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1.
Med Mycol ; 58(2): 227-239, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31095342

RESUMO

Current antifungal drugs present poor effectiveness and there is no available vaccine for fungal infections. Thus, novel strategies to treat or prevent invasive mycosis, such as cryptococcosis, are highly desirable. One strategy is the use of immunomodulators of polysaccharide nature isolated from mushrooms. The purpose of the present work was to evaluate the immunostimulatory activity of ß-(1,3)-glucan-containing exopolysaccharides (EPS) from the edible mushrooms Auricularia auricula in phagocytes and mice infected with Cryptococcus neoformans. EPS triggered macrophages and dendritic cell activation upon binding to Dectin-1, a pattern recognition receptor of the C-type lectin receptor family. Engagement of Dectin-1 culminated in pro-inflammatory cytokine production and cell maturation via its canonical Syk-dependent pathway signaling. Furthermore, upon EPS treatment, M2-like phenotype macrophages, known to support intracellular survival and replication of C. neoformans, repolarize to M1 macrophage pattern associated with enhanced production of the microbicidal molecule nitric oxide that results in efficient killing of C. neoformans. Treatment with EPS also upregulated transcript levels of genes encoding products associated with host protection against C. neoformans and Dectin-1 mediated signaling in macrophages. Finally, orally administrated ß-glucan-containing EPS from A. auricular enhanced the survival of mice infected with C. neoformans. In conclusion, the results demonstrate that EPS from A. auricula exert immunostimulatory activity in phagocytes and induce host protection against C. neoformans, suggesting that polysaccharides from this mushroom may be promising as an adjuvant for vaccines or antifungal therapy.


Assuntos
Agaricales/química , Criptococose/prevenção & controle , Polissacarídeos Fúngicos/imunologia , Fagócitos/efeitos dos fármacos , Fagócitos/imunologia , beta-Glucanas/imunologia , Animais , Criptococose/imunologia , Cryptococcus neoformans/imunologia , Citocinas/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Fatores Imunológicos/farmacologia , Lectinas Tipo C/imunologia , Pneumopatias Fúngicas , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Fagócitos/microbiologia , Transdução de Sinais , beta-Glucanas/farmacologia
2.
J Helminthol ; 90(3): 377-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26096177

RESUMO

Haemonchus contortus is one of the major gastrointestinal nematodes responsible for significant economic and production losses of sheep. Diseases caused by this species lack effective anthelmintic products, and the search for new compounds to replace synthetic anthelmintics has been extensive. The present investigation assesses the in vitro activity of the essential oil of melaleuca (Melaleuca alternifolia), both free (TTO) and nanostructured (nanoTTO), and terpinen-4-ol (terp-4-ol) on eggs and larvae of H. contortus. Tests of egg hatching (EHT) and inhibition of larval migration (LMIT) were used to assess the in vitro efficacy of TTO, nanoTTO and terp-4-ol. Using EHT, at a concentration of 3.5 mg/ml, 100% inhibition occurred using TTO and terp-4-ol, with LC50 values of 0.43 and 0.63 mg/ml, and LC90 values of 1.75 mg/ml and 3.12 mg/ml, respectively. NanoTTO had lower activity, with 82.6% inhibition at the same concentration. Using LMIT, TTO and nanoTTO had a similar activity with 88.0% and 84.8% inhibition, respectively, at a concentration of 56 mg/ml. Terp-4-ol had a greater effect on larvae, with 85.7% inhibition at a concentration of 56 mg/ml and 82.4% at 3.5 mg/ml, demonstrating high activity at the lowest concentration tested. Therefore, the results indicate that all substances tested showed ovicidal and larvicidal activity against H. contortus. TTO, terp-4-ol and, mainly, nanoTTO may be targeted in in vivo studies, besides being a promising line of research into the control and treatment of veterinary important helminths.


Assuntos
Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Melaleuca/química , Óleos Voláteis/farmacologia , Terpenos/farmacologia , Zigoto/efeitos dos fármacos , Animais , Anti-Helmínticos/isolamento & purificação , Bioensaio , Haemonchus/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Óleos Voláteis/isolamento & purificação , Análise de Sobrevida , Terpenos/isolamento & purificação
3.
Hum Reprod ; 29(11): 2439-45, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25240012

