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1.
ESMO Open ; 7(2): 100416, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35248823

RESUMO

BACKGROUND: Guidelines recommend neoadjuvant chemotherapy (NAC) for the treatment of nonmetastatic muscle-invasive bladder cancer (MIBC). NAC is, however, underutilized in practice because of its associated limited overall survival (OS) benefit and significant treatment-related toxicity. We hypothesized that the absence of circulating tumour cells (CTCs) identifies MIBC patients with such a favourable prognosis that NAC may be withheld. PATIENTS AND METHODS: The CirGuidance study was an open-label, multicentre trial that included patients with clinical stage T2-T4aN0-N1M0 MIBC, scheduled for radical cystectomy. CTC-negative patients (no CTCs detectable using the CELLSEARCH system) underwent radical surgery without NAC; CTC-positive patients (≥1 detectable CTCs) were advised to receive NAC, followed by radical surgery. The primary endpoint was the 2-year OS in the CTC-negative group with a prespecified criterion for trial success of ≥75% (95% confidence interval (CI) ±5%). RESULTS: A total of 273 patients were enrolled. Median age was 69 years; median follow-up was 36 months. The primary endpoint of 2-year OS in the CTC-negative group was 69.5% (N = 203; 95% CI 62.6%-75.5%). Two-year OS was 58.2% in the CTC-positive group (N = 70; 95% CI 45.5%-68.9%). CTC-positive patients had a higher rate of cancer-related mortality [hazard ratio (HR) 1.61, 95% CI 1.05-2.45, P = 0.03] and disease relapse (HR 1.87, 95% CI 1.28-2.73, P = 0.001) than CTC-negative patients. Explorative analyses suggested that CTC-positive patients who had received NAC (n = 22) survived longer than CTC-positive patients who had not (n = 48). CONCLUSION: The absence of CTCs in MIBC patients was associated with improved cancer-related mortality and a lower risk of disease relapse after cystectomy; however, their absence alone does not justify to withhold NAC. Exploratory analyses suggested that CTC-positive MIBC patients might derive more benefit from NAC. TRIAL REGISTRATION: Netherlands Trial Register NL3954; https://www.trialregister.nl/trial/3954.


Assuntos
Células Neoplásicas Circulantes , Neoplasias da Bexiga Urinária , Idoso , Feminino , Humanos , Masculino , Músculos/patologia , Terapia Neoadjuvante , Recidiva , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia
2.
Geroscience ; 43(1): 239-252, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33034792

RESUMO

We assessed whether objectively measured low- and high-intensity physical activity (LPA and HPA) and sedentary time (ST) were associated with white matter connectivity, both throughout the whole brain and in brain regions involved in motor function. In the large population-based Maastricht Study (n = 1715, age 59.6 ± 8.1 (mean ± standard deviation) years, and 48% women), the amounts of LPA, HPA, and ST were objectively measured during 7 days by an activPAL accelerometer. In addition, using 3T structural and diffusion MRI, we calculated whole brain node degree and node degree of the basal ganglia and primary motor cortex. Multivariable linear regression analysis was performed, and we report standardized regression coefficients (stß) adjusted for age, sex, education level, wake time, diabetes status, BMI, office systolic blood pressure, antihypertensive medication, total-cholesterol-to-HDL-cholesterol ratio, lipid-modifying medication, alcohol use, smoking status, and history of cardiovascular disease. Lower HPA was associated with lower whole brain node degree after full adjustment (stß [95%CI] = - 0.062 [- 0.101, - 0.013]; p = 0.014), whereas lower LPA (stß [95%CI] = - 0.013 [- 0.061, 0.034]; p = 0.580) and higher ST (stß [95%CI] = - 0.030 [- 0.081, 0.021]; p = 0.250) was not. In addition, lower HPA was associated with lower node degree of the basal ganglia after full adjustment (stß [95%CI] = - 0.070 [- 0.121, - 0.018]; p = 0.009). Objectively measured lower HPA, but not lower LPA and higher ST, was associated with lower whole brain node degree and node degree in specific brain regions highly specialized in motor function. Further research is needed to establish whether more HPA may preserve structural brain connectivity.


