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1.
Ann Hematol ; 102(1): 99-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36409328

RESUMO

The prognostic impact of monocytosis has not yet been determined in patients with myelodysplastic syndromes (MDS). We examined absolute monocyte counts in the peripheral blood at the time of diagnosis in 1949 patients with a bone marrow blast count < 5%, a condition we call MDS < EB1 (MDS with a blast percentage lower than that of MDS with excess blasts 1, according to the WHO classification). Monocytosis (> 600/µl) was associated with higher median hemoglobin, WBC, and ANC, and more favorable karyotype (p = .001). Nevertheless, monocytosis was associated with shorter overall survival (OS) (108 vs. 126 months, p = .002) and earlier transformation into AML (p < .001). In patients with sideroblastic phenotype, the percentage of ring sideroblasts significantly correlated with the monocyte count (p = .005), and OS was significantly shorter when monocytosis was documented (88 vs. 132 months, p = .004). The survival disadvantage of patients with MDS < EB1 and peripheral blood monocytosis suggests that these patients suffer from a CMML-like disease. Even though they are generally classified as MDS with persistent monocytosis, such patients should be considered candidates for therapeutic options employed in CMML.


Assuntos
Medula Óssea , Síndromes Mielodisplásicas , Humanos , Prognóstico , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Leucocitose , Contagem de Leucócitos
2.
Eur J Nucl Med Mol Imaging ; 49(5): 1535-1543, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34850248

RESUMO

BACKGROUND: One of the challenges in the management of patients with follicular lymphoma (FL) is the identification of individuals with histological transformation, most commonly into diffuse large B-cell lymphoma (DLBCL). [18F]FDG-PET/CT is used for staging of patients with lymphoma, but visual interpretation cannot reliably discern FL from DLBCL. This study evaluated whether radiomic features extracted from clinical baseline [18F]FDG PET/CT and analyzed by machine learning algorithms may help discriminate FL from DLBCL. MATERIALS AND METHODS: Patients were selected based on confirmed histopathological diagnosis of primary FL (n=44) or DLBCL (n=76) and available [18F]FDG PET/CT with EARL reconstruction parameters within 6 months of diagnosis. Radiomic features were extracted from the volume of interest on co-registered [18F]FDG PET and CT images. Analysis of selected radiomic features was performed with machine learning classifiers based on logistic regression and tree-based ensemble classifiers (AdaBoosting, Gradient Boosting, and XG Boosting). The performance of radiomic features was compared with a SUVmax-based logistic regression model. RESULTS: From the segmented lesions, 121 FL and 227 DLBCL lesions were included for radiomic feature extraction. In total, 79 radiomic features were extracted from the SUVmap, 51 from CT, and 6 shape features. Machine learning classifier Gradient Boosting achieved the best discrimination performance using 136 radiomic features (AUC of 0.86 and accuracy of 80%). SUVmax-based logistic regression model achieved an AUC of 0.79 and an accuracy of 70%. Gradient Boosting classifier had a significantly greater AUC and accuracy compared to the SUVmax-based logistic regression (p≤0.01). CONCLUSION: Machine learning analysis of radiomic features may be of diagnostic value for discriminating FL from DLBCL tumor lesions, beyond that of the SUVmax alone.


Assuntos
Linfoma Folicular , Linfoma Difuso de Grandes Células B , Fluordesoxiglucose F18 , Humanos , Linfoma Folicular/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/patologia , Aprendizado de Máquina , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos
3.
Ann Hematol ; 101(3): 607-616, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34982196

