RESUMO
OBJECTIVE: Compared with incidental papillary thyroid microcarcinoma (microPTC), incidental medullary thyroid microcarcinoma (microMTC) is clinically more significant. The objective of the present study was to summarize our experience in detecting microMTCs. METHODS: From 1995 to 2011, there were 10825 thyroid fine needle aspirates (FNAs) guided using high-resolution ultrasound with on-site preparation and evaluation by a cytopathologist. Of the 140 microcarcinomas detected, 132 were microPTCs and eight were microMTCs, which are the subject of the present study. RESULTS: All eight cases were incidentalomas and none of the five women and three men, age 37-70 years, had a family history of MTC. One patient had two FNAs at an interval of 10 months, two had a single lymph node metastasis and one had a 0.1-cm tumour nodule near the main tumour. Four of five plasmacytoid cell microMCTs had irregular borders; two round cell and one rectangular cell tumours had smooth borders. In contrast, 17 larger MTCs diagnosed in the same period included seven plasmacytoid, four giant cell and six spindle cell types. All five plasmacytoid microMTCs were correctly diagnosed on FNA, but the round cell and rectangular cell tumours were undercalled as follicular lesions. Sampling of colloid from adjacent follicles was noted in microMTCs. Two were diagnosed on histology following recommended surgery and one was diagnosed on recommended repeat FNA. CONCLUSIONS: US-guided FNA of thyroid lesions is a powerful tool in the detection of microMTCs, provided that cytopathologists are alerted to the pitfalls described in the present study.
Assuntos
Biópsia por Agulha Fina , Neoplasias do Tronco Encefálico/diagnóstico , Carcinoma/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Adulto , Idoso , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/patologia , Carcinoma/diagnóstico por imagem , Carcinoma/patologia , Citodiagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , UltrassonografiaRESUMO
BACKGROUND: Inflammatory breast cancer (IBC) represents the most aggressive presentation of breast cancer. Women diagnosed with IBC typically have a poorer prognosis compared with those diagnosed with non-IBC tumors. Recommendations and guidelines published to date on the diagnosis, management, and follow-up of women with breast cancer have focused primarily on non-IBC tumors. Establishing a minimum standard for clinical diagnosis and treatment of IBC is needed. METHODS: Recognizing IBC to be a distinct entity, a group of international experts met in December 2008 at the First International Conference on Inflammatory Breast Cancer to develop guidelines for the management of IBC. RESULTS: The panel of leading IBC experts formed a consensus on the minimum requirements to accurately diagnose IBC, supported by pathological confirmation. In addition, the panel emphasized a multimodality approach of systemic chemotherapy, surgery, and radiation therapy. CONCLUSIONS: The goal of these guidelines, based on an expert consensus after careful review of published data, is to help the clinical diagnosis of this rare disease and to standardize management of IBC among treating physicians in both the academic and community settings.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Inflamatórias Mamárias/diagnóstico , Neoplasias Inflamatórias Mamárias/terapia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Técnicas e Procedimentos Diagnósticos , Feminino , Humanos , Terapia Neoadjuvante , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Radioterapia Adjuvante , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Tamoxifeno/uso terapêutico , TrastuzumabRESUMO
Fifty of 75 serum samples collected in the West Nile district of Uganda between August 1972 and July 1973 contained antibodies reactive with human T-cell leukemia (lymphotropic) virus type 3 (HTLV-III; mean titer, 601), while 12 of 75 samples were positive in a similar test for HTLV type 1 (HTLV-1) antibodies (mean titer, 236). The samples were screened by enzyme-linked immunosorbent assay and positive results were confirmed by a newly developed unlabeled antibody-peroxidase procedure with enhanced sensitivity for detection of antibody binding to immunoblots of HTLV-III antigen, demonstrating antibodies to proteins with molecular weights of 24,000, 41,000, and 76,000 in nearly all positive samples. Analysis of titration data indicated enhanced titers of antibody against HTLV-III and HTLV-I when coinfection occurred. The high prevalence and relatively low titers [compared to serum from patients with acquired immune deficiency syndrome (AIDS)] of antibodies recognizing HTLV-III proteins in sera from this population at a time that may predate or coincide with the appearance or spread of the AIDS agent (HTLV-III) suggest that the virus detected may have been a predecessor of HTLV-III or is HTLV-III itself but existing in a population acclimated to its presence. It further suggests an African origin of HTLV-III.
