Efficacy of CLAE Chemotherapy Regimen Followed by Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Relapsed/Refractory Acute Leukemia / 中国实验血液学杂志

OBJECTIVE@#To observe the efficacy and safety of CLAE intensive chemotherapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with relapsed/refractory acute leukemia (R/R AL).@*METHODS@#CLAE regimen [cladribine 5 mg/(m2·d), d 1-5; cytarabine 1.5 g/(m2·d), d 1-5; etoposide 100 mg/(m2·d), d 3-5] followed by allo-HSCT was used to treat 3 R/R AL patients. The patients received CLAE chemotherapy in relapsed or refractory status and underwent bone marrow puncture to judge myelodysplastic state. After an interval of 3 to 5 days, followed by preconditioning regimen for allo-HSCT [fludarabine 30 mg/(m2·d), d -7 to d -3; busulfan 0.8 mg/kg q6h, d -6 to d -3 or d -5 to d -2. If the bone marrow hyperplasia was not active and the blasts were less than 10%, busulfan should be used for 3 days. If the bone marrow hyperplasia was active and the blasts were more than 10%, busulfan should be used for 4 days]. Cyclosporin A, mycophenolate mofetil and short-term methotrexate were used for graft-versus-host disease (GVHD) prevention. After transplantation, the status of minimal residual disease (MRD) and bone marrow chimerism were regularly monitored in all 3 patients, and demethylation drugs or dasatinib were used to prevent recurrence 3 months after transplantation.@*RESULTS@#2 patients with t(11;19) translocation and relapse/refractory acute myeloid leukemia recurred within 6 months after induction of remission, and received intensive chemotherapy with CLAE regimen followed by haploidentical allo-HSCT and unrelated donor allo-HSCT, respectively. The two patients both relapsed 6 months after transplantation, then achieved complete remission by donor lymphocyte infusion, interferon, interleukin-2 and other methods, and disease-free survival was 2 years after transplantation. The other patient was chronic myelogenous leukemia who developed acute lymphoblastic leukemia during oral administration of tyrosine kinase inhibitor, accompanied by T315I and E255K mutations in ABL1 kinase region and additional chromosomal abnormalities. After morphological remission by induction chemotherapy, central nervous system leukemia was complicated. Intensive chemotherapy with CLAE regimen followed by sibling allo-HSCT was performed in the positive state of MRD. The patient relapsed 3 months after transplantation, and achieved remission after chimeric antigen receptor T-cell (CAR-T) therapy, however, he died 5 months after transplantation because of severe cytokine release syndrome (CRS) and GVHD.@*CONCLUSION@#CLAE regimen followed by allo-HSCT may be an effective salvage treatment option for R/R AL patients to prolong the overall survival.

Analysis of prognostic factors of extranodal NK/T-cell lymphoma treated with pegaspargase/L-asparaginase: a multicenter retrospective study / 中华血液学杂志

Objective: To explore the prognostic factors of extracellular NK/T cell lymphoma (ENKTL) treated with pegaspargase/L-asparaginase. Methods: The clinical data of 656 ENKTL patients diagnosed at 11 medical centers in the Huaihai Lymphoma Working Group from March 2014 to April 2021 were retrospectively analyzed. The patients were randomly divided into two groups: a training set (460 cases) and a validation set (196 cases) at 7∶3, and the prognostic factors of the patients were analyzed. A prognostic scoring system was established, and the predictive performance of different models was compared. Results: Patients' median age was 46 (34, 57) years, with 456 males (69.5% ) and 561 nasal involvement (85.5% ). 203 patients (30.9% ) received a chemotherapy regimen based on L-asparaginase combined with anthracyclines, and the 5-year overall survival rate of patients treated with P-GEMOX regimen (pegaspargase+gemcitabine+oxaliplatin) was better than those treated with SMILE regimen (methotrexate+dexamethasone+cyclophosphamide+L-asparaginase+etoposide) (85.9% vs 63.8% ; P=0.004). The results of multivariate analysis showed that gender, CA stage, the Eastern Cooperative Oncology Group performance status (ECOG PS) score, HGB, and EB virus DNA were independent influencing factors for the prognosis of ENKTL patients (P<0.05). In this study, the predictive performance of the prognostic factors is superior to the international prognostic index, Korean prognostic index, and prognostic index of natural killer lymphoma. Conclusion: Gender, CA stage, ECOG PS score, HGB, and EB virus DNA are prognostic factors for ENKTL patients treated with pegaspargase/L-asparaginase.

