Detección de Chlamydia abortus en pérdidas reproductivas de bovinos en la provincia de La Pampa, Argentina / Detection of Chlamydia abortus in bovine reproductive losses in the province of La Pampa, Argentina

Las pérdidas reproductivas constituyen una causa importante de pérdida económica en el ganado bovino, aunque en más del 50% de los casos la etiología es desconocida. Las especies de la familia Chlamydiaceae han sido asociadas con abortos en bovinos y otras espeChlamydia abortus; cies animales, pero no existen datos al respecto en la República Argentina. El objetivo de este trabajo fue determinar la presencia de Chlamydia spp. y de Chlamydia abortus en pérdidas reproductivas de ganado bovino en La Pampa, Argentina. Se estudiaron 251 muestras provenientes de abortos y mortinatos. Se realizó PCR en tiempo real para la detección de la familia Chlamydiaceae y ArrayTube para la identificación de las especies presentes. Se detectó ADN de la familia Chlamydiaceae en 12 muestras (4,78%); el 83,33% (10/12) correspondió a abortos y el 16,66% (2/12) a mortinatos. El análisis por ArrayTube detectó C. abortus en 5 muestras (1,99% del total, 41,67% de las muestras con detección de Chlamydiaceae). Este trabajo presenta la primera confirmación de la presencia de ADN de diversas especies de Chlamydiaceae (incluida C. abortus) en muestras de pérdidas reproductivas de ganado bovino en Argentina. El valor de prevalencia hallado (4,78%) debe ser tomado como un valor basal, debido al tipo de muestras estudiadas. Se halló material genético de Chlamydiaceae que no coincidió con ninguna de las especies conocidas; esto podría deberse a variantes intraespecie o a especies autóctonas aún no descriptas. Es necesario avanzar en el estudio de la infección por estas bacterias en el ganado bovino de Argentina para conocer su dimensión y analizar su impacto económico y zoonótico, y también para planear medidas de prevención y control.

Reproductive losses linked to an infectious etiology in bovine cattle are a major economic concern worldwide. In Argentina, more than 50% of abortion cases have unknown causes. Species belonging to Chlamydiaceae family are frequent etiologic agents of abortion around the world; however, there is yet no information on their prevalence in Argentina. The objective of this work was to identify Chlamydia spp., and particularly C. abortus in reproductive losses from bovine cattle in La Pampa, Argentina. Real time PCR targeting Chlamydiaceae-specific DNA fragments was performed on 251 samples obtained from bovine abortions and stillborns, and ArrayTube was used for species identification on positive samples. Chlamydiaceae DNA was detected in 12 samples of aborted fetuses (4.78%), 83.33% (10/12) accounting for abortions and 16.66% (2/12) for stillborns. C. abortus was detected by ArrayTube in 5 cases (1.99% of all samples, and 41.67% of Chlamydiaceae positive samples). This study shows the first detection of Chlamydiaceae and C. abortus DNA on reproductive losses of bovine cattle in Argentina, and the described prevalence value (4.78%) should be taken as baseline value due to the type of samples analyzed. Detection of genetic material from Chlamydiaceae not matching any of the studied species could be due to intraspecies variants or local species not yet described. Further research on Chlamydia infections in bovine cattle in Argentina is imperative to describe their range, to analyze their economic and zoonotic implications and to make recommendations about prevention and control measures.

The Clinical Value of Chlamydia Phage Vp2 Protein / 天津医药

Objective To evaluate the effect of chlamydiaphage virus protein 2(Vp2) on the recombinant virus and virus screening research, and it clinical value thereof. Methods To compare the Vp2 protein sequences to get the conserva-tive region with COBALT. A phylogenetic tree was built with ProteinBlast of Distance tree. The amino acid sequence in the high conservative region was predicted by the methods of Gamier-Robson and Chou-Fasman, and its flexibe regions were predicted by Karplus method. The hydrophilicity plot was predicted by Kyte-Doolittle and Hopp-Woods method. The sur-face probability was analysed by Emini, and the antigenic index was analysed by Jameson-Wolf method. Results The six Chlamydiaphage Vp2 proteins were the highly conserved sequences. There were obvious differences between Chp1Vp2 and other 5 Vp2 proteins. There were the main structure-alpha helix and some cell epitopes in the high conserved region. Con-clusion Vp2 protein is the important component of chlamydia phage capsid with the conservative nature. Vp2 protein has complicated structures and high conservative region with strong immunogenicity, playing a practical value of research in vi-rus recombinantment and screening the wild strains of chlaymdia trachomatis phage.

