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1.
Mar Pollut Bull ; 173(Pt A): 112896, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34601248

RESUMO

Profiles of 33 PFAS analytes and 12 essential and non-essential trace elements were measured in livers of stranded common dolphins (Delphinus delphis) from New Zealand. PFAS concentrations reported were largely comparable to those measured in other marine mammal species globally and composed mostly of long-chain compounds including perfluorooctanesulfonic acid (PFOS), perfluorododecanoic acid (PFDoDA), perfluorotridecanoic acid (PFTrDA) and perfluorooctanesulfonamide (FOSA). PFAS profiles did not vary significantly by location, body condition, or life history. Notably, significant positive correlations were observed within respective PFAS and trace elements. However, only negative correlations were evident between these two contaminant types, suggesting different exposure and metabolic pathways. Age-associated concentrations were found for PFTrDA and four trace elements, i.e. silver, mercury, cadmium, selenium, indicating differences in the bioaccumulation biomagnification mechanisms. Overall, our results contribute to global understanding of accumulation of PFAS by offering first insights of PFAS exposure in cetaceans living within South Pacific Australasian waters.


Assuntos
Ácidos Alcanossulfônicos , Golfinhos Comuns , Fluorocarbonos , Oligoelementos , Animais , Monitoramento Ambiental , Fluorocarbonos/análise , Nova Zelândia , Oligoelementos/análise
2.
Clin Transl Oncol ; 23(8): 1601-1610, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33566304

RESUMO

INTRODUCTION: The inflammatory microenvironment has emerged as one of the focuses of cancer research. Little is known about the immune environment in esophageal adenocarcinoma (EAC) and possible tumor-escape mechanisms to avoid immune cell attack. PATIENTS AND METHODS: We measured T cell inflammation (CD3, CD8) in the microenvironment using a standardized software-based evaluation algorithm considering different predefined tumor areas as well as expression of MHC class 1 and PD-L1 on 75 analyzable primarily resected and locally advanced (≥ pT2) EACs. We correlated these findings statistically with clinical data. RESULTS: Patients with high amounts of T cell infiltration in their tumor center showed a significant survival benefit of 41.4 months compared to 16.3 months in T cell poor tumors (p = 0.025), although CD3 fails to serve as an independent prognostic marker in multivariate analysis. For the invasion zone, a correlation between number of T-cells and overall survival was not detectable. Loss of MHC1 protein expression on tumor cells was seen in 32% and PD-L1 expression using the combined positive score (CPS) in 21.2%. Most likely due to small numbers of cases, both markers are not prognostically relevant, even though PD-L1 expression correlates with advanced tumor stages. DISCUSSION: Our analyses reveal an outstanding, though not statistically independent, prognostic relevance of T-cell-rich inflammation in our group of EACs, in particular driven by the tumor center. For the first time, we describe that the inner part of the invasion zone in EACs shows significantly fewer T-cells than other tumor segments and is prognostically irrelevant. We also demonstrate that the loss of antigen presenting ability via MHC1 downregulation by the carcinoma cells is a common escape mechanism in EACs. Future work will need to show whether tumors with MHC class 1 loss respond less well to immunotherapy.


Assuntos
Adenocarcinoma/imunologia , Neoplasias Esofágicas/imunologia , Linfócitos do Interstício Tumoral/citologia , Evasão Tumoral/imunologia , Microambiente Tumoral/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Antígeno B7-H1/análise , Antígeno B7-H1/metabolismo , Regulação para Baixo , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Antígenos HLA-A/análise , Antígenos HLA-A/metabolismo , Antígenos HLA-B/análise , Antígenos HLA-B/metabolismo , Humanos , Imunidade Celular , Inflamação/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/imunologia , Prognóstico , Fatores de Tempo
3.
Blood ; 136(24): 2786-2802, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33301031

