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1.
Sci Total Environ ; 836: 155667, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35513142

RESUMO

Soil phosphorus (P) availability may limit plant growth and alter root-soil interactions and rhizosphere microbial community composition. The composition of the rhizosphere microbial community can also be shaped by plant genotype. In this study, we examined the rhizosphere microbial communities of young plants of 24 species of eucalypts (22 Eucalyptus and two Corymbia species) under low or sufficient soil P availability. The taxonomic diversity of the rhizosphere bacterial and fungal communities was assessed by 16S and 18S rRNA gene amplicon sequencing. The taxonomic modifications in response to low P availability were evaluated by principal component analysis, and co-inertia analysis was performed to identify associations between bacterial and fungal community structures and parameters related to plant growth and nutritional status under low and sufficient soil P availability. The sequencing results showed that while both soil P availability and eucalypt species influenced the microbial community assembly, eucalypt species was the stronger determinant. However, when the plants are subjected to low P-availability, the rhizosphere selection became strongest. In response to low P, the bacterial and fungal communities in the rhizosphere of some species showed significant changes, whereas in others remained relatively constant under low and sufficient P. Co-inertia analyses revealed a significant co-dependence between plant nutrient contents and bacterial and fungal community composition only under sufficient P. By contrast, under low P, bacterial community composition was related to plant biomass production. In conclusion, our study shows that eucalypt species identity was the main factor modulating rhizosphere microbial community composition; significant shifts due to P availability were observed only for some eucalypt species.


Assuntos
Microbiota , Micobioma , Bactérias , Fungos , Microbiota/fisiologia , Fósforo , Raízes de Plantas/microbiologia , Plantas , Rizosfera , Solo/química , Microbiologia do Solo
2.
Toxicon ; 199: 87-93, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34126124

RESUMO

Snakebite accidents are a public health problem that affects the whole world, causing thousands of deaths and amputations each year. In Brazil, snakebite envenomations are caused mostly by snakes from the Bothrops genus. The local symptoms are characterized by pain, swelling, ecchymosis, and hemorrhages. Systemic disturbances can lead to necrosis and amputations. The present treatment consists of intravenous administration of bothropic antivenom, which is capable of reversing most of the systemic symptoms, while presenting limitations to treat the local effects, such as hemorrhage and to neutralize the snake venom serine protease (SVSP). In this context, we aimed to evaluate the activity of selective serine protease inhibitors (pepC and pepB) in combination with the bothropic antivenom in vivo. Further, we assessed their possible synergistic effect in the treatment of coagulopathy and hemorrhage induced by Bothrops jararaca venom. For this, we evaluated the in vivo activity in mouse models of local hemorrhage and a series of in vitro hemostasis assays. Our results showed that pepC and pepB, when combinated with the antivenom, increase its protective activity in vivo and decrease the hemostatic disturbances in vitro with high selectivity, possibly by inhibiting botropic proteases. These data suggest that the addition of serine protease inhibitor to the antivenom can improve its overall potential.


Assuntos
Bothrops , Venenos de Crotalídeos , Animais , Antivenenos/farmacologia , Antivenenos/uso terapêutico , Brasil , Venenos de Crotalídeos/toxicidade , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Camundongos , Inibidores de Serina Proteinase/farmacologia , Inibidores de Serina Proteinase/uso terapêutico
3.
AIDS Res Ther ; 5: 25, 2008 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-19102742

