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21.
Gundelia species are known as “Kenger-kereng dikeni” in Anatolia, and their aerial parts are consumed as food. Also, roots and seeds (disseminules) of the Gundelia species are used to prepare gum and coffee. The chemical contents of ethanol and hexane extracts of disseminules of 17 Gundelia species, 13 of them are endemic, were studied using LC/MS/MS and GC/MS. Additionally, their antioxidant potential and enzyme inhibitory capacity against acetyl- and butyryl-cholinesterase, urease, and tyrosinase were determined. The unsaturated fatty acid ratios of Gundelia species were higher than their saturated fatty acid ratio. The highest sum of oleic and linoleic acid was detected in G. tournefortii var. tenuisecta (70.42 %). β-Sitosterol, α-amyrin, 3-acetyllupeol were identified in 17 Gundelia species by GC/MS, while chlorogenic acid and luteolin by LC/MS/MS as major compounds. The ethanol and hexane extracts of G. siirtica, G. rosea, and G. mesopotamica indicated good cholinesterase inhibitory activity. Among all species, ethanol extract of G. colemerikensis exhibited the best activity in ABTS (IC50: 32.30±0.98 μg/mL), DPPH (IC50: 59.91±0.89 μg/mL), and CUPRAC (A0.5: 57.41±1.03 μg/mL) assays. Ethanol extract of G. colemerikensis also displayed the highest inhibitory activity against butyrylcholinesterase (51.14±0.25 % at 200 μg/mL), urease (51.71±1.75 % at 200 μg/mL), and tyrosinase (39.50±0.85 % at 200 μg/mL) enzymes. According to the chemometric analysis of fatty acids, four groups were observed. Therefore, it is suggested that G. colemerikensis can be used in the pharmaceutical, food, and cosmetic industries due to its antioxidant and enzyme inhibition properties.  相似文献   
22.
The phylogenetic status of arthropods, as inferred from 18S rRNA sequences   总被引:16,自引:4,他引:12  
Partial 18S rRNA sequences of five chelicerate arthropods plus a crustacean, myriapod, insect, chordate, echinoderm, annelid, and platyhelminth were compared. The sequence data were used to infer phylogeny by using a maximum-parsimony method, an evolutionary-distance method, and the evolutionary-parsimony method. The phylogenetic inferences generated by maximum-parsimony and distance methods support both monophyly of the Arthropoda and monophyly of the Chelicerata within the Arthropoda. These results are congruent with phylogenies based on rigorous cladistic analyses of morphological characters. Results support the inclusion of the Arthropoda within a spiralian or protostome coelomate clade that is the sister group of a deuterostome clade, refuting the hypothesis that the arthropods represent the "primitive" sister group of a protostome coelomate clade. Bootstrap analyses and consideration of all trees within 1% of the length of the most parsimonious tree suggest that relationships between the nonchelicerate arthropods and relationships within the chelicerate clade cannot be reliably inferred with the partial 18S rRNA sequence data. With the evolutionary-parsimony method, support for monophyly of the Arthropoda is found in the majority of the combinations analyzed if the coelomates are used as "outgroups." Monophyly of the Chelicerata is supported in most combinations assessed. Our analyses also indicate that the evolutionary-parsimony method, like distance and parsimony, may be biased by taxa with long branches. We suggest that a previous study's inference of the Arthropoda as paraphyletic may be the result of (a) having two few arthropod taxa available for analysis and (b) including long-branched taxa.   相似文献   
23.
OBJECTIVE: This study was to search how change with age of IFN-gamma (IFN-gamma) levels of leprosy patients who had received or still undergoing treatment, their healthy close relatives and healthy people. METHOD: From a total of 39 patients, 28 had received leprosy treatment and recovered with some defects [17 Lepromatous Leprosy(LL), 7 Borderline Lepromatous (BL), 3 Borderlien Tuberculoid (BT), 1 Tuberculoid form (TT)] and 11 (9 LL, 2 BL) were undergoing therapy in a hospital at that moment. Close relatives of the patients included 39 people living with treated patients in the same house and the control group consisted of 39 healthy people. Human IFN-gamma kits were used as a solid phase sandwich ELISA method. RESULTS: The IFN-gamma values of treated leprosy patients, therapy receiving patients, relatives group's and control group's were detected as 11-20 pg/mL, 11-18 pg/mL, 12-145 pg/mL and 12-65 pg/mL respectively. CONCLUSION: According to the statistical evaluation of these three groups, IFN-gamma levels of patients were detected lower than other two groups. According to the age, if IFN-gamma levels were compared, it was detected that significant relationship between relatives groups and interferon gamma levels.  相似文献   
24.

