Publications by authors named "Oliva M"

Swartzia pickellii is a Leguminosae that belongs to the Caesalpinioideae sub-family the Swartzia pickellii Trypsin Inhibitor (SWTI), a serine proteinase inhibitor was isolated from its seeds. SWTI is a single polypeptide chain protein and it's structure has 174 amino acid residues, it homologous to other Kunitz plant inhibitors, however shows some major differences: it contains only one disulfide bridge, instead two which are usually found in plant Kunitz inhibitors, and the SWTI reactive site does not contain the usual Arg or Lys residues at the putative reactive site (position 65). A glycosylation site was detected at Asn38 with 1188 kDa carbohydrate portion.

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The metazoan parasite fauna of Hippoglossina macrops (n = 123) from northern Chile (30 degrees S) is quantitatively described for the first time, and the role of host age and sex was evaluated. Twelve parasite species were recovered, including 5 ectoparasites (2 Monogenea, 2 Copepoda and 1 Piscicolidae) and 7 endoparasites (1 Digenea, 3 Cestoda, 2 Acanthocephala, and 1 Nematoda). The copepod Holobomolochus chilensis, the monogenean Neoheterobothrium sp.

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Mitochondrial porin, or VDAC, is a pore-forming protein abundant in the outer mitochondrial membrane. Several publications have reported extramitochondrial localizations as well, but the evidence was considered insufficient by many, and the presence of porin in nonmitochondrial cellular compartments has remained in doubt for a long time. We have now obtained new data indicating that the plasma membrane of hematopoietic cells contains porin, probably located mostly in caveolae or caveolae-like domains.

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The effect of t-butyl hydroperoxide (t-BOOH) on the induction of the Major Histocompatibility Complex (MHC) class I genes has been studied in two cell clones (B9 and G2) of the methylcholanthrene-induced murine fibrosarcoma GR9. These two clones were selected based on their different biological and biochemical behavior specially related to their tumor induction capability when injected into a BALB/c mouse. t-BOOH (0.

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AM1, B3LYP/6-31G//AM1, and B3LYP/6-31G computational studies were performed to select the reaction pathway controlling the reactions between dimethyl acetylenedicarboxylate (DMAD) and two furanophanes, naphthalenofuranophane and anthracenofuranophane. For these domino reactions, several pathways have been characterized on the potential energy surface corresponding to two consecutive cycloadditions. The first step corresponds to a [4 + 2] intermolecular cycloaddition of DMAD with the furan ring or with the naphthalene or anthracene ring of both furanophane systems to yield an oxabicyclo[2.

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The reaction between cyclopentadiene and protonated pyridine-2-carboxaldehyde imine derivatives has been studied by using Hartree-Fock (HF) and B3LYP methods together with the 6-31G basis set. The molecular mechanism is stepwise along an inverted energy profile. This results from the protonation on both nitrogen atoms of the imine group and the pyridine framework.

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The saline extract of Bauhinia bauhinioides dry seeds was shown to inhibit cruzipain, a cysteine proteinase from Trypanosoma cruzi. The inhibitory activity was assigned to a protein with 164 amino acid residues and molecular mass of 18 034 Da that was purified by chromatography on DEAE-Sephadex, trypsin-Sepharose (removal of trypsin inhibitors), Mono Q and a reversed-phase C4 column. The primary structure is homologous to other plant Kunitz-type inhibitors, but it lacks cysteine residues and therefore the disulfide bridges.

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The in vitro antiviral activity of the essential oil from Minthostachys verticillata was investigated against herpes simplex virus type 1 (HSV-1) and pseudorabies virus (PrV). The viral inhibition was assayed employing viral plaque reduction assay. The antiviral activity of the essential oil specifically affects PrV and HSV-1 multiplication, since it was found that non toxic effects on cells were observed at the concentrations assayed.

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A serine proteinase inhibitor was purified from Delonix regia seeds a Leguminosae tree of the Caesalpinioideae subfamily. The inhibitor named DrTI, inactivated trypsin and human plasma kallikrein with K(i )values 2.19x10(-8) M and 5.

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Increasing occurrence of hemorrhagic syndrome in man, caused by contact with Lonomia obliqua caterpillars, has been reported in Southern Brazil in the past 10 years. The L. obliqua venom causes a severe consumptive coagulopathy, which can lead to hemorrhagic syndrome.

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A serine proteinase inhibitor was purified from Bauhinia bauhinioides seeds after extraction with 0.15M NaCl by ion-exchange column chromatography on DEAE-Sephadex, gel filtration on Superose 12 column, Mono Q chromatography or alternatively by affinity chromatography on trypsin- Sepharose. The inhibitor is a single polypeptide chain with molecular mass 20 kDa by gel filtration on Superose 12, but was resolved into two peaks by ion - exchange chromatography on Mono Q (FPLC system).

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The alpha2beta1 integrin is a major collagen receptor that plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Here we describe the isolation of a novel metalloproteinase/disintegrin, which is a potent inhibitor of the collagen binding to alpha2beta1 integrin. This 55-kDa protein (alternagin) and its disintegrin domain (alternagin-C) were isolated from Bothrops alternatus snake venom.

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The essential oil of the aerial parts of Baccharis notosergila was examined by GC and GC-MS. Thirty-one constituents were identified representing 96.4% and alpha-pinene, limonene, beta-caryophyllene, and spathulenol were found to be the major components.

