Acute Disease ; Adult ; Benzene ; poisoning ; Humans ; Male ; Multiple Organ Failure ; chemically induced ; Occupational Diseases ; complications

OBJECTIVETo investigate the bond strengths of customized titanium bracket manufactured by selective laser melting.

METHODSEighty human premolars which had been extracted for orthodontic purpose were collected and divided randomly (by random table) into two groups (customized bracket group and 3M bracket group, 40 molars in each group). The 35% phosphoric acid was used for etching and the brackets were bonded with 3M Unitek bonding adhesive. All bonded specimens were placed in saline for 24 hours at room temperature and were tested on DWD3050 electronic testing machine to determine the shear bond strength and tensile bond strength. After debonding, the adhesive remnant indexes (ARI) were recorded.

RESULTSThe shear bond strengths of customized brackets was 6.80 (6.20, 8.32) MPa, which was significantly lower than that of the 3M brackets [10.46 (9.72, 11.48) MPa] (Z = -3.463, P < 0.05). And the tensile bond strengths of customized brackets was (6.93 ± 1.21) MPa, which was significantly higher than that of the 3M brackets [(5.88 ± 1.23) MPa] (t = 2.81, P < 0.05). No significant difference was found in the ARI between two different kinds of the brackets.

CONCLUSIONSThe shear bond strength and tensile bond strength of both kinds of brackets were enough for clinic application.

Acid Etching, Dental ; Adolescent ; Bicuspid ; Child ; Composite Resins ; chemistry ; Dental Bonding ; methods ; Dental Debonding ; Dentin-Bonding Agents ; chemistry ; Humans ; Lasers ; Orthodontic Brackets ; Phosphoric Acids ; chemistry ; Random Allocation ; Shear Strength ; Tensile Strength ; Titanium

OBJECTIVETo analyze the difference between the frequencies of HLA-A-B, B-DRB1 and A-B-DRB1 haplotype, as well as their linkage disequilibrium pattern in patients with acute lymphoblastic leukemia(ALL) and healthy controls from Northern Chinese Han.

METHODSThe frequencies of HLA-A-B, B-DRB1, A-B-DR haplotypes and linkage disequilibrium were estimated by Expectation Maximization method based on the genotypes of 643 patients with ALL and 2 0359 unrelated healthy donors, and the statistical significance between the two groups were estimated by chi-square test. Linkage disequilibrium was analyzed with population genetic methods.

RESULTSThe most common HLA-A-B, B-DRB1, and A-B-DR haplotypes were A30-B13, A2-B46, A33-B58, B13-DR7, B46-DR9, B52-DR15, B58-DR17, A30-B13-DR7, A33-B58-DR17 and A1-B37-DR10 in both groups. The frequencies of A30-B13, A2-B46, A33-B44, B13-DR7, A30-B13-DR7 and A2-B46-DR9 haplotypes and linkage disequilibrium value were significantly decreased (P<0.05) in the patient group than that in the control group. On the other hand, the frequencies of A2-B52, A31-B61, A24- B8, B60-DR9, B27-DR4, B52-DR14, B44-DR17, B27-DR12 and A11-B27-DR12 haplotypes and linkage disequilibrium value were significantly increased (P<0.05) in the patient group than that in the control group.

CONCLUSIONThere are some common and positive linkage disequilibrium haplotypes in both the ALL patients and the healthy donors in Northern Chinese Han. Interestingly, some haplotypes and their linkage disequilibrium patterns had significantly different distributions between the two groups. The study provided basic data for the relationship of ALL and HLA haplotype and for finding the HLA-A, B, DR matching donors.

Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; China ; Ethnic Groups ; genetics ; Female ; HLA Antigens ; genetics ; Haplotypes ; Humans ; Linkage Disequilibrium ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Young Adult

OBJECTIVETo construct recombinant lentiviral vectors carrying Rheb gene and its mutant Rheb'D60K gene, and examine their expression in human liver cancer cells.

