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121.
Blomberg P Eskandarpour M Xia S Sylvén C Islam KB 《Biochemical and biophysical research communications》2002,298(4):505-510
Gene transfer into muscle upon injection of plasmid DNA is feasible but occurs with low frequency. However, by using electroporation after injection of plasmid DNA into mouse muscle it has been demonstrated that gene expression can be increased more than 150-fold. In this communication, we have used this technique in combination with plasmids containing a tandem repeat of three 72-bp DNA elements from the SV40 enhancer to study gene expression. Our results show that the combination of electroporation and a plasmid vector carrying these DNA elements results in increased and more persistent gene expression of the luciferase reporter gene in BALB/c mouse muscle. At 14 days after gene delivery, the gene expression was 16-fold higher in muscles injected and electroporated with the plasmid carrying the SV40 enhancers than with control plasmid. We have also studied the effects of the vehicle in which the plasmid was delivered, and the DNase inhibitor aurintricarboxylic acid (ATA), on gene expression. By combining ATA with 150 mM sodium phosphate buffer we were able to obtain a 2-fold increase in gene expression compared to delivery of the plasmid in physiological saline. These results are of importance for the development of efficient delivery techniques for naked DNA. 相似文献
122.
Faruque SM Chowdhury N Khan R Hasan MR Nahar J Islam MJ Yamasaki S Ghosh AN Nair GB Sack DA 《Applied and environmental microbiology》2003,69(12):7028-7031
Shigella dysenteriae type 1 is the causative agent of the most severe form of bacillary dysentery, which occurs as epidemics in many developing countries. We isolated a bacteriophage from surface water samples from Bangladesh that specifically lyses strains of S. dysenteriae type 1. This phage, designated SF-9, belongs to the Podoviridae family and has a 41-kb double-stranded DNA genome. Further screening of water samples for the prevalence of the phage revealed 9 of 71 (12.6%) water samples which were positive for the phage. These water samples were also positive in PCR assays for one or more S. dysenteriae type 1-specific genes, including ipaBCD and stx1, and live S. dysenteriae type 1 was isolated from three phage-positive samples. The results of this study suggest that phage SF-9 may have epidemiological applications in tracing the presence of S. dysenteriae type 1 in environmental waters. 相似文献
123.
Kaur P Yousuf S Ansari MA Siddiqui A Ahmad AS Islam F 《Biological trace element research》2003,95(3):247-258
The effect of various doses of sodium tellurite (0.4, 0.8, and 2.0 mg/kg body weight, orally) on the activity of antioxidant
enzymes (glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and catalase) and content of glutathione and thiobarbituric acid reactive substances (TBARSs) in the cerebrum,
cerebellum, and brainstem of male albino mice was studied after 15 d of treatment. All of the doses of tellurium (0.4, 0.8,
and 2.0 mg/kg body weight, orally) have depleted the activity of antioxidant enzymes and the content of glutathione dose dependently
in the cerebrum, cerebellum, and brainstem and it was significant with the dose of 2.0 mg/kg. On the other hand, the 2.0-mg/kg
dose of tellurium has significantly elevated the content of TBARSs in the cerebrum and cerebellum. The 0.8-mg/kg dose of tellurium
has significantly depleted the activities of glutathione peroxidase in the cerebrum and brainstem, glutathione-S-transferase in the cerebrum and cerebellum, catalase in the brainstem, and the content of glutathione in the cerebrum and
cerebellum. In contrast, this dose has significantly elevated the content of TBARSs in the cerebrum and cerebellum. However,
the depletion in the activity of glutathione reductase with various doses of sodium tellurite was not significant in any brain
part of mice. The result suggests that sodium tellurite differentially affects the antioxidant status within various parts
of the mice brain. 相似文献
124.
