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1.
BMJ ; 367: l6258, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776122

RESUMO

OBJECTIVE: To assess risks and costs of hospital admission associated with short term exposure to fine particulate matter with diameter less than 2.5 µm (PM2.5) for 214 mutually exclusive disease groups. DESIGN: Time stratified, case crossover analyses with conditional logistic regressions adjusted for non-linear confounding effects of meteorological variables. SETTING: Medicare inpatient hospital claims in the United States, 2000-12 (n=95 277 169). PARTICIPANTS: All Medicare fee-for-service beneficiaries aged 65 or older admitted to hospital. MAIN OUTCOME MEASURES: Risk of hospital admission, number of admissions, days in hospital, inpatient and post-acute care costs, and value of statistical life (that is, the economic value used to measure the cost of avoiding a death) due to the lives lost at discharge for 214 disease groups. RESULTS: Positive associations between short term exposure to PM2.5 and risk of hospital admission were found for several prevalent but rarely studied diseases, such as septicemia, fluid and electrolyte disorders, and acute and unspecified renal failure. Positive associations were also found between risk of hospital admission and cardiovascular and respiratory diseases, Parkinson's disease, diabetes, phlebitis, thrombophlebitis, and thromboembolism, confirming previously published results. These associations remained consistent when restricted to days with a daily PM2.5 concentration below the WHO air quality guideline for the 24 hour average exposure to PM2.5. For the rarely studied diseases, each 1 µg/m3 increase in short term PM2.5 was associated with an annual increase of 2050 hospital admissions (95% confidence interval 1914 to 2187 admissions), 12 216 days in hospital (11 358 to 13 075), US$31m (£24m, €28m; $29m to $34m) in inpatient and post-acute care costs, and $2.5bn ($2.0bn to $2.9bn) in value of statistical life. For diseases with a previously known association, each 1 µg/m3 increase in short term exposure to PM2.5 was associated with an annual increase of 3642 hospital admissions (3434 to 3851), 20 098 days in hospital (18 950 to 21 247), $69m ($65m to $73m) in inpatient and post-acute care costs, and $4.1bn ($3.5bn to $4.7bn) in value of statistical life. CONCLUSIONS: New causes and previously identified causes of hospital admission associated with short term exposure to PM2.5 were found. These associations remained even at a daily PM2.5 concentration below the WHO 24 hour guideline. Substantial economic costs were linked to a small increase in short term PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Hospitalização/estatística & dados numéricos , Material Particulado/análise , Idoso , Poluentes Atmosféricos/economia , Poluição do Ar/economia , Custos e Análise de Custo , Estudos Cross-Over , Exposição Ambiental/economia , Feminino , Hospitalização/economia , Humanos , Masculino , Medicare , Pessoa de Meia-Idade , Material Particulado/economia , Fatores de Risco , Fatores de Tempo , Estados Unidos
2.
Mol Nutr Food Res ; 63(24): e1900612, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31703241

RESUMO

SCOPE: Vegetarian diets confer health benefits to many cardiometabolic diseases, although whether and how gut microbiota in vegetarians contributes to host metabolism remains unclear. Thus, the aim is to explore the possible links between the gut microbiota and circulating gut microbiota-host co-metabolites among vegetarians and omnivores. METHODS AND RESULTS: Fecal and serum samples from 36 adults following a vegan, lacto-ovo vegetarian, or omnivorous diet are collected. A 16S rRNA gene, metagenome, metatranscriptome, and metabolome integrated multi-omics approach is adopted to profile fecal microbial composition and functionality and circulating gut microbiota-host co-metabolites. 16S rRNA gene and metagenomic sequencing suggest a significant difference in gut microbial composition between the two vegetarian groups and the omnivorous group at the family, genus, and species level. Metabolomic analysis reveals that circulating branched-chain amino acids (BCAAs)-valine, leucine, and isoleucine-are significantly lower in the two vegetarian groups than those in the omnivorous group. In line with the lower concentrations of BCAAs, metatranscriptomic analysis shows that the gut microbial pathway for the degradation of BCAAs is significantly upregulated among vegetarians compared with the omnivores. CONCLUSIONS: The results indicate that gut microbiota plays an important role in the modulation of circulating BCAAs among vegetarians.