METHODSRheb gene was amplified by PCR to construct the recombinant plasmid LV31-Rheb-WT and LV31-Rheb-D60K. HEK-293 FT cells were contransfected with the recombinant lentiviral vector together with a lentiviral package plasmid to produce the lentiviral particles. The expression of PS6 protein was detected in the lentivirus-infected MCF-7 cells. The apoptosis of SK-HEP-1 cells transfected with LV31-Rheb-WT or LV31-Rheb-D60K was observed.

RESULTSThe recombinant LV31-Rheb-WT and LV31-Rheb-D60K vectors were confirmed by PCR and DNA sequencing. Western blotting showed that PS6 protein expression was increased in LV31-Rheb-WT-transfected cells while decreased in LV31-Rheb-D60K-transfected cells. LV31-Rheb-D60K-transfected SK-HEP-1 cells showed more obvious apoptosis after starvation than LV31-Rheb-WT-transfected cells.

CONCLUSIONLentiviral vectors carrying Rheb gene and its mutant has been successfully constructed, which can be useful in further investigation of the role of Rheb gene in cancer cells.

Apoptosis ; genetics ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Genetic Vectors ; genetics ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; metabolism ; Liver Neoplasms ; metabolism ; pathology ; MCF-7 Cells ; Monomeric GTP-Binding Proteins ; biosynthesis ; genetics ; Mutant Proteins ; genetics ; Neuropeptides ; biosynthesis ; genetics ; Ras Homolog Enriched in Brain Protein ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection

Objective:To obtain recombinant D227A mutation Staphylococcal enterotoxin A protein(rSEAD227A) with low toxicity but still retain its immunological activity and high purity. Methods: The SEA gene containing D227A mutation was cloned by PCR. By constructing pET44a-SEAD227Avector and transfecting the expression strain Rosetta, inclusion bodies were solubilized with guanidium hydrochloride and refolded by gradient dialysis;proteins were purified using StrepⅡ affinity chromatography,and identified by Western blot and high performance liquid chromatography-mass spectrometry(LC-MS/MS). Results: The D227A mutation of SEA was cloned and the expression system of Rosetta-rSEAD227Awas constructed. The purified rSEAD227Aprotein was obtained by refolding with gradient dialysis and affinity purification. LC-MS/MS analysis confirmed that the tryptic digested rSEAD227A peptide sequences matched the sequences of SEA in the database. Conclusion: The rSEAD227A protein in high purity was obtained,which provided the ex-perimental basis for further basic research and clinical application of SEA.

Objective　To compare the irradiation-protective and inter-synergestic effects of E838,WR-2721, Rubia cordifolia, cystamin e hydrochloride and ethinyl estradiol on radiation and combined radiation-burn injury. Methods　Above-mentioned drugs were given to the mice i ntraperitoneally, or intragastrcally, then, the mortality and the average surviv al d for 30 d were observed before and after the administration of the drug s. Results　①When drugs were before injury , the survival rate and the average survival d of the radiation and combined radiation-burn injured mice were increased obviously with the best effect in E838 and WR-2721. ②When drugs were given after injury, E838 and R. cordifolia also kept the effect. ③Combined appling WR-2721（pre) and E838（post）displayed a significant syner gistic reaction. Conclusion　E838 and WR-2721 are more e ffective than the others in the prevention of radiation.

OBJECTIVETo explore the establishment of the mimetic aging effect in guinea pigs induced by D-galactose, and to detect the biological indicatrix associated with hearing loss and provide a new tool for molecular pathogenesis of hearing loss.

METHODSTotal of 51 guinea pigs were randomly divided into three groups: group A (model aging group, n = 25), which were injected with D-galactose (200 mgxkg(-1)xd(-1)) by intra peritoneum for 6 weeks, group B (model control group, n = 18), which were given the same amount of saline only, and group C (vacant group, n = 15) were not treated. Then, The guinea pigs in group A and B were exposed in noise for 8 days, 8 hours once a day. Auditory brainstem response (ABR) was used to test the hearing threshold of guinea pigs thrice, first before the drug administered, then after 6 weeks the drug used, third after noise exposure. And colorimetry was used to analyze the activity of superoxide dismutase (SOD) and malon dialdehyde (MDA) in brain and liver tissue. The DNA of inner ear tissue was harvested and amplified fragment length polymorphism (AFLP) was used to detect the differential polymorphic markers.

