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1.
Kim M. Plummer Sarah J. Clark Lana M. Ellis Ashwini Loganathan Taha H. Al-Samarrai Erik H.A. Rikkerink Patrick A. Sullivan Matthew D. Templeton Peter C. Farley 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(3):265-274
Peptidases have been implicated in the pathogenicity of fungi that cause disease in plants. Expression of the secreted aspartic peptidase gene (gcsap), of a Glomerella cingulata isolate pathogenic on apples, is induced during appressorium formation. To determine whether the secreted aspartic peptidase (GcSAP) is essential to pathogenicity, gcsap was disrupted using a vector containing a 637 bp fragment of genomic DNA that encodes the sequence spanning the two active site aspartic acid (Asp) residues. To ensure that the truncated gcsap gene products could not have residual peptidase activity the codons for the active site residues Asp112 and Asp297 were both mutated to histidine residues. Both PCR and Southern analysis confirmed disruption of gcsap. Neither gcsap mRNA nor GcSAP activity was detected in the disruption mutant. Pathogenicity tests on fruit from three apple cultivars showed that GcSAP was not required for pathogenicity. The disruption mutant grew on medium containing protein as the sole source of nitrogen because G. cingulata secretes a previously undetected peptidase(s). A serine peptidase that had a pH optimum between pH 7.0 and 8.0 and a K
m of 0.25 mM for the synthetic substrate succinyl-Ala–Ala–Pro–Phe-p-nitroanilide was identified. 相似文献
2.
Ahmed M Kimura K Soliman M Yamaji D Okamatsu-Ogura Y Makondo K Inanami O Saito M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(2):125-131
Leptin, a pleiotropic hormone regulating food intake and energy expenditure, has been shown to directly modulate human polymorphonuclear neutrophil (PMN) functions or indirectly through the action of tumor necrosis factor-alpha (TNF-alpha). Bovine PMN have considerable different characteristics from human PMN. For example, it does not respond to N-formyl-Methionyl-Leucyl-phenylalanine, a well known human PMN activator. In the present study, we tested the effects of leptin and TNF-alpha on superoxide production and degranulation of bovine peripheral PMN, in which both long isoform of leptin receptor (Ob-Rb) and TNF receptor 1 were expressed. Human leptin, human TNF-alpha, phorbol myristate acetate (PMA) and opsonized zymosan particles (OZP) did not stimulate degranulation responses, while zymosan-activated serum (ZAS) did. Neither leptin nor TNF-alpha enhanced the ZAS-induced degranulation responses. TNF-alpha, PMA, OZP and ZAS increased superoxide production in different magnitudes, whereas leptin did not. TNF-alpha, but not leptin, enhanced OZP- and ZAS-induced superoxide production, possibly, in part due to facilitating translocation of p47(phox), a component of NADPH oxidase. These results indicate that, unlike in human PMN, leptin does not have any direct effect on degranulation and superoxide production in bovine PMN, although TNF-alpha influences superoxide production. 相似文献
3.
The main objective of the study was to evaluate the sensitivity of Iraqi local barley cultivar (Black) to soil water deficit as compared to other barley cultivars, namely: CM-72 and Arivat. The local cultivar proved to be susceptible during germination and emergence, but it developed resistance during the vegetative growth and yield formation stages. Growth analysis of individual leaves clearly showed that Black barley produced leaves of long growth duration which could affect the growth processes especially cell division. Thus, the reduction in the number of cells composing those leaves was small in the cultivar Black. Leaf growth rates as soil matric potential decreased, were reduced considerably, although, no clear trends were observed between cultivars. On the other hand, the smaller cell volume of local cultivar may have a role in its ability to tolerate water deficit. Some evidence that the local cultivar is post-flowering resistant is discussed. 相似文献
4.
