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Objectives

To evaluate the chemopreventive efficacy of Diclofenac, a preferential cyclooxygenase-2 (COX-2) inhibiting non steroidal anti-inflammatory drug (NSAID) in the 9, 10 Dimethylbenz(a)anthracene (DMBA) induced experimental lung carcinogenesis.

Methods

Animals were divided into 4 groups. Control group received normal saline intratratracheally. DMBA group was given DMBA (20 mg/kg of body weight) in the similar manner. DMBA + Diclofenac group was given daily oral dose of Diclofenac (8 mg/kg of body weight) in addition to DMBA while the last group received Diclofenac only. Animals were sacrificed after 24 weeks. COX-2 expression was studied by immunohistochemistry (IHC) and Western immunoblotting. For apoptosis study DNA fragmentation on agarose gel and florescent staining of alveolar macrophages were done.

Results

The incidence and burden of tumor were reduced by the Diclofenac treatment. Diclofenac caused the reduction in the COX-2 levels which were increased in the DMBA treated group. It also caused the induction of apoptosis as seen by both techniques.

Conclusion

From all these results it can be concluded that Diclofenac might have a chemopreventive role for lung carcinogenesis which is mediated by suppression of COX-2 enzyme and induction of apoptosis.  相似文献   

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Mu R  Romero TA  Hanley KA  Dawe AL 《Virus research》2011,161(2):203-208
Virulence-attenuating viruses (hypoviruses) of the filamentous fungus Cryphonectria parasitica, the causative agent of chestnut blight, have become a premier model for understanding the molecular biology of mycoviruses. However, a major gap exists in current understanding of structure and function of the untranslated regions (UTRs) of the hypovirus RNA genome, despite considerable evidence that secondary and tertiary UTR structure plays a crucial role in the control of translation and genome replication in other systems. In this study we have used structure prediction software coupled with RNase digestion studies to develop validated structural models for the 5′ UTRs of the two best-characterized members of the Hypoviridae, CHV1-EP713 and CHV1-Euro7. These two hypovirus strains exhibit significant variation in virulence attenuation despite sharing >90% sequence identity. Our models reveal highly structured regions in the 5′ UTR of both strains, with numerous stem-loops suggestive of internal ribosome entry sites. However, considerable differences in the size and complexity of structural elements exist between the two strains. These data will guide future, mutagenesis-based studies of the structural requirements for hypovirus genome replication and translation.  相似文献   

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Mitoxantrone is one of the few FDA-approved drugs available to treat rapidly progressing forms of multiple sclerosis; however, its utilization is compromised by a cardiotoxic potential and the risk of mitoxantrone-induced leukemia. BBR3378, a novel aza-anthrapyrazole, is structurally similar to mitoxantrone, but lacks the ring hydroxyls that may contribute to cardiotoxicity. Here, we investigated the therapeutic activity of BBR3378 in a C57BL/6 mouse model of multiple sclerosis. Mice given BBR3378, before or after the priming and expansion of MOG-specific responses, were protected from ascending paralysis. Strikingly, two doses of BBR3378 given a week after EAE induction were sufficient to provide significant protection from clinical symptoms and reduce MOG-specific proinflammatory T cell cytokine production, and serum IgG responses. Furthermore, while mitoxantrone is associated with persistent lymphopenia and cardiotoxicity, no such outcomes were detected in BBR3378-treated mice. Our findings show that BBR3378 can ameliorate encephalitogenic mechanisms in EAE and antagonize underlying autoimmune mechanisms.  相似文献   

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The scope of receptor editing and its association with autoimmunity   总被引:6,自引:0,他引:6  
Random assembly of antibody variable (V), diversity (D) and joining (J) gene segments creates a vast repertoire of antigen receptors, including autoreactive ones. Three ways that are known to reduce autoreactivity in the B-cell compartment include clonal deletion, functional inactivation and receptor editing, a mechanism involving a change in antigen receptor specificity through continued V(D)J recombination. New data suggest that editing can efficiently eliminate autoreactivity, yet, in an autoimmune context, secondary antibody gene rearrangements might also contribute to autoimmunity.  相似文献   

