Health and equity implications of individual adaptation to air pollution in a changing climate.

Future climate change can cause more days with poor air quality. This could trigger more alerts telling people to stay inside to protect themselves, with potential consequences for health and health equity. Here, we study the change in US air quality alerts over this century due to fine particulate matter (PM2.5), who they may affect, and how they may respond. We find air quality alerts increase by over 1 mo per year in the eastern United States by 2100 and quadruple on average. They predominantly affect areas with high Black populations and leakier homes, exacerbating existing inequalities and impacting those less able to adapt. Reducing emissions can offer significant annual health benefits ($5,400 per person) by mitigating the effect of climate change on air pollution and its associated risks of early death. Relying on people to adapt, instead, would require them to stay inside, with doors and windows closed, for an extra 142 d per year, at an average cost of $11,000 per person. It appears likelier, however, that people will achieve minimal protection without policy to increase adaptation rates. Boosting adaptation can offer net benefits, even alongside deep emission cuts. New adaptation policies could, for example: reduce adaptation costs; reduce infiltration and improve indoor air quality; increase awareness of alerts and adaptation; and provide measures for those working or living outdoors. Reducing emissions, conversely, lowers everyone's need to adapt, and protects those who cannot adapt. Equitably protecting human health from air pollution under climate change requires both mitigation and adaptation.

Morphological, anatomical, and transcriptomics analysis reveals the regulatory mechanisms of cassava plant height development.

BACKGROUND: Cassava is one of three major potato crops and the sixth most important food crop globally. Improving yield remains a primary aim in cassava breeding. Notably, plant height significantly impacts the yield and quality of crops; however, the mechanisms underlying cassava plant height development are yet to be elucidated. RESULTS: In this study, we investigated the mechanisms responsible for cassava plant height development using phenotypic, anatomical, and transcriptomic analyses. Phenotypic and anatomical analysis revealed that compared to the high-stem cassava cultivar, the dwarf-stem cassava cultivar exhibited a significant reduction in plant height and a notable increase in internode tissue xylem area. Meanwhile, physiological analysis demonstrated that the lignin content of dwarf cassava was significantly higher than that of high cassava. Notably, transcriptome analysis of internode tissues identified several differentially expressed genes involved in cell wall synthesis and expansion, plant hormone signal transduction, phenylpropanoid biosynthesis, and flavonoid biosynthesis between the two cassava cultivars. CONCLUSIONS: Our findings suggest that internode tissue cell division, secondary wall lignification, and hormone-related gene expression play important roles in cassava plant height development. Ultimately, this study provides new insights into the mechanisms of plant height morphogenesis in cassava and identifies candidate regulatory genes associated with plant height that can serve as valuable genetic resources for future crop dwarfing breeding.

Estimating Air Change Rate in Mechanically Ventilated Classrooms Using a Single CO2 Sensor and Automated Data Segmentation.

With a growing emphasis on indoor air quality (IAQ) in educational environments, CO2 monitoring in classrooms has become commonplace. CO2 data can be used to estimate outdoor air change rate (ACH) based on the mass balance principle, which can be further linked to human health, performance, and building energy consumption. This study used a novel machine learning method to automatically segment CO2 concentration time series data into build-up, equilibrium, and decay periods, and then estimated classroom ACH using the corresponding CO2 mass balance equations. This method, applied to 40 classrooms in two mechanically ventilated K-6 schools, generated up to ten ACH estimates per day per classroom. A comparison with ACH calculated using the mechanical ventilation rates with 100% outdoor air reported by the building automation system during the study period reveals a slight underestimation by the decay and build-up methods, while the equilibrium method produced closer estimates. These differences may be attributed to uncertainties in occupancy, activity, CO2 emission rates, and air mixing. This research underscores the potential of leveraging CO2 data for more comprehensive IAQ assessments and highlights the challenges associated with accurately estimating ACH in real-world settings.

Transcriptome analysis reveals the effect of propyl gallate on kiwifruit callus formation.