Mahmoud A.O. Dawood Mahmoud S. Gewaily Ali A. Soliman Mustafa Shukry Asem A. Amer Elsayed M. Younis Abdel-Wahab A. Abdel-Warith Hien Van Doan Adel H. Saad Mohamed Aboubakr Hany M.R. Abdel-Latif Sabreen E. Fadl 《Marine drugs》2020,18(12)
Marine-derived substances are known for their beneficial influences on aquatic animals’ performances and are recommended to improve intestinal health, immunity, and anti-oxidative status. The present study investigates the role of chitosan nanoparticles on the intestinal histo-morphometrical features in association with the health and immune response of Grey Mullet (Liza ramada). Chitosan nanoparticles are included in the diets at 0, 0.5, 1, and 2 g/kg and introduced to fish in a successive feeding trial for eight weeks. The final body weight (FBW), weight gain (WG), and specific growth rate (SGR) parameters are significantly increased while feed conversion ratio (FCR) decreases by chitosan nanoparticles compared to the control (p < 0.05). The morphometric analysis of the intestines reveals a significant improvement in villus height, villus width, and the number of goblet cells in chitosan-treated groups in a dose-dependent manner. Additionally, there is a positive correlation between the thickness of the enterocyte brush border and the chitosan dose, referring to an increasing absorptive activity. Histologically, the intestinal wall of Grey Mullet consists of four layers; mucosa, sub-mucosa, tunica muscularis (muscular layers), and serosa. The histological examination of the L. ramada intestine shows a normal histo-morphology. The epithelial layer of intestinal mucosa is thrown into elongated finger-like projections, the intestinal villi. The values of hemoglobin, hematocrit, red blood cells (RBCs), total protein (TP), albumin, and globulin are significantly increased in fish fed 1, and 2 g/kg of chitosan nanoparticles compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest levels of TP and albumin are observed in fish fed 1 g/kg diet (p < 0.05). The lysozyme activity and phagocytic index are significantly enhanced by feeding chitosan nanoparticles at 0.5, 1, and 2 g/kg, whereas the phagocytic activity is improved in fish fed 1 and 2 g/kg (p < 0.05). The highest lysozyme activity and phagocytic index are observed in fish fed 1 g/kg. SOD is significantly activated by feeding chitosan nanoparticles at 1 g/kg. Simultaneously, glutathione peroxidase (GPx) and catalase (CAT) activities also are enhanced by feeding chitosan at 1 and 2 g/kg, compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest GPx and CAT activities are observed in fish fed 1 g/kg (p < 0.05). Conversely, the malondialdehyde (MDA) levels are decreased by feeding chitosan at 1 and 2 g/kg, with the lowest being in fish fed 1 g/kg (p < 0.05). To summarize, the results elucidate that L. ramada fed dietary chitosan nanoparticles have a marked growth rate, immune response, and anti-oxidative response. These improvements are attributed to the potential role of chitosan nanoparticles in enhancing intestinal histo-morphometry and intestinal health. These results soundly support the possibility of using chitosan nanoparticles at 1–2 g/kg as a feasible functional supplement for aquatic animals. 相似文献
5.
Elsheikh HA Taha AA Khalafalla AE Osman IA Wasfi IA 《Veterinary research communications》1999,23(8):507-514
The pharmacokinetics of amoxicillin were studied in five Desert sheep and five Nubian goats after intravenous (i.v.) or intramuscular (i.m.) administration of a single dose of 10 mg/kg body weight. Following i.v. injection, the plasma concentration-versus-time data were best described by a two-compartment open model. The kinetic variables were similar in both species except for the volume of the central compartment (Vc), which was larger in sheep (p<0.05). Following i.m. injection, except for the longer half-life time of absorption in goats (p<0.05), there were no significant differences in other pharmacokinetic parameters between sheep and goats. The route of amoxicillin administration had no significant effect on the terminal elimination half-life in either species. The bioavailability of the drug (F) after i.m. administration was high (>0.90) in both species. These results indicate that the pharmacokinetics of amoxicillin did not differ between sheep and goats; furthermore, because of the high availability and short half-life of absorption, the i.m. route gives similar results to the i.v. route. Therefore, identical intramuscular and intravenous dose regimens should be applicable to both species. 相似文献
6.
Ishioka K Soliman MM Sagawa M Nakadomo F Shibata H Honjoh T Hashimoto A Kitamura H Kimura K Saito M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(4):349-353
Leptin is a protein synthesized and secreted primarily by adipocytes, and the circulating leptin concentration is elevated in obese humans and rodents. Recently, we have established a sandwich enzyme-linked immunosorbent assay for canine leptin. In the present study, plasma leptin concentrations were measured in experimentally developed obese beagles and in clinically obese dogs. When 5 male beagles were given a high-energy diet for 3 months, all of them became obese and the plasma leptin concentration significantly increased from 2.4+/-1.2 to 4.9+/-0.9 ng/ml, positively correlating with body fat content estimated by the deuterium oxide dilution method (r=0.87). The leptin concentrations of plasma samples collected from 59 dogs in veterinary practices were compared with their body condition scores (BCS). The plasma leptin concentrations of obese dogs were 9.7+/-0.7 and 12.3+/-1.5 ng/ml at BCS=4 and BCS=5, respectively, which were significantly higher than those of optimal (BCS=3) dogs (2.7+/-0.3 ng/ml). There was no significant effect of sex and breed. A weak positive correlation (r=0.37) was found between the plasma leptin concentration and age, probably due to the lesser content of visceral fat in puppies younger than 1 year old. These results indicate that plasma leptin is a good index of adiposity in dogs regardless of breed, age and sex, and may be useful for quantitative assessment of obesity in small animal practice. 相似文献
7.
