Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Child Abuse Negl ; 130(Pt 3): 105298, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34462145

RESUMO

BACKGROUND: Udayan Care, an NGO based in New Delhi, India, provides alternative care to 'Children without Parental Care', in small-group residential homes. The homes have a Living In Family Environment (L.I.F.E) Model, where 'Group Care' ensures that children are loved and cared for by a group of long-term volunteers, called mentor parents, along with other care staff. A novel parenting concept, the mentor parents are ordinary individuals with extraordinary sensitivity, voluntarily committing themselves for life. They instill in children a sense of trust and belonging to the community and are concurrently empowered and fulfilled by the endeavor. OBJECTIVE: This study attempted to explore the scope and impact of a distinct mentor model in alternative child care, its positive outcomes, and some challenges faced, from the perspective of mentor parents. PARTICIPANTS AND SETTING: With a qualitative research design, interviews were conducted with the mentor parents (n = 21) from Udayan Care, to capture their experiences and perspectives. METHODS: The interviews were conducted using an indigenously developed semi-structured interview guide, and the responses were transcribed, organized, coded, and analyzed using applied thematic analysis. RESULTS: The unique roles and responsibilities that mentor parents bring to the care system were identified, along with how they add value to the mentor-mentee relationship. Some challenges in the care practice were also discerned. CONCLUSIONS: This paper gleans mentor perspectives that could be valuable for the design and implementation of mentorship programs, encouraging similar scalable models that could support the growth, development, and outcomes of children in care.


Assuntos
Tutoria , Criança , Cuidado da Criança , Humanos , Mentores , Poder Familiar , Pesquisa Qualitativa
2.
Data Brief ; 35: 106953, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33855134

RESUMO

This data article describes biomechanical and histological information of abdominal aortas harvested in autopsy. Eight abdominal aorta aneurysms (AAA) and 30 normal diameter abdominal aortas were collected and submitted to an inflation test up to their rupture. This inflation procedure was part of the research entitled "Experimental study of rupture pressure and elasticity of abdominal aortic aneurysms found at autopsy", submitted to Annals of Vascular Surgery. The rupture borders and control samples (harvested from places other than the rupture site) were submitted to uniaxial destructive tensile test and to histological analysis. The following variables were evaluated in the biomechanical test: failure stress, failure tension and failure strain. The histological processing of the samples enabled a quantitative analysis of the percentage of coverage of collagen fibers and elastic fibers in the samples. The present data could be reutilized because they are experimental evidence that cadaveric abdominal aortas, even when previously stressed by inflation, conserve significant resistance against tearing comparable to no previously stressed aortas described in the literature. Considering real whole cadaveric AAAs are especially scarce, this information would be a useful reference source for further in-depth research in the aortic biomechanics field.

3.
Ann Vasc Surg ; 70: 517-527, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32891747

RESUMO

BACKGROUND: Resistance and elasticity of normal and aneurysmal aorta walls are directly associated with this vessel's growth and rupture. This study aims to experimentally analyze the biomechanical behavior of aneurysmal specimens found at autopsy, comparing them with normal diameter aortas removed from age-matched donors. METHODS: Thirty-eight human aortas (30 normal aortas; 8 infrarenal abdominal aortic aneurysms) were harvested during autopsy. An apparatus was built with a digital gauge, plastic tray, connections, and hoses that conducted fluid (air) from a pump through the system. Specimens were dissected, and a flexible balloon was introduced in each of them to avoid leakage. The specimens were fastened on the test tray, and activation of the air pump enhanced system pressure up to their rupture. RESULTS: All 8 aneurysms and all 30 normal aortas specimens evolved to rupture under inflation pressures above 590 mm Hg (mean ± standard deviation = 1,035 ± 375 mm Hg) and 840 mm Hg (mean ± SD = 1,405 ± 342 mm Hg), respectively. In the aneurysm group, 25% of specimens did not rupture in their most dilated region. Percentage of increment in diameter was higher in normal aortas (mean ± SD = 0.2106 ± 0.144) than in aneurysms (mean ± SD = 0.093 ± 0.070). CONCLUSIONS: In the present experiment, unruptured infrarenal abdominal aortic aneurysms could support high pressures nearly as much as nonaneurysmal abdominal aortas. In some specimens, the most dilated part of the aneurysm was not the most vulnerable under pressure. Normal aortas presented higher elasticity than aneurysms.


