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1.
Cancer ; 120(14): 2199-206, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24752999

RESUMO

BACKGROUND: The authors investigated whether cancer patients who have comorbid mental health disorders (MD) are at greater risk of early retirement compared with those who do not have MD. METHODS: Individuals ages 18 to 55 years from a consecutive sample of patients who were admitted for inpatient oncologic treatment were interviewed using structured clinical interviews to ascertain MD. The patients were followed for 15 months, and the date of early retirement was documented. Rates of early retirement per 100 person-years (py) in patients with and without MD were compared using multivariate Poisson regression models. RESULTS: At baseline, 491 patients were interviewed, and 150 of those patients (30.6%) were diagnosed with MD. Forty-one patients began full early retirement during follow-up. In patients with MD, the incidence of early retirement was 9.3 per 100 py compared with 6.1 per 100 py in mentally healthy patients. The crude rate ratio (RR) was 1.5 (95% confidence interval [CI], 0.8-2.8). The effect of MD on early retirement was modified in part by income: in patients with low income, the adjusted RR was 11.7, whereas no effect was observed in higher income groups. Patients with depression were at greater risk of retirement when they had higher income (RR, 3.4; P = .05). The effects of anxiety (RR, 2.4; P = .05), adjustment disorders (RR, 1.7; P = .21), and alcohol dependence (RR, 1.8; P = .40) on early retirement were equal across income groups. CONCLUSIONS: Mental health conditions are risk factors for early retirement in cancer patients, although this effect differs according to the type of disorder and the patient's income level.


Assuntos
Transtornos Mentais/epidemiologia , Neoplasias/epidemiologia , Aposentadoria/estatística & dados numéricos , Adulto , Alcoolismo/epidemiologia , Ansiedade/epidemiologia , Comorbidade , Depressão/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Razão de Chances , Distribuição de Poisson , Estudos Prospectivos
2.
Nat Commun ; 15(1): 3798, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714689

RESUMO

Transparent roofs and walls offer a compelling solution for harnessing natural light. However, traditional glass roofs and walls face challenges such as glare, privacy concerns, and overheating issues. In this study, we present a polymer-based micro-photonic multi-functional metamaterial. The metamaterial diffuses 73% of incident sunlight, creating a more comfortable and private indoor environment. The visible spectral transmittance of the metamaterial (95%) surpasses that of traditional glass (91%). Furthermore, the metamaterial is estimated to enhance photosynthesis efficiency by ~9% compared to glass roofs. With a high emissivity (~0.98) close to that of a mid-infrared black body, the metamaterial is estimated to have a cooling capacity of ~97 W/m2 at ambient temperature. The metamaterial was about 6 °C cooler than the ambient temperature in humid Karlsruhe. The metamaterial exhibits superhydrophobic performance with a contact angle of 152°, significantly higher than that of glass (26°), thus potentially having excellent self-cleaning properties.

3.
BMC Cancer ; 12: 578, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23217093

RESUMO

BACKGROUND: There is a lack of psychotherapeutic trials of treatments of comorbid depression in cancer patients. Our study determines the efficacy of a manualized short-term psychodynamic psychotherapy and predictors of outcome by personality and quality of the therapeutic relationship. METHODS/DESIGN: Eligible breast cancer patients with comorbid depression are assigned to short-term psychodynamic psychotherapy (up to 20 + 5 sessions) or to treatment as usual (augmented by recommendation for counseling center and physician information). We plan to recruit a total of 180 patients (90 per arm) in two centers. Assessments are conducted pretreatment, after 6 (treatment termination) and 12 months (follow-up). The primary outcome measures are reduction of the depression score in the Hospital Anxiety and Depression Scale and remission of depression as assessed by means of the Structured Clinical Interview for DSM IV Disorders by independent, blinded assessors at treatment termination. Secondary outcomes refer to quality of life. DISCUSSION: We investigate the efficacy of short-term psychodynamic psychotherapy in acute care and we aim to identify predictors for acceptance and success of treatment. TRIAL REGISTRATION: ISRCTN96793588.


