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1.
Support Care Cancer ; 32(5): 273, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587665

RESUMEN

PURPOSE: Health service use is most intensive in the final year of a person's life, with 80% of this expenditure occurring in hospital. Close involvement of primary care services has been promoted to enhance quality end-of-life care that is appropriate to the needs of patients. However, the relationship between primary care involvement and patients' use of hospital care is not well described. This study aims to examine primary care use in the last year of life for cancer patients and its relationship to hospital usage. METHODS: Retrospective cohort study in Victoria, Australia, using linked routine care data from primary care, hospital and death certificates. Patients were included who died related to cancer between 2008 and 2017. RESULTS: A total of 758 patients were included, of whom 88% (n = 667) visited primary care during the last 6 months (median 9.1 consultations). In the last month of life, 45% of patients were prescribed opioids, and 3% had imaging requested. Patients who received home visits (13%) or anticipatory medications (15%) had less than half the median bed days in the last 3 months (4 vs 9 days, p < 0.001, 5 vs 10 days, p = 0.001) and 1 month of life (0 vs 2 days, p = 0.002, 0 vs 3 days, p < 0.001), and reduced emergency department presentations (32% vs 46%, p = 0.006, 31% vs 47% p < 0.001) in the final month. CONCLUSION: This study identifies two important primary care processes-home visits and anticipatory medication-associated with reduced hospital usage and intervention at the end of life.


Asunto(s)
Muerte , Neoplasias , Humanos , Estudios Retrospectivos , Hospitales , Neoplasias/terapia , Victoria , Atención Primaria de Salud
2.
Georgian Med News ; (346): 21-26, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38501616

RESUMEN

Immunization is an effective and safest way to prevent vaccine-preventable diseases and thereby reduce morbidity and mortality in children. Injections given for immunization are the most usual ground in order to abstract agony or pain, which is the fifth vital sign leading to long-term physically and psychologically detrimental effects. A basic experimental (control group only for post-test) design using the technique of probability of simple random sampling in order to obtain sample size 105 was conducted in an Immunization Clinic at a selected PHC, Tamil Nadu, India. Ice cube was applied for about 30 seconds that is enfolded with gauze and then injected intramuscularly to administer the IM vaccine. In order to assess the pain level, an observation checklist based on Children's Hospital Eastern Ontario pain scale and Wong Baker's Faces pain scale was used. The study results manifest the higher statistical difference in the level of children's pain between the control groups and the experimental groups at a significance level of p<0.001. In order to reduce the pain level, the application of ice at LI-4 acupoint is effective. The children who are being vaccinated pass through stressful events through the application of an intramuscular injection. The findings revealed that ice application at LI-4 acupoint was very effective in pain reduction, which is a simple, safe, non-invasive, very efficient, easy-to-administer intervention and cost-effective without side effects than any other pharmacological pain intervention.


Asunto(s)
Puntos de Acupuntura , Dolor , Niño , Humanos , Inyecciones Intramusculares/efectos adversos , India , Dolor/prevención & control , Vacunación
3.
Diabet Med ; 37(2): 362-368, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31559651

RESUMEN

AIM: To compare the characteristics of and outcomes for people with malignancies with and without a co-diagnosis of diabetes. METHODS: Emergency department and hospital discharge data from a single centre for the period between 1 January 2015 and 31 December 2017 were used to identify people with a diagnosis of a malignancy and diabetes. Multivariate Cox regression models were used to estimate the effect of diabetes on all-cause mortality. A truncated negative binomial regression model was used to assess the impact of diabetes on length of hospital inpatient stay. Prentice-Williams-Peterson total time models were used to assess the effect of diabetes on number of emergency department re-presentations and inpatient re-admissions. RESULTS: Of 7004 people identified with malignancies, 1195 (17.1%) were also diagnosed with diabetes. A diagnosis of diabetes was associated with a greater number of inpatient re-admissions [adjusted hazard ratio 1.13 (95% CI 1.03, 1.24)], a greater number of emergency department re-presentations [adjusted hazard ratio 1.13 (95% CI 1.05, 1.22)] and longer length of stay [adjusted incidence rate ratio 1.14 (95% CI 1.04, 1.25)]. A co-diagnosis of diabetes was also associated with a 48% increased risk of all-cause mortality [adjusted hazard ratio 1.48 (95% CI 1.22-1.76)]. CONCLUSIONS: People with malignancies and diabetes had significantly more emergency department presentations, more inpatient admissions, longer length of hospital stay and higher rates of all-cause mortality compared to people with a malignancy without diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Mortalidad , Neoplasias/epidemiología , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Estudios de Casos y Controles , Causas de Muerte , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos
5.
J Appl Toxicol ; 39(3): 461-472, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30307041

