Fábio Oliveira

BACKGROUND Colorectal cancer (CRC) is a worldwide health problem whose control depends on public policy establishment and effective prevention and screening programs. In Brazil, there are few studies related to adherence to screening methods. AIMS The aim of this study was to evaluate the association between demographic and socioeconomic to adhere...

Dengue fever is considered a major public health problem in tropical and subtropical regions. Our study analyzed the effect of BaltPLA2, a phospholipase A2 from Bothrops alternatus snake venom, on the viability of cells infected with Dengue virus. In presence of BaltPLA2, the viability of infected cells increased significantly in virucidal, post-tr...

C-type lectin-like proteins found in snake venom, known as snaclecs, have important effects on hemostasis through targeting membrane receptors, coagulation factors and other hemostatic proteins. Here, we present the isolation and functional characterization of a snaclec isolated from Bothrops alternatus venom, designated as Baltetin. We purified th...

Snakebite accidents are considered serious public health problems. They are often neglected, and individuals who have received insufficient treatment are subjected to various disabling alterations. Snake venoms are secretions composed of biologically active molecules capable of triggering local and systemic effects in envenomation victims. Bothropi...

Ophidic accidents are among the problems of public health in Brazil. The components from bothropic venom are responsible for many systemic clinical complications resulting from envenomation. The present work aimed to analyse the systemic changes induced in mice after intraperitoneal administration of BmooTX‐I, a myotoxic acidic phospholipase A2 iso...

Background: In last decades, snake venoms have aroused great interest of the medicine due to the pathophysiological effects caused by their toxins. These include the phospholipases A2, low molecular weight proteins capable of causing haemorrhagic, myotoxic, inflammatory and neurotoxic effects after an ophidian accident. The present work describes...

Phospholipases A2 represent a family of enzymes with important application in medicine. However, direct tracking is difficult due to the absence of a stable, effective and specific marker for these enzymes. Magic-sized quantum dots (MSQDs) are inorganic semiconducting nanocrystals with unique physical properties. They have the ability to conjugate...

Purpose: Patients with cancer of the lower and middle rectum who are candidates for curative surgery often have negative opinions on definitive colostomy. The purpose of this study is to compare the quality of life (QoL) of patients who undergo standard treatment for rectal cancer with sphincter preservation or definitive colostomy. Methods: A t...

Background Snake venoms are a complex mixture of proteins, organic and inorganic compounds. Some of these proteins, enzymatic or non-enzymatic ones, are able to interact with platelet receptors, causing hemostatic disorders. The possible therapeutic potential of toxins with antiplatelet properties may arouse interest in the pharmacological areas. T...

Colorectal cancer (CRC) is a neoplasia with high incidence and mortality rates. It had been suggested that the inflammatory response is an important CRC prognostic factor. The disordered and accelerated proliferation of neoplastic cells decreases the oxygen and nutrient supply, generating a microenvironment characterized by hypoxia, necrosis and in...

This work reports the purification and functional characterization of BmooPAi, a platelet-aggregation-inhibiting factor from Bothrops moojeni snake venom. The toxin was purified by a combination of three chromatographic steps (ion-exchange on DEAE-Sephacel, molecular exclusion on Sephadex G-75, and affinity chromatography on HiTrap™ Heparin HP). Bm...

The incidence of colorectal cancer (CRC) is lower in women than in men, and sex steroids can be considered contributing factors because oral contraception usage and estrogen replacement therapy are associated with decreased risk. Conversely, colorectal polyp development in familial adenomatous polyposis (FAP) begins during puberty. The objectives w...

The human body has a set of physiological processes, known as hemostasis, which keeps the blood fluid and free of clots in normal vessels; in the case of vascular injury, this process induces the local formation of a hemostatic plug, preventing hemorrhage. The hemostatic system in humans presents complex physiological interactions that involve plat...

Phospholipase A2 inhibitors (PLIs) are important targets in the search and development of new drugs. This study aimed at evaluating the potential of an alpha-type phospholipase A2 inhibitor from Bothrops alternatus (Rhinocerophis alternatus) snake in its recombinant form (rBaltMIP) to complement the conventional antivenom therapy. Biochemical exper...

