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81.
The effects of yeheb (Cordeauxia
edulis Hemsl.) leaf extract on feeding and oviposition by diamondback moth (DBM) (Plutella xylostella L.) and the behavior of DBM parasitoid, Cotesia vestalis (Haliday), were studied. Volatile organic compounds (VOCs) from the headspace of intact and DBM-damaged broccoli plants sprayed
with yeheb extracts (YE) were also analyzed. Larval feeding and growth, and oviposition by adult DBM were strongly inhibited
by the extract. Cotesia vestalis were attracted to volatile blends from intact or DBM-damaged broccoli plants sprayed with YE over intact plants sprayed with
water or methanol. Analyses of VOCs in the headspace of broccoli plants revealed that both intact and DBM-damaged plants sprayed
with YE showed remarkable differences in sesquiterpene compounds compared to intact control treatments. These combined negative
effects of YE on DBM fitness together with positive effects on the parasitoid show that yeheb is a potential source of compounds
for use in integrated pest management to control damage caused by DBM. 相似文献
82.
Famida G. Hoosain Yahya E. Choonara Pradeep Kumar Lomas K. Tomar Charu Tyagi Lisa C. du Toit Viness Pillay 《AAPS PharmSciTech》2017,18(3):654-670
In this study, an optimized epichlorohydrin-crosslinked semi-interpenetrating polymer network xerogel matrix system (XePoMas) for the controlled delivery of sulpiride was prepared. The ability of XePoMas to sustain drug release was determined by in vitro and in vivo drug release experiments. Swelling of the xerogel over the 24-h experimental period ranged from 346 to 648%; swelling was observed to increase exponentially over the initial 8 h. In vitro drug release depicted a linear zero order drug release profile with an R 2 value of 0.9956. The ability of the fabricated XePoMas to sustain drug release and enhance bioavailability of sulpiride in vivo was investigated by evaluating the plasma drug concentration over 24 h in the large pig model. The optimized XePoMas formulation was shown to increase intestinal absorption of sulpiride to a greater extent than the marketed product in vivo, with a C max of 830.58 ng/mL after 15 h. 相似文献
83.
Jozaa Z. ALTamimi Nora A. AlFaris Dalal H. Aljabryn Reham I. Alagal Ghedeir M. Alshammari Hussain Aldera Sultan Alqahtani Mohammed Abdo Yahya 《Saudi Journal of Biological Sciences》2021,28(8):4300-4310
Diabetes mellitus induces testicular damage, increases sperm abnormalities, and impairs reproductive dysfunction due to induction of endocrine disturbance and testicular oxidative stress. This study evaluated the reproductive protective effect of ellagic acid (EA) against testicular damage and abnormalities in sperm parameters in Streptozotocin (STZ)-induced diabetic rats (T1DM) and examined some possible mechanisms of protection. Adult male rats were segregated into 5 groups (n = 12 rat/each) as control, control + EA (50 mg/kg/day), T1DM, T1DM + EA, and T1DM + EA + brusatol (an Nrf-2 inhibitor) (2 mg/twice/week). All treatments were conducted for 12 weeks, daily. EA preserved the structure of the seminiferous tubules, prevented the reduction in sperm count, motility, and viability, reduced sperm abnormalities, and downregulated testicular levels of cleaved caspase-3 and Bax in diabetic rats. In the control and diabetic rats, EA significantly increased the circulatory levels of testosterone, reduced serum levels of FSH and LH, and upregulated Bcl-2 and all steroidogenic genes (StAr, 3β-HSD1, and 11β-HSD1). Besides, it reduced levels of ROS and MDA but increased levels of GSH and MnSOD and the transactivation of Nrf2. All these biochemical alterations induced by EA were associated with increased activity and nuclear accumulation of Nrf2. However, all these effects afforded by EA were weakened in the presence of brusatol. In conclusion, EA could be an effective therapy to alleviated DM-induced reproductive toxicity and dysfunction in rats by a potent antioxidant potential mediated by the upregulation of Nrf2. 相似文献
84.
Frederick?R.?PreteEmail author Justin?L.?Komito Salina?Dominguez Gavin?Svenson LeoLin?Y.?López Alex?Guillen Nicole?Bogdanivich 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(9):877-894
We assessed the differences in appetitive responses to visual stimuli by three species of praying mantis (Insecta: Mantodea),
Tenodera aridifolia sinensis, Mantis religiosa, and Cilnia humeralis. Tethered, adult females watched computer generated stimuli (erratically moving disks or linearly moving rectangles) that
varied along predetermined parameters. Three responses were scored: tracking, approaching, and striking. Threshold stimulus
size (diameter) for tracking and striking at disks ranged from 3.5 deg (C. humeralis) to 7.8 deg (M. religiosa), and from 3.3 deg (C. humeralis) to 11.7 deg (M. religiosa), respectively. Unlike the other species which struck at disks as large as 44 deg, T. a. sinensis displayed a preference for 14 deg disks. Disks moving at 143 deg/s were preferred by all species. M. religiosa exhibited the most approaching behavior, and with T. a. sinensis distinguished between rectangular stimuli moving parallel versus perpendicular to their long axes. C. humeralis did not make this distinction. Stimulus sizes that elicited the target behaviors were not related to mantis size. However,
differences in compound eye morphology may be related to species differences: C. humeralis’ eyes are farthest apart, and it has an apparently narrower binocular visual field which may affect retinal inputs to movement-sensitive
visual interneurons. 相似文献
85.
