Recent progress on cGAS-STING pathway in tumor radiotherapy / 中华放射肿瘤学杂志

Radiotherapy is widely used in the treatment of primary and metastatic malignant tumors. It is traditionally believed that the killing effect of radiotherapy on tumor is based on the direct or indirect damage of ionizing radiation to DNA. In recent years, the anti-tumor role and mechanism of anti-tumor immune response induced by ionizing radiation have captivated widespread attention and achieved significant progress. Among them, Cyclic GMP-AMP synthase (cGAS)-stimulator of interference genes (STING) pathway is considered to be one of the key regulatory hubs. cGAS is a cytoplasmic DNA receptor that can bind to tumor-derived double-stranded DNA and activate the downstream STING, thereby activating anti-tumor immune response of the host. In view of the latest progress in this field, the important role and potential mechanism of cGAS-STING pathway in radiotherapy immune effect were mainly summarized, and the application prospect of targeting cGAS-STING pathway in radiotherapy sensitization was explored.

Relationship of diabetes and prediabetes with lipid ratios in Changzhou Residents of Jiangsu Province / 上海预防医学

ObjectiveTo investigate the association of lipid ratios with diabetes and pre-diabetes in residents aged 35-75 years in Changzhou City. MethodsA multistage whole-group random sampling method was used to survey permanent residents aged 35-75 years in Tianning and Wujin districts of Changzhou City， and the study data were obtained by questionnaires， physical examination and laboratory tests. The relationship between lipid ratios and diabetes and pre-diabetes was analyzed by dichotomous logistic regression method. ResultsThe prevalence of diabetes in the surveyed population in Changzhou was 18.69%， and the prevalence of pre-diabetes was 10.53%. In the total population， the risk of pre-diabetes was significantly increased in the highest TC/HDL-C， TG/HDL-C and LDL-C/HDL-C groups， by 68%， 93% and 38%， respectively； the risk of diabetes was also significantly increased in the highest TC/HDL-C， TG/HDL-C and LDL-C/HDL-C groups， by 105%， 149% and 78%， respectively. The risk of diabetes was also significantly increased in the highest TC/HDL-C， TG/HDL-C and LDL-C/HDL-C groups， by 105%， 149% and 78%， respectively. All three lipid ratios increased in women compared to men， leading to a stronger association with increased risk of diabetes and pre-diabetes. ConclusionLipid ratios TC/HDL-C， TG/HDL-C， and LDL-C/HDL-C were correlated with the risk of diabetes and pre-diabetes in people aged 35-75 years， with TG/HDL-C having the strongest association with diabetes and pre-diabetes， and is expected to be a key predictor for assessing the development of diabetes.

Inter- and intra-observer variability for the assessment of coronary artery tree description and lesion EvaluaTion (CatLet©) angiographic scoring system in patients with acute myocardial infarction / 中华医学杂志(英文版)

BACKGROUND@#Previously, we developed a novel Coronary Artery Tree description and Lesion EvaluaTion (CatLet©) angiographic scoring system, which was capable of accounting for the variability in the coronary anatomy and assisting in the risk-stratification of patients with acute myocardial infarction (AMI). Our preliminary study revealed that the CatLet score better predicted clinical outcomes for AMI patients than the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score. However, the reproducibility of the CatLet score in both inter- and intra-observer remains to be evaluated.@*METHODS@#A total of 30 consecutive AMI patients, admitted in September of 2015, were independently assessed by two experienced interventional cardiologists to evaluate the inter-observer reproducibility of the CatLet score. Another set of 49 consecutive AMI patients, admitted between September and October in 2014, were assessed by one of the two interventional cardiologists on two occasions 3 months apart to evaluate the intra-observer reproducibility of the CatLet score. The weighted kappa was used to express the degree of agreement.@*RESULTS@#The weighted kappa values (95% confidence interval) for the intra- and inter-observer reproducibility of the CatLet Score were 0.82 (0.59-1.00, Z = 7.23, P 22). Regarding the adverse characteristics pertinent to lesions and dominance parameters, the kappa values for the inter-observer variability were 0.80 (0.56-1.00, Z = 6.47, P < 0.001) for total number of lesions, 0.57 (0.28-0.85, Z = 3.03, P < 0.001) for bifurcation, 0.69 (0.43-0.96, Z = 5.06, P < 0.001) for heavy calcification, 1.00 (0.72-1.00, Z = 6.93, P < 0.001) for tortuosity, 0.54 (0.26-0.82, Z = 3.78, P < 0.001) for thrombus, 0.69 (0.48-0.91, Z = 6.29, P < 0.001) for right coronary artery dominance, 0.69 (0.41-0.96, Z = 4.91, P < 0.001) for left anterior descending artery length, and 0.22 (0.06-0.51, Z = 1.56, P = 0.06) for diagonal size. Equivalent values for the intra-observer variability were moderate to almost perfect (range 0.54-1.00).@*CONCLUSIONS@#The reproducibility of the CatLet angiographic scoring system for evaluation of the coronary angiograms ranged from substantial to excellent. The high reproducibility of the CatLet angiographic scoring system will boost its clinical application to patients with AMI.

