RESUMO
Polyglutamine pathologies are neurodegenerative diseases that manifest both general polyglutamine toxicity and mutant protein-specific effects. Dentatorubral-pallidoluysian Atrophy (DRPLA) is one of these disorders caused by mutations in the Atrophin-1 protein. We have generated several models for DRPLA in Drosophila and analysed the mechanisms of cellular and organism toxicity. Our genetic and ultrastructural analysis of neurodegeneration suggests that autophagy may have a role in cellular degeneration when polyglutamine proteins are overexpressed in neuronal and glial cells. Clearance of autophagic organelles is blocked at the lysosomal level after correct fusion between autophagosomes and lysosomes. This leads to accumulation of autofluorescent pigments and proteinaceous residues usually degraded by the autophagy-lysosome system. Under these circumstances, further pharmacological and genetic induction of autophagy does not rescue neurodegeneration by polyglutamine Atrophins, in contrast to many other neurodegenerative conditions. Our data thus provide a crucial insight into the specific mechanism of a polyglutamine disease and reveal important differences in the role of autophagy with respect to other diseases of the same family.
Assuntos
Autofagia , Proteínas de Drosophila/metabolismo , Epilepsias Mioclônicas Progressivas/patologia , Proteínas do Tecido Nervoso/metabolismo , Fatores de Transcrição/metabolismo , Animais , Modelos Animais de Doenças , Drosophila , Proteínas de Drosophila/genética , Humanos , Mutação , Epilepsias Mioclônicas Progressivas/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/toxicidade , Doenças Neurodegenerativas/patologia , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Peptídeos/toxicidade , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Brief intervention by a health professional can substantially increase smoking cessation rates among patients. However, few studies have collected information on tobacco use and training to provide cessation counselling among health professional students. OBJECTIVE: To examine tobacco use prevalence and tobacco cessation training among students pursuing advanced degrees in health professions. METHODS: The Global Health Professions Student Survey (GHPSS) has been conducted among third-year students attending dental, medical, nursing and pharmacy schools. The GHPSS was conducted in schools during regular lectures and class sessions. GHPSS follows an anonymous, self-administered format for data collection. RESULTS: The GHPSS was completed by at least one of the four target disciplines in 31 countries between 2005 and 2007 for a total of 80 survey sites. In 47 of the 80 sites, over 20% of the students currently smoked cigarettes; and in 29 of 77 sites, over 10% of the students currently used other tobacco products. GHPSS data showed that the majority of health professional students recognised that they are role models in society, believed that they should receive training on counselling patients to quit using tobacco, but in 73 of 80 sites less than 40% of the students reported they received such training. CONCLUSIONS: Health professional schools, public health organisations and education officials should discourage tobacco use among health professionals and work together to design and implement programmes that train all health professionals in effective cessation counselling techniques. If the goal of the tobacco control community is to reduce substantially the use of tobacco products, then resources should be invested in improving the quality of education of health professionals with respect to tobacco control.
Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Aconselhamento , Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Estudantes de Ciências da Saúde/psicologia , Adulto , Feminino , Humanos , Masculino , Papel ProfissionalRESUMO
Two new fluorene derivatized 1,10-phenanthroline ligands and related tris-chelate Ru(II) or Zn(II) coordination complexes have been synthesised. The linear and nonlinear (two-photon induced fluorescence) photophysical measurements have contributed to highlight the possibility to tune the absorption spectral range and excited lifetime, depending on ligand substitution and nature of the metal. More significantly, the observation of two-photon absorption (TPA) associated with long-lived metal-to-ligand charge-transfer (MLCT) excited states in the Ru(II)-based chromophores, opens a wide range of applications in the near infrared.
