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Rice grain-shaped high Mn-doped anatase TiO2(TMO) nanocrystals have been fabricated through redox method at room temperature using several simple chemical reagents. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), transmission electron microscopy and High-resolution transmission electron microscopy (TEM & HRTEM). It indicates that the manganese element was successfully incorporated into the anatase TiO2 nanostructure, and the atomic Mn-to-Ti could reach up to 18.2%. We also analyzed the merits and weaknesses of the nanostructured TMO in electrochemistry by dint of some relevant measures. And the cause of influence on the TMO electrochemical properties was briefly discussed. [ABSTRACT FROM AUTHOR]

Studies the photofragmentation of dimethylsulfoxide using the molecular beam time-of-flight (TOF) mass spectrometric technique. Photochemistry of dimethylsulfoxide; Ab initio calculations; Theoretical and experimental values for selected bond dissociation energies.

The kinetic energy release spectra for SH resulting from the 193 nm laser photofragmentation of HSCH2CH2SH have been measured. On the basis of the observed maximum kinetic energy for the formation of HS+CH2CH2SH, a value of 74±2 kcal/mol is derived for the bond dissociation energy of HS–CH2CH2SH at 0 K [D0(HS–CH2CH2SH)]. Angular distribution measurements for SH yield an anisotropic parameter β=-0.4±0.1 for the HS+CH2CH2SH channel, indicating that the C–S bond fission is fast with respect to molecular rotation. The energetics for the formation of HS+CH2CH2SH from HSCH2CH2SH have been investigated using the Gaussian-2 (G2) and G2(MP3) ab initio quantum chemical procedures. The G2/G2(MP3) calculations give a prediction of 72.5 kcal/mol for D0(HS–CH2CH2SH), in excellent agreement with the experimental value. Ab initio first-order configuration interaction calculations have also been made to examine the possible excited state of HSCH2CH2SH involved in the photodissociation process and to rationalize the observed angular distribution for the HS+CH2CH2SH channel. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies acetophenone at 193 and 248 nanometer. Laser photofragmentation time-of-flight mass; Secondary products yield; Heats of formation; Ultraviolet photochemistry of alkyl ketones and related molecules.

Taxus chinensis var. mairei is a rare and endangered medicinal plant species distributed in China. In order to promote fast propagation and preserve the natural resources, conditions for in vitro germination and seedling development of embryos of T. chinensis var. mairei from Anhui or Zhejiang were investigated. Results showed that in vitro germination rate of excised embryos cultured under 14 hours photoperiod was higher than that in darkness. But, nearly all embryos germinated under 14 hours photoperiod failed to develop into seedlings. Comparatively, 23.3 and 36.3% of embryos from Anhui and Zhejiang, respectively, which germinated in darkness, developed into full seedlings. Addition of plant growth regulators [gibberellic acid (GA3), indole-3-acetic acid (IAA), 6-benzylaminopurine (BA)] and organic additives (casein hydrolysate and yeast extract) in mediums promoted germination and seedling development. (Woody plant medium) WPM medium supplemented with 0.5 mg L-1 GA3, 0.5 mg L-1 IAA, 0.5 mg L-1 BA and 1 g L-1 activated charcoal was optimal for the culture of embryos from Anhui, while WPM medium supplemented with 0.5 mg L-1 GA3, 500 mg L-1 casein hydrolysate and 1 g L-1 activated charcoal was optimum for embryos from Zhejiang. Moreover, the germination and seedling survival rate of embryos of T. chinensis var. mairei decreased with increasing maturity of the seeds. In conclusion, darkness during germination is necessary for subsequent seedling development and immature seeds are optimal for embryo culture of this species. [ABSTRACT FROM AUTHOR]