Black AP Bhayani H Ryder CA Pugh MT Gardner-Medwin JM Southwood TR 《Arthritis research & therapy》2003,5(5):R277-R284
The aim of this research was to determine whether all memory T cells have the same propensity to migrate to the joint in patients
with juvenile idiopathic arthritis. Paired synovial fluid and peripheral blood mononuclear cell proliferative responses to
a panel of antigens were measured and the results correlated with a detailed set of laboratory and clinical data from 39 patients
with juvenile idiopathic arthritis. Two distinct patterns of proliferative response were found in the majority of patients:
a diverse pattern, in which synovial fluid responses were greater than peripheral blood responses for all antigens tested;
and a restricted pattern, in which peripheral blood responses to some antigens were more vigorous than those in the synovial
fluid compartment. The diverse pattern was generally found in patients with a high acute phase response, whereas patients
without elevated acute phase proteins were more likely to demonstrate a restricted pattern. We propose that an association
between the synovial fluid T cell repertoire and the acute phase response suggests that proinflammatory cytokines may influence
recruitment of memory T cells to an inflammatory site, independent of their antigen specificity. Additionally, increased responses
to enteric bacteria and the presence of αEβ7 T cells in synovial fluid may reflect accumulation of gut associated T cells
in the synovial compartment, even in the absence of an elevated acute phase response. This is the first report of an association
between the acute phase response and the T cell population recruited to an inflammatory site. 相似文献
125.
Phadke SM Islam K Deslouches B Kapoor SA Beer Stolz D Watkins SC Montelaro RC Pilewski JM Mietzner TA 《Peptides》2003,24(8):1099-1107
Lentivirus lytic peptides (LLPs) are derived from HIV-1 and have antibacterial properties. LLP derivatives (eLLPs) were engineered for greater potency against Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA). Minimum bactericidal concentration (MBC) was determined in low and physiologic salt concentrations. MBC was decreased against SA and equivalent against PA in physiologic salt when compared to the parent compound LLP1. In a novel cystic fibrosis (CF) airway cell model, one derivative, WLSA5, reduced the number of adherent PA and only moderately affected CF cell viability. Overall, eLLPs are selectively toxic to bacteria and may be useful against CF airway infections. 相似文献
126.
Sun Q Tafesse L Islam K Zhou X Victory SF Zhang C Hachicha M Schmid LA Patel A Rotshteyn Y Valenzano KJ Kyle DJ 《Bioorganic & medicinal chemistry letters》2003,13(20):3611-3616
A series of 4-(2-pyridyl)piperazine-1-carboxamide analogues based on the lead compound 1 was synthesized and evaluated for VR1 antagonist activity in capsaicin-induced (CAP) and pH (5.5)-induced (pH) FLIPR assays in a rat VR1-expressing HEK293 cell line. Potent VR1 antagonists were identified through SAR studies. From these studies, 18 was found to be very potent in the in vitro assay [IC(50)=4.8 nM (pH) and 35 nM (CAP)] and orally available in rat (F%=15.1). 相似文献
127.
Liang M Mallari C Rosser M Ng HP May K Monahan S Bauman JG Islam I Ghannam A Buckman B Shaw K Wei GP Xu W Zhao Z Ho E Shen J Oanh H Subramanyam B Vergona R Taub D Dunning L Harvey S Snider RM Hesselgesser J Morrissey MM Perez HD 《The Journal of biological chemistry》2000,275(25):19000-19008
The CC chemokine receptor-1 (CCR1) is a prime therapeutic target for treating autoimmune diseases. Through high capacity screening followed by chemical optimization, we identified a novel non-peptide CCR1 antagonist, R-N-[5-chloro-2-[2-[4-[(4-fluorophenyl)methyl]-2-methyl-1-piperazinyl ]-2-oxoethoxy]phenyl]urea hydrochloric acid salt (BX 471). Competition binding studies revealed that BX 471 was able to displace the CCR1 ligands macrophage inflammatory protein-1alpha (MIP-1alpha), RANTES, and monocyte chemotactic protein-3 (MCP-3) with high affinity (K(i) ranged from 1 nm to 5.5 nm). BX 471 was a potent functional antagonist based on its ability to inhibit a number of CCR1-mediated effects including Ca(2+) mobilization, increase in extracellular acidification rate, CD11b expression, and leukocyte migration. BX 471 demonstrated a greater than 10,000-fold selectivity for CCR1 compared with 28 G-protein-coupled receptors. Pharmacokinetic studies demonstrated that BX 471 was orally active with a bioavailability of 60% in dogs. Furthermore, BX 471 effectively reduces disease in a rat experimental allergic encephalomyelitis model of multiple sclerosis. This study is the first to demonstrate that a non-peptide chemokine receptor antagonist is efficacious in an animal model of an autoimmune disease. In summary, we have identified a potent, selective, and orally available CCR1 antagonist that may be useful in the treatment of chronic inflammatory diseases. 相似文献
128.