Effect of CXCR4 on the Treatment Response and Prognosis of Carfilzomib in Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To explore the effect of CXCR4 on the treatment response and prognosis of Carfilzomib (CFZ) in multiple myeloma.@*METHODS@#Dataset GSE69078 based on microarray data from two CFZ-resistant MM cell lines and their corresponding parental cell lines (KMS11-KMS11/CFZ and KMS34-KMS34/CFZ) were downloaded from Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified, and Protein-protein interaction (PPI) network was established to identify the key genes involved in CFZ resistance acquisition. Finally, the prognostic roles of the CFZ risistance key genes in MM using MMRF-CoMMpass data study was verified.@*RESULTS@#44 up-regulated and 46 down-regulated DEGs were identified. Top 10 hub genes (CCND1, CXCR4, HGF, PECAM1, ID1, HEY1, TCF4, HIST1H4J, HIST1H2BD and HIST1H2BH) were identified via Protein-protein interaction (PPI) network analysis. The CoMMpass data showed that high CXCR4 expression showed correlation to relative higher relapse and progress rates and the overall survival was significant decreased in high CXCR4 patients (P=0.013).@*CONCLUSION@#CXCR4 perhaps plays a crucial role in CFZ acquired resistance, which might help identifying potential CFZ-sensitive patients before treatment and providing a new therapeutic target in CFZ-resistant MM.

Efficacy of Micro-Transplantation Consolidation Therapy for Patients with Acute Myeloid Leukemia after Complete Remission / 中国实验血液学杂志

OBJECTIVE@#To investigate the efficacy and safety of micro-transplantation in acute myeloid leukemia (AML).@*METHODS@#The clinical data of 13 adult AML patients who received micro-transplantation as consolidation therapy from July 2014 to October 2019 was retrospectively analyzed, and the adverse reactions and efficacy of micro-transplantation were followed up.@*RESULTS@#Eight patients received micro-transpantation were still in complete remission, 5 patients relapsed after micro-transplantation, 1 of them received umbilical cord blood micro-transplantation after remission by reinduction, and all of the 13 patients have survived till now. The median overall survival time was 13 months, and the median relapse-free survival time was 12 months. All 13 patients developed grade 2-4 hematological adverse reactions. The median recovery time of neutrophils and platesets was 13 (11-15) and 15 (13-17) days, respectively. None of the 13 patients developed acute or chronic graft versus host disease. Twelve patients suffered from different infections, however, there were no serious organ function injury complications happened.@*CONCLUSION@#The micro-transplomtation of HLA-incompatible stem cells derived from peripheral blood or umbilical and blood is an effective regimen for the consolidation therapy of AML, especially for the patients suffered from low and moderate risk of AML or the aged AML patients.

Relationship between chronic diseases and cognitive function in elderly patients of high intellectuals / 上海预防医学

Objective To determine the relationship between chronic diseases and cognitive function in elderly patients, for the purpose of preventing and alleviating cognitive malfunction. Methods A total of 100 retired high intellectuals with age older than 65 years were enrolled.They were hospitalized in Zhongshan Hospital and were requested to complete a conventional questionnaire.Cognitive function was evaluated by Montreal Cognitive Assessment (MoCA) Scale.Their chronic diseases including hypertension, coronary artery disease, diabetes mellitus were recorded and compared among subjects with different cognitive function levels. Results Based on MoCA Scale, 34 cases were sorted as having normal cognitive function, 50 cases as mild cognitive impairment, and 16 cases as moderate cognitive impairment.Patients with moderate cognitive impairment showed a significantly higher percentage of hypertension (93.8%), coronary artery disease (75.0%), stroke (56.3%), diabetes mellitus (56.3%) while the patients with normal cognitive function exhibited relatively lower percentage of the above-mentioned diseases (61.8%, 41.2%, 17.6%, 20.6%, respectively, P < 0.05).However such difference was not observed for respiratory disease and neoplastic disease among patients with different cognitive conditions (P>0.05).In addition, cardiovascular and metabolic diseases were found to be important risk factors of mild-to-moderate cognitive impairment (P=0.002). Conclusion Prevention and treatment of cardiovascular and metabolic diseases could be imperative to alleviate the process of cognitive impairment.

