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As the top emitter of carbon dioxide worldwide, China faces a considerable challenge in reducing carbon emissions to combat global warming. Carbon emissions from coal consumption is the primary source of carbon dioxide emissions in China. The decomposition of the driving factors and the quantification of regions and industries needs further research. Thus, this paper decomposed five driving factors affecting carbon emissions from coal consumption in China, namely, carbon emission intensity, energy structure, energy intensity, economic output, and population scale, by constructing a Kaya-Logarithmic Mean Divisia Index (Kaya-LMDI) decomposition model with data on coal consumption in China from 1997 to 2019. It was revealed that the economic output and energy intensity effects are major drivers and inhibitors of carbon emissions from coal consumption in China, respectively. The contribution and impact of these driving factors on carbon emissions from coal consumption were analyzed for different regions and industrial sectors. The results showed that carbon emissions from coal consumption increased by 3211.92 million tons from 1997 to 2019. From a regional perspective, Hebei Province has the most significant impact on carbon emissions from coal consumption due to the effect of economic output. Additionally, the industrial sector had the most pronounced influence on carbon emissions from coal consumption due to the economic output effect. Finally, a series of measures to reduce carbon emissions including controlling the total coal consumption, improving the utilization rate of clean energy, and optimizing the energy structure is proposed based on China's actual development. [ABSTRACT FROM AUTHOR]

Colistin is the last line of defense for the treatment of multidrug-resistant gram-negative bacterial infections. However, colistin resistance is gradually increasing worldwide, with resistance commonly regulated by two-component system and mcr gene. Thus, this study aimed to investigate molecular epidemiology and colistin-resistant mechanism of mcr -positive and mcr -negative Escherichia coli isolates from animal in Sichuan Province, China. In this study, a total of 101 colistin-resistant E. coli strains were isolated from 300 fecal samples in six farms in Sichuan Province. PCR was used to detect mcr gene (mcr-1 to mcr-9). The prevalence of mcr-1 in colistin-resistant E. coli was 53.47% (54/101), and the prevalence of mcr-3 in colistin-resistant E. coli was 10.89% (11/101). The colistin-resistant E. coli and mcr-1 –positive E. coli showed extensive antimicrobial resistance profiles. For follow-up experiments, we used 30 mcr -negative and 30 mcr-1 –positive colistin-resistant E. coli isolates and E. coli K-12 MG1655 model strain. Multi-locus sequence typing (MLST) of 30 strains carrying mcr-1 as detected by PCR identified revealed six strains (20%) of ST10 and three strains (10%) of each ST206, ST48, and ST155 and either two (for ST542 and 2539) or just one for all other types. The conjugation experiment and plasmid replicon type analysis suggest that mcr-1 was more likely to be horizontally transferred and primarily localized on IncX4-type and IncI2-type plasmid. The ST diversity of the mcr-1 indicated a scattered and non-clonal spreading in mcr-1 –positive E. coli. Twenty-eight mcr -negative colistin-resistant E. coli isolates carried diverse amino acid alterations in PmrA, PmrB, PhoP, PhoQ, and MgrB, whereas no mutation was found in the remaining isolates. The finding showed the high prevalence of colistin resistance in livestock farm environments in Sichuan Province, China. Our study demonstrates that colistin resistance is related to chromosomal point mutations including the two-component systems PhoP/PhoQ, PmrA/PmrB, and their regulators MgrB. These point mutations may confer colistin resistance in mcr -negative E. coli. These findings help in gaining insight of chromosomal-encoded colistin resistance in E. coli. [ABSTRACT FROM AUTHOR]

