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81.
Roots and barks of various Berberis species are used as folk remedy for the treatment of various inflammatory diseases such as lumbago, rheumatism and to reduce fever. Six isoquinoline alkaloids namely berberine, berbamine, palmatine, oxyacanthine, magnoflorine, and columbamine were isolated as the main components of alkaloidal fraction from the roots of Turkish Berberis species and effects were studied using various in vivo models in mice. All alkaloids inhibited inflammations in varying degrees, among them berberine, berbamine and palmatine were shown to possess significant and dose-dependent inhibitory activity against serotonin-induced hind paw oedema both on oral and topical applications and acetic acid-induced increase in vascular permeability on oral administration. Moreover, these three alkaloids were also shown to possess dose-dependent antinociceptive activity, which assessed by using the model based on the inhibition of p-benzoquinone-induced writhing movements as well as antipyretic activity on FCA-induced increased rectal temperature on subacute administration. However, all alkaloids induced gastric lesions in varying degrees.  相似文献   
82.
A common and histologically well defined subtype of glioma are the oligodendroglial brain tumors. Approximately 70% of all oligodendrogliomas have a combined loss of the entire 1p and 19q chromosomal arms. This remarkably high frequency suggests that the remaining arms harbor yet to be identified tumor suppressor genes. Identification of these causal genetic changes in oligodendrogliomas is important because they form direct targets for treatment. In this study we therefore performed targeted resequencing of all exons, microRNAs, splice sites and promoter regions residing on 1p and 19q on 7 oligodendrogliomas and 4 matched controls. Only one missense mutation was identified in a single sample in the ARHGEF16 gene. This mutation lies within- and disrupts the conserved PDZ binding domain. No similar ARHGEF16 mutations or deletions were found in a larger set of oligodendrogliomas. The absence of common somatic changes within genes located on 1p and 19q in three out of four samples indicates that no additional "second hit" is required to drive oncogenic transformation on either chromosomal arm.  相似文献   
83.
The silver fir woolly adelgid, Dreyfusia nordmannianae, is the most severe pest occurring on Abies nordmanniana in Central and Northern Europe. The adelgid is particularly damaging to trees in Christmas tree plantations. Dreyfusia nordmannianae is native to the Caucasus region and alien to Europe, where its natural enemy complex is less diverse compared to its area of origin. Mitochondrial and nuclear DNA sequence data from the samples of D. nordmannianae collected in its native range and Europe and from the samples of Dreyfusia piceae and Dreyfusia prelli collected in Europe and North America were examined for phylogenetic structure. There was no evidence of differentiation, suggesting that these Dreyfusia species have recently diverged or require taxonomic revision. All existing published and unpublished reports on natural enemies of D. nordmannianae in its place of origin were reviewed, with the purpose of selecting agents for classical biological control in Europe. The literature review suggested that the most promising agent was the Chamaemyiidae fly, Leucopis hennigrata. A new survey in D. nordmannianae's area of origin – Turkey, Georgia and Russia – showed that L. hennigrata was present in all localities. It was particularly abundant in Turkey, where its impact on populations of D. nordmannianae appears to be high. Its use as a biological control agent is discussed, as well as other biological control strategies.  相似文献   
84.
Pollen plays an important role in the development and exacerbation of allergic diseases. We aimed to investigate the days with highest counts of the most allergenic pollens and to identify the meteorological factors affecting pollen counts in the atmosphere of Ankara, Turkey. Airborne pollen measurements were carried out from 2005 to 2008 with a Burkard volumetric 7-day spore trap. Microscope counts were converted into atmospheric concentrations and expressed as pollen grains/m3. Meteorological parameters were obtained from the State Meteorological Service. All statistical analyses were done with pollen counts obtained from March to October for each year. The percentages of tree, grass and weed pollens were 72.1% (n = 24,923), 12.8% (n = 4,433) and 15.1% (n = 5,219), respectively. The Pinaceae family from tree taxa (39% to 57%) and the Chenopodiaceae/Amaranthaceae