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1.
J Neurooncol ; 162(1): 15-23, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36853489

RESUMO

PURPSOSE: Cerebral radiation necrosis (RN) is often a delayed phenomenon occurring several months to years after the completion of radiation treatment. Differentiating RN from tumor recurrence presents a diagnostic challenge on standard MRI. To date, no evidence-based guidelines exist regarding imaging modalities best suited for this purpose. We aim to review the current literature and perform a diagnostic meta-analysis comparing various imaging modalities that have been studied to differentiate tumor recurrence and RN. METHODS: A systematic search adherent to PRISMA guidelines was performed using Scopus, PubMed/MEDLINE, and Embase. Pooled sensitivities and specificities were determined using a random-effects or fixed-effects proportional meta-analysis based on heterogeneity. Using diagnostic odds ratios, a diagnostic frequentist random-effects network meta-analysis was performed, and studies were ranked using P-score hierarchical ranking. RESULTS: The analysis included 127 studies with a total of 220 imaging datasets, including the following imaging modalities: MRI (n = 10), MR Spectroscopy (MRS) (n = 28), dynamic contrast-enhanced MRI (n = 7), dynamic susceptibility contrast MRI (n = 36), MR arterial spin labeling (n = 5), diffusion-weighted imaging (n = 13), diffusion tensor imaging (DTI) (n = 2), PET (n = 89), and single photon emission computed tomography (SPECT) (n = 30). MRS had the highest pooled sensitivity (90.7%). DTI had the highest pooled specificity (90.5%). Our hierarchical ranking ranked SPECT and MRS as most preferable, and MRI was ranked as least preferable. CONCLUSION: These findings suggest SPECT and MRS carry greater utility than standard MRI in distinguishing RN from tumor recurrence.


Assuntos
Imagem de Tensor de Difusão , Recidiva Local de Neoplasia , Humanos , Imageamento por Ressonância Magnética/métodos , Necrose/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/métodos
2.
Health Econ ; 29(7): 748-765, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32301244

RESUMO

This paper offers an approach to assessing quality of life, based on Sen's (1985) theory, which it uses to understand loss in quality of life due to mobility impairment. Specifically, it provides a novel theoretical analysis that is able to account for the possibility that some functionings may increase when a person's capabilities decrease, if substitution effects are large enough. We then develop new data consistent with our theoretical framework that permits comparison of quality of life between those with a disability (mobility impairment) and those without. Empirical results show that mobility impairment has widespread rather than concentrated impacts on capabilities and is associated with high psychological costs. We also find evidence that a small number of functionings are higher for those with a disability, as our theory allows. The paper concludes by discussing possible implications for policy and health assessment methods.


Assuntos
Pessoas com Deficiência , Qualidade de Vida , Nível de Saúde , Humanos , Renda
3.
Lancet ; 391 Suppl 2: S37, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29553436