RESUMEN

Recent advances in developing in vitro tissue models show that function of hepatocytes is altered in when cultured in 3D configuration and co-culturing with various non-parenchymal cells. However, tissue source for such non-parenchymal cells on viability and metabolic products of hepatocytes have not been explored. In this study, we evaluated the effect of 2D and 3D cultures either with HepaRG cells alone or in combination with liver sinusoidal endothelial cells (LSECs) and human umbilical vein ECs (HUVECs). For 3D cultures, we used chitosan-gelatin porous structures formed by freeze-drying. We cultured cells for 8 days before challenging with 1 mm acetaminophen (APAP) and assessed APAP, APAP-sulfate and APAP-glucuronide for 24 hours at 6-hour time intervals using high-performance liquid chromatography. We used multiple methods (phase contrast, confocal and scanning electron microscopy and histology via hematoxylin and eosin staining) to ensure cell distribution. We also measured total protein content and albumin secretion and viability. HUVEC 3D co-cultures showed the lowest HepaRG cell viability, while both 2D and 3D LSEC co-cultures had highest HepaRG cell viability. In addition, 3D cultures had significantly higher EC viability relative to 2D cultures. Further, HUVEC co-cultures showed reduced total protein content and albumin expression as early as day 4. However, urea production on a total protein content basis did not change. In addition, LSEC 3D co-cultures had the highest APAP conversion with reduced APAP-sulfate and APAP-glucuronide formation. CYP3A4 was higher in co-culture with HUVEC for 2D and 3D cultures. In conclusion, HepaRG cells with EC co-cultures demonstrated sensitivity to the EC line used.


Asunto(s)
Acetaminofén/metabolismo , Células Endoteliales/fisiología , Hepatocitos/metabolismo , Supervivencia Celular , Células Cultivadas , Técnicas de Cocultivo , Citocromo P-450 CYP3A/metabolismo , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Proteínas/análisis
6.
Biotechnol Bioeng ; 112(2): 393-404, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25116006

RESUMEN

In this study, the distribution of oxygen and glucose was evaluated along with consumption by hepatocytes using three different approaches. The methods include (i) Computational Fluid Dynamics (CFD) simulation, (ii) residence time distribution (RTD) analysis using a step-input coupled with segregation model or dispersion model, and (iii) experimentally determined consumption by HepG2 cells in an open-loop. Chitosan-gelatin (CG) scaffolds prepared by freeze-drying and polycaprolactone (PCL) scaffolds prepared by salt leaching technique were utilized for RTD analyses. The scaffold characteristics were used in CFD simulations i.e. Brinkman's equation for flow through porous medium, structural mechanics for fluid induced scaffold deformation, and advection-diffusion equation coupled with Michaelis-Menten rate equations for nutrient consumption. With the assumption that each hepatocyte behaves like a micro-batch reactor within the scaffold, segregation model was combined with RTD to determine exit concentration. A flow rate of 1 mL/min was used in the bioreactor seeded with 0.6 × 10(6) HepG2 cells/cm(3) on CG scaffolds and oxygen consumption was measured using two flow-through electrodes located at the inlet and outlet. Glucose in the spent growth medium was also analyzed. RTD results showed distribution of nutrients to depend on the surface characteristics of scaffolds. Comparisons of outlet oxygen concentrations between the simulation results, and experimental results showed good agreement with the dispersion model. Outlet oxygen concentrations from segregation model predictions were lower. Doubling the cell density showed a need for increasing the flow rate in CFD simulations. This integrated approach provide a useful strategy in designing bioreactors and monitoring tissue regeneration.


