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81.
Marshall Burke Anne Driscoll Sam Heft-Neal Jiani Xue Jennifer Burney Michael Wara 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(2)
Recent dramatic and deadly increases in global wildfire activity have increased attention on the causes of wildfires, their consequences, and how risk from wildfire might be mitigated. Here we bring together data on the changing risk and societal burden of wildfire in the United States. We estimate that nearly 50 million homes are currently in the wildland–urban interface in the United States, a number increasing by 1 million houses every 3 y. To illustrate how changes in wildfire activity might affect air pollution and related health outcomes, and how these linkages might guide future science and policy, we develop a statistical model that relates satellite-based fire and smoke data to information from pollution monitoring stations. Using the model, we estimate that wildfires have accounted for up to 25% of PM2.5 (particulate matter with diameter <2.5 μm) in recent years across the United States, and up to half in some Western regions, with spatial patterns in ambient smoke exposure that do not follow traditional socioeconomic pollution exposure gradients. We combine the model with stylized scenarios to show that fuel management interventions could have large health benefits and that future health impacts from climate-change–induced wildfire smoke could approach projected overall increases in temperature-related mortality from climate change—but that both estimates remain uncertain. We use model results to highlight important areas for future research and to draw lessons for policy. 相似文献
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Adedayo Tunde Ajidahun Hellen Myezwa Sam Chidi Ibeneme Sebastian Magobotha Gerhard Fortwengel Maxwell Jingo Brenda Milner Sadiya Ravat Ifeoma Okoye Edward Schnaid Faith Bischoff 《Medicine》2020,99(50)
Introduction:Human Immunodeficiency Virus (HIV) infection remains prevalent co-morbidity, and among fracture patients. Few studies have investigated the role of exercise interventions in preventing bone demineralization in people who have fractures and HIV. If exercise exposed, HIV-infected individuals may experience improved bone health outcomes (BMD), function, quality of life (QoL). The study will aim to assess the impact of home based exercises on bone mineral density, functional capacity, QoL, and some serological markers of health in HIV infection among Nigerians and South Africans.Methods and design:The study is an assessor-blinded randomized controlled trial. Patients managed with internal and external fixation for femoral shaft fracture at the study sites will be recruited to participate in the study. The participants will be recruited 2 weeks post-discharge at the follow-up clinic with the orthopaedic surgeon. The study population will consist of all persons with femoral fracture and HIV-positive and negative (HIV-positive medically confirmed) aged 18 to 60 years attending the above-named health facilities. For the HIV-positive participants, a documented positive HIV result, as well as a history of being followed-up at the HIV treatment and care center. A developed home based exercise programme will be implemented in the experimental group while the control group continues with the usual rehabilitation programme. The primary outcome measures will be function, gait, bone mineral density, physical activity, and QoL.Discussion:The proposed trial will compare the effect of a home-based physical exercise-training programme in the management of femoral fracture to the usual physiotherapy management programmes with specific outcomes of bone mineral density, function, and inflammatory markers.Trial registration:The study was prospectively registered with the Pan African Clinical Trials Registry (Reference number – PACTR201910562118957) on October 21, 2019. (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9425). 相似文献
85.