RESUMO

BACKGROUND: Siege, a process of political domination aimed at isolating an entire population, is a unique threat to health-care provision. The aim of this study was to qualitatively examine the effects of the Israeli siege on the practices and systems that underlie health in the Gaza Strip. METHODS: Data were from participant observation between 2009 and 2017, including 20 interviews with doctors and health administrators in non-governmental organisations (NGO), government, and UN sectors. All participants were provided with a description of the study and provided written consent to participate. The study was approved through the Human Subjects Review process at Bucknell University and the University of Washington. The data were analysed using a critical political economic framework, based on the concepts of primitive accumulation, accumulation by dispossession, surplus populations, and de-development. These analytical frames are further developed to interpret neoliberal trends in health-care systems organising and financing as they apply in the distorted social and economic context of siege. FINDINGS: The elimination of political sovereignty through the twin processes of occupation and siege are the primary impediments to the successful promotion of public health in the Gaza Strip. Findings indicate that siege impinges on effective health-care provision by withholding materials and resources and undermining the health care at a systems level. These strains pose considerable threats to health care, within the ministry of health and among other entities in the Gaza Strip that deliver care. Gazan society is divested of the underpinnings necessary for a well functioning sovereign health-care infrastructure. Instead of a self-governing, independent system, this analysis reveals a system that is comprised of captive clients who are entirely dependent on Israel, international bodies, and the aid industry for goods and services, with no means of independent development. INTERPRETATION: The siege represents a totalising social determinant of public health in the Gaza Strip, and it has significant and deliberate deleterious effects on the provision of medical care and exacerbates problems in overstretched medical services. These findings point to the importance of foregrounding the geopolitical context for analysis of medical service delivery within conflict settings. The data indicate formative trends in health-care provision in the Gaza Strip. Although the siege creates a seemingly unique economic context for analysis of health-care provision, critical analyses that deconstruct the depredations of neoliberalism in the health-care setting provide a useful framework for analysis of the failings of the health-care sector. Indeed, health-care providers are in an impossible position of attempting to provide quality care without the ability to coordinate with their colleagues in other sectors, and without substantial support from the international community. The final analysis also highlights the importance of advocating for sovereignty and self-determination as related to health systems, and it suggests that successful health-care provision is impossible without a strong analysis of the political and economic context. FUNDING: Bucknell University.

4.
Environ Res ; 144(Pt B): 15-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26597639

RESUMO

An integrated methodology, based on linking Bayesian belief networks (BBN) with GIS, is proposed for combining available evidence to help forest managers evaluate implications and trade-offs between forest production and conservation measures to preserve biodiversity in forested habitats. A Bayesian belief network is a probabilistic graphical model that represents variables and their dependencies through specifying probabilistic relationships. In spatially explicit decision problems where it is difficult to choose appropriate combinations of interventions, the proposed integration of a BBN with GIS helped to facilitate shared understanding of the human-landscape relationships, while fostering collective management that can be incorporated into landscape planning processes. Trades-offs become more and more relevant in these landscape contexts where the participation of many and varied stakeholder groups is indispensable. With these challenges in mind, our integrated approach incorporates GIS-based data with expert knowledge to consider two different land use interests - biodiversity value for conservation and timber production potential - with the focus on a complex mountain landscape in the French Alps. The spatial models produced provided different alternatives of suitable sites that can be used by policy makers in order to support conservation priorities while addressing management options. The approach provided provide a common reasoning language among different experts from different backgrounds while helped to identify spatially explicit conflictive areas.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Tomada de Decisões , Ecologia/métodos , Florestas , Teorema de Bayes , Conservação dos Recursos Naturais/economia , Ecologia/economia , França , Técnicas de Planejamento
6.
J Gastrointest Cancer ; 54(3): 846-854, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36251211

RESUMO

PURPOSE: Historically, reported incidence of brain metastasis secondary to esophageal carcinoma is low. We sought to determine the incidence of brain metastasis in a contemporary cohort of patients with carcinoma of the esophagus. METHODS: Data from patients with localized esophageal carcinoma prospectively enrolled on three curative intent Alliance treatment trials (N0044, N0342, N044E) were reviewed including time to diagnosis of first progression event (brain versus other site) and overall survival. RESULTS: Eighty-five patients comprised the cohort of which 85% were male and 86% had adenocarcinoma primary tumor histology. Thirty-nine of the 85 patients had documented progression to any site, and of those, brain metastasis occurred as the first event in 15% (6 of 39). Adenocarcinoma was the primary histology in all 6 patients and tumor grade was high (3 or 4) in 5 of the 6 patients (one not documented). Median time to brain metastasis (9.6 months) versus non-brain metastasis (12.4 months) and median survival after first progression (5.4 months versus 8.1 months, respectively) were not statistically different. CONCLUSION: In this prospective cohort of patients with esophageal carcinoma, those with high-grade adenocarcinoma appear to have a higher incidence of brain metastasis than historically reported. The pattern of brain metastases corroborates recent findings in terms of incidence, predominance of adenocarcinoma primary tumor histology, timing after diagnosis, and overall survival. Further study to confirm these findings, as well as the value of baseline, restaging and follow-up cranial imaging for brain metastasis is recommended. GOV IDENTIFIERS: NCT00022139 (NCCTG N0044), NCT00100945 (NCCTG N0342), and NCT00100945 (NCCTG N044E).