Assuntos
Infecções por Retroviridae/epidemiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/microbiologia , Criança , Deltaretrovirus/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/microbiologia , UgandaRESUMO
Antibodies specific for human T-cell leukemia-lymphoma virus type I (HTLV-I) were demonstrated in serum samples from various groups of people in South Africa, Uganda, Ghana, Nigeria, Tunisia, and Egypt. The samples had been collected for other purposes and were presumably selected without bias toward clinical conditions associated with HTLV infections. Regional differences in antibody positivity were observed, indicating widely distributed loci of occurrence of HTLV on the African continent in people of both black and white ancestry. Two patients with high titers of antibody to HTLV-I had some signs of adult T-cell leukemia-lymphoma. In several groups a high frequency of false positive serum reactions was indicated when specific confirmation steps were included in the assay. Further characterization of these sera revealed highly elevated immunoglobulin levels, possibly due to polyclonal activation of immunoglobulin synthesis in these subjects. The possibility that related cross-reactive human retroviruses coexist in the same groups was not eliminated.
Assuntos
Anticorpos Antivirais/análise , Deltaretrovirus/imunologia , Adulto , África , População Negra , Linfoma de Burkitt/imunologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Feminino , Humanos , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Retroviridae/imunologia , Linfócitos T , População BrancaRESUMO
Because of the many potent biological capabilities of the blood granulocytes, and their contact with platelets in various physiologic and pathologic states, a possible interaction between granulocytes and platelets was investigated. Platelets were purified by gel filtration and via a dialysis membrane were separated from suspensions of autologous granulocytes prepared by dextran sedimentation and resuspended in modified Tyrode's buffer. After 20 min at 37 degrees C platelet aggregation was shown to be diminished by such exposure, as compared to the aggregation of platelets incubated with dialysates of buffer only. When granulocytes were stimulated by the addition of 1.1-muM latex spheres as target particles for phagocytes, the dialysate of these cells exhibited greatly enhanced platelet-inhibitory properties. The addition of catalase to the platelets abolished the effect of exposing these cells to the dialysate of resting granulocytes and markedly inhibited the effect of exposing the platelets to the dialysate of phagocytosing granulocytes. Catalase treated with 3-amino-1,2,4-triazole had no platelet-protective capacity. Purified suspensions of lymphocytes released no platelet-inhibitory principle under these experimental conditions. Hydrogen peroxide in the dialysate of granulocytes was measured directly with an assay involving an H2O2-induced decrease in the fluorescence of scopoletin catalyzed by horseradish peroxidase. The dialysate of phagocytosing granulocytes contained 0.86 +/- 0.55 nmol H2O2/2.5 X 10(7) granulocytes when sampled at 20 min. By an alternate measurement technique in which scopoletin and horseradish peroxidase were present in the dialysate from time zero, the mean amount of H2O2 in the dialysate reached 4.0 +/- 1.3 nmol/2.5 x 10(7) granulocytes at 20 min. This discrepancy suggested the consumption of H2O2, possibly mediated by the granulocytes themselves. This possibility was investigated by the addition of exogenous H2O2 to the test system. Both granulocytes and platelets enhanced the disappearance of H2O2 from the dialysate, and the amount consumed was proportional to the amount of H2O2 added to the system. Glucose oxidase at 12 M U/ml plus glucose in excess resulted in the production of H2O2 at a rate and final amount comparable to that produced by phagocytosing granulocytes. This mixture, when substituted for phagocytosing granulocytes in the standard dialysis membrane experiment, induced an inhibition of platelet aggregation similar to that caused by the granulocytes. The observation that the release of H2O2 by the blood granulocyte influences platelet function suggests a potential role for the granulocyte in the regulation of hemostasis or thrombosis.