Bothropic envenomation is characterised by severe local damage caused by the toxic action of venom components and aggravated by induced inflammation. In this comparative study, the local inflammatory effects caused by the venoms of B. alternatus and B. moojeni, two snakes of epidemiological importance in Brazil, were investigated. The toxic action...

In this work, we describe the purification and characterization of a new serine protease enzyme from Bothrops moojeni snake venom (BmooSP). On SDS-PAGE, BmooSP was found to be a single-chain protein with an apparent molecular mass of 36,000 and 32,000 under reduced and non-reduced conditions, respectively. Mass spectrometry analysis showed that the...

Mammalian semen chromatin comprises DNA, protamine, and, at lower levels, other proteins. This constitution confers intense compaction to the chromatin, helping to protect the DNA and causing the head of the sperm to be very small, facilitating the safe transport of its genetic contents. It is known that changes in the sperm chromatin compaction le...

In this study, we evaluated the edema and hyperalgesic response induced by BpirMP, a P-I class metalloproteinase isolated from Bothrops pirajai snake venom. The animals were injected with the metalloproteinase or sterile PBS (control group) and evaluated for 1, 2, 3, 4, 5, 6 and 24h. The intraplantar injection of BpirMP (5-50μg/paw) induced a dose-...

Lynch syndrome (LS) accounts for 3-5% of all colorectal cancers (CRC) and is inherited in an autosomal dominant fashion. This syndrome is characterized by early CRC onset, high incidence of tumors in the ascending colon, excess of synchronous/metachronous tumors and extra-colonic tumors. Nowadays, LS is regarded of patients who carry deleterious ge...

Venomous and non-venomous snakes possess phospholipase A2 (PLA2) inhibitory proteins (PLIs) in their blood serum. This study shows the expression and biochemical and functional characterization of a recombinant alpha inhibitor from Bothrops alternatus snake, named rBaltMIP. Its expression was performed in Pichia pastoris heterologous system, result...

We present the biochemical and functional characterization of Bothropoidin, the first haemorrhagic metalloproteinase isolated from Bothrops pauloensis snake venom. This protein was purified after three chromatographic steps on cation exchange CM-Sepharose fast flow, size-exclusion column Sephacryl S-300 and anion exchange Capto Q. Bothropoidin was...

Method for the production of a closed edge refractory foam filter, by providing a reticulated foam substrate having at least one first surface for forming a side face of the filter and two opposed second surfaces for forming the through-flow faces of the filter, applying a liquid including an organic coating component to the first surface, solidify...

The present study aimed to evaluate the proteolytic and biological activities of a new metalloproteinase from B. moojeni venom. The purification of BmooMP α -II was carried out through two chromatographic steps (ion-exchange and affinity). BmooMP α -II is a monomeric protein with an apparent molecular mass of 22.5 kDa on SDS-PAGE 14% under nonreduc...

In this paper, we describe the purification/characterization of BmooAi, a new toxin from Bothrops moojeni that inhibits platelet aggregation. The purification of BmooAi was carried out through three chromatographic steps (ion-exchange on a DEAE-Sephacel column, molecular exclusion on a Sephadex G-75 column, and reverse-phase HPLC chromatography on...

Muscular necrosis is a serious consequence of Bothrops snake bites that may lead to permanent loss of tissue or function. Myonecrosis may be due to injury to blood vessels, destabilization and/or rupture of plasma membrane, and inflammatory mechanisms triggered by different proteins from the snake venom. In this work we describe the isolation and p...

A fibrinogenolytic metalloproteinase from Bothrops moojeni venom, named moojenin, was purified by a combination of ion-exchange chromatography on DEAE-Sephacel and gel filtration on Sephacryl S-300. SDS-PAGE analysis indicated that moojenin consists of a single polypeptide chain and has a molecular mass about 45 kDa. Sequencing of moojenin by Edman...

10069 Background: Treatment of soft tissue sarcomas (STS) is characterized by high rates of local control, but poor overall survival because of distant relapses and high rates of wound complications, when preoperative radiation is used. The objective of this study was to test the effectiveness of a protocol with neoadjuvant chemotherapy for STS. Me...

e14119 Background: A select group of patients with peritoneal carcinomatosis (PC) has been treated with curative intent by cytoreductive surgery (CCS) associated with intraperitoneal hyperthermic chemotherapy (HIPEC). The objective of this study is to identify predictors of postoperative complications in patients undergoing CCS + HIPEC. Methods: We...