Assuntos
Adenocarcinoma , Neoplasias Encefálicas , Carcinoma , Neoplasias Esofágicas , Humanos , Masculino , Feminino , Incidência , Estudos Prospectivos , Adenocarcinoma/epidemiologia , Adenocarcinoma/terapia , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/secundário
7.
Insects ; 14(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36975947

RESUMO

After resistance is first detected, continued resistance monitoring can inform decisions on how to effectively manage resistant populations. We monitored for resistance to Cry1Ac (2018 and 2019) and Cry2Ab2 (2019) from southeastern USA populations of Helicoverpa zea. We collected larvae from various plant hosts, sib-mated the adults, and tested neonates using diet-overlay bioassays and compared them to susceptible populations for resistance estimates. We also compared LC50 values with larval survival, weight and larval inhibition at the highest dose tested using regression, and found that LC50 values were negatively correlated with survival for both proteins. Finally, we compared resistance rations between Cry1Ac and Cry2Ab2 during 2019. Some populations were resistant to Cry1Ac, and most were resistant to CryAb2; Cry1Ac resistance ratios were lower than Cry2Ab2 during 2019. Survival was positively correlated with larval weight inhibition for Cry2Ab. This contrasts with other studies in both the mid-southern and southeastern USA, where resistance to Cry1Ac, Cry1A.105, and Cry2Ab2 increased over time and was found in a majority of populations. This indicates that cotton expressing Cry proteins in the southeastern USA was at variable risk for damage in this region.

8.
Inorg Chem ; 48(12): 5216-23, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19432467

RESUMO

Neutron diffraction experiments and Korringa-Kohn-Rostoker with coherent potential approximation electronic band structure calculations as well as electrical resistivity measurements have been performed on polycrystalline Mo(3-x)Ru(x)Sb(7) samples for 0 < or = x < or = 1. Neutron diffraction studies have been undertaken at room temperature and extended down to 4 K to get a better understanding of the crystalline structure modifications as the Ru content increases. Both structural and chemical characterizations have unambiguously revealed a solubility limit of the Ru atoms close to 0.8. Electronic band structure calculations have provided theoretical evidence of a progressive transition from a metalliclike state (x = 0) toward a semiconducting-like character as x = 1 is approached, although the solubility limit of Ru precludes a crossover to a semiconducting behavior. The theoretical prediction has been experimentally confirmed by low-temperature electrical resistivity measurements from 2 up to 350 K.

9.
Heart Surg Forum ; 12(1): E59-60, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19233769

RESUMO

Elevated pulmonary vascular resistance in a transplantation candidate should be viewed as potentially reversible, and there are several options for therapy. We describe a young patient with congenital restrictive cardiomyopathy and a markedly elevated pulmonary artery pressure. The patient underwent successful orthotopic heart transplantation after pharmacologic lowering of the pulmonary artery pressure with a new drug combination of milrinone and nesiritide. The length of therapy can be extended to 3 days to allow for determining the pulmonary vascular responsiveness.