Prevalência e fatores de risco associados à infecção por Chlamydophila abortus em granjas suinícolas tecnificadas no estado de Alagoas, Brasil / Prevalence and risk factors associated with infection by Chlamydophila abortus in commercial pig farms in the state of Alagoas, Brazil

Objetivou-se com este estudo calcular a prevalência e identificar os fatores de risco associados à infecção por Chlamydophila abortus em suínos criados em granjas tecnificadas no Estado de Alagoas, Brasil. Para compor a amostra do estudo foram utilizados 342 suínos, sendo 312 matrizes e 30 varrões oriundos de sete granjas de ciclo completo e distribuídas em cinco municípios do Estado de Alagoas. O diagnóstico sorológico da infecção por C. abortus foi realizado através da microtécnica de Fixação do Complemento (RFC). A análise dos fatores de risco foi realizada por meio da aplicação de questionários investigativos, constituídos por perguntas objetivas referentes ao criador, às características gerais da propriedade, ao manejo produtivo, reprodutivo e sanitário. Observou-se prevalência de 10,5% (36/342) de suínos soropositivos para a infecção por C. abortus, com 85,8% das granjas analisadas com animais positivos. As variáveis que demonstraram associação significativa foram: utilização de bebedouros comuns para jovens e adultos (p=0,024;OR=10,83; IC=1,36–86,03) e método de cobertura de monta natural associada à inseminação artificial (p=0,05; OR=7,62; IC=1,00-58,31). Relata-se a primeira ocorrência de anticorpos anti-C. abortus em suínos no Brasil. Fatores como a introdução de reprodutores nos plantéis e a forma de fornecimento de água foram evidenciados como facilitadores da infecção das matrizes neste estudo. Dessa forma, medidas de controle da infecção devem ser enfocadas nesse aspecto para evitar a disseminação do agente nas granjas suinícolas e em outros plantéis da região.

The objective of this study was to determine the prevalence and identify risk factors associated with Chlamydophila abortus infection in commercial swine farms on the state of Alagoas, Brazil. To compose the study sample 342 pigs were used, with 312 sows and 30 boars from seven swine farms and distributed in five districts of the Alagoas. The serological diagnosis of infection by C. abortus was performed by fixation of complement microtechnique (RFC). The analysis of risk factors were performed by the application of research questionnaires, consisting of objective questions relating to the designer, the general characteristics of the property, the production, reproductive and health management. I was observed a prevalence of 10.5% (36/342) of pigs seropositive for infection by C. abortus with 85.8% of farms with positive animals analyzed. The variables that showed significant association were use of common drinker for young and adults pigs (p=0.024, OR=10.83, CI=1.36-86.03) and associated the natural mount with artificial insemination (p=0.05, OR=7.62, CI=1.00-58.31). This work reports the first occurrence of anti-C. abortusin pigs in Brazil. Factors as the introduction of boars in herds and the form of water supply were seen as facilitators of infection on sows in this study. Thus measures of infection control should be focused on this aspect to prevent the spread of the agent in pig farms and other herds in the region.

Study on the perinatal Chlamydia Trachomatis infection in Chongqing area using urine Gap-LCR-ELISA / 中华围产医学杂志

Objective To study the prevalence of perinatal chlamydia trachomatis infection in the city of Chongqing. Methods First void urine (FVU) samples and cervical smear from 512 pregnant women (gestational age≥28 weeks) were collected. According to the “expanded gold standard”, the methodologic indices were compared between Gap LCR ELISA using plasmid probes and omp1 probes on FVU and cervical smear, respectively. Results (1) CT infection in pregnancy is usually asymptomatic. Forty two CT positive cases were confirmed by “expanded gold standard” indicating a prevalence of CT infection in pregnant women in Chongqing was 8.20%(42/512). Among these 42 women, 37 (88.1%) were detected from both FVU and cervical smear, while positive results were shown in 4 cases (9.5%) from cervical smear and only one case (1/42) 2.4% from FVU . (2) The sensitivity of Gap LCR ELISA using plasmid probes and ompl probes were 90.48% and 71.43% ( P 0.05). The specificity of all Gap LCR ELISA tests were 100%. Conclusions FVU plasmid Gap LCR ELISA is a noninvasive, highly sensitive and specific method which is suitable for large scale screening for perinatal CT infections in pregnant women in developing countries and regions.