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1.
Clin Immunol ; 180: 128-135, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28506921

RESUMO

The etiology of multiple sclerosis (MS) remains elusive. Among the possible causes, the increase of anti-Neu5Gc antibodies during EBV primo-infection of Infectious mononucleosis (IMN) may damage the integrity of the blood-brain barrier facilitating the transfer of EBV-infected B cells and anti-EBV T cell clones in the brain. We investigated the change in titers of anti-Neu5Gc and anti-α1,3 Galactose antibodies in 49 IMN, in 76 MS, and 73 clinically isolated syndrome (CIS) patients, as well as age/gender-matched healthy individuals. Anti-Gal and anti-Neu5Gc are significantly increased during IMN (p=0.02 and p<1.10-4 respectively), but not in acute CMV primo-infection. We show that, whereas there was no change in anti-Neu5Gc in MS/CIS, the two populations exhibit a significant decrease in anti-Gal (combined p=2.7.10-3), in contrast with patients with non-MS/CIS central nervous system pathologies. Since anti-Gal result from an immunization against α1,3 Gal, lacking in humans but produced in the gut, our data suggest that CIS and MS patients have an altered microbiota or an altered response to this microbiotic epitope.


Assuntos
Doenças Desmielinizantes/sangue , Doenças Desmielinizantes/imunologia , Galactose/imunologia , Imunoglobulina G/sangue , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
2.
Environ Sci Technol ; 47(2): 750-6, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23237387

RESUMO

Silicate glasses are used as containment matrices for deep geological disposal of nuclear waste arising from spent fuel reprocessing. Understanding the dissolution mechanisms of glasses in contact with iron, an element present in large amounts in the immediate environment (overpack, claystone, etc.) would be a major breakthrough toward predicting radionuclide release in the geosphere after disposal. Two different reacted glass-iron interfaces-a short-term nuclear system and a long-term archeological system-were examined using a multiscale and multianalytical approach including, for the first time on samples of this type, STXM under synchrotron radiation. Comparisons revealed remarkable similarities between the two systems and shed light on Fe-Si interactions, including migration of iron within a porous gel layer and precipitation of Fe-silicates that locally increase short-term glass alteration and are sustainable over the long-term.


Assuntos
Vidro/química , Ferro/química , Silicatos/química , Porosidade , Resíduos Radioativos/análise , Solubilidade
3.
Sci Rep ; 12(1): 18948, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347969

RESUMO

For many patients with hematological malignancies such as acute leukemia or myelodysplastic syndrome allogeneic hematopoietic stem cell transplantation (allogeneic HSCT) is the only curative treatment option. Despite the curative potential of this treatment many patients experience relapse of their underlying disease or die due to multiple complications e.g. infections. Risk scores could help to assess the individual prognosis and guide patients and treating physicians to choose between different treatment options. Parameters reflecting the inflammatory status, such as neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR), have been demonstrated to be associated with prognosis and treatment complications in patients with various cancers. In this study, we evaluate pre-HSCT NLR, MLR and PLR as predictive markers in patients undergoing allogeneic HSCT. We demonstrate that a high (> 133) PLR level is associated with better clinical outcome. Patients with high pre-HSCT PLR show a significant better overall survival (p = 0.001), less relapses (p = 0.016), lower non-relapse-mortality (p = 0.022), less transfusions of red blood cells, platelets and fresh frozen plasma (p = 0.000), fewer episodes of fever (p = 0.002), considerably less different antibiotics (p = 0.005), fewer intensive care unit treatment (p = 0.017) and a lower in-hospital mortality (p = 0.024). Pre-HSCT PLR is easy to calculate by daily routine and could help to predict patient outcome after allogeneic HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfócitos , Humanos , Estudos Retrospectivos , Linfócitos/patologia , Plaquetas/patologia , Neutrófilos/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Prognóstico
4.
Clin Nutr ; 40(4): 1571-1577, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33744601

