Objective: To observe the effect of electroacupuncture (EA) on cytochrome c oxidase (COX)activity of hippocampal mitochondria in senescence-accelerated mouse prone 8 (SAMP8) mice, and to explore the EA mechanism on Alzheimer disease (AD) in improving energy metabolic disorder.
Methods: Twelve SAMP8 mice were randomly divided into a model group and an EA group, with six in each group. Six senescence-accelerated mouse resistance 1 (SAMR1) mice were prepared as blank group. Mice in the EA group received EA on Baihui (GV 20) and Yongquan (KI 1), once a day for 7 d as a course, altogether 3 courses with one day intervalbetween two courses. Mice in the model group and the blank group were manipulated and fixed as those in the EA group. After interventions, Morris water maze was employed to test spatial learning and memory ability to evaluate EA effect; spectrophotometry was used to detect the activity of hippocampal mitochondria COX.
Results: Compared with the blank group, mean escape latenciesof the EA group and model group were prolonged significantly in Morris water maze tests (P<0.01), the residue duration in the former platform quadrant significantly decreased (P<0.01). Compared with the model group, mean escape latencies on 1 d, 2 d and 3 d of the EA group were significantly reduced (P<0.05), and those on 4 d and 5 d continued the decreasing tendency (P<0.01), the residue duration on the former platform quadrant was significantly prolonged (P<0.05). The COX activity tests showed that, compared with the blank group, COX activities of the model group and the EA group were significantly decreased (P<0.01); compared with the model group, COX activity of the EA group was significantly elevated (P<0.01).
Conclusion: It’s plausible that EA improves AD learning and memory ability by increasing mitochondria COX activity, protecting the structure and function, and improving energy metabolism.

Objective To prepare simulated stool specimens for proficiency testing ( PT) by mix-ing lentils with Salmonella, Shigella and Escherichia coli strains and to establish an assessment scheme for the detection of Salmonella and Shigella in clinical samples. Methods Salmonella, Shigella and Escherich-ia coli strains were respectively spiked to lentils in Cary-Blair transport medium to create simulated stool specimens. Various ratios of Escherichia coli to Salmonella strains were spiked to lentils to prepare mixed simulated stool specimens. The accuracy and stability of prepared stool samples for PT were tested in-house. Results of sample detection were collected from participating laboratories for further external quality assess-ment. Results The Escherichia coli and Salmonella strains mixed at ratios of 100 ∶ 1 to 106 ∶ 1 could be ef-ficiently isolated from the media. Enrichment was needed in order to effectively isolate Salmonella strains from the media when the ratios of Escherichia coli to Salmonella strains were 104 ∶ 1 to 106 ∶ 1. Of the16 participating laboratories, 14 laboratories (87. 5%) received a grade of“satisfactory” and the other 2 labo-ratories (12. 5%) received a grade of “mainly satisfactory”. Conclusion The simulated stool specimens and the PT procedures designed in this study were suitable for proficiency testing program on the detection of Salmonella, Shigella and other similar microbes.

Objective To analyze the serotype distribution and antibiotic resistance characteristics of Salmonella strains isolated in Guangdong province for better understanding the condition of Salmonella infection in patients with diarrhea.Methods Fecal samples collected from patients with diarrhea in Guangdong province were used to isolate Salmonella strains.Biochemical analysis was performed to identify these isolated strains.Serotyping and antimicrobial susceptibility testing were carried out for further analysis of the isolated Salmonella strains.Results The rate of Salmonella infection was 7.64％in 2015, and the male to female patient ratio was 1.52∶1.A total of 2 377 patients of all age groups were positive for Salmonella infection and the patients aged 0-6 years accounted for 81.74％.The isolation rate of Salmonella strains in the summer and autumn was higher than that in the winter and spring (10.73％ vs 4.24％;X2=463.77, P<0.01).The Salmonella isolation rates in different areas were as follows: 16.82％ in Zhuhai, 15.85％ in Heyuan, 11.81％ in Yangjiang, 10.68％ in Jiangmen, 8.49％ in Zhongshan, 8.07％ in Maoming, 8.05％ in Jieyang, 7.35％ in Shaoguan, 6.97％ in Foshan, 6.03％ in Dongguan, 5.48％ in Guangzhou and 0.00％ in Zhanjiang.And the differences between different regions were statistically significant (X2=367.67, P<0.01).The 2 377 isolated Salmonella strains were classified into 108 serotypes except for oneSalmonella strain that could not be classified.The top four predominant serotypes were 4,5,12:i:-, Salmonella enteritidis,Salmonella stanley and Salmonella typhimurium.Most Salmonella strains were sensitive to imipenem, azithromycin, ceftazidime, cefotaxime and trimethoprim/sulfamethoxazole, but multidrug resistance was common among those strains.Conclusion Salmonella serotypes of 4,5,12:i:-and Salmonella enteritidis are the predominant pathogens causing human Salmonella infections in Guangdong province.Ceftazidime and cefotaximeare are preferred in the treatment of Salmonella infections.Surveillance for drug resistance in Salmonella should be strengthened as multidrug resistant strains have become a serious problem in Guangdong province.

