Aquatic plant duckweed can enrich high concentration of arsenic, it is thus used as the representative of phytofiltration.The mechanism of arsenic tolerance in duckweeds has received much concern.In this study, synchrotron radiation X-ray fluorescence (SRXRF) and X-ray absorption near edge structure (XANES) techniques were used to study the micro-distribution and speciation of arsenic in natural As-rich duckweed from lead-zinc mine.Two monolithic duckweeds, FP1 and FP2, were analyzed by micro SRXRF, setting single point scan time and spot size were 5 s, 70 μm×80 μm and 2 s, 100 μm×100 μm respectively.Six points of FP2 were selected and analyzed by micro XANES in energy range of 11.81-11.96 keV.Pressed-pellet duckweed was analyzed by bulk XANES in energy range of 11.67-12.27 keV.The result showed that As(Ⅲ) was the major speciation of duckweed from bulk XANES and micro-XANES data.SRXRF micro analysis showed that arsenic had significant vein distribution in duckweed, and was not spread into the photosynthetic mesophyll within certain concentration, which may reduce the leaf toxicity triggered by arsenic.This vein distribution may play a role in arsenic tolerance in duckweed.

Objective To observe the growth situation of Blastocystis hominis in vitro and select the optimal method for culti?vation of B. hominis in different media. Methods Ten positive stools with B. hominis were inoculated in three different media for cultivating,namely 1640,Jone’s medium and vitro medium. And the stools with good growth status and high quantities of B. hominis were chosen to inoculate in the three media with equal amount after subcultivation,and the number of B. hominis was counted every 24 h for ten days,and the morphological changes and growth status were also observed. Results The densities of B. hominis in the 1640 and Jone’s medium were higher than that in the vitro medium 48 h after the inoculation. The same stool sample was inoculated to the three different media and observed for ten days,and the results indicated that the growth of B. homi?nis presented regular changes in the three media,the growth peaks were on the third,sixth and ninth day post inoculation;and the density of B. hominis was the highest in the Jone’s medium. The morphology of B. hominis was the clearest and most dynamic in the vitro medium,while various reproductive forms were observed in the Jone’s medium. Conclusion Jone’s medium is suitable for the growth of B. hominis and can be the first choice for the cultivation of B. hominis in vitro,and vitro medium is the best medium for observing the growth situation of B. hominis.

Objective To analyze the fractional proteins and immunoreactivity of the soluble antigens from Babesia microti (B.microti),and find the candidate antigens for diagnosis with high sensitivity and specificity.Methods BALB/c mice were inoculated with B.microti-infected red blood cells by intraperitoneal injection.The B.microti were collected from the infected red blood cells when the infection rate reached its peak (infection rate ＞70％),then the soluble antigens were extracted by repeated freezing-thawing and ultrasonic method.The mice sera before and after the infection with B.microti for 7,14,21,28,35,42,49 and 56 days were also collected.The polyacrylamide gel electrophoresis (SDS-PAGE) was used to analyze protein components of the soluble antigens of B.microti and the Western blot was used to analyze the immunoreactivity of the soluble antigens with the pooled mice sera before and after the infection.The specific positive protein bands were identified by Liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS),and the amino acid sequences of the proteins were analyzed by bioinformatics tools.Results The results from SDS-PAGE analysis indicated that the soluble antigens of B.microti showed distinct protein bands with the range between 12 and 185 × 103 (kDa,relative molecular mass,Mr),among which 9 main bands and 12 minor bands were obtained.In the Western blot analysis,the protein bands with Mr at 40 and 45 kDa could be recognized by pooled mice sera 7 days after infection;the protein bands with Mr at 40,45,54 and 95 kDa could be recognized by pooled mice sera 14 days after infection;the protein bands with Mr at 27,40,45,54,95 and 110 kDa could be recognized by pooled mice sera 21 days after infection.While,the protein bands with Mr at 27,40,45,54,95,1 10 kDa and other weak-reactive bands were recognized by pooled mice sera 28-56 days after infection,and the reaction became stronger with the infection continued.There were 336 proteins,including surface antigen,heat shock protein 70,seroreactive antigen,Eta subunit of chaperonin containing t-complex polypeptide 1 and unnamed protein products,were identified as the components of soluble antigens after mass spectrometry and sequence analysis.Conclusion The 40,45 and 54 kDa protein components from the soluble antigens of B.microti may be ideal candidate antigens for diagnosis,andtheir potential applications in diagnosing of human babesiosis deserve further study.