Assuntos
Compostos Organometálicos/síntese química , Rutênio/química , Zinco/química , Fluorenos/síntese química , Fluorenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Organometálicos/química , Fenantrolinas/síntese química , Fenantrolinas/químicaRESUMO
Bulbing was studied in shallot plants cultured in vitro. Bulbing occurred under a 16 h photoperiod with fluorescent + incandescent light and 30-50 g 1(-1) sucrose in the culture medium. Exogenous gibberellin (10 microM GA3) inhibited leaf and root growth and bulbing. When added to the medium at a concentration of 10 microM, three inhibitors of gibberellin biosynthesis (ancymidol, flurprimidol and paclobutrazol) promoted bulb formation and the percentage of bulbing. When ancymidol was used in combination with GA3, it did not reverse the effect of GA3 applied alone. Under treatments with 30-70 g l(-1) sucrose, bulbing ratios greater than those found in control plants were achieved by addition of ancymidol, and bulb fresh weight was increased in the same way. Ancymidol caused a 66% decrease in sucrose content in leaf bases but greatly increased the glucose, fructose and fructan contents. The increase in fructan content by ancymidol could result from the three-fold rise in total [14C]sucrose uptake per plant from the culture medium associated with a marked increase in leaf base labelling at the expense of root labelling. The possible role of ancymidol is discussed and evidence supports a major regulatory role for gibberellins in bulbing.
Assuntos
Allium/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Caules de Planta/crescimento & desenvolvimento , Pirimidinas/farmacologia , Sacarose/farmacologia , Allium/efeitos dos fármacos , Allium/efeitos da radiação , Transporte Biológico , Radioisótopos de Carbono , Técnicas de Cultura , Frutanos/metabolismo , Frutose/metabolismo , Giberelinas/antagonistas & inibidores , Giberelinas/biossíntese , Glucose/metabolismo , Luz , Fotoperíodo , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Caules de Planta/efeitos dos fármacos , Caules de Planta/efeitos da radiação , Triazóis/farmacologiaRESUMO
The objective of this study was to evaluate the antiretroviral efficacy and safety of ritonavir (600 mg twice a day [b.i.d.])-saquinavir (400 mg b.i.d.) compared to ritonavir (600 mg b.i.d.) in patients pretreated and receiving continued treatment with two nucleoside analogs. The study was placebo controlled, randomized, and double blind. Inclusion criteria included protease inhibitor naive status and a viral load of >10,000 copies/ml. The main end point was viral load at week 24. Forty-seven patients were included (25 given ritonavir and 22 given ritonavir-saquinavir) and monitored until week 48. At inclusion, 23% had had at least one AIDS-defining event. Previous treatment durations (mean and standard deviation) were 42 +/- 25 and 37 +/- 23 months, viral loads were 4.75 +/- 0.62 and 4.76 +/- 0.50 log(10) copies/ml, and CD4 cell counts were 236 +/- 126 and 234 +/- 125/mm(3) in the ritonavir and ritonavir-saquinavir groups, respectively. At week 24, viral loads were 2.81 +/- 1.48 and 2.08 +/- 1.14 log(10) copies/ml (P = 0.04) and CD4 cell counts were 330 +/- 151 and 364 +/- 185/mm(3) (P = 0.49) in the ritonavir and ritonavir-saquinavir groups, respectively. Similar results were observed at week 48. Moreover, at week 48, 40 and 68% (P = 0.05) and 28 and 59% (P = 0.03) of patients achieved viral suppression at below 200 and 50 copies/ml in the ritonavir and ritonavir-saquinavir groups, respectively. At week 24, six patients in the ritonavir group but only one in the ritonavir-saquinavir group had key mutations conferring resistance to protease inhibitors. Clinical and biological tolerances were similar in both groups. In nucleoside analog-pretreated patients, ritonavir-saquinavir has higher antiretroviral efficacy than and is as well tolerated as ritonavir alone.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Ritonavir/uso terapêutico , Saquinavir/uso terapêutico , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Infecções por HIV/sangue , Infecções por HIV/virologia , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/sangue , Humanos , Testes de Função Hepática , Masculino , Ritonavir/efeitos adversos , Ritonavir/sangue , Saquinavir/efeitos adversos , Saquinavir/sangue , Carga ViralRESUMO
The effect of selenite on the growth rate and protein synthesis has been investigated in Rhodobacter sphaeroides. This photosynthetic bacterium efficiently reduces selenite with intracellular accumulation under both dark aerobic and anaerobic photosynthetic conditions. Addition of 1 mM selenite under these two growth conditions does not affect the final cell density, although a marked slowdown in growth rate is observed under aerobic growth. The proteome analysis of selenite response by two-dimensional gel electrophoresis shows an enhanced synthesis of some chaperones, an elongation factor, and enzymes associated to oxidative stress. The induction of these antioxidant proteins confirms that the major toxic effect of selenite is the formation of reactive oxygen species during its metabolism. In addition, we show that one mutant unable to precipitate selenite, selected from a transposon library, is affected in the smoK gene. This encodes a constituent of a putative ABC transporter implicated in the uptake of polyols. This mutant is less sensitive to selenite and does not express stress proteins identified in the wild type in response to selenite. This suggests that the entry of selenite into the cytoplasm is mediated by a polyol transporter in R. sphaeroides.