Asunto(s)
Reactores Biológicos , Glucosa/metabolismo , Oxígeno/metabolismo , Andamios del Tejido/química , Proliferación Celular , Quitosano/química , Gelatina/química , Células Hep G2 , Humanos , Poliésteres/química , Porosidad , Factores de Tiempo
7.
Int J Qual Health Care ; 27(4): 328-33, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26045514

RESUMEN

PURPOSE: To develop a consensus opinion regarding capturing diagnosis-timing in coded hospital data. METHODS: As part of the World Health Organization International Classification of Diseases-11th Revision initiative, the Quality and Safety Topic Advisory Group is charged with enhancing the capture of quality and patient safety information in morbidity data sets. One such feature is a diagnosis-timing flag. The Group has undertaken a narrative literature review, scanned national experiences focusing on countries currently using timing flags, and held a series of meetings to derive formal recommendations regarding diagnosis-timing reporting. RESULTS: The completeness of diagnosis-timing reporting continues to improve with experience and use; studies indicate that it enhances risk-adjustment and may have a substantial impact on hospital performance estimates, especially for conditions/procedures that involve acutely ill patients. However, studies suggest that its reliability varies, is better for surgical than medical patients (kappa in hip fracture patients of 0.7-1.0 versus kappa in pneumonia of 0.2-0.6) and is dependent on coder training and setting. It may allow simpler and more precise specification of quality indicators. CONCLUSIONS: As the evidence indicates that a diagnosis-timing flag improves the ability of routinely collected, coded hospital data to support outcomes research and the development of quality and safety indicators, the Group recommends that a classification of 'arising after admission' (yes/no), with permitted designations of 'unknown or clinically undetermined', will facilitate coding while providing flexibility when there is uncertainty. Clear coding standards and guidelines with ongoing coder education will be necessary to ensure reliability of the diagnosis-timing flag.


Asunto(s)
Diagnóstico , Hospitales/estadística & datos numéricos , Clasificación Internacional de Enfermedades/normas , Seguridad del Paciente/normas , Calidad de la Atención de Salud/normas , Comités Consultivos , Recolección de Datos/métodos , Recolección de Datos/normas , Recolección de Datos/estadística & datos numéricos , Mortalidad Hospitalaria , Hospitales/normas , Humanos , Seguridad del Paciente/estadística & datos numéricos , Mejoramiento de la Calidad/normas , Mejoramiento de la Calidad/estadística & datos numéricos , Calidad de la Atención de Salud/estadística & datos numéricos , Factores de Tiempo
8.
Int J Qual Health Care ; 26(5): 511-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24990594

RESUMEN

Hospital-based medical records are abstracted to create International Classification of Disease (ICD) coded discharge health data in many countries. The 'main condition' is not defined in a consistent manner internationally. Some countries employ a 'reason for admission' rule as the basis for the main condition, while other countries employ a 'resource use' rule. A few countries have recently transitioned from one of these approaches to the other. The definition of 'main condition' in such ICD data matters when it is used to define a disease cohort to assign diagnosis-related groups and to perform risk adjustment. We propose a method of harmonizing the international definition to enable researchers and international organizations using ICD-coded health data to aggregate or compare hospital care and outcomes across countries in a consistent manner. Inter-observer reliability of alternative harmonization approaches should be evaluated before finalizing the definition and adopting it worldwide.


