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1.
CA Cancer J Clin ; 66(4): 326-36, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26594835

RESUMO

Imaging has traditionally played a minor role in the diagnosis and staging of prostate cancer. However, recent controversies generated by the use of prostate-specific antigen (PSA) screening followed by random biopsy have encouraged the development of new imaging methods for prostate cancer. Multiparametric magnetic resonance imaging (mpMRI) has emerged as the imaging method best able to detect clinically significant prostate cancers and to guide biopsies. Here, the authors explain what mpMRI is and how it is used clinically, especially with regard to high-risk populations, and we discuss the impact of mpMRI on treatment decisions for men with prostate cancer. CA Cancer J Clin 2016;66:326-336. © 2015 American Cancer Society.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico , Medicina Baseada em Evidências , Guias como Assunto , Humanos , Masculino , Vigilância da População , Valor Preditivo dos Testes , Sensibilidade e Especificidade
2.
Support Care Cancer ; 29(11): 6505-6510, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33905012

RESUMO

INTRODUCTION: Nausea, vomiting, constipation, and diarrhea are common cancer and cancer therapy adverse effects. Pharmacists are uniquely positioned to optimize patient symptom control and minimize excess use of hospital resources, such as emergency department visits. METHODS: Michigan Medicine oncology clinical pharmacists have been independently providing patient symptom management through a collaborative drug therapy management (CDTM) program which established guidelines for management of gastrointestinal toxicities (nausea, vomiting, diarrhea, and/or constipation) secondary to a patient's cancer diagnosis or treatment of the cancer. Patients were referred to the pharmacist by the treating oncologist or hematologist. RESULTS: From June 2019 to May 2020, there were a total of 62 patient referrals. Ten of the 62 referrals did not meet the CDTM inclusion criteria, resulting in 52 patients who were managed by the pharmacists. The total number of individual pharmacist visits was 136, with a median of 2.2 (range, 0-11) visits per patient referred. A total of 169 categorized pharmacist interventions were captured. Most interventions (100/169, 59.2%) were related to nausea/vomiting. Diarrhea-related and constipation-related interventions accounted for 10 (5.9%) and 13 (7.7%) of the total interventions, respectively. Most patients (36/52, 69.2%) had a reduction in the severity of their referral diagnosis symptom(s) based on Common Terminology Criteria for Adverse Events grading. CONCLUSION: The Michigan Medicine Pharmacist CDTM program allowed pharmacists to independently manage gastrointestinal toxicities of patients with cancer and improved patient symptom severity. The CDTM program has the opportunity to improve quality of care.


Assuntos
Conduta do Tratamento Medicamentoso , Farmacêuticos , Humanos , Oncologia , Cuidados Paliativos , Vômito/induzido quimicamente , Vômito/tratamento farmacológico
3.
Magn Reson Med ; 77(5): 1987-1995, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27279574

RESUMO

PURPOSE: The sensitivity of the magnetization transfer ratio (MTR) and apparent diffusion coefficient (ADC) for early detection of brain metastases was investigated in mice and humans. METHODS: Mice underwent MRI twice weekly for up to 31 d following intracardiac injection of the brain-homing breast cancer cell line MDA-MB231-BR. Patients with small cell lung cancer underwent quarterly MRI for 1 year. MTR and ADC were measured in regions of metastasis and matched contralateral tissue at the final time point and in registered regions at earlier time points. Texture analysis and linear discriminant analysis were performed to detect metastasis-containing slices. RESULTS: Compared with contralateral tissue, mouse metastases had significantly lower MTR and higher ADC at the final time point. Some lesions were visible at earlier time points on the MTR and ADC maps: 24% of these were not visible on corresponding T2 -weighted images. Texture analysis using the MTR maps showed 100% specificity and 98% sensitivity for metastasis at the final time point, with 77% sensitivity 2-4 d earlier and 46% 5-8 d earlier. Only 2 of 16 patients developed metastases, and their penultimate scans were normal. CONCLUSIONS: Some brain metastases may be detected earlier on MTR than conventional T2 ; however, the small gain is unlikely to justify "predictive" MRI. Magn Reson Med 77:1987-1995, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Carcinoma de Pequenas Células do Pulmão/diagnóstico por imagem , Idoso , Animais , Linhagem Celular Tumoral , Análise Discriminante , Detecção Precoce de Câncer , Feminino , Humanos , Modelos Lineares , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Metástase Neoplásica , Carcinoma de Pequenas Células do Pulmão/patologia
4.
J Magn Reson Imaging ; 45(2): 579-585, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27391860