Assuntos
Neoplasias da Mama/psicologia , Neoplasias da Mama/terapia , Depressão/etiologia , Depressão/terapia , Psicoterapia Breve/métodos , Adolescente , Adulto , Idoso , Comorbidade , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Adulto Jovem
4.
Breast Care (Basel) ; 17(5): 508-513, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36684406

RESUMO

Introduction: Noninterventional study (NIS) on application and effectiveness of primary G-CSF prophylaxis with lipegfilgrastim in primary breast cancer patients undergoing dose-dense (dd) or intense-dose-dense (idd) chemotherapy (CTx) regimen in daily clinical practice. Methods: Prospective, multicenter, single-arm, NIS in 41 private practices and 27 hospitals in Germany. Results: Data analysis of 282 patients with a mean age of 49 years (93.6% of patients <65 years) was performed. Hormone receptor status was triple negative in 29.8% of patients, and 81.9% of patients were HER2 negative. A total of 73.8% of patients received "EC dd → taxane CTx." Patients received lipegfilgrastim prophylaxis in 97.5% of 1,121 documented dd/idd cycles. Overall, the study registered 275 events of SN (CTCAE grade 3 or 4) and 9 events of FN. During the first dd cycle, SN occurred in 33.3% and FN in 1.1% of patients. CTx delay or dose reduction due to neutropenia was required in 2.5% of patients during the 4 dd cycles with lipegfilgrastim support. Overall, 314 adverse events (AEs) were reported from 107 patients and 27 serious AEs from 21 patients. None of the SAEs was "fatal," and CTCAE grade was mostly (89.6%) assessed as "1" or "2." According to the treating physicians, 99.3% of all patients benefitted from lipegfilgrastim prophylaxis, and tolerability was mostly rated "very good" or "good." Conclusion: These results suggest that primary lipegfilgrastim prophylaxis is effective and safe in clinical routine and is beneficial in primary breast cancer patients undergoing dd/idd-ETC CTx.

5.
Gynecol Oncol ; 116(1): 82-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19836828

RESUMO

OBJECTIVE: The aim of this study was to evaluate patients' acceptance and the reliability and validity of a recently developed instrument to assess quality of life among cervical cancer patients, the European Organization for Research and Treatment of Cancer Cervical Cancer Module (EORTC QLQ-CX24), in surgically treated patients after primary surgery. METHODS: The EORTC QLQ-CX24 was administered to 134 cervical cancer patients who had undergone pelvic surgery. Additional questionnaires completed were the EORTC QLQ-C30, and the Hospital Anxiety and Depression Scale. Sociodemographic and medical data were recorded. RESULTS: Missing values occurred in 4.5% of all non-optional items. Internal consistencies (Cronbach's alpha coefficients) for the three multi-item scales ranged from 0.70 to 0.87 (Symptom Experience 0.70, Body Image 0.87, Sexual/Vaginal Functioning 0.76), whereas scaling errors occurred in 6.8%, 0.0%, and 6.3% of the cases. In all domains, the entire range of the scale was used by patients. The scales were able to discriminate between different subgroups of patients. CONCLUSION: These psychometric analyses confirm that the EORTC QLQ-CX24 is a useful tool for the assessment of quality of life in cervical cancer patients after surgery.


Assuntos
Psicometria/métodos , Neoplasias do Colo do Útero/psicologia , Neoplasias do Colo do Útero/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Satisfação do Paciente , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
6.
J Cell Biochem ; 106(4): 729-37, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19173302

RESUMO

Hyperplasia and hypertrophy of fat cells can be found in obesity and increased adiposity is associated with endothelial dysfunction as an early event of atherosclerosis. However, it is unclear whether human adipocytes directly influence endothelial protein secretion. To study the crosstalk between fat and endothelial cells, human umbilical venous endothelial cells (HUVECs) were cultured in infranatants (Adipo) of primary differentiated human adipocytes. Interestingly, significantly increased secretion of 23 cytokines and chemokines from HUVECs was detected in four independent experiments after Adipo stimulation by protein array analysis detecting a total of 174 different proteins. Among those, time-dependent Adipo-induced upregulation of cytokine secretion in HUVECs was confirmed by ELISA for interleukin (IL)-8, monokine induced by gamma interferon, macrophage inflammatory protein (MIP)-1beta, MIP-3alpha, monocyte chemoattractant protein-1, and IL-6. Factors besides adiponectin, leptin, resistin, and tumor necrosis factor alpha appear to mediate these stimulatory effects. Our findings suggest that endothelial cell secretion is significantly influenced towards a proinflammatory pattern by adipocyte-secreted factors.


