Capturing RAS oligomerization on a membrane.

RAS GTPases associate with the biological membrane where they function as molecular switches to regulate cell growth. Recent studies indicate that RAS proteins oligomerize on membranes, and disrupting these assemblies represents an alternative therapeutic strategy. However, conflicting reports on RAS assemblies, ranging in size from dimers to nanoclusters, have brought to the fore key questions regarding the stoichiometry and parameters that influence oligomerization. Here, we probe three isoforms of RAS [Kirsten Rat Sarcoma viral oncogene (KRAS), Harvey Rat Sarcoma viral oncogene (HRAS), and Neuroblastoma oncogene (NRAS)] directly from membranes using mass spectrometry. We show that KRAS on membranes in the inactive state (GDP-bound) is monomeric but forms dimers in the active state (GTP-bound). We demonstrate that the small molecule BI2852 can induce dimerization of KRAS, whereas the binding of effector proteins disrupts dimerization. We also show that RAS dimerization is dependent on lipid composition and reveal that oligomerization of NRAS is regulated by palmitoylation. By monitoring the intrinsic GTPase activity of RAS, we capture the emergence of a dimer containing either mixed nucleotides or GDP on membranes. We find that the interaction of RAS with the catalytic domain of Son of Sevenless (SOScat) is influenced by membrane composition. We also capture the activation and monomer to dimer conversion of KRAS by SOScat. These results not only reveal the stoichiometry of RAS assemblies on membranes but also uncover the impact of critical factors on oligomerization, encompassing regulation by nucleotides, lipids, and palmitoylation.

CDK actively contributes to establishment of the stationary phase state in fission yeast.

Upon exhaustion of essential environmental nutrients, unicellular organisms cease cell division and enter stationary phase, a metabolically repressed state essential for cell survival in stressful environments. In the fission yeast Schizosaccharomyces pombe, cell size is reduced by cell division before entry into stationary phase; thus cyclin-dependent kinase (CDK) must actively contribute to stationary phase establishment. However, the contribution of CDK to stationary phase remains largely uncharacterized. Here, we examine the role of the sole S. pombe CDK, Cdc2, in the establishment of stationary phase. We show that in stationary phase, nuclear and chromosomal volumes and the nucleus-to-cell volume ratio are reduced, and sister chromatid separation and chromosome fluctuation are repressed. Furthermore, Cdc2 accumulates in the nucleolus. Most of these changes are induced by glucose depletion. Reduction in Cdc2 activity before and upon stationary phase entry alleviates the changes and shortens the survival time of stationary phase cells, whereas Cdc2 inhibition represses nucleolar Cdc2 accumulation and glucose depletion-induced nuclear volume reduction. These results demonstrate that CDK actively regulates stationary phase, both before and upon stationary phase entry.

SIRT1: An Intermediator of Key Pathways Regulating Pulmonary Diseases.

Silent information regulator type-1 (SIRT1), a nicotinamide adenine dinucleotide+-dependent deacetylase, is a member of the sirtuins family and has unique protein deacetylase activity. SIRT1 participates in physiological as well as pathophysiological processes by targeting a wide range of protein substrates and signalings. In this review, we described the latest progress of SIRT1 in pulmonary diseases. We have introduced the basic information and summarized the prominent role of SIRT1 in several lung diseases, such as acute lung injury, acute respiratory distress syndrome, chronic obstructive pulmonary disease, lung cancer, and aging-related diseases.

Rapid Sample Pretreatment Facilitating SERS Detection of Trace Weak Organic Acids/Bases in Complex Matrices.

