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1.
Front Endocrinol (Lausanne) ; 15: 1336128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650714

RESUMO

Purpose: Surgery is the only way to cure pheochromocytoma; however, postoperative hemodynamic instability is one of the main causes of serious complications and even death. This study's findings provide some guidance for improved clinical management. Patients and methods: This study was to investigate the factors leading to postoperative hemodynamic instability in the postoperative pathology indicated pheochromocytoma from May 2016 to May 2022. They were divided into two groups according to whether vasoactive drugs were used for a median number of days or more postoperatively. The factors affecting the postoperative hemodynamics in the perioperative period (preoperative, intraoperative, and postoperative) were then evaluated. Results: The median number of days requiring vasoactive drug support postoperatively was three in 234 patients, while 118 (50.4%) patients required vasoactive drug support for three days or more postoperatively. The results of the multivariate analysis indicated more preoperative colloid use (odds ratio [OR]=1.834, confidence interval [CI]:1.265-2.659, P=0.001), intraoperative use of vasoactive drug (OR=4.174, CI:1.882-9.258, P<0.001), and more postoperative crystalloid solution input per unit of body weight per day (ml/kg/d) (OR=1.087, CI:1.062-1.112, P<0.001) were risk factors for predicting postoperative hemodynamic instability. The optimal cutoff point of postoperative crystalloid use were 42.37 ml/kg/d. Conclusion: Hemodynamic instability is a key issue for consideration in the perioperative period of pheochromocytoma. The amount of preoperative colloid use, the need for intraoperative vasoactive drugs, and postoperative crystalloid solution are risk factors for predicting postoperative hemodynamic instability (registration number: ChiCT2300071166).


Assuntos
Neoplasias das Glândulas Suprarrenais , Hemodinâmica , Feocromocitoma , Complicações Pós-Operatórias , Feocromocitoma/cirurgia , Feocromocitoma/fisiopatologia , Humanos , Feminino , Masculino , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Hemodinâmica/fisiologia , Pessoa de Meia-Idade , Adulto , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos de Coortes , Adrenalectomia/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Idoso , Vasoconstritores/uso terapêutico , Soluções Cristaloides/administração & dosagem
2.
J Hazard Mater ; 436: 129129, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35584584

RESUMO

Superhydrophilic/underwater superoleophobic coatings that effectively prevent viscous oil contamination have been of considerable interest for the great potential in oil spill remediation and oilfield wastewater treatment. In the present work, a protonated cross-linkable nanocomposite coating with robust underwater superoleophobicity and intensified hydration capability is proposed through the synthesis of active polymeric nanocomplex (PNC), cross-linking reaction between PNC and hydrophilic chitosan (CS), and final protonation to further improve water affinity. Benefiting from the hierarchical structure and strong hydration capability induced by electrostatic interactions and hydrogen bondings, the nanocomposite coating coated textile exhibits excellent superhydrophilicity (within 0.28 s with water contact angle reaching 0°), underwater superoleophobicity (underwater crude oil contact angle at 160°), and ultralow oil adhesion even to highly viscous silicone oil. Moreover, the nanocomposite coating presents a robust chemical resistance, mechanical tolerance, and storage stability. Simultaneously, the nanocomposite coating adapts well to various porous substrates (e.g., stainless steel mesh and Ni sponge) with great anti-oil-fouling and self-cleaning performances. Importantly, the coating coated textile is successfully applied in crude oil/water separation with excellent efficiency and repeatability. The findings conceivably stand out as a new methodology to fabricate superhydrophilic/underwater superoleophobic materials with outstanding anti-viscous oil-fouling property for practically treating oily wastewater.

3.
Exp Ther Med ; 22(6): 1350, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34659496

RESUMO

The present study aimed to investigate the effect of a new method of abdominal skin care on patients with ankylosing spondylitis (AS) undergoing orthopedic surgery. A total of 90 patients with AS and thoracolumbar kyphosis undergoing orthopedic surgery were randomly divided into two groups. Patients in the control group received routine care while those in experimental group received the following new treatment regimen: i) Vaseline cream was applied to the abdominal skin for 3-5 min every 6 h; ii) preoperative stretch exercises were encouraged and iii) 24 h after surgery, the patient was placed in a lateral decubitus position. The difference in abdominal pain levels and the size of tension blisters was the compared between the two groups. There was no difference in age, gender, disease course and kyphosis angle between two groups (P>0.05). Compared with the patients in the control group, those in test group experienced milder pain when evaluated by visual analogue score at 6, 18 and 30 h after surgery (3.6±1.2 vs. 4.5±1.8; 4.4±2.3 vs. 6.1±2.7; 4.1±2.1 vs. 4.1±2.1, P<0.05). Moreover, tension vesicles in the abdominal skin were significantly smaller in the treatment group than the control group (P<0.05). Optimal nursing may be the key to the reduction of the level of pain and occurrence of tension vacuoles in the abdominal skin.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32974300

RESUMO

Tuberculosis (TB) is one of the most potent infectious diseases in the world, causing more deaths than any other single infectious agent. TB infection is caused by inhalation of Mycobacterium tuberculosis (Mtb) and subsequent phagocytosis and migration into the lung tissue by innate immune cells (e.g., alveolar macrophages, neutrophils, and dendritic cells), resulting in the formation of a fused mass of immune cells known as the granuloma. Considered the pathological hallmark of TB, the granuloma is a complex microenvironment that is crucial for pathogen containment as well as pathogen survival. Disruption of the delicate granuloma microenvironment via numerous stimuli, such as variations in cytokine secretions, nutrient availability, and the makeup of immune cell population, can lead to an active infection. Herein, we present a novel in vitro model to examine the soluble factor signaling between a mycobacterial infection and its surrounding environment. Adapting a newly developed suspended microfluidic platform, known as Stacks, we established a modular microscale infection model containing human immune cells and a model mycobacterial strain that can easily integrate with different microenvironmental cues through simple spatial and temporal "stacking" of each module of the platform. We validate the establishment of suspended microscale (4 µL) infection cultures that secrete increased levels of proinflammatory factors IL-6, VEGF, and TNFα upon infection and form 3D aggregates (granuloma model) encapsulating the mycobacteria. As a proof of concept to demonstrate the capability of our platform to examine soluble factor signaling, we cocultured an in vitro angiogenesis model with the granuloma model and quantified morphology changes in endothelial structures as a result of culture conditions (P < 0.05 when comparing infected vs. uninfected coculture systems). We envision our modular in vitro granuloma model can be further expanded and adapted for studies focusing on the complex interplay between granulomatous structures and their surrounding microenvironment, as well as a complementary tool to augment in vivo signaling and mechanistic studies.

5.
Lab Chip ; 20(1): 107-119, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31712791

RESUMO

Open microfluidic cell culture systems are powerful tools for interrogating biological mechanisms. We have previously presented a microscale cell culture system, based on spontaneous capillary flow of biocompatible hydrogels, that is integrated into a standard cell culture well plate, with flexible cell compartment geometries and easy pipet access. Here, we present two new injection molded open microfluidic devices that also easily insert into standard cell culture well plates and standard culture workflows, allowing seamless adoption by biomedical researchers. These platforms allow culture and study of soluble factor communication among multiple cell types, and the microscale dimensions are well-suited for rare primary cells. Unique advances include optimized evaporation control within the well, manufacture with reproducible and cost-effective rapid injection molding, and compatibility with sample preparation workflows for high resolution microscopy (following well-established coverslip mounting procedures). In this work, we present several use cases that highlight the usability and widespread utility of our platform including culture of limited primary testis cells from surgical patients, microscopy readouts including immunocytochemistry and single molecule fluorescence in situ hybridization (smFISH), and coculture to study interactions between adipocytes and prostate cancer cells.


