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1.
Clin Transplant ; 36(6): e14667, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35435293

RESUMO

Living donor liver transplantation was first developed to mitigate the limited access to deceased donor organs in Asia in the 1990s. This alternative liver transplantation option has become an established and widely practiced transplantation method for adult patients suffering from end-stage liver disease. It has successfully addressed the shortage of deceased donors. The Society for the Advancement of Transplant Anesthesia and the Korean Society of Transplant Anesthesia jointly reviewed published studies on the perioperative management of live donor liver transplant recipients. The review aims to offer transplant anesthesiologists and critical care physicians a comprehensive overview of the perioperative management of adult live liver transplantation recipients. We feature the status, outcomes, surgical procedure, portal venous decompression, anesthetic management, prevention of acute kidney injury, avoidance of blood transfusion, monitoring and therapeutic strategies of hemodynamic derangements, and Enhanced Recovery After Surgery protocols for liver transplant recipients.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Adulto , Transfusão de Sangue , Doença Hepática Terminal/cirurgia , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Transplantados
2.
Clin Transplant ; 36(6): e14690, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35477939

RESUMO

Living donor liver transplantation was first developed to mitigate the limited access to deceased donor organs in Asia in the 1990s. This alternative liver transplantation method has become a widely practiced and established transplantation option for adult patients suffering with end-stage liver disease, and it has successfully helped address the shortage of deceased donors. The Society for the Advancement of Transplant Anesthesia and the Korean Society of Transplantation Anesthesiologists jointly reviewed published studies on the perioperative management of adult live liver donors undergoing donor hemi-hepatectomy. The goal of the review is to offer transplant anesthesiologists and critical care physicians a comprehensive overview of the perioperative management of adult live donors. We featured the current status, donor selection process, outcomes and complications, surgical procedure, anesthetic management, Enhanced Recovery After Surgery protocols, avoidance of blood transfusion, and considerations for emergency donation. Recent surgical advances, including laparoscopic donor hemi-hepatectomy and robotic laparoscopic donor surgery, are also addressed.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Adulto , Doença Hepática Terminal/cirurgia , Hepatectomia/métodos , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Coleta de Tecidos e Órgãos
3.
Surg Endosc ; 33(10): 3484-3493, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31144119

RESUMO

BACKGROUND: Ever since the introduction of laparoscopic surgery, researchers have been trying to add steerability to instruments to allow the surgeon to operate with better reachability and less tissue interaction force. Traditional solutions to introduce this often use a combination of springs, cables, pulleys, and guiding structures, resulting in instruments that cannot be properly cleaned and thus are very costly to manufacture and maintain. The aim of the study is to develop a novel affordable, sustainable, cableless, and fully steerable laparoscopic grasper, and to test its ease of assembly, disassembly, and use. METHODS: A set of requirements was defined to ensure that the instrument can be handled efficiently at the sterilization unit and in the operating room. Based on these, a multisteerable, cableless 5 mm laparoscopic instrument that operates based on shaft rotations was developed. To test its assembly and disassembly, ten participants were asked to fully dismantle the instrument and reassemble it a total of 60 times. In addition, ten medical students were asked to use the grasper in the ForceSense box-trainer system on a newly developed 3D pick-and-place task, to determine the control effort based on learning curves of steering errors, task time, instrument path length, and maximum tissue interaction force. RESULTS: All important design requirements were met. The recorded data indicates that ten engineering students were able to fully dismantle and reassemble the instrument shaft in 12 s (SD7) and 65 s (SD43) seconds at the sixth attempt. The learning-curve data indicates that three attempts were needed before the ten medical students started to use all steering functions. At the sixth attempt, on average only 1.25 (SD0.7) steering errors were made. The steepest slope in the learning curves for steering errors, path length, and task time was experienced during the first three attempts. In respect of the interaction force, no learning effect was observed. CONCLUSION: The multi-DOF (degree of freedom) cableless grasper can be assembled and disassembled for cleaning and sterilization within an acceptable time frame. The handle interface proved to be intuitive enough for novices to conduct a complex 3D pick-and-place task in a training setting.