The emergence of the plasmid-mediated colistin resistance gene mcr-1 is threatening the last-line role of colistin in human medicine. With mcr-1 -positive Escherichia coli (E. coli) isolated from food animal being frequently reported in China, the prevalence of mcr-1 in food animal has attracted public attention. In the present study, a total of 105 colistin-resistant E. coli strains were isolated from 200 fecal samples collected from six swine farms in northeastern China. mcr -PCR revealed that the prevalence of mcr-1 in colistin-resistant E. coli was 53.33% (56/105). mcr-1 -positive E. coli showed extensive antimicrobial resistance profiles with the presence of additional resistance genes, increased expression of multidrug efflux pump-associated genes, and increased biofilm formation ability. MLST differentiated all the mcr-1- positive E. coli into 25 sequence types (STs) and five unknown ST, and the most common ST was ST10 (n = 11). By phylogenetic group classification, the distribution of all mcr-1 -positive E. coli belonging to groups A, B1, B2, and D was 46.43, 35.71, 5.36, and 5.36%, respectively. Conjugation experiment demonstrated that most of the mcr-1 were transferable at frequencies of 2.68 × 10–6–3.73 × 10–3 among 30 representative mcr - 1- positive E. coli. The plasmid replicon types IncI2 (n = 9), IncX4 (n = 5), IncHI2 (n = 3), IncN (n = 3), and IncP (n = 1) were detected in the transconjugants. The results of growth assay, competition experiment, and plasmid stability testing showed that acquisition of mcr-1- harboring plasmids could reduce the fitness of bacterial hosts, but mcr-1 remained stable in the recipient strain. Due to the potential possibility of these mcr-1 -positive E. coli being transmitted to humans through the food chain or through horizontal transmission, therefore, it is necessary to continuously monitor the prevalence and dissemination of mcr-1 in food animal, particularly in swine. [ABSTRACT FROM AUTHOR]

Background: It has been demonstrated that swine waste is an important reservoir for resistant genes. Moreover, the bacteria carrying resistant genes and originating from swine feces and wastewater could spread to the external environment. Fluoroquinolones (FQs) are widely used in livestock and poultry for the treatment of bacterial infection. However, resistance to FQs has increased markedly. Results: In this study, swine feces and wastewater were sampled from 21 swine farms of seven provinces in China to investigate the prevalence of FQ resistance, including plasmid-mediated fluoroquinolone resistance (PMQR) genes and the occurrence of target mutations. All isolates showed moderate rate of resistance to norfloxacin (43.0%), ciprofloxacin (47.6%), ofloxacin (47.0%) and levofloxacin (38.8%). The percentage of strains resistant to the four FQs antimicrobials was positively correlated with the danofloxacin (DANO) MIC. Among the 74 FQ-resistant isolates, 39 (52.70%) had mutations in gyrA (S83L and D87 to N, Y, G, or H), 21 (28.38%) had mutations in parC (S80I and E84K), 2 (2.70%) had mutations in parE (I355T and L416F), 26 (35.14%) had mutations in marR (D67N and G103S), 1 (1.35%) had mutations in acrR (V29G). While, no mutation was found in gyrB. There were 7 (9.46%) strains carried the qnrS gene, 29 (39.19%) strains carried the oqxAB gene, and 9 (12.16%) strains carried the aac (6′)-Ib-cr gene. In addition, the conjugation assays showed that qnrS, oqxAB and aac (6′)-Ib-cr could be successfully transferred to E. coli J53 from 4 (57.1%), 20 (69.0%) and 5 (55.6%) donor strains, respectively. There were no qnrA, qnrB, qnrC, qnrD and qepA genes detected. Conclusion: The present study showed that DANO-resistant E. coli strains isolated from swine farms had significant cross-resistance to other four FQs antimicrobials. Further study revealed that the resistance mechanisms of swine-derived E. coli to FQs may be attributable to the occurrence of chromosomal mutations (gyrA, parC, parE, marR and acrR genes double-site or single-site mutation) and the presence of PMQR genes (qnrS, oqxAB and aac (6′)-Ib-cr). To the best of our knowledge, one novel mutation marR-D67N was found to be associated with FQ resistance, two mutations parE-L416F and acrR-V29G have never been reported in China. [ABSTRACT FROM AUTHOR]

