Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 106
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Immunity ; 52(6): 1075-1087.e8, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32445619

RESUMO

Enhancing immune cell functions in tumors remains a major challenge in cancer immunotherapy. Hypoxia is a common feature of solid tumors, and cells adapt by upregulating the transcription factor HIF-1α. Here, we defined the transcriptional landscape of mouse tumor-infiltrating natural killer (NK) cells by using single-cell RNA sequencing. Conditional deletion of Hif1a in NK cells resulted in reduced tumor growth, elevated expression of activation markers, effector molecules, and an enriched NF-κB pathway in tumor-infiltrating NK cells. Interleukin-18 (IL-18) from myeloid cells was required for NF-κB activation and the enhanced anti-tumor activity of Hif1a-/- NK cells. Extended culture with an HIF-1α inhibitor increased human NK cell responses. Low HIF1A expression was associated with high expression of IFNG in human tumor-infiltrating NK cells, and an enriched NK-IL18-IFNG signature in solid tumors correlated with increased overall patient survival. Thus, inhibition of HIF-1α unleashes NK cell anti-tumor activity and could be exploited for cancer therapy.


Assuntos
Citotoxicidade Imunológica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Animais , Biomarcadores , Biologia Computacional , Citocinas/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ativação Linfocitária/genética , Camundongos , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/mortalidade , Prognóstico , Análise de Célula Única , Transcriptoma , Microambiente Tumoral/imunologia
2.
Hepatology ; 77(4): 1211-1227, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35776660

RESUMO

BACKGROUND AND AIMS: In hereditary hemorrhagic telangiectasia (HHT), severe liver vascular malformations are associated with mutations in the Activin A Receptor-Like Type 1 ( ACVRL1 ) gene encoding ALK1, the receptor for bone morphogenetic protein (BMP) 9/BMP10, which regulates blood vessel development. Here, we established an HHT mouse model with exclusive liver involvement and adequate life expectancy to investigate ALK1 signaling in liver vessel formation and metabolic function. APPROACH AND RESULTS: Liver sinusoidal endothelial cell (LSEC)-selective Cre deleter line, Stab2-iCreF3 , was crossed with Acvrl1 -floxed mice to generate LSEC-specific Acvrl1 -deficient mice ( Alk1HEC-KO ). Alk1HEC-KO mice revealed hepatic vascular malformations and increased posthepatic flow, causing right ventricular volume overload. Transcriptomic analyses demonstrated induction of proangiogenic/tip cell gene sets and arterialization of hepatic vessels at the expense of LSEC and central venous identities. Loss of LSEC angiokines Wnt2 , Wnt9b , and R-spondin-3 ( Rspo3 ) led to disruption of metabolic liver zonation in Alk1HEC-KO mice and in liver specimens of patients with HHT. Furthermore, prion-like protein doppel ( Prnd ) and placental growth factor ( Pgf ) were upregulated in Alk1HEC-KO hepatic endothelial cells, representing candidates driving the organ-specific pathogenesis of HHT. In LSEC in vitro , stimulation or inhibition of ALK1 signaling counter-regulated Inhibitors of DNA binding (ID)1-3, known Alk1 transcriptional targets. Stimulation of ALK1 signaling and inhibition of ID1-3 function confirmed regulation of Wnt2 and Rspo3 by the BMP9/ALK1/ID axis. CONCLUSIONS: Hepatic endothelial ALK1 signaling protects from development of vascular malformations preserving organ-specific endothelial differentiation and angiocrine signaling. The long-term surviving Alk1HEC-KO HHT model offers opportunities to develop targeted therapies for this severe disease.


Assuntos
Telangiectasia Hemorrágica Hereditária , Camundongos , Feminino , Animais , Telangiectasia Hemorrágica Hereditária/genética , Células Endoteliais/metabolismo , Fator de Crescimento Placentário/metabolismo , Fígado/patologia , Transdução de Sinais , Fator 2 de Diferenciação de Crescimento/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo
3.
Graefes Arch Clin Exp Ophthalmol ; 262(6): 1819-1828, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38446204

RESUMO

PURPOSE: The aim of this study is to investigate the distribution of spherical equivalent and axial length in the general population and to analyze the influence of education on spherical equivalent with a focus on ocular biometric parameters. METHODS: The Gutenberg Health Study is a population-based cohort study in Mainz, Germany. Participants underwent comprehensive ophthalmologic examinations as part of the 5-year follow-up examination in 2012-2017 including genotyping. The spherical equivalent and axial length distributions were modeled with gaussian mixture models. Regression analysis (on person-individual level) was performed to analyze associations between biometric parameters and educational factors. Mendelian randomization analysis explored the causal effect between spherical equivalent, axial length, and education. Additionally, effect mediation analysis examined the link between spherical equivalent and education. RESULTS: A total of 8532 study participants were included (median age: 57 years, 49% female). The distribution of spherical equivalent and axial length follows a bi-Gaussian function, partially explained by the length of education (i.e., < 11 years education vs. 11-20 years). Mendelian randomization indicated an effect of education on refractive error using a genetic risk score of education as an instrument variable (- 0.35 diopters per SD increase in the instrument, 95% CI, - 0.64-0.05, p = 0.02) and an effect of education on axial length (0.63 mm per SD increase in the instrument, 95% CI, 0.22-1.04, p = 0.003). Spherical equivalent, axial length and anterior chamber depth were associated with length of education in regression analyses. Mediation analysis revealed that the association between spherical equivalent and education is mainly driven (70%) by alteration in axial length. CONCLUSIONS: The distribution of axial length and spherical equivalent is represented by subgroups of the population (bi-Gaussian). This distribution can be partially explained by length of education. The impact of education on spherical equivalent is mainly driven by alteration in axial length.


