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1.
alpha 1-Acid glycoprotein (AGP) was purified to homogeneity by a 3-step procedure using pseudo-ligand affinity chromatography on immobilized Cibacron blue F3GA, Procion red HE3B, and preparative column isoelectric focusing. The overall yield of the combined techniques was 88%. Analysis of the purified AGP by lectin affinity chromatography on immobilized Con A and immunoaffino-electrophoresis indicated that the most acidic form did not interact with the lectin, while the two more basic fractions possessed different affinities for Con A. In addition, 3 different populations of AGP were clearly separated by Con A affinity chromatography.  相似文献   
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Thiosemicarbazones have become one of the promising compounds as new clinical candidates due to their wide spectrum of pharmaceutical activities. The wide range of their biological activities depends generally on their related aldehyde or ketone groups. Here, we report the pharmacological activities of some thiosemicarbazones synthesized in this work. Benzophenone and derivatives were used with N(4)-phenyl-3-thiosemicarbazide to synthesize corresponding five thiosemicarbazones (1–5). Their structures were characterized by spectrometrical methods analysis IR, NMR 1H & 13C and MS. The compounds were then screened in vitro for their antiparasitic activity and toxicity on Trypanosoma brucei brucei and Artemia salina Leach respectively. The selectivity index of each compound was also determined. Four thiosemicarbazones such as 4, 2, 3 and 1 reveal interesting trypanocidal activities with their half inhibitory concentration (IC50) equal to 2.76, 2.83, 3.86 and 8.48 μM respectively, while compound 5 (IC50 = 12.16 μM) showed a moderate anti-trypanosomal activity on parasite. In toxicity test, except compound 1, which showed a half lethal concentration LC50 >281 μM, the others exerted toxic effect on larvae with LC50 of 5.56, 13.62, 14.55 and 42.50 μM respectively for thiosemicarbazones 4, 5, 3 and 2. In agreement to their selectivity index, which is greater than 1 (SI >1), these compounds clearly displayed significant selective pharmaceutical activities on the parasite tested. The thiosemicarbazones 2–5 that displayed significant anti-trypanosomal and cytoxicity activities are suggested to have anti-neoplastic and anti-cancer activities.  相似文献   
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Human Genetics - Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). Analysis of DNA from a pancreatic sufficient patient by means of...  相似文献   
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Deep-sea hydrothermal vents are inhabited by complex communities of microbes and their viruses. Despite the importance of viruses in controlling the diversity, adaptation and evolution of their microbial hosts, to date, only eight bacterial and two archaeal viruses isolated from abyssal ecosystems have been described. Thus, our efforts focused on gaining new insights into viruses associated with deep-sea autotrophic archaea. Here, we provide the first evidence of an infection of hyperthermophilic methanogenic archaea by a head-tailed virus, Methanocaldococcus fervens tailed virus 1 (MFTV1). MFTV1 has an isometric head of 50 nm in diameter and a 150 nm-long non-contractile tail. Virions are released continuously without causing a sudden drop in host growth. MFTV1 infects Methanocaldococcus species and is the first hyperthermophilic head-tailed virus described thus far. The viral genome is a double-stranded linear DNA of 31 kb. Interestingly, our results suggest potential strategies adopted by the plasmid pMEFER01, carried by M. fervens, to spread horizontally in hyperthermophilic methanogens. The data presented here open a new window of understanding on how the abyssal mobilome interacts with hyperthermophilic marine archaea.  相似文献   
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Background

Bronchiectasis is defined as a permanent dilation of the airways arising from chronic bronchial inflammation/infection. In 50% of cases, no etiology can be identified. Recently, the role of the epithelial sodium channel ENaC has been pointed out in the pathophysiology of cystic fibrosis, a disease due to mutations in the CFTR gene and causing bronchiectasis in the airways. Moreover, it was found that transgenic mice overexpressing ENaCβ present cystic fibrosis-like lung disease symptoms. Our aim was to evaluate if a defective ENaC protein could be involved in the development of bronchiectasis.

Methods

We extensively analysed ENaCβ and γ genes in 55 patients with idiopathic bronchiectasis and without two mutations in the coding regions of CFTR. Thirty-eight patients presented functional abnormalities suggesting impaired sodium transport (abnormal sweat chloride concentration or nasal potential difference measurement), and 17 had no such evidence.

