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951.
da Silveira RB Pigozzo RB Chaim OM Appel MH Silva DT Dreyfuss JL Toma L Dietrich CP Nader HB Veiga SS Gremski W 《Biochimie》2007,89(3):289-300
Loxoscelism (the condition produced by the bite of brown spiders) has been reported worldwide, but especially in warmer regions. Clinical manifestations include skin necrosis with gravitational spreading while systemic loxoscelism may include renal failure, hemolysis and thrombocytopenia. The venom contains several toxins, of which the best biochemically and biologically studied is the dermonecrotic toxin, a phospholipase-D. Purified toxin induces cutaneous and systemic loxoscelism, especially necrotic lesions, hematological disturbances and renal failure. Herein, we describe cloning, heterologous expression and purification of two novel dermonecrotic toxins: LiRecDT4 and LiRecDT5. The recombinant proteins stably expressed in Escherichia coli cells were purified from culture supernatants in a single step using Ni(2+)-chelating chromatography producing soluble proteins of 34 kDa (LiRecDT4) and 37 kDa (LiRecDT5). Circular dichroism analysis evidenced correctly folding for toxins but differences in secondary structures. Both proteins were recognized by whole venom serum antibodies and by a specific antibody to dermonecrotic toxin. Also, recombinant toxins with phospholipase activity induced experimental skin lesions and caused a massive inflammatory response in rabbit skin dermis. Nevertheless, toxins displayed different effects upon platelet aggregation, increase in vascular permeability and not caused death in mice. These characteristics in combination with functional studies illustrates that a family of dermonecrotic toxins exists, and includes two novel members that are useful for future structural and functional studies. They will also be useful in biotechnological ends, for example, as inflammatory and platelet aggregating studies, as antigens for serum therapy source and for lipids biochemical research. 相似文献
952.
Developmental models for skin exist in terrestrial and amphibious vertebrates but there is a lack of information in aquatic
vertebrates. We have analysed skin epidermal development of a bony fish (teleost), the most successful group of extant vertebrates.
A specific epidermal type I keratin cDNA (hhKer1), which may be a bony-fish-specific adaptation associated with the divergence of skin development (scale formation) compared
with other vertebrates, has been cloned and characterized. The expression of hhKer1 and collagen 1α1 in skin taken together with the presence or absence of keratin bundle-like structures have made it possible to distinguish
between larval and adult epidermal cells during skin development. The use of a flatfish with a well-defined larval to juvenile
transition as a model of skin development has revealed that epidermal larval basal cells differentiate directly to epidermal
adult basal cells at the climax of metamorphosis. Moreover, hhKer1 expression is downregulated at the climax of metamorphosis and is inversely correlated with increasing thyroxin levels. We
suggest that, whereas early mechanisms of skin development between aquatic and terrestrial vertebrates are conserved, later
mechanisms diverge.
This work was carried out within the project “Arrested development: The Molecular and Endocrine Basis of Flatfish Metamorphosis”
(Q5RS-2002-01192) with financial support from the Commission of the European Communities. It does not necessarily reflect
the Commission’s views and in no way anticipates its future policy in this area. This project was further supported by Pluriannual
funding to CCMAR by the Portuguese Science and Technology Council. M.A. Campinho was sponsored by the Portuguese Ministry
of Science (grant no. SFRH/BD/6133/2001). 相似文献
953.
Passos XS Costa CR Araújo CR Nascimento ES e Souza LK Fernandes Ode F Sales WS Silva Mdo R 《Mycopathologia》2007,163(3):145-151
In this work, we collect data from surveys of bloodstream Candida isolates performed in Brazil from 1996 to 2004. Besides, we analyzed the species distribution of bloodstream Candida isolates together with potential risk factors for candidemia and the susceptibility profile of these isolates in patients
from Hospital das Clínicas in Goiania city, Brazil. Blood samples were collected in the admission day and on every 7 days,
in the intensive care unit (ICU) of a tertiary hospital. Candida isolates were identified by standard protocols that included germ tube formation, chlamydoconidia production on cornmeal
agar and sugar fermentation and assimilation tests. Data of patients were recorded and analyzed according to age at the time
of diagnosis, gender and presence of potential risk factors. Statistical analysis was used to determine if the time of hospital
permanence increased Candida colonization in ICU patients’ blood. The antifungal susceptibility testing was performed by broth microdilution method according
to document NCCLS/CLSI M27–A2. Among the 345 blood samples cultured, candidemia was recovered in 33 patients, which were isolated
51.5% of Candida non-albicans. Fungemia was associated with long-term hospitalization. Fluconazole, itraconzole, voriconazole and amphotericin B exhibited
a potent activity against all isolates of Candida. Voriconazole MICs were much low for all isolates tested. This work confirms data of increase of Candida non-albicans species in bloodstream in ICU and shows that voriconazole in vitro activity was higher than those of itraconazole, fluconazole and amphotericin B. 相似文献
954.