Relationship between factors of gross tumor volume and locoregional failure of radical intensity-modulated radiation therapy for esophageal carcinoma / 中华放射肿瘤学杂志

Objective Investigate the relationship between gross tumor volume (GTV)-related factors including GTV-T volume,the maximum thickness of the esophageal lesion plane and GTV-T volume/length(GTV-T volume divided by the length of the lesion calculated by the number of GTV-T layers) and the locoregional failure of radical intensity-modulated radiation therapy (IMRT) for esophageal carcinoma.Methods A total of 133 patients with esophageal cancer undergoing radical IMRT were enrolled.The factors related to GTV-T including GTV-T volume,the maximum thickness of the esophageal lesions,GTV-T volume/length were calculated.The relationship between GTV-T related factors and local recurrence of tumors was retrospectively analyzed.Results There was positively linear association between the locoregional failure rate of GTV-T and the volume of GTV-T.The volume of GTV-T tumor was 36 cm3,the maximum wall thickness was 2.5 cm,and the GTV-T volume/length was calculated as 5.3 cm2.These critical values could be utilized to predict the risk of locoregional failure of IMRT for esophageal carcinoma.Conclusions The GTV-T factors can be adopted to predict the local control and the risk of locoregional failure of radical IMRT for esophageal carcinoma to certain extent.

Superficial siderosis of the central nervous system caused by myxopapillary ependymoma of conus medullaris and cauda equine: a case report and literature review / 北京大学学报(医学版)

Superficial siderosis of the central nervous system (SSCNS) is a rare disorder caused by hemosiderin deposits in the subpial layers of the brain and spinal cord due to prolonged or recurrent low-grade bleeding into the cerebrospinal fluid (CSF). Central nervous system tumor could be one of the sources of bleeding. Some problems exist at present regarding the diagnosis and treatment of SSCNS in China. On account of fewer cases, the insufficient awareness of the condition, and the lack of long-term follow-up data, enough attention has not been paid to etiological diagnosis. The speculative high rate of missed diagnoses of SSCNS indicates a great disparity in the treatment from the world's advanced level. Related data of clinical and basic research need to accumulate as soon as possible to promote the clinical diagnosis and treatment of the disease. The progressive neurological deficits are involved in the typical clinical manifestations of SSCNS with a triad of bilateral symmetrical sensorineural hearing loss, cerebellar ataxia and signs of corticospinal tract dysfunction. Nevertheless, there are few patients with the triad signs at the same time, which lead to a delayed diagnosis or misdiagnosis. Detection of this disease was commonly post-mortem until the advent of MRI with signal and location characteristics, which made diagnosis easier. Siderosis appears as a hypointense rim covering the surface of the cerebellum, the brain stem, the spinal cord, similar to a black pencil line, thin on SE-T2-weighted images, thick and conspicuous on GE-T2-weighted images or on susceptibility-weighted imaging (SWI). The only effective way of treating the disorder is to identify the source of bleeding and remove it. MR examination is useful for seeking a source of bleeding too. Therefore, once superficial siderosis is considered, lesions of the central nervous system must be searched using MRI of the brain and spine. We report here a 37-year-old male diagnosed of SSCNS with the classical clinical symptoms of cerebellar ataxia, sensorineural hearing loss and myelopathy. T2-weighed MRI showed characteristic marginal hypo-intensity around the central nervous system. Etiological explorations revealed a large conus medullaris / cauda equina ependymoma filling the lumbosacral spinal canal, a myxopapillary ependymoma (MPE) confirmed by surgical resection and histopathological examination. The related literature was reviewed to ascertain the mechanism of SSCNS secondary to MPE, and to discuss the pathogenesis, clinical features, diagnosis and treatment of SSCNS. This paper aims to improve the awareness of SSCNS and diagnostic level, and to lay stress on the etiological explorations that is beneficial to the development of exact treatment plan.