KEY MESSAGE: Exploring the potential action mechanisms of reactive oxygen species during the callus inducing, they can activate specific metabolic pathways in explants to regulate callus development. Reactive oxygen species (ROS) play an important role in the regulation of plant growth and development, but the mechanism of their action on plant callus formation remains to be elucidated. To address this question, kiwifruit was selected as the explant for callus induction, and the influence of ROS on callus formation was investigated by introducing propyl gallate (PG) as an antioxidant into the medium used for inducing callus. The results have unveiled that the inclusion of PG in the medium has disturbed the equilibrium of ROS during the formation of the kiwifruit callus. We selected the callus that was induced by the addition of 0.05 mmol/L PG to the MS medium. The callus exhibited a significant difference in the amount compared to the control medium without PG. The callus induced by the MS medium without PG was used as the control for comparison. KEGG enrichment indicated that PG exposure resulted in significant differences in gene expression in related pathways, such as phytohormone signaling and glutathione in kiwifruit callus. Weighted gene co-expression analysis indicated that the pertinent regulatory networks of both ROS and phytohormone signaling were critical for the establishment of callus in kiwifruit leaves. In addition, during the process of callus establishment, the ROS level of the explants was also closely related to the genes for transmembrane transport of substances, cell wall formation, and plant organ establishment. This investigation expands the theory of ROS-regulated callus formation and presents a new concept for the expeditious propagation of callus in kiwifruit.

Emergency Knowledge Translation, COVID-19 and indoor air: evaluating a virtual ventilation and filtration consultation program for community spaces in Ontario.

BACKGROUND: An October, 2021 review of Public Health Ontario's COVID-19 guidance for congregate settings such as shelters and long-term care homes demonstrated that this guidance did not include references to ventilation or filtration. In April 2022, an interdisciplinary team with expertise in indoor air quality (IAQ), engineering, epidemiology, community programming and knowledge translation launched a virtual ventilation and filtration consultation program for community spaces in Toronto, Ontario. The program gives people working in community spaces direct access to IAQ experts through 25-min online appointments. The program aims to help reduce the risk of COVID-19 transmission in community spaces, and was designed to help compensate for gaps in public health guidance and action. METHODS: Representatives from participating organizations (n. 27) received a link to an online survey via email in April 2023. Survey questions explored the impacts of the program on topics such as: purchase and use of portable air filters; maintenance and use of bathroom fans; and, maintenance and modification of HVAC systems. Survey participation was anonymous, and no demographic information was collected from participants. RESULTS: Representatives from 11 organizations completed the survey (40%). Of those who responded, nine (82%) made changes as a result of the program, with eight (73%) making two or more changes such as purchasing portable air filters and increasing routine maintenance of HVAC systems. CONCLUSIONS: When presented with brief access to expert support and tailored plain language guidance, people working in community spaces increased their use of ventilation and filtration strategies for COVID-19 infection prevention and control.

The role of implicit theories of intelligence and personality in older adults' resilience: cognitive functioning and social participation as two mediators.

OBJECTIVES: Resilience during old age reflects the capacity to adapt to changes and challenges associated with normative aging and is an important component of successful aging. Belief in the incremental theory of intelligence and personality could help older adults maintain cognitive functioning and social engagement, which may further contribute to their resilience. The current study investigated how implicit theories of intelligence and personality affected older adults' resilience and examined cognitive functioning and social participation as two mediators. METHOD: A total of 108 older adults aged 60-92 were recruited and completed relevant scales and cognitive tasks. Path analyses were conducted to estimate the expected mediation model. RESULTS: The incremental theory of intelligence, but not personality, was positively related to older adults' resilience. Both cognitive functioning and social participation mediated the effect of the implicit theory of intelligence in the model without covariates. When background variables were controlled, the mediation effect of cognitive functioning remained significant, while the link between the implicit theory of intelligence and social participation was weakened. CONCLUSION: Older adults' implicit theory of intelligence plays a significant role in fostering resilience in late adulthood, especially through maintaining older adults' cognitive functioning.

Hedgehog signal activates AMPK via Smoothened to promote autophagy and lipid degradation in hepatocytes.

