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21.
For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI.  相似文献   
22.
Herpes simplex virus 1 (HSV-1) is a double-stranded DNA virus that replicates in the nucleus of its human host cell and is known to interact with many cellular DNA repair proteins. In this study, we examined the role of cellular mismatch repair (MMR) proteins in the virus life cycle. Both MSH2 and MLH1 are required for efficient replication of HSV-1 in normal human cells and are localized to viral replication compartments. In addition, a previously reported interaction between MSH6 and ICP8 was confirmed by coimmunoprecipitation and extended to show that UL12 is also present in this complex. We also report for the first time that MLH1 associates with ND10 nuclear bodies and that like other ND10 proteins, MLH1 is recruited to the incoming genome. Knockdown of MLH1 inhibits immediate-early viral gene expression. MSH2, on the other hand, which is generally thought to play a role in mismatch repair at a step prior to that of MLH1, is not recruited to incoming genomes and appears to act at a later step in the viral life cycle. Silencing of MSH2 appears to inhibit early gene expression. Thus, both MLH1 and MSH2 are required but appear to participate in distinct events in the virus life cycle. The observation that MLH1 plays an earlier role in HSV-1 infection than does MSH2 is surprising and may indicate a novel function for MLH1 distinct from its known MSH2-dependent role in mismatch repair.  相似文献   
23.
Wastewater discharges may increase the populations of pathogens, including Escherichia coli, and of antimicrobial-resistant strains in receiving waters. This study investigated the impact of UV and peracetic acid (PAA) disinfection on the prevalence of virulence and antimicrobial resistance genes in uropathogenic Escherichia coli (UPEC), the most abundant E. coli pathotype in municipal wastewaters. Laboratory disinfection experiments were conducted on wastewater treated by physicochemical, activated sludge, or biofiltration processes; 1,766 E. coli isolates were obtained for the evaluation. The target disinfection level was 200 CFU/100 ml, resulting in UV and PAA doses of 7 to 30 mJ/cm2 and 0.9 to 2.0 mg/liter, respectively. The proportions of UPECs were reduced in all samples after disinfection, with an average reduction by UV of 55% (range, 22% to 80%) and by PAA of 52% (range, 11% to 100%). Analysis of urovirulence genes revealed that the decline in the UPEC populations was not associated with any particular virulence factor. A positive association was found between the occurrence of urovirulence and antimicrobial resistance genes (ARGs). However, the changes in the prevalence of ARGs in potential UPECs were different following disinfection, i.e., UV appears to have had no effect, while PAA significantly reduced the ARG levels. Thus, this study showed that both UV and PAA disinfections reduced the proportion of UPECs and that PAA disinfection also reduced the proportion of antimicrobial resistance gene-carrying UPEC pathotypes in municipal wastewaters.  相似文献   
24.
Aliskiren hemifumarate (ALS) and amlodipine besylate (AML) were simultaneously determined by two different spectrofluorimetric techniques. The first technique depends on direct measurement of the steady‐state fluorescence intensities of ALS and AML at 313 nm and 452 nm upon excitation at 290 and 375 nm, respectively, in a solvent composed of methanol and water (10: 90, v/v) . The second technique utilizes synchronous fluorimetric quantitative screening of the emission spectra of ALS and AML at 272 and 366 nm, respectively using Δλ of 97 nm. Effects of different solvents and surfactants on relative fluorescence intensity were studied. The method was validated according to ICH guidelines. Linearity, accuracy and precision were found to be satisfactory in both techniques over the concentration ranges of 1–15 and 0.4–4 µg/mL for ALS and AML, respectively. In the first technique, limit of detection and limit of quantification were estimated and found to be 0.256 and 0.776 µg/mL for ALS as well as 0.067 and 0.204 µg/mL for AML, respectively. Also, limit of detection and limit of quantification were calculated in the synchronous method and found to be 0.293 and 0.887 µg/mL for ALS as well as 0.034 and 0.103 µg/mL for AML, respectively. The methods were successfully applied for the determination of the two drugs in their co‐formulated tablets. The results were compared statistically with reference methods and no significant difference was found. The developed methods are rapid, sensitive, inexpensive and accurate for the quality control and routine analysis of the cited drugs in bulk and in pharmaceutical preparations without pre‐separation. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
25.
Applied Microbiology and Biotechnology - Taxol is an anticancer identified in both endophytic fungus and its host plant. Plant Taxol is a diterpenoid with geranylgeranyl diphosphate (GGPP) mediates...  相似文献   
26.
