Detecção de Aeromonas spp. e do gene de virulência aerolisina em tilápias do Nilo (Oreochromis niloticus) com a técnica de mPCR / Detection of Aeromonas spp. and virulence gene aerolysin in Nile tilapia (Oreochromis niloticus) using PCR technique

As infecções causadas por bactérias do gênero Aeromonas estão entre as doenças mais comuns em peixes cultivados em todo o mundo, com ocorrência de aeromoniose em todos os países que possuem cultivo de tilápia do Nilo (Oreochromis niloticus). O presente trabalho descreve o desenvolvimento de uma nova multiplex PCR (mPCR) para diagnóstico de Aeromonas spp. e identificação do gene aerolisina (aerA). Para padronização da mPCR foram utilizadas cepas de referência de várias espécies do gênero Aeromonas e de outros gêneros. Também foram usadas cepas de campo de A. hydrophila oriundas de cultivos de peixes pacamãs (Lophiosilurus alexandri) e Aeromonas spp. de tilápias do Nilo. Os primers foram desenhados com base na região 16S rRNA e aerA. Para verificar a melhor temperatura de anelamento foram utilizados gradientes entre 59°C a 61°C com 40ng de DNA molde. Os produtos da amplificação da região 16S rRNA e do gene aerA apresentaram 786 e 550pb, respectivamente. A mPCR apresentou melhor temperatura de anelamento a 57,6°C com limite de detecção das concentrações de DNA em ambos genes (16S rRNA and aerA) de 10-10g/μL. A mPCR padronizada é rápida, sensível e específica no diagnóstico de Aeromonas spp. e identificação do gene aerolisina. Esta metodologia apresenta vantagens quando comparada aos métodos de diagnóstico convencionais, podendo ser utilizada em cultivos comerciais de tilápias do Nilo ou outros peixes. A identificação do gene aerolisina é uma importante ferramenta na determinação do potencial patogênico dos isolados de Aeromonas spp. estudados.(AU)

Infections caused by bacteria of the genus Aeromonas are among the most common diseases in fish farming systems worldwide, and this disease occurs in all countries which have Nile tilapia (Oreochromis niloticus) farmed. The present work describes the development of a new multiplex PCR (mPCR) technique that diagnosis the genus Aeromonas and detects aerolysin gene (aerA). Reference strains of several Aeromonas species and other genera were used for standardization of mPCR. Strains of A. hydrophila from "pacaman" fish (Lophiosilurus alexandri) and Aeromonas spp. from Nile tilapia from farming systems were used too. Primers were designed based on the 16S rRNA region and aerA (aerolysin toxin). To verify a better annealing temperature were used gradients between 59°C and 61°C with 40ng of the DNA template. The 16S rRNA gene and the aerA gene amplification products showed 786 and 550 bp, respectively. The mPCR showed better annealing temperature at 57.6°C, and the detection limit for both genes (16S rRNA and aerA) was 10-10g/μL of the DNA. The standardized mPCR is quick, sensitive, and specific for Aeromonas spp. diagnosis and to detect aerolysin gene. This method showed advantages when compared to the conventional diagnostic methods and can be used in Nile tilapia or other fish farming systems. The detection of aerolysin gene is an important tool to determine the potential pathogenicity of Aeromonas spp. isolates.(AU)

Padronização de multiplex PCR para detecção de dermatófitos em pelos e crostas de cães e gatos / Standardization of a PCR multiplex for the detection of dermatophytes in dogs and cats fur and crusts

Objetivou-se padronizar uma reação do tipo multiplex PCR (mPCR) para detectar Microsporum canis, Microsporum gypseum e o complexo Trichophyton mentagrophytes em amostras de pelos e/ou crostas de cães e gatos. 250 amostras de pelos e/ou crostas de cães e gatos foram analisadas por meio de exame direto e cultura, o DNA das mesmas foi extraído para mPCR. Primers foram desenhados e como controle positivo da reação utilizou-se o DNA extraído de colônias de M. canis (URM 6273), M. gypseum (URM 6921) e T. mentagrophytes (URM 6211), provenientes da Coleção de Culturas (Micoteca URM), Departamento de Micologia, Centro de Ciências Biológicas da Universidade Federal de Pernambuco (CCB/UFPE). Como controles negativos de reação, utilizou-se água destilada esterilizada e DNA extraído de Alternaria sp. para verificar a especificidade dos primers. Do total de amostras analisadas, 15 (6%) foram identificadas, em cultura, como dermatófitos, e destas, 10 foram M. canis, três M. gypseum e dois T. mentagrophytes (complexo). Destas 15 amostras positivas, 11 (73,3%) foram detectadas por meio da mPCR. Além destas, seis outras, negativas em cultura, foram identificadas como M. gypseum. Verificou-se uma boa concordância entre os resultados da cultura e mPCR (Kappa: 0,66). O protocolo padronizado neste estudo pode ser utilizado como um método de triagem, por apresentar uma sensibilidade maior que a da cultura, usado paralelamente aos exames de rotina, permitindo um diagnóstico em menor tempo.(AU)