Significance of Targeted Sequencing Assay for Patients with Suspected Myeloid Malignancies / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical significance of the targeted next-generation sequencing assay for patients with suspected myeloid malignancies.@*METHODS@#A total of 39 hematopenia patients with suspected myeloid malignamies in Department of Hematology of The Affiliated Huai'an No.1 People's Hospital of Nanjing Medical University from January 2018 to April 2019 were treated, 20 hot spot genes of myelodysplastic syndrome (MDS) were detected.@*RESULTS@#Regarding the diagnostic type, there were 7 cases of idiopathic cytopenia of undetermined significance (ICUS), 8 cases of clonal cytopenias of undetermined significance (CCUS) and 24 cases of myeloid myeloid malignancies which included 18 cases of MDS, 4 cases of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) and 2 cases of acute myeloid leukemia. Positive mutation was detected in 70.8% (17/24) of myeloid malignancy patients , and 72.7% (16/22) in MDS and MDS/MPN patients. The main mutation types were ASXL1, TET2 and RUNX1. Compared with gene negative group, there were no significant differences in sex, age (＜60 years old or ≥60 years old), proportion of bone marrow blast cells (＜5% or≥5%) and cytogenetics (good, medium and poor) (P＞0.05). Furthermore, all 8 CCUS patients showed positive mutation, and the incidence of double or multiple mutation in CCUS group was significantly lower than that of the MDS and MDS/MPN group (37.5% vs 54.5%) (P=0.002). The mutation types between the two groups were similar, and there was no significant difference in variant allele frequency (P＞0.05).@*CONCLUSION@#Our results suggest that there are high rates of double or multiple mutations in myeloid malignancies, especially in patients with MDS and MDS/MPN. Targeted sequencing assay can improve the diagnosis of myeloid malignancies, and guide clinical treatment.

Clinical Analysis of 66 Patients with Essential Thrombocytopenia / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical characteristics of essential thrombocytopenia (ET) patients with positive mutations including JAK2, CALR, MPL, or negative mutations.@*METHODS@#A total of 66 newly diagnosed ET cases from January 2016 to December 2018 in Department of Hematology, Huaian No.1 People's Hospital affiliated to Nanjing Medical University were analyzed. Statistical analysis data included the patient's sex, age, symptoms, thrombosis and embolism events, spleen omegaly, platelet count (Plt), leukocyte (WBC) count, hemoglobin (Hb), fibrinogen (FIB), thrombus elastic diagram (TEG), serum potassium, blood glucose (GLU), lactate dehydrogenase (LDH), JAK2, CALR and MPL mutations, treatment options, and efficacy.@*RESULTS@#All the patients were not MPL-positive, and divided in three groups: JAK2 mutation (46 cases, 69.7%), CALR mutation (9 cases, 13.6%) and gene negative mutation (11 cases, 16.7%) group. The average age of patients in the JAK2 mutation group was 63.2 years old, and significantly higher than that in the CALR mutation group (51.8 year) and gene negative group (50.2 year) (P＜0.05). Compared with the JAK2 mutation group and gene negative group, the CALR mutation group had lower WBC count (6.3×10/L vs 13.79×10/L) (P=0.003) (6.3×10/L vs 9.70×10/L) (P=0.009). Also the Hb level of patients in CALR mutation group was lower than the JAK2 mutation group (121.22 g/L vs 136.2 g/L) (P=0.036). However, there was higher tumor burden in the CALR mutation group, compared with the gene negative mutation group (300.11 U/L vs 227.4 U/L) (P=0. 033). There was no significant difference among the three groups, such as the Plt counts, serum potassium level, GLU level and FIB level (P＞0.05). In addition, thrombus and embolism appeared in 30.3% (20/66) cases. 18.2% (12/66) cases were complicated with hyperkalemia, which significantly correlated with Plt counts (r=0.518). TEG was performed in 34 patients, of which 41.2% (14/34) had abnormal TEG and 55.9% (19/34) were accompanied by Plt count ＞ 1 000 ×10/L, but there was no significant correlation between them (r=0.134). After routine clinical treatment, all the 66 cases achieved partial or complete hematological remission, but the disease usually repeated. Until now 4.5% (3/66) cases had been converted to myelofibrosis (MF) all with JAK2 mutation, but without advancing to acute myeloid leukemia.@*CONCLUSION@#ET patients with JAK2 mutation have higher incidence, moreover were in older age. However, the patients with CALR mutations display lower WBC count and Hb level, but higher tumor burden. In short, the multiple gene mutations of ET showed different clinical features closely relates with the prognosis, thus providing guidance for the clinical diagnosis and treatment.