Objective To establish A1E3 and B1C4 monoclonal antibody-based ELISA for detecting circulating antigen of Schistosoma japonicum and explore its application value in the field. Methods The characteristics of A1E3 and B1C4 monoclonal antibodies were analyzed by SDS-PAGE and Western blotting. The SEA-based ELISA was used to evaluate the titers of A1E3 and B1C4. The orthogonal test was used to determine the best concentration of coating antibody B1C4 and optimal working concentra-tion of A1E3-HRP. Under the optimal conditions,the serum samples of 20 acute schistosomiasis cases,46 chronic schistosomiasis cases,and 20 control sera were tested to evaluate its detection sensitivity and specificity. Seventy-two antibody positive serum sam-ples from Jiangling County of Hubei Province were detected and compared to a commercially available ELISA kit,to evaluate the detection effects of this method. Results The results of SDS-PAGE demonstrated that the purified A1E3 and B1C4 contained a clear heavy chain with molecular weight of 88 000 and 52 000 respectively and had the same light chain with molecular weight of 20 000;while Western blotting demonstrated that A1E3 and B1C4 could be recognized by SEA and serum samples of acute schis-tosomiasis cases. The SEA-based ELISA demonstrated the titers of B1C4 and A1E3 were 1∶105 and 1∶30 000,respectively. The serum samples from all the acute cases and 86.9% of the chronic cases showed a positive reaction. All of the control sera from healthy persons gave a negative response. The positive rates of the double monoclonal antibody ELISA and commercial ELISA for detecting the circulating antigen were 45.8%and 43.1%respectively,and there was no significant difference between the results of the two methods. Conclusion A1E3 and B1C4 monoclonal antibody-based ELISA is established successfully. It exhibits a high sensitivity and specificity in detecting circulating antigen of Schistosoma japonicum.

BACKGROUNDTo explore the feasibility of cloning of the hepatocyte receptor interacting with the Pre S1 protein of HBV by two hybrid system.

METHODSYeast expression plasmids encoding fusion proteins of full length or portions of Pre S1 of HBV and DNA binding domain of yeast protein GAL4 were constructed and used to transform yeast reporter strain SFY526. Reporter gene product ?galactosidase activity was assayed as a measure of transcription activation in yeast. Mammalian expression plasmid encoding fusion proteins of full length Pre S1 and DNA binding domain of GAL4 was constructed and used to cotransfect hepatoma cell line Huh?7 together with CAT reporter plasmid. Cell extracts were assayed for CAT activity by thin?layer chromatography.

RESULTSThe fusion proteins of full length Pre S1 protein and GAL4 DNA binding domain present transcriptional activation function in yeast. The transcription activating sequence is localized to the 21 to 47 amino acids of Pre S1 protein Fusion proteins of full length Pre S 1 and GAL 4 DNA binding domain do not show transcriptional activation function in mammalian cells.

CONCLUSIONThe transcriptional activating sequence of HBVPre S1 protein in yeast overlaps the hepatocyte receptor binding site. The transcriptional activation function of HBV Pre S1 protein in yeast may prevent researchers?from using yeast two hybrid system to clone HBV receptor interacting with Pre S1 protein. However, the Pre S1 protein does not show transcriptional activation function in mammalian cells. Mammalian two?hybrid system may be a practical method to clone the HBV hepatocyte receptor interacting with Pre S1 protein.

DNA-Binding Proteins ; genetics ; Fungal Proteins ; genetics ; Hepatitis B Surface Antigens ; genetics ; Humans ; Protein Precursors ; genetics ; Recombinant Fusion Proteins ; genetics ; Transcriptional Activation ; Tumor Cells, Cultured ; Yeasts

Background:Serum pepsinogens (PGs),as a serologic marker for gastric mucosal lesions,can reflect the functional status of gastric mucosa. Helicobacter pylori (Hp)infection can cause pathological changes in gastric mucosa,and has been reported to influence the serum level of PGs. Aims:To explore the influence of Hp infection on diagnostic performance of serum PGs for gastric mucosal lesions. Methods:The endoscopic findings,biopsy pathology (including Giemsa staining) and serum PGs test in 1216 cases of patients from July 2014 to June 2015 at the First Affiliated Hospital of Jiaxing University were collected. Patients were categorized according to the pathological diagnosis and Hp status,and the results of serum PGs test were analyzed between different groups. Results:When patients were classified by gastric mucosal lesion,no significant differences were found in serum levels of PGⅠ,PGⅡ,ratio for PGⅠ/ Ⅱ (PGR)and proportion of PG-positive (PGⅠ≤70 μg/ L and PGR < 3. 0)patients of different mucosal lesion groups with Hp-positive status (P >0. 05),whereas significant differences were observed in serum levels of PGⅠ,PGⅡ,PGR and proportions of patients with PGⅠ≤70 μg/ L or PGR < 3. 0 of different mucosal lesion groups with Hp-negative status (P < 0. 05). When patients were classified by Hp status,PGⅠ level and PGR were lower and PGⅡ level and proportion of PG-positive patients were higher in Hp-positive patients than in Hp-negative patients in any of the gastric mucosal lesion groups (P < 0. 05 in part of the comparisons). Conclusions:Hp infection is strongly associated with the alterations in serum PGs test,which narrows the differences in PGs between groups with different gastric mucosal lesions and expands that within the same mucosal lesion, subsequently decreasing PGR and increasing the proportion of PG-positive patients. Patients negative for Hp infection may need new cut-off value of serum PGs test to improve the sensitivity for diagnosis of gastric mucosal lesion.