Assuntos
Proteínas de Bactérias/biossíntese , Rhodobacter sphaeroides/efeitos dos fármacos , Selenito de Sódio/farmacologia , Aerobiose , Sequência de Aminoácidos , Anaerobiose , Proteínas de Bactérias/química , Meios de Cultura , Dados de Sequência Molecular , Mutação , Oxirredução , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/crescimento & desenvolvimento , Rhodobacter sphaeroides/metabolismo , Selenito de Sódio/metabolismoRESUMO
Three hundred and three strains of group A streptococci (GAS) isolated from adults with pharyngitis were tested to evaluate their phenotype of resistance to macrolides-lincosamides and to search for macrolide resistance genes. MICs of clarithromycin were determined. The overall rate of resistance to both erythromycin and clarithromycin was 9.6%. Constitutive, inducible and M phenotypes of resistance were detected in 4.3, 2 and 3.3% of strains, respectively. All constitutive phenotypes harboured ermB genes, whereas inducible phenotypes had the ermTR gene and M phenotypes had the mefA gene. In France, the current resistance rate of GAS to erythromycin and clarithromycin remains low.
Assuntos
Antibacterianos , Farmacorresistência Bacteriana/genética , Infecções Estreptocócicas/genética , Streptococcus pyogenes/genética , Tonsilite/genética , Tonsila Faríngea/efeitos dos fármacos , Tonsila Faríngea/microbiologia , Adolescente , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Criança , França , Humanos , Macrolídeos , Fenótipo , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/isolamento & purificação , Tonsilite/tratamento farmacológico , Tonsilite/microbiologiaRESUMO
Lentiviruses, among which is caprine arthritis encephalitis virus (CAEV), are known to concomitantly assemble and bud at the plasma membrane of infected cells, in a C-type defined pathway. Electron microscopy analysis of CAEV-infected cells demonstrated viral particles budding at the plasma membrane and into intracellular membrane-surrounded vesicles. Furthermore, nonenveloped immature virus-like particles, resembling intracytoplasmic type-A particles (ICAPs), accumulated within the cytoplasm of those cells. Fractionation on sucrose density gradients of cytoplasmic lysates from CAEV-infected cells revealed that enveloped immature or mature viral particles had a density of 1.16--1.17 g/ml, whereas ICAPs sedimented at a density of 1.2--1.27 g/ml. Endogenous reverse transcriptase activity was only associated with the 1.16--1.17 g/ml density particles despite the presence of viral RNA in both populations. The intracellular enveloped particles were found to be infectious. The CAEV Gag precursor by itself was shown to direct assembly, budding, and release of immature virus-like particles when expressed in goat primary synovial membrane cells using the same pathways of assembly and budding as observed in CAEV-infected cells. These data suggest that CAEV assembly, driven by the Gag precursor, could unusually proceed via two simultaneous pathways characteristic of type-C and type-B/D retroviruses.
