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PURPOSE: Previous literature showed that perceived social support, self-esteem and optimism all played critical roles in the developing of postpartum anxiety. However, the mechanisms of influence were still unclear. This study aimed to explore the underlying mechanism of the relationship among perceived social support, self-esteem, optimism and postpartum anxiety. METHOD: 756 women within one year after childbirth were surveyed using the Perceived Social Support Scale, Self-Assessment of Anxiety Scale, Self-Esteem Scale and Life Orientation Test Questionnaire. Pearson correlation analyses were performed to determine the direction and size of the all variables. The mediation model and the moderated mediation model were performed using the PROCESS macro. RESULTS: Postpartum anxiety negatively correlated with perceived social support, self-esteem and optimism. A significant positive relationship existed among perceived social support, self-esteem and optimism. Self-esteem played a mediating role in the association between perceived social support and postpartum anxiety, with a mediating effect value of - 0.23. Optimism moderated the mediating process by which perceived social support affected postpartum anxiety via self-esteem. At the three levels of optimism (mean minus 1 SD, mean and mean plus 1 SD), the mediating effect values of self-esteem in the relationship between perceived social support and postpartum anxiety tended to diminish. CONCLUSION: Self-esteem partially mediated the relationship between perceived social support and postnatal anxiety, and this mediating process was moderated by optimism.

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OBJECTIVE: To explore the trajectories and predictors of symptoms of depression in Chinese women from early pregnancy to 3 months after birth. DESIGN: Prospective cohort study. SETTING: Several maternal and child health care institutions and obstetric departments of general hospitals in Beijing, Jiangsu, Hunan, Sichuan, Shandong, Guangdong, and Shanxi provinces in China. PARTICIPANTS: Chinese women (N = 667) during pregnancy and the postpartum period. METHODS: From August 2019 to June 2020, participants from several tertiary hospitals in China who completed at least three measurements during early pregnancy to 3 months after birth (from time point 1 to time point 5) were included for data analysis. We used the self-administered basic information questionnaire and the Edinburgh Postnatal Depression Scale for follow-up. We used Mplus version 8.3 to construct the growth mixture modeling and SPSS version 25.0 to carry out logistic regression analysis. RESULTS: We found three potential trajectories of symptoms of depression during pregnancy and the postpartum period: the down-then-up healthy group (Class 1, 68.5%), steady-growth moderate-risk group (Class 2, 27.5%), and up-then-down high-risk group (Class 3, 4.0%). Multinomial logistic regression analysis showed that being pregnant for the first time, being a company employee, being less satisfied with the living environment, and the occurrence of negative life events were significant predictors of the Class 2 trajectory, whereas younger age, being less satisfied with food, and the occurrence of negative life events were predictors of the Class 3 trajectory. CONCLUSION: The trajectories of symptoms of depression during pregnancy and the postpartum period among Chinese women showed significant group heterogeneity. The trajectory categories were influenced not only by demographics and pregnancy-related factors but also by maternal subjective feelings.

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Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease characterized by an excessive accumulation of triacylglycerol in the liver. Autophagy is a lysosome-dependent degradation product recovery process, which widely occurs in eukaryotic cells, responsible for the vital maintenance of cellular energy balance. Previously published studies have demonstrated that autophagy is closely related to NAFLD occurrence and maternal obesity increases the susceptibility of offspring to non-alcoholic fatty liver disease, however, the underlying mechanism of this remains unclear. In the present study, NAFLD mouse models (offspring of an obese mother mouse via high-fat feeding) were generated, and the physiological indices of the liver were observed using total cholesterol, triglyceride, high-density lipoprotein and low-density lipoprotein serum assay kits. The morphological changes of the liver were also observed via HE, Masson and oil red O staining. Reverse transcription-quantitative-PCR and western blotting were performed to detect changes of autophagy-related genes in liver or fibrosis marker proteins (α-smooth muscle actin or TGF-ß1). Changes in serum inflammatory cytokine IL-6 levels were determined via ELISA. The results of the present study demonstrated that the offspring of an obese mother were more likely to develop NALFD than the offspring of a chow-fed mother, due to their increased association with liver fibrosis. When feeding continued to 17 weeks, the worst cases of NAFLD were observed and the level of autophagy decreased significantly compared with the offspring of a normal weight mouse. In addition, after 17 weeks of feeding, compared with the offspring of a chow-fed mother, the offspring of an obese mouse mother had reduced adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) phosphorylation levels and increased mammalian target of rapamycin (mTOR) phosphorylation levels. These results suggested that a reduced level of AMPK/mTOR mediated autophagy may be of vital importance for the increased susceptibility of offspring to NAFLD caused by maternal obesity. In conclusion, the current study provided a new direction for the treatment of NAFLD in offspring caused by maternal obesity.