RESUMO

BACKGROUND: Allopathic practitioners in India are outnumbered by practitioners of traditional Indian medicine and homeopathy (TIMH), which is used by up to two-thirds of its population to help meet primary health care needs, particularly in rural areas. India has an estimated 2.5 million HIV infected persons. However, little is known about TIMH use, safety or efficacy in HIV/AIDS management in India, which has one of the largest indigenous medical systems in the world. The purpose of this review was to assess the quality of peer-reviewed, published literature on TIMH for HIV/AIDS care and treatment. RESULTS: Of 206 original articles reviewed, 21 laboratory studies, 17 clinical studies, and 6 previous reviews of the literature were identified that covered at least one system of TIMH, which includes Ayurveda, Unani medicine, Siddha medicine, homeopathy, yoga and naturopathy. Most studies examined either Ayurvedic or homeopathic treatments. Only 4 of these studies were randomized controlled trials, and only 10 were published in MEDLINE-indexed journals. Overall, the studies reported positive effects and even "cure" and reversal of HIV infection, but frequent methodological flaws call into question their internal and external validity. Common reasons for poor quality included small sample sizes, high drop-out rates, design flaws such as selection of inappropriate or weak outcome measures, flaws in statistical analysis, and reporting flaws such as lack of details on products and their standardization, poor or no description of randomization, and incomplete reporting of study results. CONCLUSION: This review exposes a broad gap between the widespread use of TIMH therapies for HIV/AIDS, and the dearth of high-quality data supporting their effectiveness and safety. In light of the suboptimal effectiveness of vaccines, barrier methods and behavior change strategies for prevention of HIV infection and the cost and side effects of antiretroviral therapy (ART) for its treatment, it is both important and urgent to develop and implement a rigorous research agenda to investigate the potential risks and benefits of TIMH and to identify its role in the management of HIV/AIDS and associated illnesses in India.

4.
Transplant Proc ; 48(1): 74-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26915846

RESUMO

BACKGROUND: Transplant renal artery stenosis (TRAS), the most common vascular complication after transplant (Tx), leads to resistant hypertension, impaired renal function, and even loss of the graft. The purpose of the study was to investigate the prevalence and factors associated with TRAS in northeastern Brazil. METHODS: The study was conducted as a retrospective case-control study in a population of Tx recipients in a renal Tx center in northeastern Brazil. Demographic and clinical characteristics of the recipients and donors, data related to the surgery, laboratory data, and number of anti-hypertensive drugs were assessed. Statistical analysis was performed with the use of SPSS 17.0. RESULTS: A total of 494 of 529 recipients were assessed, of which 24 had TRAS. The prevalence of TRAS was 4.8%. Twelve patients (50%) were men with a mean age of 46.7 ± 13.5 years. The mean time of diagnosis was 89.9 days after Tx. The risk factors associated with TRAS were number of anti-hypertensive drugs ≥2 (odds ratio, 17.0; confidence interval, 4.1 to 70.4; P = .001) and grafting with 2 or more arteries (odds ratio, 8.9; confidence interval, 1.4 to 56.6; P = .021). There was a significant reduction in mean systolic blood pressure (147.1 ± 23.7 to 127.8 ± 15.2 mm Hg, P = .001) and diastolic blood pressure (86.6 ± 13.0 to 77.6 ± 9.4 mm Hg, P = .001) after TRAS repair and in serum creatinine (2.8 ± 2.4 to 1.9 ± 1.8 mg/dL, P = .04). CONCLUSIONS: Grafts with 2 or more arteries are associated with TRAS, as well as patients who use a higher number of anti-hypertensive drugs. TRAS repair was associated with improved blood pressure control and renal function.


Assuntos
Oclusão de Enxerto Vascular/etiologia , Transplante de Rim/efeitos adversos , Obstrução da Artéria Renal/etiologia , Adulto , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Oclusão de Enxerto Vascular/epidemiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Rim/irrigação sanguínea , Rim/cirurgia , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Prevalência , Artéria Renal/fisiopatologia , Obstrução da Artéria Renal/epidemiologia , Obstrução da Artéria Renal/fisiopatologia , Insuficiência Renal/etiologia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
5.
Curr Med Chem ; 10(13): 1085-93, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12678803