Assuntos
Vírus da Artrite-Encefalite Caprina/fisiologia , Montagem de Vírus , Replicação Viral , Animais , Vírus da Artrite-Encefalite Caprina/patogenicidade , Vírus da Artrite-Encefalite Caprina/ultraestrutura , Células Cultivadas , Produtos do Gene gag/metabolismo , Doenças das Cabras/virologia , Cabras , Infecções por Lentivirus/veterinária , Infecções por Lentivirus/virologia , Microscopia Eletrônica , Precursores de Proteínas/metabolismo , DNA Polimerase Dirigida por RNA/metabolismo , Membrana Sinovial/citologia , Membrana Sinovial/virologia , Vírion/metabolismo , Vírion/patogenicidade , Vírion/ultraestruturaRESUMO
Neurodegenerative diseases are characterized by the presence of filamentous aggregates of proteins. We previously established that lithostathine is a protein overexpressed in the pre-clinical stages of Alzheimer's disease. Furthermore, it is present in the pathognomonic lesions associated with Alzheimer's disease. After self-proteolysis, the N-terminally truncated form of lithostathine leads to the formation of fibrillar aggregates. Here we observed using atomic force microscopy that these aggregates consisted of a network of protofibrils, each of which had a twisted appearance. Electron microscopy and image analysis showed that this twisted protofibril has a quadruple helical structure. Three-dimensional X-ray structural data and the results of biochemical experiments showed that when forming a protofibril, lithostathine was first assembled via lateral hydrophobic interactions into a tetramer. Each tetramer then linked up with another tetramer as the result of longitudinal electrostatic interactions. All these results were used to build a structural model for the lithostathine protofibril called the quadruple-helical filament (QHF-litho). In conclusion, lithostathine strongly resembles the prion protein in its dramatic proteolysis and amyloid proteins in its ability to form fibrils.
Assuntos
Doença de Alzheimer/metabolismo , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/ultraestrutura , Sequência de Aminoácidos , Cristalografia por Raios X , Humanos , Processamento de Imagem Assistida por Computador , Litostatina , Substâncias Macromoleculares , Microscopia de Força Atômica , Microscopia Eletrônica , Modelos Moleculares , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/ultraestrutura , Conformação Proteica , Estrutura Secundária de Proteína , Deleção de SequênciaRESUMO
BACKGROUND: Ritonavir is a potent inhibitor of cytochrome P4503A4 that strongly increases saquinavir bioavailability. In this study we assessed the safety and antiretroviral efficacy of the combination of these two compounds in patients pretreated and receiving continued treatment with zidovudine and lamivudine who were protease inhibitor naive and who had a CD4 cell counts below 200/mm3. METHODS: In this 48-week pilot study, all patients received 600 mg ritonavir and 400 mg saquinavir twice daily. Administration of zidovudine and lamivudine was continued without a change in previous doses. Viral load, CD4 cell count, and the emergence of resistance to the two protease inhibitors were evaluated repeatedly up to week 48. RESULTS: Sixteen patients were included in the study. Previous nucleoside analog treatment duration was 48+/-22 months (mean +/- SD). Two patients quit taking both protease inhibitors within 2 weeks. The ritonavir dose had to be reduced in 10 other patients because of side effects. Between inclusion and week 48, plasma viremia varied from 4.87+/-0.43 to 3.00+/-1.29 log10 copies/mL and CD4 cell counts ranged from 98+/-61 to 250+/-139/mm3. Ten patients (63%) had viral loads below 200 copies/mL and 7 (44%) had viral loads below 50 copies/mL. A single key mutation that conferred ritonavir resistance I84V and V82A/V developed in two patients. A mutation at codon 54 developed in another patient. These mutations were associated with repeated cessations of antiretroviral treatment. No lipodystrophy was observed. CONCLUSION: Ritonavir and saquinavir in combination are quite well tolerated and induce a high and sustained antiretroviral efficacy. A four-drug combination that includes these two protease inhibitors should be considered as a first line of treatment in patients with low CD4 cell counts.