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In a study of 523 normal subjects of differing ethnic groups, including 189 South American Indians, we have described novel hybridization patterns corresponding to 22 potentially new HLA-B locus alleles. Three of these alleles were subtypes of B35. The locally assigned alleles, B-3504v, B-3505v, and B-3508v have been sequenced and were officially designated as B*3512, B*3517, and B*3518, respectively. In addition, we determined the nucleotide sequence of another new variant, locally designated B-3509.2. B*3517, was found in 3 individuals (2 Hispanic, 1 Caucasian), it differs from B*3505 by 3 nucleotide substitutions that lead to changes in residues 94, 95, and 103. B*3517 differs from B*3501 in residues 97 and 103. B*3518 was found in 7 South American Indian individuals (6 of 124 Toba Indians, 1 of 18 Pilaga Indians). It differs from B*3509 by 2 silent nucleotide substitutions and by one nonsynonymous substitution in codon 156 (Arg → Leu). B*3512 differs from B*3504 by 3 nucleotides, one of them leading to a substitution in residue 103 (Val → Leu). B*3509 was observed in 3 individuals from the Wichi tribe. The nucleotide sequence of one of these was determined and was found to differ from B*35091 by two synonymous nucleotide substitutions.

The distinguishing amino acid substitutions in residues 95, 97, and 156 contribute to the structure of specificity pockets F, C, and E, and D and E respectively; therefore, it is possible that some of the new alleles may have different peptide binding profiles. It has been shown that differences at residue 156 may elicit different allorecognition and mediate graft-versus-host disease and rejection in bone marrow transplantation. The mechanisms for the generation of these novel alleles may involve gene conversion events in which short exon-3 segments from the common Native American alleles B*4002 or B*4801 were inserted in HLA-B35 backbone structures. The novel allele B*3518 is closely related to B*35092 and to B*3508. Two alternative hypotheses for its generation can be suggested, the most plausible one would involve B*35092, the putative progenitor of B*3518, since both alleles are prevalent in the same Indian tribes.  相似文献   


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Inhaled corticosteroids are the mainstay of treatment for persistent asthma because of their proven efficacy, which is better than any other class of antiasthma therapy. Concerns about unwanted systemic effects with long-term use has, however, limited their use. Efforts have been made to develop inhaled corticosteroids with less systemic activity for a given clinical effect, thereby improving their therapeutic index. Many different study designs and outcome variables have been used to compare different inhaled corticosteroids. Differences in pharmacologic properties between drugs are most easily and accurately measured and quantified by measures of systemic effects. However, these differences should always be related to differences in clinical effects. It is difficult to draw firm conclusions with respect to the therapeutic index of different inhaled corticosteroids because no direct placebo-controlled, dose-response comparisons of clinical effects have been made. Despite this caveat, the available studies suggest that microgram for microgram, when delivered by a pressurized metered-dose inhaler (pMDI), fluticasone propionate (FP) is more effective than beclomethasone dipropionate (BDP), triamcinolone acetonide (TAA), or budesonide; however, the efficacy of budesonide delivered by Turbuhaler is equipotent to that of FP delivered by pMDI or Diskhaler and more effective than that of BDP. When comparative safety is considered, budesonide or TAA delivered by pMDI have less systemic activity than FP delivered by pMDI, whereas BDP and FP delivered by pMDI appear to be equivalent. Also, budesonide delivered by Turbuhaler has less systemic activity than FP delivered by Diskhaler. (J Allergy Clin Immunol 1998;102:879-86.)  相似文献   

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Leucine and protein metabolism in rats with chronic renal insufficiency   总被引:2,自引:0,他引:2  
The aim of this study was to evaluate the effect of chronic uremia induced by 5/6 nephrectomy (5/6NX) on changes in protein and branched-chain amino acid (BCAA; valine, leucine and isoleucine) metabolism. The control group consisted of sham operated rats. Twenty eight weeks after surgery the parameters of protein and amino acid metabolism were evaluated using a primed constant intravenous infusion of L-[1-(14)C]leucine. A drop in BCAA levels and a significant increase in urea, creatinine and cholesterol were observed in plasma of all 5/6NX rats. However, severe uremia with acidosis developed only in one third of rats with 5/6NX. In 5/6NX rats with acidosis significant increases in proteolysis, leucine oxidation, leucine oxidized fraction, and leucine clearance were observed in comparison with the control group and rats with 5/6NX without acidosis. In addition, in 5/6NX rats with acidosis a significant decrease in valine concentration in gastrocnemius muscle was found. We conclude that marked activation of proteolysis occurs in severe chronic renal failure and is probably caused by metabolic changes related to acidosis development.  相似文献   

