BACKGROUND: Cancellous bone, as an important part of bone, is a kind of porous, inhomogeneous, anisotropic and viscoelastic structure, which plays a critical role in load transmission and energy absorption. Therefore,research on its mechanical properties is of great significance.OBJECTIVE: To investigate the compressive properties of cancellous bone at different stress rates and its creep behaviors at different stress levels.METHODS: The fresh cancellous bone from pig femur was used as the material, and subjected to different stress until the compressive strain of sample was up to 5%. The constant compressive stress levels were loaded on the surface of cancellous bone for 7200 s to observe its creep behaviors.RESULTS AND CONCLUSION: (1) In the uniaxial compression test, the stress values and Young's modulus increased with the stress rate increasing under the same strain value. (2) The stress-strain curves of cancellous bone were different at different loading rates, indicating that the mechanical properties of cancellous bone depend on the loading rate. (3) In the creep test, the creep strain increased with the increase of stress level, but the creep compliance decreased with the increase of stress level. (4) These results suggest that the stress rate and stress level have significant influence on compressive properties of cancellous bone, which provide reference for avoiding cancellous bone injury.

OBJECTIVETo establish a highly sensitive and specific assay to detect dengue virus (DENV) envelope protein domain III (EDIII) IgG antibody, and to explore its value in the diagnosis and seroepidemiological survey of dengue.

METHODSThe DENV EDIII IgG antibody capture ELISA was developed using the recombinant full-length DENV EDIII, which was prepared by Pichia yeast expression system as the capture antigen. The serum samples were collected from the same group of 35 DENV-1 patients of primary infection during disease period in 2006 and their follow-up phase in 2010; and the sensitivity of the assay was compared to that of the commercial Panbio DENV IgG ELISA.

RESULTSThe sensitivity of DENV EDIII IgG ELISA in detecting the serum samples from disease period and follow-up phase was 87% (20/23) and 94% (33/35), respectively; whereas the sensitivity of Panbio DENV IgG ELISA was 71% (25/35) and 0, respectively. The sensitivity of DENV EDIII IgG ELISA in detecting the serum samples from both periods was similar, without statistical significance (χ(2) = 0.946, P = 0.331). For serum samples from disease period, the sensitivity of DENV EDIII IgG ELISA was comparable with that of Panbio DENV IgG ELISA (χ(2) = 1.924, P = 0.165). However, DENV EDIII IgG ELISA demonstrated a significantly higher sensitivity than Panbio DENV IgG ELISA in detecting the serum samples from follow-up phase (χ(2) = 62.432, P = 0.000).

CONCLUSIONDENV EDIII IgG capture ELISA is highly sensitive in detecting IgG in the serum samples from either disease period or follow-up phase. This method might be a promising alternative for diagnosis and seroepidemiologic survey of dengue.

Antibodies, Viral ; blood ; Dengue ; diagnosis ; immunology ; virology ; Dengue Virus ; immunology ; Enzyme-Linked Immunosorbent Assay ; methods ; Humans ; Immunoglobulin G ; blood ; Protein Structure, Tertiary ; Sensitivity and Specificity ; Seroepidemiologic Studies ; Viral Envelope Proteins ; immunology

OBJECTIVEThis study is to verify the use of rich BHI medium to substitute synthetic media for gene regulation studies in Yersinia pestis.

METHODSThe transcriptional regulation of rovA by PhoP or via temperature upshift, and that of pla by CRP were investigated when Y. pestis was cultured in BHI. After cultivation under 26 °C, and with temperature shifting from 26 to 37 °C, the wild-type (WT) strain or its phoP or crp null mutant (ΔphoP or Δcrp, respectively) was subject to RNA isolation, and then the promoter activity of rovA or pla in the above strains was detected by the primer extension assay. The rovA promoter-proximal region was cloned into the pRW50 containing a promoterless lacZ gene. The recombinant LacZ reporter plasmid was transformed into WT and ΔphoP to measure the promoter activity of rovA in these two strains with the β-Galactosidase enzyme assay system.

RESULTSWhen Y. pestis was cultured in BHI, the transcription of rovA was inhibited by PhoP and upon temperature upshift while that of pla was stimulated by CRP.

CONCLUSIONThe rich BHI medium without the need for modification to be introduced into the relevant stimulating conditions (which are essential to triggering relevant gene regulatory cascades), can be used in lieu of synthetic TMH media to cultivate Y. pestis for gene regulation studies.

Bacterial Proteins ; genetics ; metabolism ; Bacteriological Techniques ; Culture Media ; pharmacology ; Gene Expression Regulation, Bacterial ; drug effects ; physiology ; Yersinia pestis ; metabolism ; physiology

OBJECTIVETo investigate the association between a new polymorphism (IVS3-20 T>C GenBank accession number: AY463003) in intro 3 of the parkin gene and the risk for Parkinson's disease (PD) in Chinese, particularly the relation between this polymorphism and the age of onset of PD patients.

