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11.
Six isolates of Mycoplasma bovoculi obtained from cattle herds with bovine keratoconjunctivitis were analyzed by gel electrophoresis and immunoblotting techniques. All six strains showed similarity in their protein profiles although no two patterns were identical. Antigenic differences between strains were detected in immunoblots reacted with post-exposure calf serum. A common 94 kDa protein band designated p94 was detected in all six strains reacted with monoclonal antibody MA25.5 developed to one of the strains. The p94 was also recognized in these strains by the calf serum. Trypsin treatment of intact mycoplasma cells resulted in the removal of p94 from immunoblots reacted with MA or hyperimmune rabbit serum. Other trypsin-resistant antigens shared between strains or being strain-specific in nature were identified when trypsin-treated mycoplasma cells were reacted with hyperimmune rabbit serum. The p94 antigen was shown to be of mycoplasmal origin by radio-immunoprecipitation using the MA or hyperimmune rabbit serum. These studies identify the presence of a surface antigen (p94) on M. bovoculi membrane in all strains examined that is trypsin sensitive by the use of monoclonal antibody, calf serum and hyperimmune rabbit serum.

Résumé

Six souches de Mycoplasma bovoculi, d'origine bovine (animaux affectés de keratoconjunctivite) ont été analysées par des techniques d'éléctrophorèse et par ‘immunoblotting’. Les six souches ont montré des similitudes dans leurs profils proteiniques. Cependant, aucun profil n'a été identique. Des differences antigéniques entre les souches ont étés detectées suite au traitement des immunoblots avec un sérum bovin infecté par M. bovoculi. L'anticorps monoclonal MA25.5 dirigé contre une des souches a réagi avec une bande proteinique (94 kDa) commune aux six souches. Cette bande a été designee p94. Cette bande p94 a été également identifiée chez tous les souches en utilisant le sérum bovin. Le traitement des mycoplasmes intactes par la trypsine a éliminé la bande p94 des immunoblots: cela a été démontr é par l'usage d'un anticorps monoclonal, ou par un sérum hyperimmun de lapin. D'autres antigènes résistants à la trypsine, communs ou spécifiques aux souches ont été identifiés quand les mycoplasmes traités par le trypsine ont été mélangés au sérum hyperimmun de lapin. La radioimmunoprécipitation par l'anticorps monoclonal ou le sérum hyperimmun de lapin a demontré que l'antigène p94 est d'origine mycoplasmique. Ces études identifient la présence d'un antigène de surface (le p94) localisé sur la membranc de M. bovoculi chez toutes les souches examinées. Cet antigène est sensible à la trypsine. Cela a été montré avec l'anticorps monoclonal, le sérum bovin et le sérum hyperimmune du lapin.  相似文献   

12.
Verticillium dahliae isolates recovered from a new focus of severe Verticillium wilt of cotton in the northeast of Israel were tested for vegetative compatibility using nitrate non-utilizing (nit) mutants and identified as VCG1, which is a new record in Israel. Other cotton isolates of V. dahliae from the northern and southern parts of the country were assigned to VCG2B and VCG4B, respectively. VCG1 isolates induced severe leaf symptoms, stunting and defoliation of cotton cv. Acala SJ-2, and thus were characterized as the cotton-defoliating (D) pathotype, whereas isolates of VCG2B and VCG4B were confirmed as the earlier described defoliating-like (DL) and non-defoliating (ND) pathotypes, respectively. This is the first record of the D-pathotype in Israel. The host range of representative isolates of each VCG-associated pathotype was investigated using a number of cultivated plants. Overall, the D isolates were more virulent than DL isolates on all tested host plants, but the order of hosts (from highly susceptible to resistant) was the same: okra (Hibiscus esculentus local cultivar), cotton (Gossypium hirsutum cv. Acala SJ2), watermelon (Citrullus lanatus cv. Crimson Sweet), safflower (Carthamus tinctorius cv. PI 251264), sunflower (Helianthus annuum cv. 2053), eggplant (Solanum melongena cv. Black Beauty), and tomato (Lycopersicon esculentum cv. Rehovot 13). The pattern of virulence of ND isolates differed from that of D and DL isolates, so that the former were highly virulent on eggplant but mildly virulent on cotton. Tomato was resistant to all cotton V. dahliae isolates tested. RAPD and specific PCR assays confirmed that the D isolates from Israel were similar to those originating from other countries.  相似文献   
13.
