Sequesterpene Lactones Isolated from a Brazilian Cerrado Plant ( spp. as Anti-Proliferative Compounds, Characterized by Functional and Proteomic Analysis, are Candidates for New Therapeutics in Glioblastoma.

Gliomas are responsible for more than 60% of all primary brain tumors. Glioblastoma multiforme (GBM), a grade IV tumor (WHO), is one of the most frequent and malignant gliomas. Despite two decades of advances in the discovery of new markers for GBM, the chemotherapy of choice falls to temozolomide after surgery and radiotherapy, which are not enough to increase the survival of patients to more than 15 months.

Trypanosoma cruzi: analysis of two different strains after piplartine treatment.

The hemoflagellate protozoan, Trypanosoma cruzi, mainly transmitted by triatomine insects through blood transfusion or from mother-to-child, causes Chagas' disease. This is a serious parasitic disease that occurs in Latin America, with considerable social and economic impact. Nifurtimox and benznidazole, drugs indicated for treating infected persons, are effective in the acute phase, but poorly effective during the chronic phase.

A brain proteome profile in rats exposed to methylmercury or thimerosal (ethylmercury).

Exposure to organomercurials has been associated with harmful effects on the central nervous system (CNS). However, the mechanisms underlying organomercurial-mediated neurotoxic effects need to be elucidated. Exposure to toxic elements may promote cellular modifications such as alterations in protein synthesis in an attempt to protect tissues and organs from damage.

PROTEINS OF THE INTEGUMENTARY SYSTEM OF THE HONEYBEE, Apis mellifera.

The integument of insects and other arthropods is composed of an inner basal lamina coated by the epidermis, which secretes the bulk of the outer integument layer, the cuticle. The genome sequencing of several insect species has allowed predicting classes of proteins integrating the cuticle. However, only a small proportion of them, as well as other proteins in the integumentary system, have been validated.

Peptide Characterization of Mature Fluorotic and Control Human Enamel.

Exposure to high fluoride levels during amelogenesis causes enamel fluorosis. This study aimed to determine and compare the amino acid sequences in the enamel of fluorotic and control teeth. This investigation included enamel samples obtained from erupted and non-erupted third molars with either TF grade 4-6 (n=7) fluorosis or no sign of fluorosis (controls, n=7).

rBaltMIP, a recombinant alpha-type myotoxin inhibitor from Bothrops alternatus (Rhinocerophis alternatus) snake, as a potential candidate to complement the antivenom therapy.

Phospholipase A 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 A inhibitor from Bothrops alternatus (Rhinocerophis alternatus) snake in its recombinant form (rBaltMIP) to complement the conventional antivenom therapy. Biochemical experiments showed that rBaltMIP presented pI 5.

Gender-specific effects of intrauterine growth restriction on the adipose tissue of adult rats: a proteomic approach.

Background: Intrauterine growth restriction (IUGR) may program metabolic alterations affecting physiological functions and lead to diseases in later life. The adipose tissue is an important organ influencing energy homeostasis. The present study was aimed at exploring the consequences of IUGR on the retroperitoneal adipose tissue of adult male and female rats, using a proteomic approach.

Moojenactivase, a novel pro-coagulant PIIId metalloprotease isolated from Bothrops moojeni snake venom, activates coagulation factors II and X and induces tissue factor up-regulation in leukocytes.

Coagulopathies following snakebite are triggered by pro-coagulant venom toxins, in which metalloproteases play a major role in envenomation-induced coagulation disorders by acting on coagulation cascade, platelet function and fibrinolysis. Considering this relevance, here we describe the isolation and biochemical characterization of moojenactivase (MooA), a metalloprotease from Bothrops moojeni snake venom, and investigate its involvement in hemostasis in vitro. MooA is a glycoprotein of 85,746.

Application of 2D BN/SDS-PAGE coupled with mass spectrometry for identification of VDAC-associated protein complexes related to mitochondrial binding sites for type I brain hexokinase.

Two types of binding sites for hexokinase, designated as Type A or Type B sites, have been shown to coexist on brain mitochondria. The ratio of these sites varies between species. HK1 attaches by reversibly binding to the voltage dependent anion channel (VDAC).

Production and diagnostic application of recombinant domain III of West Nile envelope protein in Brazil.

Introduction: West Nile virus (WNV) is a flavivirus with a natural cycle involving mosquitoes and birds. Over the last 11 years, WNV has spread throughout the Americas with the imminent risk of its introduction in Brazil.

Methods: Envelope protein domain III of WNV (rDIII) was bacterially expressed and purified.

Changes in the expression of proteins associated with aerobic glycolysis and cell migration are involved in tumorigenic ability of two glioma cell lines.

Background: The most frequent and malignant brain cancer is glioblastoma multiforme (GBM). In gliomas, tumor progression and poor prognosis are associated with the tumorigenic ability of the cells. U87MG cells (wild-type p53) are known to be tumorigenic in nude mice, but T98G cells (mutant p53) are not tumorigenic.

Quantitative proteomic analysis and functional studies reveal that nucleophosmin is involved in cell death in glioblastoma cell line transfected with siRNA.

Previously, we reported that nucleophosmin (NPM) was increased in glioblastoma multiforme (GBM). NPM is a phosphoprotein related to apoptosis, ribosome biogenesis, mitosis, and DNA repair, but details about its function remain unclear. We treated U87MG and A172 cells with small interference RNA (siRNA) and obtained a reduction of 80% in NPM1 expression.

Recovery and identification of mature enamel proteins in ancient teeth.

