神经节苷脂对脑瘫大鼠大脑皮质区Nestin、NGF表达的影响

目的 观察神经节苷脂(GM1)对脑瘫大鼠大脑皮质区神经巢蛋白(Nestin)、神经生长因子(NGF)表达的影响,探讨GM1促进脑瘫神经修复的可能机制.方法 选择出生10周雄性SD大鼠200只,随机分为3组:假手术组60只,脑瘫模型140只,再分为模型组70只,腹腔注射生理盐水;GM1组70只,腹腔注射GM1.分别在术后0～24 h的7个时间点利用酶联免疫法检测大鼠大脑皮质区Nestin、NGF表达情况,并在实验前和后1～4 d观察大鼠的体质量变化情况.结果 (1)大鼠大脑皮质区Nestin表达GM1组0～24 h、模型组0～12 h明显高于假手术组(P＜0.01);GM1组16～24 h明显高于模型组(P＜0.01).(2)GM1组大鼠大脑皮质区NGF表达0～24 h明显高于模型组(P＜0.05)和假手术组(P＜0.01).模型组NGF表达仅0、4、8h高于假手术组(P＜0.05).(3)GM1组术后第1、2天体质量缓慢增加,至第3、4天明显高于模型组(P＜0.05),接近假手术组(P＞0.05),模型组体质量增加不明显.结论 预防性使用GM1是通过增强大脑皮质的Nestin和NGF表达并延长表达时间来发挥其对实验性脑瘫大鼠的神经保护作用.     

Relationship between rate of infection and markers of inflammation/immunity in Holy Birman cats with feline coronavirus

The aim of this study was to assess whether Holy Birman cats (HB) have a peculiar immune profile and a higher rate of infection by feline coronaviruses (FCoV). Leucocyte and lymphocyte subsets, antibody titers, α₁-acid glycoprotein (AGP), globulin fractions, IL-4, IL-12 and IFN-γ in blood and fecal FCoV excretion were determined in HB (n = 75) and in cats from other breeds (n = 94). Significantly higher CD4/CD8 ratio, IFN-γ concentration and IL12/IL4 ratio and significantly lower IL-4 concentration and proportion of shedders were found in HB than in other breeds. No other differences were found. In conclusion, this study did not provide evidence of peculiar immune profiles in HB, except for a prevalent Th1 profile, that may explain why in our caseload the rate of shedders was lower in HB than in other breeds.     

VH1-44 gene usage defines a subset of canine B-cell lymphomas associated with better patient survival

The use of specific immunoglobulin heavy chain variable region (VH) genes has been associated with increased patient survival in human B-cell lymphomas (hBCL). Given the similarity of human and canine BCL (cBCL) in morphology and clinical treatment, we examined the choice of VH in cBCL and determined whether VH gene selection was a distinct feature associated with survival time in dogs. VH gene selection and mutational status in 52 cBCL, including 29 diffuse large B-cell lymphomas (cDLBCL, the most common subtype of cBCL), were analyzed by comparison with the 80 published canine germline VH gene sequences. We further examined the prognostic impact of the subgroups defined by these features on canine survival. We found that VH1-44 was preferentially expressed in the majority of the 52 cBCLs (60%) as well as in the majority of the cDLBCL subset (59%). VH1-44 gene expression was associated with a statistically better overall survival (p = 0.039) in cBCL patients, as well as in the cDLBCL subset of patients (p = 0.038). These findings suggest that VH gene selection in cBCL is not random and may therefore have functional implications for cBCL lymphomagenesis, in addition to being a useful prognostic biomarker.     

Up-regulated expression of PD-1 and its ligands during acute Classical Swine Fever virus infection in swine

In order to investigate the relationship between the PD-1 pathway and impairment of immune responses with the CSFV infection, the mRNA expression of PD-1 and its ligands were evaluated by quantitative polymerase chain reaction (qPCR) during artificial CSFV infection. Simultaneously, expression of IL-2 and IL-10 mRNA were detected. The T cell proliferation and CSFV load in plasma were also measured. Results showed that the expression of PD-1 and its ligands mRNA were significantly increased (p < 0.01) in PBMC from 3 to 7 days post infection (dpi). Meanwhile the level of IL-10 was up-regulated (p < 0.01). The IL-2 mRNA was not obviously changed but it is significantly increased from 14 dpi. The T cell proliferation was notably decreased at 7 dpi. The CSFV load was also increased in plasma. Overall, our results suggest that the expression of PD-1 and its ligands were up-regulated and probably correlated with immune inhibition during acute CSFV infection.     

Zero-inflated models for identifying disease risk factors when case detection is imperfect: Application to highly pathogenic avian influenza H5N1 in Thailand

Logistic regression models integrating disease presence/absence data are widely used to identify risk factors for a given disease. However, when data arise from imperfect surveillance systems, the interpretation of results is confusing since explanatory variables can be related either to the occurrence of the disease or to the efficiency of the surveillance system. As an alternative, we present spatial and non-spatial zero-inflated Poisson (ZIP) regressions for modelling the number of highly pathogenic avian influenza (HPAI) H5N1 outbreaks that were reported at subdistrict level in Thailand during the second epidemic wave (July 3rd 2004 to May 5th 2005). The spatial ZIP model fitted the data more effectively than its non-spatial version. This model clarified the role of the different variables: for example, results suggested that human population density was not associated with the disease occurrence but was rather associated with the number of reported outbreaks given disease occurrence. In addition, these models allowed estimating that 902 (95% CI 881–922) subdistricts suffered at least one HPAI H5N1 outbreak in Thailand although only 779 were reported to veterinary authorities, leading to a general surveillance sensitivity of 86.4% (95% CI 84.5–88.4). Finally, the outputs of the spatial ZIP model revealed the spatial distribution of the probability that a subdistrict could have been a false negative. The methodology presented here can easily be adapted to other animal health contexts.     

