Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
1.
PLoS Pathog ; 18(3): e1010309, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35316298

RESUMO

The eggs of the parasitic blood fluke, Schistosoma, are the main drivers of the chronic pathologies associated with schistosomiasis, a disease of poverty afflicting approximately 220 million people worldwide. Eggs laid by Schistosoma mansoni in the bloodstream of the host are encapsulated by vascular endothelial cells (VECs), the first step in the migration of the egg from the blood stream into the lumen of the gut and eventual exit from the body. The biomechanics associated with encapsulation and extravasation of the egg are poorly understood. We demonstrate that S. mansoni eggs induce VECs to form two types of membrane extensions during encapsulation; filopodia that probe eggshell surfaces and intercellular nanotubes that presumably facilitate VEC communication. Encapsulation efficiency, the number of filopodia and intercellular nanotubes, and the length of these structures depend on the egg's vitality and, to a lesser degree, its maturation state. During encapsulation, live eggs induce VEC contractility and membranous structures formation in a Rho/ROCK pathway-dependent manner. Using elastic hydrogels embedded with fluorescent microbeads as substrates to culture VECs, live eggs induce VECs to exert significantly greater contractile forces during encapsulation than dead eggs, which leads to 3D deformations on both the VEC monolayer and the flexible substrate underneath. These significant mechanical deformations cause the VEC monolayer tension to fluctuate with the eventual rupture of VEC junctions, thus facilitating egg transit out of the blood vessel. Overall, our data on the mechanical interplay between host VECs and the schistosome egg improve our understanding of how this parasite manipulates its immediate environment to maintain disease transmission.


Assuntos
Esquistossomose mansoni , Esquistossomose , Animais , Células Endoteliais , Humanos , Óvulo , Schistosoma mansoni , Esquistossomose mansoni/parasitologia
2.
Pediatr Transplant ; 26(4): e14228, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35037342

RESUMO

BACKGROUND: LT is a treatment option for MMA patients, but renal function impairment is one of the long-term concerns. The aim of this study was to evaluate the outcomes of early LT in these patients. METHODS: A total of 11 MMA mut-type patients (including 10 mut0 cases and 1 mut-case) who received LT in our institute were reviewed. Their metabolic profiles were compared between the pre/post-transplant periods. Their immunosuppressant and renal function changes after transplantation were assessed. RESULTS: After a mean follow-up of 97.5 ± 38.4 months, there were two deaths, and the actual survival rate was 81.8%. Their metabolic profiles had improved (mean blood ammonia level 366.8 ± 105.5 vs. 53.1 ± 17.4 µg/dl, p < .001; C3/C2 ratio 2.68 ± 0.87 vs. 0.73 ± 0.22, p = .003; mean urine MMA level 920.5 ± 376.6 vs. 196.2 ± 85.4, p = .067), and hospital stays were decreased (78.8 ± 74.5 vs. 7.4 ± 7.0 days/year, p = .009) after transplantation. The mean age at transplant was 1.81 ± 2.02 years old, and nine of these patients received LT before the age of 1.5 years old (early LT). Under prospective immunosuppressant dose reduction, three of these early LT patients discontinued the drug and were sustained for more than 5 years. Most of the patients had a preserved renal function, and no patient is currently on dialysis. CONCLUSIONS: In addition to the improvement in the metabolic parameters, early LT in MMA patients may allow for a dose reduction of the immunosuppressant, and the patient's renal function could be preserved in the long term.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Transplante de Fígado , Erros Inatos do Metabolismo dos Aminoácidos/cirurgia , Criança , Pré-Escolar , Humanos , Imunossupressores/uso terapêutico , Lactente , Transplante de Fígado/efeitos adversos , Estudos Prospectivos
3.
Proc Natl Acad Sci U S A ; 115(1): 133-138, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29255056

