Quantitative real-time PCR and culture examination of Mycobacterium avium subsp. paratuberculosis at farm level

Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease in ruminants and may contribute to Crohn's disease in humans. The aim of this study was to determine the occurrence and quantity of MAP in cattle feces and milk in the Iranian context. In addition, we evaluated the effect of cattle age as well as farming system as risk factors contributing to MAP load. For this, a total sample of 373 consisting of 150 cattle feces (CF), 150 individual cow's milk (ICM), as well as 73 bulk-tank milk (BTM) was collected randomly and regardless of the cattle health status. The samples were assayed using F57 quantitative real-time PCR (qPCR) and culture method. According to the results of qPCR which was found ∼10 times more sensitive than culture assay, MAP was detected in 68.66% (103/150) of the CF, 12% (18/150) of the ICM and 52.05% (38/73) of the BTM samples. In contrast to the previous reports, the quantity of MAP in the BTM (2.03–5.97 log cfu/50 ml) was statistically (p < 0.01) higher than the ICM (0.90–1.97 log cfu/50 ml). Data suggested a direct relation (p < 0.01) between the cattle age and the quantity of MAP in the CF samples, while the relation was not statistically significant (p > 0.05) for the ICM. In addition, MAP load in the BTM samples obtained from traditional farms was significantly (p < 0.01) higher than that of the industrial ones, while the differences in CF and ICM was not significant (p > 0.05).     

Distribution of IS900 restriction fragment length polymorphism types among animal Mycobacterium avium subsp. paratuberculosis isolates from Argentina and Europe

Sixty-one Mycobacterium avium subsp. paratuberculosis isolates from cattle and deer from the Buenos Aires province, an important livestock region in Argentina, were typed by restriction fragment length polymorphisms (RFLP) analysis based on IS900. Four different RFLP patterns (designated ‘A’, ‘B’, ‘C’ and ‘E’) were identified in BstEII digests of genomic DNA. The most frequently observed type, pattern ‘A’, was found in 46 isolates (75%). The second, pattern ‘E’, included 8 isolates (13%), while the third, pattern ‘B’, included 6 isolates (10%). Pattern ‘C’ was found for only one isolate. All of the deer isolates were classified as pattern ‘A’, while cattle isolates represented all four RFLP patterns. Twenty-one isolates representing the four different BstEII-RFLP patterns were digested with PstI. Twenty isolates showed identical PstI-RFLP pattern. BstEII-RFLP patterns from Argentine cattle and deer were compared with patterns found in cattle, goat, deer, rabbit, and human isolates from Europe. The most common pattern in Argentina, pattern ‘A’, was identical to a less frequently occurring pattern R9 (C17) from Europe. The other Argentine patterns ‘B’, ‘C’ and ‘E’, were not found in the Europe. These results indicate that the distribution of M. avium subsp. paratuberculosis genotypes in the Buenos Aires province of Argentina is different from that found in Europe.     

朱砂叶螨为害前后抗、感木薯品种叶组织营养物质含量差异分析

为了明确营养物质在木薯抗螨性中的重要作用,在获得遗传稳定的抗、感螨参照标准木薯品种的基础上,采用分光光度法开展了朱砂叶螨为害前后抗、感螨参照标准木薯品种叶组织中营养物质含量的差异分析。结果表明：朱砂叶螨为害1、4、8 d的抗螨参照标准木薯品种C1115叶组织中的游离氨基酸（FAA）、可溶性糖（WSS）、可溶性氮（SN）含量均显著降低,分别是为害前的69.69%、69.29%和63.42%,73.16%、73.71%和72.75%,45.97%、46.21%和46.13%（P<0.05）;但糖氮比（S/N）显著升高,是为害前的159.15%、159.46%和157.83%（P<0.05）,游离脯氨酸（Pro）含量无显著变化。螨害1、4、8 d的感螨参照标准木薯品种BRA900叶组织中的FAA含量和WSS含量与为害前无显著差异,SN含量显著升高,是为害前的148.50%、148.73%和148.77%;S/N显著降低,是为害前的62.61%、61.48%和61.92%;Pro含量显著升高,是为害前的373.82%、367.33%和362.61%,但为害前后无显著性差异（P<0.05）。     

基于物联网的家用电灯开关无线控制系统设计

设计了一种基于物联网的家用电灯智能无线控制系统。系统设计了以Cortex-M3内核的stm32处理器作为系统主机控制器电路,采用STC89C52RC单片机的从机电路,实现开关控制功能和检测电流传感器的输出数据。系统以手机短信和NRF24L01实现射频通信,系统的用户端与控制端的信息传递通过GSM模块-SIM900A的短信接收与发送完成,从而实现了智能无线控制控制系统中的手机与家用电器的物物连接。     

HVI900仪测试棉纤维品质的误差及其控制

对ＨＶＩ９００仪测试棉纤维品质的误差及其控制进行了研究。结果表明，（１）ＨＶＩ９００仪本身存在测试误差；（２）各品种与标准棉样纤维品质的变异趋势基本一致，但前者的变异程度远大于后者；（３）纤维品质中，以比强度的变异系数最大，麦克隆值的变异系数最小；（４）中期花的纤维品质好于混合花，且变异程度小于混合花。为了使纤维品质的测定结果具有一定的精度，中期花和混合花的测试次数分别以１０次和２０次为宜     

Distribution of IS900 restriction fragment length polymorphism types among animal Mycobacterium avium subsp. paratuberculosis isolates from Argentina and Europe