Assuntos
Adipócitos/metabolismo , Citocinas/metabolismo , Células Endoteliais/metabolismo , Comunicação Parácrina/imunologia , Adipócitos/imunologia , Células Cultivadas , Células Endoteliais/imunologia , Endotélio Vascular/citologia , Humanos , Mediadores da Inflamação , Proteínas/análise , Proteínas/metabolismo , Proteômica , Regulação para Cima
7.
J Bacteriol ; 190(5): 1546-53, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18156273

RESUMO

Streptomyces davawensis synthesizes the antibiotic roseoflavin, one of the few known natural riboflavin analogs, and is roseoflavin resistant. It is thought that the endogenous flavokinase (EC 2.7.1.26)/flavin adenine dinucleotide (FAD) synthetase (EC 2.7.7.2) activities of roseoflavin-sensitive organisms are responsible for the antibiotic effect of roseoflavin, producing the inactive cofactors roseoflavin-5'-monophosphate (RoFMN) and roseoflavin adenine dinucleotide (RoFAD) from roseoflavin. To confirm this, the FAD-dependent Sus scrofa D-amino acid oxidase (EC 1.4.3.3) was tested with RoFAD as a cofactor and found to be inactive. It was hypothesized that a flavokinase/FAD synthetase (RibC) highly specific for riboflavin may be present in S. davawensis, which would not allow the formation of toxic RoFMN/RoFAD. The gene ribC from S. davawensis was cloned. RibC from S. davawensis was overproduced in Escherichia coli and purified. Analysis of the flavokinase activity of RibC revealed that the S. davawensis enzyme is not riboflavin specific (roseoflavin, kcat/Km = 1.7 10(-2) microM(-1) s(-1); riboflavin, kcat/Km = 7.5 10(-3) microM(-1) s(-1)). Similar results were obtained for RibC from the roseoflavin-sensitive bacterium Bacillus subtilis (roseoflavin, kcat/Km = 1.3 10(-2) microM(-1) s(-1); riboflavin, kcat/Km = 1.3 10(-2) microM(-1) s(-1)). Both RibC enzymes synthesized RoFAD and RoFMN. The functional expression of S. davawensis ribC did not confer roseoflavin resistance to a ribC-defective B. subtilis strain.


Assuntos
Proteínas de Bactérias/metabolismo , Flavinas/metabolismo , Nucleotidiltransferases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Streptomyces/metabolismo , Antibacterianos/farmacologia , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Cromatografia Líquida de Alta Pressão , Farmacorresistência Bacteriana/genética , Mononucleotídeo de Flavina/química , Mononucleotídeo de Flavina/metabolismo , Flavina-Adenina Dinucleotídeo/análogos & derivados , Flavina-Adenina Dinucleotídeo/química , Flavina-Adenina Dinucleotídeo/metabolismo , Flavina-Adenina Dinucleotídeo/farmacologia , Flavinas/química , Teste de Complementação Genética , Cinética , Modelos Genéticos , Estrutura Molecular , Nucleotidiltransferases/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Riboflavina/análogos & derivados , Riboflavina/farmacologia , Streptomyces/efeitos dos fármacos , Streptomyces/genética
8.
FEBS Lett ; 581(2): 279-83, 2007 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-17214985

RESUMO

The GcpE enzyme converts 2-C-methyl-D-erythritol-2,4-cyclodiphosphate (MEcPP) into (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) in the penultimate step of the DOXP pathway for isoprene biosynthesis. Purification of the enzyme under exclusion of air leads to a preparation that contains solely [4Fe-4S] clusters. Kinetic studies showed that in the presence of the artificial reductant dithionite and MEcPP a new transient iron-sulfur-based signal is detected in electron paramagnetic resonance (EPR) spectroscopy. Similarity of this EPR signal to that detected in ferredoxin:thioredoxin reductase indicates that during the reaction an intermediate is directly bound to the active-site cluster.


Assuntos
Enzimas/química , Eritritol/análogos & derivados , Proteínas Ferro-Enxofre/química , Thermus thermophilus/enzimologia , Sítios de Ligação , Espectroscopia de Ressonância de Spin Eletrônica , Enzimas/isolamento & purificação , Eritritol/metabolismo , Ferro/análise , Proteínas Ferro-Enxofre/isolamento & purificação , Organofosfatos/metabolismo , Pentosefosfatos/metabolismo , Enxofre/análise
9.
Nucleic Acids Res ; 30(24): e141, 2002 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-12490732