Fast and efficient sample pretreatment is the prerequisite for realizing surface-enhanced Raman spectroscopy (SERS) detection of trace targets in complex matrices, which is still a big issue for the practical application of SERS. Recently, we have proposed a highly performed liquid-liquid extraction (LLE)-back extraction (BE) for weak acids/bases extraction in drinking water and beverage samples. However, the performance efficiency decreased drastically on facing matrices like food and biological blood. Based on the total interaction energies among target, interferent, and extractant molecules, solid-phase extraction (SPE) with a higher selectivity was introduced in advance of LLE-BE, which enabled the sensitive (µg L-1 level) and rapid (within 10 min) SERS detection of both koumine (a weak base) and celastrol (a weak acid) in different food and biological samples. Further, the high SERS sensitivity was determined unmanned by Vis-CAD (a machine learning algorithm), instead of the highly demanded expert recognition. The generality of SPE-LLE-BE for various weak acids/bases (2 < pKa < 12), accompanied by the high efficiency, easy operation, and low cost, offers SERS as a powerful on-site and efficient inspection tool in food safety and forensics.

Effective bandgap narrowing and enhanced optoelectronic performance of Cs2PtBr6 double perovskites by pressure engineering.

Tuning the structure-property relations of perovskites by pressure engineering holds great promise for discovering materials with favorable properties. The newly synthesized Cs2PtBr6 double perovskite exhibits excellent water resistance and chemical stability. Yet its photoelectric conversion efficiency is limited by its intrinsic wide-bandgap nature. In this work, based on density functional theory calculations, we demonstrate the bandgap narrowing of Cs2PtBr6 via pressure engineering and maintain its structural stability. Strikingly, upon applying pressure up to 12 GPa, the bandgap value decreases to 1.34 eV, which exactly reaches the optimal bandgap required by the Shockley-Queisser efficiency limit. Moreover, optical calculation analysis shows that the optical absorption of Cs2PtBr6 exhibits a significant improvement within the visible range. Therefore, the potential of Cs2PtBr6 as a photovoltaic material by pressure engineering is improved. This work is useful for designing and synthesizing new perovskite materials with enhanced performance.

A new method to estimate the histological stage of primary biliary cholangitis.

OBJECTIVE: To analyze the diagnostic efficacy of the periportal hypoechoic band (PHB) in the histological stage of patients with primary biliary cholangitis (PBC). METHODS: We prospectively included 77 cases of PBC pathologically or clinically confirmed, and high-frequency ultrasound (HFUS) measurements of the PHB were performed in all included patients. Ludwig staging system of histopathology was used as the gold standard. RESULTS: The width of the PHB was positively correlated with histological staging (r = 0.844, p < 0.001). By area under the receiving operating characteristic curve (AUROC), the best cutoff value for PHB for advanced stage (≥ stage 3) was 2.4 mm (AUROC: 0.934; 95%CI: 0.841-0.981) and 0.93 for sensitivity, and 0.91 for specificity, the concordance rates of PHB vs. liver biopsy was 90.3%. The correct rate for early-stage PBC was 87.9% and for the progressive stage was 93.1%. After multi-factor regression analysis, the PHB (OR = 1.331, CI = 1.105-1.603, p = 0.003) and total bilirubin (OR = 1.156, CI = 1.041-1.285, p = 0.007) were independent influencing factors for progressive PBC. CONCLUSIONS: Measurement of the PHB to assess advanced PBC is a simple and effective method. This method may complement current methods for the histological staging assessment of patients with PBC. REGISTRATION: Clinical trial registration: ChiCTR 2000032053, 2020/04/19. CLINICAL RELEVANCE STATEMENT: The measurement of periportal hypoechoic band (PHB) provides a simple and easy assessment of the degree of disease progression in patients with PBC and provides an important clinical reference in predicting the histological staging of PBC from an ultrasound perspective. KEY POINTS: • The PHB is correlated with histological staging in the patient with PBC. • The area under the ROC curves of PHB for detecting advanced stage (≥ stage 3) were 0.934 and 0.93 for sensitivity, and 0.91 for specificity, the concordance rates of PHB vs. liver biopsy was 90.3%. The application of PHB can better assess the advanced PBC. • Measurement of the PHB to assess advanced PBC is a simple and effective method that can significantly reduce the need for liver biopsy.