Sixty-one Mycobacterium avium subsp. paratuberculosis isolates from cattle and deer from the Buenos Aires province, an important livestock region in Argentina, were typed by restriction fragment length polymorphisms (RFLP) analysis based on IS900. Four different RFLP patterns (designated ‘A’, ‘B’, ‘C’ and ‘E’) were identified in BstEII digests of genomic DNA. The most frequently observed type, pattern ‘A’, was found in 46 isolates (75%). The second, pattern ‘E’, included 8 isolates (13%), while the third, pattern ‘B’, included 6 isolates (10%). Pattern ‘C’ was found for only one isolate. All of the deer isolates were classified as pattern ‘A’, while cattle isolates represented all four RFLP patterns. Twenty-one isolates representing the four different BstEII-RFLP patterns were digested with PstI. Twenty isolates showed identical PstI-RFLP pattern. BstEII-RFLP patterns from Argentine cattle and deer were compared with patterns found in cattle, goat, deer, rabbit, and human isolates from Europe. The most common pattern in Argentina, pattern ‘A’, was identical to a less frequently occurring pattern R9 (C17) from Europe. The other Argentine patterns ‘B’, ‘C’ and ‘E’, were not found in the Europe. These results indicate that the distribution of M. avium subsp. paratuberculosis genotypes in the Buenos Aires province of Argentina is different from that found in Europe.     

Unique genotypes of Mycobacterium avium subsp. paratuberculosis strains of Type III

Mycobacterium avium subsp. paratuberculosis (MAP) strains with two new IS900 restriction fragment length polymorphism (RFLP) BstEII types intermediate suspected to belong to the MAP Type III group were isolated from migrating sheep in Germany. Such strains have only been sporadically identified in a few studies. For a better understanding of the genomic diversity of MAP with regard to specific host associations, geographic origin, and the discussed classification into Type I, Type II and Type III, these isolates were further characterized.Using IS900-RFLP, the isolates showed unique fingerprint patterns after BstEII-, PstI-, PvuII- and BamHI-digestion which had not been published before. Additionally, using gyrB-PCR-restriction endonuclease analysis (PCR/REA) and mycobacterial interspersed repetitive unit (MIRU)-PCR, the two strains showed differences to known patterns of the Type I as well as the Type II group. Unique genotypes were also obtained with multilocus short sequence repeat (MLSSR) sequencing and MIRU-variable-number tandem-repeat (VNTR) typing.As expected, genomic profiles identical to the Type I and different from the Type II group were detected by IS1311-PCR/REA, IS1311 sequencing as well as by Large Sequence Polymorphism analysis (LSP^A 8, 17, 20, 4-II, and 18).In addition to distinct growth characteristics, the unique genotypes of the studied sheep strains support their affiliation to the assumed third group within the MAP subspecies and suggest the existence of different genotypes within this Type III group. The results could serve as further evidence that Type I and Type III groups are more closely related to each other than to the bovine Type II group.     

基于HC900控制器的抗生素发酵过程控制系统

针对某厂抗生素发酵过程控制的实际状况,设计了基于HC900控制器和组态软件的抗生素发酵过程控制系统。该控制系统采用HC900系列控制器C70R及其I/O模块组成下位机,上位机采用工控机＋iFIX组态软件,对采集的数据进行集中管理和实时监控。分别设计了温度、补料、pH、罐压、溶解氧和消泡的控制方法。此系统提高了抗生素发酵过程控制系统的控制精度和可靠性。     

栽培密度对湘两优 900 产量及主要农艺性状的影响

【目的】湘两优 900 是国家杂交水稻工程技术研究中心（湖南）培育的超高产新品种,具有茎秆粗壮、 成穗率高、大粒大穗结实率高的超高产特征。该品种 2017 年早造在广东省惠州市惠阳区超高产栽培条件下进 行密度差异对产量及农艺性状的影响试验。【方法】试验采用裂区设计,设置 13 cm×13 cm 到 24 cm×24 cm 插植密度（主处理）和单、多株植处理（副区）,田间采样和室内考种获取数据,以 Microsoft Excel 进行数据 整理,用 DPS 数据处理系统进行裂区方差分析。【结果】在珠江三角洲区域丘陵水稻土超高产栽培条件下,湘 两优 900 在 19 cm×19 cm 插植密度下可获得最高产量及最高有效穗数、每穗总粒数、每穗实粒数、结实率和 总生物量。【结论】湘两优 900 有长生育期产量潜力,可以在一季中稻区发挥高产潜力。湘两优 900 茎秆粗壮 占用空间较多,对插植苗数不敏感,建议疏植。     

Molecular epidemiology of Mycobacterium avium subspecies paratuberculosis: IS900 PCR identification and IS1311 polymorphism analysis from ruminants in the Punjab region of India

Johne's disease is chronic granulomatous infectious enteritis of animals caused by Mycobacterium avium subspecies paratuberculosis. A total of 153 animals from 19 dairy farms, 2 gaushalas (unproductive-animal rehabilitation centers), 2 goat and 2 sheep farms from different districts of the Punjab region were selected on the basis of clinical signs of disease. All samples from cattle (n = 86), buffalo (n = 34), goat (n = 25) and sheep (n = 26) were subjected to Ziehl-Neelsen staining and DNA extraction by a freeze and thaw method. Ziehl-Neelsen staining detected 71% samples positive for acid-fast bacilli whereas IS900 PCR detected 55% positive for Map DNA. IS1311 PCR-REA analysis of IS900 positive samples revealed ‘Bison’ type as the most prevalent (82%) genotype of Map, infecting all domestic ruminants. ‘Cattle’ type was present in a minority of cases (15%) from cattle, buffaloes and goats. This is the first report of ‘Cattle’ type Map from buffalo and goat species in India.