DNA damage and aging on hematopoietic stem cells: Impact of oxidative stress in ApoE-/- mice.

The effects of aging on ROS production and DNA damage were assessed in hematopoietic stem cells (HSCs) from apolipoprotein E-deficient (ApoE-/-) mice (2-, 12- and 24-month-old), a traditional experimental model of atherogenic dyslipidemia. HSCs from aged ApoE-/- mice were associated with increased ROS levels, leading to loss quiescence, DNA damage, apoptosis and telomere shortening. The concurrence of lack of ApoE and aging result in exhaustion and senescence of HSCs accompanied by increased oxidative stress and inflammation. Therefore, our data open avenues to a better understanding of age-related changes and genetic factors, which may synergistically compromise the efficacy of aged HSC recovery and/or transplantation.

Occult hepatitis B virus infection among blood donors from the Brazilian Amazon: implications for transfusion policy.

BACKGROUND: Brazil requires the performance of both a test for hepatitis B surface antigen (HBsAg) and a test for antibodies to the core of hepatitis B for blood donor screening. Blood centres in regions of high HBV endemicity struggle to maintain adequate stocks in face of the high discard rates due to anti-HBc reactivity. We evaluated the potential infectivity of donations positive for anti-HBc in search of a rational approach for the handling of these collections. STUDY DESIGN AND METHODS: We tested anti-HBc reactive blood donations from the state of Amazonas for the presence of HBV DNA and for titres of anti-HBs. The study population consists of village-based donors from the interior of Amazonas state. RESULTS: Among 3600 donations, 799 were anti-HBc reactive (22·2%). We were able to perform real-time PCR for the HBV S gene on specimens from 291 of these donors. Eight of these samples were negative for HBsAg and positive for HBV DNA and were defined as occult B virus infections (2·7%). Six of those eight specimens had anti-HBs titres above 100 mIU/ml, indicating the concomitant presence of the virus with high antibody titres. CONCLUSION: A small proportion of anti-HBc reactive donors carry HBV DNA and anti-HBs testing is not useful for predicting viremia on them. This finding indicates the possibility of HBV transmission from asymptomatic donors, especially in areas of high HBV prevalence. Sensitive HBV DNA nucleic acid testing may provide another level of safety, allowing eventual use of anti-HBc reactive units in critical situations.

B-cell epitopes of antigenic proteins in Leishmania infantum: an in silico analysis.

Serodiagnosis of visceral leishmaniasis is often hindered by cross-reactions to other parasitic diseases. Identifying specific B-cell epitopes in proteins is therefore important for immunodiagnostics, as well as for disease control by vaccines. This study aimed to identify linear and conformational B-cell epitopes and to evaluate the secondary structure of antigen proteins in Leishmania infantum using in silico analysis. Linear epitopes were predicted using the Immune Epitope Database and Analysis Resource (IEDB), BepiPred and BcePred programs. The conformational B-cell epitopes were identified using the CBTOPE server. The combination of the predictions using IEDB, BepiPred and BcePred generated 148 linear epitopes from the calpain-like cysteine peptidase (CP), thiol-dependent reductase 1 (TDR1) and HSP70 proteins. In total, 164 conformational epitopes were predicted, mostly located in the linear epitope region. The predicted epitopes are located in α helix and random coil regions in the thiol-dependent reductase 1 and HSP70 proteins. New linear and conformational B-cell epitopes of L. infantum proteins were identified in silico, and the prediction using various programs ensures greater accuracy of the results, as suggested by confirmation of previously identified HSP70 epitopes.

Ovicidal and larvicidal activity in vitro of Spigelia anthelmia Linn. extracts on Haemonchus contortus.

