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2.
Urologe A ; 61(4): 428-440, 2022 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-35389061

RESUMO

Multiparametric magnetic resonance imaging (mpMRI) is an integral component of prostate cancer diagnostics. According to the S3 guidelines on prostate cancer, mpMRI should be used for the primary diagnostics of prostate cancer as well as in active surveillance (AS). Basically, mpMRI consists of high-resolution T2-weighted (T2w) sequences, diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) sequences, which in turn are the basis for structured reporting according to the prostate imaging reporting and data system (PI-RADS) classification.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos
3.
Rofo ; 194(9): 983-992, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35272360

RESUMO

BACKGROUND: Until today, assessment of renal function has remained a challenge for modern medicine. In many cases, kidney diseases accompanied by a decrease in renal function remain undetected and unsolved, since neither laboratory tests nor imaging diagnostics provide adequate information on kidney status. In recent years, developments in the field of functional magnetic resonance imaging with application to abdominal organs have opened new possibilities combining anatomic imaging with multiparametric functional information. The multiparametric approach enables the measurement of perfusion, diffusion, oxygenation, and tissue characterization in one examination, thus providing more comprehensive insight into pathophysiological processes of diseases as well as effects of therapeutic interventions. However, application of multiparametric fMRI in the kidneys is still restricted mainly to research areas and transfer to the clinical routine is still outstanding. One of the major challenges is the lack of a standardized protocol for acquisition and postprocessing including efficient strategies for data analysis. This article provides an overview of the most common fMRI techniques with application to the kidney together with new approaches regarding data analysis with deep learning. METHODS: This article implies a selective literature review using the literature database PubMed in May 2021 supplemented by our own experiences in this field. RESULTS AND CONCLUSION: Functional multiparametric MRI is a promising technique for assessing renal function in a more comprehensive approach by combining multiple parameters such as perfusion, diffusion, and BOLD imaging. New approaches with the application of deep learning techniques could substantially contribute to overcoming the challenge of handling the quantity of data and developing more efficient data postprocessing and analysis protocols. Thus, it can be hoped that multiparametric fMRI protocols can be sufficiently optimized to be used for routine renal examination and to assist clinicians in the diagnostics, monitoring, and treatment of kidney diseases in the future. KEY POINTS: · Multiparametric fMRI is a technique performed without the use of radiation, contrast media, and invasive methods.. · Multiparametric fMRI provides more comprehensive insight into pathophysiological processes of kidney diseases by combining functional and structural parameters.. · For broader acceptance of fMRI biomarkers, there is a need for standardization of acquisition, postprocessing, and analysis protocols as well as more prospective studies.. · Deep learning techniques could significantly contribute to an optimization of data acquisition and the postprocessing and interpretation of larger quantities of data.. CITATION FORMAT: · Zhang C, Schwartz M, Küstner T et al. Multiparametric Functional MRI of the Kidney: Current State and Future Trends with Deep Learning Approaches. Fortschr Röntgenstr 2022; 194: 983 - 992.


Assuntos
Aprendizado Profundo , Nefropatias , Imageamento por Ressonância Magnética Multiparamétrica , Humanos , Rim/fisiologia , Imageamento por Ressonância Magnética , Estudos Prospectivos
4.
Radiologe ; 61(5): 433-439, 2021 May.
Artigo em Alemão | MEDLINE | ID: mdl-33830326

RESUMO

CLINICAL/METHODICAL ISSUE: The carpal joint is one of the most complex joints in the body comprising multiple bones that allow flexibility while simultaneously providing stability. Variations in osseous structures that may be either cause or result of pathological changes may make radiological reporting challenging. Only the knowledge of important osseous variations allows a reliable assessment of carpal imaging studies. STANDARD RADIOLOGICAL METHODS: The standard imaging technique for evaluation of osseous carpal structures is conventional radiography, which is followed by computed tomography (CT) and-under special circumstances-magnetic resonance imaging (MRI). Other imaging methods such as sonography or nuclear medicine studies do not play a significant role in clinical routine. METHODICAL INNOVATIONS: Apart from continuous reduction in effective radiation dose, there have been no significant methodical improvements in the past decade regarding imaging of osseous carpal structures in clinical routine. PRACTICAL RECOMMENDATIONS: As the initial diagnostic procedure, conventional radiography usually allows a safe and reliable diagnosis of osseous structures. Unclear or discrepant imaging findings between clinical and imaging assessment should initiate further imaging, preferably with CT. Only for certain questions or to reduce effective radiation dose in children MRI studies should be performed in clinical routine.


