Effects of beer and hop on ionotropic gamma-aminobutyric acid receptors     

Aoshima H  Takeda K  Okita Y  Hossain SJ  Koda H  Kiso Y 《Journal of agricultural and food chemistry》2006,54(7):2514-2519

Beer induced the response of the ionotropic gamma-aminobutyric acid receptors (GABA(A) receptors) expressed in Xenopus oocytes, indicating the presence of gamma-aminobutyric acid (GABA)-like activity. Furthermore, the pentane extract of the beer, hop (Humulus lupulus L.) oil, and myrcenol potentiated the GABA(A) receptor response elicited by GABA. The GABA(A) receptor responses were also potentiated by the addition of aliphatic esters, most of which are reported to be present in beer flavor. Aliphatic esters showed the tendency to decrease in the potentiation of the GABA(A) receptor response with an increase in their carbon chain length. When myrcenol was injected to mice prior to intraperitoneal administration of pentobarbital, the pentobarbital-induced sleeping time of mice increased additionally. Therefore, the beer contained not only GABA-like activity but also the modulator(s) of the GABA(A) receptor response.  相似文献   

Nitric oxide level in seminal plasma and its relation with sperm DNA damages     

Amiri I  Sheikh N  Najafi R 《Iranian Biomedical Journal》2007,11(4):259-264

BACKGROUND: Evidence supports the involvement of nitric oxide (NO) in a variety of male reproductive processes such as spermatogenesis, spermiogenesis, sperm motion, sperm metabolism and sperm capacitation. However, low concentration of NO is essential in biology and physiology of spermatozoa, but high amounts of NO is toxic and has negative effects on sperm functions. On the other hand, it is established that high amounts of NO have detrimental effects on DNA. The integrity of sperm DNA is an important factor in successful fertility and embryo development. It is hypothesized that supra physiological concentrations of NO in seminal plasma cause sperm DNA damage. The aim of this study was to determine sperm DNA damage by comet assay and its correlation with NO level in seminal plasma of fertile and infertile men. METHODS: Semen samples were collected from 45 patients and 70 healthy donors. The stable metabolites of NO (nitrite and nitrate) in seminal plasma were measured by Griess assay and DNA damage was determined using single cell gel electrophoresis (comet) assay method. RESULTS: The NO concentration in the seminal plasma of infertile males was significantly higher than fertile males (5.74+/-1.01 microM/L vs. 3.88+/-0.53 microM/L). There was a significant positive correlation between the NO concentration and sperm DNA comet value in infertile males (P<0.01, R=0.598). CONCLUSION: These results indicate that the overproduction of NO in genital tract of infertile males has a potential pathogenetic role in the reduction of sperm DNA integrity.  相似文献   

Baseline susceptibility of a wild strain of Phlebotomus papatasi (Diptera: Psychodidae) to DDT and pyrethroids in an endemic focus of zoonotic cutaneous leishmaniasis in Iran     

Saeidi Z  Vatandoost H  Akhavan AA  Yaghoobi-Ershadi MR  Rassi Y  Sheikh Z  Arandian MH  Jafari R  Sanei Dehkordi AR 《Pest management science》2012,68(5):669-675

BACKGROUND: Phelebotumus papatsi is considered to be the main vector of zoonotic cutaneous leishmaniasis as well as sand fly fever in Iran. There are several measures for vector control, with emphasis on insecticides. The objective of this study was to determine the baseline susceptibility of this vector to the commonly used insecticides in an endemic focus of the disease in central Iran. P. papatasi collected from the field were used for susceptibility status. Its baseline susceptibility to DDT and pyrethroids was assessed on about 6866 specimens collected from Badrood rural district, Esfahan Province, Iran, during the summer of 2010. The LT₅₀ and LT₉₀ values were measured according to the World Health Organisation (WHO) test using probit analysis and regression lines. RESULTS: Results of tests against female P. papatasi revealed LT₅₀ values to DDT 4%, permethrin 0.75%, deltamethrin 0.1%, cyfluthrin 0.15% and lambdacyhalothrin 0.05% of 1104.97, 182.35, 26.79, 15.42 and 1.48 s respectively. The figures for male P. papatasi were 973.51, 59.5, 4.4, 2.65 and 1.5. CONCLUSION: The results of this study provide a guideline for implementation of different vector control measures. Furthermore, guidelines are needed for monitoring and evaluation of insecticide susceptibility tests against sand flies. Copyright © 2012 Society of Chemical Industry  相似文献   

Water buffalo and cattle ranching in the Lower Amazon Basin: Comparisons and conflicts     

