New molecular marker for Trypanosoma (Duttonella) vivax identification

Trypanosoma vivax is a widespread hemoparasite in tropical areas and is pathogenic to ruminant domestic livestock as well as wild ruminants. The accurate identification of parasites in both hosts and vectors is crucial for epidemiological studies and disease control programs. We describe here the development of molecular markers specific for T. vivax identification. These markers were used to identify mouthpart infections in field-collected tsetse flies from Cameroon. The markers target the genomic sequence of a species-specific antigen from the bloodstream stages. No cross amplification with other trypanosome species was observed, which makes the markers a reliable tool to detect T. vivax infections, both in hosts and vectors. The PCR-amplified sequence contains a (CA)_n microsatellite repeat for which 11 different alleles were identified. This microsatellite, which showed high polymorphism, provides a suitable marker for population genetic studies.     

New data on the morphology of Procamallanus (Procamallanus) annulatus and Procamallanus (Spirocamallanus) monotaxis (Nematoda: Camallanidae) from marine fishes off New Caledonia

Two little-known nematode species of the family Camallanidae, intestinal parasites of marine perciform fishes, are reported from off New Caledonia: Procamallanus (Procamallanus) annulatus Yamaguti, 1955 from the goldenlined spinefoot Siganus lineatus (Valenciennes) (Siganidae) and Procamallanus (Spirocamallanus) monotaxis (Olsen, 1952) from the longspine emperor Lethrinus genivittatus Valenciennes and the slender emperor Lethrinus variegatus Valenciennes (both Lethrinidae). Detailed light and electron microscopical studies (the latter used for the first time in these species) revealed some taxonomically important, previously not observed features, such as the presence of deirids, six crescent-shaped elevations surrounding the mouth, three poorly developed protuberances on the female tail tip and circumcloacal papillae and phasmids on the male tail in P. annulatus, and the presence of a circumoral flange, only 12 (instead of 14 reported) cephalic papillae, the shape of deirids and similar numbers (14–17 and 14–15) of spiral ridges in the male and female buccal capsules in P. monotaxis. The fourth-stage larva of P. annulatus is described for the first time. Firststage larvae of both species were found to possess several digital processes at the tail tip. The present findings represent new host and geographical records of these parasite species.     

Pathogenicity of encapsulated Bacteroides melaninogenicus group, B. oralis and B. ruminicola subsp. brevis in abscesses in mice

The pathogenicity of 27 clinical isolates of the Bacteroides melaninogenicus (BM) group and four clinical isolates of B. oralis and B. ruminicola subsp. brevis were investigated by inoculating them into mice and subsequently determining their ability to cause subcutaneous (SC) or intraperitoneal abscesses. Only ii isolates of BM group and one B. ruminicola induced abscesses in mice, and all were found to be heavily encapsulated on recovery from the abscesses (more than 50 per cent of the organisms were encapsulated). When the other 23 isolates, however, were injected SC in combination with either Klebsiella pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus or Streptococcus pyogenes, abscesses were formed in 16 of the 23 combinations. The Bacteroides spp. recovered from the mixed infection were heavily encapsulated. Capsules also formed in Bacteroides if the organisms were injected together with capsular material or formalin killed cells of K. pneumoniae or encapsulated Bacteroides sp. Once non-encapsulated or only slightly encapsulated strains acquired a capsule, they could induce abscesses on reinoculation into mice.     

Life span alteration after irradiation in Drosophila melanogaster strains with mutations of Hsf and Hsps

The life span alteration after γ-irradiation and/or paraquat treatment in Drosophila in wild type strain Canton-S and strains with mutations of heat shock factor (1–4 alleles) and heat shock proteins (Hsp70Ba ³⁰⁴ , Hsp83 ^e6A , Hsp22 ^EY09909 , Hsp67Bb ^EY099099 ) was investigated. Chronic low-dose rate γ-irradiation (0.017 and 0.17 cGy/h) on pre-imago stages was used as a priming dose (absorbed doses were 4 and 40 cGy). Paraquat, a free radical inducing agent, was a challenging factor (20 mM for 1 day). It was shown that chronic irradiation led to adaptive response in both sexes except homozygous males and females with mutations of Hsf ⁴ and Hsp70Ba ³⁰⁴ . The gender-specific differences in stress response were discovered in wild type strain Canton-S, Hsp22 ^EY09909 Hsp67Bb ^EY09909 homozygotes and Hsp83 ^e6A heterozygotes: the adaptive response persisted in males, but not in females. Thus, Drosophila Hsp and Hsf mutation homozygotes did not demonstrate the adaptive response in the majority of cases, implying an important role of those genes in radiation hormesis and adaptation to stresses.     

