Effects of exogenous melatonin on photosynthesis and physiological characteristics of chry-santhemum seedlings under high temperature stress

We examined the effects of exogenous melatonin (MT) on the resistance of Chrysanthemum morifolium 'Jinba' to high temperature stress. Chrysanthemum leaves were sprayed with 200 μmol·L^-1MT, and then subjected to high temperature stress at 40 ℃ (day)/ 35 ℃ (night). The ultrastructure of chloroplast and thylakoid of chrysanthemum leaves were observed, and the photosynthetic and physiological indices were measured. The results showed that the chloroplast and thyla-koid structures of chrysanthemum were damaged under high temperature stress. The chlorophyll contents and maximum fluorescence (F_m) were significantly reduced, while the OJIP curve changed with the fluorescence of K and J points increased. The net photosynthetic rate (P_n), transpiration rate (T_r) and stomatal conductance (g_s) were significantly decreased, while the internal CO₂ concentration (C_i) was significantly increased. The relative conductivity (REC), malondialdehyde (MDA), reactive oxygen species (ROS), osmotic adjustment substances content and antioxidant enzyme activity all increased significantly. Spraying exogenous MT onto leaves could maintain the integrity of chloroplast and thylakoid structure under high temperature in chrysanthemum and significantly decrease the increment in the K and J points of OJIP curve. Exogenous application of MT alleviated the inhibition of high temperature stress on photosynthesis and fluorescence of chrysanthemum, as indicated by significantly higher F_m, P_n, g_s, T_r and photosynthetic pigment contents and lower C_i. Exogenous MT also significantly reduced the REC, MDA and ROS contents of chrysanthemum under high temperature stress, and enhanced the osmotic adjustment substances content and antioxidant enzyme activity in chrysanthemum leaves. It suggested that exogenous MT could protect the integrity of chloroplast structure of chrysanthemum leaves, enhance photosynthesis, inhibit the excessive production of ROS in the plants under high temperature stress, improve the activity of antioxidant enzyme system, reduce the level of membrane peroxidation and keep the integrity of lipid membrane, and thus improve the ability of chrysanthemum plants to resist high temperature stress.

[A cross-sectional study on psychological needs of family members of critically ill inpatients in semi-closed wards and analysis of influence factors]

