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91.
Feverfew (Tanacetum parthenium) (TP) is a valuable medicinal plant from Asteraceae family with various pharmaceutical and therapeutic properties. A pot experiment was conducted to evaluate the effect of salicylic acid (SA) on the physiological and morphological responses of TP under salinity stress. Salinity was induced by NaCl and CaCl2 (2:1) at 30, 60, 90, 120, 150 and 180 mM levels. SA was applied as foliar application at 0, 200 and 300 ppm concentrations. Plant height, leaf and shoot number, fresh and dry weight and essential oil, starch, sugar, protein, proline, catalase (CAT), peroxidase (POD), and ascorbic peroxidase (APX) contents were as measured morpho-physiological traits. The results showed that SA significantly (P ≤ 0.05) improved the measured traits and caused higher tolerance in TP plants under salinity stress. The essential oil content increased with increasing the salinity level up to 90 mM, which was more significant when combined with SA application. All of the measured traits except proline content, antioxidant enzymes, essential oil and sugar decreased at high salinity levels. 相似文献
92.
Ankita Salvi Pratik Bankhele Jamal M. Jamil Madhura Kulkarni-Chitnis Ya Fatou Njie-Mbye Sunny E. Ohia Catherine A. Opere 《Neurochemical research》2016,41(5):1020-1028
In the present study, we investigated the effect of three different sources of hydrogen sulfide (H2S) on sympathetic neurotransmission from isolated superfused bovine iris-ciliary bodies. The three agents under consideration were: ACS67, a hybrid of latanoprost and a H2S-donating moiety; l-cysteine, a substrate for endogenous production of H2S and GYY 4137, a slow donor of H2S. We also examined the contribution of prostaglandins to the pharmacological actions of the H2S donors on release of [3H]-norepinephrine ([3H]NE) triggered by electrical field stimulation. ACS67, l-cysteine and GYY 4137 caused a concentration-dependent inhibition of electrically-evoked [3H]NE release from isolated bovine iris-ciliary bodies without affecting basal [3H]NE efflux. The cyclooxygenase inhibitor, flurbiprofen enhanced the inhibitory action of ACS67 and l-cysteine on stimulated [3H]NE release. Both aminooxyacetic acid, an inhibitor of cystathionine-β-synthase and glibenclamide, a KATP channel blocker reversed the inhibition of evoked NE release induced by the H2S donors. We conclude that H2S donors can inhibit sympathetic neurotransmission from isolated bovine iris-ciliary bodies, an effect partially dependent on the in situ production of H2S and prostanoids, and is mediated by an action on KATP channels. 相似文献
93.
94.
Linkage analysis narrows the critical region for oculodentodigital dysplasia to chromosome 6q22-q23.
S A Boyadjiev E W Jabs M LaBuda J E Jamal T Torbergsen L J Ptácek R C Rogers R Nyberg-Hansen S Opjordsmoen C B Zeller O C Stine H J Stalker R T Zori R E Shapiro 《Genomics》1999,58(1):34-40
Oculodentodigital dysplasia (ODDD) is an autosomal dominant condition with high penetrance and variable expressivity. The anomalies of the craniofacial region, eyes, teeth, and limbs indicate abnormal morphogenesis during early fetal development. Neurologic abnormalities occur later in life and appear to be secondary to white matter degeneration and basal ganglia changes. In familial cases, the dysmorphic and/or neurodegenerative components of the phenotype can be more severe and/or present at a younger age in subsequent generations, suggesting genetic anticipation. These clinical features suggest that the ODDD gene is pleiotropic with important functions throughout pre- and postnatal development. We have performed two-point linkage analysis with seven ODDD families and 19 microsatellite markers on chromosome 6q spanning a genetic distance of approximately 11 cM in males and 20 cM in females. We have refined the location of the ODDD gene between DNA markers D6S266/D6S261 (centromeric) and D6S1639 (telomeric), an interval of 1.01 (male) to 2.87 (female) cM. The strongest linkage was to DNA marker D6S433 (Zmax = 8.96, thetamax = 0.001). Families show significant linkage to chromosome 6q22-q23 and no evidence for genetic heterogeneity. 相似文献
95.
Farhana Bibi Humaira Yasmin Asif Jamal Mohammad S. AL-Harbi Mushtaq Ahmad Muhammad Zafar Bashir Ahmad Bassem N. Samra Atef F. Ahmed Muhammad Ishtiaq Ali 《Saudi Journal of Biological Sciences》2021,28(12):7595
Microalgae biomass is considered an important feedstock for biofuels and other bioactive compounds due to its faster growth rate, high biomass production and high biomolecules accumulation over first and second-generation feedstock. This research aimed to maximize the specific growth rate of fresh water green microalgae Closteriopsis acicularis, a member of family Chlorellaceae under the effect of pH and phosphate concentration to attain enhanced biomass productivity. This study investigates the individual and cumulative effect of phosphate concentration and pH on specific growth characteristics of Closteriopsis acicularis in autotrophic mode of cultivation for bioethanol production. Central-Composite Design (CCD) strategy and Response Surface Methodology (RSM) was used for the optimization of microalga growth and ethanol production under laboratory conditions. The results showed that high specific growth rate and biomass productivity of 0.342 day−1 and 0.497 g L−1 day−1 respectively, were achieved at high concentration of phosphate (0.115 g L−1) and pH (9) at 21st day of cultivation. The elemental composition of optimized biomass has shown enhanced elemental accumulation of certain macro (C, O, P) and micronutrients (Na, Mg, Al, K, Ca and Fe) except for nitrogen and sulfur. The Fourier transform infrared spectroscopic analysis has revealed spectral peaks and high absorbance in spectral range of carbohydrates, lipids and proteins, in optimized biomass. The carbohydrates content of optimized biomass was observed as 58%, with 29.3 g L−1 of fermentable sugars after acid catalyzed saccharification. The bioethanol yield was estimated as 51 % g ethanol/g glucose with maximum of 14.9 g/L of bioethanol production. In conclusion, it can be inferred that high specific growth rate and biomass productivity can be achieved by varying levels of phosphate concentration and pH during cultivation of Closteriopsis acicularis for improved yield of microbial growth, biomass and bioethanol production. 相似文献
96.
