OBJECTIVE: To predict the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training based on the modified Wright learning curve model, then to analyze and applicate the learning curve. METHODS: Twelve graduate students participating in standardized dental resident training were selected to prepare the resin maxillary central incisors on phantom head simulators for all ceramic crowns 4 times. The results of preparation were evaluated by 3 prosthetic experts with at least 10 years' experience focusing on the reduction, contour, taper, shoulder, finish line, margin placement, adjacent tooth injury, and preparation time for tooth preparation. The learning rate of tooth preparation was calculated by scores of tooth preparation of 4 times. The learning curve of tooth preparation was predicted based on the modified Wright learning curve model. According to the criteria of standardized training skill examinations for dental residents in Beijing, 80 was taken as the qualified standard score. The minimum training times for tooth preparation to satisfy the qualified standard score (80) was calculated, to analyze the characteristics of learning curve and evaluate the effectiveness of tooth preparation. RESULTS: The scores of 4 tooth preparation were 64.03±7.80, 71.40±6.13, 74.33±5.96, and 75.98±4.52, respectively. The learning rate was (106±4)%, which showed the learning curve an upward trend. There were no significant differences between the qualified standard score and the predicted scores of tooth preparation from the 5^th preparation to the 13^th preparation (P > 0.05). The predicted score of the 14^th preparation was higher than the qualified standard score (P < 0.05). CONCLUSION The trend of the learning curve of tooth preparation for all ceramic crowns of maxillary central incisors on phantom head simulators for graduate students participating in standardized dental resident training is upward, which predicts the minimum training times higher than the qualified standard score is 14 times.
Humans ; Tooth Preparation, Prosthodontic/methods* ; Incisor ; Learning Curve ; Crowns ; Tooth Preparation ; Ceramics ; Dental Porcelain ; Dental Prosthesis Design

Objective: To explore the incidence and risk factors of cardiovascular events in hematological neoplasms patients treated with anthracyclines in the real world. Methods: A total of 408 patients with lymphoma and leukemia, who were treated with anthracyclines during hospitalization in the First Affiliated Hospital of Dalian Medical University from January 1, 2018 to July 31, 2021, were included in this retrospective study. Patients were divided into cardiovascular event group (n=74) and non-cardiovascular event group (n=334). The primary endpoint was cardiovascular events (arrhythmia, heart failure, acute myocardial infarction etc.) after anthracyclines therapy. The secondary endpoint was all-cause mortality, cardiovascular-cause death, discontinued chemotherapy due to cardiovascular events. Multivariate regression analysis was used to investigate the risk factors of cardiovascular events. Kaplan-Meier was performed to calculate the incidence of all-cause mortality. Results: The mean age was (55.6±14.9) years, and there were 227 male patients (55.6%) in this cohort. The median follow-up time was 45 months. During follow-up, cardiovascular adverse events occurred in 74 patients (18.1%), including 45 heart failure (38 were heart failure with preserved ejection fraction), 30 arrhythmia, 4 acute myocardial infarction and 2 myocarditis/pericarditis. Multivariate regression analysis showed age (OR=1.024, 95%CI 1.003-1.045, P=0.027) and history of hypertension over 10 years (OR=2.328, 95%CI 1.055-5.134, P=0.036) were independent risk factors for the cardiovascular events. Kaplan-Meier survival curve showed mortality was significantly higher in cardiovascular event group than in non-cardiovascular event group (47.3% vs. 26.6%, P=0.001). In the cardiovascular event group, chemotherapy was discontinued in 9 cases (12.2%) due to cardiovascular events and cardiovascular death occurred in 7 cases (9.5%). Conclusions: Although heart failure is the main cardiovascular event in lymphoma and leukemia patients post anthracyclines therapy, other cardiovascular events especially arrhythmias are also common. The presence of cardiovascular events is associated with higher risk of all-cause mortality in these patients. Age and long-term hypertension are independent risk factors for cardiovascular events in lymphoma and leukemia patients after anthracyclines treatment.
Humans ; Male ; Adult ; Middle Aged ; Aged ; Child ; Anthracyclines/adverse effects* ; Retrospective Studies ; Risk Factors ; Heart Failure/drug therapy* ; Myocardial Infarction/complications* ; Hematologic Neoplasms/complications* ; Arrhythmias, Cardiac/complications* ; Leukemia/complications* ; Hypertension/complications*

