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1.
Folia Morphol (Warsz) ; 81(3): 685-693, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34060645

RESUMO

BACKGROUND: Primary synovial chondromatosis (PSC) is a rare idiopathic pathology characterised by the formation of osseocartilaginous nodules within synovial joints, tendons, or bursae. The mineralisation pattern of PSC nodules is poorly understood and has yet to be investigated using elemental analysis. Mapping this pattern could elucidate the progression of the disease. MATERIALS AND METHODS: Primary synovial chondromatosis nodules discovered during dissection of a formalin fixed donor were analysed. Scanning electron microscopy paired with energy dispersive X-ray spectroscopy (SEM-EDS) was used to quantify calcium and phosphorus levels to distinguish mineralised components from cartilage, indicated by increased carbon and oxygen concentrations. RESULTS: Nine nodules with average dimensions 1.76 cm × 1.25 cm were identified in the semimembranosus bursa. SEM-EDS demonstrated increased calcium phosphate levels in nodular cores, while outer margins contained primarily carbon and oxygen. Quantification of these elements revealed nodular peripheries to contain 68.0% carbon, 30.2% oxygen, 0.8% calcium, and 1.0% phosphate, while cores were comprised of 38.1% carbon, 42.1% oxygen, 14.1% calcium, and 5.7% phosphate. CONCLUSIONS: Nodules were found to have mineralised cores embedded within a cartilaginous matrix. This pattern suggests disease progression is facilitated by endochondral ossification, opening the potential for new therapeutic techniques.


Assuntos
Condromatose Sinovial , Cálcio , Carbono , Condromatose Sinovial/patologia , Humanos , Oxigênio , Fosfatos
2.
Aust J Prim Health ; 28(1): 63-68, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34847988

RESUMO

Preconception care (PCC) entails counselling and interventions to optimise health before pregnancy. Barriers to this service delivery include access and time. Primary healthcare nurses (PHCNs) are uniquely placed to deliver PCC. The aim of this study was to understand PHCNs' knowledge, practice and attitudes to PCC. A cross-sectional study was performed of a convenience sample of PHCNs in Australia who were seeing people of reproductive age. Recruitment was via the Australian Primary Health Care Nurses Association (APNA) electronic communication platforms. The 18-item, online, anonymous survey captured demographics, as well as PCC knowledge, practices and attitudes. Descriptive statistics were used to describe our findings. In all, 152 completed surveys were received. Of all respondents, 74% stated they discuss PCC in their practice, although only 13% do so routinely. Of these, more preconception discussions are held with women than with men. In total, 95% of respondents identified at least one barrier to delivery of PCC, with lack of time and knowledge being the most common. The findings of this study can inform targeted strategies, including education programs and resources, and consideration of incentives to support PHCNs deliver PCC. This study identifies areas for improvement at the individual, organisational and health system levels to enhance the role of PHCNs in PCC.


Assuntos
Competência Clínica , Cuidado Pré-Concepcional , Austrália , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Gravidez , Atenção Primária à Saúde , Inquéritos e Questionários
3.
Psychooncology ; 22(3): 481-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22331643

RESUMO

BACKGROUND: Cancer clinical trials (CCTs) are important tools in the development of improved cancer therapies; yet, participation is low. Key psychosocial barriers exist that appear to impact a patient's decision to participate. Little is known about the relationship among knowledge, self-efficacy, preparation, decisional conflict, and patient decisions to take part in CCTs. OBJECTIVE: The purpose of this study was to determine if preparation for consideration of a CCT as a treatment option mediates the relationship between knowledge, self-efficacy, and decisional conflict. We also explored whether lower levels of decisional conflict are associated with greater likelihood of CCT enrollment. METHOD: In a pre-post test intervention study, cancer patients (N = 105) were recruited before their initial consultation with a medical oncologist. A brief educational intervention was provided for all patients. Patient self-report survey responses assessed knowledge, self-efficacy, preparation for clinical trial participation, decisional conflict, and clinical trial participation. RESULTS: Preparation was found to mediate the relationship between self-efficacy and decisional conflict (p = 0.003 for a test of the indirect mediational pathway for the decisional conflict total score). Preparation had a more limited role in mediating the effect of knowledge on decisional conflict. Further, preliminary evidence indicated that reduced decisional conflict was associated with increased clinical trial enrollment (p = 0.049). CONCLUSIONS: When patients feel greater CCT self-efficacy and have more knowledge, they feel more prepared to make a CCT decision. Reduced decisional conflict, in turn, is associated with the decision to enroll in a clinical trial. Our results suggest that preparation for decision-making should be a target of future interventions to improve participation in CCTs.