RESUMO

T-cell prolymphocytic leukemia (T-PLL) is a poor-prognostic neoplasm. Differentiation stage and immune-effector functions of the underlying tumor cell are insufficiently characterized. Constitutive activation of the T-cell leukemia 1A (TCL1A) oncogene distinguishes the (pre)leukemic cell from regular postthymic T cells. We assessed activation-response patterns of the T-PLL lymphocyte and interrogated the modulatory impact by TCL1A. Immunophenotypic and gene expression profiles revealed a unique spectrum of memory-type differentiation of T-PLL with predominant central-memory stages and frequent noncanonical patterns. Virtually all T-PLL expressed a T-cell receptor (TCR) and/or CD28-coreceptor without overrepresentation of specific TCR clonotypes. The highly activated leukemic cells also revealed losses of negative-regulatory TCR coreceptors (eg, CTLA4). TCR stimulation of T-PLL cells evoked higher-than-normal cell-cycle transition and profiles of cytokine release that resembled those of normal memory T cells. More activated phenotypes and higher TCL1A correlated with inferior clinical outcomes. TCL1A was linked to the marked resistance of T-PLL to activation- and FAS-induced cell death. Enforced TCL1A enhanced phospho-activation of TCR kinases, second-messenger generation, and JAK/STAT or NFAT transcriptional responses. This reduced the input thresholds for IL-2 secretion in a sensitizer-like fashion. Mice of TCL1A-initiated protracted T-PLL development resembled such features. When equipped with epitope-defined TCRs or chimeric antigen receptors, these Lckpr-hTCL1Atg T cells gained a leukemogenic growth advantage in scenarios of receptor stimulation. Overall, we propose a model of T-PLL pathogenesis in which TCL1A enhances TCR signals and drives the accumulation of death-resistant memory-type cells that use amplified low-level stimulatory input, and whose loss of negative coregulators additionally maintains their activated state. Treatment rationales are provided by combined interception in TCR and survival signaling.


Assuntos
Memória Imunológica , Leucemia Prolinfocítica de Células T/imunologia , Proteínas Proto-Oncogênicas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Humanos , Leucemia Prolinfocítica de Células T/genética , Leucemia Prolinfocítica de Células T/patologia , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas/genética , Receptores de Antígenos de Linfócitos T/genética , Transdução de Sinais/genética , Linfócitos T/patologia
4.
Am J Transplant ; 17(2): 542-550, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27529836

RESUMO

Immunosuppressive strategies applied in renal transplantation traditionally focus on T cell inhibition. B cells were mainly examined in the context of antibody-mediated rejection, whereas the impact of antibody-independent B cell functions has only recently entered the field of transplantation. Similar to T cells, distinct B cell subsets can enhance or inhibit immune responses. In this study, we prospectively analyzed the evolution of B cell subsets in the peripheral blood of AB0-compatible (n = 27) and AB0-incompatible (n = 10) renal transplant recipients. Activated B cells were transiently decreased and plasmablasts were permanently decreased in patients without signs of rejection throughout the first year. In patients with histologically confirmed renal allograft rejection, activated B cells and plasmablasts were significantly elevated on day 365. Rituximab treatment in AB0-incompatible patients resulted in long-lasting B cell depletion and in a naïve phenotype of repopulating B cells 1 year following transplantation. Acute allograft rejection was correlated with an increase of activated B cells and plasmablasts and with a significant reduction of regulatory B cell subsets. Our study demonstrates the remarkable effects of standard immunosuppression on circulating B cell subsets. Furthermore, the B cell compartment was significantly altered in rejecting patients. A specific targeting of deleterious B cell subsets could be of clinical benefit in renal transplantation.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Transplantados , Adulto , Subpopulações de Linfócitos B/imunologia , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Humanos , Imunossupressores/uso terapêutico , Doadores Vivos , Masculino , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco , Transplante Homólogo
5.
Sci Rep ; 5: 8875, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25748167