The aim of this study was to standardize a multiplex PCR (mPCR) reaction to detect Microsporum canis, Microsporum gypseum and the Trichophyton mentagrophytes complex in dog and cat fur and/or crusts. 250 fur and/or crusts samples from dogs and cats were analyzed by direct examination and culture, DNA from them was extracted for mPCR. Primers were designed and the DNA extracted from colonies of M. canis (URM 6273), M. gypseum (URM 6921) and T. mentagrophytes (URM 6211) from the Collection of Cultures - URM Micoteca - Department of Mycology, Biological Sciences Center of the Federal University of Pernambuco (CCB / UFPE). As negative controls, sterile distilled water and DNA extracted from Alternaria sp., were used to verify the specificity of the primers. Of the total samples analyzed, 15 (6%) were identified in culture as dermatophytes, and of these, 10 were M. canis, three M. gypseum and two T. mentagrophytes (complex). Of these 15 positive samples, 11 (73.3%) were detected by mPCR. Besides these, six others, negative in culture, were identified as M. gypseum. There was good agreement between culture results and mPCR (Kappa: 0.66). The protocol standardized in this study can be used as a screening method, because it has a sensitivity greater than that of the culture, used in parallel to the routine exams, allowing a diagnosis in a shorter time.(AU)

Occurrence of Mycoplasma bovigenitalium and Ureaplasma diversum in dairy cattle from to Pernambuco state, Brazil / Ocorrência de Mycoplasma bovigenitalium e Ureaplasma diversum em bovinos leiteiros do estado de Pernambuco, Brasil

The objective of this study was to conduct an investigation of Mycoplasma bovigenitalium and Ureaplasma diversum infections in cattle in the microregion of the Ipanema Valley, state of Pernambuco, Brazil. Vaginal swabs were collected from 355 breeding cows in reproductive age and were analyzed by multiplex PCR (mPCR) and culture. An epidemiological investigation of risk factors was performed for Mollicutes. mPCR analysis showed that, 9.29% (33/355) of the cows were positive for M. bovigenitalium and 21.69% (77/355) for U. diversum; coinfection was observed in 2.81% (10/355) of the cows. The microbiological isolation showed, 81.81% (27/33) of Mycoplasma spp. and 24.67% (19/77) of Ureaplasma spp.. The risk factors related to Mollicutes infection identified were semi-intensive breeding system (OR= 4.6), pasture rent (OR= 3.6), non-isolation of animals with reproductive disorders (OR= 3.2), and natural mounting and artificial insemination (OR= 3.5). There was a significant association between Mollicutes infection and abortions in the first gestational third (P= 0.001). This is the first record of M. bovigenitalium and U. diversum infection in cows in the semiarid region of the state of Pernambuco, Brazil. Preventive measures directed to the identified risk factors can decrease the occurrence of Mollicutes in these herds.(AU)

O objetivo deste estudo foi realizar uma investigação de Mycoplasma bovigenitalium e Ureaplasma diversum em bovinos leiteiros da microrregião do Vale do Ipanema, estado de Pernambuco, Brasil. Foram coletados suabes vaginais de 355 vacas em idade reprodutiva. As amostras foram analisadas por multiplex PCR (mPCR) e cultura. Foi realizada uma investigação dos fatores de risco para Mollicutes. Na mPCR, 9,29% (33/355) das vacas foram positivas para M. bovigenitalium e 21,69% (77/355) para U. diversum; coinfecção foi observada em 2,81% (10/355) das vacas. O isolamento microbiológico mostrou crescimento de Mycoplasma spp. em 81,81% (27/33) das amostras e em 24,67% (19/77) para Ureaplasma spp. Os fatores de risco relacionados à infecção por Mollicutes identificados foram sistema de produção semi-intensivo (OR= 4,6), aluguel de pastagem (OR= 3,6), não isolamento de animais com desordens reprodutivas (OR= 3,2) e monta natural e inseminação artificial (OR= 3,5). Houve uma associação significativa entre a infecção por Mollicutes e abortos no primeiro terço gestacional (P=0,001). Este é o primeiro relato da infecção por M. bovigenitalium e U. diversum em vacas na região semiárida do estado de Pernambuco, Brasil. As medidas preventivas direcionadas aos fatores de risco identificados podem diminuir a ocorrência de Mollicutes nesses rebanhos.(AU)

