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21.
Interleukin-4 exerts anti-inflammatory effects through decreased macrophage production of tumor necrosis factor-alpha and interleukin-1 beta. We investigated genetic predisposition in the interleukin-4 response to coronary revascularization and studied the association between C-590T polymorphism, interleukin-4 levels, and outcome of surgery. DNA was obtained from 96 consecutive patients undergoing elective coronary revascularization. Patients were genotyped for interleukin-4 C-590T polymorphism using a sequence-specific primer polymerase chain reaction. Interleukin-4 levels were measured using an enzyme-linked immunosorbent assay in serum samples taken 3 hr postoperatively. The frequency of interleukin-4 C-590T genotypes CC, CT, and TT was 33.3%, 27.1%, and 39.6%, respectively. Patients with the TT genotype had significantly higher circulating levels of interleukin-4 (3.4 +/- 4.6 pg x mL(-1)) postoperatively compared to CC (2.5 +/- 0.1 pg x mL(-1)) and CT (2.7 +/- 0.5 pg x mL(-1)) genotypes. Interleukin-4 C-590T polymorphism is the main determinant of postoperative interleukin-4 levels. The TT genotype is the highest producer of interleukin-4. Neither the genotype nor the serum levels seem to play any role in recovery from coronary artery bypass surgery.  相似文献   
22.
Accurate assessment of malignancy in oral squamous cell carcinoma is essential to optimize treatment planning. To detect a biomarker related to malignant propensity in gingival squamous cell carcinoma (GSCC), quantitative gene expression analysis of tetraspanin family genes was conducted. In 73 cases of GSCC, total RNA was extracted from carcinoma tissues, and gene expression was analyzed by quantitative real time‐PCR. Six tetraspanin family genes (CD9, CD63, CD81, CD82, CD151, NAG‐2) were investigated. Housekeeping genes (ACTB and GAPDH), anchor protein genes (JUP and PXN) and an integrin gene (ITGA3) were used as reference genes. Forty‐five gene expression ratios were calculated from these 11 gene expression levels and were analyzed with clinical parameters using multivariate statistical methods. According to the results of the logistic regression analysis subjecting cervical lymph node metastasis as a target variable, CD9/ACTB (p = 0.013) or CD9/CD82 (p = 0.013) in addition to tumor size (p = 0.028) were detected as significant factors. In Cox proportional hazards regression analysis, delayed cervical lymph node metastasis (p = 0.039) and tumor cell positive surgical margin (p = 0.032) in addition to CD151/GAPDH (p = 0.024) were detected as significant factors for death outcome. A Kaplan‐Meier survival curve presented a significantly lower survival rate of the group with a CD151/GAPDH value of 10 or more (log rank and generalized Wilcoxon tests: p = 0.0003). Results of this study present the usefulness of CD9 and CD151 expression levels as biomarkers for assessment of malignancy in GSCC. They also indicate that detection of residual tumor cells at the surgical margin and the biological malignancy of a tumor interdependently affects prognosis. © 2009 UICC  相似文献   
23.
Complex I deficiency is a frequent cause of mitochondrial disease as it accounts for one third of these disorders. By genotyping several putative disease loci using microsatellite markers we were able to describe a new NDUFS7 mutation in a consanguineous family with Leigh syndrome and isolated complex I deficiency. This mutation lies in the first intron of the NDUFS7 gene (c.17-1167 C>G) and creates a strong donor splice site resulting in the generation of a cryptic exon. This mutation is predicted to result in a shortened mutant protein of 41 instead of 213 amino acids containing only the first five amino acids of the normal protein. Analysis of the assembly state of the respiratory chain complexes under native condition revealed a marked decrease of fully assembled complex I while the quantity of the other complexes was not altered. These results report the first intronic NDUFS7 gene mutation and demonstrate the crucial role of NDUFS7 in the biogenesis of complex I.  相似文献   
24.