RESUMO

The specific Kunitz Bauhinia ungulata factor Xa inhibitor (BuXI) and the Bauhinia variegata trypsin inhibitor (BvTI) blocked the activity of trypsin, chymotrypsin, plasmin, plasma kallikrein and factor XIIa, and factor Xa inhibition was achieved only by BuXI (K(i) 14 nM). BuXI and BvTI are highly homologous (70%). The major differences are the methionine residues at BuXI reactive site, which are involved in the inhibition, since the oxidized protein no longer inhibits factor Xa but maintains the trypsin inhibition. Quenched fluorescent substrates based on the reactive site sequence of the inhibitors were synthesized and the kinetic parameters of the hydrolysis were determined using factor Xa and trypsin. The catalytic efficiency k(cat)/K(m) 4.3 x 10(7) M(-1)sec(>-1) for Abz-VMIAALPRTMFIQ-EDDnp (lead peptide) hydrolysis by factor Xa was 10(4)-fold higher than that of Boc-Ile-Glu-Gly-Arg-AMC, widely used as factor Xa substrate. Lengthening of the substrate changed its susceptibility to factor Xa hydrolysis. Both methionine residues in the substrate influence the binding to factor Xa. Serine replacement of threonine (P(1)') decreases the catalytic efficiency by four orders of magnitude. Factor Xa did not hydrolyze the substrate containing the reactive site sequence of BvTI, that inhibits trypsin inhibitor but not factor Xa. Abz-VMIAALPRTMFIQ-EDDnp prolonged both the prothrombin time and the activated partial thromboplastin time, and the other modified substrates used in this experiment altered blood-clotting assays.


Assuntos
Bauhinia/química , Inibidores do Fator Xa , Proteínas de Plantas/metabolismo , Inibidores de Serina Proteinase/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Fator Xa/química , Corantes Fluorescentes , Humanos , Cinética , Dados de Sequência Molecular , Proteínas de Plantas/isolamento & purificação , Sementes/química , Homologia de Sequência , Inibidores de Serina Proteinase/isolamento & purificação , Especificidade por Substrato
6.
Thromb Res ; 102(5): 427-36, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11395128

RESUMO

Lonomia obliqua venom causes a severe consumptive coagulopathy, which can lead to a hemorrhagic syndrome. The crude bristles extract displays a procoagulant activity due to a Factor X and to a prothrombin activating activity. Here, we describe a 69 kDa prothrombin activator serine protease purified from L. obliqua caterpillar bristle extract using gel filtration (Sephadex G 75) and HPLC (C(4) column). The purified protein was able to activate prothrombin in a dose-dependent manner, and calcium ions increased this activity. The prothrombin-derived fluorogenic peptide (Abz-YQTFFNPRTGSQ-EDDnp) had its main cleavage site at the Arg-Thr bond. The kinetic parameters obtained for this substrate were Kmapp of 4.5 microM, kcat of 5.32 s(-1), and a kcat/Kmapp of 1.2 x 10(6) M(-1) s(-1). The prothrombin fragments generated by the purified enzyme corresponded to the molecular masses of prethrombin 2, fragment 1, fragment 2, and thrombin as seen in SDS-PAGE. The thrombin generated was able to clot purified fibrinogen. The partial amino acid sequence of the purified protein, named Lopap (L. obliqua prothrombin activator protease), showed no similarity to any known prothrombin activator.


Assuntos
Protrombina/metabolismo , Serina Endopeptidases/farmacologia , Sequência de Aminoácidos , Animais , Venenos de Artrópodes/isolamento & purificação , Venenos de Artrópodes/farmacologia , Sítios de Ligação , Testes de Coagulação Sanguínea , Cálcio/farmacologia , Relação Dose-Resposta a Droga , Fator X/metabolismo , Fibrinogênio/efeitos dos fármacos , Fibrinogênio/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Cinética , Larva , Lepidópteros , Dados de Sequência Molecular , Serina Endopeptidases/isolamento & purificação
7.
Arq Neuropsiquiatr ; 36(1): 85-9, 1978 Mar.
Artigo em Português | MEDLINE | ID: mdl-637751

