Evaluation of safety and immunogenicity of hepatitis E vaccine in maintenance hemodialysis patients / 中华预防医学杂志

Objective: To evaluate the safety and immunogenicity of hepatitis E vaccine(HEV)in Maintenance hemodialysis(MHD)patients. Methods: Based on an open-labeled controlled trial, from May 2016 to March 2018, 35 eligible MHD patients were recruited in the Hemodialysis Center of Zhongshan Hospital Affiliated to Xiamen University as the experimental group, and 70 MHD patients with matched age, gender and underlying diseases as the control group. The experimental group received HEV at 0, 1 and 6 months according to the standard vaccination procedures, while the control group received routine diagnosis and treatment without vaccine and placebo injection to observe the safety and immunogenicity of the vaccine. The safety of vaccine in MHD population was evaluated by the incidence of adverse reactions/events in the experimental and control groups. The immunogenicity of HEV in MHD patients was evaluated by comparing the data from the phase Ⅲ clinical trial. Results: The overall incidence of adverse reactions/events was 17.1% (18/105), and there were no grade 3-4 adverse reactions/events related to vaccination. In the experimental group, the incidence of local adverse reactions/events was 20.0% (7/35), and the incidence of systemic adverse reactions/events was 17.1% (6/35).There was no significant difference in the incidence of systemic adverse reactions/events between the experimental group and the control group (P>0.05). There were 23 patients receiving 3 doses with the standard schedule. The positive rate of HEV-IgG antibody was 100% and the GMC was 14.47(95%CI:13.14-15.80) WU/ml, which showed no significant difference compared with the 46 patients in Phase Ⅲ clinical trial (t=-1.04, P>0.05). Conclusion: Recombinant HEV has good safety and immunogenicity in MHD patients.

Application of typical case combined with practice teaching in pediatric clinical teaching / 中华医学教育探索杂志

Objective:To explore the application of typical case combined with practice teaching in the pediatric clinical teaching.Methods:A total of 80 clinical interns majoring in pediatrics who practiced in the Affiliated Hospital of Jining Medical University between September 2019 and January 2020 were selected as the research subjects, and they were randomly divided into observation group ( n=41) and control group ( n=39). The control group adopted conventional teaching while the observation group were given typical case combined with practice teaching model. After 16 weeks of training, the theoretical knowledge, practical operation [direct observation of procedural skill (DOPS) evaluation, and mini-clinical evaluation exercise (Mini-CEX)] and overall performance were analyzed in the two groups of students. SPSS 19.0 was used for t test, chi-square test and rank sum test. Results:After the internship, the theoretical scores of common pediatric diseases, clinical disease characteristics, etiopathogenesis, treatment regimen and complications were enhanced in the two groups, and the above scores in observation group were higher than those in control group ( P<0.05). Besides, the DOPS scores and Mini-CEX scores of the two groups were increased, and the scores were higher in observation group than in control group ( P<0.05). Furthermore, the overall excellent rate of the observation group was 87.80% (36/41), which was higher than 69.23% in control group (27/39). Survey found that the number of interns who believed that the teaching regimen could deepen the knowledge mastery degree, increase the internship interest and improve the comprehensive ability, internship efficiency and clinical thinking ability was more in observation group than in control group. Conclusion:Typical case combined with practice teaching can effectively deepen the interns' understanding of theoretical knowledge of clinical pediatrics, improve the practical operation ability and arouse the interest in learning.

Toxicokinetics of Vitexin Injection in Beagle Dogs / 中国药学杂志

OBJECTIVEP: To investigate the toxicokinetic and tissue distribution of vitexin in Beagle dogs. METHODS: Beagle dogs were randomly divided into three groups, and received vitexin injection at small, medium and big doses of 50, 20 and 8 mg•kg-1. They were given medicine once a day for consecutive 3 months by intravenous drip. The blood samples of Beagle dogs were drawn at different time points on the first and last day of administration, and concentrations in plasma were detected by HPLC method. RESULTS: Intravenous drip the vitexin injection at the doses of 8, 20 and 50 mg•kg-1, the blood concentration of vitexin linearly metabolized in Beagle dogs when given medicine for 1, 22, 44 and 83 d. Vitexin was significantly accumulated in Beagle dogs, and the accumulation was disappeared, and the exposure decreased with the prolonged time at the dose of 50 mg•kg-1; at the dose of 8 and 20 mg•kg-1, vitexin did not accumulate in Beagle dogs, and the exposure decreased with prolonged administration time. CONCLUSION: There is no accumulation of repeated drug delivery in the Beagle dog's body by intravenous drip at the doses of 8 and 20 mg•kg-1.

