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【Objective】The light condition is one of the key factors that affect the tissue culture efficiency of Anthurium andraeanum. The effects of different LED light quality ratio and light intensity on different stages of A. andraeanum tissue culture were studied to explore these light conditions suitable for each stage of tissue culture of A. andraeanum and provide an important technical reference for efficient tissue culture of A. andraeanum.【Method】The new A. andraeanum cultivar Fuxing was used as the experimental material, and the effects of different proportions of red and blue LED light ratio and light intensity on callus induction, proliferation culture and strong seedling culture of A. andraeanum Fuxing were analyzed.【Result】The LED red light quality was more suitable for the callus induction of A. andraeanum Fuxing, the 10% R light quality condition with light intensity of 100 lx had the highest callus induction rate of 79.58%, and the callus mass was yellow-green, compact, large in volume and good in state, which was suitable for the callus induction of A. andraeanum Fuxing leaves. The light quality ratio of R ∶ B = 3 ∶ 1 was suitable for callus proliferation culture of A. andraeanum Fuxing, and the proliferation coefficient was the highest (6.44) when the light intensity was 600 lx. Compared with WL light conditions, R ∶ B = 4 ∶ 1 light quality ratio was more suitable for the callus bud differentiation culture of A. andraeanum Fuxing, when the light intensity was 1 000 lx, the number of callus proliferation and differentiation was 19.44, and the buds were short and strong with good growth potential, without yellow leaf phenomenon. The light quality ratio suitable for the tissue culture seedling culture of A. andraeanum Fuxing at the strong seedling stage was R∶B = 4∶1, the light intensity was 900 lx, the number of roots of the strong seedlings of was more, with an average of 5.67, the plant height was 2.88 cm, the stem diameter was 1.44 mm, the leaf length was 11.69 mm, the leaf width was 8.54 mm, the plant leaf was large, the SPAD value was 39.23, the chlorophyll content of the leaf was higher, and the overall growth of the plant was robust without yellow leaf phenomenon.【Conclusion】LED light conditions have an impact on callus induction, proliferation culture, and strong seedling culture of A. andraeanum Fuxing in tissue culture. According to the lighting requirements at different stages of A. andraeanum tissue culture, selecting appropriate LED light quality ratio and light intensity conditions can effectively improve the callus induction rate, proliferation rate and tissue culture seedling production quality of A. andraeanum in tissue culture, and provide technical support for the efficient and standardized production of new A. andraeanum cultivar Fuxing.

【Objective】The study aims to screen out the types, concentrations and application methods of plant growth regulators that can effectively promote early flowering and improve flowering uniformity of Gymnocalycium baldianum, and provide technical support for the regulation of flowering period of G. baldianum.【Method】With uniform seed balls of G. baldianum as test materials, the effects of different concentrations (100, 200, 400 and 800 mg/L) of paclobutrazol, uniconazole, indoleacetic acid and gibberellin on its flowering was explored.【Result】Spraying 100-800 mg/L paclobutrazol, uniconazole and indoleacetic acid solutions had no significant difference in the colour of seed balls, seed ball diameter increment, number of flowers and flowering rate. However, these three plant growth regulators could promote the early flowering of G. baldianum within a appropriate concentration range. The treatment of 100 mg/L paclobutrazol had the best result, which bloomed about 9.0 days earlier than that under water treatment. It could reach the full blooming period within 11.7 days, which was about 20.0 days shorter than that under water treatment, and the flowering had better uniformity. While the 100-800 mg/L gibberellin solution had an inhibitory effect on the flowering of G. baldianum, however, it could promote vegetative growth. The ball size, the number of thorns in the thorn seat, the thorn length, and the mass of the thorn seat all increased, and the colour of the seed ball was greener.【Conclusion】The study results can provide technological support for promoting the early flowering of G. baldianum and improving the uniformity of flowering. At the same time, it can improve the ornamental characters of G. baldianum according to individual needs, and improve its ornamental value, which has great significance to increase market share furtherly.

【Objective】Tissue culture is one of the important ways for rapid propagation of Aglaonema commutatum, the factors affecting leaf color in tissue culture were studied and explored to maintain the redness of leaf color, and to provide technical references for further stabilizing efficient tissue culture technology and regulating leaf color of A. commutatum with red leaves.【Method】Taking A. commutatum 'Guanghuahong' with red leaves as experimental material, the effects of proliferation medium, proliferation mode, light intensity and light quality on leaf color of A. commutatum were studied.【Result】The improved MS medium supplemented with 0.5 g/L K2SO4 was used for proliferation culture, and the proliferation and differentiation seedlings were more robust, with brighter leaf color, and the transplanting seedling rate was 90.00%.The leaf color of tissue culture seedlings cultured by the proliferation of clustered buds was more stable than that cultured by the proliferation of callus, and the transplanting seedling rate was higher. In the stages of proliferation and rooting, when the light intensity was 4 000 lx, the red plaque area increased, and the transplanting seedling rate was higher (88.89%). Under the light quality condition of red light : blue light = 3∶7, the lowest total content of chlorophyll in leaves was 0.037 mg/g, and the highest relative content of anthocyanin was 0.399 Units/g, and the leaves were red and brilliant.【Conclusion】Using the improved proliferation medium, adopting the proliferation mode of clustered buds, adjusting the light intensity and changing the red and blue light quality ratio can effectively maintain the redness of leaves and improve the production efficiency of tissue culture.

