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171.
172.
Balaydın HT Soyut H Ekinci D Göksu S Beydemir S Menzek A Sahin E 《Journal of enzyme inhibition and medicinal chemistry》2012,27(1):43-50
(2-Bromo-3,4-dimethoxyphenyl) (3,4-dimethoxyphenyl)methanone (10) and its derivatives with Br, one dibromide and isomeric three tribromides, were synthesized. Demethylation of these compounds afforded a series of new bromophenols. Inhibition of human cytosolic carbonic anhydrase II (hCA II) isozyme by these new bromophenols and naturally occurring 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (3), and 5,5'-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (4) was investigated. The synthesized compounds showed carbonic anhydrase inhibitory capacities with IC(50) values in the range of 0.7-372 μM against hCA II. Some bromophenols investigated here showed effective hCA II inhibitory activity and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, or osteoporosis. 相似文献
173.
Aruna Govindaraju Alper Uzun LaShonda Robertson Mehmet O Atli Abdullah Kaya Einko Topper Elizabeth A Crate James Padbury Andy Perkins Erdogan Memili 《Reproductive biology and endocrinology : RB&E》2012,10(1):1-10
Background
Degenerative effects of critical regulators of reproduction, the kisspeptin peptides, on cellular aspects of sexually immature male gonads are known but similar information on accessory sex glands remain elusive.Methods
Prepubertal laboratory rats were injected kisspeptin-10 at three different dosage concentrations (10 pg, 1 ng and 1 microgram) for a period of continuous 12 days at the rate of two doses per day. Control rats were maintained in parallel. The day following the end of the experimental period, seminal vesicles were removed and processed for light and electron microscopic examination using the standard methods. DNA damage was estimated by DNA ladder assay and DNA fragmentation assay.Results
The results demonstrated cellular degeneration. Epithelial cell height of seminal vesicles decreased significantly at all doses (P < 0.05). Marked decrease in epithelial folds was readily noticeable, while the lumen was dilated. Ultrastructural changes were characterized by dilatation of endoplasmic reticulum and Golgi complex, heterochromatization of nuclei, invagination of nuclear membranes and a decreased number of secretory granules. Percent DNA damage to the seminal vesicle was 19.54 +/- 1.98, 38.06 +/- 2.09 and 58.18 +/- 2.59 at 10 pg, 1 ng and 1 microgram doses respectively.Conclusion
The study reveals that continuous administration of kisspeptin does not lead to an early maturation but instead severe degeneration of sexually immature seminal vesicles. 相似文献174.
Alev?AtisEmail author Yavuz?Aydin Filiz?Ciftci Damlanur?Sak?z Abdullah?Arslan Ak?n?S?Toklu Melahat?Donmez Nimet?Goker 《Reproductive biology and endocrinology : RB&E》2012,10(1):11
Background
In this study, we investigated the effect of hyperbaric oxygen therapy (HBOT) on the morphology of estradiol valerate (EV) induced polycystic ovary (PCO) to find a new treatment modality for improvement of PCO. 相似文献175.
Yang X Abdullah AS Wei B Jiang J Deng W Qin B Yan W Wang Q Zhong C Wang Q Ruan Y Zou Y Xie P Wei F Xu N Liang H 《PloS one》2012,7(1):e30198
Background
Male circumcision (MC) has been shown to reduce the risk of female to male transmission of HIV. The goal of this survey was to explore the acceptability of MC among the Chinese and to identify factors associated with circumcision preference.Methods
A cross-sectional survey was conducted between September 2009 and December 2010. We interviewed 2,219 male community participants, from three high HIV prevalence provinces in western China. A structured questionnaire was used to collect data on MC knowledge, willingness to accept MC, reasons to accept or refuse MC, and sexual behaviors and health. For those who refused MC, a health education intervention providing information on the benefits of circumcision was conducted. We used multiple logistic regression models to identify factors associated with the acceptability of MC.Results
Of the respondents (n = 2,219), 44.6% (989/2,219) reported they would accept MC for the following reasons: promotion of female partners'' hygiene (60.3%), redundant foreskin (59.4%), prevention of penile cancer (50.2%), enhanced sexual pleasure (41.4%), and protection against HIV and STDs (34.2%). The multivariable logistic regression showed that five factors were associated with MC willingness: long foreskin (OR = 15.98), residing in Xinjiang province (OR = 3.69), being younger than 25 (OR = 1.60), knowing hazards of redundant foreskin (OR = 1.78), and having a friend who underwent circumcision (OR = 1.36).Conclusion
The acceptability of male circumcision was high among the general population in China. Our study elucidates the factors associated with circumcision preference and suggests that more health education campaigns about positive health effects are necessary to increase the MC rate in China. 相似文献176.
