Cobalamin cbiP mutant shows decreased tolerance to low temperature and copper stress in Listeria monocytogenes.

BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature + copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis-related genes (cbiP, cbiB, and cysG) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) + copper (0.5 mM of CuSO4 × 5H2O). In addition, the gene cbiP, which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) + different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP, cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature + copper. The cobalamin cbiP mutant strain List2-2ΔcbiP showed less tolerance to low temperature + copper (3 mM) than the wild-type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2ΔcbiP. CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature + copper.

Cobalamin cbiP mutant shows decreased tolerance to low temperature and copper stress in Listeria monocytogenes

BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature +copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis related genes ( cbiP , cbiB, and cysG ) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) +copper (0.5 mM of CuSO4 ×5H2O). In addition, the gene cbiP , which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) +different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP , cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature +copper. The cobalamin cbiP mutant strain List2-2Δ cbiP showed less tolerance to low temperature +copper (3 mM) than the wild type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2Δ cbiP . CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature +copper.

Early manifestations of autism spectrum disorders. Experience of 393 cases in a paediatric neurology.

INTRODUCTION: Autism spectrum disorders are group of conditions characterised by qualitative impairments in social communication, interaction, and imagination, and by a restricted range of interests and typical repetitive behaviours. Frequently, there is a delay in the age of detection, and therefore in starting multidisciplinary evaluations and interventions, which may result in a poorer prognosis and reduced quality of life for both children and parents. The aim of our study was to describe clinical and epidemiological data including the age of detection and main initial complaints present in children with autism disorders referred to a paediatric neurology centre. PATIENTS AND METHODS: A total of 393 medical records of consecutive cases diagnosed with an autism spectrum disorder were reviewed. RESULTS: Autism was diagnosed in 82.1% of the cases, unspecified pervasive disorder in 9.9%, Asperger syndrome in 4.8%, and Rett syndrome in 3%. Sixty percent of autistic children presented with a language disorder as their main complaint. The average age of detection was 4 years. CONCLUSIONS: Compared with other countries, age of detection is delayed. Primary care-based screening and surveillance are required in order to improve prognosis and quality of life of children with an autism spectrum disorder.

Efecto de la infección periodontal por porphyromonas gingivalis en el desarrollo de ateroesclerosis en ratones deficientes de apolipoproteína E / Effects of porphyromona gingivalis periodontal infection upon atherosclerosis development in apolipoprotein-E

Introducción: Nuestro grupo recientemente demostró una asociación significativa entre periodontitis, placas coronarias aguda y extensión de la enfermedad coronaria aterosclerótica en pacientes con síndrome coronario agudo. Objetivo: Desarrollar un modelo experimental animal para estudiar el posible efecto pro-aterogénico de la inducción de periodontitis por Porphyromona Gingivalis (PG) en ratones deficientes en la apolipoproteína E (APO-E KO). Métodos: En 12 ratones APO-E KO mantenidos con dieta hiperlipidémica se realizaron tocaciones con PG cepa ATCC 53977 en el surco gingival de los molares mandibulares a las 8 semanas de vida. Igual número de ratones APO-E KO fue intervenido con el mismo procedimiento, pero sólo con el vehículo de las tocaciones. Estos procedimientos se repitieron a las 48, 72 y 120 hrs de la infección inicial. Luego de 4 semanas post-inoculación con PG se realizaron estudios histomorfométricos en la aorta proximal para medir la severidad de las lesiones ateromatosas y en las mandíbulas, para evaluar la pérdida del hueso alveolar. Resultados: No se observó una diferencia significativa en el daño del hueso alveolar en las mandíbulas de los animales infectados versus el grupo control. En las aortas, la razón tamaño placa/pared vascular fue mayor en el grupo infectado con PG que en el grupo control (0.132 ± 0.2 versus 0.103 ± 0.15, respectivamente), pero esta diferencia no fue estadísticamente significativa. Conclusión: El diseño experimental del presente estudio no permitió establecer si la periodontitis inducida por PG es capaz o no de acelerar el proceso aterogénico de los ratones APO-E KO. Será necesario aplicar un protocolo de infección periodontal más agresivo en estos animales para evaluar más adecuadamente el efecto de PG sobre la ateroesclerosis.

Histomorphometry of normal and abnormal endometrial samples.

One hundred forty samples of normal and pathological endometrium were examined morphometrically in order to achieve a discriminant function among normal and pathological diagnoses. Samples of proliferative and secretory normal endometrium, simple and atypical hyperplasia, and well-differentiated adenocarcinoma were included in this study. Morphometrical and stereological characteristics for both glands and lumina as well as epithelium were registered. Stepwise discriminant analysis was performed. There is an increase in size of glands from proliferative endometrium to well-differentiated adenocarcinoma. The stereological measurements parallel morphometrical measurements. The accuracy of diagnosis by morphometrical and stereological means were 91% when the normal group (proliferative and secretory phase) were included. Accuracy increases to 95% when only three pathological groups were used; only one simple hyperplasia and one well-differentiated adenocarcinoma were incorrectly diagnosed. In all functions, the volume density of epithelium was selected. The reproducibility on a new data set demonstrates an efficiency of 92, 87, and 100% for three discriminant analyses (five, four, and three diagnostic groups, respectively).

[A synchronous association of a double colonic adenocarcinoma and hypernephroma: an infrequent case of multiple primary neoplasms]. / Asociación sincrónica de doble adenocarcinoma de colon e hipernefroma: un caso infrecuente de neoplasia primitiva múltiple.

It has been reported that exceptional association exists between primary colon cancer and hypernephroma. In this paper we are reporting a case of a male patient carrying an hypernephroma synchronous with a proximal colonic adenocarcinoma in addition to a second adenocarcinoma, growing on a tubular adenoma, nearly of first. These findings get seen as partially coincidental with some features of the cancer family syndrome (Lynch syndrome II), and we have considered that genetics conditions, like those of Lynch syndrome II, could to explain some multiple neoplasms in patients carrying then.