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1.
Nature ; 619(7970): 487-490, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468588

RESUMO

Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

2.
Nature ; 607(7918): 256-259, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831603

RESUMO

Fast radio bursts (FRBs) are millisecond-duration flashes of radio waves that are visible at distances of billions of light years1. The nature of their progenitors and their emission mechanism remain open astrophysical questions2. Here we report the detection of the multicomponent FRB 20191221A and the identification of a periodic separation of 216.8(1) ms between its components, with a significance of 6.5σ. The long (roughly 3 s) duration and nine or more components forming the pulse profile make this source an outlier in the FRB population. Such short periodicity provides strong evidence for a neutron-star origin of the event. Moreover, our detection favours emission arising from the neutron-star magnetosphere3,4, as opposed to emission regions located further away from the star, as predicted by some models5.

3.
Acta Psychiatr Scand ; 138(3): 267-273, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29959765

RESUMO

OBJECTIVE: We conducted a 12-week double-blind study of stabilization pharmacotherapy in patients with remitted psychotic depression (PD). METHODS: Seventy-one persons aged 18 years or older who had achieved remission of PD when randomized to either olanzapine plus sertraline or olanzapine plus placebo were continued on the double-blind treatment associated with remission. Symptoms of depression and psychosis, and weight, were measured once every 4 weeks. Cholesterol, triglycerides, and glucose were measured at stabilization phase baseline and Week 12/termination. RESULTS: The effect of treatment did not significantly change with time for depression, weight, or metabolic measures in the stabilization phase. Eight of the 71 participants (11.3%; 95% CI: 5.8, 20.7) experienced a relapse of major depression, psychosis, or both. Treatment groups did not differ in the frequency of relapse. In the entire study group, the adjusted estimate for change in weight was an increase of 1.66 kg (95% CI: 0.83, 2.48) and the adjusted estimate for change in total cholesterol was a decrease of 14.8 mg/dL (95% CI: 3.5, 26.1) during the 12-week stabilization phase; the remaining metabolic measures did not significantly change. CONCLUSION: Continuation of acute treatment was associated with stability of remission.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Olanzapina/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Sertralina/uso terapêutico , Adulto , Idoso , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , Glicemia/análise , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Transtorno Depressivo Maior/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina/administração & dosagem , Placebos/administração & dosagem , Indução de Remissão/métodos , Sertralina/administração & dosagem , Triglicerídeos/sangue
4.
Curr Oncol ; 24(2): e157-e162, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28490940

RESUMO

OBJECTIVE: The aim of the present work was to make recommendations about the use of systemically administered drugs in combination or in sequence with radiation (rt) or surgery, or both, for cure or organ preservation, or both, in patients with locally advanced nonmetastatic (stages iii-ivb) squamous cell carcinoma of the head and neck (lascchn). METHODS: The Meta-analysis of Chemotherapy in Head and Neck Cancer (mach-nc) reports have, de facto, guided practice since 2000, and so we searched the literature for systematic reviews published from January 2000 to February 2015 in reference to five research questions. A search was also conducted up to February 2015 for randomized trials (rcts) not included in the meta-analyses. Recommendations were constructed using the Cancer Care Ontario Program in Evidence-Based Care practice guidelines development cycle. RESULTS: In addition to updated mach-nc reports, five additional meta-analyses and thirty rcts were identified. Five recommendations for lascchn treatment were generated based on those data. Concurrent chemoradiation (ccrt) is recommended to maximize the chance of cure in patients less than 71 years of age when rt is used as definitive treatment. The same recommendation also applies to patients with resected lascchn considered to be at high risk for locoregional recurrence. For lascchn patients who are candidates for organ preservation strategies and would otherwise require total laryngectomy, either ccrt or induction chemotherapy, followed by rt or surgery based on tumour response is recommended. The addition of cetuximab to intensified rt (concomitant boost or hyperfractionated schedule) is an alternative to ccrt. Routine use of induction chemotherapy to improve overall survival is not recommended. CONCLUSIONS: We were able to use high-level evidence from patients receiving rt as definitive or postoperative treatment to generate recommendations for the use of systemic therapy in the treatment of lascchn. A limitation is a lack of stratification for human papillomavirus-related cancers of the oropharynx. One rct provided evidence for the use of cetuximab as an alternative to chemotherapy in the definitive rt setting. Concurrent chemoradiation provides one strategy for larynx preservation, but the best strategy is unclear. Use of induction chemotherapy does not improve overall survival, and its use should be limited to patients requiring immediate tumour downsizing before local therapy.