Colla corii asini (CCA) is a widely used animal-derived traditional medicine and nutritional supplement in China that has a variety of bioactive effects, especially anti-anaemic effects. To date, the effective substances in CCA are still unclear, thus limiting the evaluation of the quality and consistency of CCA. In this study, a microcalorimetry-based bioassay method was established to assess the quality of CCA by investigating its effects on the growth and metabolism of Escherichia coli, and ten biothermodynamic parameters were employed to characterize the biothermal changes. A principal component analysis (PCA) of these parameters showed that CCA significantly promotes the heat production of E. coli compared to that in the control group, and CCA showed an obvious dose–effect relationship from 0.625 to 20 mg mL−1. Then, the effects of 12 batches of CCA from three different manufacturers were studied at a concentration of 5 mg mL−1, which had a good effect and showed good intraday and daytime reproducibility. The results revealed distinctive characteristics among different manufacturers and good consistency within the same manufacturer according to the scores of the first principal component. In summary, the method based on microcalorimetric has good prospects in the evaluation of the quality of CCA. [ABSTRACT FROM AUTHOR]

China has a high agricultural output and is a significant carbon emitter; thus, reducing carbon emissions in the agricultural sector is crucial for achieving carbon neutrality. To address this, China implemented the National Agricultural Sustainable Development Experimental Demonstration Zone policy in 2018, in which reducing agricultural carbon emissions (ACE) is a subject of concern. We explore the impact of the policy on agricultural carbon emissions reduction (ACER) using the propensity score matching and differences-in-differences (PSM-DID) methods with a series of robustness tests based on the panel data of prefecture-level cities in China from 2011 to 2020. The results indicate that: (1) the policy significantly reduces carbon emissions and impacts carbon emission sources, with the results passing the robustness tests. (2) According to the mechanism test, agricultural financial support mediates carbon emissions reduction, and the policy reduces these emissions by decreasing the intensity of fiscal support. (3) The heterogeneity analysis illustrates that the carbon emissions reduction effect is more evident in cities with a small urban-rural income gap and a high proportion of agricultural output value. Finally, we provide suggestions to reduce carbon emissions from the perspective of national and local governments. This paper is particularly relevant for achieving sustainable agriculture development. [ABSTRACT FROM AUTHOR]

We explored the relationship between moderate to vigorous physical activity (MVPA), cell phone screen time (CPST) and cell phone dependence with 715 children at primary schools in China. The students completed the Children's Leisure Activities Study Survey-Chinese edition, the Mobile Phone Usage Frequency Scale, and the Self-Assessment Questionnaire on Adolescent Mobile Phone Use Dependence. The results showed that there was a significant negative correlation between the children's mean daily MVPA time and cell phone dependence, cravings, and physical and mental effects; those children who did not meet the World Health Organization's recommended MVPA levels had stronger cravings for cell phones. In addition, there was a low to moderate positive correlation between CPST and cell phone dependence. It is recommended that primary school students participate in more MVPA and reduce their CPST to reduce the cravings for cell phones and the negative physical and mental effects of cell phone use. [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: As a traditional Chinese medicine, seed of Platycladus orientalis(Linnaeus) Franco has been extensively used as a tonic and sedative remedy. The present study was conducted to investigate whether lifespan was extended and the mechanisms of n-butanol extract from seed of Platycladus orientalis (BSPO) in Caenorhabditis elegans. The findings could provide the pharmacological basis for a treatment in traditional medicine. Materials and methods: Lifespan extension by BSPO was evaluated under normal culture conditions and in a stress test. A possible mechanism of the anti-aging effect of BSPO, a change in the stress-resistance of related proteins, was also investigated in C. elegans. Results: It has been shown that BSPO could significantly extend lifespan of C. elegans in a concentration dependent manner under normal culture conditions and stress. Further studies demonstrated that BSPO treatment significantly decreased reactive oxygen species (ROS) accumulation, up-regulated resistance to stress of related proteins, including glutathione S-transferase-4 (GST-4) and heat shock protein-16.2 (HSP-16.2), and reduced the amount of lipofuscin in transgenic C. elegans. Conclusion: These results indicated that BSPO extended the lifespan, which could be attributed to its direct ROS scavenging activity, reducing the amount of lipofuscin and increasing the expression of gens associated with resistance to stress. These obtained data provided valuable support for traditional clinical practice to extend lifespan and to provide tonic remedy. [Copyright &y& Elsevier]