Asunto(s)
Codificación Clínica/normas , Administración Hospitalaria/normas , Clasificación Internacional de Enfermedades/normas , Internacionalidad , Humanos , Reproducibilidad de los Resultados
9.
Biotechnol Bioeng ; 109(5): 1314-25, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22125268

RESUMEN

Influence of mechanical characteristics and matrix architecture of substrates used in cell culture is an important issue to tissue engineering. Chitosan-based materials have been processed into porous structures, injectable gels and membranes, and are investigated to regenerate various tissues. However, the effect of these structures on cell growth and matrix production in accordance with each of the differing scaffolds has not been examined. We investigated the influence of porous structures, hydrogels, and membranes on the growth of normal human fibroblasts and their matrix production in a serum-free system. We used chitosan alone and in combination with gelatin. Injectable hydrogels were prepared using 2-glycerol phosphate. From the same solution, porous scaffolds and membranes were formed using controlled rate freezing and lyophilization, and air-drying, respectively. Fibroblast growth was evaluated on the 4th and 10th days using flow cytometry and CFDA-SE pre-staining. Cell morphology was assessed using actin and nucleus staining. Total protein content, collagen, tropoelastin, and MMP2/MMP-9 activity in the media supernatant were assessed by BCA, Sircol™, Fastin Elastin, and fluorogeneic peptide assays. Collagen accumulated in the matrix was assessed by Sircol™ assay after pepsin/acetic acid digestion and by Masson's Trichrome staining. These results showed increased viability of fibroblasts on chitosan-gelatin porous scaffold with decreased proliferation relative to tissue culture plastic (TCP) surface despite the cells showing spindle shape. The total protein, collagen, and tropoelastin contents were higher in the spent media from chitosan-gelatin porous scaffolds compared to other conditions. MMP2/MMP9 activity was comparable to TCP. An increase in collagen content was also observed in the matrix, suggesting increased matrix deposition. In summary, matrix production is influenced by the form of chitosan structures, which significantly affects the regenerative process.


Asunto(s)
Proliferación Celular , Quitosano , Matriz Extracelular/metabolismo , Fibroblastos/fisiología , Gelatina , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Fibroblastos/metabolismo , Citometría de Flujo , Humanos , Coloración y Etiquetado
10.
Intern Med J ; 42(9): 1053-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24020345

RESUMEN

Patients with chronic obstructive pulmonary disease experience a substantial symptom burden, high levels of psychosocial need and significant mortality. This epidemiological study reveals that the majority of patients are cared for in the public hospital system (64%) and generally die in hospital (72%) with a number of identifiable predictors of 6-month mortality. Our results suggest that palliative care services need to be redirected from a community-based admission focus to a model that is responsive to emergency and acute care hospital systems.


Asunto(s)
Cuidados Paliativos/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/terapia , Anciano , Anciano de 80 o más Años , Asma/mortalidad , Asma/terapia , Comorbilidad , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Necesidades y Demandas de Servicios de Salud , Hospitales Privados/estadística & datos numéricos , Hospitales Públicos/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Admisión del Paciente/estadística & datos numéricos , Readmisión del Paciente/estadística & datos numéricos , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Respiración Artificial/estadística & datos numéricos , Estudios Retrospectivos , Victoria/epidemiología
11.
Intern Med J ; 42(7): 816-22, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22152049

RESUMEN

BACKGROUND: The information needs of patients with chronic obstructive pulmonary disease (COPD) towards the end of life are poorly understood. AIM: This study explored the views of patients with COPD and healthcare professionals, focusing upon information needs and treatment preferences. METHOD: In-depth, semi-structured interviews were held with patients with COPD following admission to hospital with respiratory failure, and focus groups held with healthcare professionals from hospital and community settings. RESULTS: Ten patients were interviewed, who had a median 4 previous hospital admissions, and had smoked for median 47 years. Five focus groups were held with 31 healthcare professionals (18 nurses, 7 doctors, 6 allied health). The theme underpinning all discussions was of tension between maintaining hope and negotiating the reality of the illness and its consequences. Within this theme, patients tended to be optimistic, viewed acute exacerbations as separate from their underlying chronic illness, and were keen for intensive treatments, including intubation if acutely unwell. They had little understanding of the complexities of decision-making around treatment escalation. Both patients and health workers believed that information around end of life should be offered routinely, but delivered in a manner that recognises and maintains a form of hope. CONCLUSION: Patients and healthcare professionals believe information around illness course, future goals and treatment is important to care. An expanded view of hope may assist when providing such information, including when discussing goals of care in the setting of advanced illness.