Assuntos
Comprimento Axial do Olho , Escolaridade , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Alemanha/epidemiologia , Comprimento Axial do Olho/patologia , Distribuição Normal , Biometria/métodos , Refração Ocular/fisiologia , Seguimentos , Erros de Refração/fisiopatologia , Erros de Refração/diagnóstico , Erros de Refração/genética , Idoso , Adulto
4.
Europace ; 25(1): 130-136, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36006798

RESUMO

AIMS: The incidence of in-hospital post-interventional complications and mortality after ablation of supraventricular tachycardia (SVT) vary among the type of procedure and most likely the experience of the centre. As ablation therapy of SVT is progressively being established as first-line therapy, further assessment of post-procedural complication rates is crucial for health care quality. METHODS AND RESULTS: We aimed at determining the incidence of in-hospital mortality and bleeding complications from SVT ablations in German high-volume electrophysiological centres between 2005 and 2020. All cases were registered by the German Diagnosis Related Groups-and the German Operation and Procedure Classification (OPS) system. A uniform search for SVT ablations from 2005 to 2020 with the same OPS codes defining the type of ablation/arrhythmia as well as the presence of a vascular complication, cardiac tamponade, and/or in-hospital death was performed. An overall of 47 610 ablations with 10 037 SVT ablations were registered from 2005 to 2020 among three high-volume centres. An overall complication rate of 0.5% (n = 38) was found [median age, 64; ±15 years; female n = 26 (68%)]. All-cause mortality was 0.02% (n = 2) and both patients had major prior co-morbidities precipitating a lethal outcome irrespective of the ablation procedure. Vascular complications occurred in 10 patients (0.1%), and cardiac tamponade was detected in 26 cases (0.3%). CONCLUSION: The present case-based analysis shows an overall low incidence of in-hospital complications after SVT ablation highlighting the overall very good safety profile of SVT ablations in high-volume centres. Further prospective analysis is still warranted to guarantee continuous quality control and optimal patient care.


Assuntos
Tamponamento Cardíaco , Ablação por Cateter , Taquicardia Supraventricular , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Mortalidade Hospitalar , Tamponamento Cardíaco/epidemiologia , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/cirurgia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos
5.
Europace ; 26(1)2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38102318

RESUMO

AIMS: In-hospital complications of catheter ablation for atrial fibrillation (AF), atrial flutter (AFL), and ventricular tachycardia (VT) may be overestimated by analyses of administrative data. METHODS AND RESULTS: We determined the incidences of in-hospital mortality, major bleeding, and stroke around AF, AFL, and VT ablations in four German tertiary centres between 2005 and 2020. All cases were coded by the G-DRG- and OPS-systems. Uniform code search terms were applied defining both the types of ablations for AF, AFL, and VT and the occurrence of major adverse events including femoral vascular complications, iatrogenic tamponade, stroke, and in-hospital death. Importantly, all complications were individually reviewed based on patient-level source records. Overall, 43 031 ablations were analysed (30 361 AF; 9364 AFL; 3306 VT). The number of ablations/year more than doubled from 2005 (n = 1569) to 2020 (n = 3317) with 3 times and 2.5 times more AF and VT ablations in 2020 (n = 2404 and n = 301, respectively) as compared to 2005 (n = 817 and n = 120, respectively), but a rather stable number of AFL ablations (n = 554 vs. n = 612). Major peri-procedural complications occurred in 594 (1.4%) patients. Complication rates were 1.1% (n = 325) for AF, 1.0% (n = 95) for AFL, and 5.3% (n = 175) for VT. With an increase in complex AF/VT procedures, the overall complication rate significantly increased (0.76% in 2005 vs. 1.81% in 2020; P = 0.004); but remained low over time. Following patient-adjudication, all in-hospital cardiac tamponades (0.7%) and strokes (0.2%) were related to ablation. Major femoral vascular complications requiring surgical intervention occurred in 0.4% of all patients. The in-hospital mortality rate adjudicated to be ablation-related was lower than the coded mortality rate: AF: 0.03% vs. 0.04%; AFL: 0.04% vs. 0.14%; VT: 0.42% vs. 1.48%. CONCLUSION: Major adverse events are low and comparable after catheter ablation for AFL and AF (∼1.0%), whereas they are five times higher for VT ablations. In the presence of an increase in complex ablation procedures, a moderate but significant increase in overall complications from 2005-20 was observed. Individual case analysis demonstrated a lower than coded ablation-related in-hospital mortality. This highlights the importance of individual case adjudication when analysing administrative data.