family from weed taxa, contributed the highest percentage of pollen (25% to 43%), while from the grass taxa, only the Poaceae family was detected from 2005 to 2008. Poaceae and Chenopodiaceae/Amaranthaceae families, which are the most allergenic pollens, were found in high numbers from May to August in Ankara. In multiple logistic regression analysis, wind speed (OR = 1.18, CI95% = 1.02–1.36, P = 0.023) for tree pollen, daily mean temperature (OR = 1.10, CI95% = 1.04–1.17, P = 0.001) and sunshine hours (OR = 1.15, CI95% = 1.01–1.30, P = 0.033) for grass pollen, and sunshine hours (OR = 3.79, CI95% = 1.03–13.92, P = 0.044) for weed pollen were found as significant risk factors for high pollen count. The pollen calendar and its association with meteorological factors depend mainly on daily temperature, sunshine hours and wind speed, which may help draw the attention of physicians and allergic patients to days with high pollen counts.  相似文献   
85.
Carbonic anhydrase (CA; EC 4.2.1.1) was purified from the gill of the teleost fish Dicentrarchus labrax (European seabass). The purification procedure consisted of a single step affinity chromatography on Sepharose 4B-tyrosine-sulfanilamide. The enzyme was purified 84.9-fold with a yield of 58%, and a specific activity of 838.9 U/mg proteins. It has an optimum pH at 8.0; an optimum temperature at 10°C. The kinetic parameters of this enzyme were determined for its esterase activity, with 4-nitrophenyl acetate (NPA) as substrate. The following anions, H?NSO??, I?, SCN?, NO??, NO??, N??, Br?, Cl?, SO?2?, and F? showed inhibitory effects on the enzyme. Sulfamic acid, iodide, and thiocyanate exhibited the strongest inhibitory action, in the micromolar range (K(i)s of 87-187 μM). NO??, NO?? and N?? were moderate inhibitors, whereas other anions showed only weak actions. All tested anions inhibited the enzyme in a competitive manner. Our findings indicate that these anions inhibit the fish enzyme in a similar manner to other α-CAs from mammals investigated earlier, but the susceptibility to various anions differs significantly between the fish and mammalian CAs.  相似文献   
86.
The antimicrobial activity of the acetone, chloroform, diethyl ether, methanol, and petroleum ether extracts of the lichen Parmelia sulcata and its salazinic acid constituent have been screened against twenty eight food-borne bacteria and fungi. All of the extracts with the exception of the petroleum ether extract showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Yersinia enterocolitica, Staphylococcus aureus, Streptococcus faecalis, Candida albicans, Candida glabrata, Aspergillus niger, Aspergillus fumigatus, and Penicillium notatum. Salazinic acid did not show antimicrobial activity against L. monocytogenes, P. vulgaris, Y. enterocolitica, and S. faecalis but showed activity against Pseudomonas aeruginosa and Salmonella typhimurium as well. The MIC values of the extracts and the acid for the bacteria and fungi have also been determined.  相似文献   
87.
88.
In this study, our objective was to evaluating the value of serum zinc levels as an etiologic and prognostic marker in patients with polycystic ovarian syndrome. We conducted a prospective study, including 53 women with polycystic ovarian syndrome and 33 healthy controls. We compared serum zinc levels, as well as clinical and metabolic features, of the cases. We also compared serum zinc levels between patients with polycystic ovarian syndrome with insulin resistance. Mean zinc levels were found to be significantly lower in patients with polycystic ovarian syndrome than healthy controls. Multiple logistic regression analysis of significant metabolic variables between polycystic ovarian syndrome and control groups (serum zinc level, body mass index, the ratio of triglyceride/high-density lipoprotein cholesterol, and homocysteine) revealed that zinc level was the most significant variable to predict polycystic ovarian syndrome. Mean serum zinc levels tended to be lower in patients with polycystic ovarian syndrome with impaired glucose tolerance than patients with normal glucose tolerance, but the difference was not statistically significant. In conclusion, zinc deficiency may play a role in the pathogenesis of polycystic ovarian syndrome and may be related with its long-term metabolic complications.  相似文献   
89.

Background

Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.

Findings

Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [3H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.

Conclusions

These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis.  相似文献   
90.
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