[Efficacy of venetoclax-based induction regimen in newly diagnosed pediatric acute myeloid leukemia].

Objective: To explore the efficacy of venetoclax-based induction regimen for children with newly diagnosed acute myeloid leukemia (AML). Methods: Children with newly diagnosed AML in Beijing Children's Hospital Affiliated to Capital Medical University and Baoding Hospital Affliliated to Capital Medical University from November 2019 and December 2023 were prospectively included. The patients were divided into DAH group (daunorubicin, cytarabine and homoharringtonine) and VAH group (venetoclax, cytarabine and homoharringtonine) according to induction regimen. The clinical data of the children were collected, the clinical characteristics and induced remission rate between the two groups were compared, and multivariate logistic regression was used to analyze the related factors affecting the induced remission rate. Results: A total of 135 patients were enrolled, including 96 cases in the DAH group (54 males and 42 females), aged [M (Q1, Q3)] 6.4 (3.9, 11.6) years and 39 cases in the VAH group (26 males and 13 females), aged 8.0 (6.2, 13.2) years. Among patients initially diagnosed with low-medium risk AML, the morphologic complete remission rates were 94.7% (18/19) in the VAH group and 84.4% (38/45) in the DAH group, respectively, and the negativity conversion rates of minirnal residual disease (MRD) were 57.9% (11/19) and 46.7% (21/45), respectively, with no statistically difference (all P>0.05). Among patients initially diagnoised with high-risk AML, the morphologic complete remission rates in the VAH group was higher than that in the DAH group [95.0% (19/20) vs 70.6% (36/51), P=0.027], and negativity conversion rates of MRD were 45.0% (9/20) and 33.3% (17/51), respectively, with no statistically difference (P=0.359). The induction regimen (venetoclax, cytarabine and homoharringtonin) was beneficial to morphological remission (OR=0.126, 95%CI: 0.025-0.629). FLT3 mutation was not conducive to morphological remission (OR=5.832, 95%CI: 1.778-19.124) and negative MRD (OR=4.166, 95%CI: 1.396-12.433). Conclusion: Venetoclax-based induction regimen is more effective than traditional chemotherapy regimen for newly diagnosed pediatric AML.

[Advances in the application of the bony window technique in endodontic microsurgery].

The bony window technique refers to cutting the intact bone plate to form a bone window and a free bone block to get access to lesions under the bone. At the end of the surgery, the dislocated bony lid needs to be repositioned to its original position. In endodontic microsurgery, compared with conventional osteotomy, the bony window technique has the advantages of improving the view of surgery and operability, reducing postoperative bone defects, promoting bone healing, and maintaining the integrity of the jaw outline. Accurate positioning and preparation of the bony window are important prerequisites for subsequent operations during the surgery, but it's difficult in some situations, such as when the operative area is located posteriorly or the bone cortex on the lesion surface is thick and intact. What's more, whether the free bone block can be stabilized in situ after repositioning is closely related to the prognosis of the surgery. The complementary application of digital navigation technology and bone cavity filling materials may help to improve the bony window technique and provide more possibilities for the retention of affected teeth in difficult cases.

Differentiation of giant cell tumours of bone, primary aneurysmal bone cysts, and aneurysmal bone cysts secondary to giant cell tumour of bone: using whole-tumour CT texture analysis parameters as quantitative biomarkers.