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Enterolobium contortisiliquum trypsin inhibitor (EcTI) belongs to the Kunitz family of plant inhibitors, which are widely distributed in nature, especially in plant seeds. EcTI is composed of two polypeptide chains with a total of 174 residues, homologous to other inhibitors from the same family. EcTI crystals, which were obtained with the acupuncture-gel technique, diffract to 2.

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We have previously described Kunitz-type serine proteinase inhibitors purified from Bauhinia seeds. Human plasma kallikrein shows different susceptibility to those inhibitors. In this communication, we describe the interaction of human plasma kallikrein with fluorogenic and non-fluorogenic peptides based on the Bauhinia inhibitors' reactive site.

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The effect of two naturally occurring thiols, such as cysteine and homocysteine, has been examined for their ability to induce deoxyribose degradation and DNA damage. Copper(II) ions have been added to incubation mixtures and oxygen consumption measurements have been performed in order to correlate the observed damaging effects with the rate of metal catalyzed thiol oxidation. Ascorbic acid plus copper has been used as a positive control of deoxyribose and DNA oxidation due to reactive oxygen species.

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In photosynthetic tissues superoxide dismutase (SOD) plays an important role by scavenging the superoxide radical whose production is an usual reaction in chloroplast thylakoids. To test the differential response of SOD, two Andean potato species differing in frost resistance, Solanum curtilobum (frost resistant) and Solanum tuberosum (frost sensitive), were subjected to methyl viologen-mediated oxidative stress and polyethylene glycol (PEG)-induced water stress. A significant increment (approximately two-fold) in total SOD and FeSOD activity, which occupied about 50% of the total activity, was found when leaves of S.

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One hundred and sixty-two tumor samples were analyzed for HLA class I expression using immunohistological techniques. HLA class I total loss (phenotype no. I) was detected in 31 cases (19%), comprising 20 colorectal, 3 laryngeal, and 2 bladder carcinomas and 6 melanomas.

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We have studied the pro-antioxidant status of the rat liver on the last day of gestation and at 1, 15, and 30 days of extrauterine life. Representative variables, such as activities of superoxide dismutase (SOD), catalase, and glutathione peroxidase and concentrations of reduced glutathione and 8-hydroxy-2'-deoxyguanosine, were determined in liver to assess the degree of birth-associated oxidative stress during the fetal-neonatal transition and early development of the rat. Percentages by which liver Cu/ZnSOD activity increased over the basal value of the fetal liver were 54%, 95%, and 127% at neonatal days 1, 15, and 30, respectively.

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The effect on lung accumulation of modifying the surface compositions of (99m)Tc poly(lactide-co-glycolide) (PLGA) and (99m)Tc poly(ethylene glycol)-poly(lactide-co-glycolide) (PEG-PLGA) microspheres with different surfactants was assessed after intravenous injection into rats. Microspheres were prepared with PLGA or PEG-PLGA by the emulsion solvent evaporation method using polyvinyl alcohol (PVA), polyethylene glycol (PEG), albumin (BSA) or poloxamer 188 as surfactant, in the external aqueous phase. Commercial human albumin microspheres (Sferotec((R)), HAM) were used as reference.

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The fellodistomid Proctoeces lintoni is a common parasite of the gonads of key-hole limpets Fissurella spp. (Archaeogastropoda). It has also been found in the mantle of Octopus vulgaris and as an intestinal parasite of haemulid and gobiesocid fishes.

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Aim: To evaluate the long term results of glaucoma surgery among people in East Africa.

Methods: Participants in a population based survey of eye disease prevalence were offered glaucoma surgery using standardised criteria. Either surgical iridectomy or trabeculectomy was carried out as indicated by a medical officer or by one of two ophthalmologists.

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The deficiency of porin isoform 1 (HVDAC1) in human skeletal muscle has been associated with a pathological phenotype related to defects in the bioenergetic metabolism. In the best studied case, porin deficiency was not apparent in cultured fibroblasts: this observation raised the conclusion that no molecular defect was in the cDNA sequence coding for the protein. To get more insight in the pathogenetic mechanism that is involved in porin isoform 1 deficiency, we have determined the whole structure of the corresponding human gene.

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A serine proteinase inhibitor isolated from Leucaena leucocephala seeds (LlTI) was purified to homogeneity by acetone fractionation, ion exchange chromatography, gel filtration and reverse phase chromatography (HPLC). SDS-PAGE indicated a protein with M(r) 20000 and two polypeptide chains (alpha-chain, M(r) 15000, and beta-chain, M(r) 5000), the sequence being determined by automatic Edman degradation and by mass spectroscopy. LlTI is a 174 amino acid residue protein which shows high homology to plant Kunitz inhibitors, especially those double chain proteins purified from the Mimosoideae subfamily.

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Purpose: To determine the prevalence of glaucoma in an adult population in rural central Tanzania.

Methods: Six villages were randomly selected from eligible villages in the Kongwa district, and all residents more than 40 years of age were enumerated and invited to a comprehensive eye examination including presenting visual acuity, refraction, automated 40-point Dicon (San Diego, CA) suprathreshold screening field test, Tono-Pen (Bio-Rad, Inc., Boston, MA) intraocular pressure (IOP) measurement, and standardized examination by an ophthalmologist of anterior segment, optic nerve head, and retina after pupil dilation.

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