[Clinical study of double plate system in the treatment of complex proximal humeral fractures in the elderly].

OBJECTIVE: To explore the clinical outcomes of anteromedial combined with lateral locking plate for complex proximal humeral fractures in the eldery. METHODS: From June 2018 to October 2020, 30 patients who underwent surgical treatment for Neer grade 3 to 4 proximal humeral fractures, including 8 males and 22 females, aged from 51 to 78 years old with an average of (61.5±7.5) years old. Of them, 15 patients had fractures fixed with anteromedial combined with lateral locking plate(ALLP group), whereas 15 received internal fixation with proximal humerus locking plate only(PHLP group). The clinical data, simple shoulder test (SST), humeral head height loss, varus angle and shoulder range of motion were compared between the two groups. RESULTS: All fractures were healed. The follow-up time ranged from 12 to 24 months, with an average of(14.3±2.9) months. The operation time of ALLP group was longer than that of PHLP group (P<0.05). There was no significant difference in intraoperative blood loss between the two groups (P>0.05). There was no significant difference in SST score between the two groups at 1, 3 and 12 months after operation (P>0.05). In terms of radiographic measurement, there was no significant difference in humeral head height loss and varus angle between the two groups at 1 and 3 months after operation (P>0.05). At 12 months after operation, the height loss and varus angle of humeral head in ALLP group were lower than those in PHLP group (P<0.05). In shoulder range of motion, the range of forward elevation in ALLP group was larger than that in PHLP group 1 year after operation(P<0.05). There was no significant difference in external rotation between the two groups. CONCLUSION: Anteromedial combined with lateral locking plate in the treatment of complex proximal humeral fractures in the elderly can increase the stability of the medial column and obtain a good fracture prognosis. But there are also disadvantages such as longer operation time, so it should be individualized according to the fracture type of the patient.

Variation in Global Spinal Sagittal Parameters in Asymptomatic Adults with 11 Thoracic Vertebrae, four Lumbar Vertebrae, and six Lumbar Vertebrae.

OBJECTIVE: To investigate the prevalence of 11 thoracic vertebrae (TVs), four lumbar vertebrae (LVs) and six LVs among asymptomatic Chinese volunteers, and the influence of spine variations on the global spinal sagittal parameters. METHODS: A total of 389 asymptomatic Chinese volunteers were recruited. Each subject underwent a full-spine X-ray examination with measurement of global spinal sagittal parameters. The radiographs were examined by a spine surgeon and a radiologist to determine the variation in the number of vertebrae. These parameters were used to compare individuals with five LVs to those with 11 TVs, four LVs, and six LVs. RESULTS: The study population included 12 individuals (3.1%) with seven cervical vertebrae (C) + 11 thoracic vertebrae (T) + five lumbar vertebrae (L), 8 (2.1%) with 7C + 11T + 6L, 8 (2.1%) with 7C + 12T + 4L, and 15 (3.9%) with 7C + 12T + 6L. Compared to the 7C + 12T + 5L individuals, those with 7C + 11T + 5L had significantly lower C6 -T5 Cobb values (P < 0.05); 7C + 12T + 4L individuals had significantly greater thoracic inlet angles (P < 0.05) and significantly lower pelvic tilt (P < 0.05); individuals with 7C + 12T + 6L had significantly greater sacral slope, pelvic tilt, pelvic incidence, and L1-5 Cobb values (all P < 0.05), but significantly lower thoracic inlet angle (P < 0.05). There were no significant differences in any of the parameters examined between the 7C + 11T + 6L group and the 7C + 12T + 5L group. CONCLUSIONS: Asymptomatic adults with 7C + 12T + 6L, 7C + 12T + 4L, and 7C + 11T + 5L presented with different spinal sagittal alignment compared to those with 7C + 12T + 5L. Compared to variation in the number of LVs, the variation in the number of TVs had less effect on global spinal sagittal parameters. Spinal surgeons and researchers should be aware of the effects of variation in numbers of TVs and LVs on global spinal parameters and sagittal balance.

[Prognosis and Genetic Characteristics of Patients with Plasma Cell Leukemia].

