Objective To establish three methods of DNA extraction from Cryptosporidium parvum oocysts and test by PCR. Methods After three freeze-thaw cycles, three kinds of templates were extracted from the oocysts by Chelex-100, phenol/chloroform or genomic DNA purification system kit, and used for PCR detection. According to the sequence of a C.parvum gene (L16996), a pair of primers was designed and synthesized, and used for PCR. The sensitivity of the template by Chelex-100 method was also tested by PCR. Results One 446 bp PCR product was observed by agarose gel electrophoresis for all three kinds of templates. The PCR sensitivity by Chelex-100 extracted DNA reached for detection of a specimen containing only 1/2 oocyst. Conclusion The three kinds of extraction can all be served as templates for PCR detection of C.parvum oocysts, while Chelex-100 method is simpler, quicker and more reliable for DNA extraction of the parasite.

Objective To investigate the protective immunity of the recombinant thioredoxin of Schistosoma japonicum(reSjcTrx)in mice. Methods Thirty 6-week old female C57BL/6 mice were randomly divided into 3 groups with 10 each: reSjcTrx with Montanide ISA720 adjuvant, adjuvant control, and infection control. Mice were vaccinated subcutaneously at week 0, 2, 4 with reSjcTrx emulsified in Montanide ISA720 adjuvant. The mice in adjuvant group was injected three times with Montanide ISA720 and saline only. Mice in infection control group were given no injection. Three weeks after final injection, each mouse was challenged with 30?1 cercariae of S. japonicum (Chinese strain). At the week six after challenge, all mice were sacrificed and perfused. The number of recovered worms and eggs from liver tissue of mice were counted. Sera were collected from mice before immunization, before challenge and before killing. The anti-SjcTrx antibodies in sera were detected with ELISA. Results ELISA showed a high level of specific IgG antibodies in mice immunized with the reSjcTrx. The worm reduction rate and egg reduction rate of reSjcTrx immunization group were 22.8% and 29.5% respectively, significantly higher than those of the control groups (P﹤0.05). SDS-PAGE and Western blotting revealed that the molecular weight of expressed protein was around Mr 14 000 and could be recognized by sera from rabbit infected with S.japonicum and from mice immunized with reSjcTrx. Conclusion The reSjcTrx induces certain protective immunity against schistosomiasis japonica in mice.

Objective To isolate and identify Cryptosporidium oocysts from feces of naturally infected cow. Methods Fecal samples were collected from Cryptosporidium infected cows confirmed by modified acid-fast staining method. Oocysts were isolated and purified with Sheather sucrose density gradient centrifugation technique. Genomic DNA was isolated with Chelex-100. Both primers were designed to amplify Cryptosporidium small subunit ribosome RNA gene (SSU rRNA) and Cryptosporidium oocyst wall protein gene (COWP), respectively. The PCR products were cloned into pGEM-T and pGEM-T Easy vector and sequenced subsequently. Homology and phylogeny were analyzed with BLASTn and MEGA software. Results The results suggested that the size of oocysts was (7.4?0.32)?m by(5.4?0.21)?m and the ratio of length and width was 1.37?0.07 (n=20). BLASTn revealed that the identity of SSU rRNA and COWP gene of Cryptosporidium isolated from cow to the counterparts of C.andersoni was 100% and 99% respectively. Phylogenetic reconstruction placed the isolated Cryptosporidium within the C.andersoni clade based on the sequence of SSU rRNA and COWP gene. Conclusion What isolated from naturally infected cow feces has been identified as C. andersoni.

Objective: To construct and determine the weight of Index System for Assessing Parent s Ability on Child Injury Prevention, and to provide the basis for childhood injury intervention in family. Methods: Twenty four experts majored in related fields were invited to participate in Delphi consultation. The final index system was constructed according to the consulting results and the weight of primary and secondary indicators were calculated. Results: The final index system consisted of 5 subscales corresponding to 5 age groups: 0,1-2,3-5,6-11 and 12-17 years old. Each scale included 4 primary indicators and 11 secondary indicators. The weight of primary indicators obtained by analytic hierarchy process is 0.28 for "environment", 0.16 for "product", 0.31 for "behaviors and skills", and 0.25 for "psychology". The highest weight of secondary indicators for "environment", "product" and "behaviors and skills" was "water area", while the top secondary indicators for "psychology" included "parental style""emotional control" "family atmosphere", with all indicators weighted higher than 0.2. Conclusion The Index System for Assessing Parent s Ability on Child Injury Prevention by Delphi consultation is comprehensive in content, and with the focus on parental behaviors and skills on injury prevention.

