Homozygotes NAT2*5B slow acetylators are highly associated with hepatotoxicity induced by anti-tuberculosis drugs.

BACKGROUND: Distinct N-acetyltransferase 2 (NAT2) slow acetylators genotypes have been associated with a higher risk to develop anti-tuberculosis drug-induced hepatotoxicity (DIH). However, studies have not pointed the relevance of different acetylation phenotypes presented by homozygotes and compound heterozygotes slow acetylators on a clinical basis. OBJECTIVES: This study aimed to investigate the association between NAT2 genotypes and the risk of developing DIH in Brazilian patients undergoing tuberculosis treatment, focusing on the discrimination of homozygotes and compound heterozygotes slow acetylators. METHODS/FINDINGS: The frequency of NAT2 genotypes was analysed by DNA sequencing in 162 patients undergoing tuberculosis therapy. The mutation analyses revealed 15 variants, plus two new NAT2 mutations, that computational simulations predicted to cause structural perturbations in the protein. The multivariate statistical analysis revealed that carriers of NAT2*5/*5 slow acetylator genotype presented a higher risk of developing anti-tuberculosis DIH, on a clinical basis, when compared to the compound heterozygotes presenting NAT2*5 and any other slow acetylator haplotype [aOR 4.97, 95% confidence interval (CI) 1.47-16.82, p = 0.01]. CONCLUSION: These findings suggest that patients with TB diagnosis who present the NAT2*5B/*5B genotype should be properly identified and more carefully monitored until treatment outcome in order to prevent the occurrence of anti-tuberculosis DIH.

Homozygotes NAT2*5B slow acetylators are highly associated with hepatotoxicity induced by anti-tuberculosis drugs

BACKGROUND Distinct N-acetyltransferase 2 (NAT2) slow acetylators genotypes have been associated with a higher risk to develop anti-tuberculosis drug-induced hepatotoxicity (DIH). However, studies have not pointed the relevance of different acetylation phenotypes presented by homozygotes and compound heterozygotes slow acetylators on a clinical basis. OBJECTIVES This study aimed to investigate the association between NAT2 genotypes and the risk of developing DIH in Brazilian patients undergoing tuberculosis treatment, focusing on the discrimination of homozygotes and compound heterozygotes slow acetylators. METHODS/FINDINGS The frequency of NAT2 genotypes was analysed by DNA sequencing in 162 patients undergoing tuberculosis therapy. The mutation analyses revealed 15 variants, plus two new NAT2 mutations, that computational simulations predicted to cause structural perturbations in the protein. The multivariate statistical analysis revealed that carriers of NAT2*5/*5 slow acetylator genotype presented a higher risk of developing anti-tuberculosis DIH, on a clinical basis, when compared to the compound heterozygotes presenting NAT2*5 and any other slow acetylator haplotype [aOR 4.97, 95% confidence interval (CI) 1.47-16.82, p = 0.01]. CONCLUSION These findings suggest that patients with TB diagnosis who present the NAT2*5B/*5B genotype should be properly identified and more carefully monitored until treatment outcome in order to prevent the occurrence of anti-tuberculosis DIH.

PGAM1 and TP53 mRNA levels in canine mammary carcinomas - Short communication.

TP53 and PGAM1 genes play a key role in glycolysis which is an essential metabolic pathway of cancer cells for obtaining energy. The purpose of this work was to evaluate PGAM1 and TP53 mRNA expressions in canine mammary carcinomas (CMC) and to correlate them with animal data and tumour histological features. None of the nine samples analysed revealed PGAM1 DNA sequence variations. PGAM1 and TP53 RNA expressions from 21 CMC were analysed using a one-step reverse transcription-PCR kit and its platform system. Most CMC samples had low levels of PGAM1 mRNA (71.5%) and normal expression of TP53 mRNA (95.2%). Our results suggest a different feature of the Warburg effect on canine mammary cancer cells compared to human cells.

Epidermal growth factor receptor 2 immunoexpression in gastric cells of domestic cats with H. heilmannii infection.

The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate.

ACTN3 gene variants as potential phenotype and performance biomarkers in Brazilian sport horses training for eventing in a tropical climate.

