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1.
Int J Mol Sci ; 24(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37958720

RESUMO

As a member of the HPSG family, heparin is often used as a specific probe of their role in cell physiology; indeed, we have previously shown a reduction in the tumorigenicity of breast cancer cells when cultured in its presence. However, a partial reversal of the anti-tumorigenic effect occurred when the treated cells were cultured in fresh medium without heparin, which led us to consider whether a more persistent effect could be achieved by treatment of the cells with small extracellular vesicles (sEV) from heparin-treated cells. The tumorigenicity was analyzed using sEV isolated from the culture medium of heparin-treated MCF-7 and MDA-MB231 breast cancer cells (sEV-HT) or from conditioned medium following the termination of treatment (heparin discontinued, sEV-HD). Tumorigenicity was reduced in cells cultured in the presence of sEV-HT compared to that of cells cultured in the presence of sEV from untreated cells (sEV-Ctrl). sEV-HD were also observed to exert an anti-tumorigenic effect on the expression of pro-tumorigenic and cell cycle regulatory proteins, as well as signaling activities when added to fresh cultures of MCF-7 and MDA-MB231 cells. The anti-tumorigenic activity of the heparin-derived sEV may arise from observed changes in the miRNA content or from heparin, which was observed to be bound to the sEV. sEV may constitute a relatively stable reservoir of circulating heparin, allowing heparin activity to persist in the circulation even after therapy has been discontinued. These findings can be considered as a special additional pharmacological characteristic of heparin clinical therapy.


Assuntos
Vesículas Extracelulares , Heparina , Humanos , Heparina/farmacologia , Técnicas de Cultura de Células , Carcinogênese , Proteínas de Ciclo Celular
2.
Appl Ergon ; 109: 103990, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36791557

RESUMO

BACKGROUND: Training clinicians on the use of hospital-based patient monitoring systems (PMS) is vital to mitigate the risk of use errors and of frustration using these devices, especially when used in ICU settings. PMS training is typically delivered through face-to-face training sessions in the hospital. However, it is not always feasible to deliver training in this format to all clinical staff given some constraints (e.g., availability of staff and trainers to attend in-person training sessions and the costs associated with face-to-face training). OBJECTIVE: The literature indicates that E-learning has the potential to mitigate barriers associated with time restrictions for trainers and trainees and evidence shows it to be more flexible, and convenient for learners in healthcare settings. This study aimed to develop and carry out a preliminary evaluation via a case study of an e-learning training platform designed for a novel neonatal sepsis risk monitor system (Digi-NewB). METHODS: A multi-modal qualitative research case study approach was used, including the analysis of three qualitative data sources: (i) audio/video recordings of simulation sessions in which participants were asked to operate the system as intended (e.g., update the clinical observations and monitor the sepsis risk), (ii) interviews with the simulation participants and an attending key opinion leader (KOL), who observed all simulation sessions, and (iii) post-simulation survey. RESULTS: After receiving ethical approval for the study, nine neonatal intensive care unit (NICU) nurses completed the online training and participated in the simulation and follow-up interview sessions. The KOL was also interviewed, and seven out of the nine NICU nurses answered the post-simulation survey. The video/audio analysis of the simulations revealed that participants were able to use and interpret the Digi-NewB interface. Interviews with simulation participants and the KOL, and feedback extracted from the survey, revealed that participants were overall satisfied with the training platform and perceived it as an efficient and effective method to deliver medical device training. CONCLUSIONS: This study developed an online training platform to train clinicians in the use of a critical care medical device and carried out a preliminary evaluation of the platform via a case study. The e-learning platform was designed to supplement and enhance other training approaches. Further research is required to evaluate the effectiveness of this approach.


Assuntos
Instrução por Computador , Sepse Neonatal , Recém-Nascido , Humanos , Aprendizagem , Inquéritos e Questionários , Unidades de Terapia Intensiva
3.
Int J Mol Sci ; 22(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34884645

RESUMO

BACKGROUND: Ventilator-induced lung injury (VILI) frequently worsens acute respiratory distress syndrome (ARDS) severity. Human mesenchymal stem/stromal cells (MSCs) offer considerable therapeutic promise, but the key impediments of clinical translation stem from limitations due to cell source and availability, and concerns regarding the loss of efficacy following cryopreservation. These experiments compared the efficacy of umbilical-cord-derived MSCs (UC-MSCs), a readily available and homogenous tissue source, to the previously more widely utilised bone-marrow-derived MSCs (BM-MSCs). We assessed their capacity to limit inflammation, resolve injury and enhance repair in relevant lung mechanical stretch models, and the impact of cryopreservation on therapeutic efficacy. METHODS: In series 1, confluent alveolar epithelial layers were subjected to cyclic mechanical stretch (22% equibiaxial strain) and wound injury, and the potential of the secretome from BM- and UC-derived MSCs to attenuate epithelial inflammation and cell death, and enhance wound repair was determined. In series 2, anesthetized rats underwent VILI, and later received, in a randomised manner, 1 × 107 MSCs/kg intravenously, that were: (i) fresh BM-MSCs, (ii) fresh UC-MSCs or (iii) cryopreserved UC-MSCs. Control animals received a vehicle (PBS). The extent of the resolution of inflammation and injury, and repair was measured at 24 h. RESULTS: Conditioned medium from BM-MSCs and UC-MSCs comparably decreased stretch-induced pulmonary epithelial inflammation and cell death. BM-MSCs and UC-MSCs comparably enhanced wound resolution. In animals subjected to VILI, both fresh BM-MSCs and UC-MSCs enhanced injury resolution and repair, while cryopreserved UC-MSCs comparably retained their efficacy. CONCLUSIONS: Cryopreserved UC-MSCs can reduce stretch-induced inflammation and cell death, enhance wound resolution, and enhance injury resolution and repair following VILI. Cryopreserved UC-MSCs represent a more abundant, cost-efficient, less variable and equally efficacious source of therapeutic MSC product.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Lesão Pulmonar Induzida por Ventilação Mecânica/terapia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Criopreservação/métodos , Meios de Cultivo Condicionados , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Síndrome do Desconforto Respiratório/metabolismo , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/terapia , Cordão Umbilical/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
4.
JMIR Hum Factors ; 8(2): e16491, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34032574

RESUMO

BACKGROUND: Continuous monitoring of the vital signs of critical care patients is an essential component of critical care medicine. For this task, clinicians use a patient monitor (PM), which conveys patient vital sign data through a screen and an auditory alarm system. Some limitations with PMs have been identified in the literature, such as the need for visual contact with the PM screen, which could result in reduced focus on the patient in specific scenarios, and the amount of noise generated by the PM alarm system. With the advancement of material science and electronic technology, wearable devices have emerged as a potential solution for these problems. This review presents the findings of several studies that focused on the usability and human factors of wearable devices designed for use in critical care patient monitoring. OBJECTIVE: The aim of this study is to review the current state of the art in wearable devices intended for use by clinicians to monitor vital signs of critical care patients in hospital settings, with a focus on the usability and human factors of the devices. METHODS: A comprehensive literature search of relevant databases was conducted, and 20 studies were identified and critically reviewed by the authors. RESULTS: We identified 3 types of wearable devices: tactile, head-mounted, and smartwatch displays. In most cases, these devices were intended for use by anesthesiologists, but nurses and surgeons were also identified as potentially important users of wearable technology in critical care medicine. Although the studies investigating tactile displays revealed their potential to improve clinical monitoring, usability problems related to comfort need to be overcome before they can be considered suitable for use in clinical practice. Only a few studies investigated the usability and human factors of tactile displays by conducting user testing involving critical care professionals. The studies of head-mounted displays (HMDs) revealed that these devices could be useful in critical care medicine, particularly from an ergonomics point of view. By reducing the amount of time the user spends averting their gaze from the patient to a separate screen, HMDs enable clinicians to improve their patient focus and reduce the potential of repetitive strain injury. CONCLUSIONS: Researchers and designers of new wearable devices for use in critical care medicine should strive to achieve not only enhanced performance but also enhanced user experience for their users, especially in terms of comfort and ease of use. These aspects of wearable displays must be extensively tested with the intended end users in a setting that properly reflects the intended context of use before their adoption can be considered in clinical settings.

5.
Int J Mol Sci ; 21(21)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158246

RESUMO

Mesenchymal stromal cells (MSCs) have a multimodal, immunomodulatory mechanism of action and are now in clinical trials for single organ and systemic sepsis. However, a number of practicalities around source, homogeneity and therapeutic window remain to be determined. Here, we utilised conditioned medium from CD362+-sorted umbilical cord-human MSCs (UC-hMSCs) for a series of in vitro anti-inflammatory assays and the cryopreserved MSCs themselves in a severe (Series 1) or moderate (Series 2+3) caecal ligation and puncture (CLP) rodent model. Surviving animals were assessed at 48 h post injury induction. MSCs improved human lung, colonic and kidney epithelial cell survival following cytokine activation. In severe systemic sepsis, MSCs administered at 30 min enhanced survival (Series 1), and reduced organ bacterial load. In moderate systemic sepsis (Series 2), MSCs were ineffective when delivered immediately or 24 h later. Of importance, MSCs delivered 4 h post induction of moderate sepsis (Series 3) were effective, improving serum lactate, enhancing bacterial clearance from tissues, reducing pro-inflammatory cytokine concentrations and increasing antimicrobial peptides in serum. While demonstrating benefit and immunomodulation in systemic sepsis, therapeutic efficacy may be limited to a specific point of disease onset, and repeat dosing, MSC enhancement or other contingencies may be necessary.


Assuntos
Ceco/microbiologia , Coinfecção/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Sepse/terapia , Animais , Antígenos CD/metabolismo , Ceco/patologia , Ceco/cirurgia , Células Cultivadas , Coinfecção/complicações , Coinfecção/etiologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Modelos Animais de Doenças , Humanos , Ligadura/efeitos adversos , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Punções/efeitos adversos , Ratos , Ratos Sprague-Dawley , Sepse/etiologia , Sepse/microbiologia , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo
6.
JMIR Hum Factors ; 7(3): e15052, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32618574

RESUMO

BACKGROUND: The patient monitor (PM) is one of the most commonly used medical devices in hospitals worldwide. PMs are used to monitor patients' vital signs in a wide variety of patient care settings, especially in critical care settings, such as intensive care units. An interesting observation is that the design of PMs has not significantly changed over the past 2 decades, with the layout and structure of PMs more or less unchanged, with incremental changes in design being made rather than transformational changes. Thus, we believe it well-timed to review the design of novel PM interfaces, with particular reference to usability and human factors. OBJECTIVE: This paper aims to review innovations in PM design proposed by researchers and explore how clinicians responded to these design changes. METHODS: A literature search of relevant databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, identified 16 related studies. A detailed description of the interface design and an analysis of each novel PM were carried out, including a detailed analysis of the structure of the different user interfaces, to inform future PM design. The test methodologies used to evaluate the different designs are also presented. RESULTS: Most of the studies included in this review identified some level of improvement in the clinician's performance when using a novel display in comparison with the traditional PM. For instance, from the 16 reviewed studies, 12 studies identified an improvement in the detection and response times, and 10 studies identified an improvement in the accuracy or treatment efficiency. This indicates that novel displays have the potential to improve the clinical performance of nurses and doctors. However, the outcomes of some of these studies are weakened because of methodological deficiencies. These deficiencies are discussed in detail in this study. CONCLUSIONS: More careful study design is warranted to investigate the user experience and usability of future novel PMs for real time vital sign monitoring, to establish whether or not they could be used successfully in critical care. A series of recommendations on how future novel PM designs and evaluations can be enhanced are provided.

7.
Intensive Care Med Exp ; 8(1): 8, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32025852

RESUMO

BACKGROUND: Human mesenchymal stem/stromal cells (hMSCs) represent a promising therapeutic strategy for ventilator-induced lung injury (VILI) and acute respiratory distress syndrome. Translational challenges include restoring hMSC efficacy following cryopreservation, developing effective xenogeneic-free (XF) hMSCs and establishing true therapeutic potential at a clinically relevant time point of administration. We wished to determine whether cytokine pre-activation of cryopreserved, bone marrow-derived XF-hMSCs would enhance their capacity to facilitate injury resolution following VILI and elucidate mechanisms of action. METHODS: Initially, in vitro studies examined the potential for the secretome from cytokine pre-activated XF-hMSCs to attenuate pulmonary epithelial injury induced by cyclic mechanical stretch. Later, anaesthetised rats underwent VILI and, 6 h following injury, were randomized to receive 1 × 107 XF-hMSC/kg that were (i) naive fresh, (ii) naive cryopreserved, (iii) cytokine pre-activated fresh or (iv) cytokine pre-activated cryopreserved, while control animals received (v) vehicle. The extent of injury resolution was measured at 24 h after injury. Finally, the role of keratinocyte growth factor (KGF) in mediating the effect of pre-activated XF-hMSCs was determined in a pulmonary epithelial wound repair model. RESULTS: Pre-activation enhanced the capacity of the XF-hMSC secretome to decrease stretch-induced pulmonary epithelial inflammation and injury. Both pre-activated fresh and cryopreserved XF-hMSCs enhanced resolution of injury following VILI, restoring oxygenation, improving lung compliance, reducing lung leak and improving resolution of lung structural injury. Finally, the secretome of pre-activated XF-hMSCs enhanced epithelial wound repair, in part via a KGF-dependent mechanism. CONCLUSIONS: Cytokine pre-activation enhanced the capacity of cryopreserved, XF-hMSCs to promote injury resolution following VILI, potentially via a KGF-dependent mechanism.

8.
Int J Mol Sci ; 19(10)2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-30274394

RESUMO

: Alveolar epithelial dysfunction induced by hypoxic stress plays a significant role in the pathological process of lung ischemia-reperfusion injury (IRI). Mesenchymal stem cell (MSC) therapies have demonstrated efficacy in exerting protective immunomodulatory effects, thereby reducing airway inflammation in several pulmonary diseases. AIM: This study assesses the protective effects of MSC secretome from different cell sources, human bone marrow (BMSC) and adipose tissue (ADSC), in attenuating hypoxia-induced cellular stress and inflammation in pulmonary epithelial cells. METHODS: Pulmonary epithelial cells, primary rat alveolar epithelial cells (AEC) and A549 cell line were pre-treated with BMSC, or ADSC conditioned medium (CM) and subjected to hypoxia for 24 h. RESULTS: Both MSC-CM improved cell viability, reduced secretion of pro-inflammatory mediators and enhanced IL-10 anti-inflammatory cytokine production in hypoxic injured primary rat AECs. ADSC-CM reduced hypoxic cellular injury by mechanisms which include: inhibition of p38 MAPK phosphorylation and nuclear translocation of subunits in primary AECs. Both MSC-CM enhanced translocation of Bcl-2 to the nucleus, expression of cytoprotective glucose-regulated proteins (GRP) and restored matrix metalloproteinases (MMP) function, thereby promoting repair and cellular homeostasis, whereas inhibition of GRP chaperones was detrimental to cell survival. CONCLUSIONS: Elucidation of the protective mechanisms exerted by the MSC secretome is an essential step for maximizing the therapeutic effects, in addition to developing therapeutic targets-specific strategies for various pulmonary syndromes.


Assuntos
Tecido Adiposo/citologia , Células da Medula Óssea/citologia , Epitélio/patologia , Hipóxia/complicações , Lesão Pulmonar/etiologia , Lesão Pulmonar/terapia , Células-Tronco Mesenquimais/metabolismo , Proteoma/metabolismo , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Anti-Inflamatórios/farmacologia , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Citoproteção , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Imunomodulação , Lesão Pulmonar/patologia , Masculino , Metaloproteinases da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Substâncias Protetoras , Ratos Sprague-Dawley
9.
Mil Med ; 182(3): e1858-e1860, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28290973

RESUMO

INTRODUCTION: Cardiac involvement by light-chain (AL) amyloid occurs in up to 50% of patients with primary AL amyloidosis. The prognosis of amyloid heart disease is poor with 1-year survival rates of 35 to 40%. Historically, heart transplantation was considered controversial for patients with AL amyloid cardiomyopathy (CM) given the systemic nature of the disease and poor survival. We present a case report of an active duty service member diagnosed with advanced cardiac amyloid who underwent total artificial heart transplant as a bridge to heart transplant and eventual autologous stem cell transplant. CASE REPORT: A 47-year-old active duty male initially evaluated for atypical chest pain was found to have severe concentric left ventricular hypertrophy on echocardiogram but normal voltage on electrocardiogram. Cardiac magnetic resonance imaging, laboratory studies, and bone marrow biopsy established the diagnosis of cardiac amyloidosis. At the time of diagnosis, the patient's prognosis was very poor with a median survival of 5 months on the basis of the Mayo Clinic revised prognostic staging system for amyloidosis. The patient developed rapidly progressive left ventricular dysfunction and heart failure leading to cardiac arrest. The patient received a total artificial heart as a bridge to orthotopic heart and kidney transplantation and eventual stem cell transplant. He continues to be in remission and has a fair functional capacity without restriction in activities of daily living or moderate exercise. DISCUSSION: Amyloid CM is a rare and devastating disease. The natural course of the disease has made heart transplant in these patients controversial. Modern advancements in chemotherapies and advanced heart failure treatments have improved outcomes for select patients with AL amyloid CM undergoing heart transplantation. There is ongoing research seeking improvement in treatment options and outcomes for patients with this deadly disease.


Assuntos
Amiloidose/complicações , Cardiomiopatias/complicações , Transplante de Coração , Coração Artificial , Militares , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/análise , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/sangue , Troponina T/análise , Troponina T/sangue
10.
Mol Immunol ; 83: 92-99, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28119207

RESUMO

CD27 is a T and B cell co-stimulatory protein of the TNF receptor superfamily dependent on the availability of the TNF-like ligand CD70. Two anti-CD27 neutralizing monoclonal antibodies were obtained from mouse hybridoma and subsequently humanized and optimized for binding the target. The two antibodies are similar in terms of their CD27-binding affinity and ability to block NF-κB signaling, however their clearance rates in monkeys are very different. The pharmacokinetics profiles could be epitope dependent. To identify the epitopes, we determined the crystal structure of the ternary complex between CD27 and the Fab fragments of these non-competing antibodies. The structure reveals the binding modes of the antibodies suggesting that their mechanisms of action are distinctly different and provides a possible explanation of the in vivo data.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacocinética , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Afinidade de Anticorpos , Ligante CD27/química , Ligante CD27/imunologia , Cristalografia por Raios X , Ensaio de Imunoadsorção Enzimática , Meia-Vida , Humanos , Macaca fascicularis , Camundongos
11.
Intensive Care Med Exp ; 4(1): 8, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27001525

RESUMO

BACKGROUND: Hypercapnia, with its associated acidosis (HCA), is a consequence of respiratory failure and is also seen in critically ill patients managed with conventional "protective" ventilation strategies. Nuclear factor kappa-B (NF-κB), a pivotal transcription factor, is activated in the setting of injury and repair and is central to innate immunity. We have previously established that HCA protects against ventilation-induced lung injury in vivo, potentially via a mechanism involving inhibition of NF-κB signaling. We wished to further elucidate the role and mechanism of HCA-mediated inhibition of the NF-κB pathway in attenuating stretch-induced injury in vitro. METHODS: Initial experiments examined the effect of HCA on cyclic stretch-induced inflammation and injury in human bronchial and alveolar epithelial cells. Subsequent experiments examined the role of the canonical NF-κB pathway in mediating stretch-induced injury and the mechanism of action of HCA. The contribution of pH versus CO2 in mediating this effect of HCA was also examined. RESULTS: Pulmonary epithelial high cyclic stretch (22 % equibiaxial strain) activated NF-κB, enhanced interleukin-8 (IL-8) production, caused cell injury, and reduced cell survival. In contrast, physiologic stretch (10 % strain) did not activate inflammation or cause cell injury. HCA reduced cyclic mechanical stretch-induced NF-κB activation, attenuated IL-8 production, reduced injury, and enhanced survival, in bronchial and alveolar epithelial cells, following shorter (24 h) and longer (120 h) cyclic mechanical stretch. Pre-conditioning with HCA was less effective than when HCA was applied after commencement of cell stretch. HCA prevented the stretch-induced breakdown of the NF-κB cytosolic inhibitor IκBα, while IκBα overexpression "occluded" the effect of HCA. These effects were mediated by a pH-dependent mechanism rather than via CO2 per se. CONCLUSIONS: HCA attenuates adverse mechanical stretch-induced epithelial injury and death, via a pH-dependent mechanism that inhibits the canonical NF-κB activation by preventing IκBα breakdown.

14.
Cancer Biol Ther ; 15(1): 135-45, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24253450

RESUMO

A major problem in cancer treatment is the development of resistance to chemotherapeutic agents, multidrug resistance (MDR), associated with increased activity of transmembrane drug transporter proteins which impair cytotoxic treatment by rapidly removing the drugs from the targeted cells. Previously, it has been shown that heparin treatment of cancer patients undergoing chemotherapy increases survival. In order to determine whether heparin is capable reducing MDR and increasing the potency of chemotherapeutic drugs, the cytoxicity of a number of agents toward four cancer cell lines (a human enriched breast cancer stem cell line, two human breast cancer cell lines, MCF-7 and MDA-MB-231, and a human lung cancer cell line A549) was tested in the presence or absence of heparin. Results demonstrated that heparin increased the cytotoxicity of a range of chemotherapeutic agents. This effect was associated with the ability of heparin to bind to several of the drug transport proteins of the ABC and non ABC transporter systems. Among the ABC system, heparin treatment caused significant inhibition of the ATPase activity of ABCG2 and ABCC1, and of the efflux function observed as enhanced intracellular accumulation of specific substrates. Doxorubicin cytoxicity, which was enhanced by heparin treatment of MCF-7 cells, was found to be under the control of one of the major non-ABC transporter proteins, lung resistance protein (LRP). LRP was also shown to be a heparin-binding protein. These findings indicate that heparin has a potential role in the clinic as a drug transporter modulator to reduce multidrug resistance in cancer patients.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Heparina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Antibióticos Antineoplásicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Humanos , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismo
15.
Thromb Haemost ; 109(6): 1148-57, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23571852

RESUMO

Heparansulfate-proteoglycans (HSPGs) interact via their polyanionic heparansulfate (HS) side chains with a variety of proteins on the cell surface or within the extracellular matrix membrane. The large number of heparin/HS binding proteins form a highly interconnected functional network, which has been termed as the heparin/HS interactome and is functionally linked to physiological and pathological processes. The aim of this study was to investigate the global effect of these protein-HSPG interactions on the tumourigenicity of two breast cancer cell lines (MCF-7 and MDA-MB-231). Cancer cells were cultured in serum-free medium and treated with a concentration of heparin which was capable of modulating HS/ligand interaction. Microarray analysis of MCF-7 cells cultured under these conditions showed that expression of 105 of 1,357 genes potentially related to the pathogenesis of breast neoplasm was significantly altered by heparin treatment. The changes in gene expression correlated with a less tumourigenic phenotype, including reduction of cell adhesive, invasive and migratory properties. These effects were associated with an inhibition of the PI3K/Akt and Raf/MEK/ERK signalling pathways. The modulatory effect of heparin on HS-associated activity was confirmed with one example of heparin/HS interactomes, transforming growth factor ß (TGFß). The innate TGFß activity of MCF-7 cells was reduced by heparin treatment, with specific interruption of the TGFß-Smad signalling pathway. The pro-tumourigenic contribution of the heparin/HS interactomes was verified in cells in which HSPG synthesis was blocked using ß-xyloside. In conclusion, the interaction between cell surface HPSGs and innate heparin/HS interactomes makes a significant contribution to the tumourigenicity.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Heparina/química , Heparitina Sulfato/química , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Movimento Celular , Meios de Cultura Livres de Soro/química , MAP Quinases Reguladas por Sinal Extracelular , Feminino , Heparina/análogos & derivados , Humanos , Ligantes , Sistema de Sinalização das MAP Quinases , Análise de Sequência com Séries de Oligonucleotídeos , Ligação Proteica , Proteoglicanas/química , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
16.
J Surg Res ; 175(1): 176-84, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21944479

RESUMO

BACKGROUND: Polymorphoneutrophils (PMNs) are activated by inflammatory mediators following splanchnic ischemia/reperfusion (I/R), potentially injuring organs such as the lung. As a result, some patients develop respiratory failure following abdominal aortic aneurysm repair. Pulmonary cyclooxygenase (COX)-2 protects against acid aspiration and bacterial instillation via lipoxins, a family of potent anti-inflammatory lipid mediators. We explored the role of COX-2 and lipoxin A(4) in experimental I/R-mediated lung injury. MATERIALS AND METHODS: Sprague-Dawley rats were assigned to one of the following five groups: (1) controls; (2) aortic cross-clamping for 45 min and reperfusion for 4 h (I/R group); (3) I/R and SC236, a selective COX-2 inhibitor; (4) I/R and aspirin; and (5) I/R and iloprost, a prostacyclin (PGI(2)) analogue. Lung injury was assessed by wet/dry ratio, myeloperoxidase (MPO) activity, and bronchoalveolar lavage (BAL) neutrophil counts. BAL levels of thromboxane, PGE(2), 6-keto-PGF(1)α (a hydrolysis product of prostacyclin), lipoxin A(4), and 15-epi-lipoxin A(4) were analyzed by enzyme immunoassay (EIA). Immunostaining for COX-2 was performed. RESULTS: I/R significantly increased tissue MPO, the wet/dry lung ratio, and neutrophil counts. These measures were significantly further aggravated by SC236 and improved by iloprost. I/R increased COX-2 immunostaining and both PGE(2) and 6-keto-PGF(1α) levels in BAL. SC236 markedly reduced these prostanoids and lipoxin A(4) compared with I/R alone. Iloprost markedly increased lipoxin A(4) levels. The deleterious effect of SC236 and the beneficial effect of iloprost was associated with a reduction and an increase, respectively, in lipoxin A(4) levels. CONCLUSIONS: Lipoxin A(4) warrants further evaluation as a mediator of COX-2 regulated lung protection.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Lipoxinas/metabolismo , Lesão Pulmonar/prevenção & controle , Pulmão/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Aspirina/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Modelos Animais de Doenças , Iloprosta/farmacologia , Lesão Pulmonar/metabolismo , Lesão Pulmonar/fisiopatologia , Masculino , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Sulfonamidas/farmacologia
17.
Exp Diabetes Res ; 2011: 910159, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21754921

RESUMO

Patients treated with recombinant human Epo demonstrate an improvement in insulin sensitivity. We aimed to investigate whether CNTO 530, a novel Epo receptor agonist, could affect glucose tolerance and insulin sensitivity. A single administration of CNTO 530 significantly and dose-dependently reduced the area under the curve in a glucose tolerance test in diet-induced obese and diabetic mice after 14, 21, and 28 days. HOMA analysis suggested an improvement in insulin sensitivity, and this effect was confirmed by a hyperinsulinemic-euglycemic clamp. Uptake of (14)C-2-deoxy-D-glucose indicated that animals dosed with CNTO 530 transported more glucose into skeletal muscle and heart relative to control animals. In conclusion, CNTO530 has a profound effect on glucose tolerance in insulin-resistant rodents likely because of improving peripheral insulin sensitivity. This effect was observed with epoetin-α and darbepoetin-α, suggesting this is a class effect, but the effect with these compounds relative to CNTO530 was decreased in duration and magnitude.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Receptores da Eritropoetina/agonistas , Proteínas Recombinantes de Fusão/farmacologia , Animais , Darbepoetina alfa , Diabetes Mellitus Experimental/etiologia , Diabetes Mellitus Experimental/fisiopatologia , Gorduras na Dieta/efeitos adversos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Epoetina alfa , Eritropoetina/análogos & derivados , Eritropoetina/farmacologia , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Resistência à Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/etiologia , Obesidade/metabolismo , Proteínas Recombinantes , Fatores de Tempo
18.
Heart Lung Circ ; 18(4): 277-88, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19117801

RESUMO

BACKGROUND: Allogenic blood transfusion may affect clinical outcomes negatively. Up to 20% of blood transfusions in the United States are associated with cardiac surgery and so strategies to conserve usage are of importance. This study compares administration according to physician's choice based on laboratory coagulation tests with application of a strict protocol based on the thromboelastograph (TEG). METHODS: Sixty-nine patients presenting for cardiac surgery were randomised to either study or control groups. In the study group a strict protocol was followed covering usage of all blood products according to TEG patterns. In the control group, the physician directed product administration with reference to activated partial thromboplastin time (APTT), international normalised ratio (INR), fibrinogen and platelet count. Bleeding, re-sternotomy, minimum haemoglobin, intubation time, and ICU stay were documented. RESULTS: TEG-based management reduced total product usage by 58.8% in the study group but this was not statistically significant. This was associated with a statistically insignificant trend towards better short-term outcomes. CONCLUSIONS: This pilot study suggests that a strict protocol for blood product replacement based on the TEG might be highly effective in reducing usage without impairing short-term outcome.


Assuntos
Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Procedimentos Cirúrgicos Cardíacos , Procedimentos Clínicos , Cuidados Intraoperatórios , Cuidados Pós-Operatórios , Tromboelastografia , Idoso , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Pessoa de Meia-Idade , Projetos Piloto , Testes de Função Plaquetária , Sistemas Automatizados de Assistência Junto ao Leito
19.
Diabetes ; 57(7): 1926-34, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18426860

RESUMO

OBJECTIVE: We have developed a novel platform for display and delivery of bioactive peptides that links the biological properties of the peptide to the pharmacokinetic properties of an antibody. Peptides engineered in the MIMETIBODY platform have improved biochemical and biophysical properties that are quite distinct from those of Fc-fusion proteins. CNTO736 is a glucagon-like peptide 1 (GLP-1) receptor agonist engineered in our MIMETIBODY platform. It retains many activities of native GLP-1 yet has a significantly enhanced pharmacokinetic profile. Our goal was to develop a long-acting GLP-1 receptor agonist with sustained efficacy. RESEARCH DESIGN AND METHODS: In vitro and in vivo activity of CNTO736 was evaluated using a variety of rodent cell lines and diabetic animal models. RESULTS: Acute pharmacodynamic studies in diabetic rodents demonstrate that CNTO736 reduces fasting and postprandial glucose, decreases gastric emptying, and inhibits food intake in a GLP-1 receptor-specific manner. Reduction of food intake following CNTO736 dosing is coincident with detection of the molecule in the circumventricular organs of the brain and activation of c-fos in regions protected by the blood-brain barrier. Diabetic rodents dosed chronically with CNTO736 have lower fasting and postprandial glucose and reduced body weight. CONCLUSIONS: Taken together, our data demonstrate that CNTO736 produces a spectrum of GLP-1 receptor-dependent actions while exhibiting significantly improved pharmacokinetics relative to the native GLP-1 peptide.


Assuntos
Tecido Adiposo/metabolismo , Glucose/metabolismo , Lactoferrina/farmacologia , Engenharia de Proteínas/métodos , Receptores de Glucagon/fisiologia , Transferrina/farmacologia , Tecido Adiposo/efeitos dos fármacos , Sequência de Aminoácidos , Ração Animal , Animais , Linhagem Celular , Receptor do Peptídeo Semelhante ao Glucagon 1 , Homeostase , Humanos , Rim , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Obesidade/etiologia , Obesidade/fisiopatologia , Receptores de Glucagon/agonistas , Receptores de Glucagon/efeitos dos fármacos
20.
Am J Respir Cell Mol Biol ; 37(4): 494-500, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17575078

RESUMO

Disintegrin and metalloprotease proteins (ADAMs) are membrane-anchored glycoproteins involved in cell adhesion, cell fusion, protein ecto-domain shedding, and intracellular signaling. We examined whether the disintegrin domain of ADAM-15 (named ddADAM-15) containing an Asp-Gly-Asp (RGD) integrin-binding motif could interfere with airway smooth muscle cell (ASMC) adhesion and migration. Recombinant ddADAM-15 adhered to human ASMCs with saturation kinetics, and was beta(1)-integrin dependent. ddADAM-15 inhibited the binding of fibrinogen but not of fibronectin to ASMCs. ddADAM-15 also inhibited platelet-derived growth factor (PDGF)-induced ASMC migration, and this was reversed by an anti-beta(1)-integrin antibody. PDGF induced the activation of phosphoinositol-3-kinase (PI3K) and p38 mitogen-activated protein kinase (MAPK), and selective inhibitors of these kinases inhibited PDGF-induced ASMC migration. ddADAM-15 did not inhibit PDGF-induced activation of PI3K or p38, thereby excluding these kinase pathways as a mechanism by which ddADAM-15 inhibits ASMC migration. ADAM-15 mRNA and protein were expressed under basal conditions, and both gene and protein expression were inhibited by PDGF. In summary, ddADAM-15 inhibits ASMC adhesion and migration through the beta(1)-integrin, without modulating signaling pathways involved in ASMC migratory responses.


Assuntos
Proteínas ADAM/química , Proteínas ADAM/farmacologia , Movimento Celular/efeitos dos fármacos , Proteínas de Membrana/química , Proteínas de Membrana/farmacologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Sistema Respiratório/citologia , Sistema Respiratório/efeitos dos fármacos , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Adesão Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Integrinas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Mutantes/farmacologia , Miócitos de Músculo Liso/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Sistema Respiratório/enzimologia
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