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101.
A Ferreira M C García Rodríguez F Ome?aca A Jiménez L M Villar P Gonzalez-Porqué G Fontán 《Clinical and experimental immunology》1991,84(1):167-169
In this work we have quantified soluble class I histocompatibility antigens (s-HLA) and beta 2-microglobulin (beta 2 m) in sera of HIV+ or HIV- mothers at delivery and in cord blood sera of their newborn children. The results obtained for beta 2 m show that cord blood sera of newborn children have higher concentrations than their mothers, implying that most of the beta 2 m in the newborn is self-produced as described previously. s-HLA serum concentrations in the newborn children are significantly lower than in their mothers or in age-matched controls. Moreover, HIV+ mothers have significantly higher serum concentrations than HIV- mothers or an age-matched control group. These results suggest that s-HLA does not cross the placental barrier. 相似文献
102.
Plana M Garcia F Oxenius A Ortiz GM Lopez A Cruceta A Mestre G Fumero E Fagard C Sambeat MA Segura F Miró JM Arnedo M Lopalcos L Pumarola T Hirschel B Phillips RE Nixon DF Gallart T Gatell JM 《Journal of acquired immune deficiency syndromes (1999)》2004,36(3):791-799
OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated. 相似文献
103.
Lymphoepithelioma-like carcinoma of the bladder: three cases with clinicopathological and p53 protein expression study 总被引:12,自引:0,他引:12
Izquierdo-García FM García-Díez F Fernández I Pérez-Rosado A Sáez A Suárez-Vilela D Guerreiro-González R Benéitez-Alvarez M 《Virchows Archiv : an international journal of pathology》2004,444(5):420-425
Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma. 相似文献
104.
The corpus callosum (CC) is the main white matter tract in the brain and is involved in interhemispheric communication. Using
the whole-cell voltage-clamp technique, a study was made of K+-currents in primary cultured astrocytes from the CC of newborn rats. These cells were positive to glial fibrillary acidic
protein after culturing in Dulbecco’s Modified Eagle Medium (> 95% of cells) or in serum-free neurobasal medium with G5 supplement
(> 99% of cells). Astrocytes cultured in either medium displayed similar voltage-activated ion currents. In 81% of astrocytes,
the current had a transient component and a sustained component, which were blocked by 4-aminopyridine and tetraethylammonium,
respectively; and both had a reversal potential of −66 mV, indicating that they were carried by K+ ions. Based on the Ba2+-sensitivity and activation kinetics of the K+-current, two groups of astrocytes were discerned. One group (55% of cells) displayed a strong Ba2+ blockade of the K+-current whose activation kinetics, time course of decay, and the current-voltage relationship were modified by Ba2+. This current was greatly blocked (52%) by Ba2+ in a voltage-dependent way. Another group (45% of cells) presented weak Ba2+-blockade, which was only blocked 24% by Ba2+. The activation kinetics and time course of decay of this current component were unaffected by Ba2+. These results may help to understand better the roles of voltage-activated K+-currents in astrocytes from the rat CC in particular and glial cells in general. 相似文献
105.
García Páez JM Jorge Herrero E Rocha A Martín-Maestro M Castillo-Olivares JL Millán I Carrera Sanmartín A Cordón A 《Journal of biomaterials applications》2002,17(2):105-123
Ostrich pericardium, sutured using a telescoping or overlapping technique, was studied to determine its mechanical behavior. From each of 12 pericardial sacs, four contiguous strips were cut longitudinally, from root to apex, and another four contiguous strips were cut in transverse direction. One of the strips in each set of four was used as an unsutured control and the remaining three were sutured by overlapping 0.5 cm of the tissue and sewing with Gore-tex, Prolene or Pronova. These 96 samples were then subjected to tensile testing along their major axes until rupture. The tensile stresses recorded in the suture materials at the moment tears appeared in the pericardium ranged between 55.99 MPa and 70.23 MPa for Gore-tex in samples cut in the two directions. Shear stress became ostensible at 56 MPa, with clearly evident tears. However, microfracture of the collagen fibers must be produced at much lower stress levels. The comparison of the resistance in kilograms (machine-imposed), without taking into account the sections in which the load was applied, demonstrated only a slight loss of load when the telescoping suture was employed in ostrich pericardium samples. Ostrich pericardium may continue to be an alternative biological material for the construction of heart valve leaflets. 相似文献
106.
INK4a/ARF locus alterations in human non-Hodgkin's lymphomas mainly occur in tumors with wild-type p53 gene 总被引:3,自引:0,他引:3 下载免费PDF全文
Pinyol M Hernández L Martínez A Cobo F Hernández S Beà S López-Guillermo A Nayach I Palacín A Nadal A Fernández PL Montserrat E Cardesa A Campo E 《The American journal of pathology》2000,156(6):1987-1996
INK4a/ARF locus codes for two different proteins, p16(INK4a) and p14(ARF), involved in cell cycle regulation. p14(ARF) is considered an upstream regulator of p53 function. To determine the role of these genes in the pathogenesis of human non-Hodgkin's lymphomas we have analyzed exon 1beta, 1alpha, and 2 of the INK4a/ARF locus and p53 gene aberrations in 97 tumors previously characterized for p16(INK4a) alterations. p53 alterations were detected in four of 51 (8%) indolent lymphomas but in 15 of 46 (33%) aggressive tumors. Inactivation of p14(ARF) was always associated with p16(INK4a) alterations. Exon 1beta was concomitantly deleted with exon 1alpha and 2 in eight tumors. One additional lymphoblastic lymphoma showed deletion of exon 1alpha and 2 but retained exon 1beta. No mutations were detected in exon 1alpha and 1beta in any case. Two of the three mutations detected in exon 2 caused a nonsense mutation in the p16(INK4a) reading frame and a missense mutation in the ARF reading frame involving the nucleolar transport domain of the protein. The third mutation was a missense mutation in the p16(INK4a) reading frame, but it was outside the coding region of p14(ARF). Aggressive lymphomas with p14(ARF) inactivation and p53 wild type showed a significantly lower p53 protein expression than tumors with no alteration in any of these genes. In this series of tumors, inactivation of the INK4a/ARF locus mainly occurred in tumors with a wild-type p53 gene because only two lymphomas showed simultaneous aberrations in these genes. Tumors with concomitant alterations of p16(INK4a) and p14(ARF)/p53 genes seem to exhibit a worse clinical behavior than lymphomas with no alterations or isolated inactivation of any of these genes. These findings indicate that p14(ARF) genetic alterations occur in a subset of aggressive NHLs, but they are always associated with p16(INK4a) aberrations. Concomitant disruption of p16(INK4a) and p14(ARF)/p53 regulatory pathways may have a cooperative effect in the progression of these tumors. 相似文献
107.