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Tumour necrosis factor-α (TNF-α), a crucial cytokine, has various homeostatic and pathogenic bioactivities. The aim of this study was to assess the neuroprotective effect of ketamine against TNF-α-induced motor dysfunction and neuronal necroptosis in male C57BL/6J mice in vivo and HT-22 cell lines in vitro. The behavioural testing results of the present study indicate that ketamine ameliorated TNF-α-induced neurological dysfunction. Moreover, immunohistochemical staining results showed that TNF-α-induced brain dysfunction was caused by necroptosis and microglial activation, which could be attenuated by ketamine pre-treatment inhibiting reactive oxygen species production and mixed lineage kinase domain-like phosphorylation in hippocampal neurons. Therefore, we concluded that ketamine may have neuroprotective effects as a potent inhibitor of necroptosis, which provides a new theoretical and experimental basis for the application of ketamine in TNF-α-induced necroptosis-associated diseases.

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Beta (ß)-carotene (C40H56; a provitamin) is a particularly important carotenoid for human health. Many studies have focused on engineering Escherichia coli as an efficient heterologous producer of ß-carotene. Moreover, several strains with potential for use in the industrial production of this provitamin have already been constructed via different metabolic engineering strategies. In this study, we aimed to improve the ß-carotene-producing capacity of our previously engineered E. coli strain ZF43ΔgdhA through further gene deletion and metabolic pathway manipulations. Deletion of the zwf gene increased the resultant strain's ß-carotene production and content by 5.1 and 32.5%, respectively, relative to the values of strain ZF43ΔgdhA, but decreased the biomass by 26.2%. Deletion of the ptsHIcrr operon further increased the ß-carotene production titer from 122.0 to 197.4 mg/L, but the provitamin content was decreased. Subsequently, comparative transcriptomic analysis was used to explore the dynamic transcriptional responses of the strains to the blockade of the pentose phosphate pathway and inactivation of the phosphotransferase system. Lastly, based on the analyses of comparative transcriptome and reduction cofactor, several strategies to increase the NADPH supply were evaluated for enhancement of the ß-carotene content. The combination of yjgB gene deletion and nadK overexpression led to increased ß-carotene production and content. The best strain, ECW4/p5C-nadK, produced 266.4 mg/L of ß-carotene in flask culture and 2,579.1 mg/L in a 5-L bioreactor. The latter value is the highest reported from production via the methylerythritol phosphate pathway in E. coli. Although the strategies applied is routine in this study, the combinations reported were first implemented, are simple but efficient and will be helpful for the production of many other natural products, especially isoprenoids. Importantly, we demonstrated that the use of the methylerythritol phosphate pathway alone for efficient ß-carotene biosynthesis could be achieved via appropriate modifications of the cell metabolic functions.

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In natural produced bacteria, ß-carotene hydroxylase (CrtZ) and ß-carotene ketolase (CrtW) convert ß-carotene into astaxanthin. To increase astaxanthin production in heterologous strain, simple and effective strategies based on the co-expression of CrtZ and CrtW were applied in E. coli. First, nine artificial operons containing crtZ and crtW genes from different sources were constructed and, respectively, introduced into E. coli ZF237T, a ß-carotene producing host. Among the nine resulting strains, five accumulated detectable amounts of astaxanthin ranging from 0.49 to 8.07 mg/L. Subsequently, the protein fusion CrtZ to CrtW using optimized peptide linkers further increased the astaxanthin production. Strains expressing fusion proteins with CrtZ rather than CrtW attached to the N-terminus accumulated much more astaxanthin. The astaxanthin production of the best strain ZF237T/CrtZAs-(GS)1-WBs was 127.6% and 40.2% higher than that of strains ZF237T/crtZAsWBs and ZF237T/crtZBsWPs, respectively. The strategies depicted here also will be useful for the heterologous production of other natural products.