Assuntos
Doenças Cardiovasculares , Substância Branca , Idoso , Encéfalo/diagnóstico por imagem , Exercício Físico , Feminino , Humanos , Masculino , Comportamento Sedentário , Substância Branca/diagnóstico por imagem
3.
Neth Heart J ; 29(3): 172, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33252706
5.
Bone ; 127: 510-516, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31226529

RESUMO

Identifying determinants of long-term functional outcome after a distal radius fracture is challenging. Previously, we reported on the association between early HR-pQCT measurements and clinical outcome 12 weeks after a conservatively treated distal radius fracture. We extended the follow-up and assessed functional outcome after two years in relation to early HR-pQCT derived bone parameters. HR-pQCT scans of the fracture region were performed in 15 postmenopausal women with a distal radius fracture at 1-2 (baseline), 3-4 weeks and 26 months post-fracture. Additionally, the contralateral distal radius was scanned at baseline. Bone density, micro-architecture parameters and bone stiffness using micro-finite element analysis (µFEA) were evaluated. During all visits, wrist pain and function were assessed using the patient-rated wrist evaluation questionnaire (PRWE), quantifying functional outcome with a score between 0 and 100. Two-year PRWE was associated with torsional and bending stiffness 3-4 weeks post-fracture (R2: 0.49, p = 0.006 and R2: 0.54, p = 0.003, respectively). In contrast, early micro-architecture parameters of the fracture region or contralateral bone parameters did not show any association with long-term outcome. This exploratory study indicates that HR-pQCT with µFEA performed within four weeks after a distal radius fracture captures biomechanical fracture characteristics that are associated with long-term functional outcome and therefore could be a valuable early outcome measure in clinical trials and clinical practice.


Assuntos
Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/fisiopatologia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Tomografia Computadorizada por Raios X , Idoso , Fenômenos Biomecânicos , Avaliação da Deficiência , Feminino , Humanos , Pessoa de Meia-Idade , Dor/etiologia , Fraturas do Rádio/complicações , Fatores de Tempo
6.
Osteoporos Int ; 29(12): 2725-2738, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30209523

RESUMO

In this small cross-sectional study of predominantly well-treated participants with relatively short-term type 2 diabetes duration, HbA1c > 7% (53 mmol/mol) was associated with lower cortical density and thickness and higher cortical porosity at the distal radius, lower trabecular thickness at the distal tibia, and higher trabecular number at both sites. INTRODUCTION: To examine the association between diabetes status and volumetric bone mineral density (vBMD), bone microarchitecture and strength of the distal radius and tibia as assessed with HR-pQCT. Additionally-in participants with type 2 diabetes (T2DM), to examine the association between HbA1c, diabetes duration, and microvascular disease (MVD) and bone parameters. METHODS: Cross-sectional data from 410 (radius) and 198 (tibia) participants of The Maastricht Study (mean age 58 year, 51% female). Diabetes status (normal glucose metabolism, prediabetes, or T2DM) was based on an oral glucose tolerance test and medication history. RESULTS: After full adjustment, prediabetes and T2DM were not associated with vBMD, bone microarchitecture, and strength of the radius and tibia, except for lower trabecular number (Tb.N) of the tibia (- 4%) in prediabetes and smaller cross-sectional area of the tibia (- 7%) in T2DM. In T2DM, HbA1c > 7% was associated with lower cortical vBMD (- 5%), cortical thickness (- 16%), higher cortical porosity (+ 20%) and Tb.N (+ 9%) of the radius, and higher Tb.N (+ 9%) and lower trabecular thickness (- 13%) of the tibia. Diabetes duration > 5 years was associated with higher Tb.N (+ 6%) of the radius. The presence of MVD was not associated with any bone parameters. CONCLUSIONS: In this study with predominantly well-treated T2DM participants with relatively short-term diabetes duration, inadequate blood glucose control was negatively associated with cortical bone measures of the radius. In contrast, trabecular number was increased at both sites. Studies of larger sample size are warranted for more detailed investigations of bone density and bone quality in patients with T2DM.