Non-invasive assessment of esophageal and fundic varices in patients with primary biliary cholangitis.

OBJECTIVES: The Baveno VII consensus recommends endoscopic screening for varicose veins in cases of liver stiffness measurement (LSM) ≥ 20 kPa or platelet count ≤ 150 × 109/L. Whether this approach was appropriate for patients with primary biliary cholangitis (PBC) remains uncertain. This study expanded the observed risk factors by adding analysis of ultrasound images as a non-invasive tool to predict the risk of esophageal or fundic varices. METHODS: We enrolled 111 patients with PBC whose complete ultrasound images, measurement data, and LSM data were available. The value of the periportal hypoechoic band (PHB), splenic area, and LSM in determining the risk of varicose veins and variceal rupture was analyzed. A prospective cohort of 67 patients provided external validation. RESULTS: The area under the receiver operating characteristic curve (AUC) for predicting varicose veins using LSM > 12.1 kPa or splenic areas > 41.2 cm2 was 0.806 (95% confidence interval (CI): 0.720-0.875) and 0.852 (95% CI: 0.772-0.912), respectively. This finding could assist in avoiding endoscopic screening by 76.6% and 83.8%, respectively, with diagnostic accuracy surpassing that suggested by Baveno VII guidelines. The AUCs for predicting variceal rupture using splenic areas > 56.8 cm2 was 0.717 (95% CI: 0.623-0.798). The diagnostic accuracy of PHB for variceal rupture was higher than LSM and splenic areas (75.7% vs. 50.5% vs. 68.5%). CONCLUSION: We recommend LSM > 12.1 kPa as a cutoff value to predict the risk of varicosity presence in patients with PBC. Additionally, the splenic area demonstrated high accuracy and relevance for predicting varicose veins and variceal rupture, respectively. The method is simple and reproducible, allowing endoscopy to be safely avoided. CLINICAL RELEVANCE STATEMENT: The measurement of the splenic area and identification of the periportal hypoechoic band (PHB) on ultrasound demonstrated high accuracy and relevance for predicting the risk of esophageal or fundic varices presence and variceal rupture, respectively. KEY POINTS: Predicting varices in patients with primary biliary cholangitis (PBC) can reduce the morbidity and mortality of gastrointestinal hemorrhage. Transient elastography (TE) and ultrasound play an important role in predicting patients with PBC with varices. TE and ultrasound can predict varicose veins and variceal rupture. Liver stiffness measurement and splenic area measurements can allow endoscopy to be safely avoided.

Identification, molecular profiling and immune functions of cystatin M in silver pomfret (Pampus argenteus).

Cystatins play an important role in various physiological and pathological processes of organisms, including regulating protein metabolism, antigen processing, inflammatory response, nutritional disorders, and controlling enzyme activity. However, research on immunity functions of fish cystatin M is limited. In this study, Pampus argenteus cystatin M (Pacystatin M) was identified and analyzed. Its amino acid sequence was highly conserved in teleosts, and included the conserved cystatin cysteine protease inhibitor motifs. Pacystatin M was highly expressed in the gill, spleen, and intestine, whereas the expression levels of liver and kidney were lower. Furthermore, Nocardia seriolae infection up-regulated the expression of Pacystatin M in the kidney, spleen and liver, with particularly significant expression observed in the liver on day 15 post-infection. Functional analysis indicated that the recombinant Pacystatin M showed increasing inhibitory activity against papain within a certain concentration range, suggesting that the inhibition was likely competitive. Additionally, Pacystatin M demonstrated the ability to inhibit bacterial growth and high thermal stability. These results suggested that Pacystatin M might be involved in the immune response to microbial invasion and provided new reference addressing disease issues in the large-scale farming of silver pomfret.

Effects of vitamins and polyunsaturated fatty acids on cognitive function in older adults with mild cognitive impairment: a meta-analysis of randomized controlled trials.