RESUMO

Primary central nervous system non-Hodgkin lymphomas (PCNS-NHLs) are extranodal B-cell lymphomas with poor prognosis. The role of high-dose therapy (HDT) followed by autologous blood stem cell transplantation (ASCT) as first-line therapy is still not clear. We retrospectively collected long-term follow up data of 61 consecutive patients with PCNS-NHL at the University Hospital Düsseldorf from January 2004 to December 2016. Thirty-six patients were treated with conventional chemoimmunotherapy (cCIT) only (CT-group). Seventeen patients received an induction cCIT followed by HDT and ASCT. In the CT-group, the overall response rate (ORR) was 61% (CR 47%, PR 14%), and there were 8% treatment-related deaths (TRD). Progression-free survival (PFS) was 31.8 months, and overall survival (OS) was 57.3 months. In the HDT-group, the ORR was 88% (59% CR, 29% PR), and there were 6% TRD. Median PFS and OS were not reached at 5 years. The 5-year PFS and OS were 64.7%. After a median follow up of 71 months, 10 patients (59%) were still alive in CR/PR following HDT and ASCT, one patient was treated for progressive disease (PD), and 7 had died (41%, 6 PD, 1 TRD). All patients achieving CR prior to HDT achieved durable CR. In the CT-group, 8 patients (22%) were alive in CR/PR after a median follow-up of 100 months. Twenty-eight patients died (78%, 24 PD, 2 TRD, 2 deaths in remission). In the univariate analysis, the HDT-group patients had significantly better PFS (not reached vs 31.8 months, p = 0.004) and OS (not reached vs 57.3 months, p = 0.021). The multivariate analysis showed HDT was not predictive for survival. Treatment with HDT + ASCT is feasible and offers the chance for long-term survival with low treatment-related mortality in younger patients. In this analysis, ORR, PFS and OS were better with HDT than with conventional cCIT alone. This result was not confirmed in the multivariate analysis, and further studies need to be done to examine the role of HDT in PCNSL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/terapia , Transplante de Células-Tronco Hematopoéticas , Linfoma não Hodgkin/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Retrospectivos , Transplante Autólogo
4.
Ann Hematol ; 101(5): 1031-1038, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35262868

RESUMO

Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) can be late complications following mutagenic treatment. Limited data is available on the outcome of patients developing therapy-related MDS and AML after treatment for multiple myeloma (MM). We identified 250 patients with therapy-associated MDS or AML in the Duesseldorf MDS registry. Of those, 50 patients were previously diagnosed with multiple myeloma (mm-MDS/AML). We compared them to patients with de novo MDS (n = 4862) and to patients with MDS following other underlying diseases (tMDS) (n = 200). mm-MDS patients and tMDS patients showed similar karyotypes and degrees of cytopenia. However, mm-MDS patients had significantly higher blast counts and more often belonged to the high-risk group according to the International Prognostic Scoring System (IPSS) (both p < 0.05). Although the rate of progression to AML was similar in mm-MDS and tMDS, both transformed significantly more often than de novo MDS (p < 0.05). Median overall survival of patients with mm-MDS (13 months; range: 1-99) and tMDS (13 months; range 0-160) was also similar yet significantly shorter than patients with de novo MDS (32 months; range 0-345 months; p < 0.05). Furthermore, survival of mm-MDS patients was not affected by myeloma activity. Despite significantly more high-risk disease and higher blast cell counts, myeloma-associated MDS-patients show features akin to other tMDS. Survival is similar to other tMDS and irrespective of myeloma remission status or transformation to AML. Thus, patient outcome is not determined by competing clones but rather by MDS governing the stem cell niche.


Assuntos
Leucemia Mieloide Aguda , Mieloma Múltiplo , Síndromes Mielodisplásicas , Segunda Neoplasia Primária , Humanos , Cariotipagem , Leucemia Mieloide Aguda/induzido quimicamente , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Mieloma Múltiplo/complicações , Mieloma Múltiplo/terapia , Síndromes Mielodisplásicas/induzido quimicamente , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/terapia , Segunda Neoplasia Primária/etiologia
5.
BMC Gastroenterol ; 22(1): 82, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35216547

RESUMO

BACKGROUND: In patients with severe polycystic liver disease (PLD), there is a need for new treatments. Estrogens and possibly other female sex hormones stimulate growth in PLD. In some patients, liver volume decreases after menopause. Female sex hormones could therefore be a target for therapy. The AGAINST-PLD study will examine the efficacy of the GnRH agonist leuprorelin, which blocks the production of estrogen and other sex hormones, to reduce liver growth in PLD. METHODS: The AGAINST-PLD study is an investigator-driven, multicenter, randomized controlled trial. Institutional review board (IRB) approval was received at the University Medical Center of Groningen and will be collected in other sites before opening these sites. Thirty-six female, pre-menopausal patients, with a very large liver volume for age (upper 10% of the PLD population) and ongoing liver growth despite current treatment options will be randomized to direct start of leuprorelin or to 18 months standard of care and delayed start of leuprorelin. Leuprorelin is given as 3.75 mg subcutaneously (s.c.) monthly for the first 3 months followed by 3-monthly depots of 11.25 mg s.c. The trial duration is 36 months. MRI scans to measure liver volume will be performed at screening, 6 months, 18 months, 24 months and 36 months. In addition, blood will be drawn, DEXA-scans will be performed and questionnaires will be collected. This design enables comparison between patients on study treatment and standard of care (first 18 months) and within patients before and during treatment (whole trial). Main outcome is annualized liver growth rate compared between standard of care and study treatment. Secondary outcomes are PLD disease severity, change in liver growth within individuals and (serious) adverse events. The study is designed as a prospective open-label study with blinded endpoint assessment (PROBE). DISCUSSION: In this trial, we combined the expertise of hepatologist, nephrologists and gynecologists to study the effect of leuprorelin on liver growth in PLD. In this way, we hope to stop liver growth, reduce symptoms and reduce the need for liver transplantation in severe PLD. Trial registration Eudra CT number 2020-005949-16, registered at 15 Dec 2020. https://www.clinicaltrialsregister.eu/ctr-search/search?query=2020-005949-16 .


