Clinical Evaluation of Continuous Renal Replacement Therapy Combined with Peritoneal Lavage for Severe Acute Pancreatitis: A Retrospective Cohort Study.

BACKGROUND We aimed to investigate the clinical efficacy of continuous renal replacement therapy (CRRT) in combination with peritoneal lavage for the treatment of severe acute pancreatitis. MATERIAL AND METHODS We retrospectively reviewed data from 52 patients with severe acute pancreatitis between January 2014 and December 2021 at Jiangyin People's Hospital. The patients were divided into 2 groups: CRRT (n=26) and CRRT in combination with peritoneal lavage (n=26). The following results and outcomes were retrospectively compared: procalcitonin, interleukin-6, and C-reactive protein levels, duration of systemic inflammatory response, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, abdominal distention relief time, abdominal pain relief time, length of intensive care unit stay, length of hospital stay, inpatient hospital costs, incidence of complications, and mortality. RESULTS There were significant differences in interleukin-6 and procalcitonin levels and APACHE-II scores after 3 and 7 days of treatment. The duration of systemic inflammatory response, abdominal distention relief time, abdominal pain relief time, length of intensive care unit stay, and length of hospital stay were considerably shorter in the combination group than in the CRRT group (P<0.01). Inpatient hospital costs were significantly lower in the combination group than in the CRRT group (P<0.01). However, incidence of complications and mortality showed no significant differences between the 2 groups. CONCLUSIONS CRRT combined with peritoneal lavage is an important adjuvant therapy in the early stages of acute severe acute pancreatitis and has better clinical efficacy than CRRT alone.

[1,2,4]Triazolo[1,5-a]pyrimidine derivative (Mol-5) is a new NS5-RdRp inhibitor of DENV2 proliferation and DENV2-induced inflammation.

Dengue fever is an acute infectious disease caused by dengue virus (DENV) and transmitted by Aedes mosquitoes. There is no effective vaccine or antiviral drug available to date to prevent or treat dengue disease. Recently, RNA-dependent RNA polymerase (RdRp), a class of polymerases involved in the synthesis of complementary RNA strands using single-stranded RNA, has been proposed as a promising drug target. Hence, we screened new molecules against DENV RdRp using our previously constructed virtual screening method. Mol-5, [1,2,4]triazolo[1,5-a]pyrimidine derivative, was screened out from an antiviral compound library (~8000 molecules). Using biophysical methods, we confirmed the direct interactions between mol-5 and purified DENV RdRp protein. In luciferase assay, mol-5 inhibited NS5-RdRp activity with an IC50 value of 1.28 ± 0.2 µM. In the cell-based cytopathic effect (CPE) assay, mol-5 inhibited DENV2 infectivity with an EC50 value of 4.5 ± 0.08 µM. Mol-5 also potently inhibited DENV2 RNA replication as observed in immunofluorescence assay and qRT-PCR. Both the viral structural (E) and non-structural (NS1) proteins of DENV2 were dose-dependently decreased by treatment with mol-5 (2.5-10 µM). Mol-5 treatment suppressed DENV2-induced inflammation in host cells, but had no direct effect on host defense (JAK/STAT-signaling pathway). These results demonstrate that mol-5 could be a novel RdRp inhibitor amenable for further research and development.

Postoperative recurrence of desmoid tumors: clinical and pathological perspectives.

BACKGROUND: The clinical features and the pathological changes of desmoid tumors were studied to point out the key factors affecting the recurrence. METHODS: The clinical data and specimens of 56 patients who underwent desmoid tumor resection from 2003 to 2008 were reviewed. Possible clinical factors related to the postoperative recurrence were analyzed statistically. The specimens round the lesions were studied histopathologically. RESULTS: The overall recurrence rate was 39.3%. The postoperative recurrence rate of the patients with negative surgical margins and no tumor invasion of the major vessels and nerves was low (P < 0.05). However, the desmoid tumors could destroy the cortical bone and invade the medullary cavity. CONCLUSIONS: Desmoid tumors were pathologically benign, which could extensively invade tissues around the lesions. The invasion of major vessels and nerves and quality of surgical margins are the key factors for the high postoperative recurrence rate.

[Surgical treatment and prognostic analysis of osteosarcoma in adults older than 40 years].