Pervaze A. Sheikh  Frank D. Merry  David G. McGrath 《Agricultural Systems》2006

From 1975 to 2000, the water buffalo population in the Brazilian Amazon increased at nearly 13% per year, making it one of the fastest growing herds in the world. On the floodplains of the Amazon River buffalo are managed in a similar manner to cattle, but often earn superior production figures. This production advantage, however, is tempered by the role buffalo play in conflicts between landowners; buffalo are prone to altering the floodplain environment and interfering with production activities such as fishing and farming. In this research, we show that buffalo are kept on the floodplains 24% longer than cattle throughout the year, and 37% longer than cattle during periods when landowner conflicts are most likely to occur. We also show that buffalo productivity is greater than cattle in this system, which gives an opportunity to design management regimes for buffalo that may increase production costs, but that will lower the environmental and social problems that involve buffalo. Specifically, when the waters begin to rise, buffalo should be removed from the floodplains at the same time as cattle. Although this will not lessen the damage done while the buffalo is on the floodplain, it will place buffalo on the floodplain during the dry season when the erosion potential is at its lowest, and reduce the time that buffalo may interfere with other production activities such as fishing. The additional production costs incurred by early removal will not dissipate the production advantage over cattle. Without specific management that addresses the socio-economic and environmental problems caused by buffalo, the continued high growth rate for the buffalo population on the Amazon floodplains may not be sustainable and conflicts will become commonplace.  相似文献   

Global mapping of the yeast genetic interaction network   总被引：1，自引：0，他引：1  

Tong AH  Lesage G  Bader GD  Ding H  Xu H  Xin X  Young J  Berriz GF  Brost RL  Chang M  Chen Y  Cheng X  Chua G  Friesen H  Goldberg DS  Haynes J  Humphries C  He G  Hussein S  Ke L  Krogan N  Li Z  Levinson JN  Lu H  Ménard P  Munyana C  Parsons AB  Ryan O  Tonikian R  Roberts T  Sdicu AM  Shapiro J  Sheikh B  Suter B  Wong SL  Zhang LV  Zhu H  Burd CG  Munro S  Sander C  Rine J  Greenblatt J  Peter M  Bretscher A  Bell G  Roth FP  Brown GW  Andrews B  Bussey H  Boone C 《Science (New York, N.Y.)》2004,303(5659):808-813

A genetic interaction network containing approximately 1000 genes and approximately 4000 interactions was mapped by crossing mutations in 132 different query genes into a set of approximately 4700 viable gene yeast deletion mutants and scoring the double mutant progeny for fitness defects. Network connectivity was predictive of function because interactions often occurred among functionally related genes, and similar patterns of interactions tended to identify components of the same pathway. The genetic network exhibited dense local neighborhoods; therefore, the position of a gene on a partially mapped network is predictive of other genetic interactions. Because digenic interactions are common in yeast, similar networks may underlie the complex genetics associated with inherited phenotypes in other organisms.  相似文献   

Multi-scale processes influencing global carbon storage and land-carbon-climate nexus: A critical review     

Owais Ali WANI  Shamal Shasang KUMAR  Nazir HUSSAIN  Anas Ibni Ali WANI  Subhash BABU  Parvej ALAM  Megna RASHID  Simona Mariana POPESCU  Sheikh MANSOOR 《土壤圈》2023,33(2):250-267

Carbon(C) is a key constitutive element in living organisms(plants, microbes, animals, and humans). Carbon is also a basic component of agriculture because it plays a dynamic role in crop growth, development, nutrient cycling, soil fertility, and other agricultural features. The presence of C enhances soil physical, chemical, and biological properties. The C cycle supports all life on the Earth by transferring C between living organisms and the environment. The global climate is changing, and th...  相似文献   

EFFECTS OF DIFFERENT NITROGEN,PHOSPHORUS, POTASSIUM RATES ON THE QUALITY AND QUANTITY OF CITRUS PLANTS,VARIETY THOMSON NOVEL UNDER RAINFED AND IRRIGATED CONDITIONS     

A. Sheikh Ashkevari  S. H. Hoseinzadeh  M. Miransari 《Journal of plant nutrition》2013,36(9):1412-1423

Plants require nutrients including nitrogen (N), phosphorus (P), and potassium (K) for their growth and production. Although there have been previously extensive research work regarding the effects of NPK on plant growth, data related to the effects of long term application of NPK on the quality and quantity of citrus under rainfed and irrigated conditions are little. Accordingly, such effects were evaluated in this research work using different chemical fertilization factorially combined and on the basis of a completely randomized block design. Using ammonium sulfate (100, 150 and 200 g tree ^{? 1}), triple super phosphate (0, 25, 50, and 75 g tree^?1) and potassium sulfate (0, 50, 100, 150 g tree ^{? 1}) the quantity and quality of citrus fruit, variety Thomson were determined in a 10-year experiment in two different research stations in Ramsar, Iran. NPK fertilization significantly affected the quality and quantity of citrus fruits, indicating the significance of NPK fertilization for citrus production.  相似文献   