OBJECTIVE: To identify the role of Tribbles pseudokinase 3 (TRIB3) during the process of adipogenic differentiation of human adipose-derived mesenchymal stem cells (hASCs), and to provide a new target and a novel idea for the application of hASCs in adipose tissue engineering and soft tissue regeneration. METHODS: TRIB3-knockdown hASCs (shTRIB3) and TRIB3-overexpression hASCs (TRIB3-over) were established using lentivirus transfection technique. The transfection effect was estimated by the visible presence of green fluorescence as the expression of green fluorescent protein (GFP) in the transfected hASCs. The lentiviral transfection efficiency was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. After adipogenic induction, Oil Red staining and quantification, as well as qRT-PCR about several specific adipogenic markers were used to evaluate the adipogenic differentiation ability of hASCs. RESULTS: In TRIB3-knockdown hASCs, the TRIB3 mRNA expression level decreased by about 84.3% compared with the control group (P<0.01), and the TRIB3 protein level also showed obvious reduction. Oppositely, in TRIB3-overexpression hASCs, the TRIB3 mRNA expression level increased by approximately 160% compared with the control group (P<0.01), and the TRIB3 protein level also showed a significant increase. These results indicated a successful construction of TRIB3-knockdown hASCs and TRIB3-overexpression hASCs. The Oil Red staining results showed that the down-regulation of TRIB3 significantly promoted lipid droplets formation in hASCs, consistent with Oil Red quantification. On the other hand, the up-regulation of TRIB3 suppressed lipid droplets formation in hASCs, consistent with Oil Red quantification. After adipogenic induction, adipogenesis-related genes, including peroxisome proliferator-activated receptor γ (PPARγ), cluster of differentiation 36 (CD36) and CCAAT/enhancer binding protein α (C/EBPα), were increased significantly in TRIB3-knockdown hASCs compared with the control group (P<0.01). Oppositely, PPARγ, CD36 and lipoprotein lipase (LPL) were significantly decreased in TRIB3-overexpression hASCs compared with the control group (P<0.01). CONCLUSION TRIB3 inhibited the adipogenic differentiation of hASCs. Knockdown of TRIB3 promoted the ability of adipogenesis of hASCs, while overexpression of TRIB3 inhibited the adipogenic differentiation of hASCs. Considering the important role of PPARγ in the adipogenis process, the molecular mechanism of the regulatory function of TRIB3 may be related with PPARγ signal pathway.
Adipogenesis ; Adipose Tissue ; Cells, Cultured ; Humans ; Mesenchymal Stem Cells

PURPOSE: Conditional survival (CS) provides important information on survival for a period of time after diagnosis. Currently, information on CS patterns of patients with nasopharyngeal carcinoma (NPC) is lacking. We aimed to analyze survival rate over time and estimate CS for NPC patients using a national population-based registry. MATERIALS AND METHODS: Patients diagnosed with NPC between 1973 and 2007 with at least 5-year follow-up were identified from the Surveillance Epidemiology End Results registry. Traditional survival rates and crude CS estimateswere calculated using Kaplan-Meier analysis. Risk-adjusted survival curves were plotted from the proportional hazards model using the correct group prognosis method. RESULTS: For 7,713 patients analyzed, adjusted baseline 5-year overall survival improved significantly from 36.0% in patients diagnosed in 1973-1979, 41.7% in 1980-1989, 46.6% in 1990-1999, to 54.7% in 2000-2007 (p < 0.01). CS analysis demonstrated that for every additional year survived, adjusted probability of surviving the next 5 years increased from 66.7% (localized), 54.0% (regional), and 35.3% (distant) at the time of diagnosis, to 83.7% (localized), 75.0% (regional), and 62.2% (distant) for patients who had survived 5 years. Adjusted 5-year CS differed among age, sex, tumor histology, ethnicity, and stage subgroups initially, but converged with time. CONCLUSION: Treatment outcomes of NPC patients have greatly improved over the decades. Increases in CS become more prominent in patients with distant disease than in those with localized or regional disease as patients survive longer. CS provides more dynamic prognostic information for patients who have survived a period of time after diagnosis.
Diagnosis ; Epidemiology* ; Follow-Up Studies ; Humans ; Kaplan-Meier Estimate ; Methods ; Nasopharyngeal Neoplasms ; Prognosis ; Proportional Hazards Models ; SEER Program ; Survival Rate

