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1.
Ticks Tick Borne Dis ; 13(6): 102053, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36279729

RESUMO

Ixodes ricinus ticks are considered as the vector of the Borrelia burgdorferi sensu lato complex in urban areas, including city parks and green recreational areas. The aim of the present study was to determine the prevalence of B. burgdorferi s. l. in urban areas in the city of Prague, Czech Republic. In selected public green areas in Prague, a total of 2819 I. ricinus ticks were collected in spring, from April to June, in 2014-2020. Quantitative real time PCR revealed 28.1% of ticks (31% of males, 33.7% of females and 25.8% of nymphs) to be positive for B. burgdorferi s. l. The prevalence varied significantly (p˂0.01) between collection sites, with the highest numbers of infected ticks found in the central city areas. The places serving people for recreational and sport activities in urban areas are characterized by a lower diversity of reservoir hosts, provide opportunity for exposure to Borrelia infected ticks, and pose a higher infection risk. We have detected seven Borrelia species in ticks: B. garinii, B. afzelii, B. bavariensis, B. burgdorferi sensu stricto, B. valaisiana, B. spielmanii, and B. finlandensis. Most positive ticks were infected by B. garinii (35%) and B. afzelii (36.9%). Our results show that the Borrelia transmission cycle occurs within urban biotops and highlight the need for surveillance of tick-borne pathogens in public green areas.

2.
Klin Onkol ; 35(3): 195-207, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35760572

RESUMO

BACKGROUND: A general characteristic of cancer metabolism is the skill to gain the essential nutrients from a relatively poor environment and use them effectively to maintain viability and create new bio-mass. The changes in intracellular and extracellular metabolites that accompany metabolic reprogramming associated with tumor growth subsequently affect gene expression, cell differentiation, and tumor microenvironment. During carcinogenesis, cancer cells face huge selection pressures that force them to constantly optimize dominant metabolic pathways and undergo major metabolic reorganizations. In general, greater flexibility of metabolic pathways increases the ability of tumor cells to satisfy their metabolic needs in a changing environment. PURPOSE: In this review, we discuss the metabolic properties of cancer cells and describe the tumor promoting effect of the transformed metabolism. We assume that changes in metabolism are significant enough to facilitate tumorigenesis and may provide interesting targets for cancer therapy.


Assuntos
Neoplasias , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Humanos , Redes e Vias Metabólicas , Neoplasias/metabolismo , Microambiente Tumoral
3.
Sci Rep ; 12(1): 7876, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35552438

RESUMO

The coexistence of species in a given community depends on the set of species involved and the timing of their interactions. Many native communities are increasingly forced to face both direct and indirect pressures from new alien predators, which, in extreme cases, can lead to the extinction of prey populations. In this study, we examine the dynamics of the ontogeny of common frog (Rana temporaria) tadpoles under different time patterns of an alien predator-the red-eared slider (Trachemys scripta elegans) presence. We found that the tadpoles had a longer larval period and were smaller in size at metamorphosis and lower in body mass when the predator was present in early development than when the tadpoles developed without a predator. The early presence of a predator conspicuously reduced the growth increments of the tadpoles at early development. After the removal of the predator, growth accelerated above the level measured under the conditions of both the late predator and no predator. However, these growth rates did not exceed the growth rates of equally sized tadpoles in the other treatments and therefore were not sufficient to compensate for the growth slowdown in the first part of development. The presence of a predator in late tadpole development influenced neither the time to metamorphosis nor size/body mass at metamorphosis. In conclusion, the predator had the effect on metamorphosis traits only if it was present in the early development of tadpoles.