Objective:To investigate the correlation between the imaging markers of cerebral small vessel disease (CSVD) and early hematoma expansion (HE) in patients with spontaneous intracerebral hemorrhage (sICH).Methods:Patients with sICH admitted to the Department of Neurology, the Affiliated Hospital of Qingdao University between January 1, 2015 and December 31, 2019 were enrolled retrospectively. All patients received noncontrast CT (NCCT) within 6 h after onset. Within 24 h after the initial NCCT examination, they were reexamed to determine whether HE occurred, and brain MRI examination was completed within 48 h after onset. HE was defined as the increase of hematoma volume on NCCT reexamination by >33% or >6 ml compared with the baseline. NCCT was used to evaluate the abnormal morphology and density signs, including blend sign, swirl sign, black hole sign, island sign, and satellite sign. MRI was used to evaluate CSVD imaging markers, including lacunar infarcts (LIs), enlarged perivascular space (EPVS), white matter hyperintensities (WMHs), cerebral microbleeds (CMBs), and cortical superficial siderosis (CSS). Multivariate logistic regression analysis was used to determine independent risk factors for HE. The receiver operator characteristic (ROC) curve was used to evaluate the predictive ability of imaging markers for HE in patients with sICH. Results:A total of 216 patients with sICH were included. Their age was 57±15 years, 113 (61.6%) were male, 88 (40.7%) had HE, 123 (56.9%) had NCCT signs, 122 (56.5%) had CMBs, 143 (66.2%) had WMHs, 44 (20.4%) had CSS, 25 (11.6%) had LIs, and 31 (14.4%) had EPVS. The baseline hematoma volume, blood calcium, the modified Rankin Scale score and the National Institutes of Health Stroke Scale score at admission, and detection rates of NCCT signs, CMBs, WMHs and CSS in the HE group were significantly higher than those in the non-HE group (all P<0.05). Multivariate logistic regression analysis showed that the blood calcium (odds ratio [ OR] 0.040, 95% confidence interval [ CI] 0.004-0.238; P=0.001), any NCCT signs ( OR 3.275, 95% CI 1.492-7.188; P=0.003), CMBs grade 4 ( OR 3.591, 95% CI 1.146-11.250; P=0.028), CSS ( OR 3.008, 95% CI 1.214-7.452; P=0.017), NCCT signs+ CMBs grade 3 ( OR 3.390, 95% CI 1.035-11.102; P=0.044), NCCT signs+ CMBs grade 4 ( OR 5.473, 95% CI 1.352-22.161; P=0.017), and NCCT signs+ CSS ( OR 3.544, 95% CI 1.215-10.336; P=0.021) were the independent risk factors for HE in patients with sICH. ROC curve analysis showed that the sensitivity of NCCT signs, CMBs and CSS for predicting HE were 81.8%, 64.8% and 34.1%, respectively, and the specificity were 60.2%, 60.9% and 89.1%, respectively. The predictive sensitivity of NCCT signs+ CMBs and NCCT signs+ CSS (59.1% and 30.7%, respectively) was lower than that of single imaging marker, while the specificity (78.1% and 93.7%, respectively) was higher than that of single imaging marker. Conclusions:The imaging markers of CSVD are closely associated with the risk of HE in patients with sICH. Severe CMBs and CSS are the independent risk factors for HE in patients with sICH. The specificity of NCCT signs combined with CSVD imaging markers for predicting HE is increased but the sensitivity decreased.