AIM: To determine whether computed tomography (CT) texture analysis parameters can be used as quantitative biomarkers to help differentiate giant cell tumour of bones (GCTs), primary aneurysmal bone cysts (PABCs), and aneurysmal bone cysts (ABCs) secondary to giant cell tumours of bone (GABCs). MATERIALS AND METHODS: One hundred and seven patients with 63 GCTs, 31 PABCs, and 13 GABCs were analysed retrospectively. All patients underwent preoperative CT. Two radiologists independently evaluated the qualitative features of the CT images and extracted texture parameters. Patient demographics, qualitative features, and texture parameters among GCTs, PABCs, and GABCs were compared statistically. Differences in these parameters between ABCs and GCTs were also assessed. ROC curves were obtained to determine optimal parameter values. RESULTS: The best preoperative CT parameters to differentiate GCTs, PABCs, and GABCs included one qualitative feature (location around the knee) and four texture parameters (95th percentile, maximum intensity, skewness, and kurtosis). Age and three texture parameters (5th percentile, inhomogeneity, and kurtosis) enabled statistically significant differentiation between GCTs and ABCs. Combination of the above four parameters generated the largest area under the ROC curve (AUC) for the differentiation of GCTs and ABCs. CONCLUSION: CT texture analysis parameters can be used as quantitative biomarkers for preoperative differentiation among GCTs, PABCs, and GABCs.

[Causes, diagnosis and treatment strategies for dental pulp calcification].

Dental pulp calcification can lead to root canal stenosis or obliteration. It is usually difficult to negotiate the root canal if the affected tooth needs to be treated and intraoperative complications are easily brought about during the root canal treatment. The etiologies of dental pulp calcification are complicated and careful considerations should be given to the diagnosis and treatment. Only by weighing the advantages and disadvantages can appropriate treatment plan be chosen. Based on the literature and authors' clinical experiences, the present article summarizes the causes, pathogenesis, diagnosis and treatment strategies of dental pulp calcification, in order to provide some references in diagnosis and treatment for the dental clinicians.

[Relationship between white matter lesions and theresponse of cerebral spinal fluid tap test and clinical features in the patients with idiopathic normal pressure hydrocephalus].

Objective: To explore the relationship between white matter lesions and clinical features and response of cerebral spinal fluid (CSF) tap test in patients with idiopathic normal pressure hydrocephalus(iNPH). Methods: Possible iNPH patients were enrolled from outpatients and inpatients in Peking Union Medical College Hospital between 2014 and 2019. All patients underwent detailed neuropsychological and walking assessments, CSF tap test, as well as head magnetic resonance imaging. The Fazekas score of white matter lesions, the fractional anisotropy (FA)and mean diffusivity (MD) values of regions of interest by means ofdiffusion tensor imaging (DTI) were compared between CSF tap test positive and negative response groups. The correlation between DTI parameters and clinical characteristics was analyzed. Results: Forty-three patients (29 male and 14 female, age range: 52-79 years] wererecruited.Compared with the negative group, patients in the positive group tended to have higher Fazekas score of periventricular white matter(U=108.00, P=0.03), higher MD value of the region near anterior horn of left lateral ventricles[(1.14±0.27)×10-9mm2/s vs (0.85±0.08) ×10-9mm2/s, P=0.003], lower FA value of the region near anterior horn of the right lateral ventricles[(0.20±0.07)vs(0.27±0.09), P=0.058], and higher MD value near the posterior horn of right lateral ventricle [(1.17±0.34)×10-9mm2/s vs (0.95±0.01)×10-9mm2/s, P=0.003]. FA and MD were significantly correlated with motor function, cognitive and functional scores, and iNPH grading scale (iNPHGS) scores(all P<0.05). Conclusions: The white matter lesions might be one of the pathogeneses of lNPH and apathological changewhich can be reversed by CSF drainage. More white matter lesions should not be the contraindication of CSF drainage surgery.

[Early outcome of valve sparing aortic root replacement with partial upper sternotomy].