China is the largest coal producer and the largest coal consuming country in the world. Approximately half of China's coal comes from small-scale mines. The sustainability of China's coal industry would be improved if a greater share of the coal come from larger-scale mines. This article presents a case history of the Shuangliu Mine in Shanxi Province and discusses the issues and benefits of the transformation of this mine. Significant gains were observed in worker safety and benefits, and in more efficient exploitation of the coal resource. Problems included loss of employment opportunities for local labourers, and reduced revenue for local townships. The wider implications of a shift of China's coal supply from small-scale to large-scale mining operations are discussed in relation to economic, social and environmental aspects. [ABSTRACT FROM AUTHOR]

Tao, S.; Liu, H.B.; Wang, S.T., and Li, C.H., 2020. Construction of smart coastal cities based on digital government. In: Al-Tarawneh, O. and Megahed, A. (eds.), Recent Developments of Port, Marine, and Ocean Engineering. Journal of Coastal Research, Special Issue No. 110, pp. 154–158. Coconut Creek (Florida), ISSN 0749-0208. With the development of China's economy and society, the progress of urbanization has accelerated, and a series of issues such as population, transportation, and environment problems have emerged in the process of the operation and development of the cities. The concept of smart city has pointed out the direction to solve the above problems, and governments at all levels have been actively promoting the construction and development of digital cities. Based on literature review and empirical analysis, this paper takes a coastal city X of Fujian Province, China as an example to study the smart city construction process in coastal areas, it analyzes the existing problems and proposes corresponding feasible countermeasures. The research results show that digital government can promote the construction progress of smart coastal cities through top-level design and data sharing; aiming at problems such as insufficient information infrastructure and imperfect development environment, the government should guide investment to participate in the construction, innovatively develop the "Internet+" industry, and strive to create an upgraded version of smart city, the Smart Coast. This study has certain reference significance for the construction and development of smart coastal cities, and provides an effective way for the government to plan, construct and manage the digital cities. [ABSTRACT FROM AUTHOR]

As a health-care food and traditional Chinese medicine, E'jiao, from the skin of Equus animus L, has been used to nourish blood in China for more than 2000 years. In modern medicine, there are also evidences indicate it has a beneficial effect on chemotherapy-caused blood deficiency. However, its mechanism of action for blood invigoration remains unclear. In the present study, we investigated the hematopoietic effect of E'jiao in 5-Fluorouracil-treated mice. In addition to the counting of bone marrow nucleated cells (BMNCs), flow cytometry was used to detect the population of hematopoietic stem cells (HSCs), and colony-forming unit (CFU) was used to assay the differentiation ability of hematopoietic progenitor cells (HPCs). Gene expression profiles of bone marrow cells were obtained from RNA sequencing (RNA-seq) and differentially expressed genes (DEGs) were analyzed with an emphasis on hematopoiesis-related pathways. The results show that E'jiao promotes the proliferation of both BMNCs and HSCs, as well as the differentiation of HPCs. By providing a hematopoiesis-related molecular regulatory network of E'jiao, we point out that the mechanism of E'jiao is associated with pathways including ECM-receptor interaction, Wnt signaling pathway, PI3K-Akt signaling pathway, TGF-beta signaling pathway, Hematopoietic cell lineage and Osteoclast differentiation, in which Ibsp, Col1a1, Col1a2, Notum, Sost, Dkk1, Irx5, Irx3 and Dcn are the key regulatory molecules. These findings provide valuable molecular basis for the mechanism of action of E'jiao. [ABSTRACT FROM AUTHOR]

