Experimental evidences that P21 protein controls Trypanosoma cruzi replication and modulates the pathogenesis of infection.

P21 is a protein secreted by Trypanosoma cruzi (T. cruzi). Previous studies have shown a spectrum of biological activities performed by P21 such as induction of phagocytosis, leukocyte chemotaxis and inhibition of angiogenesis. However, the activity of P21 in T. cruzi infection remains unknown. Here, we reported the role of P21 in mice harboring late T. cruzi infection. Treatment with recombinant P21 protein (rP21) reduced parasite load and angiogenesis, and induced fibrosis in the cardiac tissue of infected mice. In addition, rP21 reduced the growth of epimastigotes, inhibited intracellular replication of amastigotes and modulated the parasite cell cycle. Our data suggest that P21 controls parasite replication in the host, supporting the survival of both parasite and host.

Evaluation of apoptosis/necrosis and cytokine release provoked by three root canal sealers in human polymorphonuclears and monocytes.

AIM: To evaluate the in vitro cytotoxicity and cytokine release of three fresh root canal sealers and to determine the type of cell death they induce. METHODOLOGY: The sealers tested were Sealer 26 (S26), AH Plus (AHP), and Endosequence BC Sealer (END). Fresh sealers were cultivated in contact with monocytes and polymorphonuclears (PMNs) obtained from the peripheral blood of humans. Cell viability, apoptosis and necrosis were analysed at 4 h (PMNs) or 24 h (monocytes) using Annexin-V and propidium iodide in a cytometer. The supernatants were used to quantify Interleukin (IL)-4, IL-6, IL-10, IL-12 and tumour necrosis factor-α (TNF-α) in monocytes and IL-8 in PMNs by ELISA. One-way ANOVA and the Tukey post-test were used to compare data for cytotoxicity, and the multiple T-test was used to determine the differences between sealers in the release of cytokines that were statistically significant. RESULTS: After 4 h of treatment, S26 was associated with greater cell viability than the other sealers (P < 0.05) in the PMN culture and had similar values of necrosis as END (P > 0.05). After 24 h of treatment, AHP and END had greater monocyte cell viability than S26 (P < 0.05), which had more necrosis (P < 0.05). END had the lowest levels of IL-12 compared to the other sealers (P < 0.05) and higher levels of IL-6 compared to S26 (P < 0.05). The tested sealers did not differ in the release of IL-8, IL-10, TNF-α and IL-4 (P > 0.05). CONCLUSIONS: The effect of toxic agents released varied depending on the cell type studied. The composition of the sealers appeared to alter the form of self-regulation in the production of these cytokines by cells.

Experimental evidences that P21 protein controls Trypanosoma cruzi replication and modulates the pathogenesis of infection

P21 is a protein secreted by Trypanosoma cruzi (T. cruzi). Previous studies have shown a spectrum of biological activities performed by P21 such as induction of phagocytosis, leukocyte chemotaxis and inhibition of angiogenesis. However, the activity of P21 in T. cruzi infection remains unknown. Here, we reported the role of P21 in mice harboring late T. cruzi infection. Treatment with recombinant P21 protein (rP21) reduced parasite load and angiogenesis, and induced fibrosis in the cardiac tissue of infected mice. In addition, rP21 reduced the growth of epimastigotes, inhibited intracellular replication of amastigotes and modulated the parasite cell cycle. Our data suggest that P21 controls parasite replication in the host, supporting the survival of both parasite and host.

Experimental evidences that P21 protein controls Trypanosoma cruzi replication and modulates the pathogenesis of infection

P21 is a protein secreted by Trypanosoma cruzi (T. cruzi). Previous studies have shown a spectrum of biological activities performed by P21 such as induction of phagocytosis, leukocyte chemotaxis and inhibition of angiogenesis. However, the activity of P21 in T. cruzi infection remains unknown. Here, we reported the role of P21 in mice harboring late T. cruzi infection. Treatment with recombinant P21 protein (rP21) reduced parasite load and angiogenesis, and induced fibrosis in the cardiac tissue of infected mice. In addition, rP21 reduced the growth of epimastigotes, inhibited intracellular replication of amastigotes and modulated the parasite cell cycle. Our data suggest that P21 controls parasite replication in the host, supporting the survival of both parasite and host.

Extended preoperative chemotherapy, extent of liver resection and blood transfusion are predictive factors of liver failure following resection of colorectal liver metastasis.