5.
Curr Oncol ; 23(6): 418-424, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28050138

RESUMO

BACKGROUND: Updated practice guidelines on adjuvant chemotherapy for completely resected colon cancer are lacking. In 2008, Cancer Care Ontario's Program in Evidence-Based Care developed a guideline on adjuvant therapy for stages ii and iii colon cancer. With newer regimens being assessed in this patient population and older agents being either abandoned because of non-effectiveness or replaced by agents that are more efficacious, a full update of the original guideline was undertaken. METHODS: Literature searches (January 1987 to August 2015) of medline, embase, and the Cochrane Library were conducted; in addition, abstracts from the American Society of Clinical Oncology, the European Society for Medical Oncology, and the European Cancer Congress were reviewed (the latter for January 2007 to August 2015). A practice guideline was drafted that was then scrutinized by internal and external reviewers whose comments were incorporated into the final guideline. RESULTS: Twenty-six unique reports of eighteen randomized controlled trials and thirteen unique reports of twelve meta-analyses or pooled analyses were included in the evidence base. The 5 recommendations developed included 3 for stage ii colon cancer and 2 for stage iii colon cancer. CONCLUSIONS: Patients with completely resected stage iii colon cancer should be offered adjuvant 5-fluorouracil (5fu)-based chemotherapy with or without oxaliplatin (based on definitive data for improvements in survival and disease-free survival). Patients with resected stage ii colon cancer without "high-risk" features should not receive adjuvant chemotherapy. For patients with "high-risk" features, 5fu-based chemotherapy with or without oxaliplatin should be offered, although no clinical trials have been conducted to conclusively demonstrate the same benefits seen in stage iii colon cancer.

6.
Acta Psychiatr Scand ; 132(5): 335-44, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26016647

RESUMO

OBJECTIVE: Unipolar psychotic depression (PD) is a severe and debilitating syndrome, which requires intensive monitoring. The objective of this study was to provide an overview of the rating scales used to assess illness severity in PD. METHOD: Selective review of publications reporting results on non-self-rated, symptom-based rating scales utilized to measure symptom severity in PD. The clinical and psychometric validity of the identified rating scales was reviewed. RESULTS: A total of 14 rating scales meeting the predefined criteria were included in the review. These scales grouped into the following categories: (i) rating scales predominantly covering depressive symptoms, (ii) rating scales predominantly covering psychotic symptoms, (iii) rating scales covering delusions, and (iv) rating scales covering PD. For the vast majority of the scales, the clinical and psychometric validity had not been tested empirically. The only exception from this general tendency was the 11-item Psychotic Depression Assessment Scale (PDAS), which was developed specifically to assess the severity of PD. CONCLUSION: In PD, the PDAS represents the only empirically derived rating scale for the measurement of overall severity of illness. The PDAS should be considered in future studies of PD and in clinical practice.


Assuntos
Transtornos Bipolares e Relacionados/diagnóstico , Transtorno Depressivo/diagnóstico , Escalas de Graduação Psiquiátrica , Psicometria/instrumentação , Transtornos Psicóticos/diagnóstico , Índice de Gravidade de Doença , Humanos
7.
Ann Oncol ; 25(5): 1039-44, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24562448

