Evolution of Ozone Formation Sensitivity during a Persistent Regional Ozone Episode in Northeastern China and Its Implication for a Control Strategy.

In recent years, the magnitude and frequency of regional ozone (O3) episodes have increased in China. We combined ground-based measurements, observation-based model (OBM), and the Weather Research and Forecasting and Community Multiscale Air Quality (WRF-CMAQ) model to analyze a typical persistent O3 episode that occurred across 88 cities in northeastern China during June 19-30, 2021. The meteorological conditions, particularly the wind convergence centers, played crucial roles in the evolution of O3 pollution. Daily analysis of the O3 formation sensitivity showed that O3 formation was in the volatile organic compound (VOC)-limited or transitional regime at the onset of the pollution episode in 92% of the cities. Conversely, it tended to be or eventually became a NOx-limited regime as the episode progressed in the most polluted cities. Based on the emission-reduction scenario simulations, mitigation of the regional O3 pollution was found to be most effective through a phased control strategy, namely, reduction of a high ratio of VOCs to NOx at the onset of the pollution and lower ratio during evolution of the O3 episode. This study presents a new possibility for regional O3 pollution abatement in China based on a reasonable combination of OBM and the WRF-CMAQ model.

Evaluating the performance and influencing factors of three portable black carbon monitors for field measurement.

Black carbon (BC) is associated with adverse human health and climate change. Mapping BC spatial distribution imperatively requires low-cost and portable devices. Several portable BC monitors are commercially available, but their accuracy and reliability are not always satisfactory during continuous field observation. This study evaluated three models of portable black carbon monitors, C12, MA350 and DST, and investigates the factors that affect their performance. The monitors were tested in urban Beijing, where portable devices running for one month alongside a regular-size reference aethalometer AE33. The study considers several factors that could influence the monitors' performance, including ambient weather, aerosol composition, loading artifacts, and built-in algorithms. The results show that MA350 and DST present considerable discrepancies to the reference instrument, mainly occurring at lower concentrations (0-500 ng/m3) and higher concentrations (2500-8000 ng/m3), respectively. These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST. The study also suggests that the ambient environment has limited influence on the monitors' performance, but loading artifacts and accompanying compensation algorithms can result in unrealistic data. Based on the evaluation, the study suggests that C12 is the best choice for unsupervised field measurement, DST should be used in scenarios where frequent maintenance is available, and MA350 is suitable for research purposes with post-processing applicable. The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms.

Strong bacterial stochasticity and fast fungal turnover in Taihu Lake sediments, China.

Understanding the assembly and turnover of microbial communities is crucial for gaining insights into the diversity and functioning of lake ecosystems, a fundamental and central issue in microbial ecology. The ecosystem of Taihu Lake has been significantly jeopardized due to urbanization and industrialization. In this study, we examined the diversity, assembly, and turnover of bacterial and fungal communities in Taihu Lake sediment. The results revealed strong bacterial stochasticity and fast fungal turnover in the sediment. Significant heterogeneity was observed among all sediment samples in terms of environmental factors, especially ORP, TOC, and TN, as well as microbial community composition and alpha diversity. For instance, the fungal richness index exhibited an approximate 3-fold variation. Among the environmental factors, TOC, TN, and pH had a more pronounced influence on the bacterial community composition compared to the fungal community composition. Interestingly, species replacement played a dominant role in microbial beta diversity, with fungi exhibiting a stronger pattern. In contrast, stochastic processes governed the community assembly of both bacteria and fungi, but were more pronounced for bacteria (R2 = 0.7 vs. 0.5). These findings deepen the understanding of microbial assembly and turnover in sediments under environmental stress and provide essential insights for maintaining the multifunctionality of lake ecosystems.

Cause of PM2.5 pollution during the 2016-2017 heating season in Beijing, Tianjin, and Langfang, China.

