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1.
World J Transplant ; 14(2): 92528, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38947972

RESUMO

BACKGROUND: Portal vein arterialization (PVA) has been used in liver transplantation (LT) to maximize oxygen delivery when arterial circulation is compromised or has been used as an alternative reperfusion technique for complex portal vein thrombosis (PVT). The effect of PVA on portal perfusion and primary graft dysfunction (PGD) has not been assessed. AIM: To examine the outcomes of patients who required PVA in correlation with their LT procedure. METHODS: All patients receiving PVA and LT at the Fundacion Santa Fe de Bogota between 2011 and 2022 were analyzed. To account for the time-sensitive effects of graft perfusion, patients were classified into two groups: prereperfusion (pre-PVA), if the arterioportal anastomosis was performed before graft revascularization, and postreperfusion (post-PVA), if PVA was performed afterward. The pre-PVA rationale contemplated poor portal hemodynamics, severe vascular steal, or PVT. Post-PVA was considered if graft hypoperfusion became evident. Conservative interventions were attempted before PVA. RESULTS: A total of 25 cases were identified: 15 before and 10 after graft reperfusion. Pre-PVA patients were more affected by diabetes, decompensated cirrhosis, impaired portal vein (PV) hemodynamics, and PVT. PGD was less common after pre-PVA (20.0% vs 60.0%) (P = 0.041). Those who developed PGD had a smaller increase in PV velocity (25.00 cm/s vs 73.42 cm/s) (P = 0.036) and flow (1.31 L/min vs 3.34 L/min) (P = 0.136) after arterialization. Nine patients required PVA closure (median time: 62 d). Pre-PVA and non-PGD cases had better survival rates than their counterparts (56.09 months vs 22.77 months and 54.15 months vs 31.91 months, respectively). CONCLUSION: This is the largest report presenting PVA in LT. Results suggest that pre-PVA provides better graft perfusion than post-PVA. Graft hyperperfusion could play a protective role against PGD.

2.
Am J Trop Med Hyg ; 109(2): 332-334, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37364861

RESUMO

Strongyloides stercoralis infection is a common infection in tropical and subtropical regions and is considered one of the "neglected tropical diseases." Owing to its life cycle, this infection can remain undetectable for years, preventing an early diagnosis and prompt treatment. We report the case of a 65-year-old woman who presented to us with a history of nausea, abdominal pain, bloating, and weight loss and, after initial radiologic and laboratory workup, was diagnosed with a periampullary mass with no secondary spread. She underwent an uneventful pylorus-preserving pancreatoduodenectomy, and on histopathological study of the lesion, a diagnosis of S. stercoralis infection was confirmed. This case stands out because of the importance of keeping S. stercoralis infections as a differential diagnosis of periampullary masses, particularly when the patient comes from regions where S. stercoralis is prevalent.


Assuntos
Duodenopatias , Strongyloides stercoralis , Estrongiloidíase , Duodenopatias/etiologia , Constrição Patológica/etiologia , Estrongiloidíase/complicações , Estrongiloidíase/diagnóstico , Humanos , Feminino , Idoso
3.
Bioeng Transl Med ; 8(2): e10444, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36925691

RESUMO

Clinical islet transplantation for treatment of type 1 diabetes (T1D) is limited by the shortage of pancreas donors and need for lifelong immunosuppressive therapy. A convection-driven intravascular bioartificial pancreas (iBAP) based on highly permeable, yet immunologically protective, silicon nanopore membranes (SNM) holds promise to sustain islet function without the need for immunosuppressants. Here, we investigate short-term functionality of encapsulated human islets in an iBAP prototype. Using the finite element method (FEM), we calculated predicted oxygen profiles within islet scaffolds at normalized perifusion rates of 14-200 nl/min/IEQ. The modeling showed the need for minimum in vitro and in vivo islet perifusion rates of 28 and 100 nl/min/IEQ, respectively to support metabolic insulin production requirements in the iBAP. In vitro glucose-stimulated insulin secretion (GSIS) profiles revealed a first-phase response time of <15 min and comparable insulin production rates to standard perifusion systems (~10 pg/min/IEQ) for perifusion rates of 100-200 nl/min/IEQ. An intravenous glucose tolerance test (IVGTT), performed at a perifusion rate of 100-170 nl/min/IEQ in a non-diabetic pig, demonstrated a clinically relevant C-peptide production rate (1.0-2.8 pg/min/IEQ) with a response time of <5 min.