RESUMO

BACKGROUND: Preoperative chemoradiotherapy (CRT) improves outcomes in patients with locally advanced but resectable adenocarcinoma of the esophagus. ACOSOG Z4051 evaluated CRT with docetaxel, cisplatin, and panitumumab (DCP) in this patient group with a primary end point of a pathologic complete response (pCR) ≥35%. PATIENTS AND METHODS: From 15 January 2009 to 22 July 2011, 70 patients with locally advanced but resectable distal esophageal adenocarcinoma were enrolled. Patients received docetaxel (40 mg/m(2)), cisplatin (40 mg/m(2)), and panitumumab (6 mg/kg) on weeks 1, 3, 5, 7, and 9 with RT (5040 cGy, 180 cGy/day × 28 days) beginning week 5. Resection was planned after completing CRT. PCR was defined as no viable residual tumor cells. Secondary objectives included near-pCR (≤10% viable cancer cells), toxicity, and overall and disease-free survival. Adverse events were graded using the CTCAE Version 3.0. RESULTS: Five of 70 patients were ineligible. Of 65 eligible patients (59 M; median age 61), 11 did not undergo surgery, leaving 54 assessable. PCR rate was 33.3% and near-pCR was 20.4%. Secenty-three percent of patients completed DCP (n = 70) and 92% completed RT. 48.5% had toxicity ≥grade 4. Lymphopenia (43%) was most common. Operative mortality was 3.7%. Adult respiratory distress syndrome was encountered in two patients (3.7%). At median follow-up of 26.3 months, median overall survival was 19.4 months and 3-year overall survival was 38.6% (95% confidence interval 24.5% to 60.8%). CONCLUSIONS: Neoadjuvant CRT with DCP is active (pCR + near-pCR = 53.7%) but toxicity is significant. Further evaluation of this regimen in an unselected population is not recommended. CLINICALTRIALSGOV IDENTIFIER: NCT00757172.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/terapia , Junção Esofagogástrica/patologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Quimiorradioterapia Adjuvante , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Docetaxel , Neoplasias Esofágicas/mortalidade , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Panitumumabe , Taxoides/administração & dosagem , Resultado do Tratamento
9.
Acta Psychiatr Scand ; 129(3): 211-20, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23799875

RESUMO

OBJECTIVE: Psychotic depression (PD) is a highly debilitating condition, which needs intensive monitoring. However, there is no established rating scale for evaluating the severity of PD. The aim of this analysis was to assess the psychometric properties of established depression rating scales and a number of new composite rating scales, covering both depressive and psychotic symptoms, in relation to PD. METHOD: The psychometric properties of the rating scales were evaluated based on data from the Study of Pharmacotherapy of Psychotic Depression. RESULTS: A rating scale consisting of the 6-item Hamilton melancholia subscale (HAM-D6 ) plus five items from the Brief Psychiatric Rating Scale (BPRS), named the HAMD-BPRS11 , displayed clinical validity (Spearman's correlation coefficient between HAMD-BPRS11 and Clinical Global Impression - Severity (CGI-S) scores = 0.79-0.84), responsiveness (Spearman's correlation coefficient between change in HAMD-BPRS11 and Clinical Global Impression - Improvement (CGI-I) scores = -0.74--0.78) and unidimensionality (Loevinger's coefficient of homogeneity = 0.41) in the evaluation of PD. The HAM-D6 fulfilled the same criteria, whereas the full 17-item Hamilton Depression Scale failed to meet criteria for unidimensionality. CONCLUSION: Our results suggest that the HAMD-BPRS11 is a more valid measure than pure depression scales for evaluating the severity of PD.


Assuntos
Transtornos Psicóticos Afetivos/diagnóstico , Escalas de Graduação Psiquiátrica/normas , Adulto , Transtornos Psicóticos Afetivos/fisiopatologia , Escalas de Graduação Psiquiátrica Breve , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Psicometria/instrumentação , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
10.
Clin Exp Immunol ; 167(1): 158-68, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22132895

RESUMO

Immune responses to human leucocyte antigen (HLA) and self-antigen collagen V (Col-V) have been proposed in the pathogenesis of chronic rejection (bronchiolitis obliterans syndrome, BOS) following human lung transplantation (LTx). In this study, we defined the role for the shift in immunodominant epitopes of Col-V in inducing T helper phenotype switch leading to immunity to Col-V and BOS. Sera and lavage from BOS(+) LTx recipients with antibodies to Col-V were analysed. Two years prior to BOS, patients developed antibodies to both Col-V,α1(V) and α2(V) chains. However, at clinical diagnosis of BOS, antibodies became restricted to α1(V). Further, lung biopsy from BOS(+) patients bound to antibodies to α1(V), indicating that these epitopes are exposed. Fourteen Col-V peptides [pep1-14, pep1-4 specific to α1(V), pep5-8 to α1,2(V) and pep9-14 to α2(V)] which bind to HLA-DR4 and -DR7, demonstrated that prior to BOS, pep 6, 7, 9, 11 and 14 were immunodominant and induced interleukin (IL)-10. However, at BOS, the response switched to pep1, 4 and 5 and induced interferon (IFN)-γ and IL-17 responses, but not IL-10. The T helper (Th) phenotype switch is accompanied by decreased frequency of regulatory T cells (T(regs) ) in the lavage. LTx recipients with antibodies to α1(V) also demonstrated increased matrix metalloproteinase (MMP) activation with decreased MMP inhibitor, tissue inhibitor of metalloproteinase (TIMP), suggesting that MMP activation may play a role in the exposure of new Col-V antigenic epitopes. We conclude that a shift in immunodominance of self-antigenic determinants of Col-V results in induction of IFN-γ and IL-17 with loss of tolerance leading to autoimmunity to Col-V, which leads to chronic lung allograft rejection.