Fabrication of poly(caprolactone) nanofibers containing hydroxyapatite nanoparticles and their mineralization in a simulated body fluid     

Muzafar A. Kanjwal  Faheem A. Sheikh  R. Nirmala  Javier Macossay  Hak Yong Kim 《Fibers and Polymers》2011,12(1):50-56

In the present study, we introduce poly(caprolactone) (PCL) nanofibers that contain hydroxyapatite (HAp) nanoparticles (NPs) as a result of an electrospinning process. A simple method that does not depend on additional foreign chemicals has been employed to synthesize HAp NPs through calcination of bovine bones. Typically, a colloidal gel consisting of PCL/HAp has been electrospun to form nanofibers. Physiochemical aspects of prepared nanofibers were characterized for FE-SEM, TEM, XRD and FTIR which confirmed nanofibers were well-oriented and had good dispersion of HAp NPs. Parameters affecting the utilization of the prepared nanofibers in various nano-biotechnological fields have been studied; for instance, the bioactivity of the produced nanofiber mats was investigated while incubated with stimulated body fluid (SBF). The results from incubation of nanofibers in SBF indicate that incorporation of HAp strongly activates precipitation of the apatite-like materials because the HAp NPs act as seeds that accelerate crystallization of the biological HAp from the utilized SBF.  相似文献   

Allelopathic potential of indigenous Bangladeshi rice varieties          下载免费PDF全文

Sheikh M. Masum  Mohammad Amzad Hossain  Hikaru Akamine  Jun‐Ichi Sakagami  Prasanta C. Bhowmik 《Weed Biology and Management》2016,16(3):119-131

A series of experiments was conducted in the laboratory and greenhouse of the Subtropical Field Science Center, University of the Ryukyus, Japan, from April to October 2015 to assess the allelopathic potential of 50 indigenous Bangladeshi rice varieties by using the donor–receiver bioassay, equal compartment agar method (ECAM), plant residue extract method and pot culture method. Lettuce (Lactuca sativa L.), cress (Lepidium sativum L.), radish (Raphanus sativus L.), barnyard grass (Echinochloa crus‐galli L. Beauv.) and jungle rice (Echinochloa colona L.) were used as the test plants. The highest inhibition effect was given by Boterswar, while the stimulating effect was given by Kartikbalam and Panbira in the donor–receiver bioassay and ECAM tests. Boterswar, Goria, Biron and Kartiksail were selected as the highest allelopathic‐potential varieties by the donor–receiver bioassay and ECAM. In the methanol extract test, Boterswar gave the strongest inhibitory effect on both barnyard grass and jungle rice, while Kartiksail gave the highest inhibitory effect on the jungle rice shoot. The growth parameters and total dry matter of barnyard grass in the greenhouse pot experiment were significantly reduced as a result of the application of aqueous extracts of the selected rice varieties, which was similar to the results of the laboratory experiments. The varieties of Boterswar, Goria, Biron and Kartiksail were selected as the most allelopathic among the 50 indigenous Bangladeshi rice varieties. These rice varieties could be used for the isolation and identification of allelochemicals and to further develop new varieties that are tolerant to weeds.  相似文献   

Synthesis and characterization of new copolymers from glycidyl methacrylate and tetrahydrofurfuryl acrylate: Determination of reactivity ratios     

Ahmad Danial Azzahari  Rosiyah Yahya  Aziz Hassan  Md. Rezaul Karim Sheikh 《Fibers and Polymers》2012,13(5):555-563

The new copolymers from different feed compositions of glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesized using free radical polymerization in toluene at 70±1 °C using benzoyl peroxide (BPO) as initiator. The polymers were characterized by ¹H NMR, ¹³C NMR and FTIR spectroscopic techniques. The polydispersities of the copolymers suggest a strong tendency for chain termination by disproportionation. The glass transition temperature of the copolymers increases with increase in GMA content. The thermal stability of the copolymers increases with increase in THFA content. The copolymer compositions were determined using ¹H NMR analysis. Reactivity ratios for GMA and THFA as determined by the Mao-Huglin method were r₁=0.379 and r₂=0.266. The results showed that all these copolymerizations are strictly linear systems describable by the Mayo-Lewis equation based on the terminal model and that accurate reactivity ratio data can be obtained.  相似文献