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1.
JPRAS Open ; 40: 360-374, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38770115

RESUMEN

Despite the growing use of autologous breast reconstruction with medial thigh-based free flaps, such as transverse upper gracilis (TMG) or profunda artery perforator (PAP) flaps, these procedures are infrequently performed on patients with obesity. This systematic review and meta-analysis aimed to compare the frequency of seroma occurrence, a common complication after medial thigh flap surgery. Comparison was performed between TMG and PAP flaps, as well as medial thigh lifts (MTL), a procedure with a similar operative technique but which is typically offered to patients with a higher body mass index (BMI). Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, we analyzed EMBASE, PUBMED, and MEDLINE data (English/German). The primary outcomes assessed were occurrence of seroma, as well as hematoma and wound dehiscence. Subgroup analyses explored age, BMI, and various surgical factors. This meta-analysis incorporated 28 studies, totaling 1096 patients. MTL patients had significantly higher BMIs, whereas seroma rates were similar among TMG, PAP, and MTL patients. The incidence of hematoma and wound dehiscence was also similar across the groups. In the metaregression analysis, factors such as age and BMI showed no significant correlation with seroma occurrence in all groups. This systematic review and meta-analysis identified comparable rates of seroma formation after TMG flap, PAP flap, and MTL procedures. Considering that this phenomenon occurred despite the elevated BMI of the MTL group, we propose that patients with higher BMI need not be excluded as candidates for autologous medial thigh-based breast reconstruction. Hence, these procedures should not be limited to small- to medium-sized breasts. Large-scale prospective studies are imperative to validate these conclusions and reveal the underlying factors contributing to seroma formation.

2.
Sci Rep ; 10(1): 5379, 2020 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-32214151

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is the most common kidney cancer. Prognosis for ccRCC is generally poor since it is largely resistant to chemo- and radiotherapy. Many studies suggested that cancer stem cells/tumor initiating cells (CSCs/TICs) are responsible for development of tumor, disease progression, aggressiveness, metastasis and drug resistance. However, tumorigenic potential of CSCs/TICs isolated from established RCC cell lines - basic ccRCC research model - has never been investigated in vivo. CD105+, CD105-, CD44+ and CD44- as well as CD44-/CD105- CD44+/CD105+ and CD44-/CD105+ cells were isolated from Caki-1 RCC cell line, confirming coexistence of multiple subpopulations of stem-related phenotype in stable cell line. Sorted cells were injected subcutaneously into NOD SCID mice and tumor growth was monitored with MRI and PET/CT. Tumor growth was observed after implantation of CD105+, CD44+, CD44-, CD44-/CD105+ and CD44-/CD105- but not CD105- or CD44+/CD105+. Implantation of CD44-/CD105- cells induced tumors that were characterized by longer T1 and distinct metabolic pattern than other tumors. All the tumors were characterized by low uptake of [18F]FDG. CD105+ and CD44- tumors expresses Nanog and Oct-4, while CD44- tumors additionally expressed endothelial cell marker - CD31.


Asunto(s)
Carcinoma de Células Renales/inmunología , Endoglina/inmunología , Receptores de Hialuranos/inmunología , Animales , Biomarcadores de Tumor/inmunología , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Separación Celular , Endoglina/metabolismo , Humanos , Receptores de Hialuranos/metabolismo , Neoplasias Renales/inmunología , Neoplasias Renales/patología , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Pronóstico
3.
ACS Omega ; 2(7): 3616-3631, 2017 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-30023699

RESUMEN

The cross-linked pentapeptides (2R,7R)-diaminooctanedioyl-bis(Tyr-Arg-Leu-Arg-Tyr-amide) ((2R,7R)-BVD-74D, (2R,7R)-1) and octanedioyl-bis(Tyr-Arg-Leu-Arg-Tyr-amide) (2) as well as the pentapeptide Ac-Tyr-Arg-Leu-Arg-Tyr-amide (3) were previously described as neuropeptide Y Y4 receptor (Y4R) partial agonists. Here, we report on a series of analogues of (2R,7R)-1 and 2 in which Arg2, Leu3, or Arg4 were replaced by the respective aza-amino acids. The replacement of Arg2 in 3 with a carbamoylated arginine building block and the extension of the N-terminus by an additional arginine led to the high-affinity hexapeptide Ac-Arg-Tyr-Nω-[(4-aminobutyl)aminocarbonyl]Arg-Leu-Arg-Tyr-amide (35), which was used as a precursor for a d-amino acid scan. The target compounds were investigated for Y4R functional activity in assays with complementary readouts: aequorin Ca2+ and ß-arrestin 1 or ß-arrestin 2 assays. In contrast to the parent compounds, which are Y4R agonists, several ligands were able to suppress the effect elicited by the endogenous ligand pancreatic polypeptide and therefore represent a novel class of peptide Y4R antagonists.

