Riesgo de Desarrollo y Progresión de Cáncer Tiroideo Bien Diferenciado en pacientes con Variantes Genéticas del Gen de Tiroglobulina SER 734ala y ARG1980trp / Risk of Development and Progression of Well Differentiated Thyroid Cancer in patients with Genetic Variations of the Thyroglobulin SER734ala and ARG1980trp Genes

Introducción: Existen factores de riesgo que se asocian a desarrollo cáncer de tiroides diferenciado; la Tiroglobulina es una proteína ligada al tamaño tumoral, su rol dentro de las patologías oncológicas es controversial. El objetivo del estudio fue determinarsi las variaciones del gen de Tiroglobulina se asocian a la presencia de cáncer tiroideo. Métodos:Este estudio observacional de casos y controles se realizó con muestra no probabilística con muestras de patología de casos de cáncertiroideo diagnosticados en elHospital Oncológico Solón Espinosa Ayala de Quito. Se estableció un grupocontrol con voluntarios sanos. Se mide las variaciones SER734Ala y ARG1980 trp del gen de la Tiroglobulina. Se comparan las frecuencias con Chi cuadrado. Resultados:Un total de 51casos de cáncertiroideo y 50 controles. Variaciones en SER734Ala en el grupo de casos fueron homocigotos 24/51casos (53.3% (IC95% 38.8 -67.9%)en el grupo controlfueron24/50(53.3% (IC95% 38.8-67.9%)P=0.83. La variaciónheterocigotaARG1980 trp fueron en el grupo de casos 47/51(92.2%IC95% 84.3 -100%), en los controles 35/50(70% IC95% 56.6-83.4%)P=0.004. Conclusión:Se demostró que lasvariaciones del gen de laTiroglobulina pueden presentarse en pacientes con Cáncer Tiroideo en igual frecuencia que en voluntarios sanos

Introduction: There are risk factors associated with the development of differentiated thyroid cancer; Thyroglobulin is a protein linked to tumor size, its role in oncological pathologies is controversial. The objective of the study was to determine whether variations in the thyroglobulin gene are associated with the presence of thyroid cancer. Methods: This observational case-control study was conducted with a non-probabilistic sample with pathology samples from thyroid cancer cases diagnosed at the Solón Espinosa Ayala Oncological Hospital in Quito. A control group with healthy volunteers was established. The SER734Ala and ARG1980 trp variations of the Thyroglobulin gene are measured. The frequencies werecompared with Chi square. Results:A total of 51 thyroid cancer cases and 50 controls. Variations in SER734Ala in the group of cases were homozygous 24/51 cases (53.3% (CI95% 38.8 -67.9%) in the control group were 24/50 (53.3% (CI95% 38.8-67.9%) P = 0.83. Heterozygous ARG1980 trp were in the case group 47/51 (92.2% 95% CI 84.3 -100%), in the controls 35/50 (70% 95% CI 56.6-83.4%) P = 0.004. Conclusion:It was shown that variations of the Thyroglobulin gene couldoccur in patients with Thyroid Cancer in the same frequency as in healthy volunteers

Aspectos imunogenéticos do parto pré-termo espontâneo / Immunogenetic aspects in spontaneous preterm birth

O parto pré-termo é uma das grandes intercorrências obstétricas, sendo a maior causa de morbidade e mortalidade perinatal. Dentre os diferentes fatores envolvidos no seu desencadeamento, a infecção intra-amniótica parece representar um papel central. As infecções desencadeiam resposta inflamatória nos tecidos materno e fetal, mediada pela produção de citocinas inflamatórias. As citocinas induzem a liberação de prostaglandinas, aumentando a contratilidade uterina, favorecendo a rotura das membranas fetais, a modificação e dilatação da cérvice e, finalmente, o parto pré-termo. A síntese de citocinas depende de controle genético. Diversos polimorfismos relacionados a genes humanos codificadores de citocinas são reconhecidos e associados a fenótipos de alta, média e baixa produção desses fatores. Assim sendo, a relação entre determinados genótipos e a ocorrência e/ou características de diferentes patologias tem sido investigada. Este tipo de abordagem pode contribuir para o conhecimento da patogenia, permitindo o reconhecimento de parâmetros preditivos e a definição de novas estratégias terapêuticas.