Assuntos
Comportamento Predatório , Tartarugas , Animais , Anuros , Larva , Metamorfose Biológica , Rana temporaria
4.
Klin Onkol ; 32(2): 97-100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30995848

RESUMO

BACKGROUND: With advancements in diagnostic techniques, oligometastatic prostate cancer is diagnosed in patients who were, in the past, considered to have localized disease. Moreover, evidence of the effectiveness of treatment intensification for this disease is increasing, focusing on primary tumors as well as metastatic lesions. Thus, we can delay the start of systemic palliative treatment and improve overall survival. Many questions remain unclear, such as the definition of oligometastasis disease, or which patients should be offered aggressive treatment. Data are limited and come from small retrospective studies but show conclusively the benefits of survival in targeted primary prostate and metastatic prostate cancer therapy with surgery or radiotherapy. Often, stereotactic radiotherapy is used in this indication, with minimal side effects. In retrospective studies, 3-5 metastatic lesions were generally accepted for definition of oligometastatic disease, but patient subgroups were heterogeneous. A recent study attempts to better define oligometastatic disease and find out the right degree of intensification of treatment. When and in which patient to use metastasis-targeted therapy and when the standard systemic treatment is already meaningful. It is already clear that selected patients benefit from targeted personalized treatment. PURPOSE: The purpose of this review is to offer an update of the problem of oligometastatic prostate cancer. The article presents an overview of data from contemporary literature, modern possibilities of diagnostic imaging methods and treatment options of oligometastatic prostate cancer including surgery and radiotherapy.  authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 8. 2. 2019 Accepted: 5. 3. 2019.


Assuntos
Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Humanos , Masculino , Metástase Neoplásica , Prognóstico
5.
Klin Onkol ; 28(6): 416-25, 2015.
Artigo em Tcheco | MEDLINE | ID: mdl-26673991

RESUMO

The immune system is believed to play a dual role in carcinogenesis. On one hand, it could prompt tumorigenesis and cancer progression, on the other hand, it has the capacity to eradicate tumor cells. There has been an evidence of natural immunogenicity in breast cancer and we have also witnessed several attempts to stimulate non-specific antitumor immune response (Coleys toxin, BCG vaccine etc.). New technologies and further knowledge of molecular basis of immune system and its function encouraged the development of effective immunotherapy capable of inducing a solid antitumor activity. These agents appear promissing in the prevention and therapy of breast carcinoma as well. The assumption is based on the results of several antitumor vaccine trials targeted against HER2, MUC1, CEA and mammaglobin-A, as well as immune checkpoint inhibitors (e.g. CTLA-4, PD-1/ PD-L1, LAG3). With regards to different mech-anisms of action of these agents, their combination might bring about synergistic antitumor effects. Nonetheless, monoclonal antibodies and cytostatic agents already approved for breast cancer treatment might be exploited for their immunomodulation effect as well. This article addresses prospects for immunotherapy of breast carcinoma in detail.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/prevenção & controle , Imunoterapia/métodos , Feminino , Humanos
6.
Klin Onkol ; 28(6): 405-15, 2015.
Artigo em Tcheco | MEDLINE | ID: mdl-26673990

RESUMO

BACKGROUND: In the Czech Republic, around 6,500 women get breast cancer each year; out of this number, nearly 1,000 women are triple negative subtype. Triple negative breast cancer is characterized by lack of expression of α-estrogen, progesterone, and HER2 receptors. Vast majority of these cases are low-differentiated carcinomas, majority belonging to the basal-like subgroup defined originally by DNA chips. Clinically, they are characterized by greater aggressiveness, frequent rate of local recurrence and organ metastases. They are more common in younger women and are associated with the occurrence of hereditary forms of breast cancer caused by pathogenic mutations in the BRCA1 gene and in rare cases also BRCA2. AIM: The objective of this review is to provide comprehensive information about current knowledge of triple negative breast cancer. This paper summarizes information about epidemiology and etiopathogenesis of this disease, describes risk factors for both sporadic and hereditary forms of triple negative breast cancer, addresses histopathologic and molecular classification of triple negative breast cancer, and these characteristics associates with treatment and prediction of disease development. The article also addresses new anticancer drugs tested for triple negative breast cancer. CONCLUSION: Triple negative breast cancer is a heterogeneous group of diseases with limited therapeutic options. The key to further shift in therapy is detailed knowledge of its clinical and molecular diversity and identification of predictive biomarkers. Further improvement of therapy results of triple negative breast cancer cannot be expected before targeted therapy of this disease is found.


