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321.
322.
A passive latex agglutination (PLA) test for cytomegalovirus (CMV) antibody detection has been shown to be an acceptable method of screening both donor sera and plasma from units of red cells and platelets stored in CPDA-1. However, most plateletpheresis concentrates are collected in ACD, and CMV antibody testing of ACD-stored products has not been systematically evaluated by PLA. Sera and ACD-stored platelet concentrate bag segments from 104 donors were tested by PLA and by a solid-phase fluorescence immunoassay (FIAX) as a reference standard for CMV-IgM and CMV-IgG antibodies. Sera were stored at both 4 and 22 degrees C and were tested on Days 1 and 5 of storage; segments were tested daily for 5 days. Of 63 donor samples (61%) that tested negative for CMV-IgG by FIAX, there were two false-positive results in bag segments by PLA testing, one on Day 1 and the other on Day 2 of storage. PLA testing was consistently positive in sera and segments in the 40 donors (38%) who tested positive for CMV-IgG by FIAX. Potential false-negative PLA results occurred in five bag segments derived from one donor whose serum gave equivocal CMV-IgG results on FIAX. The sensitivity and specificity of the PLA assay were 100 percent for donor sera tested at both 4 and 22 degrees C and 91.5 and 98.4 percent, respectively, for platelet bag segment tests. Although no donors positive for CMV-IgM were identified, 15 (14.4%) had equivocal IgM anti-CMV test results.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
323.

Purpose

This study was undertaken to determine the neuroprotective effect of granulocyte stimulating factor (G-CSF) on neonatal hypoxic-ischemic brain injury.

Materials and Methods

Seven-day-old male newborn rat pups were subjected to 110 minutes of 8% oxygen following a unilateral carotid artery ligation. Apoptosis was identified by performing terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining and flow cytometry with a combination of fluorescinated annexin V and propidium iodide (PI) and JC-1 (5,5'',6,6''-tetrachloro-1,1'',3,3''-tetraethylbenzimidazolyl-carbocyanine iodide). The extent of cerebral infarction was evaluated at 2 weeks after recovery.

Results

With a single dose (50 µg/ kg) of G-CSF treatment immediately after hypoxic-ischemic insult, hypoxia-ischemia induced increase in TUNEL-positive cells, annexinV+/PI-and JC-1 positive apoptotic cells in the ipsilateral cerebral cortex was significantly reduced at 24 hours, measured by flow cytometry, and the extent of cerebral infarction at 2 weeks after recovery was also significantly attenuated compared to the hypoxia-ischemia control group.

Conclusion

Our data suggest that G-CSF is neuroprotective by inhibiting apoptosis, thereby reducing the ensuing cerebral infarction in a newborn rat pup model of cerebral hypoxia-ischemia (HI).  相似文献   
324.
The aim of this study was to investigate the effect of erythropoietin (EPO) on histological brain injury, subventricular zone (SVZ) expansion, and sensorimotor function deficits induced by hypoxia-ischemia (HI) in newborn rat pups. Seven-day-old male rat pups were divided into six groups: normoxia control, normoxia EPO, hypoxia control, hypoxia EPO, HI control, and HI EPO group. Sham surgery or HI was performed in all animals. HI was induced by ligation of the right common carotid artery followed by 90 min of hypoxia with 8% oxygen. Recombinant human EPO 3 U/g or saline was administered intraperitoneally, immediately, at 24- and 48-hr after insult. At two weeks after insult, animals were challenged with cylinder-rearing test for evaluating forelimb asymmetry to determine sensorimotor function. All animals were then sacrificed for volumetric analysis of the cerebral hemispheres and the SVZ. The saline-treated HI rats showed marked asymmetry by preferential use of the non-impaired, ipsilateral paw in the cylinder-rearing test. Volumetric analysis of brains revealed significantly decreased preserved ipsilateral hemispheric volume and increased ipsilateral SVZ volume compared with the sham-operated animals. Treatment of EPO significantly improved forelimb asymmetry and preserved ipsilateral hemispheric volume along with decreased expansion of ipsilateral SVZ following HI compared to the saline-treated HI rats. These results support the use of EPO as a candidate drug for treatment of neonatal hypoxic-ischemic brain damage.  相似文献   
325.

Ethnopharmacological relevance

Myrsine seguinii H. LÉVEILLÉ (syn. Rapanea neriifolia) (Myrsinaceae) is a medicinal plants traditionally used in Myanmar to treat infectious and inflammatory diseases. Since none of reports have systematically demonstrated the anti-inflammatory activity of this plant, we aimed to mechanistically understand the regulatory roles of the plant in inflammatory responses using the ethanolic extract of Myrsine seguinii (Ms-EE).

Materials and methods

Activated macrophages and peritonitis symptoms induced by lipopolysaccharide (LPS) were employed. HPLC analysis was used to identify active components. To characterize direct target enzymes, kinase assay was established.

Results

Ms-EE inhibited the production of nitric oxide (NO) and prostaglandin (PG)E2 in RAW264.7 cells and peritoneal macrophages stimulated by LPS. This extract suppressed the mRNA expression of the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 genes by down-regulating the activation of nuclear factor (NF)-κB and activator protein (AP-1). Interestingly, it was found that Ms-EE can directly suppress the enzyme activities of Syk, Src, and interleukin-1 receptor-associated kinase-1 (IRAK-1). Similarly, orally administered Ms-EE inhibited the phosphorylation of Src and Syk in peritoneal exudate-derived cells prepared from peritonitis. Finally, HPLC analysis clearly demonstrated that quercetin is a major active component with suppressing activity on the release of inflammatory mediators (NO and PGE2), and the enzyme activities of Src, Syk, and IRAK-1.

Conclusion

Ms-EE containing quercetin negatively modulates macrophage-mediated in vitro inflammatory responses and LPS-induced peritonitis by blocking the Src/Syk/NF-κB and IRAK-1/AP-1 pathways, which contributes to its major ethnopharmacological use as an anti-inflammatory herbal medicine.  相似文献   
326.
[Purpose] The purposes of this study were to assess the fundamental motor skill (FMS) of children with Down syndrome (DS) and to compare their FMS proficiencies to those of chronological age-matched and gender-matched typically developing children (TDC). [Participants and Methods] This cross-sectional study involved a total of 60 participants (30 children with DS and 30 TDC). The FMS proficiency of participants was assessed by using the test of gross motor development, second edition (TGMD-2). The data were analyzed using independent samples t-tests to verify the differences between the two groups and gender. The effect size of Cohen’s d was also determined for comparing the two groups. [Results] The results showed that there were significant differences between children with DS and the TDC on locomotor and object control standard scores, and the gross motor quotient (GMQ). However, there were no significant gender-based differences in the locomotor and object control standard scores and the GMQ in both groups. [Conclusion] Based on the current results, the FMS proficiency of children with DS is lower than the TDC. Therefore, a therapeutic intervention program is necessary for children with DS to improve their FMS proficiency.  相似文献   
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