The air pollution tradeoff in India: Saving more lives versus reducing the inequality of exposure

Chronic exposure to ambient fine particulate matter (PM2.5) represents one of the largest global public health risks, leading to millions of premature deaths annually. For a country facing high and spatially variable exposures, prioritizing where to reduce PM2.5 concentrations leads to an inherent tradeoff between saving the most lives and reducing inequality of exposure. This tradeoff results from the shape of the concentration-response function between exposure to PM2.5 and mortality, which indicates that the additional lives saved per unit reduction in PM2.5 declines as concentrations increase. We estimate this concentration-response function for urban areas of India, finding that a 10 unit reduction in PM2.5 in already-clean locations will reduce the mortality rate substantially (4.2% for a reduction from 30 to 20 µgm-3), while a 10 unit reduction in the dirtiest locations will reduce mortality only modestly (1.2% for a reduction from 90 to 80 µgm-3). We explore the implications of this PM2.5/mortality relationship by considering a thought experiment. If India had a fixed amount of resources to devote to PM2.5 concentration reductions across urban areas, what is the lives saved/inequality of exposure tradeoff from three different methods of employing those resources? Across our three scenarios—1) which reduces exposures for the dirtiest districts, 2) which reduces exposures everywhere equally, and 3) which reduces exposures to save the most lives—scenario 1 saves 18,000 lives per year while reducing the inequality of exposure by 65%, while scenario 3 saves 126,000 lives per year, but increases inequality by 19%.

Anti-Colonization Effect of Au Surfaces with Self-Assembled Molecular Monolayers Functionalized with Antimicrobial Peptides on S. epidermidis

Medical devices with an effective anti-colonization surface are important tools for combatting healthcare-associated infections. Here, we investigated the anti-colonization efficacy of antimicrobial peptides covalently attached to a gold model surface. The gold surface was modified by a self-assembled polyethylene glycol monolayer with an acetylene terminus. The peptides were covalently connected to the surface through a copper-catalyzed [3 + 2] azide-acetylene coupling (CuAAC). The anti-colonization efficacy of the surfaces varied as a function of the antimicrobial activity of the peptides, and very effective surfaces could be prepared with a 6 log unit reduction in bacterial colonization.

The impact of chemosensory dysfunctions on weight loss

Background: The role of chemosensory senses (olfaction, taste, and trigeminal) is crucial, and their dysfunctions profoundly affect the quality of life, potentially impacting eating behaviors. However, it is unclear which chemosensory symptoms could lead to undernutrition. This study aims to investigate which findings in patients' smell and taste workup are predictors of weight loss. Methods: This is a retrospective study based on a validated questionnaire consecutively given to adult patients presented in smell and taste consultations during a 10-year period. Psychophysical tests were used to measure chemosensory function (Sniffin' Sticks, taste powder, and Taste Strips tests). Results: We included 555 patients (307 females) with a median age of 51 years (IQR 23). Among them, 76 (13.7%) reported involuntary weight loss due to chemosensory disorders occurred over periods ranging from 3 to 36 months. We found that the odds of losing weight were 2.1 times higher when patients reported changes in aroma perception (p-value=0.012; 95% CI 1.15 - 3.83). Parosmia, but not phantosmia nor smell loss, was a significant predictor of weight loss (OR 2.22; p-value=0.015; 95% CI 1.17 - 4.2). Furthermore, the duration of symptoms for more than two years was protective for weight loss (OR 0.44; p-value=0.014; 95% CI 0.23 - 0.85). Regarding putative etiologies, post-traumatic chemosensory dysfunction was also a significant predictor (OR 2.08; p-value=0.039; 95% CI 1.04 - 4.16). Concerning psychophysical tests, we found that the probability of a patient to present weight loss increased by 8% for every 1-unit reduction in Taste Strips score (p-value=0.006; 95% CI 0.87 - 0.98). Conclusion: We recommend investigating weight loss in smell and taste consultations, especially when patients report changes in aroma perception, parosmia, duration of symptoms for less than two years, head injury, and when low Taste Strips score is measured.

Environmental Injustice and Industrial Chicken Farming in Maryland

Maryland’s growing chicken industry, including concentrated animal feeding operations (CAFOs) and meat processing plants, raises a number of concerns regarding public health and environmental justice. Using hot spot analysis, we analyzed the totality of Maryland’s CAFOs and meat processing plants and those restricted to the Eastern Shore to assess whether communities of color and/or low socioeconomic status communities disproportionately hosted these types of facilities at the census tract level. We used zero-inflated regression modeling to determine the strength of the associations between environmental justice variables and the location of CAFOs and meatpacking facilities at the State level and on the Eastern Shore. Hot spot analyses demonstrated that CAFO hot spots on the Eastern Shore were located in counties with some of the lowest wealth in the State, including the lowest ranking county—Somerset. Zero-inflated regression models demonstrated that increases in median household income across the state were associated with a 0.04-unit reduction in CAFOs. For every unit increase in the percentage of people of color (POC), there was a 0.02-unit increase in meat processing facilities across the state. The distribution of CAFOs and meat processing plants across Maryland may contribute to poor health outcomes in areas affected by such production, and contribute to health disparities and health inequity.