RESUMO

Leukocyte transmigration across vessel walls is a critical step in the innate immune response. Upon their activation and firm adhesion to vascular endothelial cells (VECs), leukocytes preferentially extravasate across junctional gaps in the endothelial monolayer (paracellular diapedesis). It has been hypothesized that VECs facilitate paracellular diapedesis by opening their cell-cell junctions in response to the presence of an adhering leukocyte. However, it is unclear how leukocytes interact mechanically with VECs to open the VEC junctions and migrate across the endothelium. In this study, we measured the spatial and temporal evolution of the 3D traction stresses generated by the leukocytes and VECs to elucidate the sequence of mechanical events involved in paracellular diapedesis. Our measurements suggest that the contractile stresses exerted by the leukocytes and the VECs can separately perturb the junctional tensions of VECs to result in the opening of gaps before the initiation of leukocyte transmigration. Decoupling the stresses exerted by the transmigrating leukocytes and the VECs reveals that the leukocytes actively contract the VECs to open a junctional gap and then push themselves across the gap by generating strong stresses that push into the matrix. In addition, we found that diapedesis is facilitated when the tension fluctuations in the VEC monolayer were increased by proinflammatory thrombin treatment. Our findings demonstrate that diapedesis can be mechanically regulated by the transmigrating leukocytes and by proinflammatory signals that increase VEC contractility.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Junções Intercelulares/metabolismo , Leucócitos/metabolismo , Modelos Biológicos , Migração Transendotelial e Transepitelial/fisiologia , Células HL-60 , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Leucócitos/citologia
4.
Pediatr Hematol Oncol ; 38(4): 385-390, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33641599

RESUMO

We herein report the case of a girl with PRETEXT III hepatoblastoma (HB) developing recurrent lung metastases despite multiple chemotherapy regimens, aggressive tumor excision, multiple lung metastasectomies, and autologous peripheral blood stem cell transplantation. High tumor mutation burden (TMB) was identified through targeted next-generation sequencing, and pembrolizumab was administered post-operatively as a last resort. A complete and sustained response to the immune checkpoint inhibitor was achieved for 22 months. Although the majority of HB have a low TMB, immune checkpoint inhibitor therapy may be useful for patients with refractory HBs with a high TMB.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Hepatoblastoma/terapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/secundário , Pré-Escolar , Feminino , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Transplante de Células-Tronco , Resultado do Tratamento
5.
World J Surg ; 44(2): 371-377, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31531721

RESUMO

BACKGROUND: Thyroidectomy transoral endoscopic thyroidectomy vestibular approach (TOETVA) is a safe and cosmetically appealing alternative for well-selected patients undergoing thyroidectomy. However, during TOETVA, placement of the two lateral trocars and/or manipulation of the surgical instruments through the trocars may potentially injure and/or compress the mental nerve (MN) because the actual location of the nerve foramen may vary among individuals. The MN injury rate was reported to be as high as 75% in the initial period of robotic-assisted TOETVA. To reduce the potential risk of MN injury, we implemented a three-dimensional printing technology to develop a safety device for TOETVA. METHODS: The patient-specific safety device (PSSD) was a brace with an exact fit to the lower teeth and two safety markers on each side to indicate the location of the mental foramen. For patient in whom the brace would not be applicable, a 3D mandibular model was printed as a PSSD instead. We analyzed 66 patients undergoing TOETVA at our institution from March 2017 to March 2019. The preoperative details and complication profiles were also analyzed. RESULTS: With incorporation of the PSSD into our TOETVA procedure, there have been no cases of MN injury. CONCLUSIONS: Our own TOETVA series has demonstrated that the implementation of the PSSD has been successful in preoperatively identifying and preventing the potential risk of MN injury. Although the additional requirements of preoperative CT and time for fabricating the device impose limitations, the influence of the PSSD in TOETVA is positive.