Objective: To analyze and discuss the psychological needs of family members of critically ill burn inpatients in semi-closed wards and their related influence factors. Methods: A cross-sectional survey was conducted among the 82 burn patients, who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of Ruijin Hospital of Shanghai Jiao Tong University School of Medicine from October 2018 to April 2019, and their family members. A general condition questionnaire of 15 indexes was applied to investigate the general data of burn patients and their family members including cause of burn, gender, age, total burn area, burn depth, burn severity, burn site, and type of medical insurance of patients, kinship with the patients, gender, age, experience of accompanying in intensive care isolation wards, occupation, education level, and monthly income of their family members. The Critical Care Family Needs Inventory (CCFNI) was used to assess each item, each factor, and total scores of the family members of patients including 5 factors and 45 items such as support scale (SS), comfort scale (CS), information scale (IS), proximity scale (PS), assurance scale (AS). CCFNI was used to assess the total scores of patients and their family members after classification according to the general data, the data were statistically analyzed with one-way analysis of variance or independent sample t test. Indicators with statistical significance in the above analysis were selected for multiple linear regression analysis to screen the independent influence factors of psychological needs of patients' family members. CCFNI was used to assess each dimension scores of patients and their family members after classification according to the aforementioned selected independent influence factors including age and burn area of patients, gender, educational level, and experience of accompanying in intensive care isolation wards of their family members, and the data were statistically analyzed with one-way analysis of variance or independent sample t test. Results: A total of 82 questionnaires were sent out in this study, and 80 were effectively received, with s a recovery rate of 97.6%. In 80 patients, there were 45 males and 35 females; 35 cases (43.75%) were ≤14 years; most of the patients had flame and thermal burns; 33 patients (41.25%), 21 patients (26.25%), and 26 patients (32.50%) had moderate, severe, and extremely severe burns, respectively; and only 3 patients (3.75%) had no health insurance. In 80 family members of patients, 34 (42.50%) were males and 46 (57.50%) were females; 62.50% in the family members of patients were concentrated between 18 and 45 years old; and 12 family members of patients had experience of accompanying in intensive care isolation wards, accounting for 15.00%. The total CCFNI score of the family members was (141±14) points, and the scores of AS, PS, IS, CS, and SS were (3.77±0.23), (3.43±0.37), (3.53±0.34), (2.50±0.59), and (2.69±0.45) points, respectively. The top five items of the psychological needs of family members of patients were concentrated in three factors (AS, PS, and IS), and the item "ensuring that patients receive the best treatment" ranked the first, with a score of (3.99±0.11) points. There were significant differences on the CCFNI total scores of patients with different age, total burns area, and severity of burns and of their family members with different gender, education level, and whether or not experience of accompanying in intensive care isolation unit (F=4.378, 5.481, 5.913, t=4.027, 14.339, 7.265, P<0.05 or P<0.01). Multiple linear regression analysis showed that the patient's age (≤14, 15-45 years) and total burn area (11%-30%, 31%-49%, ≥50% TBSA) and the patient's family members' gender, educational level, experience of accompanying in intensive care isolation unit could affect the psychological needs of family members of patients (t=3.133, 2.260, 2.297, 2.433, 3.015, 2.200, 2.102, 2.463, P<0.05 or P<0.01). There was statistically significant difference in AS score of the patients' family members with different age (F=4.390, P<0.05). There were significant differences in both IS and AS scores of the patients' family members of patients with different burn area (F=5.042, 3.131, P<0.05 or P<0.01). The AS score of the patients' family members with experience of accompanying in intensive care isolation unit was significantly lower than those without (t=-1.040, P<0.05). The SS score of the patients' family members with college education or above was significantly higher than those with high school (technical secondary school) or below (t=0.657, P<0.05). The IS score of the patients' family members with college education or above was significantly lower than those with high school (technical secondary school) or below (t=-1.438, P<0.05). The SS score of male family members of patients was significantly lower than those of female patients (t=4.149, P<0.05). Conclusions: The family members of burn patients in semi-closed ward have the most urgent need to ensure the patients receive the best treatment. Patients' age, total burn area, and their family members' gender, education level, experience of accompanying in intensive care isolation unit are the main factors affecting the psychological needs of family members of patients.

Electrocatalytic, Kinetic, and Mechanism Insights into the Oxygen-Reduction Catalyzed Based on the Biomass-Derived FeOx @N-Doped Porous Carbon Composites

A valid strategy for amplifying the oxygen reduction reaction (ORR) efficiency of non-noble electrocatalyst in both alkaline and acid electrolytes by decorated with a layer of biomass derivative nitrogen-doped carbon (NPC) is proposed. Herein, a top-down strategy for the generally fabricating NPC matrix decorated with trace of metal oxides nanoparticles (FeO_x NPs) by a dual-template assisted high-temperature pyrolysis process is reported. A high-activity FeO_x /FeNC (namely Hemin/NPC-900) ORR electrocatalyst is prepared via simply carbonizing the admixture of Mg₅ (OH)₂ (CO₃ )₄ and NaCl as dual-templates, melamine and acorn shells as nitrogen and carbon source, hemin as a natural iron and nitrogen source, respectively. Owing to its unique 3D porous construction, large BET areas (819.1 m² ∙g^-1 ), and evenly dispersed active sites (FeN_x , CN, and FeO parts), the optimized Hemin/NPC-900 catalyst displays comparable ORR catalytic activities, remarkable survivability to methanol, and preferable long-term stability in both alkali and acid electrolyte compared with benchmark Pt/C. More importantly, density function theory computations certify that the interaction between Fe₃ O₄ nanoparticles and arm-GN (graphitic N at armchair edge) active sites can effectually promote ORR electrocatalytic performance by a lower overpotential of 0.81 eV. Accordingly, the research provides some insight into design of low-cost non-precious metal ORR catalysts in theory and practice.