177.
Hyacinth HI Gee BE Adamkiewicz TV Adams RJ Kutlar A Stiles JK Hibbert JM 《Cytokine》2012,60(1):302-308
Sickle cell anemia (SCA) associated cerebrovascular disease includes vascular remodeling, abnormal cerebral blood flow (CBF) and infarction. We studied the relationships between plasma brain derived neurotropic factor (BDNF), platelet derived growth factors (PDGF-AA and -AB/BB) and high trans-cranial Doppler (TCD) velocity, an indication of CBF velocity. Baseline plasma samples from 39 children (19 SCA with abnormal/high TCD [SATCD], 13 SCA with normal TCD [SNTCD] and 7 healthy non-SCA), were assayed for BDNF, PDGF-AA and -AB/BB plus 11 other cytokines. The sensitivity, specificity and usefulness of these biomarkers for stroke prediction was investigated. All subject groups were of similar age and gender distribution. Mean BDNF was significantly higher among SATCD than SNTCD (p=0.004) as was mean PDGF-AA (p=0.001). Similarly, mean PDGF-AA was higher among SCA subjects who developed stroke than those who did not (p=0.012). Elevated BDNF and PDGF-AA were good predictors of the presence of abnormally high CBF velocity and were both associated with severity of anemia. Elevated PDGF-AA predicted risk for stroke development. Stroke incidence and high TCD velocity were associated with elevated BDNF and PDGF-AA. These findings suggest a role for BDNF and PDGF-AA in the patho-physiological mechanism of cerebrovascular disease in SCA. 相似文献
178.
179.
The ground state geometries have been computed by using density functional theory. The excitation energies for dye sensitizers were performed by using time dependant density functional theory. The polarizable continuum model (PCM) has been used for evaluating bulk solvent effects at all stages. The calculations have been carried out in methanol according to the experimental set up. The long-range-corrected functional (PCM-TD-LC-BLYP) underestimate the absorption spectrum of parent molecule while PCM-TDBHandHLYP is in good agreement with the experimental data. The highest occupied molecular orbital (HOMO) is delocalized on TPA moiety while lowest unoccupied molecular orbital (LUMO) is localized on anchoring group, conjugated chain and the benzene ring near to the anchoring group. The LUMO energies of all the investigated dyes are above the conduction band of TiO(2), HOMOs are below the redox couple and HOMO-LUMO energy gaps of studied dyes are smaller compared to TC4. The 1 and 3 are 7 and 12?nm blue shifted while 2 and 4 are 25 and 22?nm red shifted, respectively compared to TC4. The trend of electron injection (ΔG(inject)), relative electron injection (ΔG (r) (inject) ()), and electronic coupling constant (|VRP|) has been observed as 3?>?1?>?4?>?2?>?TC4. The improved ΔG(inject), |VRP| and light harvesting efficiency (LHE) of new designed sensitizers revealed that these materials would be excellent sensitizers. The broken coplanarity between the benzene near anchoring group having LUMO and the last benzene attached to TPA unit in 1-4 consequently would hamper the recombination reaction. 相似文献
180.
Proteases are one of the highest value commercial enzymes as they have broad applications in food, pharmaceutical, detergent, and
dairy industries and serve as vital tools in determination of structure of proteins and polypeptides. Multiple application of these
enzymes stimulated interest to discover them with novel properties and considerable advancement of basic research into these
enzymes. A broad understanding of the active site of the enzyme and of the mechanism of its inactivation is essential for
delineating its structure-function relationship. Primary structure analysis of alkaline protease showed 42% of its content to be alpha
helix making it stable for three dimensional structure modeling. Homology model of alkaline protease has been constructed using
the X-ray structure (3F7O) as a template and swiss model as the workspace. The model was validated by ProSA, SAVES,
PROCHECK, PROSAII and RMSD. The results showed the final refined model is reliable. It has 53% amino acid sequence identity
with the template, 0.24 Å as RMSD and has -7.53 as Z-score, the Ramachandran plot analysis showed that conformations for 83.4 %
of amino acid residues are within the most favored regions and only 0.4% in the disallowed regions. 相似文献