Objective: To examine the early outcome of valve sparing aortic root replacement with reimplantation technique (David procedure) with partial upper sternotomy. Methods: From April 2016 to April 2020, 31 patients underwent valve sparing aortic root replacement under partial upper sternotomy at Vascular Surgery Center, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. There were 28 males and 3 females, aging (44±13) years (range: 11 to 65 years). Preoperative aortic regurgitation was found greater than moderate in 15 patients, moderate in 6 patients and less than moderate in 10 patients. The diameter of aortic annulus was (26±3) mm (range: 21 to 34 mm), the diameter of aortic sinus was (51±6) mm (range: 41 to 68 mm), the diameter of ascending aorta was (43±8) mm (range: 26 to 62 mm). The preoperative ejection fraction was (65±4) % (range: 59% to 72%) and left ventricular end-diastolic diameter was (55±6) mm (range: 42 to 68 mm). All cases were treated with David Ⅰ procedure, including simple David procedure in 26 patients, David+ascending aorta and partial aortic arch replacement in 3 patients, David+thoracic endovascular aortic repair in 1 patient, David+stent elephant trunk implantation in 1 patient. Results: The operation time, cardiopulmonary bypass time and aortic cross-clamping time were (330±58) minutes (range: 214 to 481 minutes), (138±23) minutes (range: 106 to 192 minutes) and (108±17) minutes (range: 82 to 154 minutes), respectively. There were no death and serious complications (stroke, myocardial infarction, renal insufficiency, severe infection, etc.). The postoperative drainage volume within 24 hours was (314±145) ml (range: 130 to 830 ml). The intubation time was (14±3) hours (range: 8 to 21 hours), and the ICU time was (M(QR)) 2.1(1.5) days (range: 1.0 to 5.0 days). Eight patients had no blood transfusion, the proportion of red blood cell use was 9.7% (3/31), plasma use was 22.6% (7/31), and platelet use was 71.0% (22/31). The postoperative left ventricular ejection fraction was (62±4)% (range: 54% to 69%), and left ventricular end-diastolic diameter was (48±4) mm (range: 39 to 56 mm). After operation, aortic regurgitation was significantly improved, with no more than moderate regurgitation, small to moderate regurgitation in 3 patients, minor regurgitation in 3 patients, micro regurgitation in 12 patients and no regurgitation in 13 patients. The follow-up period was 3.5(6.1) months (range: 2.0 to 39.0 months). Echocardiographic follow-up data were obtained in 26 cases, including moderate regurgitation in 1 patient, small to moderate regurgitation in 9 patients, minor regurgitation in 5 patients, micro regurgitation in 6 patients and no regurgitation in 5 patients. There were no major adverse cardiovascular events and aortic events during the follow-up period. No patient was reoperated for aortic regurgitation. Conclusion: Valve sparing aortic root replacement under partial upper sternotomy is safe and feasible, and the early result is satisfactory.

Population-based evaluation of the risk factors and prognosis among renal cell carcinoma patients with initially diagnosed lung metastases.

OBJECTIVES: To evaluate risk factors and prognosis of lung metastases in patients with renal cell carcinoma (RCC) based on the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: 56,617 patients with RCC were selected from the SEER database. Based on univariate and multivariate logistic regression, the risk factors for developing lung metastases were derived. 2906 patients were initially diagnosed with lung metastases, and then were used to research the prognostic factors. Multivariable Cox regression analyses were performed for the prediction of cancer-specific mortality. RESULTS: In total, 2906 RCC patients were initially diagnosed with lung metastases. The prevalence of lung metastases in RCC was approximately 5% with poor survival. Aging, male, other race (American Indian/AK native, Asian Pacific islander) uninsured status, bilateral tumor, collecting duct, higher T stage, local lymph node metastases, higher tumor grade, and evidence of other distant metastases were significantly associated with developing lung metastases at diagnosis. Age >70 years-old, black, female, bilateral tumor, T4 stage, higher tumor grade, local lymph node metastases, collecting duct, and evidence of bone, liver, or brain metastases were related to higher risk of mortality. Blacks and female have lower odds of developing lung metastases at the time of diagnosis both in crude and adjusted logistic regression. Meanwhile, blacks and female showed higher risk of mortality compared with whites and male in Cox regression analyses. CONCLUSION: Several factors related to the development and prognosis of lung metastases were revealed, especially black people and female gender have lower risk of developing lung metastatic RCC at initial diagnosis but have higher risk of mortality. These may provide preventive guidelines for the screening and treatment of lung metastases in patients with renal cell carcinoma.

Diverse bacterial profile in extraradicular biofilms and periradicular lesions associated with persistent apical periodontitis.