[Advance on the infectivity of SARS-CoV-2 infection at different stages]

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.

Cytotoxic Germacranolides from the Whole Plant of Carpesium minus

Eight new germacranolides, minusolides A-H (1-8), along with two known analogues, 9 and 10, were isolated from the whole plant of Carpesium minus. Their structures were elucidated by spectroscopic analysis. Compounds 1 and 2, and 6 and 9 are two pairs of rare epimers with opposite configurations at C-2 of the 2-methylbutyryloxy group. The absolute configurations were determined by X-ray diffraction studies. Compound 7 exhibited cytotoxic activities against MDA-MB-231, A549, and HCT-116 cells with IC₅₀ values of 6.1 ± 0.2, 8.4 ± 0.6, and 3.7 ± 0.6 μM, respectively. Compound 7 induced the apoptosis of HCT-116 cells via suppression of PARP and promoting cleavage of PARP.

[Effects on learning and memory and mitochondrial energy metabolism in hippocampus of mice by subacute exposure to n-hexane]

Objective: To study the effects on learning and memory, mitochondrial energy metabolism and ATPase activity of hippocampus in mice with subacute exposure to n-hexane. Methods: The SPF 40 Kunming mice were randomly divided into low, middle and high dose groups and control groups according to different dosages. Each group consisted of 10 mice. The mice were given n-hexane by gavage, the mice in the low, middle and high dose groups were given 0.2 ml/d of n-hexane at concentrations of 500, 1000 and 2000 mg/kg respectively, while the mice in the control group were given 0.2 ml/d of cooking oil once a day for 28 days. The y-type maze test, the activity of ATP Enzyme, mitochondrial respiratory chain enzyme complex Ⅰ-IV, the mrna of mitochondrial fusion gene (MFn1, Mfn2) and fission gene (FIs1) in brain tissues were performed. Results: Except for the wrong reaction times of low-dose exposure group in the first test, there existed significantly different in the first and second Y-maze tests in exposure groups and control group (P<0.05) ; in low, middle and high-dose group, the Na(+)-K(+)-ATPase activities were (8.27±2.65) , (5.38±1.55) , (3.55±1.69) μmol/gprot/h, and Ca(2+)-Mg(2+)-ATPase activities were (10.32±2.96) , (7.19±1.94) and (4.49±1.33) μmol/gprot/h, respectively. Compared with those in control group, the activities of Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase decreased significantly in middle-dose group and high-dose group (P<0.05) . Compared with those in control group, the activities of mitochondrial respiratory chain enzyme complex I-IV in each dose group were significantly decreased (P<0.05) . The expressions of Mfn1mRNA and Mfn2mRNA in each dose group was significantly lower than those in control group (P<0.05) . Conclusion: Subacute exposure to n-hexane can result in the decrease of activities of mitochondrial respiratory chain enzyme complex in hippocampus of mice, which may lead to the disorder of mitochondrial energy metabolism by the decrease of ATPase activity and the imbalance of mitochondrial fusion-division, which must be one of the mechanisms of impairment of learning and memory of mice induced by n-hexane.

[Long-term oncological outcomes of laparoscopic versus abdominal surgery in stage Ⅰa1 （LVSI+）-Ⅰb1 cervical cancer patients with different tumor size: a big database in China]