RESUMO

STUDY QUESTION: Is the pain associated with levonorgestrel-releasing intrauterine system (LNG-IUS) insertion reduced by intracervical anesthesia in women without previous vaginal birth? SUMMARY ANSWER: Intracervical anesthesia was not associated with reduced pain in women without previous vaginal birth. WHAT IS KNOWN ALREADY: The pain associated with the insertion of intrauterine contraceptives (IUCs) is a limiting factor for the use of these contraceptives by some women. No prophylactic pharmacological intervention has proven efficacy in relieving pain during or after the insertion of IUCs. However, previous studies included women with previous vaginal delivery, and injectable intracervical anesthesia was not evaluated in any of these studies. STUDY DESIGN, SIZE, DURATION: This was a randomized, open, parallel-group clinical trial that evaluated 100 women without previous vaginal delivery who wished to use the LNG-IUS for the first time. These women were evaluated immediately after LNG-IUS insertion and then 2 h and 6 h later. PARTICIPANTS/MATERIALS, SETTING, METHODS: The 100 women were randomized into two groups: (i) use of a non-steroidal anti-inflammatory drug (NSAID) (ibuprofen, 400 mg) 1 h prior to LNG-IUS insertion; or (ii) 2% lidocaine intracervical injection 5 min prior to LNG-IUS insertion. The women were evaluated immediately after LNG-IUS insertion and then 2 h and 6 h after insertion. Two pain scales were used (the visual analogue scale and the facial pain scale) in addition to assessing the ease of insertion (as rated by the provider) and the level of discomfort during the procedure (as rated by the patient). Multivariate logistic regression was performed to analyze the predictors associated with moderate/severe pain. MAIN RESULTS AND THE ROLE OF CHANCE: The pain and discomfort associated with LNG-IUS insertion, and the ease of insertion of the LNG-IUS did not differ between the groups. Nulliparity was more associated with moderate/severe pain [adjusted odds ratio (OR): 3.1 (95% confidence interval (CI): 1.3-7.80]. Injectable intracervical anesthesia use reduced the risk of moderate/severe pain by 40% [adjusted OR: 0.6 (95% CI: 0.2-1.4)]. The difference between the mean pain score in the intracervical anesthesia group and the NSAID group was <10%; thus, the effect size of the intervention was not significant. LIMITATIONS, REASONS FOR CAUTION: Intracervical anesthesia was compared with an oral medication in this study. Intracervical injection of a saline solution or even a dry needling as the placebo for a double-blind study could be a more adequate control; however, this approach was not a protocol approved by the institutional review board. Considering that the majority of the insertions were easy (>80% in both groups), the results may not be extrapolated to difficult insertions with moderate/severe pain where local anesthesia may have a role. WIDER IMPLICATIONS OF THE FINDINGS: The findings can be generalized to most insertions in nulliparous women or in those without a previous vaginal delivery. There is currently no evidence to recommend the routine use of prophylactic intracervical anesthesia prior to LNG-IUS insertion; there is no evidence that this treatment reduces insertion-related pain. STUDY FUNDING/COMPETING INTERESTS: RAF and CSV give occasional lectures for Bayer Healthcare. This study received funding from the National Institute of Hormones and Women's Health, National Council for Scientific and Technological Development (CNPq). TRIAL REGISTRATION NUMBER: NCT02155166.


Assuntos
Anestésicos Locais/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Colo do Útero/efeitos dos fármacos , Dispositivos Intrauterinos Medicados/efeitos adversos , Lidocaína/uso terapêutico , Dor/tratamento farmacológico , Adulto , Anestésicos Locais/administração & dosagem , Feminino , Humanos , Levanogestrel/administração & dosagem , Lidocaína/administração & dosagem , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Resultado do Tratamento
4.
Zygote ; 22(4): 496-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24040895

RESUMO

We aimed in this study to assess whether serum-decreased bovine cumulus-oocyte complex (COC) steroidogenesis during in vitro maturation (IVM) is caused by deficient androgen milieu. For this approach, bovine COCs were cultured in serum-supplemented IVM medium in the presence or absence of 1 µM androstenedione. After 24 h of culture, medium was collected and analyzed for its content of estradiol-17ß (E2) and progesterone (P4). Medium E2 content markedly increased after incubation of COCs with androstenedione (17.52 ± 1.86 ng/ml to the androgen group; 0.32 ± 0.05 ng/ml to the non-androgen group). No significant difference in the P4 content was detected despite the presence of androstenedione (21.83 ± 1.61 ng/ml to the androgen group; 21.73 ± 1.67 ng/ml to the non-androgen group). Our data provide compelling evidence that bovine COCs steroidogenesis remains functional during culture in serum-supplemented medium and suggest that serum-induced decreased COCs estradiol secretion is caused by deficiency of an aromatizable androgen source.