Assuntos
Leuprolida , Hepatopatias , Feminino , Humanos , Cistos , Leuprolida/uso terapêutico , Hepatopatias/tratamento farmacológico , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Clin Radiol ; 77(6): 428-435, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35367052

RESUMO

AIM: To synthesise the available evidence about the effects of modifications to diagnostic imaging reports that aim to optimise patient care. MATERIALS AND METHODS: Cochrane methods were used and CENTRAL, MEDLINE, EMBASE, and clinical trials registers were searched from inception to 31 March 2021. Randomised controlled trials of modifications to imaging reports aimed at optimising patient care for any condition were included. Two authors selected studies independently for inclusion, extracted data, assessed risk of bias, and judged certainty of evidence using GRADE. The primary outcome was quality of care (e.g., increased guideline-adherent care, reduced/increased imaging as appropriate). RESULTS: Five trials met eligibility criteria. One tested provision of information about appropriate osteoporosis treatment in bone density reports; two tested provision of criteria and treatment for heart failure in echocardiogram reports; one tested provision of reminders for when routine imaging is not needed in lumbar spine and knee radiography reports; and one tested inclusion of epidemiological data in lumbar spine imaging reports. All trials were susceptible to bias, and four did not blind all participants. Low certainty evidence from two trials found adding information about appropriate care may increase care quality compared to a standard report (RR 1.20 (95% CI 0.96 to 1.50), two trials, 1,548 participants, I2 = 49). This was supported by outcomes of two additional trials that also provided specific clinical guidance. CONCLUSIONS: The present review suggests that providing specific guidance on appropriate clinical intervention in imaging reports may improve patient care. Further high-quality trials are needed to confirm these findings. Prospective PROSPERO registration CRD42020153961.


Assuntos
Densidade Óssea , Qualidade da Assistência à Saúde , Diagnóstico por Imagem , Humanos , Estudos Prospectivos , Radiografia
7.
Ann Hematol ; 100(2): 455-463, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159566

RESUMO

The European Leukemia Net (ELN) guidelines for treatment of myelodysplastic syndromes (MDS) connect heterogeneous MDS subgroups with a number of therapeutic options ranging from best supportive care to allogeneic stem cell transplantation (alloSCT). However, it is currently unknown whether adherence to guideline recommendations translates into improved survival. The sizeable database of the Duesseldorf MDS Registry allowed us to address this question. We first performed a retrospective analysis including 1698 patients (cohort 1) to whom we retrospectively applied the ELN guidelines. We compared patients treated according to the guidelines with patients who deviated from it, either because they received a certain treatment though it was not recommended or because they did not receive that treatment despite being eligible. We also performed a prospective study with 381 patients (cohort 2) who were seen in our department and received guideline-based expert advice. Again, we compared the impact of subsequent guideline-adherent versus non-adherent treatment. For the majority of treatment options (best supportive care, lenalidomide, hypomethylating agents, low-dose chemotherapy, and intensive chemotherapy), we found that adherence to the ELN guidelines did not improve survival in cohort 1. The same was true when patient management was prospectively enhanced through guideline-based treatment advice given by MDS experts (cohort 2). The only exceptions were alloSCT and iron chelation (ICT). Patients receiving ICT and alloSCT as recommended fared significantly better than those who were eligible but received other treatment. Our analysis underscores the limited survival impact of most MDS therapies and suggests to pursue alloSCT in all suitable candidates. Graphical abstract.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bases de Dados Factuais , Fidelidade a Diretrizes , Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/terapia , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Homólogo
8.
Acta Oncol ; 60(1): 35-41, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32988268