Background

Cigarette smoking causes Chronic Obstructive Pulmonary Disease (COPD), the 3rd leading cause of death in the U.S. CFTR ion transport dysfunction has been implicated in COPD pathogenesis, and is associated with chronic bronchitis. However, susceptibility to smoke induced lung injury is variable and the underlying genetic contributors remain unclear. We hypothesized that presence of CFTR mutation heterozygosity may alter susceptibility to cigarette smoke induced CFTR dysfunction. Consequently, COPD patients with chronic bronchitis may have a higher rate of CFTR mutations compared to the general population.

Methods

Primary human bronchial epithelial cells derived from F508del CFTR heterozygotes and mice with (CFTR+/-) and without (CFTR+/+) CFTR heterozygosity were exposed to whole cigarette smoke (WCS); CFTR-dependent ion transport was assessed by Ussing chamber electrophysiology and nasal potential difference measurements, respectively. Caucasians with COPD and chronic bronchitis, age 40 to 80 with FEV1/FVC < 0.70 and FEV1 < 60% predicted, were selected for genetic analysis from participants in the NIH COPD Clinical Research Network’s Azithromycin for Prevention of Exacerbations of COPD in comparison to 32,900 Caucasian women who underwent prenatal genetic testing. Genetic analysis involved an allele-specific genotyping of 89 CFTR mutations.

Results

Exposure to WCS caused a pronounced reduction in CFTR activity in both CFTR (+/+) cells and F508del CFTR (+/-) cells; however, neither the degree of decrement (44.7% wild-type vs. 53.5% F508del heterozygous, P = NS) nor the residual CFTR activity were altered by CFTR heterozygosity. Similarly, WCS caused a marked reduction in CFTR activity measured by NPD in both wild type and CFTR heterozygous mice, but the severity of decrement (91.1% wild type vs. 47.7% CF heterozygous, P = NS) and the residual activity were not significantly affected by CFTR genetic status. Five of 127 (3.9%) COPD patients with chronic bronchitis were heterozygous for CFTR mutations which was not significantly different from controls (4.5%) (P = NS).