Assuntos
Fibrilação Atrial , Flutter Atrial , Ablação por Cateter , Acidente Vascular Cerebral , Taquicardia Ventricular , Humanos , Mortalidade Hospitalar , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/epidemiologia , Flutter Atrial/diagnóstico , Flutter Atrial/cirurgia , Flutter Atrial/etiologia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/cirurgia , Hospitais , Acidente Vascular Cerebral/epidemiologia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Resultado do Tratamento
6.
Graefes Arch Clin Exp Ophthalmol ; 261(11): 3241-3247, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37314521

RESUMO

Keratoconus appears to be a rare corneal disease with a prevalence previously estimated at 1:2000. The aim of our study was to investigate the prevalence of keratoconus in a large German cohort and to evaluate possible associated factors. METHOD: In the population-based, prospective, monocentric cohort study, Gutenberg Health Study, 12,423 subjects aged 40-80 years were examined at the 5-year follow-up. Subjects underwent a detailed medical history and a general and ophthalmologic examination including Scheimpflug imaging. Keratoconus diagnosis was performed in two steps: all subjects with conspicuous TKC analysis of corneal tomography were included in further grading. Prevalence and 95% confidence intervals were calculated. Logistic regression analysis was carried out to investigate association with age, sex, BMI, thyroid hormone, smoking, diabetes, arterial hypertension, atopy, allergy, steroid use, sleep apnea, asthma, and depression. RESULTS: Of 10,419 subjects, 75 eyes of 51 subjects were classified as having keratoconus. The prevalence for keratoconus in the German cohort was 0.49% (1:204; 95% CI: 0.36-0.64%) and was approximately equally distributed across the age decades. No gender predisposition could be demonstrated. Logistic regression showed no association between keratoconus and age, sex, BMI, thyroid hormone, smoking, diabetes, arterial hypertension, atopy, allergy, steroid use, sleep apnea, asthma, and depression in our sample. CONCLUSION: The prevalence of keratoconus disease in a mainly Caucasian population is approximately tenfold higher than previously reported in the literature using latest technologies (Scheimpflug imaging). Contrary to previous assumptions, we did not find associations with sex, existing atopy, thyroid dysfunction, diabetes, smoking, and depression.

7.
J Transl Med ; 20(1): 62, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35109875

RESUMO

BACKGROUND: Cutaneous melanoma exhibits heterogeneous metastatic patterns and prognosis. In this regard, liver metastasis, which is detected in ~ 10-20% of stage 4 patients, came to the fore of melanoma research, as it recently evolved as decisive indicator of treatment resistance to immune checkpoint inhibition. METHODS: Hepatic metastases were induced by intrasplenic injection of five different murine melanoma cell lines. The efficiencies of hepatic colonization, morphologic patterns, gene expression profiles and degree of vascularization were analyzed and Sorafenib was applied as anti-angiogenic treatment. RESULTS: WT31 melanoma showed the highest efficiency of hepatic colonization, while intermediate efficiencies were observed for B16F10 and RET, and low efficiencies for D4M and HCmel12. RNAseq-based gene expression profiles of high and intermediate metastatic melanomas in comparison to low metastatic melanomas indicated that this efficiency predominantly associates with gene clusters involved in cell migration and angiogenesis. Indeed, heterogeneous vascularization patterns were found in the five models. Although the degree of vascularization of WT31 and B16F10 metastases differed, both showed a strong response to Sorafenib with a successful abrogation of the vascularization. CONCLUSION: Our data indicate that molecular heterogeneity of melanomas can be associated with phenotypic and prognostic features of hepatic metastasis paving the way for organ-specific anti-angiogenic therapeutic approaches.


Assuntos
Neoplasias Hepáticas , Melanoma , Neoplasias Cutâneas , Animais , Humanos , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Camundongos , Metástase Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neoplasias Cutâneas/patologia
8.
Cancer Cell Int ; 22(1): 398, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36496412

