Population structure of food-borne Staphylococcus aureus in China / 中华流行病学杂志

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.

Prediction of superantigen active sites and clonal expression of staphylococcal enterotoxin-like W / 中华流行病学杂志

Objective: The docking and superantigen activity sites of staphylococcal enterotoxin-like W (SElW) and T cell receptor (TCR) were predicted, and its SElW was cloned, expressed and purified. Methods: AlphaFold was used to predict the 3D structure of SElW protein monomers, and the protein models were evaluated with the help of the SAVES online server from ERRAT, Ramachandran plot, and Verify_3D. The ZDOCK server simulates the docking conformation of SElW and TCR, and the amino acid sequences of SElW and other serotype enterotoxins were aligned. The primers were designed to amplify selw, and the fragment was recombined into the pMD18-T vector and sequenced. Then recombinant plasmid pMD18-T was digested with BamHⅠand Hind Ⅲ. The target fragment was recombined into the expression plasmid pET-28a(+). After identification of the recombinant plasmid, the protein expression was induced by isopropyl-beta-D- thiogalactopyranoside. The SElW expressed in the supernatant was purified by affinity chromatography and quantified by the BCA method. Results: The predicted three-dimensional structure showed that the SElW protein was composed of two domains, the amino-terminal and the carboxy-terminal. The amino-terminal domain was composed of 3 α-helices and 6 β-sheets, and the carboxy-terminal domain included 2 α-helices and 7 antiparallel β-sheets composition. The overall quality factor score of the SElW protein model was 98.08, with 93.24% of the amino acids having a Verify_3D score ≥0.2 and no amino acids located in disallowed regions. The docking conformation with the highest score (1 521.328) was selected as the analysis object, and the 19 hydrogen bonds between the corresponding amino acid residues of SElW and TCR were analyzed by PyMOL. Combined with sequence alignment and the published data, this study predicted and found five important superantigen active sites, namely Y18, N19, W55, C88, and C98. The highly purified soluble recombinant protein SElW was obtained with cloning, expression, and protein purification. Conclusions: The study found five superantigen active sites in SElW protein that need special attention and successfully constructed and expressed the SElW protein, which laid the foundation for further exploration of the immune recognition mechanism of SElW.

Berberine alleviates programmed necrosis of metabolic-associated fatty liver disease via activating Nrf2 pathway in mice / 中华肝脏病杂志

Objective: To investigate the effect of berberine on programmed necrosis of hepatocytes induced by metabolic-associated fatty liver disease (MAFLD) in mice and its related molecular mechanism. Methods: Twenty male C57BL/6N mice were randomly divided into four groups (n=5 in each group): control group (S), fatty liver group (H), berberine group(B), nuclear factor erythroid 2-related factor 2 inhibitor group (Nrf2), and all-trans-retinoic acid (ATRA) group (A). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), triglycerides (TG), total cholesterol (TC), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) concentrations were detected at the end of week 12 to calculate fatty liver index (liver mass/body mass ratio). Liver tissue was stained with HE, Masson and Oil Red O, and SAF score was used to evaluate the degree of liver injury. The expression levels of hepatic programmed necrosis-related proteins, namely receptor-interacting protein kinase 3 (RIPK3), phosphorylated mixed series protease-like domain (p-MLKL) and Nrf2 were detected by Western blot method. One-way ANOVA was used for intragroup comparisons and LSD-t tests were used for intergroup comparisons. Results: Compared with S group, H group serum ALT, AST, LDH, TG, TC, TNF-α, IL-1β levels and fatty liver index were significantly increased. The liver tissue was filled with vacuolar-like changes and inflammatory cell infiltration. Numerous red lipid droplets were observed with oil red O staining. Collagen fiber hyperplasia was evident with Masson staining. SAF scores (6.60 ± 0.55 and 0.80 ± 0.45) were significantly increased. The expressions of RIPK3 and p-MLKL were up-regulated. Nrf2 level was relatively increased, and the differences were statistically significant (P < 0.05). Compared with H group, berberine intervention group liver biochemical indexes, lipid levels, pro-inflammatory mediator expression, fatty liver index, and SAF score were significantly reduced, and the expression of RIPK3 and p-MLKL were down-regulated, while Nrf2 levels were further increased, and the differences were statistically significant (P<0.05). Compared with B group, treatment with Nrf2 inhibitor had antagonized the protective effect of berberine on fatty liver. Serum ALT, AST, LDH, TG, TC and TNF-α, IL-1β levels, fatty liver index, and SAF scores were significantly increased and the expressions of RIPK3 and p-MLKL were relatively increased, and the differences were statistically significant (P < 0.05). Conclusion: Berberine can significantly improve the metabolic-associated fatty liver disease injury in mice, and its mechanism is related to activation of Nrf2 and inhibition of programmed necrosis of hepatocytes.

