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1.

Background  

Placental and fetal growth requires high rates of cellular turnover and differentiation, which contributes to conceptus development. The trophoblast has unique properties and a wide range of metabolic, endocrine and angiogenic functions, but the proliferative profile of the bovine placenta characterized by flow cytometry analysis and its role in fetal development are currently uncharacterized. Complete understanding of placental apoptotic and proliferative rates may be relevant to development, especially if related to the pathogenesis of pregnancy losses and placental abnormalities.  相似文献   
2.
Previous studies indicate that astrocytes are the brain cells that express acidic fibroblast growth factor (aFGF) and that the expression is increased upon activation. However, there has been no study investigating the significance of this phenomenon. Here we report that aFGF treatment of IFNγ-stimulated human astrocytes, and LPS/IFNγ-stimulated human microglia, enhances their secretion of inflammatory cytokines and other materials toxic to human neuroblastoma SH-SY5Y cells. The mechanism of aFGF enhancement involves stimulation of the receptor FGFR2 IIIb. We show by RT-PCR that this receptor, but not other FGF receptors, is robustly expressed by astrocytes and microglia. We establish by Western blotting, and immunohistochemistry on postmortem human brain tissue that the FGFR2 IIIb protein is expressed by both of these glial cell types. We blocked the inflammatory stimulant action of aFGF by transfecting microglia and astrocytes with a small inhibitory RNA (siRNA) to FGFR2 IIIb as well as by removal of aFGF using an anti-aFGF antibody. Treatment with bFGF in combination with the stimulants was without effect, but together with aFGF, it partially counteracted the action of aFGF, indicating that it may be a weak antagonist of FGFR2 IIIb. The inflammatory effect was also attenuated by treatment with inhibitors of protein kinase C, Src tyrosine kinase, and MEK-1/2 indicating the involvement of these intracellular pathways. Our data suggest that inhibition of expression or release of aFGF could have therapeutic potential by inhibiting inflammation in neurodegenerative diseases such as Alzheimer disease where many neuroinflammatory molecules are prominently expressed.  相似文献   
3.
—Tyrosine hydroxylase (TH), dopa decarboxylase (DDC), glutamic acid decarboxylase (GAD), choline acetyltransferase (CAT), and acetylcholinesterase (AChE) were measured in 18–55 areas of brain from humans post mortem. Individuals meeting sudden and unexpected death (22), patients dying in hospital with non–neurological illness (6), Parkinson's disease (12), Huntington's chorea (8), terminal coma (6) or head injury (2) were included in the series. The absolute values obtained compared favourably with some previous human studies where high values for these enzymes were obtained, as well as with monkey and baboon data. The regional distributions of the enzymes were also comparable to those previously reported in human and animal studies. A number of important points with regard to human tissue seemed to emerge from the study. The mode of death was not a factor in enzyme levels in non–neurological and non-coma cases. Post mortem delay did not seem to be a major factor either even though a substantial decline in GAD, TH and DDC could be demonstrated in rats left several hours between sacrifice and removal of the brain for assay. Age had a highly significant effect in certain areas of brain. The decline typically followed a curvilinear pattern (activity = A/age + B with the sharpest drops being in the younger age groups). DDC seemed to be the enzyme most severely affected by age but all the enzymes showed declines in certain brain areas, while in other areas there was no significant decline. All the enzymes were very depressed by coma from illness except AChE. TH and DDC in the brain stem were, however, not affected in the head injury cases. The Parkinsonian cases showed a sharply decreased TH activity in the substantia nigra, caudate and putamen. There were decreases in GAD in the globus pallidus (GP) and substantia nigra with marginal decreases in the neostriatum. CAT levels in the extrapyramidal nuclei were normal. In Huntington's chorea there was a substantial decrease in GAD in all the extrapyramidal structures. There was a patchy loss of CAT in the neostriatum and locus coeruleus.  相似文献   
4.
Atlantic salmon embryos and alevins Salmo salar that had been exposed to isosorbide dinitrate (ISDN) for 4 weeks, on transfer to fresh water, showed an increase in heart rate. Unexposed embryos and alevins showed a decrease in heart rate following transfer to 100 μmol l−1 ISDN for 4 h. This is in contrast to adult rainbow trout and higher vertebrates where tachycardia occurred in response to nitric oxide (NO) donors. The decreased heart rate in response to ISDN was inhibited by 2 mg 1−1 methylene blue, indicating that NO activates cardiovascular events via guanylyl cyclase and cyclic guanidine monophosphate. Heart rate of rainbow trout alevins Oncorhynchus mykiss exposed to 100 μmol l−1 aminoguanidine responded with a slowly developed but significant bradycardia over 10 min as did those reared in aminoguanidine for 4 weeks then transferred to fresh water. A potentiated increase in heart rate on exposure to the NO donor sodium nitroprusside (SNP), occurred within 1 min in salmon alevins reared in l -nitro-arginine methyl ester ( l -NAME) for 4 weeks, indicating up-regulation of NO receptors. The evidence for down-regulation of SNP-reared alevins exposed to l -NAME was less well defined. The results suggest that both salmonid embryos and alevins have a functional l -arginine-NO pathway and that NO has a physiological role in control of cardiovascular events.  相似文献   
5.
This investigation examined the effect of preconditioning in an in vivo model of ischemia-reperfusion injury. Anesthetized New Zealand White rabbits underwent 30 min of regional myocardial ischemia followed by 2 h of reperfusion. Hearts preconditioned with two cycles of 5 min ischemia-10 min reperfusion (IPC) or with the ATP-sensitive K (K(ATP)) channel opener, diazoxide (10 mg/kg), exhibited significantly (P < 0.05) smaller infarcts compared with control. These treatments also significantly (P < 0.001 to P < 0.05) reduced C1q, C1r, C3, C8, and C9 mRNA in the areas at risk (AAR). The K(ATP) channel blocker 5-hydroxydecanoate (5-HD; 10 mg/kg) attenuated infarct size reduction elicited by IPC and diazoxide treatment. 5-HD partially reversed the decrease in complement expression caused by IPC but not diazoxide. There were no significant differences in complement gene expression in the nonrisk regions and livers of all groups. Western blot analysis revealed that IPC also reduced membrane attack complex expression in the AAR. The data demonstrate that preconditioning significantly decreases reperfusion-induced myocardial complement expression in vivo.  相似文献   
6.
  总被引:1,自引:0,他引:1  
  相似文献   
7.
8.
Intrastriatal injections of kainic acid are known to destroy striatal neurons including many containing choline acetyltransferase (CAT) and glutamic acid decarboxylase (GAD). Using these enzymes as indices of neuronal loss, the neurotoxicity of small doses of kainic acid was found to be influenced by injection time and volume. It was partly blocked by coninjection of some but not all glutamate antagonists or by prior lesioning of the corticostriatal tract. Other adjuvants, drugs, or lesions tested had little modifying effect, except that changes in the dopaminergic system seemed to increase the toxicity towards cholinergic but not GABAnergic systems. High-affinity glutamate accumulation by neostriatal synaptosomes was significantly increased 1–7 days following kainic acid injections. MAO and acetylcholinesterase activities were depressed in kainic acid-lesioned striata but not nearly as much as were CAT and GAD. An indirect mechanism involving glutamate release and inhibition of reuptake is suggested for kainic acid neurotoxicity.  相似文献   
9.

