Diet‐induced obesity increases the frequency of Pig‐a mutant erythrocytes in male C57BL/6J mice

Obesity increases the risk of a number of chronic diseases in humans including several cancers. Biological mechanisms responsible for such increased risks are not well understood at present. Increases in systemic inflammation and oxidative stress, endogenous production of mutagenic metabolites, altered signaling in proliferative pathways, and increased sensitivity to exogenous mutagens and carcinogens are some of the potential contributing factors. We hypothesize that obesity creates an endogenously mutagenic environment in addition to increasing the sensitivity to environmental mutagens. To test this hypothesis, we examined two in vivo genotoxicity endpoints. Pig‐a mutant frequencies and micronucleus frequencies were determined in blood cells in two independent experiments in 30‐week old male mice reared on either a high‐fat diet (60% calories from fat) that exhibit an obese phenotype or a normal‐fat diet (10% calories from fat) that do not exhibit an obese phenotype. Mice were assayed again at 52 weeks of age in one of the experiments. N‐ethyl‐N‐nitrosourea (ENU) was used as a positive mutation control in one experiment. ENU induced a robust Pig‐a mutant and micronucleus response in both phenotypes. Obese, otherwise untreated mice, did not differ from non‐obese mice with respect to Pig‐a mutant frequencies in reticulocytes or micronucleus frequencies. However, such mice, had significantly higher and sustained Pig‐a mutant frequencies (increased 2.5‐3.7‐fold, p < 0.02) in erythrocytes as compared to non‐obese mice (based on measurements collected at 30 weeks or 30 and 52 weeks of age). This suggests that obesity, in the absence of exposure to an exogenous mutagen, is itself mutagenic. Environ. Mol. Mutagen. 57:668–677, 2016. © 2016 Wiley Periodicals, Inc.     

肺泡表面活性物质治疗新生儿肺透明膜病的疗效观察

目的探讨肺泡表面活性物质治疗新生儿肺透明膜病的疗效。方法按照治疗方案不同将40例新生儿肺透明膜病患儿分为A组(注射用牛肺表面活性剂+辅助通气)20例和B组(猪肺磷脂注射液+辅助通气)20例,比较两组患儿预后情况、机械通气情况、住院情况、并发症情况以及治疗前后血气分析指标[氧分压(PaO_2)、二氧化碳分压(PaCO_2)、pH]变化情况。结果两组治疗总有效率均为95.00%,并无统计学差异(P0.05);两组患儿治疗后PaO_2、pH水平高于同组治疗前,PaCO_2、OI水平低于同组治疗前,差异显著(P0.05);两组患儿治疗后血气分析指标并无统计学差异(P0.05);两组患儿机械通气总时间、总吸氧时间、总住院时间并无统计学差异(P0.05);A组患儿总治疗费用低于B组,差异显著(P0.05);两组患儿并发症总发生率并无统计学差异(P0.05)。结论肺泡表面活性物质治疗新生儿肺透明膜病疗效确切,其中注射用牛肺表面活性剂药效优异且药物经济性良好。     

Lymphocyte subsets in bronchoalveolar lavage after exposure to Actinobacillus pleuropneumoniae in pigs previously immunized orally or by aerosol

Young pigs were immunized with the lung-pathogenic bacterium Actinobacillus (Haemophilus) pleuropneumoniae by aerosol or orally using viable and inactivated bacteria. The cellular changes in the bronchoalveolar lavage (BAL) were studied in repeated lavages after the pigs were infected with live bacteria. The nucleated cells in the BAL were differentiated and lymphocyte subsets determined. There were no major differences between the two routes of immunization or between viable and inactivated bacteria. The immunization induced an increase in all lymphocyte subsets studied and in the appearance of plasma cells and lymphoid blasts. The infection did not cause a further increase except in granulocytes. The lack of a booster-type increase in lymphocytes in the BAL might indicate a different immunologic reaction of the lung or that lymphocytes of the BAL do not represent lung lymphocytes in general. The protective effect of the immunization might be deduced from the increase in lymphocytes after immunization but not from the reaction pattern after infection. Offprint requests to: R. Pabst     

Assessment of a novel recombinant vesicular stomatitis virus with triple mutations in its matrix protein as a vaccine for pigs

Vesicular stomatitis virus (VSV) causes a serious vesicular disease responsible for economic losses in the livestock industry. Currently, there are no suitable vaccines to prevent VSV infection. Although the structural matrix (M) protein of VSV has been shown to be a virulence factor in rodent models, its role in the pathogenicity of VSV infection in livestock species is unknown. We hypothesized that VSV with mutations in the M protein represents a novel live attenuated vaccine candidate. To test this, we introduced mutations into VSV M protein using reverse genetics and assessed their attenuation both in vitro and in pigs, an important natural host of VSV. A recombinant VSV with a triple amino acid mutation in M protein (VSV_MT) demonstrated a significantly reduced ability to inhibit the type I interferon (IFN) signaling pathway and to shutoff host gene expression compared to WT-VSV and a mutant virus with a single amino acid deletion (VSV_ΔM51). Inoculation of pigs with VSV_MT induced no apparent vesicular lesions but stimulated virus-neutralizing antibodies and animals were protected against virulent VSV challenge infection. These data demonstrate that the M protein is an important virulence factor for VSV in swine and VSV_MT represents a novel vaccine candidate for VSV infections in pigs.     