RESUMO

BACKGROUND: Hyaluronan receptor LYVE-1 is expressed by liver sinusoidal endothelial cells (LSEC), lymphatic endothelial cells and specialized macrophages. Besides binding to hyaluronan, LYVE-1 can mediate adhesion of leukocytes and cancer cells to endothelial cells. Here, we assessed the impact of LYVE-1 on physiological liver functions and metastasis. METHODS: Mice with deficiency of Lyve-1 (Lyve-1-KO) were analyzed using histology, immunofluorescence, microarray analysis, plasma proteomics and flow cytometry. Liver metastasis was studied by intrasplenic/intravenous injection of melanoma (B16F10 luc2, WT31) or colorectal carcinoma (MC38). RESULTS: Hepatic architecture, liver size, endothelial differentiation and angiocrine functions were unaltered in Lyve-1-KO. Hyaluronan plasma levels were significantly increased in Lyve-1-KO. Besides, plasma proteomics revealed increased carbonic anhydrase-2 and decreased FXIIIA. Furthermore, gene expression analysis of LSEC indicated regulation of immunological pathways. Therefore, liver metastasis of highly and weakly immunogenic tumors, i.e. melanoma and colorectal carcinoma (CRC), was analyzed. Hepatic metastasis of B16F10 luc2 and WT31 melanoma cells, but not MC38 CRC cells, was significantly reduced in Lyve-1-KO mice. In vivo retention assays with B16F10 luc2 cells were unaltered between Lyve-1-KO and control mice. However, in tumor-free Lyve-1-KO livers numbers of hepatic CD4+, CD8+ and regulatory T cells were increased. In addition, iron deposition was found in F4/80+ liver macrophages known to exert pro-inflammatory effects. CONCLUSION: Lyve-1 deficiency controlled hepatic metastasis in a tumor cell-specific manner leading to reduced growth of hepatic metastases of melanoma, but not CRC. Anti-tumorigenic effects are likely due to enhancement of the premetastatic hepatic immune microenvironment influencing early liver metastasis formation.

9.
Angiogenesis ; 24(2): 289-310, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33745018

RESUMO

'Angiodiversity' refers to the structural and functional heterogeneity of endothelial cells (EC) along the segments of the vascular tree and especially within the microvascular beds of different organs. Organotypically differentiated EC ranging from continuous, barrier-forming endothelium to discontinuous, fenestrated endothelium perform organ-specific functions such as the maintenance of the tightly sealed blood-brain barrier or the clearance of macromolecular waste products from the peripheral blood by liver EC-expressed scavenger receptors. The microvascular bed of the liver, composed of discontinuous, fenestrated liver sinusoidal endothelial cells (LSEC), is a prime example of organ-specific angiodiversity. Anatomy and development of LSEC have been extensively studied by electron microscopy as well as linage-tracing experiments. Recent advances in cell isolation and bulk transcriptomics or single-cell RNA sequencing techniques allowed the identification of distinct LSEC molecular programs and have led to the identification of LSEC subpopulations. LSEC execute homeostatic functions such as fine tuning the vascular tone, clearing noxious substances from the circulation, and modulating immunoregulatory mechanisms. In recent years, the identification and functional analysis of LSEC-derived angiocrine signals, which control liver homeostasis and disease pathogenesis in an instructive manner, marks a major change of paradigm in the understanding of liver function in health and disease. This review summarizes recent advances in the understanding of liver vascular angiodiversity and the functional consequences resulting thereof.


Assuntos
Células Endoteliais/metabolismo , Hepatopatias/metabolismo , Fígado/metabolismo , RNA-Seq , Análise de Célula Única , Animais , Células Endoteliais/patologia , Humanos , Fígado/patologia , Hepatopatias/genética , Hepatopatias/patologia , Especificidade de Órgãos/genética
10.
J Hepatol ; 74(2): 380-393, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32916216

RESUMO

BACKGROUND & AIMS: Angiocrine signaling by liver sinusoidal endothelial cells (LSECs) regulates hepatic functions such as growth, metabolic maturation, and regeneration. Recently, we identified GATA4 as the master regulator of LSEC specification during development. Herein, we studied the role of endothelial GATA4 in the adult liver and in hepatic pathogenesis. METHODS: We generated adult Clec4g-icretg/0xGata4fl/fl (Gata4LSEC-KO) mice with LSEC-specific depletion of Gata4. Livers were analyzed by histology, electron microscopy, immunohistochemistry/immunofluorescence, in situ hybridization, and LSECs were isolated for gene expression profiling, ChIP- and ATAC-sequencing. Partial hepatectomy was performed to assess regeneration. We used choline-deficient, l-amino acid-defined (CDAA) diet and chronic carbon tetrachloride exposure to model liver fibrosis. Human single cell RNA-seq data sets were analyzed for endothelial alterations in healthy and cirrhotic livers. RESULTS: Genetic Gata4 deficiency in LSECs of adult mice caused perisinusoidal liver fibrosis, hepatopathy and impaired liver regeneration. Sinusoidal capillarization and LSEC-to-continuous endothelial transdifferentiation were accompanied by a profibrotic angiocrine switch involving de novo endothelial expression of hepatic stellate cell-activating cytokine PDGFB. Increased chromatin accessibility and amplification by activated MYC mediated angiocrine Pdgfb expression. As observed in Gata4LSEC-KO livers, CDAA diet-induced perisinusoidal liver fibrosis was associated with GATA4 repression, MYC activation and a profibrotic angiocrine switch in LSECs. Comparison of CDAA-fed Gata4LSEC-KO and control mice demonstrated that endothelial GATA4 indeed protects against dietary-induced perisinusoidal liver fibrosis. In human cirrhotic livers, GATA4-positive LSECs and endothelial GATA4 target genes were reduced, while non-LSEC endothelial cells and MYC target genes including PDGFB were enriched. CONCLUSIONS: Endothelial GATA4 protects against perisinusoidal liver fibrosis by repressing MYC activation and profibrotic angiocrine signaling at the chromatin level. Therapies targeting the GATA4/MYC/PDGFB/PDGFRß axis offer a promising strategy for prevention and treatment of liver fibrosis. LAY SUMMARY: The liver vasculature is supposed to play a major role in the development of liver fibrosis and cirrhosis, which can lead to liver failure and liver cancer. Herein, we discovered that structural and transcriptional changes induced by genetic deletion of the transcription factor GATA4 in the hepatic endothelium were sufficient to cause liver fibrosis. Activation of the transcription factor MYC and de novo expression of the "angiocrine" growth factor PDGFB were identified as downstream drivers of fibrosis and as potential therapeutic targets for this potentially fatal disease.