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OBJECTIVES: To investigate the capacity of a genome-reduced Bacillus subtilis strain as chassis cell for acetoin production from xylose. RESULTS: To endow the genome-reduced Bacillus subtilis strain BSK814 with the ability to utilize xylose, we inserted a native xyl operon into its genome and deleted the araR gene. The resulting strain BSK814A2 produced 2.94 g acetoin/l from 10 g xylose/l, which was 39% higher than control strain BSK19A2. The deletion of the bdhA and acoA genes further improved xylose utilization efficiency and increased acetoin production to 3.71 g/l in BSK814A4. Finally, BSK814A4 produced up to 23.3 g acetoin/l from 50 g xylose/l, with a yield of 0.46 g/g xylose. Both the titer and yield were 39% higher than those of control strain BSK19A4. CONCLUSIONS: As a chassis cell, genome-reduced B. subtilis showed significantly improved capacity for the production of the overflow product acetoin from xylose compared with wild-type strain.

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We present a spatial-frequency domain (SFD) fluorescence tomography (FT) for acquiring three-dimensional fluorophore distribution in turbid media. The approach uses a composited epi-illumination of multi-frequency sinusoidal patterns on a sample of semi-infinite geometry and demodulates the measured data with a generalized phase shifting scheme to calculate the modulation transfer function (MTF) at each frequency. This method results in a significantly reduced number of the optical field measurements, as compared to those with separate illumination of single-frequency sinusoidal patterns, and, thereby, achieves a fast data acquisition that is desired for a dynamic imaging application. Fluorescence yield images are recovered with the normalized Born formulated inversion of the diffusion model by simultaneously using the multi-frequency MTFs. Simulative and experimental reconstructions are performed in comparison with the single-frequency scheme to validate the proposed algorithm. The results suggest that adoption of the multi-frequency strategy to the SFD-FT can substantially improve the reconstruction quality, as well as its imaging resolution and quantitative accuracy.

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BACKGROUND: Spatial frequency domain (SFD) measurement allows rapid and non-contact wide-field imaging of the tissue optical properties, thus has become a potential tool for assessing physiological parameters and therapeutic responses during photodynamic therapy of skin diseases. The conventional SFD measurement requires a reference measurement within the same experimental scenario as that for a test one to calibrate mismatch between the real measurements and the model predictions. Due to the individual physical and geometrical differences among different tissues, organs and patients, an ideal reference measurement might be unavailable in clinical trials. To address this problem, we present a reference-free SFD determination of absorption coefficient that is based on the modulation transfer function (MTF) characterization. METHODS: Instead of the absolute amplitude that is used in the conventional SFD approaches, we herein employ the MTF to characterize the propagation of the modulated lights in tissues. With such a dimensionless relative quantity, the measurements can be naturally corresponded to the model predictions without calibrating the illumination intensity. By constructing a three-dimensional database that portrays the MTF as a function of the optical properties (both the absorption coefficient µ a and the reduced scattering coefficient [Formula: see text]) and the spatial frequency, a look-up table approach or a least-square curve-fitting method is readily applied to recover the absorption coefficient from a single frequency or multiple frequencies, respectively. RESULTS: Simulation studies have verified the feasibility of the proposed reference-free method and evaluated its accuracy in the absorption recovery. Experimental validations have been performed on homogeneous tissue-mimicking phantoms with µ a ranging from 0.01 to 0.07 mm-1 and [Formula: see text] = 1.0 or 2.0 mm-1. The results have shown maximum errors of 4.86 and 7% for [Formula: see text] = 1.0 mm-1 and [Formula: see text] = 2.0 mm-1, respectively. We have also presented quantitative ex vivo imaging of human lung cancer in a subcutaneous xenograft mouse model for further validation, and observed high absorption contrast in the tumor region. CONCLUSIONS: The proposed method can be applied to the rapid and accurate determination of the absorption coefficient, and better yet, in a reference-free way. We believe this reference-free strategy will facilitate the clinical translation of the SFD measurement to achieve enhanced intraoperative hemodynamic monitoring and personalized treatment planning in photodynamic therapy.

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OBJECTIVE: To explore activity laws of mitochondrial complex II in patients of deficiency-cold syndrome (DCS) and deficiency-heat syndrome (DHS) under various ambient temperatures. METHODS: Subjects were recruited by questionnaire and expert diagnosis from grade 1 - 3 undergraduates at Henan College of Traditional Chinese Medicine in November 2012, and assigned to a normal control group, the DCS group, and the DHS group, 20 in each group. Their venous blood samples were collected at two different temperature conditions. Activities of mitochondrial complex II were measured by spectrophotometry. RESULTS: (1) Comparison of mitochondrial complex It under various ambient temperatures: Compared with room temperature in the same group, activity values were all increased in the normal control group at cold temperature with significant difference (P <0.05), but there was no significant difference in the DCS group and the DHS group (P >0. 05). Compared with the normal control group, activity values of complex H were reduced in the DCS group at cold and room temperatures with significant difference (P <0.05). Compared with the DCS group, activity values of complex It were increased in the DHS group with significant difference (P <0. 05). (2) Changes of adjustment rates: Compared with room temperature, the adjustment rate all rose at cold temperature in the normal control group and the DHS group with significant difference (P <0.05), but with no significant difference found in the DCS group (P >0. 05). Compared with the normal control group at the same temperature, the adjustment rate in the DHS group and the DCS group was all reduced at cold and room temperatures with significant difference (P <0. 05). There were no significant difference in the adjustment rate between the DHS group and the DCS group (P > 0. 05). CONCLUSIONS: Environment temperature can affect the activity of mitochondrial complex II with different influence degrees on different syndrome types of people, but its change trend are basically identical.

