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71.
Xavier Sastre‐Garau Jrme Couturier Josette Derr Alain Aurias Jerzy Klijanienko Ral Lagac 《The Journal of pathology》2002,196(1):97-102
Inflammatory myofibroblastic tumours (IMTs) were initially considered to be benign reactive processes, but cases with an unfavourable outcome have been reported. Moreover, clonal genetic alterations have recently been published in some cases, suggesting that IMT may represent a malignant neoplastic entity. This paper reports a case of IMT that developed in the mammary gland, an unusual site. The histological picture was characterized by a proliferation of spindle cells with little cellular atypia and rare mitoses, associated with a polymorphous inflammatory infiltrate. Their immunophenotype, characterized by the expression of vimentin, smooth muscle actin, and cytokeratins, corresponded to that of myofibroblasts. Cytogenetic analysis revealed the clonal nature of the lesion. The modal karyotype was 48, X, ins(2;X)(q34;p21.2p22.2), +7, del(9)(p23), +19. Including the present observation, a 9p deletion has now been found in three cases of IMT. These observations show that IMT may be a clonal neoplasm, even in sites different from deep soft tissues. 相似文献
72.
Mello MA Mascarenhas RE Ferraro GA Harn D Galvão-Castro M Bou-Habib DC 《Medical microbiology and immunology》2005,194(1-2):61-65
Patients infected with HIV-1 develop a potent humoral immune response against the virus, but HIV-1 primary isolates are remarkably resistant to neutralizing antibodies. Considering that the envelope glycoprotein of HIV-1 (gp120/41) is heavily glycosylated, we investigated whether anti-carbohydrate antibodies could inhibit HIV-1 infection in vitro. We studied the neutralizing activity of three monoclonal antibodies (mAbs) raised to carbohydrates of Schistosoma mansoni, against seven primary isolates of HIV-1. Assays were performed infecting peripheral blood mononuclear cells from normal donors with viral isolates previously treated with mAbs. Viral strains used were tropic for the coreceptors CCR5, CXCR4, and dual-tropic ones. We found that the anti-glycan mAbs vigorously inhibited HIV-1 infection, regardless of the preferential coreceptor usage of the isolate, in a dose-response manner. Importantly, five isolates were resistant to neutralization by two HIV-1 antibody-positive human sera endowed with potent anti-HIV-1 inhibitory activity. Our findings suggest that carbohydrates of the HIV-1 viral envelope may be a target of an effective humoral immune response elicited by vaccination.The first two authors contributed equally to this work 相似文献
73.
Characterization of conserved T- and B-cell epitopes in Plasmodium falciparum major merozoite surface protein 1 下载免费PDF全文
Parra M Hui G Johnson AH Berzofsky JA Roberts T Quakyi IA Taylor DW 《Infection and immunity》2000,68(5):2685-2691
Vaccines for P. falciparum will need to contain both T- and B-cell epitopes. Conserved epitopes are the most desirable, but they are often poorly immunogenic. The major merozoite surface protein 1 (MSP-1) is currently a leading vaccine candidate antigen. In this study, six peptides from conserved or partly conserved regions of MSP-1 were evaluated for immunogenicity in B10 congenic mice. Following immunization with the peptides, murine T cells were tested for the ability to proliferate in vitro and antibody responses to MSP-1 were evaluated in vivo. The results showed that one highly conserved sequence (MSP-1#1, VTHESYQELVKKLEALEDAV; located at amino acid positions 20 to 39) and one partly conserved sequence (MSP-1#23, GLFHKEKMILNEEEITTKGA; located at positions 44 to 63) contained both T- and B-cell epitopes. Immunization of mice with these peptides resulted in T-cell proliferation and enhanced production of antibody to MSP-1 upon exposure to merozoites. MSP-1#1 stimulated T-cell responses in three of the six strains of mice evaluated, whereas MSP-1#23 was immunogenic in only one strain. Immunization with the other four peptides resulted in T-cell responses to the peptides, but none of the resulting peptide-specific T cells recognized native MSP-1. These results demonstrate that two sequences located in the N terminus of MSP-1 can induce T- and B-cell responses following immunization in a murine model. Clearly, these sequences merit further consideration for inclusion in a vaccine for malaria. 相似文献
74.
