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301.
Bhatti HN Asgher M Abbas A Nawaz R Sheikh MA 《Journal of agricultural and food chemistry》2006,54(13):4617-4623
The present investigation deals with purification and thermal characterization of an acid invertase produced by Fusarium solani in submerged culture. The maximum enzyme activity (9.90 U mL(-1)) was achieved after 96 h of cultivation at pH 5.0 and 30 degrees C in a basal medium containing molasses (2%) as the carbon and energy source supplemented with 1% peptone. Invertase was purified by ammonium sulfate fractionation and column chromatography on DEAE-cellulose and Sephadex G-200. The purified enzyme was proven to be homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular mass of the enzyme was 65 kDa. The optimum pH and temperature for activity were 2.6 and 50 degrees C, respectively. The Km value for sucrose was 3.57 mM with an activation energy of 4.056 kJ mol(-1). Enthalpies of activation (DeltaH) were decreased while entropies (DeltaS) of activation increased at higher temperatures. The effects of alpha-chymotrypsin and 4 M urea were tetraphasic with periodic gain and loss of enzyme activity. A possible explanation for the thermal inactivation of invertase at higher temperatures is also discussed. 相似文献
302.
Samoylenko V Zhao J Dunbar DC Khan IA Rushing JW Muhammad I 《Journal of agricultural and food chemistry》2006,54(17):6398-6402
Morinda citrifolia L. (Rubiaceae), known as noni, has a long history of traditional use in the Hawaiian and Tahitian islands. More recently, an array of commercial noni fruit juice products are gaining popularity as dietary supplements, with claims of anticancer and immunostimulant activities. The biologically active principles of noni are not fully known. In continuation of work on the isolation of markers from dietary supplements, this paper reports the isolation of three new markers, namely, 1-O-(3'-methylbut-3'-enyl)-beta-D-glucopyranose (1), 1-n-butyl-4-(5'-formyl-2'-furanyl)methyl succinate (2), and 4-epi-borreriagenin (3), together with the known iridoid glycosides asperulosidic acid (4) and deacetylasperulosidic acid (5) and a mixture of 1-n-butyl-4-methyl-2-hydroxysuccinate (6a) and 1-n-butyl-4-methyl-3-hydroxysuccinate (6b), as well as a mixture of alpha- and beta-glucopyranose from noni fruit juice obtained from Puerto Rico. The structures of compounds were based on 1H and 13C NMR, mainly 2D NMR COSY, HMQC, HMBC, and NOESY experiments, and HRMS. Furthermore, samples from fresh-squeezed noni fruit juice from Japan revealed the presence of scopoletin (7), in addition to compounds 1-6, indicating no significant differences in the marker constituents of noni collected from Atlantic and Pacific regions. 相似文献
303.
We identified clinical disorders of all 200 city-dwelling cart pulling male camels attending the Veterinary Teaching Hospital, University of Agriculture, Faisalabad, Pakistan during a 7-year period (1993–1999). Data were collected prospectively on a predesigned form and collated. Diagnoses of different diseases/disorders were based on clinical examination supplemented with relevant laboratory tests. A total of 463 entries of 34 different clinical diseases/disorders were recorded. Sarcoptic mange (35% of 200 camels) followed by anhidrosis (23%) and trypanosomosis (19%) were the three most frequently encountered disorders. The body system most often involved was the integument (31%) followed by gastrointestinal (21%), locomotory (12%), thermoregulatory (6%), blood (6%), urogenital (6%), lymphatic (3%), nervous (3%), respiratory (3%) and ocular (3%). 相似文献
304.
Auton A Fledel-Alon A Pfeifer S Venn O Ségurel L Street T Leffler EM Bowden R Aneas I Broxholme J Humburg P Iqbal Z Lunter G Maller J Hernandez RD Melton C Venkat A Nobrega MA Bontrop R Myers S Donnelly P Przeworski M McVean G 《Science (New York, N.Y.)》2012,336(6078):193-198
To study the evolution of recombination rates in apes, we developed methodology to construct a fine-scale genetic map from high-throughput sequence data from 10 Western chimpanzees, Pan troglodytes verus. Compared to the human genetic map, broad-scale recombination rates tend to be conserved, but with exceptions, particularly in regions of chromosomal rearrangements and around the site of ancestral fusion in human chromosome 2. At fine scales, chimpanzee recombination is dominated by hotspots, which show no overlap with those of humans even though rates are similarly elevated around CpG islands and decreased within genes. The hotspot-specifying protein PRDM9 shows extensive variation among Western chimpanzees, and there is little evidence that any sequence motifs are enriched in hotspots. The contrasting locations of hotspots provide a natural experiment, which demonstrates the impact of recombination on base composition. 相似文献
305.