Objective: To compare the long-term oncological outcomes between laparoscopic and abdominal surgery in stage Ⅰa1 （lymph-vascular space invasion-positive, LVSI⁺）- Ⅰb1 cervical cancer patients with different tumor sizes. Methods: Based on the Big Database of Clinical Diagnosis and Treatment of Cervical Cancer in China (1538 project database), patients with stage Ⅰa1 （LVSI⁺）-Ⅰb1 cervical cancer who treated by laparoscopic or abdominal surgery were included. The 5-year overall survival (OS) and 5-year disease-free survival (DFS) between the two surgical approaches were compared under 1∶1 propensity score matching (PSM) in different tumor diameter stratification. Results: (1) A total of 4 891 patients with stage Ⅰa1 （LVSI⁺）-Ⅰb1 cervical cancer who underwent laparoscopy or laparotomy from January 1, 2009 to December 31, 2016 were included in the 1538 project database. Among them, 1 926 cases in the laparoscopic group and 2 965 cases in the abdominal group. There were no difference in 5-year OS and 5-year DFS between the two groups before matching. Cox multivariate analysis suggested that laparoscopic surgery was associated with lower 5-year DFS (HR=1.367, 95%CI: 1.105-1.690, P=0.004). After 1∶1 PSM matching, 1 864 patients were included in each group, and there was no difference in 5-year OS between the two groups （94.1% vs 95.4%, P=0.151）. While, the inferior 5-year DFS was observed in the laparoscopic group (89.0% vs 92.3%, P=0.004). And the laparoscopic surgery was associated with lower 5-year DFS (HR=1.420, 95%CI: 1.109-1.818, P=0.006). (2) In stratification analysis of different tumor sizes, and there were no difference in 5-year OS and 5-year DFS between the laparoscopic group and abdominal group in tumor size ≤1 cm, >1-2 cm and >2-3 cm stratification (all P>0.05). Cox multivariate analysis showed that laparoscopic surgery were not related to 5-year OS and 5-year DFS (P>0.05). In the stratification of tumor size >3-4 cm, there was no difference in 5-year OS between the two groups (P>0.05). The 5-year DFS in the laparoscopic group was worse than that in the abdominal group (75.7% vs 85.8%, P=0.025). Cox multivariate analysis suggested that laparoscopic surgery was associated with lower 5-year DFS (HR=1.705, 95%CI: 1.088-2.674, P=0.020). Conclusions: For patients with stage Ⅰa1 （LVSI⁺）-Ⅰb1 cervical cancer, laparoscopic surgery is associated with lower 5-year DFS, and the adverse effect of laparoscopic surgery on oncology prognosis is mainly reflected in patients with tumor size >3-4 cm. For patients with tumor sizes ≤1 cm, >1-2 cm and >2-3 cm, there are no difference in oncological prognosis between the two surgical approaches.

Citrus CitERF6 Contributes to Citric Acid Degradation via Upregulation of CitAclα1, Encoding ATP-Citrate Lyase Subunit α

Citric acid is the most abundant organic acid in citrus fruit, and the acetyl-CoA pathway potentially plays an important role in citric acid degradation, which occurs during fruit ripening. Analysis of transcripts during fruit development of key genes in the acetyl-CoA pathway and transient overexpression assay in citrus leaves indicated that CitAclα1 could be a potential target gene involved in citrate degradation. In order to understand more about CitAclα1, 23 transcription factors coexpressed with CitAclα1 in citrus fruit were identified by RNA-seq. Using dual-luciferase assays, CitERF6 was shown to trans-activate the promoter of CitAclα1 and electrophoretic mobility shift assays (EMSAs) showed that CitERF6 directly bound to a 5'-CAACA-3' motif in the CitAclα1 promoter. Furthermore, citric acid content was significantly reduced when CitERF6 was overexpressed in transgenic tobacco leaves. Taken together, these results indicate an important role for CitERF6 in transcriptional regulation of CitAclα1 and control of citrate degradation.