OBJECTIVE: To evaluate the clinical characteristics, genetic abnormalities, treatment efficacy and prognostic factors in patients with plasma cell leukemia(PCL). METHODS: 30 patients diagnosed as PCL in our hospital from January 1993 to December 2019 were enrolled, and the clinical characteristics, laboratory findings, therapeutic regimes, and survival data of the patients were retrospectively analyzed. RESULTS: The median age of the 30 patients was 56.5 (28-80) years old, among them, 25 patients were primary plasma cell leukemia, and 5 patients were secondary plasma cell leukemia. Complex karyotypes and subdiploids were most common in cytogenetic abnormalities. Among the 20 cases of chromosome G banding, 11 (55%) cases were complex karyotypes and 8 (40%) cases were hypodiploid. Fluorescent in situ hybridization (FISH) test showed that among 11 cases, 6 cases showed 17p13 deletion, 8 cases showed at least two kinds of abnormalities, which including t (14; 16), t (8; 14), t (11;14), 17p13 deletion, and 13q14 deletion. The median overall survival (OS) time was 10.5 months for all patients. The median OS time of the patients in ECOG score ≤ 2 group was 21.5 months, which was significantly longer than those in the ECOG score>2 group(1.2 months) (P=0.017). The median OS time of the patients treated with novel agents (including proteasome inhibitor and/or immunomodulator) was 24.9 months, which was significantly longer than the patients treated with traditional chemotherapy group(10.5 months) (P＜0.001). For the patients treated with novel agents, the median OS time of patients accepted two novel agents combination was 30.9 months, which was longer than those of single novel agent(11.5 months) (P=0.021). The effect of genetic abnormolity to the OS of the patients showed no statistical difference. Multivariate statistical analysis showed that ECOG score>2 was the independent prognostic factor of plasma cell leukemia patients. There were two patients underwent allogeneic hematopoietic stem cell transplantation in the study,but died due to the pulmonary infection within 6 months after transplantation. CONCLUSION: In the era of novel agents, ECOG score is an independent prognostic factor of plasma cell leukemia. Multiple novel agents treatment should be underwent as soon as possible to improve the prognosis of the patients. Pulmonary infection is a common factor that cause the death of the patients after allogeneic hematopoietic stem cell transplantation.

Factors Associated with Cervical Spine Alignment in an Asymptomatic Population: A Preliminary Analysis.

BACKGROUND: Cervical sagittal imbalance compromises health-related quality of life and can lead to myriad incapacitating symptoms through compression of the spinal cord. Questions regarding which parameters play primary roles in the progression of cervical sagittal imbalance and which might be compensatory factors remain unanswered. METHODS: This study enrolled 246 asymptomatic volunteers from July 2016 to June 2018. After demographic and radiologic parameters were measured, the data were analyzed using correlation coefficient test and multiple regression analysis. A predictive equation was assessed with variance analysis, residual analysis, collinearity analysis, and a paired t test. RESULTS: Average values are as follows: orbital tilt, 64 ± 6°; orbital slope (OS), 15 ± 6°; C0-C2 lordosis (C0C2), 28 ± 8°; cervical lordosis (CL), 5 ± 11°; C2-C7 sagittal vertical axis (C2C7SVA), 15 ± 8 mm; T1 slope (TS), 17 ± 6°; thoracic inlet angle, 69 ± 8°; thoracic kyphosis, 34 ± 9°; lumbar lordosis, 50 ± 10°; sacral slope, 38 ± 7°; pelvic index, 48 ± 9°; sagittal vertical axis, 10 ± 19 mm. Correlations of C2C7SVA were observed with body mass index (BMI), OS, C0C2, CL, and TS. The validated predictive equation was: C2C7SVA = 0.38 × BMI - 0.73 × OS + 0.73 × C0C2 + 0.15 × CL + 0.18 × TS - 6.53. CONCLUSIONS: BMI, OS, C0C2, CL, and TS were primary influencers in the progression of cervical sagittal imbalance and established a predictive equation of asymptomatic population, which can provide clinical advice and remind surgeons of the primary influencers of reconstructive surgery for better prognoses.

Biomechanical properties of novel transpedicular transdiscal screw fixation with interbody arthrodesis technique in lumbar spine: A finite element study.