Enrique Fernández-Caldas Jerónimo Carnés Víctor Iraola Miguel Casanovas 《Annals of allergy, asthma & immunology》2007,98(5):464-470
BACKGROUND: Numerous varieties of Olea europaea have been described in Mediterranean countries. OBJECTIVE: To investigate the immunochemical characteristics of 6 varieties of Olea europaea collected during 5 consecutive years. METHODS: The varieties Carrasquefio, Manzanillo, Acebuche (wild olive), Hojiblanco, Picual, and Nevado were analyzed. Pollen samples from each variety were collected for 5 consecutive years from the same cultivars by trained personnel. The antigenic and allergenic profiles of these extracts were evaluated by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot using the serum of 29 O. europaea-allergic individuals. Ole e 1 was measured using enzyme-linked immunosorbent assay and purified Ole e 1 and rabbit polyclonal antibodies. Allergenic potency was determined using enzyme-linked immunosorbent assay inhibition and is expressed in histamine equivalent prick units per gram of raw material. RESULTS: Hojiblanco and Acebuche had the lowest mean +/- SD Ole e 1 content in the 5 years (0.045 +/- 0.029 and 0.059 +/-0.031 microg/microg of freeze-dried material, respectively). The variety with the highest mean +/- SD Ole e 1 content was Picual (0.19 +/-0.075 microg/microg). Hojiblanco had the lowest total biological potency throughout the study. A positive correlation was obtained between rainfall in the winter months and total allergenicity of the 6 varieties. CONCLUSIONS: The different varieties of O. europaea pollen demonstrated great differences in allergenic potency and Ole e 1 content. These differences were maintained throughout the study, suggesting that they are due to genetic differences intrinsic to the varieties, although certain climatic effects may also play a role. 相似文献
75.
Aberrant cellular retinol binding protein 1 (CRBP1) gene expression and promoter methylation in prostate cancer 总被引:3,自引:0,他引:3 下载免费PDF全文
Jerónimo C Henrique R Oliveira J Lobo F Pais I Teixeira MR Lopes C 《Journal of clinical pathology》2004,57(8):872-876
AIMS: Retinoids are involved in cell growth, differentiation, and carcinogenesis. Their effects depend on cytosolic transport and binding to nuclear receptors. CRBP1 encodes a protein involved in this process. Because altered CRBP1 expression and promoter hypermethylation occur in several tumours, these changes were investigated in prostate tumorigenesis. METHODS: The CRBP1 promoter was assessed by methylation specific polymerase chain reaction on tissue samples from 36 radical prostatectomy specimens (paired normal tissue, adenocarcinoma, and high grade prostatic intraepithelial neoplasia (HGPIN)), 32 benign prostatic hyperplasias (BPHs), and 13 normal prostate tissue samples from cystoprostatectomies. Methylation of DNA extracted from microdissected tissue was examined blindly. CRBP1 expression was assessed by immunohistochemistry on formalin fixed, paraffin wax embedded tissue. RESULTS: Loss of CRBP1 expression was seen in 15 of 36 adenocarcinomas and 18 of 36 HGPINs. Fifteen adenocarcinomas and nine HGPINs showed overexpression, whereas the remainder showed normal expression. BPH displayed normal expression. No significant associations were found between CRBP1 expression and Gleason score or stage. CRBP1 promoter hypermethylation was found in 17 of 36 adenocarcinomas, three of 35 HGPINs, one of 36 normal prostate tissues from the same patients, none of 32 BPHs, and none of 13 normal prostate tissues from cystoprostatectomies. Loss of expression and hypermethylation of CRBP1 were not significantly associated. CONCLUSIONS: Altered CRBP1 expression and hypermethylation are common in prostate carcinoma, although CRBP1 hypermethylation is not an early event in tumorigenesis. Moreover, both adenocarcinoma and HGPIN show frequent CRBP1 overexpression. The molecular mechanisms underlying altered CRBP1 expression in prostate cancer deserve further study. 相似文献
76.
77.
Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献
78.
