OBJECTIVEThis research aimed to study the inhibitory effect of xylitol on the growth and acid production of Actinomyces viscosus (A. viscosus).

METHODSWe cultivated A. viscosus in anaerobic conditions with different concentrations (128, 64, 32, 16, 8, and 4 g x L(-1)) of xylitol brain heart infusion liquid medium and determined the minimum inhibitory concentration (MIC). Subsequently, we measured the pH value of the control group, as well as those of 1/2, 1/4, 1/8 MIC, and MIC concentration groups at 1.5, 3, 6, 12, 24, and 48 h. The Delta pH and OD550 at 2, 4, 6, 8, 10, and 12 h were calculated. We discovered that the minimum xylitol concentrations suppressed 50% and 90% A. viscosus biofilm formation (i.e., MBIC50 and MBIC90). SPSS 19.0 was used to analyze the collected data, and conclusions were drawn afterward.

RESULTSXylitol inhibited the growth ofA. viscosus at MIC of 64 g x L(-1). After 12 h, the differences of pH value among groups were all statistically significant (P < 0.05), and Delta pH increased when the MIC concentration decreased. Except for the 1/2 MIC and MIC groups, the differences of OD550 among groups had no statistical significance (P>0.05), and OD550 also increased when the MIC concentration decreased. These results imply that the ability ofA. viscosus to grow and produce acid in 1/2 MIC and MIC conditions will be reduced with the increase in xylitol concentration. The value of MIBC50 was 64 g x L(-1), whereas the value of MIBC90 was 128 g x L(-1). This finding indicates that the xylitol medium can restrict A. viscosus biofilm formation.

CONCLUSIONXylitolcan effectively inhibit the growth, adhesion, and acid production ofA. viscosus, protecting teeth from cariogenic bacteria and preventing caries to a certain extent.

Actinomyces viscosus ; Bacteria ; Dental Caries ; Humans ; In Vitro Techniques ; Xylitol

Objective To investigate the median effective plasma target concentration of propo-fol (Cp50 )needed for lumbar surgery during inhalation-intravenous balanced anesthesia when BIS is 50.Methods Patients aged 40-56 years,scheduled for vertebral pulp ectomy were included.Anesthe-sia were maintained by TCI of propofol,sevoflurane 0.5 MAC,remifentanyl 0.2 μg·kg-1 ·min-1 , and vecuronium 0.08 mg·kg-1 ·h-1 .The target plasma concentration of propofol was initially set at 1.8 μg/ml,and adjusted by the sequential up-and-down methods,based on BIS index.The Cp50 of propofol and its 95% confidence interval (CI)were calculated.Results Twenty-six patients were en-rolled in this study.The median effective plasma target concentration of propofol was 1.61 μg/ml (95%CI 1.52-1.70)μg/ml.Conclusion The Cp50 of propofol needed for maintaining the BIS index of 50 is 1.61 μg/ml during the anesthesia with 0.5 MAC of sevoflurane combined with remifentanyl in lumbar surgery.

Cause of Death ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; mortality ; Humans ; Infant ; Male

Objective To find out some trigger factors for the onset of acute childhood leukemia by examining seasonal distribution through a small cohort study in a single center.Methods The records of 688 childhood patients(age≤15 years)whom were initially diagnosed at Blood Disease Hospital of CAMS from October 2003 to June 2006,were retrospectively analyzed.Results In terms of time,our study provides modest support for sessonal peaks in summer and winter,or in Jan & Jun.Conclusion We initially realized the season tendency of the onset of acute childhood leukemia in some northern parts of China.which suggest that childhood acute leukemia is associated with the infection.

OBJECTIVETo study chemical constituents contained in Desmodium caudatum.

METHODThe chemical compounds were separated by using such chromatographic methods as macroporous resin, Sephadex LH-20, ODS and normal phase silicagel column, and their structures were identified by spectroscopic data analysis.

RESULTFifteen compounds were separated and identified as stigmasterol (1), beta-sitosterol (2), citrusinol (3), hibiscone A (4), yukovanol (5), kenusanone I (6), neophellamuretin (7), desmodol (8), erythrotriol (9), hibiscone D (10), kaempferol (11), 8-prenylquercetin (12), leachianone G (13), 5,7,4'-trihydroxy-dihydroflavonol (14), and 4H-1-benzopyran-4-one, 2-(3,4-dihydroxyphenyl) -2, 3-dihydro-3,5,7-trihydroxy-8-( 3-methyl-2-butenyl) -, (2R-trans)-(9CI) (15).

CONCLUSIONAll of the compounds were separated from D. caudatum for the first time except compound 8.