Objective: To achieve automatic segmentation, quantification, and grading of different regions of leopard spots fundus (FT) using deep learning technology. The analysis includes exploring the correlation between novel quantitative indicators, leopard spot fundus grades, and various systemic and ocular parameters. Methods: This was a cross-sectional study. The data were sourced from the Beijing Eye Study, a population-based longitudinal study. In 2001, a group of individuals aged 40 and above were surveyed in five urban communities in Haidian District and three rural communities in Daxing District of Beijing. A follow-up was conducted in 2011. This study included individuals aged 50 and above who participated in the second 5-year follow-up in 2011, considering only the data from the right eye. Color fundus images centered on the macula of the right eye were input into the leopard spot segmentation model and macular detection network. Using the macular center as the origin, with inner circle diameters of 1 mm, 3 mm, and outer circle diameter of 6 mm, fine segmentation of the fundus was achieved. This allowed the calculation of the leopard spot density (FTD) and leopard spot grade for each region. Further analyses of the differences in ocular and systemic parameters among different regions' FTD and leopard spot grades were conducted. The participants were categorized into three refractive types based on equivalent spherical power (SE): myopia (SE<-0.25 D), emmetropia (-0.25 D≤SE≤0.25 D), and hyperopia (SE>0.25 D). Based on axial length, the participants were divided into groups with axial length<24 mm, 24-26 mm, and>26 mm for the analysis of different types of FTD. Statistical analyses were performed using one-way analysis of variance, Kruskal-Wallis test, Bonferroni test, and Spearman correlation analysis. Results: The study included 3 369 participants (3 369 eyes) with an average age of (63.9±10.6) years; among them, 1 886 were female (56.0%) and 1, 483 were male (64.0%). The overall FTD for all eyes was 0.060 (0.016, 0.163); inner circle FTD was 0.000 (0.000, 0.025); middle circle FTD was 0.030 (0.000, 0.130); outer circle FTD was 0.055 (0.009, 0.171). The results of the univariate analysis indicated that FTD in various regions was correlated with axial length (overall: r =0.38, P <0.001; inner circle: r =0.31, P <0.001; middle circle: r =0.36, P <0.001; outer circle: r =0.39, P <0.001), subfoveal choroidal thickness (SFCT) (overall: r =-0.69, P <0.001; inner circle: r =-0.57, P <0.001; middle circle: r =-0.68, P <0.001; outer circle: r =-0.72, P <0.001), age (overall: r =0.34, P <0.001; inner circle: r =0.30, P <0.001; middle circle: r =0.31, P <0.001; outer circle: r =0.35, P <0.001), gender (overall: r =-0.11, P <0.001; inner circle: r =-0.04, P <0.001; middle circle: r =-0.07, P <0.001; outer circle: r =-0.11, P <0.001), SE (overall: r =-0.20; P <0.001; inner circle: r =-0.19, P <0.001; middle circle: r =-0.20, P <0.001; outer circle: r =-0.20, P <0.001), uncorrected visual acuity (overall: r =-0.18, P <0.001; inner circle: r =-0.26, P <0.001; middle circle: r =-0.24, P <0.001; outer circle: r =-0.22, P <0.001), and body mass index (BMI) (overall: r =-0.11, P <0.001; inner circle: r =-0.13, P <0.001; middle circle: r =-0.14, P <0.001; outer circle: r =-0.13, P <0.001). Further multivariate analysis results indicated that different region FTD was correlated with axial length (overall: β =0.020, P <0.001; inner circle: β =-0.022, P <0.001; middle circle: β =0.027, P <0.001; outer circle: β =0.022, P <0.001), SFCT (overall: β =-0.001, P <0.001; inner circle: β =-0.001, P <0.001; middle circle: β =-0.001, P <0.001; outer circle: β =-0.001, P <0.001), and age (overall: β =0.002, P <0.001; inner circle: β =0.001, P <0.001; middle circle: β =0.002, P <0.001; outer circle: β =0.002, P <0.001). The distribution of overall ( H =56.76, P <0.001), inner circle ( H =72.22, P <0.001), middle circle ( H =75.83, P <0.001), and outer circle ( H =70.34, P <0.001) FTD differed significantly among different refractive types. The distribution of overall ( H =373.15, P <0.001), inner circle ( H =367.67, P <0.001), middle circle ( H =389.14, P <0.001), and outer circle ( H =386.89, P <0.001) FTD differed significantly among different axial length groups. Furthermore, comparing various levels of FTD with systemic and ocular parameters, significant differences were found in axial length ( F =142.85, P <0.001) and SFCT ( F =530.46, P <0.001). Conclusions: The use of deep learning technology enables automatic segmentation and quantification of different regions of theFT, as well as preliminary grading. Different region FTD is significantly correlated with axial length, SFCT, and age. Individuals with older age, myopia, and longer axial length tend to have higher FTD and more advanced FT grades.