Assuntos
Plaquetas/fisiologia , Granulócitos/metabolismo , Peróxido de Hidrogênio/metabolismo , Leucócitos/metabolismo , Difosfato de Adenosina/farmacologia , Plaquetas/efeitos dos fármacos , Catalase/farmacologia , Depressão Química , Humanos , Linfócitos/metabolismo , Fagocitose , Agregação Plaquetária/efeitos dos fármacosRESUMO
The current status of inflammatory breast cancer (IBC) among U.S. females was reviewed with the use of data abstracted from medical records of patients diagnosed with breast cancer between 1975 and 1981 in nine geographic areas covered by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. Patients were selected on the basis of reported clinical and pathologic features of IBC and were divided into 3 groups: I) both clinical and pathologic features of IBC; II) clinical features without pathologic confirmation; and III) pathologic evidence only. The age distribution of pathologically defined IBC, in general, showed younger ages than those for other breast cancers in both the white and black populations. Further analysis was restricted to white females due to the relatively small numbers of black and other nonwhite patients with IBC. The disease presentations of both clinically and pathologically defined IBC were similar with regard to the likelihood of the presence of metastases at initial staging. Survival was evaluated by comparison of patients with nonmetastatic (MO) disease. Three years after diagnosis, the relative survival rates among patients in groups I, II, and III were observed to be 34, 60, and 52%, respectively. Survival of patients with all other types of breast cancer was 90% at 3 years. The management of IBC appeared to differ from the treatment of other forms of breast cancer; chemotherapy was given more frequently as the first course of cancer-directed therapy in white SEER females with evidence of MO IBC compared with the group with MO non-IBC. When all possible combinations of initial therapy were considered, the treatment for IBC was more variable than the treatment for non-IBC.
Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma/epidemiologia , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Carcinoma/tratamento farmacológico , Carcinoma/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estados UnidosRESUMO
Of 117 patients in remission for at least 12 months after chemotherapy for confirmed Burkitt's lymphoma, 14 subsequently relapsed. Frequency of ever relapsing in this group varied from 12% 2 years after chemotherapy to 3-8% 3-6 years after chemotherapy. Risk of very late relapse (VLR) increased with the occurrence of meningeal disease and/or relapse before a remission of 12 months or more was achieved. The use of combination chemotherapy and especially prophylactic intrathecal methotrexate significantly lowered the risk of VLR (P less than 0.03). Serial testing for antibodies to Epstein-Barr viral capsid antigen to the diffuse and restricted components of the early antigen complex and to the Epstein-Barr virus-specific nuclear antigen revealed minor fluctuations but no consistent increases in antibody titers preceding detection of VLR. The serologic follow-up tests thus were not clinically useful for prediction of the imminence of a recurrence. Patients developing VLR generally maintained moderate-to-high titers of antibodies to restricted or diffuse components throughout the long remission periods, which indicated that they were not beyond the danger of a relapse at an unspecified time in the future.
Assuntos
Anticorpos Antivirais/análise , Linfoma de Burkitt/diagnóstico , Herpesvirus Humano 4/imunologia , Adolescente , Adulto , Antígenos Virais/análise , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/terapia , Criança , Ciclofosfamida/uso terapêutico , Feminino , Humanos , Masculino , Neoplasias Meníngeas/secundário , Recidiva , Fatores de TempoRESUMO
Epstein-Barr virus (EBV) DNA (17.7 genome equivalents/cell) was found in tumor tissue from an American patient with Burkitt's lymphoma who had never traveled outside the United States. A lymphoid cell line (NAB) containing the EBV genome was established from tumor tissue from this patient; characteristics of this cell line were described. Previous Burkitt's tumors found in Americans and examined by molecular hybridization were negative for EBV DNA. Our results suggested that EBV is associated with at least some American Burkitt's tumors.
Assuntos
Linfoma de Burkitt/microbiologia , DNA Viral/isolamento & purificação , Herpesvirus Humano 4 , Adolescente , Antígenos Virais/análise , Linfoma de Burkitt/genética , Linfoma de Burkitt/imunologia , Cromossomos , Proteínas do Sistema Complemento , Feminino , Antígenos HLA , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina M , Receptores de Antígenos de Linfócitos BRESUMO
Several cerebrospinal fluid markers were found to be elevated in Burkitt's lymphoma patients with central nervous system (CNS) involvement. Antibody levels to the virus capsid antigen of the Epstein-Barr virus and to the brain cell antigens myelin and cerebroside were elevated during active CNS disease. Immune complexes were present in levels above 100 micrograms/ml in most patients with CNS involvement but tended to be low or negative in patients without CNS disease. Oligoclonal IgG bands were present in 12 of 13 patients with CNS disease and in only 3 of 26 patients with no clinical evidence of disease. None of these markers were present in 6 other tumor patients without CNS disease. The presence of these markers in 12 of 13 patients in whom CNS disease was involved suggests that these markers may be useful in determining the status of the tumor with regard to involvement of the CNS.
Assuntos
Linfoma de Burkitt/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso/secundário , Anticorpos/análise , Complexo Antígeno-Anticorpo/análise , Antígenos Virais/análise , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/patologia , Capsídeo/imunologia , Cerebrosídeos/imunologia , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina G/análise , Proteínas da Mielina/imunologia , Neoplasias do Sistema Nervoso/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso/imunologiaRESUMO
It is demonstrated in this study that a serum factor, a lymphocyte stimulation inhibitor (LSI), which inhibits Epstein-Barr virus (EBV)-induced lymphocyte stimulation, is a potentially useful tool in the diagnosis and monitoring of nasopharyngeal carcinoma (NPC). In a study of 25 patients with undifferentiated NPC, 20 healthy controls, and 20 patients with other head and neck tumors, LSI was found only in the NPC patients with active disease. In a more complete study of 8 patients longitudinally followed up for at least 20 months, a comparison of LSI with antibodies to a variety of EBV antigens including viral capsid antigen, early antigen, and nuclear antigen indicated that LSI levels provided a reliable and sensitive indicator of disease activity that should be added to clinical markers currently in use as monitors of disease activity in NPC.
Assuntos
Herpesvirus Humano 4/imunologia , Ativação Linfocitária , Linfócitos/imunologia , Neoplasias Nasofaríngeas/diagnóstico , Adulto , Idoso , Anticorpos Antivirais/análise , Antígenos Virais , Diagnóstico Diferencial , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/imunologia , Valores de ReferênciaRESUMO
The in vitro sensitivity of oncogenic herpesviruses, Epstein-Barr virus (EBV), and Herpesvirus saimiri (HVS) to human interferon produced by normal human leukocytes (Le), lymphoblastoid cell lines (LYI), and diploid fibroblasts (Fi) was studied. Four virus strains were used: HVS S295C, the highly oncogenic HVS S396-O, the transforming B95-8 strain of EBV, and the nontransforming P3HR1 strain of EBV. All interferons were active when applied to the cells after absorption of HVS and P3HR1-EBV, although different amounts were required to achieve 50% inhibition of HVS-induced cytopathic effect or EBV-induced early antigen (EA) expression. Transformation of human umbilical cord blood lymphocytes (HCBL) by the B95-8 strain of EBV was prevented only by Le and LYI. In these experiments, the most effective inhibitor of the oncogenic herpesviruses was Le, and the least effective was Fi. The effect of polynucleotides poly(I).poly(C) and the complex of poly(I).poly(C) with poly-L-lysine and carboxymethylcellulose on HVS and EBV was also studied. Their inhibitory action was proportionate to the ability of herpesvirus-infected cells to produce interferon. Thus owl monkey kidney cells, which produce relatively high levels of interferon, required nanogram quantities of polynucleotides to become resistant to HVS. Transformation of HCBL by B95-8-EBV was also prevented by poly(I).poly(C). In Raji cells superinfected with P3HR1-EBV, polynucleotides failed to stimulate interferon, and higher EBV-induced EA expression was observed. The percentage of P3HR1 and Raji cells spontaneously expressing EBV-associated antigens remained unchanged after exposure to either interferon or polynucleotides.
Assuntos
Herpesvirus Saimiriíneo 2/efeitos dos fármacos , Herpesvirus Humano 4/efeitos dos fármacos , Indutores de Interferon/farmacologia , Interferons/farmacologia , Animais , Aotus trivirgatus , Linhagem Celular , Transformação Celular Viral , Genes Virais/efeitos dos fármacos , Herpesvirus Humano 4/genética , Rim , Linfócitos/efeitos dos fármacos , Polinucleotídeos/farmacologiaRESUMO
Archival tissues, particularly formalin-fixed paraffin-embedded tumors, have become increasingly valuable in studies of the etiology of cancer. In non-Hodgkin's lymphoma, subclassification of tumors by immunophenotyping and identification of oncogenic viruses has allowed more accurate interpretation of associated epidemiological information. One such example is adult T-cell leukemia/lymphoma, which is not a single histopathological entity and usually is associated with human T-cell lymphotropic virus, type I. In addition to confirming the diagnosis, the pattern of virus distribution, utilized recently in studies of Epstein-Barr virus and human herpesvirus-6-associated lymphoma, has suggested which tumors are more likely to have the virus playing a passenger role (virus detected in uninvolved tissues) and in which tumors the virus may have an etiological role (virus restricted to tumor cells). Preservation and cataloguing of tumors and relevant clinical and demographic data may play an increasingly important role in demographic studies.
Assuntos
Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/patologia , Bancos de Tecidos , Humanos , Linfoma não Hodgkin/classificaçãoRESUMO
The relationship between natural cell-mediated cytotoxicity (NCMC) and antibody-dependent cell-mediated cytotoxicity (ADCC) was examined in an Epstein-Barr virus-infected target cell system. The total ADCC reactivity to Epstein-Barr virus-infected target cells varied considerably with different effector cells, indicating contributions to specificity by the effector cells as well as by antibodies in the sera. To investigate the role of each reactant, the effector cells, sera, and target cells were tested according to a three-dimensional experimental design and examined for selectivity with the two- and three-way interaction analysis. The two-way analysis was applied to different planes from the experiment to examine special interactions involving two of the three reactants. Selective ADCC was examined through the results from sera versus target cells, selective NCMC was examined by effector cells versus target cells, and the relationship between NCMC and ADCC was examined through the final plane of effector cells versus sera. A three-way interaction analysis applied to the same results supported the conclusions from the two-way analysis and allowed further inquiry into the concurrent role of three reactants. The design and analysis used in the study allowed detection of selective ADCC and NCMC for Epstein-Barr virus-infected target cells and variations in the efficiency of ADCC by different effector cells and in the modulation of NCMC by different sera.
Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Citotoxicidade Imunológica , Herpesvirus Humano 4/imunologia , Células Cultivadas , HumanosRESUMO
The relationship between immunoglobulin allotypes and risk of developing nasopharyngeal carcinoma was examined in a comparative study of 50 Chinese cases and 140 Chinese controls and 50 Malay cases and 79 Malay controls residing in Malaysia. Although the most common Gm phenotype was elevated in both Chinese and Malay nasopharyngeal carcinoma patients compared to their controls, there were no significant differences between cases and controls in the distribution of Gm haplotypes in either population. There were no differences between cases and controls in the distribution of Km alleles in either population. Thus a previously reported association of Km(1) with increased nasopharyngeal carcinoma risk in Tunisia is not confirmed in two Mongoloid populations in Malaysia.
Assuntos
Epitopos/genética , Haplótipos/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias gama de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/genética , Neoplasias Nasofaríngeas/imunologia , China/etnologia , Suscetibilidade a Doenças/imunologia , Epitopos/imunologia , Frequência do Gene , Predisposição Genética para Doença , Haplótipos/imunologia , Humanos , Cadeias gama de Imunoglobulina/imunologia , Cadeias kappa de Imunoglobulina/imunologia , Malásia/etnologia , Neoplasias Nasofaríngeas/etnologia , FenótipoRESUMO
Of 75 sera collected in the West Nile district of Uganda over a 1-year period between 1972 and 1973, 50 (66%) had antibody reactivity to human T-cell lymphotropic virus subgroup III (HTLV-III) at low titer levels. Sera were initially screened by HTLV-III enzyme linked immunosorbent assay and sera with values less than normal mean + 2 SD were removed from testing. The remaining sera were tested for positivity by an amplified Western blotting procedure which incorporated a three-layer immunoperoxidase procedure. Immunoglobulin reactive with HTLV-III Mr 24,000, 41,000, and 76,000 proteins were present in nearly all positive sera. The antibody status of this group was unlike any normal or acquired immunodeficiency syndrome-risk group previously tested. The high prevalence and relatively low titers suggest the detection as early as 1972 of a relative or predecessor of HTLV-III or of HTLV-III itself but existing in a population acclimated to its presence. It further suggests a likely African origin of HTLV-III.
PIP: Sera from 75 children from an isolated subsistence farming region of the Ugandan Nile valley in 1972-1973 showed a unique pattern of antibody titer to HTLV-III: a high prevalence but low titer for a limited number of viral proteins. The sera were originally collected at random as controls for a study of Burkitt's lymphoma. Mean age was 6.4 years. Sera were tested quantitatively by ELISA and 50 of 55 positives were confirmed by Western blot. The most prominent bands had molecular weights of 76,000, 41,000 and 24,000, coinciding with HTLV-III antigens previously described. The geometric mean titer was 295 with a range of 100-1000. The results suggest high prevalence of a closely related virus in this population.
Assuntos
Síndrome da Imunodeficiência Adquirida/microbiologia , Anticorpos Antivirais/análise , Antígenos Virais/imunologia , Deltaretrovirus/imunologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/etiologia , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Anticorpos Anti-HIV , Humanos , Técnicas Imunoenzimáticas , Masculino , Infecções por Retroviridae , Uganda , Proteínas Virais/imunologiaRESUMO
A population-based case control study of intermediate- and high-grade lymphoma in the County of Los Angeles, CA, was initiated in 1989. Human immunodeficiency virus (HIV)-positive lymphoma patients are compared to HIV-negative lymphoma patients, to HIV-positive controls with acquired immunodeficiency syndrome but without lymphoma, and to HIV-positive asymptomatic individuals. The HIV-negative lymphoma cases are compared to neighborhood controls, who are matched in terms of age, sex, race/ethnicity, and socioeconomic status. All cases are reviewed for pathology by a single group of pathologists. All cases and controls are studied for HIV, Epstein-Barr virus (EBV), and human herpesvirus 6 antigens and antibodies. Tissues from HIV-positive and -negative cases are studied for immunoglobulin gene rearrangement, presence of EBV and HIV, c-myc oncogene rearrangements, and karyotypic analysis. To date, with 294 lymphoma cases and 181 control cases interviewed, high-grade lymphoma has been diagnosed in 82% of the HIV-positive cases versus 40% of the HIV-negative cases (P = 0.001). Although elevated titers of EBV-viral capsid antigen were demonstrated in 82% of HIV-positive versus 50% of HIV-negative lymphoma cases, the geometric mean titer of EBV-viral capsid antigen is similar among HIV-positive lymphoma cases and HIV-positive controls. The geometric mean titer of human herpesvirus 6 antibodies was similar in HIV-positive and HIV-negative lymphoma cases and in the control populations. Monoclonality was demonstrated in all cases of lymphoma. EBV genome was demonstrated within lymphoma DNA in 68% of HIV-positive and 15% of HIV-negative lymphoma cases. Further study will be required to elucidate the full mechanisms of pathogenesis of the acquired immunodeficiency syndrome-related lymphomas.
Assuntos
Linfoma Relacionado a AIDS/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Rearranjo Gênico , Soropositividade para HIV/epidemiologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 6 , Humanos , Los Angeles/epidemiologia , Linfoma Relacionado a AIDS/microbiologia , Linfoma Relacionado a AIDS/patologia , Linfoma de Células B/epidemiologia , Linfoma de Células B/microbiologia , Linfoma de Células B/patologia , Linfoma não Hodgkin/epidemiologia , Linfoma não Hodgkin/microbiologia , Linfoma não Hodgkin/patologia , Pessoa de Meia-IdadeRESUMO
Chronic fatigue syndrome, an illness that frequently is associated with abnormalities of cellular immunity, has been reported anecdotally to be associated with an increased incidence of lymphoid hyperplasia and malignancy. This report describes an initial analysis of population-based cancer incidence data in Nevada, focusing on the patterns of non-Hodgkin's lymphoma prior to and subsequent to well described, documented outbreaks of chronic fatigue syndrome during 1984-1986. In a study of time trends in four age groups, the observed time trends were consistent with the national trends reported in the Surveillance, Epidemiology, and End Results Program. No statistically significant increase attributable to the chronic fatigue syndrome outbreak was identified at the state level. Additional studies are in progress analyzing the data at the country level, reviewing patterns in other malignancies, and continuing to monitor the cancer patterns over subsequent years.
Assuntos
Síndrome de Fadiga Crônica/complicações , Linfoma não Hodgkin/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Síndrome de Fadiga Crônica/epidemiologia , Humanos , Incidência , Linfoma não Hodgkin/epidemiologia , Pessoa de Meia-Idade , Nevada/epidemiologiaRESUMO
The mitochondrial genome of Neurospora is usually found in a single covalently closed circular 62-kbp DNA molecule. We report here that the mitochondrial genome of a phenotypic revertant of a stopper mutant (stp-ruv) is contained primarily in two separate, nonoverlapping, autonomously replicating circular chromosomes. The circles, one about 21 kbp and the other somewhat less than 36 kbp are derived from the most frequent classes of recombinant chromosomes (21 and 41 kbp) in the chromosomal population of mitochondria in the original stopper mutant. The new, more stable chromosomal configuration, is associated with the deletion of two sequences (1 kbp and 4 kbp) at the splice junctions of the two circles. The data suggest that both deletions are likely to have originated from a single recombinational event involved in generating the 36-kbp circle. Secondary, spontaneously arising derivatives of stp-ruv have been found to yield, at high copy number, short sections of the 21-kbp circle in covalently closed supercoiled circles varying from unit length to very high multimers. The amplified segments span a common segment likely to contain the replication origin of the 21-kbp chromosome.
Assuntos
Deleção Cromossômica , DNA Mitocondrial/genética , Neurospora crassa/genética , Neurospora/genética , Mutação , Hibridização de Ácido Nucleico , Mapeamento por RestriçãoRESUMO
The 21-kbp mitochondrial chromosome of the stp-ruv strain of Neurospora crassa undergoes regional amplification yielding plasmid-like supercoiled circles varying in size from subunit length to very high multimers. A comparison of the base sequence of the five plasmids studied, with the region of the chromosome from which they were derived, indicated that the amplified chromosomal segments were determined by a recombination-excision process near or within two structurally distinctive regions. One of these, consisting of nearly uninterrupted strings of Cs and Gs straddling tandem PstI site direct repeats, could form an extended hairpin loop with only a few mismatches. It was found at or near the 5' exchange point of all of the plasmids. An extended 35-bp sequence containing 17-bp direct repeats was the primary 3' site of exchange. Base sequence changes were found in the vicinity of exchange points. Most notable of these was a G insertion and T to C transition within a section of the 5' region likely to form a hairpin loop, suggesting the involvement of a mismatch repair-like mechanism in the recombination process. The sequence, TATATAGACATATA, was identified as a likely candidate for the site of replication initiation. A nearly identical sequence was found common to all of the corresponding plasmids of Podospora anserina and was reported near the presumed replication origin of the Drosophila yakuba mitochondrial chromosome. A search of GenBank revealed a remarkable association of the consensus sequence, TATATAGAXATATA, with the plus strand of organelle DNA.
Assuntos
Replicação do DNA , DNA Fúngico , DNA Mitocondrial/genética , Neurospora crassa/genética , Neurospora/genética , Plasmídeos , Recombinação Genética , Sequência de Bases , Dados de Sequência Molecular , Hibridização de Ácido NucleicoRESUMO
Human herpesvirus-6 (HHV-6), a ubiquitous virus that causes exanthem subitum and occasional cases of infectious mononucleosis, hepatitis and other viral syndromes, has also been associated with acute lymphocytic leukemia (ALL) in children. To further investigate this association, we obtained sera from 50 patients with ALL and 50 age-sex matched controls. Antibodies to HHV-6 were determined using ELISA and indirect immunofluorescent antibody (IFA) tests. No significant difference between antibody titers in the cases and controls was observed. Since seroepidemiologic studies have demonstrated higher HHV-6 antibody titers in young children than in adults, this serologic study suggests that the previous association reported for HHV-6 and ALL was a result of the age of the population rather than a relationship between the virus and the disease.