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Inibidores da Protease de HIV/uso terapêutico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Ritonavir/uso terapêutico , Saquinavir/uso terapêutico , Zidovudina/uso terapêutico , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/imunologia , Adulto , Contagem de Linfócito CD4/efeitos dos fármacos , DNA Viral/efeitos dos fármacos , DNA Viral/genética , Esquema de Medicação , Resistência a Medicamentos , Quimioterapia Combinada , Feminino , Genótipo , Inibidores da Protease de HIV/efeitos adversos , Humanos , Lamivudina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Projetos Piloto , Reação em Cadeia da Polimerase , Inibidores da Transcriptase Reversa/efeitos adversos , Ritonavir/efeitos adversos , Saquinavir/efeitos adversos , Índice de Gravidade de Doença , Fatores de Tempo , Carga Viral , Zidovudina/efeitos adversosRESUMO
The electrical activity in heart is generated in the sinoatrial node and then propagates to the atrial and ventricular tissues. The gap junction channels that couple the myocytes are responsible for this propagation process. The gap junction channels are dodecamers of transmembrane proteins of the connexin (Cx) family. Three members of this family have been demonstrated to be synthesized in the cardiomyocytes: Cx40, Cx43, and Cx45. In addition, each of them has been shown to form channels with unique and specific electrophysiological properties. Understanding the conduction phenomenon requires detailed knowledge of the spatiotemporal expression pattern of these Cxs in heart. The expression patterns of Cx40 and Cx43 have been previously described in the adult heart and during its development. Here we report the expression of Cx45 gene products in mouse heart from the stage of the first contractions (8.5 days postcoitum [dpc]) to the adult stage. The Cx45 gene transcript was demonstrated by reverse transcriptase-polymerase chain reaction experiments to be present in heart at all stages investigated. Between 8.5 and 10.5 dpc it was shown by in situ hybridization to be expressed in low amounts in all cardiac compartments (including the inflow and outflow tracts and the atrioventricular canal) and then to be downregulated from 11 to 12 dpc onward. At subsequent fetal stages, the transcript was weakly detected in the ventricles, with the most distinct expression in the outflow tract. Cx45 protein was demonstrated by immunofluorescence microscopy to be expressed in the myocytes of young embryonic hearts (8.5 to 9.5 dpc). However, beyond 10.5 dpc the protein was no longer detected with this technique in the embryonic, fetal, or neonatal working myocardium, although it could be shown by immunoblotting that the protein was still synthesized in neonatal heart. In the major part of adult heart, Cx45 was undetectable. It was, however, clearly seen in the anterior regions of the interventricular septum and in trace amounts in some small foci dispersed in the ventricular free walls. Cx45 gene is the first Cx gene so far demonstrated to be activated in heart at the stage of the first contractions. The coordination of myocytes during the slow peristaltic contractions that occur at this stage would thus appear to be controlled by the Cx45 channels.
Assuntos
Conexinas/genética , Regulação para Baixo/genética , Regulação da Expressão Gênica no Desenvolvimento , Coração/embriologia , Sequência de Aminoácidos , Animais , Elementos Antissenso (Genética) , Conexinas/análise , Conexinas/imunologia , Feminino , Feto/citologia , Imunofluorescência , Células HeLa , Humanos , Hibridização In Situ , Fígado/citologia , Camundongos , Microscopia Eletrônica , Dados de Sequência Molecular , Miocárdio/química , Miocárdio/metabolismo , Ovário/química , Ovário/ultraestrutura , Coelhos , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica/fisiologiaRESUMO
T-cell receptors (TCRs) upon binding to peptide-MHC ligands transduce signals in T lymphocytes. Tyrosine phosphorylations in the cytoplasmic domains of the CD3 (gammadeltaepsilon) and zeta subunits of the TCR complex by Src family kinases initiate the signaling cascades via docking and activation of ZAP-70 kinase and other signaling components. We examined the role of the low-density detergent-insoluble membranes (DIMs) in TCR signaling. Using mouse thymocytes as a model, we characterized the structural organization of DIMs in detail. We then demonstrated that TCR engagement triggered an immediate increase in the amount of TCR/CD3 present in DIMs, which directly involves the engaged receptor complexes. TCR/CD3 recruitment is accompanied by the accumulation of a series of prominent tyrosine-phosphorylated substrates and by an increase of the Lck activity in DIMs. Upon TCR stimulation, the DIM-associated receptor complexes are highly enriched in the hyperphosphorylated p23 zeta chains, contain most of the TCR/CD3-associated, phosphorylation-activated ZAP-70 kinases and seem to integrate into higher order, multiple tyrosine-phosphorylated substrate-containing protein complexes. The TCR/CD3 recruitment was found to depend on the activity of Src family kinases. We thus provide the first demonstration of recuitment of TCR/CD3 to DIMs upon receptor stimulation and propose it as a mechanism whereby TCR engagement is coupled to downstream signaling cascades.