Assuntos
Densidade Óssea/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hemoglobinas Glicadas/análise , Rádio (Anatomia)/fisiopatologia , Tíbia/fisiopatologia , Adulto , Idoso , Estudos Transversais , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/diagnóstico por imagem , Sistema de Registros , Tíbia/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios X
7.
Bone ; 101: 156-161, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28487133

RESUMO

Type 2 diabetes mellitus (T2DM) has been associated with an increased risk of fractures, despite normal to increased bone mineral density (BMD). Insulin use is one of the factors linked to this increased fracture risk. However, direct negative effects of insulin on bone quality are not expected since insulin is thought to be anabolic to bone. In this cross-sectional study the association between insulin use and volumetric BMD (vBMD), bone micro-architecture and bone strength of the distal radius, as measured with HR-pQCT, was examined. Data from 50 participants with T2DM of The Maastricht Study (mean age 62±7.5years, 44% women) was used. Participants were classified as insulin user (n=13) or non-insulin user (n=37) based on prescription data. Linear regression analysis was used to estimate the association between current insulin use and HR-pQCT derived parameters. After adjustment for age, sex, body mass index, glycated hemoglobin A1c and T2DM duration, insulin use was associated with lower total vBMD (standardized beta (ß):-0.56 (95% CI:-0.89 to -0.24)), trabecular vBMD (ß:-0.58 (95% CI:-0.87 to -0.30)), trabecular thickness (ß:-0.55 (95% CI:-0.87 to -0.23)), cortical thickness (ß:-0.41 (95% CI:-0.74 to -0.08)), log cortical pore volume (ß:-0.43 (95% CI:-0.73 to -0.13)), bone stiffness (ß:-0.39 (95% CI:-0.62 to -0.17)) and failure load (ß:-0.39 (95% CI:-0.60 to -0.17)) when compared to the non-insulin users. Insulin use was not associated with cortical vBMD, trabecular number, trabecular separation, cortical porosity and cortical pore diameter. This study indicates that insulin use is negatively associated with bone density, bone micro-architectural and bone strength parameters. These findings may partly explain the previously observed increased fracture risk in insulin users, although there may be residual confounding by other factors related to disease severity in insulin users.


Assuntos
Densidade Óssea/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Fraturas Ósseas/fisiopatologia , Idoso , Estudos Transversais , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Análise de Elementos Finitos , Fraturas Ósseas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
8.
Spine (Phila Pa 1976) ; 39(25): E1503-9, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25417826

RESUMO

STUDY DESIGN: In vivo analysis in an ovine model. OBJECTIVE: To evaluate the feasibility of radiopaque ultrahigh molecular weight polyethylene (UHMWPE) sublaminar wires in a growth-guidance spinal system by assessing stability, biocompatibility, and growth potential. SUMMARY OF BACKGROUND DATA: Several growth-guidance systems have been developed for the treatment of early-onset scoliosis. The use of gliding pedicle screws and metal sublaminar wires during these procedures can cause metal-on-metal debris formation and neurological deficits. Novel radiopaque UHMWPE wires are introduced to safely facilitate longitudinal growth and provide stability in a growth-guidance system for early-onset scoliosis. METHODS: Twelve immature sheep received posterior segmental spinal instrumentation; pedicle screws were inserted at L5 and radiopaque UHMWPE (bismuth trioxide) wires were passed sublaminarly at each level between L3 and T12 and fixed to dual cobalt-chromium rods. Four age-matched animals that were not operated were evaluated to serve as a control group. Radiographs were obtained to measure growth of the instrumented segment. After 24 weeks, the animals were killed and the spines were harvested for histological evaluation and high-resolution peripheral quantitative computed tomographic analysis. RESULTS: No neurological deficits occurred and all instrumentation remained stable. One animal died from an unknown cause. Substantial growth occurred in the instrumented segments (L5-T11) in the intervention group (27 ± 2 mm), which was not significantly different to the control group, (30 ± 4 mm, P = 0.42). High-resolution peripheral quantitative computed tomographic analysis clearly showed safe routing and fixation of the UHMWPE wires and instrumentation. Despite the noted growth, ectopic bone formation with the formation of bony bridges was observed in all animals. Histology revealed no evidence of chronic inflammation or wear debris. CONCLUSION: This study shows the first results of radiopaque UHMWPE sublaminar wires as part of a growth-guidance spinal system. UHMWPE sublaminar wires facilitated near-normal longitudinal spinal growth. All instrumentation remained stable throughout follow-up; no wire breakage or loosening occurred and no adverse local-tissue response to these wires was observed. LEVEL OF EVIDENCE: N/A.