3.
Free Radic Biol Med ; 141: 393-407, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31279968

RESUMO

Exposure to fine particular matter (≤2.5 µM, PM2.5) contributes to increased risk of obesity and type 2 diabetes. Hydroxytyrosol (HT), a simple polyphenol found in virgin olive oil, is considered to be beneficial for cardiovascular and metabolic disorders. The current study determined whether HT could improve PM2.5-induced adiposity and insulin resistance (IR), and explored the underlying mechanisms. Fifteen adult female C57BL/6j mice on a chow diet were randomly divided into three groups receiving (1) sterile PBS, (2) PM2.5 suspended in sterile PBS (1 mg/mL) and (3) PM2.5+HT (50 mg/kg/day). PM2.5/PBS exposure was administered by oropharynx instillation every other day and HT supplementation was achieved by gavage every day. Four-week PM2.5 exposure did not affect body weight, but significantly increased visceral fat mass. The abdominal adiposity coincided with adipocyte hypertrophy and proliferation in visceral white adipose tissue (WAT), as well as decreased metabolic activity in brown adipose tissue and subcutaneous WAT. PM2.5 enhanced the oxidative stress by diminishing antioxidant enzyme activities in liver and serum, whereas contents of 4-hydroxynonenal (4-HNE), malondialdehyde (MDA) levels in liver and serum were elevated. These changes were accompanied by macrophage infiltration and activation of NF-κB pathway in the liver. Moreover, PM2.5 exposure led to glucose intolerance and insulin insensitivity, impaired hepatic glycogenesis, and decreased insulin-stimulated Akt phosphorylation in peripheral tissues. Importantly, HT treatment prevented PM2.5-induced visceral adipogenesis, oxidative stress, hepatic inflammation and NF-κB activation, systemic and peripheral IR. In vitro, after HepG2 cells were incubated with PM2.5 (0, 5, 25, 50, 100 and 200 µg/mL), reduced glutathione depletion and 4-HNE, 8-hydroxy-2'-deoxyguanosine, MDA increment in a dose-dependent manner were observed; likewise, insulin-stimulated glucose uptake decreased in a dose-dependent manner. Further, with antioxidant NAC and NF-κB inhibitor PDTC, we confirmed that HT attenuated PM2.5-induced IR through restraining NF-κB activation evoked by oxidative stress. In addition, HT could expand gut microbiota richness, reduce pathogenic bacteria and accommodate the microbial architecture in PM2.5-exposed mice, which were correlated with parameters of adiposity, oxidative stress and glycometabolism. HT could effectively correct imbalanced oxidative stress triggered by PM2.5, in turn ameliorated NF-κB pathway and insulin signaling. Gut microbiota may mediate the actions of HT.

4.
Environ Int ; 126: 228-233, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30822651

RESUMO

Human-induced climate change has accelerated in recent decades, causing adverse health effects. However, the impact of the changing climate on neurological disorders in the older population is not well understood. We applied time-varying Cox proportional hazards models to estimate the associations between hospital admissions for dementia and the mean and variability of summer and winter temperatures in New England. We estimated seasonal temperatures for each New England zip code using a satellite-based prediction model. By characterizing spatial differences and temporal fluctuations in seasonal temperatures, we observed a lower risk of dementia-associated hospital admissions in years when local temperatures in either summer (hazard ration [HR] = 0.98; 95% confidence interval [CI]: 0.96, 1.00) or winter (HR = 0.97; 95% CI: 0.94, 0.99) were higher than average, and a greater risk of dementia-associated admissions for older adults living in zip codes with higher temperature variations. Effect modifications by sex, race, age, and dual eligibility were considered to examine vulnerability of population subgroups. Our results suggest that cooler-than-average temperatures and higher temperature variability increase the risk of dementia-associated hospital admissions. Thus, climate change may affect progression of dementia and associated hospitalization costs.


Assuntos
Mudança Climática , Demência/epidemiologia , Hospitalização/estatística & dados numéricos , Temperatura Ambiente , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , New England/epidemiologia , Estações do Ano
5.
Environ Health ; 18(1): 9, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30691464

RESUMO

BACKGROUND: Exposure to ambient particulate matter generated from coal-fired power plants induces long-term health consequences. However, epidemiologic studies have not yet focused on attributing these health burdens specifically to energy consumption, impeding targeted intervention policies. We hypothesize that the generating capacity of coal-fired power plants may be associated with lung cancer incidence at the national level. METHODS: Age- and sex-adjusted lung cancer incidence from every country with electrical plants using coal as primary energy supply were followed from 2000 to 2016. We applied a Poisson regression longitudinal model, fitted using generalized estimating equations, to estimate the association between lung cancer incidence and per capita coal capacity, adjusting for various behavioral and demographic determinants and lag periods. RESULTS: The average coal capacity increased by 1.43 times from 16.01 gigawatts (GW) (2000~2004) to 22.82 GW (2010~2016). With 1 kW (KW) increase of coal capacity per person in a country, the relative risk of lung cancer increases by a factor of 59% (95% CI = 7.0%~ 135%) among males and 85% (95% CI = 22%~ 182%) among females. Based on the model, we estimate a total of 1.37 (range = 1.34 ~ 1.40) million standardized incident cases from lung cancer will be associated with coal-fired power plants in 2025. CONCLUSIONS: These analyses suggest an association between lung cancer incidence and increased reliance on coal for energy generation. Such data may be helpful in addressing a key policy question about the externality costs and estimates of the global disease burden from preventable lung cancer attributable to coal-fired power plants at the national level.


Assuntos
Carvão Mineral , Neoplasias Pulmonares/epidemiologia , Centrais Elétricas , Feminino , Saúde Global , Humanos , Incidência , Masculino , Risco
6.
Environ Pollut ; : 113476, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31902537

RESUMO

Exposure to chemicals produced by petrochemical industrial complexes (PICs), such as benzene, ionizing radiation, and particulate matters, may contribute to the development of leukemia. However, epidemiological studies showed controversial results. This systematic review and meta-analysis aimed to summarize the association between residential exposure to PICs and the risk of leukemia incidence, focusing on exposure-response effects. We searched PubMed, Embase, Web of Science, and Cochrane Library databases for studies published before September 1st, 2019. Observational studies investigating residential exposure to PICs and the risk of leukemia were included. The outcome of interest was the incidence of leukemia comparing to reference groups. Relative risk (RR) was used as the summary effect measure, synthesized by characteristics of populations, distance to PICs, and calendar time in meta-regression. We identified 7 observational studies, including 2322 leukemia cases and substantial reference groups, in this meta-analysis. Residential exposure to PICs within a maximal 8-km distance had a 36% increased risk of leukemia (pooled RR = 1.36, 95% CI = 1.14-1.62) compared to controls, regardless of sex and age. In terms of leukemia subtypes, residential exposure to PICs was associated with the risks of acute myeloid leukemia (AML, pooled RR = 1.61, 95% CI = 1.12-2.31) and chronic lymphocytic leukemia (CLL, pooled RR = 1.85, 95% CI = 1.11-6.42). In meta-regression, the positive association occurred after 10 years of follow-up with a pooled RRs of 1.21 (95% CI = 1.02-1.44) and then slightly increased to 1.77 (95% CI = 1.35-2.33) at 30 years after follow-up. No effect modification was found by sex, age, and geographic locations.

7.
Environ Res ; 182: 109095, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927244

RESUMO

BACKGROUND: Although many studies have established significant associations between short-term air pollution and the risk of getting cardiovascular diseases, there is a lack of evidence based on causal distributed lag modeling. METHODS: Inverse probability weighting (ipw) propensity score models along with conditional logistic outcome regression models based on a case-crossover study design were applied to get the causal unconstrained distributed (lag0-lag5) as well as cumulative lag effect of short-term exposure to PM2.5/Ozone on hospital admissions of acute myocardial infarction (AMI), congestive heart failure (CHF) and ischemic stroke (IS) among New England Medicare participants during 2000-2012. Effect modification by gender, race, secondary diagnosis of Chronic Obstructive Pulmonary Diseases (COPD) and Diabetes (DM) was explored. RESULTS: Each 10 µg/m3 increase in lag0-lag5 cumulative PM2.5 exposure was associated with an increase of 4.3% (95% confidence interval: 2.2%, 6.4%, percentage change) in AMI hospital admission rate, an increase of 3.9% (2.4%, 5.5%) in CHF rate and an increase of 2.6% (0.4%, 4.7%) in IS rate. A weakened lagging effect of PM2.5 from lag0 to lag5 could be observed. No cumulative short-term effect of ozone on CVD was found. People with secondary diagnosis of COPD, diabetes, female gender and black race are sensitive population. CONCLUSIONS: Based on our causal distributed lag modeling, we found that short-term exposure to an increased ambient PM2.5 level had the potential to induce higher risk of CVD hospitalization in a causal way. More attention should be paid to population of COPD, diabetes, female gender and black race.

8.
Methods Mol Biol ; 726: 111-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21424446

RESUMO

SnO(2) nanowires are synthesized via the chemical-vapor-deposition process using gold as the catalyst and characterized by X-ray powder diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and cathodoluminescence. Finally, a new type of microelectrode based on a single SnO(2) nanowire is fabricated. This microelectrode is expected to have promising applications in various chemical and biomedical nanosensors.


Assuntos
Nanofios/química , Compostos de Estanho/química , Microeletrodos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Nanofios/ultraestrutura , Difração de Raios X
9.
Nano Lett ; 10(9): 3414-9, 2010 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-20681617

RESUMO

This article presents an effective approach for patterned growth of vertically aligned ZnO nanowire (NW) arrays with high throughput and low cost at wafer scale without using cleanroom technology. Periodic hole patterns are generated using laser interference lithography on substrates coated with the photoresist SU-8. ZnO NWs are selectively grown through the holes via a low-temperature hydrothermal method without using a catalyst and with a superior control over orientation, location/density, and as-synthesized morphology. The development of textured ZnO seed layers for replacing single crystalline GaN and ZnO substrates extends the large-scale fabrication of vertically aligned ZnO NW arrays on substrates of other materials, such as polymers, Si, and glass. This combined approach demonstrates a novel method of manufacturing large-scale patterned one-dimensional nanostructures on various substrates for applications in energy harvesting, sensing, optoelectronics, and electronic devices.

11.
Nano Lett ; 10(6): 2092-6, 2010 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-20491431

RESUMO

We present a new approach to fabricate three-dimensional (3D) dye-sensitized solar cells (DSSCs) by integrating planar optical waveguide and nanowires (NWs). The ZnO NWs are grown normally to the quartz slide. The 3D cell is constructed by alternatively stacking a slide and a planar electrode. The slide serves as a planar waveguide for light propagation. The 3D structure effectively increases the light absorbing surface area due to internal multiple reflections without increasing electron path length to the collecting electrode, resulting in a significant improvement in energy conversion efficiency by a factor of 5.8 on average compared to the planar illumination case. Our approach demonstrates a new methodology for building large scale and high-efficient 3D solar cells that can be expanded to organic- and inorganic-based solar cells.

12.
Nat Nanotechnol ; 5(5): 366-73, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20348913

RESUMO

The harvesting of mechanical energy from ambient sources could power electrical devices without the need for batteries. However, although the efficiency and durability of harvesting materials such as piezoelectric nanowires have steadily improved, the voltage and power produced by a single nanowire are insufficient for real devices. The integration of large numbers of nanowire energy harvesters into a single power source is therefore necessary, requiring alignment of the nanowires as well as synchronization of their charging and discharging processes. Here, we demonstrate the vertical and lateral integration of ZnO nanowires into arrays that are capable of producing sufficient power to operate real devices. A lateral integration of 700 rows of ZnO nanowires produces a peak voltage of 1.26 V at a low strain of 0.19%, which is potentially sufficient to recharge an AA battery. In a separate device, a vertical integration of three layers of ZnO nanowire arrays produces a peak power density of 2.7 mW cm(-3). We use the vertically integrated nanogenerator to power a nanowire pH sensor and a nanowire UV sensor, thus demonstrating a self-powered system composed entirely of nanowires.

14.
J Am Chem Soc ; 131(19): 6670-1, 2009 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-19402637

RESUMO

We report an approach to fabricating patterned horizontal ZnO nanowire arrays with a high degree of control over their dimensionality, orientation, and uniformity. Our method combines electron beam lithography and a low temperature hydrothermal decomposition. This approach opens up possibilities to fabricate ZnO NW array based strain and force sensors, two-dimensional photonic crystals, integrated circuit interconnects, and alternative current nanogenerators.


Assuntos
Nanotecnologia/métodos , Nanofios/química , Impressão/métodos , Óxido de Zinco/química , Cristalização , Elétrons
15.
Nano Lett ; 8(11): 4027-32, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18939811

RESUMO

We present a new approach to a nanogenerator (NG) that is composed of integrated, paired nanobrushes made of pyramid-shaped metal-coated ZnO nanotip (NTP) arrays and hexagonal-prism-shaped ZnO nanowire (NW) arrays, which were synthesized using a chemical approach at <100 degrees C on the two surfaces of a common substrate, respectively. The operation of the NGs relies on mechanical deflection/bending of the NWs, in which resonance of NWs is not required to activate the NG. This largely expands the application of the NGs from low frequency (approximately the hertz range) to a relatively high frequency (approximately the megahertz range) for effectively harvesting mechanical energies in our living environment. With one piece of such a structure stacked in close proximity over another to form a layer-by-layer matched brush architecture, direct current is generated by exciting the architecture using ultrasonic waves. A four-layer integrated NG is demonstrated to generate an output power density of 0.11 microW/cm(2) at 62 mV. The layer-by-layer assembly provides a feasible technology for building three-dimensional NGs for applications where force or pressure variations are available, such as a shoe pad, an underskin layer for airplanes, and next to a vibration source such as a car engine or tire.


Assuntos
Nanofios/ultraestrutura , Microscopia Eletrônica de Varredura
16.
J Am Chem Soc ; 130(45): 14958-9, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18921981

RESUMO

We report an approach for growing aligned ZnO nanowire arrays with a high degree control over size, orientation, dimensionality, uniformity, and possibly shape. Our method combines e-beam lithography and a low temperature hydrothermal method to achieve patterned and aligned growth of ZnO NWs at <100degreesC on general inorganic substrates, such as Si and GaN, without using catalyst. This approach opens up the possibility of applying ZnO nanowires as sensor arrays, piezoelectric antenna arrays, two-dimensional photonic crystals, IC interconnects, and nanogenerators.


Assuntos
Gálio/química , Nanofios/química , Silício/química , Óxido de Zinco/química , Catálise , Temperatura Baixa , Cristalização , Polimetil Metacrilato/química , Difração de Raios X
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