Assuntos
Ensaios Clínicos como Assunto/psicologia , Conflito Psicológico , Tomada de Decisões , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/terapia , Autoeficácia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Educação de Pacientes como Assunto/métodos , Seleção de Pacientes
4.
Mol Psychiatry ; 16(8): 818-25, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21483434

RESUMO

Positive emotionality (PEM) (personality construct of well-being, achievement/motivation, social and closeness) has been associated with striatal dopamine D2 receptor availability in healthy controls. As striatal D2 receptors modulate activity in orbitofrontal cortex (OFC) and cingulate (brain regions that process natural and drug rewards), we hypothesized that these regions underlie PEM. To test this, we assessed the correlation between baseline brain glucose metabolism (measured with positron emission tomography and [(18)F]fluoro-deoxyglucose) and scores on PEM (obtained from the multidimensional personality questionnaire or MPQ) in healthy controls (n = 47). Statistical parametric mapping (SPM) analyses revealed that PEM was positively correlated (P(c)<0.05, voxel corrected) with metabolism in various cortical regions that included orbitofrontal (Brodman area, BA 11, 47) and cingulate (BA 23, 32) and other frontal (BA 10, 9), parietal (precuneus, BA 40) and temporal (BA 20, 21) regions that overlap with the brain's default mode network (DMN). Correlations with the other two main MPQ personality dimensions (negative emotionality and constraint) were not significant (SPM P(c)<0.05). Our results corroborate an involvement of orbitofrontal and cingulate regions in PEM, which is considered a trait that protects against substance use disorders. As dysfunction of OFC and cingulate is a hallmark of addiction, these findings support a common neural basis underlying protective personality factors and brain dysfunction underlying substance use disorders. In addition, we also uncovered an association between PEM and baseline metabolism in regions from the DMN, which suggests that PEM may relate to global cortical processes that are active during resting conditions (introspection, mind wandering).


Assuntos
Mapeamento Encefálico/psicologia , Emoções/fisiologia , Lobo Frontal/fisiologia , Giro do Cíngulo/fisiologia , Vias Neurais/fisiologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Lobo Frontal/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Vias Neurais/diagnóstico por imagem , Inventário de Personalidade , Cintilografia
5.
Cases J ; 2: 7995, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19830040

RESUMO

X-linked adrenoleukodystrophy is an X-linked recessive disorder affecting approximately 1 in 21,000 males, and is estimated to be the cause of adrenal insufficiency in approximately 35% of patients with idiopathic Addison's disease. The disease is caused by defective beta-oxidation of fatty acids in peroxisomes that leads to elevated serum concentrations of very-long-chain saturated fatty acids. The accumulation causes a primary adrenal insufficiency and progressive neurological dysfunction. This article presents a case of X-linked adrenoleukodystrophy in its milder form, adrenomyeloneuropathy.

6.
HIV Med ; 10(2): 116-24, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19200175

RESUMO

BACKGROUND: This phase IIb study explored the antiviral activity and safety of the investigational CC chemokine receptor 5 (CCR5) antagonist aplaviroc (APL) in antiretroviral-naïve patients harbouring R5- or R5X4-tropic virus. METHODS: A total of 191 patients were randomized 2:2:2:1 to one of three APL dosing regimens or to lamivudine (3TC)/zidovudine (ZDV) twice daily (bid), each in combination with lopinavir/ritonavir (LPV/r) 400 mg/100 mg bid. Efficacy, safety and pharmacokinetic parameters were assessed. RESULTS: This study was terminated prematurely because of APL-associated idiosyncratic hepatotoxicity. A total of 141 patients initiated treatment early enough to have been able to complete 12 weeks on treatment [modified intent-to-treat (M-ITT) population]; of these, 133 completed the 12-week treatment phase. The proportion of subjects in the M-ITT population with HIV-1 RNA <400 copies/mL at week 12 was 50, 48, 54 and 75% in the APL 200 mg bid, APL 400 mg bid, APL 800 mg once a day (qd) and 3TC/ZDV arms, respectively. Similar responses were seen in the few subjects harbouring R5X4-tropic virus (n=17). Common clinical adverse events (AEs) were diarrhoea, nausea, fatigue and headache. APL demonstrated nonlinear pharmacokinetics with high interpatient variability. CONCLUSIONS: While target plasma concentrations of APL were achieved, the antiviral activity of APL+LPV/r did not appear to be comparable to that of 3TC/ZDV+LPV/r.


