OBJECTIVETo investigate the effects of chronic aluminum exposure on the learning and memory abilities and brain-derived nerve growth factor (BDNF) in Sprague-Dawley (SD) rats.

METHODSThirty-two male SD rats were randomly and equally divided into 4 groups: control group and high-, middle-, and low-dose exposure groups. The rats in high-, middle-, and low-dose exposure groups were fed with the feed mixed with AlCl(3) (120.0, 12.0, and 1.2 mg/kg, respectively), while the rats in control group were fed conventionally. After 6 months of feeding, brain aluminum levels were determined by inductively coupled plasma mass spectrometry; Morris water maze was employed to test the learning and memory abilities; the expression and content of BDNF in brain tissue were measured by Western blot and enzyme-linked immuno sorbent assay (ELISA).

RESULTSThe high- and middle-dose exposure groups had significantly higher brain aluminum levels than the control group (P<0.05). The Morris water maze test showed that the high- and middle-dose exposure groups had significantly prolonged escape latency (P<0.05), significantly prolonged time taken to first reach the target quadrant (P<0.01), and significantly decreased number of platform crossings and time spent in the target quadrant (P<0.05), as compared with the control group. The Western blot and ELISA showed that the expression and content of BDNF in brain tissue decreased as the dose of AlCl(3) increased, and they were significantly lower in the high- and middle-dose exposure groups than in the control group (P<0.05).

CONCLUSIONChronic aluminum exposure (12.0 and 120.0 mg/kg) can lead to cognitive dysfunction in rats, and the decreased expression of BDNF may be one of the mechanisms of learning and memory deficits induced by aluminum.

Aluminum ; toxicity ; Animals ; Brain ; metabolism ; Brain-Derived Neurotrophic Factor ; metabolism ; Male ; Maze Learning ; drug effects ; Rats ; Rats, Sprague-Dawley ; Toxicity Tests, Chronic

A 44-residue hybrid peptide (CB (1-24)-Arg-Ser-Tyr-Tan (4-21)) incorporating 1-24 residues of cecropin B (CB) and 4-21 residues of thanatin (Tan) was designed and constructed. The CB-Tan gene was cloned into expression plasmid pGEX-3X and expressed in E. coli BL21. The fusion protein was purified by affinity chromatography. After digested with enterokinase the gene product released with antibacterial activity and gave one band in Tricine-SDS-PAGE.
Amino Acid Sequence ; Anti-Bacterial Agents ; metabolism ; Antimicrobial Cationic Peptides ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; Insect Proteins ; biosynthesis ; Molecular Sequence Data ; Peptides, Cyclic ; biosynthesis ; Recombinant Fusion Proteins ; biosynthesis ; isolation & purification ; pharmacology

OBJECTIVETo investigate the antibacterial effect of a particular antimicrobial peptide Cecropin B(CB) on Pseudomonas aeruginosa infection of wound in mice.

METHODSThirty ICR mice were enrolled in the study, and the Pseudomonas aeruginosa infection model was reproduced by excision of the full layer of dorsal skin with an area of 1 cm x 1 cm. Then they were randomly divided into C ( control, n = 10, with wet compress of isotonic saline at 3 postinjury hour( PIH) ) , M (with hydropathic compress of 100 g/L mafenide at 3 PIH), A (with wet compress of 1 000 mg/L Cecropin B at 3 PIH) groups. The changes in body temperature and hemogram in each group were determined before and 4 days after injury. Quantitative examination were used to detect the quantity of bacteria in muscular tissue of the wounds, and the survival of the mice were observed on 4 post-injury day( PID).

RESULTSThe wounds were moist with more exudation in C group,while that in other groups were dry without obvious exudation. The body temperature of the majority of the mice in each group were elevated, but the number of leucocytes in each group was lowered after operation. The quantity of bacteria in muscle in A group[ (42 +/- 50) CFU/g] was obviously lower than that in M group [(886+/-804) CFU/g, P <0.05] , and it was all obviously lower than that in C group[ (41 +/-28) x 10(5) CFU/g, P <0.01]. The number of surviving mice after 4 PID in C group was evidently smaller than that in A and M groups( P <0. 05).

CONCLUSIONThe cecropin B possesses obvious anti-bacterial effect on the Pseudomonas Aeruginosa infected wounds of ICR mice, and it can reduce the mortality.