Assuntos
Androstenodiona/farmacologia , Estradiol/metabolismo , Oócitos/metabolismo , Soro , Animais , Bovinos , Células Cultivadas , Meios de Cultura/química , Meios de Cultura/farmacologia , Estradiol/biossíntese , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/efeitos dos fármacos , Folículo Ovariano , Progesterona/metabolismo
5.
Genet Mol Res ; 13(4): 9795-805, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25501189

RESUMO

Drought and rice blast disease caused by Magnaporthe oryzae are two of the most serious threats to global rice production. To explore the mechanisms underlying gene expression induced in rice by stresses, studies involving transcriptome analyses have been conducted over the past few years. Thus, it is crucial to have a reliable set of reference genes to normalize the expression levels of rice genes affected by different stresses. To identify potential reference genes for studies of the differential expression of target genes in rice under M. oryzae infection and drought conditions, the present study evaluated five housekeeping genes for the normalization of gene expression. The stability of the expression of these genes was assessed using the analytical software packages geNorm and NormFinder. For all samples analyzed, the stability rank was UBQ5 > GAPDH > eIF-4α> ß-TUB > 18S rRNA. The data showed that the UBQ5, GAPDH, and eIF-4αgenes are appropriate, high-performing reference genes and will be highly useful in future expression studies of fungal infections and drought in rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes Essenciais , Genes de Plantas , Oryza/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Secas , Fator de Iniciação 4A em Eucariotos/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Magnaporthe/patogenicidade , Magnaporthe/fisiologia , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Padrões de Referência , Estresse Fisiológico , Transcriptoma , Ubiquitina/genética
6.
Climacteric ; 15(2): 167-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22017345

RESUMO

OBJECTIVE: Vasoactive intestinal peptide (VIP) is a neuropeptide with elevated expression in regions that control urogenital functions. Estrogen appears to modulate VIP expression in various organs, but this effect has not been demonstrated in the vaginal wall. The aim of this study was to evaluate the influence of estrogen status on VIP expression in vessels of the vaginal wall. METHODS: Surgical specimens were removed from the vaginal walls of 18 premenopausal women and 12 postmenopausal women who were given surgery for genital prolapse grade I or II. Vaginal specimens were stained with estrogen receptor-alpha (ER-α) and VIP antibodies. Levels of follicle stimulating hormone (FSH), estradiol, prolactin, fasting glucose and serum thyroxine stimulating hormone were also measured. Estrogen status was assessed on the basis of FSH and ER-α scores. RESULTS: The vaginal walls of premenopausal women had significantly higher ER-α scores than those of menopausal women (premenopausal group, 3.6 ± 2.2; menopausal group, 1.4 ± 1.8; p = 0.01). Premenopausal women also had significantly higher levels of VIP in the vaginal wall than menopausal women (p = 0.02). Increasing age was associated with lower level of VIP staining (odds ratio 0.88; 95% confidence interval 0.78-0.99). CONCLUSION: Levels of ER-α and VIP expression in the posterior vaginal wall were higher in premenopausal than in menopausal women, but VIP expression was not associated with estrogen status. Age was an independent predictor of VIP staining in vaginal wall biopsies.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Menopausa/metabolismo , Vagina/irrigação sanguínea , Vagina/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Adulto , Fatores Etários , Glicemia/metabolismo , Vasos Sanguíneos/metabolismo , Índice de Massa Corporal , Estudos Transversais , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Menopausa/sangue , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Pré-Menopausa/sangue , Pré-Menopausa/metabolismo , Prolactina/sangue , Estatísticas não Paramétricas , Tireotropina/sangue , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-20953423

RESUMO

Eugenia dysenterica is a plant typically found in the Cerrado biome and commonly used in popular medicine due to its pharmacological properties, which include antidiarrheal, skin healing, and antimicrobial activities. The effects of ethanolic extract, aqueous extract and infusion of E. dysenterica leaves on intestinal motility and antidiarrheal activity were evaluated using ricin oil-induced diarrhea in rats. At doses of 400 and 800 mg·Kg(-1), the ethanolic extract decreased intestinal motility while the other extracts showed no significant effects. Moreover, serum levels of chloride, magnesium, and phosphorus were also measured in rats. Histopathologic and enzymatic analyses were also performed to investigate any toxic effect. Animals treated with infusion, ethanolic extract, ricin oil, and loperamide presented morphological alterations in the small intestine, such as mucosa lesion, epithelial layer damage, and partial loss and/or morphological change of villi. Furthermore, the liver showed congestion and hydropic degeneration. Serum levels of alanine aminotransferase increased significantly in all treatments, but none rose above reference values. In summary, our results suggest that compounds present in leaves of E. dysenterica may have therapeutic benefits on recovery from diarrhea despite their toxic effects.