4.
J Med Chem ; 59(13): 6045-58, 2016 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-27223253

RESUMEN

The diastereomeric mixture of d/l-2,7-diaminooctanedioyl-bis(YRLRY-NH2) (BVD-74D, 2) was described in the literature as a high affinity Y4 receptor agonist. Here we report on the synthesis and pharmacological characterization of the pure diastereomers (2R,7R)- and (2S,7S)-2 and a series of homo- and heterodimeric analogues in which octanedioic acid was used as an achiral linker. To investigate the role of the Arg residues, one or two arginines were replaced by Ala. Moreover, N(ω)-(6-aminohexylaminocarbonyl)Arg was introduced as an arginine replacement (17). (2R,7R)-2 was superior to (2S,7S)-2 in binding and functional cellular assays and equipotent with 17. [(3)H]Propionylation of one amino group in the linker of (2R,7R)-2 or at the primary amino group in 17 resulted in high affinity Y4R radioligands ([(3)H]-(2R,7R)-10, [(3)H]18) with subnanomolar Kd values.


Asunto(s)
Polipéptido Pancreático/química , Polipéptido Pancreático/farmacología , Precursores de Proteínas/química , Precursores de Proteínas/farmacología , Receptores de Neuropéptido Y/agonistas , Secuencia de Aminoácidos , Animales , Células CHO , Línea Celular Tumoral , Cricetulus , Células HEK293 , Humanos , Polipéptido Pancreático/síntesis química , Precursores de Proteínas/síntesis química , Receptores de Neuropéptido Y/metabolismo , Estereoisomerismo
5.
J Med Chem ; 59(5): 1925-45, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26824643

RESUMEN

Derivatization of biologically active peptides by conjugation with fluorophores or radionuclide-bearing moieties is an effective and commonly used approach to prepare molecular tools and diagnostic agents. Whereas lysine, cysteine, and N-terminal amino acids have been mostly used for peptide conjugation, we describe a new, widely applicable approach to peptide conjugation based on the nonclassical bioisosteric replacement of the guanidine group in arginine by a functionalized carbamoylguanidine moiety. Four arginine-containing peptide receptor ligands (angiotensin II, neurotensin(8-13), an analogue of the C-terminal pentapeptide of neuropeptide Y, and a neuropeptide FF analogue) were subject of this proof-of-concept study. The N(ω)-carbamoylated arginines, bearing spacers with a terminal amino group, were incorporated into the peptides by standard Fmoc solid phase peptide synthesis. The synthesized chemically stable peptide derivatives showed high receptor affinities with Ki values in the low nanomolar range, even when bulky fluorophores had been attached. Two new tritiated tracers for angiotensin and neurotensin receptors are described.


Asunto(s)
Angiotensina II/farmacología , Arginina/análogos & derivados , Neuropéptido Y/farmacología , Neurotensina/farmacología , Oligopéptidos/farmacología , Fragmentos de Péptidos/farmacología , Receptores de Angiotensina/metabolismo , Receptores de Neuropéptido/metabolismo , Receptores de Neurotensina/metabolismo , Angiotensina II/química , Arginina/química , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Ligandos , Estructura Molecular , Neuropéptido Y/química , Neurotensina/química , Oligopéptidos/química , Fragmentos de Péptidos/química , Receptores de Neuropéptido/agonistas , Receptores de Neurotensina/antagonistas & inhibidores , Relación Estructura-Actividad
6.
J Clin Endocrinol Metab ; 101(2): 353-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26678657

RESUMEN

CONTEXT: Germline mutations in the phosphatase and tensin homolog (PTEN) tumor suppressor gene are found in the majority of patients with Cowden syndrome (CS), who have an increased risk of breast, thyroid, and endometrial cancer. According to our current understanding of genetic changes in the PTEN gene and the resultant phenotypic features of CS, pancreatic neuroendocrine tumors (NETs) are not considered part of the clinical spectrum of CS. CASE DESCRIPTION: We report a unique case of an advanced NET of the pancreas in a patient with CS. The germline DNA sequencing confirmed the clinical diagnosis of CS and revealed a PTEN mutation c.697C→T (p.R233*) causing a premature stop codon in exon 7. The tumor DNA sequencing showed no loss of heterozygosity or any copy number changes and no other deleterious genetic alterations, including those commonly mutated in sporadic pancreatic NETs: MEN1, ATRX, DAXX, TP53, and genes involved in the mammalian target of rapamycin pathway. In addition, the high-throughput transcriptome analyzed by RNA-seq did not reveal any missed genetic alterations, aberrant splicing variants, gene fusions, or gene expression alterations. The immunohistochemical staining of the tumor for PTEN revealed an abnormal, uniformly strong cytoplasmic staining of tumor cells with virtually absent nuclear staining. CONCLUSION: The results from genetic testing and histopathological techniques used to confirm CS diagnosis and characterize this unusual tumor tempted us to believe that in this case, the pancreatic NET was not a sporadic malignancy that occurred by coincidence, but rather represented a new entity in the spectrum of malignancies associated with CS.


Asunto(s)
Síndrome de Hamartoma Múltiple/diagnóstico , Tumores Neuroendocrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , ADN/genética , Mutación de Línea Germinal/genética , Síndrome de Hamartoma Múltiple/genética , Síndrome de Hamartoma Múltiple/patología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/patología , Fosfohidrolasa PTEN/genética , Páncreas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Linaje , ARN Neoplásico/genética
7.
Eur J Cancer ; 51(5): 653-67, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25638778

RESUMEN

BACKGROUND: Patient numbers requiring long-term melanoma surveillance are constantly rising. Surveillance is costly and guideline recommendations vary substantially. METHODS: In this German nationwide study, information on surveillance and treatment of patients diagnosed with melanoma and melanoma in situ (MMis) between April and June 2008 was prospectively collected over four years. Additionally, patient self-report questionnaires were evaluated to assess anxiety, depression, health-related quality of life, socio-demographic information and use of disease specific health information sources at year 4 after primary diagnosis. RESULTS: Complete data was available for 668 patients from 67 centres, of whom 96.0% were in regular melanoma surveillance. In year 3-4 of surveillance, only 55.6% of locoregionary metastases were detected during surveillance visits. Only 33.3% were self-detected by the patient even though 69.4% were documented as being clinically visible or palpable. Costs of 4year surveillance of 550 patients without tumour recurrence (stage I-IIC and MMis) accumulated to 228,155.75 €. Guideline-adherence for follow-up frequency, lymph node ultrasound, S100 serum level tests and diagnostic imaging recommendations was approximately 60% in year 3-4 of surveillance. Multivariate regression analysis showed that certain patient/tumour characteristics and regional differences were significantly associated with guideline deviations. The percentage of patients who exceeded published cut-off scores indicating clinically relevant symptoms of anxiety and depression were significantly increased. Patients frequently reported lack of psychosocial support and education but ascribed great importance to these. CONCLUSIONS: We recommend further reduction of melanoma follow-up in low-risk melanoma patients and improvement of psycho-social support and patient education for all melanoma patients.


Asunto(s)
Cuidados a Largo Plazo , Oncología Médica , Melanoma/diagnóstico , Melanoma/terapia , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/terapia , Adulto , Anciano , Progresión de la Enfermedad , Detección Precoz del Cáncer , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Adhesión a Directriz , Conocimientos, Actitudes y Práctica en Salud , Disparidades en Atención de Salud , Humanos , Cuidados a Largo Plazo/normas , Estudios Longitudinales , Masculino , Oncología Médica/normas , Melanoma/epidemiología , Melanoma/psicología , Melanoma/secundario , Persona de Mediana Edad , Educación del Paciente como Asunto , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Valor Predictivo de las Pruebas , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Autoexamen , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/psicología , Apoyo Social , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
9.
Ann Oncol ; 26(3): 573-82, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25524477

RESUMEN

BACKGROUND: Kinase inhibitors targeting the BRAF V600 mutation have become standard in the treatment of metastatic melanoma. Albeit in wide clinical use, the patterns associated with therapy outcome are not fully elucidated. The present study was aimed to identify predictive factors of therapy response and survival under the BRAF inhibitor vemurafenib. PATIENTS AND METHODS: This multicenter retrospective study analyzed patient, tumor, and pretreatment characteristics collected in BRAF V600-mutated stage IV melanoma patients before single-agent therapy with the BRAF inhibitor vemurafenib. RESULTS: A total of 300 patients from 14 centers were included into this study with a median follow-up time of 13.0 months. Median progression-free survival (PFS) was 5.1 months; median overall survival (OS) was 7.6 months. Best response under vemurafenib was associated with serum lactate dehydrogenase (LDH; ≤ versus >upper normal limit; P = 0.0000001), Eastern Cooperative Oncology Group (ECOG) overall performance status (OPS) (0 versus ≥ 1; P = 0.00089), and BRAF mutation subtype (V600E versus V600K; P = 0.016). Multivariate analysis identified ECOG OPS ≥ 1 [hazard ratio (HR) = 1.88; P = 0.00005], immunotherapy pretreatment (HR = 0.53; P = 0.0067), elevated serum LDH (HR = 1.45; P = 0.012), age >55 years (HR = 0.72; P = 0.019), and chemotherapy pretreatment (HR = 1.39; P = 0.036) as independent predictors of PFS. For OS, elevated serum LDH (HR = 1.99; P = 0.00012), ECOG OPS ≥ 1 (HR = 1.90; P = 0.00063), age >55 years (HR = 0.65; P = 0.011), kinase inhibitor pretreatment (HR = 1.86; P = 0.014), immunotherapy pretreatment (HR = 0.57; P = 0.025), chemotherapy pretreatment (HR = 2.17; P = 0.039), and male gender (HR = 0.70; 95% confidence interval 0.50-0.98; P = 0.039) were found as predictors. CONCLUSION: Our data demonstrate that the type of pretreatment strongly influences the outcome of vemurafenib therapy, with a precedent immunotherapy showing a positive, and a prior chemotherapy and kinase inhibitors showing a negative impact on survival, respectively. Moreover, we show that the patient's OPS, serum LDH, age, and gender independently impact vemurafenib therapy outcome. These findings should be taken into account for the future design of therapy sequencing in BRAF V600 mutation-positive melanoma patients.


Asunto(s)
Indoles/administración & dosificación , Melanoma/diagnóstico , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/tratamiento farmacológico , Sulfonamidas/administración & dosificación , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Vemurafenib
10.
Hautarzt ; 64(7): 512-5, 2013 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-23595891

RESUMEN

Dermatofibrosarcoma protuberans (DFSP) is a rare dermal tumor of intermediate malignancy with a locally aggressive growth behavior with a high rate of recurrence. Wide local excision with histographic margin control as well as regular follow-ups including clinical as well as ultrasound examination are crucial to detect local recurrence or metastasis. Ultrasound imaging can not only identify recurrences but also asses their extent. We report on a patient with a relapse of fibrosarcomatous DFSP, which could be demonstrated by ultrasound imaging.


Asunto(s)
Dermatofibrosarcoma/diagnóstico por imagen , Dermatofibrosarcoma/patología , Fibrosarcoma/diagnóstico por imagen , Fibrosarcoma/cirugía , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/cirugía , Ultrasonografía/métodos , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Recurrencia , Resultado del Tratamiento
11.
Eur J Anaesthesiol ; 30(8): 492-500, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23344121

RESUMEN

CONTEXT: Cardiopulmonary bypass (CPB) is a commonly used technique in cardiac surgery but is associated with acute, transient, renal dysfunction that has a negative impact on long-term survival. OBJECTIVE: To unravel the molecular pathogenesis of renal injury following CPB. DESIGN: To obtain insight into the pathogenesis of renal dysfunction following CPB, we performed a microarray analysis of renal gene expression in the rat. SETTING: University Medical Centre Groningen. INTERVENTION: Rats underwent CPB or a sham procedure for 60 min and were sacrificed at 60 min, 1 and 5 days after the procedure. MAIN OUTCOME MEASURES: Renal gene expression profile as determined by microarray analysis. RESULTS: Expression of 420 genes was significantly altered in CPB compared to the sham procedure, and in 407 genes, this was evident in the acute phase (60 min) following CPB. Gene ontology analysis revealed 28 of these genes were involved in inflammatory responses, with high expression of genes downstream of mitogen-activated protein-kinase (MAP-kinase) signalling pathways. Potent inducers identified are from the interleukin-6 cytokine family that consists of interleukin-6 and oncostatin M (OSM), which signal through the gp130-cytokine receptor complex. The plasma concentration of interleukin-6 was hugely increased by CPB as measured by ELISA. Expression of genes downstream of these signalling pathways that lead to production of chemokines, adhesion molecules and molecules involved in coagulative pathways, was upregulated. CONCLUSION: CPB induces an acute and local inflammatory response in the kidney, which might contribute to renal injury. The signalling pathways involved identified by gene expression analysis may represent pharmacological targets to limit renal injury following CPB.


Asunto(s)
Puente Cardiopulmonar/efectos adversos , Inflamación/patología , Riñón/metabolismo , Transcriptoma , Animales , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Riñón/lesiones , Riñón/fisiopatología , Sistema de Señalización de MAP Quinasas , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Wistar , Transducción de Señal , Factores de Tiempo
12.
J Thorac Cardiovasc Surg ; 122(3): 518-23, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11547304

RESUMEN

OBJECTIVE: Pulmonary arteriovenous malformations may cause progressive cyanosis after cavopulmonary anastomosis and may develop as a result of abnormal angiogenesis. We used immunohistochemistry to determine whether angiogenic proteins are increased in the lungs of children after cavopulmonary anastomosis. METHODS: Lung specimens were obtained from 13 children after cavopulmonary anastomosis and from 6 control subjects. Specimens were stained with antibodies against vascular endothelial growth factor and its receptor (flk-1/KDR), basic fibroblast growth factor, alpha-smooth muscle actin, CD31, collagen IV, fibronectin, and proliferating cell nuclear antigen. Staining was graded on a scale of 0 to 3. Vessels positive for proliferating cell nuclear antigen were counted in 10 fields per specimen, and the results were averaged. RESULTS: After cavopulmonary anastomosis, patients demonstrated increased staining for vascular endothelial growth factor (P =.03) and its receptor (P =.03) and decreased staining for CD31 (P =.004). Proliferating cell nuclear antigen staining in patients was equivalent to that for control subjects (P =.9). CONCLUSIONS: Lung biopsy specimens from children after cavopulmonary anastomosis demonstrate increased expression of vascular endothelial growth factor and its receptor. These data confirm earlier findings that blood vessels forming after cavopulmonary anastomosis may have reduced intercellular junctions (decreased CD31 staining). Despite the increased numbers of pulmonary vessels that are present in these patients, these vessels are not highly proliferative (proliferating cell nuclear antigen staining equivalent to that of control subjects). These results suggest that vascular endothelial growth factor may be a mediator of angiogenesis in the lungs of children after cavopulmonary anastomosis; however, other factors, such as vascular dilation and remodeling, may also be important.


Asunto(s)
Malformaciones Arteriovenosas/etiología , Malformaciones Arteriovenosas/patología , Cianosis/etiología , Cianosis/patología , Factores de Crecimiento Endotelial/análisis , Puente Cardíaco Derecho/efectos adversos , Linfocinas/análisis , Neovascularización Patológica/etiología , Neovascularización Patológica/patología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Arteria Pulmonar/anomalías , Proteínas Tirosina Quinasas Receptoras/análisis , Receptores de Factores de Crecimiento/análisis , Adolescente , Malformaciones Arteriovenosas/cirugía , Biopsia , Estudios de Casos y Controles , Niño , Preescolar , Progresión de la Enfermedad , Procedimiento de Fontan , Humanos , Inmunohistoquímica , Lactante , Neovascularización Patológica/cirugía , Antígeno Nuclear de Célula en Proliferación/análisis , Receptores de Factores de Crecimiento Endotelial Vascular , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
13.
Biochim Biophys Acta ; 1540(2): 154-65, 2001 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-11513977