Central memory self/tumor-reactive CD8+ T cells confer superior antitumor immunity compared with effector memory T cells 总被引:8,自引:0,他引:8 下载免费PDF全文
Klebanoff CA Gattinoni L Torabi-Parizi P Kerstann K Cardones AR Finkelstein SE Palmer DC Antony PA Hwang ST Rosenberg SA Waldmann TA Restifo NP 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(27):9571-9576
Central memory CD8+ T cells (T(CM)) and effector memory CD8+ T cells (T(EM)) are found in humans and mice; however, their relative contributions to host immunity have only recently been examined in vivo. Further, the ability of T(CM) to treat an established tumor or infection has yet to be evaluated. To address the therapeutic potential of different tumor-reactive CD8+ T cell memory subsets, we used an established model for the in vitro generation of T(CM) and T(EM) by using IL-15 and IL-2, respectively. Adoptively transferred T(CM) exhibited a potent in vivo recall response when combined with tumor-antigen vaccination and exogenous IL-2, leading to the eradication of large established tumors. By contrast, T(EM) were far less effective on a per-cell basis. Microarray analysis revealed that the signature of highly in vivo effective antitumor T cells included the overexpression of genes responsible for trafficking to secondary lymphoid tissues. This gene expression profile correctly predicted the in vitro and in vivo lymphoid-homing attributes of tumor-reactive T cells. Furthermore, we found that homing to secondary lymphoid tissue is required for optimal tumor treatment. Our findings indicated that highly in vivo effective antitumor T cells were those that initially targeted secondary lymphoid tissue, rather than tumor sites, as had previously been postulated. Thus, tumor-reactive CD8+ T cell populations with the phenotypic and functional attributes of T(CM) may be superior to T(EM)/effector T cells for adoptive immunotherapies using concomitant tumor-antigen vaccination. 相似文献
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All children with a critical heart disease in a 6.3 million inhabitants territory were referred and all infants who died were autopsied and the protocols sent to the only Center of Pediatric Cardiology and Cardiovascular Surgery. In the first 5 years of the centralized care, 1,122 infants, i.e. 2.36/1,000 live births suffered from a critical heart disease. 639 (57%) were admitted to the Center and the rest died in provincial hospitals with but not always from a heart disease found at autopsy. An additional 43 (6.2%) patients had nonstructural heart disease and 12 (1.7%) had heart diseases not considered to be critical. The total incidence of critical heart disease fluctuated from 2.15 to 2.51/1,000 live births without any well-defined trend. A decrease in the relative frequency throughout the 5-year period was found for common arterial trunk, pulmonary stenosis and atresia while an increase was observed in patency of the arterial duct. The most frequent critical heart diseases in infancy were: ventricular septal defect (18.2%) - mostly in isolation; complete transposition (14.6%); aortic coarctation (10.0%); hypoplastic left heart syndrome (9.1%) and pulmonary atresia (6.3%). The majority (51.4%) of patients became critically ill or died in the neonatal period. The most common conditions seen in neonates were complete transposition (22.5%), hypoplastic left heart syndrome (16.1%) and coarctation of the aorta (9.5%). The highest share of critically ill patients was encountered in complete transposition (100%), pulmonary atresia (98.7%), common arterial trunk (97.4%) and double outlet right ventricle (92.1%). The least dangerous were atrial septal defect (6.6%), pulmonary stenosis (7.0%), aortic stenosis (12.2%) and ventricular septal defect (21.0%). The mean age was 76 (+/- 56) days at admission and 59 (+/- 73) days at death. Urgent cardiovascular surgery was performed in 235 (36.8%) of the 639 patients admitted in infancy, that is 0.5 per 1,000 live born children. 相似文献
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Ho-Jong Kim Daehee Kim Suyong Jung Myung-Ho Bae Sam Nyung Yi Kenji Watanabe Takashi Taniguchi Soo Kyung Chang Dong Han Ha 《RSC advances》2018,8(23):12900
We investigated the homogeneity and tolerance to heat of monolayer MoS2 using photoluminescence (PL) spectroscopy. For MoS2 on SiO2, the PL spectra of the basal plane differ from those of the edge, but MoS2 on hexagonal boron nitride (h-BN) was electron-depleted with a homogeneous PL spectra over the entire area. Annealing at 450 °C rendered MoS2 on SiO2 homogeneously electron-depleted over the entire area by creating numerous defects; moreover, annealing at 550 °C and subsequent laser irradiation on the MoS2 monolayer caused a loss of its inherent crystal structure. On the other hand, monolayer MoS2 on h-BN was preserved up to 550 °C with its PL spectra not much changed compared with MoS2 on SiO2. We performed an experiment to qualitatively compare the binding energies between various layers, and discuss the tolerance of monolayer MoS2 to heat on the basis of interlayer/interfacial binding energy.We investigated the homogeneity and tolerance to heat of monolayer MoS2 using photoluminescence (PL) spectroscopy. 相似文献
88.