RESUMO

PURPOSE: Multiparametric MRI (mpMRI) improves the detection of clinically significant prostate cancer, but is limited by interobserver variation. The second version of theProstate Imaging Reporting and Data System (PIRADSv2) was recently proposed as a standard for interpreting mpMRI. To assess the performance and interobserver agreement of PIRADSv2 we performed a multi-reader study with five radiologists of varying experience. MATERIALS AND METHODS: Five radiologists (n = 2 prostate dedicated, n = 3 general body) blinded to clinicopathologic results detected and scored lesions on prostate mpMRI using PIRADSv2. The endorectal coil 3 Tesla MRI included T2W, diffusion-weighted imaging (apparent diffusion coefficient, b2000), and dynamic contrast enhancement. Thirty-four consecutive patients were included. Results were correlated with radical prostatectomy whole-mount histopathology produced with patient-specific three-dimensional molds. An index lesion was defined on pathology as the lesion with highest Gleason score or largest volume if equivalent grades. Average sensitivity and positive predictive values (PPVs) for all lesions and index lesions were determined using generalized estimating equations. Interobserver agreement was evaluated using index of specific agreement. RESULTS: Average sensitivity was 91% for detecting index lesions and 63% for all lesions across all readers. PPV was 85% for PIRADS ≥ 3 and 90% for PIRADS ≥ 4. Specialists performed better only for PIRADS ≥ 4 with sensitivity 90% versus 79% (P = 0.01) for index lesions. Index of specific agreement among readers was 93% for the detection of index lesions, 74% for the detection of all lesions, and 85% for scoring index lesions, and 58% for scoring all lesions. CONCLUSION: By using PIRADSv2, general body radiologists and prostate specialists can detect high-grade index prostate cancer lesions with high sensitivity and agreement. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:579-585.


Assuntos
Imagem de Difusão por Ressonância Magnética/normas , Interpretação de Imagem Assistida por Computador/normas , Guias de Prática Clínica como Assunto , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Radiologia/normas , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
5.
Magn Reson Med ; 75(4): 1708-16, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25995019

RESUMO

PURPOSE: Ultrasound-guided fine needle aspirate cytology fails to diagnose many malignant thyroid nodules; consequently, patients may undergo diagnostic lobectomy. This study assessed whether textural analysis (TA) could noninvasively stratify thyroid nodules accurately using diffusion-weighted MRI (DW-MRI). METHODS: This multi-institutional study examined 3T DW-MRI images obtained with spin echo echo planar imaging sequences. The training data set included 26 patients from Cambridge, United Kingdom, and the test data set included 18 thyroid cancer patients from Memorial Sloan Kettering Cancer Center (New York, New York, USA). Apparent diffusion coefficients (ADCs) were compared over regions of interest (ROIs) defined on thyroid nodules. TA, linear discriminant analysis (LDA), and feature reduction were performed using the 21 MaZda-generated texture parameters that best distinguished benign and malignant ROIs. RESULTS: Training data set mean ADC values were significantly different for benign and malignant nodules (P = 0.02) with a sensitivity and specificity of 70% and 63%, respectively, and a receiver operator characteristic (ROC) area under the curve (AUC) of 0.73. The LDA model of the top 21 textural features correctly classified 89/94 DW-MRI ROIs with 92% sensitivity, 96% specificity, and an AUC of 0.97. This algorithm correctly classified 16/18 (89%) patients in the independently obtained test set of thyroid DW-MRI scans. CONCLUSION: TA classifies thyroid nodules with high sensitivity and specificity on multi-institutional DW-MRI data sets. This method requires further validation in a larger prospective study. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Área Sob a Curva , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
6.
Acta Radiol ; 57(11): 1396-1401, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26013022

