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Neighbourhood greenness or vegetative presence has been associated with indicators of health and well-being, but its relationship to depression in older adults has been less studied. Understanding the role of environmental factors in depression may inform and complement traditional depression interventions, including both prevention and treatment.
This study examines the relationship between neighbourhood greenness and depression diagnoses among older adults in Miami-Dade County, Florida, USA.
Analyses examined 249 405 beneficiaries enrolled in Medicare, a USA federal health insurance programme for older adults. Participants were 65 years and older, living in the same Miami location across 2 years (2010–2011). Multilevel analyses assessed the relationship between neighbourhood greenness, assessed by average block-level normalised difference vegetative index via satellite imagery, and depression diagnosis using USA Medicare claims data. Covariates were individual age, gender, race/ethnicity, number of comorbid health conditions and neighbourhood median household income.
Over 9% of beneficiaries had a depression diagnosis. Higher levels of greenness were associated with lower odds of depression, even after adjusting for demographics and health comorbidities. When compared with individuals residing in the lowest tertile of greenness, individuals from the middle tertile (medium greenness) had 8% lower odds of depression (odds ratio 0.92; 95% CI 0.88, 0.96; P = 0.0004) and those from the high tertile (high greenness) had 16% lower odds of depression (odds ratio 0.84; 95% CI 0.79, 0.88; P < 0.0001).
Higher levels of greenness may reduce depression odds among older adults. Increasing greenery – even to moderate levels – may enhance individual-level approaches to promoting wellness.
Composites from carbon nanotubes and polymers have been synthesized and studied. The composites were obtained joining carbon nanotubes with polymethyl methacrylate, nylon-6 and polystyrene. The materials were observed through scanning electron microscopy to evaluate the carbon nanotubes dispersion in the polymeric matrices. FTIR and Raman spectroscopies were used to analyze the interactions among functionalized and non-functionalized multiwalled carbon nanotubes and polymers, demonstrating affinity and peculiar spectra behaviors for each composite with different carbon nanotubes loads.
The acidity of SBA-15 was tuned with the incorporation of Al+3, Ti+4, and –PrSO3H groups through sol–gel, employing molar ratios of Si/M = 10 (M = Al, Ti) and Si/S = 10. This results in mesoporous materials with the typical hexagonal structure of SBA-15, large surface areas, and great pore diameter. The incorporation of Al+3 and Ti+4 mainly leads to catalysts with both Brönsted and Lewis acid sites. The addition of sulfonic groups to these samples enhanced their surface acidity, creating preferentially Brönsted acid sites. Among the evaluated catalysts, the SBA-15-SO3H showed the highest catalytic activity, which was related to the high concentration of Lewis acid sites, and a remarkable resistance to deactivation, probably due to its low hydrophilicity. A first order kinetic equation fits well the experimental data and an activation energy of 31.5 kJ/mol similar to other reports for this reaction was calculated for the SBA-15-SO3H catalyst.
PA6 and PMMA polymers with different MWCNTs addition (5, 7 and 9 wt %) were synthetized through casting solution, resulting in improvement properties in contrast to pristine polymers. SEM images showed the MWCNTs embedded into polymeric matrices. D, G and G´ bands of MWCNTs were confirmed by Raman spectroscopy and functional groups observed in both nanocomposites by FTIR demonstrated a strong interaction. A significant increasing in electrical conductivity and microhardness was observed in all the nanocomposites. Major microhardness values were obtained in MWCNTs/PA6 (50 HV) however the MWCNTs/PMMA nanocomposites showed the highest electrical conductivity value (6.4×10-4 S/cm).
In the present study, aiming to control the setting reaction and to increase the strength of hydroxyapatite-based biocements, gelatin, citric acid and malonic acid, and combinations of them, were used as binders. The mechanical strength of the developed biocements was evaluated after 1 to 15 days of exposure (aging) to air with 100% relative humidity at 37-40 °C. Especially for the case of gelatin, the mechanical properties of the biocements increased as a function of aging time in the humid environment. In this case, the standard compressive strength increased from ∼19 to ∼40 MPa, while the diametral compressive strength increased from ∼2 to ∼12 MPa, between day 1 and day 15 of aging. These values are similar to those reported in the past for HAp-containing biocements added with a variety of organic or inorganic binders. However, the resulting setting times were too long. Thus, it was proposed that crosslinking of gelatin by a suitable chemical agent during the application of the prepared HAp-based biocements could be a potential way to control their handling and setting characteristics, while preserving their good mechanical properties, good biocompatibility, and good solubilization characteristics in the presence of biological fluids.