RESUMO

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (alloHSCT) is frequently associated with impaired oral intake and malnutrition, which potentially increases morbidity and mortality. Therefore, nutrition is one of the major challenges in the post-transplant period. METHODS: To document the current clinical approach in nutritional treatment, we designed a questionnaire concerning the current practice in nutrition after alloHSCT and distributed it to German speaking centers performing alloHSCT in Germany, Austria and Switzerland between November 2018 and March 2020. Twenty-eight (39%) of 72 contacted centers completed the survey, 23 from Germany, two from Austria and three from Switzerland, representing 50% of alloHSCT activity within the participating countries in 2018. RESULTS: All centers reported having nutritional guidelines for patients undergoing alloHSCT, whereby 86% (n = 24) provided a low-microbial diet during the neutropenic phase. The criteria to start parenteral nutrition (PN) directly after alloHSCT seemed to be consistent, 75% (n = 21) of the corresponding centers started PN if the oral nutritional intake or the bodyweight dropped below a certain limit. In the setting of intestinal graft-versus-host disease (GvHD) the current practice appeared to be more heterogenous. About 64% (n = 18) of the centers followed a special diet, added food stepwise modulated by GvHD symptoms, while only four centers regularly stopped oral intake completely (intestinal GvHD grade >1). Half of the centers (54%, n = 15) applied a lactose-free diet, followed by 43% (n = 12) which provided fat- and 18% (n = 5) gluten-free food in patients with intestinal GvHD. Supplementation of micronutrients in acute intestinal GvHD patients was performed by 54% (n = 15) of the centers, whereas vitamin D (89%, n = 25) and vitamin B12 (68%, n = 19) was added regularly independently of the presence of GvHD. Only 5 (18%) participating centers ever observed a food-associated infection during hospitalization, whereas food-associated infections were reported to occur more often in the outpatient setting (64%, n = 18). CONCLUSION: The survey documented a general consensus about the need for nutritional guidelines for patients undergoing alloHSCT. However, the nutritional treatment in clinical practice (i.e. lactose-, gluten- or fat-free in intestinal GvHD) as well as the use of food supplements was very heterogeneous. In line with current general recommendations the centers seemed to focus on safe food handling practice rather than providing a strict neutropenic diet. More high-quality data are required to provide evidence-based nutrition to patients during and after alloHSCT.


Assuntos
Dieta/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Desnutrição/prevenção & controle , Neutropenia/dietoterapia , Política Nutricional , Áustria , Peso Corporal , Consenso , Dieta/normas , Suplementos Nutricionais , Ingestão de Alimentos , Alemanha , Pesquisas sobre Atenção à Saúde , Humanos , Desnutrição/etiologia , Neutropenia/etiologia , Nutrição Parenteral/normas , Padrões de Prática Médica , Suíça
5.
AIDS ; 7(5): 665-8, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8391272

RESUMO

OBJECTIVE: To describe and evaluate a polymerase chain reaction (PCR) method for early diagnosis and prompt management of cytomegalovirus (CMV) retinitis in HIV-infected patients. METHODS: A total of 110 HIV-infected patients (Centers for Disease Control and Prevention stages II to IV) were sampled sequentially for isolation of CMV from peripheral blood leukocytes (PBL; n = 560) and for amplification of CMV DNA in PBL. Semiquantitative analysis of the PCR product was performed and each PCR-positive specimen was assigned a score between 1+ and 4+ (corresponding to four points on a standard curve of dilutions: 80, 800, 8000 and 80,000 CMV genome copies). RESULTS: Levels of CMV DNA in blood increased with HIV infection stage. We focused on eight patients who developed one or more episodes of retinitis during longitudinal follow-up, in whom we found a strong correlation between viraemia, high PCR signal (3+ or 4+) (P < 0.0001) and clinical symptoms. Relapse was preceded by an increase in CMV DNA and resolution correlated with clearance of CMV DNA from blood. CONCLUSIONS: Persistent high PCR levels always preceded virus isolation and may be the first indication of organ involvement and thus early treatment. PCR scores were consistently useful as indicators of drug efficacy and for monitoring of treatment.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções por Citomegalovirus/diagnóstico , DNA Viral/sangue , Infecções por HIV/complicações , Retinite/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/complicações , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/complicações , DNA Viral/genética , Estudos de Avaliação como Assunto , Humanos , Leucócitos/microbiologia , Reação em Cadeia da Polimerase/métodos , Retinite/complicações
6.
AIDS ; 8(5): 583-90, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7914731