Assuntos
Traumatismos do Nervo Mandibular/prevenção & controle , Impressão Tridimensional , Equipamentos de Proteção , Tireoidectomia/métodos , Adolescente , Adulto , Idoso , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tireoidectomia/efeitos adversos , Tireoidectomia/instrumentação , Adulto Jovem
6.
Biophys J ; 117(1): 111-128, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31103228

RESUMO

Many biological processes involve the collective generation and transmission of mechanical stresses across cell monolayers. In these processes, the monolayer undergoes lateral deformation and bending because of the tangential and normal components of the cell-generated stresses. Monolayer stress microscopy (MSM) methods have been developed to measure the intracellular stress distribution in cell monolayers. However, current methods assume plane monolayer geometry and neglect the contribution of bending to the intracellular stresses. This work introduces a three-dimensional (3D) MSM method that calculates monolayer stress from measurements of the 3D traction stresses exerted by the cells on a flexible substrate. The calculation is carried out by imposing equilibrium of forces and moments in the monolayer, subject to external loads given by the 3D traction stresses. The equilibrium equations are solved numerically, and the algorithm is validated for synthetic loads with known analytical solutions. We present 3D-MSM measurements of monolayer stress in micropatterned islands of endothelial cells of different sizes and shapes. These data indicate that intracellular stresses caused by lateral deformation emerge collectively over long distances; they increase with the distance from the island edge until they reach a constant value that is independent of island size. On the other hand, bending-induced intracellular stresses are more concentrated spatially and remain confined to within one to two cell lengths of bending sites. The magnitude of these bending stresses is highest at the edges of the cell islands, where they can exceed the intracellular stresses caused by lateral deformations. Our data from nonpatterned monolayers suggests that biomechanical perturbations far away from monolayer edges also cause significant localized alterations in bending tension. The localized effect of bending-induced stresses may be important in processes like cellular extravasation, which are accompanied by significant normal deflections of a cell monolayer (i.e., the endothelium) and require localized changes in monolayer permeability.


Assuntos
Imageamento Tridimensional/métodos , Estresse Mecânico , Forma Celular , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Microscopia de Fluorescência/métodos
7.
Proc Natl Acad Sci U S A ; 113(41): 11525-11530, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671657

RESUMO

The focal nature of atherosclerotic lesions suggests an important role of local hemodynamic environment. Recent studies have demonstrated significant roles of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) in mediating mechanotransduction and vascular homeostasis. The objective of this study is to investigate the functional role of YAP/TAZ in the flow regulation of atheroprone endothelial phenotypes and the consequential development of atherosclerotic lesions. We found that exposure of cultured endothelial cells (ECs) to the atheroprone disturbed flow resulted in YAP/TAZ activation and translocation into EC nucleus to up-regulate the target genes, including cysteine-rich angiogenic inducer 61 (CYR61), connective tissue growth factor (CTGF), and ankyrin repeat domain 1 (ANKRD1). In contrast, the athero-protective laminar flow suppressed YAP/TAZ activities. En face analysis of mouse arteries demonstrated an increased nuclear localization of YAP/TAZ and elevated levels of the target genes in the endothelium in atheroprone areas compared with athero-protective areas. YAP/TAZ knockdown significantly attenuated the disturbed flow induction of EC proliferative and proinflammatory phenotypes, whereas overexpression of constitutively active YAP was sufficient to promote EC proliferation and inflammation. In addition, treatment with statin, an antiatherosclerotic drug, inhibited YAP/TAZ activities to diminish the disturbed flow-induced proliferation and inflammation. In vivo blockade of YAP/TAZ translation by morpholino oligos significantly reduced endothelial inflammation and the size of atherosclerotic lesions. Our results demonstrate a critical role of the activation of YAP/TAZ by disturbed flow in promoting atheroprone phenotypes and atherosclerotic lesion development. Therefore, inhibition of YAP/TAZ activation is a promising athero-protective therapeutic strategy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Reologia , Animais , Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Artéria Carótida Primitiva/patologia , Ciclo Celular , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Proteína Rica em Cisteína 61/metabolismo , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inflamação/patologia , Camundongos , Proteínas Musculares/metabolismo , Proteínas Nucleares/metabolismo , Fenótipo , Proteínas Repressoras/metabolismo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
8.
Arterioscler Thromb Vasc Biol ; 34(7): 1437-45, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24855060

