Genetic characterization of bovine viral diarrhea virus strains in Beijing, China and innate immune responses of peripheral blood mononuclear cells in persistently infected dairy cattle

To acquire epidemiological data on the bovine viral diarrhea virus (BVDV) and identify cattle persistently infected (PI) with this virus, 4,327 samples from Holstein dairy cows were screened over a four-year period in Beijing, China. Eighteen BVD viruses were isolated, 12 from PI cattle. Based on genetic analysis of their 5'-untranslated region (5'-UTR), the 18 isolates were assigned to subgenotype BVDV-1m, 1a, 1d, 1q, and 1b. To investigate the innate immune responses in the peripheral-blood mononuclear cells of PI cattle, the expression of Toll-like receptors (TLRs), RIG-I-like receptors, interferon-alpha (IFN-alpha), IFN-beta, myxovirus (influenza virus) resistance 1 (MX1), and interferon stimulatory gene 15 (ISG15) was assessed by qPCR. When compared with healthy cattle, the expression of TLR-7, IFN-alpha, and IFN-beta mRNA was downregulated, but the expression of MX1 and ISG-15 mRNA was upregulated in PI cattle. Immunoblotting analysis revealed that the expression of interferon regulatory factor 3 (IRF-3) and IRF-7 was lower in PI cattle than in healthy cattle. Thus, BVDV-1m and 1a are the predominant subgenotypes in the Beijing region, and the strains are highly divergent. Our findings also suggest that the TLR-7/IRF-7 signaling pathway plays a role in evasion of host restriction by BVDV.

H2 receptor mediates the protective effect of histamine against the cellular edema and viability reduction induced by oxygen-glucose deprivation in rat hippocampal slices / 药学学报

<p><b>AIM</b>To determine the effect of histamine on ischemia-induced cellular edema and viability reduction in rat hippocampal slices, and the involved subtypes of histamine receptor in this effect.</p><p><b>METHODS</b>In vitro ischemic injury of hippocampal slices was induced by oxygen-glucose deprivation (OGD). The slice injury was determined by real-timely measuring the changes of light transmittance (LT) for the cellular edema in CA1 region of the hippocampal slice, and by detecting the product of 2, 3, 5-triphenyltetrazolium chloride (TTC), formazan, for the slice viability. The effect of histamine at various concentrations on the slice injury was observed, and the blockage by antagonists of histamine receptors was also investigated.</p><p><b>RESULTS</b>Histamine (0.01-10 micromol x L(-1)) inhibited the peak value of LT during OGD in hippocampal slices and improved the reduced viability after OGD. Diphenhydramine (0.1-10 micromol x L(-1)), an H1 receptor antagonist, did not affect the effect of histamine, while cimetidine (0.1-10 micromol x L(-1)), an H2 receptor antagonist, partly abolished the protective effect of histamine.</p><p><b>CONCLUSION</b>Histamine protects hippocampal slices against ischemia-induced cellular edema and viability reduction; this effect might be mediated via, at least partly, H2 receptor.</p>

Incomplete protective effects of minocycline on traumatic brain injury in rats and mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate protective effect of minocycline,a semisynthetic tetracycline derivative on different traumatic brain injuries in rats and mice.</p><p><b>METHODS</b>The opened brain trauma was induced in rats and the closed head injury and cold brain injury were induced in mice. In 3 brain trauma models, minocycline (45 mg/kg, ip) was administered twice daily for 2 d before the operation, at 30 min before and 1 h after the operation, and once daily for 2 d following the operation (totally 8 doses in 5 d). After the operation, the behavioral alteration was observed daily, lesion area and survival neuron density were measured at the end of the experiments (14 d after the injuries).</p><p><b>RESULT</b>For rat opened traumatic injury, minocycline promoted the recovery of hindlimb motor activity (inclined board angle), but did not alter other indexes. For mouse closed head traumatic injury, minocycline reduced the neuron loss, but did not improve behavioral dysfunction. For mouse cold injury-induced trauma, minocycline reduced death rate and lesion area, but did not remarkably improve behavior and neuron loss.</p><p><b>CONCLUSION</b>Minocycline only has an incomplete neuroprotective effect on different brain traumatic injuries in rats and mice.</p>

Effects of edaravone, minocycline and ONO-1078 on oxygen/glucose deprivation-induced electrophysiological alteration in rat hippocampal slices / 药学学报