RESUMO

INTRODUCTION: A meningeal solitary fibrous tumor (SFT), also called hemangiopericytoma, is a rare mesenchymal malignancy. Due to anatomic constrains, even after macroscopic complete surgery with curative intent, the local relapse risk is still relatively high, thus increasing the risk of dedifferentiation and metastatic spread. This study aims to better define the role of postoperative radiotherapy (RT) in meningeal SFTs. PATIENTS AND METHODS: A retrospective study was performed across seven sarcoma centers. Clinical information was retrieved from all adult patients with meningeal primary localized SFT treated between 1990 and 2018 with surgery alone (S) compared to those that also received postoperative RT (S + RT). Differences in treatment characteristics between subgroups were tested using independent samples t-test for continuous variables and chi-square tests for proportions. Local control (LC) and overall survival (OS) rates were calculated as time from start of treatment until progression or death from any cause. LC and OS in groups receiving S or S + RT were compared using Kaplan-Meier survival curves. RESULTS: Among a total of 48 patients, 7 (15%) underwent S and 41 (85%) underwent S + RT. Median FU was 65 months. LC was significantly associated with treatment. LC after S at 60 months was 60% versus 90% after S + RT (p = 0.052). Furthermore, R1 resection status was significantly associated with worse LC (HR 4.08, p = 0.038). OS was predominantly associated with the mitotic count (HR 3.10, p = 0.011). CONCLUSION: This retrospective study, investigating postoperative RT in primary localized meningeal SFT patients, suggests that combining RT to surgery in the management of this patient population may reduce the risk for local failures.


Assuntos
Hemangiopericitoma , Neoplasias Meníngeas , Tumores Fibrosos Solitários , Adulto , Hemangiopericitoma/radioterapia , Hemangiopericitoma/cirurgia , Humanos , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirurgia , Recidiva Local de Neoplasia , Estudos Retrospectivos , Tumores Fibrosos Solitários/radioterapia , Tumores Fibrosos Solitários/cirurgia
9.
Ann Oncol ; 31(11): 1506-1517, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32891793

RESUMO

Sarcomas are a heterogeneous group of malignancies with mesenchymal lineage differentiation. The discovery of neurotrophic tyrosine receptor kinase (NTRK) gene fusions as tissue-agnostic oncogenic drivers has led to new personalized therapies for a subset of patients with sarcoma in the form of tropomyosin receptor kinase (TRK) inhibitors. NTRK gene rearrangements and fusion transcripts can be detected with different molecular pathology techniques, while TRK protein expression can be demonstrated with immunohistochemistry. The rarity and diagnostic complexity of NTRK gene fusions raise a number of questions and challenges for clinicians. To address these challenges, the World Sarcoma Network convened two meetings of expert adult oncologists and pathologists and subsequently developed this article to provide practical guidance on the management of patients with sarcoma harboring NTRK gene fusions. We propose a diagnostic strategy that considers disease stage and histologic and molecular subtypes to facilitate routine testing for TRK expression and subsequent testing for NTRK gene fusions.


Assuntos
Sarcoma , Tropomiosina , Adulto , Fusão Gênica , Humanos , Proteínas de Fusão Oncogênica/genética , Inibidores de Proteínas Quinases , Receptor trkA/genética , Sarcoma/diagnóstico , Sarcoma/tratamento farmacológico , Sarcoma/genética
10.
Br J Surg ; 106(6): 756-764, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30830974

RESUMO

BACKGROUND: Multidisciplinary team (MDT) meetings have been adopted widely to ensure optimal treatment for patients with cancer. Agreements in tumour staging, resectability assessments and treatment allocation between different MDTs were assessed. METHODS: Of all patients referred to one hospital, 19 patients considered to have non-metastatic pancreatic cancer for evaluation were selected randomly for a multicentre study of MDT decisions in seven units across Northern Europe. Anonymized clinical information and radiological images were disseminated to the MDTs. All patients were reviewed by the MDTs for radiological T, N and M category, resectability assessment and treatment allocation. Each MDT was blinded to the decisions of other teams. Agreements were expressed as raw percentages and Krippendorff's α values, both with 95 per cent confidence intervals. RESULTS: A total of 132 evaluations in 19 patients were carried out by the seven MDTs (1 evaluation was excluded owing to technical problems). The level of agreement for T, N and M categories ranged from moderate to near perfect (46·8, 61·1 and 82·8 per cent respectively), but there was substantial variation in assessment of resectability; seven patients were considered to be resectable by one MDT but unresectable by another. The MDTs all agreed on either a curative or palliative strategy in less than half of the patients (9 of 19). Only fair agreement in treatment allocation was observed (Krippendorff's α 0·31, 95 per cent c.i. 0·16 to 0·45). There was a high level of agreement in treatment allocation where resectability assessments were concordant. CONCLUSION: Considerable disparities in MDT evaluations of patients with pancreatic cancer exist, including substantial variation in resectability assessments.


