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21.
Plant Cell, Tissue and Organ Culture (PCTOC) - Ziziphora persica (Lamiaceae) has been used as infusions and decoctions in traditional medicine for various purposes such as sedative, carminative,...  相似文献   
22.
Cardiovascular diseases are the main cause of death globally. Many attempts have been done to ameliorate the pathological changes after the occurrence of myocardial infarction. Curcumin is touted as a polyphenol phytocompound with appropriate cardioprotective properties. In this study, the therapeutic effect of curcumin was investigated on acute myocardial infarction in the model of rats. Rats were classified into four groups; control, isoproterenol hydrochloride (ISO) (100 mg/kbw), curcumin (50 mg/kbw), and curcumin plus ISO treatment groups. After 9-day administration of curcumin, levels of lactate dehydrogenase (LDH), creatine kinase (CK), and cardiac troponin I (cTnI) were determined. Superoxide dismutase (SOD) and malondialdehyde (MDA) contents were measured to investigate the oxidative status in infarct rats received curcumin. By using H & E staining, tissue inflammation was performed. Masson’s trichrome staining was conducted to show cardiac remodeling and collagen deposition. The number of apoptotic cells was determined by using the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Data showed the serum decrease of LDH, CK, and cTnI in infarct rats after curcumin intake compared to the rats given (ISO) ( P < 0.05). Curcumin was found to reduce oxidative status by reducing SOD and MDA contents ( P < 0.05). Gross and microscopic examinations revealed that the decrease of infarct area, inflammation response and collagen deposition in rats given ISO plus curcumin ( P < 0.05). We noted the superior effect of curcumin to reduce the number of apoptotic cardiomyocytes after 9 days. Data point the cardioprotective effect of curcumin to diminish the complication of infarction by the reduction of cell necrosis and apoptosis in a rat model of experimental infarction.  相似文献   
23.
Dihematoporphyrin ether, also known as Photofrin-II (Pf-II) is currently used in the diagnosis and management of a variety of epithelial neoplasms, in a modality known as photodynamic therapy (PDT). A major drawback of these porphyrins for PDT is their ability to evoke prolonged cutaneous photosensitization. The mechanism of tumor ablation and cutaneous photosensitization by these photosensitizers is thought to relate to the generation of one or more reactive oxygen species such as superoxide anion, singlet oxygen and hydroxyl radical. However, the role of these oxygen species has not been established unequivocally. In this study, the mechanism of Pf-II-mediated cutaneous photosensitization was examined using murine ear swelling as a marker. The mice treated with Pf-II and light demonstrated two-fold enhancement of ear swelling whereas animals treated with the SOD mimic, beta-carotene and dimethyl sulfoxide (DMSO) had considerably less ear swelling (p less than 0.01). The observed protective effect was dependent on the dose of each quencher and followed the pattern SOD mimic DMSO beta-carotene. The histopathologic alterations caused by Pf-II photosensitization were significantly alleviated by pretreatment with SOD mimic whereas beta-carotene and (DMSO) were less effective. Inhibitors of superoxide dismutase (sodium diethyldithiocarbamate) and catalase (hydroxyl amine and 3, amino 1,2,4-triazole) augmented Pf-II-mediated cutaneous photosensitization. These data provide the first in vivo evidence for the involvement of superoxide anion in cutaneous porphyrin photosensitization.  相似文献   
24.
A suite of small unilamellar vesicles (SUVs) composed of mixtures of phospholipids and cholesterol (CH) or the synthetic surfactant dihexadecyl phosphate (DHP) and cholesterol was investigated using a homologous series of solvatochromic pi* indicators coupled with size exclusion methods and photon correlation spectroscopy (PCS). The solvatochromic method, which is based on the measurement of solvent-dependent shifts in lambda(max) from UV-Vis spectra of solubilized indicators, was used to quantify the dipolarity and polarizability (pi*) of probe solvation environments. The partitioning of the series of individual di-n-alkyl-p-nitroaniline (DNAP) pi* indicators in PG(24)PC(46)Chol(30) and DHP(70)Chol(30) SUVs was examined as a function of the head group structure as well as the method of dye-vesicle preparation. Solubilization of the larger more hydrophobic probes in the bilayer portion of PG(24)PC(46)Chol(30) SUVs was aided through physical entrapment. Such physical methods were not needed for the smaller indicators or for the range of indicators in the DHP(70)Chol(30) dispersions. Extrusion and size-exclusion chromatographic methodologies for the preparation of physically entrapped dopants in SUVs of fixed size range demonstrated that the larger (longer alkyl chain) dopants in the series resided in PG(24)PC(46)Chol(30) liposomes with a wider range of sizes, while the smaller more polar solutes tended to be entrapped in smaller vesicles with a narrower size range.  相似文献   
25.