Assuntos
Células Endoteliais/metabolismo , Fator de Transcrição GATA4/metabolismo , Cirrose Hepática , Fígado , Linfocinas , Fator de Crescimento Derivado de Plaquetas , Animais , Cromatina/metabolismo , Descoberta de Drogas , Perfilação da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Humanos , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/prevenção & controle , Regeneração Hepática/fisiologia , Linfocinas/genética , Linfocinas/metabolismo , Camundongos , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Dedos de Zinco
11.
Am J Pathol ; 190(2): 358-371, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31783007

RESUMO

Liver sinusoidal endothelial cells (LSECs) control organ functions, metabolism, and development through the secretion of angiokines. LSECs express hepatocyte growth factor (Hgf), which is involved in prenatal development, metabolic homeostasis, and liver regeneration. This study aimed to elucidate the precise contribution of LSEC-derived Hgf in physiological homeostasis and liver regeneration. Stab2-iCretg/wt;Hgffl/fl (HgfΔLSEC) mice were generated to abrogate Hgf expression selectively in LSECs from early fetal development onwards, to study global development, metabolic and endothelial zonation, and organ functions as well as liver regeneration in response to 70% partial hepatectomy (PH). Although zonation and liver/body weight ratios were not altered, total body weight and total liver weight were reduced in HgfΔLSEC. Necrotic organ damage was more marked in HgfΔLSEC mice, and regeneration was delayed 72 hours after PH. This was associated with decreased hepatocyte proliferation at 48 hours after PH. Molecularly, HgfΔLSEC mice showed down-regulation of Hgf/c-Met signaling and decreased expression of Deptor in hepatocytes. In vitro knockdown of Deptor was associated with decreased proliferation. Therefore, angiocrine Hgf controls hepatocyte proliferation and susceptibility to necrosis after partial hepatectomy via the Hgf/c-Met axis involving Deptor to prevent excessive organ damage.


Assuntos
Tamanho Corporal , Proliferação de Células , Fator de Crescimento de Hepatócito/fisiologia , Hepatócitos/citologia , Hepatopatias/prevenção & controle , Regeneração Hepática , Organogênese/fisiologia , Animais , Moléculas de Adesão Celular Neuronais/fisiologia , Endotélio/citologia , Endotélio/metabolismo , Feminino , Hepatectomia , Hepatócitos/fisiologia , Homeostase , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Camundongos , Camundongos Knockout , Comunicação Parácrina , Transdução de Sinais
12.
Graefes Arch Clin Exp Ophthalmol ; 259(12): 3605-3611, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34236473

RESUMO

AIMS: The aim of this study is to evaluate retinal and optic nerve head (ONH) perfusion in patients with systolic chronic heart failure (CHF) compared to healthy control subjects. METHODS: Twenty-seven eyes of 27 patients with CHF (study group) and 31 eyes of 31 healthy subjects (control group) were prospectively included in this study. CHF Patients had a left ventricular ejection fraction (LVEF) < 50% and were classified by New York Heart Association (NYHA) class. OCT-A was performed using RTVue XR Avanti with AngioVue (Optovue, Inc, Fremont, CA, USA). The area of the foveal avascular zone (FAZ) and flow density (FD) data were extracted and analyzed. RESULTS: There was no significant difference in the signal strength index between the study group (group 1) and the control group (group 2) (ONH: p = 0.015; macula: p = 0.703). The difference in the area of the foveal avascular zone between the two groups was also not significant (p = 0.726). The flow density (whole en face) in the ONH (RPC) in group 1 was significantly lower compared to control (group 1 = 48.40 ± 2.48 (49.0 [46.7, 50.3]); group 2 = 50.15 ± 1.85 (50.6 [48.5, 51.70]); p = 0.008). There was a significant and strong correlation between LVEF and the macular flow density (whole en face) (superficial: rs = 0.605 deep: rs = 0.425, p < 0.01). CONCLUSIONS: Patients with CHF showed reduced flow density compared with healthy controls. The reduced FD correlated with the LVEF and the functional (NYHA) class. Retinal perfusion as measured using OCTA might provide an insight into the global microperfusion and hemodynamic state of heart failure patients.