Long noncoding RNA SNHG8 promotes the proliferation of osteosarcoma cells by downregulating miR-542-3p

Small nucleolar RNA host genes (SNHGs) as a subset of long noncoding RNAs (lncRNAs) have critical roles in the pathogenesis of multiple malignancies, however, the role and molecular mechanisms of lncRNA SNHG8 in osteosarcoma (OS) remain unclear. In the present study, the correlation of SNHG8 or miR-542-3p with clinicopathological elements and prognosis in OS patents was estimated by TCGA cohort. Cell viability and invasion were assessed by MTT and Transwell assays. The interplay between SNHG8 and miR-542-3p was affirmed by a luciferase report assay. The effects of SNHG8 on miR-542-3p expression were examined in MG-63 and SW-1353 cells by qRT-PCR analysis. The results showed that incremental expression of SNHG8 or reduced expression of miR-542-3p was related to poor survival and tumor recurrence in OS patients. Overexpressing SNHG8 accelerated the growth and invasion of MG-63 cells, but silencing SNHG8 harbored an opposite effect in SW-1353 cells. Additionally, SNHG8 could negatively regulate miR-542-3p expression and bind with miR-542-3p, which attenuated SNHG8 induced cell proliferation. Taken together, these findings indicate that lncRNA SNHG8 promotes the proliferation of OS cells by downregulating miR-542-3p.

Effects of fine particulate PM2.5 on emphysema of mice via regulating FOXO3A/BIM axis

This study aims to investigate the role of PM_2.5 exposure in inducing apoptosis of alveolar epithelial cells and thereafter emphysema in mice, and the underlying mechanism. PM_2.5 exposure model in mice was constructed. Lung tissues were harvested from healthy mice and model mice for hematoxylin and eosin (H&E) staining. Protein levels of Forkhead box O3 (FOXO3A) and BIM in lung tissues were detected by Western blot. Subsequently, A549 cells were induced with increased doses of PM_2.5, followed by determination of relative levels of FOXO3A, BIM (Bcl-2 interacting mediator of cell death) and clv-caspase3. Apoptosis in PM_2.5-exposed A549 cells was assessed. Chromatin immunoprecipitation (ChIP) assay was conducted to uncover the interaction between FOXO3A and BIM. Finally, regulatory effects of FOXO3A/BIM on apoptosis of A549 cells were determined. PM_2.5 exposure resulted in expansion of alveolar spatial structure and decline of lung function, thus leading to emphysema in mice. Protein levels of FOXO3A and BIM were markedly upregulated in lungs of model mice. Relative levels of FOXO3A, BIM and clv-caspase3 were enhanced in PM_2.5 -exposed A549 cells, which were reversed by transfection of si-FOXO3A. ChIP assay confirmed that FOXO3A was able to regulate BIM transcription through binding its promoter regions. Importantly, regulatory effects of FOXO3A on apoptosis of PM_2.5 -exposed A549 cells were partially reversed by overexpression of BIM. PM_2.5 exposure leads to upregulation of FOXO3A, which triggers BIM transcription, thus inducing apoptosis of alveolar epithelial cells and emphysema in mice.

[The prevalence and relationship between laryngopharyngeal reflux disease, anxiety and depression in otolaryngology outpatients]