PURPOSE: Vitamins and polyunsaturated fatty acids (PUFAs) have been studied extensively as safe and manageable nutrient interventions for mild cognitive impairment (MCI). The purpose of the current meta-analysis was to examine the effects of vitamins and PUFAs on cognition and to compare the effects of single and multiple nutrient subgroups in patients with MCI. METHODS: Randomized controlled trials (RCTs) written in English and Chinese were retrieved from eight databases, namely, PubMed, CENTRAL, Embase, CINAHL, Web of Science, SinoMed, CNKI, and Wanfang Data, from their respective dates of inception until 16 July 2023. The quality of the included studies was assessed using the Cochrane Risk of Bias Tool 2.0. Meta-analyses were performed to determine the standardized mean differences (SMDs) in global cognitive function, memory function, attention, visuospatial skills, executive function, and processing speed between the supplement and control groups using 95% confidence intervals (CI) and I2. Prospero registration number: CRD42021292360. RESULTS: Sixteen RCTs that studied different types of vitamins and PUFAs were included. The meta-analysis revealed that vitamins affected global cognitive function (SMD = 0.58, 95% CI = [0.20, 0.96], P = 0.003), memory function (SMD = 2.55, 95% CI = [1.01, 4.09], P = 0.001), and attention (SMD = 3.14, 95% CI = [1.00, 5.28], P = 0.004) in patients with MCI, and PUFAs showed effects on memory function (SMD = 0.65, 95% CI = [0.32, 0.99], P < 0.001) and attention (SMD = 2.98, 95% CI = [2.11, 3.84], P < 0.001). Single vitamin B (folic acid [FA]: SMD = 1.21, 95% CI = [0.87, 1.55]) supplementation may be more effective than multiple nutrients (FA and vitamin B12: SMD = 0.71, 95% CI = [0.41, 1.01]; and FA combined with docosahexaenoic acid [DHA]: SMD = 0.58, 95% CI = [0.34, 0.83]) in global cognitive function. CONCLUSIONS: FA, vitamin B6, vitamin B12, and vitamin D may improve global cognitive function, memory function, and attention in patients with MCI. Eicosapentaenoic acid (EPA) and DHA may improve memory function and attention. We also noted that FA may exert a greater effect than a vitamin B combination (FA and vitamin B12) or the combination of FA and DHA. However, because of the low evidence-based intensity, further trials are necessary to confirm these findings.

Research Progress on Cognitive Frailty in Older Adults with Chronic Kidney Disease.

BACKGROUND: As the medical challenges posed by the ageing population become increasingly severe, the proportion of older people among patients with chronic kidney disease (CKD) is increasing every year. SUMMARY: The prevalence of frailty in patients with CKD is significantly higher than that in the general population, and older patients are also a high-risk group for frailty and cognitive impairment. Cognitive frailty, as an important subtype of frailty, is a syndrome characterised by cognitive dysfunction caused by physiological factors, excluding Alzheimer's disease and other types of dementia. It is characterised by the coexistence of physical frailty and cognitive impairment. Previous studies have mainly focused on cognitive impairment, and there is limited research on cognitive frailty, particularly in older patients with CKD. KEY MESSAGES: This article provides a comprehensive review of the concept, epidemiology, screening methods, prevention, and treatment measures and possible pathogenesis of cognitive frailty in patients with CKD.

Circ-Luc7l Absence Attenuates Diabetic Nephropathy Progression by Reducing Mesangial Cell Excessive Proliferation, Inflammation, and Extracellular Matrix Accumulation via Mediating the miR-205-5p/Tgfbr1 Pathway.