RESUMO

OBJECTIVE: The site-specificity of endothelial phenotype is attributable to the local hemodynamic forces. The flow regulation of microRNAs in endothelial cells (ECs) plays a significant role in vascular homeostasis and diseases. The objective of this study was to elucidate the molecular mechanism by which the pulsatile shear flow-induced microRNA-23b (miR-23b) exerts antiproliferative effects on ECs. APPROACH AND RESULTS: We used a combination of a cell perfusion system and experimental animals to examine the flow regulation of miR-23b in modulating EC proliferation. Our results demonstrated that pulsatile shear flow induces the transcription factor Krüppel-like factor 2 to promote miR-23b biosynthesis; the increase in miR-23b then represses cyclin H to impair the activity and integrity of cyclin-dependent kinase-activating kinase (CAK) complex. The inhibitory effect of miR-23b on CAK exerts dual actions to suppress cell cycle progression, and reduce basal transcription by deactivating RNA polymerase II. Whereas pulsatile shear flow regulates the miR-23b/CAK pathway to exert antiproliferative effects on ECs, oscillatory shear flow has little effect on the miR-23b/CAK pathway and hence does not cause EC growth arrest. Such flow pattern-dependent phenomena are validated with an in vivo model on rat carotid artery: the flow disturbance induced by partial carotid ligation led to a lower expression of miR-23b and a higher EC proliferation in comparison with the pulsatile flow regions of the unligated vessels. Local delivery of miR-23b mitigated the proliferative EC phenotype in partially ligated vessels. CONCLUSIONS: Our findings unveil a novel mechanism by which hemodynamic forces modulate EC proliferative phenotype through the miR-23b/CAK pathway.


Assuntos
Doenças das Artérias Carótidas/enzimologia , Proliferação de Células , Ciclina H/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Células Endoteliais/enzimologia , Células Endoteliais da Veia Umbilical Humana/enzimologia , MicroRNAs/metabolismo , Transcrição Gênica , Animais , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/fisiopatologia , Pontos de Checagem do Ciclo Celular , Células Cultivadas , Ciclina H/genética , Quinases Ciclina-Dependentes/genética , Modelos Animais de Doenças , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Mecanotransdução Celular , MicroRNAs/genética , Perfusão , Fenótipo , Fluxo Pulsátil , Interferência de RNA , RNA Polimerase II/metabolismo , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Estresse Mecânico , Fatores de Tempo , Transfecção , Quinase Ativadora de Quinase Dependente de Ciclina
9.
Trends Parasitol ; 40(2): 164-175, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38172015

RESUMO

The dissemination of protozoan and metazoan parasites through host tissues is hindered by cellular barriers, dense extracellular matrices, and fluid forces in the bloodstream. To overcome these diverse biophysical impediments, parasites implement versatile migratory strategies. Parasite-exerted mechanical forces and upregulation of the host's cellular contractile machinery are the motors for these strategies, and these are comparably better characterized for protozoa than for helminths. Using the examples of the protozoans, Toxoplasma gondii and Plasmodium, and the metazoan, Schistosoma mansoni, we highlight how quantitative tools such as traction force and reflection interference contrast microscopies have improved our understanding of how parasites alter host mechanobiology to promote their migration.


Assuntos
Helmintos , Parasitos , Plasmodium , Toxoplasma , Animais , Fenômenos Biomecânicos , Helmintos/fisiologia , Toxoplasma/fisiologia
10.
J Lipid Res ; 54(2): 365-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23197320

