Short-term creatine supplementation changes protein metabolism signaling in hindlimb suspension

The effect of a short-term creatine supplementation on hindlimb suspension (HS)-induced muscle atrophy was investigated. Creatine monohydrate (5 g/kg b.w. per day) or placebo, divided in 2 daily doses, was given by oral gavage for 5 days. Rats were maintained in HS with dietary supplementation concomitantly for 5 days. Body weight, soleus and EDL muscle masses, and cross-sectional areas (CSA) of the muscle fibers were measured. Signaling pathways associated with skeletal muscle mass regulation (FST, MSTN, FAK, IGF-1, MGF, Akt, mTOR, atrogin-1, and MuRF1 expressions, and Akt, S6, GSK3B, and 4EBP1 proteins) were evaluated in the muscles. Soleus muscle exhibited more atrophy than the EDL muscle due to HS. Creatine supplementation attenuated the decrease of wet weight and increased p-4EBP1 protein in the EDL muscle of HS rats. Also, creatine increased mTOR and atrogin-1 expressions in the same muscle and condition. In the absence of HS, creatine supplementation increased FAK and decreased MGF expressions in the EDL muscle. Creatine attenuated the increase in FST expression due to HS in the soleus muscle. MuRF1 expression increased in the soleus muscle due to creatine supplementation in HS animals whereas atrogin-1 expression increased still further in this group compared with untreated HS rats. In conclusion, short-term creatine supplementation changed protein metabolism signaling in soleus and EDL muscles. However, creatine supplementation only slightly attenuated the mass loss of both muscles and did not prevent the CSA reduction and muscle strength decrease induced by HS for 5 days.

Mutation and genomic amplification of the PIK3CA proto-oncogene in pituitary adenomas

The tumorigenesis of pituitary adenomas is poorly understood. Mutations of the PIK3CA proto-oncogene, which encodes the p110-α catalytic subunit of PI3K, have been reported in various types of human cancers regarding the role of the gene in cell proliferation and survival through activation of the PI3K/Akt signaling pathway. Only one Chinese study described somatic mutations and amplification of the PIK3CA gene in a large series of pituitary adenomas. The aim of the present study was to determine genetic alterations of PIK3CA in a second series that consisted of 33 pituitary adenomas of different subtypes diagnosed by immunohistochemistry: 6 adrenocorticotropic hormone-secreting microadenomas, 5 growth hormone-secreting macroadenomas, 7 prolactin-secreting macroadenomas, and 15 nonfunctioning macroadenomas. Direct sequencing of exons 9 and 20 assessed by qPCR was employed to investigate the presence of mutations and genomic amplification defined as a copy number ≥4. Previously identified PIK3CA mutations (exon 20) were detected in four cases (12.1%). Interestingly, the Chinese study reported mutations only in invasive tumors, while we found a PIK3CA mutation in one noninvasive corticotroph microadenoma. PIK3CA amplification was observed in 21.2% (7/33) of the cases. This study demonstrates the presence of somatic mutations and amplifications of the PIK3CA gene in a second series of pituitary adenomas, corroborating the previously described involvement of the PI3K/Akt signaling pathway in the tumorigenic process of this gland.

MTP -493G/T gene polymorphism is associated with steatosis in hepatitis C-infected patients

The reduction of hepatic microsomal transfer protein (MTP) activity results in fatty liver, worsening hepatic steatosis and fibrosis in chronic hepatitis C (CHC). The G allele of the MTP gene promoter, -493G/T, has been associated with lower transcriptional activity than the T allele. We investigated this association with metabolic and histological variables in patients with CHC. A total of 174 untreated patients with CHC were genotyped for MTP -493G/T by direct sequencing using PCR. All patients were negative for markers of Wilson’s disease, hemochromatosis and autoimmune diseases and had current and past daily alcohol intake lower than 100 g/week. The sample distribution was in Hardy-Weinberg equilibrium. Among subjects with genotype 1, 56.8 percent of the patients with fibrosis grade 3+4 presented at least one G allele versus 34.3 percent of the patients with fibrosis grade 1+2 (OR = 1.8; 95 percentCI = 1.3-2.3). Logistic regression analysis with steatosis as the dependent variable identified genotypes GG+GT as independent protective factors against steatosis (OR = 0.4, 95 percentCI = 0.2-0.8; P = 0.01). The results suggest that the presence of the G allele of MTP -493G/T associated with lower hepatic MTP expression protects against steatosis in our CHC patients.

Estudo populacional da incidencia de patologias urologicas. / Populational study of the incidency of urologic diseases

Foram inspecionados 2702 candidatos a EFOMM e a EFRN no periodo de janeiro de 1981 a outubro de 1983 com uma faixa etaria entre 17 a 20 anos, e o estudo consistiu na determinacao de incidencia de patologia urologica a inspecao destes jovens.Os resultados obtidos vem de encontro a estudos anteriores (1, 2, 3) como a alta incidencia de fimose e varicocele. Mostra ainda a baixa incidencia de varicocele na raca negra e discute a grande desinformacao por parte da populacao com relacao a essas patologias e suas complicacoes

Cateter de Foley, estudo sobre a contaminacao do conteudo liquido do balao. / Catheter of Foley, study on the contamination foft the ballom liquid content

Os autores apresentam um estudo inicial "in vivo" e "in vitro" sobre a contaminacao do conteudo liquido do balao do cateter de Foley. A partir da observacao de que se encontrava turvo o liquido do balao foi realizada uma serie de culturas bacterianas comparativas do liquido do balao, estagnado no canal de irrigacao do cateter de tres vias e da urina de bexiga, concluindo que havia passagem de bacterias atraves dos poros do balao. Propoem o uso de substancias antissepticas no liquido de enchimento do balao a fim de evitar o aparecimento de um foco de infeccao