Preterm birth is a major obstetric incident and one of the main causes of perinatal mortality and morbidity. Among the different factors involved in its unleashing, intra-amniotic infection seems to play a central role. The infections unleash inflammatory response in both maternal and fetal tissues, mediated by the production of inflammatory cytokines. They also lead to liberation of prostaglandin, which increases myometrial contractility, favoring the rupture of fetal membrane, alteration and dilation of the cervix and, finally, preterm birth. The production of cytokines depends on genetic control. Many polymorphisms related to human genes that codify cytokines are recognized and associated with phenotypes of high, medium and low production of such factors. Thus, the relation between certain genotypes and the occurrence and/or characteristics of several pathologies has been the focus of investigations. This approach may contribute with a better understanding of the pathogenesis, allowing the identification of predictive parameters and the establishment of new intervention strategies.

Characterization & evolutionary analysis of human CD36 gene.

Background and objectives: Understanding evolutionary genetic details of immune system genes responsible for infectious diseases is of prime importance concerning disease pathogenecity. Considering malaria as a devastating disease in the world including India, detail evolutionary understanding on human immune system gene is essential. The primary aim of this study was to initiate work on one such gene, the human CD36 gene responsible in malaria pathogenesis. Methods: DNA sequences of the human CD36 gene was retrieved from public domain and fifi ne-scale details were characterized. Both comparative and evolutionary analyses were performed with sequences from six other taxa (5 mammalian one avian) where CD36 homologs are present. Different statistical analyses were also performed. Results: Differential distribution in number and length of exons and introns was detected in CD36 gene across seven taxa. The CpG islands were also found to be distributed unevenly across the gene and taxa. Neighbour-joining tree was constructed and it was observed that the chimpanzee and human are diverged at the CD36 gene relatively recently. The chicken, Gallus gallus was found to be diverged from rest of the taxa signifi cantly. Also copy number variation was observed across different taxa. Interpretation & conclusions: Comparative genomic study of a human immune system gene CD36 show relationships among different taxa at the evolutionary level. The information can be of help to study genetic diversity in malaria endemic zones and to correlate it with malaria pathogenecity.

New approach for papaya latex storage without virus degradation / Nova metodologia de armazenamento do latex de mamão sem degradação viral

Papaya meleira virus (PMeV) is the causal agent of papaya (Carica papaya L.) sticky disease, which has been detected through analysis of its double-stranded RNA (dsRNA) genome from plant latex. In this work we demonstrate that PMeV dsRNA is protected during 25 days when latex is diluted in citrate buffer pH 5.0 (1:1 v/v) and maintained at -20ºC. At the same temperature, some protection was observed for pure latex or latex diluted in ultra-pure water. Conversely, the dsRNA was almost completely degraded after 25 days when maintained at 25ºC, indicating the need for freezing. The proper procedures to collect and store papaya latex described here will contribute to efficient and large scale use of molecular diagnosis of PMeV.

Papaya meleira virus (PMeV) é o agente etiológico da meleira do mamoeiro (Carica papaya L.), cujo diagnóstico é feito através da detecção do RNA dupla-fita (dsRNA) viral a partir do látex das plantas. Neste trabalho é demonstrado que o dsRNA do PMeV é protegido durante 25 dias quando diluído em tampão citrato pH 5.0 (1:1 v/v) seguido de armazenamento à -20ºC. Nesta mesma temperatura, o dsRNA foi parcialmente protegido quando o látex foi diluído em água ultra-pura ou mantido puro. Ao contrário, quando as amostras foram mantidas à 25ºC, observou-se uma degradação progressiva do dsRNA, com ausência de bandas após 25 dias, indicando a necessidade do congelamento do látex. Os procedimentos de coleta e armazenamento do látex descritos neste trabalho contribuem para a eficiência e uso em larga escala do diagnóstico molecular do PMeV.

Expressão de genes de resistência intrínsecos e adquiridos em Pseudomonas aeruginosas e funcionalidade de cassetes gênicos associados a integrons classe 1 / Expression of genes of intrinsic and acquired resistance in Pseudomonas aeruginosa and functionality of gene cassettes associated with class 1 integrons