RESUMO

OBJECTIVE: To determine whether activation of Epstein-Barr virus (EBV) replication in tumour cells of AIDS-related non-Hodgkin's lymphoma (ARNHL) is correlated with CD4+ cell counts and influences antibody response to EBV [anti-Z Epstein-Barr replicative activator (ZEBRA), anti-early antigen (EA), anti-viral capsid antigen (VCA)]. DESIGN: Retrospective study based on immunohistochemistry and in situ hybridization to detect EBV replicative gene products in tissue samples from patients affected by ARNHL and correlation with CD4+ cell counts and results of EBV serology (including anti-ZEBRA activity) in sera from the same patients. METHODS: Seventeen out of 22 cases of ARNHL were selected for the presence of EBV [Epstein-Barr early region (EBER) RNA-positive]. Immunohistochemistry was performed with anti-ZEBRA, anti-EA-restricted, anti-VCA antibodies and in situ hybridization with BHLF1/NotI oligoprobes on tumour samples. Results were statistically correlated with those of CD4+ cell counts (17 out of 17) and with anti-EBV antibody titres (13 out of 17) assessed using standard immunofluorescence method and enzyme-linked immunosorbent assay procedure using recombinant ZEBRA protein and synthetic peptides as antigens. RESULTS: BZLF1 (ZEBRA) or early gene products (EA-R and EA-D/BHLF1/NotI) were detected in a small proportion (< 0.01-5%) of tumour cells in eight of these 17 cases by immunohistochemistry and in situ hybridization. Demonstration of replicative gene expression did not correlate with either low CD4+ cell counts (P > 0.05) or anti-EBV antibody titres (P > 0.05). Anti-ZEBRA activity was not significantly increased in patients affected with ARNHL, the cells of which expressed replicative gene products (P > 0.05). CONCLUSION: The degree of immunodeficiency does not clearly enhance replicative gene expression in tumour cells of ARNHL. EBV serology, including anti-ZEBRA activity, is not a reliable tool for predicting the occurrence of such proliferations.


Assuntos
Anticorpos Antivirais/sangue , Linfócitos T CD4-Positivos , Proteínas do Capsídeo , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/genética , Linfoma Relacionado a AIDS/microbiologia , Proteínas Virais , Ativação Viral , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Anticorpos Antivirais/biossíntese , Especificidade de Anticorpos , Antígenos Virais/biossíntese , Antígenos Virais/genética , Antígenos Virais/imunologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Ensaio de Imunoadsorção Enzimática , Antígenos Nucleares do Vírus Epstein-Barr , Feminino , Infecções por Herpesviridae/complicações , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/fisiologia , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transativadores/biossíntese , Transativadores/genética , Transativadores/imunologia , Infecções Tumorais por Vírus/complicações , Replicação Viral
7.
J Immunol Methods ; 182(2): 227-34, 1995 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-7540641

RESUMO

Three peptides corresponding respectively to two Epstein-Barr viral epitopes and to the c-erbB-2 oncogene product were synthesized with the aim of developing an immunoenzymatic assay. Preliminary experiments indicated that the efficiency of the assay was profoundly affected by the nature of the solid phase for each peptide. In order to optimize the assay the three peptides were covalently coupled to functionalized polystyrene microplates which were used to immobilize both haptens and nucleic acids in a previous study. The results obtained indicate that the use of the carboxylated surfaces permits the linking strategy to be adapted to each peptide. Moreover, high sensitivities (5 x 10(-10)-1 x 10(-13) M) were obtained using amounts of the peptides much lower than those used in the standard system.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Técnicas Imunológicas , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Antígenos Virais/genética , Antígenos Virais/imunologia , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Epitopos/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Técnicas Imunológicas/instrumentação , Técnicas Imunológicas/estatística & dados numéricos , Camundongos , Dados de Sequência Molecular , Peptídeos/genética , Poliestirenos , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Sensibilidade e Especificidade
8.
Res Microbiol ; 148(8): 683-90, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9765853

RESUMO

16S rRNA RFLP analysis of Mycobacterium avium complex (MAC) strains isolated from 25 AIDS patients led to identification of seven ribotypes. The same ribotype was determined for strains from 19 patients with and without disseminated disease. When isolates representing the seven ribotypes were examined for their internal transcribed spacer (ITS) between the 16S and 23S rRNA gene nucleotide sequence, four different sequences, including a new ITS type, were recovered. All isolates with the most common ribotype belonged to the sequevar Mav-B. When MAC strains from AIDS patients were compared by ITS sequencing and ribotyping, a significant degree of homogeneity was observed. The discriminatory level reached with ribotyping might be useful for grouping isolates from different clinical sources.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Complexo Mycobacterium avium/classificação , Complexo Mycobacterium avium/genética , Infecção por Mycobacterium avium-intracellulare/microbiologia , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Sequência de Bases , Humanos , Técnicas de Sonda Molecular , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Alinhamento de Sequência
9.
Radiat Res ; 159(2): 268-73, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12537533