Objective: To investigate the clinicopathological characteristics of plurihormonal PIT1-lineage pituitary neuroendocrine tumors. Methods: Forty-eight plurihormonal PIT1-lineage tumors were collected between January 2018 and April 2022 from the pathological database of Sanbo Brain Hospital, Capital Medical University. The related clinical and imaging data were retrieved. H&E, immunohistochemical and special stains were performed. Results: Out of the 48 plurihormonal PIT1-lineage tumors included, 13 cases were mature PIT1-lineage tumors and 35 cases were immature PIT1-lineage tumors. There were some obvious clinicopathological differences between the two groups. Clinically, the mature plurihormonal PIT1-lineage tumor mostly had endocrine symptoms due to increased hormone production, while a small number of immature PIT1-lineage tumors had endocrine symptoms accompanied by low-level increased serum pituitary hormone; patients with the immature PIT1-lineage tumors were younger than the mature PIT1-lineage tumors; the immature PIT1-lineage tumors were larger in size and more likely invasive in imaging. Histopathologically, the mature PIT1-lineage tumors were composed of large eosinophilic cells with high proportion of growth hormone expression, while the immature PIT1-lineage tumors consisted of chromophobe cells with a relatively higher expression of prolactin; the mature PIT1-lineage tumors had consistently diffuse cytoplasmic positive staining for keratin, while the immature PIT1-lineage tumors had various expression for keratin; the immature PIT1-lineage tumors showed more mitotic figures and higher Ki-67 proliferation index; in addition, 25.0% (12/48) of PIT1-positive plurihormonal tumors showed abnormal positive staining for gonadotropin hormones. There was no significant difference in the progression-free survival between the two groups ( P =0.648) by Kaplan-Meier analysis. Conclusions: Plurihormonal PIT1-lineage tumor belongs to a rare type of PIT1-lineage pituitary neuroendocrine tumors, most of which are of immature lineage. Clinically increased symptoms owing to pituitary hormone secretion, histopathologically increased number of eosinophilic tumor cells with high proportion of growth hormone expression, diffusely cytoplasmic keratin staining and low proliferative activity can help differentiate the mature plurihormonal PIT1-lineage tumors from the immature PIT1-lineage tumors. The immature PIT1-lineage tumors have more complicated clinicopathological characteristics.

The current study aimed to investigate the clinical characteristics of Parkinson's disease (PD) patients with concomitant periodic limb movements in sleep (PLMS). The clinical data of 36 PD patients who underwent polysomnography (PSG) in Beijing Tiantan Hospital from October 2018 to July 2022 were collected. Unified Parkinson's Disease Rating Scale 3.0 and Hoehn & Yahr (H-Y) stage were used to evaluate the disease severity. Patients were divided into two groups: the PLMS+group periodic limb movements in sleep index [(PLMSI)≥15 times/h] and the PLMS-group (PLMSI<15 times/h), using the PLMSI 15 times/h as the cut-off value. The clinical characteristics between the two groups were compared. There were 15 patients (42%) in the PLMS+group and 21 patients (58%) in the PLMS-group, among which 12 patients (12/15) in the PLMS+group and 9 patients (42.9%) in the PLMS-group had rapid eye movement sleep behavior disorder (RBD). The rate of RBD in PLMS+group was higher than that in PLMS-group ( P <0.05). There was statistically significant difference in the blood folate level between the PLMS-group and PLMS+group [6.20 (5.14, 11.70) ng/ml vs 4.41 (3.07, 5.64) ng/ml] ( P< 0.01). Folate deficiency was more common in the PLMS+group, while no statistically significant differences were found in homocysteine and ferritin levels (both P >0.05). Four patients in the PLMS+group had falling experience, while 14.3% (3/21) patients in the PLMS-group had falling experience. Patients in the PLMS+group were more likely to fall. The PLMS+group had higher arousal index according to PSG [PLMS-group: 11.90 (9.10, 15.80) times/h; PLMS+group: 21.50 (19.35, 29.90) times/h] ( P< 0.05). No statistically significant differences in other sleep parameters were detected between the two groups (all P >0.05). Meanwhile, the apnea-hypopnea index (AHI) in both groups was higher than normal (<5 times/h), of which the PLMS-group was 9.80 (4.70, 22.20) times/h and the PLMS+group was 8.20 (1.70, 11.15) times/h, indicating that PD patients were more likely to experience sleep apnea and hypopnea. PD patients with PLMS had lower folate level, higher risk for falls, higher sleep arousal index, more sleep fragmentation, and higher prevalence of RBD.