Drugs, Chinese Herbal ; chemistry ; Fabaceae ; chemistry ; Organic Chemicals ; analysis ; isolation & purification ; Spectrum Analysis

Objective To analyze the staff structure, turnover and income of human resources in disease control and prevention institutions(CDCs)at different levels in China, to identify the existing problems, and to make policy recommendations accordingly. Methods A questionnaire survey was used to collect the data on the staff of CDCs at different levels in China from 2016 to 2018. Descriptive analysis and trend analysis were conducted on the number of staff, recruitment and turnover, income and other indicators in the three years. Results A total of 606 CDCs were included in the study. The proportion of job openings was 11.97% in 2018. Although the median proportion of professional personnel and health professional personnel in the CDCs reached the national standard(85% and 70%, respectively), a considerable number of institutions failed to meet the national standard. From 2016 to 2018, staff turnover in the CDCs has been increasing, with a minimum of 0.73(in 2016, municipal CDCs)and a maximum of 10.52(in 2018, provincial CDCs). In the staff who quit the CDCs, the proportion of junior professionals was the highest, while that of medium and senior professional increased gradually. Of them, the proportion of staff with graduate education in eastern China and provincial CDCs was higher than that of undergraduate education, while the proportion of staff with graduation education in other regions also increased. From 2016 to 2018, the average annual income in the CDCs in most regions did not reach the national average wage level of urban employees in health, social security and social welfare field in the same period. In county and district level CDCs in central and western China, personal income in 2018 was even less than the national average wage level in 2016. Conclusion Human resources in the CDCs at different levels in China remains insufficient and unbalanced, which warrants a"supporting policy"mechanism for public health personnel. The loss of the personnel in the CDCs continues to increase, in which the loss of senior professionals become increasingly serious. It raises a new concern to establish and improve the incentive mechanism of public health personnel. Furthermore, personal income in the CDCs is lower than the local average level. It is necessary to set personal income reasonably according to local economic level.

OBJECTIVE: To study the efficacy and safety of vitamin D as an adjuvant therapy for childhood pneumonia through a systematic review. METHODS: Cochrane Library, PubMed, EMbase, CNKI, Wanfang Data, and Weipu Data were searched for randomized controlled trials (RCTs) of vitamin D as the adjuvant therapy for childhood pneumonia published up to August 2019. Literature screening, quality assessment, and data extraction were performed based on inclusion and exclusion criteria. Revman 5.3 was used to perform the Meta analysis of outcome indicators. RESULTS: A total of 7 RCTs with 1 527 children were included, with 762 children in the vitamin D adjuvant therapy group and 765 children in the control group. The results of the Meta analysis showed that vitamin D adjuvant therapy had no effect on recovery time (P=0.67), length of hospital stay (P=0.73), and time to relief of fever (P=0.43). Furthermore, it did not reduce the recurrence rate (P=0.14), rate of adverse events (P=0.20), and mortality rate (P=0.98) of childhood pneumonia. CONCLUSIONS Current evidence shows that vitamin D adjuvant therapy has no marked efficacy in the treatment of childhood pneumonia.

Amino Acid Sequence ; Amyloid beta-Peptides ; genetics ; immunology ; Enzyme-Linked Immunosorbent Assay ; Epitope Mapping ; Epitopes ; genetics ; immunology ; Humans ; Immunoglobulin Fragments ; genetics ; immunology ; Immunoglobulin Variable Region ; genetics ; immunology ; Molecular Sequence Data ; Peptide Library ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

OBJECTIVETo establish a method to detect Down's syndrome through quantitative pyrosequencing of the heterozygous single nucleotide polymorphisms (SNPs) on the chromosome 21.

METHODSAn improved allele-specific-amplification was used to screen heterozygous SNPs on the chromosome 21 from 84 normal samples. Pyrosequencing was used to quantitatively determine the ratio between the two alleles of a heterozygote, and the diagnosis of Down's syndrome was thus carried out based on the ratio.

RESULTSBy genotyping 84 genomic DNA samples from normal Chinese population, 6 SNPs with a relatively high level of heterozygosity were screened out. Heterozygote coverage of 92.9% was achieved by using a panel of 6 SNPs on the chromosome 21. Ten clinical samples from Down's syndrome patients were quantitatively determined by pyrosequencing, and 9 samples were accurately diagnosed by comparing the ratio of the two alleles. The pyrosequencing results showed that the ratio of the two alleles were 2:1 or 1:2 for the Down's syndrome patients.

CONCLUSIONThe method has the advantage of a low cost, simple process, and time-saving operation and could be potentially applicable to the rapid diagnosis of Down's syndrome.

Alleles ; Asian Continental Ancestry Group ; genetics ; Chromosomes, Human, Pair 21 ; Cloning, Molecular ; DNA ; analysis ; Down Syndrome ; diagnosis ; genetics ; Female ; Genetic Testing ; Humans ; Karyotyping ; methods ; Polymorphism, Single Nucleotide ; genetics ; Pregnancy ; Prenatal Diagnosis ; economics ; methods