RESUMO

Epstein-Barr virus (EBV), a member of the gamma-herpesvirus family, is involved in the development of several diseases, and the infection is believed to persist for life in latent form. Ionizing radiation at clinically relevant doses may increase the amount of virus reactivation in B cells, and the combination of radiation with stress could amplify EBV reactivation. In vitro experiments were performed on several cell lines, including EBV-positive Burkitt lymphoma cells. The presence of the immediate-early protein ZEBRA, which is a hallmark of EBV reactivation, was evaluated using flow cytometry, which enabled us to measure the percentage of ZEBRA-positive cells. The process was studied previously in the EBV-positive Burkitt lymphoma cell line B95-8. Forty-eight hours after irradiation alone, 13.6 and 19.9% ZEBRA-positive cells were observed at 2 and 4 Gy, respectively, compared to the basal level of 1.85%. Thus irradiation induces EBV reactivation. The addition of a glucocorticoid (the final effector of the stress response) had no effect on EBV reactivation in our model. However, the combination of radiation and treatment with a glucocorticoid (dexamethasone) increased the expression of ZEBRA in B95-8 cells (15.8 and 28.75% of the cells was positive at 24 and 48 h after gamma irradiation, respectively). Thus the combination of gamma radiation and a glucocorticoid may play an important role in EBV reactivation.


Assuntos
Citometria de Fluxo/métodos , Raios gama/efeitos adversos , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 4/efeitos da radiação , Linfócitos/virologia , Proteínas Virais , Ativação Viral/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Proteínas de Ligação a DNA/metabolismo , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos da radiação , Glucocorticoides/efeitos adversos , Herpesvirus Humano 4/metabolismo , Humanos , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Microscopia de Fluorescência , Transativadores/metabolismo , Células Tumorais Cultivadas
10.
FEMS Microbiol Lett ; 124(1): 75-9, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7528153

RESUMO

Ribotyping was investigated as a means of distinguishing ten different serotyped reference strains and seven epidemiologically unrelated isolates of Mycobacterium avium-Mycobacterium intracellulare using a labelled 16S rDNA probe. Thirteen restriction enzymes were screened towards an accurate discrimination of strains. Two selected restriction enzymes (SacI and ClaI) enabled us to classify the 17 strains into ten ribotypes with an index of discrimination of 0.897. Typeability and reproducibility of the method reached 100%. The patterns obtained exhibited polymorphism of RE fragments within and outside the 16S rRNA gene and may be useful for epidemiological studies.


Assuntos
Impressões Digitais de DNA/métodos , Sondas de DNA , Complexo Mycobacterium avium/genética , Mycobacterium avium/genética , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Sequência de Bases , DNA Bacteriano/análise , Desoxirribonucleases de Sítio Específico do Tipo II , Dados de Sequência Molecular , Mycobacterium avium/classificação , Complexo Mycobacterium avium/classificação , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
J Virol Methods ; 45(3): 259-76, 1993 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-8106600

RESUMO

The polymerase chain reaction (PCR) as applied to human cytomegalovirus (HCMV) detection should provide a valuable tool for rapid, reliable diagnosis of infection, thereby allowing prompt treatment. However, to date the high sensitivity of this technique and the lack of semi-quantitative interpretation have hindered establishing its validity for diagnosing systemic infection. We describe a rapid, simple, semi-quantitative PCR technique for HCMV detection. The validity of the technique was tested objectively by analyzing over 2000 leukocytes specimens by PCR and comparing the results with virus isolation from urine and blood in concomitant samples in the absence of any clinical data. It could thus be established that this technique had a sensitivity and specificity of 97%. When the PCR signal corresponded to > or = 8000 genome equivalents for 10(4) leukocytes, the predictive value for viremia was 86%. This semi-quantitative PCR technique should allow rapid diagnosis of systemic infection and provide a reliable means of monitoring clearance of CMV from blood during drug therapy.