RESUMO

Cellular cholesterol is known to be under homeostatic control in nonsteroidogenic cells, and this intrigued us to understand how such control works in steroidogenic cells that additionally use cholesterol for steroid hormone synthesis. We employed primary culture of rat ovarian granulosa cells to study how steroidogenic cells adapt to acquire sufficient cholesterol to meet the demand of active steroidogenesis under the stimulation of gonadotropin follicle-stimulating hormone (FSH) and cytokine transforming growth factor (TGF)ß1. We found that TGFß1 potentiated FSH to upregulate scavenger receptor class B member I (SR-BI) and LDL receptor (LDLR), both functional in uptaking cholesterol as hHDL(3) and hLDL supplementation enhanced progesterone production, and the effect of each lipoprotein was completely or partially blocked by SR-BI selective inhibitor BLT-1. Uptaken cholesterol could also be stored in lipid droplets. Importantly, LDLR and SR-BI responded to sterol with different sensitivity. Giving cells lipoproteins or 25-hydroxycholesterol downregulated Ldlr but not Scarb1; Scarb1 was ultimately downregulated by excessive sterol accumulation under 25-hydroxycholesterol and aminoglutethimide (inhibitor of steroidogenesis) cotreatment. Furthermore, transcription factors sterol regulatory element-binding protein (SREBP)-2 and liver receptor homolog (LRH)-1 crucially mediated Ldlr and Scarb1 differential response to sterol challenge. This study reveals that ovarian granulosa cells retain the cholesterol homeostatic control machinery like nonsteroidogenic cells, although during active steroidogenesis, they utilize SR-BI to evade such feedback control.


Assuntos
Antígenos CD36/metabolismo , Colesterol/metabolismo , Células da Granulosa/metabolismo , Homeostase , Esteroides/biossíntese , Animais , Feminino , Hormônio Foliculoestimulante/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/citologia , Células da Granulosa/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de LDL/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Fator de Crescimento Transformador beta1/farmacologia
11.
Plast Reconstr Surg Glob Open ; 11(1): e4792, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36691601

RESUMO

In the era of the coronavirus disease 2019 (COVID-19) pandemic, surgeons and medical staff are often at a high risk of infection in the operating room, especially when the patient is spontaneously breathing. In this study, we examined the minimum requirements for personal protective equipment with double surgical masks to potentially reduce unnecessary waste of supplies. Methods: Two mannequins were each connected to a test lung machine simulating a surgeon and patient with spontaneous breathing. An aerosol generator containing severe acute respiratory syndrome coronavirus 2 virion particle substitutes was connected to the patient mannequin. The sampling points for the target molecules were set at different distances from the patient mannequin and sent for multiplex quantitative polymerase chain reaction analysis. Three clinical scenarios were designed, which differed in terms of the operating room pressure and whether a fabric curtain barrier was installed between the mannequins. Results: Analysis of the multiplex quantitative polymerase chain reaction results showed that the cycle threshold (Ct) value of the target molecule increased as the distance from the aerosol source increased. In the negative-pressure operating room, the Ct values were significantly increased at all sample points compared with the normal pressure room setting. The Ct value sampled at the surgeon mannequin wearing double face masks was significantly increased when a cloth curtain barrier was set up between the two mannequins. Conclusion: Double surgical masks provide elementary surgeon protection against COVID-19 in a negative pressure operating room, with a physical barrier in place between the surgeon and patient who is spontaneously breathing during local anesthesia or sedated surgery.

12.
J Biomed Sci ; 19(1): 79, 2012 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-22931291

RESUMO

Atherosclerosis is commonly appreciated to represent a chronic inflammatory response of the vascular wall, and its complications cause high mortality in patients. Angioplasty with stent replacement is commonly performed in patients with atherosclerotic disease. However, the restenosis usually has a high incidence rate in angioplasty patients. Although the pathophysiological mechanisms underlying atherosclerosis and restenosis have been well established, new signaling molecules that control the progress of these pathologies have continuously been discovered. MicroRNAs (miRs) have recently emerged as a novel class of gene regulators that work via transcriptional degradation and translational inhibition or activation. Over 30% of genes in the cell can be directly regulated by miRs. Thus, miRs are recognized as crucial regulators in normal development, physiology and pathogenesis. Alterations of miR expression profiles have been revealed in diverse vascular diseases. A variety of functions of vascular cells, such as cell differentiation, contraction, migration, proliferation and inflammation that are involved in angiogenesis, neointimal formation and lipid metabolism underlying various vascular diseases, have been found to be regulated by miRs. This review summarizes current research progress and knowledge on the roles of miRs in regulating vascular cell function in atherosclerosis and restenosis. These discoveries are expected to present opportunities for clinical diagnostic and therapeutic approaches in vascular diseases resulting from atherosclerosis and restenosis.


