Search

Microplastics can act as carriers of heavy metals and may enter humans through ingestion and threaten human health. However, the bioaccessibility of heavy metals associated with microplastics and its implications for human health risk assessments are poorly understood. Therefore, in this study, four typical heavy metals (As(V), Cr(VI), Cd(II), and Pb(II)) and one typical microplastic (polyvinyl chloride, PVC) were chosen to estimate the human health risk of microplastic-associated heavy metals by incorporating bioaccessibility. Significant adsorption of heavy metals was observed with the following order for adsorption capacity: Pb(II) Cr(VI) Cd(II) As(V); the efficiencies for desorption of these four heavy metals from PVC microplastics were all below 10%. The Fourier transform infrared spectroscopy results indicated that the functional groups on the surface of the virgin PVC microplastics did not play an important role in the capture process. Heavy metals in both gastric and small intestinal phases were prone to release from PVC microplastics when bioaccessibility was evaluated with the in vitro SBRC (Soluble Bioavailability Research Consortium) digestion model. In addition, Pb(II) bioaccessibility in the gastric phase was significantly higher than those in the other phases, while As(V), Cr(VI), and Cd(II) bioaccessibilities showed the opposite trend. After incorporating bioaccessibility adjustments, the noncarcinogenic hazards and carcinogenic risks determined were lower than those based on total metal contents. The individual hazard quotients (HQ) and carcinogenic risks (CR) for ingestion of these four heavy metals from PVC microplastics were all lower than the threshold values for adults and children. In summary, this study will provide a new view of the human health risks of heavy metals associated with microplastics.

Background The impact of labor epidural analgesia (LEA) on breastfeeding remains controversial. The aim of this study was to assess the relationship between LEA use and exclusive breastfeeding (EBF) up to 6 months. Methods This was a cross-sectional survey on healthy mothers who had vaginal delivery with infants aged 7-12 months from seven maternal health WeChat groups in Jiaxing, China. Data including EBF status up to 6 months, maternal sociodemographic characteristics, LEA use in labor, breastfeeding supports during hospitalization and reasons for stopping EBF were collected using online self-administered questionnaires in October 2021. A multivariable logistic regression model was used to determine the potential association of LEA use with EBF up to 6 months by the adjusted odds ratio (AOR) and 95% confidence interval (CI). Results Of a total of 537 surveyed mothers, 408 (76.0%) delivered with LEA and 398 (74.1%) exclusively breastfed their infants until 6 months. All mothers delivered in the hospitals with active breastfeeding policies. There was no statistical difference in the rate of EBF up to 6 months between mothers with and without LEA (73.8% versus 75.2%, P = 0.748). Multivariable logistic regression analysis indicated that only increased maternal age (AOR = 0.906, 95% CI 0.854-0.961, P = 0.001) and perceived insufficient breast milk (AOR = 0.129, 95% CI 0.082-0.204, P Conclusions LEA does not affect EBF up to 6 months. Other factors such as health education and breastfeeding-friendly hospital strategies may be much more important to breastfeeding outcomes compared to LEA use.

The large-scale Qixiashan Pb-Zn Deposit in the eastern Middle-Lower Yangtze metallogenic belt is hosted in carbonate rocks. Based on a detailed mineral paragenesis study, in-situ LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometer) trace element geochemistry data for pyrite and sphalerite from different stages in the Qixiashan Deposit are reported, the Pb-Zn mineralization processes are reconstructed, and a genetic model is constructed. Four paragenetic stages of Pb-Zn ore deposition are identified: the biogenic pyrite mineralization stage (Stage 1), the early stage of hydrothermal Pb-Zn mineralization (Stage 2), the late stage of hydrothermal Pb-Zn mineralization (Stage 3), and the carbonate stage (Stage 4). Stages 2 and 3 are the main ore stages. The trace element characteristics of the sulfide in stages 2 and 3, such as the higher Co/Ni and lower trace element contents of the pyrite and the Fe, Mn, and Ge contents of the sphalerite, indicate that they were generated by magmatic-hydrothermal processes. Furthermore, the lower Cu, Ag, Sb, and Pb contents of the pyrite and sphalerite of Stage 3 compared to Stage 2 suggest an increase in magmatic-hydrothermal activity from Stage 2 to Stage 3. The hydrothermal fluids leached trace elements (e.g., Cu, Ag, Sb, and Pb) from the previously deposited primary pyrite and sphalerite, which were precipitated in the later hydrothermal stage Cu, Au, Ag, Sb, and Pb bearing minerals and secondary pyrite and sphalerite with lower trace element contents (e.g., Cu, Au, Ag, Sb, and Pb). Compared with the pyrite from stages 2 and 3, the Stage 1 pyrite has relatively higher trace elements contents (Sb, Cu, Zn, Au, Ag, Pb, As, and Ni). However, their lower Co/Ni ratio suggests a syngenetic sedimentary origin. Based on the petrographic features and trace element data, a multi-stage mineralization model is proposed. The Stage 1 biogenic pyrite formed stratiform pyrite layers, which provided reducing conditions and a base for the subsequent Pb-Zn mineralization. During Stage 2, subsequent hydrothermal fluid interacted with the stratiform pyrite layers, which resulted in sulfide precipitation and the formation of stratiform Pb-Zn orebodies. In Stage 3, the hydrothermal fluid replaced the limestone along the fractures, which triggered the formation of Pb-Zn vein orebodies.