Zaman MA Iqbal Z Abbas RZ Khan MN Muhammad G Younus M Ahmed S 《Veterinary parasitology》2012,186(3-4):431-436
The anti-tick efficacy of combined aqueous herbal extracts of Azadirachta indica leaves, Nicotiana tabacum leaves, Calotropis procera flowers and Trachyspermum ammi seeds was evaluated using adult immersion test, larval packet test and ear bag method. The extract exhibited lethal effects on egg laying (index of egg laying=0.371404±0.00435), hatching (22.35%) and total larval mortality at 50 mg ml(-1) and reduced tick intensity on the infested calves (18 detached out of 35 at 45% (w/w) suspension, topically applied). The herbal extract exerted dose- and time-dependent response against all the developmental stages of Rhipicephalus (Boophilus) microplus considered in this study, thus justified their use in the traditional system of Pakistan. 相似文献
306.
Ghias Uddin Abdur Rauf Abdulaziz M. Al-Othman Simona Collina Muhammad Arfan Gowhar Ali Inamullah Khan 《Fitoterapia》2012
Pistacia integerrima Stewart in traditionally used as folk remedy for various pathological conditions including diabetes. In order to identify the bioactive compound responsible for its folk use in diabetes, a phytochemical and biological study was conducted. Pistagremic acid (PA) was isolated from the dried galls extract of P. integerrima. Strong α-glucosidase inhibitory potential of PA was predicted using its molecular docking simulations against yeast α-glucosidase as a therapeutic target. Significant experimental α-glucosidase inhibitory activity of PA confirmed the computational predictions. PA showed potent enzyme inhibitory activity both against yeast (IC50: 89.12 ± 0.12 μM) and rat intestinal (IC50: 62.47 ± 0.09 μM) α-glucosidases. Interestingly, acarbose was found to be more than 12 times more potent an inhibitor against mammalian (rat intestinal) enzyme (having IC50 value 62.47 ± 0.09 μM), as compared to the microbial (yeast) enzyme (with IC50 value 780.21 μM). Molecular binding mode was explored via molecular docking simulations, which revealed hydrogen bonding interactions between PA and important amino acid residues (Asp60, Arg69 and Asp 70 (3.11 Å)), surrounding the catalytic site of the α-glucosidase. These interactions could be mainly responsible for their role in potent inhibitory activity of PA. PA has a strong potential to be further investigated as a new lead compound for better management of diabetes. 相似文献
307.
Dundon WG Heidari A Fusaro A Monne I Beato MS Cattoli G Koch G Starick E Brown IH Aldous EW Briand FX Le Gall-Reculé G Jestin V Jørgensen PH Berg M Zohari S Metreveli G Munir M Ståhl K Albina E Hammoumi S Gil P de Almeida RS Smietanka K Domańska-Blicharz K Minta Z Van Borm S van den Berg T Martin AM Barbieri I Capua I;EPIZONE Network of Excellence Molecular Epidemiology of AI;APMV working group 《Veterinary microbiology》2012,154(3-4):209-221
Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented. 相似文献
308.
Hasan Muhammad Mehedi Ushio Hideki Ochiai Yoshihiro 《Fish physiology and biochemistry》2021,47(5):1477-1488
Fish Physiology and Biochemistry - Recombinant expression system was established for rainbow trout myoglobin (Mb) considering its unique primary structure of having one unusual deletion and two... 相似文献
309.
M. Ramzan M. Akhtar F. Muhammad I. Hussain E. Hiszczyńska-Sawicka A. U. Haq M. S. Mahmood M. A. Hafeez 《Tropical animal health and production》2009,41(7):1225-1229
Toxoplasmosis, an infection caused by Toxoplasma (T.) gondii Apicomplexa protozoan, is widespread in humans and other animal species, having already been reported in many countries and
different climates. In Pakistan, no data is available on this aspect among food animals. This study was undertaken to determine
the seroprevalence of T. gondii infection in sheep and goats. A total of 200 serum samples from sheep and goats, were collected from urban area of Rahim
Yar Khan (Punjab), Pakistan and tested for Toxoplasmosis with a commercial latex agglutination kit (Eiken Chemical Co., Ltd.
Japan). The overall seroprevalence of Toxoplasmosis was 19%. Goats had a significantly higher (p < 0.01) prevalence (25.4%)
as compared to the sheep (11.2%); and higher (p < 0.01) in the female (24%) than in the males (19%) for both species. In the
present study the male (both in sheep and goat) are found less seropositive T. gondii (OR = 0.23; 99% C.I. = 0.01, 1.81) as compared to female sheep and goat. The prevalence was significantly higher (p < 0.01)
in adult sheep than younger animals. Among both the sheep and goats the group from 1–1.5 years are highly seropositive (OR = 1.75;
99% C.I. = 0.47, 6.51) as compared to the group less than one year of age followed by the 2–2.5 years age group (OR = 1.63;
99% C.I. = 0.50, 5.74) whereas group with more than 3 years of age least seropositive. 相似文献
310.
Faqir Muhammad Masood Akhtar M. Irfan Anwar M. Javed Arshed 《Veterinary research communications》2009,33(8):971-977
Ciprofloxacin was administered intravenously @ 5 mg/kg body weight to six healthy dogs. After a washout period of two weeks,
fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for
ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 ± 0.32
vs. 1.79 ± 0.43 L/Kg, respectively. The elimination half life was 2.23 ± 0.78 and 2.07 ± 0.74 hours in healthy and febrile
dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 ± 0.06
and 0.60 ± 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant.
This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus,
the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters
in diseased animals. 相似文献