Results

Sequencing of the exons and flanking introns of the ENaCβ and γ gene identified five different amino-acid changes (p.Ser82Cys, p.Pro369Thr, p.Asn288Ser in ENaCβ ; and p.Gly183Ser, p.Glu197Lys in ENaCγ) in heterozygous state in 8 patients. The p.Ser82Cys amino-acid change was found in 3 unrelated patients who were also heterozygous for a CFTR mutation or variant (1 p.F508del, 1 IVS8-5T, and 1 IVS8-5T:1716G>A (p.E528E)). The other mutations were found in patients without CFTR mutation, the p.Glu197Lys mutation in 2 patients and the other variants in single patients. Among the 8 patients bearing an ENaC mutation, 5 had functional abnormalities suggesting impaired sodium transport.

Conclusion

Our results suggest that several variants in ENaCβ and γ genes might be deleterious for ENaC function and lead to bronchiectasis, especially in patients who are trans-heterozygotes for ENaCβ/CFTR mutations or variants.  相似文献   
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The spectrum of cystic fibrosis (CF) mutations in the North African population remains poorly known. In order to offer an effective diagnostic service and to determine accurate risk estimates, we decided to identify the CF mutations in 10 Algerian CF families. We carried out a chemical-clamp denaturing gradient gel electrophoresis analysis of the CFTR gene and automated direct DNA sequencing. We identified 5 mutations and we characterized 60% of the CF chromosomes. Taking advantage of the homogeneity of the sample, we report clinical features of homozygous CF patients.  相似文献   
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Treatment of rheumatoid arthritis (RA) with infliximab (Remicade) has been associated with the induction of antinuclear autoantibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) autoantibodies. In the present study we investigated the humoral immune response induced by infliximab against organ-specific or non-organ-specific antigens not only in RA patients but also in patients with ankylosing spondylitis (AS) during a two-year followup. The association between the presence of autoantibodies and clinical manifestations was then examined. The occurrence of the various autoantibodies was analyzed in 24 RA and 15 AS patients all treated with infliximab and in 30 RA patients receiving methotrexate but not infliximab, using the appropriate methods of detection. Infliximab led to a significant induction of ANA and anti-dsDNA autoantibodies in 86.7% and 57% of RA patients and in 85% and 31% of AS patients, respectively. The incidence of antiphospholipid (aPL) autoantibodies was significantly higher in both RA patients (21%) and AS patients (27%) than in the control group. Most anti-dsDNA and aPL autoantibodies were of IgM isotype and were not associated with infusion side effects, lupus-like manifestations or infectious disease. No other autoantibodies were shown to be induced by the treatment. Our results confirmed the occurrence of ANA and anti-dsDNA autoantibodies and demonstrated that the induction of ANA, anti-dsDNA and aPL autoantibodies is related to infliximab treatment in both RA and AS, with no significant relationship to clinical manifestations.  相似文献   
10.
Cystic fibrosis (CF) is a genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Despite improvements in treatment, pulmonary disease still remains the primary cause of death among these patients. In order to introduce a normal CFTR gene copy into airway epithelial cells, adenoviral vectors (AV) have been developed. AV are known to induce an inflammatory reaction that limits transgene expression, and can be potentially harmful. No human study has clearly monitored simultaneously, systemic and local inflammatory reaction, during AV administration. We report here the levels of C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 receptor antagonist (IL-1Ra) in plasma and bronchoalveolar lavage fluid (BALF) from six cystic fibrosis patients receiving AV encoding CFTR (AdCFTR). AdCFTR was administered to three cohorts of two patients into the nose on day 0, at doses ranging from 105 to 4 x 108 plaque-forming units (pfu), followed, on day 1, by aerosolization of 107 to 5.4 x 108 pfu. In order to ensure that patients were in the best clinical condition, and to further attenuate the broncho-pulmonary inflammation secondary to bacterial infection, they received antibiotic therapy, two weeks prior to AdCFTR administration, until 9 to 11 days after. We found that antibiotics markedly decreased CRP, TNF-alpha, IL-6, IL-1Ra levels in blood. In BALF, antibiotics slightly decreased TNF-alpha levels but had no effect on IL-8 and IL-1Ra, while IL-6 levels increased. AdCFTR administration did not induce any systemic or local cytokine release. In both blood and BALF, CRP, IL-8, IL-1Ra, TNF-alpha decreased, while IL-6 levels increased between day -7 and day 3. One patient presented an asymptomatic increase of all parameters in the BALF on day 7. Twenty one days later, he displayed a clinical deterioration suggestive of an exacerbation. In conclusion, this study demonstrates that antibiotic administration tends to attenuate systemic but not local broncho-pulmonary inflammation in CF patients. In the setting of our study, AdCFTR administration did not induce cytokine release. Further studies are necessary to investigate other inflammatory markers and the mechanisms involved during AV-mediated gene transfer for a better understanding of the immune reaction, which continues to hamper the development of gene therapy for CF patients.  相似文献   
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