The Rad1 gene is evolutionarily conserved from yeast to human. The fission yeast Schizosaccharomyces pombe Rad1 ortholog promotes cell survival against DNA damage and is required for G(2)/M checkpoint activation. In this study, mouse embryonic stem (ES) cells with a targeted deletion of Mrad1, the mouse ortholog of this gene, were created to evaluate its function in mammalian cells. Mrad1 (-/-) ES cells were highly sensitive to ultraviolet-light (UV light), hydroxyurea (HU) and gamma rays, and were defective in G(2)/M as well as S/M checkpoints. These data indicate that Mrad1 is required for repairing DNA lesions induced by UV-light, HU and gamma rays, and for mediating G(2)/M and S/M checkpoint controls. We further demonstrated that Mrad1 plays an important role in homologous recombination repair (HRR) in ES cells, but a minor HRR role in differentiated mouse cells.
Animals ; Cell Division ; Cell Proliferation ; DNA Damage ; DNA Repair ; Embryonic Stem Cells ; metabolism ; Exonucleases ; genetics ; metabolism ; physiology ; G2 Phase ; Gamma Rays ; Gene Deletion ; Hydroxyurea ; pharmacology ; Mice ; Ultraviolet Rays

ObjectiveTo explore the effect of prone position ventilation (PPV) on respiratory mechanics and prognosis in patients with acute respiratory distress syndrome (ARDS) concurrent with interstitial lung disease (ILD). Methods The data of 36 severe ARDS patients admitted to Department of Critical Care Medicine of the First Affiliated Hospital of Guangzhou Medical University from February 2013 to January 2015, were retrospectively analyzed. They were then divided into two groups according to the presence of ILD or not. The changes in respiratory mechanics and oxygenation indexes were compared before and after PPV treatment in all the patients. Kaplan-Meier method was applied to draw the 60-day survival curves of both groups.Results There were 17 cases with ILD among these 36 severe ARDS patients.① No significant difference was found in baseline data between ILD group and non-ILD group.② Respiratory mechanics and oxygenation pre-PPV and post-PPV: compared with pre-PPV, oxygenation index (PaO2/FiO2, mmHg, 1 mmHg = 0.133 kPa) post-PPV was significantly increased in both groups [ILD group : 132.0 (93.5, 172.0) vs. 118.7 (92.0, 147.8); non-ILD group: 126.1 (100.9, 170.0) vs. 109.2 (89.0, 135.0), bothP< 0.05]. Compared with pre-PPV, positive end-expiratory pressure (PEEP, cmH2O,1 cmH2O = 0.098kPa) post-PPV was significantly higher in ILD group [10.0 (10.0, 12.0) vs. 10.0 (9.2, 12.0),P< 0.05], and respiratory rate (RR, times/min) was significantly lower in non-ILD group [24.5 (22.0, 27.0) vs. 25.5 (22.8, 28.0),P< 0.05]. The compliance of the respiratory system (Crs, mL/cmH2O) post-PPV in non-ILD group was significantly lower than that of the ILD group [19.7 (16.1, 28.6) vs. 23.0 (19.0, 29.7),P< 0.05].③ Respiratory mechanics and oxygenation pre-PPV and post-PPV in total: after all the PPV therapy, PaO2/FiO2 (mmHg) was significantly increased in non-ILD group [135.0 (86.0, 200.0) vs. 97.4 (69.2, 127.5), P< 0.05], PaO2/FiO2 after all the PPV therapy in non-ILD group was also higher than that in ILD group [135.0 (86.0, 200.0) vs. 78.7 (59.3, 114.9),P< 0.05]. No significant difference in Crs (mL/cmH2O) before PPV treatment was found between non-ILD and ILD groups [24.3 (15.9, 48.9) vs. 18.9 (12.7, 27.3),P> 0.05], and Crs was lower after PPV treatment in both groups, but without significant difference [non-ILD group: 22.7 (15.2, 27.1) vs. 24.3 (15.9, 48.9); ILD group: 16.2 (12.8, 25.6) vs. 18.9 (12.7, 27.3), bothP> 0.05].④ The 60-day mortality in ILD group was significantly higher than that in non-ILD group [88.2% (15/17) vs. 57.9% (11/19),P = 0.047). It was shown by Kaplan-Meier curves that 60-day survival patients in ILD group was significantly lower than those in non-ILD group (χ2 = 5.658,P = 0.017). Conclusions PPV can improve oxygenation in severe ARDS. Compared with non-ILD group, though the compliance of respiratory system in ILD group is increased during PPV, long-term effect is better in non-ILD group.