Objective: To investigate the expression and function of collagen type ⅩⅦ α1 (COL17α1) in aging mouse skin and its effect on the stemness and proliferation of human epidermal stem cells (ESCs), and to explore the mechanism of related microRNA (miR) in intervening the expression of COL17α1 of human ESC. Methods: The method of experimental research was used. Twelve 2-month-old (young) and twelve 24-month-old (aged) male C57BL/6J mice were selected, and full-thickness skin samples from their upper back were taken for follow-up detection. After hematoxylin-eosin staining of the full-thickness skin samples of young mice and aged mice, the structure of the epidermis was observed and the thickness of the epidermis was measured; the morphology of epidermal basement membrane and hemidesmosomes were observed by transmission electron microscopy, and the hemidesmosomes were counted; the mRNA and protein expressions of COL17α1 were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blotting respectively, and the protein expression and distribution of COL17α1 was observed and detected by immunofluorescence method. The fresh foreskin tissue discarded after surgery was obtained from 3 healthy men aged 20-30 years who underwent circumcision at the Fourth Medical Center of PLA General Hospital, ESCs were extracted and well-grown cells were wsed for follow-up experiments. According to the random number table (the same grouping method below), ESCs were divided into blank control group, transfection reagent control group, empty vector plasmid group, and COL17α1 knockdown plasmid group with corresponding treatment. After 48 hours of culture, the mRNA expression of COL17α1 was detected by real-time fluorescent quantitative RT-PCR, the protein expressions of COL17α1 and cytokeratin 14 (CK14) were detected by Western blotting, and the cell proliferation level was detected by cell counting kit 8. miRs that might act on the 3' non-coding region of COL17α1 mRNA were screened through DIANA, miRTarBase, miRNAMap, TargetScan, and microRNA databases. The ESCs were divided into negative control group transfected with miR mimic negative control and each miR mimic group transfected with each of the previously screened miR mimics. Forty-eight hours after transfection, the protein expression of COL17α1 was detected by Western blotting. Based on the sequencing data set GSE114006 in Gene Expression Omnibus (GEO), the GEO2R tool was used to statistically analyze the expression of the previously screened miRs that could cause the reduction of COL17α1 protein expression in the skin of 30 young (18-25 years old) and 30 elderly (>70 years old) human skins. The full-thickness skin samples of young mice and aged mice were taken, and the expressions of increased miRs in the aforementioned aged human skin were detected by real-time fluorescent quantitative RT-PCR. Two batches of human ESCs were taken, the first batch was divided into COL17α1 wild type+miR-203b-3p negative control group and COL17α1 wild type+miR-203b-3p mimic group, and the second batch was divided into COL17α1 mutant+miR-203b-3p negative control group and COL17α1 mutant+miR-203b-3p mimic group. Each group of ESC was transfected with corresponding sequences respectively. Forty-eight hours later, the luciferase reporter gene detection kit was used to detect the gene expression level of COL17α1. The number of samples in the tissue experiment was 6, and the number of samples in the cell experiment