Objective: To obtain the prevalence laryngopharyngeal reflux disease (LPRD), anxiety and depression in otorhinolaryngology outpatients and to explore the role of mental and psychological factors (anxiety and depression) in their pathogenesis. Methods: A questionnaire survey of reflux symptom index(RSI) scale and hospital anxiety and depression (HAD) scale were used to report 1 111 cases of outpatients in Department of Otorhinolaryngology Head and Neck Surgery, Peking University People's Hospital, from July 2017 to June 2018 (486 males, 625 females, age of 18-96 years old, median age of 38[30,53] years old) and to obtain the prevalence of LPRD, anxiety and depression. RSI-positive patients were selected in the case group, and RSI-negative patients were selected in the control group. The differences in HAD scores between the two groups were compared, and the risk factors of laryngopharyngeal reflux were analyzed. Statistical analysis was performed using SPSS 20.0 software. Results: There were 151 cases in the case group and 960 cases in the control group. The prevalence of LPRD was 13.59% (151/1 111).There was no significant difference in the prevalence of LPRD between different genders (P>0.05). The prevalence rate was the highest in the 18-40 age group, and the difference in the prevalence of all age groups (18~ 40 years old; 41-65 years old; >65 years old) was statistically significant (P<0.05). The prevalence of LPRD among smokers and non-drinkers was higher than that of non-smokers and non-drinkers and the prevalence of the two groups was statistically significant (P<0.05). The most common symptoms of the RSI scale were pharyngeal foreign body sensation (92.72%,140/151), persistent clearing throat (88.74%,124/151), excessive sputum or nasal reflux (82.12%, 124/151). There were significant statistical differences between the two groups (P<0.05). Ninty-one patients with anxiety, the prevalence was 8.19%(91/1 111); 76 patients with depression, the prevalence was 6.84%(76/1 111).Among the LPRD patients, the hospital anxiety scale scored 29.14% (44/151), and the hospital depression scale scored 17.22% (26/151). The scores of anxiety symptoms and depressive symptoms in the LPRD group were higher than those in the non-LPRD group. The above scores were statistically significant (P<0.05). Logistic regression analysis showed that smoking, anxiety and symptoms of gastroesophageal reflux disease were independent risk factors for laryngopharyngeal reflux. Conclusions: The prevalences of LPRD, anxiety and depression in the otorhinolaryngology clinic are 13.59%, 8.19% and 6.84%, respectively. Among patients with laryngopharyngeal reflux, the prevalence of anxiety is 29.14%, and the prevalence of depression is 17.22%. Age, smoking, drinking, alcohol consumption, education level, course of disease, symptoms of gastroesophageal reflux disease, pharyngeal foreign body sensation, etc. are related to LPRD. Mental factors (anxiety and depression) may play a role in LPRD. Smoking, anxiety symptoms and symptoms of gastroesophageal reflux disease are closely related to the incidence of LPRD.

Taxodisones A and B: bioactive C30-terpenes with new skeletons from Taxodium distichum and their biosynthetic origin

Herein, taxodisones A and B were isolated from the seeds of T. distichum, and the structures, configurations, bioactivities and origin of these compounds were determined.

A unique polymersome covered by loop-cluster polyamine corona

The comb with teeth of amphiphilic block copolymer possessing hydrophilic polyethyleneimine (inside) and hydrophobic poly(2-phenyl-2-oxazoline) (outside) self-assembled into extremely stable loop-cluster covered polymersome with very thin vesicular wall (ca. 3 nm).

Patulignans A–C, three structurally unique lignans from the leaves of Melicope patulinervia

(±)-Patulignans A–C (1–3), α-glucosidase inhibitors bearing unprecedented lignan skeletons with twelve carbons at side chains were isolated from the leaves of Melicope patulinervia.

[Preliminary application of transjugular intrahepatic portosystemic shunt in individualized treatment of patients with cirrhotic portal hypertension complicated with refractory ascites and variceal hemorrhage]

Objective: To investigate the feasibility, efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) in the individualized treatment of patients with refractory ascites and variceal hemorrhage caused by portal hypertension. Methods: Prospective study of clinical data of 47 patients with portal hypertension and refractory ascites and variceal bleeding admitted to the Affiliated Hospital of Xuzhou Medical University from August 2017 to December 2018, 26 males and 21 females, aged 23-75 (52±14) years old. The Viabahn stent was used to control the diameter of the shunt and the preoperative interval of PPG after individualized TIPS was determined according to the preoperative liver function Child-Pugh classification. The PPG of the Child A and B patients was <10 mm Hg (1 mmHg=0.133 kPa), Child-Pugh C grade patients with postoperative PPG interval values of 12 to 15 mmHg. The success rate, hemostasis rate, ascites remission rate, and complication rate were recorded. Results: Forty-seven patients were with a success rate of 100%, and there was no surgically related fatal complications. The portal pressure gradients of patients with Child-Pugh A, B and Child-Pugh C were reduced from preoperative (22.5±5.4), (24.4±2.6) mm Hg to postoperative (8.8±2.5), (13.2±1.1) mm Hg (all P<0.05). All the patients were followed up for 6 to 24 months, with a median follow-up of 13 months. The success rate of hemostasis in patients with upper gastrointestinal bleeding was 93.5% (29/31), the remission rate of patients with refractory ascites was 14/16, the postoperative rebleeding rate was 6.5% (2/31), the incidence of hepatic encephalopathy was 8.5% (4/47), and the shunt disorder was 2.1% (1/47). Conclusion: The use of Viabahn stent for individualized TIPS in the treatment of portal hypertension with refractory ascites and variceal hemorrhage is feasible, and the clinical efficacy is affirmative, which can reduce the incidence of postoperative hepatic encephalopathy and shunt dysfunction.