To investigate the cause of fine particulate matter (particles with an aerodynamic diameter less than 2.5 µm, PM2.5) pollution in the heating season in the North China Plain (specifically Beijing, Tianjin, and Langfang), water-soluble ions and carbonaceous components in PM2.5 were simultaneously measured by online instruments with 1-hr resolution, from November 15, 2016 to March 15, 2017. The results showed extreme severity of PM2.5 pollution on a regional scale. Secondary inorganic ions (SNA, i.e., NO3-+SO42+ NH4+) dominated the water-soluble ions, accounting for 30%-40% of PM2.5, while the total carbon (TC, i.e., OC + EC) contributed to 26.5%-30.1% of PM2.5 in the three cities. SNA were mainly responsible for the increasing PM2.5 pollution compared with organic matter (OM). NO3- was the most abundant species among water-soluble ions, but SO42- played a much more important role in driving the elevated PM2.5 concentrations. The relative humidity (RH) and its precursor SO2 were the key factors affecting the formation of sulfate. Homogeneous reactions dominated the formation of nitrate which was mainly limited by HNO3 in ammonia-rich conditions. Secondary formation and regional transport from the heavily polluted region promoted the growth of PM2.5 concentrations in the formation stage of PM2.5 pollution in Beijing and Langfang. Regional transport or local emissions, along with secondary formation, made great contributions to the PM2.5 pollution in the evolution stage of PM2.5 pollution in Beijing and Langfang. The favourable meteorological conditions and regional transport from a relatively clean region both favored the diffusion of pollutants in all three cities.

Physical-Chemical Composition and Quality Related Changes in "Ruaner" Pear (Pyrus ussuriensis) During Freezing-Thawing Period.

"Ruaner" pear (Pyrus ussuriensis Maxim.) is a fruit crop that is frequently served frozen in China. It is a typical postharvest ripening fruit that needs to ripen after harvest before it can be eaten, and freezing-thawing is one way that pears are treated during postharvest ripening. In order to study the physical-chemical composition and quality-related changes in "Ruaner" pears that result the freezing-thawing period, "Ruaner" pears were kept in a freezer (-20 °C) for 7 days, after which they were transferred to room temperature for thawing. The color of the peel of the "Ruaner" pears changed from yellow-green to yellow and then brown. The chlorophyll content and titratable acidity (TA) decreased significantly throughout 0-12 h period. The carotenoid content tended to rise and then decrease, peaking at 3 h after thawing (HAT), while the soluble solids content (SSC), firmness, total phenolic content, and total flavonoid content all generally decreased. The composition of soluble sugars and organic acids was examined in "Ruaner" pears, and the major soluble sugars were fructose and glucose, with citric acid being the most abundant organic acid. The data suggest that freezing-thawing significantly changes firmness, water content, SSC, and TA in "Ruaner" pears. At 3-4 HAT, "Ruaner" pears have moderate hardness, high water content, low acid content, and higher total phenolic, total flavonoid, and soluble solids content. Therefore, 3-4 HAT is the best time for pears in terms of both table and processing quality.

The Changes in Color, Soluble Sugars, Organic Acids, Anthocyanins and Aroma Components in "Starkrimson" during the Ripening Period in China.

"Starkrimson" is a traditional apple cultivar that was developed a long time ago and was widely cultivated in the arid region of the northern Wei River of China. However, little information regarding the quality characteristics of "Starkrimson" fruit has been reported in this area. To elucidate these characteristics, the color, soluble sugars, organic acids, anthocyanins and aroma components were measured during the ripening period through the use of high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The results indicated that the changes in anthocyanin contents took place later than the changes in the Commission International Eclairage (CIE) parameters. Meanwhile, cyanidin 3-galactoside (cy3-gal), fructose, sucrose, glucose and malic acid were the primary organic compounds, and 1-butanol-2-methyl-acetate, 2-hexenal and 1-hexanol were the most abundant aroma components in the skin. Furthermore, rapidly changing soluble sugars and organic acid synchronization took place in the early ripening period, while rapidly changing aroma components occurred later, on the basis of fresh weight. This result suggested that the production of aroma components might be a useful index of apple maturity.

Molecular Identification of Diphyllobothrium nihonkaiense from 3 Human Cases in Heilongjiang Province with a Brief Literature Review in China.