Assuntos
Tomada de Decisão Clínica/métodos , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Equipe de Assistência ao Paciente , Seleção de Pacientes , Padrões de Prática Médica/estatística & dados numéricos , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Variações Dependentes do Observador , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Prognóstico , Método Simples-Cego
11.
Ann Oncol ; 28(10): 2399-2408, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961825

RESUMO

Desmoid-type fibromatosis is a rare and locally aggressive monoclonal, fibroblastic proliferation characterized by a variable and often unpredictable clinical course. Currently, there is no established or evidence-based treatment approach available for this disease. Therefore, in 2015 the European Desmoid Working Group published a position paper giving recommendations on the treatment of this intriguing disease. Here, we present an update of this consensus approach based on professionals' AND patients' expertise following a round table meeting bringing together sarcoma experts from the European Organization for Research and Treatment of Cancer/Soft Tissue and Bone Sarcoma Group with patients and patient advocates from Sarcoma PAtients EuroNet. In this paper, we focus on new findings regarding the prognostic value of mutational analysis in desmoid-type fibromatosis patients and new systemic treatment options.


Assuntos
Fibromatose Agressiva/diagnóstico , Fibromatose Agressiva/terapia , Fibromatose Agressiva/genética , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Ann Oncol ; 28(6): 1230-1242, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28184416

RESUMO

Chordomas are rare, malignant bone tumors of the skull-base and axial skeleton. Until recently, there was no consensus among experts regarding appropriate clinical management of chordoma, resulting in inconsistent care and suboptimal outcomes for many patients. To address this shortcoming, the European Society of Medical Oncology (ESMO) and the Chordoma Foundation, the global chordoma patient advocacy group, convened a multi-disciplinary group of chordoma specialists to define by consensus evidence-based best practices for the optimal approach to chordoma. In January 2015, the first recommendations of this group were published, covering the management of primary and metastatic chordomas. Additional evidence and further discussion were needed to develop recommendations about the management of local-regional failures. Thus, ESMO and CF convened a second consensus group meeting in November 2015 to address the treatment of locally relapsed chordoma. This meeting involved over 60 specialists from Europe, the United States and Japan with expertise in treatment of patients with chordoma. The consensus achieved during that meeting is the subject of the present publication and complements the recommendations of the first position paper.


Assuntos
Cordoma/terapia , Guias de Prática Clínica como Assunto , Humanos , Recidiva Local de Neoplasia
17.
Osteoarthritis Cartilage ; 24(10): 1667-1681, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27224276

RESUMO

BACKGROUND: Temporal and dose-response relationships between allied health (AH) and recovery in the acute phase following lower limb (LL) arthroplasty are unclear. This systematic review investigates whether early commencement, additional therapy and/or weekend AH affects length of stay (LOS) and patient outcomes in the acute phase following LL arthroplasty. METHODS: Electronic databases were searched in February 2015. Studies were included if they evaluated any of the following aspects of AH for adults following LL arthroplasty in the acute phase: Early compared to later therapy commencement; Additional therapy; or a 6- or 7-day service compared to a lesser service. RESULTS: Twenty-four studies met the inclusion criteria, of which 19 investigated effects of physical therapy (PT) alone. Earlier PT reduced LOS (WMD = -1.23 days; 95% CI, -2.16 to -0.30) and resulted in higher probability of discharge directly home (relative risk = 1.45; 95% CI, 1.26-1.67). Addition of weekend PT reduced LOS (WMD = -1.04 days; 95% CI, -1.66 to -0.41) and improved function (SMD = 0.37; 95% CI, 0.02-0.73). Increasing PT from once to twice daily did not affect LOS (WMD = -0.35 days; 95% CI, -0.96-0.26) or function (SMD = 0.31; 95% CI, -0.06-0.71). DISCUSSION: Early PT commencement and a weekend service may produce favorable outcomes following LL arthroplasty when baseline LOS is 4 days or more. Redistributing PT resources to commence as early as day of surgery regardless of weekday may accelerate postoperative recovery. Current, high quality research is needed to confirm these findings.


