. Over the following week, her appetite increased minimally. Her parents were concerned about her apathy, excessive quietness, and lack of interest in food, toys, or their own attempts to engage her in play. At the pediatrician's office, she was significantly less interactive and playful compared with previous visits. Her temperature, heart rate, and respiratory rate were normal. Although there were no objective signs of dehydration, her weight was 8 ounces less than the previous recorded weight 1 month ago. Results of the physical examination were normal, with the exception of neurological and behavioral findings. She had mild, generalized decreased tone and strength, with normal deep tendon reflexes, a sad facial appearance with sustained furrowing of the lines in her forehead, difficulty in eliciting a social smile, and limited spontaneous sounds. There was an absence of focal neurological findings, a flat open anterior fontanel, and a head circumference measurement consistent with previous recorded results. There were no cutaneous bruises, and findings of her funduscopic examination did not reveal retinal hemorrhage. Before the 4-day holiday, child care was provided almost exclusively by her mother at home. On only two previous occasions, at 4 and 6 months of age, this first child of 20-year-old high school graduate parents was cared for by a neighbor when the parents went out to a movie theater. She cried for about 10 minutes when the parents left on these occasions. Her mother stated that she felt anxious about leaving the child for several days, but she and her husband decided that they needed a break and planned the 4-day vacation. Child care was provided by the neighbor, who did not notice any unusual behavior or refusal to feed while in her care during the parents' absence. 相似文献
993.
MC Poirier A Weston B Schoket H Shamkhani CF Pan MA McDiarmid BG Scott DP Deeter JM Heller D Jacobson-Kram N Rothman 《Canadian Metallurgical Quarterly》1998,7(6):545-551
Biomarkers of polycyclic aromatic hydrocarbon (PAH) exposure and genetic biomarkers of potential cancer susceptibility were determined in a group of United States Army soldiers who were deployed to Kuwait and Saudi Arabia in 1991 in the aftermath of the Persian Gulf War. Because hundreds of oil well fires were still burning, there was concern that ground troops stationed in Kuwait might be exposed to high levels of PAHs and other toxicants. The United States Army Environmental Hygiene Agency monitored air and soil for ambient PAHs. In addition, a group of 61 soldiers was involved in the biomonitoring study reported here. These soldiers kept diaries of daily activities and provided blood and urine samples in Germany (June) before deployment to Kuwait, after 8 weeks in Kuwait (August), and 1 month after the return to Germany (October). Here we present data for PAH-DNA adducts measured by immunoassay in blood cell DNA samples obtained at all three sampling times from 22 soldiers and bulky aromatic adducts measured by 32P-postlabeling in blood cell DNA samples from 20 of the same soldiers. Urinary 1-hydroxypyrene-glucuronide levels were determined by synchronous fluorescence spectrometry in a matched set of samples from 33 soldiers. Contrary to expectations, environmental monitoring showed low ambient PAH levels in the areas where these soldiers were working in Kuwait. For both DNA adduct assays, levels were the lowest in Kuwait in August and increased significantly after the soldiers returned to Germany (October). Urinary 1-hydroxypyrene-glucuronide levels were also lowest in Kuwait and highest in Germany, but the differences were not statistically significant. The PAH-exposure biomarker levels were not significantly influenced by polymorphic variations of CYP1A1 (MspI) and glutathione S-transferases M1 and T1. Overall, the data suggest that this group of soldiers was not exposed to elevated levels of PAHs while deployed in Kuwait. 相似文献
994.
J Arters CF Hohmann J Mills O Olaghere J Berger-Sweeney 《Canadian Metallurgical Quarterly》1998,37(4):582-594
The nucleus basalis magnocellularis (nBM) provides the primary source of cholinergic input to the cortex. Neonatal lesions of the nBM produce transient reductions in cholinergic markers, persistent abnormalities in cortical morphology, and spatial navigation impairments in adult mice. The present study examined sex differences in the effects of an electrolytic nBM lesion on postnatal day 1 (PND 1) in mice on behavior and neurochemistry in adulthood. Mice were lesioned on PND 1 and tested at 8 weeks of age on a battery of behavioral tests including passive avoidance, cued and spatial tasks in the Morris water maze, simple and delayed nonmatch to sample versions of an odor discrimination task, and locomotor activity measurements. Following behavioral testing, mice were sacrificed for either morphological assessment or neurochemical analysis of a cholinergic marker or catecholamines. There were no lesion or sex differences in acquisition or retention of passive avoidance, performance of the odor discrimination tasks, or activity levels. Control mice showed a robust sex difference in performance of the spatial water maze task. The lesion produced a slight cued but more dramatic spatial navigation deficit in the water maze which affected only the male mice. Neurochemical analyses revealed no lesion-induced changes in either choline acetyltransferase activity or levels of norepinephrine or serotonin at the time of testing. The subsequent report shows a sex difference in lesion-induced changes in cortical morphology which suggests that sexually dimorphic cholinergic influences on cortical development are responsible for the behavioral deficits seen in this study. 相似文献
995.
Lactational function in the mammary epithelial cell is subject to complex regulation, most probably involving multiple extracellular and intracellular proteins that act at any of a number of levels. Although some of these proteins have been identified it is likely that additional controllers of lactation exist, but have yet to be discovered. In an effort to identify such proteins, a search was made for non-milk lactation-associated or prolactin-responsive proteins in primary mouse mammary epithelial cells and the mouse mammary epithelial cell line, COMMA-D using two-dimensional electrophoresis on large-format gels. These analyses revealed 12 proteins whose rate of synthesis was dependent on lactation state or on response to prolactin. Two of these (p77 and p63) were lactation-associated in primary cells and prolactin-responsive in COMMA-D cells. These two proteins were identified by amino acid sequencing as glucose-regulated protein 78 (GRP78) and protein disulphide isomerase (PDI). The localization of these proteins in the endoplasmic reticulum and their presence in other secretory cell types and tissues suggests that they have a function in the processing or secretion of milk proteins. 相似文献
996.