RESUMO

Trans-splicing ribozymes are RNA-based catalysts capable of splicing RNA sequences from one transcript specifically into a separate target transcript. In doing so, a chimeric mRNA can be produced, and new gene activities triggered in living cells dependent on the presence of the target mRNA. Based on this ability of trans-splicing ribozymes to deliver new gene activities, a simple and versatile plating assay was developed in Saccharomyces cerevisiae for assessing and optimizing constructs in vivo. Trans-splicing ribozymes were used to splice sequences encoding a GAL4-derived transcription activator into a target transcript from a prevalent viral pathogen. The transcription activator translated from this new mRNA in turn triggered the expression of genes under the regulatory control of GAL4 upstream-activating sequences. Two of the activated genes complemented metabolic deficiencies in the host strain, and allowed growth on selective media. A simple genetic assay based on phenotypic conversion from auxotrophy to prototrophy was established to select efficient and specific trans-splicing ribozymes from a ribozyme library. This simple assay may prove valuable for selecting optimal target sites for therapeutic agents such as ribozymes, antisense RNA and antisense oligodeoxyribonucleotides, and for optimizing the design of the therapeutic agents themselves, in higher eukaryotes.


Assuntos
RNA Catalítico/metabolismo , Saccharomyces cerevisiae/genética , Divisão Celular/genética , Proteínas de Ligação a DNA , Teste de Complementação Genética , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Mutação , Plasmídeos/genética , RNA Catalítico/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transformação Genética
10.
FEBS Lett ; 579(28): 6433-8, 2005 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-16289098

RESUMO

In the malaria parasite Plasmodium falciparum isoprenoid precursors are synthesised inside a plastid-like organelle (apicoplast) by the mevalonate independent 1-deoxy-d-xylulose-5-phosphate (DOXP) pathway. The last reaction step of the DOXP pathway is catalysed by the LytB enzyme which contains a [4Fe-4S] cluster. In this study, LytB of P. falciparum was shown to be catalytically active in the presence of an NADPH dependent electron transfer system comprising ferredoxin and ferredoxin-NADP(+) reductase. LytB and ferredoxin were found to form a stable protein complex. These data suggest that the ferredoxin/ferredoxin-NADP(+) reductase redox system serves as the physiological electron donor for LytB in the apicoplast of P. falciparum.


Assuntos
Ferredoxina-NADP Redutase/metabolismo , Ferredoxinas/metabolismo , Plasmodium falciparum/enzimologia , Proteínas de Protozoários/metabolismo , Terpenos/metabolismo , Animais , Catálise , Transporte de Elétrons , NADP/metabolismo , Oxirredução , Paraquat/química , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética
11.
Biorheology ; 39(3-4): 467-74, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12122268

RESUMO

Steady flow of a blood mimicking fluid in a physiologically realistic model of the human carotid bifurcation was studied using both magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) modelling techniques. Quantitative comparisons of the 3D velocity field in the bifurcation phantom were made between phase contrast MRI measurements and CFD predictions. The geometry for the CFD model was reconstructed from T(1) weighted MR imaging of the test phantom. It was found that the predicted velocity fields were in fair agreement with MR measured velocities. In both the internal and external carotid arteries, the agreement between CFD predictions and MRI measurements was better along the inner-outer wall axis with a correlation factor C>0.897 (average 0.939) where the velocity profiles were skewed, than along the anterior-posterior axis (average correlation factor 0.876) where the velocity profiles were in M-shape.


Assuntos
Artérias Carótidas/fisiologia , Modelos Anatômicos , Modelos Cardiovasculares , Humanos , Imageamento por Ressonância Magnética , Fluxo Sanguíneo Regional
12.
Breast Care (Basel) ; 8(3): 221-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24415975

RESUMO

The International Consensus Conference on the treatment of primary breast cancer takes place every two years in St. Gallen, Switzerland. The panel in St. Gallen is composed of international experts from different countries. From a German perspective, it seems reasonable to interpret the voting results in the light of AGO-recommendations and S3-guidelines for everyday practice in Germany. Consequently, a team of eight breast cancer experts, of whom two are members of the international St. Gallen panel, commented on the voting results of the St. Gallen Consensus Conference (2013). The main topics at this year's St. Gallen conference were surgical issues of the breast and axilla, radio-therapeutic and systemic treatment options, and the clinical relevance of tumour biology. The clinical utility of multigene assays for supporting individual treatment decisions was also intensively discussed.