Assuntos
Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Ruptura Aórtica/patologia , Pressão Arterial , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/fisiopatologia , Ruptura Aórtica/etiologia , Ruptura Aórtica/fisiopatologia , Autopsia , Estudos de Casos e Controles , Dilatação Patológica , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Vasc Res ; 52(4): 257-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26799837

RESUMO

INTRODUCTION: The biomechanical failure properties and histological composition of the human nonaneurysmal aorta were studied. METHODS: Twenty-six human aortas were harvested from fresh cadavers at autopsy. A total of 153 circumferentially oriented strips were obtained from the aortas for biomechanical and histological studies. RESULTS: The failure load (6.18 ± 2.03 vs. 4.85 ± 2.04 N; p = 0.001), failure tension (19.88 ± 9.05 vs. 14.53 ± 7 N/cm; p = 0.001), failure strain (0.66 ± 0.31 vs. 0.49 ± 0.25; p = 0.003) and amount of elastic fibers (19.39 ± 15.57 vs. 14.06 ± 9.5%; p = 0.011) were all significantly higher for the thoracic than the abdominal aorta. There was a significant negative correlation between age and failure load (R = -0.35; p < 0.0001), failure stress (R = -0.63; p < 0.0001), failure tension (R = -0.52; p < 0.0001) and failure strain (R = -0.8; p < 0.0001). Male aortas had a higher failure load and failure tension than female aortas. CONCLUSION: The thoracic aorta has a higher strength and elasticity than the abdominal aorta. The elderly have weaker and stiffer aortas than the young. Male aortas are stronger than female aortas.


Assuntos
Envelhecimento , Aorta Abdominal/fisiopatologia , Aorta Torácica/fisiopatologia , Rigidez Vascular , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Aorta Abdominal/patologia , Aorta Torácica/patologia , Autopsia , Fenômenos Biomecânicos , Tecido Elástico/patologia , Tecido Elástico/fisiopatologia , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Estresse Mecânico
5.
Langmuir ; 30(19): 5481-7, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24787894

RESUMO

Cell culture systems for studying the combined effects of matrix proteins and mechanical forces on the behavior of soft tissue cells have not been well developed. Here, we describe a new biomimetic cell culture system that allows for the study of mixtures of matrix proteins while controlling mechanical stiffness in a range that is physiological for soft tissues. This system consists of layer-by-layer (LbL)-assembled films of native matrix proteins atop mechanically tunable soft supports. We used hepatic stellate cells, which differentiate to myofibroblasts in liver fibrosis, for proof-of-concept studies. By culturing cells on collagen and lumican LbL-modified hydrogels, we demonstrate that this system is noncytotoxic and offers a valid control substrate, that the hydrogel determines the overall system mechanics, and that the addition of lumican to collagen influences the stellate cell phenotype. LbL-modified hydrogels offer the potential to study the influence of complex environmental factors on soft-tissue cells in culture.


Assuntos
Técnicas de Cultura de Células/métodos , Miofibroblastos/citologia , Animais , Humanos , Hidrogéis
6.
Chem Eng J ; 189-190: 237-243, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22539917

RESUMO

The description and operation of a novel, hybrid spouted vessel/fixed bed filter system for the removal of arsenic from water are presented. The system utilizes zero-valent iron (ZVI) particles circulating in a spouted vessel that continuously generates active colloidal iron corrosion products via the "self-polishing" action between ZVI source particles rolling in the moving bed that forms on the conical bottom of the spouted vessel. This action also serves as a "surface renewal" mechanism for the particles that provides for maximum utilization of the ZVI material. (Results of batch experiments conducted to examine this mechanism are also presented.) The colloidal material produced in this fashion is continuously captured and concentrated in a fixed bed filter located within the spouted vessel reservoir wherein arsenic complexation occurs. It is demonstrated that this system is very effective for arsenic removal in the microgram per liter arsenic concentration (i.e., drinking water treatment) range, reducing 100 µg/L of arsenic to below detectable levels (≪10 µg/L) in less than an hour.A mechanistic analysis of arsenic behavior in the system is presented, identifying the principal components of the population of active colloidal material for arsenic removal that explains the experimental observations and working principles of the system. It is concluded that the apparent kinetic behavior of arsenic in systems where colloidal (i.e., micro/nano) iron corrosion products are dominant can be complex and may not be explained by simple first or zeroth order kinetics.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...