4.
Nat Commun ; 14(1): 4890, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644033

RESUMO

The definitive treatment for end-stage renal disease is kidney transplantation, which remains limited by organ availability and post-transplant complications. Alternatively, an implantable bioartificial kidney could address both problems while enhancing the quality and length of patient life. An implantable bioartificial kidney requires a bioreactor containing renal cells to replicate key native cell functions, such as water and solute reabsorption, and metabolic and endocrinologic functions. Here, we report a proof-of-concept implantable bioreactor containing silicon nanopore membranes to offer a level of immunoprotection to human renal epithelial cells. After implantation into pigs without systemic anticoagulation or immunosuppression therapy for 7 days, we show that cells maintain >90% viability and functionality, with normal or elevated transporter gene expression and vitamin D activation. Despite implantation into a xenograft model, we find that cells exhibit minimal damage, and recipient cytokine levels are not suggestive of hyperacute rejection. These initial data confirm the potential feasibility of an implantable bioreactor for renal cell therapy utilizing silicon nanopore membranes.


Assuntos
Nanoporos , Silício , Humanos , Animais , Suínos , Estudos de Viabilidade , Rim , Reatores Biológicos , Terapia Baseada em Transplante de Células e Tecidos , Células Epiteliais
5.
J Biomed Mater Res A ; 109(12): 2438-2448, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34196100

RESUMO

Type 1 diabetic patients with severe hypoglycemia unawareness have benefitted from cellular therapies, such as pancreas or islet transplantation; however, donor shortage and the need for immunosuppression limits widespread clinical application. We previously developed an intravascular bioartificial pancreas (iBAP) using silicon nanopore membranes (SNM) for immunoprotection. To ensure ample nutrient delivery, the iBAP will need a cell scaffold with high hydraulic permeability to provide mechanical support and maintain islet viability and function. Here, we examine the feasibility of superporous agarose (SPA) as a potential cell scaffold in the iBAP. SPA exhibits 66-fold greater hydraulic permeability than the SNM along with a short (<10 µm) diffusion distance to the nearest islet. SPA also supports short-term functionality of both encapsulated human islets and stem-cell-derived enriched ß-clusters in a convection-based system, demonstrated by high viability (>95%) and biphasic insulin responses to dynamic glucose stimulus. These findings suggest that the SPA scaffold will not limit nutrient delivery in a convection-based bioartificial pancreas and merits continued investigation.


Assuntos
Células Secretoras de Insulina , Ilhotas Pancreáticas , Pâncreas Artificial , Sefarose/química , Transplante de Células-Tronco/métodos , Alicerces Teciduais , Adulto , Diabetes Mellitus Tipo 1/terapia , Glucose/farmacologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas , Membranas Artificiais , Nanoporos , Silício
6.
JGH Open ; 4(4): 603-610, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32782945

RESUMO

BACKGROUND AND AIM: Liver disease refers to a set of pathologies resulting from the interruption of liver function or the poor functioning of the liver. The estimation of morbidity and mortality due to liver disease and the context in which the disease develops are determining factors for public policies related to liver disease and its causes. The primary etiologies are cirrhosis and hepatocellular carcinoma, which are directly related to hepatitis B and C virus and alcohol consumption. Followed by hepatotoxic drug use, autoimmune hepatitis, cholestatic diseases, genetic abnormalities, and nonalcoholic steatohepatitis. METHODS: A descriptive cross-sectional study was conducted to estimate the prevalence of liver disease in Colombia between 2009 and 2016. Using the Data Warehouse-Cube of SISPRO as the primary source of the data, prevalence proportions were calculated and adjusted according to the Bennett Horiuchi method. The relationship with alcohol consumption and the index of unsatisfied basic needs based on estimates from 2005 were considered as sociodemographic variables. RESULTS: The prevalence of liver disease differs with regard to the type of illness, sex and age of the patient, access to medical attention, and geographical location. CONCLUSIONS: As liver disease is a public health problem, it requires early intervention such as raising awareness and prevention strategies, along with postdiagnosis care channels for treatment, rehabilitation, and palliation. By implementing these strategies, public health will be positively impacted, health care resources will be optimized, and more productive years of life are available for the citizens of the country.

7.
ACS Appl Mater Interfaces ; 12(26): 29861-29867, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32506900

RESUMO

Graphene-coated polypropylene (PP) textile fibers are presented for their use as temperature sensors. These temperature sensors show a negative thermal coefficient of resistance (TCR) in a range between 30 and 45 °C with good sensitivity and reliability and can operate at voltages as low as 1 V. The analysis of the transient response of the temperature on resistance of different types of graphene produced by chemical vapor deposition (CVD) and shear exfoliation of graphite (SEG) shows that trilayer graphene (TLG) grown on copper by CVD displays better sensitivity due to the better thickness uniformity of the film and that carbon paste provides good contact for the measurements. Along with high sensitivity, TLG on PP shows not only the best response but also better transparency, mechanical stability, and washability compared to SEG. Temperature-dependent Raman analysis reveals that the temperature has no significant effect on the peak frequency of PP and expected effect on graphene in the demonstrated temperature range. The presented results demonstrate that these flexible, lightweight temperature sensors based on TLG with a negative TCR can be easily integrated in fabrics.