Asunto(s)
Personal de Salud/psicología , Negociación/psicología , Educación del Paciente como Asunto , Relaciones Profesional-Familia , Enfermedad Pulmonar Obstructiva Crónica/psicología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Negociación/métodos , Educación del Paciente como Asunto/métodos
12.
Rev Epidemiol Sante Publique ; 59(5): 341-50, 2011 Oct.
Artículo en Francés | MEDLINE | ID: mdl-21899967

RESUMEN

BACKGROUND: In the United States, the Agency for Healthcare Research and Quality (AHRQ) has developed 20 Patient Safety Indicators (PSIs) to measure the occurrence of hospital adverse events from medico-administrative data coded according to the ninth revision of the international classification of disease (ICD-9-CM). The adaptation of these PSIs to the WHO version of ICD-10 was carried out by an international consortium. METHODS: Two independent teams transcoded ICD-9-CM diagnosis codes proposed by the AHRQ into ICD-10-WHO. Using a Delphi process, experts from six countries evaluated each code independently, stating whether it was "included", "excluded" or "uncertain". During a two-day meeting, the experts then discussed the codes that had not obtained a consensus, and the additional codes proposed. RESULTS: Fifteen PSIs were adapted. Among the 2569 proposed diagnosis codes, 1775 were unanimously adopted straightaway. The 794 remaining codes and 2541 additional codes were discussed. Three documents were prepared: (1) a list of ICD-10-WHO codes for the 15 adapted PSIs; (2) recommendations to the AHRQ for the improvement of the nosological frame and the coding of PSI with ICD-9-CM; (3) recommendations to the WHO to improve ICD-10. CONCLUSIONS: This work allows international comparisons of PSIs among the countries using ICD-10. Nevertheless, these PSIs must still be evaluated further before being broadly used.


Asunto(s)
Codificación Clínica/métodos , Clasificación Internacional de Enfermedades , Seguridad del Paciente , Indicadores de Calidad de la Atención de Salud , United States Agency for Healthcare Research and Quality , Algoritmos , Codificación Clínica/organización & administración , Codificación Clínica/normas , Grupos Diagnósticos Relacionados/clasificación , Francia , Agencias de los Sistemas de Salud/organización & administración , Agencias de los Sistemas de Salud/normas , Humanos , Clasificación Internacional de Enfermedades/normas , Cooperación Internacional , Indicadores de Calidad de la Atención de Salud/clasificación , Indicadores de Calidad de la Atención de Salud/organización & administración , Indicadores de Calidad de la Atención de Salud/normas , Terminología como Asunto , Estados Unidos
13.
Expert Opin Drug Deliv ; 17(2): 213-223, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31937127

RESUMEN

Introduction: Combination therapy has been explored for its potential to reduce or eliminate multidrug resistance in treating different types of cancer including leukemia. Nutraceutical, small molecular drugs, and small interfering ribonucleic acid (siRNA) are some of the effective drugs. In order to avoid off-site targeting, reduce the dosage required, and increase the half-life of the drug in the circulation system, drug delivery vehicles, such as nanoparticles and microfibers have been explored.Areas covered: This review summarizes various therapies utilized in treating leukemia based on their effectiveness in inducing protein inhibition and/or apoptosis. In particular, treatment effectiveness using combination therapy using various devices is addressed. Recently explored drug delivery methods are reviewed, providing examples and their applications in cancer treatment. The drug listing, delivery systems classifications, along with the general modeling approach in this review, provide, to a full extent, a basis for cancer drug delivery future studies.Expert opinion: The reviewer's opinion tackles the potential of using a multi-delivery system to deliver multiple drugs, providing better control upon drug release and targeting. Both local and systemic delivery are considered and explored for their potential targets. Researchers are advised to pre-consider all aspects associated with their desired delivery method.