Therapeutic Response and Prognosis of Adult Acute Myeloid Leukemia with Chromosome Karyotype Abnormalities / 中国实验血液学杂志

OBJECTIVE@#To investigate the efficacy and prognosis of acute myeloid leukemia (AML) patients with chromosome karyotype abnormalities.@*METHODS@#The clinical features and treatment responses of 91 patients with AML were collected and analyzed retrospectively. The efficacy and survival rate of the AML patients with normal and abnormal chromosome karyotype were compared.@*RESULTS@#Chromosome translocations and monosomal karyotypes were the main heterogeneity of AML. There was no significant difference in complete remission rate and overall response rate between the normal and abnormal karyotype groups, but the recurrence rate was higher in abnormal karyotype group. There was no significant difference in response of AML patients received the standard "3+7 regimen" and pre-excitation chemotherapy in the treatment of normal and abnormal karyotype groups. The relapse free survival time (RFS) was longer in the normal karyotype group, but there was no significant difference in overall survival time (OS).@*CONCLUSION@#The abnormal karyotype of AML is an independent prognostic factor, monosomal karyotype shows a poor prognosis, and the recurrence rate in AML patients with monosomal karyotype is higher.

Differential Regulation of Bruton's Tyrosine Kinase by the Ubiquitin Pathway / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the regulation of Bruton's tyrosine kinase (Btk) and to explore its possible mechanism.</p><p><b>METHODS</b>After treatment with the proteasome inhibitors and/or phorbol esters (PMA), the mRNA and protein expression level of Btk was detected by RT-PCR and Western blot, respectively. The ubiquitination level of Btk in B lymphoblastoid A20 cells was estimated after stimulation via the crosslinking of BCR with anti-IgM antibody. The cotransfection of COS-7 cell with Btk, ubiquitin and Cbl was performed, then the ubiquitination level of Btk was measured. The Btk ubiquitination level was detected after ectopic expression of ubiquitin transfected with the wild type or triple mutant of Ub (K29R, K48R, K63R) . Mono-ubiquitination of Btk was detected with antibodies preferentially against monovalent ubiquitin; in addition, the protein expression levels of chloroquine-treated stably transfected cells expressing Btk-GFP were detected by Western blot, and quantified with the strength of GFP fluorescence.</p><p><b>RESULTS</b>In the presence of proteasome-specific inhibitors and/or PMA, steady-state levels of Btk protein were reduced due to decrease of transcription. Posttranslational modification of Btk by ubiquitination was observed, which was related with the level of Btk expression and activation. The E3 ubiquitin ligase Cbl, which binds to Btk, was also found to ubiquitinate this kinase. Altogether, the data of this study strongly suggest that Btk is regulated by poly- and/or mono-ubiquitination events.</p><p><b>CONCLUSION</b>The Btk protein is dictated by its expression level through the ubiquitination pathway.</p>

Expression of Btk and NFκB in Acute Lymphoblastic Leukemia Cells and Its Significance / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To evaluate the role of Btk and NFκB in the incidence, development, prognosis and therapeutic efficacy for acute lymphoblastic leukemia(ALL) through detecting their expression in leukemia cells.</p><p><b>METHODS</b>Bone marrow samples from 51 ALL patients were collected, and the mononuclear cells were separated by Ficoll density gradient centrifugation. The expressions of Btk and NFκB at RNA and protein levels were detected by RT-PCR and Western blot respectively.</p><p><b>RESULTS</b>(1)At protein level, Btk and NFκB were expressed in all newly diagnosed 51 ALL patients, among them 38 patients had higher expression level of Btk, 34 patients had high NFκB expression level. The expression of Btk and NFκB was higher in the cells from newly diagnosed ALL patients than that in the cells from patients in CR(P<0.05), and the expression of Btk and NFκB was higher in relapsed ALL patients. (2)The expression of Btk and NFκB in the ALL patients was followed-up higher expression of Btk: among the 38 newly diagnosed B-ALL cases, 27 experienced CR (71%) and 12 of which achieved CR after one course chemotherapy (one course CR) (31%). Moreover, 16 out of the 27 CR patients relapsed after a short period (less than 6 months) (59%). On the contrary, among the 13 patients with low Btk expression, 11 achieved CR (84.6%) after one course and 1 relapsed (8 months after CR) (7.6%). A similar pattern of NFκB expression was observed.</p><p><b>CONCLUSION</b>Btk and NFκ B may play an important role in the incidence and progression of ALL, possibly serving as the potential therapeutic targets of ALL and the indexes for prognosis.</p>

