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101.
Plants have evolved different but interconnected strategies to defend themselves against microbial pathogens and stress conditions. The defense responses of tomato (Lycopersicon esculentum Mill) seedlings treated with dl ‐β‐aminobutyric acid (BABA) were investigated with and without abiotic stress (100 mM NaCl) against bacterial speck disease caused by Pseudomonas syringae pv. tomato. The plants were sprayed with 50, 125, 250 or 500 μg ml−1 BABA and were inoculated with 108 colony‐forming units ml−1 bacterial suspension 1 day after treatment. Abiotic stress led to an increase in plant resistance. When BABA was additionally applied as a foliar spray at 125 μg ml−1, the effect on plants was almost identical to that on plants that were sprayed with BABA at 500 μg ml−1 alone. The bacterial multiplication in the plants was 250‐fold lower than in the water‐treated (control) plants and in plants that were sprayed with 500 μg ml−1 BABA alone within 48 h postinoculation (hpi). Physiological studies were carried out in the plants treated with BABA in order to investigate the reason for this synergistic effect. Abiotic stress with BABA spray resulted in high H2O2 generation and guaiacol peroxidase activity in the plants. The activity of the enzymatic antioxidative protective system of the plants, superoxide dismutase, ascorbate peroxidase and catalase (CAT), also showed a significant delayed increase in BABA‐treated plants under abiotic stress conditions. These increases in enzyme activity coincided with the initiation of the most suppressive effect of BABA on bacterial growth by 24 hpi, which were significantly higher than the control. Salt stress alone did not lead to any significant increase in CAT activity, but salt stress with BABA did. These findings indicate a synergistic effect between salt stress and BABA at low concentrations, resulting in induced plant resistance. Furthermore, a stress regulation effect of BABA under abiotic stress can be associated with plant resistance.  相似文献   
102.
Aggrecanases are recently discovered enzymes that cleave aggrecan, a key component of cartilage. Aggrecanase inhibitors may provide a unique means to halt the progression of cartilage destruction in osteoarthritis. The synthesis and evaluation of biphenylsulfonamidocarboxylic acid inhibitors of aggrecanase-1 are reported. Compound 24 demonstrated 89% inhibition of proteoglycan degradation at 10 microg/mL and has an oral bioavailability in rat of 35%.  相似文献   
103.
Ig gene conversion is most likely initiated by activation-induced cytidine deaminase-mediated cytosine deamination. If the resulting uracils need to be further processed by uracil DNA glycosylase (UNG), UNG inactivation should block gene conversion and induce transition mutations. In this study, we report that this is indeed the phenotype in the B cell line DT40. Ig gene conversion is almost completely extinguished in the UNG-deficient mutant and large numbers of transition mutations at C/G bases accumulate within the rearranged Ig L chain gene (IgL). The mutation rate of UNG-deficient cells is about seven times higher than that of pseudo V gene-deleted (psiV-) cells in which mutations arise presumably after uracil excision. In addition, UNG-deficient cells show relatively more mutations upstream and downstream of the VJ segment. This suggests that hypermutating B cells process activation-induced cytidine deaminase-induced uracils with approximately one-seventh of uracils giving rise to mutations depending on their position.  相似文献   
104.
It is known that some of the enzymes and substances secreted by 2nd and 3rd stages of the Lucilia sericata larvae to have bacteriostatic and bactericidal effects. From this point of view, we investigated the anti-leishmanial effect of larval secretions of the L. sericata on the Leishmania tropica both in vitro and in vivo conditions. In vitro: It was observed that promastigotes of L. tropica had undergone lyzis within 1min in the larval secretions of L. sericata. However, larval secretion was ineffective on the promastigotes within Novy-MacNeal-Nicolle (NNN) cultures and RPMI 1640 medium. In vivo: Seven groups of male Balb/C mice (6 study groups and 1 control group), each composed of eight weeks old 10 mice were formed. L. tropica promastigotes were injected subcutaneosly to the soles of the SG mice' feet. In study groups, cutaneous lesions were developed Limoncu et al., 1997 in 2 (20%) and 1 (10%) of the SG-1 and SG-2, respectively after 15days. There were L. tropica in the smears prepared from the lesions and L. tropica was observed in the cultures. Cutaneous lesions were not developed in 8 (80%), 9 (90%) and 10 (100%) of the SG-I, SG-II and SG-III, respectively. There were no cutaneous lesions developed in the soles of the feet. There were no L. tropica in the smears prepared from the infected soles of the feet neither L. tropica was observed in the cultures. Larval secretions were given into the cutaneous lesions to the feet soles of the SG-IV, V and VI mice after 6months. No healing was observed in the cutaneos lesions of 4 (40%), 5 (50%) and 1 (10%) of SG-IV, SG-V and SG-VI, after 6months, respectively. There were L. tropica in the smears prepared from the lesions and L. tropica was observed in the cultures. On the other hand, the lesions of 6 (60%), 5 (50%) and 9 (90%) of SG-IV, SG-V and SG-VI were diminished in size and disappeared completely after 6months. There were L. tropica observed in the smears prepared from the infected soles of the feet and no growth was observed in the cultures. In the smears prepared from the cutaneous lesions developed in the soles of the feet of the control group mice, L. tropica was visualized and observed in the cultures. A statistical significant difference was observed between study groups and control group (p<0.001). In our study we demonstrated for the first time that the secretions of the 2nd and 3rd stages sterile and pure larvae of L. sericata had effects on promastigotes of L. tropica in in vitro and very effective on amastigote forms in in vivo conditions.  相似文献   
105.