Genomic analysis of influenza A virus from captive wild boars in Brazil reveals a human-like H1N2 influenza virus

Influenza is a viral disease that affects human and several animal species. In Brazil, H1N1, H3N2 and 2009 pandemic H1N1 A(H1N1)pdm09 influenza A viruses (IAV) circulate in domestic swine herds. Wild boars are also susceptible to IAV infection but in Brazil until this moment there are no reports of IAV infection in wild boars or in captive wild boars populations. Herein the occurrence of IAV in captive wild boars with the presence of lung consolidation lesions during slaughter was investigated. Lung samples were screened by RT-PCR for IAV detection. IAV positive samples were further analyzed by quantitative real-time PCR (qRRT-PCR), virus isolation, genomic sequencing, histopathology and immunohistochemistry (IHC). Eleven out of 60 lungs (18.3%) were positive for IAV by RT-PCR and seven out of the eleven were also positive for A(H1N1)pdm09 by qRRT-PCR. Chronic diffuse bronchopneumonia was observed in all samples and IHC analysis was negative for influenza A antigen. Full genes segments of H1N2 IAV were sequenced using Illumina's genome analyzer platform (MiSeq). The genomic analysis revealed that the HA and NA genes clustered with IAVs of the human lineage and the six internal genes were derived from the H1N1pdm09 IAV. This is the first report of a reassortant human-like H1N2 influenza virus infection in captive wild boars in Brazil and indicates the need to monitor IAV evolution in Suidae populations.     

Serum ferritin and paraoxonase-1 in canine leishmaniosis

Ferritin and paraoxonase-1 (PON-1) were measured in dogs experimentally infected by Leishmania infantum (during experimental infection and following treatment) and also in naturally-infected dogs which presented different degrees of proteinuria. Experimentally-infected dogs were monitored for 7 months post-infection, then treated for 3 months with allopurinol, and their response to therapy was followed for 11 additional months. Naturally-infected dogs were staged based on the urine protein/creatinine (UPC) ratio into three groups as follows: group 1 (non-proteinuric; UPC ratio: <0.2), group 2 (borderline proteinuric; UPC ratio: 0.2–0.5) and group 3 (proteinuric; UPC ratio >0.5). An increase in serum ferritin values and a decrease in PON-1 activity were observed 2 months after infection. Both analytes returned to preinfection values following treatment. Significantly higher concentrations of ferritin were observed in dogs classified as either borderline or proteinuric when compared with non-proteinuric dogs whereas serum PON-1 activity was decreased only in proteinuric dogs.     

Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt

Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n = 1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010–2012. Cloacal and tracheal swabs and serum samples from domestic (n = 1242) and wild birds (n = 807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n = 306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n = 51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F = 15.7, p < 0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F = 29.5, p < 0.0001).     

A comparative study of pigeons and chickens experimentally infected with PPMV-1 to determine antigenic relationships between PPMV-1 and NDV strains

To compare the pathogenicity of PPMV-1 in pigeons and chickens, both species of birds were experimentally infected with strain pi/CH/LHLJ/110822, which was isolated from a pigeon in China. The clinical signs, gross lesions, and histopathological changes were observed in pigeons inoculated with pi/CH/LHLJ/110822. The morbidity and mortality rates were 80% and 70% in pigeons, respectively, whereas there were no clinical signs or gross lesions in chickens inoculated with the same strain. The viral loads in tissue samples were detected by real-time RT-PCR, indicating that six tissue samples (i.e., kidney, lung, brain, trachea, Harderian glands, and proventriculus) had detectable viral RNA in all dead pigeons, and significant differences in viral loads between pigeons and chickens were observed in several tissue samples (i.e., Harderian glands, proventriculus, duodenum, pancreas, small intestine, and large intestine) on 3 days post-inoculation (dpi) and in brain tissue on 7 dpi. In general, viral loads in pigeons were higher than those in chickens, whereas antibody titers in pigeons were lower than those in chickens. These results showed differences in pathogenicity, efficiency of viral RNA replication, and humoral immunity, indicating different susceptibilities between the host species. Additionally, the cross hemagglutination inhibition assay and cross virus neutralization tests demonstrated that pi/CH/LHLJ/110822 antigenicity was different from those of strains La Sota and F48E9.     

桑1-脱氧野尻霉素降血糖作用的研究进展

1-脱氧野尻霉素是桑树中的一种生物碱,是哺乳动物α-葡萄糖苷酶的有效抑制剂,具有降糖、降脂、抗病毒、抗肿瘤等药理作用。本文针对已报道的1-脱氧野尻霉素功能,综述了近年来1-脱氧野尻霉素降糖作用研究的最新进展,为更好利用和开发桑叶1-脱氧野尻霉素提供参考。