PGL3 is required for chlorophyll synthesis and impacts leaf senescence in rice / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Rice leaf color mutants play a great role in research about the formation and development of chloroplasts and the genetic mechanism of the chlorophyll (Chl) metabolism pathway. pgl3 is a rice leaf color mutant derived from Xiushui11 (Oryza sativa L. spp. japonica), treated with ethyl methane sulfonate (EMS). The mutant exhibited a pale-green leaf (pgl) phenotype throughout the whole development as well as reduced grain quality. Map-based cloning of PGL3 revealed that it encodes the chloroplast signal recognition particle 43 kDa protein (cpSRP43). PGL3 affected the Chl synthesis by regulating the expression levels of the Chl synthesis-associated genes. Considerable reactive oxygen species were accumulated in the leaves of pgl3, and the transcription levels of its scavenging genes were down-regulated, indicating that pgl3 can accelerate senescence. In addition, high temperatures could inhibit the plant's growth and facilitate the process of senescence in pgl3.

Preparation of icariin-poly(lactic acid)/hydroxyapatite composite bone-graft substitutes by supercritical carbon dioxide method / 中国组织工程研究

BACKGROUND: Our previous findings have shown that poly(lactic acid)/hydroxyapatite (PLA/HA) composite biomaterials prepared by the supercritical carbon dioxide method have good physiochemical properties and biocompatibility. However, the composite materials only have osteoconductivity but no osteoinductivity. OBJECTIVE: To prepare icariin-PLA/HA (IC-PLA/HA) composite biomaterials with good osteoconduction and osteoinduction. METHODS: The supercritical carbon dioxide method was used to prepare IC-PLA/HA composite biomaterials containing 10-4, 10-5, 10-6mmol/g IC, named as IC-PLA/HA(1 000), IC-PLA/HA(100) and IC-PLA/HA(10). PLA/HA composite material served as controls. Biomechanical properties, porosity, sustained release characteristics were detected, and scanning electron microscope observation was performed, in order to screen out the optimal IC content in the composite materials. RESULTS AND CONCLUSION: (1) Compressive strength and elastic modulus of IC-PLA/HA(1 000), IC-PLA/HA(100) and IC-PLA/HA(10) showed no difference from those of PLA/HA. (2) The porosity of all the composite materials was over 75%, and there was still no difference among groups. (3) The IC release from IC-PLA/HA was faster within the first 3 days, and then reduced gradually. However, after 7 days, the IC release plateaued, and the IC release amount from the IC-PLA/HA(100) was close to 10-7mol/L that had been confirmed to be an effective and safe concentration in the previous experiments. (4) Under the scanning electron microscope, HA and PLA were mixed homogeneously and IC was difficult to be identified. The pore size of the IC-PLA/HA(100) ranged from 50 μm to 150 μm. Overall, the IC-PLA/HA composite biomaterials have good mechanical and sustained-release properties.

Association of platelet count, fibrosis-4, and aspartate aminotransferase-to-platelet ratio index with the development and severity of esophageal varices in patients with liver cirrhosis / 临床肝胆病杂志

Objective To investigate the clinical value of platelet count (PLT), fibrosis-4 (FIB-4), and aspartate aminotransferase-to-platelet ratio index (APRI) in predicting the development and classification of esophageal varices (EVs) . Methods A retrospective analysis was performed for the clinical data of 163 patients with liver cirrhosis who visited Department of Hepatology in The First Hospital of Jilin University from January 2012 to December 2015. All patients underwent upper gastrointestinal endoscopy within one week after admission. According to PLT, the patients were divided into PLT ≤50 × 109/L group with 27 patients, PLT 50 × 109/L-≤100 × 109/L group with 84 patients, PLT 100 × 109/L-≤150 × 109/L group with 26 patients, and PLT＞ 150 × 109/L group with 26 patients. The Child-Pugh score, FIB-4, and APRI were recorded, and the association of PLT, FIB-4, and APRI with EVs was analyzed. A one-way analysis of variance was used for comparison of normally distributed continuous data between multiple groups, and the LSD-t test was used for further comparison between any two groups; the Kruskall-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups, and the Dunn-Bonferroni test was used for further comparison between any two groups. The chi-square test was used for comparison of categorical data between groups, and the Fisher's test was used for the data which did not meet the conditions of the chi-square test. Spearman rank correlation was used to investigate the correlation of PLT, FIB-4, and APRI with EVs. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were used to evaluate the values of PLT, FIB-4, and APRI in the diagnosis of EVs. Results Of all 163 patients with liver cirrhosis, 114 developed EVs and 49 did not experience EVs. There was a significant difference in the incidence rate of EVs between the cirrhotic patients with different PLTs (χ2= 27. 36, P ＜ 0. 001) . Compared with those with PLT≤150 × 109/L, the cirrhotic patients with PLT＞ 150 × 109/L had a significantly lower proportion of patients with EVs (34. 6％ vs 76. 6％, P ＜ 0. 001) or severe EVs (3. 8％ vs 46. 7％, P ＜ 0. 001) . There were significant differences in FIB-4 and APRI between the patients with different PLTs (χ2= 102. 58 and 57. 02, both P ＜ 0. 001) . PLT was negatively correlated with the degree of EVs (r =-0. 491, P ＜ 0. 001), and FIB-4 and APRI were positively correlated with the degree of EVs (r = 0. 460 and 0. 325, both P ＜0. 001) . PLT had an AUC of 0. 739 and an accuracy of 75. 4％ in predicting the presence or absence of EVs, while FIB-4 had an AUC of 0. 732 and an accuracy of 71. 2％ and APRI had an AUC of 0. 651 and an accuracy of 72. 4％ . PLT had an AUC of 0. 763 and an accuracy of 69. 3％ in predicting the presence or absence of severe EVs, while FIB-4 had an AUC of 0. 742 and an accuracy of 67. 5％ and APRI had an AUC of 0. 676 and an accuracy of 66. 3％ . Conclusion Cirrhotic patients with PLT＞ 150 × 109/L have a significant reduction in the risk of EVs or severe EVs. PLT, FIB-4, and APRI are correlated with the degree of EVs in cirrhotic patients, but they cannot fully replace gastroscopy.

Mechanical properties of human enamel based on resonant ultrasound spectroscopy / 医用生物力学

Objective To investigate the mechanical properties of human enamel based on resonant ultrasound spectroscopy (RUS). Methods The rectangular parallelepiped specimens of human enamel were processed. The theoretical resonant frequencies of specimens were estimated and paired with the experimental resonant frequencies measured from RUS experiments. An iterative procedure was used to adjust elastic constants of enamel until the theoretical frequencies corresponded to the experimental frequencies based on minimum mean-squared error criterion. In addition, elastic modulus, shear modulus and Poisson’s ratio were calculated respectively. Results The elastic modulus, shear modulus and Poisson’s ratio ranged from 61.52 to 80.46 GPa, 21.51 to 51.86 GPa and 0.18 to 0.43, respectively. Eliminating the effect of large specimen variances, the average of elastic modulus, shear modulus and Poisson’s ratio was 72.84 GPa, 31.94 GPa and 0.27, respectively. Conclusions RUS performs a feasibility of measuring the mechanical properties of human enamel with repeatable and nondestructive advantages. All the elastic constants and mechanical parameters can be estimated through a signal experiment. The results provide references for the development of biomimetic dental restoration materials.

Mechanical properties of human enamel based on resonant ultrasound spectroscopy / 医用生物力学

Objective To investigate the mechanical properties of human enamel based on resonant ultrasound spectroscopy (RUS).Methods The rectangular parallelepiped specimens of human enamel were processed.The theoretical resonant frequencies of specimens were estimated and paired with the experimental resonant fre quencies measured from RUS experiments.An iterative procedure was used to adjust elastic constants of enamel until the theoretical frequencies corresponded to the experimental frequencies based on minimum mean-squared error criterion.In addition,elastic modulus,shear modulus and Poisson's ratio were calculated respectively.Results The elastic modulus,shear modulus and Poisson's ratio ranged from 61.52 to 80.46 GPa,21.51 to 51.86 GPa and 0.18 to 0.43,respectively.Eliminating the effect of large specimen variances,the average of elastic modulus,shear modulus and Poisson's ratio was 72.84 GPa,31.94 GPa and 0.27,respectively.Conclu sions RUS performs a feasibility of measuring the mechanical properties of human enamel with repeatable and nondestructive advantages.All the elastic constants and mechanical parameters can be estimated through a sig nal experiment.The results provide references for the development of biomimetic dental restoration materials.