RESUMO

Background A variety of magnetic resonance (MR) lymphographic agents have been proposed for mapping the lymph nodes draining the prostate. Purpose To investigate the feasibility of using ferumoxytol (an FDA-approved iron oxide agent) for lymph node mapping of the prostate on imaging (MRI) in a non-human primate (NHP) Macaque model. Material and Methods Four NHPs weighing 5-13 kg underwent injection of ferumoxytol after a needle was introduced transrectally under MRI guidance into the prostate using a commercially available intrarectal MRI biopsy guide. Ferumoxytol was administered at dosage in the range of 0.15-0.75 mg Fe/kg in a fixed injection volume of 0.2 mL. T1-weighted MRI was performed at 3 T starting immediately and extending at least 45 min post-injection. Two readers evaluated the images in consensus. The NHPs tolerated the ferumoxytol injections at all doses with no evident side effects. Results It was determined that the lowest dose of 0.15 mg Fe/kg produced the best outcome in terms of lymph node visualization and draining nodes were reliably visualized at this dose and volume. Conclusion Thus, MRI with intraprostatic injection of ferumoxytol may be considered an effective T1 contrast agent for prospective mapping of lymph nodes draining the prostate and, thus, for attempted sentinel lymph node identification in prostate cancer. Large clinical trials to determine safety and efficacy are needed.


Assuntos
Óxido Ferroso-Férrico/administração & dosagem , Aumento da Imagem/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/secundário , Linfonodo Sentinela/diagnóstico por imagem , Animais , Meios de Contraste/administração & dosagem , Estudos de Viabilidade , Humanos , Injeções Intralesionais , Metástase Linfática , Macaca mulatta , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Curr Urol Rep ; 16(5): 30, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25773350

RESUMO

Nodal staging is important in prostate cancer treatment. While surgical lymph node dissection is the classic method of determining whether lymph nodes harbor malignancy, this is a very invasive technique. Current noninvasive approaches to identifying malignant lymph nodes are limited. Conventional imaging methods rely on size and morphology of lymph nodes and have notoriously low sensitivity for detecting malignant nodes. New imaging techniques such as targeted positron emission tomography (PET) imaging and magnetic resonance lymphography (MRL) with iron oxide particles are promising for nodal staging of prostate cancer. In this review, the strengths and limitations of imaging techniques for lymph node staging of prostate cancer are discussed.


Assuntos
Imagem Multimodal/métodos , Estadiamento de Neoplasias/métodos , Neoplasias da Próstata/secundário , Humanos , Metástase Linfática , Masculino , Neoplasias da Próstata/diagnóstico
8.
Abdom Imaging ; 40(7): 2557-65, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25916869

RESUMO

PURPOSE: The posterior subcapsular region of the prostate is often undersampled by transrectal ultrasound (TRUS)-guided biopsy. The close proximity of these lesions to the posterior capsular wall of the prostate makes them difficult to localize while increasing the need for early detection because of their increased risk for extracapsular extension. We retrospectively evaluated the multiparametric MRI (mpMRI) features of subcapsular prostate cancers to make radiologists more aware of this condition. MATERIALS AND METHODS: Between January 2010 and July 2014, all patients referred for 3T mpMRI and subsequent MR-US Fusion-guided biopsy (FgBx) and systematic 12-core sextant biopsy (SBx) under an IRB approved protocol, were reviewed, and imaging confirmed subcapsular prostate cancers were identified. Subcapsular lesions were defined as thin lesions that were just inside the prostate capsule. Matching patient demographics and clinical findings including age, PSA, PSA density, whole prostate volume, history of prostate cancer, Gleason score, and clinical management were tabulated. RESULTS: Of 992 eligible patients, 33 patients had subcapsular lesions in the prostate detected by mpMRI. Mean age, PSA, and prostate volume in this group were 63 years (range: 52-76 years), 8.4 ng/mL (range: 1.22-65.20), and 53 mL (range: 12-125 mL), respectively. The combination biopsy (SBx + FgBx) confirmed prostate cancer in 24 of 33 patients (72.7%) and in 9 patients the biopsy was negative. Of the 24 cancers, 19 were confirmed on both FgBx and conventional biopsy; however, 5 cancers were only detected on FgBx. In 4 of the 19 patients in which both biopsy methods were positive, the FgBx yielded a higher Gleason score. CONCLUSION: Subcapsular lesions on mpMRI are relatively infrequent but are usually malignant. Although the majority are confirmed on conventional 12-core biopsies, about 20% of these lesions require FgBx for diagnosis, and FgBx more accurately grades the lesions in another 20%. Thus, FgBx is of considerable benefit in confirming the diagnosis of subcapsular prostate cancer despite their proximity to the prostatic capsule.


