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Impact of cirrhosis on outcomes in trauma 总被引:2,自引:0,他引:2
Dangleben DA Jazaeri O Wasser T Cipolle M Pasquale M 《Journal of the American College of Surgeons》2006,203(6):908-913
BACKGROUND: Cirrhosis as an independent predictor of poor outcomes in trauma patients was identified in 1990. We hypothesized that the degree of preinjury hepatic dysfunction is, by itself, an independent predictor of mortality. STUDY DESIGN: The trauma registry at our Level I trauma center was queried for all ICD-9 codes for liver disease from 1999 to 2003, and patients were categorized as having Child-Turcotte-Pugh (CTP) class A, B, or C cirrhosis. Data analyzed included age, mechanism of injury, Abbreviated Injury Score (AIS), Injury Severity Score (ISS), Glasgow Coma Score (GCS), hospital length of stay, ventilator days, procedures performed, transfusion of blood products, admission lactate, base deficit, and mortality. Trauma Related Injury Severity Score (TRISS) methodology was used to calculate the probability of survival. Outcomes data were analyzed, and statistical comparison was performed using group t-test. RESULTS: Of the 50 patients meeting study criteria, 31 had alcohol-related cirrhosis, 18 had a history of hepatitis C, and 1 had cryptogenic cirrhosis. Twenty (40%) met CTP A classification, 16 (32%) met CTP B criteria, and 14 (28%) had CTP class C cirrhosis. One death occurred in the CTP A and B groups. Comparison between the five survivors and nine nonsurvivors from CTP class C showed no statistical significance in terms of age, ISS, TRISS, or GCS. CONCLUSIONS: The mortality rate for class C cirrhotic patients posttrauma continues to be higher than that predicted by TRISS, although patients with less severe hepatic dysfunction do not appear to have significantly lower than predicted survival. The degree of hepatic dysfunction remains an independent predictor of mortality and CTP C criteria must be considered when determining outcomes for patients posttrauma. 相似文献
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Marjan Joudi Azra Izanloo Omid Montazeri Ali Jangjoo 《The International journal of clinical and experimental hypnosis》2016,64(3):365-372
Little attention has been paid to the effectiveness of hypnosis in improving the results of surgery in Iran. One hundred and twenty patients scheduled for laparoscopic cholecystectomy were randomly divided into either control (standard care) or experimental (hypnosis) groups. Prior to surgery and again after surgery, abdominal pain, nausea, and vomiting were assessed. The results suggest that hypnosis could effectively reduce pain after laparoscopic cholecystectomy and significantly reduce hospitalization time. 相似文献
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YongTae Kim Mark E. Lobatto Tomohiro Kawahara Bomy Lee Chung Aneta J. Mieszawska Brenda L. Sanchez-Gaytan Francois Fay Max L. Senders Claudia Calcagno Jacob Becraft May Tun Saung Ronald E. Gordon Erik S. G. Stroes Mingming Ma Omid C. Farokhzad Zahi A. Fayad Willem J. M. Mulder Robert Langer 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(3):1078-1083
Therapeutic and diagnostic nanomaterials are being intensely studied for several diseases, including cancer and atherosclerosis. However, the exact mechanism by which nanomedicines accumulate at targeted sites remains a topic of investigation, especially in the context of atherosclerotic disease. Models to accurately predict transvascular permeation of nanomedicines are needed to aid in design optimization. Here we show that an endothelialized microchip with controllable permeability can be used to probe nanoparticle translocation across an endothelial cell layer. To validate our in vitro model, we studied nanoparticle translocation in an in vivo rabbit model of atherosclerosis using a variety of preclinical and clinical imaging methods. Our results reveal that the translocation of lipid–polymer hybrid nanoparticles across the atherosclerotic endothelium is dependent on microvascular permeability. These results were mimicked with our microfluidic chip, demonstrating the potential utility of the model system.Improving the design of nanomedicines is key for their success and ultimate clinical