[Establishment and research of a New Zealand rabbit model of laryngopharyngeal reflux]

Objective: To establish a New Zealand rabbit animal model of laryngopharyngeal reflux disease (LPRD) using esophageal balloon together with metal internal stent dilation and to investigate the changes of mucosa. Methods: 20 New Zealand rabbits were randomly divided into experimental group and control group, with 10 in each group. Balloon dilatation and metal internal stent dilation were carried out in experimental group to reproduce the animal model of LPRD.The middle of balloon was placed at the lower esophageal sphincter (LES) while the stent was placed at the upper esophageal sphincter (UES). The guide wire was placed in the control group, but the balloon was not expanded and the stent was not placed. The general condition, pH value of hypopharynx, laryngeal histopathology and changes of pepsin content of New Zealand rabbits were observed regularly. The difference between experimental group and control group was compared. Results: The 24-hour Dx-pH monitoring results showed that the number of reflux episodes(20.0[9.5, 35.0], 13.0[6.5, 22.0]), and the percent time below pH 5.5 (1.36%[0.60%, 4.57%], 1.36%[0.43%, 2.77%]) in the experimental group at the 2nd and 4th week were significantly different from those in the control group (0[0,3.0], 1.0[0.5, 3.8]; 0[0, 0.01%], 0[0, 0], respectively, all P<0.01), suggesting that the experimental group New Zealand rabbits developed LPRD. Compared with the control group under microscope, lymphocytes infiltration and submucosal gland hyperplasia increased in the mucosa of the throat of the experimental group. The results of pepsin immunohistochemical staining between the two groups were statistically significant (P=0.014). Conclusion: The use of balloon dilatation of the LES combined with metal stent dilatation of the UES can successfully establish a laryngopharyngeal reflux model, and lesions in the throat tissue can be observed.

[Trend in proportion and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer]

Objective: To analyze the 13 years trend in proportion, risks factors and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer by using multi-center data of cervical cancer in China. Methods: The clinicopathological data of 46 313 patients with cervical cancer treated from 37 hospitals in China were obtained from January 2004 to December 2016. Using clinical and pathologic data, each patient's stage was reclassified by the 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. A total of 19 041 patients were selected according to the following criteria: FIGO stage Ⅰa2 to Ⅱa2, underwent type B or C radical hysterectomy and pelvic lymphadenectomy. All the patients were divided into two groups: the study group of 1 888 patients aged 35 years or younger and the control group of 17 153 patients aged over 35 years. The 13 years trend in proportion of young women with stage Ⅰa2 to Ⅱa2 cervical cancer, risks factors and clinicopathological characteristics of two groups were retrospectively analyzed. Results: (1) The total number of hospitalized patients with stage Ⅰa2 to Ⅱa2 cervical cancer increased annually. However, a downward trend of patients aged 35 years or younger was observed (P<0.01) . The constituent ratio of patients aged 35 years or younger was significantly greater during 2004-2010 than that during 2011-2016 [12.6% (820/6 484) and 8.5% (1 068/12 557) , respectively; χ(2)=82.101, P<0.01]. (2) Compared with patients aged over 35 years, patients aged 35 years or younger had an earlier age at menarche, a later age at marriage, lesser gravida and parity (all P<0.01). The positive rate of high-risk HPV infection was not statistically different between two groups (all P>0.05). (3) The proportions of stage Ⅰ, exophytic type and non-squamous histological type in patients aged 35 years or younger were clearly higher than those in patients aged over 35 years (83.4% vs 68.5%, P<0.01; 63.2% vs 56.2%, P<0.01; 13.9% vs 12.0%, P<0.05, respectively). Whereas the poor differentiation ratios of the two groups had no statistical significance (P>0.05). (4) As for the postoperative pathological risk factors, the rate of surgical margin involvement in patients aged 35 years or younger was lower than that aged over 35 years (1.1% vs 1.8%, P<0.05), and the rate of depth of stromal invasion >1/2 in patients aged 35 years or younger was lower than that in patients aged over 35 years (40.1% vs 50.9%, P<0.01). In addition, there were no significant difference in parametrial margin involvement, tumor size and lymph vascular space invasion between two groups (all P>0.05). Conclusions: The trend in proportion among hospitalized patients for stage Ⅰa2 to Ⅱa2 cervical cancer in young women is decreasing yearly. Compared with cervical cancer in middle-aged and elderly women, cervical cancer in young women have an earlier age at menarche, a higher proportion of stage Ⅰ patients and non-squamous histological type. In terms of the postoperative pathological risk factors, the rate of surgical margin involvement and depth of stromal invasion >1/2 in young women with cervical cancer are lower than in middle-aged and elderly women.