Assuntos
Autoantígenos/imunologia , Bronquiolite Obliterante/imunologia , Colágeno Tipo I/imunologia , Colágeno Tipo V/imunologia , Rejeição de Enxerto/imunologia , Epitopos Imunodominantes/imunologia , Transplante de Pulmão/imunologia , Tolerância a Antígenos Próprios/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Sequência de Aminoácidos , Bronquiolite Obliterante/etiologia , Metilação de DNA , Ativação Enzimática , Feminino , Seguimentos , Fatores de Transcrição Forkhead/genética , Humanos , Imunofenotipagem , Imunossupressores/uso terapêutico , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-17/biossíntese , Interleucina-17/genética , Isoantígenos/imunologia , Pulmão/imunologia , Pulmão/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Tolerância ao Transplante/imunologia
11.
Nat Med ; 4(10): 1193-6, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9771756

RESUMO

The development of prophylactic vaccines against retroviral diseases has been impeded by the lack of obvious immune correlates for protection. Cytotoxic T-lymphocyte (CTL), CD4-lymphocyteS, chemokine and/or antibody responses have all been associated with protection against HIV and AIDS; however, effective and safe vaccination strategies remain elusive. Here we show that vaccination with a minimal ovine CTL peptide epitope identified within gp51 of the retrovirus bovine leukemia virus (BLV), consistently induced peptide-specific CTLs. Only sheep whose CTLs were also capable of recognizing retrovirus-infected cells were fully protected when challenged with BLV. This retrovirus displays limited sequence variation; thus, in the relative absence of confounding CTL escape variants, virus-specific CTLs targeting a single epitope were able to prevent the establishment of a latent retroviral infection.


Assuntos
Infecções por Deltaretrovirus/veterinária , Vírus da Leucemia Bovina/imunologia , Leucemia Linfocítica Crônica de Células B/veterinária , Doenças dos Ovinos/imunologia , Linfócitos T Citotóxicos/imunologia , Vacinas Virais/imunologia , Animais , Infecções por Deltaretrovirus/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Ovinos , Proteínas do Envelope Viral/imunologia , Latência Viral
12.
Curr Oncol ; 27(2): e106-e114, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32489260

RESUMO

Background: Practice guidelines based on a systematic review of the literature regarding the nonsurgical management of hepatocellular carcinoma (hcc) in North America are lacking. Resection and transplantation are the foundations for cure of hcc; however, most patients are diagnosed at an advanced stage, precluding those curative treatments. A number of local or regional therapies are used and are followed by systemic therapy for advanced or progressive disease. Other treatments are available, but their efficacy, compared with those standards, is not well known. Methods: First, systematic review questions were developed. Literature searches of the medline, embase, and Cochrane library databases (January 2000 to July 2018 or January 2005 to July 2018 depending on the question) were conducted; in addition, abstracts from the 2018 annual meeting of the American Society of Clinical Oncology were reviewed. A practice guideline was drafted that was then scrutinized by internal and external reviewers. Results: Seventy-seven studies were included in the guideline: no guidelines, two systematic reviews, and seventy-five primary studies published in full (including one pooled analysis). Five recommendations were developed. Conclusions: There is no evidence for or against the use of local or regional interventions other than transarterial chemoembolization for the treatment of intermediate- or advanced-stage hcc. Furthermore, there is no evidence to support the addition of sorafenib to any local or regional therapy. Sorafenib or lenvatinib are recommended for first-line systemic treatment of intermediate-stage hcc. Regorafenib or cabozantinib provide survival benefits when given as second-line treatment. Antiviral treatment is recommended in individuals with advanced hcc who are positive for the hepatitis B surface antigen.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Humanos
13.
Neuroscience ; 159(1): 271-82, 2009 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19138725