Assuntos
Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Urina/microbiologia , Viremia/diagnóstico , Síndrome da Imunodeficiência Adquirida/complicações , Sequência de Bases , Southern Blotting , Citomegalovirus/genética , Citomegalovirus/crescimento & desenvolvimento , Infecções por Citomegalovirus/complicações , DNA Viral/sangue , DNA Viral/urina , Humanos , Leucócitos/microbiologia , Transplante de Fígado , Dados de Sequência Molecular , Sensibilidade e Especificidade , Cultura de Vírus , Eliminação de Partículas Virais
12.
J Virol Methods ; 71(2): 211-8, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9626954

RESUMO

Epstein-Barr virus (EBV) is distributed widely throughout the world. Apart from a association with two geographically-restricted malignancies (Burkitt's lymphoma and nasopharyngeal carcinoma), EBV is thought to be implicated in the etiology of B-cell lymphoma in immunocompromised individuals. In these patients, monitoring the viral load in serum can provide useful information on the timing of the instigation of antiviral therapy, i.e. as soon as a rise is detected. PCR technology, owing to its high sensitivity, is used frequently in such situations. In order to gain further insight into the nature of the peripheral blood cells carrying the viral genome on a cell-by-cell basis, an in situ amplification technique was developed as a model using two cell lines growing in suspension, with the aim of distinguishing between EBV-positive and EBV-negative cells. Preliminary experiments were undertaken subsequently on clinical samples from patients with infectious mononucleosis and patients with lymphoma indicating that this technique might be useful clinically.


Assuntos
Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Mononucleose Infecciosa/virologia , Linfoma/virologia , Reação em Cadeia da Polimerase/métodos , Linfoma de Burkitt , Genoma Viral , Herpesvirus Humano 4/crescimento & desenvolvimento , Humanos , Hibridização In Situ/métodos , Linfoma/sangue , Células Tumorais Cultivadas
13.
J Virol Methods ; 56(2): 125-37, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8882643

RESUMO

The development of new in situ assessment of HCMV disease on endoscopical gastrointestinal biopsies from AIDS patients is described and compared with the viral load measured by semiquantitative solution-phase PCR (SQ-PCR). Ten biopsies were examined by viral isolation, standard histology, in situ hybridization (ISH), in situ PCR-hybridization (PCR-ISH) and SQ-PCR, using the same target sequence. The methods developed for in situ HCMV detection were HCMV primers, the plasmid pCMV 406-S, a vector-free-digoxigenin-labelled HCMV-362 probe and the pSK + MCS nonsense probe. Paraffin-embedded MRC5 cells, either HCMV-infected or uninfected served as controls of specificity for ISH. beta-Actin primers were designed as markers of DNA integrity. Computerized models of the PCR, solution-phase and in situ PCR on formalin-fixed DNA indicated that HCMV and beta-actin primers were efficient and specific. Nine biopsies were negative for HCMV by histology and virus isolation. SQ-PCR revealed 80,000; 80 and < 80 HCMV genomic equivalents in 6, 2 and 2 biopsies, respectively. In 8 biopsies, both ISH and PCR-ISH identified positive nuclei in the intestinal epithelium, with sparing of the lamina propria. This indicates that an improvement in in situ methods can help the timely diagnosis of HCMV infection. Direct in situ PCR with beta-actin primers showed a positive signal in all the nuclei in the tissue sections, whereas omission of Taq polymerase resulted in an absence of signal, implying optimal in situ PCR. The data suggest an early-stage reactivation of HCMV, possibly harboured in the intestinal epithelium.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , DNA Viral/análise , Sistema Digestório/virologia , Reação em Cadeia da Polimerase/métodos , Infecções Oportunistas Relacionadas com a AIDS/complicações , Infecções Oportunistas Relacionadas com a AIDS/patologia , Sequência de Bases , Citomegalovirus/genética , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/patologia , Sistema Digestório/patologia , Humanos , Hibridização In Situ , Dados de Sequência Molecular
14.
Carbohydr Res ; 327(4): 455-61, 2000 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-10990031

RESUMO

2,2,6,6-Tetramethyl-1-piperidinyloxy radical (TEMPO)-mediated oxidation of hyaluronan was studied at pH 10.2 and temperature of 0 degrees C with NaOCl as the primary oxidant. As with other polysaccharides, a high selectivity of oxidation was observed. The degradation of the polymer was essentially caused by the oxidation process. The primary oxidant and the pH of the reaction mixture did not alter the molecular weight of hyaluronan during oxidation. The kinetics of the oxidation process was investigated at different concentrations of reactants and the inorganic salts, NaBr, NaCl, and Na2SO4. An increase in the salt concentration in the mixture causes a major decrease in the rate of the oxidation, and this decrease is independent of the nature of the salt.