Assuntos
Dispositivos Lab-On-A-Chip , Testículo/citologia , Sobrevivência Celular , Células Cultivadas , Técnicas de Cocultura , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino
6.
ACS Appl Mater Interfaces ; 10(4): 4213-4221, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29323869

RESUMO

Superhydrophobic surfaces with tunable adhesion from lotus-leaf to rose-petal states have generated much attention for their potential applications in self-cleaning, anti-icing, oil-water separation, microdroplet transportation, and microfluidic devices. Herein we report a facile magnetic-field-manipulation strategy to fabricate dual-functional superhydrophobic textiles with asymmetric roll-down/pinned states on the two surfaces of the textile simultaneously. Upon exposure to a static magnetic field, fluoroalkylsilane-modified iron oxide (F-Fe3O4) nanoparticles in polydimethylsiloxane (PDMS) moved along the magnetic field to construct discrepant hierarchical structures and roughnesses on the two sides of the textile. The positive surface (closer to the magnet, or P-surface) showed a water contact angle up to 165°, and the opposite surface (or O-surface) had a water contact angle of 152.5°. The P-surface where water droplets easily slid off with a sliding angle of 7.5° appeared in the "roll-down" state as Cassie mode, while the O-surface was in the "pinned" state as Wenzel mode, where water droplets firmly adhered even at vertical (90°) and inverted (180°) angles. The surface morphology and wetting mode were adjustable by varying the ratios of F-Fe3O4 nanoparticles and PDMS. By taking advantage of the asymmetric adhesion behaviors, the as-fabricated superhydrophobic textile was successfully applied in no-loss microdroplet transportation and oil-water separation. Our method is simple and cost-effective. The fabricated textile has the characteristics of superhydrophobicity, magnetic responsiveness, excellent chemical stability, adjustable surface morphology, and controllable adhesion. Our findings conceivably stand out as a new tool to fabricate functional superhydrophobic materials with asymmetric surface properties for various potential applications.

7.
ACS Appl Mater Interfaces ; 9(33): 28089-28099, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28758736

RESUMO

Large-scale fabrication of superhydrophobic surfaces with excellent durability by simple techniques has been of considerable interest for its urgent practical application in oil-water separation in recent years. Herein, we proposed a facile vapor-liquid sol-gel approach to fabricating highly durable and robust superhydrophobic polydimethylsiloxane@silica surfaces on the cross-structure polyester textiles. Scanning electron microscopy and Fourier transform infrared spectroscopy demonstrated that the silica generated from the hydrolysis-condensation of tetraethyl orthosilicate (TEOS) gradually aggregated at microscale driven by the extreme nonpolar dihydroxyl-terminated polydimethylsiloxane (PDMS(OH)). This led to construction of hierarchical roughness and micronano structures of the superhydrophobic textile surface. The as-fabricated superhydrophobic textile possessed outstanding durability in deionized water, various solvents, strong acid/base solutions, and boiling/ice water. Remarkably, the polyester textile still retained great water repellency and even after ultrasonic treatment for 18 h, 96 laundering cycles, and 600 abrasion cycles, exhibiting excellent mechanical robustness. Importantly, the superhydrophobic polyester textile was further applied for oil-water separation as absorption materials and/or filter pipes, presenting high separation efficiency and great reusability. Our method to construct superhydrophobic textiles is simple but highly efficient; no special equipment, chemicals, or atmosphere is required. Additionally, no fluorinated slianes and organic solvents are involved, which is very beneficial for environment safety and protection. Our findings conceivably stand out as a new tool to fabricate organic-inorganic superhydrophobic surfaces with strong durability and robustness for practical applications in oil spill accidents and industrial sewage emission.

8.
ACS Appl Mater Interfaces ; 9(3): 3131-3141, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28032982

RESUMO

Functional surfaces for reversibly switchable wettability and oil-water separation have attracted much interest with pushing forward an immense influence on fundamental research and industrial application in recent years. This article proposed a facile method to fabricate superhydrophobic surfaces on steel substrates via electroless replacement deposition of copper sulfate (CuSO4) and UV curing of vinyl-terminated polydimethylsiloxane (PDMS). PDMS-based superhydrophobic surfaces exhibited water contact angle (WCA) close to 160° and water sliding angle (WSA) lower than 5°, preserving outstanding chemical stability that maintained superhydrophobicity immersing in different aqueous solutions with pH values from 1 to 13 for 12 h. Interestingly, the superhydrophobic surface could dramatically switch to the superhydrophilic state under UV irradiation and then gradually recover to the highly hydrophobic state with WCA at 140° after dark storage. The underlying mechanism was also investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the PDMS-based steel mesh possessed high separation efficiency and excellent reusability in oil-water separation. Our studies provide a simple, fast, and economical fabrication method for wettability-transformable superhydrophobic surfaces and have the potential applications in microfluidics, the biomedical field, and oil spill cleanup.

9.
Eur Spine J ; 25(8): 2596-604, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27146808

RESUMO

PURPOSE: Chin-brow vertical angle (CBVA) is very important in correction of thoracolumbar kyphotic deformity in ankylosing spondylitis (AS), especially for the patients with cervical ankylosis. In previous study, Suk et al. stated that the patients with CBVA between -10° and 10° had better horizontal gaze. Unfortunately, in our clinical practice, we found the patients with CBVA between -10° and 10° after surgery usually complained of difficulty in cooking, cleaning, desk working and the like, although they had excellent horizontal gaze. In other words, for the patients with cervical ankylosis, good horizontal gaze existed together with poor downward gaze. Then, which condition do the patients prefer? Is there a compromise solution that makes a better quality life possible for the patients? In this research, we studied AS patients with cervical ankylosis, aiming to investigate the optimal CBVA for deformity correction. METHODS: 25 AS thoracolumbar kyphotic patients with cervical ankylosis were studied, whose function and expectation of visual field related to life quality were assessed by questionnaire before and after surgery. Pre- and post-operative CBVA were obtained on lateral photos of the patients with free-standing posture, and 50 cases of CBVA were included, which were divided into six groups according to the angle irrespective of surgery (Group A, CBVA <0°; Group B, 0° ≤ CBVA < 10°; Group C, 10° ≤ CBVA < 20°; Group D, 20° ≤ CBVA < 30°; Group E, 30° ≤ CBVA < 40°; Group F, CBVA ≥ 40°). Kruskal-Wallis test was used to assess all the groups in terms of various items in the questionnaire, while Mann-Whitney test was used to assess every two groups. RESULTS: In overall evaluation, Group C (10°-20°) obtained the optimal expectation (p < 0.05); Group B, C and D (0°-30°) obtained better function (p < 0.05), and there was no significant difference between the 3 groups. In appearance, Group A, B and C (<20°) were better than the other groups both in function and expectation (p < 0.05), without dramatic difference among the three groups. In outdoor activities, Group A, B, C and D (<30°) were better in most of the items (p < 0.05). In indoor activities, Group C and D (10-30°) were much better (p < 0.05). CONCLUSION: AS thoracolumbar kyphotic patients with cervical ankylosis had the best satisfaction when 10° ≤ CBVA < 20°.


Assuntos
Queixo/fisiologia , Cifose , Postura/fisiologia , Espondilite Anquilosante , Adulto , Estudos de Coortes , Feminino , Humanos , Cifose/epidemiologia , Cifose/fisiopatologia , Cifose/cirurgia , Masculino , Qualidade de Vida , Espondilite Anquilosante/epidemiologia , Espondilite Anquilosante/fisiopatologia , Espondilite Anquilosante/cirurgia , Campos Visuais
10.
PLoS One ; 8(10): e76373, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24124550

RESUMO

The utilization of 3D, physiologically relevant in vitro cancer models to investigate complex interactions between tumor and stroma has been increasing. Prior work has generally focused on the cancer cells and, the role of fibroblast culture conditions on tumor-stromal cell interactions is still largely unknown. Here, we focus on the stroma by comparing functional behaviors of human mammary fibroblasts (HMFs) cultured in 2D and 3D and their effects on the invasive progression of breast cancer cells (MCF10DCIS.com). We identified increased levels of several paracrine factors from HMFs cultured in 3D conditions that drive the invasive transition. Using a microscale co-culture model with improved compartmentalization and sensitivity, we demonstrated that HMFs cultured in 3D intensify the promotion of the invasive progression through the HGF/c-Met interaction. This study highlights the importance of the 3D stromal microenvironment in the development of multiple cell type in vitro cancer models.


Assuntos
Neoplasias da Mama/metabolismo , Técnicas de Cocultura , Fibroblastos/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Fibroblastos/patologia , Fator de Crescimento de Hepatócito/biossíntese , Humanos , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/metabolismo , Técnicas Analíticas Microfluídicas/métodos , Invasividade Neoplásica , Fenótipo , Células Estromais/metabolismo , Células Estromais/patologia
11.
Anal Chem ; 85(3): 1562-70, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23327437

RESUMO

Microfluidics is emerging as a promising platform for cell culture, enabling increased microenvironment control and potential for integrated analysis compared to conventional macroculture systems such as well plates and Petri dishes. To advance the use of microfluidic devices for cell culture, it is necessary to better understand how miniaturization affects cell behavior. In particular, microfluidic devices have significantly higher surface-area-to-volume ratios than conventional platforms, resulting in lower volumes of media per cell, which can lead to cell stress. We investigated cell stress under a variety of culture conditions using three cell lines: parental HEK (human embryonic kidney) cells and transfected HEK cells that stably express wild-type (WT) and mutant (G601S) human ether-a-go-go related gene (hERG) potassium channel protein. These three cell lines provide a unique model system through which to study cell-type-specific responses in microculture because mutant hERG is known to be sensitive to environmental conditions, making its expression a particularly sensitive readout through which to compare macro- and microculture. While expression of WT-hERG was similar in microchannel and well culture, the expression of mutant G601S-hERG was reduced in microchannels. Expression of the endoplasmic reticulum (ER) stress marker immunoglobulin binding protein (BiP) was upregulated in all three cell lines in microculture. Using BiP expression, glucose consumption, and lactate accumulation as readouts we developed methods for reducing ER stress including properly increasing the frequency of media replacement, reducing cell seeding density, and adjusting the serum concentration and buffering capacity of culture medium. Indeed, increasing the buffering capacity of culture medium or frequency of media replacement partially restored the expression of the G601S-hERG in microculture. This work illuminates how biochemical properties of cells differ in macro- and microculture and suggests strategies that can be used to modify cell culture protocols for future studies involving miniaturized culture platforms.


Assuntos
Técnicas de Cultura de Células/métodos , Estresse do Retículo Endoplasmático/fisiologia , Células Epiteliais/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Estresse Mecânico , Animais , Canal de Potássio ERG1 , Células Epiteliais/química , Canais de Potássio Éter-A-Go-Go/química , Células HEK293 , Humanos , Camundongos
12.
J Biomol Screen ; 16(1): 101-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21131594

RESUMO

Evaluation of drug cardiotoxicity is essential to the safe development of novel pharmaceuticals. Assessing a compound's risk for prolongation of the surface electrocardiographic QT interval and hence risk for life-threatening arrhythmias is mandated before approval of nearly all new pharmaceuticals. QT prolongation has most commonly been associated with loss of current through hERG (human ether-a-go-go related gene) potassium ion channels due to direct block of the ion channel by drugs or occasionally by inhibition of the plasma membrane expression of the channel protein. To develop an efficient, reliable, and cost-effective hERG screening assay for detecting drug-mediated disruption of hERG membrane trafficking, the authors demonstrate the use of microfluidic-based systems to improve throughput and lower cost of current methods. They validate their microfluidics array platform in polystyrene (PS), cyclo-olefin polymer (COP), and polydimethylsiloxane (PDMS) microchannels for drug-induced disruption of hERG trafficking by culturing stably transfected HEK cells that overexpressed hERG (WT-hERG) and studying their morphology, proliferation rates, hERG protein expression, and response to drug treatment. Results show that WT-hERG cells readily proliferate in PS, COP, and PDMS microfluidic channels. The authors demonstrated that conventional Western blot analysis was possible using cell lysate extracted from a single microchannel. The Western blot analysis also provided important evidence that WT-hERG cells cultured in microchannels maintained regular (well plate-based) expression of hERG. The authors further show that experimental procedures can be streamlined by using direct in-channel immunofluorescence staining in conjunction with detection using an infrared scanner. Finally, treatment of WT-hERG cells with 5 different drugs suggests that PS (and COP) microchannels were more suitable than PDMS microchannels for drug screening applications, particularly for tests involving hydrophobic drug molecules.