Assuntos
Aterosclerose/genética , Reestenose Coronária/genética , MicroRNAs/metabolismo , Aterosclerose/patologia , Diferenciação Celular , Reestenose Coronária/patologia , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Neovascularização Patológica
14.
J Chin Med Assoc ; 85(2): 259-262, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34974508

RESUMO

Total implantable venous access port (TIVAP) by cephalic vein cutdown (CVCD) is one of the first procedures surgery residents can be performed independently under supervision. There is currently a lack of affordable simulators for teaching and assessing TIVAP competency to improve patient safety. A panel of 10 experts divided the TIVAP by CVCD procedure into 9 steps. A homemade, low-cost ($3 USD) simulator was then designed for practicing standardized procedural steps in the context of a simulation-based mastery learning course. Residents were given a simulator for at-home practice and completed a survey evaluating the simulator and their learning experience. Twenty-eight first-year surgery residents participated in the course and completed the survey. They were highly satisfied with the simulator (mean score = 8.7 of 10) and generally agreed with its anatomical appearance and functional fidelity. They also appreciated the educational value of using this simulator to learn and practice basic techniques and procedural steps. Our novel, homemade simulator of CVCD TIVAP implantation is a cost-effective way of achieving procedural competence of a basic operation for inexperienced surgery residents. We envision the same principle can be applied to other procedures to enhance resident education.


Assuntos
Cateterismo Venoso Central/normas , Competência Clínica , Treinamento por Simulação , Dispositivos de Acesso Vascular , Venostomia/educação , Humanos , Inquéritos e Questionários
15.
Adv Sci (Weinh) ; 9(20): e2201481, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35508805

RESUMO

Red blood cells (RBCs) are cleared from the circulation when they become damaged or display aging signals targeted by macrophages. This process occurs mainly in the spleen, where blood flows through submicrometric constrictions called inter-endothelial slits (IES), subjecting RBCs to large-amplitude deformations. In this work, RBCs are circulated through microfluidic devices containing microchannels that replicate the IES. The cyclic mechanical stresses experienced by the cells affect their biophysical properties and molecular composition, accelerating cell aging. Specifically, RBCs quickly transition to a more spherical, less deformable phenotype that hinders microchannel passage, causing hemolysis. This transition is associated with the release of membrane vesicles, which self-extinguishes as the spacing between membrane-cytoskeleton linkers becomes tighter. Proteomics analysis of the mechanically aged RBCs reveals significant losses of essential proteins involved in antioxidant protection, gas transport, and cell metabolism. Finally, it is shown that these changes make mechanically aged RBCs more susceptible to macrophage phagocytosis. These results provide a comprehensive model explaining how physical stress induces RBC clearance in the spleen. The data also suggest new biomarkers of early "hemodamage" and inflammation preceding hemolysis in RBCs subjected to mechanical stress.


Assuntos
Membrana Eritrocítica , Hemólise , Membrana Eritrocítica/metabolismo , Humanos , Macrófagos , Fagocitose , Estresse Mecânico
16.
Biomedicines ; 10(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35203693