Assuntos
Membranas Intracelulares/metabolismo , Complexo Receptor-CD3 de Antígeno de Linfócitos T/análise , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais/imunologia , Animais , Compartimento Celular , Cetomacrogol , Detergentes , Inibidores Enzimáticos/farmacologia , Gangliosídeo G(M1)/análise , Glicosilfosfatidilinositóis/análise , Membranas Intracelulares/química , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Camundongos , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Tirosina Quinases/análise , Solubilidade , Timo/imunologia , Tirosina/metabolismo , Proteína-Tirosina Quinase ZAP-70 , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/fisiologiaRESUMO
The atomic force microscope (AFM) and the transmission electron microscope (TEM) have been used to study the morphology of isolated mouse thymocyte microdomains and Thy-1 antigen distribution at the surface of these structures. AFM images were recorded in air in the contact mode on membrane vesicles deposited on previously heated tissue culture plastic sheets and indirectly immunolabeled for Thy-1 expression with colloidal gold-conjugated secondary antibodies. AFM images of untreated plastic plates showed a very characteristic network of streaks 20-200 nm wide. Heating the plastic removed the streaks and provided flat surfaces (r.m.s. 1 nm). This substrate allowed strong adsorption and homogeneous spreading of the vesicles and easy manipulations during immunolabeling experiments. Vesicles flattened on the substrate without losing their morphology. The 10-nm membrane-bound gold beads were reproducibly imaged without degradation by repeated tip scanning. The observed microdomains had a mean diameter of 184 +/- 76 nm, and 65% of them were specifically labeled. Images obtained with the TEM on the same vesicles, deposited on carbon-coated grids and negatively stained, confirmed the AFM observations. The size distribution of the microdomains was quite similar, but the number of beads per vesicle was significantly higher, and 76% of the vesicles were labeled. The difference may be explained 1) by removal of beads from the vesicles in the additional washing step with water, which was necessary for the AFM; 2) by tip-sample convolution; and 3) by statistical fluctuations.
Assuntos
Linfócitos T/ultraestrutura , Antígenos Thy-1/análise , Antígenos Thy-1/ultraestrutura , Animais , Anticorpos , Membrana Celular/imunologia , Membrana Celular/ultraestrutura , Ouro , Camundongos , Camundongos Endogâmicos , Microscopia de Força Atômica/métodos , Microscopia Imunoeletrônica/métodos , Linfócitos T/imunologiaRESUMO
In order to test the hypothesis that a combination of protease inhibitors with nucleoside analogues-agents known to inhibit different steps of the human immunodeficiency virus (HIV) life cycle--is likely to prove more effective in reducing viral loads than either of those modalities alone, we performed a 60 week, open-label trial in 32 HIV-positive patients with depressed CD4 T lymphocyte cell counts but no active AIDS-defining illnesses. For the first 2 weeks, patients received 600 mg twice daily of liquid ritonavir, a protease inhibitor; then zidovudine 200 mg three times daily and zalcitabine 0.75 mg three times daily were added to the treatment regimen. Mononuclear blood cell fractions were analysed for infected cell levels, using a co-culture system. HIV-1 RNA in plasma was measured both by reverse transcriptase-polymerase chain reaction (RT-PCR) and reverse transcriptase quantitative PCR (QcRT-PCR); lymphocyte counts were determined by standard laboratory methods. In the 2 weeks of ritonavir therapy, both the mean count of infectious blood cells and plasma HIV RNA levels decreased dramatically. Mean CD4 cell counts increased from 173 cells/mm3 at baseline to 286 cells/mm3; CD8 cell counts rose from 951 cells/mm3 to 1,141 cells/mm3. With the introduction of the nucleoside analogues, infectious cell counts and plasma virus dropped another log unit to a nadir at 8 weeks, while CD4 T lymphocyte counts continued to rise slowly. By week 28, 12 patients had withdrawn due to adverse events, none of which were life-threatening. At week 36, infectious material could not be detected in the cells of 10 of the 17 remaining patients; by week 60, four of the seven patients with residual viraemia at week 24 had undergone viral relapse. After the introduction of a more palatable capsule formulation of ritonavir at week 52, infectious cells and plasma virus were undetectable in 50-60% of patients. The combination of protease inhibitors and nucleoside analogues significantly reduces HIV load, and in some patients may suppress viral activity for sustained periods.
