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Julio Avila Elisa Acosta María-del-Valle Machargo María-Francisca Arteaga Eduardo Gallego Haridian Cañete José-Javier García-Pérez Pablo Martín-Vasallo 《Journal of Autoimmune Diseases》2008,5(1):3
Background
Systemic vasculitides constitute a heterogeneous group of diseases of autoimmunological origin characterized by inflammation of blood vessels and antibodies that react against autoantigens in a process that ultimately affects blood vessel walls. An important number of these patients present kidney disease. An endeavour of this area of research is the identification of autoantigens involved in these diseases. Accordingly, we used serum from a patient suffering from a microscopic polyangiitis, P-ANCA positive, manifesting a clinically atypical renal necrotizing glomerulonephritis and interstitial nephropathy for the identification of autoantigens; we also determined the prevalence of corresponding autoantibodies in other vasculitides, diabetic microangiopathy and in general population.Methods
The patient's serum was used as a probe for the immunoscreening method SEREX to screen a human brain cDNA expression library.Results
Four positive clones were isolated and sequenced. Clones Jos002 code for protein HDAC5, Jos014 for TFC4, Jos107 for RTF1, and Jos313 for POLDIP3 polymerase. The four proteins are of nuclear localization. None of them had been reported as autoantigen. Recombinant proteins were synthesised and checked as antigens by western blot with different sera from controls and patients affected with other vasculitides and diabetic microangiopathy as well. Only the serum from the patient origin of this study recognized all recombinant proteins.Conclusion
We identify four nuclear proteins, HDAC5, TFC4, RTF1 and POLDIP3 polymerase as new autoantigens that could be used as markers in the diagnosis of subfamilies in immune diseases, although we cannot determine the role of these proteins in the aetiopathogenic process.54.
Adrian Ponce de León Door Alejandro Romo Chacón Carlos Acosta Muñiz. 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(2):223-229
Fire blight, one of the most severe diseases of apple and pear, is caused by the bacterium Erwinia amylovora. One control method is the use of antibiotics like streptomycin; however, streptomycin is the only antibiotic registered to control fire blight. A total of 107 E. amylovora strains were isolated from apple orchards located in Cuauhtémoc and Guerrero, Chihuahua, two major apple-producing areas in Mexico, showing 40 and 24 % streptomycin-resistant strains, respectively. The identification of E. amylovora strains was performed by polymerase chain reaction (PCR) amplification of a 900-bp region located within the non-transferable pEA29 plasmid and by amplification of a specific 1,269-bp region located on the E. amylovora chromosome. The 107 isolates tested carried the pEA29 plasmid, and 36 % of the isolates from both locations showed high resistance to streptomycin at levels that ranged from 200 to ≥1,000 μg ml?1 streptomycin. The strA-strB and aadA genes, which encode enzymes that inactivate streptomycin, and a mutation in codon 43 of the rpsL gene that confers high resistance to the antibiotic were examined to determine the mechanism of streptomycin resistance. In total, 95 % of the resistant strains showed a single base pair mutation in codon 43 of the rpsL gene, causing an amino acid substitution in ribosomal protein S12. The presence of strA-strB and aadA genes or the rpsL mutation was not identified in the other 5 % of resistant strains, suggesting the existence of a new streptomycin resistance mechanism in E. amylovora. 相似文献
55.
Vela Acosta MS Sanderson M Cooper SP Pérez A Roberts RE 《Journal of agricultural safety and health》2007,13(2):117-136
Adolescents may engage in health risk behaviors that increase their likelihood of injury. Employment places adolescents at risk of work-related injuries. This study responds to the paucity of data on the relationship between adolescent health risk behaviors and work-related injury. This cross-sectional study included the administration of anonymous surveys to ninth graders (n=4914) who attended high schools in south Texas. An aggregate risk score (ARS) was developed based on health risk behaviors. The ARS was analyzed as an outcome using linear regression. Associations between health risk behaviors and work-related injury were assessed with logistic regression. Of the respondents, 19% reported they had a job, and 14% reported that they had been employed in farmwork. Farmwork-related injury was reported by 9% of adolescents, and 12% reported other work-related injury. Mean ARS scores were significantly higher (p < 0.05) for both male and female adolescents who reported a work-related injury compared to nonworking adolescents, and for males who had done migrant farmwork compared to all other adolescent males. The ARS increased as hours worked per week increased. After controlling for confounding factors, a statistically significant association was found between ARS and non-farmwork, work-related injury, but not between ARS and farmwork-related injury. Farmworkers with high ARS were more likely to report non-farmwork, work-related injuries. The predictors of work-related injury in the adolescent groups, particularly for farmworkers and migrants who are under additional stress, remain an important occupational health area to be addressed. 相似文献
56.