RESUMO

The prefrontal cortices mediate cognitive functions that critically depend on local dopamine levels. In male rats, many prefrontal tasks where performance is disrupted by changes in dopamine signaling are also impaired by gonadectomy, a manipulation that increases cortical dopamine concentration, prefrontal dopamine axon density and possibly extracellular prefrontal dopamine levels as well. Because these actions could be responsible for the impairing effects of gonadectomy on prefrontal function, the question of how they might arise comes to the fore. Accordingly, the present studies asked whether dopamine levels might be increased via a hormone sensitivity of transporter-mediated dopamine uptake. Specifically, (3)H WIN 35,428 and (3)H nisoxetine, ligands selective for the dopamine (DAT)- and norepinephrine transporter (NET) respectively, were used in in vitro binding assays to ask whether gonadectomy altered transporter affinity (Kd) and/or binding site number (Bmax) in prefrontal cortex, sensorimotor cortex and/or caudate. Assays performed on tissues dissected from sham-operated, gonadectomized and gonadectomized rats supplemented with testosterone propionate or estradiol for 4 or 28 days revealed no significant group differences or obvious trends in Kd or Bmax for DAT binding or in measures of Bmax for NET binding. However, affinity constants for (3)H nisoxetine were found to be significantly higher in sensorimotor and/or prefrontal cortex of rats gonadectomized and gonadectomized and supplemented with estradiol for 4 or 28 days but similar to control in gonadectomized rats given testosterone. Because the NET contributes substantially to extracellular prefrontal dopamine clearance, these androgen-mediated effects could influence prefrontal dopamine levels and might thus be relevant for observed effects of gonadectomy on dopamine-dependent prefrontal behaviors. A hormone sensitivity of the NET could also have bearing on the prefrontal dopamine dysfunction seen in disorders like schizophrenia that disproportionately affect males, whose severity correlates with abnormal testosterone levels, and for which the NET is among suspected sites of pathology.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Cocaína/análogos & derivados , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Inibidores da Captação de Dopamina/metabolismo , Fluoxetina/análogos & derivados , Hormônios Gonadais/farmacologia , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Animais , Córtex Cerebral/metabolismo , Cocaína/metabolismo , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Fluoxetina/metabolismo , Masculino , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/antagonistas & inibidores , Orquiectomia , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Propionato de Testosterona/farmacologia , Fatores de Tempo , Trítio/metabolismo
14.
Science ; 160(3835): 1449-50, 1968 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-17817355

RESUMO

Electrophoresis measurements and electron-microscope observations with two model colloids and a polymeric flocculant show zeta-potential changes and details of floc structure. Fibers of the flocculant extend radially from the particle surface and vary in thickness from 20 to 300 angstroms. Both charge neutralization and bridging may function simultaneously.

15.
Am J Transplant ; 8(11): 2454-62, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18785961

RESUMO

Primary graft dysfunction (PGD) is a common early complication after lung transplantation. We conducted a retrospective cohort study of 334 recipients to evaluate the impact of PGD graded at 24, 48 and 72 h on the risk of bronchiolitis obliterans syndrome (BOS) development (stage 1) and progression (stages 2 and 3). We constructed multivariable Cox proportional hazards models to determine the risk of BOS attributable to PGD in the context of other potential risk factors including acute rejection, lymphocytic bronchitis and respiratory viral infections. All grades of PGD at all time points were significant risk factors for BOS development and progression independent of acute rejection, lymphocytic bronchitis and respiratory viral infections. Specifically, PGD grade 1 at T24 was associated with a relative risk of BOS stage 1 of 1.93, grade 2 with a relative risk of 2.29 and grade 3 with a relative risk of 3.31. Furthermore, this direct relationship between the severity of PGD and the risk of BOS persisted at all time points. We conclude that all grades of PGD at all time points are independent risk factors for BOS development and progression. Future strategies that might attenuate the severity of PGD may mitigate the risk of BOS.