ZnAl–Zr(X) hydrotalcite-like materials were synthesized by co-precipitation using a Zn/Al molar ratio of 2 and Zr/Al(X) molar ratios of 0.0, 0.10, and 0.25. The effect of the activation temperature on the catalytic performance of these materials was analyzed, revealing that at relatively low temperature (200 °C), the collapse of the material structure is diminished, leading to FAME yields varying from 68 to 82%. This remarkable catalytic activity is related to the formation of hydrotalcite, zincite, and hydrozincite which in turn lead to the generation of Brönsted basic sites and Lewis acid–basic pairs. Incorporation of Zr+4 into the brucite-like structure of hydrotalcites enhances the basicity of ZnAl–Zr(X) catalysts, which correlates well with the increase in catalytic activity observed for these catalysts. The stability of the ZnAl–Zr(0.25) catalyst was further studied, showing insignificant deactivation after five subsequent reaction cycles. A simplified reaction scheme was proposed for the transesterification reaction over these materials.
The aim of this study was twofold: (a) To validate a successful aging model in a Spanish older adult’s sample, and (b) to predict successful aging from psychosocial factors and physical activity. Participants were 725 Spanish older people, of whom 478 were women and 247 men, aged between 55 and 100 years. Of these, 501 were physically active and 197 persons did not practice physical activity. The sample was collected in three areas: Sport centers, day centers and public areas of several Spanish towns. Factorial validity of the Successful Aging Inventory was studied by confirmatory factor analysis, and four multiple regressions to predict each of the dimensions of successful aging (functional performance, intrapsychic factors, gerotranscendence, and spirituality) were estimated. The model of successful aging in Spanish elderly through the Successful Aging Inventory was adequate. The four multiple regressions predicted highly successful aging, with effect sizes of: R2 = .037 for spirituality; .267 for functional performance; .531 for intrapsychic factors; and .356 for gerotrascendece. A main conclusion derived from the results is that older people who do exercise achieve better aging. Another point is that aspects of health and life satisfaction are directly related to better aging while social aspects influence indirectly.
To compare the epidemiology, clinical characteristics, and mortality of patients with bloodstream infections (BSI) caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) versus ESBL-producing Klebsiella pneumoniae (ESBL-KP) and to examine the differences in clinical characteristics and outcome between BSIs caused by isolates with CTX-M versus other ESBL genotypes
As part of the INCREMENT project, 33 tertiary hospitals in 12 countries retrospectively collected data on adult patients diagnosed with ESBL-EC BSI or ESBL-KP BSI between 2004 and 2013. Risk factors for ESBL-EC versus ESBL-KP BSI and for 30-day mortality were examined by bivariate analysis followed by multivariable logistic regression.
The study included 909 patients: 687 with ESBL-EC BSI and 222 with ESBL-KP BSI. ESBL genotype by polymerase chain reaction amplification of 286 isolates was available. ESBL-KP BSI was associated with intensive care unit admission, cardiovascular and neurological comorbidities, length of stay to bacteremia >14 days from admission, and a nonurinary source. Overall, 30-day mortality was significantly higher in patients with ESBL-KP BSI than ESBL-EC BSI (33.7% vs 17.4%; odds ratio, 1.64; P=.016). CTX-M was the most prevalent ESBL subtype identified (218 of 286 polymerase chain reaction-tested isolates, 76%). No differences in clinical characteristics or in mortality between CTX-M and non–CTX-M ESBLs were detected.
Clinical characteristics and risk of mortality differ significantly between ESBL-EC and ESBL-KP BSI. Therefore, all ESBL-producing Enterobacteriaceae should not be considered a homogeneous group. No differences in outcomes between genotypes were detected.
The aim of this research is to ameliorate the dispersion of pristine and functionalized Carbon Nanotubes (CNTs) into polystyrene with hydroxyl end groups (PSOH) matrices using low magnetic fields. The Multi-Walled Carbon Nanotubes (MWCNTs) were synthesized by chemical vapor deposition (CVD) using benzene as carbon source; to produce CNTs with and without functional groups two catalysts were used (stainless steel and ferrocene). The obtained nanotubes contained iron nanoparticles inside. PSOH were synthesized using styrene as monomer, azobisisobutyronitrile as initiator and 2-MeOH as chain transfer agent. The MWCNTs-PSOH matrices were formed using 1.6 wt % of carbon nanotubes into PSOH and ultrasonic mixing for 30 min. The mixing materials were poured into containers and dry at room temperature. While the material was drying, constant magnetic fields of 0.24 T were being applied for 50 min. The MWCNTs-PSOH composites were analysed by SEM, FTIR and Raman spectroscopy. SEM micrographs showed that MWCNTs without functional groups were incorporated in the middle of PSOH. The MWCNTs functionalized perform differently; a better dispersion through the entire polymer matrix was achieved, because the polymer embedded the CNTs. FTIR and Raman spectroscopy showed chemical interaction between PSOH and MWCNTs functionalized. The CNTs dispersion into PSOH was ameliorated through the use of low magnetic fields and functionalization.
Hydroxyapatite [HAp, Ca5(PO4)3(OH)] was synthesized by chemical precipitation, using H3PO4 and Ca(OH)2 as chemical precursors. The precursors were slowly mixed in suitable proportions aiming to obtain Ca/P molar ratios of 1.5, 1.67 or 2.0 in the reacting suspension. This was followed by 21.5 h of aging. Both reaction and aging stages were carried out under an atmosphere of still ambient air and under continuous stirring, either at room temperature, 60 or 90 °C. The precipitates were characterized by ICP-AES and XRD. The results suggested that the most suitable Ca/P molar ratio for the production of pure phase HAp is Ca/P = 1.67, as long as the initial Ca(OH)2 particle size and/or the suspension pH are carefully controlled, especially when the synthesis is carried out above room temperature.
Glasses and glass-ceramics of the system Diopside [D, CaMgSi2O6] - Fluorapatite [FAp, Ca5(PO4)3F] were synthesized and characterized. The studied theoretical phase compositions were (wt%): 1) 70% D-30% FAp, 2) 60% D-40% FAp and 3) 80% D-20% FAp. The glass-ceramics were synthesized by isothermal treatment of the corresponding parent glasses at either 800, 900 or 1000 °C, with holding times of either 30 min, 2 h or 5 h at high temperature. The in vitro bioactivities of all materials were tested in Kokubo’s Simulated Body Fluid (SBF), for 21 days at pH = 7.4 and 37 °C. All materials were characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM/EDS). In all cases, the in vitro bioactivity increased with decreasing crystallization degree in the materials, which was likely due to an inhibitory effect of the structural changes occurring during thermal treatment of the glasses. This was more accentuated for long thermal treatments. After 21 days of soaking in the SBF, an apatite-like surface layer, with a Ca/P molar ratio close to 1.67, was formed in the case of the parent glass of composition 2. This was attributed to an enhancing effect of so-called “phase separation” phenomenon that took place during the synthesis of that particular glass. Lastly, the MgO content of the glasses made no clear difference on their in vitro bioactivity.
Early awareness and alert systems (EAAS) try to anticipate the impact of new technologies in the healthcare systems. Spain, which has a decentralized health system with public provision and universal health coverage, has been a pioneer in establishing EAAS activities. From 2006 a network of regional agencies coordinated EAAS activities. Taking into account the individual agencies scarce resources and in order to improve efficiency, this collaboration decided to distribute tasks when identifying and early assessment of new and emerging health technologies. The aim was to inform the common benefit package of the Spanish public health system.
Four out of eight Spanish Health Technology Assessment (HTA) agencies had EAAS in Spain (AETS-Carlos III Institute; AETSA-Andalusia; Avalia-t-Galicia; Osteba-Basque Country). Each agency has taken care of different sources for the identification of new and emerging non-drug health technologies: industry and innovator contacts, health expert networks, mass media and EAAS databases. Members of the network used the same filtration criteria to reach the final list. The system will run in parallel to a biannual identification process in major databases.
In 2016, the network identified and filtered sixty-three technologies: ten by mass media; five by health experts; thirty-five other EAAS and thirteen by direct contact with industry and innovators. Main represented specialties were: endocrinology (seven); gynecology and obstetrics (six); cardiology and cardiac surgery (five); emergency medicine (four); dermatology (three) and pneumology (three). Technologies were grouped by specialty in order to inform the different commissions that discuss inclusion in the Spanish Benefit Package. Specialty monographs will be published to inform stakeholders.
The approach is feasible, and increases the capacity of individual agencies to address the needs of the national and regional systems by improving their efficiency. There is a need to previously define the methods and the criteria that will be used for the identification and filtration.
Tunisia recently implemented a Health Technology Assessment (HTA) agency (INASanté) to inform decisions around health technologies and to improve clinical practice by means of the elaboration of Clinical Practice Guidelines (CPG). However many decisions on new and emerging technologies, their implementation and coverage in the health care system are still taken at the hospital level without any structured process that informs the decisions. The aim of this project was to improve the methods and flow-chart of decision-making processes on innovation uptake in the Tunisia Healthcare System.
By means of the toolkit of EuroScan for the implementation of an early awareness and alert system (EAAS), and its checklist, it was discussed specifically within INASanté the characteristics of the Tunisia Healthcare System and its specificities regarding decisions on drugs and medical devices. The analysis included the process of innovation uptake at the hospital level and its specific flow-chart. In depth interviews and a devoted workshop were performed with personal in INASanté: two physicians (one involved in CPG elaboration and the second in accreditation), three pharmacists (HTA), one nutritionist (HTA), two librarians and other stakeholders, including the Directorate of Hospitals.
The uptake of innovations in Tunisia does not follow a structured process. In fact, there is no central purchase of medical devices in Tunisia and most medical devices are purchased by hospitals within a tender process in accordance with the Tunisian public procurement law. The main pitfalls are: lack of awareness around innovations that could impact the system, non-structured process of information sharing among the different decision-makers that promotes inequity in access to technologies and services, and lack of explicit criteria that determine decisions around health technologies.
Tunisia requires a structured and informed process on decisions around innovation uptake in the healthcare system. The principles that should govern this system are: anticipation of the impact of new health technologies, establishing priorities and criteria for decision making in all places of decision. The decisions should be recorded and publicly shared to avoid inequities in the access to technologies.
Coronary heart disease (CHD) is the most common cause of mortality globally. The burden of CHD is a challenge for Tunisia causing 27.14 percent of total mortality (1).
Statins are the leading molecules used to prevent CHD in Tunisia. The amount paid by the national insurance fund for statins in 2015 represents 9 percent of total drug expenditures (2).
INASanté has launched a Health Technology Assessment (HTA) study to compare the intensification of statin monotherapy versus a combination therapy for the CHD prevention in patients with moderate to high cardiovascular risk. The aim of this contextualized HTA report is to diminish prescription variability and not justified therapies.
Research was carried out in the following databases: CRD, NICE search evidence, Cochrane, Belgian Health Care Knowledge Centre (KCE), Canadian Agency for Drugs and Technologies in Health (CADTH), Adelaide Health Technology Assessment (AHTA), Institut National d'excellence En Santé et en Services Sociaux (INESS), Euroscan International Network, National Institute for Health Research (NIHR), Agency for Healthcare Research and Quality (AHRQ) and Haute Autorité de Santé (HAS) from 2006 to 2017. Title, abstract and full text screening were performed by two independent reviewers relying on prespecified eligibility criteria. Critical appraisal of literature was conducted using INAHTA and PRISMA checklists, FLC 2.0 and The European Network for HTA (EUnetHTA) adaptation toolkit. One review from AHRQ was retained.
An adaptation process has been launched. Data on lipid lowering agents intake from key institutions have been gathered and a qualitative study has been started through interviews with thirty-three cardiologists and general practitioners from public, private sector and scientifc societies. Interviews have been analysed using NVivo. After results discussion with the working group, the report will be synthesized and validated.
According to the AHRQ report, all evidence for clinical outcomes were graded insufficient when comparing the therapies. Results on lowering low density lipoprotein (LDL-C) depend on the combination agent Ezetimibe has shown remarkable results (3).
The Tunisian context shows that there is no standardized method to assess the cardiovascular risk according to the preliminary results. The only combination therapy reported is with fibrates, mainly in case of associated hypertriglyceridemia. Ezetimibe has not yet obtained the marketing authorization.
There are significant differences between contexts and among practitioners prescriptions. This can be related to the lack of common guidelines and inequitable access to drugs and healthcare resources in general.
The Spanish National Network (REDETS) is a group of eight agencies, units and services, depending on National and Regional Governments that coordinate their work within a common methodological framework, guided by the principles of mutual recognition and cooperation. The necessity of considering a Quality Management System has been detected and, consequently, a common tool for all the members needs to be developed. We describe in this study the process to achieve that goal.
Based on both a review of previous literature and the proposal for a self-evaluating tool, a group of experts from each agency through consensus have developed a tool for self-evaluation in Health Technology Assessment (HTA) agencies. Through the structure described in the handbook of the Andalusian Agency for Healthcare Quality (ACSA), each standard should have a statement or proposal that needs to also include evidence or good practices, and the corresponding evaluation questions. In separate workgroups, the definition of these proposals, evidence and evaluation questions were developed. One face-to-face meeting and two meetings via teleconference were necessary to achieve a final document with all the quality standards.
From a proposed structure of sixty-six standards, the titles, definitions, statements and evidence as well as good practices and evaluation questions were established in workgroups with consensus among all of the members (1 - 3). The final version of the self-assessment tool was composed of sixty-eight standards, grouped in twelve quality criteria structured in four dimensions: I Responsibility, II Clients and Stakeholders, III Production Process, and IV Resources.
Quality management requires an evaluation tool and this version, based on a systematic review and consensus, is a useful and practical instrument for developing a handbook by each member of REDETS. An online version of the tool is in process of development.
Health Technology Assessment (HTA) reports adaptation process is an important tool for emerging HTA agencies. INASanté (National Instance for Accreditation in Healthcare) has chosen to rely on this approach, to develop its first health intervention assessment report: comparative study of computed tomographic colonography versus standard colonoscopy for colorectal cancer screening.
Following consultations with healthcare professionals, the PICO question related to the colorectal cancer screening issue in Tunisia was determined. A literature search strategy covering 10 years (2006-2016) was carried out. Several databases including HTA on the net were explored. Then two independent reviewers conducted literature screening and realized a PRISMA flow diagram. Full text selected reports were submitted to three critical appraisal tools: PRISMA checklist, INAHTA checklist and Critical Appraisal Tools (FLC 2.0). The EUnetHTA adaptation toolkit was used to determine reports adaptability by assessing relevance, reliability and transferability. A structured study of the Tunisian context based on a qualitative data analysis was elaborated. The data synthesis and reporting were finalized with the contribution of a working group. Then an external peer review was conducted before the report dissemination.
Eighty reports were screened to finally retain four eligible. After a critical appraisal performed by two independent reviewers, two reports from the Canadian Agency for Drug and Technolgies in Healthcare and AETSA were selected to be assessed using the EUnetHTA adaptation toolkit. Regarding transferability criteria, the second report was retained. The context study has consisted in a qualitative analysis of seventeen individual interviews with healthcare professionals involved in colorectal cancer screening issues and an up to date Tunisian literature review. The final adapted report was a combination between relevant extracted data from AETSA report and synthesis of the Tunisian context analysis.
This HTA report represents a tool for policy makers to establish the appropriate colorectal cancer screening program for the Tunisian context. HTA reports adaptation process is the best way to give evidence on emerging technologies without wasting time and resources.
Objectives: To test the hypothesis that brain arterial diameters are associated with cognitive performance, particularly in arteries supplying domain-specific territories. Methods: Stroke-free participants in the Northern Manhattan Study were invited to have a brain MRI from 2003–2008. The luminal diameters of 13 intracranial arterial segments were obtained using time-of-flight magnetic resonance angiogram (MRA), and then averaged and normalized into a global score and region-specific arterial diameters. Z-Scores for executive function, semantic memory, episodic memory and processing speed were obtained at MRI and during follow-up. Adjusted generalized additive models were used to assess for associations. Results: Among the 1034 participants with neurocognitive testing and brain MRI, there were non-linear relationships between left anterior (ACA) and middle cerebral artery (MCA) diameter and semantic memory Z-scores (χ2=10.00; DF=3; p=.019), and left posterior cerebral artery (PCA) and posterior communicating artery (Pcomm) mean diameter and episodic memory Z-scores (χ2=9.88; DF=3; p=.020). Among the 745 participants who returned for 2nd neuropsychological testing, on average 5.0±0.4 years after their MRI, semantic memory change was associated non-linearly with the left PCA/Pcomm mean diameter (χ2=13.09; DF=3; p=.004) and with the right MCA/ACA mean diameter (χ2=8.43; DF=3; p=.03). In both cross-sectional and longitudinal analyses, participants with the larger brain arterial diameters had more consistently lower Z-scores and greater decline than the rest of the participants. Conclusions: Brain arterial diameters may have downstream effects in brain function presenting as poorer cognition. Identifying the mechanisms and the directionality of such interactions may increase the understanding of the vascular contribution to cognitive impairment and dementia. (JINS, 2018, 24, 335–346)