Assuntos
Benzoatos/toxicidade , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1 , Piperazinas/toxicidade , Pirimidinonas/uso terapêutico , Ritonavir/uso terapêutico , Compostos de Espiro/toxicidade , Adulto , Idoso , Benzoatos/farmacocinética , Dicetopiperazinas , Esquema de Medicação , Quimioterapia Combinada , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Inibidores da Protease de HIV/farmacocinética , HIV-1/imunologia , Humanos , Lopinavir , Masculino , Pessoa de Meia-Idade , Piperazinas/farmacocinética , Pirimidinonas/farmacocinética , RNA Viral/imunologia , Receptores CCR5/uso terapêutico , Ritonavir/farmacocinética , Compostos de Espiro/farmacocinética , Adulto Jovem
7.
Arch Oral Biol ; 54(2): 185-91, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18980757

RESUMO

OBJECTIVE: Vascular endothelial growth factor (VEGF) has been implicated in the regulation of dental pulp and dentine repair. Therapeutic ultrasound was shown to be effective for fracture repair. We investigated whether low frequency ultrasound influences the production of VEGF by odontoblast-like cells. Moreover, we examined the direct effects of VEGF on odontoblast-like cell proliferation. DESIGN: MDPC-23, an established odontoblast-like cell line, was exposed to increasing intensities of 30kHz ultrasound using an ultrasonic tip probe. RESULTS: After 24h cell culture, WST-1 analysis of cell viability and number showed a dose-dependent decrease in the number of viable cells with increasing ultrasound power. However, the relative concentration of VEGF as analysed by ELISA and normalised to cell number was significantly increased in the culture supernatants indicating an ultrasound-induced stimulation of odontoblastic VEGF secretion. Analysis of VEGF gene expression by sqRT-PCR revealed the expression of the main VEGF isoforms in the MDPC-23 cells, i.e. VEGF(120) and VEGF(164) as well as to a minor extent VEGF(188). Low power ultrasound increased gene expression of all VEGF isoforms. Addition of recombinant VEGF to the cell cultures significantly stimulated cell proliferation. Gene expression of the VEGF receptors Flt1/VEGFR1 and KDR/VEGFR2 was detected in the MDPC-23, suggesting the possibility that VEGF may act on the odontoblast-like cells in an autocrine manner. CONCLUSIONS: Our results indicate that ultrasound promoted VEGF expression and production by odontoblast-like cells and that VEGF may have autocrine effects on these cells. It is proposed that ultrasound may influence odontoblast activity and dentine repair by modulating production of endogenous growth factors in the dentine-pulp complex.


Assuntos
Odontoblastos/metabolismo , Terapia por Ultrassom , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica , Camundongos , Odontoblastos/citologia , Odontoblastos/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/farmacologia
8.
Appl Opt ; 47(22): 4085-93, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18670566

RESUMO

When lidar pulses travel through a short path that includes a relatively high concentration of aerosols, scattering phenomena can alter the power and temporal properties of the pulses significantly, causing undesirable effects in the received pulse. In many applications the design of the lidar transmitter and receiver must consider adverse environmental aerosol conditions to ensure the desired performance. We present an analytical model of lidar system operation when the optical path includes aerosols for use in support of instrument design, simulations, and system evaluation. The model considers an optical path terminated with a solid object, although it can also be applied, with minor modifications, to cases where the expected backscatter occurs from nonsolid objects. The optical path aerosols are characterized by their attenuation and backscatter coefficients derived by the Mie theory from the concentration and particle size distribution of the aerosol. Other inputs include the lidar system parameters and instrument response function, and the model output is the time-resolved received pulse. The model is demonstrated and experimentally validated with military fog oil smoke for short ranges (several meters). The results are obtained with a lidar system operating at a wavelength of 0.905 microm within and outside the aerosol. The model goodness of fit is evaluated using the statistical coefficient of determination whose value ranged from 0.88 to 0.99 in this study.