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This study reports the development of an electrochemiluminescent (ECL) immunosensor for ultrasensitive detection of phenylethanolamine A (PA) based on CdSe quantum dots (QDs) and gold nanoparticles (GNPs). The GNPs/ovalbumin-PA/anti-PA-QD immunosensor was fabricated layer by layer using GNPs as substrates and electron transport accelerators. The use of GNPs greatly enhanced the sensitivity for detecting PA due to the excellent electron transportation ability and the large surface area of GNP carriers allowing several binding events of ovalbumin-PA on each nanosphere. Transmission electron microscopy images (TEM), photoluminescence spectra, ultraviolet-visible absorption spectra and dynamic light scattering (DLS) were used to characterize the QDs and GNPs. The sensor was characterized with electrochemical impedance spectra (EIS), and a strong ECL emission of the modified electrode could be observed during the cathodic process of S2O8(2-) and QDs in air-saturated PBS buffer containing 0.1 M K2S2O8 and 0.1 M KCl (pH 7.4). With a competitive immunoassay format, the ECL signal depended linearly on the logarithm of the phenylethanolamine A concentration within a range of 0.02 ng mL(-1) to 50 ng mL(-1), and the detection limit was 0.0047 ng mL(-1), much lower than those reported in the literature. This ECL immunosensor is rapid, simple and sensitive with acceptable precision, and it will extend the application of QD ECL in immunoassays of ß-agonists and open new avenues for the detection of food additive residues in the future.

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An ultrasensitive electrochemiluminescence (ECL) immunosensor based on CdSe quantum dots (QDs) has been designed for the detection of clenbuterol. The immunosensor was fabricated by layer by layer and characterized with atomic force microscopic images (AFM) and electrochemical impedance spectra (EIS). In oxygen-saturated pH=9.0 Tris-HCl buffer, a strong ECL emission of QDs could be observed during the cathodic process due to the H2O2 product from electrochemical reduction of dissolved oxygen. Upon the formation of immunocomplex, the second antibody labeled with horseradish peroxidase was simply immobilized on the electrode surface. The ECL emission decreased since steric hindrance of the immunocomplex slowed down the electron-transfer speed of dissolved oxygen, and also could be greatly amplified by an enzymatic cycle to consume the self-produced coreactant. Using clenbuterol as model analyte, the ECL intensity was determined by the concentration of competitive immunoassay of clenbuterol with a wide calibration in the range of 0.05 ng mL(-1) to 1000 ng mL(-1), and a low detection limit was 0.02 ng mL(-1). The immunosensor shows good stability and fabrication reproducibility. It was applied to detecting practical samples with the satisfactory results. This immunosensing strategy opens a new avenue for detection of residue and application of QDs in ECL biosensing.

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Water-soluble CdSe quantum dots (QDs) have been prepared by using L-cysteine as the stabilizer in an aqueous phase under the optimized conditions. The characteristics and shapes of CdSe QDs have been proposed on the basis of UV-Vis and fluorescence spectra. A rapid analytical method for electrochemiluminescence (ECL) determination of nitrite has been developed on the basis of the quenching effect on anodic ECL emission of CdSe QDs under the optimum experimental conditions. In a neutral system and at a relatively low potential (+0.960 V), the ECL emission of CdSe QDs could be greatly enhanced by sulfite and could be gradually quenched by nitrite at an indium tin oxide (ITO) electrode. The proposed method may allow the measurement of nitrite ranging from 1 µM to 0.5 mM with a correlation coefficient of 0.9956 (n = 10) and a detection limit of 0.2 µM (3σ), and the relative standard deviation for 10 µM nitrite (n = 9) is 1.72 %. The proposed method could be adopted for the sensitive detection of ECL quenchers by using nitrite as a model molecule.

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