was 3. Data were statistically analyzed with independent sample t test, one-way analysis of variance, least significant difference test or Dunnett's test, Mann-Whitney U test or Kruskal-Wallis H test. Results: Compared with those of young mice, the boundary between the epidermis and the dermis of the aged mice skin was blurred and the cell layers were less, and the thickness of epidermis was significantly thinner ( Z =-2.88, P <0.01); the morphology of basement membrane was discontinuous, with less unevenly distributed hemidesmosomes at the epidermis-dermis junction, and the number of hemidesmosomes was significantly reduced ( Z =-2.91, P <0.01); the mRNA and protein expression levels of COL17α1 in the skin of aged mice were significantly decreased (with t values of 10.61 and 6.85, respectively, P <0.01). Compared with those of young mice, the protein expression of COL17α1 in the basal layer of epidermis and the bulb of hair follicle in the skin of aged mice was significantly decreased ( Z =-2.24, P <0.05). After 48 hours of culture, the protein expression levels of COL17α1 in ESCs of blank control group, transfection reagent control group, empty vector plasmid group, and COL17α1 knockdown plasmid group were 1.00±0.27, 1.12±0.21, 1.13±0.23, and 0.42±0.18, respectively. Compared with those of blank control group, the mRNA and protein expression levels of COL17α1, the protein expression level of CK14, and the proliferation level of ESCs in transfection reagent control group and empty vector plasmid group did not change significantly ( P >0.05), while these indexes in COL17α1 knockdown plasmid group were significantly decreased ( P <0.05 or P <0.01). miR-203a-3p, miR-203b-3p, miR-512-5p, miR-124-3p, miR-28-5p, miR-590-3p, and miR-329-5p might bind to the 3' non-coding region of COL17α1 mRNA. Forty-eight hours after transfection, compared with 1.000±0.224 in negative control group, the protein expression level of COL17α1 in ESCs of miR-329-5p mimic group, miR-203b-3p mimic group, and miR-203a-3p mimic group decreased significantly (0.516±0.188, 0.170±0.025, and 0.235±0.025, with t values of 3.17, 5.43, and 5.07, respectively, P <0.05 or P <0.01). Only the expression level of miR-203b-3p in the skin of the elderly was significantly higher than that of the young ( t =3.27, P <0.01). The expression level of miR-203b-3p in the skin of aged mice was significantly higher than that of young mice ( Z =-2.88, P <0.01). Forty-eight hours after transfection, the gene expression level of COL17α1 in ESCs of COL17α1 wild type+miR-203b-3p mimic group was significantly lower than that of COL17α1 wild type+miR-203b-3p negative control group ( t =7.66, P <0.01). The gene expression level of COL17α1 in ESCs of COL17α1 mutant+miR-203b-3p mimic group was similar to that of COL17α1 mutant+miR-203b-3p negative control group ( P >0.05). Conclusions: The mRNA and protein expression levels of COL17α1 decrease with age increasing in mice, which may lead to the detachment of mouse ESC from the epidermal basement membrane. Decreased expression of COL17α1 can inhibit the expression of CK14 and ESC proliferation, which may be responsible for the thinning of the epidermis and slower wound healing in aged human skin. The increased expression of miR-203b-3p in aged mouse skin can target and bind to the 3' non-coding region of COL17α1 mRNA, hindering the post-transcriptional translation process, thus resulting in decreased COL17α1 protein expression.