Assuntos
Óxidos N-Cíclicos/farmacologia , Ácido Hialurônico/metabolismo , Sais/farmacologia , Catálise , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Peso Molecular , Oxirredução/efeitos dos fármacos , Percloratos/farmacologia , Compostos de Sódio/farmacologia , Espectrofotometria Infravermelho , Marcadores de Spin , Temperatura
15.
Med Hypotheses ; 58(4): 291-2, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12027522

RESUMO

Several recent epidemiological studies have shown that vaccinations against biological warfare using pertussis as an adjuvant were associated with the Gulf war syndrome. If such epidemiological findings are confirmed, we propose that the use of pertussis as an adjuvant could trigger neurodegeneration through induction of interleukin-1beta secretion in the brain. In turn, neuronal lesions may be sustained by stress or neurotoxic chemical combinations. Particular susceptibility for IL-1beta secretion and potential distant neuronal damage could provide an explanation for the diversity of the symptoms observed on veterans.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Síndrome do Golfo Pérsico/etiologia , Vacina contra Coqueluche/efeitos adversos , Vacinação/efeitos adversos , Adulto , Barreira Hematoencefálica , Encéfalo/metabolismo , Encéfalo/patologia , Ativação Enzimática , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Interleucina-1/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Degeneração Neural/etiologia , Degeneração Neural/patologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/patologia
16.
Bull Cancer ; 81(2): 114-8, 1994 Feb.
Artigo em Francês | MEDLINE | ID: mdl-7894116

RESUMO

Epstein-Barr virus (EBV) is present in up to 40% of Hodgkin's disease (HD). The viral genomes remain latent within Reed-Sternberg cells (RS cells), but the recent detection of Zebra protein in rare neoplastic cells of a few EBV+ HD cases, suggests an activation of EBV replication. We have studied fifty HD cases containing EBV genomes and expressing LMP1 protein (including five AIDS-related cases), by immunohistochemistry with anti-Zebra antibodies. Four of these cases (all HIV-) showed Zebra+ tumor cells. One of these four cases showed numerous Zebra+ neoplastic cells (approximately 1% of tumor cells) and positive staining for EA-R protein, thus indicating early gene expression. In situ hybridization with biotinylated BamHI W probe revealed in this case, a signal of unusual strength within some Reed-Sternberg cells, probably related to increased number of EBV genomes, thus suggesting EBV replication. Viral replication was finally confirmed in this case, by the detection of BLLF1 transcripts (encoding for the membrane antigen gp 350/220) using reverse transcriptase and polymerase chain reaction. Thus, a very few Zebra+ neoplastic cells are concerned by viral replication, most of them harboring EBV involved in an abortive, instead of a full lytic cycle. EBV replication in RS cells remains an exceptional event, but may provide clues to immunologic mechanisms of control of viral latency. Clinical implications need further investigations.


Assuntos
Herpesvirus Humano 4/genética , Doença de Hodgkin/virologia , Proteínas Virais/imunologia , Replicação Viral , Adulto , Proteínas de Ligação a DNA/imunologia , Herpesvirus Humano 4/imunologia , Doença de Hodgkin/imunologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Proteínas Virais/genética
17.
Presse Med ; 31(1 Pt 1): 3-9, 2002 Jan 12.
Artigo em Francês | MEDLINE | ID: mdl-11826584

RESUMO

SPARSE DATA: The Gulf war syndrome remains a little know entity since its first appearance 10 years ago. The objective of our work was to synthesize the data published on the subject in the scientific literature. We analysed the results of American and English epidemiological surveys, from which it was difficult to distinguish the existence of a univocal syndrome. IMPRECISE DEFINITION: It is difficult to give a clear clinical definition of the syndrome, the signs of which fluctuate depending on the studies. Chronic fatigue is frequently associated with the Gulf war syndrome, although some studies have described electrophysiological neurological lesions. NUMEROUS HYPOTHESES: The role of stress, vaccinations and their adjuvants, exposition to neurotoxic substances and weak uranium have been incriminated. We propose that multiple factors be integrated in the research for the genesis of this atypic syndrome.


