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51.

Background

There is substantial evidence that chronic renal and cardiovascular diseases are associated with coagulation disorders, endothelial dysfunction, inflammation and fibrosis. Angiotensin-Converting Enzyme Insertion/Deletion polymorphism (ACE I/D polymorphism) has also be linked to cardiovascular diseases. Therefore, this study aimed to compare plasma levels of ultrassensible C-reactive protein (usCRP), PAI-1, D-dimer and TGF-β1 in patients undergoing HD with different ACE I/D polymorphisms.

Methods

The study was performed in 138 patients at ESRD under hemodialysis therapy for more than six months. The patients were divided into three groups according to the genotype. Genomic DNA was extracted from blood cells (leukocytes). ACE I/D polymorphism was investigated by single polymerase chain reaction (PCR). Plasma levels of D-dimer, PAI-1 and TGF-β1 were measured by enzyme-linked immunosorbent assay (ELISA), and the determination of plasma levels of usCRP was performed by immunonephelometry. Data were analyzed by the software SigmaStat 2.03.

Results

Clinical characteristics were similar in patients with these three ACE I/D polymorphisms, except for interdialytic weight gain. I allele could be associated with higher interdialytic weight gain (P = 0.017). Patients genotyped as DD and as ID had significantly higher levels of PAI-1 than those with II genotype. Other laboratory parameters did not significantly differ among the three subgroups (P = 0.033). Despite not reaching statistical significance, plasma levels of usCRP were higher in patients carrying the D allele.

Conclusion

ACE I/D polymorphisms could be associated with changes in the regulation of sodium, fibrinolytic system, and possibly, inflammation. Our data showed that high levels of PAI-1 are detected when D allele is present, whereas greater interdialytic gain is associated with the presence of I allele. However, further studies with different experimental designs are necessary to elucidate the mechanisms involved in these associations.  相似文献   
52.
The small heat shock proteins (smHSPs) belong to a family of proteins that function as molecular chaperones by preventing protein aggregation and are also known to contain a conserved region termed alpha-crystallin domain. Here, we report the expression, purification, and partial characterization of a novel smHSP (HSP17.9) from the phytopathogen Xylella fastidiosa, causal agent of the citrus variegated chlorosis (CVC). The gene was cloned into a pET32-Xa/LIC vector to over-express the protein coupled with fusion tags in Escherichia coli BL21(DE3). The expressed HSP17.9 was purified by immobilized metal affinity chromatography (IMAC) and had its identity determined by mass spectrometry (MALDI-TOF). The correct folding of the purified recombinant protein was verified by circular dichroism spectroscopy. Finally, the HSP17.9 protein also proved to efficiently prevent induced aggregation of insulin, strongly indicating a chaperone-like activity.  相似文献   
53.
We developed a database system for collaborative HIV analysis (DBCollHIV) in Brazil. The main purpose of our DBCollHIV project was to develop an HIV-integrated database system with analytical bioinformatics tools that would support the needs of Brazilian research groups for data storage and sequence analysis. Whenever authorized by the principal investigator, this system also allows the integration of data from different studies and/or the release of the data to the general public. The development of a database that combines sequences associated with clinical/epidemiological data is difficult without the active support of interdisciplinary investigators. A functional database that securely stores data and helps the investigator to manipulate their sequences before publication would be an attractive tool for investigators depositing their data and collaborating with other groups. DBCollHIV allows investigators to manipulate their own datasets, as well as integrating molecular and clinical HIV data, in an innovative fashion.  相似文献   
54.
Bone marrow cells (BMCs) are the main type of cells used for transplantation therapies. Obesity, a major world health problem, has been demonstrated to affect various tissues, including bone marrow. This could compromise the success of such therapies. One of the main mechanisms underlying the pathogenesis of obesity is mitochondrial dysfunction, and recent data have suggested an important role for mitochondrial metabolism in the regulation of stem cell proliferation and differentiation. Since the potential use of BMCs for clinical therapies depends on their viability and capacity to proliferate and/or differentiate properly, the analysis of mitochondrial function and cell viability could be important approaches for evaluating BMC quality in the context of obesity. We therefore compared BMCs from a control group (CG) and an obese group (OG) of mice and evaluated their mitochondrial function, proliferation capacity, apoptosis, and levels of proteins involved in energy metabolism. BMCs from OG had increased apoptosis and decreased proliferation rates compared with CG. Mitochondrial respiratory capacity, biogenesis, and the coupling between oxidative phosphorylation and ATP synthesis were significantly decreased in OG compared with CG, in correlation with increased levels of uncoupling protein 2 and reduced peroxisome proliferator-activated receptor-coactivator 1α content. OG also had decreased amounts of the glucose transporter GLUT-1 and insulin receptor (IRβ). Thus, Western-diet-induced obesity leads to mitochondrial dysfunction and reduced proliferative capacity in BMCs, changes that, in turn, might compromise the success of therapies utilizing these cells.  相似文献   
55.