8.
Clin Exp Rheumatol ; 27(3): 439-45, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19604436

RESUMO

OBJECTIVE: To determine the relationship between anthropometric measurements and disease activity, functional capacity, quality of life and radiology in Spanish patients with ankylosing spondylitis (AS). PATIENTS AND METHODS: A cross-sectional study was made of 842 patients with definite ankylosing spondylitis (REGISPONSER). Sociodemographic data, spinal mobility measurements, Bath AS disease activity index (BASDAI), nocturnal pain, Bath AS radiology index (BASRI), Bath AS functional index (BASFI), the Short-Format 12 (SF-12) and the AS specific quality of life (ASQoL) questionnaire were applied. Pearson correlation coefficient analysis and regression models were constructed. RESULTS: There was moderate correlation between fingertip-to-floor distance and lateral cervical rotation with the BASFI (p<0.01). Good correlation was evident between wall-occiput distance and lateral cervical rotation with the BASRI (p<0.01). Moderate correlation was found between chest expansion, the Schober modified test and fingertip-to-floor distance with the total BASRI (p<0.01). The anthropometric measurement with the lowest correlation value was lateral lumbar flexion. Significant association was found between the Schober modified test and BASFI, BASDAI and BASRI (R(2) = 0.37; p<0.001); chest expansion and BASFI, BASDAI and BASRI (R(2) = 0.25; p<0.001); wall-occiput distance and BASFI, BASRI and ASQoL (R(2) = 0.44; p<0.001); fingertip-to-floor distance and BASFI and BASRI (R(2) = 0.30; p<0.001); and lateral cervical rotation and BASFI and BASRI (R(2) = 0.34; p<0.001). CONCLUSION: In our study, wall-occiput distance and lateral cervical rotation showed the strongest correlation to BASRI. Similarly, fingertip-to-floor distance and lateral cervical rotation exhibited the closest correlation to BASFI.


Assuntos
Vértebras Cervicais/fisiopatologia , Qualidade de Vida , Amplitude de Movimento Articular/fisiologia , Índice de Gravidade de Doença , Espondiloartropatias/diagnóstico por imagem , Espondiloartropatias/fisiopatologia , Adulto , Artralgia/fisiopatologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Radiografia , Sistema de Registros , Análise de Regressão , Espanha , Espondiloartropatias/psicologia
9.
Adv Sci (Weinh) ; 6(15): 1802318, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31406661

RESUMO

One of the main advantages of 2D materials for various applications is that they can be prepared in form of water-based solutions. The high yield and cost-effectiveness of this method make them of great interest for printed electronics, composites, and bio- and healthcare technologies. However, once deposited on a substrate, etching away these solution-processed materials is a difficult task, yet crucial for pattern definition and thus device fabrication. In particular, the realization of micrometer-sized patterns requires mesh and paste optimization when screen-printed or solvent-engineered and surface functionalization when inkjet-printed, both usually involving additional postdeposition steps. These constraints are holding back the integration of these 2D materials in devices and applications. In this work, a method for the fabrication of micrometer-sized well-defined patterns in water-based 2D materials is presented, with an extensive characterization of the films and patterns obtained. The method is ultimately used to create humidity sensors with performance comparable to that of commercial ones. These sensor devices are fabricated onto a 4' silicon and polyethylene terephthalate (PET) wafers to create all-graphene humidity sensors that are flexible, transparent, and compatible with current complementary metal-oxide-semiconductor (CMOS) and roll-to-roll workflows.

10.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535913

RESUMO

Introduction: Liver diseases have a significant impact on global morbidity and mortality rates, primarily attributed to cirrhosis and hepatocellular carcinoma. However, the true extent of their impact on patients, healthcare systems, and countries is often underestimated. Materials and methods: This descriptive, cross-sectional study aimed to determine the economic burden associated with premature deaths caused by cirrhosis and primary liver cancer. The economic assessment was conducted by analyzing potentially productive years of life lost (PPYLL) due to liver diseases in Colombia between 2009 and 2016. Results and conclusions: The total burden of liver disease accounted for 687,861 disability-adjusted life years (DALYs). Men experienced a higher number of years of life lost from mortality (YLL), while women had a greater number of years lived with a disability (YLD). The economic burden of deaths caused by cirrhosis and primary liver cancer exceeded USD 8.6 million, highlighting the urgency to enhance intervention strategies ranging from promotion and prevention to timely diagnosis and treatment.