Objectives: Despite remarkable advances in the treatment of oesophageal cancer (OC), the role of antiepidermal growth factor receptor (anti-EGFR) agents in treating OC remains controversial. Herein, a systematic review and meta-analysis were conducted to elucidate the efficacy and safety of anti-EGFR agents in patients with OC., Design: Meta-analysis of randomised controlled trials (RCTs) identified by searching the PubMed, Embase, Web of Science, ClinicalTrials.gov, Cochrane Library, Chinese Biology Medicine, China National Knowledge Infrastructure and Wanfang Data Knowledge Service Platform databases from inception to December 2019. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines., Setting: RCTs from any country and healthcare setting., Participants: Patients with OC., Interventions: Combination therapy with anti-EGFR agents and conventional treatments versus conventional treatments alone in patients with OC., Primary and Secondary Outcome Measures: Overall survival (OS) and progression-free survival (PFS) were primary outcome measures, and objective response rate (ORR), disease control rate (DCR) and treatment toxicities were secondary outcome measures., Results: In total, 25 RCTs comprising 3406 patients with OC were included. Overall, anti-EGFR treatment significantly improved the OS (HR: 0.81, 95% CI 0.74 to 0.89, p<0.00001), ORR (relative risk (RR): 1.33, 95% CI 1.16 to 1.52, p<0.0001) and DCR (RR: 1.22, 95% CI 1.11 to 1.34, p<0.0001) but not PFS (HR: 0.91, 95% CI 0.76 to 1.08, p=0.26). Anti-EGFR treatment was significantly associated with higher incidences of myelosuppression, diarrhoea, acne-like rash and hypomagnesaemia., Conclusions: Overall, anti-EGFR agents have positive effects on OS, the ORR and DCR in OC. However, considering the high incidence of adverse effects, such as myelosuppression, diarrhoea, acne-like rashes and hypomagnesaemia, careful monitoring of patients with OC is recommended during anti-EGFR treatment., Trial Registration Number: CRD42020169230., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Abstract: The emergence and global distribution of the mcr-1 gene for colistin resistance have become a public concern because of threats to the role of colistin as the last line of defense against some bacteria. Because of the prevalence of mcr-1-positive Escherichia coli isolates in food animals, production of these animals has been regarded as one of the major sources of amplification and spread of mcr-1. In this study, 249 E. coli isolates were recovered from 300 fecal samples collected from swine farms in Heilongjiang Province, People's Republic of China. Susceptibility testing revealed that 186 (74.70%) of these isolates were colistin resistant, and 86 were positive for mcr-1. The mcr-1-positive isolates had extensive antimicrobial resistance profiles and additional resistance genes, including blaTEM, blaCTX-M, aac3-IV, tet(A), floR, sul1, sul2, sul3, and oqxAB. No mutations in genes pmrAB and mgrB were associated with colistin resistance. Phylogenetic group analysis revealed that the mcr-1-positive E. coli isolates belonged to groups A (52.33% of isolates), B1 (33.72%), B2 (5.81%), and D (8.14%). The prevalence of the virulence-associated genes iutA, iroN, fimH, vat, ompA, and traT was moderate. Seven mcr-1-positive isolates were identified as extraintestinal pathogenic. Among 20 mcr-1-positive E. coli isolates, multilocus sequence typing revealed that sequence type 10 was the most common (five isolates). The conjugation assays revealed that the majority of mcr-1 genes were transferable at frequencies of 7.05 × 10-7 to 7.57 × 10-4. The results of this study indicate the need for monitoring and minimizing the further dissemination of mcr-1 among E. coli isolates in food animals, particularly swine., (Copyright ©, International Association for Food Protection.)