8.
Clin Exp Obstet Gynecol ; 38(2): 119-22, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21793269

RESUMO

PURPOSE: To correlate ovarian reserve (OR) markers with response in assisted reproduction techniques (ART) and determine their ability to predict poor response among patients with endometriosis (EDT). METHODS: We evaluated ART cycles of 27 women with EDT and 50 with exclusive male factor. Basal follicle stimulating hormone (FSH) and anti-müllerian hormone (AMH) levels were determined. Ovarian response to gonadotropin stimulation was assessed and correlation coefficients calculated between the variables and reserve markers. Areas under the curve (AUC) determined ability of tests to predict poor response. RESULTS: AMH was significantly correlated with response in both groups and it was the only marker with significant discriminative capacity to predict poor response among EDT (AUC = 0.842; 95% CI: 0.651-0.952) and control group (AUC = 0.869; 95% CI: 0.743-0.947). CONCLUSION: Infertile patients with endometriosis can benefit from the pre-therapeutic assessment of OR markers. However, regardless of disease presence, only AMH predicts poor response to stimulus.


Assuntos
Hormônio Antimülleriano/sangue , Endometriose/sangue , Hormônio Foliculoestimulante/sangue , Ovário/fisiologia , Indução da Ovulação/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Endometriose/complicações , Endometriose/terapia , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Masculina , Masculino , Curva ROC
9.
Hum Reprod ; 25(8): 2124-31, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20573680

RESUMO

BACKGROUND: There is evidence that intrauterine growth restriction, resulting in newborn girls that are small for gestational age (SGA), may be related to the onset of polycystic ovary syndrome (PCOS). Thus, we studied whether women born SGA have a higher prevalence of PCOS than women born appropriate for gestational age (AGA). METHODS: This was a prospective birth cohort study of 384 women born at term between June 1, 1978, and May 31, 1979, in Ribeirão Preto, Brazil. After exclusion, 165 women effectively participated in this study, of whom 43 were SGA and 122 were AGA. The prevalence of PCOS was analysed. At a mean age of 29 years, the women agreed to follow the study protocol, which included: anamnesis, physical examination, serum tests [follicle stimulating hormone, luteinizing hormone, total and free testosterone, dehydroepiandrostenedione sulphate, 17-OH-progesterone, fasting insulin, sex steroid-binding globulin (SHBG) and fasting glucose] and pelvic ultrasound. Data regarding gestational age, birthweight, age at menarche and maternal data were obtained from the files of the cohort. The adjusted relative risk (RR) values of the SGA, insulin resistance, body mass index, maternal smoking and parity variables were analysed using Poisson regression with robust adjustment of variance for the prediction of PCOS. RESULTS: The prevalence of PCOS was higher in the SGA group than in the AGA group [adjusted RR = 2.44, 95% CI (1.39-4.28)]. Hyperandrogenism was more prevalent in the SGA women than in the AGA women (P = 0.011). Circulating SHBG was lower in the SGA women than in the AGA women (P = 0.041), but fasting insulinemia was similar in both groups. CONCLUSIONS: The prevalence of PCOS in SGA women was twice as high as in AGA women in our study population.


Assuntos
Peso ao Nascer , Síndrome do Ovário Policístico/epidemiologia , Adulto , Feminino , Idade Gestacional , Humanos , Distribuição de Poisson , Síndrome do Ovário Policístico/sangue , Prevalência , Estudos Prospectivos , Análise de Regressão , Fatores de Risco
10.
J Cell Biol ; 107(4): 1517-30, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2459130

RESUMO

The small RNP complexes of defined morphology and biochemical composition termed prosomes, first isolated from the cytoplasm associated with repressed mRNA (Martins de Sa, C., M.-F. Grossi de Sa, O. Akhayat, F. Broders, and K. Scherrer. J. Mol. Biol. 1986. 187:47-493), were found also in the nucleus (Grossi de Sa, M.-F., C. Martins de Sa, F. Harper, O. Coux, O. Akhayat, P. Gounon, J. K. Pal, Y. Florentin, and K. Scherrer. 1988. J. Cell Sci. 89:151-165). Immunofluorescence, immunoelectron microscopy, and immunochemical studies using mAbs directed against some of the prosomal proteins of duck erythroblasts indicate that in the cytoplasm of HeLa and PtK cells, prosome antigens are associated with the intermediate filament network of the cytokeratin type.