PURPOSE: The purpose of this study was to investigate finite element biomechanical properties of the novel transpedicular transdiscal (TPTD) screw fixation with interbody arthrodesis technique in lumbar spine. METHODS: An L4-L5 finite element model was established and validated. Then, two fixation models, TPTD screw system and bilateral pedicle screw system (BPSS), were established on the validated L4-L5 finite element model. The inferior surface of the L5 vertebra was set immobilised, and moment of 7.5 Nm was applied on the L4 vertebra to test the range of motion (ROM) and stress at flexion, extension, lateral bending and axial rotation. RESULTS: The intact model was validated for prediction accuracy by comparing two previously published studies. Both of TPTD and BPSS fixation models displayed decreased motion at L4-L5. The ROMs of six moments of flexion, extension, left lateral bending, right lateral bending, left axial rotation and right axial rotation in TPTD model were 1.92, 2.12, 1.10, 1.11, 0.90 and 0.87°, respectively; in BPSS model, they were 1.48, 0.42, 0.35, 0.38, 0.74 and 0.75°, respectively. The screws' peak stress of above six moments in TPTD model was 182.58, 272.75, 133.01, 137.36, 155.48 and 150.50 MPa, respectively; and in BPSS model, it was 103.16, 129.74, 120.28, 134.62, 180.84 and 169.76 MPa, respectively. CONCLUSION: Both BPSS and TPTD can provide stable biomechanical properties for lumbar spine. The decreased ROM of flexion, extension and lateral bending was slightly more in BPSS model than in TPTD model, but TPTD model had similar ROM of axial rotation with BPSS model. The screws' peak stress of TPTD screw focused on the L4-L5 intervertebral space region, and more caution should be put at this site for the fatigue breakage. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: Our finite element study provides the biomechanical properties of novel TPTD screw fixation, and promotes this novel transpedicular transdiscal screw fixation with interbody arthrodesis technique be used clinically.

Acceptable Chin-Brow Vertical Angle for Neutral Position Radiography: Preliminary Analyses Based on Parameters of the Whole Sagittal Spine of an Asymptomatic Chinese Population.

OBJECTIVE: We sought to acquire the whole sagittal spine parameters and investigated the acceptable chin-brow vertical angle (CBVA) for neutral position radiography in an asymptomatic Chinese population. METHODS: The parameters measured in 257 asymptomatic volunteers included CBVA, occipital slope, orbital tilt, occipital incidence, C0-C2 Cobb angle, C2-C7 Cobb angle, C1-C7 Cobb angle, C2-C7 sagittal vertical axis and absolute rotation angle, cervical tilt, cranial tilt, T1 slope, and thoracic kyphosis, and others. We used Pearson correlation analyses to find relationships between CBVA and other variables. The subjects were divided into 5 groups according to the CBVA percentile: group A, 0%-20% CBVA; group B, 20%-40% CBVA; group C, 40%-60% CBVA; group D, 60%-80% CBVA; and group E, 80%-100% CBVA. We used analysis of variance to analyze differences among the 5 groups. RESULTS: Orbital tilt, Occipital incidence, C1-C7 Cobb angle, C2-C7 sagittal vertical axis, and cranial tilt all increased with increasing CBVA (P < 0.001). The occipital slope, C2-C7 Cobb angle, C2-C7 absolute rotation angle, cervical tilt, T1 slope, and thoracic kyphosis decreased with decreasing CBVA (P < 0.05). No correlations between other sagittal parameters and the CBVA were found. A slight deviation was found in groups B-D, with a greater deviation in groups A, C, and E. CONCLUSIONS: An acceptable range of -1.5° to 5.8° is recommended for the CBVA for cervical radiography in the neutral position. When spinal surgeons evaluate the cervical plane, the effects of the CBVA deviation on cervical curvature must be considered.

Rate of presence of 11 thoracic vertebrae and 6 lumbar vertebrae in asymptomatic Chinese adult volunteers.