Assuntos
Cardiomiopatias/complicações , Cardiomiopatias/cirurgia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/prevenção & controle , Transplante de Coração/métodos , Hipertensão/complicações , Hipertensão/cirurgia , Síndrome de Noonan/cirurgia , Adolescente , Contraindicações , Humanos , Masculino , Síndrome de Noonan/complicações , Resultado do Tratamento
10.
J Strength Cond Res ; 23(9): 2555-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19910819

RESUMO

The purpose of this study was to examine changes in various aerobic and anaerobic physical performance measures in male National Collegiate Athletic Association (NCAA) Division III soccer players during the competitive soccer season. Twelve starters of the men's soccer team (mean +/- SD; age = 20.0 +/- 0.9 years, height = 175.7 +/- 8.1 cm, body mass = 73.9 +/- 11.00 kg, body mass index [BMI] 24.0 +/- 3.0 kg.m2, and percent body fat = 10.6 +/- 5.4%) were tested at the beginning (PRS) and the end (POS) of the collegiate soccer season. Each experimental trial included a maximal aerobic capacity test (VO2max); 10-, 30-, and 40-m sprints; pro-agility test; and the Wingate anaerobic power test (WAnT). From PRS to POS, VO2max significantly increased (51.05 +/- 5.97 vs. 54.64 +/- 4.90 ml.kg-1.min-1), and the 10- and 30-m sprint were significantly lower (2.03 +/- 0.15 vs. 1.96 +/- 0.11 seconds and 4.72 +/- 0.26 vs. 4.51 +/- 0.24 seconds, respectively). Anthropometric measures, 40-m sprint, pro-agility test, and WAnT were not significantly different between PRS and POS. The results of this study indicate that NCAA Division III male soccer players appear to improve aerobic and anaerobic performance measures during the competitive soccer season. It is arguable that these performance improvements may represent a poor preseason conditioning level that may result in a competitive disadvantage during the early stages of the season. An ongoing process of recruiting better-quality players that may closely follow the off-season training regimen may partially remedy this problem.


Assuntos
Limiar Anaeróbio/fisiologia , Desempenho Atlético/fisiologia , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Estações do Ano , Futebol/fisiologia , Adulto , Antropometria , Composição Corporal , Índice de Massa Corporal , Comportamento Competitivo , Teste de Esforço , Tolerância ao Exercício/fisiologia , Humanos , Masculino , Fadiga Muscular/fisiologia , North Carolina , Aptidão Física , Dobras Cutâneas , Estados Unidos , Universidades
11.
Tex Heart Inst J ; 34(4): 463-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18172532

RESUMO

Operative methods for repairing ascending aortic dissections and for implanting left ventricular assist systems have been thoroughly presented in the medical literature. Only a few reports, however, describe the concomitant performance of these procedures in 1 patient. We report the repair of an acute ascending aortic dissection with simultaneous placement of a long-term left ventricular assist system. One week earlier, the patient had undergone emergent coronary artery bypass grafting and short-term postcardiotomy ventricular assistance when he could not be weaned from cardiopulmonary bypass. By creating a graft-to-graft anastomosis on the bench during cooling of the patient on cardiopulmonary bypass, we were able to shorten to 21 minutes the period of hypothermic circulatory arrest required during ascending aortic dissection repair. The procedures were completed successfully. However, the patient developed pneumonia and sepsis during his extended hospital stay and died of multiorgan failure 5 weeks postoperatively.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Coração Auxiliar , Implantação de Prótese/métodos , Choque Cardiogênico/cirurgia , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico , Ecocardiografia Transesofagiana , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Choque Cardiogênico/etiologia
12.
Psychopharmacology (Berl) ; 186(4): 612-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16598454