Assuntos
Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , República Tcheca/epidemiologia , Feminino , Humanos
7.
Klin Onkol ; 27(5): 340-6, 2014.
Artigo em Tcheco | MEDLINE | ID: mdl-25312711

RESUMO

Cyclin-dependent kinases (CDKs) participate in many cellular processes and play a crucial role in the regulation of cell cycle and transcription processes. Recently, CDK12 was identified as a key factor orchestrating transcription of genes, such as BRCA1, ATM, ATR, FANCI and FANCD2, which are involved in the DNA-damage response pathway. Importantly, inhibition of function of these genes commonly leads to induction of genomic instability followed by cancer development, but the precise contribution of CDK12 to these processes is to be unveiled. Nevertheless, several mutations affecting function of CDK12 were already identified in a variety of tumors of different origin (ovary, breast, prostate, intestine) making tumors sensitive to cytostatics promot-ing DNA damage (platin derivatives, alkylating regimens) and inhibitors of DNA repair (PARP inhibitors). Such an effect has been already observed in the model of high grade serous ovarian carcinomas. Thus, CDK12 is becoming a potential therapeutic target of drugs causing synthetic lethality in these cells. Our review summarizes most recent information about CDK12 function in cancer and discusses potential use of CDK12 in clinics.


Assuntos
Carcinogênese , Quinases Ciclina-Dependentes/fisiologia , Dano ao DNA , Reparo do DNA , Transcrição Gênica , Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Carcinogênese/genética , Instabilidade Cromossômica , Cisplatino/uso terapêutico , Quinases Ciclina-Dependentes/genética , Feminino , Humanos , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias Ovarianas/tratamento farmacológico
8.
Placenta ; 35(8): 655-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24889156

RESUMO

This study aimed to determine whether maternal cell contamination exists in cells derived from equine umbilical cord tissue, a perspective material for cell-based therapies in veterinary medicine. Potential maternal cell contamination was analyzed at DNA level via a set of 16 microsatellite markers in cells originating from the cord tissue of 22 foals. In these cells no maternal cell contamination was detected at a sensitivity level of 0.01%. Our results suggest that equine umbilical cord tissue-derived cells are entirely of fetal origin.


Assuntos
Células Cultivadas , Cavalos , Células-Tronco Mesenquimais , Cordão Umbilical/citologia , Animais , Feminino , Repetições de Microssatélites , Gravidez
9.
Klin Onkol ; 27(2): 97-102, 2014.
Artigo em Tcheco | MEDLINE | ID: mdl-24739045

RESUMO

CASE: Herein we report a case of a man with a B- cell non-Hodgkin lymfoma, primarily diagnosed by topographic and morfology tokens as lobular breast carcinoma and, as such, it was treated by chemotherapy and endocrine therapy. The treatment resulted in complete remission for 3,5 years. However, the subsequent relapses that arised in retrocrural and left axilary area did not respond adequately to breast cancer targeted chemotherapy. Therefore the patient underwent re-exstirpation of axillary lymph node yielding a surprising histology finding of folicular lymphoma. The primary biopsy specimen was histologicaly reevaluated and the initial dia-gnosis was reclassified as folicular lymphoma. The patient was given an adequate chemotherapy and targeted treatment that established a complete remission. Six months afterwards there was a relapse detected in the retrocrural area. The patient underwent palliative radiotherapy that brought about complete remission and, so far, he is in good condition. It has been eight years since the cancer dia-gnosis was established. This case report is appended by review of literature dealing with diagnostic confusion of these two malignancies. CONCLUSION: Re -biopsy plays a significant role in case of treatment strategy controversies, predominantly on condition of atypical course of malignant disease. It should always be considered in case of cancer relapse, especially if the phenotype specfication could affect the treatment decision.