Tarsitano CA Paffaro VA Pauli JR da Silva GH Saad MJ Salgado I da Cruz-Höfling MA Hyslop S 《Cell and tissue research》2007,329(1):45-58
Chronic treatment of rats with N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) biosynthesis, results in hypertension mediated partly by enhanced angiotensin-I-converting enzyme (ACE) activity. We examined the influence of L-NAME on rat liver morphology, on hepatic glycogen, cholesterol, and triglyceride content, and on the activities of the cytochrome P450 isoforms CYP1A1/2, CYP2B1/2, CYP2C11, and CYP2E1. Male Wistar rats were treated with L-NAME (20 mg/rat per day via drinking water) for 2, 4, and 8 weeks, and their livers were then removed for analysis. Enzymatic induction was produced by treating rats with phenobarbital (to induce CYP2B1/2), beta-naphthoflavone (to induce CYP1A1/2), or pyrazole (to induce CYP2E1). L-NAME significantly elevated blood pressure; this was reversed by concomitant treatment with enalapril (ACE inhibitor) or losartan (angiotensin II AT(1) receptor antagonist). L-NAME caused vascular hypertrophy in hepatic arteries, with perivascular and interstitial fibrosis involving collagen deposition. Hepatic glycogen content also significantly increased. L-NAME did not affect fasting glucose levels but significantly reduced insulin levels and increased the insulin sensitivity of rats, based on an intraperitoneal glucose tolerance test. Immunoblotting experiments indicated enhanced phosphorylation of protein kinase B and of glycogen synthase kinase 3. All these changes were reversed by concomitant treatment with enalapril or losartan. L-NAME had no effect on hepatic cholesterol or triglyceride content or on the basal or drug-induced activities and protein expression of the cytochrome P450 isoforms. Thus, the chronic inhibition of NO biosynthesis produced hepatic morphological alterations and changes in glycogen metabolism mediated by the renin-angiotensin system. The increase in hepatic glycogen content probably resulted from enhanced glycogen synthase activity following the inhibition of glycogen synthase kinase 3 by phosphorylation. 相似文献
955.
Gesteira AS Micheli F Carels N Da Silva AC Gramacho KP Schuster I Macêdo JN Pereira GA Cascardo JC 《Annals of botany》2007,100(1):129-140
BACKGROUND AND AIMS: Witches' broom disease is caused by the hemibiotrophic basidiomycete Moniliophthora perniciosa, and is one of the most important diseases of cacao in the western hemisphere. Because very little is known about the global process of such disease development, expressed sequence tags (ESTs) were used to identify genes expressed during the Theobroma cacao-Moniliophthora perniciosa interaction. METHODS: Two cDNA libraries corresponding to the resistant (RT) and susceptible (SP) cacao-M. perniciosa interactions were constructed from total RNA, using the DB SMART Creator cDNA library kit (Clontech). Clones were randomly selected, sequenced from the 5' end and analysed using bioinformatics tools including in silico analysis of the differential gene expression. KEY RESULTS: A total of 6884 ESTs were generated from the RT and SP cDNA libraries. These ESTs were composed of 2585 singlets and 341 contigs for a total of 2926 non-redundant sequences. The redundancy of the libraries was low and their specificity high when compared with the few other cacao libraries already published. Sequence analysis allowed the assignment of a putative functional category for 54 % of sequences, whereas approx. 22 % of sequences corresponded to unknown function and approx. 24 % of sequences did not show any significant similarity with other proteins present in the database. Despite the similar overall distribution of the sequences in functional categories between the two libraries, qualitative differences were observed. Genes involved during the defence response to pathogen infection or in programmed cell death were identified, such as pathogenesis related-proteins, trypsin inhibitor or oxalate oxidase, and some of them showed an in silico differential expression between the resistant and the susceptible interactions. CONCLUSIONS: As far as is known this is the first EST resource from the cacao-M. perniciosa interaction and it is believed that it will provide a significant contribution to the understanding of the molecular mechanisms of the resistance and susceptibility of cacao to M. perniciosa, to develop strategies to control witches' broom, and as a source of polymorphism for molecular marker development and marker-assisted selection. 相似文献
956.
Inada NM da Silva AR Jorge RA Borecký J Vercesi AE 《Archives of biochemistry and biophysics》2007,457(2):217-224
The action of irradiated cationic Fe(III)TMPyP and anionic Fe(III)TPPS4 forms of mesoporphyrins on mitochondrial functions was investigated using experimental conditions that caused minimal effects on mitochondria in the dark. Treatment of mitochondria with 1 microM Fe(III)TMPyP for 2 min decreased the respiratory control by 3% in the dark and 28% after irradiation. Fe(III)TPPS4 (1 microM) had no significant effect on respiratory control under any of the above conditions. Both porphyrins increased the mitochondrial production of reactive oxygen species in the presence of Ca2+; however, the effect of Fe(III)TMPyP was significantly stronger. In both cases, this overproduction was associated with membrane lipid peroxidation. It was also observed that the association constant of Fe(III)TMPyP with mitochondria was 11 times higher than that of Fe(III)TPPS4. In conclusion, the damage to isolated mitochondria induced by Fe(III)TMPyP under illumination was larger than by Fe(III)TPPS4, probably because its cationic charge favors association with the mitochondrial membrane. This is supported by the decrease in the association constant of Fe(III)TMPyP with mitochondria in higher salt medium. 相似文献
957.