Human diphyllobothriasis is a widespread fish-borne zoonosis caused by the infection with broad tapeworms belonging to the genus Diphyllobothrium. In mainland China, so far 20 human cases of Diphyllobothrium infections have been reported, and the etiologic species were identified as D. latum and D. nihonkaiense based on morphological characteristics or molecular analysis. In the present study, proglottids of diphyllobothriid tapeworms from 3 human cases that occurred in Heilongjiang Province, China were identified as D. nihonkaiense by sequencing mitochondrial cytochrome c oxidase subunit I (cox1) and NADH dehydrogenase subunit 5 (nad5) genes. Two different cox1 gene sequences were obtained. One sequence showed 100% homology with those from humans in Japan. The remaining cox1 gene sequence and 2 different nad5 gene sequences obtained were not described previously, and might reflect endemic genetic characterizations. D. nihonkaiense might also be a major causative species of human diphyllobothriasis in China. Meanwhile, the finding of the first pediatric case of D. nihonkaiense infection in China suggests that infants infected with D. nihonkaiense should not be ignored.

Urinary perchlorate exposure and risk in women of reproductive age in a fireworks production area of China.

Perchlorate is used widely in fireworks, and, if ingested, it has the potential to disrupt thyroid function. The concentrations of perchlorate in water and soil samples and in urine samples of women of reproductive age from Liuyang, the largest fireworks production area in China, were investigated. The results showed that the average perchlorate concentrations in groundwater, surface water, farmland soil, and urine samples of women from the fireworks production area were significantly greater than those from the control area. The health risk of perchlorate ingested through drinking water was assessed based on the mode recommended by the United States Environmental Protection Agency. The values of hazard quotient of river water and groundwater in the fireworks production area were much greater than the safe level (=1), which indicates that adverse health effects may result from perchlorate when these sources of water are used as drinking water. These results indicated that the environment of the fireworks production area has been polluted by perchlorate and that residents were and are facing greater exposure doses of perchlorate. Fireworks production enterprises may be a major source of perchlorate contamination.

[Spatial and Temporal Distribution Characteristics of Ozone Concentration and Health Benefit Assessment in the Beijing-Tianjin-Hebei Region from 2015 to 2020].

To evaluate the spatial and temporal distribution characteristics of ambient ozone (O3) in the Beijing-Tianjin-Hebei (BTH) Region, the land use regression (LUR) model and random forest (RF) model were used to simulate the ambient O3 concentration from 2015 to 2020. Meanwhile, all-cause, cardiovascular, and respiratory mortalities as well as economic losses attributed to O3 were also estimated. The results showed that upward trends with fluctuation were observed for ambient O3 concentration, mortalities, and economic losses attributable to O3 exposure in the BTH Region from 2015 to 2020. The areas with high O3 concentration and great changes were concentrated in the central and southwestern regions, whereas the concentration in the northern region was low, and the change degree was small. The spatial distribution of the mortalities was also consistent with the spatial distribution of O3 concentration. From 2015 to 2020, the economic losses regarding all-cause mortality and cardiovascular mortality increased in 13 cities of the BTH Region, whereas the economic losses of respiratory mortality decreased in 4 cities in the BTH Region. The results indicated that the priority areas for O3 control were not uniform. Specifically, Beijing, Tianjin, Hengshui, and Xingtai were vital areas for O3 pollution control in the BTH Region. Differentiated control measures should be adopted based on the characteristics of these target areas to decline O3 concentration and reduce health impacts and economic losses associated with O3 exposure.

Pyramidal neurons proportionately alter the identity and survival of specific cortical interneuron subtypes.

The mammalian cerebral cortex comprises a complex neuronal network that maintains a delicate balance between excitatory neurons and inhibitory interneurons. Previous studies, including our own research, have shown that specific interneuron subtypes are closely associated with particular pyramidal neuron types, forming stereotyped local inhibitory microcircuits. However, the developmental processes that establish these precise networks are not well understood. Here we show that pyramidal neuron types are instrumental in driving the terminal differentiation and maintaining the survival of specific associated interneuron subtypes. In a wild-type cortex, the relative abundance of different interneuron subtypes aligns precisely with the pyramidal neuron types to which they synaptically target. In Fezf2 mutant cortex, characterized by the absence of layer 5 pyramidal tract neurons and an expansion of layer 6 intratelencephalic neurons, we observed a corresponding decrease in associated layer 5b interneurons and an increase in layer 6 subtypes. Interestingly, these shifts in composition are achieved through mechanisms specific to different interneuron types. While SST interneurons adjust their abundance to the change in pyramidal neuron prevalence through the regulation of programmed cell death, parvalbumin interneurons alter their identity. These findings illustrate two key strategies by which the dynamic interplay between pyramidal neurons and interneurons allows local microcircuits to be sculpted precisely. These insights underscore the precise roles of extrinsic signals from pyramidal cells in the establishment of interneuron diversity and their subsequent integration into local cortical microcircuits.