Taicrypnacids A and B, a Pair of C37 Heterodimeric Diterpenoid Stereoisomers from Taiwania cryptomerioides

Two uncommon C₃₇ heterodimeric diterpenoids, taicrypnacids A (1) and B (2), and a known labdane-type diterpenoid (3) were isolated from the leaves of Taiwania cryptomerioides. Several techniques, such as comprehensive spectroscopic analysis, chemical conversion, X-ray crystallography, and ECD data, were employed to define the structures. The two new compounds displayed cytotoxicity against human breast cancer (MCF-7), osteosarcoma (U-2 OS), and human colon carcinoma (HCT-116) cell lines, while the methyl ester 1a showed no activity. Compound 1 induced Ca²⁺-ROS pathway-mediated endoplasmic reticulum stress, and excessive stress led to cell death by activating apoptosis and autophagy.

[The role of PDK1 in the transition of endothelial to hematopoietic cells]

目的

研究磷酸肌醇依赖性激酶1（PDK1）在内皮细胞向造血细胞转化阶段对造血干细胞（HSC）发生的影响。

方法

应用Vec-Cre在内皮细胞中特异性敲除PDK1基因，取对照组PDK1^fl/fl、PDK1^fl/+小鼠及敲除组Vec-Cre；PDK1^fl/fl小鼠胚胎的主动脉-性腺-中肾区（AGM区）细胞进行集落形成实验，检测PDK1基因对造血祖细胞功能的影响；取对照组和敲除组AGM区细胞行移植实验，检测PDK1对HSC功能的影响；取对照组和敲除组AGM区细胞，通过流式细胞术检测PDK1对能够向造血转化的CD31⁺c-Kit^high细胞群比例、细胞周期及细胞凋亡的影响；分选对照组和敲除组AGM区CD31⁺c-Kit^high细胞群，通过Real-time PCR检测PDK1对内皮向造血转换相关的转录因子（RUNX1、P2-RUNX1、GATA2）的影响。

结果

PDK1敲除后，造血祖细胞形成的克隆形态变小，数目减少[敲除组CFU-GM为（24±5）个/ee，对照组为（62±1）个/ee，P=0.001]；破坏了造血干细胞重建造血及多向分化的能力（敲除组移植5只，0只重建，对照组移植7只，5只重建，P=0.001）；AGM区CD31⁺c-Kit^high比例降低[敲除组CD31⁺c-Kit^high比例为（0.145±0.017）%，对照组比例为（0.385±0.04）%，P=0.001]；并且AGM区由内皮细胞向造血细胞转换的关键转录因子表达下降，但对CD31⁺c-Kit^high细胞的增殖和凋亡无明显影响。

结论

在内皮细胞中特异敲除PDK1基因，导致具有向造血转化的内皮细胞群比例降低，影响了HSC的发生，破坏了HSC重建造血的能力。