Influence of Co-inhibiting mTORC2 and HSP90 on Proliferation Apoptosis of Multiple Myeloma Cells / 中国实验血液学杂志

<p><b>UNLABELLED</b>Objective：To explore the influence of co-inhibiting mTORC2 and HSP90 on the proliferation and apoptosis of multiple myeloma(MM) cell line U266.</p><p><b>METHODS</b>During culture, the human MM cell line U266 were treated with 20 nmol/L of rapamycin, 600 nmol/L 17-AAG, 20 nmol/L of rapamycin + 600 nmol/L 17-AGG and phosphate-buffered saline (PBS), then the growth inhibition rate, morphologic changes, apoptosis rate and the expression of caspase 3 and ATK protein in U266 cells were compared and analyzed.</p><p><b>RESULTS</b>The rapamycin and 17-AAG both could inhibit the growth of U266 cells, while the inhibitory effect of rapamycin in combination with 17-AAG on growth of U266 cells was significantly higher them that of rapamycin and 17-AAG alone and control (PBS); the apoptosis rate of U266 cells treated with rapamycin, 17-AAG and their combination was higher than that of control PBS groups, and the efficacy of 2 drug conbination was higher than that of control PBS group, and the efficacy of 2 drug combination was superior to single drug. The expression levels of caspase 3 and ATK in U266 cells treated with rapamycin, 17-AAG and their combination were higher and lower than those in control group respectively, and the efficacy of 2 drug combination was superior to signle drug. There were significant difference between them (P<0.05).</p><p><b>CONCLUSION</b>The co-inhibition of mTORC2 and HSP90 can suppress the proliferation and induce the apoptosis of MM cells.</p>

Study of Condylar Asymmetry in Angle Class III Malocclusion With Mandibular Deviation.

OBJECTIVE: Differences in the condylar between both sides in class III cases with mandibular deviated are important for the diagnosis, treatment, and retention in this kind of patient. To detect the subtle differences, we analyzed the size, shape, and bone density with three-dimensional reconstructed technology. METHODS: The symmetry group and the asymmetry group each with 20 cases were chosen according to some standards. The computed tomographic data obtained and three-dimensional model were built with SimPlant software. The distance and angle were measured in the three-dimensional model, and the bone density was measured with the SimPlant software. The differences between the separated side in each group and the difference between the 2 groups were analyzed. RESULTS: In the asymmetry group, some measurement projects of the bilateral condyles showed significant differences, such as the ramal height, condylar perpendicular height, the area of maximum cross section of condylar, condylar medialateral diameter, length of posterior slope, and angle of posterior slope. When the asymmetry group was compared with the symmetry group, the condyles of the asymmetry group showed more asymmetrical variations in morphology, such as the ramal height, the condylar perpendicular height, the area of maximum cross section of condylar, the medialateral diameter, the length of anterior slope, and angle of posterior slope. The bone mineral density of the condylar anterior and condylar medial point was higher in the nondeviated side, and the bone mineral density of the condylar posterior was higher in the deviated side, and no statistically significant difference was found in the symmetry group. CONCLUSIONS: In class III malocclusion with mandibular deviation patients, the three-dimensional morphology and bone density of condylar on the deviated side differ from the nondeviated side, which indicates the association between asymmetrical jaw function and joint remodeling.

Immunomodulatory activity of macromolecular polysaccharide isolated from Grifola frondosa / 中国天然药物

The present study was designed to evaluate the immune-modulating effects of the polysaccharide from Grifola frondosa (GFP) by using mouse peritoneal macrophage and cytoxan (CTX) induced immunosuppression models. Our results from the phagocytotic and mononuclear phagocytic system function assays showed that GFP-A (one component from GFP) stimulated the phagocytosis of the phagocytes. The splenocyte proliferation assay showed that GFP-A acted the effect combing ConA or LPS in splenocyte proliferation. The results showed that GFP-A increased indices of thymus and spleen, the levels of LDH and ACP in the spleen, the mRNA levels of IL-1β, IL-2, IL-6 and IFN-γ in splenocyte. And GFP-A also significantly increased the expression of CD4(+) and CD8(+) splenic T lymphocytes, which were suppressed by the CTX in peripheral blood. In conclusion, our results indicate that the GFP-A is involved in immunomodulatory effects leading to its modulatory effects on immunosuppression.