Asunto(s)
Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Antineoplásicos/química , Combinación de Medicamentos , Liberación de Fármacos , Humanos , Modelos Biológicos
14.
Comput Biol Med ; 117: 103622, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32072965

RESUMEN

Using electrospun fibers to deliver therapeutic agents has gained significant attention in various applications including cancer treatment and tissue regeneration. However, the effect of fluid flow and uptake by cells on the concentration profile is not well understood. In this study, we evaluated the release of lipophilic resveratrol from poly(ε-caprolactone) (PCL)-gelatin (GT) electrospun fibers experimentally and by using computational fluid dynamics (CFD). Resveratrol containing PCL-GT electrospun fibers were formed and used in a custom-built tubular bioreactor, to assess flow effect on concentration profile over 5 days. CFD model was developed to simulate release in both static cultures and under fluid flow conditions. Resveratrol stability in the culture medium and uptake by human umbilical vein endothelial cells and K562 cells over 3 days were used in the model. The concentration profile as a function of time was simulated and validated by experiments. The effects of inlet velocity, cellular uptake rate, bioreactor's length, and surrounding tissue porosity were assessed. The release profile was mainly affected by cellular uptake and the presence of porous media. The model suggests that the perfusion velocity might not have a significant effect relative to the cellular uptake rate and porosity of the surrounding tissue.


Asunto(s)
Células Endoteliales , Poliésteres , Gelatina , Humanos , Porosidad , Resveratrol , Ingeniería de Tejidos
15.
BMC Cancer ; 9: 219, 2009 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-19580656

RESUMEN

BACKGROUND: Esophageal cancer ranks eighth in order of cancer occurrence. Its lethality primarily stems from inability to detect the disease during the early organ-confined stage and the lack of effective therapies for advanced-stage disease. Moreover, the understanding of molecular processes involved in esophageal cancer is not complete, hampering the development of efficient diagnostics and therapy. Efforts made by the scientific community to improve the survival rate of esophageal cancer have resulted in a wealth of scattered information that is difficult to find and not easily amendable to data-mining. To reduce this gap and to complement available cancer related bioinformatic resources, we have developed a comprehensive database (Dragon Database of Genes Implicated in Esophageal Cancer) with esophageal cancer related information, as an integrated knowledge database aimed at representing a gateway to esophageal cancer related data. DESCRIPTION: Manually curated 529 genes differentially expressed in EC are contained in the database. We extracted and analyzed the promoter regions of these genes and complemented gene-related information with transcription factors that potentially control them. We further, precompiled text-mined and data-mined reports about each of these genes to allow for easy exploration of information about associations of EC-implicated genes with other human genes and proteins, metabolites and enzymes, toxins, chemicals with pharmacological effects, disease concepts and human anatomy. The resulting database, DDEC, has a useful feature to display potential associations that are rarely reported and thus difficult to identify. Moreover, DDEC enables inspection of potentially new 'association hypotheses' generated based on the precompiled reports. CONCLUSION: We hope that this resource will serve as a useful complement to the existing public resources and as a good starting point for researchers and physicians interested in EC genetics. DDEC is freely accessible to academic and non-profit users at http://apps.sanbi.ac.za/ddec/. DDEC will be updated twice a year.


Asunto(s)
Bases de Datos Genéticas , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Sistemas de Administración de Bases de Datos , Bases de Datos de Proteínas , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Almacenamiento y Recuperación de la Información , Masculino , Modelos Genéticos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Programas Informáticos , Resultado del Tratamiento , Interfaz Usuario-Computador
16.
Biotechnol Bioeng ; 102(3): 935-47, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18949759