A common form of modified release is the encapsulation of specially formulated or coated pellets. An important first step in the development of a multiparticulate coated dosage form is to characterize the uncoated pellet. In earlier work, an uncoated pellet system developed in these laboratories and prepared from microcrystalline cellulose (MCC) was investigated and found to exhibit both the physical characteristics of an inert matrix and varying degrees of in vitro modified release. The use and characterization of MCC as a spheronization matrix material forms the basis for this formulation study. The drug release mechanism has been verified by varying selected formulation factors and evaluating the resulting pellets according to the relationship developed by T. Higuchi for granular inert matrices. In all cases, this MCC pellet system adhered to the theoretical relationships and the drug release mechanism can, therefore, be classified as an inert matrix. 相似文献
997.
The intensity of the immunohistochemical reaction (IIR) against the alpha species of protein kinase C (PKC) was quantified in the rod bipolar cells (RBC) of the goldfish retina using of image analysis. Retinae incubated in control Ringer solution showed similar IIR in both the soma and the axon terminal (IIR-ratio approximately 1). Activation of PKC induces the 'transport' of the enzyme to the synaptic terminal of RBC and an increase in the IIR-ratio. In the present report, the effect of retinal neurotransmitters on the IIR-ratio and the time course of PKC transport was studied. 相似文献
998.
JL Cloud RT Marconi CH Eggers CF Garon K Tilly DS Samuels 《Canadian Metallurgical Quarterly》1997,194(1):137-141
BACKGROUND: We studied the morphological changes occurring in neurons from the dorsal lateral geniculate nucleus (dLGN) during aging by analysing the size and shape of cell bodies and nuclei. METHODS: Male albino Wistar rats, aged 3, 18, 24, and 30 months, were used. After appropriate tissue preparation and following the usual histological procedure, the profiles of 1,920 neuronal bodies and nuclei were drawn using a camera lucida. Data was later recorded and processed with a semiautomatic image analyser. RESULTS AND CONCLUSIONS: We observed that dLGN neurons do not change in size from the age of 3-24 months. Between 24 and 30 months, the soma and nucleus of the cell undergo hypertrophy, 32.8% and 35.6%, respectively, when compared to those from 3-month-old animals (P < 0.01). Furthermore, we found a high correlation between cell body size/nucleus size, which does not disappear with age. The r values (correlation coefficient) were 0.7998, 0.8662, 0.8433 and 0.7304, and R2 (determination coefficient) was equal to 0.6397, 0.7504, 0.7112, and 0.5335. These latter values show that in 63.97%, 75.04%, 71.12%, and 53.35% of cases, respectively, modifications in somata size were accompanied by similar changes in nucleus size, and vice-versa. The study of the shape of the soma and nucleus of the cell revealed that both structures have a rounded-oval configuration that does not change in a significant way from adulthood to old age. 相似文献
999.
OBJECTIVES: To determine whether endothelin-1 (ET-1) in tracheal aspirates (TA) is a specific marker for acute lung injury in preterm infants with respiratory distress syndrome (RDS) who progress to bronchopulmonary dysplasia (BPD); and to investigate the relationship between TA ET-1 and the proinflammatory cytokines, interleukin-6 (IL-6) and IL-8, as early mediators of BPD. STUDY DESIGN: We measured TA ET-1, IL-6, and IL-8 levels in preterm infants whose lungs were mechanically ventilated for RDS, categorized into two groups, BPD or non-BPD, on the basis of oxygen requirement at 36 weeks' postconceptional age. RESULTS: A total of 106 TA samples were obtained from 34 infants with gestational ages ranging from 24 to 28 weeks on days 1, 3, 5, and 7 of life. There was a wide range of ET-1 concentration. TA ET-1 levels were significantly elevated on days 1, 3, and 7 in infants in whom BPD developed, in comparison with the non-BPD group (Mann-Whitney U test: p < 0.01). TA IL-8 levels were elevated on days 1, 3, 5, and 7 in the BPD group (p < 0.01); TA IL-6 levels were elevated (p < 0.05) only on day 5. There was a similarity in pattern of increase of TA ET-1 and TA IL-8 levels in the BPD group, with both being elevated in the first 24 hours of life and through the first week. There was no correlation between ET-1 and IL-8 values. CONCLUSION: Early significant increase in the TA ET-1 and IL-8 concentrations in preterm infants with acute lung injury correlates with subsequent progression to BPD. 相似文献
1000.
CF Heyns P van Vollenhoven JW Steenkamp FJ Allen DJ van Velden 《Canadian Metallurgical Quarterly》1997,80(2):307-312
OBJECTIVE: To determine the effect of double immunostaining in the differential diagnosis of the benign vs. malignant nature of breast lesions with fine needle aspiration results. STUDY DESIGN: The study group consisted of 26 samples aspirated from patients with borderline breast lesions. RESULTS: Direct immunostaining by means of monoclonal antibodies directed against individual intermediate filament proteins keratin 8 and 17 revealed that the percentage of K8+K17+ cells in material from patients with fibrocystic disease and fibroadenoma significantly exceeded that found in carcinoma specimens. The diagnoses were confirmed histologically. CONCLUSION: The quantitative method applied in the analysis of double-immunostained cytologic aspirates is recommended for the differential diagnosis of the benign vs. malignant nature of breast lesions in borderline cases. 相似文献