COVID-19 had caused the epidemic in Wuhan of China in December 2019. The asymptomatic infection of COVID-19 was found with the further research. This paper summarizes the discovery of the asymptomatic infection cases, analyzes their outcomes and transmission risks, and put forward the targeted suggestions for the prevention and control of asymptomatic infection of COVID-19 according to the existing problems in epidemic response.

Objective: To establish a standard operation procedure (SOP) for ribosome genotyping (ribotyping) on Clostridioides ( C. ) difficile , supplement and verify ribotyping typing library, so as to improve the comparability of data between different laboratories and to develop surveillance network of C. difficil in China. Methods: Molecular typing of 54 reference strains from the United States and Europe of C. difficile were performed by using the SOP referencing correspondence from abroad and from our laboratory with a BioNumerics 7.6 software to estimate the reference library of types of C. difficile . Identification of 374 clinical and animal isolates of C. difficile from 13 cities in China between 2010 and 2018, to supplement the library information. Kappa test was used to evaluate the consistency. Results: Results of capillary electrophoresis of reference strains appeared clear and stable, which guaranteed the clustering results being fast and accurate. Results from the supplementary typing showed that there were 84 types of isolates, of which 25 RT types were consistent with reference strains from abroad, while 58 RT types were different from referenced types. In the 40 referenced types, 15 RT types were not found in this study. In the consistency evaluation, the Kappa value was 0.891 and ( P <0.01), showing the two Molecular typing as consistent and with close resemblance. Conclusions: The result of capillary electrophoresis by applying SOP for ribotyping on C. difficile base on QIAxcel capillary electrophoresis system, appeared clear and stable. The standardized library seemed more easily used for comparability and data sharing between the laboratories.

Complex vertebral malformation (CVM) is a recently described monogenic autosomal recessive hereditary defect of Holstein dairy cattle that causes premature birth, aborted fetuses and stillborn calves. Guanine is substituted by thymine (G>T) in the solute carrier family 35 member A3 gene (SLC35A3). A valine is changed to a phenylalanine at position 180 of uridine 5'-diphosphate-N-acetyl-glucosamine transporter protein. CVM is expected to occur in many countries due to the widespread use of sire semen. We developed a created restriction site PCR (CRS-PCR) method to diagnose CVM in dairy cows. This was tested on 217 cows and 125 bulls selected randomly from a Holstein cattle population in south China. Five Holstein cows and five Holstein bulls were identified to be CVM carriers; the percentages of CVM carriers were estimated to be 2.3, 4.0 and 2.9% in the cows, bulls and entire Holstein cattle sample, respectively.

A simple and accurate reversed-phase high performance liquid chromatographic method to determine puerarin in three traditional Chinese patent medicines, namely "Xiao'er qingganling" tablet, "Buchang xinnaoxintong" capsulae and "Ganmao qingre" granule is described. "Xiao'er qingganling" tablet and "Buchang xinnaoxintong" capsulae were extracted with methanol in an ultrasonic bath and "Ganmao qingre" granule was extracted with water and ethanol. After being centrifuged and filtered, the samples were separated on an ODS column with a mobile phase of 100 mmol/L ammonium acetate buffer (pH 5.0)-methanol(75:25, volume ratio). The flow rate was 0.8 mL/min, and the detection wavelength was 250 nm. The calibration curve was linear in the range of 2 mg/L-20 mg/L puerarin (r = 0.9999). The average recoveries were 99.0%, 93.4% and 97.5% for "Xiao'er qingganling" tablet, "Buchang xinnaoxintong" capsulae, "Ganmao qingre" granule respectively. The average contents of puerarin in the medicines were 3.48 mg/g, 1.08 mg/g and 1.52 mg/g (sucrose), and the relative standard deviations were 1.9%, 1.4% and 1.4% respectively.

The effect of forced depletion of brain norepinephrine (NE) on the onset of hibernation was observed in the ground squirrel (Citellus dauricus) by intraventricular injection of 6-hydroxydopamine (6-OHDA). The results showed: (1) Intraventricular injection of 100-200 micrograms 6-OHDA, which depleted 50-60% NE, markedly facilitated the onset of hibernation, i.e. the average induction period for hibernation in the treated animals was significantly shorter than that of the natural hibernating animals. (2) The average total torpor time in the treated animals was longer than that of natural hibernating animals. (3) All hibernating animals treated with 6-OHDA were able to wake up from deep hibernation spontaneously and undergo normal hibernation bouts. The results indicate the decrease of NE system activity in brain is one important factor in triggering the onset of hibernation.