Objective To investigate the infection status, serotype distribution, drug sensitivity and molecular characteristics of diarrheagenic Escherichia coli (DEC) in patients with diarrhea in Guangdong Province. Methods Fecal samples were collected, cultured and isolated by traditional methods. Suspected Escherichia coli isolates were confirmed by multiplex PCR used for detecting specific virulence genes and bio-chemical methods. Positive strains were serotyped, characterized for drug sensitivity and analyzed by pulsed-field gel electrophoresis ( PFGE). Results The total positive rate of DEC in patients with diarrhea was 6.26%. The positive rates of enteropathogenic Escherichia coli (EPEC), enterotoxigenic Escherichia coli (ETEC), enterohemorrhagic Escherichia coli (EHEC), enteroadherent Escherichia coli (EAEC) and en-teroinvasive Escherichia coli (EIEC) were 2. 47% , 1. 54% , 1. 32% , 0. 62% and 0. 09% , respectively, with infections primarily in children aged 0-<7 years. The total seropositive rate was 52. 54% , with EHEC accounting for 15. 00% . DEC showed high sensitivity to imipenem, ciprofloxacin, ceftazidime and cefo-taxime. The multidrug resistance rate of DEC was 58. 45% , with EPEC being the most serious for multidrug resistance. PFGE results showed that ETEC, EHEC, EPEC and EAEC had a high degree of polymorphism. Conclusion EPEC is the predominant type of DEC circulating in Guangdong Province. Third-generation cephalosporins are the first drugs of choice for treating infections in children. Ciprofloxacin can be used to treat adults. The problem of multiple drug resistance of DEC is severe and efforts to monitor DEC infections and drug resistance should be strengthened.

Objective To investigated the etiologic characteristics of Shigella (S.) sonnei strains causing outbreaks and sporadic cases in some areas of Guangdong province and Guangxi Zhuang Autonomous Region during 2014-2016. Methods Fourteen S. sonnei strains isolated from outbreaks and 6 S. sonnei strains from sporadic cases from Guangdong and Liuzhou of Guangxi Zhuang Autonomous Region were tested for antimicrobial resistance and analyzed by pulsed-field gel electrophoresis (PFGE). Six typical strains were selected for whole genome sequencing typing and compared with 51 strains isolated both at home and abroad from NCBI genome database. Results The antibiotic resistance test indicated the isolates had high resistance rate to ampicillin, tetracycline, gentamicin, trimethoprim/sulfamethoxazole and nalidixic acid, while sensitive to azithromycin, chloromycetin and imipenem. PFGE showed high similarity (93.2%) among the strains isolated from different areas. The whole genome sequencing analysis also revealed that all the typical strains wereclustered into a same evolution branch, close to some strains from Korea. Conclusions The S. sonnei strains isolated from some areas of Guangdong and Guangxi Zhuang Autonomous Region showed high resistance to commonly used antibiotics, but they were sensitive to azithromycin, chloramphenicol and imipenem. The isolates in this study also showed similar PFGE patterns and close phylogenic evolution.