Clinical Significance of Fecal Lactoferrin and Multiplex Polymerase Chain Reaction in Patients with Acute Diarrhea

BACKGROUND/AIMS: The diagnostic yield of fecal leukocyte and stool cultures is unsatisfactory in patients with acute diarrhea. This study was performed to evaluate the clinical significance of the fecal lactoferrin test and fecal multiplex polymerase chain reaction (PCR) in patients with acute diarrhea. METHODS: Clinical parameters and laboratory findings, including fecal leukocytes, fecal lactoferrin, stool cultures and stool multiplex PCR for bacteria and viruses, were evaluated prospectively for patients who were hospitalized due to acute diarrhea. RESULTS: A total of 54 patients were included (male, 23; median age, 42.5 years). Fecal leukocytes and fecal lactoferrin were positive in 33 (61.1%) and 14 (25.4%) patients, respectively. Among the 31 patients who were available for fecal pathogen evaluation, fecal multiplex PCR detected bacterial pathogens in 21 patients, whereas conventional stool cultures were positive in only one patient (67.7% vs 3.2%, p=0.000). Positive fecal lactoferrin was associated with presence of moderate to severe dehydration and detection of bacterial pathogens by multiplex PCR (21.4% vs 2.5%, p=0.049; 100% vs 56.5%, p=0.032, respectively). CONCLUSIONS: Fecal lactoferrin is a useful marker for more severe dehydration and bacterial etiology in patients with acute diarrhea. Fecal multiplex PCR can detect more causative organisms than conventional stool cultures in patients with acute diarrhea.

Utilization of the respiratory virus multiplex reverse transcription-polymerase chain reaction test for adult patients at a Korean tertiary care center

BACKGROUND/AIMS: Respiratory viruses (RVs) are considered to be important respiratory pathogens in adult patients, and the multiplex reverse transcription-polymerase chain reaction (RT-PCR) test is used frequently in adult patients with respiratory infections. However, clinical data regarding utilization of the multiplex RT-PCR test for RVs are lacking. METHODS: We investigated the utilization of the multiplex RT-PCR test for RVs at Chung-Ang University Hospital in Seoul, Korea, between January 2012 and April 2013. RESULTS: During the study period, the multiplex RT-PCR test was performed for 291 adult patients. The test frequency was 4.9% of rapid influenza antigen detection tests and 0.8% of respiratory bacterial culture studies. A turnaround time of < 48 hours was observed in 25.9% of positive tests. Most of the tests were performed for admitted patients (97.9%) with a community-acquired infection (84.2%) during the flu season (82.5%). RVs were detected in 81 of 291 cases (27.8%). The RV positivity rates for community- and hospital-acquired infections did not differ (28.6% vs. 23.9%, p = 0.52). Of 166 patients with pneumonia, 44 (26.5%) had a viral infection. Among the patients with RV-associated pneumonia, an RV other than influenza was detected in 20 patients (45.4%). CONCLUSIONS: The multiplex RT-PCR test for RVs was infrequently performed at a tertiary care center, and the test results were often reported late. The test was most often performed for admitted adult patients with community-acquired infections during the flu season. The utilization of multiplex RT-PCR testing for RVs in current clinical practice should be improved.

Detection of filarial parasites and Wolbachia endosymbiotic bacteria in mosquitoes by PCR

Wuchereria Bancroft; the principal etiologic agent of lymphatic filariasis is mosquito dependant in the biological transmission. Dirofilariasis is essentially a disease of canines which can also be trans-mitted to humans by culicine mosquitoes. Wolbachia are Rickettsia-like, obligatory intracellular bacteria that infect the reproductive and somatic tissues of some arthropods and nematodes. Our study aimed to identify the possible association between filarial parasites and Wolbachia by single and multiplex PCR. 1600 female mosquitoes collected from: four localities in Assiut Governorate, Egypt were microscopically identified and divided into 64 mosquito pools according to their genera and collection site. Single PCR was firstly conducted on mosquitoes followed by multiplex PCR for simultaneous detection of the three filarial parasites [Wucheraria bancrofti, Dirofilaria immitis, and Dirofilaria repens] and Wolbachia in mosquitoes. The results indicated that: Out of 64 mosquito pools, 8 pools were positive for Wuchererio bancrofti with estimated rate of infection [ERI 0.53%], 3 for each of Dirofilaria immitis and Dirofilaria repens [ERI 0.19%] and 6 pools were positive for Wolbachia [ERI 0.39%], five of them with filarial parasites [W. Bancrofti, D. immitis and D repens] [83.3%], with a significant P. value [< 0.05]. We concluded that there was a strong association between the presence of Wolbachia and filarial parasites that should be considered during the treatment of patients with filarial diseases by the use of specific anti-Wolbachia antibiotic in addition to the usual anti-filarial drugs