RESUMO

RATIONALE: Enhanced reinforcing effects of nicotine during adolescence appear to contribute to the rapid development of dependence in this age group. However, the contribution of nicotine withdrawal to dependence in adolescents is unclear. OBJECTIVE: We compared motivational and somatic signs of nicotine withdrawal in adolescent and adult rats. MATERIALS AND METHODS: In experiment 1, motivational signs of nicotine withdrawal were compared using intracranial self-stimulation procedures after administration of mecamylamine (1.5 mg/kg, i.p.) in adolescent and adult rats made dependent on nicotine (9 mg/kg/day). Somatic signs of withdrawal were compared in two experiments using various doses of nicotine (adolescent doses: 0, 1.6, 3.2, 4.7 mg/kg/day; adult doses: 0, 1, 2.1, 3.2 mg/kg/day, expressed as nicotine base) to produce dependence and one dose of mecamylamine (1.5 mg/kg, i.p.) to precipitate withdrawal (experiment 2) and in a subsequent experiment, using various doses of mecamylamine (0, 0.75, 1.5, 3.0 mg/kg, i.p.) to precipitate withdrawal and a dose of nicotine (adolescent dose: 4.7 mg/kg/day; adult dose: 3.2 mg/kg/day) that produced equivalent nicotine blood levels in these age groups (experiment 3). RESULTS: Adolescents did not display the decreases in brain reward function observed in adults experiencing withdrawal, and displayed fewer somatic signs of nicotine withdrawal relative to adults regardless of the dosing procedure used. CONCLUSION: The negative effects of nicotine withdrawal are lower during adolescence relative to later periods of development. Both the enhanced rewarding effects and the diminished nicotine withdrawal likely contribute to the rapid development of nicotine use during adolescence.


Assuntos
Nicotina/efeitos adversos , Síndrome de Abstinência a Substâncias/psicologia , Tabagismo/psicologia , Fatores Etários , Animais , Comportamento Animal/efeitos dos fármacos , Cotinina/sangue , Relação Dose-Resposta a Droga , Masculino , Mecamilamina/farmacologia , Nicotina/antagonistas & inibidores , Nicotina/sangue , Antagonistas Nicotínicos/farmacologia , Ratos , Ratos Sprague-Dawley , Recompensa , Autoestimulação , Limiar Sensorial/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/sangue
13.
Pest Manag Sci ; 72(10): 1934-45, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26775623

RESUMO

BACKGROUND: Over the past two decades, neonicotinoid seed treatments have become the primary method to manage tobacco thrips, Frankliniella fusca Hinds, on seedling cotton. Because this insect is highly polyphagous and the window of insecticide exposure is short, neonicotinoid resistance was expected to pose a minimal risk. However, reports of higher than expected F. fusca seedling damage in seed-treated cotton fields throughout the Mid-South and Southeast US production regions suggested neonicotinoid resistance had developed. To document this change, F. fusca populations from 86 different locations in the eastern United States were assayed in 2014 and 2015 for imidacloprid and thiamethoxam resistance to determine the extent of the issue in the region. RESULTS: Approximately 57 and 65% of the F. fusca populations surveyed had reduced imidacloprid and thiamethoxam sensitivity respectively. Survivorship in diagnostic bioassays was significantly different at both the state and regional scales. Multiple-dose bioassays conducted on 37 of the populations documented up to 55- and 39-fold resistance ratios for imidacloprid and thiamethoxam respectively. CONCLUSION: Estimates of neonicotinoid resistance indicate an emerging issue for management of F. fusca in the eastern United States. Significant variation in survivorship within states and regions indicated that finer-scale surveys were needed to determine factors (genetic, insecticide use) driving resistance evolution. © 2016 Society of Chemical Industry.


Assuntos
Resistência a Inseticidas , Inseticidas , Tisanópteros/genética , Animais , Gossypium/parasitologia , Imidazóis , Neonicotinoides , Nitrocompostos , Oxazinas , Sementes/parasitologia , Tiametoxam , Tiazóis , Estados Unidos
14.
J Clin Oncol ; 21(10): 2026-33, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12743158