RESUMO

Plasma glucose levels provide the cornerstone of diabetes evaluation. Unfortunately, glucose levels drop in vitro due to glycolysis. Guidelines provide suitable conditions which minimize glycolysis, such as immediate centrifugation or the use of ice/water slurry storage containers. For obvious practical reasons, most laboratories use blood collection tubes containing glycolysis inhibitors. We describe the effect of a variety of commonly used blood collection tubes on in vitro stability of glucose. Furthermore, we looked at the validity of the assumption that glycolytic activity is minimal when blood is kept in an ice/water slurry. Sodium fluoride alone does not reduce in vitro glycolysis in the first 120 minutes after phlebotomy. Addition of citrate almost completely prevented in vitro glycolysis, but showed a positive bias (0.2 mmol/l) compared to control. This is partly due to a small drop in glucose level in control blood, drawn according to the current guidelines. This drop occurs within 15 minutes, in which glycolysis has been described to be minimal and acceptable. NaF-EDTA-citrate based test tubes provide the best pre-analytical condition available. Furthermore, glucose levels are not stable in heparinized blood placed in an ice/water slurry. We strongly advise the use of NaF-EDTA-citrate based test tubes in diabetes research.


Assuntos
Artefatos , Glicemia/química , Coleta de Amostras Sanguíneas/métodos , Citratos/química , Gelo , Fluoreto de Sódio/química , Glicemia/análise , Feminino , Glicólise/efeitos dos fármacos , Humanos , Masculino
6.
Transl Psychiatry ; 4: e358, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24495969

RESUMO

To follow-up loci discovered by the International Genomics of Alzheimer's Disease Project, we attempted independent replication of 19 single nucleotide polymorphisms (SNPs) in a large Spanish sample (Fundació ACE data set; 1808 patients and 2564 controls). Our results corroborate association with four SNPs located in the genes INPP5D, MEF2C, ZCWPW1 and FERMT2, respectively. Of these, ZCWPW1 was the only SNP to withstand correction for multiple testing (P=0.000655). Furthermore, we identify TRIP4 (rs74615166) as a novel genome-wide significant locus for Alzheimer's disease risk (odds ratio=1.31; confidence interval 95% (1.19-1.44); P=9.74 × 10(-)(9)).


Assuntos
Doença de Alzheimer/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Fatores de Transcrição/genética , Seguimentos , Loci Gênicos/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Espanha
7.
Artigo em Alemão | MEDLINE | ID: mdl-22842893

RESUMO

What kind of health targets should be pursued concerning the health care of elderly people? What kind of activities should be implemented to ensure good health care with regard to future challenges? The Association for the Continuous Development of the National Health Target Process, health-targets.de, deals with these issues under the new national health target "Healthy Ageing". We develop concrete objectives and proposals for practical implementation in the areas of "outpatient and inpatient care", "nursing" and "rehabilitation in old age". health-targets.de supports a common health target process and initiates interventions in the field of health care for elderly people.


Assuntos
Envelhecimento/psicologia , Doença Crônica/enfermagem , Avaliação Geriátrica , Qualidade de Vida/psicologia , Ajustamento Social , Idoso , Idoso de 80 Anos ou mais , Doença Crônica/psicologia , Comportamento Cooperativo , Avaliação da Deficiência , Feminino , Controle de Acesso , Alemanha , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Humanos , Comunicação Interdisciplinar , Masculino , Admissão do Paciente , Equipe de Assistência ao Paciente
8.
Immunol Lett ; 145(1-2): 30-8, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-22698181

RESUMO

A subset of chemokine receptors, initially called "silent" on the basis of their apparent failure to activate conventional signalling events, has recently attracted growing interest due to their ability to internalize, degrade, or transport ligands and thus modify gradients and create functional chemokine patterns in tissues. These receptors recognize distinct and complementary sets of ligands with high affinity, are strategically expressed in different cellular contexts, and lack structural determinants supporting Gα(i) activation, a key signalling event in cell migration. This is in keeping with the hypothesis that they have evolved to fulfil fundamentally different functions to the classical signalling chemokine receptors. Based on these considerations, these receptors (D6, Duffy antigen receptor for chemokines (DARC), CCX-CKR1 and CXCR7) are now collectively considered as an emerging class of 'atypical' chemokine receptors. In this article, we review the biochemistry and biology of this emerging chemokine receptor subfamily.