Assuntos
Laparoscopia/instrumentação , Instrumentos Cirúrgicos , Desenho de Equipamento , Reutilização de Equipamento , Humanos , Laparoscopia/métodos , Teste de Materiais , Robótica , Análise e Desempenho de Tarefas
4.
Cytokine ; 106: 108-113, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29126764

RESUMO

Multiple sclerosis (MS) is a complex inflammatory, autoimmune disease of the central nervous system (CNS). The disease pathogenesis is not well defined yet. Cytokines have an important role in inflammation as characteristic feature of the disease. Janus kinase/signal transducers and activators of transcriptions (JAK/STAT) family promote cytokine-mediated cell activation. Failure in the JAK/STAT signaling pathway is associated with the pathological outcome in MS. In this study, we compared the expression levels of STAT5a and STAT6 genes in the blood of 50 relapsing-remitting MS (RR-MS) patients and 50 healthy controls by Taqman Quantitative Real-Time PCR in patients and healthy control group. We found that STAT5a expression was significantly down-regulated (p = .049), whereas STAT6 gene expression was significantly up-regulated (p = .046) in MS patients compared with controls. Moreover, there was significant correlation between the STAT6 gene expression and Kurtzke Expanded Disability Status Scale (EDSS) criterion. However, no significant correlation was demonstrated between the expression of STAT5a gene and clinical findings. Furthermore, there was not significant correlation between expression levels of STAT5a and STAT6 genes. Our findings suggest that STAT5a and STAT6 dysregulation may have a critical role in modification of immune responses leading to imbalance between Th2- and Th1-related cytokines. However, the mechanisms underlying it still remain to be elucidated. Future studies are needed to explore the role of STAT5a and STAT6 as prognostic biomarkers in research, design of experimental therapies or clinical settings of the MS.


Assuntos
Regulação da Expressão Gênica , Esclerose Múltipla/genética , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT6/genética , Proteínas Supressoras de Tumor/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT6/metabolismo , Estatísticas não Paramétricas , Proteínas Supressoras de Tumor/metabolismo
5.
Stat Methods Med Res ; 32(7): 1249-1266, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37194551

RESUMO

The goal of causal mediation analysis, often described within the potential outcomes framework, is to decompose the effect of an exposure on an outcome of interest along different causal pathways. Using the assumption of sequential ignorability to attain non-parametric identification, Imai et al. (2010) proposed a flexible approach to measuring mediation effects, focusing on parametric and semiparametric normal/Bernoulli models for the outcome and mediator. Less attention has been paid to the case where the outcome and/or mediator model are mixed-scale, ordinal, or otherwise fall outside the normal/Bernoulli setting. We develop a simple, but flexible, parametric modeling framework to accommodate the common situation where the responses are mixed continuous and binary, and, apply it to a zero-one inflated beta model for the outcome and mediator. Applying our proposed methods to the publicly-available JOBS II dataset, we (i) argue for the need for non-normal models, (ii) show how to estimate both average and quantile mediation effects for boundary-censored data, and (iii) show how to conduct a meaningful sensitivity analysis by introducing unidentified, scientifically meaningful, sensitivity parameters.


Assuntos
Análise de Mediação , Modelos Estatísticos , Causalidade , Motivação
6.
Curr Med Chem ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37916635

RESUMO

BACKGROUND: Although immunotherapies have greatly improved diffuse large B-cell lymphoma (DLBCL) prognosis, a proportion of patients remain to be relapsed or refractory. Therefore, the identification of novel therapeutic targets and drugs is urgently required. Inhibition of the bromodomain and extra-terminal (BET) proteins has been a promising therapeutic strategy for various haematologic cancers. CPI-0610 is a potent and selective BET inhibitor. The effects of CPI-0610 in DLBCL cells have not been reported yet. AIMS: The aim of this study was to assess the effects of CPI-0610 in DLBCL and its underlying mechanisms. METHODS: DLBCL cells were treated with CPI-0610, followed by measuring cell viability, cell cycle, apoptosis, autophagy, and specific cell signaling pathways. Moreover, immunodeficient mice were engrafted with SUDHL2 cells and then treated with CPI-0610 for analysis of tumor burden. We also analyzed the synergistic effect of CPI-0610 with histone deacetylase inhibitor suberoylanilide hydroxamic acid. RESULTS: The present study demonstrated that CPI-0610 displayed cell cytotoxicity by arresting the G1 cell cycle and inducing endogenous and exogenous apoptotic pathways. Additionally, CPI-0610 decreased BRD4 and c-Myc expressions and affected MAPK, JAK/STAT, and AKT signalling pathways in human DLBCL cells. An in vivo experiment exhibited that CPI-0610 decreased the primary tumour growth of the DLBCL xenograft model. Furthermore, the use of CPI-0610 in combination with suberoylanilide hydroxamic acid exhibited a specific synergistic effect in inducing apoptosis through the regulation of STAT3 and p38. CONCLUSION: Targeting BET may be an effective therapeutic strategy and potentiated by a combination with histone deacetylase inhibition in DLBCL.

7.
Front Hum Neurosci ; 16: 952602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118967

RESUMO

Background: Conventionally, transcranial direct current stimulation (tDCS) aims to focalize the current reaching the target region-of-interest (ROI). The focality can be quantified by the dose-target-determination-index (DTDI). Despite having a uniform tDCS setup, some individuals receive focal stimulation (high DTDI) while others show reduced focality ("non-focal"). The volume of cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) underlying each ROI govern the tDCS current distribution inside the brain, thereby regulating focality. Aim: To determine the regional volume parameters that differentiate the focal and non-focal groups. Methods: T1-weighted images of the brain from 300 age-sex matched adults were divided into three equal groups- (a) Young (20 ≤ × < 40 years), (b) Middle (40 ≤ × < 60 years), and (c) Older (60 ≤ × < 80 years). For each group, inter and intra-hemispheric montages with electrodes at (1) F3 and right supraorbital region (F3-RSO), and (2) CP5 and Cz (CP5-Cz) were simulated, targeting the left- Dorsolateral Prefrontal Cortex (DLPFC) and -Inferior Parietal Lobule (IPL), respectively. Both montages were simulated for two current doses (1 and 2 mA). For each individual head simulated for a tDCS configuration (montage and dose), the current density at each region-of-interest (ROI) and their DTDI were calculated. The individuals were categorized into two groups- (1) Focal (DTDI ≥ 0.75), and (2) Non-focal (DTDI < 0.75). The regional volume of CSF, GM, and WM of all the ROIs was determined. For each tDCS configuration and ROI, three 3-way analysis of variance was performed considering- (i) GM, (ii) WM, and (iii) CSF as the dependent variable (DV). The age group, sex, and focality group were the between-subject factors. For a given ROI, if any of the 3 DV's showed a significant main effect or interaction involving the focality group, then that ROI was classified as a "focal ROI." Results: Regional CSF was the principal determinant of focality. For interhemispheric F3-RSO montage, interaction effect (p < 0.05) of age and focality was observed at Left Caudate Nucleus, with the focal group exhibiting higher CSF volume. The CSF volume of focal ROI correlated positively (r ∼ 0.16, p < 0.05) with the current density at the target ROI (DLPFC). For intrahemispheric CP5-Cz montage, a significant (p < 0.05) main effect was observed at the left pre- and post-central gyrus, with the focal group showing lower CSF volume. The CSF volume correlated negatively (r ∼ -0.16, p < 0.05) with current density at left IPL. The results were consistent for both current doses. Conclusion: The CSF channels the flow of tDCS current between electrodes with focal ROIs acting like reservoirs of current. The position of focal ROI in the channel determines the stimulation intensity at the target ROI. For focal stimulation in interhemispheric F3-RSO, the proximity of focal ROI reserves the current density at the target ROI (DLPFC). In contrast, for intrahemispheric montage (CP5-Cz), the far-end location of focal ROI reduces the current density at the target (IPL).

8.
J Pers Med ; 11(9)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34575717

RESUMO

Background: In transcranial direct current stimulation (tDCS), the injected current becomes distributed across the brain areas. The objective is to stimulate the target region of interest (ROI) while minimizing the current in non-target ROIs (the 'focality' of tDCS). For this purpose, determining the appropriate current dose for an individual is difficult. Aim: To introduce a dose-target determination index (DTDI) to quantify the focality of tDCS and examine the dose-focality relationship in three different populations. Method: Here, we extended our previous toolbox i-SATA to the MNI reference space. After a tDCS montage is simulated for a current dose, the i-SATA(MNI) computes the average (over voxels) current density for every region in the brain. DTDI is the ratio of the average current density at the target ROI to the ROI with a maximum value (the peak region). Ideally, target ROI should be the peak region, so DTDI shall range from 0 to 1. The higher the value, the better the dose. We estimated the variation of DTDI within and across individuals using T1-weighted brain images of 45 males and females distributed equally across three age groups: (a) young adults (20 ≤ x ˂ 40 years), (b) mid adults (40 ≤ x ˂ 60 years), and (c) older adults (60 ≤ x ˂ 80 years). DTDI's were evaluated for the frontal montage with electrodes at F3 and the right supraorbital for three current doses of 1 mA, 2 mA, and 3 mA, with the target ROI at the left middle frontal gyrus. Result: As the dose is incremented, DTDI may show (a) increase, (b) decrease, and (c) no change across the individuals depending on the relationship (nonlinear or linear) between the injected tDCS current and the distribution of current density in the target ROI. The nonlinearity is predominant in older adults with a decrease in focality. The decline is stronger in males. Higher current dose at older age can enhance the focality of stimulation. Conclusion: DTDI provides information on which tDCS current dose will optimize the focality of stimulation. The recommended DTDI dose should be prioritized based on the age (>40 years) and sex (especially for males) of an individual. The toolbox i-SATA(MNI) is freely available.

9.
Am J Transl Res ; 11(8): 5212-5226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497235

RESUMO

Macrophage polarization determines the transition from the inflammation phase to the inflammation resolution phase after myocardial infarction (MI). The aim of the present study was to investigate whether resveratrol (RSV) could inhibit the inflammatory mediators associated with the regulation of macrophage phenotypes and functions in MI mice. We initially discovered that RSV significantly improved cardiac function and suppressed the expression of fibrosis markers, such as collagen-I, collagen-III, and fibronectin, and pro-inflammatory cytokines, including interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). RSV inhibited the expression of M1-like macrophage-related biomarkers (e.g., TNF-α and MCP-1) when bone marrow-derived macrophages (BMDMs) were stimulated with lipopolysaccharide (LPS) and interferon-γ (INF-γ). In contrast, it upregulated M2-like macrophage-related biomarkers (e.g., CD163 and Arg-1) when BMDMs were stimulated with interleukin-4 (IL-4) and interleukin-10 (IL-10). In addition, we found that RSV promoted M2-like macrophage polarization under anoxic conditions, which could be related to JAK2-SATA3 phosphorylation. In summary, RSV might promote anti-inflammatory M2-like polarization of macrophages after MI to improve cardiac function via the regulation of JAK2-SATA3 phosphorylation.

10.
Cancer Biother Radiopharm ; 33(8): 349-355, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30010404

RESUMO

Radioimmunotherapy offers an effective way to direct ionizing radiation to cancer cells through attachment of radionuclides to antibodies while limiting negative effects of off-target irradiation. This, however, requires effective facile methods for attachment of therapeutic radionuclides onto antibodies. Herein, the authors report their efforts in evaluating N-succinimidyl S-acetylthioacetate (SATA), a commercially available reagent, for use as a bifunctional chelating agent (BCA) to attach 188Rhenium (188Re) onto h8C3, a humanized IgG antibody that can effectively target extracellular melanin present in malignant melanoma. Micro single photon emission computer tomography/computer tomography was used to determine an effective timeline for antibody uptake in B16-F10 tumor bearing C57BL6 mice guiding the selection of 188Re with its 16.9 h physical half-life. Radio instant thin layer chromatography coupled with radio high-performance liquid chromatography was used to assess radioisotope incorporation, as well as stability during the labeling process for SATA conjugated h8C3. It was determined that despite the relatively mild conditions used, incorporation of the SATA conjugate resulted in antibody instability during labeling requiring a different BCA to facilitate rhenium incorporation onto the antibodies.


Assuntos
Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais/química , Radioisótopos/química , Rênio/química , Succinimidas/química , Sulfetos/química , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Quelantes/química , Feminino , Humanos , Ligantes , Melanoma/radioterapia , Camundongos , Camundongos Endogâmicos C57BL , Radioimunoterapia/métodos , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/química , Rênio/uso terapêutico
11.
J Control Release ; 241: 57-67, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27620073