Assuntos
Vasos Retinianos , Tomografia de Coerência Óptica , Angiofluoresceinografia , Humanos , Perfusão , Vasos Retinianos/diagnóstico por imagem , Volume Sistólico , Função Ventricular Esquerda
13.
Hepatology ; 68(2): 707-722, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29059455

RESUMO

Postnatal liver development is characterized by hepatocyte growth, proliferation, and functional maturation. Notably, canonical Wnt signaling in hepatocytes has been identified as an important regulator of final adult liver size and metabolic liver zonation. The cellular origin of Wnt ligands responsible for homeostatic liver/body weight ratio (LW/BW) remained unclear, which was also attributable to a lack of suitable endothelial Cre driver mice. To comprehensively analyze the effects of hepatic angiocrine Wnt signaling on liver development and metabolic functions, we used endothelial subtype-specific Stab2-Cre driver mice to delete Wls from hepatic endothelial cells (HECs). The resultant Stab2-Cretg/wt ;Wlsfl/fl (Wls-HECKO) mice were viable, but showed a significantly reduced LW/BW. Specifically, ablation of angiocrine Wnt signaling impaired metabolic zonation in the liver, as shown by loss of pericentral, ß-catenin-dependent target genes such as glutamine synthase (Glul), RhBg, Axin2, and cytochrome P450 2E1, as well as by extended expression of periportal genes such as arginase 1. Furthermore, endothelial subtype-specific expression of a c-terminally YFP-tagged Wls fusion protein in Wls-HECKO mice (Stab2-Cretg/wt ;Wlsfl/fl ;Rosa26:Wls-YFPfl/wt [Wls-rescue]) restored metabolic liver zonation. Interestingly, lipid metabolism was altered in Wls-HECKO mice exhibiting significantly reduced plasma cholesterol levels, while maintaining normal plasma triglyceride and blood glucose concentrations. On the contrary, zonal expression of Endomucin, LYVE1, and other markers of HEC heterogeneity were not altered in Wls-HECKO livers. CONCLUSION: Angiocrine Wnt signaling controls liver growth as well as development of metabolic liver zonation in mice, whereas intrahepatic HEC zonation is not affected. (Hepatology 2017).


Assuntos
Células Endoteliais/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Via de Sinalização Wnt/genética , Animais , Imunofluorescência , Técnicas de Genotipagem , Homeostase/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Metabolismo dos Lipídeos/fisiologia , Fígado/crescimento & desenvolvimento , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Wnt/metabolismo
14.
Blood ; 129(4): 415-419, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-27903529

RESUMO

Microvascular endothelial cells (ECs) display a high degree of phenotypic and functional heterogeneity among different organs. Organ-specific ECs control their tissue microenvironment by angiocrine factors in health and disease. Liver sinusoidal endothelial cells (LSECs) are uniquely differentiated to fulfill important organ-specific functions in development, under homeostatic conditions, and in regeneration and liver pathology. Recently, Bmp2 has been identified by us as an organ-specific angiokine derived from LSECs. To study angiocrine Bmp2 signaling in the liver, we conditionally deleted Bmp2 in LSECs using EC subtype-specific Stab2-Cre mice. Genetic inactivation of hepatic angiocrine Bmp2 signaling in Stab2-Cre;Bmp2fl/fl (Bmp2LSECKO) mice caused massive iron overload in the liver and increased serum iron levels and iron deposition in several organs similar to classic hereditary hemochromatosis. Iron overload was mediated by decreased hepatic expression of hepcidin, a key regulator of iron homeostasis. Thus, angiocrine Bmp2 signaling within the hepatic vascular niche represents a constitutive pathway indispensable for iron homeostasis in vivo that is nonredundant with Bmp6. Notably, we demonstrate that organ-specific angiocrine signaling is essential not only for the homeostasis of the respective organ but also for the homeostasis of the whole organism.


Assuntos
Proteína Morfogenética Óssea 2/genética , Células Endoteliais/metabolismo , Hemocromatose/genética , Hepcidinas/genética , Homeostase/genética , Ferro/metabolismo , Fígado/metabolismo , Animais , Proteína Morfogenética Óssea 2/deficiência , Proteína Morfogenética Óssea 6/genética , Proteína Morfogenética Óssea 6/metabolismo , Capilares/metabolismo , Capilares/patologia , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Células Endoteliais/patologia , Feminino , Regulação da Expressão Gênica , Hemocromatose/metabolismo , Hemocromatose/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepcidinas/metabolismo , Integrases/genética , Integrases/metabolismo , Fígado/irrigação sanguínea , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Comunicação Parácrina , Transdução de Sinais , Transcrição Gênica
15.
J Cutan Med Surg ; 23(4): 413-420, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179746

