Interspecific agonistic behaviour in small mammals in a Mexican high-elevational grassland

Field trials were conducted throughout an annual cycle to study the role of agonistic behaviour in explaining the relative abundance of the volcano mouse ( Neotomodon alstoni ) in a small mammal community in high-altitude grasslands of central Mexico. Intrasexual contests between N. alstoni and three other sympatric rodents ( Peromyscus melanotis, Microtus mexicanus, and Reithrodontomys megalotis ) were performed. Male and female P. melanotis (100 and 67% of contests, respectively) and M. mexicanus (82 and 100%) were aggressively dominant over N. alstoni , whereas R. megalotis (80 and 100%) were not aggressive. Agonistic behaviour in this species did not explain its greater abundance in the community.     

Diazepam metabolism by multiple forms of cytochrome P-450 in rat liver microsomes

The synthesis of pharmacologically active diazepam metabolites (oxazepam, 4-hydroxydiazepam, N-demethyldiazepam) in liver microsomes of intact and phenobarbital-, 3-methylcholanthrene- and dexamethasone-induced male and female Wistar rats as well as in a reconstituted system with isolated forms of cytochrome P-450 (P-450a, P-450b, P-450c, P-450d and P-450k according to the Ryan nomenclature) was studied. Marked sex-dependent differences in the rates of diazepam metabolism in liver microsomes of intact and induced animals were revealed. The changes in the spectrum of diazepam metabolites in liver microsomes of induced rats (as compared to control animals) were revealed. In a reconstituted system only phenobarbital-induced cytochromes P-450b and P-450k were found to be active participants of diazepam N-demethylation; none of the isoenzymes tested were shown to be involved in diazepam hydroxylation.     

Sequence variation in the outer-surface-protein genes of Borrelia burgdorferi

Borrelia burgdorferi is a spirochete pathogen transmitted among warm- blooded hosts by ixodid ticks. Frequency-dependent selection for variant outer-surface proteins might be expected to arise in this species, since rare variants are more likely to avoid immune surveillance in previously infected hosts. We sequenced the OspA and OspB genes of nine North American strains and compared them with nine strains previously described. For each gene, the mean number of synonymous substitutions per synonymous site and the mean number of nonsynonymous substitutions per nonsynonymous site show only a twofold excess of silent mutations. Synonymous rates vary widely along the OspB protein. Some regions show a significant excess of silent substitutions, while divergence in other regions is constrained by biased base composition or selection. The presence, in antigenically important regions of the protein, of significant variation among strains, as well as evidence for recombination among strains, should be considered in attempts to develop vaccines against this disease.      

Use of carminomycin on adult patients with acute leukemias]

The data on the clinical trials of karminomycin, a new antitumor antibiotic are presented. The drug was used in the treatment of 46 adult patients with leukemia. Karminomycin was used in primary inducing therapy and treatment of relapses. The results of the trials showed that karminomycin had a definite therapeutic activity in treatment of acute myeloblast leukemia at various stages of the process. A rapid effect of the antibiotic provided its use in emergency cases with rapidly progressing variants of the disease.     

青藏高原地区的光质对高原春小麦生长发育、光合速率和干物质含量影响的研究

本文模拟研究了高原地区的不同光质对春小麦的生长发育、光合速率和干物质含量等方面的影响。实验结果表明:(1)蓝光和蓝紫光的照射能使春小麦植株趋于矮壮。提高总叶绿素含量,增加叶绿素b值,并能延迟春小麦的生育期和干物质积累的时间。(2)红光和蓝紫光对春小麦品种的光合速率都比对照有提高效应,其中红光最显著,蓝紫光次之,而蓝光下最低。(3)红光和蓝紫光下积累的干物质含量均大于对照,蓝光下的较低。从而论证了青藏高原地区较好的光质,尤其丰富的蓝紫光是高原春小麦屡出高产的重要生态因素之一。为在这一地区充分利用这一得天独厚的有利条件挖掘更大的高产潜力提供了科学依据。     

Abnormal methylation of p16/CDKN2A AND p14/ARF genes GpG Islands in non-small cell lung cancer and in acute lymphoblastic leukemia

Multiplex methylation-sensitive PCR and methylation-specific PCR were employed in studying the methylation of CpG islands in the p16/CDKN2A and p14/ARF promoter and the first exon regions in non-small cell lung cancer (54 samples) and acute B-cell lymphoblastic leukemia (61 samples). Differences in methylation were detected between types of neoplasia as well as between CpG islands studied within the same types of tumors. High level of the p16/CDKN2A first exon CpC island methylation was revealed in non-small cell lung cancer (68%) and in acute B-cell lymphoblastic leukemia (55%) and the CpG island of p14/ARF first exon was nonmethylated in these types of tumors. The methylation of CpG-rich fragments of genes p16/CDKN2A and p14/ARF promoters was analysed. As was found out, CpG islands located in 5' areas of one and the same gene can differ in methylation frequencies. The comparison of sensitivity between methylation-specific PCR and methylation-sensitive PCR used in the methylations studies was carried out.     

利用假型反转录病毒对大部分胰腺切除后再生细胞的世系追踪

胰腺是一个重要的内外分泌混合腺, 胰腺发生损伤后能够再生。为了探讨胰腺活体细胞世系追踪的方法和胰腺损伤后再生细胞的来源,分别通过胰腺伤口涂抹并胰内注射、尾静脉注射及腹腔注射三种方法, 利用假型反转录病毒对成体小鼠大部分切除后胰腺的细胞进行世系追踪。结果发现在活体条件下, 与尾静脉注射及腹腔注射法相比, 胰腺伤口涂抹并胰腺内注射反转录病毒的方法能够更有效的标记胰腺细胞; 而且, 通过对标记细胞的世系追踪研究证明, 在胰腺损伤后, 胰腺腺泡细胞能够接受损伤信号刺激发生再生。为今后进一步利用反转录假病毒对活体胰腺进行细胞命运追踪研究奠定基础, 为利用反转录病毒载体进行胰腺疾病的基因治疗提供线索。     

应用GeneXpert MTB/RIF对肺外结核的快速检测及评估

目的 评估GeneXpert MTB/RIF检测肺外结核分枝杆菌的准确性,并与传统方法进行比较。 方法 选取2016年6月至2017年6月在本院就诊的144例疑似肺外结核病患者,对所有标本分别进行金胺“O”荧光染色镜检、液体培养及药敏试验、固体培养及比例法体外药敏试验和Xpert法检测。 结果 收集的144例疑似肺外结核标本中,确诊108例,以胸水、淋巴结活检和脓液感染较多,另36例阴性患者中,10例为非结核分枝杆菌感染。Xpert试验的敏感性为28.73%,特异性为96.00%,其阳性预测值和阴性预测值均高于其他3种检测方法。在阳性检出率方面,Xpert试验高于涂片镜检(χ2=17.39,P2=8.64,P2=2.56,P>0.05)。固体培养、液体培养和Xpert试验3种方法对结核分枝杆菌利福平耐药率检测差异无统计学意义(P>0.05),耐药率分别为8.33%、9.68%和11.11%,且Xpert试验方法检测出2株耐多药结核分枝杆菌,平均耗时2.5 h。 结论 GeneXpert MTB/RIF可以作为一种筛选及快速检测工具应用于肺外结核的诊断,同时可作为检测MDR TB的一种指标。