Assuntos
Sistema do Grupo Sanguíneo Duffy/imunologia , Receptores CCR/imunologia , Receptores CXCR/imunologia , Receptores de Superfície Celular/imunologia , Receptores de Quimiocinas/imunologia , Animais , Evolução Biológica , Humanos , Imunomodulação , Transdução de Sinais , Transcitose
10.
Exp Clin Endocrinol Diabetes ; 114(5): 222-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16804795

RESUMO

AIM: The factors influencing success of treating Graves' disease with radioiodine ( (131)I) are discussed controversially. This study analyses prospectively the influence of discontinuing antithyroid drugs (ATD) immediately prior to treatment with radioiodine on the therapeutic outcome. METHODS: We studied 141 patients with Graves' disease. In 73 of them (group A) treatment was performed under medication with ATD, in 68 patients (group B) ATD were discontinued for 3 - 7 days starting at the time of therapy. We performed a statistical analysis of the influence of ATD and other factors potentially influencing treatment results. RESULTS: In group A 49/73 patients were treated successfully (67 %) vs. 58/68 (85 %) in group B (p < 0.01). Characteristic changes in the kinetics of radioiodine were observed: after discontinuing ATD specific uptake was higher (2.0 %/ml in group A vs. 2.6 %/ml in group B, p = 0.004), and the effective half life was longer (5.1 +/- 1.3 d in group A vs. 5.5 +/- 1.1 d in group B, p = 0.076) resulting in a significantly higher radiation dose in group B (200 +/- 61 Gy in group A vs. 236 +/- 72 Gy in group B, p = 0.002). CONCLUSION: We conclude that short-term interruption of ATD improves the success rate of treating Graves' disease with radioiodine significantly.


Assuntos
Antitireóideos/uso terapêutico , Doença de Graves/tratamento farmacológico , Doença de Graves/radioterapia , Radioisótopos do Iodo/uso terapêutico , Suspensão de Tratamento , Idoso , Feminino , Humanos , Radioisótopos do Iodo/farmacocinética , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
11.
Rofo ; 177(11): 1489-90, 2005 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-16302128
12.
Rofo ; 177(10): 1380-6, 2005 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-16170707

RESUMO

PURPOSE: To assess the benefit and the effect of intraarterial lipiodol application on histological analysis of patients suspected of having HCC. To determine whether lipiodol marking leads to a better biopsy result and how lipiodol or a transarterial chemoembolization influences the histological diagnosis. MATERIALS AND METHODS: Two groups of patients were examined. Group A included 14 patients highly suspected of having an HCC which had previously been unsuccessfully biopsied. A transarterial embolization with lipiodol was performed in these patients to mark intrahepatic tumors which could not otherwise be defined in unenhanced CT. A biopsy was then repeated. Group B included 22 patients undergoing therapy using transarterial chemoembolization (TACE). A biopsy was performed to support the diagnosis of a multifocal HCC before changing the therapy. RESULTS: The transversal diameters of the biopsied tumors were similar in both groups (A: 22 mm; B: 21 mm). The length of percutaneous access was 71 mm in Group A and 88 mm in Group B. In eleven of 14 patients of Group A we confirmed the diagnosis of an HCC. Thirty-six procedures were necessary for this confirmation. In Group B we confirmed the diagnosis in 17 of 22 patients. In addition, we found typical histological modification due to hepatic cirrhosis and virus hepatitis. Lipiodol had no negative influence on the histological diagnosis. CONCLUSION: Applying lipiodol for marking and delineating HCC-suspicious liver tumors in cases of formerly negative histology seems to enhance the success of biopsy, confirming the diagnosis of an HCC.