RESUMO

OBJECTIVES: It is uncertain whether dermal regeneration templates (DRTs) are helpful to reconstruct nasal defects. The aim of this study was to assess whether the aesthetic subunits determine the outcome. METHODS: In this unicentric, retrospective study, the surgical procedures and outcomes of patients who received DRTs to reconstruct nasal defects were assessed and compared with the involved aesthetic subunits. RESULTS: DRTs were used for reconstruction of 36 nasal defects in 35 patients with involvement of 76 aesthetic subunits: nasal sidewall (n = 21), nasal ala (n = 13), nasal tip/columella (n = 12, n = 1, respectively), nasal dorsum (n = 12), and extranasal aesthetic areas (n = 17). Fifty-eight nasal and 8 extranasal aesthetic subunits were reconstructed with DRTs, 10 subunits with a flap. Twenty-nine of 36 defects healed without any complications (80.5%). All reconstructed nasal tips/columella and the nasal dorsa healed without any complications. Region-specific complications were retraction of the ala rim (4/12; 33.3% of the patients with involvement of the nasal ala) and the formation of a fistula in the nasal sidewall (1/21; 4.8%). Region-specific complications of extranasal subunits were the development of an ectropium (2/3; 66.7% of the patients with involvement of the lower lid). CONCLUSIONS: DRTs can be helpful to reconstruct nasal defects. However, if the defect involves the aesthetic subunits nasal ala or the infraorbital region, different techniques should be preferred.


Assuntos
Deformidades Adquiridas Nasais/cirurgia , Neoplasias Nasais/cirurgia , Rinoplastia/métodos , Neoplasias Cutâneas/cirurgia , Pele Artificial , Ferida Cirúrgica/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sulfatos de Condroitina/uso terapêutico , Colágeno/uso terapêutico , Elastina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante de Pele , Retalhos Cirúrgicos , Resultado do Tratamento
16.
Biochem Biophys Res Commun ; 497(1): 32-38, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29408502

RESUMO

Endothelial cells (EC) along the vascular tree exhibit organ-specific angiodiversity. Compared to most other ECs, liver sinusoidal endothelial cells (LSEC) that constitute the organ-specific microvasculature of the liver are morphologically and functionally unique. Previously, we showed that transcription factor Gata4 acts as a master regulator controlling LSEC differentiation. Upon analysis of the molecular signature of LSEC, we identified GPR182 as a potential LSEC-specific orphan G-protein coupled receptor (GPCR). Here, we demonstrate that GPR182 is expressed by LSEC and by EC with sinusoidal differentiation in spleen, lymph node and bone marrow in healthy human tissues. In a tissue microarray analysis of human hepatocellular carcinoma (HCC) samples, endothelial GPR182 expression was significantly reduced in tumor samples compared to peritumoral liver tissue samples (p = 0.0105). Loss of endothelial GPR182 expression was also seen in fibrotic and cirrhotic liver tissues. In vitro, GPR182 differentially regulated canonical GPCR signaling pathways as shown using reporter luciferase assays in HEK293T cells. Whereas ERK and RhoA signaling were inhibited, CREB and Calcium signaling were activated by ectopic GPR182 overexpression. Our data demonstrate that GPR182 is an endothelial subtype-specific marker for human sinusoidal EC of the liver, spleen, lymph node and bone marrow. In addition, we provide evidence for GPR182-dependent downstream signaling via ERK and SRF pathways that may be involved in regulating endothelial subtype-specific sinusoidal differentiation and sinusoidal functions such as permeability.


Assuntos
Diferenciação Celular/fisiologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Neovascularização Fisiológica/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , Biomarcadores/metabolismo , Células Cultivadas , Humanos , Especificidade de Órgãos
17.
Europace ; 18(5): 696-701, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26705559

RESUMO

AIMS: The second-generation multi-electrode-phased radiofrequency pulmonary vein ablation catheter (PVAC GOLD(®)) was redesigned with the intent to improve its safety and efficacy. METHODS AND RESULTS: Using a prospectively designed single-centre database, we retrospectively analysed 128 consecutive patients (102 paroxysmal and 43 female) who underwent their first pulmonary vein isolation with the PVAC GOLD(®). The analysis focused on procedural data as well as in-hospital complications. Baseline characteristics of the patient collective were as follows: mean age 57.9 years, mean CHA2DS2-VASC was 1.73 ± 1.30; structural heart disease was present in seven patients. The PVAC GOLD(®) exhibited procedure durations of 123.1 min ± 27.9, duration of energy delivery was 18.3 min ± 11.4, and fluoroscopy duration was 16.0 min ± 7.7. The redesigned catheter shows major complication [major bleeding, transitory ischaemic attack (TIA), and pericardial tamponade] rates of 2.3% (n = 3). The overall rate of adverse events was 5.4% (n = 7). Bleeding complications were observed in three patients (2.3%), in particular there were two cases (1.6%) of minor bleeding and one case (0.8%) of major bleeding. Two patients suffered pericardial effusion, but there was no need for pericardiocentesis. Besides one TIA, there was no other thrombo-embolic event. Furthermore, one case of post-procedural fever was observed. No deaths, stroke, or haemorrhagic shock occurred. Of the 510 pulmonary veins, 508 could be reached with the PVAC GOLD(®) device using a non-steerable long sheath. CONCLUSION: The PVAC GOLD(®) seems to have an acceptable safety profile. The handling is comparable with the previous generation PVAC(®).