Neurotoxicity complicates the use of several commonly administered chemotherapeutic agents (platinum based alkylating agents, taxanes and vinca alkaloids), with chemotherapy-induced peripheral neuropathy being the most common manifestation. Structural damage to the peripheral nervous system results in positive symptoms, e.g., allodynia, hyperalgesia and pain with unpleasant features as burning and shooting. Patients are unable to complete full or optimal treatment schedules. The pathophysiologic basis of nerve injury in chemotherapy-induced peripheral neuropathy is incompletely understood and appears to be unique for each class of the chemotherapeutic agents. Erythropoeitin (EPO), a well-established hematopoietic factor, is a very effective and widely used treatment for anemia in cancer patients undergoing chemotherapy. It also possesses generalized neuroprotective and neurotrophic properties. Co-treatment of chemotherapy and erythropoietin has been proposed for preventing or reversing the disabling peripheral neuropathy induced by the different chemotherapeutic agents. This study first describes the pathophysiological background of the clinically relevant chemotherapeutic agents-inducing peripheral neuropathy. Secondly, the possible mechanisms that might underlie the neuroprotective effect of erythropoietin in chemotherapy-induced neuropathy. Further clinical trials of EPO in cancer patients receiving chemotherapy and suffering from neurological symptoms seem to be warranted in the future. This might improve the quality of life in cancer patients.  相似文献   
14.
Vegetative compatibility (vc) and mating types and genetic diversity of Cryphonectria parasitica isolates were determined using 183 isolates obtained from 215 infected chestnut trees growing in 13 provinces of Turkey. Based on the cultural aspects, 143 of these isolates were evaluated as virulent whereas the remaining 40 isolates were hypovirulent. When vc types of 183 isolates were classically differentiated, 135 of them matched to EU-1 (82.3%), 29 of them to EU-12 (17.6%) vc type, whereas 19 of them did not match to the two. When molecular vic markers were used, all the isolates were assigned to two EU vc types; 149 to EU-1 (81.4%) and 34 (18.5%) to EU-12. Of the majority of the isolates, 134 (73.2%) had mating-type MAT-1, while 44 (24%) isolates had MAT-2 and 5 (2.8%) isolates had both mating types. The population analysis based on two DNA marker systems, Inter-Primer Binding Site and Start Codon Targeted Polymorphism, showed no intraspecific genetic variation among the C. parasitica isolates. The prevalence of two dominant vc types revealed by this study shows that biological control with hypovirulent EU-1 and EU-12 isolates will be significant for the country. The results might be helpful to chestnut breeders carrying out resistance breeding studies to manage this disease based on hypovirulence attributed to Cryphonectria hypovirus 1.  相似文献   
15.
The antifeedant effect of five organotin compounds (fentin acetate, fentin hydroxide, fentin chloride, cyhexatin and fenbutatin oxide) and of three other compounds known to possess antifeeding activity (guazatine triacetate, 4′-chloroacetophenone isobutyrylhydrazone and thiram) was investigated by feeding treated alfalfa to larvae of Boarmia selenaria. The three fentins and cyhexatin were highly active at 0.1 g litre?1, the order of activity at this concentration being fentin chloride > fentin hydroxide > fentin acetate ? cyhexatin, whereas the other compounds were practically inactive at either this or a somewhat higher concentration (0.5 g litre?1). Guazatine triacetate had a concentration-independent antifeedant effect at much higher concentrations (5–20 g litre?1).  相似文献   
16.