Assuntos
Citoesqueleto/ultraestrutura , Filamentos Intermediários/ultraestrutura , Ribonucleoproteínas/metabolismo , Citoesqueleto de Actina/ultraestrutura , Animais , Western Blotting , Linhagem Celular , Citosol/metabolismo , Imunofluorescência , Humanos , Imuno-Histoquímica , Filamentos Intermediários/metabolismo , Queratinas , Camundongos , Microscopia Eletrônica , Peso Molecular , Vimentina
11.
Int J Clin Pract ; 63(1): 160-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18795969

RESUMO

Chronic anovulation, polycystic ovarian morphology and hyperandrogenism are the diagnostic criteria for polycystic ovary syndrome (PCOS). Metabolic disturbances are more common in PCOS women who are prone to develop metabolic syndrome and to present higher levels of some cardiovascular disease risk marker. Oral contraceptives are widely used in PCOS, but conflicting data have been reported regarding their impact on carbohydrate and lipid metabolism on PCOS women. This paper presents a critical evaluation of combined oral contraceptives (COCs) metabolic effect - carbohydrate metabolism and insulin sensitivity, lipid metabolism, haemostasis, body weight, arterial pressure and cardiovascular impact - on PCOS women. Because of the paucity of data on the impact of COCs on cardiovascular and metabolic parameters in PCOS patients, most of there commendations are based on studies involving ovulatory women. The use of low-dose COCs is preferable in PCOS, especially among patients with glucose intolerance, insulin resistance and uncomplicated diabetes mellitus. Although reported as a side effect of COCs, marked weight gain has not been confirmed among users. However, when arterial hypertension or elevated risk for thromboembolism is present, progestogen-only hormonal contraceptives should be used instead of COCs. Regarding dyslipidaemia, COCs reduce low-density lipoprotein and total cholesterol and elevate high-density lipoprotein and triglycerides, and therefore are not recommended for women with high triglycerides levels. The choice of a COC, which alleviates the PCOS-induced hyperandrogenism without significant negative impact on cardiovascular risk, is one of the greatest challenges faced by gynaecologists nowadays.


Assuntos
Anticoncepcionais Orais Combinados/uso terapêutico , Doenças Metabólicas/induzido quimicamente , Síndrome do Ovário Policístico/tratamento farmacológico , Adulto , Anticoncepcionais Orais Combinados/efeitos adversos , Métodos Epidemiológicos , Feminino , Humanos , Pessoa de Meia-Idade , Aumento de Peso/efeitos dos fármacos
12.
Bull Entomol Res ; 98(6): 575-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18590601

RESUMO

The biochemical properties of the digestive alpha-amylase from Tecia solanivora larvae, an important and invasive insect pest of potato (Solanum tuberosum), were studied. This insect has three major digestive alpha-amylases with isoelectric points 5.30, 5.70 and 5.98, respectively, which were separated using native and isoelectric focusing gels. The alpha-amylase activity has an optimum pH between 7.0 and 10.0 with a peak at pH 9.0. The enzymes are stable when heated to 50 degrees C and were inhibited by proteinaceous inhibitors from Phaseolus coccineus (70% inhibition) and P. vulgaris cv. Radical (87% inhibition) at pH 6.0. The inhibitors present in an amaranth hybrid inhibited 80% of the activity at pH 9.0. The results show that the alpha-amylase inhibitor from amaranth seeds may be a better candidate to make genetically-modified potatoes resistant to this insect than inhibitors from common bean seeds.


Assuntos
Inibidores Enzimáticos/química , Mariposas/enzimologia , Proteínas de Plantas/química , alfa-Amilases/química , Animais , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Larva/enzimologia , Mariposas/crescimento & desenvolvimento , Temperatura , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/fisiologia
13.
Peptides ; 28(10): 2042-50, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17875343

RESUMO

Canatoxin, a urease isoform from Canavalia ensiformis seeds, shows insecticidal activity against different insect species. Its toxicity relies on an internal 10 kDa peptide (pepcanatox), released by hydrolysis of Canatoxin by cathepsins in the digestive system of susceptible insects. In the present work, based on the N-terminal sequence of pepcanatox, we have designed primers to amplify by PCR a 270-bp fragment corresponding to pepcanatox using JBURE-II cDNA (one of the urease isoforms cloned from C. ensiformis, with high identity to JBURE-I, the classical urease) as a template. This amplicon named jaburetox-2 was cloned into pET 101 vector to obtain heterologous expression in Escherichia coli of the recombinant protein in C-terminal fusion with V-5 epitope and 6-His tag. Jaburetox-2Ec was purified on Nickel-NTA resin and bioassayed in insect models. Dysdercus peruvianus larvae were fed on cotton seed meal diets containing 0.01% (w/w) Jaburetox-2Ec and, after 11 days, all individuals were dead. Jaburetox-2Ec was also tested against Spodoptera frugiperda larvae and caused 100% mortality. In contrast, high doses of Jaburetox-2Ec were innocuous when injected or ingested by mice and neonate rats. Modeling of Jaburetox-2Ec, in comparison with other peptide structures, revealed a prominent beta-hairpin motif consistent with an insecticidal activity based on either neurotoxicity or cell permeation.