RESUMO

PURPOSE: Evaluation of pretreatment factors to identify children at high risk for relapse after combined-modality therapy for Hodgkin's disease. PATIENTS AND METHODS: From 1990 to 2000, 328 pediatric patients with clinical stage I to IV Hodgkin's disease were treated with chemotherapy and low-dose involved-field radiotherapy on prospective, collaborative, risk-adapted protocols at three institutions. Pretreatment factors were analyzed by univariate and multivariate analysis for prognostic significance for 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: With a median follow-up of 59 months (range, 8 to 125 months), the 5-year DFS and OS for all patients were 83% and 93%, respectively. Several factors were associated with inferior DFS and OS by univariate analysis. By multivariate analysis, male sex; stage IIB, IIIB, or IV disease; bulky mediastinal disease; WBC more than 13.5 x 10(3)/mm3; and hemoglobin less than 11.0 g/dL were significant for inferior DFS. A prognostic index was developed incorporating the five significant factors from the multivariate analysis, assigning each a score of 1. The 5-year DFS and OS for children with a prognostic score of 0 to 1 were 94% and 99%; score 2, 85% and 96%; score 3, 71% and 92%; and score 4 or 5, 49% and 72%, respectively. There was a significant difference in DFS among each of these groups, with significantly worse OS in those with a score of 4 to 5. CONCLUSION: A prognostic index that was based on five pretreatment factors correlated with inferior DFS by multivariate analysis stratified patients by outcome; this may be useful in assigning children with Hodgkin's disease to risk-adapted therapy.


Assuntos
Doença de Hodgkin/terapia , Recidiva Local de Neoplasia/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Humanos , Modelos Logísticos , Masculino , Estudos Multicêntricos como Assunto , Terapia Neoadjuvante , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Análise de Sobrevida , Estados Unidos
15.
Tree Physiol ; 25(7): 915-27, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15870058

RESUMO

Process-based forest models generally have many parameters, multiple outputs of interest and a small underlying empirical database. These characteristics hamper parameterization. Bayesian calibration offers a solution to the calibration problem because it applies to models of any type or size. It provides parameter estimates, with measures of uncertainty and correlation among the parameters. The procedure begins by quantifying the uncertainty about parameter values in the form of a prior probability distribution. Then data on the output variables are used to update the parameter distribution by means of Bayes' Theorem. This yields a posterior calibrated distribution for the parameters, which can be summarized in the form of a mean vector and variance matrix. The predictive uncertainty of the model can be quantified by running it with different parameter settings, sampled from the posterior distribution. In a further step, one may evaluate the posterior probability of the model itself (rather than that of the parameters) and compare that against the probability of other models, to aid in model selection or improvement. Bayesian calibration of process-based models cannot be performed analytically, so the posterior parameter distribution must be approximated in the form of a representative sample of parameter values. This can be achieved by means of Markov Chain Monte Carlo simulation, which is suitable for process-based models because of its simplicity and because it does not require advance knowledge of the shape of the posterior distribution. Despite the suitability of Bayesian calibration, the technique has rarely been used in forestry research. We introduce the method, using the example of a typical forest model. Further, we show that reductions in parameter uncertainty, and thus in output uncertainty, can be effected by increasing the variety of data, increasing the accuracy of measurements and increasing the length of time series.


Assuntos
Modelos Biológicos , Árvores/fisiologia , Algoritmos , Teorema de Bayes , Calibragem , Funções Verossimilhança , Cadeias de Markov , Método de Monte Carlo , Incerteza
16.
Soc Sci Med ; 146: 332-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26603311