Objective: To analyze the characteristics of sleep structure and its correlation with cognitive impairment in early Alzheimer’s disease(AD) patients by assessing cognitive function and polysomnography. Methods: Eighty-eight elderly patients who underwent polysomnography were retrospectively analyzed and enrolled. According to the presence or absence of cognitive impairment, 39 patients were in the control group with a total score of montreal cognitive assessment (MoCA) score more than or equal to 26, 49 patients were in the AD group, with a total MoCA score less than 26 and a clinical dementia rating scale (CDR) score=0.5. Pearson correlation analysis and Spearman rank correlation analysis were used to explore the sleep structure characteristics of the early AD patients and its correlation with cognitive impairment. Results: Compared with the control group, the early AD group had statistically significant differences in MoCA, CDR, Hamilton Depression Scale (HAMD), micro perception index, non-rapid eye movement(NREM)/total sleep time (TST)%, N4 stage (N4)/TST% and REM /TST% (P

Background The risks of diabetic retinopathy and carotid atherosclerosis (CAS) may be increased in diabetics with poor glycemic control, and CAS is a risk factor for both coronary heart disease and stroke. Understanding the relationship between diabetic retinopathy and CAS may offer insights into the development of new clinical decision-making strategies for improving diabetic complications. Objective To assess the correlation between CAS and proliferative diabetic retinopathy (PDR) in patients with type 2 diabetes mellitus (T2DM) with a long duration of diabetes and poor glycemic control. Methods A retrospective, case-control design was adopted. One hundred and fifty-eight T2DM patients〔glycosylated hemoglobin (HbA1c) ≥7.5%, glomerular filtration rate (eGFR) ≥60 ml·min-1· (1.73 m2) -1, and diabetes duration≥10 years; 53 with PDR, and other 105 without; 48 with normal carotid arteries and other 110 with CAS〕 were consecutively recruited from Department of Endocrinology, Beijing Tongren Hospital, CMU, from October 2014 to November 2015. Clinical characteristics and laboratory indices were recorded. Results Compared with patients without diabetic retinopathy, those with PDR had higher systolic blood pressure, 24-hour urinary microalbumin excretion rate, and resting heart rate, as well as lower eGFR (P

Background and purpose: N-Myc down stream-regulated gene 2 (NDRG2) is a new type of tumor suppressor gene, which plays an important role in cell proliferation and apoptosis. The chemotherapy resistance of bladder cancer is the main cause for the failure of clinical treatment; therefore, this study aimed to clarify the expression of NDRG2 and its potential role in the pathogenesis of cisplatin (CDDP) resistance in bladder cancer cells. Methods: Bladder cancer T24 cells were continuously passaged by increasing the CDDP concentration for 6 months to obtain CDDP-resistant T24/CR cell lines. Lentiviral transfection was used to achieve high expression of NDRG2 in T24/CR. Cell viability was measured by MTT, apoptosis and transwell invasion assay were performed. The effect of NDRG2 overexpression on T24 cell resistance to CDDP was compared. Bcl-2-siRNA transient transfection was used to knock down the expression of NDRG2 in T24 cells, and then the expression in different groups was detected by Western blot. Real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) was used to detect the expression level of NDRG2 mRNA. Results: The expression level of NDRG2 was significantly down-regulated in CDDP-resistant bladder cancer cells. Exogenous overexpression of NDRG2 enhanced the sensitivity to CDDP and inhibited the viability and invasion of bladder cancer cells in the presence of CDDP. Knockdown of NDRG2 expression had no significant effect on the expression of Bcl-2. Knockdown of Bcl-2 could effectively eliminate the effect of low NDRG2 expression on the viability and apoptosis of bladder cancer cells, and could restore the sensitivity to CDDP in bladder cancer cells. Conclusion: The unbalance of NDRG2/Bcl-2 maybe the key mechanism of CDDP resistance in advanced bladder cancer. Enhanced expression of NDRG2 might be used as a candidate for the treatment of CDDP-resistant or refractory bladder cancer.