Assuntos
Imagem por Ressonância Magnética Intervencionista , Imagem Multimodal , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Ultrassonografia de Intervenção , Idoso , Biópsia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Próstata/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
9.
Abdom Imaging ; 40(6): 1788-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25596716

RESUMO

Prostate cancer is a common malignancy in the United States that results in over 30,000 deaths per year. The current state of prostate cancer diagnosis, based on PSA screening and sextant biopsy, has been criticized for both overdiagnosis of low-grade tumors and underdiagnosis of clinically significant prostate cancers (Gleason score ≥7). Recently, image guidance has been added to perform targeted biopsies of lesions detected on multi-parametric magnetic resonance imaging (mpMRI) scans. These methods have improved the ability to detect clinically significant cancer, while reducing the diagnosis of low-grade tumors. Several approaches have been explored to improve the accuracy of image-guided targeted prostate biopsy, including in-bore MRI-guided, cognitive fusion, and MRI/transrectal ultrasound fusion-guided biopsy. This review will examine recent advances in these image-guided targeted prostate biopsy techniques.


Assuntos
Próstata/patologia , Neoplasias da Próstata/diagnóstico , Humanos , Biópsia Guiada por Imagem , Imagem por Ressonância Magnética Intervencionista , Masculino , Ultrassonografia de Intervenção
10.
Abdom Imaging ; 40(8): 3222-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26239399

RESUMO

PURPOSE: (18)F-FDG PET/CT is used to characterize many malignancies, but is not recommended for localized prostate cancer. This study explores the value of multi-parametric MRI (mpMRI) in characterizing incidental prostate (18)F-FDG uptake. METHODS: Thirty-one patients who underwent (18)F-FDG PET/CT for reasons unrelated to prostate cancer and prostate mpMRI were eligible for this retrospective study. The mpMRI included T2-weighted (T2W), dynamic contrast enhancement (DCE), apparent diffusion coefficient (ADC), and MR spectroscopy (MRS) sequences. Fourteen patients were excluded (n = 8 insufficient histopathology, n = 6 radical prostatectomy before PET), and final analysis included 17 patients. A nuclear medicine physician, blinded to clinicopathologic findings, identified suspicious areas and maximum standardized uptake values (SUV max) on (18)F-FDG PET/CT. Sector-based imaging findings were correlated with annotated histopathology from whole-mount or MRI/transrectal ultrasound fusion biopsy samples. Positive predictive values (PPVs) were estimated using generalized estimating equations with logit link. Results were evaluated with Kruskal-Wallis and Dunn's multiple comparisons tests. RESULTS: The PPV of (18)F-FDG PET alone in detecting prostate cancer was 0.65. Combining (18)F-FDG PET as a base parameter with mpMRI (T2W, DCE, ADC, and MRS) increased the PPV to 0.82, 0.83, 0.83, and 0.94, respectively. All benign lesions had SUV max < 6. Malignant lesions had higher SUV max values that correlated with Gleason scores. There was a significant difference in SUV max per prostate between the Gleason ≥ 4 + 5 and benign categories (p = 0.03). CONCLUSIONS: Focal incidental prostate (18)F-FDG uptake has low clinical utility alone, but regions of uptake may harbor high-grade prostate cancer, especially if SUV max > 6. Using mpMRI to further evaluate incidental (18)F-FDG uptake aids the diagnosis of prostate cancer.


Assuntos
Fluordesoxiglucose F18 , Achados Incidentais , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/patologia , Tomografia Computadorizada por Raios X , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Compostos Radiofarmacêuticos , Estudos Retrospectivos
11.
Artigo em Inglês | MEDLINE | ID: mdl-38437924

RESUMO

PURPOSE: Patients' understanding of radiation therapy (RT) and data regarding optimal approaches to patient education (PE) within radiation oncology (RO) are limited. We aimed to evaluate PE practices of radiation oncologists and interprofessional RT care team members to inform recommendations for delivering inclusive and accessible PE. METHODS AND MATERIALS: An anonymous survey was administered to all Radiation Oncology Education Collaborative Study Group members (10/5/22-11/23/22). Respondent demographics, individual practices/preferences, and institutional practices were collected. Qualitative items explored strategies, challenges, and desired resources for PE. Descriptive statistics summarized survey responses. The Fisher exact test compared PE practices by respondent role and PE timing. Thematic analysis was used for qualitative responses. RESULTS: One hundred thirteen Radiation Oncology Education Collaborative Study Group members completed the survey (28.2% response rate); RO attendings comprised 68.1% of respondents. Most practiced in an academic setting (85.8%) in North America (80.5%). Institution-specific materials were the most common PE resource used by radiation oncologists (67.6%). Almost half (40.2%) reported that their PE practices differed based on clinical encounter type, with paper handouts commonly used for in-person and multimedia for telehealth visits. Only 57.7% reported access to non-English PE materials. PE practices among radiation oncologists differed according to RT clinical workflow timing (consultation versus simulation versus first RT, respectively): one-on-one teaching: 88.5% versus 49.4% versus 56.3%, P < .01, and paper handouts: 69.0% versus 28.7% versus 16.1%, P < .01. Identified challenges for PE delivery included limited time, administrative barriers to the development or implementation of new materials or practices, and a lack of customized resources for tailored PE. Effective strategies for PE included utilization of visual diagrams, multimedia, and innovative education techniques to personalize PE delivery/resources for a diverse patient population, as well as fostering interprofessional collaboration to reinforce educational content. CONCLUSIONS: Radiation oncologists and interprofessional RO team members engage in PE, with most using institution-specific materials often available only in English. PE practices differ according to clinical encounter type and RT workflow timing. Increased adoption of multimedia materials and partnerships with patients to tailor PE resources are needed to foster high-quality, patient-centered PE delivery.

12.
Crit Rev Oncol Hematol ; 148: 102897, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32109715

RESUMO

Advanced classical Hodgkin lymphoma (cHL) is a rare lymphoid disease characterized by the presence of Hodgkin and Reed-Sternberg (HRS) cells. Each year, cHL accounts for 0.5% of all new cancer diagnoses and about 80% are diagnosed with advanced stage disease. Given the significant improvement in cure rates, the focus of treatment has shifted towards minimization of acute and long-term toxicities. PET-adapted strategies have largely been adopted as standard of care in the United States in an attempt to balance toxicities with adequate lymphoma control. However, the appropriate upfront chemotherapy regimen (ABVD versus eBEACOPP) remains controversial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Doença de Hodgkin/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bleomicina/administração & dosagem , Ciclofosfamida/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/patologia , Humanos , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Resultado do Tratamento , Vimblastina/administração & dosagem , Vincristina/administração & dosagem
13.
Leuk Lymphoma ; 61(5): 1126-1132, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31876206

RESUMO

The CALGB/Alliance 50303 trial found a fivefold increase in the rate of severe neuropathies with DA-EPOCH-R compared to R-CHOP. A likely cause is a higher, uncapped dose of vincristine which is unique to DA-EPOCH-R. Due to a potential for increased toxicity and a paucity of literature confirming improved efficacy with higher vincristine doses, our institution implemented a 2 mg vincristine dose cap with DA-EPOCH-R. We conducted a single-center, retrospective cohort study assessing rates of neuropathy in patients receiving DA-EPOCH-R with or without a 2 mg vincristine dose cap. Patients who received a 2 mg vincristine dose cap had a significant reduction in the incidence of grade 2+ neuropathy (40.9% vs. 84.1%, p = .001) and a significantly longer time to onset of grade 2+ neuropathy (not reached vs. 63 days, p = .001). A vincristine dose cap of 2 mg per cycle may reduce the neurotoxicity-associated morbidity of DA-EPOCH-R.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfoma Difuso de Grandes Células B , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Etoposídeo/uso terapêutico , Humanos , Incidência , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Prednisona/uso terapêutico , Estudos Retrospectivos , Rituximab/uso terapêutico , Vincristina/efeitos adversos
14.
Cell Calcium ; 41(3): 195-206, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16914200

RESUMO

We have used single cell fluorescence imaging techniques to examine how functional properties of the caffeine-sensitive Ca(2+) store change during differentiation of a sub-population of caffeine-sensitive SH-SY5Y cells. Application of caffeine (30 mM) 1-10.5 min after a 'priming' depolarisation pulse of 55 mM K(+) revealed that the caffeine-sensitive store in undifferentiated cells remained replete, whereas that in 9-cis retinoic acid (9cRA)-differentiated cells spontaneously dissipated with a t(1/2) of 2.8 min, and was essentially completely depleted approximately 10 min after priming. In 9cRA-differentiated cells that were stimulated with methacholine (10 microM) 1 min after priming, the amplitude, rate of rise and propagation velocity of the Ca(2+) wave in the neurites were all constant, whereas these kinetic parameters all progressively decreased as the wave travelled along the neurites in cells that were stimulated 10 min after priming. Use-dependent block with ryanodine inhibited the global Ca(2+) signal in 9cRA-differentiated cells stimulated with methacholine 1 min after priming (71+/-8%) but not 10 min after priming. Depolarisation was more effective at priming the caffeine-sensitive Ca(2+) store in 9cRA-differentiated cells, which lack a functional store-operated Ca(2+) entry pathway. We conclude that differentiation of caffeine-sensitive SH-SY5Y cells is accompanied by an increase in lability of the caffeine-sensitive Ca(2+) store, and that spontaneous dissipation of Ca(2+) from the store limits the time course of its molecular 'memory' during which it can amplify the hormone-induced Ca(2+) signal by Ca(2+)-induced Ca(2+) release.


Assuntos
Cafeína/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Neuroblastoma/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Potenciais da Membrana/efeitos dos fármacos , Cloreto de Metacolina/farmacologia , Microscopia de Fluorescência , Neuritos/metabolismo , Parassimpatomiméticos/farmacologia , Potássio/metabolismo , Potássio/farmacologia , Tretinoína/farmacologia
15.
Biochem J ; 388(Pt 3): 941-8, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15673285

RESUMO

We have investigated effects of neuronal differentiation on hormone-induced Ca2+ entry. Fura-2 fluorescence measurements of undifferentiated SH-SY5Y neuroblastoma cells, stimulated with methacholine, revealed the presence of voltage-operated Ca2+-permeable, Mn2+-impermeable entry pathways, and at least two voltage-independent Ca2+- and Mn2+-permeable entry pathways, all of which apparently contribute to both peak and plateau phases of the Ca2+ signal. Similar experiments using 9-cis retinoic acid-differentiated cells, however, revealed voltage-operated Ca2+-permeable, Mn2+-impermeable channels, and, more significantly, the absence or down-regulation of the most predominant of the voltage-independent entry pathways. This down-regulated pathway is probably due to CCE (capacitative Ca2+ entry), since thapsigargin also stimulated Ca2+ and Mn2+ entry in undifferentiated but not differentiated cells. The Ca2+ entry components remaining in methacholine-stimulated differentiated cells contributed to only the plateau phase of the Ca2+ signal. We conclude that differentiation of SH-SY5Y cells results in a mechanistic and functional change in hormone-stimulated Ca2+ entry. In undifferentiated cells, voltage-operated Ca2+ channels, CCE and NCCE (non-CCE) pathways are present. Of the voltage-independent pathways, the predominant one appears to be CCE. These pathways contribute to both peak and plateau phases of the Ca2+ signal. In differentiated cells, CCE is either absent or down-regulated, whereas voltage-operated entry and NCCE remain active and contribute to only the plateau phase of the Ca2+ signal.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Neuroblastoma/metabolismo , Neurônios/efeitos dos fármacos , Tretinoína/farmacologia , Canais de Cálcio/metabolismo , Cátions Bivalentes/metabolismo , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , Manganês/metabolismo , Cloreto de Metacolina/farmacologia , Agonistas Muscarínicos/farmacologia , Neuroblastoma/patologia , Neurônios/citologia , Neurônios/metabolismo , Tapsigargina/farmacologia
16.
Abdom Radiol (NY) ; 41(5): 844-53, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27193787

RESUMO

DCE MRI is an established component of multi-parametric MRI of the prostate. The sequence highlights the vascularization of cancerous lesions, allowing readers to corroborate suspicious findings on T2W and DW MRI and to note subtle lesions not visible on the other sequences. In this article, we review the technical aspects, methods of evaluation, limitations, and future perspectives of DCE MRI.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Biópsia Guiada por Imagem , Masculino , Neoplasias da Próstata/patologia
17.
Magn Reson Imaging ; 34(9): 1227-1234, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27451403

RESUMO

PURPOSE: The aim of this proof-of-concept work is to propose an unsupervised framework that combines multiple parameters, in "positive-if-all-positive" manner, from different models to localize tumors. METHODS: A voxel-by-voxel analysis of the DW-MRI images of whole prostate was performed to obtain parametric maps for D*, D, f, and K using the IVIM and kurtosis models. Ten patients with moderate or high-risk prostate cancer were included in study. The mean age and serum PSA for these 10 patients were 65years (range 54-78) and 21.9ng/mL (range 4.84-44.81), respectively. These patients were scanned using a DW spin-echo sequence with echo-planar readout with 16 equidistantly spaced b-values in the range of 0-2000s/mm2 (TE=58ms; TR=3990ms; spatial resolution 2.19×2.19×2.73mm3, slices =26, FOV=140×140mm, slice gap =0.27mm, NSA=2). RESULTS: The proposed framework detected 24 lesions of which 14 were true positive with 58% tumor detection rate on lesion-based analysis with sensitivity of 100%. The mpMRI evaluation (PIRADSv2) identified 12 of 14 true positive lesions with sensitivity of 86%; positive predictive value of mpMRI was 92%. The index lesions were visible on all framework maps and were coded as the most suspicious in 9 of 10 patients. CONCLUSION: Preliminary results of the proposed framework indicate high patient-based sensitivity with 100% detection rate for identifying moderate-high risk aggressive index lesions.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Urology ; 88: 125-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26680244

RESUMO

OBJECTIVE: To validate the use of biparametric (T2- and diffusion-weighted) magnetic resonance imaging (B-MRI) and prostate-specific antigen (PSA) or PSA density (PSAD) in a biopsy-naive cohort at risk for prostate cancer (PCa). METHODS: All patients (n = 59) underwent PSA screening and digital rectal exam prior to a B-MRI followed by MRI or transrectal ultrasound fusion-guided targeted biopsy. Previously reported composite formulas incorporating screen positive lesions (SPL) on B-MRI and PSA or PSAD were developed to maximize PCa detection. For PSA, a patient was considered screen positive if PSA level + 6 × (the number of SPL) >14. For PSAD, screening was positive if PSAD × 14 + (the number of SPL) >4.25. These schemes were employed in this new test set to validate the initial formulas. Performance assessment of these formulas was determined for all cancer detection and for tumors with Gleason ≥3 + 4. RESULTS: Screen positive lesions on B-MRI had the highest sensitivity (95.5%) and negative predictive value of 71.4% compared with PSA and PSAD. B-MRI significantly improved sensitivity (43.2-72.7%, P = .0002) when combined with PSAD. The negative predictive value of PSA increased with B-MRI, achieving 91.7% for B-MRI and PSA for Gleason ≥3 + 4. Overall accuracies of the composite equations were 81.4% (B-MRI and PSA) and 78.0% (B-MRI and PSAD). CONCLUSION: Validation with a biopsy-naive cohort demonstrates the parameter SPL performed better than PSA or PSAD alone in accurately detecting PCa. The combined use of B-MRI, PSA, and PSAD resulted in improved accuracy for detecting clinically significant PCa.