In this study, solid dispersion system of magnolol in croscarmellose sodium was prepared by using the solvent evaporation method, in order to increase the drug dissolution. And its dissolution behavior, stability and physical characteristics were studied. The solid dispersion was prepared with magnolol and croscarmellose sodium, with the proportion of 1∶5, the in vitro dissolution of magnolol solid dispersion was up to 80.66% at 120 min, which was 6.9 times of magnolol. The results of DSC (differential scanning calorimetry), IR (infra-red) spectrum and SEM (scanning electron microscopy) showed that magnolol existed in solid dispersion in an amorphous form. After an accelerated stability test for six months, the drug dissolution and content in magnolol solid dispersion showed no significant change. So the solid dispersion prepared with croscarmellose sodium as the carrier can remarkably improve the stability and dissolution of magnolol.

Clinical breakpoints are used in phaseⅡorⅢclinical trials to categorize microorganisms if susceptibility to new tested antibacterial agents that means the patient infected by the pathogen will be enrolled the study or not.The role of this consensus is to define procedure and required data to setting breakpoints and how to revaluate it in clinical trials.

OBJECTIVETo assese the healing of stoma after magnetic anastomosis for the reconstruction of biliary-enteric continuity under severe inflammation.

METHODSAcute bile duct injury was constructed as a bile peritonitis model in mongrel dogs (n=32). Magnetic anastomosis (group A, n=16) and traditional suture anastomosis (group B, n=16) were performed to reconstruct the biliary-enteric continuity in one stage. Half of the dogs in each group were euthanized on the 30th postoperative day, and the other half on the 90th postoperative day to harvest the stoma region. The healing conditions of the stoma after the 2 anastomotic approaches were observed with naked eyes, under light microscope and scanning electron microscope.

RESULTSThe stoma leakage rate (50% versus 0% on the 30th postoperative day, 37.5% versus 12.5% on the 90th postoperative day, both P<0.05) and stenosis degree (13.9%±0.3% versus 7.1%±0.3% on the 30th postoperative day, 17.2%±0.4% versus 9.4%±0.4% on the 90th postoperative day, both P<0.01) were significantly higher in group B than in group A. Compared with traditional manual anastomoses, the histological analysis under light and electron microscope showed a more continuous stoma with more regular epithelium proliferation and collagen arrangement, less inflammation in group A.

CONCLUSIONSMagnetic anastomosis stent ensures better healing of the stoma even under the circumstance of severe inflammation.

Anastomosis, Surgical ; Animals ; Bile Ducts ; surgery ; Disease Models, Animal ; Dogs ; Female ; Intestines ; surgery ; Magnetics ; Male ; Microscopy, Electron, Scanning ; Peritonitis ; surgery ; Surgical Stomas ; Wound Healing

