1.Effect of erosion on strength of dental infiltrated Al2O3 ceramics.
Fang XIONG ; Haiyang A YU ; Yunmao LIAO ; Zhimin ZHU ; Zhongrong ZHOU ; Minhao ZHU
Journal of Biomedical Engineering 2005;22(6):1189-1199
The objective of the research is to investigate the elements of routine sandblast technique on the evolution of bending strength of dental infiltrated Al2O3 ceramics and the underlying erosion mechanism. The plane specimens of an infiltrated ceramic were manufactured, polished and then tested under the modified pen-like sandblasting apparatus (90 degrees erosive angle and 10 mm sandblasting distance), with different grit sizes, working pressure and disposing time. Half of samples were selected randomly and sintered subsequently with Vitadur alpha veneering porcelain. Before and after sintering, the three-point-bending strengths was measured, and the surfaces of dental porcelain were observed with SEM and LCSM. The bending strength of ceramics decreased significantly after sandblast as compared with that of empty control group. After the procedure of sintering the veneering porcelain, the descending evolution of bending strength slowed down. Under the present manufacturing conditions, grit size effect is prominent among those correlative elements of sand grit size, working pressure and disposing time. And fatigue cracking characterizes the mechanism of erosion of dental infiltrated Al2O3 ceramics.
Aluminum Oxide
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chemistry
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Dental Materials
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chemistry
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Dental Stress Analysis
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Humans
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Materials Testing
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Metal Ceramic Alloys
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chemistry
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Shear Strength
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Stress, Mechanical
2.Prognostic Value of the Evolution of HER2-Low Expression after Neoadjuvant Chemotherapy
Youzhao MA ; Mingda ZHU ; Jingyang ZHANG ; Minhao LV ; Xiuchun CHEN ; Zhenzhen LIU
Cancer Research and Treatment 2023;55(4):1210-1221
Purpose:
Patients with human epidermal growth factor receptor 2 (HER2)–low advanced breast cancer can benefit from trastuzumab deruxtecan. Given the unclear prognostic characteristics of HER2-low breast cancer, we investigated the prognostic characteristics of HER2-low expression from primary tumor to residual disease after neoadjuvant chemotherapy (NACT).
Materials and Methods:
The data of HER2-negative patients receiving NACT at our center were collected. Pathological complete response (pCR) rate were compared between HER2-0 and HER2-low patients. The evolution of HER2 expression from primary tumor to residual disease and its impact on disease-free survival (DFS) were examined.
Results:
Of the 690 patients, 494 patients had HER2-low status, of which 72.3% were hormone receptor (HR)–positive (p < 0.001). The pCR rates of HER2-low and HER2-0 patients (14.2% vs. 23.0%) showed no difference in multivariate analysis regardless of HR status. No association was observed between DFS and HER2 status. Of the 564 non-pCR patients, 57 (10.1%) changed to HER2-positive, and 64 of the 150 patients (42.7%) with HER2-0 tumors changed to HER2-low. HER2-low (p=0.004) and HR-positive (p=0.010) tumors before NACT were prone to HER2 gain. HER2 gain patients had a better DFS compared with HER2-negative maintained patients (87.9% vs. 79.5%, p=0.048), and the DFS of targeted therapy group was better than that of no targeted therapy group (92.4% vs. 66.7%, p=0.016).
Conclusion
Although HER2-low did not affect the pCR rate and DFS, significant evolution of HER2-low expression after NACT creates opportunities for targeted therapy including trastuzumab.
3.Lateral rectus abdominis approach combined with presacral decompression for old Denis type II sacral fractures complicated with upper sacral plexus injury
Minhao WU ; Keke XU ; Zimeng CHEN ; Huowen LIU ; Yuanlong XIE ; Feifei YAN ; Ansong PING ; Zhouming DENG ; Xiaobin ZHU ; Yongjian QI ; Jun LEI ; Lin CAI
Chinese Journal of Trauma 2020;36(5):421-427
Objective:To investigate the clinical effect of lateral rectus abdominis approach combined with presacral decompression for surgical treatment of old Denis type II sacral fractures complicated with upper sacral plexus injury.Methods:A retrospective case series study was performed on the clinical data of 9 patients with old Denis type II sacral fractures complicated with upper sacral plexus injury (L 4-S 1) admitted to Zhongnan Hospital of Wuhan University from June 2010 to December 2016. There were 6 males and 3 females, aged (33.1±7.5)years (range, 15-58 years). Embolization of internal iliac artery and preimplantation of abdominal aortic balloon were performed 2 hours before operation under the guidance of digital subtraction angiography (DSA). Surgery was performed using a single lateral rectus abdominis approach combined with presacral decompression. The operation time, intraoperative blood loss and full weight-bearing time were recorded. The visual analogue scale (VAS) and European QOL Five Dimensional health scale (EQ-5D) were compared before and after operation. The Gibbons' impairment scale was used to assess neurological function. X-ray and CT scan were used to observe internal fixation and fracture healing. The complications during and after operation were recorded. Results:The patients were followed up for 24-52 months [(35.2±5.2)months]. The operation time was (2.9±0.6)hours. The intraoperative bleeding was (573±138)ml, and the full weight-bearing time was (11.6±1.2)weeks. X-ray and CT scan showed bone healing in all patients at the latest follow-up. The VAS and EQ-5D scale improved from preoperative (7.8±0.6)points and (0.34±0.07)points to the final follow-up of (0.8±0.3)points and (0.81±0.05)points ( P<0.05). According to Gibbons classification, 8 patients were grade I and 1 patient was grade II one year after operation ( P<0.01). Namely, the radiation pain of lower extremities was significantly improved in all patients, among which 8 patients showed pain disappeared and completely returned to normal and 1 patient showed residual numbness and hypoesthesia of the affected limbs. No major complications (eg, iatrogenic lumbosacral plexus injury, vital blood vessels or pelvic organs injury) occurred during the operation. During the follow-up period, only one patient developed traumatic hip arthritis and underwent total hip arthroplasty 6 months after operation. Fractures of the remaining patients were healed well without complications like infection, pressure ulcer or implant failure. Conclusions:For old Denis type II sacral fractures complicated with upper sacral plexus injury, lateral rectus abdominis approach combined with presacral decompression can fully decompress the upper sacral plexus nerve, relieve pain, and promote functional rehabilitation, with low incidence of complications. It is an alternative surgical method for the treatment of old Denis type II sacral fractures complicated with upper sacral plexus injury.