Investigation on the awareness of the residents around a nuclear power plant in Guangdong province / 中国职业医学

OBJECTIVE: To understand the general awareness of the residents around a newly built nuclear power,to evaluate the safety and the attitude on the construction of nuclear power. METHODS: By the stratified random sampling method,1 029 general publics and 260 representatives were selected for investigation. The participants were from 30 km range around the nuclear power plant,each 5 km was assigned as 1 layer and there were total 6 layers. RESULTS: 74. 9%( 965 /1 289) interviewees were not aware of nuclear power,3. 1%( 40 /1 289) interviewees were well or very-well understand nuclear power. The awareness score of the general publics was lower than that of the representatives( 1. 0 vs3. 0,P < 0. 01); male,younger people,higher educational level,higher family income,religious people and living close to the nuclear power plant had higher awareness( P < 0. 05). A total of 28. 4%( 366 /1 289) interviewees considered the nuclear power was very safe or safe. The evaluation of nuclear power safety of the general publics was inferior to the representatives( P < 0. 05). The representatives,older people and those living far away from the nuclear power have better evaluation on the nuclear power safety than the general publics( P < 0. 05). Only 13. 0%( 167 /1 289) interviewees supported building the nuclear power in their residence construction; male,people with family members working in nuclear power plant,people with high degree of awareness on nuclear power,considered highly safety of the nuclear power had higher support for the local nuclear power construction( P < 0. 05). The interviewees who mostly believe about nuclear energy sources were experts,government officials,plant management and domestic media. CONCLUSION: Residents around the nuclear power plant had low awareness of the knowledge about nuclear power. Therefore,it is necessary to enhance the awareness of residents on nuclear power and the trust on the government.

Logistic regression analysis on therapeutic effect of acupuncture on neck pain caused by cervical spondylosis and factors influencing therapeutic effect / 中国针灸

<p><b>OBJECTIVE</b>To explore the main factors influencing the therapeutic effect of acupuncture on neck pain caused by cervical spondylosis, so as to provide references for further increasing the therapeutic effect of acupuncture.</p><p><b>METHODS</b>One hundred and six cases were randomly divided into an observation group and a control group, 53 cases in each group. The observation group was treated with routine acupuncture at Dazhui (GV 14), Jingbailao (Ex-HN 15) and Jianzhongshu (SI 15); and the control group was treated with sham acupuncture at 1 cm lateral to Bailao (Ex-HN 15) and Jianzhongshu (SI 15). The needles were retained for 20 min in the two groups and infrared radiation was used for adjuvant treatment in this period. Northwick Park Neck Pain Questionnaire (NPQ) was used to assess the patients' quality of life before and after the treatment. The potential influential factors were analyzed by Logistic regression.</p><p><b>RESULTS</b>The effective rate was 75.5% in the observation group and 52.8% in the control group with a significant difference between the two groups (P<0.05). The Logistic regression analysis indicated that the therapeutic effect in the observation group was superior to the control group (OR = 2.670), and both the attack frequency and duration of the neck pain will influence the therapeutic effect (OR = 1.055 and OR = 2.446).</p><p><b>CONCLUSION</b>Acupuncture has a better therapeutic effect on neck pain caused by cervical spondylosis, and patient's clinical history about attack frequency and duration of neck pain are factors influencing clinical therapeutic effect.</p>