Objective: To analyze the epidemiological and molecular characteristics of norovirus outbreaks in schools in Xicheng District of Beijing from 2017 to 2022, so as to provide evidence for the prevention and control of norovirus outbreaks in schools. Methods: Data of norovirus outbreaks in schools in Xicheng District, Beijing during 2017 to 2022 were collected and analyzed by descriptive epidemiological methods. Realtime PCR was used to detect the nucleic acid of group GⅠand GⅡnorovirus, the positive norovirus nucleic acid samples were sent to Beijing Center for Disease Control and Prevention for molecular typing. Results: From 2017 to 2022, 185 norovirus outbreaks were reported in schools in Xicheng District, including 166 cluster outbreaks and 19 outbreaks. A total of 2 044 cases were reported, with a total attack rate of 13.92%. There were two peaks in the outbreak time, which were from March to June after the spring semester and from October to December after autumn semester. Primary schools were the most common place of occurrence (101 cases), followed by nursery institutions (68 cases) and secondary schools (16 cases). There were statistically significant differences in the incidence rates among different sites(12.37%, 22.78%, 8.47%, χ2=263.34, P<0.01). There were significant differences in the incidence of vomiting, diarrhea, nausea and stomachache among different students (χ2=263.33, 90.58, 20.42, 30.29, P<0.01). Vomiting was the main symptom in primary school and nursery school children (96.41%, 98.28%), and the diarrhea rate was higher in middle school students (68.22%). The outbreaks were mainly caused by type GⅡ norovirus. The genotype from 2017 to 2021 showed the characteristics of diversity, mainly GⅡ.2[P16], but there was no significant advantage for the GⅡ.2 [P16] during 2019 to 2021. Conclusions The norovirus outbreak in schools in Xicheng district of Beijing from 2017 to 2022 are mainly caused by GⅡ type genome. The main genotype is GⅡ.2[P16]. Norovirus infection mainly occurred in primary schools and kindergartens. For the vulnerable populations, it is necessary to improve the capacity to early identification, student infectious disease management, active infection control and prevention measures, and pathogen surveillance and sporadic case monitoring.

OBJECTIVETo analyze pupils' neglect status aged 6-11 years in China's rural.

METHODSAccording to the principle of multi-stage stratified cluster sampling, to extract 7,943 pupils aged 6-11 years for the survey from 56 primary schools in 28 counties in nine provinces, from December 2012 to March 2013. Proceed questionnaire survey by the scale from "Neglect Evaluation Norms for pupils aged 6-8 years in Rural Areas of China" and "Neglect Evaluation Norms for pupils aged 9-11 years in Rural Areas of China". And analyze neglect rates and neglect degrees of the different grades, gender, family types and different levels of neglect.

RESULTSThe total neglect rate of China's rural pupils aged 6-8 and 9-11 years was 40.2% (1,258/3,130) and 42.5% (1,498/3,526) respectively, which differences had no statistical significant (χ2=3.59, P=0.058); the total neglect degree was 46.04±8.87 and 44.78±10.43 respectively, which differences had statistical significant (t=5.01, P<0.001); the differences of neglect rates and neglect degrees between male (41.4% (657/1,587) and 46.28±8.76) and female (39.0% (601/1,543) and 45.78±8.97) of aged 6-8 were all no statistical significant (χ2=1.87, P=0.171; t=1.49, P=0.136); the neglect rates and neglect degrees of male (46.3% (816/1,763) and 45.53±10.11) were higher than female (38.7% (682/1,763) and 44.06±10.69) in the group of aged 9-11, which differences were all statistical significant (χ2=20.84, t=3.97, P<0.001); the male neglect rate in the group of aged 6-8 in social neglect (11.7% (198/1,691)) and the neglect degree in educational neglect (48.09±9.70) were higher than female (9.4% (155/1,648) and 47.37±9.89), which differences were all statistical significance (χ2=14.55, P<0.001, t=2.22, P=0.026), the male neglect rate in the group of aged 9-11 in physical neglect (20.4% (398/1,954)) was higher than female (16.7% (326/1 957)), which differences had statistical significance (χ2=8.92, P=0.003).

CONCLUSIONThe neglect status of Chinese pupils aged 6-11 years in rural was serious, and we should find out risk factors and provide efficient prevention measures.

Child ; Child Abuse ; China ; Female ; Humans ; Male ; Physical Examination ; Pupil ; Risk Factors ; Rural Population ; Schools ; Surveys and Questionnaires

Tremor is an involuntary and repetitive swinging movement of limb, which can be regarded as a periodic disturbance in tremor suppression system based on functional electrical stimulation (FES). Therefore, using repetitive controller to adjust the level and timing of FES applied to the corresponding muscles, so as to generate the muscle torque opposite to the tremor motion, is a feasible means of tremor suppression. At present, most repetitive control systems based on FES assume that tremor is a fixed single frequency signal, but in fact, tremor may be a multi-frequency signal and the tremor frequency also varies with time. In this paper, the tremor data of intention tremor patients are analyzed from the perspective of frequency, and an adaptive repetitive controller with internal model switching is proposed to suppress tremor signals with different frequencies. Simulation and experimental results show that the proposed adaptive repetitive controller based on parallel multiple internal models and series high-order internal model switching can suppress tremor by up to 84.98% on average, which is a significant improvement compared to the traditional single internal model repetitive controller and filter based feedback controller. Therefore, the adaptive repetitive control method based on FES proposed in this paper can effectively address the issue of wrist intention tremor in patients, and can offer valuable technical support for the rehabilitation of patients with subsequent motor dysfunction.
Humans ; Wrist ; Tremor/therapy* ; Movement ; Computer Simulation ; Electric Stimulation