Assuntos
Biópsia/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Meios de Contraste , Óleo Iodado , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Rofo ; 177(5): 646-54, 2005 May.
Artigo em Alemão | MEDLINE | ID: mdl-15871079

RESUMO

PURPOSE: Little is known about the dispersion of a defined contrast bolus during its passage through the heart and pulmonary vasculature. The purpose of this study was to analyze factors influencing a defined contrast bolus for ce-MRA of thoracic vessels. MATERIALS AND METHODS: For analysis of bolus geometry, an ECG-gated saturation-recovery Turbo-Flash sequence with a TI of 20 msec was used. It was acquired axially at the level of the pulmonary trunc, so that with one data acquisition a curve analysis was possible in the ascending and descending aorta, and in the pulmonary trunc. Twenty-nine patients received 3 ml of Gd-DTPA diluted with saline to a total of 20 ml. Contrast injection was done using a MR compatible power injector with injection rates varying between 1, 2 and 4 ml/sec. Each injection was followed by a saline flush of 20 ml with the same injection rate and mode. Cardiac function was assessed by cine imaging, and phase contrast measurements. After normalization to baseline signal intensity (SI), bolus curves were fitted using a gamma-variate fit and peak signal intensity (peak SI), time-to-peak (TP), upslope, mean transit time (MTT) and dispersion of the contrast bolus were calculated. Furthermore, T (1) and [Gd] in the experimental setting were calculated as follows: T (1) = T (1 o)/ ln [SI/SI (0)], and [Gd] (exp) = [1/T (1) - 1/T (1 o)]/ R (1.) They were then extrapolated [Gd] to clinical conditions by [Gd] (clin) = [Gd] (exp) . 10/1.5, and minimal blood T (1) by T (1)(clin) = 1 / [1/T (1 o) + R (1) [Gd] (clin)]. RESULTS: With increasing injection rate, there was a significant decrease (p < 0.001) of MTT in all target vessels. However, this decrease was not linear: a 4-fold increase in injection rate lead to a 2-fold decrease in MTT e. g. in the ascending aorta. MTT was significantly shorter in the pulmonary trunc compared with that in the ascending and descending aorta (p < 0.001), regardless of injection rate (p < 0.001). Vice versa, dispersion of the contrast bolus was significantly lower in the pulmonary trunc, and increased with higher injection rates. There was no clinically relevant difference in minimal blood T (1) between the different target vessels, for clinical conditions extrapolated values ranged between 20 und 79 msec. Heart function parameters only had a minor influence of bolus curve parameters. CONCLUSION: Analysis of bolus geometry enables determination of transit times of a defined contrast bolus through a defined target vessel in the thoracic cavity. Bolus geometry is mainly determined by injection parameters, cardiac function is of minor importance. Dispersion of contrast bolus and MTT increase from the pulmonary trunc to the ascending aorta. The knowledge of these facts may help optimizing of injection parameters and the total amount of contrast agent for contrast-enhanced MRA of thoracic vessels.


Assuntos
Meios de Contraste , Gadolínio DTPA , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Tórax/irrigação sanguínea , Tórax/patologia , Adulto , Idoso , Cardiomiopatias/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Rofo ; 177(5): 655-9, 2005 May.
Artigo em Alemão | MEDLINE | ID: mdl-15871080

RESUMO

PURPOSE: : Comparison of emphysema index derived of thin section MD-CT of the entire lung volume and HRCT, simulated by calculation of every twentieth image of the whole data-set. MATERIALS AND METHODS: Pulmonary emphysema was quantified by semiautomatic, segmentation of lung borders and assessment of lung volume and emphysema volume within these borders. The emphysema index (pixel index) was calculated. Statistical analysis was done by the sign-test and Bland-Altman-analysis. RESULTS: Median lung volume, emphysema volume and emphysema index are significantly higher in simulated HRCT. Median lung volume (emphysema volume) calculated by HRCT is 5118 ml (407 ml) and 5040 ml (367 ml) calculated by the entire MD-CT data-set, representing differences of 1 and 8 % related to the median lung and emphysema volumes. Emphysema index is 0.09 (HRCT) and 0.08 (MD-CT). CONCLUSION: HRCT overrates emphysema index compared to thin section MD-CT of the entire lung volume.