Enzyme activities in semiarid soils under conservation reserve program,native rangeland,and cropland
There is limited knowledge of biochemical processes in low carbon content soils of semiarid regions under different land use and management. This study investigated several enzyme activities of C, N, P, and S transformations in semiarid soils with different clay (10–21 %) and sand (59–85 %) contents that were under conservation reserve program (CRP), native rangeland (NR), and cropland (CL) under sunflowers (Eriophyllum ambiguum (Gray)), continuous cotton (Gossypium hirsutum L.), or in rotations with wheat (Triticum aestivum L.) or sorghum (Sorghum bicolor L.) in West Texas, USA. Soils under CRP and NR showed higher total C and N contents than cultivated soils under continuous cotton, but soil pH (6.7–8.4) was not affected by the management or land use studied. The activities of β‐glucosidase, β‐glucosaminidase, arylamidase, acid and alkaline phosphatase, phosphodiesterase, and arylsulfatase (mg product (kg soil)–1 h–1) were lower in CL under continuous cotton compared to cotton in rotation with other crops, CRP, and NR. The enzyme activities were also lower when compared to soils from other regions. Linear regression analyses indicated positive correlations between enzyme activities and total C (r values up to 0.96, P < 0.01). There was a positive relationship between enzyme activities and total N, but soil pH showed the opposite trend. Enzyme activities were significantly intercorrelated with r values up to 0.98 (P < 0.001). The specific enzyme activities (mg product (g organic C)–1) were lower in continuous cotton in comparison to the uncultivated soils (i.e., NR and CRP) reflecting differences in organic matter quantity and quality due to cultivation. Among the enzymes studied, the specific activities of β‐glucosidase and arylamidase showed a more pronounced decrease with increasing soil depth. In general, soils under CRP or wheat‐cotton rotations revealed higher enzyme activities than soils under the common agricultural practice for these regions, i.e., continuous cotton under conventional tillage. 相似文献
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Padilla D Real F Gómez V Sierra E Acosta B Déniz S Acosta F 《Journal of fish diseases》2005,28(7):411-417
Virulence factors (eae gene, haemolytic capacity, fimbriae, resistance to the bactericidal effect of serum, siderophore production) and pathogenicity for gilthead seabream, Sparus aurata L., were analysed for 23 Hafnia alvei strains. None of the strains used in LD50 studies were lethal for seabream at doses as high as >10(8) cfu mL(-1). In chronic challenge studies differences in severity of the inflammatory response were observed between strains. On the basis of correlation of the inflammatory response to different strains of H. alvei in seabream with those virulence factors studied, it was only possible to establish a positive correlation between pathogenicity and resistance to the bactericidal effect of fish serum. Gilthead seabream is thus a species with considerable resistance to experimental infection with H. alvei. The bacterium does, however, have the capacity to remain viable in seabream for up to 3 months, without any clinical signs. Hafnia alvei is a well-recognized human and animal pathogen. Thus, as the pathogen can coexist with aquaculture operations, cultured gilthead seabream could represent a risk to human health as a carrier in some circumstances. 相似文献
59.
da Silva Acosta D Kneip FC Alves de Almeida E Ventura-Lima J Monserrat JM Geracitano LA 《Fish physiology and biochemistry》2012,38(5):1477-1485
The carbon nanomaterial fullerene (C(60)) can act as anti or pro-oxidant. The aim of this study was to evaluate, in cell suspensions of carp brains (Cyprinus carpio, Cyprinidae), the effect of C(60) after a pre-treatment with polyunsaturated fatty acid (PUFAs) such as omega-3 (docosahexaenoic acid, DHA) and omega-6 (linoleic acid, LA). Assays consisted of a pre-treatment with PUFA (48?h) and then exposure to C(60) (2?h). Cell viability and total anti-oxidant capacity did not differ (p?>?0.05). A reduction (p?0.05) was observed in reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) concentration in fish brain cells pre-exposed with PUFA groups and then exposed or not with C(60). An antioxidant effect of C(60) was evident since in control group (cells not pre-exposed to PUFA), a significant (p?0.05) reduction of intracellular ROS concentration was observed, although this reduction was not enough to reduce the TBARS levels. Cysteine levels presented a reduction (p?0.05) in all groups exposed to C(60). For glutathione (GSH), an increase (p?0.05) was registered in cells exposed to C(60) without PUFAs pre-treatment and in the C(60) group pre-treated with DHA. Overall C(60) appears to play an antioxidant role that is modulated by PUFA, taking into account its effects on intracellular ROS concentration and MDA levels. Results also suggest that C(60) influences GSH synthesis, as showed for the augmented levels of this antioxidant and also for the lowering of the intracellular cysteine concentration. 相似文献
60.
J M Acosta D J Bentivegna E S Panigo I Dellaferrera M Alisio M G Perreta 《Weed Research》2014,54(6):584-592
Iresine diffusa has become more abundant under no‐till soyabean in Argentina. The influence of temperature, light, cold‐wet storage, osmotic potential, dry storage and depth of seed burial on germination and emergence of I. diffusa was examined in a growth chamber experiment. Iresine diffusa seeds germinated at the highest proportion (>0.80) in all fluctuating day/night temperatures tested. Conversely, under a constant temperature regime, maximum germination rates occurred at 15 (0.78) and 20°C (0.82), and minimum germination rates occurred at 10 (0.19) and 30°C (0.36). Seed germination was not influenced by light exposure. However, germination decreased after 12 (0.76) and 16 (0.65) weeks in cold‐wet storage. To reduce germination significantly, ?0.4 MPa of osmotic potential (induced by PEG‐6000) or 120 mmol L?1 of salt (NaCl) concentration was required. Seeds of I. diffusa showed high viability (0.85) after 720 days of dry storage. Low emergence was recorded for seeds buried at 2 cm, and seedling emergence was completely inhibited when seeds were buried at 5 and 10 cm. Iresine diffusa seeds had high viability and were capable of emerging in a broad range of environmental conditions. The thermal germination conditions, shallow soil depths and high moisture conditions in germination phase for I. diffusa are congruent with the conditions in Argentina no‐tillage soyabean. Thus, no‐tillage could provide better conditions for germination than conventional tillage systems. However, due to the fact that I. diffusa can reproduce by rhizomes, further research should be conducted to understand the relative importance of the vegetative reproductive strategy in relation to the presence and persistence of this weed in fields. 相似文献