RESUMO

The case of a six-year old boy's with intracranial hypertension and cranial deformities is reported. Radiological examination showed signs of intracranial hypertension and a large osteolitic area in the left posterior parietal region. Cerebral cintilography showed many abnormal captation areas. Pneumoencephalography showed deformation of the ventricular system without dilatation. Angiographic study gave images of tumoral compression by meningitic processes. Craniotomy in the osteolytic area showed an infiltrating tumoration between dura and piamater, reaching frontal, temporal and bilateral parietal areas. Histopathological examination confirmed the diagnostic of fibromixosarcoma.


Assuntos
Fibrossarcoma/patologia , Neoplasias Meníngeas/patologia , Criança , Fibrossarcoma/cirurgia , Humanos , Pressão Intracraniana , Masculino , Neoplasias Meníngeas/cirurgia , Osteólise/complicações , Crânio/patologia
8.
9.
Arq Neuropsiquiatr ; 43(2): 210-3, 1985 Jun.
Artigo em Português | MEDLINE | ID: mdl-4062607

RESUMO

Case report of Burkitt's type lymphoma with involvement of the spinal cord in a three years-old child. An epidural tumoral mass (T11-L1) was removed surgically (Fig. 2), and clinical conditions improved for a short period of time (1 and 1/2 months) after which symptoms reappeared. At this occasion a computerized tomography showed a tumoral mass occupying the spinal canal with high density at the L2 level. The patient died 6 months after the beginning of the disease. General considerations are made on Burkitt's lymphoma.


Assuntos
Linfoma de Burkitt/complicações , Compressão da Medula Espinal/etiologia , Neoplasias da Medula Espinal/complicações , Linfoma de Burkitt/diagnóstico por imagem , Linfoma de Burkitt/patologia , Pré-Escolar , Humanos , Masculino , Mielografia , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/patologia , Tomografia Computadorizada por Raios X
10.
Gac Med Mex ; 130(3): 114-8, 1994.
Artigo em Espanhol | MEDLINE | ID: mdl-7657071

RESUMO

Potential pathogenesis from pollution depends on the kind of contaminant, its concentration, its duration in environment and on host's characteristics. Faced to the threat of medical consequences of pollution, it is necessary to be alert to recognize them, with an anticipated description. Two syndromes can be distinguished, one acute and the other chronic, that may be useful as reference for an eventual epidemiologic surveillance.


Assuntos
Poluição Ambiental/prevenção & controle , Medicina Interna , Doença Aguda , Poluentes Atmosféricos/efeitos adversos , Doença Crônica , Saúde Ambiental , Poluição Ambiental/efeitos adversos , Humanos , México , Síndrome
11.
Gac Med Mex ; 128(4): 411-4, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1307990

RESUMO

The amount of neuroendocrine granules in microgranular cells of salivary glands were investigated in necropsies of 20 non-insulin dependent diabetics (NIDDM) and in 20 non-diabetic subjects with Grimelius and Fontana-Masson stainings. Granules in serous acini, and intercalated ducts were observed in both groups; however, a significant higher number of granules and microgranular cells were observed in NIDDM subjects as compared with non-diabetics. Both parotid and submaxillary glands were significantly heavier in NIDDM than in the non-diabetic group. These granules may be related to immunoreactive glucagon which has been found in submaxillary glands of rodents and might play a role in the pathogenesis of NIDDM. Further investigations should be performed to clarify whether these cells are the site of glucagon synthesis and also clarify the pathogenesis of NIDDM.


