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21.
A mouse genomic clone containing a lactate dehydrogenase-A (LDH-A)
processed pseudogene and a B1 repetitive element was isolated, and a
nucleotide sequence of approximately 3 kb was determined. The pseudogene
and B1 element are flanked by perfect 13-bp repeats, and the B1 sequence
starts at 14 nucleotides 3' to the presumptive polyadenylation signal of
the pseudogene. The nucleotide sequences of the LDH-A genes and processed
pseudogenes from mouse, rat, and human were compared, and a phylogenetic
tree was constructed. The rate and pattern of nucleotide substitutions in
the LDH-A pseudogenes are similar to previously reported results (Li et al.
1984). The average rate of nucleotide substitutions in the LDH-A
pseudogenes is 4.3 X 10(- 9)/site/year. The substitutions of C----T and
G----A are most frequent, and A----G substitutions are relatively high. The
rate of synonymous substitutions in the LDH-A genes is 5.3 X 10(-9), which
is not significantly higher than the average rate of 4.7 X 10(-9) for 35
mammalian genes. The rate of nonsynonymous substitutions in the LDH-A genes
is 0.20 X 10(-9), which is considerably lower than the average rate of 0.88
X 10(-9) for 35 mammalian genes. Thus, the mammalian LDH-A gene appears to
be highly conserved in evolution.
相似文献
22.
The scientific and medical community remains skeptical regarding the efficacy of nutrition for osteoarthritis despite their
broad acceptation by patients. In this context, this paper systematically reviews human clinical trials evaluating the effects
of nutritional compounds on osteoarthritis. We searched the Medline, Embase, and Biosis databases from their inception to
September 2005 using the terms random, double-blind method, trial, study, placebo, and osteoarthritis. We selected all peer-reviewed
articles reporting the results of randomised human clinical trials (RCTs) in osteoarthritis that investigated the effects
of oral interventions based on natural molecules. Studies on glucosamine and chondroitin sulfate were excluded. The quality
of the RCTs was assessed with an osteoarthritic-specific standardised set of 12 criteria and a validated instrument. A best-evidence
synthesis was used to categorise the scientific evidence behind each nutritional compound as good, moderate, or limited. A
summary of the most relevant in vitro and animal studies is used to shed light on the potential mechanisms of action. Inclusion criteria were met by 53 RCTs out
of the 2,026 identified studies. Good evidence was found for avocado soybean unsaponifiables. Moderate evidence was found
for methylsulfonylmethane and SKI306X, a cocktail of plant extracts. Limited evidence was found for the Chinese plant extract
Duhuo Jisheng Wan, cetyl myristoleate, lipids from green-lipped mussels, and plant extracts from Harpagophytum procumbens. Overall, scientific evidence exists for some specific nutritional interventions to provide symptom relief to osteoarthritic
patients. It remains to be investigated whether nutritional compounds can have structure-modifying effects. 相似文献
23.
Sheung-Tak Cheng Rosanna WL Lau Emily PM Mak Natalie SS Ng Linda CW Lam Helene H Fung Julian CL Lai Timothy Kwok Diana TF Lee 《Trials》2012,13(1):1-10
Background
Patients with ST-elevation myocardial infarction (STEMI) not treated with primary or rescue percutaneous coronary intervention (PCI) are at risk for recurrent ischemia, especially when viability in the infarct-area is present. Therefore, an invasive strategy with PCI of the infarct-related coronary artery in patients with viability would reduce the occurrence of a composite end point of death, reinfarction, or unstable angina (UA).Methods
Patients admitted with an (sub)acute myocardial infarction, who were not treated by primary or rescue PCI, and who were stable during the first 48 hours after the acute event, were screened for the study. Eventually, we randomly assigned 216 patients with viability (demonstrated with low-dose dobutamine echocardiography) to an invasive or a conservative strategy. In the invasive strategy stenting of the infarct-related coronary artery was intended with abciximab as adjunct treatment. Seventy-five (75) patients without viability served as registry group. The primary endpoint was the composite of death from any cause, recurrent myocardial infarction (MI) and unstable angina at one year. As secondary endpoint the need for (repeat) revascularization procedures and anginal status were recorded.Results
The primary combined endpoint of death, recurrent MI and unstable angina was 7.5% (8/106) in the invasive group and 17.3% (19/110) in the conservative group (Hazard ratio 0.42; 95% confidence interval [CI] 0.18-0.96; p = 0.032). During follow up revascularization-procedures were performed in 6.6% (7/106) in the invasive group and 31.8% (35/110) in the conservative group (Hazard ratio 0.18; 95% CI 0.13-0.43; p < 0.0001). A low rate of recurrent ischemia was found in the non-viable group (5.4%) in comparison to the viable-conservative group (14.5%). (Hazard-ratio 0.35; 95% CI 0.17-1.00; p = 0.051).Conclusion
We demonstrated that after acute MI (treated with thrombolysis or without reperfusion therapy) patients with viability in the infarct-area benefit from a strategy of early in-hospital stenting of the infarct-related coronary artery. This treatment results in a long-term uneventful clinical course. The study confirmed the low risk of recurrent ischemia in patients without viability.Trial registration
ClinicalTrials.gov: NCT00149591. 相似文献24.
In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean. 相似文献
25.