Introducción: la enfermedad hepática representa una de las principales causas de morbimortalidad a nivel mundial, principalmente por cirrosis y hepatocarcinoma; sin embargo, se subestima su impacto para el paciente, sistema de salud y el país. Materiales y métodos: estudio descriptivo de corte transversal que determinó la carga económica asociada a las muertes prematuras por cirrosis y tumores primarios del hígado, mediante la valoración económica de los años productivos de vida potencialmente perdidos (APVPP) en Colombia y de enfermedad hepática en Colombia entre 2009 y 2016. Resultados y conclusiones: la carga total de enfermedad hepática representó 687,861 años de vida saludable perdidos ajustados por discapacidad (AVAD), los hombres con mayores años de vida perdidos por muerte prematura (APMP) y las mujeres con mayores años vividos con discapacidad (AVD). Las muertes por cirrosis y tumores primarios del hígado representan una carga económica que supera los 8,6 millones de dólares, lo cual refleja la necesidad de fortalecer las estrategias de intervención desde la promoción y prevención hasta el diagnóstico y tratamiento oportuno.

11.
Adv Mater ; 29(23)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28418620

RESUMO

The combination of graphene with semiconductor materials in heterostructure photodetectors enables amplified detection of femtowatt light signals using micrometer-scale electronic devices. Presently, long-lived charge traps limit the speed of such detectors, and impractical strategies, e.g., the use of large gate-voltage pulses, have been employed to achieve bandwidths suitable for applications such as video-frame-rate imaging. Here, atomically thin graphene-WS2 heterostructure photodetectors encapsulated in an ionic polymer are reported, which are uniquely able to operate at bandwidths up to 1.5 kHz whilst maintaining internal gain as large as 106 . Highly mobile ions and the nanometer-scale Debye length of the ionic polymer are used to screen charge traps and tune the Fermi level of the graphene over an unprecedented range at the interface with WS2 . Responsivity R = 106 A W-1 and detectivity D* = 3.8 × 1011 Jones are observed, approaching that of single-photon counters. The combination of both high responsivity and fast response times makes these photodetectors suitable for video-frame-rate imaging applications.

12.
ACS Appl Mater Interfaces ; 8(26): 16541-5, 2016 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-27299371

RESUMO

Alternating current electroluminescent technology allows the fabrication of large area, flat and flexible lights. Presently the maximum size of a continuous panel is limited by the high resistivity of available transparent electrode materials causing a visible gradient of brightness. Here, we demonstrate that the use of the best known transparent conductor FeCl3-intercalated few-layer graphene boosts the brightness of electroluminescent devices by 49% compared to pristine graphene. Intensity gradients observed for high aspect ratio devices are undetectable when using these highly conductive electrodes. Flat lights on polymer substrates are found to be resilient to repeated and flexural strains.

14.
Rev. ADM ; 68(2): 89-92, mar.-abr. 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-655849

RESUMO

La cirugía periapical se desarrolló como una alternativa ante los fracasos en los tratamientos endodónticos convencionales En este trabajo se presenta un caso de cirugía endodóntica, donde fue utilizado un microscopio clínico durante el procedimiento quirúrgico, la magnificación de las imágenes transoperatorias permitió resolver favorablemente las complicaciones y con ello mejorar el pronóstico final del tratamiento.


Assuntos
Humanos , Masculino , Adulto , Doenças Periodontais/cirurgia , Microcirurgia/métodos , Microscopia/métodos , Prognóstico , Radiografia Dentária Digital
15.
Educ. fis. deporte ; 29(1): 95-101, ene.-jun. 2010.
Artigo em Espanhol | LILACS | ID: lil-599045

RESUMO

El objetivo de esta investigación consiste en estructurar la historia de vida de una mujer deportista paralímpica colombiana, reconociendo al deporte como un medio de transformación de la vida de los sujetos. Se realizaron entrevistas semiestructuradas realizadas a la deportista paralímpica colombiana Naiver Ome, a su entrenador, a su novio, a su hermana y a una amiga. Las preguntas base se clasificaron según ocho categorías: familiar, social, deportiva, educativa, médica, religiosa, legal y económica. Por medio de esta historia de vida se reconoce al deporte como un importante medio para la transformación de una persona en condición de discapacidad.


This research aims to structure the biography of a Colombian paralympic sport woman, in order to recognize sport as a means of transformation in the individuals’ life. Semistructured interviews were made to Colombian paralympic sportwoman Naiver Ome, her coach, her fiancé, her sister and a friend of her. Key questions were classified under eight categories: social, sporty, educational, medical, religious, legal and economic. Through this history sport is identified as an important means to transform a disabled person.


Assuntos
Humanos , Feminino , Pessoas com Deficiência , Educação , Educação Física e Treinamento
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