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31.
32.
Desantis S Corriero A Acone F Zubani D Cirillo F Palmieri G De Metrio G 《Acta histochemica》2003,105(1):73-79
Expression of sugar residues and the nature of oligosaccharide linkage during keratinocyte maturation in the epidermis of the Breton dog were studied with the use of lectin histochemistry. Thirteen lectins were used. Labelling was not observed with GSA I-B4, GSA II, UEA-I, and LTA. The cytoplasm of keratinocytes reacted with PNA, HPA, Con A, and WGA from the basal layer to the granular layer. PNA and Con A showed highest reactivity in the granular cell layer. The cell surface showed increased reactivity with PNA, HPA, and WGA with maturation of keratinocytes. KOH-neuraminidase treatment (KOH-Neu) increased PNA and RCA120 staining during keratinocyte differentiation thus indicating an increase in oligosaccharides terminating with sialic acid-Galbeta(1,3)GalNAc and sialic acid-Galbeta(1,4)GlcNAc, respectively. Labelling of the glycocalyx of basal and spinous keratinocytes with SNA and MAA revealed terminal Neu5acalpha(2,6)Gal/GalNAc and Neu5acalpha(2,3)Galbeta(1,4)GlcNAc. KOH-Neu-DBA showed oligosaccharides terminating with sialic acid-GalNAcalpha(1,3)GalNAc in the spinous and granular layers. A selective glycocalyx labelling of granular keratinocytes was observed with DBA and SBA. Reactions with MAA, PNA, DBA, RCA120, SBA, HPA, and WGA disappeared after the beta-elimination reaction. Our findings indicate that Breton dog epidermis contains more O-linked than N-linked oligosaccharides and confirm that different subpopulations of keratinocytes can be distinguished by lectin histochemistry. 相似文献
33.
During the past 10 years knowledge about the interactions between major histocompatibility complex (MHC) class I molecules
and the T-cell receptor (TCR) complex of cytotoxic T-cells (CTL) has developed dramatically. But the primary interest, both
with respect to structure as well as function, has concentrated on HLA-A and -B molecules because of their high sequence polymorphism
and their dominating presence at the cell surface. In contrast, HLA-C molecules seemed to be of only minor importance in the
cascade of immune reactions owing to their more limited polymorphism and reduced levels of surface expression. The inability
to define a number of antigen specificities had the result that HLA-C molecules were often neglected in studies of immune
response, transplantation, and disease association. More recently a new function has been identified for HLA class I molecules
where they act as inhibitors of the lytic capacity of natural killer (NK) cells and non-MHC-restricted T-cells. Moreover,
the understanding of this novel mode of negative regulation of cytotoxicity was remarkably influenced by HLA-C since these
were the first HLA class I molecules found to have such inhibitory potential. With this new inhibitory function serving as
an essential component of the immune system, HLA-C molecules can no longer be neglected. 相似文献
34.
Marqué S Poirel L Héritier C Brisse S Blasco MD Filip R Coman G Naas T Nordmann P 《Journal of clinical microbiology》2005,43(9):4885-4888
The spread of the plasmid-mediated carbapenem-hydrolyzing oxacillinase OXA-58 was detected in Acinetobacter sp. clinical isolates from southern Europe, the Balkans, and central Turkey. It may contribute significantly to the emergence of carbapenem resistance in Acinetobacter spp., at least in this part of the world. 相似文献
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36.
Fishery products are the main source of dietary n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Following the European Commission’s request to address the risks and benefits of seafood consumption, and taking into account the great variability of nutrient and contaminant levels in fishery products, the present work aims to estimate the n-3 LC-PUFA provided per serving of selected fishes, shrimps and mollusks that are commonly consumed in Spain. This would enable the establishment of a risk–benefit analysis of fish consumption and provide recommendations for fish intake to comply with nutritional guidelines of n-3 LC-PUFA intake. We confirmed high variation in the pattern and contents of fatty acids for different species. n-6 PUFA were minor fatty acids, whereas palmitic (C16:0), oleic (C18:1 n-9), and mainly eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids were the major fatty acids in the sample. Therefore, consumption of 2–3 servings per week of a variety of fishery products may contribute to compliance with the recommended daily n-3 LC-PUFA intake while maintaining an adequate balance to avoid contaminant-derived potential risks (metals and others). Taking the fatty acid content of fishery products described in this study into consideration, it is advisable to include one serving of fatty fish per week in order to meet recommended n-3 LC-PUFA levels. 相似文献
37.
M. Dolores del Toro López Javier Arias Díaz José M. Balibrea Natividad Benito Andrés Canut Blasco Erika Esteve Juan Pablo Horcajada Juan Diego Ruiz Mesa Alba Manuel Vázquez Cristóbal Muñoz Casares Jose Luis del Pozo Miquel Pujol Melchor Riera Jaime Jimeno Inés Rubio Pérez Jaime Ruiz-Tovar Polo Alejandro Serrablo Alex Soriano Josep M. Badia 《Cirugía espa?ola》2021,99(1):11-26
Antibiotic prophylaxis in surgery is one of the most effective measures for preventing surgical site infection, although its use is frequently inadequate and may even increase the risk of infection, toxicities and antimicrobial resistance. As a result of advances in surgical techniques and the emergence of multidrug-resistant organisms, the current guidelines for prophylaxis need to be revised.The Sociedad Española de Enfermedades Infecciosas (Spanish Society of Infectious Diseases and Clinical Microbiology) (SEIMC) together with the Asociación Española de Cirujanos (Spanish Association of Surgeons) (AEC) have revised and updated the recommendations for antibiotic prophylaxis in surgery to adapt them to any type of surgical intervention and to current epidemiology. This document gathers together the recommendations on antimicrobial prophylaxis in the various procedures, with doses, duration, prophylaxis in special patient groups, and in epidemiological settings of multidrug resistance to facilitate standardized management and the safe, effective and rational use of antibiotics in elective surgery. 相似文献
38.
39.
Salcedo M Taja L Utrera D Chávez P Hidalgo A Pérez C Benítez L Castañeda C Delgado R Gariglio P 《International journal of experimental pathology》2002,83(6):275-286
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma. 相似文献
40.
Joanna Luczkowiak Gonzalo Rivas Nuria Labiod Fátima Lasala Marta Rolo Jaime Lora-Tamayo Mikel Mancheno-Losa David Rial-Crestelo Alfredo Pérez-Rivilla María Dolores Folgueira Rafael Delgado 《Journal of medical virology》2023,95(1):e28268
We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID-19 naïve and convalescent individuals. Third doses of mRNA COVID-19 vaccines induced a significant increase in potency and breadth of neutralization against SARS-CoV-2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross-neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID-19 convalescents except for BA.4/5. Avidity of RBD-binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS-CoV-2 sequences are required to induce high avidity cross-neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments. 相似文献