The pharmacokinetics of kitasamycin after intravenous and oral administration in a dose of 300 mg/kg b.wt. was studied in 18 healthy and 18 Salmonella gallinarum naturally infected chickens. The tissue residue of the studied antibiotic was estimated in 36 normal chickens when it was given orally for 7 successive days. Therapeutic level of kitasamycin was achieved after 15 minutes and persisted for 20-22 hours after its oral administration. Higher serum kitasamycin concentrations were recorded in Salmonella gallinarum infected chickens. The elimination half-life of kitasamycin calculated after single intravenous injection was 9.03 hours in diseased chickens corresponding to 3.74 hours in healthy birds. The body clearance was significantly reduced in diseased chickens (23.86 ml/kg/min) when compared to that in normal ones (62.03 ml/kg/min). Kitasamycin treated broilers should not be slaughtered before 3 days from the last dose as it was detected only in bile and caecum at that time but not in edible tissues. 相似文献
8.
M M Hassanain A I al-Afaleq I M Soliman S K Abdullah 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1990,43(1):33-35
Two 7-year old Arabian racing horses were reported to show typical AHS symptoms in Qatar and died shortly after. The horses had been vaccinated with formol inactivated vaccine approximately 10 days before the onset of the disease. Blood samples from these horses were collected and AHS virus isolated from one sample after intracerebral (i.c.) inoculation into suckling mice. The virus identity was confirmed by complement fixation test (CFT) using the virus antigen and reference type 9 of AHS virus hyperimmune serum. The serotype of the isolated virus was identified by serum neutralization test (SNT) using reference types of AHS virus. Two possibilities of the original source of this infection were suggested. The infection might be due first to the natural endemic occurrence of the virus in the country and secondly, to the presence of residual infectious virus in the inactivated vaccine. 相似文献
9.
Studies on the biology of the predaceous mite Cunaxa capreolus Berl. (Acari, Prostigmata, Cunaxidae) During life cycleCunaxa capreolus Berlese passes through egg, larva, three nymphal stages and adult. Each moving stage is proceeded by a quiescent one. Biological process such as hatching, moulting and mating were investigated. Female usually deposites its eggs singly in protected places. Number of deposited eggs per female, when fed on book lice (Psocoptera), was positively correlated with temperature. It averaged 24.6, 30.7, 40.7, and 43.5 eggs at 15°, 20°, 25° and 30 °C. Incubation period as well as duration of immature stages and adult longevity were negatively effected with temperature. The generation period (from egg to egg) ranged from 24.8 to 64.2 days when temperature changed from 30° to 15 °C. Within these limits of temperature, the simple regression indicated that an increase of 1 °C decreased the generation period for about 2.6 days. 相似文献
10.
Ahmed NE Farag MM Soliman KM Abdel-Samed AK Naguib KhM 《Journal of agricultural and food chemistry》2007,55(23):9576-9580
A comparative study was conducted to evaluate four previously reported methods that proved to have a recovery greater than 80% for the determination of different levels of ochratoxin A (OTA) in green and roasted coffee beans and to select an accurate, sensitive, and less-expensive technique between the existing methods. The results indicated that the Association of Official Analytical Chemists (AOAC) official method for the extraction of OTA in green coffee and determination by high-performance liquid chromatography (HPLC) is recommended as an efficient method for the routine analyses of OTA in green and ground roasted coffee beans. This method proved to be an accurate, sensitive, and less-expensive method that employs routine materials and available equipment. Although the immunoaffinity column/HPLC procedure tested showed a significantly higher percentage than the AOAC recommended method, it is recommended for use in processed coffee beans where low concentrations of OTA may be expected to be detected. 相似文献