Diagnostic Significance of BAT in Anaphylaxis to Non-ionic Contrast Media / 法医学杂志

OBJECTIVE@#To investigate the diagnostic significance of basophil activation test (BAT) in anaphylaxis to non-ionic contrast media through testing the content of CD63, mast cell-carboxypeptidase A3 (MC-CPA3), and terminal complement complex SC5b-9 of the individuals by testing their levels in the normal immune group and the anaphylaxis groups to β-lactam drugs and non -ionic contrast media.@*METHODS@#The CD63 expression of basophilic granulocyte in blood was detected by flow cytometry. The levels of MC-CPA3 in blood serum and SC5b-9 in blood plasma were detected by ELISA.@*RESULTS@#The CD63 expression of basophilic granulocyte in blood, the levels of MC-CPA3 and SC5b-9 of anaphylaxis to non-ionic contrast media and β-lactam drugs were significantly higher than that in normal immune group (P < 0.05).@*CONCLUSION@#There is activation of basophilic granulocytes, mast cells and complement system in anaphylaxis to non-ionic contrast media. BAT can be used to diagnose the anaphylaxis to non-ionic contrast media.

Construction of Hospital Informatization Service Platform in the New Media Age / 医学信息学杂志

The paper summarizes application of new media in patient informatization services in hospitals, introduces exploration and practices made by Children′s Hospital of Shanghai on new media informatization platform construction from such aspects of OA system-basedwindowservice platform,order typeservice model provided to the public onMicroblogandWeChatplatforms andex-press typemobile network terminal service for hospital staffs.The service effects are summarized at last.

Establishment and application of human CHO/NTR1 system / 药学学报

Neurotensin receptor-1 (NTR1), which can stimulate the intracellular cascade signal pathway, belongs to the large superfamily of G-protein coupled receptors. NTR1 is related to the occurrence and development of several kinds of diseases. In order to screen the inhibitors for the cancers associated with NTR1 protein, we established a CHO (Chinese hamster ovary) cell line in which human neurotensin receptor-1 was highly expressed. The method is to construct the recombinant plasmid which was lysed with the hNTR1 gene and transfect it into CHO cells. After selected with G418, the cell line was evaluated by Western blotting analysis and calcium flux assays. Through the calcium flux assays on FlexStation 3, we got the EC50 value of neurotensin peptide which is the natural NTR1 agonist, and the IC 50 value of SR48692 which is the known NTR1 antagonist. The established human CHO/NTR1 cell line can be used to study the profile of NTR1 biological activity and further screen of NTR1 antagonists and agonists.

Application of photosynthetic bacteria biotransformation in research of Chinese materia medica / 中草药

Microbial transformation technology has been applied in the study of Chinese materia medica (CMM) widely. Photosynthetic bacteria biotransformation in the research of Chinese medicine pharmaceutics has become one of the focuses in the field of microbial transformation technology. In this paper, we summarized the pharmacological activity and pharmacodynamic material bases of CMM metabolized by photosynthetic bacteria, in addition, summarized the mechanism of photosynthetic bacteria biotransformation. We also pointed out the problems needed to be studied in the future.

Summarization of the pathogen and therapy of secondary glaucoma after vitrectomy / 国际眼科杂志(Guoji Yanke Zazhi)

Secondary glaucoma is a kind of complications after vitrectomy, its etiologies are various and complex. Ineffective therapies might cause irreversible damage on optic nerves and visual field defect, even the loss in visual function. Nowadays, this project has been paid great attention by various researches both in China and abroad. Both the pathogens and therapies of secondary glaucoma after vitrectomy are analyzed as follows.