RESUMO

Siege, a process of political domination aimed at isolating an entire population, represents a unique threat to healthcare provision. This study is a qualitative examination of the impacts of siege on the practices and systems that underlie health in Gaza. Data are from participant observation conducted over a period of six years (2009-2014), along over 20 interviews with doctors and health administrators in the Non-Governmental Organisation (NGO), Governmental, and United Nations sectors. Analyses were informed by two connected theories. First, the theory of surplus population was used, an idea that builds on Marx's conception of primitive accumulation and Harvey's accumulation by dispossession. Second, Roy's theory of de-development was used, particularly as it is connected to neoliberal trends in healthcare systems organizing and financing. Findings indicate that siege impinges on effective healthcare provision through two central, intertwined processes: withholding materials and resources and undermining healthcare at a systems level. These strains pose considerable threats to healthcare, particularly within the Ministry of Health but also within and among other entities in Gaza that deliver care. The strategies of de-development described by participants reflect the ways the population that is codified as a surplus population. Gazan society is continually divested of any of the underpinnings necessary for a well-functioning sovereign health care infrastructure. Instead of a self-governing, independent system, this analysis of health care structures in Gaza reveals a system that is continually at risk of being comprised entirely of captive consumers who are entirely dependent on Israel, international bodies, and the aid industry for goods and services. This study points to the importance of foregrounding the geopolitical context for analysis of medical service delivery within conflict settings. Findings also highlight the importance of advocating for sovereignty and self-determination as related to health systems.


Assuntos
Conflitos Armados , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Política , Feminino , Violação de Direitos Humanos , Humanos , Estudos Interdisciplinares , Israel , Masculino , Oriente Médio , Alocação de Recursos
17.
Biomaterials ; 25(11): 2205-13, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14741636

RESUMO

X-ray and time of flight neutron diffraction data, FTIR and MAS-NMR spectra, and ICP-AES and carbonate analyses have been collected from a sodium-containing carbonate apatite (CO(3) content 12.5(7)wt%). A structural model based on Holly Springs hydroxyapatite without CO(3)(2-) ions showed an apparent reduction in the PO(4) tetrahedral volume which is ascribed to CO(3)(2-) replacing PO(4)(3-) ions in the lattice. Four structural models from the literature with the CO(3)(2-) ion explicitly modelled were fitted to the neutron diffraction data by the Rietveld method. The best fit was obtained with the CO(3)(2-) ion in disorder between the mirror symmetry related faces of a vacant PO(4)(3-) site and with the normal to the plane of the CO(3)(2-) ion at approximately 30 degrees to the c-axis. This angle is consistent with results from previous polarised IR measurements on single crystals of francolite (a fluorocarbonate apatite) and human dental enamel. Further refinement of the model revealed a hitherto unknown atom site close to the unit cell origin, (possibly a water molecule). The refined hexagonal unit cell parameters from the neutron diffraction data were a=9.3446(3)A and c=6.9199(4)A.


Assuntos
Apatitas/química , Materiais Biocompatíveis/química , Teste de Materiais/métodos , Modelos Químicos , Modelos Moleculares , Difração de Nêutrons/métodos , Apatitas/análise , Carbonatos/química , Precipitação Química , Simulação por Computador , Cristalografia , Conformação Molecular
18.
Physiol Plant ; 111(3): 283-290, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11240911

RESUMO

Pyruvate kinase (PK, EC 2.7.1.40) was partially purified from the plant cytosolic fraction of N2-fixing soybean (Glycine max [L.] Merr.) root nodules. The partially purified PK preparation was completely free of contamination by phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31), the other major phosphoenolpyruvate (PEP)-utilizing enzyme in legume root nodules. Latency experiments with sonicated nodule extracts showed that Bradyrhizobium japonicum bacteroids do not express either PK or PEPC activity in symbiosis. In contrast, free-living B. japonicum bacteria expressed PK activity, but not PEPC activity. Antibodies specific for the cytosolic isoform of PK from castor bean endosperm cross-reacted with a 52-kDa polypeptide in the partially purified PK preparation. At the optimal assay pH (pH 8.0 for PEPC and pH 6.9 for PK) and in the absence of malate, PEPC activity in crude nodule extracts was 2.6 times the corresponding PK activity. This would tend to favour PEP metabolism by PEPC over PEP metabolism by PK. However, at pH 7.0 in the presence of 5 mM malate, PEPC activity was strongly inhibited, but PK activity was unaffected. Thus, we propose that PK and PEPC activity in legume root nodules may be coordinately regulated by fluctuations in malate concentration in the plant cytosolic fraction of the bacteroid-containing cells. Reduced uptake of malate by the bacteroids, as a result of reduced rates of N2 fixation, may favour PEP metabolism by PK over PEP metabolism by PEPC.