Assuntos
Imageamento por Ressonância Magnética/métodos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Cell Calcium ; 38(2): 111-20, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16095688

RESUMO

We have used single cell fluorescence imaging techniques to examine the role that ryanodine receptors play in the stimulus-induced Ca(2+) responses of SH-SY5Y cells. The muscarinic agonist methacholine (1mM) resulted in a Ca(2+) signal in 95% of all cells. Caffeine (30 mM) however stimulated a Ca(2+) signal in only 1-7% of N-type (neuroblastic) cells within any given field. The caffeine response was independent of extracellular Ca(2+), regenerative in nature, and abolished in a use-dependent fashion by ryanodine. In caffeine-responsive cells, the magnitude of the methacholine-induced Ca(2+) signal was inhibited by 75.07 +/- 5.51% by pretreatment with caffeine and ryanodine, suggesting that the caffeine-sensitive store may act as a Ca(2+) source after muscarinic stimulation. When these data were combined with equivalent data from non-caffeine-responsive cells, the degree of apparent inhibition was significantly reduced. In contrast, after store depletion by caffeine, the Ca(2+) signal induced by 55 mM K(+) was potentiated 2.5-fold in the presence of ryanodine, suggesting that the store may act a Ca(2+) sink after depolarisation. We conclude that a caffeine- and ryanodine-sensitive store can act as a Ca(2+) source and sink in SH-SY5Y cells, and that effects of the store can become obscured if data from caffeine-insensitive cells are not excluded.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Líquido Intracelular/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Cafeína/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Líquido Extracelular/metabolismo , Fura-2 , Humanos , Líquido Intracelular/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Cloreto de Metacolina/farmacologia , Agonistas Muscarínicos/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Potássio/metabolismo , Potássio/farmacologia , Rianodina/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Células Tumorais Cultivadas
20.
Clin Vaccine Immunol ; 22(7): 711-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25924765

RESUMO

Clostridium difficile infection (CDI) is the principal cause of nosocomial diarrhea and pseudomembranous colitis associated with antibiotic therapy. Recent increases in the number of outbreaks attributed to highly virulent antibiotic-resistant strains underscore the importance of identifying efficacious alternatives to antibiotics to control this infection. CDI is mediated by two large exotoxins, toxins A and B. Strong humoral toxin-specific immune responses are associated with recovery and a lack of disease recurrence, whereas insufficient humoral responses are associated with recurrent CDI. Multiple approaches targeting these toxins, including intravenous immunoglobulin, neutralizing polymers, active vaccines, and, most recently, monoclonal antibodies (MAbs), have been explored, with various degrees of success. In this study, we describe the characterization of the first MAbs isolated from healthy human donors using a high-throughput B-cell cloning strategy. The MAbs were selected based on their ability to inhibit the actions of toxins A and B in vitro and because of their in vivo efficacy in a hamster challenge model. A potent 2-MAb cocktail was identified and then further potentiated by the addition of a second anti-toxin B MAb. This 3-MAb combination protected animals against mortality and also reduced the severity and duration of diarrhea associated with challenge with highly virulent strains of C. difficile toxinotypes 0 and III. This highly efficacious cocktail consists of one MAb specific to the receptor binding domain of toxin A and two MAbs specific to nonoverlapping regions of the glucosyltransferase domain of toxin B. This MAb combination offers great potential as a nonantibiotic treatment for the prevention of recurrent CDI.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Proteínas de Bactérias/antagonistas & inibidores , Toxinas Bacterianas/antagonistas & inibidores , Clostridioides difficile/imunologia , Infecções por Clostridium/prevenção & controle , Diarreia/prevenção & controle , Enterotoxinas/antagonistas & inibidores , Animais , Anticorpos Antibacterianos/administração & dosagem , Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Antitoxinas/administração & dosagem , Antitoxinas/imunologia , Infecções por Clostridium/imunologia , Infecções por Clostridium/patologia , Diarreia/imunologia , Diarreia/patologia , Modelos Animais de Doenças , Feminino , Humanos , Mesocricetus , Análise de Sobrevida , Resultado do Tratamento
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