Assuntos
Anatomia Transversal/métodos , Enfisema/classificação , Enfisema/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Imageamento Tridimensional/métodos , Armazenamento e Recuperação da Informação/métodos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Rofo ; 177(5): 681-90, 2005 May.
Artigo em Alemão | MEDLINE | ID: mdl-15871083

RESUMO

PURPOSE: Analysis of the course of disease in patients with histologically proven HCC before and after orthotopic liver transplantation (LTx) who received transarterial chemoembolization (TACE). MATERIAL AND METHODS: Thirty-five of a total collective of 363 patients with histologically proven HCC underwent LTx. Before LTx, all patients were treated with sequential TACE. According to treatment pattern, TACE should be performed every 6 weeks, using a suspension consisting of max. 10 mg Mitomycin C as well as 10 - 30 ml iodized oil (Lipiodol). Patients were classified according to the Milano criteria. Criteria were called exceeded if the tumor size was > 5 cm and/or > 3 tumors larger than 3 cm were found. Therapy success and liver function were examined by means of spiral CT and laboratory controls. Investigation parameters included the number of tumor knots as well as the maximum tumor size. Additionally, the Lipiodol accumulation, the patency of the portal vein and the occurrence of complications were checked. RESULTS: Altogether, 184 TACE procedures were accomplished (5.3 +/- 3.3, range 1 - 14). The waiting period up to the transplantation amounted to 366 +/- 255 days (range 44 - 1137). The average number of tumor knots for each patient was 3.1 +/- 2.2 before and 2.9 +/- 2.2 after TACE (p = 0.887). The average tumor size was 4.2 +/- 2.5 before and 2.8 +/- 1.4 after TACE. The Milano criteria to LTx crossed 17/35 patients. Patients with exceeded Milan criteria showed a highly significant size reduction of the tumor after TACE (p = 0.001); in 9/17 cases the transplantation criteria were secondarily fulfilled through downstaging. A successful LTx was accomplished in 35/35 cases. Follow up after LTx was 769 +/- 509 days. The tumor recurrence in patients with exceeded vs. fulfilled transplantation criteria was 11.1 % vs. 11.8 % (p = 0.99). The recurrence free survival was 93.3 %, 82.5 % and 82.5 % at 1, 3 and 5 years, respectively. There were no relevant differences between patients with exceeded vs. fulfilled transplantation criteria (p = 0.99). CONCLUSION: The sequential TACE is an effective method for the therapy of the HCC before LTx in selected patients. A relevant downsizing could be achieved by TACE in patients with advanced HCC. Patients with larger tumors showed a significantly stronger size reduction after TACE. The recurrence rate and the survival rate for patients with advanced or small tumors do not differ.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Transplante de Fígado/métodos , Cuidados Pré-Operatórios/métodos , Medição de Risco/métodos , Adulto , Idoso , Antineoplásicos/administração & dosagem , Feminino , Humanos , Óleo Iodado/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Prognóstico , Radiografia , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
16.
Rofo ; 177(5): 703-13, 2005 May.
Artigo em Alemão | MEDLINE | ID: mdl-15871086

RESUMO

PURPOSE: Investigation and statistical evaluation of "Self-Organizing Maps," a special type of neural networks in the field of artificial intelligence, classifying contrast enhancing lesions in dynamic MR-mammography. MATERIAL AND METHODS: 176 investigations with proven histology after core biopsy or operation were randomly divided into two groups. Several Self-Organizing Maps were trained by investigations of the first group to detect and classify contrast enhancing lesions in dynamic MR-mammography. Each single pixel's signal/time curve of all patients within the second group was analyzed by the Self-Organizing Maps. The likelihood of malignancy was visualized by color overlays on the MR-images. At last assessment of contrast-enhancing lesions by each different network was rated visually and evaluated statistically. RESULTS: A well balanced neural network achieved a sensitivity of 90.5 % and a specificity of 72.2 % in predicting malignancy of 88 enhancing lesions. Detailed analysis of false-positive results revealed that every second fibroadenoma showed a "typical malignant" signal/time curve without any chance to differentiate between fibroadenomas and malignant tissue regarding contrast enhancement alone; but this special group of lesions was represented by a well-defined area of the Self-Organizing Map. DISCUSSION: Self-Organizing Maps are capable of classifying a dynamic signal/time curve as "typical benign" or "typical malignant." Therefore, they can be used as second opinion. In view of the now known localization of fibroadenomas enhancing like malignant tumors at the Self-Organizing Map, these lesions could be passed to further analysis by additional post-processing elements (e.g., based on T2-weighted series or morphology analysis) in the future.