RESULTSAfter injection, there was no significant difference in elevation of ABR threshold between the group A and group B (t = 1.14, P > 0.05). However, exposure of noise later, elevation in ABR threshold of (22.97 +/- 10.56) dB peSPL was observed in group A, and (14.16 +/- 7.36) dB peSPL in group B. The was significant difference in variation of hearing threshold between group A and group B (t = 2.78, P < 0.05). The activity of SOD in brain and liver tissue in group A was lower than that in group B. the level of MDA was opposite between group A and group B. The difference between group A and group B was significant (P < 0.01). A differential polymorphic marker was observed by AFLP.

CONCLUSIONSThe mimetic aging effect of the guinea pigs can be induced by D-galactose, and this model can not directly induce the hearing loss. The differential polymorphic marker possibly act as a predisposing factor which can greatly enhance the sensitivity of the ear to the noise.

Aging ; Amplified Fragment Length Polymorphism Analysis ; Animals ; Auditory Threshold ; Disease Models, Animal ; Evoked Potentials, Auditory, Brain Stem ; Female ; Galactose ; pharmacology ; Guinea Pigs ; Male ; Presbycusis ; chemically induced ; physiopathology

Aim To investigate the therapeutic effect of the MW-9 on ulcerative colitis(UC)and reveal the underlying mechanism, so as to provide a scientific guidance for the MW-9 treatment of UC. Methods The model of lipopolysaccharide(LPS)-stimulated RAW264.7 macrophage cells was established. The effect of MW-9 on RAW264.7 cells viability was detected by MTT assay. The levels of nitric oxide(NO)in RAW264.7 macrophages were measured by Griess assay. Cell supernatants and serum levels of inflammatory cytokines containing IL-6, TNF-α and IL-1β were determined by ELISA kits. Dextran sulfate sodium(DSS)-induced UC model in mice was established and body weight of mice in each group was measured. The histopathological damage degree of colonic tissue was assessed by HE staining. The protein expression of p-p38, p-ERK1/2 and p-JNK was detected by Western blot. Results MW-9 intervention significantly inhibited NO release in RAW264.7 macrophages with IC50 of 20.47 mg·L-1 and decreased the overproduction of inflammatory factors IL-6, IL-1β and TNF-α(P<0.05). MW-9 had no cytotoxicity at the concentrations below 6 mg·L-1. After MW-9 treatment, mouse body weight was gradually reduced, and the serum IL-6, IL-1β and TNF-α levels were significantly down-regulated. Compared with the model group, MW-9 significantly decreased the expression of p-p38 and p-ERK1/2 protein. Conclusions MW-9 has significant anti-inflammatory activities both in vitro and in vivo, and its underlying mechanism for the treatment of UC may be associated with the inhibition of MAPK signaling pathway.

OBJECTIVES: To analyze the causes of perinatal death and related factors from the perspective of forensic medicine, and to provide references for reducing perinatal mortality and guidance for forensic identification. METHODS: A retrospective analysis was performed on 102 cases of perinatal autopsy with clinical data from the Department of Forensic Medicine of Chongqing Medical University in 2004-2016. RESULTS: Of the 102 cases of perinatal deaths, 66 （64.71%） were neonatal deaths, 24 （23.53%） were stillborn foetuses, and 12 （11.76%） were stillbirths. Among the 66 neonatal death cases, 39 （59.09%） died within 1 d, 19 （28.79%） died within 1-3 d, and 8 （12.12%） died within >3-7 d of birth. The top 3 causes of neonatal death were pulmonary diseases, congenital malformation, umbilical cord and placental abnormalities. The causes of stillborn foetus and stillbirth were mainly umbilical cord and placental abnormalities, and intrauterine asphyxia. CONCLUSIONS Pulmonary diseases, umbilical cord and placental abnormalities, and congenital malformations are the main causes of perinatal death. In order to reduce the perinatal mortality, pre-pregnancy examination and prenatal care should be strengthened, and the knowledge of pregnancy care should be popularized.
Autopsy ; Cause of Death ; Female ; Humans ; Infant ; Infant Mortality ; Pregnancy ; Retrospective Studies ; Stillbirth