Assuntos
Bronquiolite Obliterante/terapia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/métodos , Disfunção Primária do Enxerto/terapia , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Dis Esophagus ; 21(6): 480-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18840132

RESUMO

SUMMARY: Accurate staging of esophageal cancer is critical to achieving optimal treatment outcomes. End-oscopic ultrasound with fine needle aspiration (EUS-FNA) has emerged as a valuable tool for locoregional staging. However, it is unclear how different physician specialties perceive the benefit of EUS-FNA for esophageal cancer staging, and thus utilize this modality in clinical practice. A survey regarding utilization of EUS-FNA in esophageal cancer was distributed to 211 thoracic surgeons and 251 EUS-capable gastroenterologists. Seventy-six thoracic surgeons (36%) and 78 gastroenterologists (31%) responded to the survey. Most surgeons (75%) use EUS to stage potentially resectable esophageal cancer 75% of the time. Surgeons using EUS less often are less likely to have access to high-quality EUS services than their peers. Fewer surgeons believe EUS is the most accurate test for T and N-staging (84% and 71%, respectively) as compared with gastroenterologists (97% and 96%, P < 0.01 for both). Most endosonographers (68%) decide whether to dilate a malignant esophageal stricture to complete the staging exam on a case-by-case basis. Surgeons disagree as to whether involvement of celiac lymph nodes should preclude esophagectomy in distal esophageal cancer. While most thoracic surgeons have embraced EUS-FNA as the most accurate locoregional staging modality in esophageal cancer, this attitude is not fully reflected in utilization patterns due to a lack of quality EUS services in some centers. Controversial areas that warrant further study include dilation of malignant strictures to facilitate EUS staging, and the implication of involved celiac lymph nodes on management.


Assuntos
Biópsia por Agulha Fina/métodos , Endossonografia/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Adulto , Diagnóstico Precoce , Feminino , Gastroenterologia/normas , Gastroenterologia/tendências , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Padrões de Prática Médica , Sensibilidade e Especificidade , Inquéritos e Questionários , Cirurgia Torácica/normas , Cirurgia Torácica/tendências , Estados Unidos
17.
Clin Oncol (R Coll Radiol) ; 29(7): 459-465, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28341242

RESUMO

The objective of this systematic review was to provide current evidence regarding the use of adjuvant systemic chemotherapy for stage II and III colon cancer following curative intent surgery. MEDLINE and EMBASE databases and proceedings of American Society for Clinical Oncology and European Society of Medical Oncology/European Cancer Congress were searched through to August 2015. Systematic reviews (with or without meta-analyses) and randomised controlled trials were included. Patients with completely resected stage III colon cancer have an overall survival benefit from adjuvant chemotherapy. Combination chemotherapy (5-fluorouracil/leucovorin/oxaliplatin or capecitabine/oxaliplatin) provides a larger benefit than monotherapy but with additional toxicity. For stage II colon cancer, a clear overall survival benefit has not been shown. However, based on the subgroup analysis available, patients with high-risk stage II disease may benefit from adjuvant chemotherapy. Patients younger than 70 years of age may derive greater disease-free survival and overall survival benefit from adjuvant chemotherapy (in combination with oxaliplatin) compared with those older than 70 years. Stage II patients with microsatellite instability may have an overall survival detriment if given adjuvant chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante/métodos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/cirurgia , Idoso , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Estadiamento de Neoplasias , Ontário
18.
J Scleroderma Relat Disord ; 2(2): 115-120, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-30569018

RESUMO

PURPOSE: There is a lack of a valid, definition for skin ulcers in SSc to be used in clinical trials. Our aim was to develop a consensus definition for SSc-skin ulcers based on the results of a systematic literature review (SLR) for skin ulcer definitions and expert opinion; and to evaluate its face validity, reliability and feasibility. METHODS: SLR for skin ulcer definitions was conducted using PubMed, Web of Science, and Cochrane library for articles published from inception to January 1st, 2016. SSc experts were to discuss the definitions' categories and vote for the relevant terms. Reliability of the definition were tested in a second expert meeting, seven SSc experts evaluated 7 SSc pts with skin lesions twice. Face validity and feasibility evaluated by sending out case report forms(CRFs) to 4 SSc experts, they were asked to use the definition in 5 pts each. RESULTS: A total of 3464 abstracts and titles were screened, and 446 articles were fully evaluated. Of these, 66 met eligibility criteria and skin ulcer definitions were extracted. SSc experts discussed, refined and voted on the consensus definition using nominal process. Kappa for inter-, intra-rater rater agreement was 0.51, 0.90 respectively. The mean time to decide if the lesion is an ulcer was 7.4 sec. All investigators endorsed the face validity of the new definition in the CRFs. CONCLUSION: Using a SLR and a nominal technique, we developed a preliminary consensus-based definition of SSc-skin ulcers. Face validity, feasibility and reliability were demonstrated for the developed definition.