Diabetic nephropathy (DN) threatens the survival quality of patients, with complex pathogenesis. Circular RNA (circRNA) dysregulation occurs in DN development. This work aimed to investigate the role of circ-Luc7l in DN cell models and related molecular mechanisms. The expression of circ-Luc7l, microRNA (miR)-205-5p, and transforming growth factor-beta receptor 1 (Tgfbr1) was examined by real-time quantitative PCR (RT-qPCR). Cell viability and proliferation were detected by Cell Counting Kit-8 (CCK-8) assay and EdU assay. The expression of extracellular matrix (ECM)-related markers and Tgrbr1 protein was measured by Western blot. The binding between miR-205-5p and circ-Luc7l or Tgfbr1 was validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, or RNA pull-down assay. Experimental animal models were established to elucidate the function of circ-Luc7l in vivo. Circ-Luc7l expression was notably enhanced in high glucose (HG)-treated mesangial cells. Knockdown of circ-Luc7l attenuated HG-induced cell proliferation, inflammation, and ECM accumulation in vitro and relieved inflammation and ECM accumulation of kidneys of diabetic mice in vivo. Circ-Luc7l targeted miR-205-5p, and miR-205-5p inhibition rescued the depletion effects of circ-Luc7l knockdown on cell proliferation, inflammation, and ECM accumulation. MiR-205-5p bound to Tgfbr1 whose expression was negatively regulated by circ-Luc7l. Tgfbr1 overexpression also rescued the depletion effects of circ-Luc7l knockdown on cell proliferation, inflammation, and ECM accumulation. In HG conditions, increased circ-Luc7l upregulated Tgfbr1 expression via targeting miR-205-5p to induce DN progression.

Safety and efficacy of bilateral superselective adrenal arterial embolization for treatment of idiopathic hyperaldosteronism: a prospective single-center study.

OBJECTIVE: This study aimed to assess the efficacy and safety of bilateral superselective adrenal arterial embolization (SAAE) in patients with bilateral idiopathic hyperaldosteronism (IHA), a subtype of PA. METHODS: Ninety-eight patients with bilateral IHA underwent bilateral SAAE between August 2022 and August 2023. Sixty-eight patients were followed up for up to 12 months. The study outcomes were evaluated using the criteria provided by the Primary Aldosteronism Surgical Outcome (PASO) guidelines. RESULTS: The mean reductions in systolic and diastolic blood pressure were 27.4 ± 21.3 mmHg and 23.1 ± 17.4 mmHg, respectively (p < 0.001). The rates of clinical success and biochemical success after adrenal artery ablation were 63.2% (43/68) and 39.7% (27/68), respectively. Overall, there were significant reductions in daily defined doses (DDD), aldosterone/renin ratio (ARR), and plasma aldosterone levels (p < 0.001). Plasma renin levels increased by a mean value of 10.4 ± 39.0 pg/mL (p = 0.049), and potassium levels increased by 0.40 ± 0.63 mmol/L (p < 0.001). No significant adverse events were reported during SAAE or the follow-up period of up to one year. Additionally, no abnormalities were detected by adrenal 68Ga-Pentixafor PET/CT scans before or after SAAE. CONCLUSION: Bilateral SAAE appears to lead to sustained improvements in blood pressure and biochemical parameters in patients with bilateral PA, with minimal adverse effects. This suggests that bilateral SAAE could serve as an effective alternative approach for treating bilateral IHA, potentially curing this condition.

Multi-Scale Attention Network for Building Extraction from High-Resolution Remote Sensing Images.