Animals ; Antimicrobial Cationic Peptides ; therapeutic use ; Disease Models, Animal ; Insect Proteins ; therapeutic use ; Male ; Mice ; Mice, Inbred ICR ; Pseudomonas Infections ; drug therapy ; Wound Infection ; drug therapy ; microbiology

The tracheal aspirates and serum samples of a suspected human case of high-pathogenic avian influenza (firstly found in Shenzhen, China) were collected and tested by a series of assays. The results showed that the RNA extracted from the tracheal aspirate specimens of the patient was confirmed positive for H5N1 avian influenza virus by Real-time PCR. The H5N1 avian influenza virus was isolated from patient's tracheal aspirates on MDCK cell and was named A/Guangdong/2/06(H5N1). The viral load of tracheal aspirates collected at different time points were detected by Real-time PCR. The virus microneutralization and the antigenic ratio of human H5N1 isolated were also assayed. It was found that when the virus load decreased gradually after the disease onset, the serum neutralizing antibody titer in the patient increased to 1 : 160 and subsequently decreased gradually. By molecular analysis, the eight gene segments of A/Guangdong/2/06 revealed to be similar to that of H5N1 avian influenza viruses isolated from south China in 2005-2006. However, there were obvious differences in the gene sequence of the detected H5N1 viral RNA as compared with that of the strains isolated from Vietnam, Thailand and Indonesia.
Adult ; Amino Acid Sequence ; Antibodies, Viral ; blood ; Humans ; Influenza A Virus, H5N1 Subtype ; genetics ; immunology ; isolation & purification ; Influenza, Human ; diagnosis ; virology ; Male ; Molecular Sequence Data ; Mutation ; Neutralization Tests ; RNA, Viral ; blood

OBJECTIVE: To study the effects and mechanisms of curcumin alleviating oxidative stress induced by overtraining and inhibiting renal apoptosis in rats. METHODS: Male Wistar rats of 7 weeks old were divided into control group (C group, 12), overtraining group (OM group, 11), curcumin + overtraining group (COM group, 14). Group C did not undergo any exercise intervention. Rats in OM group and COM group underwent 8-week incremental load swimming training. During the training, the COM group was treated with curcumin at the dose of 200 mg/(kg·d) in the volume as 5 ml/kg by intragastric administration, and the other groups was treated with an equal volume of 0.5% carboxymethylcellulose. Twenty-four hours after the last training, renal histopathological changes were observed by light microscopy, related biochemical indicators in blood and renal tissue were detected. RESULTS: The results showed that after 8 weeks of incremental load swimming training, the renal tissue structure of group C was normal under light microscope; histopathological changes were observed in OM group; COM group was significantly relieved compared with OM group. Compared with group C, serum levels of corticosterone (Cor), creatinine (Cr) and blood urea nitrogen (BUN) in OM group were increased (<0.01), serum level of testosterone (T) was lower (<0.01); the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) was not changed significantly (>0.05), while the expression of heme oxygenase-1 (HO-1) was decreased (<0.05), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity were decreased (<0.01), malondialdehyde (MDA) concentration was increased (<0.01); the renal apoptosis was increased (<0.01), the expression of anti-apoptotic B cell lymphoma-2 protein (Bcl-2) was decreased (<0.01), and the expression of proapoptotic Bcl-2 associated X protein (Bax) was increased (<0.01). Compared with the OM group, Cor level was decreased (<0.01) in the COM group, T level was increased (<0.01), Cr and BUN levels were lower (<0.05); the expression of Nrf2 and HO-1 were increased (<0.05), T-AOC and SOD activity were increased (<0.01), MDA concentration was decreased (<0.05); the renal apoptosis was decreased (<0.05), the expression of Bcl-2 was increased (<0.05), and the expression of Bax was decreased (<0.01). The trend of testosterone/corticosterone ratio between groups was consistent with testosterone change, and the change trend of Bcl-2/Bax ratio was consistent with the change of Bcl-2. CONCLUSIONS The 8-week incremental load swimming training triggered excessive training in rats, aggravated oxidative stress and accelerated renal apoptosis, leading to pathological changes and dysfunction of kidney. Curcumin can up-regulate expression of Nrf2 and HO-1, effectively alleviates oxidative stress induced by overtraining, thereby increasing Bcl-2 expression, decreasing Bax expression, inhibiting renal apoptosis and protecting renal tissue structure and function properly.
Animals ; Apoptosis ; Curcumin ; Kidney ; Male ; Oxidative Stress ; Rats ; Rats, Wistar

Objective: To investigate the mid-and long-term clinical effects of tricuspid valvuloplasty with the implantation of an artificial plastic ring. Methods: Data of 677 patients who had functional tricuspid regurgitation and left cardiac valve disease and underwent tricuspid valvuloplasty and left cardiac valve surgery were retrospectively. Among these patients, 353 underwent simple suture annuloplasty (group A) while the rest 324 patients underwent artificial plastic ring annuloplasty (group B). The two-year and more-than-two-year clinical and ultrasonocardiograph (UCG) follow-up data of the two groups were obtained and compared. Results: A total of 600 patients (88.6%) completed the long-term follow-up (more than two years). The two-year follow-up showed no significant difference in the incidence of mild tricuspid regurgitation between the two groups (82.2% vs. 92.7%, P=0.37). However, there were significantly more cases that developed into moderate to severe tricuspid regurgitation in group A than in group B (17.8% vs. 7.3%, P=0.031). The long-term follow-up revealed that the recurrence rate of tricuspid regurgitation in group B was significantly lower than that in group A (11.0% vs. 25.0%, P=0.029), and the ratio of cases developing into moderate to severe tricuspid regurgitation in group A was significantly higher than that in group B (28.9% vs. 9.9%, P=0.007). The comparison between the two intra-group time segments showed that the development of tricuspid regurgitation in group A was significantly increased (28.9% vs. 17.8%, P=0.022), but in group B it was relatively stable (9.9% vs. 7.3%, P=0.52). Conclusions: Artificial ring annuloplasty is associated with significantly less tricuspid regurgitation than simple suture annuloplasty.