Background

This study assessed the short and the long term safety of the 2009 AS03 adjuvanted monovalent pandemic vaccine through an active web-based electronic surveillance. We compared its safety profile to that of the seasonal trivalent inactivated influenza vaccine (TIV) for 2010–2011.

Methodology/Principal Findings

Health care workers (HCW) vaccinated in 2009 with the pandemic vaccine (Arepanrix ® from GSK) or HCW vaccinated in 2010 with the 2010–2011 TIV were invited to participate in a web-based active surveillance of vaccine safety. They completed two surveys the day-8 survey covered the first 7 days post-vaccination and the day-29 survey covered events occurring 8 to 28 days after vaccination. Those who reported a problem were called by a nurse to obtain details. The main outcome was the occurrence of a new health problem or the worsening of an existing health condition that resulted in a medical consultation or work absenteeism. For the pandemic vaccine, a six-month follow-up for the occurrence of serious adverse events (SAE) was conducted. Among the 6242 HCW who received the pandemic vaccine, 440 (7%) reported 468 events compared to 328 of the 7645 HCW (4.3%) who reported 339 events after the seasonal vaccine. The 2009 pandemic vaccine was associated with significantly more local reactions than the 2010–2011 seasonal vaccine (1% vs. 0.03%, p<0.001). Paresthesia was reported by 7 HCW (0.1%) after the pandemic vaccine but by none after the seasonal vaccine. For the pandemic vaccine, no clustering of SAE was found in the 6 month follow-up.

Conclusion

The 2009 pandemic vaccine seems to have a good safety profile, similar to the 2010–2011 TIV, with the exception of local reactions. This surveillance was adequately powered to identify AE associated with an excess risk ≥1 per 1000 vaccinations but is insufficient to detect rare AE.

Trial Registration

ClinicalTrials.gov NCT01289418, NCT01318876  相似文献   
10.

Background

Working in healthcare is often considered a risk factor for influenza; however, this risk has not been quantified. We aimed to systematically review evidence describing the annual incidence of influenza among healthy adults and healthcare workers (HCWs).

Methods and Findings

We searched OVID MEDLINE (1950 to 2010), EMBASE (1947 to 2010) and reference lists of identified articles. Observational studies or randomized trials reporting full season or annual influenza infection rates for healthy, working age adult subjects and HCWs were included. Influenza infection was defined as a four-fold rise in antibody titer, or positive viral culture or polymerase chain reaction.From 24,707 citations, 29 studies covering 97 influenza seasons with 58,245 study participants were included. Pooled influenza incidence rates (IR) (95% confidence intervals (CI)) per 100 HCWs per season and corresponding incidence rate ratios (IRR) (95% CI) as compared to healthy adults were as follows. All infections: IR 18.7 (95% CI, 15.8 to 22.1), IRR 3.4 (95% CI, 1.2 to 5.7) in unvaccinated HCWs; IR 6.5 (95% CI, 4.6 to 9.1), IRR 5.4 (95% CI, 2.8 to 8.0) in vaccinated HCWs. Symptomatic infections: IR 7.5 (95% CI, 4.9 to 11.7), IRR 1.5 (95% CI, 0.4 to 2.5) in unvaccinated HCWs, IR 4.8 (95% CI, 3.2 to 7.2), IRR 1.6 (95% CI, 0.5 to 2.7) in vaccinated HCWs.

Conclusions

Compared to adults working in non-healthcare settings, HCWs are at significantly higher risk of influenza.  相似文献   
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