Assuntos
Neoplasias da Mama Masculina/patologia , Carcinoma Lobular/patologia , Erros de Diagnóstico , Linfoma de Células B/patologia , Linfoma Folicular/patologia , Recidiva Local de Neoplasia/patologia , Biópsia , Humanos , Masculino
10.
Klin Onkol ; 25(3): 188-98, 2012.
Artigo em Tcheco | MEDLINE | ID: mdl-22724568

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) represents a heterogeneous group of breast cancers that do not express ER-α, PgR and Her-2 receptors. Generally, these tumors are aggressive and more common in younger women, in which an association of TNBC with mutations in the BRCA1 gene was documented. The aim of our study was to create a representative group of patients with TNBC, which could be analyzed and the data gathered to build basic epidemiological, molecular and clinical characteristics of Czech patients with TNBC. PATIENTS AND METHODS: We performed basic clinical-pathologic correlations in a group of 335 patients diagnosed and/or treated for TNBC at the Masaryk Memorial Cancer Institute between 2004 and 2009. We also performed immunohistochemical examination of expression of cytokeratin 5/6, cytokeratin 14 and EGFR to identify the basal-like subset of TNBC. RESULTS: The median age of patients with TNBC was 56 years, range 25-88 years. A total of 9.25% of TNBC cases were diagnosed in patients under the age of 34, and another 15.22% of cases were in the age group of 35 to 44 years. 'Basal-like' carcinomas accounted for 75% of TNBC. We confirmed the aggressive nature of this disease: in the follow-up period we observed a relapse in 25% of patients: 55% of deaths due to disease progression occured within 2 years after diagnosis of the disease. Treatment strategies include chemotherapy, in most cases (88.4%). Chemotherapy was mostly based on regimens with anthracyclines or in combination with taxanes. The most important negative prognostic factors in relation to OS (disease specific OS) were: higher clinical stage (p < 0.0001), pN - positive status (p < 0.0001), high proliferative activity (as measured by Ki-67, cut-off 50%, HR = 0.4740, p = 0.0411) and positive expression of CK5/6 (HR = 0.4274, p = 0.0338). In relation to DFS, the negative prognostic significance was found for these factors: higher clinical stage (p < 0.0001), pN positive status (p < 0.0001), high proliferative activity (Ki-67, cut-off 50%, HR = 0.04993, p = 0.0240). DFS was longer in patients with a higher number of applied cycles of anthracycline-based chemotherapy (> 4 cycles, HR = 1.7273, p = 0.0467). CONCLUSION: TNBC is an aggressive form of breast cancer, which may occur in patients of all ages, but more frequently in younger patients. Only early detection of disease and intensive treatment gives a high chance of cure. Unfortunately, no reliable predictive factors have been identified so far. Better therapeutic results can be expected from targeted therapy.


Assuntos
Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Feminino , Humanos , Queratinas/metabolismo , Pessoa de Meia-Idade , Taxa de Sobrevida
11.
Water Sci Technol ; 47(1): 29-32, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12578170

RESUMO

A magnetic separation device is being developed for removal of iron and heavy metals from water. The device consists of a column of supported magnetite surrounded by a movable permanent magnet. The mineral magnetite, or synthetically prepared iron ferrite (FeO x Fe2O3), is typically supported on various materials to permit adequate water passage through the column. In the presence of an external magnetic field, enhanced capacity was observed in using supported magnetite for removal of actinides and heavy metals from wastewater. The enhanced capacity is primarily due to magnetic filtration of colloidal and nanoscale particles along with some complex and ion exchange sorption mechanisms. This paper will review some previous work on the use of magnetite for wastewater treatment and discuss the development and potential of the magnetic nanoscale filtration/sorption process for water treatment. Recent research results are also presented on preliminary experimental studies using the process with water samples containing iron.


Assuntos
Ferro/isolamento & purificação , Magnetismo , Metais Pesados/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Adsorção , Coloides , Compostos Férricos/química , Filtração
12.
Environ Sci Technol ; 36(22): 4880-5, 2002 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-12487312