Cognitive decline in Alzheimer disease (AD) is increasingly attributed to the neuronal impact of soluble oligomers of the amyloid-β peptide (AβOs). Current knowledge on the molecular and cellular mechanisms underlying the toxicity of AβOs stems largely from rodent-derived cell/tissue culture experiments or from transgenic models of AD, which do not...

Background: Soluble Aβ oligomers (AβOs) have been increasingly proposed as the cause of synapse failure and cognitive dysfunction in Alzheimer disease. Results: Sublethal AβO concentrations induce changes in gene expression in adult human brain slices. Conclusion: AβOs impact transcription in important neuronal pathways preceding neurodegeneration....

Topoisomerase 2 alpha (TOP2A), HER-2/neu, and survivin are genes that lie on chromosome 17 and correlate with the prognosis and prediction of target-driven therapy against tumors. In a previous study, we showed that TOP2A transcripts levels were significantly higher in soft tissue sarcomas (STS) than in benign tumors and desmoid-type fibromatoses (...

PURPOSE To evaluate the impact of the inclusion of a laxative-free CTC with fecal tagging in the routine CT performed for staging of patients diagnosed with colorectal cancer and examine the technical aspects of the CTC, including quality of preparation and tolerance of patients to the examination and preparation. METHOD AND MATERIALS Thirty one c...

To evaluate the impact of the inclusion of computed tomographic colonography (CTC) involving faecal tagging and no laxatives on the computed tomography (CT) study routinely used in staging patients with colorectal cancer. CTC was performed on 25 patients who had a diagnosis of colorectal carcinoma, with pathological correlation. Researchers recorde...

A fibrino(geno)lytic nonhemorrhagic metalloproteinase (BleucMP) was purified from Bothrops leucurus snake venom by two chromatographic steps procedure on DEAE-Sephadex A-25 followed by CM-Sepharose Fast Flow column. BleucMP represented 1.75% (w/w) of the crude venom and was homogeneous on SDS-PAGE. BleucMP analyzed by MALDI TOF/TOF, showed a molecu...

Lynch syndrome (LS) is caused by inherited germline mutations in mismatch repair (MMR) genes. It is one of the commonest forms of inherited predisposition to colorectal cancer (CRC), accounting for 2-5% of all CRC. LS is characterized by early age of onset, with a tendency for multiplicity and an increased risk for extra-colonic tumors at particula...

This work describes classification, functions, location, inhibition, activation, and therapeutic applications of proteases from snake venoms and vegetables. Snake venoms and vegetables can present toxins that unchain necrosis or proteolysis due to the direct cytotoxic action of venom proteases. These proteases are potential tools in the development...

2,4-Dinitrophenol (DNP) is classically known as a mitochondrial uncoupler and, at high concentrations, is toxic to a variety of cells. However, it has recently been shown that, at subtoxic concentrations, DNP protects neurons against a variety of insults and promotes neuronal differentiation and neuritogenesis. The molecular and cellular mechanisms...

Lynch Syndrome (LS), or Hereditary non-polyposis colorectal cancer (HNPCC), is caused by inherited germline mutations in mismatch repair (MMR) genes. It is one of the commonest forms of inherited predisposition to colorectal cancer (CRC), accounting for 2%–5% of all CRC. LS is characterized by early age of onset, with a tendency for multiplicity of...

A serine protease from Bothrops alternatus snake venom was isolated using DEAE-Sephacel, Sephadex G-75 and Benzamidine-Sepharose column chromatography. The purified enzyme, named Bhalternin, ran as a single protein band on analytical polyacrylamide gel electrophoresis (SDS-PAGE) and showed molecular weights of 31,500 and 27,000 under reducing and n...

Neoadjuvant and adjuvant therapies for soft tissue sarcomas of the extremities are still controversial. The aim of this study was to analyze the results of a protocol of neoadjuvant chemoradiation therapy for extremity sarcomas. A retrospective analysis was carried out in a consecutive series of 49 adult patients with advanced extremity soft tissue...