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The association of HLA-DRB1 and DQB1 genes with IDDM in Koreans was assessed using 115 IDDM patients and 140 nondiabetic controls. DQB1*0201 is the only DQB1 allele positively associated with IDDM while DQB1*0602, *0601 and *0301 are negatively associated. Three DRB1 alleles (DRB1*0301, DRB1*0407 and DRB1*0901) are positively associated while four DR allele groups (DRB1*15, DRB1*12, DRB1*10 and DRB1*14) are negatively associated. However, Haplotype analyses indicated that DQB1*0302, DRB1*0405 and DRB1*0401 may confer susceptibility because the DRB1*0405-DQB1*0302 and DRB1*0401-DQB1*0302 haplotypes are positively associated with the disease. The lack of association in Koreans with the DQB1*0302 allele, which appears predisposing in studies of non-Orientals, is due to its strong linkage disequilibrium (LD) with the protective DRB1*0403 and *0406 alleles, while the lack of association with DRB1*0405 is because of its strong LD with the protective DQB1*0401 allele. Nine DR/DQ genotypes confer significantly increased risk to IDDM. Seven of the nine genotypes (DR3/4s, DR1/4s, DR4s/13, DR4s/8, DR4s/7, DR9/13 and DR3/9) were also found to be at high risk to IDDM in other populations, while the two others (DR1/9 and DR9/9) are only found in Koreans. Surprisingly, DR4/4 homozygotes are not associated with high risk to IDDM in Koreans. This observation can be explained by the high frequency of protective DR4 subtypes and the protective DQ alleles (0301 and 0401) associated with the susceptible DR4 alleles. Our analyses indicate that the counterbalancing act between susceptible DRB1 and protective DQB1, and vice versa, that has already been observed in Chinese and Japanese, is the major factor responsible for the low incidence of diabetes in Koreans.  相似文献   

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The potentially harmful effects of short-term mechanical ventilation during surgery have been examined in recent years. An optimal strategy for mechanical ventilation of patients during non-laparoscopic abdominal surgery must be devised. A total of 63 patients undergoing elective open abdominal surgery with more than 2 h of ventilation time were selected for this randomized, open-label, clinical study. They were divided into three ventilation groups: high volume of 9 ml/kg IBW (ideal body weight) with ZEEP (zero end-expiratory pressure); low volume of 7 ml/kg IBW with 8 cm H2O PEEP (positive end expiratory pressure); and low volume of 7 ml/kg IBW with 8 cm H2O PEEP and recruitment. Intraoperative PaO2/FiO2 ratio and pulmonary compliance and postoperative pulmonary function were measured. There were no significant differences in intraoperative PaO2/FiO2 ratio among the three groups (P=0.31). The pulmonary compliance of three groups showed different changes over time (group effect over time P=0.0006). There were no significant differences in FEV1 or FVC among the three groups (P=0.32 and 0.09, respectively), but both of these measurements showed different changes over time (group effect over time P<0.001). On the first postoperative day, the low volume with high PEEP and recruitment group had significantly higher FEV1 than the other two groups (mean ± SD): 1.52±0.37 versus 0.95±0.38 (P<0.001) and 1.52±0.37 versus 0.95±0.34 (P<0.001), respectively. Low tidal volume with PEEP and recruitment showed advantages in maintaining the pulmonary compliance and expediting the recovery of the 1st postoperative day’s pulmonary function in patients undergoing non-laparoscopic abdominal surgery.  相似文献   

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The emergence of oseltamivir resistance in seasonal and pandemic influenza A/H1N1 has created challenges for diagnosis and clinical management. This review discusses how clinical virology laboratories have handled diagnosis of oseltamivir-resistant H1N1 and what we have learned from clinical studies and case series. Immunocompetent patients infected with oseltamivir-resistant H1N1 have similar outcomes as patients infected with oseltamivir-susceptible H1N1. However, immunocompromised patients infected with oseltamivir-resistant H1N1 experience potentially more risks of complication and transmissibility with few therapeutic options.  相似文献   

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