Assuntos
Técnicas de Cultura de Células , Avaliação Pré-Clínica de Medicamentos/métodos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/metabolismo , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Transporte de Íons/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Microfluídica/métodos , Polímeros/química , Bloqueadores dos Canais de Potássio/efeitos adversos , Bloqueadores dos Canais de Potássio/farmacologia
13.
J Biol Chem ; 281(29): 20632-42, 2006 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-16707488

RESUMO

Clathrin-coated vesicles mediate sorting and intracellular transport of membrane-bound proteins. The formation of these coats is initiated by the assembly of adaptor proteins (AP), which specifically bind to membrane cargo proteins via recognition of endocytic sorting motifs. The lipid signaling molecule phosphatidylinositol 4,5-bisphosphate (PI(4,5)P(2)) is critical for this process, as it serves as both a targeting and regulatory factor. PI(4,5)P(2) is synthesized by type I phosphatidylinositol phosphate kinases (PIPKI). We have discovered a direct interaction between the mu2-subunit of the AP2 complex and PIPKIgamma661 via a yeast two-hybrid screen. This interaction was confirmed using both the mu2-subunit in glutathione S-transferase pulldowns and via coimmunoprecipitation of endogenous PIPKIgamma661 with the AP2 complex from HEK293 cells. The interaction is mediated, in vivo, by a tyrosine-based motif in the 26-amino acid tail of PIPKIgamma661. Because AP2 regulates endocytosis of transferrin receptor from the plasma membrane, we also examined a role for PIPKIgamma661 using a flow cytometry endocytosis assay. We observed that stable expression of wild type PIPKIgamma661 in Madin-Darby canine kidney cells enhanced transferrin uptake, whereas stable expression of kinase-dead PIPKIgamma661 had an inhibitory effect. Neither condition affected the overall cellular level of PI(4,5)P(2). RNA interference-based knockdown of PIPKIgamma661 in HeLa cells also had an inhibitory effect on transferrin endocytosis using the same assay system. Collectively, this evidence implies an important role for PIPKIgamma661 in the AP2-mediated endocytosis of transferrin.


Assuntos
Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fator de Transcrição AP-2/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Cães , Endocitose , Células HeLa , Humanos , Camundongos , Antígenos de Histocompatibilidade Menor , Dados de Sequência Molecular , Fosfatos de Fosfatidilinositol/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/química , Subunidades Proteicas/metabolismo , Receptores da Transferrina/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Fator de Transcrição AP-2/química , Transferrina/metabolismo
14.
J Cell Biochem ; 88(5): 1012-24, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12616538

RESUMO

PECAM-1 (CD31) is a member of immunoglobulin gene superfamily, which is highly expressed on the surface of endothelial cells and at moderate levels on hematopoietic cells. Hematopoietic cells and platelets, like endothelial cells, express multiple isoforms of PECAM-1. However, the identity and physiological role of these isoforms during hematopoiesis remains largely unknown. Here we demonstrate that PECAM-1 expression is dramatically up regulated upon phorbol myristate acetate (PMA) or transforming growth factor (TGF)-beta1-mediated differentiation of leukemic HEL and U937 cells. The level of PECAM-1 expression did not significantly change during activation of Jurkat T cells by PMA or phytohaemagglutinin (PHA). Utilizing RT-PCR and DNA sequencing analysis, we show that the expression of PECAM-1 isoforms changes in a cell-type and lineage specific manner during cellular differentiation and activation. We identified a number of novel PECAM-1 isoforms previously not detected in the endothelium. These results demonstrate that regulated expression of PECAM-1 and its exonic inclusion/exclusion occurs during differentiation and/or activation of hematopoietic cells. Thus, different PECAM-1 isoforms may play important roles in generation of hematopoietic cells and their potential interactions with vascular endothelium.


Assuntos
Processamento Alternativo/fisiologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/fisiologia , Processamento Alternativo/efeitos dos fármacos , Sequência de Aminoácidos , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Inflamação/metabolismo , Células Jurkat , Dados de Sequência Molecular , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA/análise , RNA/isolamento & purificação , Acetato de Tetradecanoilforbol/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1
15.
Am J Physiol Heart Circ Physiol ; 284(3): H1008-17, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12433657

RESUMO

Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell adhesion molecule that is highly expressed on the surface of endothelial cells and some hematopoietic cells. Its cytoplasmic domain is encoded by multiple exons, which undergo alternative splicing. Here, we demonstrate that the human PECAM-1 cytoplasmic domain undergoes alternative splicing, generating six different isoforms. RT-PCR cloning and DNA sequence analysis indicated that human tissue and endothelial cells express multiple isoforms of PECAM-1, including the full-length PECAM-1 and five other isoforms, which lack exon 12, 13, 14, or 15 or exons 14 and 15. The full-length PECAM-1 is the predominant isoform detected in human tissue and endothelial cells. This is in contrast to murine endothelium, in which the PECAM-1 isoform lacking exons 14 and 15 is the predominant isoform. The PECAM-1 isoform lacking exon 13 detected in human tissue and endothelial cells is absent in murine endothelium. The expression pattern of PECAM-1 isoforms changes during tube formation of endothelial cells on Matrigel, which may indicate specialized roles for specific isoforms of PECAM-1 during angiogenesis. The data presented here demonstrate that human PECAM-1 undergoes alternative splicing, generating multiple isoforms in vascular beds of various tissues. Therefore, the regulated expression of these isoforms may influence endothelial cell adhesive properties during angiogenesis and/or vasculogenesis.


Assuntos
Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Processamento Alternativo/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Diferenciação Celular/fisiologia , Linhagem Celular , Colágeno/farmacologia , Combinação de Medicamentos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Laminina/farmacologia , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Proteoglicanas/farmacologia , RNA Mensageiro/metabolismo
16.
Carcinogenesis ; 23(9): 1433-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12189184

RESUMO

Dietary phenethyl isothiocyanate (PEITC) and a mixture of dietary PEITC and benzyl isothiocyanate (BITC) inhibit lung tumorigenesis in A/J mice induced by a mixture of the tobacco smoke carcinogens benzo[a]pyrene (B[a]P) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In this study, we tested the hypothesis that inhibition of tumorigenesis by these isothiocyanates was due to inhibition of DNA adduct formation. We quantified the following pulmonary DNA adducts: N2-[7,8,9-trihydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene-10-yl]deoxyguanosine (BPDE-N2-dG) from B[a]P; and O(6)-methylguanine (O(6)-mG) and 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing adducts from NNK. Initial experiments demonstrated that there were no effects of B[a]P on NNK-DNA adduct formation, or vice versa, and established by way of a time course study the appropriate sacrifice intervals for the main experiment. Dietary PEITC, or dietary BITC plus PEITC, inhibited the formation of HPB-releasing DNA adducts of NNK at several of the time points examined. There were no effects of dietary isothiocyanates on levels of O(6)-mG or BPDE-N2-dG. These results, which are consistent with previous studies in rats and with tumor inhibition data in mice, support a role for inhibition of HPB-releasing DNA adducts of NNK as a mechanism of inhibition of tumorigenesis by dietary PEITC and BITC plus PEITC. However, the observed inhibition was modest, suggesting that other effects of isothiocyanates are also involved in chemoprevention in this model.


Assuntos
Benzo(a)pireno/farmacologia , Carcinógenos/farmacologia , Adutos de DNA/efeitos dos fármacos , Isotiocianatos/farmacologia , Pulmão/efeitos dos fármacos , Nitrosaminas/farmacologia , Animais , DNA/efeitos dos fármacos , DNA/metabolismo , Interações Medicamentosas , Feminino , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos A
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