Research progress on metabolic regulating cell fate / 国际生物医学工程杂志

The close link between metabolism and cell death has been getting more and more attention.Many metabolically related proteins play a key role in the programmed cell death pathway.Several proteins classically regulating cell death have been found to regulate metabolism.In addition,many metabolic intermediates are closely involved in the cascade of signal transduction pathways that influence cell death.Some metabolic checkpoints not only receive information from metabolic variables,but also transmit signals that regulate cell survival.Typically,these checkpoints respond to metabolic imbalances by activating an organelle specific or by initiating an adaptive response at the overall level of the cell,and attempts to establish a new homeostasis.However,when the metabolic disorders are extravagantly serious or prolonged in time,these checkpoints will initiate apoptosis or programmed cell death.The cross-regulation of cellular metabolism and death pathways was discussed,so as to provide clues for the development of novel pharmacological approaches by regulating the metabolism to block or induced cell death.

Clinical significance of NS1-BP expression in esophageal squamous cell carcinoma / 中华肿瘤杂志

Objective@#To investigate the clinical significance of NS1-BP expression in patients with esophageal squamous cell carcinoma (ESCC), and to study the roles of NS1-BP in proliferation and apoptosis of ESCC cells.@*Methods@#A total of 98 tumor tissues and 30 adjacent normal tissues from 98 ESCC patients were used as study group and control group, and these samples were collected in Sun Yat-Sen University Cancer Center between 2002 and 2008. In addition, 46 ESCC tissues which were collected in Cancer Institute and Hospital of Tianjin Medical University were used as validation group. Expression of mucosal NS1-BP was detected by immunohistochemistry. Kaplan-Meier curve and log-rank test were used to analyze the survival rate. Multivariate Cox proportional hazard model was used to analyze the prognostic factors. Furthermore, NS1-BP was over expressed or knocked down in ESCC cells by transient transfection. Protein levels of c-Myc were detected by western blot. Cell viability and apoptosis was analyzed by MTT assay and flow cytometry.@*Results@#Among all of tested samples, NS1-BP were down-regulated in 9 out of 30 non-tumorous normal esophageal tissues (30.0%) and 85 out of 144 ESCC tissues (59.0%), respectively, showing a statistically significant difference (P=0.012). In the study group, three-year disease-free survival rate of NS1-BP high expression group (53.2%) was significantly higher than that of NS1-BP low expression group (27.6%; P=0.009). In the validation group, the three-year disease-free survival rates were 57.8% and 25.5% in NS1-BP high and low levels groups, respectively, showing a similar results (P=0.016). Importantly, multivariate analyses showed that low expression of NS1-BP was an independent predictor for chemoradiotherapy sensitivity and shorter disease-free survival time in ESCC patients(P<0.05 for all). Furthermore, overexpressed NS1-BP in TE-1 cells repressed c-Myc expression, inhibited cell proliferation and promoted apoptosis. In contrast, knockdown NS1-BP in KYSE510 cells induced c-Myc expression, increased cell proliferation and repressed apoptosis.@*Conclusions@#NS1-BP is an independent favorable prognostic factor in ESCC. It inhibits cell proliferation and enhances cell apoptosis via repressing c-Myc. Targeting NS1-BP may be a new therapeutic strategy for ESCC patients.