Boxfishes (Teleostei: Ostraciidae) are rigid-body, multi-propulsorswimmers that exhibit unusually small amplitude recoil movementsduring rectilinear locomotion. Mechanisms producing the smoothswimming trajectories of these fishes are unknown, however.Therefore, we have studied the roles the bony carapaces of thesefishes play in generating this dynamic stability. Features ofthe carapaces of four morphologically distinct species of boxfisheswere measured, and anatomically-exact stereolithographic modelsof the boxfishes were constructed. Flow patterns around eachmodel were investigated using three methods: 1) digital particleimage velocimetry (DPIV), 2) pressure distribution measurements,and 3) force balance measurements. Significant differences inboth cross-sectional and longitudinal carapace morphology weredetected among the four species. However, results from the threeinterrelated approaches indicate that flow patterns around thevarious carapaces are remarkably similar. DPIV results revealedthat the keels of all boxfishes generate strong longitudinalvortices that vary in strength and position with angle of attack.In areas where attached, concentrated vorticity was detectedusing DPIV, low pressure also was detected at the carapace surfaceusing pressure sensors. Predictions of the effects of both observedvortical flow patterns and pressure distributions on the carapacewere consistent with actual forces and moments measured usingthe force balance. Most notably, the three complementary experimentalapproaches consistently indicate that the ventral keels of allboxfishes, and in some species the dorsal keels as well, effectivelygenerate self-correcting forces for pitching motions—acharacteristic that is advantageous for the highly variablevelocity fields in which these fishes reside.  相似文献   
26.
We use the Reciprocal Smallest Distance (RSD) algorithm to identify amino acid sequence orthologs in the Chinese and Indian rhesus macaque draft sequences and estimate the evolutionary distance between such orthologs. We then use GOanna to map gene function annotations and human gene identifiers to the rhesus macaque amino acid sequences. We conclude methodologically by cross-tabulating a list of amino acid orthologs with large divergence scores with a list of genes known to be involved in SIV or HIV pathogenesis. We find that many of the amino acid sequences with large evolutionary divergence scores, as calculated by the RSD algorithm, have been shown to be related to HIV pathogenesis in previous laboratory studies. Four of the strongest candidate genes for SIVmac resistance in Chinese rhesus macaques identified in this study are CDK9, CXCL12, TRIM21, and TRIM32. Additionally, ANKRD30A, CTSZ, GORASP2, GTF2H1, IL13RA1, MUC16, NMDAR1, Notch1, NT5M, PDCD5, RAD50, and TM9SF2 were identified as possible candidates, among others. We failed to find many laboratory experiments contrasting the effects of Indian and Chinese orthologs at these sites on SIVmac pathogenesis, but future comparative studies might hold fertile ground for research into the biological mechanisms underlying innate resistance to SIVmac in Chinese rhesus macaques.  相似文献   
27.
Heavy metals accumulation in soils poses a potential threat to ecosystems, which, in turn, threat human health through food chains. Therefore, remediating polluted sites is important to environment and humanity. In this investigation, statice (L. sinuatum) was exposed to Cd (0, 15, 30, 60 mg kg?1 soil) or Pb (0, 100, 150, 300 mg kg?1 soil) in a pot experiment to assess its tolerance to each metal and study its phytoaccumulation capability. The benefits of mycorrhization (mixture of Glomus mosseae and G. intraradices) were also studied simultaneously. Single exposure to Cd or Pb reduced the plant growth, but statice was still relatively tolerant to both metals. The plants accumulated both metals in their roots; little was translocated to the shoots. Total Pb and total Cd accumulated by the roots was approximately 2 and 3 times higher in mycorrhizal than non-mycorrhizal plants (49 versus 147 and 595 versus 956 μg plant?1) respectively; however, mycorrhization alleviated metal phytotoxicity. The results suggest that statice is a potential candidate to be used as an ornamental plant in lead and cadmium polluted sites, mainly inoculated with arbuscular mycorrhizae. Besides that, it would be useful as a Pb or Cd controlling agent by means of phytostabilization.  相似文献   
28.
In this study, the use of trimethylchitosan (TMC), by higher solubility in comparison with chitosan, in alginate/chitosan nanoparticles containing cationic β-cyclodextrin polymers (CPβCDs) has been studied, with the aim of increasing insulin uptake by nanoparticles. Firstly, TMCs were synthesized by iodomethane, and CPβCDs were synthesized within a one-step polycondensation reaction using choline chloride (CC) and epichlorohydrine (EP). Insulin–CβCDPs complex was prepared by mixing 1:1 portion of insulin and CPβCDs solutions. Then, nanoparticles prepared in a three-step procedure based on the iono-tropic pregelation method. Nanoparticles screened using experimental design and Placket Burman methodology to obtain minimum size and polydispercity index (pdI) and the highest entrapment efficiency (EE). CPβCDs and TMC solution concentration and pH and alginate and calcium chloride solution concentrations are found as the significant parameters on size, PdI, and EE. The nanoparticles with proper physicochemical properties were obtained; the size, PdI, and EE% of optimized nanoparticles were reported as 150.82 ± 21 nm, 0.362 ± 0.036, and 93.2% ± 4.1, respectively. The cumulative insulin release in intestinal condition achieved was 50.2% during 6 h. By SEM imaging, separate, spherical, and nonaggregated nanoparticles were found. In the cytotoxicity studies on Caco-2 cell culture, no significant cytotoxicity was observed in 5 h of incubation, but after 24 h of incubation, viability was decreased to 50% in 0.5 mμ of TMC concentration. Permeability studies across Caco-2 cells had been carried out, and permeability achieved in 240 min was 8.41 ± 0.39%, which shows noticeable increase in comparison with chitosan nanoparticles. Thus, according to the results, the optimized nanoparticles can be used as a new insulin oral delivery system.KEY WORDS: alginate, cationic β-cyclodextrin, insulin nanoparticle, oral delivery, trimethyl chitosan  相似文献   
29.
30.
In relation to the growing recent interest in the establishment of sperm‐mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0–500 ng) of pcDNA/his/Lac‐Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live‐immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA‐incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X‐Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live‐immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live‐immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. Mol. Reprod. Dev. 77:868–875, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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