Vedat Cinar Yahya Polat Abdulkerim Kasim Baltaci Rasim Mogulkoc 《Biological trace element research》2011,140(1):18-23
This study was performed to assess how 4 weeks of magnesium supplementation and exercise affect the free and total plasma
testosterone levels of sportsmen practicing tae kwon do and sedentary controls at rest and after exhaustion. The testosterone
levels were determined at four different periods: resting before supplementation, exhaustion before supplementation, resting
after supplementation, and exhaustion after supplementation in three study groups, which are as follows: Group 1—sedentary
controls supplemented with 10 mg magnesium per kilogram body weight. Group 2—tae kwon do athletes practicing 90–120 min/day
supplemented with 10 mg magnesium per kilogram body weight. Group 3—tae kwon do athletes practicing 90–120 min/day receiving
no magnesium supplements. The free plasma testosterone levels increased at exhaustion before and after supplementation compared
to resting levels. Exercise also increased testosterone levels relative to sedentary subjects. Similar increases were observed
for total testosterone. Our results show that supplementation with magnesium increases free and total testosterone values
in sedentary and in athletes. The increases are higher in those who exercise than in sedentary individuals. 相似文献
86.
Atri MS Saboury AA Moosavi-Movahedi AA Goliaei B Sefidbakht Y Alijanvand HH Sharifzadeh A Niasari-Naslaji A 《Journal of biomolecular structure & dynamics》2011,28(6):919-928
α-Lactalbumin α-La), together with oleic acid can be converted to a complex, which kills tumor cells selectively. Cytotoxic α-La -oleic acid and α-La -linoleic acid complexes were generated by adding fatty acid to camel holo α-La at 60 ° C (referred to as La-OA-60 and La-LA-60 state, respectively). Structural properties of these complexes were studied and compared to the camel α-La. The experimental results show that linoleic acid induces α-La partial unfolding but oleic acid does not change the protein structure significantly. Also the stability of La-OA-60 and La-LA-60 toward thermal denaturation was measured. The order of temperature at the transition midpoint is as follows: La-LA-60 < La-OA-60 < α-La. La-OA-60 complex inhibited tubulin polymerization in vitro. Although the structures of La-OA-60 and La-LA-60 were different, these two complexes had similar cytotoxic effect to DU145 human prostate cancer cells. Samples of La-OA-60 that have been renatured after denaturation lost the specific biological activity toward tumor cells. 相似文献
87.
Bibi F. Choonara Yahya E. ChoonaraPradeep Kumar Divya BijukumarLisa C. du Toit Viness Pillay 《Biotechnology advances》2014
The oral delivery of proteins and peptides is a dynamic research field despite the numerous challenges limiting their effective delivery. Successful oral delivery of proteins and peptides requires the accomplishment of three key tasks: protection of the macromolecules from degradation in the gastrointestinal tract (GIT), permeation through the intestinal barrier and absorption of molecules into the systemic circulation. Currently, no clinically useful oral formulations have been developed but several attempts have been made to overcome the challenges of low oral bioavailability resulting from poor absorption, poor permeation and enzymatic degradation of the proteins and peptides in the GIT. Present strategies attempt to provide structural protection of the proteins and peptides and improved absorption through the use of enzyme inhibitors, absorption enhancers, novel polymeric delivery systems and chemical modification. However, each of these technologies has their limitations despite showing positive results. This review attempts to discuss the physical and chemical barriers of the GIT with particular emphasis on the current approaches employed to overcome these barriers, including the evaluation of other non-parenteral routes of protein and peptide delivery. In addition, this review assimilates oral formulation strategies under development and within the clinical trial stage in relation to their benefits and drawbacks with regard to facilitating optimal protection and absorption of proteins and peptides, as well as pertinent future challenges and opportunities governing oral drug delivery. 相似文献
88.
Determining the quality and complexity of next-generation sequencing data without a reference genome
Seyed Yahya Anvar Lusine Khachatryan Martijn Vermaat Michiel van Galen Irina Pulyakhina Yavuz Ariyurek Ken Kraaijeveld Johan T den Dunnen Peter de Knijff Peter AC ’t Hoen Jeroen FJ Laros 《Genome biology》2014,15(12)
We describe an open-source kPAL package that facilitates an alignment-free assessment of the quality and comparability of sequencing datasets by analyzing k-mer frequencies. We show that kPAL can detect technical artefacts such as high duplication rates, library chimeras, contamination and differences in library preparation protocols. kPAL also successfully captures the complexity and diversity of microbiomes and provides a powerful means to study changes in microbial communities. Together, these features make kPAL an attractive and broadly applicable tool to determine the quality and comparability of sequence libraries even in the absence of a reference sequence. kPAL is freely available at https://github.com/LUMC/kPAL.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0555-3) contains supplementary material, which is available to authorized users. 相似文献89.
90.
Bahaa-eldin E. Abdel Rahim Mohamed Salih Mahfouz Umar Yagoub Yahya M. H. Solan Rashad Mohammed Alsanosy 《PloS one》2014,9(4)