4.Meta-analysis of β-blockers for the primary prevention of liver cirrhosis with clinically significant portal hypertension with no or small esophageal varices
Xin SU ; Wenjie LI ; Zhe CHEN ; Qibiao WU ; Minhao YIN ; Xu HAN ; Danping ZHANG ; Xiqiao ZHOU ; Hong ZHU
Chinese Journal of Hepatology 2022;30(11):1237-1245
Objective:To explore whether NSBB is suitable for the primary prevention of liver cirrhosis accompanied by CSPH with no or small esophageal varices.Methods:Relevant literatures were retrieved from Cochrane library, PubMed, EMBASE, SinoMed, CNKI and Wanfang databases until December 12, 2020. All randomized controlled trials (RCTs) on NSBB use for primary prevention of cirrhosis accompanied by CSPH with no or small esophageal varices were collected. The literature was strictly screened according to the established inclusion and exclusion criteria, odds ratio (OR), and 95% confidence interval (CI) combined effect size. The development of esophageal varices and the initial upper gastrointestinal bleeding were the primary outcome measures. Death (with a maximum average follow-up of about five years) and adverse events (adverse drug reactions, etc.) were the secondary outcome measures.Results:A total of 9 RCTs with 1396 cases were included. Meta-analysis results showed that, compared with placebo, NSBB significantly reduced the incidence of liver cirrhosis accompanied by CSPH with no or small esophageal varices to large esophageal varices progression ( OR=0.51, 95% CI: 0.29-0.89, P=0.02), and mortality (with maximum average follow-up of about five years) ( OR=0.64, 95% CI: 0.44-0.92, P=0.02); however, there was no statistically significant difference in the initial upper gastrointestinal bleeding rate between the two groups ( OR=0.82, 95% CI: 0.44-1.52, P=0.53). Adverse event incidence was greater in the NSBB than the placebo group ( OR=1.74, 95% CI: 1.27-2.37, P=0.0005). Conclusions:NSBB use cannot reduce the initial upper gastrointestinal bleeding rate or adverse event incidence in patients with liver cirrhosis accompanied by CSPH with no or small esophageal varices, but it can delay the progression of gastroesophageal varices and reduce patient mortality.