Assuntos
Fibrilação Atrial/terapia , Ablação por Cateter/instrumentação , Veias Pulmonares/cirurgia , Idoso , Antitrombinas/uso terapêutico , Ablação por Cateter/efeitos adversos , Dabigatrana/uso terapêutico , Bases de Dados Factuais , Eletrodos Implantados/efeitos adversos , Desenho de Equipamento , Europa (Continente) , Inibidores do Fator Xa/uso terapêutico , Feminino , Hemorragia/etiologia , Humanos , Ataque Isquêmico Transitório/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Rivaroxabana/uso terapêutico , Resultado do Tratamento
19.
Hum Brain Mapp ; 36(1): 354-66, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25213204

RESUMO

Schizophrenia is a complex psychiatric disorder characterized by disabling symptoms and cognitive deficit. Recent neuroimaging findings suggest that large parts of the brain are affected by the disease, and that the capacity of functional integration between brain areas is decreased. In this study we questioned (i) which brain areas underlie the loss of network integration properties observed in the pathology, (ii) what is the topological role of the affected regions within the overall brain network and how this topological status might be altered in patients, and (iii) how white matter properties of tracts connecting affected regions may be disrupted. We acquired diffusion spectrum imaging (a technique sensitive to fiber crossing and slow diffusion compartment) data from 16 schizophrenia patients and 15 healthy controls, and investigated their weighted brain networks. The global connectivity analysis confirmed that patients present disrupted integration and segregation properties. The nodal analysis allowed identifying a distributed set of brain nodes affected in the pathology, including hubs and peripheral areas. To characterize the topological role of this affected core, we investigated the brain network shortest paths layout, and quantified the network damage after targeted attack toward the affected core. The centrality of the affected core was compromised in patients. Moreover the connectivity strength within the affected core, quantified with generalized fractional anisotropy and apparent diffusion coefficient, was altered in patients. Taken together, these findings suggest that the structural alterations and topological decentralization of the affected core might be major mechanisms underlying the schizophrenia dysconnectivity disorder.


Assuntos
Encéfalo/patologia , Conectoma , Esquizofrenia/patologia , Substância Branca/patologia , Adulto , Anisotropia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/patologia , Vias Neurais/patologia
20.
Langenbecks Arch Surg ; 400(7): 837-41, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26149078

RESUMO

BACKGROUND: Elective pancreatic surgery can be carried out with mortality rates below 5% in specialized centers today. Only few data exist on pancreatic resections in emergency situations. The aim of the study was to characterize indications, procedures, and outcome of emergency pancreatic surgery in a tertiary center. METHODS: Prospectively collected data of all patients undergoing pancreatic operations at the authors' institution between October 2001 and December 2012 were analyzed regarding primary emergency operations in terms of indications, procedures, perioperative complications, and outcome. Emergency operations after preceding resections were excluded from the analysis. RESULTS: Twenty-three emergency operations were performed during the observation period. Indications were duodenal perforation (n = 8), upper GI bleeding (n = 6), complicated pseudocysts (n = 3), bile duct perforation (n = 2), pancreatic bleeding after blunt abdominal trauma (n = 1), pancreatic stent perforation (n = 1), necrotizing cholecystitis (n = 1), and ileus (n = 1). Procedures included partial and total duodeno-pancreatectomy (n = 15), cystojejunostomy (n = 2), distal pancreatectomy (n = 4), reconstruction of the ampulla Vateri (n = 1), and duodenectomy (n = 1). Median intraoperative blood loss was 750 (200-2500) ml and OP time 4.25 (1.75-9.25) h. Mean ICU stay was 21.3 (1-80) days with an overall surgical morbidity of 52.2%. Overall in-hospital mortality was 34.8% (8/23 pat.). CONCLUSIONS: Emergency pancreatic operations are infrequent and mainly performed due to duodenal perforation or bleeding; blunt abdominal trauma is rarely leading to emergency pancreas resections. They are associated with an increased morbidity and mortality and require a high level of surgical as well as interdisciplinary experience. Perioperative anesthesiological care and interventional radiological complication management are essential to improve outcome in this selective patient collective.


Assuntos
Tratamento de Emergência/mortalidade , Mortalidade Hospitalar/tendências , Pancreatectomia/mortalidade , Segurança do Paciente , Complicações Pós-Operatórias/mortalidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Procedimentos Cirúrgicos Eletivos/métodos , Procedimentos Cirúrgicos Eletivos/mortalidade , Emergências , Tratamento de Emergência/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Complicações Pós-Operatórias/fisiopatologia , Reoperação/métodos , Reoperação/mortalidade , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA