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41.
42.
Nina G. G. Domingo Srinidhi Balasubramanian Sumil K. Thakrar Michael A. Clark Peter J. Adams Julian D. Marshall Nicholas Z. Muller Spyros N. Pandis Stephen Polasky Allen L. Robinson Christopher W. Tessum David Tilman Peter Tschofen Jason D. Hill 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(20)
Agriculture is a major contributor to air pollution, the largest environmental risk factor for mortality in the United States and worldwide. It is largely unknown, however, how individual foods or entire diets affect human health via poor air quality. We show how food production negatively impacts human health by increasing atmospheric fine particulate matter (PM2.5), and we identify ways to reduce these negative impacts of agriculture. We quantify the air quality–related health damages attributable to 95 agricultural commodities and 67 final food products, which encompass >99% of agricultural production in the United States. Agricultural production in the United States results in 17,900 annual air quality–related deaths, 15,900 of which are from food production. Of those, 80% are attributable to animal-based foods, both directly from animal production and indirectly from growing animal feed. On-farm interventions can reduce PM2.5-related mortality by 50%, including improved livestock waste management and fertilizer application practices that reduce emissions of ammonia, a secondary PM2.5 precursor, and improved crop and animal production practices that reduce primary PM2.5 emissions from tillage, field burning, livestock dust, and machinery. Dietary shifts toward more plant-based foods that maintain protein intake and other nutritional needs could reduce agricultural air quality–related mortality by 68 to 83%. In sum, improved livestock and fertilization practices, and dietary shifts could greatly decrease the health impacts of agriculture caused by its contribution to reduced air quality.The health and environmental consequences of feeding the increasingly large and affluent global population are becoming increasingly apparent. These consequences have spurred interest in identifying food production practices and diets that improve human health and reduce environmental harm. Recent work has demonstrated that many of the opportunities for food producers and consumers to improve nutritional outcomes also have environmental benefits, such as reducing greenhouse gas emissions, land and water use, and eutrophication (1–6). It is largely unknown, however, how individual foods and diets affect air quality, even though air pollution is the largest environmental mortality risk factor in the United States and globally (7, 8), and agriculture is itself known to be a major contributor to reduced air quality (8, 9). In the United States alone, atmospheric fine particulate matter (PM2.5) from anthropogenic sources is responsible for about 100,000 premature deaths each year, one-fifth of which are linked to agriculture (10, 11).Here, we show how different foods affect human health by reducing air quality. We consider the emission of pollutants that contribute to atmospheric PM2.5, the chronic exposure to which increases the incidence of premature mortality from cardiovascular disease, cancer, and stroke (12, 13). These pollutants include directly emitted PM2.5 (primary PM2.5) and PM2.5 formed in the atmosphere (secondary PM2.5) from the precursors ammonia (NH3), nitrogen oxides (NOx), sulfur dioxide (SO2), and nonmethane volatile organic compounds (NMVOCs). From a spatially explicit inventory of emissions of primary PM2.5 and secondary PM2.5 precursors from agricultural supply chain activities for commodities in the contiguous United States (SI Appendix, Figs. S1 and S2) (14, 15) (Materials and Methods), we estimate increases in atmospheric concentrations of total (primary + secondary) PM2.5 attributable to agricultural emissions; total PM2.5 transport, chemistry, and removal; and exposure of populations to total PM2.5 using an ensemble of three independent air quality models (16–19). We describe damages attributable to 95 agricultural commodities and 67 final food products (full list in SI Appendix, Table S1), which cover >99% of US agricultural production (20). 相似文献
43.
Srinivas BK Gopalakrishnan M Mahadevan R Satyaprasad V 《Asian cardiovascular & thoracic annals》2002,10(1):64-65
A 36-year-old female was admitted with dyspnea on exertion of one year's duration. Echocardiography revealed a tumor arising from interventricular septum with dynamic left ventricular outflow tract obstruction. On cardiopulmonary bypass with cardioplegic arrest, the tumor was approached through a transverse aortotomy, and excised from the interventricular septum through the aortic valve. Postoperative recovery was uneventful and the patient was asymptomatic with no recurrence at follow-up after one year. 相似文献
44.
Dhingra R Pencina MJ Benjamin EJ Levy D Larson MG Meigs JB Rifai N D'Agostino RB Vasan RS 《American journal of hypertension》2004,17(10):891-896
BACKGROUND: Increased sodium intake has been positively associated with high blood pressure (BP) and hypertensive target organ damage, but associations with cardiac structure in nonhypertensive individuals have yielded inconsistent results. We tested the hypothesis that sodium intake is associated with left ventricular (LV) mass and left ventricular hypertrophy (LVH), independent of BP, in the community. METHODS: We analyzed the cross-sectional relationships between urinary sodium excretion and LV measurements in a community-based sample of 2660 Framingham Offspring Study participants (mean age 58 years, 56% women and 44% men). Participants with known coronary artery disease, congestive heart failure, or renal failure as well as those using diuretics were excluded. Urinary sodium excretion was measured on a spot urine sample and was indexed to urinary creatinine. RESULTS: In sex-specific, multivariable linear regression models adjusting for covariates known to influence LV measurements, log urinary sodium was not associated with LV mass, wall thickness, end-diastolic dimensions, or left atrial size in either sex. Urinary sodium was not related to LVH defined as LV mass >/= sex-specific 80th percentile value. In analyses restricted to hypertensive individuals (n = 983, 470 women), urinary sodium was not associated with LV mass or LVH. CONCLUSIONS: In our large community-based sample, urinary sodium excretion was not related to LV mass, function, or hypertrophy. 相似文献
45.
Alcohol is a known hepatotoxic agent, which may exacerbate liver injury caused by other agents. The wide prevalence of alcohol use and abuse in society makes it an important cofactor in many other liver diseases. Examples of liver diseases that are significantly influenced by ingestion of alcohol include chronic viral hepatitis, disorders of iron overload, and obesity-related liver disease. 相似文献
46.
Srikanth Vedachalam Gokulakrishnan Balasubramanian Garrie J Haas Somashekar G Krishna 《World journal of gastroenterology : WJG》2020,26(20):2550-2558
Left ventricular assist devices(LVAD) are increasingly become common as life prolonging therapy in patients with advanced heart failure. Current devices are now used as definitive treatment in some patients given the improved durability of continuous flow pumps. Unfortunately, continuous flow LVADs are fraught with complications such as gastrointestinal(GI) bleeding that are primarily attributed to the formation of arteriovenous malformations. With frequent GI bleeding, antiplatelet and anticoagulation therapies are usually discontinued increasing the risk of life-threatening events. Small bowel bleeds account for 15%as the source and patients often undergo multiple endoscopic procedures.Treatment strategies include resuscitative measures and endoscopic therapies.Medical treatment is with octreotide. Novel treatment options include thalidomide, angiotensin converting enzyme inhibitors/angiotensin Ⅱ receptor blockers, estrogen-based hormonal therapies, doxycycline, desmopressin and bevacizumab. Current research has explored the mechanism of frequent GI bleeds in this population, including destruction of von Willebrand factor,upregulation of tissue factor, vascular endothelial growth factor, tumor necrosis factor-α, tumor growth factor-β, and angiopoetin-2, and downregulation of angiopoetin-1. In addition, healthcare resource utilization is only increasing in this patient population with higher admissions, readmissions, blood product utilization, and endoscopy. While some of the novel endoscopic and medical therapies for LVAD bleeds are still in their development stages, these tools will yet be crucial as the number of LVAD placements will likely only increase in the coming years. 相似文献
47.
48.
Jeffrey D. Hirsch Eliot L. Siegel Sridhar Balasubramanian Kenneth C. Wang 《Journal of digital imaging》2015,28(4):407-411
The Digital Imaging and Communications in Medicine (DICOM) standard is the universal format for interoperability in medical imaging. In addition to imaging data, DICOM has evolved to support a wide range of imaging metadata including contrast administration data that is readily available from many modern contrast injectors. Contrast agent, route of administration, start and stop time, volume, flow rate, and duration can be recorded using DICOM attributes [1]. While this information is sparsely and inconsistently recorded in routine clinical practice, it could potentially be of significant diagnostic value. This work will describe parameters recorded by automatic contrast injectors, summarize the DICOM mechanisms available for tracking contrast injection data, and discuss the role of such data in clinical radiology. 相似文献
49.
Is visfatin an adipokine or myokine? Evidence for greater visfatin expression in skeletal muscle than visceral fat in chickens 总被引:9,自引:0,他引:9
Krzysik-Walker SM Ocón-Grove OM Maddineni SR Hendricks GL Ramachandran R 《Endocrinology》2008,149(4):1543-1550
Visfatin, an adipokine hormone produced primarily by visceral adipose tissue in mammals, has been implicated in the immune system, cellular aging, and glucose metabolism. Increased visceral adiposity and hyperglycemia have been correlated with elevated plasma visfatin levels in humans. The present study investigated visfatin cDNA and protein expression as well as plasma visfatin levels in chickens that are selected for rapid growth and are naturally hyperglycemic relative to mammals. By RT-PCR, we detected visfatin cDNA in multiple tissues in the chicken. The deduced amino acid sequence of full-length chicken visfatin was 92-93% homologous to mammalian visfatin. Using real-time quantitative PCR and Western blotting, chicken skeletal muscle was found to contain 5- and 3-fold greater quantities of visfatin mRNA and protein than abdominal fat pad, respectively. Visfatin mRNA and protein quantities were not significantly different among sc and visceral adipose tissue depots. Skeletal muscle visfatin mRNA and protein quantities as well as plasma visfatin levels determined by enzyme immunoassay were significantly higher in 8-wk-old compared with 4-wk-old chickens, possibly due to rapid skeletal muscle growth and visceral fat accretion occurring in broiler chickens during this period. However, fasting and refeeding did not affect plasma visfatin levels in the chicken. Collectively, our results provide novel evidence that skeletal muscle, not the visceral adipose tissue, is the primary source of visfatin in chickens, thereby raising the possibility that visfatin may be acting as a myokine affecting skeletal muscle growth and metabolism. 相似文献
50.
G B Gordon S P Spielberg D A Blake V Balasubramanian 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(4):2545-2548
It was postulated that thalidomide causes birth defects by being metabolized to a toxic electrophilic intermediate. This hypothesis was tested by using an in vitro assay in which drug toxicity to human lymphocytes was assessed in the presence of a hepatic microsomal drug metabolizing system. Maternal hepatic microsomes from pregnant rabbits mediated the production of a metabolite that was toxic to lymphocytes. Toxicity was enhanced by inhibitors of epoxide hydrolase (EC 3.3.2.3) and abolished by adding the purified enzyme to the incubation medium. The metabolite thus appears to be in arene oxide, consistent with the previously reported isolation of phenolic metabolites of thalidomide from the urine of treated animals. Two teratogenic analogs of thalidomide (phthalimidophthalimide and phthalimidinoglutarimide) were also toxic in the system; two nonteratogenic analogs (phthalimide and hexahydrothalidomide) were not toxic, even in the presence of epoxide hydrolase inhibitors. The toxic metabolite of thalidomide was not produced by rat liver microsomes (the rat is not sensitive to thalidomide teratogenesis) but was produced by hepatic preparations from maternal rabbits, and rabbit, monkey, and human (all sensitive species) fetuses. A toxic arene oxide therefore may be involved in the teratogenicity of thalidomide. 相似文献