AIM: To characterize the bacterial community present in the extraradicular biofilm and periradicular lesions associated with persistent apical periodontitis. METHODOLOGY: Eighteen adult patients who presented with persistent periradicular lesions after root canal treatment and scheduled for endodontic surgery were selected. During surgery, extraradicular samples of biofilms and periradicular lesions were collected. Ten pairs of periradicular lesions and extraradicular biofilm samples were randomly selected for ribosomal 16S rRNA cloning and sequencing. A Wilcoxon's rank-sum test was used to compare total bacterial counts and the levels of individual genera and species between the two groups (P < 0.05). RESULTS: Overall, seventy-three phylotypes belonging to six different phyla were identified from 1000 sequenced clones. Mogibacterium timidum, Streptococcus intermedius and Enterococcus faecalis predominated in both extraradicular biofilm and periapical lesions. Propionibacterium propionicus, Abiotrophia adiacens, Peptostreptococcus prevotii, Campylobacter gracilis and Pseudomonas aeruginosa were found in significantly higher levels in the extraradicular biofilm than periapical lesions, whilst Parvimonas micra and Atopobium rimae were more abundant in periapical lesions (P < 0.05). CONCLUSIONS: The microbial profile of extraradicular biofilms differed from periapical lesions, indicating the presence of diverse bacterial populations in these regions. Several genera and species were significantly associated with the formation of extraradicular biofilms.

Effective corrosion inhibition of mild steel by eco-friendly thiourea functionalized glucosamine derivatives in acidic solution.

In the view of environmental protection and sustainable development, the application of green effective inhibitors for metal corrosion in industry field is of great significance. In this work, two thiourea functionalized glucosamine derivatives, 5-hydroxy-1-phenyl-4-(1,2,3,4-tetrahydroxybutyl)imidazolidine-2-thione (GA-1) and 1-phenyl-3-(2,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)thiourea (GA-2), were synthesized as eco-friendly corrosion inhibitors for mild steel (MS) in 1 M HCl solution, and their inhibition performance were evaluated by electrochemical tests and surface analyses. The electrochemical tests and surface analyses indicate that both GA-1 and GA-2 have high inhibition performance. Especially for GA-2, the inhibition efficiency reaches 97.7% with a concentration of 0.64 mM. Theoretical calculations were also conducted to elucidate the adsorption mechanism of GA-1 and GA-2 on MS surface.

VASPIN reduces inflammation and endoplasmic reticulum stress of renal tubular epithelial cells by inhibiting HMGB1 and relieves renal ischemia-reperfusion injury.

OBJECTIVE: Renal ischemia-reperfusion injury (IRI) is a clinically common issue and the resulting acute kidney injury (AKI) seriously threatens the patient's life. Therefore, prevention and treatment of renal IRI are the key to alleviating AKI in such patients. The purpose of this study was to explore the effects of VASPIN on mouse renal IRI and human renal proximal tubular epithelial cells (HK-2 cells) to provide a new direction for the treatment of clinical renal IRI. MATERIALS AND METHODS: C57/BL6 mice were used to construct a renal IRI model and recombinant mouse VASPIN was subcutaneously injected to determine whether VASPIN can alleviate renal IRI in mice by histological examination and detection of mouse urine and serum related indicators. In addition, HK-2 cells were cultured and an IRI model was constructed at the cellular level by hypoxia reoxygenation to examine the effect and mechanism of VASPIN on endoplasmic reticulum stress (ERS) in HK-2 cells. RESULTS: Results revealed that in VASPIN-treated mice, edema of renal tubular epithelial cells was significantly improved and renal injury markers netrin-1 and L-FAPB were decreased in urine. In addition, VASPIN also reduced the expression of inflammatory factors in mouse serum and the level of oxidative stress in kidney tissue. The expression of ERS-related molecules (GRP78, ATF6, caspase12, and CHOP) in HK-2 cells treated with VASPIN was significantly reduced and VASPIN decreased the expression of the pro-inflammatory factor HMGB1. Moreover, VASPIN promoted the activity of the Nrf2/ARE/HO-1 signaling pathway and inhibited the NF-кB signaling pathway by inhibiting HMGB1. CONCLUSIONS: VASPIN reduces inflammation and ERS levels in kidney tissue and attenuates renal IRI by activating the Nrf2/ARE/HO-1 signaling pathway and inhibiting the NF-кB signaling pathway via inhibition of HMGB1.