Multiple myeloma: past, present and future--editorial / 中国实验血液学杂志

Multiple myeloma is a neoplasm of mature and immature plasma cells, it remains an incurable disease using conventional chemotherapy and increasing aggressive approaches. In recent years, due to the better understanding of myeloma biology, genetics and tumor formation, there are lots of new active drugs or combinational chemotherapy regimens having been developed, such as proteasome inhibitors, immunomodulatory agents etc, they are more effective than conventional chemotherapy. This article summarizes the recent advances with the new options for the treatment of multiple myeloma.

Applied anatomy of upper fibular bone flap pedicled with circumflex fibular neck artery / 中华显微外科杂志

Objective To provide applied anatomy basis for upper fibular bone flap pedieled with cir- cumflex fibular neck artery.Methods The origin,course,branches,distribution and anastomosis of cir- cumflex fibular neck artery were observed on 54 sides of adult cadaver lower limb speeimens perfused with red latex.Results The circumflex fibular neck artery derived from popliteal artery (3.3?1.1)cm beneath the tip level of fibular head,with its length of (1.4?1.0) cm and diameter of (1.4?0.5) mm.The ascending periosteal branches of circumflex fibular neck artery anastomosed consistently with the descending periosteal branches of inferior lateral genicular artery.Conclusion The transplanting operative design of upper fibular bone flap pedicled with circumflex fibular neck artery was feasible.

Effects of formaldehyde inhalation on lung of rats / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To analyze protein changes in the lung of Wistar rats exposed to gaseous formaldehyde (FA) at 32-37 mg/m3 for 4 h/day for 15 days using proteomics technique.</p><p><b>METHODS</b>Lung samples were solubilized and separated by two-dimensional electrophoresis (2-DE), and gel patterns were scanned and analyzed for detection of differently expressed protein spots. These protein spots were identified by MALDI-TOF-MS and NCBInr protein database searching.</p><p><b>RESULTS</b>Four proteins were altered significantly in 32-37 mg/m3 FA group, with 3 proteins up-regulated, 1 protein down-regulated. The 4 proteins were identified as aldose reductase, LIM protein, glyceraldehyde-3-phosphate dehydrogenase, and chloride intracellular channel 3.</p><p><b>CONCLUSION</b>The four proteins are related to cell proliferation induced by FA and defense reaction of anti-oxidation. Proteomics is a powerful tool in research of environmental health, and has prospects in search for protein markers for disease diagnosis and monitoring.</p>

The expression and imprinting status of insulin-like growth factor 2 gene in colorectal cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the imprinting status and expression level of insulin-like growth factor 2 (IGF2) gene in colorectal cancer and to provide a clue for the mechanism of carcinogenesis of colorectal cancer.</p><p><b>METHODS</b>The expression levels of IGF2 in the paired colorectal cancer and adjacent normal tissue were examined and compared by use of semi-quantitative reverse transcription-polymerase chain reaction. The imprinting status of IGF2 was detected by restriction fragment length polymorphism. The relationships between the expression level of IGF2, its imprinting status, and the carcinogenesis of colorectal cancer were analyzed.</p><p><b>RESULTS</b>IGF2 was overexpressed in 82.4% (28/34) of colorectal cancer tissues which was significantly higher than those of the matched normal tissues (P<0.01, t=3.01). 87.5% (14/16) of colorectal cancer showed loss of imprinting(LOI), while 71.4%(10/14) of normal tissues also displayed LOI of IGF2.</p><p><b>CONCLUSION</b>Overexpression of IGF2 was found to play an important role in carcinogenesis of colorectal cancer. LOI of IGF2 may be a prophase manifestation of colorectal cancer.</p>