Background: Previous studies on the effects of lipotoxicity and oxidative stress on islet beta cell function mainly focused on patients with diabetes, whereas studies on normal glucose tolerance (NGT) are few. The aim of this study was to explore the relationships among triglyceride (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), oxidative stress indicators, insulin resistance, and beta cell function in populations with different glucose and lipid metabolism states., Methods: A total of 517 individuals were recruited from a rural community in Beijing, China. Glucose metabolism status was defined according to the results of a 75-g oral glucose tolerance test (OGTT). Dyslipidemia was defined as abnormal TG, HDL-c, or LDL-c levels. The population was divided into four groups: individuals with normal glucose and lipid levels (group A, n = 62); those with dyslipidemia alone (group B, n = 82); those with dysglycemia alone (group C, n = 121); and those with dysglycemia and dyslipidemia (group D, n = 247). Oxidative stress indicators, including superoxide dismutase (SOD), glutathione reductase (GR) and 8-hydroxydeoxyguanosine (8-OHdG), were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) and glucose disposition index (DI 30 , DI 120 ) were calculated to assess insulin resistance and islet beta cell function, respectively. Stratified multiple linear regression analysis was used to explore relationships between TG, HDL-c, LDL-c, oxidative stress indicators, and insulin resistance (natural log transformation of HOMA-IR, LnHOMA-IR) and beta cell function (natural log transformation of DI 30 , Ln DI 30 )., Results: Compared with the control group, populations with dyslipidemia and/or dysglycemia showed significantly increased insulin resistance. Dyslipidemia aggravated insulin resistance and beta cell dysfunction in individuals with dysglycemia. Stratified regression analysis showed that TG positively correlated with LnHOMA-IR in individuals with normal glucose levels (beta = 0.321, 0.327, P = 0.011, 0.003 in groups A and B, respectively) and negatively correlated with LnDI 30 in participants with dyslipidemia (beta = - 0.225, - 0.122, P = 0.035, 0.048 in groups B and D, respectively). Reduced serum SOD levels in individuals with dysglycemia plus dyslipidemia were observed, and a negative association between TG and SOD levels was found (r = - 0.461, P < 0.001)., Conclusion: TG correlated with both insulin resistance and beta cell function in individuals with dyslipidemia alone. SOD negatively correlated with TG, indicating a close relationship between oxidative stress and glucose-lipid metabolism. Due to the adverse effect of hypertriglyceridemia on insulin sensitivity and islet beta cell function, more attention should be paid to the detection and management of hypertriglyceridemia.

The enzyme activities of the fungus Lasiodiplodia theobromae (L. theobromae) were studied during degradation of benzo[a]pyrene (BaP). The L. theobromae was isolated from a polycyclic aromatic hydrocarbons (PAHs) contaminated soil collected from the Beijing Coking Plant in China and can potentially use BaP as its sole carbon source with a degradation ratio of up to 53% over 10 days. The activities of lignin peroxidase (LiP) and laccase (LAC) could be detected during BaP biodegradation; while manganese peroxidase (MnP) was not detected. Both glucose and salicylic acid enhanced BaP biodegradation slightly. In contrast, the coexistence of phenanthrene (PHE) inhibited BaP degradation. These metabolic substrates all enhanced the secretion of LiP and LAC. The addition of Tween 80 (TW-80) enhanced BaP biodegradation as well as the LiP and LAC activities. At the same time, TW-80 was degraded by the L. theobromae. In addition, the L. theobromae was compared to Phanerochaete chrysosporium (P. chrysosporium), which is a widely studied fungus for degrading PAH. P. chrysosporium was unable to use BaP as its sole carbon source. The activities of LiP and LAC produced by the P. chrysosporium were less than those of the L. theobromae. Additionally, the four intermediates formed in the BaP biodegradation process were monitored using GC-MS analysis. Four metabolite concentrations first increased and then decreased or obtained the platform with prolonged BaP biodegradation time. Therefore, this study shows that the L. theobromae may be explored as a new strain for removing PAHs from the environment.