RESUMO

The safe establishment of pneumoperitoneum is a critical step in all laparoscopic surgeries. A closed pneumoperitoneum is usually obtained by inserting a Veress needle into the peritoneal cavity. However, there is no definite measure to visually confirm the position of the Veress needle tip inside the peritoneal cavity. This study aimed to describe a method of real-time visual detection of peritoneal placement of the Veress needle using an incorporated optical coherence tomography (OCT) probe in a porcine model. A 14-gauge Veress needle was incorporated with a miniature fiber probe to puncture the piglet's abdominal wall into the peritoneal cavity. A total of 80 peritoneal punctures were attempted in four piglets. For each puncture, continuous two-dimensional OCT images of the abdominal wall were acquired for real-time visual detection of the needle placement into the peritoneal cavity. Characteristic OCT image patterns could be observed during the puncturing process, especially a deep V-shaped concave pattern before the peritoneum puncture, which was a crucial feature. A statistical difference in the OCT signal standard deviation value also indicated the differentiability of images between the peritoneum and extra-peritoneal tissue layers. A success rate of 97.5% could be achieved with the guidance of the OCT images. OCT images translate the blind closed technique of peritoneal access into a visualized procedure, thus improving peritoneal access safety.

17.
Cancers (Basel) ; 14(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35159093

RESUMO

Hepatocellular carcinoma (HCC) is the most common cancer in end-stage renal disease (ESRD) patients in Taiwan. Whether statin therapy associated with the HCC risk in hyperlipidemic patients with chronic kidney disease (CKD) and ESRD is unclear. Using population-based insurance claim data from Taiwan, we identified from hyperlipidemic patients taking statins or not (677,364 versus 867,707) in 1999-2015. Among them, three pairs of propensity score matched statin and non-statin cohorts were established by renal function: 413,867 pairs with normal renal function (NRF), 46,851 pairs with CKD and 6372 pairs with ESRD. Incidence rates of HCC were compared, by the end of 2016, between statin and non-statin cohorts, between hydrophilic statins (HS) and lipophilic statins (LS) users, and between statin-ezetimibe combination therapy (SECT) and statin monotherapy (SM) users. The HCC incidence increased progressively from NRF to CKD and ESRD groups, was lower in the statin cohort than in the non-statin cohort, with the differences of incidence per 10,000 person-years increased from (7.77 vs. 21.4) in NRF group to (15.8 vs. 37.1) in CKD group to (19.1 vs. 47.8) in ESRD group. The incidence increased with age, but the Cox method estimated hazard ratios showed a greater statin effectiveness in older patients. Among statin users, the HCC incidence was lower in HS users than in LS users, and lower in SECT users than in SM users, but the difference was significant only in the NRF group. Hyperlipidemic patients with CKD and ESRD receiving statins are at reduced HCC risks; the treatment effectiveness is superior for HS users than for LS users, and for SECT users than for SM users, but not significant.

18.
J Pediatr Surg ; 57(7): 1210-1214, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35400491

RESUMO

BACKGROUND: Using "large-for-size" liver graft, graft-to-recipient weight ratio (GRWR) ≥4%, has been debated in pediatric liver transplantation due to possible graft compartment after abdomen closure. Meticulous preoperative evaluation with three-dimensional (3D) techniques may prevent these problems. This study compared the safety of large-for-size grafts in pediatric living donor liver transplantation (PLDLT) during the eras with or without 3D planning. METHODS: We defined the 3D era was after November 2017 due to our first implication of 3D printing for surgical planning and subsequently developing a 3D simulation implanting model. From November 2004 to July 2021, we enrolled 30 PLDLT patients with body weight (BW) < 10 kg and categorized them into conventional group: GRWR ≥4% before the 3D era (n = 9), 3D group: GRWR ≥4% in the 3D era (n = 8), and control group: GRWR <4% (n = 13). We followed and compared their clinical outcomes. RESULTS: The 3D group had the lowest BW and the highest graft volume reduction rate, with all receiving modified left lateral segments (LLS), such as reduced LLS (n = 2), hyperreduced LLS (n = 5), and segment 2 monosegment (n = 1). Overall postoperative complications were similar in conventional and control groups but significantly lower in the 3D group (OR 0.06, 95% CI 0.006-0.70, p = 0.025). However, all groups had similar graft and patient survival at 1, 2, and 4 years. CONCLUSION: Advanced preoperative 3D planning can decrease post-transplant complications and increase the safety of large-for-size grafts in PLDLT. LEVEL OF EVIDENCE: Type of study: Retrospective comparative study; Evidence level: Level III.