Assuntos
Aerossóis/análise , Aerossóis/química , Algoritmos , Artefatos , Lasers , Modelos Teóricos , Radar , Simulação por Computador , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade
9.
Antimicrob Agents Chemother ; 52(3): 858-65, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18070967

RESUMO

Aplaviroc (APL) was a new CCR5 antagonist that was investigated in two dose-ranging studies with antiretroviral therapy-naïve, human immunodeficiency virus-infected adults: ASCENT, in which 147 subjects were randomized 2:2:1 to receive zidovudine-lamivudine (ZDV-3TC) plus APL 600 mg twice a day (BID), APL 800 mg BID, or efavirenz (EFV), respectively, and EPIC, in which 195 subjects were randomized 2:2:2:1 to receive lopinavir-ritonavir (LPV-RTV) plus APL 200 mg BID, APL 400 mg BID, APL 800 mg once a day, or ZDV-3TC BID, respectively. Both studies (and, ultimately, the clinical development of APL) were discontinued after a mean of 14 weeks of therapy because of higher than anticipated severe liver toxicity; grade 2 or higher treatment-emergent elevations in alanine aminotransferase (ALT) levels were observed in 17/281 (6.0%) APL recipients but only 2/55 (3.6%) control recipients, while grade 2 or higher elevations in total bilirubin levels occurred in 29/281 (10.3%) APL recipients but only 4/55 (7.3%) controls. Two APL recipients developed grade 3 or higher treatment-emergent elevations in both ALT and total bilirubin levels, and one of these individuals had a severe case of hepatic cytolysis that was attributed to APL. Despite the high intersubject variability in APL plasma exposures, a Pearson correlation analysis of the combined study data did not reveal any significant associations between plasma concentrations and the liver enzyme elevations observed during the study. The mechanism for the idiosyncratic hepatotoxicity observed in the clinical trials of APL is unknown but is likely intrinsic to the molecule rather than its novel mechanism of action.


Assuntos
Benzoatos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas , Inibidores da Fusão de HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Piperazinas/efeitos adversos , Compostos de Espiro/efeitos adversos , Adulto , Alanina Transaminase/sangue , Benzoatos/administração & dosagem , Benzoatos/farmacocinética , Benzoatos/farmacologia , Bilirrubina/sangue , Dicetopiperazinas , Método Duplo-Cego , Feminino , Inibidores da Fusão de HIV/administração & dosagem , Inibidores da Fusão de HIV/farmacocinética , Inibidores da Fusão de HIV/farmacologia , Infecções por HIV/virologia , Humanos , Fígado/efeitos dos fármacos , Masculino , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Piperazinas/farmacologia , Compostos de Espiro/administração & dosagem , Compostos de Espiro/farmacocinética , Compostos de Espiro/farmacologia
10.
Clin Exp Immunol ; 148(2): 307-24, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17355248

RESUMO

To investigate the molecular effects of the periodontopathogens Fusobacterium nucleatum (FN) and Porphyromonas gingivalis (PG) on the oral epithelium, the H400 oral epithelial cell line was cultured in the presence of non-viable bacteria. Following confirmation of the presence of transcripts for the bacterial pattern recognition receptors in H400 cells, Toll-like receptors -2, -4 and -9, and components of the NF-kappaB signalling pathway, immunocytochemical analyses were performed showing that NF-kappaB was activated within 1 h of exposure to both periodontopathogens. A significantly greater number of NF-kappaB nuclear translocations were apparent following H400 cell exposure to FN as compared with PG. Gene expression analyses indicated that transcripts known to be regulated by the NF-kappaB pathway, including cytokines/chemokines TNF-alpha, IL-1beta, IL-8, MCP-1/CCL2 and GM-CSF, were up-regulated following 4 and 24 h of exposure to both periodontopathogens. In addition, H400 periodontopathogen exposure resulted in differential regulation of transcripts for several cytokeratin gene family members. Consistent with the immunocytochemical data, microarray results indicated that FN induced a greater number of gene expression changes than PG following 24 h of exposure, 609 and 409 genes, respectively. Ninety-one genes were commonly differentially expressed by both periodontopathogens and represented biological processes commonly associated with periodontitis. Gene expression analyses by reserve transcriptase-polymerase chain reaction (RT-PCR) of molecules identified from the microarray data sets, including Heme oxygenase-1, lysyl oxidase, SOD2, CCL20 and calprotectin components, confirmed their differential expression profiles induced by the two periodontopathogens. FN and PG have clearly different molecular effects on oral epithelial cells, potentially highlighting the importance of the composition of the plaque biofilm in periodontitis pathogenesis.