RESUMEN

Bioreactors are widely used in tissue engineering as a way to distribute nutrients within porous materials and provide physical stimulus required by many tissues. However, the fluid dynamics within the large porous structure are not well understood. In this study, we explored the effect of reactor geometry by using rectangular and circular reactors with three different inlet and outlet patterns. Geometries were simulated with and without the porous structure using the computational fluid dynamics software Comsol Multiphysics 3.4 and/or ANSYS CFX 11 respectively. Residence time distribution analysis using a step change of a tracer within the reactor revealed non-ideal fluid distribution characteristics within the reactors. The Brinkman equation was used to model the permeability characteristics with in the chitosan porous structure. Pore size was varied from 10 to 200 microm and the number of pores per unit area was varied from 15 to 1,500 pores/mm(2). Effect of cellular growth and tissue remodeling on flow distribution was also assessed by changing the pore size (85-10 microm) while keeping the number of pores per unit area constant. These results showed significant increase in pressure with reduction in pore size, which could limit the fluid flow and nutrient transport. However, measured pressure drop was marginally higher than the simulation results. Maximum shear stress was similar in both reactors and ranged approximately 0.2-0.3 dynes/cm(2). The simulations were validated experimentally using both a rectangular and circular bioreactor, constructed in-house. Porous structures for the experiments were formed using 0.5% chitosan solution freeze-dried at -80 degrees C, and the pressure drop across the reactor was monitored.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula/métodos , Ingeniería de Tejidos/métodos , Andamios del Tejido , Algoritmos , Fenómenos Biofísicos , Quitosano , Simulación por Computador , Permeabilidad , Porosidad , Programas Informáticos
17.
Biotechnol Bioeng ; 103(5): 1003-15, 2009 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19422037

RESUMEN

Flow-through bioreactors are utilized in tissue regeneration to ensure complete nutrient distribution and apply defined hydrodynamic stresses. The fundamental concepts in designing these bioreactors for regenerating large high aspect ratio tissues (large surface area relative to the thickness of the matrix such as skin, bladder, and cartilage) are not well defined. Further, tissue regeneration is a dynamic process where the porous characteristics change due to proliferation of cells, de novo deposition of matrix components, and degradation of the porous architecture. These changes affect the transport characteristics and there is an imminent need to understand the influence of these factors. Using computational fluid dynamic tools, changes in the pressure drop, shear stress distribution and nutrient consumption patterns during tissue regeneration were assessed in rectangular and circular reactors described by Lawrence et al. [Biotechnol Bioeng 2009;102(3):935-947]. Further, six new designs with different inlet and outlet shapes were analyzed. The fluid flow was defined by the Brinkman equation on the porous regions using the pore characteristics of 85 microm and 120 pores/mm(2). The minimum flow requirements to satisfy nutrient (oxygen and glucose) requirements for three different cell types (SMCs, chondrocytes, and hepatocytes) was evaluated using convective diffusion equation. For consumption reaction, the Michaelis-Menten rate law was used, with constants (k(m) and v(m) values) extracted from literature. Simulations were performed by varying the flow rate as well as the cell number. One of the circular reactors with semicircular inlet and outlet shape decreased (i) non-uniformity in hydrodynamic stress within the porous structure and (ii) non-uniform nutrient distribution. All cell types showed increased consumption of oxygen than glucose. Hepatocytes needed a very high flow rate relative to other cell types. Increase in cell number suggested a need for increasing the flow in circular reactors.


Asunto(s)
Reactores Biológicos , Medios de Cultivo/química , Alimentos , Ingeniería de Tejidos/métodos , Consumo de Oxígeno , Estrés Mecánico
18.
Int J Pharm ; 569: 118599, 2019 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-31394186