Assuntos
Transplante de Fígado , Doadores Vivos , Criança , Sobrevivência de Enxerto , Humanos , Fígado/cirurgia , Transplante de Fígado/métodos , Tamanho do Órgão , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento
19.
Biomedicines ; 10(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35740313

RESUMO

To investigate the effects of hydroxychloroquine (HCQ) drug use on the risk of pulmonary vascular disease (PVD) in an interstitial lung disease cohort (ILD cohort, ILD+ virus infection), we retrospectively enrolled the ILD cohort with HCQ (HCQ users, N = 4703) and the ILD cohort without HCQ (non-HCQ users, N = 4703) by time-dependence after propensity score matching. Cox models were used to analyze the risk of PVD. We calculated the adjusted hazard ratios (aHRs) and their 95% confidence intervals (CIs) for PVD after adjusting for sex, age, comorbidities, index date and immunosuppressants, such as steroids, etc. Compared with the HCQ nonusers, in HCQ users, the aHRs (95% CIs) for PVD were (2.24 (1.42, 3.54)), and the women's aHRs for PVD were (2.54, (1.49, 4.35)). The aHRs based on the days of HCQ use for PVD of 28−30 days, 31−120 days, and >120 days were (1.27 (0.81, 1.99)), (3.00 (1.81, 4.87)) and (3.83 (2.46, 5.97)), respectively. The medium or long-term use of HCQ or young women receiving HCQ were associated with a higher aHR for PVD in the ILD cohort. These findings indicated interplay of the primary immunologic effect of ILD, comorbidities, women, age and virus in the HCQ users.

20.
J Chin Med Assoc ; 85(3): 369-374, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35019867

RESUMO

BACKGROUND: Orthotopic liver transplantation (OLT) is an established therapeutic option for pediatric end-stage liver disease (PELD). The postoperative respiratory conditions of OLT recipients may be associated with subsequent clinical outcomes including length of stay (LOS) in the pediatric intensive care unit (PICU). This study aimed to characterize the postoperative respiratory conditions, associated factors, and outcomes after pediatric OLT. METHODS: Clinical data of children receiving OLT from July 2014 to July 2020 were retrospectively collected. Postoperative respiratory conditions were defined as time to extubation, significant pleural effusion, and initial postoperative PaO2/FiO2 ratio. Logistic and multiple regressions were applied to analyze the associations among clinical factors, postoperative respiratory conditions, and clinical outcomes. RESULTS: Twenty-two patients with median age of 1.4-year-old (range: 25 days to 12 years old) were analyzed. Mortality within 28 days was 4.5% and median LOS in the PICU was 18 days. Of 22 patients, 11 patients (50.0%) were extubated over 24 hours after surgery, and 8 patients (36.4%) required drainage for pleural effusions. Longer LOS in the PICU were noted in patients extubated over 24 hours (p = 0.008), complicated with significant pleural effusions (p = 0.02) after surgery, and having low initial postoperative PaO2/FiO2 (<300 mmHg) (p = 0.001). Among clinical factors, massive intraoperative blood transfusion (>40 mL/kg) was significantly associated with prolonged intubations, significant pleural effusions, low initial postoperative PaO2/FiO2, and prolonged LOS in the PICU (>14 days). The initial postoperative PaO2/FiO2 significantly depended on age, disease severity (PELD score), and whether the patient received massive intraoperative blood transfusion. CONCLUSION: Pediatric patients of OLT with poor postoperative respiratory conditions including low initial PaO2/FiO2 ratio, extubation over 24 hours or significant pleural effusions have longer LOS in the PICU, and the requirement of massive intraoperative transfusion was a risk factor for both poor postoperative respiratory conditions and prolonged LOS in the PICU.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Derrame Pleural , Síndrome do Desconforto Respiratório , Adulto , Criança , Doença Hepática Terminal/etiologia , Humanos , Tempo de Internação , Transplante de Fígado/efeitos adversos , Derrame Pleural/etiologia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA