Prognostic Roles of N6-Methyladenosine METTL3 in Different Cancers: A System Review and Meta-Analysis

BACKGROUND

Recent studies have shown that methyltransferase-like 3, a catalytic enzyme that is predominant in the N6-methyladenosine methyltransferase system, is abnormally expressed in various types of carcinoma and is correlated with poorer prognosis. However, the clinical functions of methyltransferase-like 3 in the prognosis of tumors are not fully understood.

METHODS

We identified studies by searching PubMed, Web of Science, and MedRvix for literature (up to June 30, 2020), and collected a total of 9 studies with 1257 patients for this meta-analysis. The cancer types included gastric cancer, breast cancer, non-small cell lung cancer, bladder cancer, colorectal cancer and ovarian. We further used The Cancer Genome Atlas dataset to validate the results.

RESULTS

High methyltransferase-like 3 expression clearly predicted a worse outcome (high vs. low methyltransferase-like 3 expression group; hazard ratio = 2.09, 95% confidence interval 1.53-2.89, P = 0.0001). Moreover, methyltransferase-like 3 expression was associated with differentiation (moderate + poor vs. well, pooled odds ratio = 1.76, 95% confidence interval 1.32-2.35, P = 0.0001), and gender (male vs. female, pooled odds ratio = 0.73, 95% confidence interval 0.55-0.97, P = 0.029).

CONCLUSION

Our results suggest that methyltransferase-like 3 upregulation is significantly associated with poor prognosis and could potentially function as a tumor biomarker in cancer prognosis.

Sirtuin 3 protects against anesthesia/surgery-induced cognitive decline in aged mice by suppressing hippocampal neuroinflammation

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a very common complication that might increase the morbidity and mortality of elderly patients after surgery. However, the mechanism of POCD remains largely unknown. The NAD-dependent deacetylase protein Sirtuin 3 (SIRT3) is located in the mitochondria and regulates mitochondrial function. SIRT3 is the only sirtuin that specifically plays a role in extending lifespan in humans and is associated with neurodegenerative diseases. Therefore, the aim of this study was to evaluate the effect of SIRT3 on anesthesia/surgery-induced cognitive impairment in aged mice.

METHODS

SIRT3 expression levels were decreased after surgery. For the interventional study, an adeno-associated virus (AAV)-SIRT3 vector or an empty vector was microinjected into hippocampal CA1 region before anesthesia/surgery. Western blotting, immunofluorescence staining, and enzyme-linked immune-sorbent assay (ELISA) were used to measure the oxidative stress response and downstream microglial activation and proinflammatory cytokines, and Golgi staining and long-term potentiation (LTP) recording were applied to evaluate synaptic plasticity.

RESULTS

Overexpression of SIRT3 in the CA1 region attenuated anesthesia/surgery-induced learning and memory dysfunction as well as synaptic plasticity dysfunction and the oxidative stress response (superoxide dismutase [SOD] and malondialdehyde [MDA]) in aged mice with POCD. In addition, microglia activation (ionized calcium binding adapter molecule 1 [Iba1]) and neuroinflammatory cytokine levels (tumor necrosis factor-alpha [TNF-α], interleukin [IL]-1β and IL-6) were regulated after anesthesia/surgery in a SIRT3-dependent manner.

CONCLUSION

The results of the current study demonstrate that SIRT3 has a critical effect in the mechanism of POCD in aged mice by suppressing hippocampal neuroinflammation and reveal that SIRT3 may be a promising therapeutic and diagnostic target for POCD.

Repeated exposure to propofol in the neonatal period impairs hippocampal synaptic plasticity and the recognition function of rats in adulthood

Anesthesia of neonates with propofol induces persistent behavioral abnormalities in adulthood. Although propofol-triggered apoptosis of neurons in the developing brain may contribute to the development of cognitive deficits, the mechanism of neurotoxicity induced by neonatal exposure to propofol remains unclear. In this study, the effects of neonatal propofol anesthesia on synaptic plasticity and neurocognitive function were investigated. Postnatal day 7 (PND-7) Sprague-Dawley rats were intraperitoneally injected with fat emulsion or 20, 40 or 60 mg/kg propofol for three consecutive days. The expression of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB) and postsynaptic density protein 95 (PSD-95) in the rat hippocampus at PND-10 and PND-12 was measured by Western blotting. The number of dendritic branches, total dendritic length and dendritic spine density were observed by Golgi-Cox staining 24 h and 72 h after the last propofol administration. Long-term potentiation (LTP) was measured electrophysiologically in hippocampus of PND-60 rats to evaluate the synaptic function. The learning and memory abilities of rats were evaluated by Morris water maze (MWM) experiments, Novel object recognition test (NORT) and Object location test (OLT) at PND-60. Our results showed that neonatal exposure to propofol significantly inhibited the expression of BDNF, TrkB and PSD-95 in the rat hippocampus. The number of dendritic branches, total dendritic length and dendritic spine density of neurons in the rat hippocampus were markedly reduced after neonatal propofol anesthesia. LTP was significantly diminished in hippocampus of PND-60 rats after repeated exposure to propofol in the neonatal period. Morris water maze experiments showed that repeated neonatal exposure to propofol significantly prolonged the escape latency and decreased the time spent in the target quadrant and the number of platform crossings. NORT and OLT showed that repeated neonatal exposure to propofol markedly reduced the Investigation Time for novel object or location. All of the results above indicate that repeated exposure to propofol in the neonatal period can impair hippocampal synaptic plasticity and the recognition function of rats in adulthood.

[Prevalence of CYP2C19 gene mutations in patients with coronary heart disease and its biological activation effect in clopidogrel antiplatelet response]

Objective: The purpose of this study was to investigate the effects of CYP2C19 gene mutations on clopidogrel antiplatelet activity in the patients with coronary heart disease treated by percutaneous coronary intervention. Methods: Patients with coronary heart disease, who hospitalized in the Second Affiliated Hospital of Nanchang University from March 2011 to June 2019, and healthy individuals with matching genetic background, gender, and age as controls were included in this study. Basic clinical data were analyzed and blood samples of all research subjects were obtained for extraction of DNA, and Sanger first-generation sequencing method was used to detect CYP2C19 gene mutation from full exon and exon and intron junction. CYP2C19 gene variations in patients with coronary heart disease were compared with the 1000 Genomes Browse database and the sequencing results of healthy controls to determine whether the gene variation was a genetic mutation or a genetic polymorphism. After that, PolyPhen-2 prediction software was used to analyze the harmfulness of gene mutations to predict the effect of mutations on protein function. The same dose of CYP2C19 wild-type plasmid and the CYP2C19 gene mutant plasmids were transfected into human normal liver cells HL-7702. After transfection of 24 h, the expression of CYP2C19 protease in each group was detected. The liver S9 protein was incubated with clopidogrel, acted on platelets to detect the platelet aggregation rate and the activity of human vasodilator-activated phosphoprotein (VASP). Results: A total of 1 493 patients with coronary heart disease (59.36%) were enrolled, the average age was (64.5±10.4) years old, of which 1 129 were male (75.62%). Meanwhile, 1 022 healthy physical examination volunteers (40.64%) were enrolled, and the average age was (64.1±11.0) years old, of which 778 were male (76.13%). A total of 5 gene mutations of CYP2C19 gene were identified in 12 patients (0.80%), namely, 4 known mutations T130K (1 case), M136K (6 cases), N277K (3 cases), V472I (1 case) and one new mutation G27V (1 case), no corresponding gene mutation was found in healthy controls. It was found that T130K and M136K were probably damaging, G27V was possibly damaging, and N277K and V472I were benign mutations. In vitro, we demonstrated that the platelet aggregation rate of the M136K gene mutation group was 24.83% lower than that of the wild type (59.58% vs. 34.75%; P<0.05), and the phosphorylated VASP level was 23.0% higher than that of the wild type (1.0 vs. 1.23; P<0.05). However, the platelet aggregation rate and phosphorylated VASP level were similar between of G27V, T130K, N277K, V472I gene mutation groups and wild type group (P>0.05). Conclusions: In this study, 5 gene mutations are defined in patients with coronary heart disease, namely G27V, T130K, M136K, N277K, V472I. In vitro functional studies show that CYP2C19 gene mutation M136K, as a gain-of-function gene mutation, can enhance the activation of CYP2C19 enzyme on clopidogrel, thereby inhibiting the platelet aggregation rate.

[Analysis of online education for public health and preventive medicine]

Since the outbreak of the Coronavirus Disease 2019 (COVID-19), universities have carried out online education for public health and preventive medicine courses under the policy of "Suspending Classes Without Stopping Learning" launched by the Chinese government. The Public Health and Preventive Medicine Committee of the Ministry of Education Steering Committee for Medical Education investigated the online teaching activities in the member universities. This study presents the survey results, discusses the existing problems, and proposes suggestions for further reforms on mixed teaching activities.

[Accuracy and clinical outcome of a real-time surgical navigation system for the placement of quad zygomatic implants]

Objective: To evalute the accuracy and clinical outcome of a real-time navigation system for the placement of quad zygomatic implants. Methods: Twenty-four patients [9 males and 15 females, mean age was (50.8±14.7) years old], from January 2015 to December 2019, with 96 zygomatic implants placed under a real-time navigation system in Department of Second Dental Center and Department of Oral Implantology of Ninth People's Hospital, Shanghai Jiaotong University School of Medicine were included in the study. The preoperative and the postoperative multislice CT or cone-beam CT were fused to measure and record the entry, exit and angle deviation between the planned and placed implants. The implants were divided into groups according to implant insertion approach (real-time navigation and free-hand), implant length (<47.5 mm and ≥47.5 mm) and implant position (proximal and distal implant). And the differences of implant accuracy were analyzed. The intraoperative and postoperative complications were also recorded. The implant survival rate was evaluated after 6 months follow-up. A P value<0.05 indicates statistical significance. Results: The mean entry, exit and angle deviation of zygomatic implants were (1.49±0.64) mm, [2.03(1.58, 2.40)] mm and (2.49°±1.12°), respectively. The average entry, exit and angle deviation of the navigation guided implant insertion group were (1.45±0.60) mm, (1.96±0.44) mm and (2.66±1.13°) respectively, while those of the free-hand group were (1.50±0.64) mm, (2.04±0.79) mm and (2.50°±1.13°) respectively. There was no significant difference between the two groups (P>0.05). The average entry, exit and angle deviation of the group with length<47.5 mm were (1.42±0.60) mm, (2.13±0.60) mm and (2.61°±1.08°) respectively and those of the group with length ≥ 47.5 mm were (1.52±0.65) mm, (1.98±0.82) mm and (2.43°±1.14°) respectively. No significant difference was found between the two groups (P>0.05). In proximal implant group, the average entry, exit and angle deviation were (1.55±0.69) mm, (2.05±0.92) mm and (2.48°±1.16 °) respectively while those of distal implant group were (1.43±0.57) mm, (2.01±0.57) mm and (2.49°±1.10°), respectively. No significant difference was detected between the two groups (P>0.05). All zygomatic implants were placed uneventfully. There were no intra-operative complications, and post-operative reversible complications developed in 3 patients. Two zygomatic implants were lost and the overall zygomatic implant survival rate was 97.9% (94/96) within a follow-up of 6 months. Conclusions: Quad zygomatic implant placement can be achieved with high accuracy and predictable clinical outcome under guidance of a real-time navigation system.

[Association of plasma roundabout 4 concentration with pulmonary ventilation function decline in COPD patients]

Objective: To investigate the association of plasma roundabout 4 concentration with pulmonary ventilation function decline in chronic obstructive pulmonary disease (COPD) patients. Methods: To get the effective data, the study was conducted in the outpatient department of West China Hospital from September 2017 to September 2018. The subjects meeting the inclusion and exclusion criteria were continuously included. Among them, the COPD group (75 cases) was from the respiratory outpatient department, and the healthy control group (57 cases) was from the health examination center at the same time. Data of basic demographic characteristics, clinical characteristics, pulmonary ventilation function parameters and blood samples were collected. The concentrations of roundabout 4, C reactive protein (CRP), interleukin (IL)-6, IL-8, IL-1b and tumor necrosis factor (TNF)-α in plasma were detected, and the differences among groups were compared, the correlation between plasma roundabout 4 and pulmonary ventilation function parameters and inflammatory factors was analyzed. The diagnostic efficiency of roundabout 4 to COPD was analyzed according to receiver operating characteristic (ROC) curve. Results: The plasma concentration of roundabout 4 in COPD group was significantly higher than that in healthy control group [(41.3±14.2) vs (27.7±13.3) ng/L; P<0.001], the sensitivity and specificity of roundabout 4 in the diagnosis of COPD were 0.827 and 0.702 respectively. Correlation analysis showed that the plasma concentration of roundabout 4 was negatively correlated with lung function parameters forced expiratory volume in one second/forced vital capacity (FEV(1)/FVC), the first second forced expiratory volume as a percentage of the estimated value (FEV(1)%pred), forced exhalation of 50% and 25% lung capacity (MEF50, MEF25) and maximal mid-expiratory flow (MMEF) (r=-0.399, -0.321, -0.439, -0.363, -0.458; all P<0.001), positively correlated with CRP (adjusted r=0.311, P<0.001). Conclusion: The increased concentration of roundabout 4 in plasma leads to the decline of pulmonary ventilation function in COPD patients.

Distinct effects of antihypertensives on depression in the real-world setting: A retrospective cohort study

BACKGROUND

Evidence is increasing that pathways of antihypertensives may have a role in the pathogenesis of depression. However, how the class of antihypertensives affects depression risk remains unclear.

METHODS

The effects of different classes of antihypertensives on depression were explored using an insurance database in Beijing, China. Antihypertensives in our study included calcium channel blockers (CCBs), angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), beta-blockers (BBs), and diuretics (DIUs). Those initially treated with only one class of antihypertensives were included. Stratified analysis was conducted for demographic characteristics, comorbidities, and statin prescriptions.

RESULTS

In total, 181,709 newly detected hypertension patients were included. The median follow-up period was 4.33 years and 19,030 participants were with depression by the end. After adjusting for covariates, the incidence density (95% confidence interval, CI) of depression in the BB, ACEI, DIU, CCB, and ARB groups was 3.16 (2.98-3.33), 3.10 (2.91-3.29), 2.70 (2.45-2.94), 2.67 (2.53-2.81), and 2.30 (2.16-2.43) per 100 person-years, respectively. Compared with ARB group, the hazard ratio (95% CI) of depression for BB, ACEI, DIU, and CCB group was 1.37 (1.32-1.43), 1.35 (1.28-1.42), 1.17 (1.08-1.27), and 1.16 (1.12-1.21), respectively. Stratified analysis suggested the highest depression ID remained within the BB or ACEI group.

LIMITATIONS

Detailed clinical information was unavailable, which may introduce bias. Patients on monotherapy as initial treatment were included and caution is needed for extrapolation.

CONCLUSIONS

Compared with ARBs, there may be a class effect of other antihypertensives on the risk of depression.

[Clinical characteristics of 57 patients with polyarteritis nodosa and renal involvement]

Objective: To investigate the clinical characteristics of polyarteritis nodosa (PAN) patients with renal involvement. Methods: PAN patients admitted to the department of rheumatology, department of pediatrics, department of nephrology, general internal medicine department and department of vascular surgery at Peking Union Medical College Hospital from June 2012 to August 2018 were enrolled in this study and were divided into two groups according to renal involvement or not. The clinical characteristics were analyzed. Results: A total of 94 PAN patients were finally enrolled and 57 (60.64%) presented kidney manifestation. The mean age of onset was (37.76±17.40) years old and the interval from onset to diagnosis was 10 (0 to 240) months. Forty patients were misdiagnosed once or more times. In patients with renal involvement, 9 cases suffered from renal ischemia or infarction, 31 with microscopic haematuria, 26 with proteinuria, renal artery or its branch involved in 17 cases, renal vein thrombosis in 1 case, 4 cases with pyeloureterectasis, one case with renal fascia thickening, 33 cases with impaired renal function (serum creatinine>84 μmol/L) including creatinine>140 μmol/L in 10 patients. Renal artery branch stenosis was the most common presentation [9 cases (52.94%)] of renal vascular involvement, other abnormalities including nodular dilatation [4 cases (23.53%)], occlusion [3 cases (17.65%)]. There were significant differences (P<0.05) in the PAN patients with and without renal involvement in the following: age of onset [(33.72±16.13) years vs. (43.97±17.66) years, t(2)=2.901, P=0.005], weight loss(≥4kg since PAN onset) [25(43.86%) vs. 7(18.92%), χ(2)=6.216, P=0.013], elevation of diastolic blood pressure [22(38.60%) vs. 7(18.92%), χ(2)=4.072, P=0.044], acromegaly gangrene [18(31.58%) vs. 21(56.76%), χ(2)=5.859, P=0.015], and gastrointestinal artery involvement [20(35.09%) vs. 6(1.22%), χ(2)=3.993, P=0.046]. Laboratory parameters and the application of glucocorticoid and cyclophosphamide therapies were similar in two groups (all P>0.05). Conclusion: Young PAN patients are more likely to be associated with renal involvement, especially gastrointestinal arteries.

[Feasibility and safety of new "blind" axillary vein puncture technique in pacemaker implantation]

Objective: To explore the feasibility and safety of a newly developed simple and rapid axillary vein puncture technique based on the surface landmarks for pacemaker implantation. Methods: From January to November 2018, we enrolled 110 patients who underwent pacemaker implantation in Beijing Anzhen Hospital. Basic clinical characteristics, such as gender, age, major diagnosis, type of pacemaker, and His-purkinje system pacing, were collected. The success rate of this axillary vein puncture technique, complications, and technical parameters of present puncture method were analyzed. Results: There were 58 (52.7%) male patients in this cohort and the average aged was (70.26±10.45) years old. This "blind" axillary vein puncture method was successful in 105 out of 110 patients (95.5%). The relevant puncture-related parameters included: the distance between points "a and b" was (3.89±0.40) cm, the first angle α was (25.84±5.54)° and the second angle β was (66.18±10.26)°. There were no puncture-related complications, such as hematoma, pneumothorax and hemothorax. Conclusion: The new "blind" axillary vein puncture approach is a simple, effective and safe technique for pacemaker implantation, which is easy to learn and practice and suitable for promotion.

Transient Receptor Potential V Channels Are Essential for Glucose Sensing by Aldolase and AMPK

Fructose-1,6-bisphosphate (FBP) aldolase links sensing of declining glucose availability to AMPK activation via the lysosomal pathway. However, how aldolase transmits lack of occupancy by FBP to AMPK activation remains unclear. Here, we show that FBP-unoccupied aldolase interacts with and inhibits endoplasmic reticulum (ER)-localized transient receptor potential channel subfamily V, inhibiting calcium release in low glucose. The decrease of calcium at contact sites between ER and lysosome renders the inhibited TRPV accessible to bind the lysosomal v-ATPase that then recruits AXIN:LKB1 to activate AMPK independently of AMP. Genetic depletion of TRPVs blocks glucose starvation-induced AMPK activation in cells and liver of mice, and in nematodes, indicative of physical requirement of TRPVs. Pharmacological inhibition of TRPVs activates AMPK and elevates NAD+ levels in aged muscles, rejuvenating the animals' running capacity. Our study elucidates that TRPVs relay the FBP-free status of aldolase to the reconfiguration of v-ATPase, leading to AMPK activation in low glucose.

[Study on the current status of postgraduates training in public health and preventive medicine in China in 2016]

To investigate the current status of postgraduates training in public health and preventive medicine in China. In this study, a questionnaire survey was conducted among directors of enrollment and teaching in 22 universities with postgraduate admission qualifications in corresponding disciplines nationwide. In 2016, full-time postgraduates were mainly academic masters. In addition to the graduate entrance examination, the common enrollment mode in colleges was to enroll a high qualified student with recommendations from relevant experts or institutions and an exemption from entrance examination (20/22). The emphasis on training contents between academic and public health master was different. Currently, the scale of public health postgraduate enrollment in public health and preventive medicine in China is stable, and the training program is reasonable, but there is an issue of monotonous model and uneven distribution of enrollment.

[Investigation on the current status of the cultivation of the master of public health (MPH) in colleges in China]

In order to understand the status of the cultivation of the masters of public health (MPH) in colleges in China and improve the cultivation model, an electronic questionnaire survey were conducted among 22 schools of public health in colleges. The result showed that the size and the enrolment scale of Chinese MPH students were relatively small, and the training objectives were still unclear. There was no obvious difference between the curriculum setting for MPH and academic master degree. The practical skill-oriented courses and emergency response ability of public health practice were insufficient. The cultivation model of MPH should be improved in future.

[Analysis of the contradiction between the supply and demand of Chinese graduate students' emergency professional ability in public health and preventive medicine in China]

In order to underst and the status of health emergency personnel training development and raising coping measures, electronic questionnaire surveys were conducted among 22 colleges and universities in different region of China. The result showed that colleges universities in China invested less in the training of emergency personnel. It is different and emphasized particularly for the cultivation of emergency professional ability among different types of public health students. Universities and employer hold relative evaluation of students' emergency professional ability with distinct regional differences.

MiR-21-5p enhances the progression and paclitaxel resistance in drug-resistant breast cancer cell lines by targeting PDCD4

MiR-21-5p has been identified as an oncogene to enhance human tumor progression. Here, we explored the mechanism by which miR-21-5p regulated the progression and paclitaxel (PTX) resistance in drug-resistant breast cancer (BC) cell lines. qRT-PCR assays were used to assess the expression levels of miR-21-5p and PDCD4 mRNA, and western blotting was used to detect PDCD4 protein level in PTX-resistant BC cell lines. Dual-luciferase reporter assay was used to observe the interaction between miR-21-5p and PDCD4 in PTX-resistant BC cell lines. Cell proliferation ability and IC50 values of PTX were measured by CCK-8 assay, cell cycle progression and apoptosis were determined with flow cytometry analysis, and cell migration and invasion capacities were analyzed using Transwell assay. Xenograft mice assay was used to validate the important role of miR-21-5p as a regulator on PTX-resistance BC cells growth in vivo. Then, we found that miR-21-5p was upregulated and PDCD4 was downregulated in BC tissues and PTX-resistant BC cell lines. MiR-21-5p silencing or PDCD4 overexpression ameliorated PTX resistance and inhibited the progression in PTX-resistant BC cell lines. Moreover, PDCD4 was demonstrated to be a direct target of miR-21-5p. MiR-21-5p exerted its regulatory effect by PDCD4 in PTX-resistant BC cell lines. Additionally, miR-21-5p silencing inhibited tumor growth in vivo. Therefore, our study demonstrated that miR-21-5p silencing ameliorated PTX resistance and inhibited the progression in PTX-resistant BC cell lines at least partly by targeting PDCD4, providing miR-21-5p as an effective therapeutic target for PTX-resistant BC treatment.

Ca2+-PKCα-ERK1/2 signaling pathway is involved in the suppressive effect of propofol on proliferation of neural stem cells from the neonatal rat hippocampus

Neonatal exposure to propofol induces persistent behavioral abnormalities in adulthood. In addition to triggering the apoptosis of neurons in the developing brain, anesthetics may contribute to the development of cognitive deficits by interfering neurogenesis. Given the importance of neural stem cell (NSC) proliferation in neurogenesis, the effect of propofol on NSC proliferation and the mechanisms underlying this effect were investigated. Hippocampal NSC proliferation from neonatal rats was examined using 5-bromo-2'-deoxyuridine incorporation assays in vitro. The [Ca²⁺]i was analyzed using flow cytometry. The activations of protein kinase C (PKC)-α and extracellular signal-regulated kinases 1/2 (ERK1/2) were measured by western blot. Our results showed that propofol significantly inhibited NSC proliferation in vitro. [Ca²⁺]i and activations of PKCα and ERK1/2 in NSCs were markedly suppressed by propofol (5, 10, 20, 40 and 80 μM). Ca²⁺ channel blocker verapamil, PKCα inhibitor chelerythrine and ERK1/2 kinase inhibitor PD98059 exerted their maximal effects on NSC function at concentrations of 20, 10 and 20 μM, respectively. Propofol (20 μM) could not produce further additional suppression effects when used in combination with verapamil (20 μM), chelerythrine (10 μM) or PD98059 (20 μM). In addition, phorbol-12-myristate-13-acetate (PMA, a activator of PKC) markedly attenuated the suppressive effects of propofol on ERK1/2 phosphorylation and NSC proliferation. The inhibition effects on PKCα activation, ERK1/2 phosphorylation and NSC proliferation induced by propofol were significantly improved by BayK8644 (a calcium channel agonist). These results indicate that propofol can inhibits hippocampal NSC proliferation by suppressing the Ca²⁺-PKCα-ERK1/2 signaling pathway.

Hierarchical activation of compartmentalized pools of AMPK depends on severity of nutrient or energy stress

AMPK, a master regulator of metabolic homeostasis, is activated by both AMP-dependent and AMP-independent mechanisms. The conditions under which these different mechanisms operate, and their biological implications are unclear. Here, we show that, depending on the degree of elevation of cellular AMP, distinct compartmentalized pools of AMPK are activated, phosphorylating different sets of targets. Low glucose activates AMPK exclusively through the AMP-independent, AXIN-based pathway in lysosomes to phosphorylate targets such as ACC1 and SREBP1c, exerting early anti-anabolic and pro-catabolic roles. Moderate increases in AMP expand this to activate cytosolic AMPK also in an AXIN-dependent manner. In contrast, high concentrations of AMP, arising from severe nutrient stress, activate all pools of AMPK independently of AXIN. Surprisingly, mitochondrion-localized AMPK is activated to phosphorylate ACC2 and mitochondrial fission factor (MFF) only during severe nutrient stress. Our findings reveal a spatiotemporal basis for hierarchical activation of different pools of AMPK during differing degrees of stress severity.

Characteristics of nitrogen and phosphorus adsorption by Mg-loaded biochar from different feedstocks

Herein, biochars from 6 different feedstocks (taro straw, corn straw, cassava straw, Chinese fir straw, banana straw, and Camellia oleifera shell) were produced using magnesium chloride (MgCl₂) as a modifier due to their sorption behavior toward NH₄⁺-N and phosphorus in an aqueous solution. The biochar characteristics were evaluated, including pH, pH_PZC, biochar magnesium content, and total pore volume (PV_tot). The experimental results in terms of the kinetics and equilibrium isotherms showed that the cassava straw and banana straw biochars exhibited the theoretical maximum saturated adsorption capacities of 24.04 mg·g^-1 (NH₄⁺-N) and 31.15 mg·g^-1 (TP), respectively. Biochar produced from these feedstocks had higher magnesium contents and greater total pore volumes, reflecting the significant contributions from magnesium and steric effects. FTIR, XRD, and SEM/EDS analyses demonstrated that NH₄⁺-N and TP sorption mechanisms predominantly involved surface electrostatic attraction, Mg²⁺ precipitates and complexation with surface hydroxyl functional groups.

[Relationship between 25-hydroxyvitamin D levels and idiopathic benign paroxysmal positional vertigo in female patients]

Objective: To investigate the relationship between serum 25-hydroxyvitamin D[25(OH) D] levels and idiopathic benign paroxysmal positional vertigo (BPPV) in female patients. Methods: A total of 67 women diagnosed with idiopathic BPPV were selected as the study group between January and December 2016 in Ningbo No.2 Hospital, and 95 healthy women without a history of vertigo or dizziness were selected as the control group. The data of height, weight, histories of hypertension and diabetes mellitus were collected, and serum 25(OH) D levels were measured. The number of the recurrence and canalith repositioning maneuvers were recorded during the one-year follow-up. Results: No significant differences of age, body mass index, histories of hypertension and diabetes mellitus between patients with BPPV and healthy controls (all P>0.05) .The serum 25 (OH) D levels were significantly lower in patients with idiopathic BPPV than in healthy controls [(50.56±13.36) nmol/L vs (56.55±16.21) nmol/L, t=-2.485, P=0.014]. BPPV patients with low level of 25(OH) D showed a significant increase in the number of canalith repositioning maneuvers required and the recurrence rate. The regression analyses demonstrated that 25(OH)D deficiency was associated with BPPV with an odds ratio of 2.054 (95% CI: 1.088-3.877, P=0.026). Conclusion: 25(OH) D deficiency may be a risk factor of BPPV.

[Relationship between FGF23/FGFR4 expression in atrial tissue and atrial fibrosis in patients with atrial fibrillation]

Objective: To observe the expression of fibroblast growth factor 23 (FGF23) and FGFR4 in patients with atrial fibrillation (AF) and its relationship with atrial fibrosis. Methods: Fifty-one patients with rheumatic heart disease undergoing cardiac surgery at the Second Affiliated Hospital of Nanchang University from October 2016 to April 2017 were divided into two groups according to whether they were complicated with atrial fibrillation: 39 patients with persistent AF(AF group), and 12 patients with sinus rhythm (SR group). The right atrial appendage was cut out during cardiac surgery. The expression of FGF23 and FGFR4 mRNA was detected by quantitative real-time PCR. The expression of FGFR4 protein was detected by Western blot. Atrial structure was evaluated by echocardiography. Masson staining was used to evaluate the degree of atrial fibrosis. The expression of FGF23 and FGFR4 was compared between the two groups.Additionally, the relationship between FGF23 and FGFR4 expression and atrial fibrosis was evaluated. Results: AF group had significantly higher right and left atrial diameter than SR group((40.1±1.6 )mm vs (34.1±1.5)mm, (52.4±2.9)mm vs (41.3±2.4)mm, all P<0.05) . There were no statistically significant differences in age, gender, ejection fraction between the two groups. The expression of FGF23 and FGFR4 mRNA in AF group were significantly higher than those in SR group (1.93±0.32 vs 0.93±0.14, 1.89±0.17 vs 0.91±0.11, both P<0.05). Compared with the SR group, the protein expression of FGFR4 in the AF group was significantly higher(1.76±0.21 vs 0.84±0.12). In AF group, there was no correlation between FGF23 mRNA and atrial diameter (r=0.274 (left atrial), r=0.238 (right atrium), both P>0.05). Meanwhile, FGFR4 mRNA and protein expression had no correlation with atrial diameter either. There was positive correlation between FGF23 mRNA and atrial collagen volume fraction in AF group (r=0.42, P<0.05). The expression of FGFR4 mRNA and protein were positively correlated with the atrial collagen volume fraction (r=0.573, r=0.478, all P<0.05). Conclusion: The expression of FGF23 and FGFR4 in atrial fibrillation patients is increased, which is positively correlated with atrial fibrosis, suggesting that FGF23/FGFR4 pathway may play an important role in atrial fibrillation by promoting atrial fibrosis.

[Prevalence and influential factors of stroke in Jiangxi Province in 2014]

Objective: To discuss the prevalence and influential factors of stroke among population in Jiangxi Province. Methods: Four cities in urban areas and four counties in rural areas were selected firstly, in which two districts or townships were selected; and then three communities or villages were chosen from each district and township, respectively, using the simple random sampling (SRS) method. Finally 15 269 subjects aging 15 years old or above, living in Jiangxi Province ≥6 months were randomly selected to participate in this survey from November 2013 to August 2014. Information of population characteristics, life behavior way, individual disease history were collected through questionnaire survey, and height, weight, waist circumference, blood pressure, body fat rate, visceral fat index and so on were measured by instruments. Risk factors of stroke prevalence were analyzed by the unconditioned logistic regression analysis. Results: A total of 15 269 participants (6 267 males) from 15 364 eligible participants were included in the statistical analysis. Out of which, 7 793 participants came from urban areas, and their average age was (53.04±17.91) years old. In this study, 226 stroke patients (117 males) were found among15 269 participants, including 122 urban participants and 104 rural participants, whose average age was (67.76±9.74) years old. The prevalence of stroke was 1 480.12/100 000 in 2014, which was separately 1 866.92/100 000 and 1 210.84/100 000 among males and females. The prevalence of people aging (45-49) years old was 413.79/100 000 (6/1 450) , while which among people aging 75 years old and above was 3 311.62/100 000 (61/1 842) . The prevalence of stroke among residents in Jiangxi presented an uprising tendency with age increasing (linear-by-linear association χ(2)=62.23, P<0.01). The research showed that when other influencing factors including gender, BMI, waist circumference, pulse-pressure difference, VAI, and sleeping time in non-working days were controlled, hypertensive patients had a higher risk of stroke than people without hypertension (OR=6.88, 95%CI: 4.90-9.67), drinkers had a higher risk of stroke than non-drinkers (OR=1.56, 95%CI: 1.17-2.08), compared with people <65 years old, people aged 65-74 years old and ≥75 years old had a higher risk of stroke, the value of OR (95%CI) were 1.88 (1.36-2.59) and 1.97 (1.39-2.80), respectively, compared with people with normal body fat percentage, people whose body fat percentage on high side and people who with high body fat percentage had a higher risk of stroke, the value of OR (95%CI) were 1.71 (1.18-2.48) and 1.74 (1.18-2.56), respectively, people with sleep time >8 h had a higher risk of stroke than those with sleep time of 6-8 h. Conclusion: There was a high stroke prevalence among residents in Jiangxi province. Hypertension, drinking, age, BFP and sleep duration were associated with stroke prevalence. Corresponding measures for high-risk population and risk factors should be strengthened to prevent and control the stroke.

[Progress in research of family-based cohort study on common chronic non-communicable diseases in rural population in northern China]

Family-based cohort study is a special type of study design, in which biological samples and environmental exposure information of the member in a family are collected and related follow up is conducted. Family-based cohort study can be applied to explore the effect of genetic factors, environmental factors, gene-gene interaction, and gene-environment interaction in the etiology of complex diseases. This paper summarizes the objectives, methods and results, as well as the opportunities and challenges of the family-based cohort study on common chronic non-communicable diseases in rural population in northern China.