Aggregates of the amyloid-beta peptide (Abeta) play a central role in the pathogenesis of Alzheimer's disease (AD). Identification of proteins that physiologically bind Abeta and modulate its aggregation and neurotoxicity could lead to the development of novel disease-modifying approaches in AD. By screening a phage display peptide library for high...

Aggregates of the amyloid-beta peptide (Abeta) play a central role in the pathogenesis of Alzheimer's disease (AD). Identification of proteins that physiologically bind Abeta and modulate its aggregation and neurotoxicity could lead to the development of novel disease-modifying approaches in AD. By screening a phage display peptide library for high...

Lynch syndrome represents 1-7% of all cases of colorectal cancer and is an autosomal-dominant inherited cancer predisposition syndrome caused by germline mutations in deoxyribonucleic acid (DNA) mismatch repair genes. Since the discovery of the major human genes with DNA mismatch repair function, mutations in five of them have been correlated with...

In this work, a new weakly hemorrhagic metalloproteinase (BthMP) was purified from Bothrops moojeni snake venom. This enzyme was homogeneous by native and SDS-PAGE. It showed a polypeptide chain of 23.5 kDa, pI = 7.1, and N-terminal blocked. BthMP is comprised of high proteolytic activity on casein, fibrin and bovine fibrinogen, with no coagulating...

Phospholipase A2 (PLA2, EC 3.1.1.4), a major component of snake venoms, specifically catalyzes the hydrolysis of fatty acid ester bonds at position 2 of 1,2-diacyl-sn-3-phosphoglycerides in the presence of calcium. This article reports the purification and biochemical/functional characterization of BmooTX-I, a new myotoxic acidic phospholipase A2 f...

A proteinase, named BmooMPalpha-I, from the venom of Bothrops moojeni, was purified by DEAE-Sephacel, Sephadex G-75 and heparin-agarose column chromatography. The enzyme was purified to homogeneity as judged by its migration profile in SDS-PAGE stained with coomassie blue, and showed a molecular mass of about 24.5 kDa. Its complete cDNA was obtaine...

To report the retrospective analysis of patients with locally advanced rectal cancer treated with neodjuvant radiochemotherapy. From January 1994 to December 2003, 101 patients with fixed (25%) or semi-fixed (75%) rectal adenocarcinoma were treated by preoperative radiotherapy with a dose of 45 Gy at the whole pelvis and 50.4 Gy at primary tumor, c...

Este trabalho descreve a purificação de uma enzima fibrinogenolítica da peçonha de Bothrops alternatus. A enzima, denominada BaltF, foi purificada utilizando um simples passo de cromatografia em coluna de DEAE Sephacel. A análise por eletroforese em gel de poliacrilamida com agentes desnaturantes (SDS-PAGE) mostra que essa enzima apresenta uma band...

Objectives: Anterior flap hemipelvectomy is an unusual procedure used to treat tumors from the buttock and proximal posterior thigh. This study reviews the technique and analyzes 8 such operations. Methods: Charts from 1973 to 2001 were reviewed. The technique is described and demographics, histology, symptomatology, tumor status, blood transfusion...

Hemipelvectomia utilizando retalho miocutâneo anterior é indicada para tumores extensos da região glútea e parte posterior proximal da coxa. Um paciente do sexo masculino com 49 anos apresentou-se para tratamento de tumor ulcerado e infectado com crescimento progressivo há 3 anos em região glútea esquerda, originado de uma área de ulceração e cicat...

PURPOSE: Although extended surgery has been established as an effective method for the treatment of advanced carcinoma of the colon, there are no reports in the literature of en bloc resection of the tumor together with the iliac bone. We report herein a 46-year-old woman with a second local recurrence after right colectomy, with the main objective...

Lynch syndrome represents 1-7% of all cases of colorectal cancer and is an autosomal-dominant inherited cancer predisposition syndrome caused by germline mutations in deoxyribonucleic acid (DNA) mismatch repair genes. Since the discovery of the major human genes with DNA mismatch repair function, mutations in five of them have been correlated with...