Usefulness of cilostazol versus ticlopidine in coronary artery stenting

A combination of ticlopidine and aspirin has been accepted as the standard antithrombotic regimen after coronary stenting. However, ticlopidine poses serious side effects such as neutropenia or thrombocytopenia. Cilostazol, a cyclic adenosine monophosphate phosphodiesterase inhibitor, is a novel antiplatelet agent with vasodilatory properties. We compared the efficacy and safety of cilostazol plus aspirin (C+A) with ticlopidine plus aspirin (T+A) in elective coronary stenting. Three hundred patients were randomly assigned to receive C+A or T+A 2 days before stenting. The primary end point was a composite of angiographic stent thrombosis, or major cardiac events (death, myocardial infarction, bypass surgery, repeat intervention) at 30 days. The secondary end points were bleeding vascular complications, neutropenia, thrombocytopenia, or side effects requiring discontinuation of the drugs at 30 days. The primary end point was reached in 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of bleeding vascular complications was 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of drug-related side effects was not statistically different between the 2 groups but slightly higher in the T+A group than in the C+A group (2.7% vs 0.7%, p = 0.37). However, neutropenia was seen in 2 patients only in the T+A group. As a poststenting antithrombotic, C+A is as effective as T+A in preventing major cardiac events including stent thrombosis, and safer in that it does not cause neutropenia despite the fact that there is no statistical difference in the incidence of adverse effects and complications.     

Overexpression of c-Ki-ras and c-fos in human pancreatic carcinomas

The mRNA expression of protooncogenesc-Ki-ras, c-myc, andc-fos was studied in five pancreatic carcinomas and five normal pancreatic tissues using RNase protection assay and Northern blot analysis. The expression of those protooncogenes was detected in total mRNA from all specimens. However, the amounts in carcinomas and in normal tissues differed.C-Ki-ras mRNA in all the tumors was expressed up to sixfold more than in normal tissues.C-fos mRNA was also overexpressed up to tenfold in four of five tumors. In contrast,c-myc mRNA levels were varied and did not differ significantly between tumors and normal tissues. The results suggest that the overexpression ofc-Ki-ras andc-fos mRNA are implicated in the development of pancreatic adenocarcinoma.     

Mosaic mapping of foci associated with longevity in the neurological mutants Hk and Sh of Drosophila melanogaster

The shaker mutants Hk¹ and Sh⁵affect the nervous system and reduce lifespan, perhaps through activity-related metabolic rate. Three hundred y w Hk¹, y w Sh⁵, and y w mosaics were generated by an unstable ring-X, scored for external male and female tissues, and kept singly to determine the lifespan of each. Because the mosaics did not resolve themselves into distinct long- and short-lived categories, a computer curve-fitting method was developed to transform and combine the appropriate non-mosaic male (short-lived) and female control curves of percent dying per day, into an approximation of the curves observed for mosaics with a given cuticular landmark male on both, one, or neither side. The resulting estimates of long- and short-lived mosaics of each type were used to calculate the distance between each landmark and the developmental focus for Hk¹ and Sh⁵ life-shortening. In both cases the mutant focus was in the ventral anterior part of the thorax, perhaps in the anterior thoracic ganglion; the focus was submissive for Hk¹ and domineering for Sh⁵. At the same time,there was a second focus, independent of the mutant effect, associated with early mosaic death. In both shaker and control mosaics this early death focus mapped laterally in the region of the wing, and is probably the result of incompatible juxtapositions of male tissue in that region, and female tissue anteriorly. The curve-fitting method may be useful for analyzing other quantitative and multi-focus characters.     