Fruit coloration and anthocyanin biosynthesis after bag removal in non-red and red apples (Malus × domestica Borkh.).

In the present study, evolution of apple color (L* and a/b), the accumulation of anthocyanins and the activity of the related enzymes, phenylalanine ammonia-lyase (PAL), chalcone isomerase (CHI), dihydroflavonol4-reductase (DFR) and UDP-Glucose: flavonoid-3-O-galactosyl transferase (UFGT), were investigated in bagged non-red apple cultivars ('Granny Smith' and 'Golden Delicious') and red apple cultivars ('Starkrimon' and 'Pink Lady'). Young fruits were bagged 40-45 days after flowering (DAF), and fruits of 'Golden Delicious' and 'Starkrimon' were uncovered and exposed to light 120 DAF, while those of 'Granny Smith' and 'Pink Lady' were exposed for 160 DAF. Results showed that cyanidin 3-galactoside (cy3-gal) was the most abundant anthocyanin in both non-red and red cultivars. Level of anthocyanins was higher in 'Granny Smith' than in 'Golden Delicious', indicating that red color was easier to develop in green cultivar 'Granny Smith' than in yellow cultivar 'Golden Delicious' after bag removal. The cy3-gal accumulation of non-red cultivars tested was not significantly correlated with PAL, CHI and DFR activity, but was significantly correlated with UFGT activity. During the reddening of non-red apples, UFGT may be the more important factor in the anthocyanin biosynthesis.

Assessment of toxic mechanisms and mode of action to three different levels of species for 14 antibiotics based on interspecies correlation, excess toxicity, and QSAR.

Antibiotics have received much attention owing to their ecotoxicity toward nontarget aquatic creatures. However, the mode of action (MOA) of toxicity against nontarget organisms is unclear in some aquatic organisms. In this study, the comparison of toxicities through interspecies correlations, excess toxicity calculated from toxicity ratio, and quantitative structure-activity relationship (QSAR) was carried out to investigate the MOAs for 14 antibiotics among Daphnia magna, Vibrio fischeri, and Pseudokirchneriella subcapitata. The results showed that interspecies toxicity correlations were very poor between any two of the three species for the 14 antibiotics. The toxicity ratio revealed that most antibiotics exhibited excess toxicity to algae and Daphnia magna but not to V. fischeri, demonstrating that some antibiotics share the same MOA, but some antibiotics share different MOAs among the three different levels of species. P. subcapitata was the most sensitive species, and V. fischeri was the least sensitive species. This is because of the differences in the biouptake and interactions of antibiotics with the target receptors between the three different trophic levels of the species. Molecular docking simulations suggested that the toxicity of antibiotics depends highly on their interactions with target receptors through hydrogen bonds, electrostatic or polar interactions, π bond interactions, and van der Waals forces. QSAR models demonstrated that hydrogen bonding and electrophilicity/nucleophilicity play key roles in the interaction of antibiotics with different receptors in the three species. The toxic mechanisms of antibiotics are attributed to the interactions between electrophilic antibiotics and biological nucleophiles, and hydrogen-bond interactions. These results are valuable for understanding the toxic mechanisms and MOA of the three different levels of species.

[Distribution and Potential Ecological Risk Assessment of Heavy Metals in Sediments of Lake Qinghai].