The precise building extraction from high-resolution remote sensing images holds significant application for urban planning, resource management, and environmental conservation. In recent years, deep neural networks (DNNs) have garnered substantial attention for their adeptness in learning and extracting features, becoming integral to building extraction methodologies and yielding noteworthy performance outcomes. Nonetheless, prevailing DNN-based models for building extraction often overlook spatial information during the feature extraction phase. Additionally, many existing models employ a simplistic and direct approach in the feature fusion stage, potentially leading to spurious target detection and the amplification of internal noise. To address these concerns, we present a multi-scale attention network (MSANet) tailored for building extraction from high-resolution remote sensing images. In our approach, we initially extracted multi-scale building feature information, leveraging the multi-scale channel attention mechanism and multi-scale spatial attention mechanism. Subsequently, we employed adaptive hierarchical weighting processes on the extracted building features. Concurrently, we introduced a gating mechanism to facilitate the effective fusion of multi-scale features. The efficacy of the proposed MSANet was evaluated using the WHU aerial image dataset and the WHU satellite image dataset. The experimental results demonstrate compelling performance metrics, with the F1 scores registering at 93.76% and 77.64% on the WHU aerial imagery dataset and WHU satellite dataset II, respectively. Furthermore, the intersection over union (IoU) values stood at 88.25% and 63.46%, surpassing benchmarks set by DeepLabV3 and GSMC.

Design and impact assessment of policies to overcome oversupply in China's national carbon market.

China has adopted a national carbon emissions trading market to promote emission reductions, but until now, overallocation of allowances suffer low carbon prices and thus to unfulfilled emission reduction goals. We report a general equilibrium modeling that indicates the flexible compliance and price adjustment mechanism of the carbon market, along with explores the solution to the oversupply of allowances in the China's national carbon market. We find that, under the current policy, the initial loose allowance allocation decreases the overall carbon price, and simultaneously the total amount of banked carbon allowances reaches 4.880 billion tons in 2030, resulting in the level of carbon price cannot achieve NDC (Nationally Determined Contribution) targets. However, by introducing carbon market price adjustment schemes, we observe that the cumulative amount of allowances can effectively reduce, enabling the carbon price rising. Importantly, the amount of the supply of allowances decreases most under the benchmark decrease scenario, which increases the emission reduction pressure of the enterprises from the beginning, leading to the largest economic losses, the price-based adjustment mechanism raises the carbon price to expected level at the minimize economic losses, and the quantity-based adjustment mechanism is more sensitive to policy parameters compared to the price -based adjustment mechanism. These findings offer a promising avenue for selecting cost-effective price adjustment mechanism to improve price mechanism design for national carbon markets.

Functional responses of two species of predatory mites (Acari: Phytoseiidae) to eggs and first-instar nymphs of Bactericera Gobica Logniova (Homoptera: Psyllidae).

The goji berry psyllid, Bactericera gobica Logniova (Homoptera: Psyllidae), is one of the most important pests on goji berry plants (Lycium barbarum L.), whose fruits are widely used in traditional Chinese medicine and food. However, chemical control is still the predominant control strategy of this pest. Recently, two species of predatory mites, Neoseiulus setarius Ma, Meng & Fan and Neoseiulus barkeri Hughes were found to be associated with B. gobica in China. To assess their predation potential against B. gobica, the functional responses of these two phytoseiid species feeding on different densities (2, 4, 8, 12, 16, 24 and 32 individuals) of B. gobica eggs and 1st instar nymphs were compared at a temperature of 25ºC ± 1º C. Logistic regression analysis revealed that both predatory mite species exhibited type Holling-II functional responses on eggs and 1st instar nymphs of B. gobica, with the predation number increased for both predators as the density of prey increased. Overall, N. setarius consumed more prey compared to N. barkeri across all levels of prey densities. Meanwhile, the highest attack rate (α = 0.0283), the lowest handling time (Th = 1.1324 h prey- 1), and the highest estimated maximum predation rate (T/Th = 21.19 prey day- 1) were all observed for N. setarius fed with 1st instar nymphs of B. gobica. These findings suggest that it is worthy considering utilizing N. setarius and N. barkeri as candidate biocontrol agents of B. gobica, with N. setarius appearing to be a more effective predator than N. barkeri.

Family cleaning behaviors and air treatment equipment significantly affect associations of indoor damp indicators with childhood pneumonia among preschoolers.