Assuntos
Grânulos Citoplasmáticos/patologia , Diabetes Mellitus Tipo 2/patologia , Glândula Parótida/patologia , Glândula Submandibular/patologia , Adulto , Idoso , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Neurossecretores/patologia , Tamanho do Órgão
12.
Braz J Med Biol Res ; 45(10): 929-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22735179

RESUMO

Lopap, found in the bristles of Lonomia obliqua caterpillar, is the first exogenous prothrombin activator that shows serine protease-like activity, independent of prothrombinase components and unique lipocalin reported to interfere with hemostasis mechanisms. To assess the action of an exogenous prothrombin activator reversing the anticoagulant and antihemostatic effect induced by low molecular weight heparin (LMWH), male New Zealand rabbits (N = 20, weighing 3.8-4.0 kg) allocated to 4 groups were anticoagulated with 1800 IU/kg LMWH (iv) over 2 min, followed by iv administration of saline (SG) or recombinant Lopap (rLopap) at 1 µg/kg (LG1) or 10 µg/kg (LG10), 10 min after the injection of LMWH, in a blind manner. Control animals (CG) were treated only with saline. The action of rLopap was assessed in terms of activated partial thromboplastin time (aPTT), prothrombin fragment F1+2, fibrinogen, and ear puncture bleeding time (BT) at 5, 10, 15, 17, 20, 30, 40, 60, and 90 min after initiation of LMWH infusion. LG10 animals showed a decrease of aPTT in more than 50% and BT near to normal baseline. The level of prothrombin fragment F1+2 measured by ELISA had a 6-fold increase with rLopap treatment (10 µg/kg) and was inversely proportional to BT in LMWH-treated animals. Thus, Lopap, obtained in recombinant form using E. coli expression system, was useful in antagonizing the effect of LMWH through direct prothrombin activation, which can be a possible strategy for the reversal of bleeding and anticoagulant events.


Assuntos
Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Hemorragia/tratamento farmacológico , Antagonistas de Heparina/farmacologia , Heparina de Baixo Peso Molecular/antagonistas & inibidores , Protrombina/efeitos dos fármacos , Serina Endopeptidases/farmacologia , Animais , Hemorragia/induzido quimicamente , Masculino , Coelhos
13.
Sci Total Environ ; 408(22): 5381-91, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20716461

RESUMO

Studies on mycorrhizal symbiosis effects on metal accumulation and plant tolerance are not common in perennial crops under metal stress. The objective of this study was to evaluate the influence of mycorrhization on coffee seedlings under Cu and Zn stress. Copper (Cu) and zinc (Zn) uptake and some biochemical and physiological traits were studied in thirty-week old Coffea arabica seedlings, in response to the inoculation with arbuscular mycorrhizal fungi (AMF) and to increasing concentrations of Cu or Zn in soil. The experiments were conducted under greenhouse conditions in a 2×4 factorial design (inoculation or not with AMF and 0, 50, 150 and 450mgkg(-1) Cu or 0, 100, 300 and 900mgkg(-1) Zn). Non-mycorrhizal plants maintained a hampered and slow growth even in a soil with appropriate phosphorus (P) levels for this crop. As metal levels increased in soil, a greater proportion of the total absorbed metals were retained by roots. Foliar Cu concentrations increased only in non-mycorrhizal plants, reaching a maximum concentration of 30mgkg(-1) at the highest Cu in soil. Mycorrhization prevented the accumulation of Cu in leaves, and mycorrhizal plants showed higher Cu contents in stems, which indicated a differential Cu distribution in AMF-associated or non-associated plants. Zn distribution and concentrations in different plant organs followed a similar pattern independently of mycorrhization. In mycorrhizal plants, only the highest metal concentrations caused a reduction in biomass, leading to significant changes in some biochemical indicators, such as malondialdehyde, proline and amino acid contents in leaves and also in foliar free amino acid composition. Marked differences in these physiological traits were also found due to mycorrhization. In conclusion, AMF protected coffee seedlings against metal toxicity.


