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1.
Curcumin has a plethora of biological properties, making this compound potentially effective in the treatment of several diseases, including cancer. However, curcumin clinical use is compromised by its poor pharmacokinetics, being crucial to find novel analogs with better pharmacokinetic and pharmacological properties. Here, we aimed to evaluate the stability, bioavailability and pharmacokinetic profiles of monocarbonyl analogs of curcumin. A small library of monocarbonyl analogs of curcumin 1a–q was synthesized. Lipophilicity and stability in physiological conditions were both assessed by HPLC-UV, while two different methods assessed the electrophilic character of each compound monitored by NMR and by UV-spectroscopy. The potential therapeutic effect of the analogs 1a–q was evaluated in human colon carcinoma cells and toxicity in immortalized hepatocytes. Our results showed that the curcumin analog 1e is a promising agent against colorectal cancer, with improved stability and efficacy/safety profile.  相似文献   
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Fifty-two amoebic liver abscess cases were assessed for the release of lymphokines (LMIF) using detergent dissected membrane proteins (DDMP) of axenic Entamoeba histolytica (NIH:200) obtained with sodium deoxycholate treatment. Lymphokines release by T lymphocytes in response to both DDMP and whole amoebic lysate (WAL) was tested by leukocyte migration inhibition test on blood samples from amoebic liver abscess cases. A significant increase was noted in the release of LMIF and 100% positivity was observed with DDMP compared to whole amoebic extract with a positivity of 73%. The difference between means of the above two with regards to release of LMIF was found to be highly significant (P less than 0.005). This shows the patients had high degree of leukocyte sensitization to surface antigens of E. histolytica compared to the whole amoebic lysate. These findings suggest that the antigens shed might have important role as a potent antigen in elicitation of CMI response in amoebic liver abscess cases.  相似文献   
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Introduction

Adipokines such as adiponectin, leptin, and visfatin/nicotinamide phosphoribosyltransferase (NAMPT) have recently emerged as pro-inflammatory mediators involved in the pathophysiology of rheumatoid arthritis (RA). We aimed to determine whether serum adipokine levels independently predicted early radiographic disease progression in early RA.

Methods

In total, 791 patients were included from the prospective Etude et Suivi des POlyarthrites Indifférenciées Récentes (ESPOIR) cohort who met the American College of Rheumatology-European League Against Rheumatism criteria for RA (n = 632) or had undifferentiated arthritis (UA) (n = 159). Enzyme-linked immunosorbent assay (ELISA) was used to assess baseline serum levels of adiponectin, leptin, and visfatin/NAMPT. In the RA group, we tested the association of serum adipokine levels and (a) baseline radiographic damage and (b) radiographic disease progression, defined as a change >0 or ≥5 in total Sharp-van der Heijde Score (∆SHS) between inclusion and 1 year (∆SHS ≥1 or rapid radiographic progression: ∆SHS ≥5), adjusting for confounders (age, sex, body-mass index, insulin resistance, C-reactive protein level, Disease Activity Score in 28 joints, Health Assessment Questionnaire score, autoantibody status, steroid use, and radiographic evidence of RA damage at inclusion).

Results

Adiponectin level was independently associated with baseline total SHS (adjusted β = 0.12; P = 0.006). It was also associated with ∆SHS ≥1 (adjusted odds ratio (aOR) = 1.84 (1.25 to 2.72)) involving erosive as well as narrowing disease progression (aOR = 1.73 (1.17 to 2.55) and 1.93 (1.04 to 3.57), respectively). Serum adiponectin level predicted ∆SHS ≥5 (aOR = 2.0 (1.14 to 3.52)). Serum leptin level was independently associated only with ∆SHS >0 (aOR = 1.59 (1.05 to 2.42)). Conversely, serum visfatin/NAMPT level and radiographic disease progression were unrelated. Considering the receiver-operated characteristic curves, the best adiponectin cut-offs were 4.14 μg/ml for ∆SHS ≥1 and 6.04 μg/ml for ∆SHS ≥5, with a good specificity (58% and 75% for ∆SHS ≥1 and ∆SHS ≥5, respectively) and high negative predictive values (75% and 92% for ∆SHS ≥1 or ∆SHS ≥5, respectively).