Pigs immunized with Chinese highly pathogenic PRRS virus modified live vaccine are protected from challenge with North American PRRSV strain NADC-20

Modified live virus (MLV) vaccines developed to protect against PRRSV circulating in North America (NA) offer limited protection to highly pathogenic (HP) PRRSV strains that are emerging in Asia. MLV vaccines specific to HP-PRRSV strains commercially available in China provide protection to HP-PRRSV; however, the efficacy of these HP-PRRSV vaccines to current circulating NA PRRS viruses has not been reported. The aim of this study is to investigate whether pigs vaccinated with attenuated Chinese HP-PRRSV vaccine (JXA1-R) are protected from infection by NA PRRSV strain NADC-20. We found that pigs vaccinated with JXA1-R were protected from challenges with HV-PRRSV or NADC-20 as shown by fewer days of clinical fever, reduced lung pathology scores, and lower PRRS virus load in the blood. PRRSV-specific antibodies, as measured by IDEXX ELISA, appeared one week after vaccination and virus neutralizing antibodies were detected four weeks post vaccination. Pigs vaccinated with JXA1-R developed broadly neutralizing antibodies with high titers to NADC-20, JXA1-R, and HV-PRRSV. In addition, we also found that IFN-α and IFN-β occurred at higher levels in the lungs of pigs vaccinated with JXA1-R. Taken together, our studies provide the first evidence that JXA1-R can confer protection in pigs against the heterologous NA PRRSV strain NADC-20.     

猪股骨头支持带动脉入头分支的解剖学研究

目的　探索猪股骨头支持带动脉入头分支的数量、分布规律及外径大小并阐述其意义。 方法　解剖39例带有髋周血管的猪股骨头离体标本,分离支持带动脉,采用30%硫酸钡悬浮液显微灌注,观察支持带动脉入头分支的走形、数量、分布及外径。以时钟点位记录支持带动脉入头的分布规律,显微标尺测量支持带动脉入头分支的外径,并对各组支持带动脉入头最粗支的位置进行测量统计。 结果　猪股骨头共有（6.10±1.32）支动脉入头,主要分为后上、后下及前方3组,每组支持带动脉最粗支入头的时钟点位分别为（11：22~01：29）、（06：36~08：15）、（02：01~03：59）;直径分别为（0.37±0.11）、（0.52±0.11）、（0.35±0.09）mm。 结论　猪股骨头入头动脉的数量及位置相对恒定,入头动脉最粗支平均直径为（0.52±0.11）mm,来自后下组支持带动脉,为猪股骨头重要的血供来源。     

3D技术打印椎体在全脊椎整块切除术中应用的初步探索

目的初步探索3D技术打印椎体在全脊椎整块切除术(Total en bloc spondylectomy,TES)中应用的可行性。方法选取广东紫金蓝塘土猪3只,T12、L1椎体进行后路全椎体切除术,置入3D打印假体,于T11、L2进行双侧椎弓根螺钉固定。观察术后土猪活动度、脊柱影像、双后腿痛觉和肌力。术后4月时处死,观察实体标本情况。结果手术成功,术后猪双后腿活动、痛觉良好。正侧位X片及CT三维重建,实物脊柱3D打印椎体-脊柱复合体观察,提示假体位置、椎间高度、脊椎序列完好。结论 3D技术打印椎体在临床脊柱全椎体切除术中的应用具有可行性,但需充分做好术前准备,如抗感染、补充血容量、假体型号合适、手术器械齐全等,才能保证手术的顺利完成。     

Assessment of 5‐fluorouracil and 4‐nitroquinoline‐1‐oxide in vivo genotoxicity with Pig‐a mutation and micronucleus endpoints

Genotoxicity assessments were conducted on male Sprague Dawley rats treated with 5‐fluorouracil (5‐FU) and 4‐nitroquinoline‐1–oxide (4NQO) as part of an international validation trial of the Pig‐a mutant phenotype assay. Rats were orally exposed to 0, 11.5, 23, or 46 mg/kg/day 5‐FU for three consecutive days (Days 1–3); blood was sampled on Days ?1, 4, 15, 29, and 45. Pig‐a mutant phenotype reticulocyte (RET^CD59?) and mutant phenotype erythrocyte (RBC^CD59?) frequencies were determined on Days ?1, 15, 29, and 45, and percent micronucleated reticulocytes (%MN‐RET) were measured on Day 4. Rats were treated with 4NQO for 28 consecutive days by oral gavage, at doses of 1.5, 3, or 6 mg/kg/day. RBC^CD59? and RET^CD59? frequencies were determined on Days ?1, 15, and 29, and MN‐RET were quantified on Day 29. Whereas 5‐FU was found to increase %MN‐RET, no significant increases were observed for RBC^CD59? or RET^CD59? at any of the time points studied. The high dose of 4NQO (6 mg/kg/day) was observed to markedly increase RBC^CD59? and RET^CD59? frequencies, and this same dose level caused a weak but significantly elevated increase in MN‐RET (approximately twofold). Collectively, the results provide additional support for the combination of Pig‐a mutation and MN‐RET into acute and 28‐day repeat‐dose studies. Environ. Mol. Mutagen. 55:735–740, 2014. © 2014 Wiley Periodicals, Inc.     

Endovascular repair of the aortic arch in pigs by improved double-branched stent grafts

Introduction

This study aimed to evaluate the feasibility of total endovascular repair of the aortic arch in pigs using improved integrated double-branched stent grafts.

Methods

Improved self-expandable stent grafts with a main body and two integrated branches were prepared for the repair of the aortic arch in six pigs. The feasibility of using these stent grafts was evaluated with arteriography, computed tomography (CT), computed tomography angiography (CTA) and autopsy three months following the procedure.

Results

The double-branched stent grafts were placed successfully in the aortic arch in all six pigs. All pigs survived for at least three months and their biological behaviour was normal. Arteriography, CTA and animal necropsy revealed good fixation in all cases. Aortic valve function and coronary ostia remained intact, and CT of the head did not detect any lesion of cerebral infarction.

Conclusions

Endovascular repair of the aortic arch with an integrated double-branched stent graft is safe and feasible in animal studies.