Effect of adjunct thoracoplasty on Adolescent Idiopathic Scoliosis patients’ 3D back contour

The aims of this study were to evaluate the effect of a thoracoplasty procedure in addition to a posterior spinal fusion and instrumentation on an Adolescent Idiopathic Scoliosis (AIS) patient’s 3D back contour as measured by surface topography. We performed a retrospective review to identify patients who were treated with posterior spinal fusion with spinal instrumentation and those who were treated with an additional thoracoplasty procedure. We analyzed changes in surface topography measurements between these two groups using t-test and ANCOVA statistical analyses. Although there were no statistically significant differences in 11 of 12 variables, thoracoplasty-posterior spinal fusion (n=10) group had a mean 6.6 unit reduction in trunk asymmetry while the posterior spinal fusion group (n=26) had a mean 22.8 unit reduction in trunk asymmetry (p-value<0.05). The posterior spinal fusion group and thoracoplasty-posterior spinal fusion group were not shown to have clinically significant differences in 3D back contour correction. An additional thoracoplasty procedure does not provide better correction in the transverse plane and in fact had a smaller degree of trunk asymmetry correction. This supports the current trends of decreasing use of thoracoplasty in AIS patients to address severe rib hump deformities given concerns for decreased post-operative lung function and alternative methods of vertebral body derotation, such as thoracic pedicle screws.

Lung function and peak oxygen uptake in chronic obstructive pulmonary disease phenotypes with and without emphysema

Previous studies of associations of forced expiratory lung volume in one second (FEV1) with peak oxygen uptake (VO2peak) in chronic obstructive pulmonary disease (COPD) have not taken sex, age and height related variance of dynamic lung volumes into account. Nor have such demographic spread of spirometric measures been considered in studies comparing VO2peak between COPD phenotypes characterized by degree of emphysema. We aimed to assess the association of FEV1Z-score with VO2peak in COPD (n = 186) and investigate whether this association differs between emphysema (E-COPD) and non-emphysema (NE-COPD) phenotypes. Corresponding assessments using standardized percent predicted FEV1 (ppFEV1) were performed for comparison. Additionally, phenotype related differences in VO2peak were compared using FEV1Z-score and ppFEV1 as alternative expressions of FEV1. E-COPD and NE-COPD were defined by transfer factor of the lung for carbon monoxide below and above lower limits of normal (LLN), respectively. The associations were assessed in linear regression models. One unit reduction in FEV1Z-score was associated with 1.9 (95% CI 1.4, 2.5) ml/kg/min lower VO2peak. In stratified analyses, corresponding estimates were 2.2 (95% CI 1.4, 2.9) and 1.2 (95% CI 0.2, 2.2) ml/kg/min lower VO2peak in E-COPD and NE-COPD, respectively. The association did not differ statistically by COPD phenotype (p-value for interaction = 0.153). Similar estimates were obtained in analyses using standardized ppFEV1. Compared to NE-COPD, VO2peak was 2.2 (95% CI 0.8, 3.6) and 2.1 (95% CI 0.8, 3.5) ml/kg/min lower in E-COPD when adjusted for FEV1Z-score and ppFEV1, respectively. In COPD, FEV1Z-score is positively associated with VO2peak. This association was stronger in E-COPD but did not differ statistically by phenotype. Both the association of FEV1 with VO2peak and the difference in VO2peak comparing COPD phenotypes seems independent of sex, age and height related variance in FEV1. Mechanisms leading to reduction in FEV1 may contribute to lower VO2peak in E-COPD.