13.
Work ; 41 Suppl 1: 252-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22316731

RESUMO

At present, the number of the vehicle requirements has been continuously increasing. These requirements can be related to the customer as well as the technical requirements. Among these, the "feeling of space" of the occupants inside the vehicles can be regarded as one of the most important factors. In this respect, the driver and passengers should be able to experience positive feeling of space inside the vehicle. There are numerous factors that can influence the sense of space inside the vehicle. These include geometry (vehicle dimensions), light exposure, ambient lights, colors, material selection and material surface. Depending on the selection, the sense of space can be dramatically influenced by these factors. In general, human feeling is subjective and cannot be measured by any instrument. The measure can nevertheless be carried out by utilizing the method of subjective evaluation. Throughout the experiments, the method of evaluation is developed and the factors which can influence the interior feeling are analyzed. In this process, psychological perception, architectural aspects and anthropometry are considered and knowledge from the other domains is transferred in the form of a multidisciplinary approach. The experiments with an aim to evaluate the overall sense of space in the vehicle are carried out based on the physical mock up of BMW 1 series (E87). The space perception with different interior dimensions and anthropometric data of test persons are also analyzed. The use of Computer Aided Technology was shown by CATIA V5, PCMAN and RAMSIS. The results show a good correlation between the subjective evaluation and the geometric values.


Assuntos
Antropometria , Automóveis , Decoração de Interiores e Mobiliário , Percepção Espacial , Adolescente , Adulto , Comportamento do Consumidor , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
14.
Int J Cardiol ; 131(2): e59-60, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-17707527

RESUMO

Cardiac manifestations of hydatid cysts are rare and occur in about 0.2 to 3% of all cases of human hydatidosis. We report the case of a young man with a known 4-year old infection with Echinoccus granulosus. Cardiovascular magnetic resonance imaging (CMR) was performed and showed two cysts in the left ventricular wall. The smaller cyst had a thin, noncontinuous membrane to the left ventricle. The T1- and T2-weighted images showed an isointense signal of the cysts compared to blood; fat-suppressed images showed no fatty components. To highlight the potential small signal differences we assigned the contents of the gray images to red, green and blue channels of a conventional color image. Blood and the content of the cysts had the same color, making a connection between the cysts and the LV blood pool highly probable. This was confirmed by first pass perfusion imaging, which showed simultaneous contrast agent arrival in the left ventricular cavity and the cysts. Delayed enhancement (DE) revealed fibrotic tissue surrounding the cysts. MR seems to be the most complete method of diagnosing the disease, as anatomical structures, type of content of the cyst (liquid or solid) and its relation to the myocardium can be assessed within one study.


Assuntos
Meios de Contraste , Equinococose/diagnóstico , Equinococose/parasitologia , Echinococcus granulosus , Imageamento por Ressonância Magnética , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/parasitologia , Adulto , Animais , Echinococcus granulosus/crescimento & desenvolvimento , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
15.
JACC Cardiovasc Imaging ; 1(6): 729-38, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19356509

RESUMO

OBJECTIVES: To evaluate in vivo anatomical relationships between the coronary sinus-great cardiac vein (CS-GCV), the mitral valve annulus (MVA), and left circumflex coronary artery (LCX) with cardiovascular magnetic resonance. BACKGROUND: The CS-GCV has become an anatomical structure of interest because it provides a way of access to the heart for a number of interventional procedures. Previous reports demonstrate that the postulated close anatomical proximity of the CS-GCV to the MVA does not always hold true in patients, both in autopsy specimens and in vivo by computed tomography. METHODS: In 31 participants (24 volunteers and 7 patients; 15 men; 42 +/- 19 years), cardiovascular magnetic resonance was performed for noninvasive evaluation of the coronary sinus and of the coronary arteries using whole-heart imaging and intravascular contrast agents. Three-dimensional reconstructions, standard orthogonal planes, and unprocessed raw data were used to assess CS-GCV anatomy and its relation to the MVA and the LCX along their entire course. RESULTS: The CS-GCV was located behind the left atrium in all examined participants, at a minimum distance of 8.6 +/- 3.9 mm from the MVA. In 80% of the participants, the LCX crossed the CS-GCV inferiorly, between the CS-GCV and the MVA. The CS-GCV and the LCX had a parallel course for 26.2 +/- 23.0 mm, with great variability of location and length. In several participants, the CS-GCV had a long parallel course, but in other participants, the LCX crossed below the CS-GCV at a discrete point. CONCLUSIONS: In all participants, the CS-GCV coursed behind the left atrium rather than behind the MVA. In the majority of the participants, the LCX coursed between the CS-GCV and the MVA. These anatomical relationships should be kept in mind when referring a patient for interventional procedures requiring the access to the CS-GCV, and cardiovascular magnetic resonance might provide important information for the selection of candidates for these procedures.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/patologia , Angiografia por Ressonância Magnética , Valva Mitral/patologia , Adulto , Simulação por Computador , Seio Coronário/patologia , Estudos de Viabilidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Estudos Retrospectivos , Veias/patologia , Adulto Jovem
16.
Atherosclerosis ; 196(2): 523-31, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17603062