Pseudomonas fluorescens strains Wayne1R and Wood1R have proven capacities to improve plant health. Here we report the draft genome sequences and automatic annotations of both strains. Genome comparisons reveal similarities with P. fluorescens strain Pf-5, reveal the novelty of Wood1R, and indicate some genes that may be related to biocontrol.  相似文献   
106.
Aspergillus sojae, which is used in the making of koji, a characteristic Japanese food, is a potential candidate for the production of polygalacturonase (PG) enzyme, which of a major industrial significance. In this study, fermentation data of an A. sojae system were modeled by multiple linear regression (MLR) and artificial neural network (ANN) approaches to estimate PG activity and biomass. Nutrient concentrations, agitation speed, inoculum ratio and final pH of the fermentation medium were used as the inputs of the system. In addition to nutrient conditions, the final pH of the fermentation medium was also shown to be an effective parameter in the estimation of biomass concentration. The ANN parameters, such as number of hidden neurons, epochs and learning rate, were determined using a statistical approach. In the determination of network architecture, a cross-validation technique was used to test the ANN models. Goodness-of-fit of the regression and ANN models was measured by the R 2 of cross-validated data and squared error of prediction. The PG activity and biomass were modeled with a 5-2-1 and 5-9-1 network topology, respectively. The models predicted enzyme activity with an R 2 of 0.84 and biomass with an R 2 value of 0.83, whereas the regression models predicted enzyme activity with an R 2 of 0.84 and biomass with an R 2 of 0.69.  相似文献   
107.
The activity of proteolytic enzymes is commonly measured using casein as a substrate. A modified caseinolysis assay was developed with natural dyes such as juglone, lawsone, berberine, and quercetin for Subtilisin carlsberg, protease type XVI, and trypsin, respectively. The pH dependence and incubation time were determined. K(m), V(max), and k(cat)/K(m) values were also determined for these enzymes. Lawsone was found to be a better substrate than the others.  相似文献   
108.
Amoebiasis is a common and life-threatening disease. The discrimination of the pathogenic Entamoeba histolytica from the non-pathogenic Entamoeba dispar could be done by advanced methods such as enzyme immunoassay (EIA) and PCR. The aim of this study was to investigate the prevalence of amoebiasis in Izmir province, and differentiate the Entamoeba species by PCR and EIA. Stool samples of 2,047 individuals were examined by direct microscopy, formalin ethyl acetate concentration, trichrome staining and culture, and those found to be positive for E. histolytica/dispar by any of these methods were further analyzed by PCR and EIA for species identification. Fifty-nine of 2,047 (2.9%) stool samples were found to be positive for E. histolytica/dispar with microscopy and/or culture. Among these positive samples, E. histolytica was detected in 14 (23.7%) and 5 (8.5%) samples with PCR and antigen-specific ELISA (EIA), respectively. E. dispar was diagnosed in 31 (52.5%) and 52 (88.1%) of 59 samples with species-specific PCR and EIA, respectively. Risk factors related to infection with Entamoeba spp. and other intestinal parasites included living in shanty houses (p < 0.01), a history of recent immigration to Izmir (p < 0.01), having no social security (p < 0.05) and living with a crowded family (p < 0.01). The results demonstrated the significance of amoebiasis as a public health problem among people with low socio-economic status in Izmir province.  相似文献   
109.
The aim of the study was to investigate the arterial anatomy of the lower lip. The location, course, length, and diameter of the inferior labial artery and the sublabial artery were revealed by bilateral meticulous anatomic dissections in 14 adult male preserved cadaver heads. Another cadaver head was used for silicone rubber injection to fill the regional arterial tree. The inferior labial artery was the main artery of the lower lip and in all cases branched off the facial artery. The mean length of the inferior labial artery was found to be 52.3 mm (range, 16 to 98 mm). The mean distance of the origin of the inferior labial artery from the labial commissura was 23.9 mm. The mean external diameter of the inferior labial artery at the origin was 1.2 mm. The sublabial artery was present in 10 (71 percent) of the cadavers. Mean measurements of this artery were 1 mm for diameter, 23.4 mm for length, and 27.6 mm for distance from the labial commissura. The sublabial artery may originate from the facial artery or the inferior labial artery. This study found that this region does not have a constant arterial distribution, the inferior labial artery and the sublabial artery (if it exists) can be in different locations unilaterally or bilaterally, and the diameter and the length may vary.  相似文献   
110.
Spawn running, pin head and fruit body formation, and mushroom yield of oyster mushroom (Pleurotus ostreatus) on waste paper supplemented with peat, chicken manure and husk rice (90+10; 80+20 w:w) were studied. The fastest spawn running (mycelia development) (15.8 days), pin head formation (21.4 days) and fruit body formation (25.6 days), and the highest yield (350.2 gr) were realized with the substrate composed of 20% rice husk in weight. In general, increasing the ratio of rice husk within the substrate accelerated spawn running, pin head and fruit body formation, and resulted in increased mushroom yields, while more peat and chicken manure had a negative effect on growing.  相似文献   
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