Dr. L. Kutinová Š. Němečková E. Hamšíková M. Press H. Závadová I. Hirsch V. Němeček V. Krchňák J. Smrt D. Slonim V. Vonka 《Archives of virology》1990,112(3-4):181-193
Summary Several vaccinia virus recombinants inducing the synthesis of the middle surface (M) protein of hepatitis B virus (HBV) were constructed. One of them, denoted vl37, was examined in some detail. The virus replicated nearly to the same extent in various cell lines, viz. human embryo diploid fibroblast LEP and MRC-5 cells, rabbit embryo fibroblast REF cells, TK– rat RAT-2 cells, and green monkey CV-1 cells. However, the production of M protein was found considerably lower in the human LEP and MRC-5 than in the other cells examined. In addition, the kinetics of M formation were different in these two cell systems, LEP cells lagging significantly behind CV-1 cells. The low-level production of M protein in LEP cells was not increased by repeated vl37 passages in LEP cells, nor by a passage in a laboratory worker accidentally infected with the vl37 virus, nor by shortening the leader sequence preceding the translation initiation codon. The greater part of the M antigen was found to be cell associated, more so in the cells of human than monkey origin. From the major HBV S antigen (HBsAg) isolated from the plasma of chronically infected subjects, the antigen released by cell destruction differed by binding to polymerized human albumin. This property was utilized in ELISA to detect anti-preS2 antibody. Rabbits inoculated intradermally with the vl37 virus developed antibodies reactive in this assay as well as with a synthetic peptide corresponding in the amino acids 14–34 of the NH2terminus of the HBsAg preS2 region. 相似文献
79.
Jér?me Jacques Maude Bouscambert-Duchamp Hélène Moret Jocelyne Carquin Véronique Brodard Bruno Lina Jacques Motte Laurent Andréoletti 《Journal of clinical virology》2006,35(4):463-466
BACKGROUND: Human rhinoviruses and enteroviruses (Picornaviridae) are suspected to be major viral etiological causes of bronchiolitis in infants. OBJECTIVES: In the present study, we assessed the potential role of the respiratory picornaviruses as causative agents of bronchiolitis in French infants. STUDY DESIGN: From September 2001 to June 2002, we prospectively selected 192 infants < or =36 months of age and hospitalized for acute bronchiolitis. The detection of common respiratory viruses (respiratory syncytial virus, influenza virus A and B, parainfluenza virus 1, 2, 3 and adenovirus) was performed using classical immunofluorescence antigen and cell-culture detection assays on nasopharyngeal aspirates whereas the detection of human metapneumovirus (HMPV) was performed by a real-time RT-PCR assay. The presence of rhinovirus and/or enterovirus was assessed in respiratory samples by a picornavirus RT-PCR detection assay followed by a differential Southern blotting procedure. RESULTS: A potential causative virus was detected in 72.5% of the 192 study infants. RSV (30%), rhinovirus (21%), enterovirus (9%), influenza virus A (6%) and human metapneumovirus (4%) were the most frequent causative agents detected. Rhinoviruses or enteroviruses were detected as the only evidence of respiratory viral tract infection in 57 (30%) of 192 infants, whereas rhinovirus or enterovirus occurred in mixed viral infection detected in 25 (13%) of 192 study cases (30% versus 13%, p<10(-3)). CONCLUSIONS: Our data suggest that respiratory picornaviruses are one of the leading etiological causes of bronchiolitis in French infants. These findings highlight the need to implement a rapid picornavirus RT-PCR detection assay for the clinical diagnosis of respiratory infections in pediatric patients with bronchiolitis. 相似文献
80.
Jarmila Kruseová Jelena Černíková Marina Zámečníková Lucie Hřivnová Stanislava Koloušková Michaela Čepelová Edita Kabíčková Václav Čapek Aleš Lukš Tomáš Eckschlager 《Andrologia》2021,53(1):e13853
The objective of this study was to compare semen quality (sperm density, progressive motility and spermia) between long-term childhood cancer survivors and a control group of males. The second objective was to correlate the semen analysis of the survivors with cancer treatment and endocrine status. The semen quality of 143 survivors (median age, 23.6 years) was compared to 200 men (median age, 27.9 years) who had not been diagnosed with cancer. The cancer-related risk factors and gonadotrophin levels were compared. Overall, 65% of the survivors had abnormal semen analysis compared to 26.5% of the controls (p < 0.0001). Survivors with nonaspermia had lower sperm density than the controls (p < 0.001). Other observed correlations were not significant. Survivors who were treated with alkylating agents were more likely to have abnormal semen analysis (p < 0.008). Follicle-stimulating hormone and luteinising hormone levels were significantly elevated (p < 0.0001) in survivors with abnormal semen analysis. The semen quality parameters, except for low sperm density, did not differ in survivors with nonaspermia compared to the controls. The risk factors included treatment with alkylating agents. Elevated gonadotrophin levels correlated with abnormal semen analysis. All cancer survivors should be made aware of the possibility of suffering from cancer treatment-related infertility. 相似文献