RESUMO

Hyperplasia and hypertrophy of fat cells can be found in obesity, and increased adiposity is associated with endothelial dysfunction as an early event of atherosclerosis. However, it is unclear whether human adipocytes directly influence endothelial function. To study the crosstalk between fat and endothelial cells, human umbilical venous endothelial cells (HUVECs), and human coronary artery endothelial cells (HCAECs) were cultured in infranatants (Adipo) of primary differentiated human adipocytes. Interestingly, incubation of HUVECs and HCAECs with Adipo significantly increased monocyte adhesion 7.3 and 2.2-fold, respectively. VCAM-1, ICAM-1, and E-selectin in HUVECs were upregulated 3.9, 3.0, and 9.5-fold, respectively, under these conditions. Furthermore, Adipo significantly stimulated NFkappaB activity 1.9-fold. The NFkappaB inhibitor MG-132 and heat inactivation significantly reversed Adipo-stimulated monocyte adhesion. TNFalpha-neutralizing antibodies partly reversed Adipo-induced monocyte adhesion. In contrast, thiazolidinedione-pretreatment of human adipocytes did not alter the effects of Adipo. Adipo did not show cytotoxic effects. Taken together, we demonstrate that endothelial dysfunction is induced by adipocyte-secreted factors via NFkappaB partly dependent on TNFalpha.


Assuntos
Adipócitos/metabolismo , Adipocinas/fisiologia , Endotélio Vascular/fisiologia , NF-kappa B/fisiologia , Adipócitos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Selectina E/biossíntese , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Leptina/farmacologia , Leupeptinas/farmacologia , Resistina/farmacologia , Rosiglitazona , Tiazolidinedionas/farmacologia , Fator de Necrose Tumoral alfa/fisiologia , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/biossíntese
17.
J Cardiovasc Magn Reson ; 7(2): 401-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15881521

RESUMO

PURPOSE: With current noninvasive techniques compromises have to be accepted for coronary imaging, e.g., partial coverage of the coronary artery tree. The aim of the study was to estimate the potential intrinsic error of partial coverage from a database of invasive angiograms. METHODS AND RESULTS: The localization and severity of coronary artery stenoses and, if percutaneous coronary intervention (PCI) was performed, the balloon and stent size were extracted from a large database of 21,335 selective coronary angiograms. Of stenoses with >50% diameter reduction, 31.4% were located in distal segments and minor side branches, constituting 28.8% of interventional treatment. In 5% of patients undergoing their first invasive angiogram, the most proximal relevant stenosis was found in a distal segment or minor side branch. Most interventions (83.5%) were performed in main coronary artery segments. CONCLUSION: Coronary artery stenoses were found and interventional treatment performed in all coronary segments. Therefore, noninvasive coronary imaging of only proximal and medial segments and major side branches is an inadequate strategy for complete diagnosis or as a guide to therapeutic decisions. However, the currently available noninvasive techniques allow the detection of relevant stenoses in 95% of patients with suspected coronary artery disease (CAD) to prepare for further invasive diagnostic and therapeutic planning.


Assuntos
Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão , Estenose Coronária/terapia , Bases de Dados como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Stents
18.
Plant J ; 42(3): 444-53, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15842628

RESUMO

We have generated a novel genetic system to visualize cell lineages in living tissues at high resolution. Heat shock was used to trigger the excision of a specific transposon and activation of a fluorescent marker gene. A histone-YFP marker was used to allow identification of cell lineages and easy counting of cells. Constitutive expression of a green fluorescent membrane protein was used to provide a precise outline of all surrounding cells. Marked lineages can be induced from specific cells within the organism by targeted laser irradiation, and the fate of the marked cells can be followed non-invasively. We have used the system to map cell lineages originating from the initials of primary and lateral roots in Arabidopsis. The lineage marking technique enabled us to measure the differential contribution of primary root pericycle cell files to developing lateral root primordia. The majority of cells in an emerging lateral root primordium derive from the central file of pericycle founder cells while off-centre founder cells contribute only a minor proliferation of tissue near the base of the root. The system shows great promise for the detailed study of cell division during morphogenesis.