Influence of Fe₃O₄Magnetic Nanoparticles Combined with As2O3 and Adriamycin on Raji Cell Apoptosis and Autophagy / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of magnetic iron nanoparticles ( Fe₃O₄- MNP) in combination with arsenic trioxide and adriamycin on apoptosis and autophagy of Raji cells, a non-Hodgkin's lymphoma (NHL) cell line.</p><p><b>METHODS</b>The growth inhibition rate of Raji cells was analyzed by MTT assay, the cells apoptosis and intracellular concentration of ADM were determined by flow cytometry (FCM), the expression levels of apoptosis-related proteins such as BCL-2, NFκB, Survivin, BAX, P53, and Caspase-3, and related to autophagy-proteins, such as LC3, Beclin-1, and P62/SQSTM1 were detected by Western blot.</p><p><b>RESULTS</b>The growth inhibition of Raji cells in the group of ADM + As₂O₃were higher than that in the group of ADM or As₂O₃alone, however, lower than that in the group of Fe₃O₄- MNP combined with ADM and As₂O₃(ADM+As₂O₃+ MNP) (P < 0.05). The apoptotic rate and accumulation of intracellular ADM in the group of Fe₃O₄- MNP combined with ADM and As₂O₃were significantly higher than those in control, ADM, As₂O₃, and ADM plus As₂O₃groups (P < 0.05). The upregulation of BAX, P53 and Caspase-3 expression and the down regulation of BCL-2, NFκB, and Survivin expression at protein level were more remarkable in the group of ADM+As₂O₃ + MNP, compared with the other groups (P < 0.05). Moreover, the expressions of LC3 and Beclin-1 proteins in the group of ADM+As₂O₃+ MNP were higher, while the expression of P62/SQSTM1 was lower than that in other groups (P < 0.05).</p><p><b>CONCLUSION</b>The Fe3O4 - MNP combined with ADM and As₂O₃can increase the antitumor efficacy on Raji cells by promoting apoptosis and inducing autophagy. It would be a promising strategy for malignant lymphoma therapy.</p>

Modulus of elasticity of human periodontal ligament by optical measurement and numerical simulation.

OBJECTIVE: To determine the elastic modulus of the periodontal ligament (PDL). MATERIALS AND METHODS: This study was carried out on eight human maxillary jaw segments containing central incisors. Displacements were measured under load using a laser sensing system, electronic speckle pattern interferometry (ESPI). Subsequently, finite element models presenting the same individual geometry as the respective autopsy material were developed by the software of Mimics and Ansys, based on scanning data from micro computed tomography (micro CT), to simulate tooth mobility numerically under the same force systems as were used in the experiment. Numerical force/deflection curves obtained from the models were fitted to the experimental curves by repeatedly calculating theoretical tooth deflections and varying the elasticity parameters of the human PDL. RESULTS: A bilinear material parameter set was assumed to simulate tooth deflections. Mean values of E1  =  0.04 MPa, E2  =  0.16 MPa, and ultimate strain of ε12  =  7.3% were derived for the elastic behavior of the PDL. CONCLUSION: Force/deflection curves from the measurements showed a significant nonlinear behavior of elastic stiffness of the PDL. A bilinear material parameter set was suitably assumed to be a description of nonlinear properties of the PDL.