Studies in the past decade have shown that lipid droplets stored in liver cells under starvation are encapsulated by autophagosomes and fused to lysosomes via the endocytic system. Autophagy responds to a variety of environmental factors inside and outside the cell, so it has a complex signal regulation network. To this end, we first explored the role of Hedgehog (Hh) in autophagy and lipid metabolism. Treatment of normal mouse liver cells with SAG and GDC-0449 revealed elevated phosphorylation of AMP-activated protein kinase (AMPK) and increased lipidation of LC3. SAG, and GDC-0449 were agonist and antagonist of Smoothened (Smo) in canonical Hh pathway, respectively, but they played a consistent role in the regulation of autophagy in hepatocytes. Moreover, SAG and GDC-0449 did not affect the expression of glioma-associated oncogene (Gli1) and patched 1, suggesting the absence of canonical Hh signaling in hepatocytes. We further knocked down the Smo and found that the effects of SAG and GDC-0449 disappeared, indicating that the non-canonical Smo pathway was involved in the regulation of autophagy in hepatocytes. In addition, SAG and GDC-0449 promoted lipid degradation and inhibited lipid production signals. Knockdown of Smo slowed down the rate of lipid degradation rather than Sufu or Gli1, indicating that Hh signaling regulated the lipid metabolism via Smo. In summary, activates AMPK via Smo to promote autophagy and lipid degradation.

Intralesional diode laser pretreatment facilitates surgery for orbital venous malformations: initial experience with 23 consecutive patients.

PURPOSE: This study aims to evaluate the efficacy and safety of intralesional diode laser pretreatment for facilitating surgery for orbital venous malformations (OVMs). METHODS: This is a retrospective, non-comparative, interventional cohort involving 23 consecutive OVM patients undergoing intralesional laser pretreatment followed by surgical excision. The main outcome measures included volumetric changes, exophthalmometry, cosmesis, and symptom scores as well as treatment-related adverse events. RESULTS: Following intralesional diode laser, the mean volume dropped significantly from 2366 ± 1887 to 129 ± 119 mm3 (t = 5.716; p < 0.001). After a single treatment session, a mean 90 ± 13% volume shrinkage was achieved in all 23 OVM. The mean Hertel exophthalmometry decreased significantly from 14 ± 3 to 13 ± 1 mm (t = 2.515; P < 0.02). The resolution of periocular dyschromasia and swelling were evident in 20 patients (87%). Symptom scores improved significantly from 6.5 ± 1.4 (very intense discomfort or effect on daily living) to 1.2 ± 1.0 (very mild discomfort or effect on daily living; p < 0.001). Short-term bruises and swelling were reported in 20 patients (87%). CONCLUSION: Intralesional laser pretreatment is effective to facilitate surgery especially for the deep involving orbital venous malformations.

Effects of ultrasound-guided alveolar recruitment manoeuvres compared with sustained inflation or no recruitment manoeuvres on atelectasis in laparoscopic gynaecological surgery as assessed by ultrasonography: a randomized clinical trial.

BACKGROUND: The majority of patients may experience atelectasis under general anesthesia, and the Trendelenburg position and pneumoperitoneum can aggravate atelectasis during laparoscopic surgery, which promotes postoperative pulmonary complications. Lung recruitment manoeuvres have been proven to reduce perioperative atelectasis, but it remains controversial which method is optimal. Ultrasonic imaging can be conducive to confirming the effect of lung recruitment manoeuvres. The purpose of our study was to assess the effects of ultrasound-guided alveolar recruitment manoeuvres by ultrasonography on reducing perioperative atelectasis and to check whether the effects of recruitment manoeuvres under ultrasound guidance (visual and semiquantitative) on atelectasis are superior to sustained inflation recruitment manoeuvres (classical and widely used) in laparoscopic gynaecological surgery. METHODS: In this randomized, controlled, double-blinded study, women undergoing laparoscopic gynecological surgery were enrolled. Patients were randomly assigned to receive either lung ultrasound-guided alveolar recruitment manoeuvres (UD group), sustained inflation alveolar recruitment manoeuvres (SI group), or no RMs (C group) using a computer-generated table of random numbers. Lung ultrasonography was performed at four predefined time points. The primary outcome was the difference in lung ultrasound score (LUS) among groups at the end of surgery. RESULTS: Lung ultrasound scores in the UD group were significantly lower than those in both the SI group and the C group immediately after the end of surgery (7.67 ± 1.15 versus 9.70 ± 102, difference, -2.03 [95% confidence interval, -2.77 to -1.29], P < 0.001; 7.67 ± 1.15 versus 11.73 ± 1.96, difference, -4.07 [95% confidence interval, -4.81 to -3.33], P < 0.001;, respectively). The intergroup differences were sustained until 30 min after tracheal extubation (9.33 ± 0.96 versus 11.13 ± 0.97, difference, -1.80 [95% confidence interval, -2.42 to -1.18], P < 0.001; 9.33 ± 0.96 versus 10.77 ± 1.57, difference, -1.43 [95% confidence interval, -2.05 to -0.82], P < 0.001;, respectively). The SI group had a significantly lower LUS than the C group at the end of surgery (9.70 ± 1.02 versus 11.73 ± 1.96, difference, -2.03 [95% confidence interval, -2.77 to -1.29] P < 0.001), but the benefit did not persist 30 min after tracheal extubation. CONCLUSIONS: During general anesthesia, ultrasound-guided recruitment manoeuvres can reduce perioperative aeration loss and improve oxygenation. Furthermore, these effects of ultrasound-guided recruitment manoeuvres on atelectasis are superior to sustained inflation recruitment manoeuvres. TRIAL REGISTRATION: Chictr.org.cn, ChiCTR2100042731, Registered 27 January 2021, www.chictr.org.cn .