Isolation and characterization of the cell-associated region of group A streptococcal M6 protein. 总被引:34,自引:8,他引:34 下载免费PDF全文
DNA sequence analysis of the complete M6 protein gene revealed 19 hydrophobic amino acids at the C terminus which could act as a membrane anchor and an adjacent proline- and glycine-rich region likely to be located in the cell wall. To define this region within the cell wall and its role in attaching the molecule to the cell, we isolated the cell-associated fragment of the M protein. Assuming that the cell-associated region of the M protein would be embedded within the wall and thus protected from trypsin digestion, cells were digested with this enzyme, and the wall-associated M protein fragment was released by phage lysin digestion of the peptidoglycan. With antibody probes prepared to synthetic peptides of C-terminal sequences, a cell wall-associated M protein fragment (molecular weight, 16,000) was identified and purified. Amino acid sequence analysis placed the N terminus of the 16,000-molecular-weight fragment at residue 298 within the M sequence. Amino acid composition of this peptide was consistent with a C-terminal sequence lacking the membrane anchor. Antibody studies of nitrous acid-extracted whole bacteria suggested that, in addition to the peptidoglycan-associated region, a 65-residue helical segment of the C-terminal domain of the M protein is embedded within the carbohydrate moiety of the cell wall. Since no detectable amino sugars were associated with the wall-associated fragment, the C-terminal region of the M6 molecule is likely to be intercalated within the cross-linked peptidoglycan and not covalently linked to it. Because the C-terminal region of the M molecule is highly homologous to the C-terminal end of protein A from staphylococci and protein G from streptococci, it is likely that the mechanism of attachment of these proteins to the cell wall is conserved. 相似文献
26.
Vascular smooth muscle cells (VSMC) may be programmed by nutrient deprivation. We found that after 2 and 12 h exposure to 75% reduced amino acids, the release of basic fibroblast growth factor (bFGF) and transforming growth factor beta1 (TGF beta 1) from VSMC was significantly greater than that from cells maintained in control medium [2572.0 (546.3) vs 602.1 (241.7), P=0.001 and 16 028.0 (2192. 4) vs 13 027.3 (1233.5) pg/10(6)cells, P=0.022 respectively]. These differences were magnified after two passages of exposure for both bFGF (P=0.0001) and TGF beta 1 (P=0.0001). The stimulated release of VEGF by hypoxia and bFGF was unaffected. Amino acid deprivation of human VSMC is associated with a patterned release of angiogenic cytokines which could be relevant to the programmed changes in VSMC phenotype. 相似文献
27.
SS Padala MA Kiresur A Ananthaneni VS Guduru HK Puneeth B Bhavana 《Biotechnic & histochemistry》2013,88(5):336-339
Toto bodies are eosinophilic structures that resemble the cells of the superficial cell layer of the oral epithelium. Toto bodies commonly are associated with inflammatory gingival and other mucosal lesions including pyogenic granuloma, irritational fibroma, epulis fissuratum, peripheral giant cell granuloma and inflammatory hyperplastic gingivitis. We evaluated staining characteristics of Toto bodies to establish their origin and to identify their significance in lesions. We investigated pyogenic granuloma, fibroma and leukoplakia with epithelium that exhibited Toto bodies after hematoxylin and eosin (staining. Sections were stained with Alcian blue, periodic acid-Schiff and Ayoub-Shklar stains to evaluate staining intensity and distribution. More Toto bodies were found in pyogenic granuloma than in fibroma and leukoplakia. PAS and Alcian blue staining exhibited mild intensity and did not establish the origin of Toto bodies. High staining intensity and diffuse distribution of stain was observed using Ayoub-Shklar staining, which indicated that Toto bodies originate from keratin. 相似文献
28.
Ritesh N. Sharma Franklin P. Xavier Kamala K. Vasu Subhash C. Chaturvedi Shyam S. Pancholi 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):890-897
A series of novel 4-Benzyl-1,3-thiazole derivatives was synthesized by applying analogue-based drug design approach and they were screened for anti-inflammatory activity. Darbufelone (CI 1004) a dual COX/LOX inhibitor, served as a lead molecule for designing a molecular scaffold. The derivatives with the 1,3 thiazole molecular scaffold bearing a side chain at position-2 resembling that of Romazarit (Ro-31-3948) were synthesized. The substitution at the second position of thiazole scaffold consisted of either carbalkoxy amino or aryl amino side chain. The introduction of an NH linker at the second position was the bioisoteric approach to impart the metabolic stability to the carbalkoxy side chains in designed molecules so as to avoid the likelihood of generating toxic moieties, like in Romazarit, which was withdrawn due to its toxicity profile. An important outcome of this study is the optimization of the substitution at the second position of the thiazole scaffold in eliciting better biological activity. The biological activity exhibited by the two designed series were in the order of carbalkoxy amino series > phenyl amino series. Molecule RS31 had emerged to be best compound in the whole series, having the side chain -NH-(C = O)O-R which resemble to Romazerit with 1,3 thiazole scaffold and substituted phenyl carbonyl group at fifth position derived from the retro-analysis of Darbufelone. This novel three-point pharmacophore, which is necessarily evolved from a lead-based drug design strategy, has opened up new avenues in designing of molecules acting on more than one rate-limiting step along the inflammatory cascade. 相似文献
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