Validation of endogenous control genes in human adipose tissue: relevance to obesity and obesity-associated type 2 diabetes mellitus. 总被引:2,自引:0,他引:2
V Catalán J Gómez-Ambrosi F Rotellar C Silva A Rodríguez J Salvador M J Gil J A Cienfuegos G Frühbeck 《Hormones et métabolisme》2007,39(7):495-500
The aim of the present study was to test the influence of obesity and the presence of type 2 diabetes mellitus (T2DM) on the expression of ten housekeeping genes and of the 18S rRNA in a group of human adipose tissue samples from the omental and subcutaneous depot. Adipose tissue biopsies were obtained by laparoscopic surgery from lean and obese patients. After the extraction, mRNA levels in adipose tissue samples were quantified by real-time PCR using the commercial HUMAN ENDOGENOUS CONTROL PLATES. From the genes analyzed, 18S rRNA exhibited the most stable expression levels in both depots regardless of the pathophysiological conditions of obesity and obesity-associated T2DM. Contrarily, GAPD was the gene with the highest variation in its expression levels, being upregulated (8.0-fold) in the obese group and downregulated (3.5-fold) in obesity-associated T2DM. Our results show that 18S rRNA may be the most suitable gene for normalization in expression studies performed in human adipose tissue samples obtained from patients suffering from obesity and/or obesity-associated T2DM, whereas GAPD is less appropriate for comparison purposes under these circumstances. 相似文献
958.
Glasnović M Bosnjak I Vcev A Soldo I Kosuta M Lenz B Glasnović-Horvatić E Soldo-Butković S Mićunović N 《Collegium antropologicum》2007,31(1):173-177
The aim of the research was to show our diagnostic and therapeutic experience with antiphospholipid syndrome (APS) in pregnant women. 36 pregnant women suspect on APS were included in the study: 32 with primary antiphospholipd syndrome (PAPS) and 4 with secondary antiphospholipid syndrome (SAPS). All pregnant women received low-molecular-weight-heparin (LMWH) and low dose aspirin (LDA) therapy. Control group represented 26 women with SAPS and previous bad reproductive anamnesis. Average pregnancy lasted 37.06 +/- 0.707 weeks. LMWH and LDA therapy was successful in 97.22%. Lupus anticoagulant (LA) was found to be more frequent in PAPS group (71.87%). Anticardiolipin antibodies (aCL) were found to be more frequent in SAPS (26.66%). For three patients (3.37%), PAPS was diagnosed due to a fact that they had positive antibeta2-glycoproteinl (antibeta-GP1). To make APS diagnosis, it is of great importance to search for all antiphospholipid antibodies. LMWH and low dose of acetylsalicylic acid should be the first choice therapy. 相似文献
959.
Ferreira AJ Jacoby BA Araújo CA Macedo FA Silva GA Almeida AP Caliari MV Santos RA 《American journal of physiology. Heart and circulatory physiology》2007,292(2):H1113-H1119
The nonpeptide AVE-0991, which has been reported as a selective ligand for the angiotensin-(1-7) [ANG-(1-7)] receptor Mas, has actions similar to those attributed to the cardioprotective product of the renin-angiotensin system, ANG-(1-7). In this study, we evaluated the cardiac effects of AVE-0991 in normal and infarcted male Wistar rats. Myocardial infarction was induced by left coronary artery ligation. At the end of the treatment, the Langendorff technique was used to analyze cardiac function. Left ventricle serial sections were dyed with Gomori trichrome stain to quantify the infarcted area. In normal hearts, AVE-0991 produced a significant decrease in perfusion pressure and an increase in systolic tension, rate of tension rise and fall (+/-dT/dt), and heart rate. These effects were completely blocked by the perfusion of the hearts with a solution containing the selective ANG-(1-7) antagonist A-779. N(G)-nitro-l-arginine methyl ester treatment abolished the AVE-0991-induced vasodilation in isolated hearts. AVE-0991 significantly attenuated the decrease in systolic tension (sham operated, 13.00 +/- 1.02 g; infarction, 7.18 +/- 0.66 g; AVE treated, 9.23 +/- 1.05 g, n = 5), +dT/dt, -dT/dt, and heart rate induced by myocardial infarction. Infarction-induced vasoconstriction was completely prevented by AVE-0991 treatment. Furthermore, AVE-0991 significantly decreased the infarcted area (6.98 +/- 1.01 vs. 3.94 +/- 1.04 mm(2) in AVE-treated rats). These data indicate that the compound AVE-0991 produces beneficial effects in isolated perfused rat hearts involving the ANG-(1-7) receptor Mas and the release of nitric oxide. In addition, our results indicate that AVE-0991 attenuates postischemic heart failure. 相似文献
960.