In this study, based on a cross-sectional study among 9597 preschoolers in Shandong of China, we quantitatively evaluated influences of lifestyle behaviors and air treatment equipment on indoor damp exposures and thus on risks of childhood pneumonia. In the two-level multivariate logistic regression analyses, childhood pneumonia was significantly associated with parent-reported damp clothing/bedding and visible mold spots or damp stains. These associations were weaker among preschoolers from families who frequently opened the child's bedroom windows, frequently cleaned the child's bedroom, and frequently exposed beddings to sunshine (references: not frequently), as well as among preschoolers without usage of air humidifier and air conditioner and with usage of air purifier. Our results indicate that frequently keeping household ventilation and cleanness, and exposing beddings to sunshine, as well using air purifier could decrease the effects of household damp-related exposures on childhood pneumonia, but using air humidifier and air conditioner could increase the effects.

Older adults' perceptions and experiences of engaging in web- and mobile-based physical activity interventions: A systematic review and qualitative meta-synthesis.

BACKGROUND: Web- and mobile-based physical activity interventions effectively promote physical and mental health among older adults, but participation and adherence are suboptimal. METHODS: This qualitative review used the mega-aggregation approach. Searches were conducted in five databases from the earliest to November 2023. Quality assessment and data extraction used JBI tools. Data synthesis used the COM-B model as a guide. RESULTS: Sixteen sub-themes were identified from the eight studies and categorized into the COM-B model. Sub­themes were physical and psychological changes, digital skills and knowledge, older adult-friendly design, integration into daily routines, social influence, family engagement and support, health benefits and impairments, accessibility and flexibility, low cost, visibility and interaction, instructions and feedback, personalization and progression, incentives, self-efficacy, visual cues, self-monitoring. DISCUSSION: Web- and mobile-based interventions motivate older adults to engage in physical activity, but modifications are necessary. This includes age-appropriate interfaces and contents, tailored behavioral change techniques, and family engagement.

[Effect of Using Hydrogen Peroxide for Periodic Disinfection Combined With Continuous Disinfection to Control Contamination in Dental Unit Waterline]. / è¿‡æ°§åŒ–æ°¢å®šæœŸæ¶ˆæ¯’ç»“åˆæŒç»­æ¶ˆæ¯’å¯¹å£è ”ç»¼åˆæ²»ç–—å°æ°´è·¯æ±¡æŸ“æŽ§åˆ¶çš„æœ‰æ•ˆæ€§è§‚å¯Ÿ.

Objective: To observe the effect of using hydrogen peroxide in periodic disinfection combining with continuous disinfection of dental unit waterlines and to provide references for the selection of waterway disinfection measures. Methods: A total of 4 dental units in a hospital of stomatology were selected through convenience sampling. The dental unit waterlines received periodic disinfection once every 4 weeks in addition to continuous disinfection (When the dental units were not used for more than 3 days, an additional periodic disinfection would be performed.). Periodic disinfection referred to filling up the waterlines with a disinfectant solution (1.4% hydrogen peroxide) by using the waterline disinfection device that came with the dental unit, immersing for 24 hours, and then emptying out the disinfectant solution. Continuous disinfection referred to using hydrogen peroxide at a concentration of 0.014% as dental treatment water and using it to flush the waterlines for 2 minutes before any dental treatment in the morning and to flush the waterlines for 30 seconds after each dental treatment. The study lasted for 25 weeks, with periodic disinfection being performed for 7 times and continuous disinfection carried out for the rest of the dental treatment time. During the 25 weeks, water samples were collected from air/water syringes and high-speed handpieces. Then, the water samples were incubated and the bacterial concentration and the qualification rates were calculated accordingly. When the bacterial concentration≤100 CFU/ mL, the water samples were considered to be qualified. Waterline tubes of 1 cm were collected before and after the 25 weeks of disinfection with hydrogen peroxide. Biofilms in the waterline tube were observed under scanning electron microscope. Results: A total of 352 water samples were collected. Eight water samples were collected before disinfection with hydrogen peroxide, with the median of bacterial concentration being 3140 CFU/mL. On the first day of disinfection with hydrogen peroxide, the median bacterial concentration in dental treatment water was 7.5 CFU/mL. There was a significant difference between the bacterial concentration of the water samples before the disinfection and that after the disinfection (P=0.012). A total of 344 water samples were collected after the disinfection, with the median bacterial concentrations for air/water syringes and high-speed handpieces being 11 CFU/mL and 11CFU/mL and the qualified rates being 83.7% and 82.0%, respectively. There was no significant difference in bacterial concentration or the qualification rates. During week 1 through week 9 of the disinfection, the qualification rates of the dental treatment water always exceeded 80% in 8 weeks, with week 3 being the exception. In the two four-week disinfection periods of week 14 through week 17 and week 18 through week 21, the qualification rate was maintained at above 80% for only the first two weeks and started to decrease from the third week. Biofilm morphology was observed under scanning electron microscope. Before the disinfection, the biofilm was found to be a dense structure and the mixture of a large number of bacteria. After 25 weeks of the disinfection, the biofilm structure appeared to be loose and did not show consistent characteristics of a large number of bacteria retained. Conclusion: Periodic disinfection combined with continuous disinfection using hydrogen peroxide can effectively control contamination in dental unit waterlines. But the cycles of periodic disinfection and the concentration of hydrogen peroxide for continuous disinfection should be further discussed according to the actual clinical situation.