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/administração & dosagem , Contagem de Linfócito CD4 , HIV-1 , RNA Viral/análise , Ritonavir/administração & dosagem , Zalcitabina/administração & dosagem , Zidovudina/administração & dosagem , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Fármacos Anti-HIV/efeitos adversos , Linfócitos T CD8-Positivos/fisiologia , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The efficacy and safety of clarithromycin and amoxicillin-clavulanate in the treatment of acute maxillary sinusitis was compared in an open multicenter outpatient study. Two hundred and eighty patients were randomly assigned to receive either clarithromycin 500 mg 12-hourly or amoxicillin-clavulanate 500 mg 8-hourly orally for 8 days. Clinical and radiologic signs and symptoms, and sinus culture were not significantly different in the two treatment groups. A clinical and radiological success or improvement was achieved after the end of treatment in 115/134 (85.8%) patients treated with clarithromycin and in 110/129 (85.3%) patients treated with amoxicillin-clavulanate. Adverse events were reported for 14.8% and 12.2% of patients for clarithromycin and amoxicillin-clavulanate, respectively. In this study clarithromycin was as effective and well tolerated as amoxicillin-clavulanate acid in the treatment of acute maxillary sinusitis.
Assuntos
Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Ácidos Clavulânicos/uso terapêutico , Sinusite Maxilar/tratamento farmacológico , Penicilinas/uso terapêutico , Doença Aguda , Adulto , Ácido Clavulânico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Sinusite Maxilar/microbiologia , Pessoa de Meia-IdadeRESUMO
In 1986, our institution published the first results of surgical résection of hepatocarcinoma in cirrhotic patients. The aim of this paper is to present long term results of this surgical management. From April 1978 to February 1992, 74 patients were operated on at the surgical clinic of University Medical Center of Rennes (35000) France. There were 60 hepatectomies and 14 transplantations. The mean age was 60.2 years-9 years and the sex ratio: 70 males and 4 females. The etiology was alcoholic in 43 patients (58%), post hepatitis (B and C) in 22 patients (30%) and due to hemochromatosis in 9 patients (12%). According to the Child Pugh classification, 48 patients were Child A, 11 Child B and one Child C in the hepatectomy group and 9 patients Child A and 5 Child B in transplantation group. The operative mortality was 10% in hepatectomy group and 35.7% in liver transplantation group. Overall survival was 61.8% at 1 year, 47.1% at 2 years, 38.2% at 3 years and 20% at 5 years. 5 year survival is 21.4% after transplantation and 18.5% after resection. This difference is not significant. In conclusion, according to 5 years survival and to operative mortality the treatment of choice is hepatectomy in HCC in cirrhotic patients. However the best treatment is the prevention of cirrhosis.
Assuntos
Carcinoma Hepatocelular/cirurgia , Cirrose Hepática/complicações , Neoplasias Hepáticas/cirurgia , Análise Atuarial , Carcinoma Hepatocelular/complicações , Feminino , Hemocromatose/complicações , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Hepatite B/complicações , Hepatite C/complicações , Humanos , Cirrose Hepática/cirurgia , Cirrose Hepática Alcoólica/complicações , Neoplasias Hepáticas/complicações , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de SobrevidaRESUMO
OBJECTIVE: Erythromycin, a macrolide antibiotic, has been reported to increase gastric emptying. The aim of this study was to evaluate the effects of intravenous erythromycin (150 mg/h) on gastric emptying, small intestinal transit time, gastric and biliopancreatic secretions during gastric infusion of a liquid diet in healthy volunteers. DESIGN: A randomized double-blind crossover study (erythromycin versus placebo). METHODS: Gastric emptying rates of nutrients, gastric acid secretion, gastric pH, jejunal flow rates, as well as biliopancreatic secretions and duodeno-caecal transit time, were evaluated during a continuous infusion at 4.5 kcal/min of a nutrient solution (1 kcal/ml) in the antrum, over a 6 h period, by a perfusion method. RESULTS: During the 6 h period, total gastric volume and gastric acid secretion decreased during erythromycin administration of 37 and 22%, respectively (area under the curves). Lipase outputs were significantly higher with erythromycin than placebo. Bile salt output was not significantly different between erythromycin and placebo. Duodeno-caecal transit time increased significantly during erythromycin infusion compared with placebo (191 +/- 12 versus 159 +/- 17 min; P < 0.05). CONCLUSION: During continuous gastric infusion of a liquid diet, intravenous erythromycin has a powerful effect on gastrointestinal function. The motor and secretory effects may enhance the tolerance and the efficiency of enteral nutrition in humans.