METHODSPD was diagnosed according to the criteria of Core Assessment Program for Intracerebral Transplantations(CAPIT). All patients and controls were examined by two neurologists and were of the Han ethnic background. Polymerase chain reaction (PCR), denaturing high performance liquid chromatography (DHPLC) and sequencing were used to determine the genotype of each subject.

RESULTSA total of 312 PD patients (including 99 early-onset PD patients and 213 late-onset PD patients) and 236 controls were studied. The C/C homozygote was not found in this study. Chi-square analysis revealed that the frequencies of the C allele and T/C genotype were higher in total PD group but were not statistically different from those of the control group (P=0.6350 and 0.6331, respectively). After being stratified by age of onset, the frequency of T/C genotype was significantly higher (OR=3.52, 95%CI 0.97-13.13) in PD group with an onset age at or below 45 years old (7.07%), compared with that in the control group (2.12%). Similarly, C allele was much higher (OR=3.42, 95%CI 0.96-12.57, P=0.0276) in the early-onset PD group (3.90%) than that in the control group (1.06%). The linear trend analysis showed that both the T/C genotype and C allele increased significantly in the PD group with the increase of the onset age [chi-square(trend of Genotypes)=4.414, P=0.036; chi-square(trend of Alleles)=4.344, P=0.037]. On the other hand, there was no difference in the frequencies of allele and genotype between the late-onset PD patients and controls.

CONCLUSIONThe above results suggest that the parkin IVS3-20 T>C polymorphism might be a genetic risk factor for early-onset PD in Chinese.

Adult ; Age Distribution ; Aged ; Aged, 80 and over ; Base Sequence ; Female ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Parkinson Disease ; genetics ; Polymorphism, Genetic ; Sex Distribution ; Ubiquitin-Protein Ligases ; genetics

Coronary Angiography ; Coronary Vessel Anomalies ; diagnostic imaging ; therapy ; Embolization, Therapeutic ; methods ; Fistula ; congenital ; diagnostic imaging ; therapy ; Heart Ventricles ; abnormalities ; diagnostic imaging ; Humans ; Male ; Middle Aged

OBJECTIVETo study the distribution of Yersinia enterocolitica and its virulence factors in Nantong, Jiangsu.

METHODSYersinia strains were isolated from livestock and poultry. Conventional PCR was used to detect the virulence factors of all strains and strain 0:8 was analyzed by pulsed-field gel electrophoresis(PFGE).

RESULTSThe combined isolation rate of Yersinia enterocolitica from livestock and poultry was 31.06% and the gene distribution characters were: 39.57% of them were ail-, ystA- , ystB-, yadA- , virF-; 60.43% were ail- , ystA- , ystB + , yadA- , virF- respectively. The two reference strains from America and Denmark showed similar electrophoresis patterns but were significantly different with O:8 strains isolated from China while the serotypes of Yersinia enterocolitica O:3 and O:9 which were the main epidemic strains in China, were not found in this area.

CONCLUSIONThe pathogenic Yersinia enterocolitis O:3 and O:9 were not found in Nantong,Jiangsu province.

Animals ; Animals, Domestic ; microbiology ; China ; Electrophoresis ; Poultry ; microbiology ; Virulence Factors ; genetics ; metabolism ; Yersinia enterocolitica ; genetics ; isolation & purification ; pathogenicity

OBJECTIVE: To investigate the correlation between serum interleukin-33 (IL-33), β₂microglobulin (β₂-MG) levels and Durie-Salmon (DS) stage in patients with multiple myeloma (MM). METHODS: 100 MM patients admitted to the First Affiliated Hospital of Fujian Medical University from March 2019 to January 2021 were selected and divided into stage I, stage II and stage III groups according to the DS staging system. A baseline data questionnaire of patients was designed, then the relevant baseline data and laboratory test results of patients were recorded. The levels of serum IL-33 and β₂-MG of all patients were detected, and the correlation between serum IL-33, β₂-MG levels and DS stage of MM patients was analyzed. RESULTS: Among the 100 patients with MM, there were 32 cases in stage I, 39 cases in stage II and 29 cases in stage III. The levels of serum CRP and β₂-MG of patients in stage III were significantly higher than those of patients in stage I and II, and the levels of serum CRP and β₂-MG of patients in stage II were significantly higher than those of patients in stage I, the differences were statistically significant (P <0.05). The level of serum IL-33 of patients in stage III was significantly lower than that of patients in stage I and II, and the level of serum IL-33 of patients in stage II was significantly lower than that of patients in stage I, the differences were statistically significant (P <0.05). There was no statistical significant difference in other data between groups (P >0.05). Kendall's tau-b correlation analysis showed that the levels of serum CRP and β₂-MG were positively correlated with DS stage in MM patients (r =0.534, 0.776), the level of serum IL-33 was negatively correlated with DS stage in MM patients (r =-0.759). Ordered logistic regression analysis and forest plot showed that the low level of serum IL-33 and the high level of β₂-MG were the influencing factors of high DS stage in MM patients (P <0.05 ). CONCLUSION DS stage of MM patients is closely related to the levels of serum IL-33 and β₂-MG, that is, the lower the serum IL-33 level and the higher the β₂-MG level, and the higher the DS stage of MM patients.
Humans ; Interleukin-33 ; Multiple Myeloma ; Prognosis ; HLA-G Antigens/blood*