Assessing the fractionation and bioavailability of heavy metals in soil-rice system and the associated health risk.

This study developed a method to build relationships between chemical fractionations of heavy metals in soils and their accumulations in rice and estimate the respective contribution of each geochemical speciation in the soils from the Yangtze River Delta, China. In contaminated areas, residue and humic acid-bound fractions in soils were the main phases for most heavy metals. The mobility of heavy metals was in this following order: Cd > Pb ≈ Zn > Ni > As ≈ Cr > Hg. Transfer factors calculated by the ratios of specific fractionations of heavy metals in the soil-rice system were used to assess the capability of different metal speciation transfer from soil to rice. The carbonate and Fe/Mn oxyhydroxides bound phase had significant positive correlations with total metal concentrations in rice. Hg uptake by rice might be related to the exchangeable and carbonate-bound fractions of soil Hg. Results of PCA analysis of transfer factors estimated that the labile fractions (i.e. water soluble, exchangeable and carbonate bound) contributed more than 40% of the heavy metal accumulations in rice. Effect of organic matter and residue fraction on metals transfer was estimated to be ~ 25 to ~ 30% while contribution of humic acid and Fe/Mn oxyhydroxides-bound fractions was estimated to be ~ 20 to ~ 30%. Modified risk assessment code (mRAC) and ecological contamination index (ECI) confirmed that the soil samples were polluted by heavy metals. Soil Cd contributed more than 80% of mRAC. Contrarily, the main contributors to ECI were identified as As, Hg, Pb and Zn. The average values of total target hazard quotient (TTHQ) and Risktotal were above 1 and 10-4 respectively, implying people living in the study area were exposed to both non-carcinogenic and carcinogenic risk. As and Pb were the main contributor to high TTHQ value while As, Cd and Cr in rice contributed mostly to Risktotal value. Spatial changes of ecological risk indexes and human health risk indexes showed that the samples with high TTHQ values distributed in the area with high values of mRAC. Likewise, the area with high ECI values and with high carcinogenic risk overlapped.

State relationship orientation and helping behaviors: the influence of hunger and trait relationship orientations.

Exchange orientation (EO) and communal orientation (CO) are two fundamental relationship orientations (ROs). We argue that state RO (i.e., the relative activation of the two ROs at a specific moment) varies across situations and should be differentiated from trait ROs. In two studies, we examined how state RO affected subsequent helping behaviors and how it was influenced by a situational factor (i.e., hunger). We also examined whether trait ROs moderated the above links. An eye-tracking paradigm (Study 1) and a scenario-based paradigm (Study 2) were adopted to assess state RO. The two studies consistently found that relatively more activation of state EO over state CO reduced helping tendency toward strangers (Study 1) and acquaintances (Study 2). High trait CO amplified the effect in Study 1. Moreover, hunger heightened the relative activation of state EO over state CO in both studies, but the effect was only significant for participants with high trait EO in Study 1. The results highlight the importance to study the momentary variation of ROs and open new research directions. Supplementary information: The online version contains supplementary material available at 10.1007/s12144-022-03666-y.

Biochemical mechanisms of rhizospheric Bacillus subtilis-facilitated phytoextraction by alfalfa under cadmium stress - Microbial diversity and metabolomics analyses.