A sample of 871 currently married urban Bangladeshi women was used to assess the impact of mass media family planning programmes on current contraceptive use. The analyses suggested that radio had been playing a significant role in spreading family planning messages among eligible clients; 38% of women with access to a radio had heard of family planning messages while the figures for TV and newspaper were 18.5% and 8.5% respectively. Education, number of living children and current contraceptive use were important predictors of exposure to any mass media family planning messages. There was a negative relationship between breast-feeding and the current use of contraception indicating a low need for contraception among women who were breast-feeding. 相似文献
129.
Islam S Kim JB Trendel J Wheelock MJ Johnson KR 《Journal of cellular biochemistry》2000,78(1):141-150
Phenotypic changes resembling an epithelial-to-mesenchymal transition often occur as epithelial cells become tumorigenic. Two proteins that have been implicated in this process are vimentin and N-cadherin. In this study, we sought to establish a link between expression of vimentin and N-cadherin as oral squamous epithelial cells undergo a morphologic change resembling an epithelial-to-mesenchymal transition. We found that N-cadherin and vimentin did not influence the expression of one another. 相似文献
130.
Drosopoulos JH Broekman MJ Islam N Maliszewski CR Gayle RB Marcus AJ 《Biochemistry》2000,39(23):6936-6943
Endothelial cell CD39/ecto-ADPase plays a major role in vascular homeostasis. It rapidly metabolizes ADP released from stimulated platelets, thereby preventing further platelet activation and recruitment. We recently developed a recombinant, soluble form of human CD39, solCD39, with enzymatic and biological properties identical to CD39. To identify amino acids essential for enzymatic/biological activity, we performed site-directed mutagenesis within the four highly conserved apyrase regions of solCD39. Mutation of glutamate 174 to alanine (E174A) and serine 218 to alanine (S218A) resulted in complete and approximately 90% loss of solCD39 enzymatic activity, respectively. Furthermore, compared to wild-type, S57A exhibited a 2-fold increase in ADPase activity without change in ATPase activity, while the tyrosine 127 to alanine (Y127A) mutant lost 50-60% of both ADPase and ATPase activity. The ADPase activity of wild-type solCD39 and each mutant, except for R135A, was greater with calcium as the required divalent cation than with magnesium, but for ATPase activity generally no such preference was observed. Y127A demonstrated the highest calcium/magnesium ADPase activity ratio, 2.8-fold higher than that of wild-type, even though its enzyme activity was greatly reduced. SolCD39 mutants were further characterized by correlating enzymatic with biological activity in an in vitro platelet aggregation system. Each solCD39 mutant was similar to wild-type in reversing platelet aggregation, except for E174A and S218A. E174A, completely devoid of enzymatic activity, failed to inhibit platelet responsiveness, as anticipated. S218A, with 91% loss of ADPase activity, could still reverse platelet aggregation, albeit much less effectively than wild-type solCD39. Thus, glutamate 174 and serine 218 are essential for both the enzymatic and biological activity of solCD39. 相似文献