Lake Qinghai is the largest closed saltwater lake in China. In recent years, because of the rapid development of industry, agriculture, and tourism, the lake has been increasingly affected by human activities, which has attracted the attention of many scholars. In order to understand the distribution of heavy metals in the surface sediments of Lake Qinghai, the contents of Zn, Cu, Pb, Co, Ni, As, Cd, and Cr were investigated, the metal fractions were extracted, and the sources, as well as potential ecological risks, were analyzed. The results showed that:① the ω(As) (13.21 mg·kg-1) and ω(Cd) (0.21 mg·kg-1) in the surface sediments of Lake Qinghai were 1.13 and 1.53 times higher than the environmental background values, respectively, and the other heavy metal contents were all lower than the environmental background values. There were similar spatial distribution characteristics of analyzed metals except for As, with higher values measured in the northwestern area of the lake and the 151 Terminal. ② Except for Cd, the analyzed heavy metals mainly existed in the form of the residual state; by contrast, Cd mainly existed in the form of the bioavailable state, which has high potential toxicity to aquatic organisms. ③ Combined with the results of the correlation and principal component analysis, the metals including Zn, Cu, Pb, Co, Ni, Cd, and Cr were thought to mainly come from the natural environment, whereas the source of As was related to human activities, such as agricultural production. ④ According to potential risk analyses, the average of the metal potential ecological risk factors was 76.57, which indicated a slight ecological hazard level. However, it should be noted that the potential ecological hazard level and release risk of Cd at each site were higher than those of the other metals, especially in the regions nearing the estuary of Heima River, Lake Gahai, and the sand island, which showed higher levels of enrichment and potential release risk. Therefore, further attention should be paid to the potential impacts of Cd in sediments of these regions on the water environment and ecosystem.

Decade-long trends in chemical component properties of PM2.5 in Beijing, China (2011-2020).

A 10-year-long measurement of water-soluble inorganic ions in PM2.5 was made in Beijing from June 2011 to December 2020, to investigate the interannual trends of chemical characteristics of PM2.5 and to provide insights into the future prevention and control of PM2.5 pollution. From 2011 to 2020, with the implementation of strict air pollution control strategies, significant changes of PM2.5 have been observed in Beijing, with NO3-, SO42- and NH4+ decreasing at rates of 5.10, 8.80 and 7.64% yr-1 respectively. The percentages of NO3- and SO42- under elevated pollution levels were investigated. When PM2.5 values fell in the range of 0-400 µg m-3, NO3-/ SO42- values were mostly higher than 1 and showed upward trends from 2011 to 2020. However, under extremely heavy haze conditions, SO42- dominated PM2.5 formation. This result was closely related to the change characteristics of the oxidation ratio of sulfate (SOR), the oxidation ratio of nitrate (NOR) and gaseous precursors under different pollution levels. The change characteristics of NOR and SOR under elevated PM2.5 levels indicated that the aqueous phase oxidation was the key process driving SO42- formation; while as for NO3-, in addition to the availability of NH4+, the atmospheric oxidation capacity made crucial roles. The analysis of typical haze episodes during the past decade indicated that the emission reduction of gaseous pollutants, especially SO2, made great contributions to the improved PM2.5 air quality in Beijing. We highlighted that future efforts should focus on enhanced reduction of NO2 emission and control of atmospheric oxidation capacity to further reduce particulate nitrate formation.

Dramatic changes in aerosol composition during the 2016-2020 heating seasons in Beijing-Tianjin-Hebei region and its surrounding areas: The role of primary pollutants and secondary aerosol formation.

With the implementation of a series of air pollution mitigation strategies during the past decade, great air quality improvements have been observed in the BTH region. Despite of significant decreases in gaseous pollutants, such as SO2 and NO2, the enhancement of secondary aerosol formation was observed. NO3- has surpassed SO42- and OM to become the dominant PM2.5 component. We find that the reduction of POC mainly dominated the decreasing trend of OC. As for secondary inorganic components, the key processes or factors controlling the spatial-temporal variation characteristics were different. The areas with large SO42- concentrations corresponded well to those with high SO2 concentrations, while the synchronized NO3- better followed spatial patterns in O3 than NO2. From 2016 to 2020, the response of SO42- to SO2 was close to a linear function, while the reaction of NO3- to the decrease of NO2 displayed nonlinear behavior. Such different relationships indicated that SO42- was predominantly controlled by SO2, while NO3- was not only related to NO2 but also determined by the secondary conversion process. The ratios of SO42-, NO3-, NH4+, and OC to EC between 2016 and 2020 were generally higher than 1 in typical BTH cities, and the ratio of NO3- to EC was exceptionally high, with a range reaching up to 200 %. Besides, this ratio coincided well with the enhancement of Ox, indicating the potential role of Ox to secondary NO3- formation. The diurnal cycle of NO3-, O3, and NO2 concentration change rate indicated that the relative increase of O3 during nighttime may offset the effectiveness of NOX emission reduction. This study provided observational evidence of enhanced secondary NO3- formation with the rising trend of atmospheric oxidation and emphasized the importance of nighttime chemistry for NO3- formation in the BTH region.