5.Site-specific labelling and biological evaluation of PD-L1 targeted single-domain antibody
Yinfei CHEN ; Panpan CHEN ; Shiyu ZHU ; Beibei LIANG ; Minhao XIE ; Jianguo LIN ; Ling QIU
Chinese Journal of Nuclear Medicine and Molecular Imaging 2022;42(12):744-750
Objective:To synthesize a novel site-specifically labelled probe 68Ga-1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)-Cys-Asp-Val (CDV)-Nb109 and explore its potential for detection of the programmed cell death ligand 1 (PD-L1) expression level in different tumors. Methods:Firstly, CDV was inserted into the tail of the sequence of Nb109 by genetic engineering. Then the precursor DOTA-CDV-Nb109 was prepared by mixing the maleimide-DOTA and the single-domain antibody CDV-Nb109 (amount of substance ratio 1∶1) via the maleimide-cysteine site-specific coupling strategy. Subsequently, the DOTA-CDV-Nb109 was labeled with 68Ga and purified by PD-10 column. Human melanoma A375, human PD-L1 transfected melanoma A375-hPD-L1 and human glioma U87 tumor-bearing mice models were established, and the diagnostic value of 68Ga-DOTA-CDV-Nb109 was evaluated by stability assay, cellular uptake, and microPET imaging. One-way analysis of variance and the least significant difference t test were used to analyze the data. Results:The probe 68Ga-DOTA-CDV-Nb109 was obtained with the radiochemical yield of (69.79±4.69)%, radiochemical purity more than 97%, and molar activity of (12.85±1.51) GBq/μmol. 68Ga-DOTA-CDV-Nb109 had strong binding affinity for A375-hPD-L1 with the dissociation constant ( Kd) of (66.43±17.89) nmol/L. The uptake of 68Ga-DOTA-CDV-Nb109 in A375-hPD-L1 and U87 cells were (3.17±0.15) percentage of the added radioactivity dose (%AD) and (2.08±0.03) %AD respectively, which were significantly higher than that in A375 cells ((1.21±0.14) %AD; F=82.87, t values: 15.23, 9.98, P values: <0.001, 0.003). The tumor uptake of the probe in A375-hPD-L1 ((5.21±0.35) percentage of injected dose per ml (%ID/ml)) and U87 tumor-bearing mice ((3.44±0.69) %ID/ml) were significantly higher than that in A375 tumor-bearing mice ((2.17±0.36) %ID/ml; F=249.72, t values: 35.70, 3.43, both P<0.001). Conclusion:The site-specifically labelled probe 68Ga-DOTA-CDV-Nb109, which can non-invasively and dynamically monitor the change of PD-L1 expression level in different tumors and help screen patients who can benefit from PD-L1 immune checkpoint blocking therapy, is successfully synthesized with high radiochemical purity.
6.Development of a radiolabeled site-specific single-domain antibody positron emission tomography probe for monitoring PD-L1 expression in cancer
Yinfei CHEN ; Shiyu ZHU ; Jiayu FU ; Jianguo LIN ; Yan SUN ; Gaochao LV ; Minhao XIE ; Tao XU ; Ling QIU
Journal of Pharmaceutical Analysis 2022;12(6):869-878
Despite advances in immunotherapy for the treatment of cancers,not all patients can benefit from programmed cell death ligand 1(PD-L1)immune checkpoint blockade therapy.Anti-PD-L1 therapeutic effects reportedly correlate with the PD-L1 expression level;hence,accurate detection of PD-L1 expression can guide immunotherapy to achieve better therapeutic effects.Therefore,based on the high affinity antibody Nb109,a new site-specifically radiolabeled tracer,68Ga-NODA-cysteine,aspartic acid,and valine(CDV)-Nb109,was designed and synthesized to accurately monitor PD-L1 expression.The tracer 68Ga-NODA-CDV-Nb109 was obtained using a site-specific conjugation strategy with a radiochemical yield of about 95%and radiochemical purity of 97%.It showed high affinity for PD-L1 with a dissociation constant of 12.34±1.65 nM.Both the cell uptake assay and positron emission tomography(PET)imaging revealed higher tracer uptake in PD-L1-positive A375-hPD-L1 and U87 tumor cells than in PD-L1-negative A375 tumor cells.Meanwhile,dynamic PET imaging of a NC1-H1299 xenograft indicated that doxorubicin could upregulate PD-L1 expression,allowing timely interventional immunotherapy.In conclusion,this tracer could sensitively and dynamically monitor changes in PD-L1 expression levels in different cancers and help screen patients who can benefit from anti-PD-L1 immunotherapy.
7. High Expression of GADD45B Induced by Acid and Bile Acid is A Potential Prognostic Marker for Barrett's Esophagus-associated Adenocarcinoma
Xin SU ; Danping ZHANG ; Zhe CHEN ; Xu HAN ; Peichen XIA ; Minhao YIN ; Wenjie LI ; Shuo LI ; Guoqin ZHU ; Hong ZHU
Chinese Journal of Gastroenterology 2021;26(11):647-655
Background: Esophageal mucosal injury induced by gastroesophageal reflux is a key link to the development of Barrett's esophagus-associated adenocarcinoma. However, the molecular mechanism is still not elucidated. Aims: To investigate the role of differentially expressed genes (DEGs) after stimulating esophageal cells with acid and bile acid in the development of esophageal adenocarcinoma (EAC). Methods: The DEGs were obtained through bioinformatics methods after stimulating esophageal cells with low pH and deoxycholic acid, and GO, KEGG enrichment analysis were performed. Protein-protein interaction (PPI) network was performed to screen the hub genes, and their relationships with prognosis and tumor stage of EAC patients were analyzed. The role of co-expressed genes of GADD45B in EAC was also analyzed. Results: Thirty-one overlapping DEGs were obtained after stimulating esophageal cells with low pH and deoxycholic acid, which mainly enriched in the cytokine-cytokine receptor interaction, transcription factors activity, and regulation of cell proliferation and apoptotic process. High expression of GADD45B was correlated with the survival prognosis and tumor stage of EAC patients. GADD45B and its co-expressed genes were involved in the production of tumor necrosis factor. Conclusions: The high expression of GADD45B induced by acid and bile acid is correlated with the prognosis and tumor stage of EAC patients, and is a potential diagnosis and treatment target for Barrett's esophagus-associated adenocarcinoma.