Optimized isolation and expansion of human airway epithelial basal cells from endobronchial biopsy samples 下载免费PDF全文
Kate H.C. Gowers Robert E. Hynds Ricky M. Thakrar Bernadette Carroll Martin A. Birchall Sam M. Janes 《Journal of tissue engineering and regenerative medicine》2018,12(1):e313-e317
Autologous airway epithelial cells have been used in clinical tissue‐engineered airway transplantation procedures with a view to assisting mucosal regeneration and restoring mucociliary escalator function. However, limited time is available for epithelial cell expansion due to the urgent nature of these interventions and slow epithelial regeneration has been observed in patients. Human airway epithelial cells can be expanded from small biopsies or brushings taken during bronchoscopy procedures, but the optimal mode of tissue acquisition from patients has not been investigated. Here, we compared endobronchial brushing and endobronchial biopsy samples in terms of their cell number and their ability to initiate basal epithelial stem cell cultures. We found that direct co‐culture of samples with 3T3‐J2 feeder cells in culture medium containing a Rho‐associated protein kinase inhibitor, Y‐27632, led to the selective expansion of greater numbers of basal epithelial stem cells during the critical early stages of culture than traditional techniques. Additionally, we established the benefit of initiating cell cultures from cell suspensions, either using brushing samples or through enzymatic digestion of biopsies, over explant culture. Primary epithelial cell cultures were initiated from endobronchial biopsy samples that had been cryopreserved before the initiation of cell cultures, suggesting that cryopreservation could eliminate the requirement for close proximity between the clinical facility in which biopsy samples are taken and the specialist laboratory in which epithelial cells are cultured. Overall, our results suggest ways to expedite epithelial cell preparation in future airway cell therapy or bioengineered airway transplantation procedures. 相似文献
89.
Daniel Joseph Jody A. Vogel C. Sam Smith Whitney Barrett Gary Bryskiewicz Aaron Eberhardt 《Prehospital emergency care》2018,22(4):427-435
Background: Excessive alcohol consumption is associated with a substantial number of emergency department visits annually and is responsible for a significant number of lives lost each year in the United States. However, a minimal amount is known about the impact of alcohol on the EMS system. Objectives: The primary objective was to determine the proportion of 9-1-1 calls in Denver, Colorado in which (1) alcohol was a contributing factor or (2) the individual receiving EMS services had recently ingested alcohol. The secondary objectives were to compare the characteristics of EMS calls and to estimate the associated costs. Methods: This was a prospective observational cohort study of EMS calls for adults from July 1, 2012, to June 30, 2014. Primary outcomes for the study were alcohol as a contributing factor to the EMS call and recent alcohol consumption by the patient receiving EMS services. Logistic regression was utilized to determine the associations between EMS call characteristics and the outcomes. Cost was estimated using historic data. Results: During the study period, 169,642 EMS calls were completed by the Denver Health Paramedic Division. Of these 71% were medical and 29% were trauma-related. The median age was 45 (interquartile range [IQR] 29–59) years, and 55% were male. 50,383 calls (30%) had alcohol consumption, and 49,165 (29%) had alcohol as a contributing factor. Alcohol related calls were associated with male sex, traumatic injuries including head trauma, emergent response, use of airway adjuncts, cardiac monitoring, glucose measurement, use of restraints, use of spinal precautions, and administration of medications for sedation. Estimated costs to the EMS system due to alcohol intoxication exceeded $14 million dollars over the study period and required in excess of 37 thousand hours of paramedic time. Conclusions: Compared to 9-1-1 calls that do not involve alcohol, alcohol-related calls are more likely to involve male patients, emergent response, traumatic injuries, advanced monitoring, airway adjuncts, and medications for sedation. This represents a significant burden on the emergency system and society. Further studies are needed to evaluate whether additional interventions such as social services could be used to lessen this burden. 相似文献
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