Assuntos
Coffea/metabolismo , Cobre/metabolismo , Micorrizas/metabolismo , Poluentes do Solo/metabolismo , Simbiose , Zinco/metabolismo , Aminoácidos/metabolismo , Coffea/efeitos dos fármacos , Coffea/microbiologia , Cobre/toxicidade , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Produtos Agrícolas/microbiologia , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Poluentes do Solo/toxicidade , Estresse Fisiológico , Zinco/toxicidade
15.
Arq. bras. med. vet. zootec ; 65(4): 1231-1238, Aug. 2013. graf, tab
Artigo em Português | LILACS | ID: lil-684484

RESUMO

O uso do soro lácteo como complemento na formulação de alimentos visando ao seu aproveitamento é uma alternativa para a obtenção de novos produtos. Neste trabalho, desenvolveram-se bebidas à base de soro oriundo de queijo coalho tipo A com frutas e hortaliças. Na formulação das bebidas, utilizaram-se diferentes proporções entre soro lácteo, frutas e hortaliças, com adição de 10% de açúcar. Seis bebidas foram formuladas e submetidas a um teste de preferência, e as três primeiras colocadas foram submetidas a um teste de aceitação sensorial. As três preferidas foram as bebidas sabor graviola, morango e goiaba. A bebida sabor graviola obteve aceitação com as melhores notas nos atributos sensoriais cor, sabor, aparência e qualidade global, seguida pela formulação de sabor morango, mas sem diferença significativa (P>0,05). A bebida sabor goiaba teve o diferencial no atributo odor e superou as bebidas sabor graviola e morango (P<0,05). Conclui-se que é viável a elaboração de bebidas à base de soro de queijo coalho com frutas.


The use of whey as complement in food formulation aiming it's an alternative for the attainment of new products. The aim of this work was developed a type A curd cheese whey derived drink with fruits and vegetables. On drink's formulation was used different ratios of whey, fruits and vegetables, with 10% of sugar. Six drinks were formulated and submited to a preference test. The three best drinks were submitted to a acceptance test. The three best drinks were graviola, strawberry and guava flavours. The graviola one had the greater acceptability with best grades in color's sensory attributes, flavor, appearance and overall quality, following the strawberry flavor, but without significant difference (P<0,05). The guava dink had it's differential on scent character, overcoming the graviola and strawberry drinks (P<0,05). In conclusion we can say that whey-based drink with fruits is viable.


Assuntos
Animais , Alimentos/classificação , Bebidas/análise , Frutas , Queijo , Verduras , Daucus carota , Mentha
16.
Braz. j. med. biol. res ; 45(10): 929-934, Oct. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-647751

RESUMO

Lopap, found in the bristles of Lonomia obliqua caterpillar, is the first exogenous prothrombin activator that shows serine protease-like activity, independent of prothrombinase components and unique lipocalin reported to interfere with hemostasis mechanisms. To assess the action of an exogenous prothrombin activator reversing the anticoagulant and antihemostatic effect induced by low molecular weight heparin (LMWH), male New Zealand rabbits (N = 20, weighing 3.8-4.0 kg) allocated to 4 groups were anticoagulated with 1800 IU/kg LMWH (iv) over 2 min, followed by iv administration of saline (SG) or recombinant Lopap (rLopap) at 1 µg/kg (LG1) or 10 µg/kg (LG10), 10 min after the injection of LMWH, in a blind manner. Control animals (CG) were treated only with saline. The action of rLopap was assessed in terms of activated partial thromboplastin time (aPTT), prothrombin fragment F1+2, fibrinogen, and ear puncture bleeding time (BT) at 5, 10, 15, 17, 20, 30, 40, 60, and 90 min after initiation of LMWH infusion. LG10 animals showed a decrease of aPTT in more than 50% and BT near to normal baseline. The level of prothrombin fragment F1+2 measured by ELISA had a 6-fold increase with rLopap treatment (10 µg/kg) and was inversely proportional to BT in LMWH-treated animals. Thus, Lopap, obtained in recombinant form using E. coli expression system, was useful in antagonizing the effect of LMWH through direct prothrombin activation, which can be a possible strategy for the reversal of bleeding and anticoagulant events.