Federico Ferrando-Castagnetto Enrique Macri Alejandro Silva Darío Padula Gastón Garcés 《Educación Médica》2019
Introduction
Although an objective structured clinical examination (OSCE) format has been applied in Uruguay since 2004, and providing reliable performance measures, perceptions of it properties and level of student satisfaction have not been determined.Objective
To evaluate the face validity of OSCE format as a contribution to its local feasibility study.Material and methods
At the end of the introductory clinical course, the sub-cohort enrolled at the University Hospital responded to a 28-item questionnaire aimed at exploring perceptions about the properties of the OSCE about the potential factors ‘design’ and ‘apparent validity’. After analysing the reliability of the original questionnaire, the questionnaire was refined in an attempt to provide a shorter and more reliable tool.Results
The original questionnaire showed good internal consistency (Cronbach alpha = 0.70), with a dominance of ‘agreement/total agreement’ opinions on authenticity of the stimuli, dynamic, relevance, and equity of the test. Students perceived organisational obstacles during the test, expressing disagreement to include some stations only aimed at assessing communication skills, and requiring personalised feedback sessions. The refined version of the questionnaire provides consistent measures on student perceptions and is a useful tool that can be widely applied. A discussion is presented on the contributions of this experience to a comprehensive feasibility study of the new format during curriculum transition.Conclusions
The OSCE is well evaluated by students at the end of the propaedeutic course, supporting its validity. Educational potentials of the new format should be exploited, providing effective feedback to students, clinical teachers, and institutions. 相似文献108.
Soft-tissue angiomatosis is a rare condition characterized by diffuse proliferation of benign vascular structures, accompanied by mature adipose tissue, which affect a large segment of the body in a contiguous fashion. Most patients present in childhood or adolescence. We report a case of large soft-tissue angiomatosis, located in the left forearm of a 65-year-old man, which showed extensive intramuscular and intermuscular infiltration, and embracement of the radius and the main vascular and neural bundles of the forearm. Due to the deep location, large size, ill-defined limits and non-homogeneous composition with areas suggestive of an adipose component in the radiological examination, the lesion raised the possibility clinically of a liposarcoma. The myxoid adipose tissue component of the lesion, a feature previously undescribed, and the predominance of small, capillary-sized vessels were considered concordant with the clinical diagnosis. This presentation is rare. The features of the lesion made complete surgical excision impossible and amputation of the extremity was considered the best treatment. The main differential diagnoses include infiltrating lipoma, myxolipoma, angiomyxolipoma, angiolipoma, intramuscular angioma, liposarcoma and low-grade myxofibrosarcoma. In conclusion, angiomatosis might simulate liposarcoma, particularly if the mass is large, heterogeneous, myxoid and appears later in life. 相似文献
109.
Romero Gómez MP Peinado Esteban AM Sobrino Daza JA Sáez Nieto JA Alvarez D Peña García P 《Journal of clinical microbiology》2004,42(7):3371-3373
We describe a case of infective endocarditis in a prosthetic mitral valve due to Ochrobactrum anthropi. Although O. anthropi is an emerging pathogen in immunocompromised patients, infections with the bacterium have very rarely been documented in healthy hosts, and endocarditis is rare. To our knowledge, only two cases of O. anthropi endocarditis have been reported in the medical literature. 相似文献
110.
García-González M Abdulkader I Boquete AV Neo XM Forteza J Cameselle-Teijeiro J 《Virchows Archiv : an international journal of pathology》2005,447(1):12-17
This study was undertaken to investigate cyclooxygenase-2 (COX-2) expression in follicular cells of the human thyroid. COX-2 expression was studied immunohistochemically in a total of 174 samples. COX-2 immunoreactivity was confined to the cell cytoplasm with the nuclei remaining unlabelled. COX-2 expression was observed in five cases (17.2%) of normal follicular cells and in one case (16.6%) of solid cell nests. Follicular carcinoma expressed COX-2 more frequently than follicular adenoma (93.4% vs 21.1%) (p0.001). A higher percentage of cases of papillary microcarcinomas up-regulated COX-2 in comparison with all papillary carcinomas (p0.05). However, we could not establish any relationships among COX-2, patients ages or lymph node metastases in papillary carcinomas. COX-2 expression was found in 12 (92.3%) poorly differentiated carcinomas and in 13 (92.8%) undifferentiated carcinomas. We found that COX-2 is not always useful as a marker of malignancy. Our results suggest that COX-2 plays a role in progression of all thyroid carcinomas, but in papillary carcinomas, seems more important only in the early stages. COX-2 expression in the undifferentiated carcinoma deserves special consideration due to its prognosis and to the fact that selective COX-2 inhibitors were found to enhance tumour response to radiation in some studies. 相似文献