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901.
902.
Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder, commonly caused by a point mutation in the lamin A gene that results in a protein lacking 50 aa near the C terminus, denoted LADelta50. Here we show by light and electron microscopy that HGPS is associated with significant changes in nuclear shape, including lobulation of the nuclear envelope, thickening of the nuclear lamina, loss of peripheral heterochromatin, and clustering of nuclear pores. These structural defects worsen as HGPS cells age in culture, and their severity correlates with an apparent increase in LADelta50. Introduction of LADelta50 into normal cells by transfection or protein injection induces the same changes. We hypothesize that these alterations in nuclear structure are due to a concentration-dependent dominant-negative effect of LADelta50, leading to the disruption of lamin-related functions ranging from the maintenance of nuclear shape to regulation of gene expression and DNA replication.  相似文献   
903.

Background:

Nosocomial sepsis (NS) in newborns (NBs) is associated with high mortality rates and low microbial recovery rates. To overcome the latter problem, new techniques in molecular biology are being used.

Objectives:

To evaluate the diagnostic efficacy of SeptiFast test for the diagnosis of nosocomial sepsis in the newborn.

Materials and Methods:

86 blood specimens of NBs with suspected NS (NOSEP-1 Test > 8 points) were analyzed using Light Cycler SeptiFast (LC-SF) a real-time multiplex PCR instrument. The results were analyzed with the Roche SeptiFast Identification Software. Another blood sample was collected to carry out a blood culture (BC).

Results:

Sensitivity (Sn) and specificity (Sp) of 0.69 and 0.65 respectively, compared with blood culture (BC) were obtained for LC-SF. Kappa index concordance between LC-SF and BC was 0.21. Thirteen (15.11%) samples were BC positive and 34 (31.39%) were positive with LC-SF tests.

Conclusions:

Compared with BC, LC-SF allows the detection of a greater number of pathogenic species in a small blood sample (1 mL) with a shorter response time.  相似文献   
904.
905.
Antibodies to the AIDS retrovirus, specifically to human T cell lymphotropic virus, type III, and AIDS-associated retrovirus, were detected with increasing prevalence in a population of 190 hemophiliacs from western Pennsylvania between 1981 and 1984: 7.7% in 1981, 20.0% in 1982, 45.5% in 1983, and 62.5% in 1984. The seropositive included approximately three fourths of those receiving factor VIII concentrate, nearly one third of those receiving factor IX concentrate, nearly one fifth of those receiving cryoprecipitate, and none of those receiving fresh frozen plasma. The seroconversion rate, determined on 43 seropositive hemophiliacs from this group who were serially sampled, was 0% in 1977, 4.7% in 1978, 4.9% in 1979, 2.6% in 1980, 10.5% in 1981, 52.9% in 1982, 87.5% in 1983, and 100% in 1984. Of 27 seropositive for three or more years (since 1982 or before), four (15%) have developed AIDS and seven (26%), diffuse lymphadenopathy (ARC); of 16 seropositive for less than three years, none has developed AIDS and three (19%) have developed ARC. The mean time from seroconversion to onset of ARC, 0.8 +/- 0.2 years (SEM), was shorter (P less than .001) than the time to onset of AIDS, 4.1 +/- 0.6 years. These findings confirm the widespread presence of AIDS retrovirus and support the association of these retroviruses with the acquired immunodeficiency syndrome and related conditions.  相似文献   
906.
OBJECTIVE: To obtain data concerning a history of infection occurring in the 3 months before recognition of the typical weakness and rash associated with juvenile dermatomyositis (JDM). METHODS: Parents or caretakers of children within 6 months of JDM diagnosis were interviewed by the registry study nurse concerning their child's symptoms, environment, family background, and illness history. Physician medical records were reviewed, confirming the JDM diagnosis. RESULTS: Children for which both a parent interview and physician medical records at diagnosis were available (n = 286) were included. Diagnoses were as follows: definite/probable JDM (n = 234, 82%), possible JDM (n = 43, 15%), or rash only (n = 9, 3%). The group was predominantly white (71%) and had a girl:boy ratio of 2:1. Although the mean age at onset was 6.7 years for girls and 7.3 years for boys, 25% of the children were < or =4 years old at disease onset. In the 3 months before onset, 57% of the children had respiratory complaints, 30% had gastrointestinal symptoms, and 63% of children with these symptoms of infection were given antibiotics. CONCLUSION: This study provides evidence that JDM affects young children. The symptoms of the typical rash and weakness often follow a history of respiratory or gastrointestinal complaints. These data suggest that the response to an infectious process may be implicated in JDM disease pathogenesis.  相似文献   
907.
908.
909.
The objective of this study was to analyze the healthcare encounters between nurses and parents of different cultural backgrounds in primary health care. An ethnographic study was carried out using participant observations in health centers and interviews with nurses. Data were analyzed using thematic content analysis and constant comparative method. Four main themes were identified when nurses met parents of other cultural backgrounds: lack of mutual understanding, electronic records hamper the interaction, lack of professionals' cultural awareness and skills, and nurses establish superficial or distant relationships. The concepts of ethnocentrism and cultural imposition are behind these findings, hampering the provision of culturally competent care in primary health services. There were difficulties in obtaining and registering culturally related aspects that influence children's health and development. This was due to e‐records, language barriers, and the lack of cultural awareness and skills in health professionals making the encounters difficult for both nurses and parents. These findings show that there is a clear threat for health equity and safety in primary care if encounters between nurses and parents do not improve to enable nursing care to be tailored to any individual family needs.  相似文献   
910.

Background/Objectives:

Individually, genetic variants only moderately influence cardiometabolic (CM) traits, such as lipid and inflammatory markers. In this study we generated genetic risk scores from a combination of previously reported variants influencing CM traits, and used these scores to explore how adiposity levels could mediate genetic contributions to CM traits.

Subjects/Methods:

Participants included 1649 women from the 2005 Cebu Longitudinal Health and Nutrition Survey. Three genetic risk scores were constructed for C-reactive protein (CRP), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TGs). We used linear regression models to assess the association between each genetic risk score and its related trait. We also tested for interactions between each score and measures of adiposity.

Results:

Each genetic risk score explained a greater proportion of variance in trait levels than any individual genetic variant. We found an interaction between the TG genetic risk score (2.29–14.34 risk alleles) and waist circumference (WC) (Pinteraction=1.66 × 10−2). Based on model predictions, for individuals with a higher TG genetic risk score (75th percentile=12), having an elevated WC (⩾80 cm) increased TG levels from 1.32 to 1.71 mmol l−1. However, for individuals with a lower score (25th percentile=7), having an elevated WC did not significantly change TG levels.

Conclusions:

The TG genetic risk score interacted with adiposity to synergistically influence TG levels. For individuals with a genetic predisposition to elevated TG levels, our results suggest that reducing adiposity could possibly prevent further increases in TG levels and thereby lessen the likelihood of adverse health outcomes such as cardiovascular disease.  相似文献   
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