Structure, expression, and biological function of INSM1 transcription factor in neuroendocrine differentiation

Zinc-finger transcription factors are DNA-binding proteins that are implicated in many diverse biological functions. INSM1 (formerly IA-1) contains five zinc-finger motifs and functions as a transcription factor. INSM1 protein structure is highly conserved in homologues of different species. It is predominantly expressed in developing neuroendocrine tissues and the nervous system in mammals. INSM1 represents an important player in early embryonic neurogenesis. In pancreatic endocrine cell differentiation, Ngn3 first activates INSM1 and subsequently NeuroD/β2. Conversely, INSM1 exerts a feedback mechanism to suppress NeuroD/β2 and its own gene expression. INSM1 gene ablation in the mouse results in the impairment of pancreatic endocrine cell maturation. Further, deletion of INSM1 severely impairs catecholamine biosynthesis and secretion from the adrenal gland that results in early embryonic lethality. Genetically, INSM1 acts as a downstream factor of Mash 1 and Phox2b in the differentiation of the sympatho-adrenal lineage. In the developing neocortex, mouse embryos lacking INSM1 expression contain half the number of basal progenitors and show a reduction in cortical plate radial thickness. Cell signaling studies reveal that INSM1 contributes to the induction of cell cycle arrest/exit necessary to facilitate cellular differentiation. INSM1 is highly expressed in tumors of neuroendocrine origin. Hence, its promoter could serve as a tumor-specific promoter that drives a specific targeted cancer gene therapy for the treatment of neuroendocrine tumors. Taken together, all of these features of INSM1 strongly support its role as an important regulator during neuroendocrine differentiation.—Lan, M. S., Breslin, M. B. Structure, expression, and biological function of INSM1 transcription factor in neuroendocrine differentiation

Ocorrência do subtipo B do vírus da imunodeficiência felina em gatos domésticos da região sul do estado do Rio Grande do Sul, Brasil

In Brazil there are few studies on the occurrence of the feline immunodeficiency virus (FIV) infection and its subtypes, which are essential for the development of vaccines and new diagnostic tests. The present study investigated the occurrence of the FIV infection between 2010 and 2011 in domestic cats submitted to medical attendance in the city of Pelotas and nearby area. Total blood samples of seventy cats, suspected (28) or not (42) of infection by FIV were analyzed by nested PCR in order to perform a diagnosis. The results pointed to a FIV infection frequency of 15.7% (11/70) and the analysis of the risk factors related to infection (sex, age and clinical condition) evidenced a greater occurrence in cats up to 10 years of age with chronic and recurrent infections. Eight samples found positive by nested PCR were submitted to DNA sequencing indicating that only the subtype B was detected in the studied region.No Brasil existem poucos estudos sobre a ocorrência da infecção pelo vírus da imunodeficiência felina (FIV), assim como a determinação dos subtipos circulantes, o que é indispensável para o desenvolvimento de vacinas e novos testes diagnósticos. O presente trabalho investigou a ocorrência da infecção pelo FIV entre os anos de 2010 e 2011 em gatos domésticos submetidos a atendimento clínico na cidade de Pelotas e região. Amostras de sangue total de 70 animais, incluindo suspeitos (28) ou não suspeitos (42) da infecção pelo FIV, foram submetidas à reação de PCR nested. Os resultados indicaram uma frequência de infecção de 15,7% (11/70) e a análise dos fatores associados (sexo, idade e condição clínica) evidenciou uma maior ocorrência em gatos com idade superior a 10 anos e acometidos por infecções crônicas e recidivantes. Oito amostras positivas na PCR nested foram submetidas a sequenciamento genômico e somente o subtipo B foi detectado na região estudada

Ocorrência, aspectos toxicológicos, métodos analíticos e controle da patulina em alimentos Occurrence, toxicological aspects, analytical methods and control of patulin in food

A patulina é uma micotoxina produzida por várias espécies de Penicillium, Aspergillus e Byssochlamys. Em experimentos com animais, ela demonstrou ter atividade mutagênica, carcinogênica e teratogênica. Tem sido freqüentemente encontrada em maçãs e derivados. A patulina é facilmente transferida da maçã para o suco durante o processamento devido a sua alta solubilidade em água. Essa micotoxina é muito estável ao aquecimento em meio ácido, como no suco de maçã. Assim, a presença de patulina em suco de maçã é um indicador da qualidade das maçãs utilizadas no processamento. Muitos métodos têm sido desenvolvidos para a determinação da patulina, principalmente baseados na extração líquido-líquido com acetato de etila e determinação por CLAE. É importante evidenciar a necessidade de legislação que regulamente limites dessa micotoxina em alimentos no Brasil. Esta revisão bibliográfica tem como objetivos descrever as principais características da patulina, a ocorrência, os aspectos toxicológicose os métodos desenvolvidos para sua detecção e controle durante os estágios da produção da maçã e suco.<br>Patulin is a mycotoxin produced by several Penicillium, Aspergillus and Byssochlamys species. Patulin is a highly toxic compound which has shown to be mutagenic, carcinogenic and teratogenic in experiments with animals. It has often been found in apples and apple products. Patulin is easily transfered into apple juice during processing due to its high solubility in water. This mycotoxin is very stable to heat in acidic medium as in apple juice. Thus, patulin content of apple juice is an indicator of the quality of the apples used to juice production. Many methods have been developed for the patulin determination mainly based on liquid-liquid extraction with ethyl acetate and use of HPLC for detection. It is important to show the need of legislation that imposes patulin limits in foods in Brazil. The objectives of this review are to describe the main patulin characteristics, occurrence, toxicological aspects, methods developed for patulin detection and control during the stages of apple and juice production