BACKGROUND & AIMS: Infliximab therapy is an effective approach to treating Crohn's disease. Development of antinuclear antibodies has been described in patients treated, but the size of the problem and the relationship with autoimmunity have not been investigated. We investigated the occurrence of antinuclear antibodies in 125 consecutive Crohn's disease patients and studied the relationship with symptoms of autoimmunity. METHODS: Autoantibodies and clinical data were investigated before and 1, 2, and 3 months after infliximab infusion. If antinuclear antibodies were > or =1:80, further study of double-stranded DNA, single-stranded DNA, histones, and ENA was performed. RESULTS: Cumulative antinuclear antibody incidence at 24 months was 71 of 125 (56.8%). Almost half of these patients developed antinuclear antibodies after the first infusion, and >75% became antinuclear antibody positive after fewer than 3 infusions. So far, only 15 of 71 patients have become seronegative, after a median of 12 months. Of 43 antinuclear antibody-positive patients who were further subtyped, 14 of 43 (32.6%) had double-stranded DNA, 17 (39.5%) had single-stranded DNA, 9 (20.9%) had antihistone, and 0% were ENA positive. Two patients (both antihistone and double-stranded DNA positive) developed drug-induced lupus without major organ damage, and 1 developed autoimmune hemolytic anemia. Antinuclear antibodies were associated with the female sex (odds ratio, 3.166; 95% confidence interval, 1.167-8.585; P = 0.024) and with papulosquamous or butterfly rash (odds ratio, 10.016; 95% confidence interval, 1.708-58.725; P = 0.011). CONCLUSIONS: The cumulative incidence of antinuclear antibodies was 56.8% after 24 months in this cohort of infliximab-treated Crohn's disease patients. Antinuclear antibodies persisted up to 1 year after the last infusion, and only a few patients became seronegative. Two patients developed drug-induced lupus erythematosus. Antinuclear antibodies were associated with the female sex and skin manifestations.  相似文献   
25.
Upper gastrointestinal (GI) toxicity of non-steroidal anti-inflammatory drugs (NSAIDs) is well characterized. There is also documented data regarding their adverse effects on lower GI tract, like colonic strictures, inflammatory bowel disease and complications of diverticular disease in the form of abscess or perforation. But there are only two case reports published previously that show colonic perforation due to use of NSAIDs solely. We present here a case of colonic perforation induced by short-term use of slow release diclofenac in a young man. Colonic perforation should be considered as the possible diagnosis in patients with acute abdomen and NSAIDs to be one of the differentials if other possibilities are ruled out.  相似文献   
26.
BACKGROUND: Crohn's disease (CD) is associated with gut barrier dysfunction. Besides the baseline barrier defect, a subgroup of patients also expresses an intestinal barrier hyperresponsiveness to nonsteroidal anti-inflammatory drugs. We studied whether reducing inflammation and restoring gut barrier dysfunction with anti-tumor necrosis factor (TNF) antibody treatment also antagonizes the permeability increase by oral nonsteroidal anti-inflammatory drug intake in patients with CD. METHODS: Thirty-one healthy control subjects and 25 patients with active CD were studied. The 31 controls performed intestinal permeability testing for Cr-EDTA before (baseline) and after oral intake of indomethacin (50 + 75 mg). Twenty-five patients carried out a baseline and indomethacin-mediated permeability test before infliximab infusion. The patients repeated either the indomethacin test (12/25) or baseline and indomethacin tests (13/25), 1 month after this treatment. Intestinal permeability was studied by measurement of urinary excretion of Cr-EDTA after oral intake. RESULTS: Increased whole gut permeation before treatment (3.16%; interquartile range [IQR], 2.92-5.72) was restored to normal values (2.47%; IQR, 1.97-2.78) by anti-TNF treatment. Indomethacin increased whole gut permeability significantly more in patients with CD (before anti-TNF: 6.50%; IQR, 4.84-10.38; after anti-TNF: 5.50%; IQR, 3.97-10.09) compared with the healthy subjects (4.66%; IQR, 3.51-5.64). Eleven of 25 patients (44%) had an abnormal whole gut permeability response to indomethacin before anti-TNF, and 9 of them remained hyperresponsive after infusion, despite clinical remission. CONCLUSIONS: Although anti-TNF treatment suppresses inflammation and restores gut barrier function in patients with CD, it does not antagonize the barrier hyperresponsiveness to indomethacin. These data support the notion of an underlying intestinal mucosal barrier hyperresponsiveness in a subset of patients with CD, independent of inflammation.  相似文献   
27.