RESUMEN

Homocystinuria is a metabolic disorder associated with an increased incidence of vascular disease. Here, we analyzed the effects of homocysteine on endothelial cell activation that is a prerequisite for the recruitment of leukocytes to sites of evolving atherosclerotic plaques. Exposure of human umbilical vein endothelial cells to homocysteine alone did not modulate expression of the adhesion molecules E-selectin, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, and the chemokines monocyte chemotactic protein-1 and interleukin-8. In contrast, tumor necrosis factor (TNF)-induced upregulation of these molecules was almost completely inhibited by homocysteine, but not by related thiol amino acids. Using electrophoretic mobility shift and reporter gene assays, the inhibitory effect of homocysteine could be attributed to inhibition of DNA binding and transcriptional activity of NF-kappa B. TNF-induced phosphorylation and degradation of I kappa B-alpha, however, were not affected. Neither was NF-kappa B-independent activation of endothelial cells by interferon-gamma influenced by homocysteine. In summary, our data indicate that homocysteine alters the response to injury of endothelial cells which may have fundamental impacts on mechanisms of leukocyte recruitment to sites of inflammation. Our findings might refer to a novel pathway by which homocysteine is involved in vascular disorders associated with homocystinuria.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Homocisteína/farmacología , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Células Cultivadas , Endotelio Vascular/metabolismo , Humanos , Interferón gamma , Transducción de Señal
14.
Blood ; 97(1): 46-55, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11133741

RESUMEN

The cytokine-induced C-C chemokine monocyte chemoattractant protein-1 (MCP-1) is an important regulator of leukocyte recruitment to sites of inflammatory challenge. Here, it is demonstrated that the widely distributed contact hapten NiCl(2), like tumor necrosis factor alpha (TNFalpha), induces monocyte-chemoattractant activity in primary human endothelial cells via induction of MCP-1. NiCl(2) rapidly activated mitogen-activated protein (MAP) kinase p38, and inhibition of p38 partially blocked NiCl(2)-induced MCP-1 messenger RNA and protein expression. Both NiCl(2)- and TNFalpha-induced MCP-1 synthesis was sensitive to D609, an inhibitor of phosphatidylcholine-dependent phospholipase C (PC-PLC). NiCl(2)-induced MCP-1 synthesis required activation of NF-kappaB since mutation of NF-kappaB-binding sites in the promoter resulted in complete loss of inducible promoter activity. Consistent with that finding, stimulation with NiCl(2) or TNFalpha activated IkappaB kinase-beta (IKKbeta), and transient transfection of dominant-negative IKKbeta strongly inhibited NiCl(2)- and TNFalpha-induced MCP-1 expression. However, D609 and the specific p38 inhibitor SB202190 did not affect NiCl(2)- and TNFalpha-induced IKKbeta activation, NF-kappaB DNA-binding activity, or transcriptional activity of a Gal4p65 fusion protein. This indicates that p38- and PC-PLC-dependent pathways directly regulate the transcriptional activity of NF-kappaB factors in the transcriptional complex. Consistent with that, inhibition of p38 blocked enhanced transcriptional activity induced by the transcriptional coactivator p300. Thus, it was concluded that at least 3 independent pathways regulate MCP-1 expression in endothelial cells. Its induction requires activation of the IKKbeta/IkappaBalpha/NF-kappaB signaling pathway, resulting in nuclear accumulation of p65 and subsequent recruitment of cofactors. Proper assembly and activity of this transcriptional complex is further modulated by the p38 MAP kinase cascade and a PC-PLC-dependent pathway.


Asunto(s)
Quimiocina CCL2/biosíntesis , Quimiocina CCL2/genética , Endotelio Vascular/metabolismo , FN-kappa B/farmacología , Endotelio Vascular/citología , Endotelio Vascular/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Haptenos , Humanos , Proteínas Quinasas Activadas por Mitógenos/fisiología , Níquel/farmacología , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/efectos de los fármacos , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Transducción de Señal/fisiología , Transactivadores/antagonistas & inhibidores , Transactivadores/efectos de los fármacos , Transactivadores/metabolismo , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Fosfolipasas de Tipo C/fisiología , Venas Umbilicales/citología , Proteínas Quinasas p38 Activadas por Mitógenos
15.
Ann Thorac Surg ; 68(2): 521-5; discussion 525-6, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10475422

RESUMEN

BACKGROUND: Aortic valve replacement (AVR) in children is now more commonly performed with human tissue valves. METHODS: The results of 100 consecutive pediatric AVRs (50 mechanical, 50 human) were reviewed. RESULTS: There were five perioperative deaths in the mechanical group and one in the human group (p = 0.2). Late complications in the mechanical group included 4 late deaths, 2 cases of endocarditis, 3 thromboembolic complications, and 10 reoperations on the aortic valve. In the human group, there were no late deaths, 2 reoperations for allograft aortic valve deterioration (both in Marfan's patients), and 1 reoperation for allograft pulmonary valve stenosis. Four-year actuarial survival was 83% in the mechanical group and 98% in the human group (p = 0.02). Four-year actuarial survival free of all valve-related complications was 61% in the mechanical group and 88% in the human group (p = 0.008). CONCLUSIONS: Human valves in children requiring AVR provide superior intermediate-term survival and freedom from valve-related complications compared to mechanical valves. Marfan's syndrome may represent a rare remaining contraindication for human AVR in children.