[Circulating endothelial microparticles for prediction of therapeutic effect in advanced lung cancer].

Objective: To explore the correlation of endothelial microparticles and progression of advanced lung cancer, and its predictive value in therapeutic effect. Methods: The data of patients with advanced lung cancer in the Oncology Department of Frist Medical Center of Chinese PLA General Hospital from October 2018 to May 2019 were collected. Blood routine, lactate dehydrogenase (LDH), tumor markers, and circulating endothelial microparticles (CD105+ EMPs) were measured before treatment. Flow cytometry was used to detect the number of CD105+ EMPs, and multivariate regression analysis was used to study the predict factors of advanced lung cancer progression. Results: A total of 88 patients were recruited in the study, including 60 in the objective response (OR) group and 28 in the disease progression (PD) group. There were no significant differences in gender, age, basic diseases, tumor stage, cancer type and therapeutic intervention between two groups, while there were significant differences in tumor marker, LDH, total microparticles (MPs), and endothelial microparticles (CD105+ EMPs) between two groups (P<0.05). In the multivariate regression analysis, CD105+ EMPs ≥70 events/µl (OR=3.623, 95%CI=1.345~9.761, P=0.011) and LDH (OR=1.008, 95%CI=1.001~1.015, P=0.032) were able to predict the progression of advanced lung cancer. A predictive model of advanced lung cancer progression was established based on the multivariate regression results. The area under the receiver operating characteristic curve (AUC) was 0.729 (95%CI=0.620~0.837, P=0.001), the sensitivity was 32.1%, the specificity was 91.6%, the positive predictive value was 64.2%, and the negative predictive value was 74.3%. Conclusion: Circulating endothelial microparticles are associated with the progression of advanced lung cancer, it combined with LDH can predict the therapeutic effect of advanced lung cancer.

Tumor-derived exosomal miR-103a-2-5p facilitates esophageal squamous cell carcinoma cell proliferation and migration.

OBJECTIVE: This study aimed to identify the different expression of microRNAs (miRNAs) in the plasma derived exosomes of patients with esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: A total of 9 patients with ESCC and 9 patients with benign diseases were involved. miRNA sequencing was performed to screen differential expression of microRNAs in plasma exosomes between patients with ESCC and controls. The function of miRNA on proliferation and migration abilities was determined by CCK-8 analysis, wound scratch and transwell test. Predicted target genes were screened by databases and confirmed by RT-qPCR. RESULTS: We identified a total of 10 miRNAs (7 upregulated and 3 downregulated) that were differentially expressed in plasma exosomes between patients with ESCC and control patients (fold change, FC ≥ 2.0 or ≤ -2.0, p ≤ 0.05) by miRNA sequencing. Ten miRNAs were detected by qRT-PCR to verify the results of the miRNA sequencing. MiR-103a-2-5p demonstrated the most significant differential expression in both exosomes of ESCC cell lines and plasma of patients as compared with control patients and was therefore selected for subsequent functional experiments. Overexpression of miR-103a-2-5p promoted proliferation and migration in TE-1 cells, whereas inhibition of miR-103a-2-5p suppressed proliferation and migration in KYSE-150 cells. Exosomes extracted from the cells transfected with miR-103a-2-5p mimics significantly increased the proliferation and migration of two ESCC cell lines. Two genes, CDH11 and NR3C1 were identified as predicted targets of miR-103a-2-5p by the bioinformatics tools TargetScan, MiRanda, and mirDIP and RT-qPCR. CONCLUSIONS: Our results shed light on how exosomal miR-103a-2-5p can promote proliferation and migration of ESCC cells and may represent a potential target for ESCC therapies.