AIM: The aim of this study was to determine the incidence and prognostic factors of postoperative liver failure in patients submitted to liver resection for colorectal metastases. METHOD: Patients with CLM who underwent hepatectomy from 1998 to 2009 were included in retrospective analysis. Postoperative liver failure was defined using either the 50-50 criteria or the peak of serum bilirubin level above 7 mg/dL independently. RESULTS: Two hundred and nine (209) procedures were performed in 170 patients. 120 surgeries were preceded by chemotherapy within six months. The overall morbidity rate was 53.1% and 90-day mortality was 2.3%. Postoperative liver failure occurred in 10% of all procedures, accounting for a mortality rate of 9.5% among this group of patients. In multivariate analysis, extent of liver resection, need of blood transfusion and more than eight preoperative chemotherapy cycles were independent prognostic factors of postoperative liver insufficiency. This complication was not related with the chemotherapy regimen used. CONCLUSION: We conclude that postoperative liver failure has a relatively low incidence (10%) after CLM resection, but a remarkable impact on postoperative mortality rate. The amount of liver resected, the need of blood transfusion and extended preoperative chemotherapy are independent predictors of its occurrence and this knowledge can be used to prevent postoperative liver failure in a multidisciplinary approach.

The role of iNOS and PHOX in periapical bone resorption.

Nitric oxide (NO) and reactive oxygen species (ROS) are key molecules in resistance to pathogens. Little is known about their role in pathogenesis of periapical lesions. To address this issue, we induced periapical lesions in mice lacking nitric oxide synthase (iNOS(-/-)) or phagocyte oxidase (PHOX(-/-)). iNOS(-/-) mice expressed higher levels of IL-1ß, TNF-α, RANK, RANKL, and MCP-1 than C57BL/6 and PHOX(-/-). Apical thickening of the periodontal ligament was also greater in iNOS(-/-) compared with other groups. Interestingly, ROS production did not interfere in periapical lesion progression, but seemed to be essential for the appearance of multinucleated TRAP-positive cells. Thus, periapical lesion progression in iNOS(-/-) was associated with an imbalance of pro-inflammatory cytokines (IL-1ß and TNF-α), bone-resorptive modulators (RANK and RANKL), and MCP-1. We conclude that NO, but not ROS, controls progression of bone resorption in a murine experimental model of apical periodontitis.

The interaction between N-category and N-ratio as a new tool to improve lymph node metastasis staging in gastric cancer: results of a single cancer center in Brazil.

BACKGROUND: Depth of tumor invasion (T-category) and the number of metastatic lymph nodes (N-category) are the most important prognostic factors in patients with gastric cancer. Recently, the ratio between metastatic and dissected lymph nodes (N-ratio) has been established as one. The aim of this study is to evaluate the impact of N-ratio and its interaction with N-category as a prognostic factor in gastric cancer. METHODS: This was a retrospective study in which we reviewed clinical and pathological data of 165 patients who had undergone curative surgery at our institution through a 9-year period. The exclusion criteria included metastases, gastric stump tumors and gastrectomy with less than 15 lymph nodes dissected. RESULTS: The median age of the patients was 63 years and most of them were male. Total gastrectomy was the most common procedure and 92.1% of the patients had a D2-lymphadenectomy. Their 5-year overall survival was 57.7%. T-category, N-category, extended gastrectomy, and N-ratio were prognostic factors in overall and disease-free survival in accordance with univariate analysis. In accordance with TNM staging, N1 patients who have had NR1 had 5-year survival in 75.5% whereas in the NR2 group only 33% of the cases had 5-year survival. In the multivariate analysis, the interaction between N-category and N-ratio was an independent prognostic factor. CONCLUSION: Our findings confirmed the role of N-ratio as prognostic factor of survival in patients with gastric cancer surgically treated with at least 15 lymph nodes dissected. The relationship between N-category and N-ratio is a better predictor than lymph node metastasis staging.

An in vivo experimental model to assess furcal lesions as a result of perforation.

