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21.
Gil-Benso R Lopez-Gines C López-Guerrero JA Carda C Callaghan RC Navarro S Ferrer J Pellín A Llombart-Bosch A 《Laboratory investigation; a journal of technical methods and pathology》2003,83(6):877-887
Chondrosarcomas are malignant cartilage-forming tumors that represent the second most common malignant solid tumor of bone. These biologically poorly understood neoplasms vary considerably in clinical presentation and biologic behavior. Chemotherapy and radiation therapy are generally ineffective. Here we describe the establishment and characterization of a new human chondrosarcoma cell line named ch-2879, and we compare the cell line with its tumor of origin. The cell line was established from a recurrent grade 3 chondrosarcoma of the chest wall and characterized by growth kinetics and morphologic studies. Immunocytochemistry and RT-PCR were performed to examine the expression of cartilage-specific phenotypes. Genetic characterization was performed using cytogenetics, fluorescence in situ hybridization, flow cytometry, and molecular techniques for analysis of the genes implicated in cell cycle control, amplification of MDM2, CDK4, and Cyclin D1, and mutations in the p53 gene. ch-2879 cells were subcultured for more than 80 passages. They expressed vimentin, HNK-1, HBA-71, Ki-67, cyclin D1, Fli-1, S-100, p21, p27, and p53 and were negative for cytokeratin, EMA, p14, p16, MDM2, Rb, and c-erb-b2 antigens. Cytogenetically the recurrent tumor showed a hyperhaploid karyotype with clonal numerical and structural abnormalities. The sole structural abnormality was a chromosome derivative of a t(1;21) translocation. The cell line at passage 3 showed two populations: the hyperhaploid and an exactly duplicated, hypotriploid population. After the 18th passage, only the hypotriploid population was present. The cells expressed collagen 2. Molecular comparison of the primary and recurrent tumor evidenced an in vivo molecular change consisting of a deletion of 9p21 genes in the recurrence, probably caused by a selection process. Because of its gene expression profile, including expression of genes implicated in chondrogenesis in uncoated plastic dishes, this cell line may prove useful for cellular and molecular studies as well as studies of chondrosarcoma characterization and treatment. 相似文献
22.
E.G. De la Concha M. Fernandez-Arquero J.L. Mendoza L. Conejero M.A. Figueredo J. Perez de la Sema M. Diaz-Rubio A. Ruiz de Leon 《Tissue antigens》1998,52(4):381-384
Abstract: Achalasia is a motor disorder of the esophagus resulting in functional obstruction. The cause of the lesion is unknown although genetic and immunologic factors have been suggested. An association with serological HLA epitopes has been previously reported. In this study, we have further examined this HLA class II association with susceptibility to achalasia by DNA based methods. Achalasia patients ( n =40) and healthy controls ( n = 275), all Caucasians and unrelated, were included in the analysis. The strongest associations were with HLA-DQAl*0101 and two HLA-DQαβ heterodimers having their a chain encoded by this allele. Moreover, relative risk was significantly higher in DQAl*0101 homozygotes as compared to heterozygotes and results suggested that DQB1*02 may have a protective role. 相似文献
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HLA-DR expression is associated with excellent prognosis in squamous cell carcinoma of the larynx 总被引:5,自引:0,他引:5
F. Esteban F. Ruiz-Cabello A. Concha A. Pérez-Ayala J. A. Sánchez-Rozas F. Garrido 《Clinical & experimental metastasis》1990,8(4):319-328
We studied class I I antigen expression and tumor-infiltrating leukocytes (TIL) in tissue sections of 69 squamous cell carcinomas of the larynx and 24 lymph node metastases in the neck. HLA-DR expression was found only in eight well-differentiated, highly keratinizing squamous cell carcinomas comprising seven of the verrucous variety and one ventriculosaccular tumor. None of the metastases was positive for DR antigen. Neither primary tumors nor autologous metastases stained for DP or DQ antigens. DR-positive tumors shared a peculiar pattern of TIL composed mainly of T cells, most of which belonged to the cytotoxic/suppressor subset, and B cells. These neoplasms had in common a slow rate of growth, and are considered low-grade carcinomas in the literature. We conclude from our study that HLA-DR expression seems to characterize tumors with a prominent infiltrate and an excellent prognosis. 相似文献
25.
Phase I testing of a malaria vaccine composed of hepatitis B virus core particles expressing Plasmodium falciparum circumsporozoite epitopes
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Nardin EH Oliveira GA Calvo-Calle JM Wetzel K Maier C Birkett AJ Sarpotdar P Corado ML Thornton GB Schmidt A 《Infection and immunity》2004,72(11):6519-6527
We report the first phase I trial to assess the safety and immunogenicity of a malaria vaccine candidate, ICC-1132 (Malarivax), composed of a modified hepatitis B virus core protein (HBc) containing minimal epitopes of the Plasmodium falciparum circumsporozoite (CS) protein. When expressed in Escherichia coli, the recombinant ICC-1132 protein forms virus-like particles that were found to be highly immunogenic in preclinical studies of mice and monkeys. Twenty healthy adult volunteers received a 20- or a 50-microg dose of alum-adsorbed ICC-1132 administered intramuscularly at 0, 2, and 6 months. The majority of volunteers in the group receiving the 50-microg dose developed antibodies to CS repeats as well as to HBc. Malaria-specific T cells that secreted gamma interferon were also detected after a single immunization with ICC-1132-alum. These studies support ICC-1132 as a promising malaria vaccine candidate for further clinical testing using more-potent adjuvant formulations and confirm the potential of modified HBc virus-like particles as a delivery platform for vaccines against other human pathogens. 相似文献
26.