By using a nanosized tetracarboxylate ligand 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine (H4TCPP) as a building block, the synthesis of a new microporous Co-based metal–organic framework was performed by making Co(NO2)3·6H2O and the presence of bpy ligand to react under solvothermal reaction, and its chemical formula is [Co3(OH)2(H2TCPP)2(bpy)](DMF)3 (1, bpy = 4,4ʹ-bipyridine). Gas adsorption studies reveal that the mixtures of C2H2/CH4 and C2H2/CO2 could be selectively separated by the obtained activated 1a. The protective effect of compound on AGN was further evaluated in vitro. The RT-PCR was carried out to determine the relative expression of tnf-α, nf-κb in glomerular cells after bacterial infection and compound treatment. The IL-1β and IL-18 content in glomerular cells was also evaluated by ELISA after compound treatment. Finally, the results obtained through molecular docking exhibited possible regulation mechanism on regulation of binding affinity between DNA and target protein.

There is yet no consensus on the application of functional imaging and qualitative image interpretation in the management of gastric cancer. In this second part, we will discuss the role of image-derived quantitative parameters from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in gastric cancer, as both techniques have been shown to be promising and useful tools in the clinical decision making of this disease. We will focus on different aspects including aggressiveness assessment, staging and Lauren type discrimination, prognosis prediction and response evaluation. Although both the number of articles and the patients enrolled in the studies were rather small, there is evidence that quantitative parameters from DCE-MRI such as Ktrans, Ve, Kep and AUC could be promising image-derived surrogate parameters for the management of gastric cancer. Data from 18F-FDG PET/CT studies showed that standardised uptake value (SUV) is significantly associated with the aggressiveness, treatment response and prognosis of this disease. Along with the results from diffusion-weighted MRI and contrast-enhanced multidetector computed tomography presented in Part 1 of this critical review, there are additional image-derived quantitative parameters from DCE-MRI and 18F-FDG PET/CT that hold promise as effective tools in the diagnostic pathway of gastric cancer. KEY POINTS: • Quantitative analysis from DCE-MRI and18F-FDG PET/CT allows the extrapolation of multiple image-derived parameters. • Data from DCE-MRI (Ktrans, Ve, Kep and AUC) and 18F-FDG PET/CT (SUV) are non-invasive, quantitative image-derived parameters that hold promise in the evaluation of the aggressiveness, treatment response and prognosis of gastric cancer.

Two new diketopiperazines (1, 2), one new polyprenol (3), together with 19 known compounds (4-22) were obtained from the EtOAc extract of Bionectria sp. Y1085, an endophytic fungus isolated from the plant Huperzia serrata. Their structures were elucidated by extensive NMR and MS analysis. Bionectin D (1) is a rare diketopiperazine with a single methylthio substitution at the α-carbon of cyclized amino acid residue. The antibacterial activity of compounds was assayed against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium ATCC 6539, and some metabolites (1, 2, 10, 11, and 14) exhibited evident antibacterial activity.

This paper researches constructive generalized synchronization (GS) for bidirectional continuous array of differential systems (BCADS). The results give general representations of GS in BCADS. The effectiveness of the theoretical results has been shown according numerical simulations.

Background Rapid demographic and economic changes have made chronic disease the number one health issue in China, contributing to more than 80% of the country’s 10.3 million annual deaths and nearly 70% of its total disease burden (Wang et al., Toward a Healthy and Harmonious Life in China: Stemming the Rising Tide of Non-Communicable Diseases, 2011; Yip and Hsiao, Lancet 384: 805-18, 2014). Diabetes is a major contributor to the chronic disease burden and is experienced by nearly 11% of the adult population of China (Yang et al., N Engl J Med 362:1090-101, 2010). In response to the challenges of chronic disease, the Chinese government initiated comprehensive health care reforms nationwide in 2009. A key measure was a hierarchical diagnosis and treatment system for monitoring and reducing chronic diseases and improving the community health service system (Barber et al., Health Policy Plan 29:367-78, 2014). Primary hospitals, such as community health service centers, are the main gatekeepers for management of diabetes and other chronic diseasesin China. In recognition of the need for a more patient-centered approach, the Chinese government has piloted a program incorporating methods of diabetes self-management for chronic care: the Happy Life Club (Browning et al., Front in Public Health 2:181, 2015). This program is modeled on a similar program developed in Australia (Kelly et al., Aust J Prim Health 9:186-9, 2003). The ICDMS is an important tool in the implementation of patient-centered programs targeting chronic health issues, and its success is determined by factors, such as frequent contact between patients and doctors and effective website training for patients. This retrospective study used de-identified data from the Fangzhuang (Beijing) intelligent chronic disease management system (ICDMS) database to evaluate the effect of an intelligent chronic disease management system on selected Beijing community patients who have type 2 diabetes mellitus (T2DM). Methods A comparative study before and after ICDMS implementation was performed to evaluate the effect of ICDMS on the rates of follow-up and laboratory examinations, measurement rates of blood glucose and lipids, glycosylated hemoglobin (HbA1c) and blood lipid levels, as well as the corresponding health parameters. Continuous variables and categorical variables were analyzed using paired t-test and McNemar’s tests, respectively. Results A total of 2451 T2DM patients met inclusion/exclusion criteria. Compared with the pre-index period, the laboratory examination, rates of blood glucose and blood lipids increased significantly in the post-index period (p