BACKGROUND: An increasing number of studies on spinal morphology in asymptomatic Asian and Western patients have been reported. Variation in spinal anatomy among patients is considered as the cause of wrong-level surgery in up to 40% of cases. The present study examined the rate of presence of 11 thoracic vertebrae and 6 lumbar vertebrae in 293 asymptomatic Chinese adult volunteers. METHODS: From May 27, 2016, to November 11, 2017, a cohort of 325 asymptomatic Chinese adults meeting the study exclusion criteria was recruited. The radiographs were examined by a spine surgeon and a radiologist to assess the number of thoracic and lumbar vertebrae. RESULTS: In total, 293 volunteers were included in this study: 17 (5.8%) had 11 thoracic vertebrae, and 16 (5.5%) had 6 lumbar vertebrae. Among all volunteers, 12 (4.1%) had 7 cervical vertebrae (C), 11 thoracic vertebrae (T), and 5 lumbar vertebrae (L); 5 (1.7%) had 7C, 11T, and 6L; and 11 (3.8%) had 7C, 12T, and 6L. There was no difference between the findings of the spine surgeon and the radiologist. CONCLUSIONS: For the first time, this study describes the rate of presence of 11 thoracic vertebrae and 6 lumbar vertebrae in 293 asymptomatic Chinese adult volunteers. Variations in the number of thoracic and lumbar vertebrae tend to be ignored by spine surgeons. We encourage spinal surgeons and researchers to be aware of such variations when performing thoracic- and lumbar-level surgery and assessing spinal alignment and parameters.

A Novel Knotless Barbed Suture Technique for Traumatic Thoracolumbar Fracture in Posterior Surgery.

BACKGROUND: Surgical wound closure directly influences spinal surgical efficiency and several postoperative complications. The traditional suture technique is time-consuming and associated with greater rates of complications. Bidirectional absorbable barbed sutures seem to compensate for some of the limitations of traditional suture; however, they rarely are reported in spinal surgery. We designed a novel suture technique for use in thoracolumbar spinal surgery. METHODS: The data of 189 patients with traumatic thoracolumbar fractures were analyzed between bidirectional barbed suture closure and traditional interrupted suture closure. Data of operative time, wound closure time, length of incision, intraoperative blood loss, complications of wound dehiscence and postoperative hematoma, cost, and neurologic status were collected. RESULTS: No significant differences were observed in the baseline demographics of included patients. Compared with the traditional suturing group, the barbed sutures decreased the mean operative time (P = 0.037), suture time (P < 0.01), and mean suturing time (P < 0.01) significantly, although no statistically significant differences were found in blood loss (P = 0.724) and neurologic functional scores (preoperative: P = 0.901; 3 months after surgery: P = 0.208; final follow-up assessments: P = 0.163), and no statistically significant differences were found in rates of postoperative infection, hematoma, and wound dehiscence. CONCLUSIONS: Our findings suggest that the novel knotless barbed suture has comparable strength to traditional sutures, with the advantage of less suturing time. It is an efficient, safe technique, and alternative choice for patients with thoracolumbar fracture after posterior surgery.

Normal radiological anatomy of thyroid cartilage in 600 Chinese individuals: implications for anterior cervical spine surgery.

BACKGROUND: Thyroid cartilage is an important barrier in anterior cervical approach surgery. The objective of this study is to establish normative values for thyroid cartilage at three planes and to determine their significance on preoperative positioning and intraoperative traction in surgery via the anterior cervical approach. METHODS: Neck CT scans were collected from 600 healthy adults who did not meet any of the exclusion criteria. Transverse diameters (D1, D2, and D3) of the superior border of the thyroid cartilage (SBTC), inferior border of the thyroid cartilage (IBTC), and the trachea transverse diameters of the inferior border of the cricoid cartilage (IBCC) were measured on a horizontal plane. RESULTS: All measured variables had intra-class correlation coefficients (ICCs) of ≥ 0.7. The differences in transverse diameters on the same plane between males and females were significantly different (all p < 0.001). The SBTC is most often at C4 in women (59.5%) and C4/5 in men (36.4%), the IBTC is most often at C5 in women (48.1%) and men (46.2%), and the IBCC is primarily located at C6 in women (45.2%) and C6 or C6/7 in men (34.4%) (all p < 0.001). CONCLUSION: We present normative values for thyroid cartilage at three planes of SBTC, IBTC, and IBCC in Chinese individuals. The individual and gender differences in the location of the thyroid cartilage and the size of the thyroid cartilage and the cricoid cartilage provide an anatomical basis to localize the skin incision, to predict the difficulty of intraoperative exposure and retractor pulling, and to identify that the thyroid cartilage protected the pharyngoesophageal wall.

Does the Iliac Wing Influence L5 Pedicle Screw Fixation?