AIM: To improve the absorption and bioavailability of baicalin using a nanocrystal (or nanosuspension) drug delivery system. METHODS: A tandem, ultrasonic-homogenization-fluid bed drying technology was applied to prepare baicalin-nanocrystal dried powders, and the physicochemical properties of baicalin-nanocrystals were characterized by scanning electron microscopy, photon correlation spectroscopy, powder X-ray diffraction, physical stability, and solubility experiments. Furthermore, in situ intestine single-pass perfusion experiments and pharmacokinetics in rats were performed to make a comparison between the microcrystals of baicalin and pure baicalin in their absorption properties and bioavailability in vivo. RESULTS: The mean particle size of baicalin-nanocrystals was 236 nm, with a polydispersity index of 0.173, and a zeta potential value of -34.8 mV, which provided a guarantee for the stability of the reconstituted nanosuspension. X-Ray diffraction results indicated that the crystallinity of baicalin was decreased through the ultrasonic-homogenization process. Physical stability experiments showed that the prepared baicalin-nanocrystals were sufficiently stable. It was shown that the solubility of baicalin in the form of nanocrystals, at 495 μg·mL(-1), was much higher than the baicalin-microcrystals and the physical mixture (135 and 86.4 μg·mL(-1), respectively). In situ intestine perfusion experiments demonstrated a clear advantage in the dissolution and absorption characteristics for baicalin-nanocrystals compared to the other formulations. In addition, after oral administration to rats, the particle size decrease from the micron to nanometer range exhibited much higher in vivo bioavailability (with the AUC(0-t) value of 206.96 ± 21.23 and 127.95 ± 14.41 mg·L(-1)·h(-1), respectively). CONCLUSION The nanocrystal drug delivery system using an ultrasonic-homogenization-fluid bed drying process is able to improve the absorption and in vivo bioavailability of baicalin, compared with pure baicalin coarse powder and micronized baicalin.
Animals ; Biological Availability ; Chemistry, Pharmaceutical ; methods ; Flavonoids ; chemistry ; pharmacokinetics ; Male ; Nanoparticles ; chemistry ; Particle Size ; Rats ; Rats, Wistar ; Solubility ; Ultrasonics ; X-Ray Diffraction

Objective To assese the healing of stoma after magnetic anastomosis for the reconstruction of biliary-enteric continuity under severe inflammation.
Methods Acute bile duct injury was constructed as a bile peritonitis model in mongrel dogs (n=32). Magnetic anastomosis (group A, n=16) and traditional suture anastomosis (group B, n=16) were performed to reconstruct the biliary-enteric continuity in one stage. Half of the dogs in each group were euthanized on the 30th postoperative day, and the other half on the 90th postoperative day to harvest the stoma region. The healing conditions of the stoma after the 2 anastomotic approaches were observed with naked eyes, under light microscope and scanning electron microscope.
Results The stoma leakage rate (50%versus 0%on the 30th postoperative day, 37.5%versus 12.5%on the 90th postoperative day, both P<0.05) and stenosis degree (13.9%±0.3%versus 7.1%±0.3%on the 30th postoperative day, 17.2%±0.4%versus 9.4%±0.4%on the 90th postoperative day, both P<0.01) were significantly higher in group B than in group A. Compared with traditional manual anastomoses, the histological analysis under light and electron microscope showed a more continuous stoma with more regular epithelium proliferation and collagen arrangement, less inflammation in group A.
Conclusions Magnetic anastomosis stent ensures better healing of the stoma even under the circumstance of severe inflammation.

OBJECTIVETo explore the safety and feasibility of biodegradable magnesium alloy stapler based on the result of animal experimental study for gastrointestinal anastomosis.

METHODSSixteen beagle dogs were equally and randomly divided into experimental (magnesium alloy) group and control (titanium alloy) group. A gastrojejunal and a colonic anastomosis were performed in each beagle dog. The anastomosis time, postoperative complications, body weight, blasting pressure of anastomosis and serum glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, creatinine, blood urea nitrogen, and serum magnesium were compared between the two groups. The healing of anastomosis and degradation of magnesium alloy were observed. The histopathological features of heart, liver, spleen and kidney were examined in the two groups.

RESULTSThere were no significant differences in anastomosis time, body weight, postoperative complications, anastomotic bursting pressure between the two groups. The anastomosis was healed well, and no dramatic inflammatory cell infiltration was observed. Magnesium alloy could be degraded completely in the animal body within 90 days. There were no significant differences in serum glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, creatinine, blood urea nitrogen and serum magnesium between the two groups. Histopathological examination showed that the degradation of magnesium alloy did not harm the important organs (liver, kidney, heart, brain and spleen).

CONCLUSIONSMagnesium alloy stapler is safe and feasible for gastrointestinal anastomosis in beagle dogs. The degradation of magnesium alloy does not harm the healing of anastomosis and other important organs. Magnesium alloy stapler may be a candidate of biodegradable and safe material of stapler for gastrointestinal anastomosis in human.

Absorbable Implants ; Alloys ; Animals ; Dogs ; Female ; Gastroenterostomy ; instrumentation ; Magnesium ; Male ; Sutures ; Titanium