Integrons classe 1 e cassetes gênicos vêm sendo apontados como importantes mecanismos para a emergência da multi-resistência em bactérias Gram-negativas, contudo, a maioria dos estudos não acessa a funcionalidade destas estruturas. Em Pseudomonas aeruginosas, os conhecidos sistemas de efluxo MexAB-OprM, MexCD-OprJ, MexEF-OprN e MexXY-OprM contribuem de forma significativa para multi-resistência, e a porina OprD tem sido considerado o principal determinante intrínseco de resistência a imipenem nesta espécie. Isolados clínicos de P. aeruginosas, Klebsiella pneumonie e Vibrio cholerae carreiam com freqüência integrons classe 1. O presente estudo tem como objetivo determinar o padrão de transcrição/expressão dos principais determinantes da multi-resistência em P. aeruginosas, incluindo mecanismos intrínsecos e adquiridos. Além disto, objetivou-se acessar o papel dos integrons e cassetes gênicos neste fenótipo de resistência em outras espécies, V. cholerae e K. pneumoniae, 17 isolados clínicos multi-resistentes de P. aeruginosas carreando íntegrons classe 1 com distintos arranjos gênicos foram analisados. Todo os arranjos gênicos, o gene da porina OprD e os genes reguladores das bombas foram seqüenciados. A transcrição de vários arranjos gênicos clonados (aacA4-blaoxa-2-gcuD, dfrB7-aacA4, dfrB7-aacA4-blaoxa-2 e aadB-aacA4-blacarb-4), dos quatro principais sistemas de efluxo (mexAB-oprM, mexAB-oprM, mexCD-oprJ, mexXY-oprM e mexEF-oprN) e do gene da porina oprD foi avaliada por PCR em tempo real. O padrão de transcrição do arranjo gcu14-blaGes1/aacA4 presente em PS1 e PS26 também foi determinado por PCR em tempo real e Northem blot. A expressão dos novos alelos de cassetes Gênicos encontrados em V. cholerae (qnrVC1), K. pneumoniae(arr-5) e P. aeruginosa (arr-4) foi verificada através do fenótipo de resistência e da busca de sinais traducionais presentes nestas estruturas. A maioria dos isolados apresentou aumento nos níveis de transcrição de mex XY, enquanto que mexEF-oprN estava reprimida em todos os isolados MexCD apresentou transcrição basal em 8/17 amostras e 4/17 estavam com transcrição elevada. OprD teve uma transcrição diminuída em grande parte dos isolados, corroborando com a resistência a imipenem observada, e alguns isolados com transcrição aumentada da oprD apresentavam várias mutações no gene estrutural. De um modo geral, os perfis de resistência estavam de acordo com a expressão de todas as bombas, contudo, a correlação entre a transcrição da bomba e a integridade de seu gene regulador não foi observada, indicando a participação de reguladores adicionais para todas estas quatro bombas. Há uma correlação entre o efeito da posição do cassete e o nível de transcrição, já que cassetes mais próximos do promotor Pc eram até 3X mais transcritos que cassetes mais distais. A influência da configuração do Pc nos níveis de transcrição também foi determinada, de forma que a versão forte foi responsável por um aumento de 2X em relação à versão fraca considerando o mesmo cassete gênico em uma mesma posição (aacA4). Foi mostrado que o cassete fusionado blages-1/aacA4 presente em PS1 e PS26 era transcrito como um RNAm policistrônico, e foi possível observar o efeito da posição do cassete. O fenótipo de resistência das transformantes corroborava com a expressão dos arranjos gênicos clonados. Promotores internos foram caracterizados em vários cassetes, e PaadB e Pcarb-4 mostraram ser funcionais. A presença da ORF-11 no sítio att/1 de vários dos cassetes gênicos e o fenótipo de resistência destes isolados sugere fortemente o papel desta seqüência regulatória putativa em eventos pós-transcricionais. Esta seqüência regulatória também foi identificada nos novos alelos descritos, qnrVC1, arr-4 e arr-5, e apóia o perfil de resistência observados nos isolados selvagens de V. cholerae, P.aeruginosa e K.pneumoniae. Além disso, foi identificada, pela primeira vez, uma ORF-11-like em potencial (ORF-15) que poderia aumentar a expressão dos cassetes dfrB7. Em conclusão, este estudo foi original na determinação do padrão de transcrição de cassetes fusionados, e no estabelecimento do efeito da posição do cassete no nível de transcrição em isolados selvagens de P. aeruginosa (PS1 e PS26). Verificou-se que a multi-resistência destes isolados era multifatorial, e que uma regulação pós-transcricional influenciava o fenótipo final de resistência. Considerando os isolados de P. aeruginosa, os cassetes gênicos em integrons de classe 1 tinham um papel secundário no perfil de resistência.

Advances in the studies of sperm protein 22 (SP22) / 中华男科学杂志

Multifunctional sperm protein 22 (SP22) is expressed ubiquitously and related to quite a few diseases. Located on the sperm surface, SP22 has an enzymatic activity that may assist sperm in penetrating into the ovum. SP22 may be carcinogenic in conspiracy with the factor ras. Among all species SP22 is highly conservative, which demonstrates its importance to life. More and more studies indicate that SP22 is directly correlated with male infertility and Parkinsons disease. This article summarizes recent researches on SP22 in the gene structure, protein structure and functional characteristics.