Assuntos
Algoritmos , Neoplasias da Mama/patologia , Meios de Contraste , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Inteligência Artificial , Neoplasias da Mama/classificação , Feminino , Humanos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Armazenamento e Recuperação da Informação/métodos , Mamografia/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
17.
Rofo ; 177(4): 516-23, 2005 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-15838756

RESUMO

PURPOSE: Visual assessment of the ventilation using HRCT and (3)He-MRI in patients after single lung transplantation (SLTX). Analysis of specific ventilation defects found with (3)He-MRI and morphological changes found with HRCT. MATERIALS AND METHODS: We evaluated 8male patients (54 +/- 6 years) suffering from emphysema and six patients (3males and 3 females, 58 +/- 9.5 years) suffering from idiopathic pulmonary fibrosis (IPF) after SLTX. The morphological changes at HRCT were classified and localized. In (3)He-MRI (2D FLASH), 10 to 14 slices (slice thickness 10 mm, gap 5 mm) were acquired in coronal orientation to cover the whole lung. Ventilation defects were localized and characterized. The visually estimated ventilation was recorded on a 5-point scoring system. A double threshold technique was applied to volumetric quantification in (3)He-MRI to serve as internal reference. RESULTS: We found no correlation between morphological changes in HRCT and ventilation defects in (3)He-MRI. The visual assessment of ventilation in (3)He-MRI was sufficient in patients with emphysema, but this was not confirmed in patients with IPF. The visual assessment in HRCT did not correlate with the volumetric evaluation in both conditions. CONCLUSION: The various ventilation defects were not linked to specific morphological changes. For the visually assessed ventilation in patients with emphysema, (3)He-MRI is superior to HRCT.


Assuntos
Enfisema/diagnóstico , Enfisema/cirurgia , Interpretação de Imagem Assistida por Computador/métodos , Transplante de Pulmão/diagnóstico por imagem , Transplante de Pulmão/patologia , Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/cirurgia , Feminino , Hélio , Humanos , Isótopos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Intensificação de Imagem Radiográfica/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
18.
Rofo ; 177(1): 24-34, 2005 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-15657817

RESUMO

This article describes the classification of endoleaks after endovascular treatment of abdominal aortic aneurysms, thereby summarizing the most important problems of this endovascular technique. The correct classification of endoleaks is a prerequisite for interdisciplinary discussion. It is indispensable for professional reporting of the pathological findings and for the decision making as to the adequate treatment of endoleaks. Irrespective of the types of stent graft and property of the material, five endoleak types are defined in the literature: leakage at the anchor sites (type I); leakage due to collateral arteries (type II); defective stent grafts (type III); leakage due to porosity of the graft material (type IV); and endotension (type V). The causes of endoleaks are discussed and treatment options are reviewed for the diverse pathologic findings.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Complicações Pós-Operatórias , Stents , Ligas , Angiografia , Cateterismo , Circulação Colateral , Embolização Terapêutica , Humanos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Fatores de Risco , Stents/efeitos adversos , Fatores de Tempo
19.
Eur Radiol ; 15(2): 312-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15565315