Assuntos
Modalidades de Fisioterapia , Artroplastia do Joelho , Humanos , Tempo de Internação , Extremidade Inferior , Alta do Paciente
18.
Phys Rev Lett ; 116(17): 173602, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176521

RESUMO

We study the index of refraction of an ultracold bosonic gas in the dilute regime. Using phase-contrast imaging with light detuned from resonance by several tens of linewidths, we image a single cloud of ultracold atoms for 100 consecutive shots, which enables the study of the scattering rate as a function of temperature and density using only a single cloud. We observe that the scattering rate is increased below the critical temperature for Bose-Einstein condensation by a factor of 3 compared to the single-atom scattering rate. We show that current atom-light interaction models to second order of the density show a similar increase, where the magnitude of the effect depends on the model that is used to calculate the pair-correlation function. This confirms that the effect of quantum statistics on the index of refraction is dominant in this regime.

19.
Ann Oncol ; 26(5): 865-872, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25070543

RESUMO

BACKGROUND: The use of potential surrogate end points for overall survival, such as disease-free survival (DFS) or time-to-treatment failure (TTF) is increasingly common in randomized controlled trials (RCTs) in cancer. However, the definition of time-to-event (TTE) end points is rarely precise and lacks uniformity across trials. End point definition can impact trial results by affecting estimation of treatment effect and statistical power. The DATECAN initiative (Definition for the Assessment of Time-to-event End points in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for RCT in sarcomas and gastrointestinal stromal tumors (GIST). METHODS: We first carried out a literature review to identify TTE end points (primary or secondary) reported in publications of RCT. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points. Recommendations were developed through a validated consensus method formalizing the degree of agreement among experts. RESULTS: Recommended guidelines for the definition of TTE end points commonly used in RCT for sarcomas and GIST are provided for adjuvant and metastatic settings, including DFS, TTF, time to progression and others. CONCLUSION: Use of standardized definitions should facilitate comparison of trials' results, and improve the quality of trial design and reporting. These guidelines could be of particular interest to research scientists involved in the design, conduct, reporting or assessment of RCT such as investigators, statisticians, reviewers, editors or regulatory authorities.


Assuntos
Determinação de Ponto Final/normas , Tumores do Estroma Gastrointestinal/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Projetos de Pesquisa/normas , Sarcoma/terapia , Terminologia como Assunto , Consenso , Técnica Delphi , Progressão da Doença , Intervalo Livre de Doença , Determinação de Ponto Final/classificação , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/mortalidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/classificação , Sarcoma/diagnóstico , Sarcoma/mortalidade , Fatores de Tempo , Falha de Tratamento
20.
Poult Sci ; 94(8): 1751-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26049795

RESUMO

Previous research has shown that red light conditions may improve growth and decrease aggressive behaviors in chickens and turkeys; however, more recent studies suggest that blue-green light may improve production of broilers over red light. To date, no research has been conducted to examine whether different wavelengths of light have an impact on production in the Pekin duck. To determine this, we raised Pekin ducks under aviary conditions that were similar to standard commercial barns. The ducks were kept in 3 different pens: red light (approximately 625 nm), blue light (approximately 425 nm), and white light. Light sources in each pen were standardized to produce a peak energy at 1.6 × 10³ µM photons/m²/s at the level of the ducks' heads. Ducks were given ad libitum access to water and commercial duck diet, and were housed on pine shavings at a density of 0.43 m²/duck. Ducks were evaluated weekly for BW and condition and a subjective measure of the duck's anxiety levels was determined. We found that ducks housed under blue light had significantly (P < 0.01) reduced BW at every age until the end of the study (processing age; 35 d). Unlike ducks housed under red or white light, ducks housed in the blue pen showed a higher level of anxiety; while evaluators were in the pen a majority of them began panting, they were much less inquisitive than other ducks, they took longer to exhibit normal social behavior once evaluation was completed, and they frequently "swarmed" when no people were present. There were no differences in any measurements between the red and white-lighted pens. These data suggest that unlike the chicken, blue lights may be inappropriate for raising Pekin ducks in a commercial setting.


Assuntos
Comportamento Animal/fisiologia , Patos/fisiologia , Iluminação/instrumentação , Envelhecimento , Animais , Composição Corporal , Cor , Abrigo para Animais
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