Antibiofilm and Protein-Repellent Polymethylmethacrylate Denture Base Acrylic Resin for Treatment of Denture Stomatitis

Candida albicans (C. albicans) biofilm is a common etiological factor in denture stomatitis. The purpose of this study was to investigate the effects of incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC) as a protein repellent into a new high-impact denture acrylic (HIPA) resin on the surface roughness, solution pH, and C. albicans biofilm adhesion to the denture base. The new acrylic denture resin base was formulated by mixing MPC into HIPA resin at mass fractions of 1.5%, 3%, and 4.5%. Surface roughness was measured using a Mitutoyo surface roughness tester. C. albicans biofilm growth and viability were assessed via colony forming unit counts. The pH of the biofilm growth medium was measured using a digital pH meter. Adding MPC to the HIPA resin at percentages of 1.5% and 3% increased the roughness values significantly (p < 0.05), while adding 4.5% MPC resulted in no difference in roughness values to that of the control group (p > 0.05). All experimental groups demonstrated neutral pH values (pH ≅ 7) and were not significantly different from each other (p > 0.05). Incorporating 2-methacryloyloxyethyl phosphorylcholine at 4.5% resulted in a significant (≅1 log) colony-forming unit reduction compared with the control group with 0% MPC (p < 0.05). A fungal-retarding denture acrylic resin was developed through the incorporation of MPC for its protein-repelling properties. This newly developed denture acrylic material has the potential to prevent oral microbial infections, such as denture stomatitis.

How does air pollution affect housing rental prices in Chile? An economic assessment of PM2.5 concentration across Chilean communes

This paper addresses a serious environmental concern in Chile: PM2.5 concentration, a health threat especially affecting the population living in the central and southern communes of Chile. Using housing data for 312 spatial units, along with interpolation techniques to predict air pollution for communes with missing information, we find that, on average, 1 μg/m3 increase in PM2.5 produces a decrease of 4.1 per cent in housing rental prices. These estimates also show an important upward bias in the estimated coefficient when the endogeneity of air pollution is not addressed. An average Chilean household would be willing to pay US$12.31 per month for a one-unit reduction in PM2.5 concentration. Similar monetary values have been found in previous studies for both México and Chile. As with PM2.5 concentration, the average marginal willingness to pay exhibits marked differences across communes. From these results, the study addresses some policy implications and proposes avenues for future research.

Trade Liberalization and Productivity Growth: Firm-Level Analysis from Kenya

We analyze the impact of trade liberalization on firm productivity growth in Kenya’s manufacturing sector, using a panel spanning 8 years; 1992-1999. Our analysis reveals that liberalizing trade generates high productivity improvements in the manufacturing sector. We find that a one-unit reduction in import duties as a percentage of total imports significantly increases firm-level productivity in the manufacturing sector by 5.7%. When we examine this effect on the firm’s share of exported output, we find that lowering of import duties significantly increases the share of output exported by 0.7%. Further, we sought to assess how the effect of import duties varied across the different industries in our sample. Examining the effect of import duties on industrial performance, we find a negative and statistically significant relationship in some of the industries. Our results show heterogeneous effect of reduction of import duties on industrial performance. Not all industries benefited from the lowering of import duties, especially the food and bakery, and garment industry, where productivity did not increase. These findings have important policy implications for improving the manufacturing sector. Consequently, formulating policies that effectively relax restrictive barriers to trade in the economy could speed up firm-level productivity in the manufacturing sector.

Multi-targeted gene silencing strategies inhibit replication of Canine morbillivirus

Background Canine morbilivirus (canine distemper virus, CDV) is a highly contagious pathogen associated with high morbidity and mortality in susceptible carnivores. Although there are CDV vaccines available, the disease poses a huge threat to dogs and wildlife hosts due to vaccine failures and lack of effective treatment. Thus, the development of therapeutics is an urgent need to achieve rapid outbreak control and reduce mortality in target species. Gene silencing by RNA interference has emerged as a promising therapeutic approach against different human and animal viruses. In this study, plasmid-based short hairpin RNAs (shRNAs) against three different regions in either CDV nucleoprotein (N), or large polymerase (L) genes and recombinant adenovirus-expressing N-specific multi-shRNAs were generated. Viral cytopathic effect, virus titration, plaque-forming unit reduction, and real-time quantitative RT-PCR analysis were used to check the efficiency of constructs against CDV. Results In CDV-infected VerodogSLAM cells, shRNA-expressing plasmids targeting the N gene markedly inhibited the CDV replication in a dose-dependent manner, with viral genomes and titers being decreased by over 99%. Transfection of plasmid-based shRNAs against the L gene displayed weaker inhibition of viral RNA level and virus yield as compared to CDV N shRNAs. A combination of shRNAs targeting three sites in the N gene considerably reduced CDV RNA and viral titers, but their effect was not synergistic. Recombinant adenovirus-expressing multiple shRNAs against CDV N gene achieved a highly efficient knockdown of CDV N mRNAs and successful inhibition of CDV replication. Conclusions We found that this strategy had strong silencing effects on CDV replication in vitro. Our findings indicate that the delivery of shRNAs using plasmid or adenovirus vectors potently inhibits CDV replication and provides a basis for the development of therapeutic strategies for clinical trials.