Assuntos
Fios Ortopédicos , Meios de Contraste/química , Polietilenos/química , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Imageamento Tridimensional , Ovinos , Tomografia Computadorizada por Raios X
9.
Schizophr Res ; 146(1-3): 209-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23522906

RESUMO

Schizophrenia research has identified deficits in neurocognition, social cognition, and sensory processing. Because a cohesive model of "disturbed cognitive machinery" is currently lacking, we built a conceptual model to integrate neurocognition, social cognition, and sensory processing. In a cross-sectional study, the cognitive performance of participants was measured. In accordance with the Schedules for Clinical Assessment in Neuropsychiatry, the participants were assigned to either the schizophrenia group or the non-schizophrenic psychosis group. Exclusion criteria included substance abuse, serious somatic/neurological illness, and perceptual handicap. The male/female ratio, educational level, and handedness did not differ significantly between the groups. The data were analyzed using structural equation modeling. Based upon the results of all possible pairwise models correlating neurocognition, social cognition, and sensory processing, three omnibus models were analyzed. A statistical analysis of a pairwise model-fit (χ(2), CFI, and RMSEA statistics) revealed poor interrelatedness between sensory processing and neurocognition in schizophrenia patients compared with healthy control participants. The omnibus model that predicted disintegration between sensory processing and neurocognition was statistically confirmed as superior for the schizophrenia group (χ(2)(53) of 56.62, p=0.341, RMSEA=0.04, CFI=0.95). In healthy participants, the model predicting maximal interrelatedness between sensory processing/neurocognition and neurocognition/social cognition gave the best fit (χ(2)(52) of 53.74, p=0.408, RMSEA=0.03, CFI=0.97). The performance of the patients with non-schizophrenic psychosis fell between the schizophrenia patients and control participants. These findings suggest increasing separation between sensory processing and neurocognition along the continuum from mental health to schizophrenia. Our results support a conceptual model that posits disintegration between sensory processing of social stimuli and neurocognitive processing.


Assuntos
Transtornos da Percepção Auditiva/etiologia , Transtornos Cognitivos/etiologia , Modelos Psicológicos , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Comportamento Social , Estimulação Acústica , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica
10.
Schizophr Res ; 122(1-3): 136-43, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20554159

RESUMO

BACKGROUND: Deficits in emotion perception are a well-established phenomenon in schizophrenic patients and studies have typically used unimodal emotion tasks, presenting either emotional faces or emotional vocalizations. We introduced bimodal emotion conditions in two previous studies in order to study the process of multisensory integration of visible and audible emotion cues. We now build on our earlier work and address the regulatory effects of selective attention mechanisms on the ability to integrate emotion cues stemming from multisensory channels. METHODS: We added a neutral secondary distractor condition to the original bimodal paradigm in order to investigate modality-specific selective attention mechanisms. We compared schizophrenic patients (n=50) to non-schizophrenic psychotic patients (n=46), as well as to healthy controls (n=50). A trained psychiatrist used the Schedules of Clinical Assessment in Neuropsychiatry (SCAN 2.1) to diagnose the patients. RESULTS: As expected, in healthy controls, and to a lesser extent in non-schizophrenic psychotic patients, modality-specific attention attenuated multisensory integration of emotional faces and vocalizations. Conversely, in schizophrenic patients, auditory and visual distractor conditions yielded unaffected and even exaggerated multisensory integration. CONCLUSIONS: These results suggest that schizophrenics, as compared to healthy controls and non-schizophrenic psychotic patients, have modality-specific attention deficits when attempting to integrate information regarding emotions that stem from multichannel sources. Various explanations for our findings, as well as their possible consequences, are discussed.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Emoções , Transtornos da Percepção/etiologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Estimulação Acústica/métodos , Adulto , Análise de Variância , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Percepção Auditiva/fisiologia , Discriminação Psicológica , Face , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos/fisiologia , Transtornos da Percepção/diagnóstico , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia
11.
Schizophr Res ; 107(2-3): 286-93, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18986799

RESUMO

Since Kraepelin called dementia praecox what we nowadays call schizophrenia, cognitive dysfunction has been regarded as central to its psychopathological profile. Disturbed experience and integration of emotions are, both intuitively and experimentally, likely to be intermediates between basic, non-social cognitive disturbances and functional outcome in schizophrenia. While a number of studies have consistently proven that, as part of social cognition, recognition of emotional faces and voices is disturbed in schizophrenics, studies on multisensory integration of facial and vocal affect are rare. We investigated audiovisual integration of emotional faces and voices in three groups: schizophrenic patients, non-schizophrenic psychosis patients and mentally healthy controls, all diagnosed by means of the Schedules of Clinical Assessment in Neuropsychiatry (SCAN 2.1). We found diminished crossmodal influence of emotional faces on emotional voice categorization in schizophrenics, but not in non-schizophrenia psychosis patients. Results are discussed in the perspective of recent theories on multisensory integration.