Asunto(s)
Válvula Aórtica/cirugía , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas , Complicaciones Posoperatorias/cirugía , Análisis Actuarial , Adolescente , Adulto , Válvula Aórtica/anomalías , Válvula Aórtica/trasplante , Niño , Preescolar , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/cirugía , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/mortalidad , Falla de Prótesis , Reoperación , Tasa de Supervivencia , Trasplante Autólogo , Trasplante Homólogo
16.
Blood ; 93(3): 857-65, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9920834

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1), a member of the C-C subfamily of chemokines, is important for the local recruitment of leukocytes to sites of inflammatory challenge. Here, we investigated endothelial signaling pathways involving members of the mitogen-activated protein (MAP) kinase superfamily and studied their role for MCP-1 expression in endothelium. We show that tumor necrosis factor-alpha (TNF-alpha), a potent inflammatory activator of endothelium, leads to activation of MAP kinases ERK, p38, and JNK in human umbilical vein endothelial cells (HUVEC). Contribution of MAP kinase pathways to TNF-alpha-induced synthesis of endothelial MCP-1 was then studied by pharmacologic inhibition and transient expression of dominant negative or constitutively active kinase mutants using flow cytometry, Northern blot, and luciferase reporter gene assays. Inhibition of Raf/MEK/ERK or SEK/JNK pathways had no significant effect on MCP-1 levels, whereas blocking the MKK6/p38 pathway by p38 inhibitors SB203580 or SB202190 or by a dominant negative mutant of MKK6, the upstream activator of p38, strongly inhibited TNF-alpha-induced expression of MCP-1. Consistent with that finding, expression of wild-type or constitutively active MKK6 significantly enhanced the effect of limiting TNF-alpha concentrations on MCP-1 synthesis. These data suggest a crucial role for the MKK6/p38 stress kinase cascade in TNF-alpha-mediated endothelial MCP-1 expression.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Quimiocina CCL2/biosíntesis , Endotelio Vascular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos , Transducción de Señal/fisiología , Estrés Fisiológico/fisiopatología , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/antagonistas & inhibidores , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Células Cultivadas , Quimiocina CCL2/genética , Endotelio Vascular/citología , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Humanos , Imidazoles/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos , MAP Quinasa Quinasa 6 , Proteína Quinasa 3 Activada por Mitógenos , Familia de Multigenes , Piridinas/farmacología , ARN Mensajero/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos
17.
J Biol Chem ; 273(4): 1917-22, 1998 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-9442025

RESUMEN

Cell response to a wide variety of extracellular signals is mediated by either mitogenic activation of the Raf/MEK/ERK kinase cascade or stress-induced activation of the mitogen-activated protein kinase (MAPK) family members c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) or p38. We have examined communications between these stress- and mitogen-induced signaling pathways. We show here that the stress cascade activator arsenite activates extracellular signal-regulated kinase (ERK) in addition to p38 albeit with different kinetics. Whereas p38 is an early response kinase, ERK activation occurs with delayed time kinetics at 2-4 h. We observed activation of ERK upon arsenite treatment in many different cell lines. ERK activation is strongly enhanced by overexpression of p38 and mitogen-activated protein kinase kinase 6 (MKK6) but is blocked by dominant negative kinase versions of p38 and MKK6 or the specific p38 inhibitor SB203580. Arsenite-induced ERK activation is mediated by Ras, Raf, and MEK but appears to be independent of de novo protein synthesis. These data provide the first evidence for a p38 dependent activation of the mitogenic kinase cascade in stress-stimulated cells.


Asunto(s)
Arsenitos/farmacología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos , Proteínas Quinasas , Endotelio Vascular/citología , Endotelio Vascular/enzimología , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Células HL-60 , Humanos , Imidazoles/farmacología , Péptidos y Proteínas de Señalización Intracelular , MAP Quinasa Quinasa 6 , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-raf/metabolismo , Piridinas/farmacología , Regulación hacia Arriba/efectos de los fármacos , Proteínas ras/metabolismo
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