RESUMO

Parasite proteins exported to the surface of Plasmodium falciparum-parasitized red blood cells (pRBCs) have a major role in severe malaria clinical manifestation, where pRBC cytoadhesion and rosetting processes have been strongly linked with microvascular sequestration while avoiding both spleen filtration and immune surveillance. The parasite-derived and pRBC surface-exposed PfEMP1 protein has been identified as one of the responsible elements for rosetting and, therefore, considered as a promising vaccine candidate for the generation of rosette-disrupting antibodies against severe malaria. However, the potential role of anti-rosetting antibodies as targeting molecules for the functionalization of antimalarial drug-loaded nanovectors has never been studied. Our manuscript presents a proof-of-concept study where the activity of an immunoliposomal vehicle with a dual performance capable of specifically recognizing and disrupting rosettes while simultaneously eliminating those pRBCs forming them has been assayed in vitro. A polyclonal antibody against the NTS-DBL1α N-terminal domain of a rosetting PfEMP1 variant has been selected as targeting molecule and lumefantrine as the antimalarial payload. After 30min incubation with 2µM encapsulated drug, a 70% growth inhibition for all parasitic forms in culture (IC50: 414nM) and a reduction in ca. 60% of those pRBCs with a rosetting phenotype (IC50: 747nM) were achieved. This immunoliposomal approach represents an innovative combination therapy for the improvement of severe malaria therapeutics having a broader spectrum of activity than either anti-rosetting antibodies or free drugs on their own.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Antimaláricos/administração & dosagem , Eritrócitos/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/imunologia , Formação de Roseta , Antimaláricos/farmacologia , Células Cultivadas , Humanos , Lipossomos , Plasmodium falciparum/imunologia
12.
J Control Release ; 210: 217-29, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26008752

RESUMO

One of the most important factors behind resistance evolution in malaria is the failure to deliver sufficiently high amounts of drugs to early stages of Plasmodium-infected red blood cells (pRBCs). Despite having been considered for decades as a promising approach, the delivery of antimalarials encapsulated in immunoliposomes targeted to pRBCs has not progressed towards clinical applications, whereas in vitro assays rarely reach drug efficacy improvements above 10-fold. Here we show that encapsulation efficiencies reaching >96% are achieved for the weak basic drugs chloroquine (CQ) and primaquine using the pH gradient loading method in liposomes containing neutral saturated phospholipids. Targeting antibodies are best conjugated through their primary amino groups, adjusting chemical crosslinker concentration to retain significant antigen recognition. Antigens from non-parasitized RBCs have also been considered as targets for the delivery to the cell of drugs not affecting the erythrocytic metabolism. Using this strategy, we have achieved unprecedented complete nanocarrier targeting to early intraerythrocytic stages of the malaria parasite for which there is a lack of specific extracellular molecular tags. Immunoliposomes studded with monoclonal antibodies raised against the erythrocyte surface protein glycophorin A were capable of targeting 100% RBCs and pRBCs at the low concentration of 0.5µM total lipid in the culture, with >95% of added liposomes retained on cell surfaces. When exposed for only 15min to Plasmodium falciparum in vitro cultures of early stages, free CQ had no significant effect on the viability of the parasite up to 200nM, whereas immunoliposomal 50nM CQ completely arrested its growth. In vivo assays in mice showed that immunoliposomes cleared the pathogen below detectable levels at a CQ dose of 0.5mg/kg, whereas free CQ administered at 1.75mg/kg was, at most, 40-fold less efficient. Our data suggest that this significant improvement is in part due to a prophylactic effect of CQ found by the pathogen in its host cell right at the very moment of invasion.


Assuntos
Antimaláricos/administração & dosagem , Cloroquina/administração & dosagem , Primaquina/administração & dosagem , Animais , Anticorpos , Antígenos de Protozoários/imunologia , Proteínas de Transporte/imunologia , Sistemas de Liberação de Medicamentos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Feminino , Humanos , Lipossomos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/prevenção & controle , Proteínas de Membrana , Camundongos Transgênicos , Oligopeptídeos/imunologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/imunologia
13.
Adv Drug Deliv Rev ; 65(8): 1098-111, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23123291

RESUMO

With the technological development of positron emission tomography (PET) and the advent of novel antibody-directed drug delivery systems, longer-lived positron-emitting radionuclides are moving to the forefront to take important roles in tracking the distribution of biotherapeutics such as antibodies, and for monitoring biological processes and responses. Longer half-life radionuclides possess advantages of convenient on-site preparation procedures for both clinical and non-clinical applications. The suitability of the long half-life radionuclides for imaging intact monoclonal antibodies (mAbs) and their respective fragments, which have inherently long biological half-lives, has attracted increased interest in recent years. In this review, we provide a survey of the recent literature as it applies to the development of nine-selected longer-lived positron emitters with half-lives of 9-140h (e.g., (124)I, (64)Cu, (86)Y and (89)Zr), and describe the biological behaviors of radionuclide-labeled mAbs with respect to distribution and targeting characteristics, potential toxicities, biological applications, and clinical translation potentials.


Assuntos
Anticorpos Monoclonais , Radioisótopos , Animais , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/uso terapêutico , Humanos , Tomografia por Emissão de Pósitrons , Radioisótopos/farmacocinética , Radioisótopos/uso terapêutico
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