Assuntos
Transtornos Cognitivos/diagnóstico , Emoções , Expressão Facial , Reconhecimento Visual de Modelos , Transtornos Psicóticos/diagnóstico , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Percepção da Fala , Adulto , Transtornos Cognitivos/psicologia , Discriminação Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/psicologia , Adulto Jovem
12.
Intervirology ; 49(3): 127-32, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16428888

RESUMO

The design of a new HBsAg screening assay, the Hepanostika HBsAg Ultra is based on the use of monoclonal antibodies raised against native wild-type HBsAg and reactive with HBsAg in which the common 'a'-determinant is modified by site-directed mutagenesis of four of the cysteine moieties. The design was checked using the same cysteine variants and samples from patients known to be infected with HBsAg variants. The results found were compared with other state-of-the-art commercial screening assays. The design of the Hepanostika HBsAg Ultra enabled detection of all variant HBsAg-positive samples in contrast to the other commercial assays. An additional 980 samples were tested to assess the specificity and sensitivity of the Hepanostika HBsAg Ultra. Screening of presumed negative serum and plasma samples resulted in a specificity of 100%. This makes the Hepanostika HBsAg Ultra the first screening assay with a design able to detect HBsAg variants with high sensitivity and specificity.


Assuntos
Ensaio de Imunoadsorção Enzimática , Antígenos de Superfície da Hepatite B/sangue , Hepatite B/diagnóstico , Animais , Anticorpos Monoclonais/imunologia , Variação Antigênica/imunologia , Doadores de Sangue , Antígenos de Superfície da Hepatite B/classificação , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Camundongos , Sensibilidade e Especificidade
13.
J Phys Chem A ; 109(42): 9437-42, 2005 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-16866392

RESUMO

The switching behavior of 1,2-bis(5-phenyl-2-methylthien-3-yl)perfluorocyclopentene and its nonfluorinated (perhydro) analogue are compared. For both molecules, the dynamics after optical excitation can be separated into three regimes: preswiching due to excited state mixing; the ring closure itself; postswitching related to vibrational cooling. The fluorinated version switches faster than its nonfluorinated analogue by about a factor of 4.7. This is explained by electronic level shifts near the crossing region between the S(1) and S(0) potential energy surfaces. In the nonfluorinated molecule the various levels involved in the switching have well-separated transition frequencies, which allow for a clear interpretation of experimental data. Thus, the fluorinated molecule makes a better (more efficient and faster) switch, but the nonfluorinated molecule provides a better model system for fundamental studies.

14.
Phys Rev Lett ; 91(20): 207402, 2003 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-14683393

RESUMO

We investigate photochromic molecular switches that are self-assembled on gold. We use two experimental techniques; namely, the mechanically controllable break-junction technique to measure electronic transport, and UV/Vis spectroscopy to measure absorption. We observe switching of the molecules from the conducting to the insulating state when illuminated with visible light (lambda=546 nm), in spite of the gold surface plasmon absorption present around this wavelength. However, we fail to observe the reverse process which should occur upon illumination with UV light (lambda=313 nm). We attribute this to quenching of the excited state of the molecule in the open form by the presence of gold.

15.
AIDS Res Hum Retroviruses ; 17(11): 1003-8, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11485617

RESUMO

Next to a profound T cell immunodeficiency, HIV-1 infection induces activation and dysfunction of B cells, resulting in hypergammaglobulinemia. Whereas T cell immune reconstitution with potent antiretroviral therapy has been extensively documented, limited data are available on B cell immune reconstitution. We studied the effect of potent antiretroviral therapy on antibody titers to the viral proteins gp120 and p24 and on total IgG concentrations. Three retrospectively chosen groups were studied: a successfully treated group, untreated controls, and subjects with virological failure after several months of successful therapy. In the successfully treated group, the median total IgG concentrations normalized, whereas they remained elevated in the untreated group and rebounded after an initial decline in the therapy failure group. The HIV-1-specific antibody titers declined in the successfully treated group and followed the rebound of the HIV RNA levels in the therapy failure group. With potent antiretroviral therapy the hypergammaglobulinemia normalized whereas HIV-1-specific immune responses were weakened. The weakening of antiviral immunity with therapy may be relevant for current attempts to gain immunological control over the virus through structured treatment interruptions or therapeutic vaccinations.


