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31.
Ismael Hernández-Torres Magdalena Iracheta Luis J. Galán-Wong Carlos Hernández Juan Contreras Mark Jackson Benito Pereyra-Alférez 《World journal of microbiology & biotechnology》2004,20(2):207-210
A Paecilomyces fumosoroseus strain was mutagenized by u.v. Among 200 colonies, one mutant (M84), showed a large and stable chitin hydrolysis-halo. Glucose consumption and biomass production were similar for M84 and the parental strain. Chitinase was inducible by chitin and repressed by glucose in both strains but, when they were grown on minimal medium plus colloidal chitin as sole carbon source, the parental and M84 strains yielded 198 and 690 mol N-acetylglucosamine, respectively. This results indicate that the mutant strain synthesized a chitinase with a higher activity. Bioassays against Bemisia tabaci nymph, showed that M84 incited a 2-fold higher incidence of disease compared to the parental strain. 相似文献
32.
Carlos A Aguilar-Salinas Andréia Assis-Luores-Vale Benjamín Stockins Hector Mario Rengifo Dondici José Filho Abrahão Afiune Neto Marcílio Lísia Rabelo Kerginaldo Paulo Torres Egídio Paulo de José Oliveira Carlos Alberto Machado Eliana Reyes Victor Saavedra Fernando Florenzano Ma Victoria Hernández Hernandez Sergio Jiménez Erika Ramírez Cuauhtémoc Vazquez Saul Salinas Ismael Hernández Octavio Medel Ricardo Moreno Paula Lugo Ricardo Alvarado Roopa Mehta Victor Gutierrez Francisco J Gómez Pérez 《Cardiovascular diabetology》2004,3(1):1-6
Background
Microalbuminuria and subsequent progression to proteinuria and nephropathy is associated with increased oxidative stress, increased inflammatory cytokines and increased cardiovascular (CVD) risk. The common functional IL-6 -174G>C gene variant is also associated with elevated levels of inflammatory cytokines and CVD risk.Methods
The aim of this study was to examine the association between the IL-6 -174G>C gene variant with plasma total antioxidant status (TAOS) in 552 subjects with type 2 diabetes in relation to urinary protein excretion.Results
In subjects free from CVD, there was a significant interaction between urinary protein excretion (normoalbuminuria/ microalbuminuria/proteinuria) and the -174C allele (compared to -174GG) in determining plasma TAOS (p value for interaction = 0.03). In the -174C allele carriers there was a significant association between plasma TAOS and urinary protein excretion: normalbuminuria v microalbuminuria v proteinuria: 44.30% ± 11.32 vs. 39.74% ± 14.83 vs. 37.93% ± 16.42, ANOVA p = 0.025. In those with CVD, no interaction or association was observed with the -174C allele (p = 0.246).Conclusion
The IL-6 -174G>C gene variant is associated with differences in plasma oxidative stress in response to altered protein excretion in subjects with type 2 diabetes. 相似文献33.
Chitosan induces different L-arginine metabolic pathways in resting and inflammatory macrophages 总被引:7,自引:0,他引:7
Porporatto C Bianco ID Riera CM Correa SG 《Biochemical and biophysical research communications》2003,304(2):266-272
Chitosan is a linear polymer of N-acetyl-D-glucosamine and deacetylated glucosamine widely used as a wound-healing accelerator in clinical and veterinary medicine. Chitosan enhances the functions of inflammatory cells such as macrophages (Mphi), inducing the production of cytokines as well as the expression of activation markers, Fc receptors and mannose receptor. In this work we studied the effects of chitosan on the arginine metabolic pathways of both resident and inflammatory (proteose-peptone elicited) rat Mphi. Our results show that low molecular weight (LMW) chitosan activated moderately both the inducible nitric oxide synthase (iNOS) and arginase pathways in resident Mphi. In inflammatory Mphi treated with chitosan instead, the arginase activity was strongly enhanced. Supernatants of chitosan-stimulated Mphi enhanced the proliferation of the rat cell line C6. These findings suggest that the healing activity of chitosan could rely on the enhanced arginase activity observed in a wound-associated inflammatory milieu. 相似文献
34.
35.
PTB-associated splicing factor (PSF) has been implicated in both early and late steps of pre-mRNA splicing, but its exact role in this process remains unclear. Here we show that PSF interacts with p54nrb, a highly related protein first identified based on cross-reactivity to antibodies against the yeast second-step splicing factor Prpl8. We performed RNA-binding experiments to determine the preferred RNA-binding sequences for PSF and p54nrb, both individually and in combination. In all cases, iterative selection assays identified a purine-rich sequence located on the 3' side of U5 snRNA stem 1b. Filter-binding assays and RNA affinity selection experiments demonstrated that PSF and p54nrb bind U5 snRNA with both the sequence and structure of stem 1b contributing to binding specificity. Sedimentation analyses show that both proteins associate with spliceosomes and with U4/U6.U5 tri-snPNP. 相似文献
36.
