Mycoplasma gallisepticum experimental infection and tissue distribution in chickens,sparrows and pigeons

The most effective approaches to control the spread of Mycoplasma gallisepticum include strict biosecurity measures, continuous surveillance and eradication of infected flocks. The rapid expansion of the poultry industry worldwide in restricted geographical areas and severe economic losses due to M. gallisepticum outbreaks make it crucial to identify and better control the vectors responsible for the transmission of the disease. In the present study we evaluated the susceptibility of sparrows and pigeons to M. gallisepticum and the tissue distribution of M. gallisepticum in these species as compared with chickens. This information will further define the role of these common avian species in M. gallisepticum transmission. Twenty-six chickens, pigeons, and sparrows were experimentally inoculated with a field strain of M. gallisepticum and were monitored for the development of clinical signs, seroconversion, productive infection by culture, and M. gallisepticum distribution in their tissues by immunohistochemistry. All M. gallisepticum-inoculated chickens showed mild respiratory signs, seroconverted (haemagglutination inhibition geometric mean titre = 494) and shed M. gallisepticum in their tracheas. M. gallisepticum antigens were observed at high levels by immunohistochemistry in their tracheas, conjunctivas, nasal turbinates, and air sacs. The pigeons and sparrows did not show clinical signs or seroconvert but M. gallisepticum was reisolated up to 7 days post inoculation from pigeons and intermittently from sparrows. M. gallisepticum antigens were observed at low level in the conjunctiva of some pigeons and sparrows, as well as in the trachea of some sparrows. We conclude that pigeons and sparrows are partially susceptible to M. gallisepticum infection but do not seroconvert or maintain a steady carrier state similar to chickens and that these species may play a role in M. gallisepticum transmission between poultry farms as mechanical vectors.     

普萘洛尔或血管紧张素Ⅱ结合胃癌单克隆抗体与丝裂霉素交联物导向治疗的实验研究

观察了普萘洛尔和血管紧张素Ⅱ(AT-Ⅱ)对胃癌单克隆抗体3H11和丝裂霉素(MMC)交联物导向治疗的增强作用。在荷瘤裸鼠体内观察,交联物的抑瘤率达50％,联合应用普萘洛尔或AT-Ⅱ,可使抑瘤率分别提高到79％和60％。从~(131)Ⅰ-3H11,在荷瘤裸鼠体内的生物学分布实验中也看到,普萘洛尔或AT-Ⅱ均能提高肿瘤组织对~(131)Ⅰ-3H11的摄取量。此结果表明,血管活性物质确可通过改善肿瘤血管的血流灌注,增加肿瘤内交联物含量,增强导向治疗的疗效。     

中国118家实验室精液分析状况的调查

为在实验室内和实验室间实现精液分析标准化和进行质量控制,必须了解目前男科实验室精液分析的状况。为此,对中国大陆地区的部分精液分析实验室进行了调查。设计的"男科实验室精液分析调查表",包含36个问题,涉及精液分析的相关内容。本研究发放调查表145份,回收有效调查表118份。调查显示,53.6%(59/110)的实验室采用目测法检测精液量;对液化不全精液,70.9%(73/103)的实验室未作任何处理;精子密度、活动率、存活率及形态学分析以手工普通光学显微镜分析和计算机辅助精液分析(CASA)系统检测并存;精子染色方法达5种以上;精子自身抗体检测以酶联免疫吸附试验(ELISA)为主;仅有27.1%(32/118)的实验室开展了精浆生化项目检测。而且,在参与调查的所有实验室中,无一家实验室开展精液分析的室内和室间质量控制。总之,在中国大陆,男科实验室精液分析的方法和报告方式很不统一。采用的精液分析方法与《世界卫生组织人类精液分析实验室手册》第4版推荐的方法也不一致。本研究提示,为使不同实验室的检测结果具有可比性且有意义,中国男科实验室目前使用的精液分析方法急需标准化和质量控制。     