Assuntos
Fármacos Anti-HIV/farmacologia , Anticorpos Anti-HIV/efeitos dos fármacos , Proteína do Núcleo p24 do HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/tratamento farmacológico , HIV-1 , Hipergamaglobulinemia/tratamento farmacológico , Adulto , Fármacos Anti-HIV/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Quimioterapia Combinada , Feminino , Proteína do Núcleo p24 do HIV/efeitos dos fármacos , Proteína gp120 do Envelope de HIV/efeitos dos fármacos , Infecções por HIV/imunologia , Humanos , Imunoglobulina G/imunologia , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Estudos Retrospectivos , Ritonavir/uso terapêutico , Falha de Tratamento , Carga Viral , Zidovudina/uso terapêutico
16.
Int J Antimicrob Agents ; 16(4): 463-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11118859

RESUMO

Broad use of antiretroviral drugs is becoming a factor that is important to consider for understanding the HIV-1 epidemiology. Since 1993, we observe that a proportion of new infections within major risk groups in Amsterdam is caused by azidothymidine (AZT)-resistant viruses. After the introduction of combination therapy in The Netherlands in 1997, new infections with drug-resistant viruses have not been documented. Large-scale monitoring of anti-HIV-1 therapy failures revealed that antiretroviral drugs may yield previously undescribed resistant viruses, which contain a two amino acid insertion (68SS/V69) within their reverse transcriptase genes in combination with mutations at codons 67 and 215. These viruses are highly resistant to AZT, 3TC, and d4T, and moderately resistant to ddI and ddC.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/genética , Epidemiologia Molecular , Sequência de Aminoácidos , Fármacos Anti-HIV/farmacologia , Resistência Microbiana a Medicamentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Países Baixos/epidemiologia , Homologia de Sequência de Aminoácidos
17.
AIDS Res Hum Retroviruses ; 16(9): 867-70, 2000 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-10875612

RESUMO

The HIV-1 syncytium-inducing phenotype is determined by virus replication and the presence of cytopathic effects in MT-2 cells. There is a strong correlation between the syncytium-inducing/MT-2-tropic phenotype and positively charged amino acids at positions 306 and 320 in the V3 loop for HIV-1 subtypes A, B, D, and E. In contrast, a lack of correlation between signature amino acids and syncytium formation in MT-2 cells for subtype F viruses from Romania has been reported. Virus phenotype and V3 loop amino acid sequences from Romanian HIV-1 subtype F isolates were further investigated in the present study. While the determinants of MT-2 tropism are clearly harbored in the V3 loop of subtype F isolates from Romania, the induction of syncytium formation occurs in the presence or absence of positively charged amino acids at positions 306, 320, and/or 324. However, the net positive charge of V3 loop sequences derived from syncytium-inducing viruses was higher than that of the nonsyncytium-inducing isolate.


Assuntos
Proteína gp120 do Envelope de HIV/genética , HIV-1/classificação , HIV-1/patogenicidade , Fragmentos de Peptídeos/genética , Sequência de Aminoácidos , Aminoácidos/química , Linhagem Celular , Efeito Citopatogênico Viral/genética , Eletroquímica , Proteína gp120 do Envelope de HIV/química , HIV-1/genética , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fenótipo , Homologia de Sequência de Aminoácidos
18.
Ned Tijdschr Geneeskd ; 143(41): 2033-7, 1999 Oct 09.
Artigo em Holandês | MEDLINE | ID: mdl-10560542

RESUMO

In three patients, two males aged 66 and 67 years with among other disorders chronic obstructive pulmonary disease (COPD) and one woman aged 24 years with a history of intestinal surgery and current abdominal pain, the chest X-ray showed free air below the diaphragm. The two males had no major abdominal symptoms, but they did have pneumonia. All were treated conservatively. Of the males, one died from pneumonia, the other recovered. The woman presented recurrent symptoms and was subjected to extensive diagnostic examinations. This revealed a marked sigmoid perforation which was repaired, after which the symptoms did not recur. Pneumoperitoneum indicates rupture or perforation of a hollow viscus in up to 90%. In these cases, prompt surgical management is the therapy of choice. In at least 10% free air under the diaphragm is due to causes which do not require surgical treatment. These causes can be divided into intra-abdominal, intrathoracic, gynaecological and iatrogenic diseases. Conservative management should only be considered if followed by frequent and intensive evaluation of the patient's condition.