Assuntos
Mucosa Bucal/metabolismo , NF-kappa B/metabolismo , Periodontite/metabolismo , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/patologia , Linhagem Celular , Quimiocinas/biossíntese , Quimiocinas/genética , Células Epiteliais/metabolismo , Infecções por Fusobacterium/metabolismo , Infecções por Fusobacterium/patologia , Fusobacterium nucleatum , Regulação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Periodontite/genética , Periodontite/microbiologia , Periodontite/patologia , Porphyromonas gingivalis , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transdução de Sinais , Regulação para Cima
12.
Biochimie ; 86(6): 419-23, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15358058

RESUMO

The diepoxide mycotoxin (2R, 3R, 8R, 9R)-4,6-decadiyne-2,3:8,9-diepoxy-1,10-diol (repandiol) was both isolated from the mushroom Hydnum repandum and synthesized de novo. Repandiol was found to form interstrand cross-links within a restriction fragment of DNA, linking deoxyguanosines on opposite strands primarily within the 5'-GNC and 5'-GNNC sequences preferred by diepoxyoctane. However, repandiol was a significantly less efficient cross-linker than either of the diepoxyalkanes (diepoxyoctane and diepoxybutane) to which it was compared.


Assuntos
Alcinos/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Citotoxinas/farmacologia , DNA/química , Compostos de Epóxi/farmacologia , Alcinos/química , Alcinos/isolamento & purificação , Sequência de Bases , Reagentes de Ligações Cruzadas/química , Citotoxinas/química , DNA/efeitos dos fármacos , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Dados de Sequência Molecular , Piperidinas/química , Relação Estrutura-Atividade
13.
ISA Trans ; 43(1): 153-68, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15000144

RESUMO

Multivariable optimization (MVO) is a powerful nonlinear steady-state flowsheet simulation technique used widely in the chemical process industry to optimize plant performance by increasing plant capacity and/or reducing energy usage. The user supplies the objective function(s), constraints, and variable limits based on operating heuristics, prior experience, and observed process behavior. In this paper we describe how we used MVO in conjunction with improved automation and statistical process monitoring to increase capacity and reduce energy consumption. This project was conducted over a two-year period in a methylamines facility that produces three products: monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA). It led to a 14% improvement in MMA capacity and a 7% improvement in TMA capacity. Energy consumption per pound of main product decreased by approximately 20% for the six-month period (April-September, 2000) when compared to a three-year average (1997-2000). It was accompanied by a 60% improvement in process capability and 31% improvement in product quality. We attribute this improvement to several factors: smoother transition between optimum set points determined by the process optimizer, improved disturbance rejection due to controller installation and tuning, and reduced operator intervention because of controlled operation at or near the optimum set points.


Assuntos
Algoritmos , Indústria Química/métodos , Técnicas de Química Combinatória , Retroalimentação , Modelos Químicos , Análise Multivariada , Sistemas On-Line , Metilaminas/síntese química , Modelos Estatísticos , Controle de Qualidade
14.
Mol Pathol ; 56(5): 270-4, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14514920

RESUMO

AIMS: The lung is one of the major sites of phase I cytochrome P450 enzyme and phase II sulfotransferase expression, which together are thought to act as an enzymic barrier against the unimpeded transfer of airborne xenobiotics into the lung parenchyma and systemic circulation. Sulfate for conjugation is produced primarily from the oxidation of cysteine, begun by cysteine dioxygenase (CDO), and completed with the conversion of sulfite to sulfate via sulfite oxidase (SO). Little is known about the site of expression of these two enzymes in the alveoli of the human lung. METHODS: Antibodies and oligonucleotide probes raised against both CDO and SO were used for immunohistochemistry and in situ hybridisation, respectively, to investigate the expression of CDO and SO in human lung alveoli. RESULTS: CDO and SO were expressed in alveolar epithelial cells, which is also the site of expression of cytochrome P450 1B1. CONCLUSIONS: These results demonstrate that the two key enzymes in sulfate production are expressed in the same locale as phase I and phase II enzymes, and that these two enzymes may be involved in the production of sulfate for the maintenance of a metabolic barrier against the entry of airborne xenobiotics and the synthesis of important structural proteins and proteoglycans.