97.
Cheung AM Tile L Lee Y Tomlinson G Hawker G Scher J Hu H Vieth R Thompson L Jamal S Josse R 《PLoS medicine》2008,5(10):e196-12
Background
Vitamin K has been widely promoted as a supplement for decreasing bone loss in postmenopausal women, but the long-term benefits and potential harms are unknown. This study was conducted to determine whether daily high-dose vitamin K1 supplementation safely reduces bone loss, bone turnover, and fractures.Methods and Findings
This single-center study was designed as a 2-y randomized, placebo-controlled, double-blind trial, extended for earlier participants for up to an additional 2 y because of interest in long-term safety and fractures. A total of 440 postmenopausal women with osteopenia were randomized to either 5 mg of vitamin K1 or placebo daily. Primary outcomes were changes in BMD at the lumbar spine and total hip at 2 y. Secondary outcomes included changes in BMD at other sites and other time points, bone turnover markers, height, fractures, adverse effects, and health-related quality of life. This study has a power of 90% to detect 3% differences in BMD between the two groups. The women in this study were vitamin D replete, with a mean serum 25-hydroxyvitamin D level of 77 nmol/l at baseline. Over 2 y, BMD decreased by −1.28% and −1.22% (p = 0.84) (difference of −0.06%; 95% confidence interval [CI] −0.67% to 0.54%) at the lumbar spine and −0.69% and −0.88% (p = 0.51) (difference of 0.19%; 95% CI −0.37% to 0.75%) at the total hip in the vitamin K and placebo groups, respectively. There were no significant differences in changes in BMD at any site between the two groups over the 2- to 4-y period. Daily vitamin K1 supplementation increased serum vitamin K1 levels by 10-fold, and decreased the percentage of undercarboxylated osteocalcin and total osteocalcin levels (bone formation marker). However, C-telopeptide levels (bone resorption marker) were not significantly different between the two groups. Fewer women in the vitamin K group had clinical fractures (nine versus 20, p = 0.04) and fewer had cancers (three versus 12, p = 0.02). Vitamin K supplements were well-tolerated over the 4-y period. There were no significant differences in adverse effects or health-related quality of life between the two groups. The study was not powered to examine fractures or cancers, and their numbers were small.Conclusions
Daily 5 mg of vitamin K1 supplementation for 2 to 4 y does not protect against age-related decline in BMD, but may protect against fractures and cancers in postmenopausal women with osteopenia. More studies are needed to further examine the effect of vitamin K on fractures and cancers. Trial registration: ClinicalTrials.gov (#) and Current Controlled Trials ( NCT00150969#ISRCTN61708241) 相似文献98.
Malik S.Y. Haddadin Jamal Haddadin Omar I. Arabiyat Butros Hattar 《Bioresource technology》2009,100(20):4773-4782
Olive pomace was composted by using a reactor for a period of 50 days in four bioreactors. Urea was added to adjust C/N ration between 25–30. At the end of 50 days of composting using Trichoderma harzianum and Phanerochaete chrysosporium, cellulose and lignin were highly degraded. It was found that after 30 days, P. chrysosporium and T. harzianum degraded approximately 71.9% of the lignin and 59.25% of the cellulose, respectively. The percent of ash content in the raw waste mixture was 13%. This percentage increased from 13% to 18.55% in treatment bioreactors and from 13% to 13.55% in control reactors during 50 day of composting process. The amount of CO2 produced by the treated sample was 3 mg of CO2/g organic carbon which is indicated that the treated sample was considered as stable compost. The results proved that the use of accelerating agents was found to be efficient in producing mature stable with nearly non-phytotoxicity compared to control sample in less than 50 days. 相似文献
99.
Almost all protein-coding genes are spliced and their majority is alternatively spliced. Alternative splicing is a key element in eukaryotic gene expression that increases the coding capacity of the human genome and an increasing number of examples illustrates that the selection of wrong splice sites causes human disease. A fine-tuned balance of factors regulates splice site selection. Here, we discuss well-studied examples that show how a disturbance of this balance can cause human disease. The rapidly emerging knowledge of splicing regulation now allows the development of treatment options. 相似文献
100.
In vitro oxidative metabolism study of (-)-rhazinilam 总被引:1,自引:0,他引:1
Décor A Bellocq D Thoison O Lekieffre N Chiaroni A Ouazzani J Cresteil T Guéritte F Baudoin O 《Bioorganic & medicinal chemistry》2006,14(5):1558-1564
Metabolism studies were conducted in order to investigate the reasons for the in vivo lack of activity of (-)-rhazinilam 1, an original poison of the mitotic spindle. Bioconversion by Beauveria bassiana strains, rat and human liver microsomes allowed the identification of metabolites 2, 3, and 4 oxidized in positions 3 and 5 of rhazinilam. Further experiments indicated that CYP2B6 was the main CYP responsible for the oxidation of 1 by human liver microsomes. All isolated metabolites were markedly less active than rhazinilam in vitro, which might explain its in vivo inactivity. 相似文献