application (1). The accumulation of such therapeutic or diagnostic nanomaterials primarily relies on enhanced endothelial permeability of the microvasculature in diseased tissue (2). This holds true for a wide range of pathological conditions, including inflammation, atherosclerosis, and most notably, oncological disease (3–6). Although attributed to the enhanced permeability and retention (EPR) effect, the exact mechanism by which nanoparticles accumulate in tumors continues to be a topic of research (7, 8). The “leaky” vasculature of tumors, which facilitates the extravasation of nanoparticles from microvessels (9), is a heterogeneous phenomenon that varies between different tumor models and even more so in patients. Moreover, the exploitation of nanomedicines in other conditions with enhanced microvessel permeability has only recently begun to be studied in detail. For example, in the last 5 y, a small but increasing number of preclinical studies that apply nanoparticle therapy in atherosclerosis models has surfaced (10). Although several targeting mechanisms have been proposed (4), the exact mechanism by which nanoparticles accumulate in atherosclerotic plaques remains to be investigated, but is likely facilitated by highly permeable neovessels that penetrate into the plaque from the vasa vasorum (Fig. 1A), a network of microvessels that supplies the wall of larger vessels (11).Open in a separate windowFig. 1.Development of an endothelialized microfluidic device to probe nanoparticle translocation over a permeable microvessel. (A) Schematics of continuous normal capillaries surrounding the vessel wall as well as permeable capillaries that penetrate into the atherosclerotic plaque from the vasa vasorum. (B) Schematic of an endothelialized microfluidic device that consists of two-layer microfluidic channels that are separated by a porous membrane (3 μm pore) on which ECs are grown. (C) TEER was dynamically measured across the endothelial layer on the membrane between the upper and lower channels. (D) A well-established monolayer of the microvascular endothelium is formed at TEER ∼400 (Ω·cm2). (E) The monolayer becomes highly permeable when stimulated with the inflammatory mediator, TNF-α, as well as with shear stress, with disruption of intercellular junctional structures (i.e., adherens junctions) between ECs, as evidenced by patchy expression of VE–cadherin (green) in the image on the right versus the left. Blue depicts nuclei stained with DAPI. (Scale bar, 20 μm.) (F) FITC–albumin translocation through the endothelial monolayer increases when the chip is treated with TNF-α. (G) The chip with endothelium cultured in different culture media [base, +FBS, +growth factors (GFs)] for 6 h shows a decrease in TEER with increased FITC–albumin translocation. No cell indicates the membrane only. TEER was normalized to the level with no cells (membrane only). (H) Schematic and TEM image of PEGylated lipid-coated nanoparticles encapsulating PLGA-conjugated AuNCs and Cy5.5. The average size was 69.7 ± 14 nm, which was measured from TEM images. (Scale bar, 100 nm.) Details on labeling, synthesis, characterization, and large-scale production procedures can be found in Materials and Methods and Fig. S2.Advances in biomedical imaging allow the study of plaque-targeting nanoparticles in a dynamic fashion with exceptional detail (12, 13). Microchip technology has the potential to monitor nanoparticle behavior at the (sub)cellular level. Microfluidic chips in which endothelial cells (ECs) are grown in the channels can serve as unique in vitro test systems to study microvascular function and associated disorders (14–18). They allow the isolation of specific biological hallmarks relevant to nanoparticle accumulation, such as the leaky endothelium. In the current study, we validate the potential utility of our microchip technology to study nanoparticle translocation over the endothelium and combine this with in vivo and ex vivo multimodality imaging studies on a rabbit model to better understand nanoparticle targeting of atherosclerotic plaques. 相似文献