Assuntos
Dioxigenases , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Oxigenases/metabolismo , Alvéolos Pulmonares/enzimologia , Xenobióticos/farmacocinética , Poluentes Atmosféricos/farmacocinética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Cisteína Dioxigenase , Citocromo P-450 CYP1B1 , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Humanos , Técnicas Imunoenzimáticas , Inativação Metabólica/fisiologia , Masculino , Pessoa de Meia-Idade , Alvéolos Pulmonares/metabolismo , Sulfatos/metabolismo
15.
Antivir Ther ; 6(2): 89-96, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11491421

RESUMO

OBJECTIVE: To evaluate the antiretroviral activity and safety of multiple escalating doses of amprenavir administered alone, and in combination with abacavir in HIV-1-infected adults. DESIGN: Sixty-two HIV-1-infected subjects were enrolled in a multicentre, open-label, non-randomized, dose-escalating trial. METHODS: Subjects were assigned to one of six dose groups and received amprenavir 300 mg twice daily, 300 mg three times daily, 900, 1050, or 1,200 mg twice daily for 4 weeks. One dose group received amprenavir 900 mg twice daily in combination with abacavir 300 mg twice daily for 4 weeks. Antiretroviral activity was assessed by measuring changes from baseline in plasma HIV-1 RNA levels and CD4 cell counts. Safety was evaluated by monitoring clinical adverse events and changes in laboratory values. Genotypic and phenotypic analyses were performed using ABI sequencing and the recombinant virus assay, respectively. RESULTS: At week 4, amprenavir monotherapy (900, 1,050, or 1,200 mg twice daily) resulted in marked decreases in plasma HIV-1 RNA levels (1.3-1.6 log10 copies/ml), and substantial increases in CD4 cell counts in the two dose groups who received 1,050 mg twice daily (118 x 10(6) cells/mm3) or 1,200 mg twice daily (114 x 10(6) cells/mm3). Amprenavir/abacavir resulted in median plasma HIV-1 RNA reductions of 1.8 log10 copies/ml, and median CD4 cell count increases of 138 x 10(6) cells/mm3. Amprenavir was reasonably well tolerated with few treatment-limiting adverse events. No known active site mutations associated with amprenavir resistance were selected in any of the dose groups, and no significant phenotypic resistance to amprenavir developed during 4 weeks of therapy. CONCLUSIONS: The antiviral effect of amprenavir monotherapy increased with escalating doses, and all amprenavir doses were reasonably well tolerated over 4 weeks of therapy. Amprenavir/abacavir combination therapy elicited a potent antiviral effect. The three highest doses of amprenavir (900, 1,050 and 1,200 mg twice daily) were selected to design subsequent Phase II and III studies that confirmed the safety profile and efficacy of amprenavir in combination regimens and led to the approval of amprenavir in the USA in 1999.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/administração & dosagem , HIV-1/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Administração Oral , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Carbamatos , Didesoxinucleosídeos/administração & dosagem , Didesoxinucleosídeos/efeitos adversos , Didesoxinucleosídeos/farmacologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Furanos , Genótipo , Infecções por HIV/sangue , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Masculino , Dose Máxima Tolerável , Fenótipo , Sulfonamidas/efeitos adversos , Sulfonamidas/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
16.
Biochemistry ; 40(35): 10677-85, 2001 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-11524013

RESUMO

Diepoxyalkanes form interstrand cross-links in DNA oligomers preferentially at 5'-GNC sites. We have examined cross-linking by 1,2,3,4-diepoxybutane (DEB) and 1,2,7,8-diepoxyoctane (DEO) within a fragment of the 5S RNA gene of Xenopus borealis in both the free and nucleosomal states. Sites and efficiencies of interstrand cross-linking were probed through denaturing polyacrylamide gel electrophoresis and quantitative phosphorimagery. Both agents targeted 5'-GNC sites for cross-linking in the restriction fragment in its free state, and DEO also targeted 5'-GNNC sites. Monoalkylation occurred at all deoxyguanosines. The sites for both monoalkylation and interstrand cross-linking were similar in nucleosomal and free DNA, and cross-linked DNA was cleanly incorporated into the core particle structure. These findings suggest that the 5S core particle is able to tolerate any structural abnormalities induced by diepoxide cross-linking.