Assuntos
Colo Sigmoide/patologia , Perfuração Intestinal/complicações , Pneumopatias Obstrutivas/complicações , Pneumonia/complicações , Pneumoperitônio/etiologia , Adulto , Idoso , Colo Sigmoide/cirurgia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Perfuração Intestinal/diagnóstico , Perfuração Intestinal/cirurgia , Pneumopatias Obstrutivas/diagnóstico , Masculino , Pneumonia/diagnóstico , Pneumoperitônio/diagnóstico por imagem , Pneumoperitônio/terapia , Radiografia , Resultado do Tratamento
19.
AIDS ; 13(1): 75-80, 1999 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-10207547

RESUMO

OBJECTIVE: To identify genotypic drug resistance patterns of HIV-1 in patients who were extensively pretreated with anti-HIV drugs and not responding to their current antiretroviral combination therapy. METHODS: Drug susceptibility of the viruses was tested by a phenotypic recombinant virus assay. Genotypic analysis of HIV resistance was performed by sequencing of the amino-terminal part of the corresponding reverse transcriptase (RT) gene (amino acids 1-280) for serum-derived and recombinant viruses. RESULTS: Among viruses from 92 patients studied, three (3%) viruses contained a T215Y amino-acid change as well as a previously unseen combination of an amino-acid change at codon 67 (N-->E/S) and a two amino-acid insertion between codons 68 and 69 of the RT gene of HIV-1. Phenotypic resistance analysis showed high levels of resistance to zidovudine, lamivudine and stavudine (in all patients) and moderate levels of resistance to didanosine and zalcitabine (in two patients), whereas neither serum-derived nor recombinant viruses contained previously known amino-acid changes conferring resistance to didanosine, zalcitabine, lamivudine and stavudine. However, all recombinant viruses contained an insertion of two amino acids between codons 68 and 69 of RT as well as an amino-acid change at codon 67, as was seen in the serum-derived viruses. CONCLUSIONS: Antiretroviral therapy including zidovudine may yield replicating viruses with a two amino-acid insertion in RT in combination with amino-acid changes at codons 67 and 215, which are highly resistant to lamivudine and stavudine on top of zidovudine and have unpredictable susceptibility to didanosine and zalcitabine despite lack of previously reported corresponding resistance-associated amino-acid changes. It is currently unknown what regimens can induce the emergence of this type of multidrug-resistant viruses. This will only be elucidated when resistance assays are capable of detecting these mutants.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Didesoxinucleosídeos/uso terapêutico , Infecções por HIV/virologia , Transcriptase Reversa do HIV/genética , HIV-1/enzimologia , Nevirapina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Tirosina/genética , Adulto , Aminoácidos , Resistência Microbiana a Medicamentos , Genótipo , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênese Insercional , Fenótipo
20.
Transpl Int ; 12(1): 71-3, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10080410

RESUMO

In April 1997, a 58-year-old renal transplant recipient presented with abscess-like nodules in his left calf and on his right foot. Furuncular disease was suspected and the patient was treated with flucloxacillin. However, the lesions increased in size and became ulcerative. In the following 3 months, cultures of punctuated material, blood, and urine remained negative and gram stains did not reveal micro-organisms. In June 1997, acid-fast stains were positive. A diagnosis of a nontuberculous mycobacterium (NTM) infection was made and empirical antimycobacterial therapy was started. The combination of relatively minor symptoms with enlarged purulent lesions, causing severe morbidity, raises the possibility of NTM infection in the immunocompromised patient.


Assuntos
Quimioterapia Combinada/uso terapêutico , Transplante de Rim , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Complicações Pós-Operatórias , Dermatopatias Bacterianas/diagnóstico , Claritromicina/uso terapêutico , Etambutol/uso terapêutico , , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/isolamento & purificação , Ofloxacino/uso terapêutico , Rifampina/uso terapêutico , Dermatopatias Bacterianas/tratamento farmacológico
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