Aim To discover specific telomerase inhibitors by high-throughput screening in the more than 2 000 strains of actinomycetes fermentation broth.Methods After verifying the three kinds of screening models for telomerase inhibitor by yeast PCR,the three yeast strains were inoculated overnight into yeast liquid culture which was lacking in histidine and contained 3-AT.Then concentration of yeast strains in culture liquid and dosage of screening sample were regulated for better adjustment to the high-throughput screening.At last the adjusted liquid culture containing yeast strain piped to 96-well plates,drug samples and control article were also added,then the yeast was incubated in the thermostat oscillator.At the same time OD_(595nm) of the yeast liquid was measured every 12 h by using Multifunctional Microplate Analyzer,and the samples whose inhibitory efficiency was over 0.45 were selected for secondary screening.Results The high-throughput screening method related to yeast three-hybrid system was effective in screening samples that had potential telomerase inhibitory ability.The initial concentration of yeast liquid OD_(595nm) was 0.04 and the best dosage of samples was 5 ml.14 active samples,whose inhibitory efficiency was over 0.45,were founded after primary and secondary screening.Conclusions High-throughput screening method related to yeast three-hybrid system is simple and stable in discovering telomerase inhibitors,and 14 new antitumor compounds are identified,which lays the foundation in the development of new anti-tumor agents.

OBJECTIVETo describe the distribution of plasma folate concentrations and prevalence of folate deficiency in adults aged 35 to 64 years in some areas and different seasons in China.

METHODSStudy subjects were sampled from the representative rural and urban areas in the south and north of China aged 35 to 64 years totaling 2 545, and their plasma folate concentrations were determined and analyzed.

RESULTSPlasma concentrations of folate in the southern population were significantly higher (16.9 nmol/L) than those in the north (8.3 nmol/L), and the prevalence of folate deficiency in the south (5.8%) was significantly lower than that in the north (37.1%). Plasma folate concentration varied with season either in the south or north. Plasma concentrations of folate were lower during the summer and the fall (15.0 nmol/L) than those during the winter and the spring (18.8 nmol/L) in the south, but without significant changes in the prevalence of folate deficiency in different seasons. However, the plasma folate concentrations were significantly higher during the summer and the fall (9.7 nmol/L) than those during the winter and the spring (7.1 nmol/L) in the north. And the prevalence of folate deficiency in the north was significantly higher in winter and spring (48.0%) than that in summer and fall (26.2%).

CONCLUSIONSThere existed significant difference in plasma folate concentrations in adults between varied geographic areas in China, which differed from their seasonal changes.

Adult ; China ; epidemiology ; Female ; Folic Acid ; blood ; Folic Acid Deficiency ; epidemiology ; Humans ; Male ; Middle Aged ; Rural Health ; statistics & numerical data ; Seasons ; Urban Health ; statistics & numerical data

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with quick disease progression and poor prognosis. The pathogenesis is extremely complex, involving genetic mutations, abnormal activation of signal pathways, and epigenetic changes. Autophagy is a basic physiological phenomenon of maintaining internal environment stability and promoting cell survival when cell stress occurs, which plays an important role in the occurrence, development and prognosis of various tumors including HCC. Autophagy can participate in the formation and progress of HCC through the above molecular mechanisms. This paper reviews the progress of relationship between autophagy and HCC.

Objective:To study the effectiveness of noninvasive embryo chromosome screening (NICS) based on blastocyst culture medium and cystic fluid in preimplantation genetic detection (PGT) of embryos in different age groups.Methods:A retrospective analysis of 62 couples who underwent PGT assisted pregnancy in Shenzhen Hospital of Peking University from January 2019 to June 2021. A total of 310 blastocysts were biopsied. At the same time, D3-6 blastocyst culture medium and blastocyst cavity fluid were collected for NICS. According to the age of the patients, they were divided into three groups: <35 years old group, 35≤age<40 years old group and ≥40 years old group. The results of NICS were compared with those of embryonic trophoblast (TE) biopsy in each group, and the consistency, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Then the consistency, sensitivity, specificity, positive predictive value and negative predictive value of NICS and TE among the three age groups were statistically analyzed.Results:There was no statistically significant difference in the consistency rate of NICS and TE among the three age groups ( P>0.05), but there was an upward trend in the elderly group (35≤age<40 years and ≥40 years). There was no statistically significant difference in specificity, sensitivity and PPV among the three age groups ( P>0.05). There was significant difference in NPV between the ≥40 years group and the other two groups ( P<0.05). Conclusions:There was no statistical difference in the effectiveness of NICS among different age groups, However, there was an increasing trend in people ≥35 years of age.