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131.
Yeung QS Briton-Jones CM Tjer GC Chiu TT Haines C 《Journal of assisted reproduction and genetics》2004,21(10):355-360
PURPOSE: To investigate whether commonly used test tube warming devices maintain a constant temperature in follicular fluid aspirates. METHODS: By using a digital thermocouple, temperature was measured and comparisons were made between an analog dry block heater, a digital dry block heater, and a thermostatic test tube heater. RESULTS: For small fluid volumes, temperature in the block heaters increased above 37 degrees C after being in the block for over 2 min. The thermostatic heater maintained a constant temperature, but this was below the factory setting of 36.9 degrees C. Temperature maintenance was influenced by fluid volume in each tube. CONCLUSIONS: One of the key factors in the handling of gametes and embryos is the maintenance of constant temperature. Test tube warming devices require verification of their ability to maintain fluid at the desired temperature. Temperature may vary with fluid volume and the type of test tube warming device used. 相似文献
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134.
Jun?Yang Scott?F.?Gallagher Krista?Haines P.?K.?Epling-Burnette Fenqi?Bai William?R.?GowerJr. Stephen?Mastorides James?G.?Norman Michel?M.?MurrEmail author 《Journal of gastrointestinal surgery》2004,8(2):166-174
Liver injury is an important prognostic indicator during acute pancreatitis. The aim of this study was to determine the role
of Fas ligand (FasL) in hepatocyte injury. Liver parenchymal enzymes were measured in cocultures of hepatocytes and Kupffer
cells treated with elastase. FasL and FasL mRNA were measured in elastase-treated Kupffer cells. Hepatocytes were treated
with FasL and their viability was assessed by monotetrazolium (MTT), apoptosis by flow cytometry, as well as caspase-3 and
p38-mitogen-activated protein kinase (MAPK) by immunoblotting. Elastase increased aspartate aminotransferase and lactate dehydrogenase
in cocultures of hepatocyte and Kupffer cells (P < 0.040). Elastase increased FasL production from Kupffer cells (P = 0.02)
and upregulated FasL mRNA (FasL/beta-2 microglobulin (BMG): 0.23 ± 0.03 vs. 0.11 ± 0.003; P = 0.04). FasL increased alanine
aminotransferase and lactate dehydrogenase (P < 0.03) and reduced hepatocyte viability by 45% (P = 0.01). FasL increased the
number of dually labeled cells with AnnexinV/7AAD (P = 0.03) while upregulating cleavage of caspase-3 and the phosphorylation
of p38-MAPK. FasL antibody attenuated the FasL-related increase in dually labeled cells (P = 0.02), the cleavage of caspase-3,
and phosphorylation of p38-MAPK. Pancreatic elastase upregulates FasL within Kupffer cells. FasL induces hepatocyte injury
and death and upregulates p38-MAPK and caspase-3 within hepatocytes. The ability to manipulate interactions between Kupffer
cells and hepatocytes may have important therapeutic implications.
Presented at the Forty-Fourth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Florida, May 18–21,
2003 (poster presentation) and published as an abstract in Gastroenterology 2003.
Supported by SSAT Career Development Award (M.M.), Dr. Bob Haines Pancreatitis Research Fund (M.M.), VA Merit Award (J.N.)
and a VA Merit Award (P.K.E.-B.). 相似文献
135.
Bentes de Souza AM Wang CC Chu CY Briton-Jones CM Haines CJ Rogers MS 《Human reproduction (Oxford, England)》2004,19(6):1281-1286
BACKGROUND: The objective of this study was to verify whether in vitro exposure of human peritoneal mesothelial cells to carbon dioxide (CO(2)) influences the levels of 8-isoprostaglandin F(2alpha) (8-iso-PGF(2alpha)), a marker of oxidative stress. METHODS: Mesothelial cells were exposed to either: (i). 100% CO(2) for 4 h; (ii). 100% helium (an alternative gas with which to create hypoxic conditions) for 4 h; (iii). 100% CO(2) for 24 h; or (iv). standard conditions (control). After gas exposure, mesothelial cells were returned to standard conditions and harvested immediately (T(0)), and at 1-(T(1)) and 3 (T(3)) h afterwards. Cell viability and culture medium pH were monitored throughout the experiments. 8-iso-PGF(2alpha) was assayed by enzyme-linked immunosorbent assay (ELISA). RESULTS: Exposure to CO(2) decreased the culture medium pH whereas helium increased the pH. 8-iso-PGF(2alpha) levels in all treated groups were significantly higher than in the control group: in the 4 h CO(2) group at T(1); in the 24 h CO(2) group at T(0) and T(1); and in the 4 h helium group at T(0), T(1) and T(3). 8-iso-PGF(2alpha) levels following 4 h CO(2) exposure were significantly lower than after 24 h CO(2) exposure at T(1), and lower than following 4 h helium exposure at all time points. CONCLUSIONS: Exposure to both CO(2) and helium induces oxidative stress in mesothelial cells. Hypoxia-reoxygenation may play a role in this process. 相似文献
136.