The absorption, emission and excitation spectra of indium(III) tetraphenylporphyrinchloride (In(III)TPPCl) and indium(III)octaethylporphyrinchloride (In(III)OEPCl) methanolic solutions have been studied and compared with their metal-free bases. The study reveals a strong interaction between indium ion and the porphyrin π-systems.The photolability of the above-mentioned compounds has been studied in deoxygenated methalonic solutions using sunlight and/or UV-light in excitation. A fragmentation mechanism is proposed to account for the consumption of the porphyrin systems.  相似文献   
27.
A series of novel 1,2,3-triazole-linked ciprofloxacin-chalcones 4a-j were synthesised as potential anticancer agents. Hybrids 4a-j exhibited remarkable anti-proliferative activity against colon cancer cells. Compounds 4a-j displayed IC50s ranged from 2.53-8.67 µM, 8.67–62.47 µM, and 4.19–24.37 µM for HCT116, HT29, and Caco-2 cells; respectively, whereas the doxorubicin, showed IC50 values of 1.22, 0.88, and 4.15 µM. Compounds 4a, 4b, 4e, 4i, and 4j were the most potent against HCT116 with IC50 values of 3.57, 4.81, 4.32, 4.87, and 2.53 µM, respectively, compared to doxorubicin (IC50 = 1.22 µM). Also, hybrids 4a, 4b, 4e, 4i, and 4j exhibited remarkable inhibitory activities against topoisomerase I, II, and tubulin polymerisation. They increased the protein expression level of γH2AX, indicating DNA damage, and arrested HCT116 in G2/M phase, possibly through the ATR/CHK1/Cdc25C pathway. Thus, the novel ciprofloxacin hybrids could be exploited as potential leads for further investigation as novel anticancer medicines to fight colorectal carcinoma.  相似文献   
28.
Saccharomyces boulardii was used for antimicrobial peptides production. Separation process of produced antimicrobial peptides was conducted using ultrafiltration technique through dialysis membranes with porous 10 (MWCO) kDa. The inhibition activity was determined against four bacterial isolates. As a result, higher inhibition zone against Bacillus cereus were 26, 29 and 33 mm after adding 50, 75 and 100 µL of concentrated peptide, respectively. After that, peptide passed through the Sephadex G-50 column to achieve purified peptide using gel filtration. The high activity of purified peptide was confirmed based on the second peak reaching to 37 mm of bacterial inhibition zone while other peaks did not show any inhibition against tested bacteria. Some of the important characteristics of purified bioactive peptide were applied. Antimicrobial peptides stability was studied and found to be stable at pH range from 5 to 7 values studied in addition to its inhibition activity reached to 100%. Regarding thermal stability, it was observed that the peptide was fully activity at a both 60–80 °C for 30 min. Moreover, molecular weight of a peptide was identified using electrophoresis technique with SDS measured at 5792 Dalton.  相似文献   
29.
The interaction of glutamine availability and glucose homeostasis during and after exercise was investigated, measuring whole body glucose kinetics with [3-3H]glucose and net organ balances of glucose and amino acids (AA) during basal, exercise, and postexercise hyperinsulinemic-euglycemic clamp periods in six multicatheterized dogs. Dogs were studied twice in random treatment order: once with glutamine (12 micromol.kg(-1).min(-1); Gln) and once with saline (Con) infused intravenously during and after exercise. Plasma glucose fell by 7 mg/dl with exercise in Con (P < 0.05), but it did not fall with Gln. Gln further stimulated whole body glucose production and utilization an additional 24% above a normal exercise response (P < 0.05). Net hepatic uptake of glutamine and alanine was greater with Gln than Con during exercise (P < 0.05). Net hepatic glucose output was increased sevenfold during exercise with Gln (P < 0.05) but not with Con. Net hindlimb glucose uptake was increased similarly during exercise in both groups (P < 0.05). During the postexercise hyperinsulinemic-euglycemic period, glucose production decreased to near zero with Con, but it did not decrease below basal levels with Gln. Gln increased glucose utilization by 16% compared with Con after exercise (P < 0.05). Furthermore, net hindlimb glucose uptake in the postexercise period was increased approximately twofold vs. basal with Gln (P < 0.05) but not with Con. Net hepatic uptake of glutamine during the postexercise period was threefold greater for Gln than Con (P < 0.05). In conclusion, glutamine availability modulates glucose homeostasis during and after exercise, which may have implications for postexercise recovery.  相似文献   
30.
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