Paeoniflorin alleviates inflammatory response in IBS-D mouse model via downregulation of the NLRP3 inflammasome pathway with involvement of miR-29a.

Paeoniflorin has been traditionally used to treat pain and immunologic derangement in China. However, its detailed mechanism remains to be illuminated. We investigated the mechanism by which paeoniflorin alleviates the inflammatory response in a mouse model of irritable bowel syndrome with predominant diarrhea (IBS-D). C57BL/6 wild type (WT) and miR-29a knockout (KO) mice were randomly divided into control, model, rifaximin, and paeoniflorin groups (n = 7). IBS-D model was induced by single intracolonic instillation of 0.1 mL trinitro-benzene-sulfonic acid (TNBS, 50 mg/mL) combined with restraint stress for seven consecutive days. The treatment groups received rifaximin (100 mg/kg) and paeoniflorin (50 mg/kg) via intragastric administration for seven days, respectively. The results showed that the fecal water content, fecal pellet output, visceral sensitivity, and histopathological score after paeoniflorin treatment were lower than those of the model group in both WT and miR-29a KO mice (P < 0.05). In both lineage mice, damage was observed in the colon tissues of model group, while paeoniflorin treatment partially ameliorated the tissue damage. Serum levels of DAO, DLA, IL-1ß, IL-18, TNF-α, and MPO were decreased after paeoniflorin treatment (P < 0.05), with miR-29a KO mice in a lower level compared with that of WT mice. RT-PCR showed that the relative expression of miR-29a, NF-κB (p65), NLRP3, ASC, caspase-1, IL-1ß, and TNF-α was downregulated while NKRF was upregulated after paeoniflorin treatment (P < 0.05). Immunohistochemistry showed that intestinal epithelial protein levels of NLRP3, ASC, and caspase-1 decreased while those of Claudin-1 and ZO-1 increased in the paeoniflorin treatment group (P < 0.05). In general, compared with WT mice, NLRP3 inflammasome pathway targets was in much lower expression level than miR-29a KO mice. In conclusion, paeoniflorin could inhibit abnormal activation of the NLRP3 inflammasome pathway by inhibiting miR-29a in IBS-D, thereby relieving the inflammatory response of the intestinal mucosa and reconstructing the intestinal epithelial barrier.

LncRNA MALAT1 induced by hyperglycemia promotes microvascular endothelial cell apoptosis through activation of the miR-7641/TPR axis to exacerbate neurologic damage caused by cerebral small vessel disease.

BACKGROUND: This study aimed to explore the effect of hyperglycemia-induced long noncoding RNA (lncRNA) metastasis-associated lung carcinoma transcript 1 (MALAT1) on microvascular endothelial cell activity. In addition, we investigated the possible downstream molecular regulatory mechanism in order to provide an adjunctive therapeutic target for the prognostic nerve recovery of cerebral small vessel disease (CSVD). METHODS: A rat model of diabetes was induced by streptozotocin (STZ) injection in combination with a high-energy diet. The mixed model of CSVD and hyperglycemia was prepared by injection of homologous microemboli in vitro. Results of 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay and enzyme-linked immunosorbent assay (ELISA) showed that the inhibition of lncRNA MALAT1 by siRNA in a high-glucose environment effectively alleviated the cell damage caused by high glucose (HG) and reduced the rate of apoptosis. We found that the upregulation of downstream miR-7641 and TPR (translocated promoter region) reduced the occurrence of cell damage and apoptosis. RESULTS: The results of neurological deficit score showed that the scores of ICH group, HG group and HG + ICH group were significantly higher than those of Sham group, and the differences were statistically significant. The qPCR results showed that the MALAT1 level of the model group was significantly different from that of the sham group, and the expression levels of damage markers vWF and ICAM-1 were detected by Western blot (WB), which were significantly higher in the model group than in the sham group. The MTT cell activity assay showed that the addition of miR-7641 inhibitor or TPR short hairpin RNA (shRNA) into normally cultured cells reduced cell activity. ELISA results showed that low expression of miR-7641 increased the apoptosis rate of microvascular endothelial cells. Western blot (WB) results showed that the protein expression levels of BAX and cleaved caspase-3 (c-caspase-3) were negatively correlated with miR-7641. The regulation of TPR expression showed similar results. CONCLUSIONS: High blood glucose level induced the increase of lncRNA MALAT1 and regulated the expression of TPR by activating miR-7641 to promote the initiation of apoptosis of microvascular endothelial cells, aggravating the neurological dysfunction caused by CSVD.

Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China.

To control the spread of the 2019 novel coronavirus (COVID-19), China imposed nationwide restrictions on the movement of its population (lockdown) after the Chinese New Year of 2020, leading to large reductions in economic activities and associated emissions. Despite such large decreases in primary pollution, there were nonetheless several periods of heavy haze pollution in eastern China, raising questions about the well-established relationship between human activities and air quality. Here, using comprehensive measurements and modeling, we show that the haze during the COVID lockdown was driven by enhancements of secondary pollution. In particular, large decreases in NOx emissions from transportation increased ozone and nighttime NO3 radical formation, and these increases in atmospheric oxidizing capacity in turn facilitated the formation of secondary particulate matter. Our results, afforded by the tragic natural experiment of the COVID-19 pandemic, indicate that haze mitigation depends upon a coordinated and balanced strategy for controlling multiple pollutants.

[Schisandrin B prevents doxorubicin-induced cardiotoxicity in rabbits].

OBJECTIVE: To study the effect of dexrazoxane in preventing doxorubicin-induced cardiotoxicity in rabbit-models and its mechanism. METHODS: Thirty one New Zealand white rabbits were randomly divided into two groups, doxorubicin (DOX) group and doxorubicin + dexrazoxane group. The cardiotoxicity was assessed by measuring serum superoxide dismutase (SOD), malondialdehyde (MDA), cardiac troponin I (cTnI), brain natriuretic peptide (BNP), left ventricular ejection function (LVEF), and left ventricular fractional shortening (LVFS), before and 4 and 10 weeks after intervention. Pathological changes in cardiac tissues and the apoptosis of myocardial cells were examined at the end of the experiment. Results Doxorubicin increased serum MDA, cTnI and BNP and decreased SOD, LVEF and LVFS (P < 0.05). Dexrazoxane (DEX) inhibited the increase of MDA, cTnI and BNP, and the decrease of LVEF and LVFS (P < 0.05). The rabbits treated with doxorubicin + dexrazoxane had slighter pathological changes in myocardium and apoptotic myocardial cells than those treated with DOX. CONCLUSION: Dexrazoxane prevents doxorubicin-induced cardiotoxicity through decreasing oxygen free radical production, cutting down lipid peroxidation, and depressing cardiocyte apoptosis.

[Chemical Composition Characteristics and Source Apportionment of PM2.5 During the Heating Period of 2016-2017 in the Eastern Part of the North China Plain].

To study the composition characteristics and source apportionment of PM2.5 in the eastern part of the North China Plain, manual samples during the two-year heating period of 2016 and 2017 were collected in seven cities, including Hengshui, Cangzhou, Ji'nan, Dezhou, Binzhou, Zibo, and Liaocheng. The results showed that the average values of ρ(PM2.5) during the observation periods were 137.23 µg·m-3 and 111.83 µg·m-3, respectively, which exceeded the daily average secondary standard limit of GB 3095-2012 "Environmental Air Quality Standard" by 1.8 and 1.5 times, respectively. The mean mass of water-soluble ions accounted for 53.32% and 47.04% of ρ(PM2.5), respectively, of which SNA (NO3-, SO42-, and NH4+) were the main ions. During the 2016 and 2017 observation periods, NO3-/SO42- increased from 1.35 to 1.60, while the concentration of Cl- decreased, indicating a decrease in the impact of coal burning. The proportions of secondary organic carbon (SOC) in organic carbon (OC) were 71.63% and 55.35%, respectively, indicating the source of secondary organic carbon had decreased. Analysis of characteristic elements Fe/Al and Ba/Ni showed that dust sources and vehicle sources had increased significantly. The backward trajectories of air mass results showed that the polluted air mass mainly came from the northwest direction during the observation period. However, the PM2.5 concentration was highest when the air mass came from the Anhui and Jiangsu provinces.