Assuntos
Articulação do Punho , Punho , Criança , Humanos , Imageamento por Ressonância Magnética , Radiografia , Tomografia Computadorizada por Raios X , Articulação do Punho/diagnóstico por imagem
5.
Eur J Endocrinol ; 176(2): 123-132, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27913606

RESUMO

OBJECTIVE: To compare the effects of acyl ghrelin (AG) and desacyl ghrelin (DAG) on blood pressure (BP), heart rate (HR) and other autonomic parameters in healthy humans and to elucidate the hormonal mechanisms through which AG could exert its cardiovascular effects. DESIGN: Seventeen healthy participants underwent frequent monitoring of systolic (sBP) and diastolic blood pressure (dBP), HR, respiratory rate (RR) and body surface temperature (Temp) during continuous infusion of AG, DAG, combined AG + DAG or saline control before and during an IV glucose tolerance test on 4 separate days. Plasma catecholamines, renin and aldosterone levels were also measured. Differences in outcome measures between treatment groups were assessed using mixed-model analysis. RESULTS: Compared to the saline control, AG and combined AG + DAG infusions decreased sBP, dBP, mean arterial blood pressure (MAP), HR and Temp. In contrast, DAG infusion did not alter BP, RR or Temp, but did decrease HR. The AG and AG + DAG infusions also raised plasma aldosterone levels compared to saline (P < 0.001) without affecting renin or catecholamine levels. CONCLUSIONS: The decrease in BP, HR, RR and Temp with AG infusion suggests mediation through the autonomic nervous system. The lack of response to DAG suggests that these autonomic effects require activation of the ghrelin receptor.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Grelina/farmacologia , Acilação , Adulto , Anti-Hipertensivos/farmacologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão , Masculino , Pessoa de Meia-Idade , Temperatura , Resultado do Tratamento , Adulto Jovem
6.
Health Aff (Millwood) ; 35(4): 654-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27044966

RESUMO

Some experts contend that requiring patients to pay out of pocket for a portion of their care will bring consumer discipline to health care markets. But are physicians prepared to help patients factor out-of-pocket expenses into medical decisions? In this qualitative study of audiorecorded clinical encounters, we identified physician behaviors that stand in the way of helping patients navigate out-of-pocket spending. Some behaviors reflected a failure to fully engage with patients' financial concerns, from never acknowledging such concerns to dismissing them too quickly. Other behaviors reflected a failure to resolve uncertainty about out-of-pocket expenses or reliance on temporary solutions without making long-term plans to reduce spending. Many of these failures resulted from systemic barriers to health care spending conversations, such as a lack of price transparency. For consumer health care markets to work as intended, physicians need to be prepared to help patients navigate out-of-pocket expenses when financial concerns arise during clinical encounters.


Assuntos
Efeitos Psicossociais da Doença , Financiamento Pessoal/economia , Gastos em Saúde/ética , Relações Médico-Paciente , Padrões de Prática Médica/economia , Adulto , Comunicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Estados Unidos
7.
Med Decis Making ; 36(7): 900-10, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26785714

RESUMO

BACKGROUND: More than 1 in 4 Americans report difficulty paying medical bills. Cost-reducing strategies discussed during outpatient physician visits remain poorly characterized. OBJECTIVE: We sought to determine how often patients and physicians discuss health care costs during outpatient visits and what strategies, if any, they discussed to lower patient out-of-pocket costs. DESIGN: Retrospective analysis of dialogue from 1,755 outpatient visits in community-based practices nationwide from 2010 to 2014. The study population included 677 patients with breast cancer, 422 with depression, and 656 with rheumatoid arthritis visiting 56 oncologists, 36 psychiatrists, and 26 rheumatologists, respectively. RESULTS: Thirty percent of visits contained cost conversations (95% confidence interval [CI], 28 to 32). Forty-four percent of cost conversations involved discussion of cost-saving strategies (95% CI, 40 to 48; median duration, 68 s). We identified 4 strategies to lower costs without changing the care plan. They were, in order of overall frequency: 1) changing logistics of care, 2) facilitating co-pay assistance, 3) providing free samples, and 4) changing/adding insurance plans. We also identified 4 strategies to reduce costs by changing the care plan: 1) switching to lower-cost alternative therapy/diagnostic, 2) switching from brand name to generic, 3) changing dosage/frequency, and 4) stopping/withholding interventions. Strategies were relatively consistent across health conditions, except for switching to a lower-cost alternative (more common in breast oncology) and providing free samples (more common in depression). LIMITATION: Focus on 3 conditions with potentially high out-of-pocket costs. CONCLUSIONS: Despite price opacity, physicians and patients discuss a variety of out-of-pocket cost reduction strategies during clinic visits. Almost half of cost discussions mention 1 or more cost-saving strategies, with more frequent mention of those not requiring care-plan changes.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Redução de Custos , Financiamento Pessoal , Custos de Cuidados de Saúde , Visita a Consultório Médico/economia , Relações Médico-Paciente , Instituições de Assistência Ambulatorial/economia , Humanos
8.
J Immunol ; 191(6): 3410-8, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23935192

RESUMO

Sharks and skates represent the earliest vertebrates with an adaptive immune system based on lymphocyte Ag receptors generated by V(D)J recombination. Shark B cells express two classical Igs, IgM and IgW, encoded by an early, alternative gene organization consisting of numerous autonomous miniloci, where the individual gene cluster carries a few rearranging gene segments and one C region, µ or ω. We have characterized eight distinct Ig miniloci encoding the nurse shark ω H chain. Each cluster consists of VH, D, and JH segments and six to eight C domain exons. Two interspersed secretory exons, in addition to the 3'-most C exon with tailpiece, provide the gene cluster with the ability to generate at least six secreted isoforms that differ as to polypeptide length and C domain combination. All clusters appear to be functional, as judged by the capability for rearrangement and absence of defects in the deduced amino acid sequence. We previously showed that IgW VDJ can perform isotype switching to µ C regions; in this study, we found that switching also occurs between ω clusters. Thus, C region diversification for any IgW VDJ can take place at the DNA level by switching to other ω or µ C regions, as well as by RNA processing to generate different C isoforms. The wide array of pathogens recognized by Abs requires different disposal pathways, and our findings demonstrate complex and unique pathways for C effector function diversity that evolved independently in cartilaginous fishes.