The structure, expression and function prediction of DAZAP2, a down-regulated gene in multiple myeloma / 基因组蛋白质组与生物信息学报·英文版

In our previous studies, DAZAP2 gene expression was down-regulated in untreated patients of multiple myeloma (MM). For better studying the structure and function of DAZAP2, a full-length cDNA was isolated from mononuclear cells of a normal human bone marrow, sequenced and deposited to Genbank (AY430097). This sequence has an identical ORF (open reading frame) as the NM_014764 from human testis and the D31767 from human cell line KG-1. Phylogenetic analysis and structure prediction reveal that DAZAP2 homologues are highly conserved throughout evolution and share a polyproline region and several potential SH2/SH3 binding sites. DAZAP2 occurs as a single-copy gene with a four-exon organization. We further noticed that the functional DAZAP2 gene is located on Chromosome 12 and its pseudogene gene is on Chromosome 2 with electronic location of human chromosome in Genbank, though no genetic abnormalities of MM have been reported on Chromosome 12. The ORF of human DAZAP2 encodes a 17-kDa protein, which is highly similar to mouse Prtb. The DAZAP2 protein is mainly localized in cytoplasm with a discrete pattern of punctuated distribution. DAZAP2 may associate with carcinogenesis of MM and participate in yet-to-be identified signaling pathways to regulate proliferation and differentiation of plasma cells.

A genome sequence of novel SARS-CoV isolates: the genotype, GD-Ins29, leads to a hypothesis of viral transmission in South China / 基因组蛋白质组与生物信息学报·英文版

We report a complete genomic sequence of rare isolates (minor genotype) of the SARS-CoV from SARS patients in Guangdong, China, where the first few cases emerged. The most striking discovery from the isolate is an extra 29-nucleotide sequence located at the nucleotide positions between 27,863 and 27,864 (referred to the complete sequence of BJ01) within an overlapped region composed of BGI-PUP5 (BGI-postulated uncharacterized protein 5) and BGI-PUP6 upstream of the N (nucleocapsid) protein. The discovery of this minor genotype, GD-Ins29, suggests a significant genetic event and differentiates it from the previously reported genotype, the dominant form among all sequenced SARS-CoV isolates. A 17-nt segment of this extra sequence is identical to a segment of the same size in two human mRNA sequences that may interfere with viral replication and transcription in the cytosol of the infected cells. It provides a new avenue for the exploration of the virus-host interaction in viral evolution, host pathogenesis, and vaccine development.

The E protein is a multifunctional membrane protein of SARS-CoV / 基因组蛋白质组与生物信息学报·英文版

The E (envelope) protein is the smallest structural protein in all coronaviruses and is the only viral structural protein in which no variation has been detected. We conducted genome sequencing and phylogenetic analyses of SARS-CoV. Based on genome sequencing, we predicted the E protein is a transmembrane (TM) protein characterized by a TM region with strong hydrophobicity and alpha-helix conformation. We identified a segment (NH2-_L-Cys-A-Y-Cys-Cys-N_-COOH) in the carboxyl-terminal region of the E protein that appears to form three disulfide bonds with another segment of corresponding cysteines in the carboxyl-terminus of the S (spike) protein. These bonds point to a possible structural association between the E and S proteins. Our phylogenetic analyses of the E protein sequences in all published coronaviruses place SARS-CoV in an independent group in Coronaviridae and suggest a non-human animal origin.

The R protein of SARS-CoV: analyses of structure and function based on four complete genome sequences of isolates BJ01-BJ04 / 基因组蛋白质组与生物信息学报·英文版

The R (replicase) protein is the uniquely defined non-structural protein (NSP) responsible for RNA replication, mutation rate or fidelity, regulation of transcription in coronaviruses and many other ssRNA viruses. Based on our complete genome sequences of four isolates (BJ01-BJ04) of SARS-CoV from Beijing, China, we analyzed the structure and predicted functions of the R protein in comparison with 13 other isolates of SARS-CoV and 6 other coronaviruses. The entire ORF (open-reading frame) encodes for two major enzyme activities, RNA-dependent RNA polymerase (RdRp) and proteinase activities. The R polyprotein undergoes a complex proteolytic process to produce 15 function-related peptides. A hydrophobic domain (HOD) and a hydrophilic domain (HID) are newly identified within NSP1. The substitution rate of the R protein is close to the average of the SARS-CoV genome. The functional domains in all NSPs of the R protein give different phylogenetic results that suggest their different mutation rate under selective pressure. Eleven highly conserved regions in RdRp and twelve cleavage sites by 3CLP (chymotrypsin-like protein) have been identified as potential drug targets. Findings suggest that it is possible to obtain information about the phylogeny of SARS-CoV, as well as potential tools for drug design, genotyping and diagnostics of SARS.