BACKGROUND:Epigenetics,as an important regulation mode of gene expression network,has been proved to play an important role in the occurrence and development of aortic aneurysm mediated by vascular smooth muscle cell remodeling. OBJECTIVE:To review the epigenetic regulation mechanism underlying vascular smooth muscle cell remodeling during the occurrence and progression of aortic aneurysm. METHODS:Related articles published from 1970 to 2022 were retrieved from PubMed,Web of Science and CNKI databases.The keywords were"Aortic aneurysm,Vascular smooth muscle,Smooth muscle cells,Epigenetic,DNA methylation,Histone modification,Non coding RNA"in English and Chinese.Ultimately,we included 71 articles for review. RESULTS AND CONCLUSION:Epigenetic modification can influence the occurrence and progression of aortic aneurysm by targeting vascular smooth muscle cell remodeling and extracellular matrix degradation.Targeted epigenetic modification can play a key role in aortic aneurysm treatment,delaying the disease and improving the prognosis.Epigenetic related enzymes,such as DNA methylesterases and histone-modifying enzymes,can influence the progression of aortic aneurysm by regulating vascular smooth muscle cell remodeling,including cell proliferation,migration and apoptosis,and can be used as targets for drug therapy.The research of epigenetic modification on aortic aneurysm is still in the basic research stage and some epigenetic modification mechanisms have not yet been explored.With the development of medical research,targeted epigenetic modification is expected to achieve new breakthroughs in the treatment of aortic aneurysm and clinical transformation.

Objective: To investigate the association between tea consumption and lung cancer risk in Chinese males. Methods: Tea consumption and incident lung cancer cases were collected on a biennial basis among males in Kailuan Cohort during 2006-2015. Up to 31st December 2015, a total of 103 010 male candidates from the Chinese Kailuan Male Cohort Study were enrolled in the present study. Cox proportional hazards regression model was used to evaluate the association between tea consumption and risk of lung cancer in males. Results: The age of male candidates was (51.3±13.4)years old. There were 828 810.74 person-years of follow-up and 8.91 years of median follow-up period. During the follow-up, 964 lung cancer cases were identified. In male, the rate of never cosumers, tea drinkers (<4/week) and tea drinkers (≥4/week) were 58.17%(n=59 926), 24.04%(n=24 765) and 17.78%(n=18 319), respectively. After adjustment for potential confounding factors, HR (95%CI) of lung cancer for subjects with tea drinkers (<4/week) and tea drinkers (≥4/week) were 0.80 (0.63-1.02) and 1.02 (0.80-1.30), respectively, as compared with never cosumers. The results showed no significant association with lung cancer. Stratification analysis and sensitivity analysis showed no significant changes. Conclusion Our study has not found that tea consumption is significantly associated with the risk of male lung cancer.

Objective: To investigate the association between anthropometry and colorectal cancer risk in Chinese males. Methods: Anthropometry and incident colorectal cancer cases were collected on a biennial basis starting in May 2006 among males in Kailuan Cohort (2006-2014). In addition, electronic database of hospitals affiliated to Kailuan Community, Insurance System of Kailuan Community and Tangshan were also searched for supplementary information. Cox proportional hazards regression models and linear models were used to evaluate the association between baseline anthropometry and the risk of colorectal cancer in males. Results: A total of 106 786 males were included and 318 new colorectal cancer cases were identified in the Kailuan male cohort study, with 747 337.60 person-years follow-up by 31 December 2014. The median follow-up time was 7.90 years. Highest quartile waist circumference (≥94.0 cm) or WHtR (≥0.55) had 1.45 (95%CI: 1.05-2.02) and 1.66 (95%CI: 1.15-2.41) higher risk of colorectal cancer when compared with lowest waist circumference (<82.0 cm) or WHtR (<0.48) after adjusting for age, education, smoking, alcohol drinking, sitting time and dust exposure. Subgroup analyses by site indicated that males with BMI ≥26.27 kg/m², waist circumference ≥94.0 cm or WHtR ≥0.55 had HRs (95%CI) of 2.18(1.27-3.73), 2.20 (1.27-3.78) and 2.42 (1.29-4.56) for colon cancer risk, respectively. Linear models showed the HR of colon cancer and 95%CI would be 1.59 (1.24-2.02) with every 0.1 growth in WHtR. Conclusion Obesity may be responsible for an increased risk of colorectal cancer in male. Reasonable weight control may be one of the effective measures to prevent colorectal cancer.