The effects of Bacillus subtilis inoculation on the growth and Cd uptake of alfalfa were evaluated in this research using pot experiments, and the relevant biochemical mechanisms were first investigated by combined microbial diversity and nontarget metabolomics analyses. The results indicated that inoculation with alfalfa significantly decreased the amount of plant malondialdehyde (MDA) and improved the activities of plant antioxidant enzymes and soil nutrient cycling-involved enzymes, thereby promoting biomass by 29.4%. Inoculation also increased Cd bioavailability in rhizosphere soil by 12.0% and Cd removal efficiency by 139.3%. The biochemical mechanisms included enhanced bacterial diversity, transformed microbial community composition, regulated amounts of amino acids, fatty acids, carbohydrates, flavonoids and phenols in rhizosphere soil metabolites, and modulations of the corresponding Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. These responses were beneficial to microbial activity, nutrient cycling, and Cd mobilization, detoxification, and decontamination by alfalfa in soil. This study, especially the newly identified differential metabolites and metabolic pathways, provides new insights into mechanism revelation and strategy development in microbe-assisted phytomanagement of heavy metal-contaminated soils.

Unraveling the direct and indirect effects between future time perspective and subjective well-being across adulthood.

OBJECTIVES: While the socioemotional selectivity theory (SST) argues for a negative relationship between future time perspective (FTP) and subjective well-being (SWB), empirical studies have found contradictory results. The current study resolved the controversy by examining the indirect effect between FTP and SWB through preference of life goals. Age differences in the mediation effects were also tested. METHOD: A total of 432 participants were surveyed for their FTP, life goals, depression, life satisfaction, and demographical background. The three components of FTP, extension (FTE), opportunity (FTO), and constraint (FTC), were examined respectively. Regression based mediation models were estimated to test the direct and indirect effects between FTP components and SWB. Moderated mediation models were adopted to test age differences in the above effects. RESULTS: Opposite direct and indirect effects between FTP components and SWB were identified. FTE and FTO were related to relatively fewer present-focused life goals, and then to lower life satisfaction and higher depression. However, FTE and FTO were directly related to higher life satisfaction. FTC was not significantly related to preference of life goals but had a direct positive effect with depression. Moreover, older age attenuated the positive direct effect between FTO and life satisfaction, as well as the negative effect between preference to present-focused goals and depression. CONCLUSION: The results highlight the critical role of life goal preference for understanding the complex relationship between FTP and subjective well-being. The differential effects of the three FTP components also suggest the importance to examine each component individually in future studies.

Benefits of volunteering on psychological well-being in older adulthood: evidence from a randomized controlled trial.

Objectives: Long-term volunteering has been associated with better physical, mental, and cognitive health in correlational studies. Few studies, however, have examined the longitudinal benefits of volunteering with randomized experimental designs (e.g., intervention studies). Even fewer studies have examined whether such benefits can be shown after short-term volunteering. To fill this gap, we conducted four 1-hour volunteering intervention sessions to promote volunteering among a group of older adults with limited volunteering experience and examined the impact of volunteering on depressive symptoms, meaning in life, general self-efficacy, and perceived autonomy.Methods: A total of 384 participants aged 50-96 years were assigned at random to either an intervention group to promote volunteering behaviors or an active control group to promote physical activity. The participants' monthly volunteering minutes, depressive symptoms, meaning in life, general self-efficacy and perceived autonomy were measured at baseline and six weeks, three months, and six months after the intervention.Results: Being in the volunteering intervention condition was not directly associated with depressive symptoms, meaning in life, general self-efficacy, or perceived autonomy at the 6-week, 3-month, or 6-month follow-ups after the intervention. However, there was an indirect effect of the intervention on depressive symptoms: participants in the intervention group, who had increased their volunteering at the 3-month follow-up, reported fewer depressive symptoms at the 6-month follow-up.Discussion: Our randomized controlled trial suggests that short-term volunteering does not reliably lead to short-term changes in psychosocial health measures as correlational studies would suggest. Efforts need to be made to encourage older adults to maintain long-term volunteering.

Limb Remote Ischemic Preconditioning Applied During Sevoflurane Anesthesia Does Not Protect the Lungs in Patients Undergoing Adult Heart Valve Surgery.