RESUMEN

In this study, we evaluated a novel combination of drug delivery devices composed of holo-transferrin conjugated liposomes for siRNA (36 nM) delivery, and electrospun polycaprolactone (PCL)-gelatin (GT) microfibers for resveratrol (40 µM) release. Single- and co-cultures of cancerous K562 cells and human umbilical vein endothelial cells (HUVECs) were used to test the efficacy and targeting over eight days. BCR-ABL siRNA-encapsulated (36 nM) holo-transferrin-conjugated PEG-liposomes were characterized using dynamic light scattering, and transmission electron microscopy. RT-qPCR was performed to assess the silencing BCR-ABL gene. Two treatment protocols were explored: i) simultaneous administration ii) delayed liposomes addition by three days based on resveratrol release profile. Formed liposomes were 123 (±6.65) nm in diameter, holo-transferrin conjugation efficiency was 85.9 (±7.30)%, and siRNA loading efficiency was 92.3 (±2.57)%. Sphingosine-1-phosphate (S1P) content was analyzed by ELISA. Targeted siRNA release in combination with resveratrol release was more potent and has long-term effects compared to bolus doses. Delayed addition of liposomes increased non-viability of K562 cells to 92.7 (±2.00)% and 94.32 (±1.70)%, in the absence and presence of HUVECs, respectively. HUVECs non-viability level was significantly lower. Using two different delivery devices approach has a broader impact on cancer treatment.


Asunto(s)
Sistemas de Liberación de Medicamentos , Proteínas de Fusión bcr-abl/genética , Neoplasias/terapia , ARN Interferente Pequeño/administración & dosificación , Resveratrol/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Gelatina/administración & dosificación , Silenciador del Gen , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Células K562 , Liposomas , Neoplasias/genética , Poliésteres/administración & dosificación
19.
ACS Appl Bio Mater ; 2(11): 4911-4921, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-35021491

RESUMEN

Micropillar patterns were fabricated and used to study cell adhesion, morphology, and function. Micropillars were produced in poly(2-hydroxyethyl methacrylate (HEMA)/N,N-(dimethylaminoethyl)methacrylate (DMAEMA)/tetraethylene glycol dimethacrylate (TEGDMA)) hydrogels using soft lithography, had dimensions of 1 µm diameter, and were either 2.05 or 4.91 µm tall. The patterned hydrogel substrates increased adhesion and induced the formation of cellular aggregates. Digital micrographs were used to quantify aggregate size and number. Differentiation of hMSCs toward adipocytes and chondrocytes was performed using the respective complete culture and differentiation medium for 2 weeks. Cells were stained for Oil red O, Alcian blue, and Type II collagen. Hydrogel substrates supported the differentiation of hMSCs to adipocytes and chondrocytes. The taller micropillar patterns supported the attachment and growth of larger aggregates and were more amenable to aid chondrogenic differentiation.

20.
Int J Popul Data Sci ; 4(1): 1097, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34095531

RESUMEN

INTRODUCTION: The growing burden of chronic diseases means some governments have been providing financial incentives for multidisciplinary care and self-management support delivered within primary care. Currently, population-based evaluations of the effectiveness of these policies are lacking. AIM: To outline the methodological approach for our study that is designed to evaluate the effectiveness (including cost) of primary care policies for chronic diseases in Australia using stroke as a case study. METHODS: Person-level linkages will be undertaken between registrants from the Australian Stroke Clinical Registry (AuSCR) and (i) Government-held Medicare Australia claims data, to identify receipt or not of chronic disease management and care coordination primary care items; (ii) state government-held hospital data, to define outcomes; and (iii) government-held pharmaceutical and aged care claims data, to define covariates. N=1500 randomly selected AuSCR registrants will be sent surveys to obtain patient experience information. In Australia, unique identifiers are unavailable. Therefore, personal-identifiers will be submitted to government data linkage units. Researchers will merge the de-identified datasets for analysis using a project identifier. An economic evaluation will also be undertaken. ANALYSIS: The index event will be the first stroke recorded in the AuSCR. Multivariable competing risks Poisson regression for multiple events, adjusted by a propensity score, will be used to test for differences in the rates of hospital presentations and medication adherence for different care (policy) types. Our estimated sample size of 25,000 patients will provide 80% estimated power (ɑ>0.05) to detect a 6-8% difference in rates. The incremental costs per Quality-adjusted life years gained of community-based care following the acute event will be estimated from a health sector perspective. CONCLUSION: Completion of this study will provide a novel and comprehensive evaluation of the effectiveness and cost-effectiveness of Australian primary care policies. Its success will enable us to highlight the value of data-linkage for this type of research.

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