Effect of DAVID system on dosimetry of linear accelerator / 医疗卫生装备

Objective To explore the effect of DAVID system on the beam dosimetry of ELEKTA Synergy accelerator. Methods Three-dimensional water phantom system was used to measure the values of percentage depth dose (PDD) in different fields,gun-trarget(G-T)in different fields and depths as well off-axis ratio(OAR)at left-right(L-R)direction when the accelerator was equipped with DAVID system or not. Results DAVID system had no effects on PDD and OAR, while influenced the absorbed dose so that the ray was attenuated by 7%.Conclusion The field parameters have not to be modified for the planning system when using DAVID system,but the dose correction has to be performed according to ray transmission factors.

Rural chronic disease patient treatment flow and cost based on intervention study in Jiangsu Province / 中国卫生政策研究

Objective:To analyze the situation of seeking medical treatment and assess the impact of interven-tion on rural chronic disease patients.A comprehensive intervention strategy was developed and implemented in rural area of Jiangsu province.Methods:According to the implementation plan,a random sampling method was adopted in Gaochun,Jingjiang and Huaiyin districts of Jingsu province to select a total of 4 261 people to be surveyed on the baseline,with 2116 people were in the intervened group and 2 145 in the controlled group,which was conducted for one year.The changes of flow tendency,times and expenses of seeking medical treatment before and after the inter-vention were analyzed.Results:After intervention,patients with chronic disease choosing primary health institutions for medical treatment has obviously improved, which was observed to be significant when compared with the con-trolled group.The average times of seeking medical treatment in primary health institutions is exceeding 10 times and which is significantly higher than before the intervention and the controlled group.After the intervention, patients, medical expenses reduced,which is significantly lower than that of the controlled group.Conclusions: Through one year of intervention,more and more patients with chronic diseases were choosing primary health institutions for medi-cal treatment.But the medical expenses have not yet achieved good control.So the support of national policy to fur-ther standardize the patients,behavior of seeking medical treatment is still needed.

Effects of gross tumor volume and positive lymph node volume on prognosis of intensity-modulated radiotherapy for esophageal squamous cell carcinoma / 中华放射肿瘤学杂志

Objective To analyze the effects of gross tumor volume(GTV-T)and positive lymph node volume(GTV-LN)on the prognosis of radical concurrent chemoradiotherapy for esophageal squamous cell carcinoma(ESCC). Methods A total of 79 patients with stage N1ESCC undergoing radical radiotherapy in our hospital from 2012 to 2015 were enrolled as subjects. GTV-T and GTV-LN were calculated by the Pinnacle39.0 treatment planning system. The receiver operating characteristic(ROC)curves were used to evaluate the value of the GTV-LN/GTV-T ratio in the prediction of local recurrence(LR)and distant metastasis(DM)of ESCC. Results The median follow-up time was 17.2 months in all patients. The ROC curves were made using the GTV-LN/GTV-T ratio. The optimal cut-off values of GTV-LN/GTV-T ratio for predicting the risk of LR and DM were 0.34 and 0.59, respectively. The statistical analysis revealed that the LR rates were 50% and 8% in patients with GTV-LN/GTV-T ratios of<0.34 and ≥0.34, respectively(P<0.01), while the DM rates were 11% and 43% in patients with GTV-LN/GTV-T ratios of<0.59 and ≥0.59, respectively(P= 0.003). Conclusions The GTV-LN/GTV-T ratio may be a predictor of LR and DM in patients with ESCC. Further studies on the GTV-LN/GTV-T ratio may help to make personalized chemoradiotherapy strategies for patients with ESCC.

An analysis of risk factors for esophageal fistula and fatal bleeding after intensity-modulated radiotherapy for esophageal cancer / 中华放射肿瘤学杂志

Objective To evaluate the incidence of and risk factors for esophageal fistula and fatal bleeding after intensity?modulated radiotherapy ( IMRT) for esophageal cancer. Methods Clinical data were collected from 128 patients with esophageal cancer who received radical IMRT in our hospital from January 2012 to December 2014. According to the incidence of esophageal fistula and fatal bleeding, those patients were divided into control group ( n= 105 ) and severe complications group ( n= 23 ) . In the severe complications group,12 patients had esophageal fistula and 11 fatal bleeding. Between?group comparison was made by χ2 test. The Cox model was used for the multivariate analysis. Results Chest and back pain in the initial diagnosis,clinical stage cT4 ,tumor type ( ulcerative) ,gross tumor volume ( GTV)>50 cm3 ,and GTV maximum diameter>2?45 cm were risk factors for esophageal fistula and fatal bleeding after radiotherapy for esophageal cancer (P=0?042,0?042,0?019,0?046,0?002).The multivariate analysis showed that tumor type ( ulcerative) and GTV maximum diameter were independent risk factors for esophageal fistula and fatal bleeding ( P=0?010,HR=0?329,95% CI:0?142?0?763;P=0?009,HR=3?805,95% CI:1?404?10?312) . Conclusions The efficacy of IMRT is severely restricted by the incidence of esophageal fistula and fatal bleeding. For patients with an ulcerative type of esophageal cancer or a GTV max diameter of>2?45 cm,the chemoradiotherapy plan should be optimized to reduce the risk of severe complications.

Research progress on anticancer therapeutics targeting telomere/telomerase / 中国肿瘤临床

Telomeres are protective caps located at the ends of human chromosomes. Telomeres shorten with each successive cell di-vision in normal human cells, whereas they are continuously elongated by human telomerase in over 85%of tumors. This simple and attractive difference steers the development of anticancer drugs targeting telomeres and telomerase. Many promising current telo-mere/telomerase-targeting agents, such as GRN163L and GV1001, showed good therapeutic effect both in preclinical studies and phaseⅠ/Ⅱclinical trials. These agents have even entered phaseⅢclinical trials in patients with various tumors. Most therapeutics are more effective when used in combination with standard chemotherapies. Moreover, pharmacological interference with tumor-cell telomere biology to reduce telomere length and/or telomere stability could enhance the effectiveness and safety of radiotherapy. Therapeutics targeting telomere/telomerase may play a key role in radiotherapy in the era of personalized medicine in the future.

Effect of Autophagy Over Liver Diseases / 中国医学科学杂志(英文版)

In recent years, increasingly evidences show that autophagy plays an important role in the pathogenesis and development of liver diseases, and the relationship between them has increasingly become a focus of concern. Autophagy refers to the process through which the impaired organelles, misfolded protein, and intruding microorganisms is degraded by lysosomes to maintain stability inside cells. This article states the effect of autophagy on liver diseases (hepatic fibrosis, fatty liver, viral hepatitis, and liver cancer), which aims to provide a new direction for the treatment of liver diseases.

Association of CKMM gene A/G polymorphism and athletic performance of uyghurnationality / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Discusses the distributive characters of the Creatine Kinase MM (CKMM) gene A/G Polymorphism in XinjiangUyghur, One hundred and fourtheen athletes and 441 general population of Uyghur were involved in the study.</p><p><b>METHODS</b>Polymerase chain reaction-restriction fragment length polymorphism was used.</p><p><b>RESULTS</b>(1) The CKMM gene A/G frequency in Uyghur general population was(AA, AG and GG) 0.497, 0.392 and 0.111, the result test by Hardy-Weinberg (H-W) equilibrium and x² = 2.72, P = 0.1, df = 2, indicated that the control group had representative. (2) AA, AG and GG genotype frequency of power-oriented athlete respectively was 0.442,0.302 and 0.256, frequency of GG genotype and G allele was higher than the control group, there were significant differences compared to thecontrol( P < 0.05, df = 2); (3) A/G genotype frequency of Endurance-oriented athletere spectively was 0.571, 0.400 and 0.029, there were nosignificant differences compared to the controls ( P > 0. 05, df = 2). (4) A/G genotype frequency of Uyghur soccer athletes respectively was0.472, 0.361 and 0.167, G allele was higher than the Endurance-oriented athlete and lower than the power-oriented athletes. and no significant differences compared to the controls( P > 0.05, df = 2).</p><p><b>CONCLUSION</b>The results indicate that the CKMM gene GG genotype and G alleleare represented in power-oriented athletes, but don't find A/G polymorphism correlation with endurance and the football sport performance.</p>

A study of radiosensitizing effect of PKM2 silencing in lung adenocarcinoma cells and xenografts / 中华放射肿瘤学杂志

Objective To investigate the impacts of pyruvate kinase M2 isoform (PKM2) silencing on the radiosensitivity of lung adenocarcinoma cell line (A549 cells) and the radiation synergy of xenografts, and to explore their mechanisms. Methods Plasmid pshRNA?PKM2 for interference with PKM2 expression was transfected into A549 cells, and empty vector?transfected cells and untransfected cells were set as con?trols. The silencing efficiency of pshRNA?PKM2 and the expression level of microtubule?associated protein 1 light chain 3(LC3) were measured by Western blot assay. The radiosensitizing effects in A549 cells and xen?ografts after PKM2 silencing were determined by colony?forming assay and xenografts growth curves. Autoph?agy formation in A549 cells and xenografts was analyzed by transmission electron microscopy, and the ex?pression level of PKM2 in xenografts was measured by immunohistochemistry. Comparison between groups was made by Student′s t?test, and the body weights of nude mice and xenograft volumes were subjected to a?nalysis of variance for continuous variables. Results Stable A549 cell lines transfected with pshRNA?PKM2 were successfully produced. Transfection with pshRNA?PKM2 significantly down?regulated PKM2 expression in A549 cells and xenografts (P= 0?? 001;P= 0?? 000). The sensitizer enhancement ratios for A549 cells and xenografts were 1?? 47 and 2?? 00, respectively. Interference with PKM2 expression enhanced radiation?in duced autophagy formation and significantly increased the ratio of LC 3 ? II / I ( P= 0.000 1 ) . Conclusions Silencing of PKM2 expression may enhance the radiosensitivity of A549 cells and xenografts by regulation of autophagy, which holds promise for becoming an effective radiosensitizing target for non?small cell lung canc?er, but still needs to be confirmed by further studies.

Effects and underlying mechanisms of homologous recombina-tion-associated protein XRCC3 on esophageal squamous-cell carci-noma radiotherapy response / 中国肿瘤临床

Objective:To investigate the effects and underlying mechanisms of XRCC3 on esophageal squamous-cell carcinoma (ESCC) radiotherapy response. Methods:Expression levels of XRCC3 were detected by reverse transcription PCR, Western blot, and immunohistochemistry. We knocked down XRCC3 with lentiviral infection in ESCC cells. Cell apoptosis was examined by flow cytom-etry. DNA damage and telomere dysfunction-induced foci were determined by immunofluorescence. Results:The expression levels of XRCC3 in ESCC cells and tissues were higher than those in normal esophageal epithelial cells and corresponding adjacent noncancer-ous esophageal tissues. Knockdown of XRCC3 in ESCC cells substantially increased the therapeutic efficacy of radiation. We demon-strated that the radiation resistance of XRCC3 was attributed to the XRCC3-maintaining telomere stability, which reduced ESCC cell death through radiation-induced apoptosis. Conclusion: Our data suggested that XRCC3 protects ESCC cells from ionizing radia-tion-induced DNA damage and death by enhancing telomere stability. Thus, XRCC3 can be used as a promising therapeutic target for ESCCs.

Important Signs in Musculoskeletal MRI.

The purpose of this article is to review the common MRI signs of musculoskeletal pathology. In this article, 15 classic MRI signs used in musculoskeletal radiology are presented and described. These signs include the anterior drawer sign, bone bruise sign, bow tie sign, celery stalk anterior cruciate ligament (ACL), cyclops lesion, deep lateral femoral notch sign, double line sign, double Oreo cookie sign, double posterior cruciate ligament (PCL) sign, fat-blood interface (FBI) sign, fragment in notch sign, split fat sign, T-sign, target sign, and yo-yo on a string sign. It is important to recognize common signs in musculoskeletal MRI and understand the underlying pathologies for accurate image interpretation.