Objective: To investigate child injury prevention practice and associated factors among parents of primary school students. Methods: Parents of 2 577 students were selected from three primary schools in three administrative regions of Shanghai by multi stage sampling method between May and June in 2021. Questionnaire survey was administered to parents based on the Index System for Assessing Parent s Ability on Child Injury Prevention, which was developed previously by the present research group. Results were converted into standardized scores for descriptive analysis, and the original scores were analyzed by multiple linear regression model. Results: The standardized scores of parents on environment safety, product safety, behaviors and skills and psychological safety were (0.91±0.08)(0.93±0.08)(0.97±0.04)(0.95±0.05), respectively. The standardized score of general ability was (0.95±0.04). The standardized scores on knowledge, attitude and practice of injury prevention were (0.99±0.03)( 0.97± 0.05)(0.89±0.10), respectively. Mothers performances were generally better than fathers . Parents with higher education performed better than those with lower education. Parents with "being a parent" in mind performed better on child injury prevention. Conclusion There is a gap between practice with the knowledge as well as attitude towards child injury prevention among parents of primary school students. Parenting role, educational background and parental awareness of the importance of parental role are primary factors that affect child injury prevention practice.

Objective: Develop a nutrition health educational guidance outline for primary and secondary school students which is adapted to the characteristics of Shanghai and meets the cognitive level of students at different levels, so as to provide a reference for planning the content and target of nutrition health education among students of different school stages. Methods: Through literature search and qualitative interviews, the framework of nutrition health education for primary and secondary school students in Shanghai was developed, and 21 experts in the fields of nutrition, school health and health education were invitied to conduct a Delphi consultation, and determined the content of nutrition and health education for students in each school section based on the consultation results. Results: The recall rate for both rounds of consultation was 100%, the degree of expert authority was 0.74 and 0.89 , and the coordination coefficients were 0.31 and 0.33( P <0.01), suggesting high credibility of expert opinion. The resulting guidance outline included 2 first level entries, 6 second level entries, 60 third level entries and corresponding entry explanations. The 2 first level entries were rational nutrition and food safety; the 6 second level entries were food and nutrients, balanced diet, good eating habits, nutritional practices, good hygiene habits and food borne diseases; the 60 third level entries needed to be studied in Level 1 were 24, Level 2 were 41, Level 3 were 55, and Level 4 were 59. Conclusion The nutrition health educational guidance outline for primary and secondary school students in Shanghai developed in this study focuses on key nutrition knowledge, rational dietary behaviors and nutrition practice skills, which can provide a reference and basis for the phased implementation of nutrition health education in primary and secondary schools.

Biomineralization is the process by which organisms form mineralized tissues with hierarchical structures and excellent properties, including the bones and teeth in vertebrates. The underlying mechanisms and pathways of biomineralization provide inspiration for designing and constructing materials to repair hard tissues. In particular, the formation processes of minerals can be partly replicated by utilizing bioinspired artificial materials to mimic the functions of biomolecules or stabilize intermediate mineral phases involved in biomineralization. Here, we review recent advances in biomineralization-inspired materials developed for hard tissue repair. Biomineralization-inspired materials are categorized into different types based on their specific applications, which include bone repair, dentin remineralization, and enamel remineralization. Finally, the advantages and limitations of these materials are summarized, and several perspectives on future directions are discussed.
Biomineralization