Assuntos
Síndrome do Golfo Pérsico , Animais , Inglaterra , Síndrome de Fadiga Crônica/diagnóstico , Humanos , Doenças do Sistema Nervoso/diagnóstico , Síndrome do Golfo Pérsico/diagnóstico , Síndrome do Golfo Pérsico/epidemiologia , Síndrome do Golfo Pérsico/etiologia , Estresse Fisiológico/complicações , Estados Unidos
18.
Clin Pharmacol Ther ; 90(4): 561-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21918510

RESUMO

Paraoxonase-1 (PON1) Q192R polymorphism was recently suggested to determine per se clopidogrel response on major cardiovascular events (MACEs). We assessed the impact of PON1, CYP2C19, and ABCB1 polymorphisms on MACE in clopidogrel-treated acute myocardial infarction (AMI) patients (N = 2,210), including those undergoing percutaneous coronary intervention (PCI) (n = 1,538). PON1 polymorphism was not associated with increased risk of in-hospital death and MACEs at 1 year (adjusted hazard ratio (HR) 1.03, 95% confidence interval (CI) 0.66-1.61 and adjusted HR 0.77, 95% CI 0.42-1.41 for QQ versus RR in all and PCI patients, respectively). The presence of two CYP2C19 loss-of-function (LOF) alleles was associated with the risk of in-hospital death and MACEs at 1 year in the overall population (adjusted odds ratio (OR) 3.67, 95% CI 1.05-12.80 and adjusted HR 1.96, 95% CI 1.08-3.54) and in PCI patients (adjusted OR 6.87, 95% CI 2.52-18.72 and adjusted HR 3.06, 95% CI 1.47-6.41). Unlike CYP2C19 polymorphism, PON1 (Q192R) polymorphism is not a major pharmacogenetic contributor of clinical response to clopidogrel in AMI patients.


Assuntos
Arildialquilfosfatase/genética , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/genética , Polimorfismo Genético/genética , Ticlopidina/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Feminino , Seguimentos , Genótipo , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , Sistema de Registros , Ticlopidina/uso terapêutico , Resultado do Tratamento
19.
Aliment Pharmacol Ther ; 34(2): 188-95, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21615760

RESUMO

BACKGROUND: Surveillance colonoscopy is recommended for inflammatory bowel disease (IBD) patients with longstanding extensive colitis (LEC). AIMS: To assess modalities and results of colonoscopic surveillance in a subset of CESAME cohort patients at high risk of colorectal cancer (CRC) and followed in university French hospitals. METHODS: Among 910 eligible patients with more than a 7-year history of extensive colitis at CESAME enrolment, 685 patients completed a questionnaire on surveillance colonoscopy and 102 were excluded because of prior proctocolectomy. Finally, 583 patients provided information spanning a median period of 41months (IQR 38-43) between cohort enrolment and the end of follow-up. Details of the colonoscopic procedures and histological findings were obtained for 440 colonoscopies in 270 patients. RESULTS: Only 54% (n=312) of the patients with LEC had at least one surveillance colonoscopy during the study period, with marked variations across the nine participating centres (27% to 70%, P≤0.0001). Surveillance rate was significantly lower in Crohn's colitis than in ulcerative colitis (UC) (48% vs. 69%, P≤0.0001). Independent predictors of colonoscopic surveillance were male gender, UC IBD subtype, longer disease duration, previous history of CRC and disease management in a centre with large IBD population. Random biopsies, targeted biopsies and chromoendoscopy were performed during respectively 71%, 27 and 30% of surveillance colonoscopies. Two cases of high-grade dysplasia were detected in patients undergoing colonoscopic surveillance. Two advanced-stage CRC were diagnosed in patients who did not have colonosocopic surveillance. CONCLUSIONS: Colonoscopic surveillance rate is low in IBD patients with longstanding extensive colitis.


Assuntos
Colite Ulcerativa/epidemiologia , Colonoscopia/estatística & dados numéricos , Adulto , Estudos de Coortes , Colite Ulcerativa/diagnóstico , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Prevalência , Inquéritos e Questionários , Fatores de Tempo
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