OBJECTIVE: To explore whether the iliac wing influences L5 pedicle screw (PS) fixation and to propose methods to reduce such influence. METHODS: A total of 100 computed tomography scans (from 50 male and 50 female patients) of the lower lumbar region and pelvis were obtained and 3-dimensionally reconstructed. Cylinders with 6.5-mm diameters were drawn to simulate the different trajectories of L5 PS. The maximum lengths and lateral angles of trajectories, and the vertical distances from the inner edge of the iliac wing to these trajectories, were measured. RESULTS: The maximum lengths and lateral angles differed significantly among trajectories; the maximum length, but not the lateral angle, differed significantly between male and female subjects. The influence of the iliac wing was more significant in male than in female subjects. The iliac wing had a greater effect on screws implanted along the pedicle axis than on screws for which the trajectories commenced at Du's entry point and passed through the center of the pedicle. CONCLUSIONS: This study elucidates the influence of the iliac wing on L5 PS fixation. Careful attention is required when implanting PSs, especially in male patients. The combined use of Du's technique and a percutaneous method for PS implantation effectively reduces the influence of the iliac wing. To minimize the complications of PS fixation further, preoperative simulation of fixation for each patient is very important.

Biomechanical Role of the Thoracolumbar Ligaments of the Posterior Ligamentous Complex: A Finite Element Study.

OBJECTIVES: To investigate the effect of sequential ligament failure on the range of motion (ROM) and location of the instantaneous axes of rotation (IAR) of the thoracolumbar spine (T12-L1) finite element (FE) model, and to verify the role of the supraspinous ligament (SSL) in maintaining the stability of the injured thoracolumbar spine. METHODS: An FE model of the fractured thoracolumbar spine was developed and validated against published data. The posterior ligamentous complex (PLC) in the fractured T12-L1 segment was then reduced in a sequential manner from the facet capsular ligament (FCL), part of the interspinous ligament (ISL), SSL, and entire ISL, to the ligamentum flavum (LF). The ROM and IAR of the T12-L1 segment were measured at the fracture and at each reduced ligament step under 4 directions of flexion, extension, lateral bending, and rotation, and 4 bending motions of 1.5, 3.0, 4.5, 6.0 Nm. RESULTS: The FE model showed a consistent increase in the ROM and location of the IAR as the ligaments were removed sequentially. Furthermore, failure of the SSL had the most significant influence on the change in the ROM and IAR in flexion. In extension, removal of the FCL caused the largest shift. CONCLUSIONS: The SSL is a significant ligament that allows the PLC to maintain the stability of the thoracolumbar spine during injury.

Sirt6 overexpression suppresses senescence and apoptosis of nucleus pulposus cells by inducing autophagy in a model of intervertebral disc degeneration.

Treatment of intervertebral disc degeneration (IDD) seeks to prevent senescence and death of nucleus pulposus (NP) cells. Previous studies have shown that sirt6 exerts potent anti-senescent and anti-apoptotic effects in models of age-related degenerative disease. However, it is not known whether sirt6 protects against IDD. Here, we explored whether sirt6 influenced IDD. The sirt6 level was reduced in senescent human NP cells. Sirt6 overexpression protected against apoptosis and both replicative and stress-induced premature senescence. Sirt6 also activated NP cell autophagy both in vivo and in vitro. 3-methyladenine (3-MA) and chloroquine (CQ)-mediated inhibition of autophagy partially reversed the anti-senescent and anti-apoptotic effects of sirt6, which regulated the expression of degeneration-associated proteins. In vivo, sirt6 overexpression attenuated IDD. Together, the data showed that sirt6 attenuated cell senescence, and reduced apoptosis, by triggering autophagy that ultimately ameliorated IDD. Thus, sirt6 may be a novel therapeutic target for IDD treatment.

Gastrodin reduces IL-1ß-induced apoptosis, inflammation, and matrix catabolism in osteoarthritis chondrocytes and attenuates rat cartilage degeneration in vivo.

Therapeutics for osteoarthritis (OA) are intended to restore chondrocyte function and inhibit cell apoptosis. Previous studies have shown that gastrodin had anti-apoptotic and anti- inflammatory effects. However, little is known about whether gastrodin has protective effects against the processes of OA. We studied the potential effects of gastrodin on chondrocytes and the underlying mechanisms. Our results showed that gastrodin could prevent chondrocyte apoptosis induced by IL-1ß. Additionally, gastrodin suppressed the nuclear factor kappa B (NF-κB) pathway, decreased the release of inflammatory mediators (IL-6, TNF-α), and reduced matrix catabolism in IL-1ß-treated chondrocytes. Furthermore, gastrodin ameliorated rat cartilage degeneration in an OA model of knee joints in vivo, suggesting its potential as a candidate therapeutic for OA.

Panax quinquefolium saponin inhibits endoplasmic reticulum stress-induced apoptosis and the associated inflammatory response in chondrocytes and attenuates the progression of osteoarthritis in rat.

Treatments for osteoarthritis (OA) seek to restore chondrocyte function and inhibit cell apoptosis. Panax quinquefolium saponin (PQS) is the major active ingredient of Radix panacis quinquefolii (American ginseng), and has been demonstrated to exert anti-inflammatory and anti-apoptotic effects in various diseases. However, any potential effect of PQS on the pathological process of OA remains unclear. This work aimed to explore the role of PQS in chondrocytes and to clarify its potential mechanisms. We showed that PQS treatment could protect chondrocytes against endoplasmic reticulum (ER) stress and associated apoptosis induced by interleukin (IL)-1ß. Also, PQS further attenuated triglyceride (TG)-induced ER stress and associated apoptosis. Moreover, PQS may inhibit the ER stress-activated NF-κB pathway and associated inflammatory response in chondrocytes. Finally, PQS abolished rat cartilage degeneration in an in-vivo OA model of the knee joint. Our results indicate that PQS may be a potential novel treatment for OA.

Analysis of flavonoids and antitumor activity of transgenic Saussurea involucrate / 中国中药杂志

The aim of this paper was to investigate the flavonoids of callus of transgenic and non-transgenic Saussurea involucrate and its antitumor activity on the esophageal cancer CaEs-17 cells. The species and content of mono-phenols were detected by high performance liquid chromatography. The growth of human esophageal cancer CaEs-17 cells was detected using CCK-8 assay, apoptosis morphology observation and flow cytometry. Expression of related apoptotic genes Bax and Bcl-2 were determined by qPCR. The results showed that the content of total flavonoids in the transgenic callus was 2.72 times that of the non-transgenic callus. The cyanidin-galactoside was detected in the transgenic callus, but not in the non-transgenic callus. The inhibitory effect of the extracts from the transgenic callus on CaEs-17 cells was more significant than that of the non-transgenic callus, and the IC₅₀ value had a decreased of 26.4%. Flow cytometry analysis results showed that the apoptosis induction effect of the extracts from the transgenic callus on CaEs-17 cells was significantly better than that of the non-transgenic callus. Fluorescence quantitative PCR analysis results showed that the extracts from the transgenic callus could up-regulate the expression of proapoptotic gene Bax and down-regulate the expression of apoptotic gene Bcl-2, and the regulation effect of the transgenic callus was more significant. Therefore, compared with the non-transgenic callus, the antitumor activity of the extracts from the callus of transgenic S. involucrate on the esophageal cancer CaEs-17 cells was significantly increased, which was closely related to the accumulation of cyanidin-galactoside and its metabolism-related flavonoid compounds in the transgenic callus.

ShRNA-mediated silencing of MDM2 inhibits growth of HepG2 hepatocellular carcinoma cells xenografted in nude mice / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To construct a short hairpin (sh)RNA targeting the gene encoding the MDM2 oncoprotein in order to investigate its role in human hepatocellular carcinoma (HCC) and its potential for use as a gene therapy strategy to inhibit HCC growth in vivo.</p><p><b>METHODS</b>Small interfering (si)RNAs were designed targeting the MDM2 gene (siMDM2-1 and siMDM2-2) and unrelated sequences (negative control) and cloned into the expression plasmid pGCSilencer-U6-neo-GFP. A HCC mouse model was established by subcutaneous inoculation of HepG2 cells (2 x 10(6) in 0.2 ml) into 20 nude mice. The inoculated mice were divided into four equal groups for tumor-localized injections of saline, negative control siRNA plasmid, siMDM2-1 plasmid, and siMDM2-2 plasmid. Tumor growth was observed daily (by caliper measurement) for one month, when mice were sacrificed by cervical dislocation. The tumor mass was resected for analysis of tumor inhibition rate (% = [(average tumor weight of control group - average tumor weight of treatment group) / average tumor weight of control group x 100]) and effects on MDM2 and p53 mRNA and protein expression (by reverse transcription- PCR and western blotting, both normalized to beta-actin). Significance of between-group differences was assessed by one-way ANOVA or LSD test; pairwise comparisons were made by the Chi-squared test.</p><p><b>RESULTS</b>siMDM2-1 and siMDM2-2 suppressed the xenografted tumor growth remarkably (60.6% and 54.6% inhibition rates, respectively), significantly reduced the expression ofMDM2 gene (62.8% and 61.6%) and protein (60.7% and 59.5%), and significantly increased p53 gene (47.1% and 45.6%) and protein (45.9% and 44.3%) (all, P < 0.05).</p><p><b>CONCLUSION</b>shRNA-mediated silencing of the MDM2 gene effectively inhibits HCC tumorigenesis of subcutaneously xenografted HepG2 cells in nude mice, and the mechanism may involve p53.</p>