Assuntos
Canavalia/enzimologia , Inseticidas/isolamento & purificação , Urease/química , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Inseticidas/química , Inseticidas/toxicidade , Dados de Sequência Molecular , Proteínas de Plantas , Reação em Cadeia da Polimerase , Homologia de Sequência de Aminoácidos , Urease/genética , Urease/isolamento & purificação , Urease/toxicidade
14.
Peptides ; 28(6): 1292-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17485144

RESUMO

Acanthoscelides obtectus is a devastating storage insect pest capable of causing severe bean crop losses. In order to maintain their own development, insect pest larvae feed continuously, synthesizing efficient digestive enzymes. Among them, cysteine proteinases (CPs) are commonly produced as inactive precursors (procysteines), requiring a cleavage of the peptide proregion to become active. The proregion fits tightly into the active site of procysteines, efficiently preventing their activity. In this report, a CP cDNA (cpao) was isolated from A. obtectus midgut larvae. In silico studies indicated that the complete CP sequence contains a hydrophobic signal peptide, a prodomain and a conserved catalytic region. Moreover, the encoding cDNA contains 963bp translating into a 321 residue protein, CPAo, which was expressed in E. coli, fused with thioredoxin. Enzymatic assays using the recombinant protein revealed that the enzyme was catalytically active, being able to cleave the synthetic substrate Z-Phe-Arg-7-AMC. Additionally, this report also focuses the cpao propeptide (PCPAo) subcloning and expression. The expressed propeptide efficiently inhibited CPAo, as well as digestive CP of other bean bruchids. Little or no activity was found against proteolytic enzymes of two other coleopterans: Rhyzopertha dominica and Anthonomus grandis. The data reported here indicate the possibility of endogenous propeptides as a novel strategy on bruchids control, which could be applicable to bean improvement programs.


Assuntos
Besouros/enzimologia , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Clonagem Molecular , Sequência Conservada , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/isolamento & purificação , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/genética , DNA Complementar/genética , Escherichia coli/genética , Dados de Sequência Molecular , Ligação Proteica , Sinais Direcionadores de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Tiorredoxinas/metabolismo
15.
Mol Cell Biol ; 9(6): 2672-81, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2503709

RESUMO

Prosomes and heat shock protein (HSP) complexes isolated from the cytoplasm of Drosophila cells in culture were biochemically and immunologically characterized. The two complexes were found to separate on sucrose gradients, allowing the analysis of their protein constituents by two-dimensional polyacrylamide gel electrophoresis and by reaction with anti-HSP sera and prosome-specific monoclonal antibodies. All of the prosomal proteins were found to be clearly distinct from the HSP; none of the prosomal proteins was synthesized de novo in heat shock. However, an antiprosome (anti-p27K) monoclonal antibody (mouse anti-duck) recognizing the Drosophila p29K prosomal protein allowed immunoprecipitation from a heat-shocked postmitochondrial supernatant of the crude HSP complex, including the low- and the high-molecular-weight components, in particular the 70 x 10(3)-molecular weight HSP. The highly purified small 16S HSP complex still contained this preexistent p29K prosomal protein, which thus also seems to be a metabolically stable constituent of the HSP complex. The significance of this structural and possibly functional relationship between prosomes and HSP, involving the highly ubiquitous and evolutionarily conserved prosomal protein p27/29K, remains to be elucidated.