FAM83H overexpression predicts worse prognosis and correlates with less CD8+ T cells infiltration and Ras-PI3K-Akt-mTOR signaling pathway in pancreatic cancer.

BACKGROUND: Family with sequence similarity 83 members H (FAM83H) is one member of Family with sequence similarity 83 (FAM83) family, which possess oncogenic properties in several types of cancer. However, the potential function of FAM83H in pancreatic cancer (PC) still remain unknown. AIM: This study aims to explore the role of FAM83H during pancreatic carcinogenesis and the regulation of immune infiltration in PC. METHODS: In the current study, the clinical significance and potential biological of FAM83H were evaluated by bioinformatics analysis. Possible associations between FAM83H expression and tumor immunity were analyzed using ESTIMATE algorithm and single-sample gene set enrichment analysis (ssGSEA). RESULTS: FAM83H expression was significantly upregulated in tumor tissues, and positively associated with higher histologic grade, tumor recurrence, and worse prognosis. FAM83H overexpression is notably associated with KRAS activation. And functional enrichment analysis demonstrated that FAM83H may be involved in positive regulation of cell proliferation and migration, Ras protein signal transduction, regulation of cell-matrix adhesion, epithelial to mesenchymal transition (EMT), TGF-ß receptor signaling in EMT, and activated NOTCH transmits signal to the nucleus. ESTIMATE algorithm and ssGSEA demonstrated that FAM83H overexpression suppressed the infiltration and antitumor activity of tumor-infiltrating lymphocytes (TILs), especially for CD8+ T cells. Besides, FAM83H overexpression significantly correlated with low expression of TIL-related gene markers (e.g. CD8A, CD8B, CD2, CD3D, and CD3E). CONCLUSION: The study suggests that FAM83H overexpression predicts poor prognosis and correlates with less CD8+ T cells infiltration and Ras-PI3K-Akt-mTOR signaling pathway in PC.

Inhibitive and adsorption behavior of thiadiazole derivatives on carbon steel corrosion in CO2-saturated oilfield produced water: Effect of substituent group on efficiency.

Three thiadiazole derivatives with different substituent groups, 2-(benzylthio)-5-methyl-1,3,4-thiadiazole(BMT), 2-(benzylthio)-5-(butylthio)-1,3,4-thiadiazole(BBT), and 5-(benzylthio)-1,3,4-thiadiazole-2-thiol(BTT), were synthesized and studied as the corrosion inhibitors for N80 carbon steel in CO2-saturated oilfield produced water. It is found that the synthesized thiadiazole derivatives could effectively inhibit the corrosion of N80 carbon steel by chemisorption. The corrosion inhibition performance of the organic compounds is in the order: BTT > BBT > BMT. The theoretical calculations indicate that the tautomeric transformation from thiol-BTT to thione-BTT may be responsible for the high inhibition performance of BTT.

[Depletion of PRDM9 inhibited the osteogenic differentiation potential of periodontal ligament stem cells].