OBJECTIVE: To observe the effects of moxibustion at "Mingmen" (GV 4) and "Guanyuan" (CV 4) on immune function and intestinal flora in healthy rats, thereby investigating the underlying mechanism of moxibustion on immune function. METHODS: Twenty 8-week-old SD rats were randomly divided into a young blank group and a young moxibustion group, with 10 rats in each group. Similarly, twenty 8-month-old SD rats were randomly divided into a middle-aged blank group and a middle-aged moxibustion group, with 10 rats in each group. The rats in the two moxibustion groups received moxibustion at "Mingmen" (GV 4) and "Guanyuan" (CV 4), 15 min per session, once daily, five times a week, for a total of four months. The rats in the two blank groups were fed under normal conditions. After the intervention, thymus and spleen indexes were calculated; the morphology of thymus and spleen tissues was observed using HE staining; the flow cytometry was used to detect the expression of CD and CD T lymphocytes and the CD/CD ratio was calculated; ELISA was used to measure the serum levels of tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin-6 (IL-6), interleukin-10 (IL-10), and interleukin-17 (IL-17); 16S rRNA high-throughput sequencing was used to analyze the intestinal flora. Additionally, the correlation between the relative abundance of intestinal flora and serum levels of TNF-α, IFN-γ, IL-6, IL-10 and IL-17 was analyzed. RESULTS: Compared with the young blank group, the young moxibustion group exhibited an increase in the cortical area of thymus tissue with tighter lymphocyte arrangement; compared with the middle-aged blank group, the middle-aged moxibustion group showed an increase in thymus index (P<0.05) and an increase in the cortical area of thymus tissue. There were no significant differences in spleen index between the 2 moxibustion groups and the 2 blank groups (P>0.05). There were no significant differences in the expression of CD, CD, and CD/CD ratio between the 2 moxibustion groups and the corresponding blank groups (P>0.05). Compared with the young blank group, the young moxibustion group had elevated IL-6 level (P<0.05); compared with the middle-aged blank group, the middle-aged moxibustion group had decreased IL-10 and IL-17 levels (P<0.05). Compared with the young blank group, the young moxibustion group exhibited increased Sobs index, Ace index, and Chao index (P<0.01, P<0.05), as well as increased relative abundance of Spirochaetota, Treponema, Turicibacter, Rikenellaceae_RC9_gut_group (P<0.05), and decreased relative abundance of Dubosiella (P<0.05). Compared with the middle-aged blank group, the middle-aged moxibustion group had increased relative abundance of Spirochaetota, Treponema, norank_f_Peptococcaceae (P<0.05), and decreased relative abundance of Proteobacteria, Allobaculum, and Faecalibaculum (P<0.05). Correlation analysis revealed that relative abundance of Eubacterium_xylanophilum_group and unclassified _f_Lachnospiraceae was negatively correlated with serum TNF-α level (r=-0.39, P=0.03; r=-0.24, P=0.04), while relative abundance of norank_f_norank_o_Clostridia_UCG-014 and Lactobacillus was positively correlated with serum TNF-α level (r=0.37, P=0.04; r=0.43, P=0.02). The relative abundance of Roseburia and Monoglobus was negatively correlated with serum IFN-γ level (r=-0.40, P=0.02; r=-0.44, P=0.01), while relative abundance of Lactobacillus was positively correlated with serum IL-10 level (r=0.43, P=0.02). CONCLUSION Moxibustion could improve immune function in healthy rats, and its mechanism may be related to the regulation of relative abundance of intestinal flora.
Rats ; Animals ; Moxibustion ; Rats, Sprague-Dawley ; Interleukin-10/genetics* ; Interleukin-17 ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/genetics* ; Gastrointestinal Microbiome ; RNA, Ribosomal, 16S ; Interferon-gamma ; Immunity