RESUMO

Sequential extractions of contaminants from a soil or sediment have been shown to be cost-effective contaminated site assessment tools that provide information on contaminant partitioning within an environmental matrix. Such information is necessary for defining remediation alternatives and mitigation strategies. The typical sequential extraction approach involves a batch method, and known limitations include the possibility of contaminant readsorption to the remaining soil or sediment In this work, a flow-through reactor was constructed and tested for application in a sequential extraction scheme. The sequential extraction scheme used was one developed for actinide-contaminated materials. The flow-through approach gave partitioning results that were similar to the batch method for uranium. We also monitored the extraction of stable Ca, K, Fe, Al, Zr, and Sc and obtained partitioning results generally similar to those observed with the batch extraction, except for Ca. Our results indicate readsorption of Ca when using a batch approach is small but significant and is eliminated with our new flow-through method. A limitation of the flow-through method is the possibility of underextraction of certain phases and higher analytical uncertainties. These uncertainties are more difficult to minimize, as compared to the uncertainty obtained with a batch approach.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes do Solo/análise , Técnicas de Química Analítica/métodos , Metais Pesados/análise , Reprodutibilidade dos Testes
13.
Bioorg Med Chem ; 9(8): 2061-71, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11504642

RESUMO

A series of 5-, 6-, 7- and 8-aza analogues of 3-aryl-4-hydroxyquinolin-2(1H)-one was synthesized and assayed as NMDA/glycine receptor antagonists. The in vitro potency of these antagonists was determined by displacement of the glycine site radioligand [(3)H]5,7-dicholorokynurenic acid ([(3)H]DCKA) in rat brain cortical membranes. Selected compounds were also tested for functional antagonism using electrophysiological assays in Xenopus oocytes expressing cloned NMDA receptor (NR) 1A/2C subunits. Among the 5-, 6-, 7-, and 8-aza-3-aryl-4-hydroxyquinoline-2(1H)-ones investigated, 5-aza-7-chloro-4-hydroxy-3-(3-phenoxyphenyl)quinolin-2-(1H)-one (13i) is the most potent antagonist, having an IC(50) value of 110 nM in [(3)H]DCKA binding and a K(b) of 11 nM in the electrophysiology assay. Compound 13i is also an active anticonvulsant when administered systemically in the mouse maximum electroshock-induced seizure test (ED(50)=2.3mg/kg, IP).


Assuntos
Quinolonas/síntese química , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Glicina/química , Glicina/metabolismo , Oócitos , Quinolonas/química , Quinolonas/farmacologia , Ensaio Radioligante , Ratos , Relação Estrutura-Atividade , Trítio , Xenopus
14.
Curr Rheumatol Rep ; 3(3): 191-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11352787

RESUMO

Cell death by apoptosis is an integral part of many biologic processes, including embryonic development, T- and B-cell selection, the elimination of potentially autoreactive lymphocytes in the periphery, and maintenance of lymphocyte homeostasis through activation-induced cell death. There is also increasing evidence that apoptosis may maintain immune tolerance and that it may be the process that generates the self antigens responsible for the initial development of autoimmunity. This review discusses some of the biochemical steps involved in the apoptotic process, how potentially immunogenic self antigens are generated during apoptosis, and the mechanisms by which the products of apoptosis are cleared and processed to avoid breaking immune tolerance.


Assuntos
Apoptose/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Animais , Apoptose/fisiologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Caspases/fisiologia , Via Clássica do Complemento/imunologia , Humanos , Tolerância Imunológica , Lúpus Eritematoso Sistêmico/fisiopatologia , Fosfotransferases/fisiologia , Transdução de Sinais , Receptor fas/fisiologia
15.
J Immunol ; 166(5): 3231-9, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11207277

RESUMO

Complement protein C1q is required to maintain immune tolerance. The molecular mechanism responsible for this link has not been determined. We have previously demonstrated that C1q binds directly and specifically to surface blebs of apoptotic human keratinocytes, suggesting that it may participate in clearance of self Ags generated during programmed cell death. Here, we demonstrate that C1q also binds directly to apoptotic blebs of vascular endothelial cells and PBMC. These apoptotic cells are recognized by the globular heads of C1q, which bind specifically to the surface blebs, and deposition increases as the blebs mature on the cell surface. These observations suggest that C1q may participate in the clearance of apoptotic cells from the circulation and from the walls of the vascular lumen. The interaction of surface blebs with the globular heads of C1q suggests that surface blebs may be capable of directly activating the classical pathway of complement under certain circumstances, generating C4- and C3-derived ligands for receptors such as CR1, CR2, CR3, and CR4. Appropriate recognition of apoptotic cells by C1q and targeted clearance of the molecular contents of surface blebs to complement receptors may be critical for the maintenance of immune tolerance.