齐氏姬鼠-大绒鼠鼠疫疫源地内鼠疫主要宿主动物和指示动物携带非鼠疫耶尔森菌的调查研究

目的 探讨齐氏姬鼠-大绒鼠鼠疫疫源地内鼠疫的主要宿主动物(鼠类)和指示动物(家犬)携带小肠结肠炎耶尔森菌的情况,掌握小肠结肠炎耶尔森菌在鼠疫自然疫源地内的生态学分布特征方法 采集的啮齿动物和犬类标本分离小肠结肠炎耶尔森菌,并进行血清分型、生物分型及毒力基因检测结果 从62份啮齿动物标本检出43株小肠结肠炎耶尔森菌,携带率35.5％;从171份犬类标本检出96株小肠结肠炎耶尔森菌,携带率26.3％;138株小肠结肠炎耶尔森菌为生物1A型;1株小肠结肠炎耶尔森菌为生物3型、血清O∶3型结论 啮齿动物较犬类小肠结肠炎耶尔森菌的携带率高。非致病性小肠结肠炎耶尔森菌菌株为优势菌型。在鼠疫疫源地内研究小肠结肠炎耶尔森菌的分布及生物学特征对该病的预防控制具有重要意义,也有助于探讨致病性耶尔森菌在自然界长期保存、变化的机理以及相互关系。     

鲍曼不动杆菌诱导Raw 264.7细胞自噬研究

目的 探讨鲍曼不动杆菌诱导鼠巨噬细胞Raw 264.7发生自噬的能力方法 鲍曼不动杆菌标准株(ATCC 17978)感染Raw 264.7细胞,于感染180 min时中止实验,收集细胞提取总RNA和总蛋白,通过Western boltting法检测自噬相关蛋白LC3和Beclin-1表达。同时通过qPCR法检测自噬相关基因atg3、atg4B、atg5、atg7、atg12、atg16L1、ULK1和GABARAPL1。结果 鲍曼不动杆菌感染Raw 264.7细胞后,细胞LC3和Beclin-1表达量较未感染组升高显著(F_(LC3)=457.2;F_(Beclin-1)=43.27,P＜0.01),自噬相关基因表达量atg3、atg4B、atg5、atg7、atg16L1、ULK1、GABARAPL1变化并不明显,而atg12表达量在180 min时升高显著(F=208.6,P＜0.01)结论 鲍曼不动杆菌可以诱导鼠巨噬细胞Raw 264.7发生自噬,其机制可能是通过ATG12- ATG7- ATG5信号传导通路,但其确切机制有待于进一步研究。     

Fulminant, Non-antibiotic Associated Clostridium difficile Colitis Following Salmonella Gastroenteritis

In the last decade there has been increasing awareness of the virulence and changing epidemiology of Clostridium difficile (C. difficile). While the vast majority of clinical cases of C. difficile are associated with antimicrobial or nosocomial exposure, this syndrome has been well described in the absence of antibiotic use. We present an unusual case of fatal, non-antibiotic associated C. difficile colitis following Salmonella serotype Saintpaul gastroenteritis in a previously healthy young person. We review the typical risk factors for C. difficile colitis and fulminant disease. We also review the epidemiology of community-acquired C. difficile-associated disease (CA-CDAD) and highlight Salmonella infection as a potential risk factor for development of CA-CDAD.     

Biotyping of Campylobacter jejuni and Campylobacter coli infections in Spain

Biochemical profiles were studied in 102 Campylobacter isolates from patients affected by enteric disease in Orense (Spain) over a 1-year period. The isolates were identified as hippurate-positive Campylobacter jejuni (n = 90), Campylobacter coli (n = 10) and hippurate-negative C. jejuni (n = 2). Seventy-seven of the hippurate-positive and both hippurate-negative C. jejuni isolates were biotyped as C. jejuni subsp. jejuni biotype 1, nine as C. jejuni subsp. jejuni biotype 2 and four as C. jejuni subsp. doylei. Hippurate-hydrolysis was correlated to a simple scheme based on L-arginine arylamidase production, propionate assimilation and malate assimilation which yielded sensitivity and specificity values of 0·90 and 1·00, respectively. Effective grouping of nalidixic acid-resistant C. jejuni and C. coli isolates (38·5% of the total) was also achieved.