AIM: To design and validate a rat molar model of furcal perforation to allow investigation of the biological phenomena that follow and to explore its potential for evaluating repair materials under standardized conditions. METHODOLOGY: Eighteen male Wistar rats were used. Surgical aseptic procedures were carried out in order to open the pulp chamber of a first molar tooth. A cavity was prepared on the floor of the pulp chamber using a (1/4) round bur that created a communication between the furcation and the periodontal tissues. Six animals for each time point were sacrificed on days 14, 21 and 28 to assay morphological changes at the furcation region of molars. Maxillary bone was processed, removed and sectioned. Cellular infiltration, collagen deposition and bone resorption were assessed by histological analysis. Cellularity in the lesion area was determined by morphometric analysis. Data were analysed using parametric Student's t-test. RESULTS: A furcal perforation model was standardized in which both radiological outcome and periodontal tissue reactions could be assessed through evaluation of cellularity, osteoclast activity and collagen deposition. The morphometric analysis revealed a greater number of cells 21 day post-surgery when compared with 14 days. CONCLUSION: This animal model was suitable for radiological and histological evaluation of the processes that accompany surgical furcal perforation.

Evaluation of a RAPD-based typing scheme in a molecular epidemiology study of Vibrio cholerae O1, Brazil.

AIMS: To evaluate the utility of random amplification of polymorphic DNA (RAPD) technique for routine practice in public health laboratories for epidemiological studies of Vibrio cholerae O1 isolates. MATERIALS AND RESULTS: Seventy-nine strains were examined by PCR for the toxin genes (ctx A, zot and ace), virulence-associated genes (tcp A and tox T) and RAPD sequences. Except for one strain (no. 1123) from the Amazonas State, all the strains analysed carried the genes ctx A, zot, ace, tcp A and tox T. RAPD fingerprinting revealed variability but no correlation with serotype, biotype or geographical origin of the isolates was found. CONCLUSION: A standardized RAPD method does not enable the establishment of a pattern data bank for the identification of V. cholerae O1 strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The simplicity and discriminative capacity of this technique make it useful for detecting genetic diversity among micro-organisms from a defined group or for outbreak investigation.

Comprometimento do sistema nervoso na leptospirose: I. Avaliaçäo dos aspectos neurológicos / Involvement of the nervous system in leptospirosis: I. Neurologic aspects evaluation

Entre 1-janeiro e 30-setembro-1990 foram estudados 77 pacientes com diagnóstico de leptospirose confirmada, laboratorialmente. Apresentaram início súbito dos sintomas 69 (89,61 por cento) pacientes, com febre, cefaléia, calafrios e mialgias. Observou-se envolvimento plurissistêmico quer nos pacientes ictéricos, quer nos anictéricos. O exame neurológico foi anormal em 70(90,91 por cento) pacientes, com achados variáveis e que, embora de caráter transitório, permitiram caracterizar as formas clínicas seguintes: meningoencefalite e polineurite associadas, meningoencefalite, polineurite e hemorragia subaracnóidea

Comprometimento do sistema nervoso na leptospirose: II. Avaliaçäo do líquido cefalorraqueano / Involvement of the nervous system in leptospirosis: II. Cerebrospinal fluid evaluation

Entre 1-janeiro e 30-setembro-1990 foram estudados 77 pacientes com diagnóstico de leptospirose, admitidos no SDIP/UFPE. O exame neurológico foi anormal em 70 (90,91 por cento) dos pacientes. O exame do LCR, foi realizado em 67 (87 por cento) dos pacientes, foi anormal em 64 (95,52 por cento), tendo como achado mais frequente a pleocitose. Näo houve diferença significativa no comportamento do LCR nas diversas formas clínicas neurológicas observadas, nem quando comparadas as formas ictéricas com as näo ictéricas. Bastante significativos foram os resultados da reaçäo de microaglutinaçäo para leptospirose no LCR

Comprometimento do sistema nervoso na leptospirose: III. Reaçöes imunológicas no sangue e líquido cefalorraqueano / Involvement of the nervous system in leptospirosis: III. Immunologic reactions in the blood and cerebrospinal fluid

Entre 1-janeiro e 30-setembro-1990 foram estudados 77 pacientes com diagnóstico de leptospirose: 64 (83,11 por cento) eram do sexo masculino e a média de idade, 28 anos. Os sorovars icterohemorrhagiae e canicola foram os mais frequentes. O exame do LCR, realizado em 67 (87,0 por cento) dos pacientes, foi anormal em 64 (95,52//). A reaçäo de microaglutinaçäo para leptospirose com antígenos vivos foi realizada no LCR, bem como reaçöes imunológicas para sífilis, cisticercose e esquistossomose para diagnóstico diferencial. Bastante signficativa foram os resultados da reaçäo de microaglutinaçäo para leptospirose no LCR, pela semelhança das respostas àquelas encontradas no sangue quanto à identificaçäo do sorovar