Assuntos
Animais , Masculino , Coelhos , Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Hemorragia/tratamento farmacológico , Antagonistas de Heparina/farmacologia , Heparina de Baixo Peso Molecular/antagonistas & inibidores , Protrombina/efeitos dos fármacos , Serina Endopeptidases/farmacologia , Hemorragia/induzido quimicamente
17.
Acta Crystallogr D Biol Crystallogr ; 60(Pt 6): 1112-4, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15159572

RESUMO

SMase I, a 32 kDa sphingomyelinase found in Loxosceles laeta venom, is responsible for the major pathological effects of spider envenomation. This toxin has been cloned and functionally expressed as a fusion protein containing a 6 x His tag at its N-terminus to yield a 33 kDa protein [Fernandes-Pedrosa et al. (2002), Biochem. Biophys. Res. Commun. 298, 638-645]. The recombinant protein possesses all the biological properties ascribed to the whole L. laeta venom, including dermonecrotic and complement-dependent haemolytic activities. Dynamic light-scattering experiments conducted at 291 K demonstrate that the sample possesses a monomodal distribution, with a hydrodynamic radius of 3.57 nm. L. laeta SMase I was crystallized by the hanging-drop vapour-diffusion technique using the sparse-matrix method. Single crystals were obtained using a buffer solution consisting of 0.08 M HEPES and 0.9 M trisodium citrate, which was titrated to pH 7.5 using 0.25 M sodium hydroxide. Complete three-dimensional diffraction data were collected to 1.8 angstroms at the Laboratório Nacional de Luz Síncrotron (LNLS, Campinas, Brazil). The crystals belong to the hexagonal system (space group P6(1) or P6(5)), with unit-cell parameters a = b = 140.6, c = 113.6 angstroms. A search for heavy-atom derivatives has been initiated and elucidation of the crystal structure is currently in progress.


Assuntos
Esfingomielina Fosfodiesterase/química , Venenos de Aranha/química , Animais , Citratos/farmacologia , Cristalografia por Raios X , DNA Complementar/metabolismo , Luz , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Espalhamento de Radiação , Citrato de Sódio , Aranhas , Temperatura
18.
Immunopharmacology ; 45(1-3): 145-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10615004

RESUMO

Kunitz type Bauhinia ungulata factor Xa inhibitor (BuXI) was purified from B. ungulata seeds. BuXI inactivates factor Xa and human plasma kallikrein (HuPK) with Ki values of 18.4 and 6.9 nM, respectively. However, Bauhinia variegata trypsin inhibitor (BvTI) which is 70% homologous to BuXI does not inhibit factor Xa and is less efficient on HuPK (Ki = 80 nM). The comparison between BuXI and BvTI reactive site structure indicates differences at Met59, Thr66 and Met67 residues. The hydrolysis rate of quenched fluorescence peptide substrates based on BuXI reactive site sequence, Abz-VMIAALPRTMFIQ-EDDnp (leading peptide), by HuPK and porcine pancreatic kallikrein (PoPK) is low, but hydrolysis is enhanced with Abz-VMIAALPRTMQ-EDDnp, derived from the leading peptide shortened by removing the dipeptide Phe-Ileu from the C-terminal portion, for HuPK (Km = 0.68 microM, k(cat)/Km = 1.3 x 10(6) M(-1) s(-1)), and the shorter substrate Abz-LPRTMQ-EDDnp is better for PoPK (Km = 0.66 microM, k(cat)/Km = 2.2 x 10(3) M(-1) s(-1)). The contribution of substrate methionine residues to HuPK and PoPK hydrolysis differs from that observed with factor Xa. The determined Km and k(cat) values suggest that the substrates interact with kallikreins the same as an enzyme and inhibitor interacts to form complexes.