We propose a new method for inverting source function of microseismic event induced in mining. The observed data from microseismic monitoring during mining are represented by a wave equation in a spherical coordinate system and then the data are transformed from the time-space domain to the time-slowness domain based on tomographic principle, from whichwe can obtain the signals related to the source in the time-slowness domain. Through analyzing the relationship between the signal located at the maximum energy and the source function, we derive the tomographic equations to compute the source function from the signals and to calculate the effective radiated energy based on the source function. Moreover, we fit the real amplitude spectrum of the source function computed from the observed data into the ω−2 model based on the least squares principle and determine the zero-frequency level spectrum and the corner frequency, finally, the source rupture radius of the event is calculated and The synthetic and field examples demonstrate that the proposed tomographic inversion methods are reliable and efficient

The effect of sodium nitroprusside (SNP; nitric oxide donor) treatment on wheat plant (Triticum aestivum L.) under drought stress during grain filling stage was investigated. When two cultivars wheat plants, Yumai No. 949 and Shanmai No. 5, were drought stressed by PEG for 72 h and rewatered for 48 h, the affections of osmotic dehydration and rehydration on the antioxidant enzymes activities and psbA gene transcriptional abundance were compared. Relative water contents (RWC) decreased markedly after 72 h of PEG stress, along with an obvious decrease in chlorophyll content, increase in SOD, CAT and APX activities, and MDA content as well. Real-time quantitative polymerase chain amplification indicated that drought stress also remarkably inhibited the transcription of psbA gene in photosystem II (PSII). All of these responses could be restored by removing of stress and applying another 48 h of rewatering. The exogenous 0.2 mmol l−1 SNP treatment could significantly alleviate the stress injury and accelerate the progress of recovery. Compared to Yumai No. 949, Shanmai No. 5 had less destroyed plasma membranes, higher RWC and chlorophyll contents, more psbA gene transcriptional abundance during water stress, and rapider recovery to control after rewatering, suggesting not only a better drought resistance but also a better recovery capability after a severe drought stress. The present results also suggested that the application of exogenous SNP could enhance the stress resistance of wheat plant during grain filling stage by increasing antioxidant enzymes activities, as well as protecting important gene transcription in PSII, which were to the benefit of functional recovery from drought stress.

Frequency domain wave equation forward modeling is a problem of solving large scale linear sparse systems which is often subject to the limits of computational efficiency and memory storage. Conventional Gaussian elimination cannot resolve the parallel computation of huge data. Therefore, we use the Gaussian elimination with static pivoting (GESP) method for sparse matrix decomposition and multi-source finite-difference modeling. The GESP method does not only improve the computational efficiency but also benefit the distributed parallel computation of matrix decomposition within a single frequency point. We test the proposed method using the classic Marmousi model. Both the single-frequency wave field and time domain seismic section show that the proposed method improves the simulation accuracy and computational efficiency and saves and makes full use of memory. This method can lay the basis for waveform inversion.

The stability of a class of delayed cellular neural networks (DCNN) with or without noise perturbation is studied. After presenting a simple and easily checkable condition for the global exponential stability of a deterministic system, we further investigate the case with noise perturbation. When DCNN is perturbed by external noise, the system is globally stable. An important fact is that, when the system is perturbed by internal noise, it is globally exponentially stable only if the total noise strength is within a certain bound. This is significant since the stochastic resonance phenomena have been found to exist in many nonlinear systems.

In recent years, Agaricus mushroom production has undergone an important increase in the world. However, there is no consensus over the taxonomy of some commercial strains. So rapid and reliable methods to identify Agaricus strains are urgently needed. In this paper, six inter-simple sequence repeat (ISSR) primers were screened from 20 primers to analyse the genetic diversities of the 12 main commercial strains of Agaricus in China. The results showed that a total of 124 bands were produced, among which 80.6% was polymorphic, the similarity coefficients ranged from 0.69 to 0.98. Twelve tested strains were divided into 2 groups on the similarity coefficient of 0.75. Three Agaricusbitorquis strains were clustered in one group, and seven Agaricus bisporus strains were clustered with Agaricus strains S1 and S2 in the other group. As comparison with ISSR, intergenic spacers combined with restriction fragment length polymorphisms (IGS-RFLP) was employed to analyse genetic diversities of the tested strains by digesting IGS amplified products with restriction enzymes Hae III, Alu I, Rsa I, respectively, and IGS-RFLP cluster results were similar with those of ISSR. However, ISSR was superior to IGS-RFLP in differentiating closely related strains. It is suggested that the ISSR marker is an alternative method to differentiate Agaricus strains.