The aim of this study was to look for mutations in the equine ACTN3 gene and to identify sequence variants that might be associated with the phenotype and performance of Brazilian sport horses training for events in a tropical climate. Among 17 such horses direct DNA sequencing and mutation analysis of the exon 15 and the intron-exon boundaries of ACTN3 revealed 2 new sequence variants in the ACTN3 intron 14-15, designated c.1681-86G > A and c.1681-129delA. Wild-type/deletion heterozygotes (A/del) had a lower mean subcutaneous fat layer in the region of the gluteus medius, as measured by ultrasonography, than the del/del homozygotes; the correlation was significant (P = 0.017). This single base-pair deletion in ACTN3 intron 14-15 may have resulted in metabolic changes that led to increased deposition of body fat in the homozygous state. However, neither sequence variant was correlated with the time to fatigue in a test on a high-speed treadmill with an incremental-speed protocol.

Le but de la présente étude était de vérifier pour la présence de mutations dans le gène ACTN3 équin et d'identifier des variants de séquence qui pourraient être associés avec le phénotype et la performance de chevaux de sport brésiliens qui s'entraînent pour des concours dans un climat tropical. Parmi 17 chevaux qui correspondent à ces critères, le séquençage direct de l'ADN et l'analyse de mutation de l'exon 15 et des frontières de l'intron-exon d'ACTN3 a révélé deux nouveaux variants de séquence dans l'intron 14­15 d'ACTN3, désigné c.1681­86G > A et c.1681­129delA. Chez les hétérozygotes type-sauvage/délétion (A/del) la moyenne de l'épaisseur de la couche de gras sous-cutané dans la région du gluteus medius était plus petite, telle que mesurée par échographie, que celle des homozygotes del/del; la corrélation était significative (P = 0,017). Cette délétion unique de paire de bases dans l'intron 14­15 d'ACTN3 pourrait avoir résulté dans des changements métaboliques qui auraient mené à une augmentation du dépôt de gras chez les homozygotes. Toutefois, aucun des variants de séquence n'était corrélé avec le temps de fatigue dans un test sur un tapis-roulant à haute vitesse avec un protocole d'augmentation de vitesse.(Traduit par Docteur Serge Messier).

Effect of selection for eventing on the MSTN gene in Brazilian sport horses.

Polymorphisms in MSTN have previously been associated with equine performance. Therefore, the aim of this study was to identify variants in MSTN intron 1 in 16 Brazilian Sport Horses selected for competition in eventing and their possible effects of selection on performance. Among the nine variants identified, eight had already been reported in previous studies or genomic databases, although they showed differences in frequencies when compared with other horse breeds. Moreover, a new mutation was identified in two horses, both in heterozygous form. Considering the absence of molecular studies in this valuable Brazilian breed, these findings represent an important contribution to the characterization of its genetic profile and may possibly aid in further genotype-phenotype association studies.

Molecular analysis of holoprosencephaly in South America.

Holoprosencephaly (HPE) is a spectrum of brain and facial malformations primarily reflecting genetic factors, such as chromosomal abnormalities and gene mutations. Here, we present a clinical and molecular analysis of 195 probands with HPE or microforms; approximately 72% of the patients were derived from the Latin American Collaborative Study of Congenital Malformations (ECLAMC), and 82% of the patients were newborns. Alobar HPE was the predominant brain defect in almost all facial defect categories, except for patients without oral cleft and median or lateral oral clefts. Ethmocephaly, cebocephaly, and premaxillary agenesis were primarily observed among female patients. Premaxillary agenesis occurred in six of the nine diabetic mothers. Recurrence of HPE or microform was approximately 19%. The frequency of microdeletions, detected using Multiplex Ligation-dependant Probe Amplification (MLPA) was 17% in patients with a normal karyotype. Cytogenetics or QF-PCR analyses revealed chromosomal anomalies in 27% of the probands. Mutational analyses in genes SHH, ZIC2, SIX3 and TGIF were performed in 119 patients, revealing eight mutations in SHH, two mutations in SIX3 and two mutations in ZIC2. Thus, a detailed clinical description of new HPE cases with identified genetic anomalies might establish genotypic and phenotypic correlations and contribute to the development of additional strategies for the analysis of new cases.