Five new saponins, including three steroid saponins, paristenoids A-C (1-3), and two triterpenoid saponins, paristenoids D-E (4-5), along with four known ones (6-9) were isolated from the rhizomes of Paris polyphylla var. stenophylla. The structures of the isolated compounds were identified mainly by detailed spectroscopic analysis, including extensive 1D and 2D NMR, MS, as well as chemical methods. Compound 3 is a new cyclocholestanol-type steroidal saponin with a rare 6/6/6/5/5 fused-rings cholestanol skeleton, and this skeleton has been first found from the genus Paris. The cytotoxicities of the isolated compounds against three human three glioma cell lines (U87MG, U251MG and SHG44) were evaluated, and compound 7 displayed certain inhibitory effect with IC₅₀ values of 15.22 ± 1.73, 18.87 ± 1.81 and 17.64 ± 1.69 μmol·L^-1, respectively.
Humans ; Rhizome/chemistry* ; Steroids/chemistry* ; Liliaceae/chemistry* ; Saponins/chemistry* ; Triterpenes/analysis*

ObjectiveTo investigate the demographic characteristics， high-risk behavior and first CD4⁺T cell（CD4 cell） counts among newly reported HIV-infected Burmese in Dehong Dai Jingpo Autonomous Prefecture （Dehong Prefecture） from 2019 to 2020. MethodsA cross-sectional survey was conducted among newly reported HIV-infected Burmese cases in Dehong Prefecture from 2019 to 2020 to collect related information and measure their first CD4 cell counts. ResultsAmong 1 228 HIV-infected Burmese cases， 846 （68.9%） were males and 382 （31.1%） were females； 445 （36.2%） were from Kachin， and 210（17.1%） were from Shan. Of them， 960 cases （78.2%） had participated in the first CD4 cell counts testing， and 405 cases （42.2%） had a first CD4 cell counts <350 cells·μL^-1. In the multivariable logistic regression analysis， age ≥30 years （adjusted OR=1.44， 95%CI： 1.07‒1.92） and history of illicit drug use in Myanmar （adjusted OR=0.41， 95%CI： 0.21‒0.79） were independently associated with first CD4 cell counts <350 cells·μL^-1. ConclusionThe first CD4 cell counts are generally low among newly reported HIV-infected Burmese in Dehong Prefecture， especially those aged ≥ 30 years and with a history of intravenous drug use in Myanmar. Therefore， early detection of HIV infection should be strengthened for timely intervention and treatment management among Burmese.

ObjectiveTo determine the characteristics， viral load and immunological status of HIV-infected persons and their spouses who became HIV-positive， and the reasons for HIV seroconversion in 55 HIV discordant couples in Dehong Dai and Jingpo Autonomous Prefecture （Dehong Prefecture）， Yunan Province. MethodsData on the 55 couples meeting the criteria of having a previously positive spouse were retrieved from the AIDS Integrated Prevention and Control Data Information System of the China Disease Control and Prevention Information System during 2015-2021. General socio-demographic information， age at diagnosis， exposure history， CD4⁺T lymphocyte count， and antiviral treatment were collected. Descriptive analysis and chi-square test were used to compare the distribution of pre-HIV-positive spouses and their HIV seroconverted spouses. ResultsA total of 55 spouses from HIV discordant couples had HIV seroconversion. Of them， 72.7% （40/55） of pre-HIV-positive spouses were husbands. The most recent CD4⁺T lymphocyte count in the pre-HIV-positive spouses was （328.31±246.27） cells·μL^-1 at the time of diagnosis of their seroconverted spouses， of which 36.3% （20/55） had a CD4⁺T lymphocyte count of less than 200 cells·μL^-1. Furthermore， of those pre-HIV-positive spouses with low CD4⁺T lymphocyte count， 45.0% （9/20） had an undetectable viral load， 15.0% （3/20） <400 copies·mL^-1， and 25.0%（5/20） ≥400 copies·mL^-1. Additionally， 16.4% （9/55） of the pre-HIV-positive spouses did not have a viral load test. The main reasons for HIV seroconversion among HIV-negative spouses in the discordant couples were poor condom use， poor compliance with antiviral therapy， and treatment discontinuation. ConclusionThe follow-up management of HIV discordant couples should be strengthened in Dehong Prefecture， especially the monitoring of viral load levels and immunological status of pre-HIV-positive spouses， to improve their compliance with antiviral therapy and reduce treatment discontinuation， which would effectively prevent and control HIV transmission between spouses.