Assuntos
Arabidopsis/citologia , Arabidopsis/crescimento & desenvolvimento , Linhagem da Célula/fisiologia , Botânica/métodos , Diferenciação Celular , Divisão Celular , Genes Reporter , Temperatura Alta , Lasers , Proteínas Luminescentes/metabolismo , Raízes de Plantas/citologia , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/metabolismo
19.
J Cardiovasc Magn Reson ; 6(4): 865-75, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15646890

RESUMO

BACKGROUND: Magnetic resonance coronary angiography (MRCA) has traditionally been performed using a Cartesian k-space data acquisition scheme. Radial k-space sampling is known to be less sensitive to motion artifacts. Thus, potential improvements may be achieved with radial k-space data acquisition using steady state free precession (SSFP) techniques. We directly compared SSFP three-dimensional (3D)-MRCA using radial and Cartesian data acquisition. METHODS: Forty-four consecutive patients with suspected coronary artery disease underwent free-breathing, navigator-corrected MRCA of the left or right coronary artery using SSFP (TR/TE/flip angle: 4.5 ms/2.3 ms/90 degrees) with radial and again with Cartesian k-space filling. Quantitative MRCA was performed with a dedicated multiplanar reformatting software to determine: visual score for image quality (low=1, high=4), vessel sharpness, visible vessel length, number of visible side branches, and average vessel diameter. Diagnostic accuracy for detection of > or = 50% coronary artery stenosis was calculated in comparison to invasive X-ray angiography. RESULTS: Radial data acquisition resulted in a significant (p<0.01) increase in vessel sharpness (55.6+/-7.2% vs. 45.9+/-7.0%) but a decrease in average vessel diameter (2.6+/-0.5 mm vs. 3.0+/-0.4 mm), number of visible side branches (2.1+/-1.1 vs. 3.0+/-1.7) and number of assessable coronary artery segments (66% vs. 73%) compared to Cartesian approach. There was no significant difference regarding the diagnostic accuracy (80.8% vs. 83.9%), the visual score (2.6+/-0.9 vs. 3.0+/-0.9) and the visible vessel length (92.1+/-36.0 mm vs. 99.9+/-32.4 mm). CONCLUSIONS: MRCA with radial k-space sampling appears to be on a par with Cartesian approach with respect to the diagnostic performance in an unselected patient population. Nevertheless, with current implementations, radial sampling is inferior to Cartesian sampling regarding the visualization of side branches despite better vessel sharpness.


Assuntos
Angiografia Coronária , Estenose Coronária/diagnóstico , Angiografia por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/patologia , Vasos Coronários/patologia , Feminino , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
20.
J Magn Reson Imaging ; 17(2): 153-62, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12541221

RESUMO

PURPOSE: To study pulsatile fluid flow in a physiologically realistic model of the human carotid bifurcation, and to derive wall shear stress (WSS) vectors. MATERIALS AND METHODS: WSS vectors were calculated from time-resolved 3D phase-contrast (PC) MRI measurements of the velocity field. The technique was first validated with sinusoidal flow in a straight tube, and then used in a model of a healthy human carotid bifurcation. Velocity measurements in the inflow and outflow regions were also used as boundary conditions for computational fluid dynamics (CFD) calculations of WSS, which were compared with those derived from MRI alone. RESULTS: The straight tube measurements gave WSS results that were within 15% of the theoretical value. WSS results for the phantom showed the main features expected from fluid dynamics, notably the low values in the bulb region of the internal carotid artery, with a return to ordered flow further downstream. MRI was not able to detect the high WSS values along the divider wall that were predicted by the CFD model. Otherwise, there was good general agreement between MRI and CFD. CONCLUSION: This is the first report of time-resolved WSS vectors estimated from 3D-MRI data. The technique worked well except in regions of disturbed flow, where the combination with CFD modeling is clearly advantageous.


Assuntos
Artérias Carótidas/fisiologia , Circulação Cerebrovascular , Imageamento por Ressonância Magnética , Modelos Cardiovasculares , Humanos , Imageamento Tridimensional , Imagens de Fantasmas , Fluxo Pulsátil
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