Work-related musculoskeletal disorders (WMSDs) refer to musculoskeletal disorders caused by work or work as the main cause, which are characterized by high prevalence and heavy burden of disease as a global problem. The classification and catalog of occupational diseases is of great significance for guiding the prevention and control of occupational diseases and safeguarding the rights and interests of workers. The types of WMSDs included in the list of occupational diseases vary greatly from country to country, and the regulations on specific pathogenic factors are also inconsistent. By sorting out and analyzing the lists and characteristics of WMSDs at home and abroad, and using the International Statistical Classification of Diseases and Related Health Problems (ICD-10) in occupational health to standardize of WMSDs in various countries, which would lay the foundation for future multi-country WMSDs occupational health registration and disease burden research, and provide a reference for China to revise the WMSDs list.
Humans ; Musculoskeletal Diseases/prevention & control* ; Occupational Diseases/prevention & control* ; Prevalence ; Risk Factors ; Surveys and Questionnaires

OBJECTIVE: To study the effects of aerobic exercise combined with chlorella pyrenoidos of disintegrated cell wall on the lipid metabolism in rats with high-fat diet. METHODS: Fifty-five male Wistar rats were subjected to adaptive feeding for 4 days and weight-free swimming training for 3 days, 20 min/d. After eliminating 5 rats that were not suitable for swimming training, the other rats were randomly divided into 5 groups according to their body weight:control group (C group), high fat diet group (H group), high-fat diet + chlorella group(HC group), high fat diet + aerobic exercise group (HM group), high fat diet + chlorella + aerobic exercise group (HMC group), 10 in each group. The HM and HMC group were subjected to 60 min/d swimming training for 6 weeks with non-weight-bearing. Group C were fed regular diet. The other groups were fed with high-fat diet, the rats in group HC and HMC were intragastrically treated with chlorella pyrenoidos of disintegrated cell wall at the dose of 3.9 g/(kg·d), the volume was 5 ml/kg, and the other groups are given equivalent saline. The Lee's index and biochemical indexes of blood and liver were measured after 6 weeks. RESULTS: Compared with group C, Lee's index, serum levels of free fatty acids(FFA), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-c), liver FFA and interleukin-10 (IL-10) were increased significantly (<0.01), the serum level of high-density lipoprotein cholesterol (HDL-c) was decreased significantly (<0.01) in group H. Compared with group H, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05 or <0.01), serum level of HDL-c was increased significantly (<0.05 or <0.01) in group HC, HM and HMC. Compared with group HC and HM, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05), serum level of HDL-c was increased significantly (<0.05) in group HMC. CONCLUSIONS Aerobic exercise and chlorella pyrenoidos of disintegrated cell wall can improve lipid metabolism in rats with high-fat diet and reduce the lipid toxicity caused by obesity. Joint intervention is more effective than single intervention.
Animals ; Cell Wall ; Chlorella ; Diet, High-Fat ; Lipid Metabolism ; Male ; Physical Conditioning, Animal ; Rats ; Rats, Wistar

Objective To investigate the clinical features of unexpected sudden death (SUD) clustered in families in Yunnan province.Methods This retrospective study analyzed the clinical features of SUD occurred between July to September 2005 in 7 families in Yunnan province.Results All 16 SUD patients shared common clinical features such as fatigue and repeated syncope and one group of SUD patients (n = 8 from 4 families) presented with the gastric intestinal tract manifestations including nausea, vomiting, abdominal pain and diarrhea with suspected dietary history and abnormal laboratory enzyme findings (GOT/ GPT,CK/CKMB,LDH/LDH1 etc.).In SUD patients without gastric intestinal tract manifestations (n = 8 from 3 families), there were no clear symptoms before death and repeated ventricular tachycardia and ventricular fibrillation were recorded in one survivor.There was no clear evidence for the involvements of hereditary and infectious factors for observed SUD.conclusion The reason for the unexpected sudden death clustered in 7 families in Yunnan remains unclear.Repeated syncope and fatigue served as the common clinical features in the presence or absence of gastric intestinal tract manifestations in all SUD cases.Further studies are needed to clarify the pathology and detailed clinical manifestations of SUD occurred in this area.

Objective:The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China.Methods:This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems.Results:According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%).Conclusion:Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.