The rapid development of anthelmintic resistance, associated with the high cost of the available anthelmintic drugs, had limited the success of gastrointestinal nematodiasis control in sheep and goats and thus awakened interest in the study of medicinal plants as alternative sources of anthelmintics. Spigelia anthelmia extracts obtained with hexane, chloroform, ethyl acetate or methanol, were tested on Haemonchus contortus eggs and larvae via egg hatch and larval development tests. The extracts were evaluated at five concentrations: 3.1, 6.2, 12.5, 25.0 and 50.0 mg ml(-1). At 50.0 mg ml(-1), the ethyl acetate extract inhibited 100% of the egg hatching and 81.2% of the larval development. In a similar way the methanolic extract inhibited 97.4% of the egg hatching and 84.4% of larval development. These results suggest that utilization of S. anthelmia extracts may be useful in the control of sheep and goats gastrointestinal nematodes.

Anatomia patológica em 33 pacientes com epilepsia do lobo temporal / Anatomopathology in 33 patients with temporal lobo epilepsy

As crises parciais complexas do lobo temporal säo associadas a vários tipos de lesöes anátomo-patológicas, como esclerose mesial temporal, tumores, malformaçöes, infartos e infecçöes. Relataremos achados histopatológicos em 33 espécimes cirúrgicos consecutivos de pacientes com epilepsia temporal refratária a drogas antiepilépticas em todos, com exceçäo de 1 paciente. O único achado patológico em 20 deles foi esclerose mesial temporal, lesäo caracterizada por perda neuronal e gliose das estruturas mesiais do lobo temporal principalmente do hipocampo. Nove destes pacientes apresentaram crises nos 2 primeiros anos de vida, representadas por convulsöes febris complicadas em 8 deles, 4 traumatismos cranianos e 3 tiveram antecedentes de anorexia perinatal. A formaçäo hipocampal foi adequadamente estudada em 11 espécimes e se pôde verificar distribuiçäo näo uniforme das lesöes, as quais acometiam principalmente o setor de Sommer em 5, o hilo do giro denteado em 3 e estas duas regiöes nos outros 3 casos. Em 5 pacientes o hipocampo näo esteve disponível para análise e em outros 4 se encontrava destruído. Apenas 1 dos 13 pacientes desta série, com outras lesöes anátomo-patológicas, tinha antecedente de convulsäo febril. Os achados anátomo-patológicos destes 13 pacientes incluíram: Tumores (8 casos representados por gangliogliomas em 5, tumor neuroepitelial disembrioplástico em 1, astrocitoma pilocítico em 1 e oligodendrogioma em 1), microdisgenesia, granulomas cisticercótico e tuberculoso, hemossiderose e acúmulo de corpos psamomatosos. Este último achado foi considerado inespecífico

Intractable complex partial seizures associated with posterior cerebral artery giant aneurysm: a case report.

Giant aneurysms have rarely been reported in association with intractable complex partial seizures (CPS). We report a 30-year-old man with intractable CPS since age 18 years. Seizure onset was electrically localized to right temporal lobe. Preoperative neuroimaging studies showed a partially thrombosed giant aneurysm of the right posterior cerebral artery. Selective amygdalohippocampectomy and occlusion of the posterior cerebral artery did not cause deficits. The patient has been seizure-free for 15 months after operation. We review the relevant literature on aneurysms as a cause of epilepsy.

[Clinical manifestations in complex partial crisis of the temporal lobe: a video-electroencephalographic study]. / Manifestações clínicas de crises parciais complexas do lobo temporal: um estudo vídeo-eletrencefalográfico.

We analysed 27 complex partial seizures arising from the temporal lobes recorded on videotape simultaneously with the EEG emphasizing the motor manifestations specially dystonic posturing, ictal paresis and head and eye forced deviation (version). The temporal lobe origin of the seizures was based on the agreement of many scalp-sphenoidal or zygomatic interictal and ictal EEG recordings, CT and MRI findings, interictal and, in some patients, ictal SPECT studies. 8 patients had surgery. In 5 from 7 patients who had temporal lobectomy, mesial temporal sclerosis was the anatomopathological finding and in one patient who had selective amigdalohippocampectomy, hemosiderosis and gliosis probably due to bleeding of a posterior cerebral artery giant aneurysm was found. All patients have been seizure free after surgery. While dystonic posturing and ictal paresis, present in 18 seizures (66.6%), were excellent as lateralizing seizure signs, since they were always contralateral to the ictal onset, contralateral and ipsilateral versive head and eye movements were observed.