Objective: To investigate the effect of PR domain zinc finger protein 9 (PRDM9), one of the histone methylated transferases, on osteogenic differentiation ability of periodontal ligament mesenchymal stem cells (PDLSC). Methods: PDLSC with PRDM9 gene knocked down by PRDM9 shRNA using recombinant lentiviral vector were allocated into the PRDM9sh group, and the transfected shRNA was as the control group. The gene expression efficiency was evaluated by reverse transcription polymerase chain reaction (RT-PCR). Alkaline phosphatase activity (ALP), alizarin red staining, mineralization and osteocalcin, which belongs to osteogenic differentiation markers detected by RT-PCR and Western blotting to detect the osteogenic differentiation ability of stem cells from periodontal ligaments in vitro. In vivo, PRDM9sh and control group cells was transplanted into the dorsal dermal to explore the osteogenesis. The area percentage of new osteogenic tissue was calculated by image pro software and statistically analyzed. Results: RT-PCR results showed that the relative expression of PRDM9 gene in PRDM9sh (0.460±0.017) was significantly lower than that in control group (1.000±0.107) (P<0.05). The results of ALP activity determined at 5 days postinduction in a significant decrease in PRDM9sh cells (0.762±0.063) compared with control group (1.225±0.058) (P<0.01). Alizarin red staining induced by osteogenesis at 2 weeks and 3 weeks showed that the staining of PRDM9sh was significantly lighter than that in control group. Quantitative calcium analysis results showed that the calcium ion concentration induced by osteogenesis at 2 weeks and 3 weeks [(0.071±0.004), (0.075±0.001)] in PRDM9sh was significantly lower than that in control group at 2 weeks and 3 weeks [(0.282±0.006), (0.485+0.004)] (P<0.01). RT-PCR results showed that the relative expression of osteocalcin mRNA in PRDM9sh (1.059±0.148) was significantly lower than that in control group at 2 weeks (2.542±0.190) (P<0.01). Western blotting results showed that osteocalcin expression in PRDM9sh was significantly lower than that in control group at 1 and 2 weeks after osteogenesis induction. Animal transplantation experiments results indicated that PRDM9 significantly inhibited the osteogenesis of PDLSC in vivo, and the proportion of osteogenic area calculated showed that the osteogenic capacity of PRDM9sh [(3.8±2.41)%] was significantly lower than that in control group [(24.54±7.06)%](P<0.05). Conclusions: Depletion of PRDM9 repressed the osteogenic differentiation of stem cells from periodontal ligament in vitro and in vivo.

[Value of MRI in the pre-operative diagnosis and classification of oblique vaginal septum syndrome].

Objective: To explore the role of MRI in the pre-operative diagnosis and classification of oblique vaginal septum syndrome (OVSS) . Methods: A retrospective analysis of the clinical records and pre-operative MRI images of 19 patients with surgery proved OVSS was carried out. Two experienced radiologists reviewed the pre-operative pelvic MRI of the 19 patients in consensus blind to the surgery results. Characteristics including malformations of the uterus, cervix and vagina, the diagnosis of the disorder and classification were evaluated. Pre-operative MRI diagnosis and classification were correlated with surgical findings. Results: Mean age of onset of symptoms for the 19 patients was 15 years (ranged 9-25 years) , and mean age of menarche was 12 years. Ten patients suffered from dysmenorrhea or lower abdominal pain, 5 patients complained of vaginal discharge, 3 patients had a history of irregular menstruation, 1 patient suffered from primary infertility. All 19 patients showed uteri didelphys. Eighteen patients showed vaginal oblique septum.One patient showed cervical atresia.MRI was completely correlated with the surgery in the pre-operative diagnosis of OVSS. MRI classification was in line with surgery in 17 patients, including 9 patients with imperforate septum (typeⅠ) , 6 patients with perforate septum (type Ⅱ) , 1 patient with imperforate septum and cervical fistula (type Ⅲ) , and another one with cervical agenesis (type Ⅳ) . One case of type Ⅱ was misdiagnosed as type Ⅰ, another one of type Ⅰ was misdiagnosed as type Ⅲ. Pre-operative MRI classification was correlated with surgery in 17 out of 19 patients. Conclusion: Pre-operative MRI allows excellent manifestation and accurate diagnosis of OVSS, and could also facilitate the evaluation of the classification.

[Metallurgic behavior and mechanical property of nickel-titanium endodontic files made by 3 heat treatment techniques].