Background

HIV-1-infected individuals who spontaneously control viral replication represent an example of successful containment of the AIDS virus. Understanding the anti-viral immune responses in these individuals may help in vaccine design. However, immune responses against HIV-1 are normally analyzed using HIV-1 consensus B 15-mers that overlap by 11 amino acids. Unfortunately, this method may underestimate the real breadth of the cellular immune responses against the autologous sequence of the infecting virus.

Methodology and Principal Findings

Here we compared cellular immune responses against nef and vif-encoded consensus B 15-mer peptides to responses against HLA class I-predicted minimal optimal epitopes from consensus B and autologous sequences in six patients who have controlled HIV-1 replication. Interestingly, our analysis revealed that three of our patients had broader cellular immune responses against HLA class I-predicted minimal optimal epitopes from either autologous viruses or from the HIV-1 consensus B sequence, when compared to responses against the 15-mer HIV-1 type B consensus peptides.

Conclusion and Significance

This suggests that the cellular immune responses against HIV-1 in controller patients may be broader than we had previously anticipated.  相似文献   
56.
The complex salt named Prussian Blue, Fe4[Fe(CN)6]3?15 H2O, can release cyanide at pH>10. From the point of view of the origin of life, this fact is of interest, since the oligomers of HCN, formed in the presence of ammonium or amines, leads to a variety of biomolecules. In this work, for the first time, the thermal wet decomposition of Prussian Blue was studied. To establish the influence of temperature and reaction time on the ability of Prussian Blue to release cyanide and to subsequently generate other compounds, suspensions of Prussian Blue were heated at temperatures from room temperature to 150° at pH 12 in NH3 environment for several days. The NH3 wet decomposition of Prussian Blue generated hematite, α‐Fe2O3, the soluble complex salt (NH4)4[Fe(CN6)]?1.5 H2O, and several organic compounds, the nature and yield of which depend on the experimental conditions. Urea, lactic acid, 5,5‐dimethylhydantoin, and several amino acids and carboxylic acids were identified by their trimethylsilyl (TMS) derivatives. HCN, cyanogen (C2N2), and formamide (HCONH2) were detected in the gas phase by GC/MS analysis.  相似文献   
57.
LASSBio-581 is a N-phenylpiperazine derivative designed for the treatment of schizophrenia. In this study, four strains of filamentous fungi were screened for their capabilities to biotransform LASSBio-581. Cunninghamella echinulata ATCC 9244 was chosen to scale up the biosynthesis of the p-hydroxylated metabolite of LASSBio-581. The chemical structure of the metabolite was confirmed by NMR, LC–MS and X-ray crystallography. Binding studies performed on brain homogenate indicated that the p-hydroxylated metabolite can be considered more selective for dopamine receptors than LASSBio-581, and, therefore, can be used to design new selective dopamine inhibitors.  相似文献   
58.
59.
In continuing our screening program of naphthoquinone activity against Trypanosoma cruzi, the aetiological agent of Chagas’ disease, new β-lapachone-based 1,2,3-triazoles, 3-arylamino-nor-β-lapachones, 3-alkoxy-nor-β-lapachones and imidazole anthraquinones were synthesised and evaluated against bloodstream trypomastigote forms of the parasite. Compounds 2,2-dimethyl-3-(2,4-dibromophenylamino)-2,3-dihydro-naphtho[1,2-b]furan-4,5-dione, IC50/24 h 24.9 ± 7.4 and 4-azido-3-bromo-2,2-dimethyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione with 23.4 ± 3.8 μM showed a trypanosomicidal activity higher than benznidazole. These results demonstrate the potential of naphthoquinone derivatives as novel structures for the development of alternative drugs for Chagas’ disease.  相似文献   
60.
Plant allelochemicals are nonnutritional chemicals that interfere with the biology of herbivores. We posed the hypothesis that ingestion of a glycoalkaloid allelochemical, α‐solanine, impairs biological parameters of greater wax moths Galleria mellonella. To test this idea, we reared wax moths on artificial diets with 0.015, 0.15, or 1.5 mg/100 g diet of α‐solanine. Addition of α‐solanine to the diet affected survival of seventh‐instar larvae, pupae, and adults; and female fecundity and fertility. The diet containing the highest α‐solanine concentration led to decreased survivorship, fecundity, and fertility. The diets supplemented with α‐solanine led to increased malondialdehyde and protein carbonyl contents in midgut and fat body and the effect was dose‐dependent. Dietary α‐solanine led to increased midgut glutathione S‐transferase activity and to decreased fat body glutathione S‐transferase activitiy. We infer from these findings that α‐solanine influences life history parameters and antioxidative enzyme activities in the midgut and fat body of G. mellonella.  相似文献   
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