Assuntos
Drosophila melanogaster/análise , Proteínas de Choque Térmico/análise , Ribonucleoproteínas/análise , Animais , Anticorpos Monoclonais , Evolução Biológica , Fracionamento Celular , Núcleo Celular/análise , Células Cultivadas , Centrifugação com Gradiente de Concentração , Citoplasma/análise , Drosophila melanogaster/citologia , Eletroforese em Gel de Poliacrilamida , Immunoblotting , Peso Molecular , Mapeamento de Peptídeos , Testes de Precipitina
16.
Braz J Med Biol Res ; 40(4): 491-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17401492

RESUMO

The aim of the present study was to determine whether estrogen therapy (ET) reduces alterations of the autonomic control of heart rate (HR) due to hypoestrogenism and aging. Thirteen young (24 +/- 2.6 years), 10 postmenopausal (53 +/- 4.6 years) undergoing ET (PM-ET), and 14 postmenopausal (56 +/- 2.6 years) women not undergoing ET (PM) were studied. ET consisted of 0.625 mg/day conjugated equine estrogen. HR was recorded continuously for 8 min at rest in the supine and sitting positions. HR variability (HRV) was analyzed by time (SDNN and rMSSD indices) and frequency domain methods. Power spectral components are reported as normalized units (nu) at low (LF) and high (HF) frequencies, and as LF/HF ratio. Intergroup comparisons: SDNN index was higher in young (median: supine, 47 ms; sitting, 42 ms) than in PM-ET (33; 29 ms) and PM (31; 29 ms) women (P < 0.05). PM showed lower HFnu, higher LFnu and higher LF/HF ratio (supine: 44, 56, 1.29; sitting: 38, 62, 1.60) than the young group in the supine position (61, 39, 0.63) and the PM-ET group in the sitting position (57, 43, 0.75; P < 0.05). Intragroup comparisons: HR was lower in the supine than in the sitting position for all groups (P < 0.05). The HRV decrease from the supine to the sitting position was significant only in the young group. These results suggest that HRV decreases during aging. ET seems to attenuate this process, promoting a reduction in sympathetic activity on the heart and contributing to the cardioprotective effect of estrogen hormones.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Estrogênios Conjugados (USP)/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Coração/inervação , Pós-Menopausa/fisiologia , Adulto , Sistema Nervoso Autônomo/fisiologia , Doenças Cardiovasculares/prevenção & controle , Estudos Transversais , Feminino , Frequência Cardíaca/fisiologia , Humanos , Pessoa de Meia-Idade , Postura
17.
Braz J Med Biol Res ; 40(4): 501-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17401493

RESUMO

Several methods are used to estimate anaerobic threshold (AT) during exercise. The aim of the present study was to compare AT obtained by a graphic visual method for the estimate of ventilatory and metabolic variables (gold standard), to a bi-segmental linear regression mathematical model of Hinkley's algorithm applied to heart rate (HR) and carbon dioxide output (VCO2) data. Thirteen young (24 +/- 2.63 years old) and 16 postmenopausal (57 +/- 4.79 years old) healthy and sedentary women were submitted to a continuous ergospirometric incremental test on an electromagnetic braking cycloergometer with 10 to 20 W/min increases until physical exhaustion. The ventilatory variables were recorded breath-to-breath and HR was obtained beat-to-beat over real time. Data were analyzed by the nonparametric Friedman test and Spearman correlation test with the level of significance set at 5%. Power output (W), HR (bpm), oxygen uptake (VO2; mL kg(-1) min(-1)), VO2 (mL/min), VCO2 (mL/min), and minute ventilation (VE; L/min) data observed at the AT level were similar for both methods and groups studied (P > 0.05). The VO2 (mL kg(-1) min(-1)) data showed significant correlation (P < 0.05) between the gold standard method and the mathematical model when applied to HR (rs = 0.75) and VCO2 (rs = 0.78) data for the subjects as a whole (N = 29). The proposed mathematical method for the detection of changes in response patterns of VCO2 and HR was adequate and promising for AT detection in young and middle-aged women, representing a semi-automatic, non-invasive and objective AT measurement.


Assuntos
Limiar Anaeróbio/fisiologia , Dióxido de Carbono/metabolismo , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Adulto , Algoritmos , Eletrocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Teóricos
18.
Biochim Biophys Acta ; 1490(1-2): 87-98, 2000 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-10786620

RESUMO

Arcelins are insecticidal proteins found in some wild accessions of the common bean, Phaseolus vulgaris. They are grouped in six allelic variants and arcelin-5 is the variant with the highest inhibitory effect on the development of Zabrotes subfasciatus larvae. Characterization of the protein and its genes resulted in the identification of three polypeptides and the isolation of two genes that encode the Arc5a and Arc5b polypeptides. Here we describe a new gene, Arc5-III. The protein it encodes has 81% amino acid identity with the derived amino acid sequences of Arc5-I and Arc5-II. The Arc5-III gene is highly expressed in developing seeds and at a much lower level in roots. Data obtained by a combination of two-dimensional gel electrophoresis, protein sequencing and MALDI-TOF mass spectrometry analysis support the conclusion that Arc5-III encodes a polypeptide present in Arc5c band. Using ion-exchange chromatography, three fractions containing arcelin-5 polypeptides were eluted by increasing the salt concentration. The three fractions contain various amounts of the three arc-5 polypeptides and inhibit the growth of Zabrotes subfasciatus larvae differentially, suggesting differences in insecticidal activity among the arcelin-5 isoforms.