PRMT5 activates KLF5 by methylation to facilitate lung cancer.

The highly expressed oncogenic factor Krüppel-like factor 5 (KLF5) promotes various cancerous processes, such as cell growth, survival, anti-apoptosis, migration and metastasis, particularly in lung cancer. Nevertheless, the modifications to KLF5 after translation are poorly understood. Protein arginine methyltransferase 5 (PRMT5) is considered as an oncogene known to be involved in different types of carcinomas, including lung cancer. Here, we show that the expression levels of PRMT5 and KLF5 are highly expressed lung cancer. Moreover, PRMT5 interacts with KLF5 and facilitates the dimethylation of KLF5 at Arginine 41 in a manner that depends on methyltransferase activity. Downregulation or pharmaceutical suppression of PRMT5 reduces the expression of KLF5 and its downstream targets both in vitro and in vivo. Mechanistically, the dimethylation of KLF5 by PRMT5 promotes the maintenance and proliferation of lung cancer cells at least partially by stabilising KLF5 via regulation of the Akt/GSK3ß signalling axis. In summary, PRMT5 methylates KLF5 to prevent its degradation, thereby promoting the maintenance and proliferation of lung cancer cells. These results suggest that targeting PRMT5/KLF5 axis may offer a potential therapeutic strategy for lung cancer.

Oxygenated Triazine-Heptazine Heterostructure Creates an Enormous Ascension to the Visible Light Photocatalytic Hydrogen Evolution Performance of Porous C3 N4 Nanosheets.

A highly efficient g-C3 N4 photocatalyst is developed by a novel one-pot thermal polymerization method under a salt fog environment generated by heating the aqueous solution of urea and mixed metal salts of NaCl/KCl, namely SF-CN. Thanks to the synergistic effect of the oxygenation and chemical etching of the salt fog, the obtained SF-CN is an oxygenated ultrathin porous carbon nitride with an intermolecular triazine-heptazine heterostructure, meanwhile, shows enlarged specific surface area, greatly enhanced absorption of visible light, narrowed band gap with a lower conduction band, and an increased photocurrent response due to the effective separation of photogenerated holes and electrons, comparing to those of pristine g-C3 N4 . The theoretical simulations further reveal that the triazine-heptazine heterostructure possesses better photocatalytic hydrogen evolution (PHE) capability than pure triazine and heptazine carbon nitrides. In turn, SF-CN demonstrates an excellent visible light PHE rate of 18.13 mmol h-1  g-1 , up to 259.00 times of that of pristine g-C3 N4 .