Conclusion

Serum adiponectin level is a simple useful biomarker associated with early radiographic disease progression in early RA, independent of RA-confounding factors and metabolic status.  相似文献   
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Biological Trace Element Research - This report explains the employing of a combination test of traditional cell culture with a quantitative real-time PCR for assessment of the antiviral effect of...  相似文献   
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The changes in lipid composition enable the micro-organisms to maintain membrane functions in the face of environmental fluctuations. The relationship between membrane fatty acid composition and UV-C stress was determined for mid-exponential phase and stationary phase Pseudomonas aeruginosa. The total lipids were obtained by dichloromethane/methanol (3:1) and were quantified by GC. The TLC analysis of phospholipids showed the presence of three major fractions phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. Significant modifications, as manifested by an increase of UFA, were obtained. Interestingly, this microorganism showed a remarkable capacity for recovery from the stressful effects of UV-C.  相似文献   
7.
The detection of P53 alteration by serological method is easier to perform, does not require tumor tissues and is of interest for patients monitoring. In this study, we described the development of a home made ELISA test based on recombinant human P53 protein produced in Pichia pastoris and used as antigen for the detection of serum p53-Abs in colorectal carcinoma patients. The human P53 was secreted as a His-tagged protein by recombinant KM71 strain (Kα21) via the peptide signal α of the Saccharomyces cerevisiae mating type gene. The recombinant P53-His was able to detect p53-Abs in 23.4 % of patients. Serum p53-Abs correlated significantly with surgical treatment (P = 0.007), relapse during follow-up (P = 0.036), depth of invasion (P = 0.036) and the level of CA19-9 (P = 0.034). Survival analysis showed that patients negative for serum p53-Abs exhibited a prolonged disease free survival period (P log rank = 0.012). In conclusion, the secreted recombinant human P53-His produced in P. pastoris seems to be a useful antigen for detection of serum p53 Abs in patients with colorectal carcinoma.  相似文献   
8.
Diploid wheat, Triticum monococcum L. (einkorn) is an ideal plant material for wheat functional genomics. Brittle culm mutant was identified by screening of the ethyl methane sulphonate-treated M 2 progenies of a T. monococcum accession pau14087 by banding the plant parts manually. The brittle culm mutant with drooping leaves, early flowering, reduced tiller numbers and susceptible to lodging had also exhibited brittleness in all plant parts than the wild-type parents. Comprehensive mechanical strength, histological, biochemical, scanning electron microscopy, and Fourier transform infrared spectroscopy analyses of brittle culm mutant supplemented and complemented the findings that the mutant had defective cellulose biosynthesis pathway and deposition of cell wall materials on secondary cell wall of mechanical tissues. Microscopic studies demonstrated that the decrease in cellulose contents resulted in the irregular cell wall organization in xylem vessels of leaf vascular bundles. To map the brc5 mutant, mapping populations were developed by crossing the brittle culm mutant with wild Triticum boeoticum acc. pau5088, having non-brittle characters. The brittle culm mutation was mapped between SSR markers, Xcfd39 and Xgwm126 on 5AmL chromosome of T. monococcum, with genetic distances of 2.6 and 4.8 cM, respectively. The brc5 mutant mapped on 5AmL, being distinct from a previously mapped brittle culm mutant in wheat, has been designated as brc5. The work on fine mapping and map-based cloning of brc5 gene regulating synthesis and deposition of cellulose on the secondary cell wall is in progress.  相似文献   
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Staphylococcus aureus is a gram positive bacterium, responsible for both community-acquired and hospital-acquired infection, resulting in a mortality rate of 39%. 43.2% resistance to methicilin and emerging resistance to Fluroquinolone and Oxazolidinone, have evoked the necessity of the establishment of alternative and effective therapeutic approach to treat this bacteria. In this computational study, various database and online software are used to determine some specific targets of Staphylococcus aureus N315 other than those used by Penicillin, Quinolone and Oxazolidinone. For this purpose, among 302 essential proteins, 101 nonhomologous proteins were accrued and 64 proteins which are unique in several metabolic pathways of S. aureus were isolated by using metabolic pathway analysis tools. Furthermore, 7 essentially unique enzymes involved in exclusive metabolic pathways were revealed by this research, which can be potential drug target. Along with these important enzymes, 15 non-homologous proteins located on membrane were identified, which can play a vital role as potential therapeutic targets for the future researchers.  相似文献   
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