Objective: To compare the phase transformation behavior, bending property and cyclic fatigue resistance of CM-wire, R-phase and M-wire nickel-titanium endodontic files treated by 3 heat treatment techniques. Methods: Hyflex CM (25 mm, 25#/0.06) made from CM wire, TF (25 mm, 25#/0.06) made from R-phase heat treatment, ProTaper Next X2 (25 mm, tip size 25#/0.06) made from M-wire, Mtwo (25 mm, 25#/0.06) and ProTaper F2 (25 mm, tip size 25#/0.08) made from conventional nickel-titanium wire were chosen. Five of each files were chosen for differential scanning calorimetric (DSC) evaluation (n=5). The specimens were prepared from adjacent portions of the shaft. The weight and length were typically (20±1) mg and 2-3 mm. Another eight of the 5 nickel-titanium files were undergone cantilever-bending test, respectively (n=8). Further ten of the 5 instruments were submitted to the cyclic fatigue test by using a simulated metal root canal (n=10). The data of M(s), M(f), A(s), A(f), ΔH, bending load, number of cyclic fatigue (NCF), fragment length were analyzed using one-way analysis of variance at a significance level of P<0.05. Results: The A(f) of Hyflex CM [(60.27±0.94) ℃] and ProTaper Next [(51.40±0.32) ℃] were higher than body temperature of 37 ℃. The bending load values at 3.0 mm deflection of Hyflex CM [(0.867±0.074) N], TF [(1.275±0.146) N], Mtwo [(2.281±0.426) N], ProTaper Next [(3.104±0.252) N] and ProTaper [(4.227±0.483) N] increased gradually and significantly. The NCF of Hyflex CM (582±99), TF (427±85), ProTaper Next (158±22), Mtwo (129±32) and ProTaper (65±20) decreased gradually. Conclusions: The 3 heat treatment techniques exert tremendous influence on the phase transformation behavior and mechanical characteristics of the files, which demonstrate improved bending property and cyclic fatigue resistance than the conventional ones.

[Role of the operating microscope in diagnosis and treatment of endodontic diseases].

The excellent magnification and illumination of the operating microscope not only helps to improve the quality of conventional root canal therapy, but also plays an important role in the diagnosis and treatment of the difficult cases of endodontic diseases. It has an irreplaceable position over other equipment especially for the treatment of root canal therapy complications and the apical surgery. The structure and operation of the operating microscope are relatively complicated. The proficiency of the dentist may influence the evaluation of its clinical application effect. Based on the review of literature and author's clinical experience, this paper evaluates the role of operating microscope in the diagnosis and treatment of endodontic diseases.

[Study on the incidence of lateral canals and sealing quality in the apical third roots of permanent teeth with failed endodontic treatments].

Objective: To investigate the association between the frequency and filling rate of lateral canals and the sealing quality in the apical third roots of the permanent teeth with failed endodontic treatments, so as to explore the failure factors of root canal therapy. Methods: Clinical records of the permanent teeth with failed endodontic treatments were collected from the Department of Endodontics, Capital Medical University School of Stomatology during a period of 2 years. The teeth were diagnosed as chronic apical periodontitis and then undergone endodontic microsurgery. The sealing quality of the apical root canal was observed by means of periapical radiographs. The surgical treatments were performed and the resected root apices were collected. The samples were scanned by micro-computed tomography and the 3D volume rendered images of the resected root apices were reconstructed. Moreover, the frequency and the filling rate of lateral canals in the apical third roots were calculated. The potential relationship between tooth position and the presence of lateral canals was evaluated. Results: Totally 89 teeth with 89 root apices met the inclusion criteria and were included in the present study. The rate of correct-filling, underfilling and overfilling was 40% (36/89), 32% (28/89), and 28% (25/89), respectively, examined by periapical radiographs. Amongst all of the 89 samples, lateral canals were found in 44 samples. The incidence of apices with lateral canals was 49% (44/89). Furthermore, 3 out of 44 samples were fully filled with material in the lateral canals, and the rest 41 samples showed no filling materials. The filling rate of the lateral canals was 7% (3/44). However, no significant difference was detected between the tooth position and the presence of lateral canals (P>0.05). Conclusions: The sealing quality of the apical third roots in permanent teeth with failed endodontic treatments was not good enough. The incidence of apices with lateral canals was high, but the filling rate of the canals was low. Further studies are needed to explore the relationship between lateral canals and the failure of endodontic treatment.