Características clínicas de pacientes com epilepsia temporal e esclerose mesial / Clinical characteristcs of patients with temporal lobe epilepsies and mesial sclerosis

Entre as epilepsias do lobo temporal, a síndrome temporal mesial é caracterizada por manifestaçöes clínicas homogêneas e achados específicos em exames paraclínicos. Descrevemos características clínicas de 22 pacientes, com 14 a 51 anos de idade (média 31,8 anos) e duraçäo da epilepsia de 6 a 41 anos (média 22,08 anos), com epilepsia do lobo temporal e sinais de esclerose mesial na RM e/ou no estudo anátomo-patológico. Crises epilépticas nos primeiros anos de vida estavam presentes em 19 (86,3 por cento ) dos pacientes; dentre estas, 11 foram convulsöes febris (em 10 complicados), as quais, quando apresentaram manifestaçöes motoras dimidiadas, constituíram importante dado para a lateriazaçäo da área epileptogênica, sendo sempre contralaterais ao lado da esclerose mesial temporal. Ocoreu intervalo livre de 8 meses a 24 anos (média 7,58 anos) entre o possível fator etiológico e o aparecimento de crises recorrentes sugestivas de epilepsia temporal, que incluiam crises parciais simples, com manifestaçöes viscerais, e crises parciais complexas, durante as quais sinais motores lateralizados foram importantes na lateralizaçäo do lobo epileptogênico de 9/71 pacientes. Crises tônico-clônicas generalizadas infreqüentes foram relatadas por 13 pacientes (59 por cento ), ocorrendo geralmente no início da epilepsia

Extracao e purificacao do hormonio de crescimento de hipofises humanas congeladas (hGH-HC). / Extration and purification of growth hormone from frozen human pituitaries (hGH-HC)

Os autores relatam a aplicacao de um metodo de extracao e purificacao de hormonio de crescimento obtido de hipofises humanas congeladas. O processo consiste em hemogeneizacao e extracao em buffer salino e precipitacao com alcool. O extrato e concentrado em Millipore e a purificacao realizada em duas colunas, Sephadex G-100 e DEAE celulose. Especial atencao foi dada a obtencao de um produto isento de pirogenio O controle de qualidade mostrou que se obteve um produto ativo, esteril, apirogenico e isento de antigeno Au que esta sendo aplicado no Hosptial das Clinicas da Universidade de Sao Paulo

Radioiodination of human growth hormone with characterization and minimization of the commonly defined "damaged products".

The radioiodination and chromatographic purification of human growth hormone (hGH) has been studied in order to better define and control the so-called "preparation damage", which is often a cause of interferences, loss in specific activity and sensitivity, misclassification errors in radioligand assays, and a source of misinterpretation when the tracer is used in receptors or in vivo studies. A series of labelings and false labelings, with and without protein carrier in the buffer used for Sephadex purification, indicate that the "preparation damage" peak is made up of two components: aggregated 125I-hGH and BSA-carried radioactivity. The former can be minimized by the use of recently extracted non-lyophilized hGH, and the latter by enzymatic labeling. Both components can be better resolved, and thus eliminated, when Sephadex G-100 is employed rather than G-75.

Familial dwarfism, high serum ria-GH and low somatomedin activity: an approach to pituitary LH secretory reserve.

Dois irmaos com sindrome de Laron foram estudados. A reserva secretoria pituitaria de LH foi estudada por meio do LHRH. Respostas sub-normais de LH ao estimulo com LHRH foram notadas, mas doses repetidas de LHRH produziram maior resposta de LH. Os niveis sericos de hormonio de crescimento (HC) eram altos, elevaram-se ainda mais apos estimulo com insulina e 90min apos o inicio do sono. Apos o GTT, os niveis de HC nao decresceram como o esperado. Os niveis basais de somatomedina (SM) eram baixos e nao aumentaram apos administracao de HC humano. Nao foram observadas alteracoes significativas no balanco metabolico apos administracao de HC humano. Um estudo genetico preliminar foi realizado, considerando 40 casos descritos na literatura