Assuntos
DNA/química , Compostos de Epóxi/química , Animais , Sequência de Bases , Galinhas , Reagentes de Ligações Cruzadas , Dados de Sequência Molecular , RNA Ribossômico 5S/química , Xenopus
17.
J Acquir Immune Defic Syndr ; 26(5): 458-61, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11391165

RESUMO

This study evaluated dual protease inhibitor (PI) regimens containing amprenavir (APV) in PI-naive, HIV-1-infected patients over 48 weeks. Patients were randomized to 800-mg APV combined with 800-mg indinavir (IDV), 750-mg nelfinavir (NFV), or 800-mg saquinavir-soft gel capsule (SGV-SGC), all three times daily without nucleoside reverse transcriptase inhibitors, or APV given alone for 3 weeks and then with 150-mg lamivudine (3TC) and 300-mg zidovudine (ZDV), twice daily. Dual PI therapy demonstrated substantial antiviral activity and was generally safe and well tolerated. Eight patients had virologic failure; 5 were receiving dual PI therapy and 3 were in the APV/3TC/ZDV arm. The protease I50V mutation characteristic of APV resistance was not observed, although other key PI mutations were selected in 4 patients failing therapy, 2 of whom had PI resistance at baseline.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1/fisiologia , Sulfonamidas/uso terapêutico , Adulto , Idoso , Carbamatos , Quimioterapia Combinada , Feminino , Furanos , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , RNA Viral/sangue , Inibidores da Transcriptase Reversa/uso terapêutico , Resultado do Tratamento
18.
Med Phys ; 27(11): 2594-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11128312

RESUMO

Our purpose in this study was (i) to measure trabecular bone structure using fractal analysis of distal radius radiographs in subjects with and without osteoporotic hip fractures, and (ii) to compare these measures with bone mineral density (BMD) as well as with measures of trabecular bone structure derived from high resolution magnetic resonance (MR) images. Distal radius radiographs were obtained using semi-industrial films (55 kVp, 400 mAs) in 30 postmenopausal patients, who had suffered osteoporotic hip fractures (74.8+/-8.2 years) in the last 24 months and 27 postmenopausal age-matched (74.6+/-6.6 yr) normal volunteers. Radiographs were digitized at 50 microm. A Fourier power spectrum-based fractal dimension (FD) characterizing the trabecular pattern was measured in a region of interest proximal to the joint line. The fractal dimension was calculated over two spatial frequency (f) ranges: FD1 was calculated over 0.5

Assuntos
Osso e Ossos/diagnóstico por imagem , Fractais , Idoso , Densidade Óssea , Estudos de Casos e Controles , Feminino , Fêmur/diagnóstico por imagem , Quadril/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Estatísticos , Osteoporose/diagnóstico por imagem , Pós-Menopausa , Curva ROC , Radiografia
19.
Biochemistry ; 39(51): 16046-55, 2000 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-11123932

RESUMO

Interstrand cross-linking studies with the antitumor drug cis-diamminedichloroplatinum(II) and its clinically inactive isomer, trans-diamminedichloroplatinum(II), were performed on a fragment of the 5S rRNA gene of Xenopus borealis in the free and nucleosomal state. 5S nucleosomes were formed via histone octamer exchange from chicken erythrocyte core particles. Native polyacrylamide gel electrophoresis was used to probe the ability of platinated DNA to reconstitute into core particles. Both isomers negatively impacted reconstitution when histones were present during incubation with the drug. When histones were not present during the drug treatment, platinated DNA was successfully reconstituted into core particles. These results suggest that platination of histones impedes reconstitution of free DNA. However, already-formed core particles were not disrupted upon platination. Sites of interstrand cross-linking were probed through denaturing polyacrylamide gel electrophoresis and quantitative phosphorimagery. We found both site-specific enhancement and depression of cis-diamminedichloroplatinum(II) cross-linking in the nucleosomal samples relative to free DNA at both drug concentrations that were tested (0.01 and 0.0025 mM). trans-Diamminedichloroplatinum(II) exhibited no detectable differences in the interstrand cross-linking of free and nucleosomal samples.


Assuntos
Cisplatino/metabolismo , Reagentes de Ligações Cruzadas/metabolismo , DNA/metabolismo , Nucleossomos/metabolismo , Animais , Autorradiografia , Sequência de Bases , Galinhas , Cisplatino/química , Reagentes de Ligações Cruzadas/química , DNA/química , DNA Ribossômico/química , Eritrócitos/metabolismo , Histonas/química , Hidrólise , Radical Hidroxila/química , Dados de Sequência Molecular , Nucleossomos/química , Nucleossomos/genética , RNA Ribossômico 5S/química , RNA Ribossômico 5S/genética , Estereoisomerismo , Xenopus/genética
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