Infection with the bacterial pathogen Mycobacterium tuberculosis imposes an enormous burden on global public health. New antibiotics are urgently needed to combat the global tuberculosis pandemic; however, the development of new small molecules is hindered by a lack of validated drug targets. Here, we describe the identification of a 4,6-diaryl-5,7-dimethyl coumarin series that kills M. tuberculosis by inhibiting fatty acid degradation protein D32 (FadD32), an enzyme that is required for biosynthesis of cell-wall mycolic acids. These substituted coumarin inhibitors directly inhibit the acyl-acyl carrier protein synthetase activity of FadD32. They effectively block bacterial replication both in vitro and in animal models of tuberculosis, validating FadD32 as a target for antibiotic development that works in the same pathway as the established antibiotic isoniazid. Targeting new steps in well-validated biosynthetic pathways in antitubercular therapy is a powerful strategy that removes much of the usual uncertainty surrounding new targets and in vivo clinical efficacy, while circumventing existing resistance to established targets.Tuberculosis is one of the leading causes of death by infectious diseases worldwide, killing an estimated 2 million people annually (1). The emergence of multidrug resistant (MDR) and extensively drug resistant (XDR) strains of Mycobacterium tuberculosis has increased the threat that this disease poses to global public health. Despite a few recent successes (24), there are relatively few candidates in the drug development pipeline for tuberculosis. Although there is a substantial amount of genetic data defining essential genes in M. tuberculosis (5, 6), little is known about which of the approximately ∼600 predicted essential proteins are possible drug targets. To meet current and future therapeutic needs, the discovery and validation of new drug targets and novel chemical structures that target these proteins is a critical priority.Recent years have seen an enormous increase in efforts to discover new molecules with novel mechanisms using both whole-cell screening and mechanism-based biochemical approaches (7); however, progress in validating new targets has been slow. Although there are numerous reports of small molecules with activity against M. tuberculosis, target identification remains a significant challenge. Similarly, although many potential targets have been proposed based on genetic and biochemical experiments, chemical and biological validation that these targets can be inhibited by drug-like molecules with efficacy in vivo is for the most part lacking. There are very few reports of new molecules with new targets that are effective in vivo. Bedaquiline, a diarylquinoline that targets bacterial ATP synthase, was recently provisionally registered by the Food and Drug Administration and is the only candidate molecule in clinical trials that has both a clearly defined and novel target (4). Other compounds in clinical trials include PA824 and Delaminid, both of which have complex mechanisms and targets that have not been clearly defined, and Linezolid, a ribosomal inhibitor that has been repurposed for M. tuberculosis treatment (8, 9). Molecules that inhibit new targets and have demonstrated efficacy in animals, but are not yet in clinical trials, include Benzothiazinones that target decaprenylphosphoryl-β-d-ribose 2′-epimerase (DprE1) (2) and inhibitors of malate synthase, a glyoxylate shunt enzyme (10). In addition to their potential as drug candidates, these molecules are significant for having facilitated the identification of novel targets for further efforts geared toward drug discovery.Herein, we report the identification of a small molecule that kills M. tuberculosis by inhibiting FadD32, an enzyme required for mycolic acid biosynthesis, using an unbiased whole-cell screening approach. Although FadD32 is not targeted by any known drug, mycolic acid biosynthesis is one of the few well-validated pathways in antituberculosis drug development. Isoniazid (INH), a central component of the more effective antituberculosis treatment regimens, similarly targets mycolic acid biosynthesis through inhibition of InhA (11). Because resistance to INH is on the rise worldwide, with an estimated 13% of tuberculosis cases exhibiting resistance to this important drug, its long-term utility may be limited. As a result, significant effort has been directed toward identifying novel inhibitors of InhA (1214), including an effort by Glaxo-Smith Kline and the TB Alliance. Identification of a drug that targets the critical pathway of mycolic acid biosynthesis at a step that is distinct from InhA, thereby bypassing INH resistance, would have a major impact on treatment of MDR and XDR tuberculosis. Importantly, the FadD32 inhibitor we have identified has activity in animal models of tuberculosis that is comparable with that of INH.  相似文献   
28.
29.
Objectives of the study were to describe the frequency of acne in late adolescent and adult students and to evaluate psychosocial impact of the disease. It was a cross-sectional study conducted in four institutions, from June to August 2008. Questionnaires with Cardiff Acne Disability Index (CADI) were filled by 950 students. They were examined for presence and severity of acne. Age ranged from 17 to 28 years. Frequency of facial acne was 74.6%. Difference between the genders was not statistically significant. Mean ADI score was 2.67 + 5.35, and range was 0-13. The disease had a greater psychosocial impact on females as compared to males.  相似文献   
30.
A major issue in immunosuppressive biotherapy is the use of mesenchymal stem cells (MSCs) that harbor regulatory capacity. However, currently used bone marrow-derived MSCs (BM-MSCs) are short-lived and cannot assure long lasting immunoregulatory function both in vitro and in vivo. Consequently, we have generated MSCs from human induced pluripotent stem (IPS-MSCs) cells that share similar properties with embryonic stem cells (ES-MSCs). Herein, we compared the immunoregulatory properties of ES/IPS-MSCs with those of BM-MSCs and showed, for the first time, that IPS-derived MSCs display remarkable inhibition of NK-cell proliferation and cytolytic function in a similar way to ES-MSCs. Both MSCs disrupt NK-cell cytolytic machinery in the same fashion that BM-MSCs, by down-regulating the expression of different activation markers and ERK1/2 signaling, leading to an impairment to form immunologic synapses with target cells and, therefore, secretion of cytotoxic granules. In addition, they are more resistant than adult BM-MSCs to preactivated NK cells. IPS-MSCs could represent an attractive alternative source of immunoregulatory cells, and their capacity to impair NK-cell cytotoxicity constitutes a complex mechanism to prevent allograft rejection.  相似文献   
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