Dental caries are the most prevalent chronic infections in the oral cavity,and Streptococcus mutans acts as the main cariogenic bacterial species. Antibacterial quaternary ammonium compounds (QAs) have been developed to preveFnt or treat dental caries. However, there is no report on the tolerance of S.mutans to QAs.In this study, we investigated the development of S. mutans persistence induced by a novel dental caries defensive agent, dimethylaminododecyl methacrylate (DMADDM), for the first time. Typical biphasic killing kinetics for persisters were observed in both S. mutans planktonic and biofilm cultures challenged by DMADDM at concentrations of 20 and 200 μg·mL-1,respectively. The persisters tolerated six other antibiotics with different antibacterial mechanisms, while only daptomycin and vancomycin could slightly reduce the persister numbers in planktonic cultures. The distribution of persisters in DMADDM-treated biofilms was similar to that in the untreated control, except that the total biomass and biofilm height were significantly reduced.A higher exopolysaccharides (EPS):bacteria ratio was observed in DMADDM-treated biofilms. Persisters in biofilms significantly upregulated gtf gene expression, indicating an increase in the bacteria's ability to produce EPS and an elevated capability of cariogenic virulence. Carbon source metabolism was significantly reduced,as related metabolic genes were all downregulated in persisters. Concentrations of 0.1 mM, 1 mM and 10 mM of extra glucose significantly reduced the number of persisters both in planktonic and biofilm conditions. The formation of non-inheritable and multidrug tolerant persisters induced by DMADDM suggested that drug tolerance and new persistent eradication strategies should be considered for oral antibacterial agents.

OBJECTIVETo investigate the effects of autophagy activator (rapamycin, RAPA) and autophagy inhibitor (hydroxychloroquine, HCQ and 3-methyl adenine, 3-MA) on the proliferation, apoptosis and autophagy of multiple myeloma cell line of RPMI8226.

METHODSRPMI8226 cells were treated with autophagy regulating drugs of different concentrations. The proliferation and apoptosis of cells were determined by CCK-8 and flow cytometry, respectively. The expressions of apoptosis-related proteins BCL-2, caspase-3 and PARP protein were assessed by Western blot. Autophagy was detected by monodansylcadaverine staining. Autophagic protein (LC-3b) and apoptosis-related proteins (caspase-3, PARP and BCL-2) were analyzed by Western blot.

RESULTSRAPA and HCQ inhibited the proliferation of RPMI8226 in a concentration- and time-dependent manner, and increased the apoptosis. However, 3-MA did not show significantly inhibitory effect on the proliferation and apoptosis of RPMI8226. MDC staining showed that the more autophagic vacuoles could be detected in the higher concentration of RAPA, but the less autophagic vacuoles in the higher concentration of HCQ and 3-MA. Western blot showed that RAPA increased the expression of LC3-II/LC3-I, caspase-3 and PARP, but inhibited the expression of BCL-2. HCQ inhibited the expression of LC3-II/LC3-I and BCL-2, but increased the expression of caspase-3 and PARP. 3-MA inhibited the expression of LC3-II/LC3-I, but had no effect on the expression of caspase-3, PARP or BCL-2.

CONCLUSIONRapamycin can inhibit the proliferation, induce apoptosis and autophagy of RPMI 8226, the hydroxychloroquine can inhibit autophagy and proliferation of RPMI 8226, and induce apoptosis, the 3-MA can inhibit autophagy of RPMI 8226, but hardly has any effects on proliferation and apoptosis of RPMI 8226 cells.

Apoptosis ; Autophagy ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Multiple Myeloma

Under the background of the Belt and Road Initiative, the exchange of traditional medicine has become inevitable. China and Thailand are amicable neighbors, and the cooperation between the two countries in the field of traditional medicine has become increasingly close in recent years. Nevertheless, on account of the differences in culture, region, politics, economy and so on, the two countries have common features and unique characteristics in the theoretical system of traditional medicine, quality standard control of medicinal materials, research and development and use of medicinal materials. This paper summarizes the similarities and differences as well as the development opportunities of traditional medicine between China and Thailand. The specific content involves the development history, resources, and use of medicinal resources in Thailand, the main achievements and existing problems of modern research of Thai medicine, the spread and development of Chinese medicine in Thailand, and the spread and development of Thai medicine in China. Furthermore, the paper outlines the recent situation of traditional medicine interflow and cooperation between the two countries, and predicts the prospects for cooperation and development of traditional medicine between China and Thailand in the context of the Belt and Road Initiative, especially in the joint research and development and the improvement of quality standards of important medicinal plant varieties commonly used by the two countries and circulated across the border. Through the exchange and mutual learning, we can step up the traditional medicine cooperation between China and Thailand, which will provide advantageous conditions for the safety of medicine use as well as political and social stability between the two countries.
China ; Medicine, Chinese Traditional ; Medicine, Traditional ; Plants, Medicinal ; Research ; Thailand