Sonographic Evaluation of Subscapularis Tendon Tears with Surgical Correlation.

Aims: The purpose of this study was to evaluate the ability of ultrasound in detecting subscapularis tendon pathology with operative correlation. Methodology: A retrospective study was conducted on 86 patients who had shoulder ultrasound prior to surgical repair from January 2006 to August 2008. All sonographic examinations and surgical reports were reviewed. Sonographic evaluation of subscapularis tendon, including normal, tendinosis, partial thickness tear, full thickness tear, and complete tear were correlated to operative reports. Results: Of the 86 patients, 19 patients had surgically proven abnormal subscapularis tendons. There was 100% ultrasound concordance in tendinosis (n = 1), 100 % ultrasound concordance in partial thickness tears (n =3), 88 % ultrasound concordance in full thickness tears (n = 8), 57 % ultrasound concordance in complete tears (n = 7). Overall, there was 79% ultrasound concordance in diagnosing subscapularis tendon pathology when surgery is used as a gold standard. Conclusion: Ultrasound is useful in the evaluation of the subscapularis tendon. The sonographic findings of tendinosis and partial thickness tears correlate best with surgery. However, ultrasound may underestimate complete tears.

Effect of repeated sintering on the color and translucency of dental lithium disilicate-based glass ceramic / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of repeated sintering on the color and translucency of dental lithium disilicate-based glass ceramic.</p><p><b>METHODS</b>Thirty disc specimens (10 mm in diameter, and 1.00 mm ± 0.01 mm in thickness) were fabricated using an IPS e.max Press HT A2 ingot and then randomly divided into six groups (SO, S1, S2, S3, S4, and S5) (n = 5). Each group was sintered 0, 1, 2, 3, 4, and 5 times individually according to the manufacturer's recommendation. After polishing, ultrasonic cleaning, and drying, the color parameters (L*, a*, and b* values) and transmittance (τ) of all the specimens were measured using a ShadeEye NCC dental colorimeter and a TM-2 spectrophotometer, respectively. Subsequently, C*ab and ΔE were calculated. The results were statistically analyzed using SPSS 17.0 software for ANOVA and LSD.</p><p><b>RESULTS</b>After repeated sintering, the L* value significantly decreased (P < 0.05), and the a*, b*, and C*ab values initially increased and then decreased (P < 0.05). The color parameters (L*, a*, and b*) and the C*ab values of group S3 were higher than those of the other groups. The τ values initially increased and then decreased (P < 0.05), and these values were optimal when sintered twice. In terms of transmittance (τ), statistical differences existed between the following groups: S0 and S2, S0 and S3,.S2 and S5, and S3 and S5 (P < 0.05). Compared with group S0, the color differences ΔE were 0.89 minimally and 2.01 maximally after different sintering times, which can be clinically acceptable.</p><p><b>CONCLUSION</b>Repeated sintering can affect the color and translucency of the IPS e.max Press lithium disilicate-based glass ceramic, but the color difference can be clinically acceptable.</p>

Protoplasts isolation, purification and plant regeneration of Pinellia cordata / 中国中药杂志

The main factors which affected the isolation, purification and cultivation of Pinellia cordata protoplasts from leaves were studied. The results indicated that the optimum enzyme solution for P. cordata leaves was 13% CPW + 1.0% Cellulose +0.1% Pectolase, at pH 6.0, temperature (25-28 degrees C ) for 4 h. The sucrose density gradient centrifugation was adopted to purificate the protoplasts collected, when 25% sucrose was used as mediator, centrifugating at 500 rpm for 10 min. When the protoplasts were shallow liquid and liquid-solid double layer cultured on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA + 13% mannitol at the density of 2.5 x 104 protoplasts/mL, or fed and nursed cultured at the density of 100-500 protoplasts/mL, cell division could be observed for 3 days; granular calli appeared for 30 days. Calli was proliferated on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA solidified by 0.55% agar, and differentiated and regenerated after 5-6 months. Plant generation of P. cordata is successfully established.