Oyarzo MP Lin P Glassman A Bueso-Ramos CE Luthra R Medeiros LJ 《American journal of clinical pathology》2004,122(3):348-358
We report 12 cases of t(6;9)(p23;q34)-positive acute myeloid leukemia (AML), all classified using the criteria of the World Health Organization classification. There were 10 women and 2 men with a median age of 51 years (range, 20-76 years). Dysplasia was present in all cases (9 previously untreated), and basophilia was present in 6 (50%). Immunophenotypic studies showed that the blasts were positive for CD9, CD13, CD33, CD38, CD117, and HLA-DR in all cases assessed. CD34 was positive in 11 (92%) of 12, and terminal deoxynucleotidyl transferase was positive in 7 (64%) of 11 cases. The t(6;9) was the only cytogenetic abnormality detected in 7 cases (58%), and 5 cases had additional chromosomal abnormalities. Of 8 cases assessed, 7 (88%) had flt3 gene mutations. We conclude that t(6;9)-positive AML cases have distinctive morphologic features, an immunophenotype suggesting origin from an early hematopoietic progenitor cell, and a high frequency of flt3 gene mutations. 相似文献
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28.
Mauricio R. M. P. Luz Fred van Leuven Tania C. Araújo-Jorge 《Parasitology research》1994,80(5):439-441
We analyzed the variations observed in the plasma levels of both alpha-macroglobulins (AM) and serum amyloid P (SAP) in mice from three different inbred strains (C3H, Balb/C and C57black/6) acutely infected withTrypanosoma cruzi. SAP levels increased in C57black/6 and Balb/C mice but not C3H mice. AM levels increased in all C3H mice but not in C57black/6 mice and rose slightly in only 43% of the Balb/C mice. AM and SAP levels are differently modulated in patterns that may be strain-determined. 相似文献
29.
Dulari S. Thilakarathne Carol A. Hartley Andrés Diaz-Méndez José A. Quinteros Omid Fakhri Mauricio J. C. Coppo 《Avian pathology》2020,49(4):369-379
ABSTRACT Latency is an important feature of infectious laryngotracheitis virus (ILTV) yet is poorly understood. This study aimed to compare latency characteristics of vaccine (SA2) and field (CL9) strains of ILTV, establish an in vitro reactivation system and examine ILTV infection in peripheral blood mononuclear cells (PBMC) in specific pathogen-free chickens. Birds were inoculated with SA2 or CL9 ILTV and then bled and culled at 21 or 35 days post-inoculation (dpi). Swabs (conjunctiva, palatine cleft, trachea) and trigeminal ganglia (TG) were examined for ILTV DNA using PCR. Half of the TG, trachea and PBMC were co-cultivated with cell monolayers to assess in vitro reactivation of ILTV infection. ILTV DNA was detected in the trachea of approximately 50% of ILTV‐inoculated birds at both timepoints. At 21?dpi, ILTV was detected in the TG only in 29% and 17% of CL9- and SA2-infected birds, respectively. At 35?dpi, ILTV was detected in the TG only in 30% and 10% of CL9- and SA2-infected birds, respectively. Tracheal organ co-cultures from 30% and 70% of CL9- and SA2-infected birds, respectively, were negative for ILTV DNA at cull but yielded quantifiable DNA within 6 days post-explant (dpe). TG co-cultivation from 30% and 40% of CL9-and SA2-infected birds, respectively, had detectable ILTV DNA within 6 dpe. Latency characteristics did not substantially vary based on the strain of virus inoculated or between sampling timepoints. These results advance our understanding of ILTV latency and reactivation. RESEARCH HIGHLIGHTS
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Following inoculation, latent ILTV infection was detected in a large proportion of chickens, irrespective of whether a field or vaccine strain was inoculated.
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In vitro reactivation of latent ILTV was readily detected in tracheal and trigeminal ganglia co-cultures using PCR.
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ILTV latency observed in SPF chickens at 21 days post-infection was not substantially different to 35 days post-infection.
30.
Edwards Lisa M. Le Huynh-Nhu Garnier-Villarreal Mauricio 《Maternal and child health journal》2021,25(4):554-564
Maternal and Child Health Journal - The purpose of this article was to describe the findings from a systematic review, quality review, and meta-analysis of risk factors for postpartum depression... 相似文献