Rabionet R Jaworski JM Ashley-Koch AE Martin ER Sutcliffe JS Haines JL Delong GR Abramson RK Wright HH Cuccaro ML Gilbert JR Pericak-Vance MA 《Neuroscience letters》2004,372(3):209-214
Autism has a strong and complex genetic component, involving several genes. Genomic screens, including our own, have shown suggestive evidence for linkage over a 20-30 cM region on chromosome 2q31-q33. Two subsequent reports showed that the linkage evidence increased in the subset of families with phrase speech delay (PSD), defined as onset of phrase speech later than 3 years of age. To further investigate the linkage in the presumptive candidate region, microsatellite markers in a 2 cM grid covering the interval from 164 to 203 cM were analyzed in 110 multiplex (2 or more sampled autism patients) families. A maximum heterogeneity LOD (HLOD) score of 1.54 was detected at D2S1776 (173 cM) in the overall dataset (dominant model), increasing to 1.71 in the PSD subset. While not conclusive, these data continue to provide suggestive evidence for linkage, particularly considering replication by multiple independent groups. Positive LOD scores extended over the entire region, continuing to define a broad candidate interval. Association studies were performed on several functional candidates mapping within the region. These included GAD1, encoding GAD67, whose levels are reduced in autopsy brain material from autistic subjects, and STK17B, ABI2, CTLA4, CD28, NEUROD1, PDE1A, HOXD1 and DLX2. We found no evidence for significant allelic association between autism and any of these candidates, suggesting that they do not play a major role in the genetics of autism or that substantial allelic heterogeneity at any one of these loci dilutes potential disease-allele association. 相似文献
137.
OBJECTIVES/HYPOTHESIS: The treatment of anosmia has changed minimally since the early 1970s, despite dramatic advances in the understanding of the molecular biology of olfaction. Recent studies from the authors' laboratory have suggested that most common causes of clinical olfactory dysfunction, including rhinosinusitis, appear to be associated with increased apoptotic death of olfactory sensory neurons. This appears to result in a decline in the number of functioning mature olfactory sensory neurons, despite the capacity of the olfactory epithelium for regeneration. The current study evaluated the ability of the antibiotic minocycline to inhibit olfactory sensory neuron apoptosis. This drug is known to inhibit apoptosis separate from its anti-infective properties. Olfactory sensory neuron apoptosis was triggered by surgical deafferentation ("bulbectomy"), the standard experimental model. Earlier studies have indicated that bulbectomy and sinusitis invoke similar proteolytic enzyme cascades in olfactory sensory neurons. STUDY DESIGN: Histological analysis of animal olfactory tissue. METHODS: Mice underwent unilateral olfactory bulbectomy to induce apoptotic olfactory sensory neuron death, with and without 45 mg/kg intraperitoneal minocycline given 12 hours before surgery and every 12 hours until death. Mice were killed at 2 and 4 days after bulbectomy and assessed for activation of capsase-3 and olfactory sensory neuron survival by immunohistochemical analysis. RESULTS: Minocycline resulted in partial suppression of cell death at 2 days after surgery when compared with untreated animals. CONCLUSION: Minocycline inhibits olfactory sensory neuron death in the face of a potent pro-apoptotic stimulus. This drug is well tolerated and is currently undergoing human trials for the management of a variety of neurological disorders associated with apoptosis. The current results suggest that minocycline may be efficacious in the management of peripheral olfactory loss as well. 相似文献
138.
BACKGROUND: Extensive studies have revealed the importance of a healthy lifestyle and the role of each lifestyle factor in health. However, lifestyle factors have rarely been studied simultaneously. The authors propose an integrated approach to summarize total healthfulness of lifestyles and to enhance understanding of lifestyle patterns across countries. METHODS: The authors created an overall measure of lifestyle called the Lifestyle Index (LI), integrating diet, physical activity, smoking, and alcohol use to provide a global tool of monitoring healthfulness and patterns of lifestyles. Using the LI, the authors conducted a cross-national comparison between China (n = 8352) and the United States (n = 9750). RESULTS: The LI effectively reflected the healthfulness of lifestyle components in both countries. The mean of the LI scores was slightly higher in China than the US. Scores of diet quality, physical activity, and smoking were higher in China, but scores of alcohol behavior were higher in the US. Similar lifestyle patterns but different unhealthy behaviors were identified in these countries. CONCLUSIONS: An assessment of total healthfulness of lifestyles and a better understanding of lifestyle patterns across countries using the LI can provide practical guidance to developing and targeting public health promotion activities to improve global public health. 相似文献
139.
Nicodemus KK Stenger JE Schmechel DE Welsh-Bohmer KA Saunders AM Roses AD Gilbert JR Vance JM Haines JL Pericak-Vance MA Martin ER 《Neurogenetics》2004,5(4):201-208
Several recent case-control studies have examined the association between single nucleotide polymorphisms (SNPs) in the promoter region of the apolipoprotein E gene (APOE) and risk of Alzheimer disease (AD), with conflicting results. We assessed the relation between five APOE region SNPs and risk of AD in both case-control and family-based analyses. We observed a statistically significant association with the +5361T allele in the overall case-control analysis (P value=0.04) after adjusting for the known effect of the APOE-4 allele. Further analysis revealed this association to be limited to carriers of the APOE-4 allele. Age-stratified analyses in the patients with age at onset of 80 years or greater and age-matched controls showed that the –219T allele (P value=0.009) and the +113C allele (P value=0.03) are associated with increased risk of AD. Despite these findings, haplotype and family-based association analyses were unable to provide evidence that the APOE region SNPs influenced risk of AD independent of the APOE-4 allele. In addition to risk, we tested for association between the SNPs and age at onset of AD, but found no association in the case-control or family based analyses. In conclusion, SNPs +5361, or a SNP in strong linkage disequilibrium, may confer some additional risk for developing AD beyond the risk due to APOE-4; however, the effect independent of APOE-4 is likely to be small. 相似文献
140.