The importance of microscopic examination in the management of desquamative diseases of the scalp 总被引:3,自引:0,他引:3
After determining the usual malassezic biota of the scalp in adult, normal persons, 259 patients with different desquamative
diseases were studied by a simple adhesive tape technique. The main purpose of this study was to investigate the utility of
this technique to improve the diagnosis and treatment of patients. Most patients with seborrhoeic dermatitis and sebopsoriasis
demonstrated large numbers of {it Malassezia} spp. cells corresponding to the so called ``pityrosporosis'. Only 43.6% of
patients with pityriasis capitis (dandruff) presented with such a diagnosis. Symptomatic pityrosporosis of the scalp should
be treated with imidazolic derivatives or other antifungal substances. Patients with psoriasis of the scalp showed a typical
microscopic picture represented by parakeratosic (nucleated) keratinocytes with absence of lipophilic yeasts which should
be attributed to the usual dryness of the scales .Microbial epidermitis (eczema) of the scalp revealed another characteristic
picture constituted by abundant leukocytes and bacteria without the presence of yeasts. The different microscopic pictures
seen with this simple technique for diseases of the scalp, offer an adjunct to make a proper diagnosis and to establish a
convenient treatment in cases which are not clinically well defined.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
37.
Qin C Nguyen T Stewart J Samudio I Burghardt R Safe S 《Molecular endocrinology (Baltimore, Md.)》2002,16(8):1793-1809
38.
Structural differences between the repertoires of mouse and human germline genes and their evolutionary implications 总被引:1,自引:0,他引:1
J. C. Almagro Ismael Hernández Maria Carmen Ramírez Enrique Vargas-Madrazo 《Immunogenetics》1998,47(5):355-363
Although human and mouse antibodies are similar when one considers their diversification strategies, they differ in the extent
to which kappa and lambda light chains are present in their respective variable light chain repertoires. While the Igk-V germline genes are preponderant in mice (95% or more), they comprise only 60% in humans. This may account for differences
in the structural repertoire encoded in the Igk-V germline genes of these species. However, this subject has not been properly investigated, partially because a systematic
structural characterization of the mouse Igk-V germline genes has not been undertaken. In the present study we compiled all available information on mouse Igk-V germline genes to characterize their structural repertoire. As expected, comparison with the structural repertoire of human
Igk-V germline genes indicates differences. The most interesting is that the mouse Igk-V germline gene repertoire is more diverse in structural terms than its human counterpart: the mouse encodes seven canonical
structure classes (combination of canonical structures in L1 and L3). In contrast, the human encodes only four. Analysis of
the evolutionary relationships of human and mouse Igk-V germline genes led us to propose that the difference reflects a strategy of mice to compensate for the small lambda chain
contribution to the repertoire of their variable light chains.
Received: 1 June 1997 / Revised: 6 October 1997 相似文献
39.
Ismael Palacios-García Ariel Lara-Vásquez Juan F. Montiel Gabriela F. Díaz-Véliz Hugo Sepúlveda Elías Utreras Martín Montecino Christian González-Billault Francisco Aboitiz 《PloS one》2015,10(2)
Prenatal stress causes predisposition to cognitive and emotional disturbances and is a risk factor towards the development of neuropsychiatric conditions like depression, bipolar disorders and schizophrenia. The extracellular protein Reelin, expressed by Cajal-Retzius cells during cortical development, plays critical roles on cortical lamination and synaptic maturation, and its deregulation has been associated with maladaptive conditions. In the present study, we address the effect of prenatal restraint stress (PNS) upon Reelin expression and signaling in pregnant rats during the last 10 days of pregnancy. Animals from one group, including control and PNS exposed fetuses, were sacrificed and analyzed using immunohistochemical, biochemical, cell biology and molecular biology approaches. We scored changes in the expression of Reelin, its signaling pathway and in the methylation of its promoter. A second group included control and PNS exposed animals maintained until young adulthood for behavioral studies. Using the optical dissector, we show decreased numbers of Reelin-positive neurons in cortical layer I of PNS exposed animals. In addition, neurons from PNS exposed animals display decreased Reelin expression that is paralleled by changes in components of the Reelin-signaling cascade, both in vivo and in vitro. Furthermore, PNS induced changes in the DNA methylation levels of the Reelin promoter in culture and in histological samples. PNS adult rats display excessive spontaneous locomotor activity, high anxiety levels and problems of learning and memory consolidation. No significant visuo-spatial memory impairment was detected on the Morris water maze. These results highlight the effects of prenatal stress on the Cajal-Retzius neuronal population, and the persistence of behavioral consequences using this treatment in adults, thereby supporting a relevant role of PNS in the genesis of neuropsychiatric diseases. We also propose an in vitro model that can yield new insights on the molecular mechanisms behind the effects of prenatal stress. 相似文献