Effect of TIMP-2, MT1-MMP and MMP-2 expression on the in vitro invasive capacity of acute monocytic leukemia SHI-1 cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the effect of matrix metalloproteinase 2 (MMP-2), membrane type 1 MMP (MT1-MMP) and tissue inhibitor of metalloproteinase 2 (TIMP-2) expressions on the in vitro invasive capacity of acute monocytic leukemia SHI-1 cells.</p><p><b>METHODS</b>SHI-1, NB4, K562, M937 and THP-1 human leukemia cell lines were cultured in vitro. The mRNA and protein expressions of TIMP-2, MMP-2 and MT1-MMP in different cells were detected by quantitative RT-PCR and western blot. A retroviral vector carrying human TIMP-2 cDNA was constructed and transfected into SHI-1 cells. Three subclone cells (S1, S2 and S3) were screened by G418 and selected by limiting dilution. RNA interference (RNAi) was used to knock down the expression of MMP-2, MT1-MMP and TIMP-2. Cell invasion capacity was performed through a reconstituted human basement membrane assays. Zymography was used to analyze the expression of MMP-2 in the supernatant of co-culture.</p><p><b>RESULTS</b>The expressions of MMP-2, MT1-MMP and TIMP-2 in SHI-1 cells were higher than that in other leukemic cells at both mRNA and protein levels (P < 0.05). The amount of proMMP-2 and activated MMP-2 in the conditioned media from SHI-1 cells co-cultured with bone marrow stromal cells (BMSCs) was more than that from other cells (P < 0.05). The in vitro invasive capacity of SHI-1 cells were higher than that of other cells (P < 0.05). The mRNA levels of TIMP-2 were increased by about 3 fold, 2 fold and 1.5 fold in S1, S2 and S3 cells, respectively (P < 0.05), while the protein levels were by about 2.6 fold, 1.5 fold and 1.3 fold than that of SHI-1 cells, respectively (P < 0.01). The invasion rates of subclone cells demonstrated a 1.5 - 2.5 fold' elevation (P < 0.05) and activated MMP-2 from their supernatants increased by 1.5 - 2.0 fold (P < 0.01). The knock-down efficiency of siRNA was 85% to 98%. The down-regulation of TIMP-2, MMP-2 and MT1-MMP decreased the invasion rates of SHI-1 cells by 60% - 70%, 50% - 60% and 40% - 50%, respectively (P < 0.05). No activated MMP-2 in the supernatants from any knock-down cells could be found.</p><p><b>CONCLUSIONS</b>SHI-1 cells constitutively overexpress MMP-2, MT1-MMP and TIMP-2 at both mRNA and protein levels. After co-cultured with BMSCs the SHI-1 cells increased MMP-2 activation and cell invasion. An increase of TIMP-2 expression in SHI-1 cells reflects an activating effect on cells invasion and MMP-2 activation.</p>

Accuracy evaluation of computer aided design and computer aided manufacture template for implant placement / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The computer aided design and computer aided manufacture (CAD/CAM) template was fabricated basing on CT data of completely edentulous jaws, and the accuracy of template was evaluated by assessment of the deviation between the actual and planning position of the implant after the registration of pre- and post-operative CT images.</p><p><b>METHODS</b>The CAD/CAM templates for 4 completely edentulous jaws were designed and fabricated basing on the pre-operative CT data and the stone models of the jaws sample. And 14 implants were placed in the posterior region of the jaws aided by the CAD/CAM template. The pre- and post-operative CT was registered by the point to point method, and the deviation between actual and virtual implants was measured to assess the accuracy of the template.</p><p><b>RESULTS</b>With the aid of CAD/CAM template, the deviations of the position at the tail of the implant, at the tip of the implant and the projected deviation of angle were (0.19 +/- 0.07) mm, (0.47 +/- 0.12) mm, and 1.790 +/- 0.68 degrees respectively, and the deviations of the position at the bucco-palatal, disto-mesial, vertical direction were (0.22 +/- 0.08) mm, (0.25 +/- 0.06) mm, (0.30 +/- 0.11) mm at the tip respectively.</p><p><b>CONCLUSION</b>Within the limits of this study, the results verify the accuracy of CAD/CAM template and support its use for safety implant placement.</p>