19.
Oecologia ; 62(1): 102-109, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28310747

RESUMO

The introduced reindeer of South Georgia have had a serious impact on the vegetation throughout the range of three populations on the island. Exclosure experiments in areas where the reindeer were introduced have resulted in a dramatic change in the composition of the protected vegetation. Poa flabellata (the major winter food) and Acaena magellanica (a major summer food) have recovered to their former status inside the exclosures, while Deschampsia antarctia and the introduced grass Poa annua tolerate grazing and trampling and have spread over the grazed areas. Festuca contracta and Rostkovia magellanica are not eaten by the reindeer. Trampling has resulted in a high proportion of bare soil and peat in sites freely accessible to reindeer. However, the changes in the vegetation have not had such a significant effect on the associated invertebrate fauna. Thus in grazed and protected areas the faunistic composition is qualitatively similar, although there are quantitative differences, and some of the trends can probably be attributed to the presence of the reindeer. Compared with reindeer-free areas, the abundance of the perimylopid beetle Hydromedion sparsutum (a major primary decomposer) is reduced. The frequency of their egg parasite Notomymar aptenosoma (Hymenoptera, Mymaridae) increases. Consequently the ratio of perimylopoids to mymarids found in pitfall traps shifts from 1:0.01 (ungrazed areas) to 1:0.54 (grazed areas). Also the frequency of sciarids was found to be higher in reindeer areas. The larvae of these probably introduced gnats do not play a role in the natural terrestrial ecosystem of South Georgia, but in reindeer areas they appear to establish larger populations because they are able to live deeper in the soil and in hardened substrates. There is also a shift in the ratio between Collembola (major prey) to spiders from 1:1.3 (ungrazed areas) to 1:0.82 (grazed areas), for animals collected in pitfall traps. This may be a result of the trampling effect of the reindeer.

20.
Nanomedicine (Lond) ; 8(10): 1577-86, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23432340

RESUMO

AIM: The aim of this study was to investigate in vitro the utility of biologically compatible, nontoxic and cell-specific targetable hydrogel nanoparticles (NPs), which have Coomassie® Brilliant Blue G dye (Sigma-Aldrich, MO, USA) covalently linked into their polyacrylamide matrix, as candidates for photothermal therapy (PTT) of cancer cells. MATERIALS & METHODS: Hydrogel NPs with Coomassie Brilliant Blue G dye covalently linked into their polyacrylamide matrix were fabricated using a reverse micelle microemulsion polymerization method and were found to be 80-95 nm in diameter, with an absorbance value of 0.52. PTT-induced hyperthermia/thermolysis was achieved at 37°C using an inexpensive, portable, light-emitting diode array light source (590 nm, 25 mW/cm(2)). RESULTS & CONCLUSION: Hydrogel NPs with Coomassie Brilliant Blue G dye linked into their polyacrylamide matrix are effective in causing PTT-induced thermolysis in immortalized human cervical cancer cell line (HeLa) cells for varying NP concentrations and treatment times. These multifunctional particles have previously been used in cancer studies to enable delineation, for glioma surgery and in photoacoustic imaging studies. The addition of the PTT function would enable a three-pronged theranostic approach to cancer medicine, such as guided tumor surgery with intra-operative photoacoustic imaging and intra-operative PTT.


Assuntos
Hidrogéis/administração & dosagem , Nanopartículas/administração & dosagem , Fototerapia , Neoplasias do Colo do Útero/terapia , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/química , Feminino , Células HeLa , Humanos , Hidrogéis/química , Nanopartículas/química , Corantes de Rosanilina/administração & dosagem , Corantes de Rosanilina/química , Neoplasias do Colo do Útero/patologia
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