Assuntos
Apoptose/imunologia , Complemento C1q/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Células Cultivadas , Complemento C1q/química , Via Clássica do Complemento , Endotélio Vascular/metabolismo , Endotélio Vascular/ultraestrutura , Técnica Indireta de Fluorescência para Anticorpo , Células HeLa , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/ultraestrutura , Microscopia Confocal , Microscopia de Fluorescência , Ligação Proteica/imunologia , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Propriedades de Superfície
16.
Curr Rheumatol Rep ; 2(1): 32-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11123037

RESUMO

Apoptosis may have a dual role in the pathogenesis of autoimmune diseases such as systemic lupus erythematosus. First, this process may be integral in the clonal deletion of self-reactive lymphocytes and maintenance of peripheral tolerance. Second, apoptosis generates altered self-antigens with the potential for breaking self-tolerance. This review will discuss these two aspects of apoptosis and autoimmunity, and explore the potential role of the classical complement pathway in this context.


Assuntos
Apoptose/imunologia , Autoimunidade/fisiologia , Via Clássica do Complemento/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Receptores de Complemento/deficiência , Feminino , Humanos , Imunidade Celular/fisiologia , Masculino , Sensibilidade e Especificidade
17.
Immunopharmacology ; 42(1-3): 47-52, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10408365

RESUMO

Complete deficiency of C1q, the first component of the classical pathway of complement activation, is almost invariably associated with the development of systemic lupus erythematosus. Understanding why complement deficiency results in the specific autoimmune phenotype of SLE may provide valuable clues to the role of complement in the maintenance of immune tolerance. The following review will focus on the characteristics of complement-deficient SLE and the experimental evidence in support of our hypothesis that C1q may critically influence the immune response to self-antigen contained within surface blebs generated by apoptotic cells.


Assuntos
Complemento C1q/deficiência , Via Clássica do Complemento/imunologia , Tolerância Imunológica , Lúpus Eritematoso Sistêmico/imunologia , Animais , Humanos , Lúpus Eritematoso Sistêmico/sangue
18.
J Immunol ; 157(9): 4028-36, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8892636

RESUMO

Dendritic cells are potent stimulators of Ag-specific T cell responses and have been implicated in the pathogenesis of HIV-1 and other viral infections. Although cytokines may be involved in both of these processes, there is little information on the expression of cytokines by human blood dendritic cells. We characterized cytokine gene and protein expression in dendritic cells that were purified from normal human PBMC by flow cytometry and stimulated in vitro for up to 24 h with HIV-1 or herpes simplex virus (HSV). The unstimulated, uncultured dendritic cells were defined by their phenotype (HLA DR+ CD3- CD19- CD16- CD56- CD14-) and distinct morphology, lack of mRNA expression for CD3, CD14 and CD19, and presence of mRNA for CD4 and CD83. The purified dendritic cells also expressed CD4 (70-90%), CD33 (36-48%), and CD11c (44-54%); lacked CD1a expression (<1%); and were potent stimulators of an allogeneic MLR. The stimulated dendritic cells expressed mRNA for IFN-alpha, IL-1alpha, IL-1beta, IL-6, IL-10, IL-12, GM-CSF, and TNF-alpha within 4 to 12 h as determined by reverse transcription-PCR, with higher levels induced by HSV compared with HIV-1 strains IIIb or BaL. In contrast, the dendritic cells produced detectable protein only for IFN-alpha and IL-6 in response to HIV-1 or HSV, and IL-1beta in response to HSV within 24 h. There were no differences in expression of CD80 and CD86 surface molecules by dendritic cells that were either mock stimulated or stimulated with HIV-1 or HSV for 24 h. Production of IFN-alpha, IL-1beta, and IL-6 by dendritic cells may be important to the immunologic function of these cells and their role in the pathogenesis of HIV-1 and HSV infections.