Expression of Osterix mRNA and protein levels in cultured human periodontal ligament cells after mechanical stimulation / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To examine the expression of Osterix (Osx) mRNA and protein after application of mechanical force on human periodontal ligament cells (HPDLCs), and to investigate the role of Osx in orthodontic alveolar bone remodeling.</p><p><b>METHODS</b>HPDLCs were isolated and cultured in vitro with explant method. Approximately 2.5 x 10(5) cells were seeded onto six-well cell culture plates and then were exposed to centrifugal force for 1, 2, 4, 6, 8 or 12 h at 631 r x min(-1). The expression of Osx mRNA and protein was measured by reverse transcription-polymerase chain raction (RT-PCR) and Western blot respectively. Immunofluorescence assay was used to detect the expression and subcellular At the initial time point, Osx mRNA had a weak exlocalization of Osx protein by green fluorescence.</p><p><b>RESULTS</b>pression and protein was not detected. Under the mechanical stimulation, both mRNA and protein levels of Osx were upregulated in a time-dependent manner. Furthermore, Osx protein was translocated gradually from the cytosol into the cell nuclei.</p><p><b>CONCLUSION</b>The expression and activation of Osx were enhanced by mechanical stress in HPDLCs, which indicates that Osx may play an important role in HPDLCs osteogenic differentiation and periodontal tissue remodeling induced by mechanical stress.</p>

Influence of periodontal ligament injury on initial stability for immediately loaded mini-implant / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the influence of periodontal ligament (PDL) injury on initial stability for immediately loaded mini-implant anchorage.</p><p><b>METHODS</b>The sample consisted of 153 adult patients with maxillary protrusion deformity. Guiding by the positioning device designed by Choi, 306 mini-implants were inserted by self-tapping in the upper right and left buccal areas between the first molars and second premolars. The mini-implants were divided into two groups according to CT scanning. The mini-implant was absolutely separated from PDL (group I), the mini-implant appeared to touch or overlay on PDL, but not contact to the adjacent roots (group II). If orthodontic force could be applied to the mini-implants for four months, the mini-implant was recorded as successful anchorage. After immediate loading for four months, the analyses were completed by SPSS 9.0 software.</p><p><b>RESULTS</b>Of the 306 inserted mini-implants, 162 were absolutely separated from PDL, 136 appeared to touch or overlay on PDL, but not contact to the adjacent roots, and 8 were excluded from this study because of injury to the adjacent root. The success rates of group I and II were 87.0% and 65.4% respectively. There were significant differences in the success rates between the two groups (P<0.001). The differences between the two groups in distribution of the upper right and left area had statistical significance (P<0.05).</p><p><b>CONCLUSION</b>PDL injury is one of the main reasons leading to early loosening of the mini-implant.</p>

Effect of delayed sequential bone marrow transplantation on acute graft-versus-host disease in major H-2 incompatible mouse transplantation / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the effect of delayed sequential bone marrow transplantation on acute graft-versus-host disease (aGVHD) in major H-2 incompatible mouse transplantation.</p><p><b>METHODS</b>C57BL/6 (H-2b) mice were used as donors and BALB/c (H-2d) mice as recipients. BALB/c mice were given 8.0 Gys total body irradiation (TBI) on day 0 and infused with a blend of bone marrow cells and spleen cells in different time. Transplantation was carried out as follows: group I TBI on day 0 and transplantation at 4 h after TBI; groups of II TBI on day 0 and transplantation at 4 h, d1, d2, d3 after TBI; groups III TBI on day 0 and transplantation at day 4 after TBI; groups IV TBI on day 0 and transplantation at day 4 through day 7 after TBI. Recipient's spleen H-2b cells were detected by flow cytometry and the level of serum cytokines (IL-2, IL4, IL-6, IL-10 and IFN-gamma) by ELISA. The survival, aGVHD and hematopoietic recovery were observed.</p><p><b>RESULTS</b>aGVHD occurred in group I and the mice all died within 3 weeks after transplantation. The 60 day survival rates of groups of II and III were 30% and 50% respectively. The degree of aGVHD in group III was modest and the survival rate was higher than that in other groups (P <0.05). The peak time of IL-2, IFN-gamma, IL-4 and IL-10 in groups III and IV were later than that in group I. The levels of IL-4 and IL-10 in groups III and IV were higher than that in group I and for the levels of IL-2 and IFN-gamma were on the contrary (P < 0.05). The level of IL-6 in all groups peaked on day 5 to day 10 after TBI and was higher in group I than in others (P <0.05). In group IV the mean value of donor H-2b cells was (98.1 +/- 1.1)% on day 60 and WBC counts recovered normal on day 20.</p><p><b>CONCLUSIONS</b>Delayed sequential transplantation can reduce the morbidity of aGVHD ,improve the survival rate and not affect the engraftment and reconstitution of hematopoiesis in mouse allo-BMT. The mechanism of aGVHD prevention may be related to the reducing of type 1 cytokines of T lymphocyte and the increasing of type 2 cytokines.</p>