19.
J Appl Physiol (1985) ; 99(3): 1056-63, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15879163

RESUMO

Caffeine increases time to fatigue [limit of endurance (T(lim))] during submaximal isometric contractions without altering whole muscle activation or neuromuscular junction transmission. We used 10 male volunteers in a randomized, double-blind, repeated-measures experiment to examine single motor unit firing rates during intermittent submaximal contractions and to determine whether administering caffeine increased T(lim) by maintaining higher firing rates. On 2 separate days, subjects performed intermittent 50% maximal voluntary contractions of the quadriceps to T(lim), 1 h after ingesting a caffeine (6 mg/kg) or placebo capsule. Average motor unit firing rates recorded with tungsten microelectrodes were constant for the duration of contractions. Caffeine increased average T(lim) by 20.5 +/- 8.1% (P < 0.05) compared with placebo conditions. This increase was due to seven subjects, termed responders, who increased T(lim) significantly. Two other subjects showed no response, and a third had a shorter T(lim). Neither the increased T(lim) nor the responders' performance could be explained by alterations in firing rates or other neuromuscular variables. However, the amplitude of the evoked twitch and its maximal instantaneous rate of relaxation did not decline to the same degree in the caffeine trial of the responders; this resulted in values 20 and 30% higher at the time point matching the end of the placebo trial (P < 0.05). The amplitude of the evoked twitch and the maximal instantaneous rate of relaxation were linearly correlated (caffeine r = 0.72, placebo r = 0.80, both P < 0.001), suggesting that the increase in T(lim) may be partially explained by caffeine's effects on calcium reuptake and twitch force.


Assuntos
Potenciais de Ação/fisiologia , Cafeína/farmacologia , Contração Isométrica/efeitos dos fármacos , Contração Isométrica/fisiologia , Neurônios Motores/fisiologia , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Esforço Físico/fisiologia , Potenciais de Ação/efeitos dos fármacos , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/fisiologia , Adulto , Método Duplo-Cego , Humanos , Masculino , Neurônios Motores/efeitos dos fármacos , Estresse Mecânico , Fatores de Tempo
20.
Arch Gen Psychiatry ; 53(4): 305-12, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8634008

RESUMO

BACKGROUND: Clinical characteristics of depression, age at illness onset, medical burden, disability, cognitive impairment, lack of social support, and poor living conditions may influence the course of depression. This study investigates the timetable of recovery and the role of the above factors in predicting recovery in elderly patients with major depression. METHODS: Recovery was studied in 63 elderly (age >63 years) and 23 younger patients with depression who were followed up for an average of 18.2 months (SD, 13.1 months) under naturalistic treatment conditions. Diagnosis was assigned according to Research Diagnostic Criteria after administration of the Schedule for Affective Disorders and Schizophrenia. The Longitudinal Follow-up Interval Examination was used to identify recovery. RESULTS: The recovery rate of depressed elderly patients was similar to that of younger depressed patients. In the elderly patients, age, antidepressant treatment, age at onset, and chronicity of episode were significantly associated with time to recovery since entry. Among these parameters, late age at onset was the strongest predictor of slow recovery. In younger patients, long time to recovery was predicted by weak social support, younger age, cognitive impairment, and low intensity of antidepressant treatment. In the elderly, the intensity of antidepressant treatment began to decline within 16 weeks from entry and approximately 10 weeks prior to recovery. CONCLUSIONS: These findings challenge the view that geriatric depression has a worse outcome than depression in younger adults. However, depressed patients with onset of first episode in late life may be at higher risk for chronicity. Antidepressant treatment prescribed by clinicians may decline prior to recovery despite evidence that high treatment intensity is effective in preventing relapse.


Assuntos
Transtorno Depressivo/diagnóstico , Adulto , Fatores Etários , Idade de Início , Idoso , Antidepressivos/uso terapêutico , Doença Crônica , Terapia Combinada , Transtorno Depressivo/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Apoio Social , Resultado do Tratamento
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