Assuntos
Células Sanguíneas/imunologia , Citocinas/biossíntese , Células Dendríticas/imunologia , HIV-1/imunologia , Simplexvirus/imunologia , Antígenos CD/análise , Antígenos CD/biossíntese , Antígenos CD/genética , Antígeno B7-1/biossíntese , Antígeno B7-1/genética , Antígeno B7-2 , Citocinas/genética , Regulação da Expressão Gênica , Humanos , Imunofenotipagem , Teste de Cultura Mista de Linfócitos , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
19.
Mol Reprod Dev ; 44(3): 332-42, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8858603

RESUMO

Mature Xenopus laevis spermatozoa are capable of binding plasmid pAPrC carrying the complete Rous sarcoma virus (RSV) DNA. Each sperm cell associates, on an average, with 70-160 molecules of the plasmid DNA in a DNase resistant form, if the spermatozoa were exposed to the DNA at a concentration of 1.0-1.4 micrograms/10(7) sperm cells. Fertilization with pAPrC-treated spermatozoa induced developmental malformations in 25-30% of embryos. Immunohistochemical analysis of tissue sections from defective animals revealed aberrations in myotomal structures, and increased expression of pp60src protein in myoblasts, neuronal tube, and epidermis. The presence of characteristic v-src and RSV-long terminal repeat (LTR) sequences in X. laevis DNA was detected by PCR analysis. Embryonic RNA hybridized with a src-specific and an RSV-LTR specific probes indicating expression of the viral DNA. Plasmid DNAs without the v-src gene (pATV9) or completely free of any RSV sequences (pBR322) did not induce any changes in embryonic development. Our results provide evidence that the pBR322-cloned DNA form of the RSV genome associates with frog sperm cells in a DNase-resistant manner suggesting internalization and may be subsequently carried into eggs during the process of artificial fertilization. Correlation between the defective morphogenesis of X. laevis and increased expression of the src gene as well as an interference of RSV DNA with the developmental programs of frog embryos are discussed.


Assuntos
Vírus do Sarcoma Aviário/genética , DNA Viral/metabolismo , Espermatozoides/metabolismo , Xenopus laevis/metabolismo , Animais , Fertilização , Técnica Indireta de Fluorescência para Anticorpo , Masculino , Óvulo , RNA Viral/análise , Xenopus laevis/embriologia
20.
Clin Diagn Lab Immunol ; 2(2): 138-42, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7697520

RESUMO

We previously reported that human immunodeficiency virus type 1 (HIV-1), herpes simplex virus (HSV), and Sendai virus induce higher levels of alpha interferon (IFN-alpha) in blood dendritic cells than in monocytes of healthy donors. In the present study, the levels of IFN-alpha induced by T-cell tropic (IIIb and RF) and monocytotropic (BaL) strains of HIV-1 and by HSV were significantly decreased in peripheral blood mononuclear cells (PBMCs) derived from subjects with asymptomatic and symptomatic HIV-1 infection. In contrast, Sendai virus, a paramyxovirus that induces proportionally more IFN-alpha in monocytes and B cells than do either HIV-1 or HSV, stimulated normal levels of IFN-alpha in PBMCs from the HIV-1-infected men. The IFN-alpha produced by PBMCs from the HIV-1-seropositive subjects was partially acid labile, whereas the IFN-alpha produced by PBMCs from the HIV-1-seronegative donors was acid stable. We hypothesize that there is a selective defect in IFN-alpha production by peripheral blood dendritic cells, whereas the host retains the IFN-alpha-producing capacity of monocytes and B lymphocytes. The loss of IFN-alpha production in response to HIV-1, herpesviruses, and possibly other pathogens could contribute to the progression of HIV-1 infection and to the development of AIDS.


Assuntos
Infecções por HIV/sangue , HIV-1 , Interferon-alfa/biossíntese , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Células Cultivadas , Estudos de Coortes , Infecções por HIV/microbiologia , Humanos , Interferon-alfa/sangue , Masculino , Vírus da Parainfluenza 1 Humana , Simplexvirus , Linfócitos T/imunologia , Linfócitos T/microbiologia
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