Assuntos
Fabaceae/química , Inibidores do Fator Xa , Calicreínas/sangue , Calicreínas/metabolismo , Proteínas de Plantas/isolamento & purificação , Plantas Medicinais , Calicreínas Teciduais/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Fator Xa/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Sementes/enzimologia , Sementes/metabolismo , Inibidores de Serina Proteinase/metabolismo , Especificidade por Substrato
19.
Biol Chem ; 382(1): 109-13, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11258660

RESUMO

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. The hydrolysis of the substrate based on the B. variegata inhibitor reactive site sequence, Abz-VVISALPRSVFIQ-EDDnp (Km 1.42 microM, kcat 0.06 s(-1), and kcat/Km 4.23 x 10(4) M(-1) s(-1)), is more favorable than that of Abz-VMIAALPRTMFIQ-EDDnp, related to the B. ungulata sequence (Km 0.43 microM, kcat 0.00017 s(-1), and kcat/Km 3.9 x 10(2) M(-1) s(-1)). Human plasma kallikrein does not hydrolyze the substrates Abz-RPGLPVRFESPL-EDDnp and Abz-FESPLRINIIKE-EDDnp based on the B. bauhinioides inhibitor reactive site sequence, the most effective inhibitor of the enzyme. These peptides are competitive inhibitors with Ki values in the nM range. The synthetic peptide containing 19 amino acids based on the B. bauhinioides inhibitor reactive site (RPGLPVRFESPL) is poorly cleaved by kallikrein. The given substrates are highly specific for trypsin and chymotrypsin hydrolysis. Other serine proteinases such as factor Xa, factor XII, thrombin and plasmin do not hydrolyze B. bauhinioides inhibitor related substrates.


Assuntos
Corantes Fluorescentes/farmacologia , Calicreínas/metabolismo , Peptídeos/farmacologia , Plantas/química , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Sequência de Aminoácidos , Animais , Sítios de Ligação/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Humanos , Hidrólise , Calicreínas/efeitos dos fármacos , Dados de Sequência Molecular , Peptídeos/síntese química , Suínos , Inibidor da Tripsina de Soja de Kunitz/isolamento & purificação
20.
Arq. bras. med. vet. zootec ; 58(3): 427-431, jun. 2006. tab
Artigo em Português | LILACS | ID: lil-443599

RESUMO

Realizaram-se avaliações bacteriológicas da matéria-prima utilizada na elaboração de um produto cárneo caprino tipo hambúrguer defumado, antes e após sanitização. A carne foi tratada por aspersão, com uma solução de ácidos orgânicos contendo 2 por cento de ácido acético, 1 por cento de ácido lático, 0,25 por cento de ácido cítrico e 0,1 por cento de ácido ascórbico, e armazenada sob refrigeração. As análises bacteriológicas foram realizadas no dia 0 e aos 7 e 14 dias após defumação. Na carne, no dia 0, a contagem de coliformes fecais estava acima do limite permitido pela legislação vigente, mas sete dias após a sanitização, esse parâmetro estava dentro dos limites permitidos. No produto final todos os parâmetros bacteriológicos encontraram-se dentro dos padrões higiênico-sanitários.


In order to obtain a safe goat smoked hamburger, bacteriological analysis of the raw material was performed before and after sanitation. Meat was sprayed with a solution of organic acids containing 2 percent acetic acid, 1 percent lactic acid, 0.25 percent citric acid and 0.1 percent ascorbic acid and, after that, stored under refrigeration. Bacteriological analysis was carried out on days 0, 7 and 14 after goat smoked hamburger processing. In meat, on day 0, the fecal coliform count was above legal limits, but on day 7 after sanitation this parameter was these limits. In the final product, all the results of the bacteriological parameters were according to the sanitary-hygienic standards.


Assuntos
Técnicas Bacteriológicas , Carne/análise , Cabras
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