Conclusions

The magnitude of WCS induced reductions in CFTR activity was not affected by the presence of CFTR mutation heterozygosity. CFTR mutations do not increase the risk of COPD with chronic bronchitis. CFTR dysfunction due to smoking is primarily an acquired phenomenon and is not affected by the presence of congenital CFTR mutations.  相似文献   
25.
We investigated the protective effect of vitamin D against liver damage caused by carbon tetrachloride (CCl4). Twenty-four male rats were divided into four equal groups: G1, untreated controls; G2, administered CCl4; G3, administered both CCl4 and vitamin D for 10 weeks; G4, administered CCl4 for 10 weeks and vitamin D for 12 weeks. At the end of experiment, intracardiac blood samples were taken and liver samples were removed. Hepatic damage due to CCl4 was assessed using biochemistry and histopathology. Glutathione (GSH) levels decreased, while malondialdehyde (MDA) levels increased in liver tissues of G2. Alanine transaminase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl-transaminase (GGT) levels increased, while albumin (ALB) levels decreased. Hepatocyte degeneration, lobular disorder, sinusoid dilation, focal necrotic areas, hyperemia, and glycogen loss were observed. Hepatic fibrosis was observed around portal areas and central veins. Bridging fibrous septa were formed between portal veins. By immunohistochemistry, both matrix metalloproteinase-9 (MMP-9) and desmin reactivity were increased. All aspects of liver damage were at least partially prevented in rats treated with vitamin D. Vitamin D appears to act as an antioxidant and anti-fibrotic to protect the rat liver against damage.  相似文献   
26.
Previous studies have demonstrated that murine CD4 Th1 cells lack perforin and use a pathway distinctive from CD8 CTL to express cytotoxicity. Whether the cytotoxic process of Th1 cells can be separated into identifiable stages and how these differences affect this process were determined in this study. We have resolved the cytotoxic process of Th1 clones into three stages identical with those of CD8 CTL, namely, conjugate formation/activation, lethal hit, and effector-independent programming for target DNA fragmentation. By comparing the cytotoxic processes between Th1 clones on Ag-pulsed targets and (PMA+A23187)-activated Th1 clones on unpulsed targets, we have also demonstrated that 1) the requirement of CD4 Th1 cells for de novo synthesis of cytotoxic machinery was partly responsible for the lag time in the induction of target DNA fragmentation by Th1 clones; 2) lethal hit was delivered rapidly; 3) lethal hit under forced contact by centrifugation did not need extracellular Ca2+ and Mg2+; 4) without centrifugation, lethal hit required extracellular Mg2+, but not Ca2+; 5) the average functional half life of the cytotoxic machinery was 54 +/- 24 (n = 4) min. The data demonstrate that the cytotoxic process of Th1 clones uses an activation-dependent cytotoxic machinery to deliver a short-lived, short-ranged, and quick-acting lethal hit to target, which induces a program in target for DNA fragmentation.  相似文献   
27.
The heritable elytral colour/pattern polymorphism of Philaenus spumarius in north-western Black Sea region of Turkey was investigated. A total of 2,530 adult spittlebugs, 1,020 females and 1,510 males were collected and analysed in terms of the 11 most common colour forms. Nine different phenotypes, expressed by six different alleles, were determined: populi (POP), typicus (TYP), trilineatus (TRI), marginellus (MAR), flavicollis (FLA), leucocephalus (LCE), gibbus (GIB), albomaculatus (ALB), and leucophtalmus (LOP). The common phenotypes lateralis (LAT) and quadrimaculatus (QUA) of previous studies were not encountered at all. The predominant phenotype was TYP (63%) in females and males followed by POP (31%). TRI (4%) and melanics (5%) were at close proportions. However, only one site had nine phenotypes altogether. The majority of the sites had only the POP and TYP morphs. The melanic forms were found only in females.  相似文献   
28.
BackgroundThis study planned to investigate the relationship of dynamic thiol/disulfide homeostasis with the prognosis of myelodysplastic syndrome (MDS).Methods80 patients who had been diagnosed with MDS between 2012 and 2017 and who were older than 18 were included in the study together with 80 healthy control subjects. The MDS diagnosis was confirmed using bone marrow aspiration-biopsy immunostaining. Dynamic thiol/disulfide homeostasis and ischemia-modified albumin (IMA) levels were examined.ResultsThe average IMA (0.71±0.08 vs. 0.67±0.09; p=0.002), median disulfide (18.0 vs. 11.6; p<0.001), median disulfide/native thiol (6 vs. 3; p<0.001), and median disulfide/total thiol (5.4 vs. 2.9; p<0.001) were found higher in the MDS patients compared to control group, and the median hemoglobin, median white blood cell count, median neutrophil count, median lymphocyte count, average native thiol (290.7±48.5 vs. 371.5±103.8; p<0.001), average total thiol (328.2±48.9 vs. 393±105.5; p<0.001), and average native thiol/total thiol (%) (88.3±4.3 vs. 94.2±2.1; p<0.001) were found to below. Risk factors such as collagen tissue disease (HR:9.17; p=0.005), MDS-EB-1 (HR:10.14; p=0.032), MDS-EB-2 (HR:18.2; p=0.043), and disulfide/native thiol (HR:1.17; p=0.023) were found as the independent predictors anticipating progression to acute myeloid leukemia. In the Cox regression model, risk factors such as age (HR:1.05; p=0.002), MDS-EB-1 (HR:12.58; p<0.001), MDS-EB-2 (HR:5.75; p=0.033), disulfide/native thiol (HR:1.14; p=0.040), and hemoglobin (HR:0.64; p=0.007) were found as predictors anticipating for mortality.ConclusionsWe can argue that dynamic thiol/disulfide homeostasis could have significant effects on both the etiopathogenesis and the survival of patients with MDS, and it could be included in new prognostic scoring systems.  相似文献   
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