Assuntos
Glicoproteínas/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Escherichia coli/metabolismo , Fabaceae/genética , Glicoproteínas/biossíntese , Glicoproteínas/farmacologia , Inseticidas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Dados de Sequência Molecular , Proteínas de Plantas/biossíntese , Proteínas de Plantas/farmacologia , Plantas Medicinais , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Alinhamento de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transfecção
19.
J Mol Biol ; 187(4): 479-93, 1986 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-2423694

RESUMO

The "prosomes", a novel type of ubiquitous ribonucleoprotein particle of extraordinary stability and of defined electron microscopical structure, have been characterized in several cell types and species. Identified as a 19 S sub-component of free mRNA-protein complexes, including globin and other repressed mRNA, in the cytoplasm of duck, mouse and HeLa cells, they were previously found to inhibit protein synthesis in vitro. In all cells studied, electron microscopy shows an identical, seemingly ring-like but rather raspberry-shaped particle of 12 nm diameter, resistant to EDTA and 1% (w/v) Sarkosyl. Two-dimensional electrophoretic analysis of prosomal proteins shows a characteristic pattern in the 19,000 to 35,000 Mr range of pI 4 to 7, with an additional 56,000 Mr component specific to avian species. The prosomes found in globin mRNA-protein complexes contain about 25 protein components, 16 of which have identical molecular weight and pI values in duck and mouse, and which are also found in the prosomes of the heterogeneous free mRNPs of HeLa cells. Seral and monoclonal antibodies raised in mice against the prosomes of duck erythroblasts cross-react with some of the proteins of the mouse and HeLa cell particles. Prosomes isolated from duck and mouse globin mRNP, both contain small cytoplasmic RNAs of 70 to 90 nucleotides, which represent about 15% of the particle mass. The molecular weight and the 3'-terminal oligonucleotide of each one of these small cytoplasmic RNAs are identical in the two animal species; fingerprints of their oligonucleotides generated by RNase T1 show that more than 80% of spots are identical. In contrast, the prosomes of HeLa cells, associated with a large population of repressed mRNA, contain at least 12 small cytoplasmic RNA species. All prosomal RNAs tested so far hybridize to mRNA. The data available indicate that prosomes constitute a novel class of ubiquitous cellular ribonucleoprotein complexes, present in the nucleus and cytoplasm that, in its structural variations shown here, reflects function and species.


Assuntos
Ribonucleoproteínas/análise , Animais , Composição de Bases , Centrifugação com Gradiente de Concentração , Patos , Eletroforese em Gel de Poliacrilamida , Eritroblastos/ultraestrutura , Células HeLa/ultraestrutura , Humanos , Camundongos , Peso Molecular , Hibridização de Ácido Nucleico , RNA/análise , RNA Mensageiro , RNA Citoplasmático Pequeno , Ribonucleoproteínas/imunologia
20.
Protein Pept Lett ; 12(6): 583-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16101400

RESUMO

A 6.5 kDa serine protease inhibitor was purified by anion-exchange chromatography from the crude extract of the Inga umbratica seeds, containing inhibitor isoforms ranging from 6.3 to 6.7 kDa and protease inhibitors of approximately 19 kDa. The purified protein was characterized as a potent inhibitor against trypsin and chymotrypsin and it was named I. umbratica trypsin and chymotrypsin inhibitor (IUTCI). MALDI-TOF spectra of the IUTCI, in the presence of DTT, showed six disulfide bonds content, suggesting that this inhibitor belongs to Bowman-Birk family. The circular dichroism spectroscopy indicates that IUTCI is predominantly formed by unordered and beta-sheet secondary structure. It was also characterized, by fluorescence spectroscopy, as a stable protein at range of pH from 5.0 to 7.0. Moreover, this inhibitor at concentration of 75 microM presented a remarkable inhibitory activity (60%) against digestive serine proteases from boll weevil Anthonomus grandis, an important economical cotton pest.


Assuntos
Fabaceae/química , Sementes/química , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/isolamento & purificação , Inibidores de Serina Proteinase/farmacologia , Gorgulhos/enzimologia , Cromatografia por Troca Iônica , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Peso Molecular , Inibidores de Serina Proteinase/química , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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