Effect of 90Sr-90Y ophthalmic applicator on corneal neovascularization after alkali burn / 中华实验眼科杂志

Background Corneal neovascularization ( CNV ) is a complication of many ocular surface diseases.It often worsen the pathological course.Effective therapy for CNV is still researching. Objective This study was to investigate the inhibitory effect of irradiation on CNV. Methods CNV models were established in 70 right eyes of 70 clean Wistar rats by corneal alkali burning.The models were randomized into β ray 10 Gy once irradiation group( 2 eyes),β ray 7 Gy multiple irradiation group( 17 eyes),β ray 10 Gy multiple irradiation group( 17 eyes),1％ cyclosporin A ( CsA ) eye drops group ( 17 eyes) and model group ( 17 eyes),and 6 matched normal rats were used as normal controls.All treatments started from the first day of the corneal alkali burning.CNV length and area were measured under the slit lamp every day.Corneal samples and homogenate were prepared 3,5,7 days after corneal alkali burning.The expressions of bcl-2,bax,vascular endothelial growth factor(VEGF) in rat corneas were detected by immunochemistry,VEGF proteins and VEGF mRNA were detected by Western blot and reverse transcription polymerase chain reaction (RT-PCR),respectively. Results Corneal ulceration was found in the βray 10 Gy once irradiation group and β ray 10 Gy multiple irradiation group.CNV length and area were much less in the β ray 7 Gy multiple irradiation group and 1％ CsA eye drops group compared with the model group on the seventh day after experiment( length:q=14.40,24.20,P＜0.01 ;area:q=17.80,14.00,P＜0.01 ).Immunochemistry revealed that compared with the model group,expressions of bcl-2 and VEGF proteins were weaker,but the expression of bax protein was stronger in the β ray 7 Gy multiple irradiation group and 1％ CsA eye drops group.RT-PCR showed that the expression of VEGF mRNA in cornea was lower in the β ray 10 Gy multiple irradiation group,β ray 7 Gy multiple irradiation group and 1％ CsA eye drops group in comparison with that in model group,and the results from Western blot showed the same pattern as RT-PCR. Conclusions Low dose irradiation of 90Sr-90Y ophthalmic applicator inhibits CNV formation after alkali burn.The study provide a new understanding of the irradiation for the treatment of CNV.

Therapeutic effects of small interfering RNA targeting MDM2 on human osteosarcoma cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the inhibitory effect of the small interfering RNA targeting mdm2 gene on the growth of osteosarcoma cells.</p><p><b>METHODS</b>PGCsilencerTM-mdm2 siRNA was constructed and transfected into the osteosarcoma cell line U2OS cells. The inhibitory effects on mdm2 were determined by RT-PCR and Western blot analysis. The cell growth activity was determined by MTT assay, and the cell apoptosis was examined by flow cytometry. The therapeutic effects of simdm2 was assessed on the nude mouse model of transplanted tumor.</p><p><b>RESULTS</b>The simdm2 plasmid was successfully constructed. After simdm2 being transfected into the U2OS cells, the expressions of mdm2 gene and protein were significantly inhibited. The ability of cell growth activity decreased greatly and cell apoptosis occurred apparently. There was no significant difference between the negative control group and non-transfected group. The growth of xenograft tumor in simdm2 transfected nude mice was inhibited and the expressions of mdm2 gene and protein were down-regulated remarkably.</p><p><b>CONCLUSION</b>siRNA targeting mdm2 gene inhibits the mdm2 expression in osteosarcoma U2OS cells and the growth of osteosarcoma in nude mice.</p>