Triphasic mechanical properties of osteoarthritis cartilage with different pathological grades / 医用生物力学

Objective To obtain the axial elastic modulus of rabbit articular cartilage based on the ultrasound swelling observation technique and the triphasic theory, and to explore the triphasic mechanical properties of the osteoarthritis cartilage with different pathological grades. Methods The articular cartilage samples from rabbit knees were assessed according to the different pathological grades. The swelling strains were recorded based on the high frequency transient ultrasound measurement technique. The axial elastic modulus of the cartilage samples was extracted based on the fixed charge density, the water volume fraction and the triphasic model. Correlation analysis was also made. Results There were both significant differences in axial elastic modulus between the normal cartilages and among the osteoarthritis cartilage with different pathological grades (P<0.05). The value of axial elastic modulus decreased with the increase of osteoarthritis grades. For normal cartilage samples, the average axial elastic modulus was (15.87±6.30) MPa. For osteoarthritis cartilages of grade 1, 2 and 3, the value of axial elastic modulus were (11.33±5.21), (9.15±5.68) and (6.05±4.99) MPa, respectively. Conclusions This study showed there are significant differences in triphasic mechanical properties of the articular cartilage with different osteoarthritis grades, which may provide some new thought for the quantitative assessment of osteoarthritis grade based on mechanical properties of cartilage.

The prognostic significance of Omi/HtrA2 expression, and correlation between Omi/HtrA2 and hypoxia-inducible factor-1α in primary hepatocellular carcinoma cells / 中华外科杂志

<p><b>OBJECTIVES</b>To investigate the prognostic significance of Omi/HtrA2 expression, and the correlation between Omi/HtrA2 and Hypoxia-inducible factor (HIF)-1α in primary hepatocellular carcinoma cells.</p><p><b>METHODS</b>The expression of HIF-1α and Omi/HtrA2 in 43 cases of hepatic carcinoma tissues were detected immunohistochemically. Follow-up data were obtained to perform the Kaplan-Meier survival analysis. The change of Omi/HtrA2 expression in HepG2 cell was measured after HIF-1α expression of HepG2 in vitro was regulated by Tet-on expression system.</p><p><b>RESULTS</b>Omi/HtrA2 expression was correlated with lymph node metastasis and recurring within liver during 2 years. Statistical analysis estimation showed the cumulative survival rate of post-hepatectomy for the patients with the positive expression of Omi/HtrA2 was higher than that for other patients with the negative expression of Omi/HtrA2 (χ(2) = 6.13, P = 0.013). In the common paraffin-embedded specimen of hepatocellular carcinoma, most of the samples showing negative or weak positive HIF-1α immunopositivity showed moderate positive or strong positive Omi/HtrA2 immunopositivity, while most of the samples showing moderate positive or strong positive HIF-1α immunopositivity showed negative or weak positive Omi/HtrA2 immunopositivity. The mRNA expression intensity of Omi/HtrA2 was decreasing with the HIF-1α expression increasing, and the difference was statistically significant(F = 106.766, P < 0.01).</p><p><b>CONCLUSIONS</b>Omi/HtrA2 may be an important prognostic marker for primary hepatocellular carcinoma. Omi/HtrA2 expression is reversely correlated with HIF-1α expression in hepatocellular carcinoma. During the apoptotic process Omi/HtrA2 participating in hepatocellular carcinoma cells, HIF-1α is involved in the controlling and regulating of Omi/HtrA2 expression.</p>

Influence of erythropoietin on expression of matrix metalloproteinases in retinal pigment epithelium with photic injury / 中华实验眼科杂志

Background Increase in ophthalmic optical medical instruments and microsurgical applications leads to retinal photochemical damage and other problems delivery of a variety of devices,so the in-depth study and understanding of its pathogenesis after retina light damage can provide a reference for the clinical treatment of related diseases.Objective This study was to investigate the therapeutic effect and relative mechanism of erythropoietin (EPO) on mouse retina photic injury by studying the expression of matrix metalloproteinases-2 (MMP-2)and MMP-9.Methods Fifty-two SPF BALB/c mice were randomized into normal control group,simple light-induced group and EPO pretreatment group by balloting method.The mice of simple light-induced group and EPO pretreatment group were continuously irradiated with 6000 lx diffuse light for 4 hours in a home-made box to establish the models of light-induced damage;while recombinant human EPO (rhEPO)of 5000 U/kg was intraperitoneally injected prior to the light exposure in the EPO pretreatment group.The expressions of MMP-2 and MMP-9 were examined at 6,12,36,72,96 hours and 7 days following light-exposure by immunohistochemistry.Results Edema and structural disorder of RPE cells appeared inthe simple light-induced group after light-exposure and aggravated with lapse of light-exposure time,but no similar change was seen until 7 days in the EPO pretreatment group.The immunohistochemistry findings showed that the expression of MMP-2(A value)in RPE cells was less in the normal mice.However,a large quantity of positive cells appeared in RPE layer 36 hours after light-exposure.Compared with the simple light-induced group,the positive expression of MMP-2 protein in EPO pretreatment group was significantly decreased,showing statistically significant differences among these three groups and different time points (Fgroup =3.68,P =0 04; Ftime =9.13,P=0.00).There was hardly any MMP-9 expression in the retina of the normal mice.In simple light-induced group,a few of positive cells appeared in RPE layer 6 hours after light-exposure and reached its peak 12 hours following light-exposure.The gradually down-regulation of MMP-9 expression happened 96 hours later following light-irradiation.The expression tendency of MMP-9 in EPO pretreatment group was similar to the simple light-induced group.Significant differences in expressions of MMP-9 were found among different groups and time points (Fgroup=3.61,P =0.04;Ftime =16.91,P=0.00).Conclusions MMP-2 and MMP-9 may be involved in the mechanism of retina photic injury by down-regulating the expression of MMP-2 and MMP-9 in RPE cells.

Mechanism of the aging phenomenon with passage of human retinal pigment epithelial cell / 中华实验眼科杂志

BackgroundRetinal pigment epithelial (RPE)cell senescence damage the metabolism of photoreceptor,leading to retinal dysfunction and loss of vision.To understand RPE cell senescence mechanism will contribute to the study of age-related macular degeneration ( AMD).ObjectiveThe present study was to prepare the ageing RPE cell model with passage and explore its potential mechanisms.MethodsThis study was approved by the Ethic Committee of Qingdao University Medical College,and the informed consent was obtained from each gravida.Six human eyeballs were obtained from artificial labor fetusl with the gestational age 16-28 weeks.RPE cells were isolated,cultured and passaged in vitro to establish the cell replicative aging model.The third to twelfth cells were collected to be used to this experiment.Human keratin was used to identify the cells by immunochemistry,and MTT method was utilized to assess the proliferation and viability of different generations of cells as the A490 value.The cellular cycles and transmembrane potential (△ψm)of mitochondrion (△ψm) with passage were detected and compared using Flow Cytometry. Results Cultured and passaged cells showed the hexagon in shape with the melanin in 1-2 generations of cells and presented with the brown staining in cytoplasm for human keratin.The melanin was absent in the third generation cells.Vibrant growth statues were seen from the 3-6 generations cells and thereafter the proliferation ability reduced.The cells of G0/G1 phase were gradually elevated with the passage from 3 - 12 generations with a percentage of 68.40％ in the third generation of cells to 87.33％ in the twelfth generation of cells,showing a significant difference among various generations ( F =180.43,P =0.00),and that of the sixth,ninth and twelfth generation of cells was significant higher than the third,sixth and ninth generation respectively (t =4.002,P＜0.05 ; t=12.885,P＜0.01 ;t=16.387,P＜0.01 ).MTT assay showed that of RPE cells were significantly declined with the passage ( F =38.77,P =0.00),and the A490 value of the ninth,twelfth generations of cells was considerably lower in comparison with sixth and ninth generation respectively ( t =5.991,11.983,P＜0.01 ).From 3 through 12 generations of cells,the staining intensity of rhodamine 123 was gradually decreased ( F =121.68,P =0.00 ),and the staining intensity in the sixth,ninth and twelfth generation of cells was significant lower than that the third,sixth and ninth generation respectively(t=6.918,7.620,11.207,P＜0.01 ).Conclusions A replicative aging model can be successfully created by the passage in vitro using human fetal RPE cells.The reduce of transmembrane potential and damage of mitochondria might be one of mechanisms of senescence of RPE cells.

Analyzing the mutations of rpoB gene in Mycobacterium tuberculosis clinical isolates by probe melting analysis assay / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical performance of a probe melting analysis (PMA)-based real-time PCR detection kit in rapid detection of rifampin-resistant mutations in Mycobacterium tuberculosis (MTB).</p><p><b>METHODS</b>The specificity of the assay was evaluated by detecting 37 non-tuberculous mycobacteria (NTM), and the detection limit of the method was evaluated by genomic DNA of a standard strain H37Rv. Finally, 962 clinical isolates were analyzed with the PMA assay by detecting mutations in rifampin resistance-determining region (RRDR) of rpoB gene, and results were verified with DNA sequencing.</p><p><b>RESULTS</b>Among 37 NTM strains, three strains showed drug resistant mutation signals. The PMA method could detect down to 30 bacteria per reaction. Sample analysis showed that 186 of 962 isolates were mutants, 751 isolates were wild type and 25 isolates failed to give amplification signals. Among the mutant samples detected, 112 samples from November 2009 to April 2010 were further analyzed by sequencing, as well as 200 wild-type samples. The results showed a complete agreement with the PMA assay except for 5 samples failed in sequence analysis.</p><p><b>CONCLUSION</b>The PMA assay is rapid, accurate and easy-to-use, and thus can be used for detection of rifampin-resistant in clinical isolate samples.</p>

Correlation study on bone density, microstructure and acoustic parameters of cancellous bone at different stages of decalcification / 医用生物力学

Objective To study changes and correlations in ultrasound acoustic parameters, bone density and microstructure of the cancellous bone at different stages of decalcification. Methods Fifteen defatted porcine cancellous bone specimens were decalcified at different decalcification stages, and the bone density, microstructure and acoustic parameters were measured by Micro CT and ultrasound system, respectively, before and after the decalcification. Correlations between acoustic parameters, bone density and microstructure were investigated. Results With the loss of calcium in bone specimens, BMD (bone mass density), BS/TV and BV/TV decreased continuously. Microstructure parameters SMI and BS/BV increased, while Tb.Th and Tb.N decreased with Tb. Sp increasing. Degree of anisotropy (DA) increased. Acoustic parameter SOS increased at first, and then decreased, with nBUA slightly decreasing. High correlation was found between acoustic parameters, BMD and bone microstructure parameters. Conclusions Ultrasound acoustic parameters are correlated with BMD and bone microstructure. This study may provide some reference information for the early diagnosis of osteoporosis based on ultrasound.

The etiological identification of an aseptic encephalitis outbreak (ten cases) in a hospital of Xiamen city, 2011 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To identify the etiology of an aseptic encephalitis outbreak (ten cases) in a hospital of Xiamen city from 11 to 17 May, 2011.</p><p><b>METHODS</b>A total of ten patients' throat swabs, anal swabs and cerebrospinal fluid were collected and detected by RT-PCR for pan-enterovirus. The samples containing detectable pan-enterovirus were tested by PCR with genotype-specific general primers located in VP1 region of enterovirus genotype A, B and C (HEV-A, B and C). The PCR products of VP1 segment were purified and sequenced, and phylogenetic analysis was performed. Meanwhile, the pathogens in those samples were isolated in Vero cell culture. Homologous analysis of VP1 sequences were carried out for the cultured virus samples and the original clinical samples to identify the outbreak etiology.</p><p><b>RESULTS</b>Among the ten cases, seven cases were positive for pan-enterovirus nucleic acid. When tested by genotype-specific PCR, the throat and anal swab samples from those 7 patients were positive with HEV-B VP1 primers. Meanwhile, the HEV-B VP1 segments were sequenced and phylogenetic analyzed, which indicated the seven cases were all infected by enterovirus Echo 30. The sequences from those samples had homology of 95.3% - 97.1% with the epidemic strains in Zhejiang, 2004. Out of the seven cases, the sequences of XM2, XM3, XM4, XM8 throat swab samples and XM3, XM6 throat samples showed 99.4% - 100.0% homology which were different from the sequence of XM1, and the homology was 92.8% - 93.4%. Furthermore, the viruses were isolated using Vero cells from XM1, XM2, XM3, XM4 and XM8 throat swab samples, and the VP1 sequence showed more than 99.9% homology with the original specimens.</p><p><b>CONCLUSION</b>The local outbreak of aseptic encephalitis was caused by Echo 30 of enterovirus genotype B, and the epidemic strains may have different genetic background.</p>