Assuntos
Antibacterianos/farmacologia , Ácidos e Sais Biliares/metabolismo , Nutrição Enteral , Eritromicina/farmacologia , Ácido Gástrico/metabolismo , Esvaziamento Gástrico/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Lipase/metabolismo , Adulto , Método Duplo-Cego , Alimentos Formulados , Humanos , Infusões Intravenosas , Intubação Gastrointestinal , MasculinoRESUMO
In 1986, our institution published the first results of surgical resection of hepatocarcinoma in cirrhotic patients. The aim of this paper is to present long term results of this surgical management. From April 1978 to February 1992, 74 patients were operated on at the surgical clinic of University Medical Center of Rennes (35000) France. There were 60 hepatectomies and 14 transplantations. The mean age was 60.2 years +/- 9 years and the sex ratio: 70 males and 4 females. The etiology was alcoholic in 43 patients (58%), post hepatitis (B and C) in 22 patients (30%) and due to hemochromatosis in 9 patients (12%). According to the Child Pugh classification, 48 patients were Child A, 11 Child B and one Child C in the hepatectomy group and 9 patients Child A and 5 Child B in transplantation group. The operative mortality was 10% in hepatectomy group and 35.7% in liver transplantation group. Overall survival was 61.8% at 1 year, 47.1% at 2 years, 38.2% at 3 years and 20% at 5 years. 5 year survival is 21.4% after transplantation and 18.5% after resection. This difference is not significant. In conclusion, according to 5 years survival and to operative mortality the treatment of choice is hepatectomy in HCC in cirrhotic patients. However the best treatment is the prevention of cirrhosis.
Assuntos
Carcinoma Hepatocelular/cirurgia , Cirrose Hepática/complicações , Neoplasias Hepáticas/cirurgia , Idoso , Carcinoma Hepatocelular/etiologia , Feminino , Humanos , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-IdadeRESUMO
Mycobacterium avium complex infections, common in patients with AIDS as either pulmonary or disseminated disease, are infrequent in patients without AIDS. Participants were 45 HIV-negative patients with lung disease and positive sputum cultures for M avium; 10 had documented immunocompromise, and 24 had preexisting lung disease. Clarithromycin dosage was 500 to 2,000 mg daily (mean +/- SD = 1,633 +/- 432 mg). The drug was administered either alone (n = 14) or in combination with rifampin (n = 8), aminoglycoside (n = 1), quinolone (n = 10), clofazimine (n = 18), isoniazid (n = 5), ethambutol (n = 9), pyrazinamide (n = 1), or minocycline (n = 6). At 3 months, 36 patients among 39 bacteriologically assessed had negative sputum cultures, 3 had positive culture, 3 were dead, and 3 discontinued treatment. At the end of treatment, 32 patients remained negative, 7 were positive. The success rate was 15 of 22 (64%) in patients previously treated with antimycobacterial drugs for M avium disease and 17 of 23 (74%) in new patients. Adverse effects included mild hearing loss (n = 4), increase in liver enzyme levels (n = 5), and gastrointestinal pain (n = 10, two of whom had to stop treatment). Patients stopped treatment after 300 +/- 186 days due to side effects (3), death (4), or the patient's (5) or physician's decision (33). During the follow-up, one patient suffered a relapse with peripheral lymph nodes. A daily dose of 30 mg/kg of clarithromycin in the treatment of M avium infections appears to be effective and safe. Concomitant drug therapy should be assessed for its ability to prevent relapse.
Assuntos
Claritromicina/uso terapêutico , Soronegatividade para HIV , Pneumopatias/tratamento farmacológico , Pneumopatias/microbiologia , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Idoso , Claritromicina/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Pneumopatias/imunologia , Masculino , Pessoa de Meia-Idade , Infecção por Mycobacterium avium-intracellulare/imunologia , Estudos Prospectivos , Resultado do TratamentoRESUMO
Tuberculosis sore throat remains relatively rare, is very deceptive, especially in its pseudo-neoplasmic form, and difficult to diagnose at first examination. This should be kept in mind, because correct diagnosis avoids the consequences of diagnosing a malignant tumor.