Assuntos
Genes de Imunoglobulinas/genética , Switching de Imunoglobulina/genética , Isotipos de Imunoglobulinas/genética , RNA/genética , Tubarões/genética , Tubarões/imunologia , Animais , Sequência de Bases , Southern Blotting , Genes de Imunoglobulinas/imunologia , Switching de Imunoglobulina/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Isotipos de Imunoglobulinas/imunologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
PLoS One ; 7(4): e35158, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22514717

RESUMO

PURPOSE: microRNAs have emerged as key regulators of gene expression, and their altered expression has been associated with tumorigenesis and tumor progression. Thus, microRNAs have potential as both cancer biomarkers and/or potential novel therapeutic targets. Although accumulating evidence suggests the role of aberrant microRNA expression in endometrial carcinogenesis, there are still limited data available about the prognostic significance of microRNAs in endometrial cancer. The goal of this study is to investigate the prognostic value of selected key microRNAs in endometrial cancer by the analysis of archival formalin-fixed paraffin-embedded tissues. EXPERIMENTAL DESIGN: Total RNAs were extracted from 48 paired normal and endometrial tumor specimens using Trizol based approach. The expression of miR-26a, let-7g, miR-21, miR-181b, miR-200c, miR-192, miR-215, miR-200c, and miR-205 were quantified by real time qRT-PCR expression analysis. Targets of the differentially expressed miRNAs were quantified using immunohistochemistry. Statistical analysis was performed by GraphPad Prism 5.0. RESULTS: The expression levels of miR-200c (P<0.0001) and miR-205 (P<0.0001) were significantly increased in endometrial tumors compared to normal tissues. Kaplan-Meier survival analysis revealed that high levels of miR-205 expression were associated with poor patient overall survival (hazard ratio, 0.377; Logrank test, P = 0.028). Furthermore, decreased expression of a miR-205 target PTEN was detected in endometrial cancer tissues compared to normal tissues. CONCLUSION: miR-205 holds a unique potential as a prognostic biomarker in endometrial cancer.


Assuntos
Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , MicroRNAs/genética , Feminino , Humanos , Técnicas In Vitro , Prognóstico
10.
Clin Colorectal Cancer ; 10(4): 340-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21752725

RESUMO

BACKGROUND: We have previously shown that miR-215 suppressed the expression of key targets such as thymidylate synthase (TS), dihydrofolate reductase, and denticleless protein homolog (DTL) in colon cancer. miR-215 is a tumor suppressor candidate due to the upregulation of p53 and p21 by targeting DTL. However, high levels of miR-215 conferred chemoresistance due to cell cycle arrest and reduced cell proliferation by suppressing DTL. In this study, the clinical significance of miR-215 was further investigated as a potential prognostic biomarker in colon cancer patients. METHODS: Total RNAs were extracted from 34 paired normal and colon (stage II and III) tumor specimens using the Trizol-based approach. The levels of miR-215 and a closely related miR-192 were quantified using quantitative real-time polymerase chain reaction (qRT-PCR) expression analysis. The expression of DTL mRNA and protein were quantified by real time qRT-PCR and immunohistochemistry. RESULTS: The expression levels of miR-192 (P = .0008) and miR-215 (P < .0001) were significantly decreased in colon tumors compared with normal tissues. DTL was significantly over-expressed and was inversely correlated with miR-215, further suggesting an in vivo physiologic relevance of miR-215 mediated DTL suppression. Kaplan-Meier survival analysis by Cox regression revealed that high levels of miR-215 expression (hazard ratio, 3.516; 95% confidence interval, 1.007-12.28, P = .025) are closely associated with poor patient's overall survival. Furthermore, an elevated expression of a miR-215 target protein DTL was detected in colon cancer tissues whereas no expression was present in normal tissues. CONCLUSION: miR-215 has a unique potential as a prognostic biomarker in stage II and III colon cancer.


Assuntos
Adenocarcinoma/genética , Colo/metabolismo , Neoplasias do Colo/genética , MicroRNAs/genética , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/metabolismo , Neoplasias do Colo/mortalidade , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Nucleares/genética , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Taxa de Sobrevida , Tetra-Hidrofolato Desidrogenase/metabolismo , Timidilato Sintase/metabolismo , Análise Serial de Tecidos , Ubiquitina-Proteína Ligases/genética
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