Benzo[a]pyrene (BaP), a five-ring polycyclic aromatic hydrocarbon (PAH), which has carcinogenic potency, is highly recalcitrant and resistant to microbial degradation. A novel fungus, Lasiodiplodia theobromae (L. theobromae), which can degrade BaP as a sole carbon source in liquid, was isolated in our laboratory. To prompt the further application of L. theobromae in remediation of sites polluted by BaP and other PAHs, the present study was targeted toward the removal of BaP and PAHs from soil by L. theobromae. The degradation of BaP by L. theobromae was studied using a soil spiked with 50 mg/kg BaP. L. theobromae could remove 32.1 % of the BaP after 35 days of cultivation. Phenanthrene (PHE) inhibited BaP degradation as a competitive substrate. The tested surfactants enhanced BaP degradation in soil by different extents, and a removal rate of 92.1 % was achieved at a Tween-80 (TW-80) concentration of 5 g/kg. It was revealed that TW-80 could not only enhance BaP bioavailability by increasing its aqueous solubility and decreasing the size of its colloid particles but also increase enzyme secretion from L. theobromae and the population of L. theobromae. Moreover, ergosterol content together with the biomass C indicated the increase in L. theobromae biomass during the BaP biodegradation process in soils. Finally, a soil from a historically PAH-contaminated field at Beijing Coking Plant in China was tested to assess the feasibility of applying L. theobromae in the remediation of polluted sites. The total removal rate of PAHs by L. theobromae was 53.3 %, which is 13.1 % higher than that by Phanerochaete chrysosporium (P. chrysosporium), an effective PAH degrader. The addition of TW-80 to the field soil further enhanced PAH degradation to 73.2 %. Hence, L. theobromae is a promising novel strain to be implemented in the remediation of soil polluted by PAHs.

Objective: To find out the vitamin A intake in middle-aged and aged females, and to investigate the relationship between retinol intake and bone mineral density (BMD)., Methods: Two hundred and fifty women aged 45 to 66 were enrolled and received physical examination and BMD scanning, and their fasting blood samples and dietary records were collected. Serum retinol and beta-carotene were analyzed by HPLC. Assays for bone turnover markers (such as bone specific alkaline phosphatase, osteocalcin and 25-(OH) D3) in serum were performed by using commercially available kits. Subjects were divided into normal BMD group and low BMD group, and the dietary RE intakes and serum retinol were compared., Results: The average RE intake was 455.8 microg (n = 169), which reached 65.1% of RNI. Serum retinol and beta-carotene in normal BMD group were a little bit higher than the low BMD group, but there was no statistic difference. Vitamin A intake of normal BMD group was 53.0 microg, which was lower than the low BMD group, and carotene intake of normal BMD group was 107.6 microg, which was higher than the low BMD group. The ratio of plant sourced retinol in normal BMD group was higher than the low BMD group. Bivariate correlation analysis on BMD and dietary RE intake showed no statistic correlation, but with a slight negative trend (P = 0.203, r = -0.140). There was a significantly difference in age, bone mineral contents, BMI and BSAP between low BMD group and normal BMD group (P < 0.001 or P < 0.01), and bivariate correlation analysis showed that the age (P < 0.001, r = -0.380), BMI (P < 0.001, r = 0.394) menopausal age (P < 0.05, r = 0.244) and body weight (P < 0.001, r = 0.434) were significantly correlated with BMD. The result of stepwise linear regression analysis showed that the age, menopausal years and BSAP were entered into the regression equation (R2 = 0.552, F = 24.661, P < 0.001), which indicated a strong connection with BMD., Conclusion: (a) RE intake did not reach RNI, and the use of supplements was not common (32.5%). (b) The intake of milk and milk products and beans and bean products was low, and the calcium intake did not reach 50% of AI. (c) Higher serum retinol in normal range might maintain BMD. (d) Too much RE intake might associate with decreased BMD, especially the BMD in femoral bone.