Human and animal brucellosis in Jordan between 1996 and 1998: a study

Between 1996 and 1998, a total of 2,494 samples of blood from humans and animals were collected and tested for brucellosis. This total included 1,594 samples of animal blood, collected from 1,050 sheep from 20 flocks, and 544 goats from eight herds. The serum samples were tested using the Rose Bengal test, the tube agglutination test, the complement fixation test and an enzyme-linked immunosorbent assay. Moreover, a complete history was compiled from each flock/herd. The rate of abortions in sheep due to brucellosis ranged from 0.5% to 56%, with a mean of 33.2%. The goats had a higher abortion rate. Thirty-four aborted sheep foetuses collected from these 20 flocks were bacteriologically and pathologically examined. A pure culture of Brucella melitensis biotype 3 was isolated from 21 of the aborted foetuses. The human blood samples were collected from two groups: first, from 800 apparently healthy people who were reporting to community hospitals for routine health checks and secondly, from 100 people from groups with a high-risk of contracting brucellosis, such as veterinarians, sheep-herders and laboratory technicians. The Brucella antibody titres for the 900 human serum samples were obtained using the microtitre agglutination test. The cumulative percentage of the serum samples showing a titre reading greater than 1:80 was higher in the at-risk group than among the normal population (7% compared to 4.1%). Although these results were not statistically significant, the higher percentage of positive reactors among the high-risk group may indicate an increased risk factor among professional agricultural and veterinary personnel in Jordan. It was concluded that brucellosis is common in sheep and goats in Jordan, subjecting the human population to high risks. Brucella melitensis Rev. 1 vaccination has been internationally recognised as the key to successfully controlling the disease. All animals in Jordan were repeatedly vaccinated between 1996 and 1998 on a trial basis, using a reduced dose of 1 x 10(5) colony-forming units (CFU). Cumulative data on the annual rate of human cases of brucellosis indicate that fewer people are affected each year. The same is true for the rate of abortions in animals. Such evidence strongly suggests that the vaccination programme has been successful. However, as wild strains of Brucella have also been isolated from vaccinated animals, the authors recommend increasing the amount of vaccine to a full dose of 1 to 2 x 10(9) CFU and vaccinating young female animals between the ages of three and eight months. To avoid brucellosis in humans, people should be educated about the dangers of contact with infected animals and the consumption of raw milk and milk products.     

N-myc gene amplification in neuroblastoma is associated with altered phosphorylation of a proliferation related polypeptide (Op18)

We have recently identified and cloned the gene for a cytosolic polypeptide, designated oncoprotein 18 (Op18), which is expressed in acute lymphocytic leukemia and some solid tumors including neuroblastoma. Op18 is phosphorylated upon treatment of lymphoid cells with phorbol myristate acetate. We have proposed that unphosphorylated Op18 plays a role in cellular proliferation, and that its phosphorylated forms, namely Op18a and Op18b, are associated with diminished cell proliferation. In this study, we report that in neuroblastoma tumors, the phosphorylation of Op18 was substantially diminished with increasing N-myc gene copy number. Treatment of the neuroblastoma cell line SMS-KCNR, which contains 75 copies of the N-myc gene, with retinoic acid for ten days resulted in an increase in Op18 phosphorylation. Our findings provide evidence for distinct patterns of Op18 phosphorylation in neuroblastoma tumors with and without N-myc gene amplification.     

PCR-restriction endonuclease analysis of Mycobacterium avium subsp. paratuberculosis isolates from goats, sheep, and cattle in Jordan

Paratuberculosis is an endemic disease and induces high economical losses in Jordan. There is no information available on genotypic variation of Mycobacterium avium subsp. paratuberculosis (MAP) isolated from animals in Jordan. In this study, we investigated 150 fecal samples from sheep, goats, and cattle for the presence of paratuberculosis using bacterial culture and polymerase chain reaction (PCR)-RFLP analysis of insertion sequence IS1311. Analysis of the results revealed that genotypic information from sheep, goat, and cattle could classify them into cattle or sheep strains. All culture isolates from cattle, 12.5% of the isolates from sheep, and 50% of the isolates from goats were cattle strain, while 87.5% of the isolates from sheep and 50% of the isolates from goats were sheep strain. Sequencing of the IS1311 268?bp PCR product from the three animal species confirmed the different MAP patterns.