<p><b>AIM</b>To establish an in vitro model of hippocampal slice to detect electrophysiological alteration after oxygen/glucose deprivation (OGD), and to observe the effects of edaravone, minocycline and ONO-1078 [pranlukast, 4-oxo-8-[p-(4-phenylbutyloxy) benzoyl-amino]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate].</p><p><b>METHODS</b>Hippocampal slices from rats were perfused with artificial cerebrospinal fluid lacking oxygen and glucose for 3, 4, 7 and 10 min. The population spike (PS) was recorded, and 2,3,5-triphenyltetrazolium chloride (TTC) staining was performed in some experiments, to detect the slice viability in the presence or absence of drugs in the perfusion solution.</p><p><b>RESULTS</b>Four min of OGD treatment was the most suitable duration for induction of slice injury, and PS amplitudes were recovered to (29 +/- 6)% of baseline values within 1 h after 4 min OGD. Edaravone, a free radical scavenger, at 1 and 10 mumol.L-1 significantly increased the recovery rate to (56 +/- 13)% and (69 +/- 12)% of baseline respectively 1 h after OGD. However, the anti-inflammatory drug minocycline (10 mumol.L-1) and leukotriene receptor antagonist ONO-1078 (1 mumol.L-1) did not increase the recovery. NMDA receptor antagonist ketamine, as a positive control, also promoted the recovery concentration-dependently.</p><p><b>CONCLUSION</b>OGD for 4 min was a feasible in vitro ischemia model for determination on electrophysiological alteration in hippocampal slices. Edaravone showed concentration-dependent protective effect on OGD injury, and anti-inflammatory drugs minocycline and ONO-1078 showed no effect.</p>

Protective effect of minocycline on oxygen/glucose deprivation and NMDA-induced neurotoxicity in rat primary neurons and hippocampal slices / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To develop oxygen/glucose deprivation (OGD)-and NMDA-induced neurotoxicity models in rat primary neurons and hippocampal slices, and to determine the protective effect of minocycline.</p><p><b>METHODS</b>The injuries of primary neurons were induced by OGD or NMDA (50micromol/L). Morphological changes of neurons were observed, and neuron viability was evaluated by MTT assay. The changes of light transmittance (LT) were induced by OGD or NMDA in rat hippocampal slices. The effects of minocycline and MK-801, an NMDA receptor antagonist, were observed in the models of OGD-or NMDA-induced injuries.</p><p><b>RESULT</b>Minocycline concentration dependently inhibited OGD induced decrease of neuron viability and ameliorated neuron morphological changes at 1 and 10 micromol/L. It also inhibited NMDA insult at 10 and 100 micromol/L. MK-801 inhibited both injuries at 1 micromol/L. However, minocycline at 1 or 10 micromol/L did not inhibit the augment of LT in hippocampal slices induced by OGD or NMDA, while MK-801 inhibited both OGD-and NMDA-induced LT augments.</p><p><b>CONCLUSION</b>Minocycline protects neurons from OGD insult, which may inhibit NMDA receptor-mediated neurotoxicity through an indirect pathway, but has no effect on OGD-or NMDA-induced immediate injury in hippocampal slices.</p>

Novel quantitative method for evaluating oxygen/glucose deprivation-induced injury of hippocampal slices / 浙江大学学报·医学版

OBJECTIVE: To establish a simple, sensitive in vitro method to evaluate oxygen/glucose deprivation (OGD)-induced injury of brain hippocampal slices in rats. METHODS: Rat hippocampal slices were incubated in 2% 2, 3, 5-triphenyltetrazolium chloride (TTC) solution after oxygen/glucose deprivation. They were then soaked in a measured volume of ethanol and dimethylsulfoxide (50:50) to extract the TTC formazan Product which was then measured by spectrophotometry. OGD induced LDH release was simultaneously measured. RESULTS: Progressive prolongation of OGD induced hippocampal injury resulted in decreased formazan coloration as determined by spectrophotometry. There was a parallel increase in LDH release, thus a negative correlation in these two products was noted. (r=-0.933,P <0.01). The injury was attenuated in the brain slices pre-treated with nimodipine, dexamethasone, and ketamine, but not ONO-1078. CONCLUSION: Solvent extraction and spectrophotometric quantification of formazan represents an objective measurement of OGD-induced injury of rat hippocampal slices.

Optical recording method for evaluation of neuronal damage in rat hippocampal slices during ischemia and reperfusion / 浙江大学学报·医学版

OBJECTIVE: To develop a novel technique of optical recording and its validation for assessment of the neuroprotective effect of nimodipine, a L-type calcium channel blocker. METHODS: In vitro ischemia was induced by oxygen/glucose deprivation (OGD), the light transmittance (LT) of rat hippocampal slices undergoing OGD and reperfusion was quantitated using a simple apparatus relying on basic principles of light transmittance and a computerised image analysis system. RESULTS: OGD was associated with increased LT in the stratum radiatum of CA1 area and the dentate gyrus in hippocampal slices. Peak LT occurred (7.59 +/-1.42) min after OGD, followed by a marked decrease in LT (n=15 slices). Nimodipine administration (0.5 &mgr;mol/L, n=10 slices, 5 &mgr;mol/L, n=9 slices) appeared to protect the tissue from OGD damage by inhibiting elevation of LT, However, 50 &mgr;mol/L nimodipine resulted in increased LT (25.83 +/-6.32). min after administration (n=11 slices). CONCLUSION: LT signal measurement is a non-invasive, reliable method for determination of neuronal damage in ischemic rat brain slices Nimodipine is demonstrated opposite neuroprotective effects depending on its dose.