Solid olive residues (SOR) are byproducts of the olive-milling process, but they have an increasing importance in the pharmaceutical industry due to their rich content of biophenols. Such compounds are studied widely for their antioxidant and antimicrobial activities, but there is a lack of information about their quantitative recovery. This research highlighted the key role played both by the selection of the cultivar and by the degree of olive fruit ripening on the phenolic content on the SOR. The extraction methods were selected to reach the best quantitative results mainly using a safe food solvent. In light of the results the Soxhlet extraction with ethanol could be proposed as preferential for a higher recovery of verbascoside and its analogues.  相似文献   
17.
Enzymatic synthesis of aroma compound xylosides was performed by Trichoderma longibrachiatum xylanase. Information concerning the nature of xylosides present in the reaction medium was obtained by GC-EI-MS, by GC-NCI-MS of TFA derivatives, and by positive FAB-MS of the reaction mixtures. Moreover, the structures of isolated benzyl beta-D-xylopyranoside and 4-O-beta-xylopyranosyl-beta-D-xylopyranoside were established by (1)H and (13)C NMR and heteronuclear two-dimensional ((1)H-(13)C) chemical shift correlation. The results obtained for hexyl and benzyl alcohol xylosides indicated that a reaction implying a transfer of one to two or three xylose units from xylan was involved. The enzyme was able to recognize xylobiose, xylotriose, and xylan as xylose donors. Benzyl xyloside, produced independently of xylobioside and xylotrioside, was found as the major kinetic product of the reaction. Benzyl xyloside was produced in higher quantities and at a higher rate than that obtained for the di- and trixyloside derivatives. The maximum production for benzyl xyloside, 1.29 g/L, was obtained in the presence of hexane (50%) used as cosolvent. Xylosides and xylobiosides of several aroma compounds, (Z)-hex-3-en-1-ol, heptan-2-ol, geraniol, nerol, and citronellol, were synthesized in different amounts, from 850 mg/L for (Z)-hex-3-en-1-yl xylosides to 1.5 mg/L for citronellyl xylosides. No synthesis occurred when menthol, linalool, and eugenol were used as acceptors.  相似文献   
18.
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing.  相似文献   
19.
Methyl jasmonate, jasmonic acid and chitosan were tested as elicitors on cell suspension cultures obtained from Vitis vinifera cv Italia to investigate their effect on stilbene production. Stilbene accumulation in the callus, grown under nonelicited conditions, was also investigated. Calli and cell suspensions were obtained in a B5 culture medium supplemented with 0.2 mg L(-1) NAA and 1 mg L(-1) KIN. Stilbene determination was achieved by HPLC/DAD/MS. Whereas callus biosynthesized only piceid, cell suspensions elicited with jasmonates produced several stilbenes, mainly viniferins. In suspended cells, methyl jasmonate and jasmonic acid were the most effective in stimulating stilbene biosynthesis, whereas chitosan was less effective; in fact, the amount of stilbenes obtained with this elicitor was not significantly different from that obtained for the control cells. The maximum production of total stilbenes was at day 20 of culture with 0.970 and 1.023 mg g(-1) DW for MeJA and JA, respectively.  相似文献   
20.
The effect of Baghdad city on the water quality of the Tigris River was studied from April 1977 to March 1978. The chemical and physical characteristics of the water which are necessary in judging the quality of water for irrigation were studied. It was found that Baghdad was responsible for increasing the water salinity from 390 to 443 mg l?1. Total hardness and turbidity were increased when the river passed through Baghdad. The increase in the total hardness was mostly due to the increase in Mg concentration. The results also suggested that there should be no problem from the heavy metals or inorganic N in this water when used for irrigation. The Tigris River water in Baghdad was classified as classC 2 S 1; that is water of second class with regard to salinity and first class with regard to sodicity.  相似文献   
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