RESUMO

The purpose of this study was to determine right ventricular (RV) function from 16-detector-row CT by using two different software tools in comparison with MRI. Nineteen patients underwent cardiac CT. (1) With semiautomated contour detection software end-diastolic and end-systolic RV volumes were determined from short-axis CT reformations (MPR) created at every 10% of the RR-interval. (2) End-systolic and end-diastolic axial images were transformed to 3D to determine the volumes by using a threshold-supported reconstruction algorithm. Steady-state free-precession cine-MRI of the heart was done in short-axis orientation. RV function could not be analyzed in one patient because of sternal wire artifacts in MRI. Mean end-diastolic (155.4+/-54.6 ml) and end-systolic (79.1+/-37.0 ml) RV volumes determined with MPR correlated well with MRI [151.9+/-53.7 ml (r=0.98) and 75.0+/-36.0 ml (r=0.96), respectively (P<0.001)]. RV stroke volume (76.2+/-20.2 ml for MPR-CT, 76.9+/-20.7 ml for MRI, r=0.93) showed a good correlation and RV ejection fraction (50.8+/-8.4% for MPR-CT, 51.9+/-7.4% for MRI, r=0.74) only a moderate one. Threshold supported 3D reconstructions revealed insufficient correlations with MRI (r=0.31-0.59). MPR-based semiautomated analysis of cardiac 16 detector-row CT allows for RV functional analysis. The results correlate well with MRI findings. Threshold value-supported 3D reconstructions did not show satisfying results because of inhomogeneities of RV contrast enhancement.


Assuntos
Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Função Ventricular Direita/fisiologia , Idoso , Meios de Contraste , Feminino , Frequência Cardíaca/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas
20.
Rofo ; 176(12): 1750-8, 2004 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-15573285

RESUMO

PURPOSE: To compare the results of the preoperative workup consisting of endoscopic retrograde cholangiography (ERC), magnetic resonance cholangiography (MRC), and percutaneous resonance cholangiography (PTC) with the tumor extent of the surgical specimen in patients with hilar cholangiocarcinoma (hilCC). MATERIALS AND METHODS: Between 9/1997 and 12/2002, 59 patients with hilCC tumor underwent surgical resection. Preoperative ERC, MRC, and PTC were analyzed, blinded for the identity of the patient, and compared with the surgical specimen. For this retrospective analysis, 55 of the initial 59 ERCs, 39 of the initial 40 MRCs and 32 of the initial 38 PTCs were available. Most of the ERCs and MRCs had been performed at referring institutions by various investigators. In 20 patients, all three imaging modalities were available for direct comparison. RESULTS: The mean scores of the visualization of the bile ducts and tumor differ considerably for ERC, MRC and PTC, with PTC visualizing the bile ducts better than ERC (p < 0.001) and MRC (p = 0.019). The tumor classification according to Bismuth and Corlette was correctly predicted by ERC in 29 %, by MRC in 36 % and by PTC in 53 %. The tumor extent was overestimated in 40 % (ERC), 41 % (MRC) and 31 % (PTC) and underestimated in less than 10 % for all modalities. Twenty patients, who underwent all three imaging modalities, were included in an additional analysis for a direct comparison of ERC, MRC and PTC. PTC provided correct or acceptable information on tumor extent in 19 of 20 patients, MRC in 15 of 20 patients, and ERC in only 11 of 20 patients. The statistical analysis revealed a significant superiority of PTC to ERC (McNemar test: p < 0.01) but not to MRC (p = 0.22). DISCUSSION: The management of patients with hilar cholangiocarcinoma requires a high degree of expertise in diagnostic imaging techniques. Cholangiography should not only define the location but also visualize the uppermost extent of the tumor to determine resectability. In contrast to most reports in the literature, ERC and MRC were found to be of limited reliability regarding the assessment of the tumor extent. ERC may be more and more reserved for patients considered for nonsurgical intervention or palliation. PTC proved to be the most reliable approach. MRC represents a noninvasive diagnostic tool for the evaluation of malignant perihilar biliary obstructions, but should be performed at highest quality using state-of-the-art MRI techniques. The most common mistake of each diagnostic modality was an overestimated tumor extent, which may exclude patients from potentially curative surgery.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/diagnóstico , Colangiografia/métodos , Colangiopancreatografia Retrógrada Endoscópica , Colangiopancreatografia por Ressonância Magnética/métodos , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
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