BACKGROUND: Two consistent overall cell protective preconditioning treatments should provide more protection. We hypothesized that limb remote ischemic preconditioning (RIPC, second preconditioning stimulus) applied during sevoflurane inhalation (first preconditioning stimulus) would provide more protection to the lungs of patients undergoing adult heart valve surgery. METHODS: In this randomized, placebo-controlled, double-blind trial, 50 patients were assigned to the RIPC group or the placebo group (1:1). Patients in the RIPC group received three 5-min cycles of 300 mmHg cuff inflation/deflation of the left-side lower limb before aortic cross-clamping. Anesthesia consisted of opioids and propofol for induction and sevoflurane for maintenance. The primary end point was comparison of the postoperative arterial-alveolar oxygen tension ratio (a/A ratio) between groups. Secondary end points included comparisons of pulmonary variables, postoperative morbidity and mortality and regional and systemic inflammatory cytokines between groups. RESULTS: In the RIPC group, the a/A ratio and other pulmonary variables exhibited no significant differences throughout the study period compared with the placebo group. No significant differences in either plasma or bronchoalveolar lavage levels of TNF- α were noted between the groups at 10 min after anesthetic induction and 1 h after cross-clamp release. The percentage of neutrophils at 12 h postoperation was significantly increased in the RIPC group compared with the placebo group (91.34±0.00 vs. 89.42±0.10, P = 0.023). CONCLUSIONS: Limb RIPC applied during sevoflurane anesthesia did not provide additional significant pulmonary protection following adult valvular cardiac surgery.

In situ efficiency of filters in residential central HVAC systems.

High-efficiency filtration in residential forced-air heating, ventilation, and air conditioning (HVAC) systems protects equipment and can reduce exposure to particulate matter. Laboratory tests provide a measure of the nominal efficiency, but they may not accurately reflect the in situ efficiency of the filters because of variations in system conditions and changes in filter performance over time. The primary focus of this paper is to evaluate the effective filtration efficiency, which is inclusive of any loading and system impacts, in 21 occupied residential homes through in-duct concentration measurements. We considered the role of filter media by testing both electret and non-electret media, as well as the role of loading by considering new and used filters. The results show that filters with higher nominal efficiency generally had higher effective filtration efficiency in the same home. In terms of performance change, there is no significant difference in efficiency between initial and 3-month non-electret filters, but the efficiency of electret filters generally decreased over time. However, both nominal efficiency and performance change were vastly overshadowed by the wide variety in loading and system conditions across homes, making it hard to predict filter efficiency in a given home without in situ measurements.

Study protocol of a multi-center RCT testing a social-cognitive intervention to promote volunteering in older adults against an active control.

BACKGROUND: Volunteering could be a win-win opportunity for older adults: Links between volunteering and societal improvements as well as older adults' own health and longevity are found in several observational studies. RCTs to increase volunteering in older adults are however sparse, leaving the question of causality unanswered. This study protocol describes a theory-based social-cognitive intervention with multiple behavior change techniques to increase volunteering among community-dwelling older adults in Hong Kong. METHODS: In a parallel group, two-arm, randomized controlled trial, an initial N = 360 are assigned to receive either the volunteering intervention or the active control intervention (parallel content targeting physical activity). The primarily outcome measure is self-reported volunteering minutes per month at baseline, six weeks, three months and six months after the intervention. Participants in the treatment group are expected to increase their weekly volunteering minutes over time as compared to participants in the control group. Possible active ingredients of the intervention as well as mental and physical health outcomes of increased volunteering are investigated by means of mediation analyses. DISCUSSION: Like many industrialized nations, Hong Kong faces a rapid demographic change. An effective psychological intervention to encourage retirees to engage in formal volunteering would alleviate some of the societal challenges a growing proportion of older adults entails. TRIAL REGISTRATION: Primary Registry and Trial Identifying Number ChiCTR-IIC-17010349 , secondary CCRB trial number CUHK_CCRB00543, registration date 2016/12/28.

miR-494 Sensitizes Gastric Cancer Cells to TRAIL Treatment Through Downregulation of Survivin.