Proteins in mineralized tissues provide a window to the past, and dental enamel is peculiar in being highly resistant to diagenesis and providing information on a very narrow window of time, such as the developing period; however, to date, complete proteins have not been extracted successfully from ancient teeth. In this work we tested the ability of a whole-crown micro-etch technique to obtain enamel protein samples from mature enamel of recently extracted (n = 2) and ancient (n = 2; ad 800 to 1100) third molars. Samples were analyzed using matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry, and the resulting spectra were searched against the Swiss-Prot protein database using the Mascot software for protein identification.

Expression of human protein S100A7 (psoriasin), preparation of antibody and application to human larynx squamous cell carcinoma.

Background: Up-regulation of S100A7 (Psoriasin), a small calcium-binding protein, is associated with the development of several types of carcinomas, but its function and possibility to serve as a diagnostic or prognostic marker have not been fully defined. In order to prepare antibodies to the protein for immunohistochemical studies we produced the recombinant S100A7 protein in E. coli.

New insights into trypanosomatid U5 small nuclear ribonucleoproteins.

Several protozoan parasites exist in the Trypanosomatidae family, including various agents of human diseases. Multiple lines of evidence suggest that important differences are present between the translational and mRNA processing (trans splicing) systems of trypanosomatids and other eukaryotes. In this context, certain small complexes of RNA and protein, which are named small nuclear ribonucleoproteins (U snRNPs), have an essential role in pre-mRNA processing, mainly during splicing.

Inhibition of neutrophil migration by hemopexin leads to increased mortality due to sepsis in mice.

Rationale: The reduction of neutrophil migration to the bacterial focus is associated with poor outcome in sepsis.

Objectives: The objective of this study was to identify soluble substances in the blood of septic mice that inhibit neutrophil migration.

Methods: A pool of serum obtained from mice 2 hours after the induction of severe sepsis by cecal ligation and puncture inhibited the neutrophil migration.

Proteomic analysis of total cellular proteins of human neutrophils.

Background: Neutrophils are the most abundant leukocytes in peripheral blood and represent one of the most important elements of innate immunity. Recent subcellular proteomic studies have focused on the identification of human neutrophil proteins in various subcellular membrane and granular fractions. Although there are relatively few studies dealing with the analysis of the total extract of human neutrophils, many biological problems such as the role of chemokines, adhesion molecules, and other activating inputs involved in neutrophil responses and signaling can be approached on the basis of the identification of the total cellular proteins.

Adaptive shifts in osmoregulatory strategy and the invasion of freshwater by brachyuran crabs: evidence from Dilocarcinus pagei (Trichodactylidae).

To evaluate putative adaptive changes underpinning the invasion of freshwater by the Brachyura, this investigation examines anisosmotic extra and isosmotic intracellular osmoregulatory capabilities in Dilocarcinus pagei, a neotropical, hololimnetic crab, including its embryonic and juvenile phases. All ontogenetic stages show a remarkable ability to survive a high salinity medium (25 per thousand, 750 mOsm/kg H2O, 350 mm Na+, 400 mM Cl-). Adults hyper-regulate hemolymph osmolality up to isosmoticity at 744 mOsm kg/H2O (24 per thousand), [Na+] and [Cl-] becoming isoionic at 449 (22 per thousand) and 256 mM (16 per thousand), respectively.

Comparison of three methods for enamel protein extraction in different developmental phases of rat lower incisors.

Protein extraction methods [urea, trichloroacetic acid (TCA), and acetic acid] were compared for protein recovery from rat incisor developing enamel in the S phase (intermediate/late secretion), M1 phase (early maturation), M2 phase (intermediate maturation), and M3 phase (final maturation). We compared the protein recoveries with the percentage of enamel matrix dry weight burnt off by incineration. Our results indicate that TCA and urea were equally efficient for the extraction of S-stage proteins (85% and 90% recovery, respectively), while urea was the best for M1-stage proteins (92% recovery), and TCA the best for M2-stage (99% recovery) and M3-stage (60% recovery) proteins.

Low molecular weight squash trypsin inhibitors from Sechium edule seeds.

Nine chromatographic components containing trypsin inhibitor activity were isolated from Sechium edule seeds by acetone fractionation, gel filtration, affinity chromatography and RP-HPLC in an overall yield of 46% of activity and 0.05% of protein. The components obtained with highest yield of total activity and highest specific activity were sequenced by Edman degradation and their molecular masses determined by mass spectrometry.

Determination and reoxidation of the disulfide bridges of a squash-type trypsin inhibitor from Sechium edule seeds.

The determination of the disulfide pairings of SETI-II, a trypsin inhibitor isolated from Sechium edule, is described herein. The inhibitor contains 31 amino acid residues per mol, 6 of which are cysteine. Forty-five nmol (160 microg) of SETI-II was hydrolyzed with 20 microg thermolysin for 48 hr at 45 degrees C, and peptides were separated by reverse phase high performance liquid chromatography (RP-HPLC).

Amino acid sequence and tertiary structure of Cratylia mollis seed lectin.

Carbohydrate-protein interactions play a key role in many biological processes. Cramoll is a lectin purified from Cratylia mollis seeds that is taxonomically related to concanavalin A (Con A). Although Cramoll and Con A have the same monosaccharide specificity, they have different glycoprotein binding profiles.

Fluorescence properties of tryptophan residues in the monomeric d-chain of Glossoscolex paulistus hemoglobin: an interpretation based on a comparative molecular model.

The primary structure of the 142 residue Glossoscolex paulistus d-chain hemoglobin has been determined from Edman degradation data of 11 endo-Glu-C peptides and 11 endo-Lys-C peptides, plus the results of Edman degradation of the intact globin. Tryptophan occupies positions 15, 33 and 129. Homology modeling allowed us to assign the positions of these Trp residues relative to the heme and its environment.