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Archana Swami Michaela R. Reagan Pamela Basto Yuji Mishima Nazila Kamaly Siobhan Glavey Sufeng Zhang Michele Moschetta Dushanth Seevaratnam Yong Zhang Jinhe Liu Masoumeh Memarzadeh Jun Wu Salomon Manier Jinjun Shi Nicolas Bertrand Zhi Ning Lu Kenichi Nagano Roland Baron Antonio Sacco Aldo M. Roccaro Omid C. Farokhzad Irene M. Ghobrial 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(28):10287-10292
Bone is a favorable microenvironment for tumor growth and a frequent destination for metastatic cancer cells. Targeting cancers within the bone marrow remains a crucial oncologic challenge due to issues of drug availability and microenvironment-induced resistance. Herein, we engineered bone-homing polymeric nanoparticles (NPs) for spatiotemporally controlled delivery of therapeutics to bone, which diminish off-target effects and increase local drug concentrations. The NPs consist of poly(d,l-lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), and bisphosphonate (or alendronate, a targeting ligand). The engineered NPs were formulated by blending varying ratios of the synthesized polymers: PLGA-b-PEG and alendronate-conjugated polymer PLGA-b-PEG-Ald, which ensured long circulation and targeting capabilities, respectively. The bone-binding ability of Ald-PEG-PLGA NPs was investigated by hydroxyapatite binding assays and ex vivo imaging of adherence to bone fragments. In vivo biodistribution of fluorescently labeled NPs showed higher retention, accumulation, and bone homing of targeted Ald-PEG-PLGA NPs, compared with nontargeted PEG-PLGA NPs. A library of bortezomib-loaded NPs (bone-targeted Ald-Bort-NPs and nontargeted Bort-NPs) were developed and screened for optimal physiochemical properties, drug loading, and release profiles. Ald-Bort-NPs were tested for efficacy in mouse models of multiple myeloma (MM). Results demonstrated significantly enhanced survival and decreased tumor burden in mice pretreated with Ald-Bort-NPs versus Ald-Empty-NPs (no drug) or the free drug. We also observed that bortezomib, as a pretreatment regimen, modified the bone microenvironment and enhanced bone strength and volume. Our findings suggest that NP-based anticancer therapies with bone-targeting specificity comprise a clinically relevant method of drug delivery that can inhibit tumor progression in MM.The incidence of bone metastasis is common in 60–80% of cancer patients (1). During bone metastasis, cancer cells induce a sequence of changes in the microenvironment such as secreting cytokines to increase the activity of osteoclasts via the parathyroid hormone-related protein (PTHrP), receptor activator of nuclear factor-κB ligand (RANKL), and interleukin-6 (IL-6), resulting in increased bone resorption and secretion of growth factors from the bone matrix (2). This creates a “vicious cycle” of bone metastasis, where bone marrow becomes packed with cancer cells that develop resistance to conventional chemotherapy, and leads to devastating consequences of bone fractures, pain, hypercalcaemia, and spinal cord and nerve compression syndromes (2, 3). Multiple myeloma (MM) is a plasma cell cancer that proliferates primarily in bone marrow and causes osteolytic lesions (1). Antiresorption agents, such as bisphosphonates, may alleviate bone pain, but they are ineffective at inducing bone healing or osteogenesis in MM patients (4).Bortezomib is a proteasome inhibitor that has shown marked antitumor effects in patients with MM. Proteasome inhibitors, such as bortezomib, are also effective at increasing bone formation, both preclinically and clinically (5–9). However, the major drawback of bortezomib use in early stages of MM development is its toxicity, specifically, peripheral neuropathy (5). Therefore, we aimed to develop a method to deliver bortezomib with decreased off-target side effects by using bone-specific, bortezomib-loaded nanoparticles (NPs). The NP system was based on biodegradable, biocompatible, and Food and Drug Administration (FDA)-approved components, which are both clinically and translationally relevant. NPs derived from poly(d,l-lactic-co-glycolic acid) (PLGA), a controlled release polymer system, are an excellent choice because their safety in the clinic is well established (10, 11). Polyethylene glycol (PEG)-functionalized PLGA NPs are especially desirable as PEGylated polymeric NPs have significantly reduced systemic clearance compared with similar particles without PEG (12, 13). A number of FDA-approved drugs in clinical practice use PEG for improved pharmaceutical properties such as enhanced circulation in vivo (12, 13). To target NPs to bone [rich in the mineral hydroxyapatite (HA)], the calcium ion-chelating molecules of bisphosphonates represent a promising class of ligands (14). Bisphosphonates, upon systemic administration, are found to deposit in bone tissue, preferentially at the high bone turnover sites, such as the metastatic bone lesions, with minimal nonspecific accumulation (14) and were used herein to deliver NPs to the bone.A few systems explored for MM treatment have been tested in vitro including the following: (i) snake venom and silica NPs (15); (ii) thymoquinone and PLGA-based particles (16); (iii) curcumin and poly(oxyethylene) cholesteryl ether (PEG-Chol) NPs (17), polyethylenimine-based NPs for RNAi in MM (18), paclitaxel-Fe3O4 NPs (19), and liposomes (20). However, none of the above-mentioned systems have aimed to manipulate the bone marrow microenvironment rather than the myeloma cells directly (21). To date, there are no reports of using bone-targeted, controlled release, polymeric NPs with stealth properties for MM therapy. In this study, we designed NPs bearing three main components: (i) a targeting element that can selectively bind to bone mineral; (ii) a layer of stealth (PEG) to minimize immune recognition and enhance circulation; and (iii) a biodegradable polymeric material, forming an inner core, that can deliver therapeutics and/or diagnostics in a controlled manner. In this study, the physicochemical properties of a range of NPs was investigated (including NP size, charge, targeting ligand density, drug loading, and drug release kinetics) and an optimal formulation with ideal properties and maximal drug encapsulation was used for in vivo efficacy studies. We fine-tuned the NP targeting ligand density to optimize its bone-binding ability and further investigated its application for targeting myeloma in the bone microenvironment. We believe our NP system has the potential to increase drug availability by improving pharmacokinetics and biodistribution that can provide bone microenvironment specificity, which may increase the therapeutic window and most certainly decrease the off-target effects (12, 13). 相似文献
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Masoud Alirezaei Omid Dezfoulian Ali Sookhtehzari Peyman Asadian Zeynab Khoshdel 《Comparative clinical pathology》2014,23(5):1359-1365
Purified oleuropein from olive leaf extract indicated antioxidant properties in our previous reports. The recent study demonstrated that the lesions of absolute ethanol could be attributed to the increasing reactive oxygen species, subsequently lipid peroxidation and gastric ulcers. Therefore, the antioxidant effects of oleuropein as a natural antioxidant agent on intestine mucosal damages induced by absolute ethanol were investigated in the present study. The 42 adult male rats were divided into four (control, oleuropein, ethanol, and oleuropein plus ethanol) groups. Oleuropein at a dosage of 12 mg/kg was used for 10 consecutive days in oleuropein and oleuropein plus ethanol groups, thereafter absolute ethanol (once, 1 ml/rat) was administrated orally in ethanol and oleuropein plus ethanol groups at fasting state by gavage. The duodena of rats were removed for histopathology and antioxidant assay. Histological evidence of severe mucosal damages were confirmed by histopathology findings in ethanol group and prevented in oleuropein plus ethanol group. In this setting, glutathione peroxidase and catalase activities were significantly higher in oleuropein and oleuropein plus ethanol groups than the ethanol-treated rats. In contrast, thiobarbituric acid reactive substances concentration (as a lipid peroxidation marker) significantly increased in ethanol-treated rats when compared to the other groups. Our results suggest that olive leaf extract (containing oleuropein) exerts a potent antioxidant agent against oxidative stress. These findings allow us to exploit the advantages of oleuropein treatment in various diseases induced by oxidative stress in humans. 相似文献