BACKGROUND/AIMS: TNF-related apoptosis-inducing ligand (TRAIL) is a novel and low-toxic anti-tumor drug used for various cancers. However, cancer cells usually develop mechanisms to acquire the resistance against TRAIL. Among these changes, dysregulation of microRNAs (miRNAs) usually occurs in cancer cells and is responsible for induction of drug resistance. METHODS: Expression of miR-494 in gastric cancer tissues and cell lines was detected by quantitative reverse transcriptase real time PCR (qRT-PCR) analysis. Effect of miR-494 on regulating the TRAIL sensitivity to gastric cancer cell lines was evaluated by MTT assays. Bioinformatics and luciferase reporter assays were used to confirm the regulation of miR-494 on survivin. Mitochondrial apoptosis pathway in gastric cancer cells was tested by western blot and flow cytometry analysis. RESULTS: Obvious downregulation of miR-494 was observed in gastric cancer cells. Furthermore, we found that expression profile of miR-494 was associated with TRAIL-sensitivity in gastric cancer. Enforced expression of miR-494 was found to sensitize the gastric cancer cells to TRAIL-induced cytotoxicity. Mechanically, Luciferase reporter assays proved that survivin was the target of miR-494 in gastric cancer cells. Enforced expression of miR-494 decreased the expression of survivin, and thus promoted the TRAIL-induced mitochondria collapse and apoptosis pathway. CONCLUSION: MiR-494/survivin axis represents a potential mechanism which is responsible for TRAIL resistance in gastric cancer cells. Increasing the miR-494 expression may serve as a novel therapeutic strategy to sensitize gastric cancer cells to TRAIL treatment.

Occurrence, sources and health risk of polycyclic aromatic hydrocarbons in soils around oil wells in the border regions between oil fields and suburbs.

The Yellow River Delta (YRD) is a typical region where oil fields generally overlap cities and towns, leading to complex soil contamination from both the oil fields and human activities. To clarify the distribution, speciation, potential sources and health risk of polycyclic aromatic hydrocarbons (PAHs) in soils of border regions between oil fields and suburbs of the YRD, 138 soil samples (0-20 cm) were collected among 12 sampling sites located around oil wells with different extraction histories. The 16 priority control PAHs (16PAHs), as selected by the United States Environmental Protection Agency (USEPA), were extracted via an accelerated solvent extraction and detected by GC-MS. The results showed that soils of the study area were generally polluted by the 16PAHs. Among these pollutions, chrysene and phenanthrene were the dominant components, and 4-ring PAHs were the most abundant. A typical temporal distribution pattern of the 16PAHs was revealed in soils from different sampling sites around oil wells with different exploitation histories. The concentrations of total 16PAHs and high-ring PAHs (HPAHs) both increased with the extraction time of the nearby oil wells. Individual PAH ratios and PCA method revealed that the 16PAHs in soil with newly developed oil wells were mainly from petroleum pollutants, whereas PAHs in soils around oil wells with a long exploitation history were probably from petroleum contamination; combustion of petroleum, fuel, and biomass; and degradation and migration of PAHs from petroleum. Monte Carlo simulation was used to evaluate the health risks of the 7 carcinogenic PAHs and 9 non-carcinogenic PAHs in the study area. The results indicated that ingestion and dermal contact were the predominant pathways of exposure to PAH residues in soils. Both the carcinogenic and non-carcinogenic burden of the 16PAHs in soils of the oil field increased significantly with exploitation time of nearby oil wells.

Multivariate linear regression model for source apportionment and health risk assessment of heavy metals from different environmental media.

The study evaluated source apportionment of heavy metals in vegetable samples from the potential sources of fertilizer, water and soil samples collected along the Changjiang River delta in China. The results showed that 25.72% of vegetable samples (Brassica chinensis L.) containing Pb, and Cd, Cu, Hg and Zn at relatively serious levels were from soil. Combined with principle component analysis (PCA) and cluster analysis (CA), the results of the spatial distribution of heavy metals in different environmental media indicated that fertilizer, water and soil were the main sources of heavy metals in vegetables. The results of multivariate linear regression (MLR) using partition indexes (P) showed that fertilizer contributed to 38.5%, 40.56%, 46.01%, 53.34% and 65.25% of As, Cd, Cu, Pb and Zn contents in vegetables, respectively. In contrast, 44.58% of As, 32.57% of Hg and 32.83% of Pb in vegetables came from soil and 42.78% of Cd and 66.97% of Hg contents in vegetables came from the irrigation water. The results of PCA and CA verified that MLR using P was suitable for determining source apportionment in a vegetable. A health risk assessment was performed; As, Cd and Pb contributed to more than 75% of the total hazard quotient (THQ) values and total carcinogenic risk values (Risktotal) for adults and children through oral ingestion. More than 70% of the estimated THQ and Risktotal is contributed by water and fertilizer. Therefore, it is necessary to increase efforts in screening limits/levels of heavy metals in fertilizer and irrigation water and prioritize appropriate pollution management strategies.