OBJECTIVE: To determine the prognostic factors of primary osteosarcoma in adults. METHODS: This is a review of 54 patients older than 40 years (24 men and 30 women) who were treated between 1998 and 2011 at the authors' institution. Demographic information and follow-up data were obtained and statistically analyzed. RESULTS: Tumors involved the limbs in 30 patients (55.5%) and axial skeleton in 17 patients (31.5%), and arose from soft tissue in 7 patients (13%). And 6 patients (11.1%) had synchronous metastasis. According to our review, tumors were treated surgically in 52 patients (96.3%). Local recurrence was documented in 14 patients (26.9%). Metastasis after diagnosis appeared in 21 patients (38.9%). In the 52 patients who received the surgical treatment, the 5 year disease-free survival and overall survival rates were 43.7% and 50.4%, respectively. CONCLUSION: Adult patients with primary osteosarcoma had a poor clinical outcome. Inadequate surgical margins, more tumors in the axial location due to high recurrence rates, metastatic disease at presentation, and large tumor volumes were associated with significantly lower survival rates. Aggressive multi-agent treatment regimens might improve survival.

[Surgical classification and therapeutic strategy for metastases of proximal femur].

OBJECTIVE: To establish a surgical classification system for metastases of proximal femur and discuss the therapeutic strategy with retrospective analysis and literature review. METHODS: The data of 99 patients who underwent a total of 102 operations for femoral metastatic lesions from January 2003 to December 2011 was analyzed. There were 50 males and 49 females, and the median age was 56 years (range 15-87 years). The most common diagnosis was lung cancer (30 cases), followed by breast cancer (17 cases). All femoral lesions were divided into 4 types (I-IV) with different anatomic site and biomechanic characteristic. The patients with various surgical reconstruction mode and postoperative follow-up data were recorded. RESULT: There were 65 side who received widely or marginal resection and 37 side who received intralesional resection. The patients were operated with bipolar hip prosthesis (n = 3), ordinary total hip replacement (THR) (n = 10), bipolar tumor prosthesis (n = 48), THR with tumor prosthesis (n = 8), intramedullary nailing (n = 21), and plate/screw (n = 12). The estimated survival for the 99 patients was 10.3 months. Type I, II, III and IV patients with postoperative American Society of bone and soft tissue tumors-93 rating were 86.5%, 77.3%, 81.3% and 69.1%. Patients with type IV were worse compared with the other 3 groups (t = 4.763, P = 0.031). The 10 operations were followed by complications of any kind. Complication rate of patients with type IV were 3/12, and it was significantly higher than the other 3 groups of patients (χ(2) = 4.018, P = 0.045). CONCLUSIONS: The classifications and corresponsive surgical methods for upper femur metastases had some superiority in hinting prognosis and guiding treatment.

[Prevalence and causes of blindness and moderate and severe visual impairment among adults aged 50 years or above in Changji City of Xinjiang Uygur Autonomous Region: the China Nine-Province survey].

OBJECTIVE: To investigate the prevalence and causes of blindness and moderate and severe visual impairment among adults aged ≥ 50 years in Changji City of Xinjiang Uygur Autonomous Region, China. METHODS: It was a population-based cross-section study.Geographically defined cluster sampling was used in randomly selecting 5714 individuals aged ≥ 50 years in Changji City. The survey was preceded by a pilot study where operational methods were refined and quality assurance evaluation was carried out. All participants were enumerated through village registers followed door-to-door visits.Eligible individuals were invited to received visual acuity measurement and eye examination. Prevalence of blindness and moderate and severe visual impairment was calculated according to different age, gender or education. And the reasons of blindness were analyzed.Statistical analyses were performed using Stata/SE Statistical Software, release 9.0. Chi-square test was used to investigate the association of age, gender and education with presenting and best corrected visual acuity. RESULTS: Five thousands seven hundreds and fourteen individuals were enumerated and 5250 persons were examined, the response rate was 91.88%. Based on the criteria of World Health Organization visual impairment classification in 1973, the prevalence of blindness and moderate and severe visual impairment defined as best corrected visual acuity was 0.74% (39/5250) and 3.83% (201/5250) respectively. The prevalence of blindness and moderate and severe visual impairment defined as presenting visual acuity was 1.33% (70/5250) and 8.02% (421/5250) respectively. The prevalence of blindness and moderate and severe visual impairment was higher in aged (trend χ(2) = 617.06, P = 0.000) , illiterate (trend χ(2) = 222.35, P = 0.000) persons. Cataract and was the first leading cause of blindness and visual impairment, the retinal diseases, including age-related macular degeneration, high myopic retinopathy, and diabetic retinopathy, were the second cause of blindness and visual impairment.Un-corrected refractive error was also the important cause of the visual blindness. CONCLUSIONS: The prevalence of blindness and moderate and severe visual impairment is not high among older adults aged ≥ 50 years in Changji City. The first main causes of blindness and visual impairment includes cataract, retinal diseases and un-corrected refractive error.

[Comparative analysis of clinical efficacy between posterior percutaneous endoscopic discectomy and anterior cervical discectomy and fusion in the treatment of cervical spondylotic radiculopathy].

OBJECTIVE: To explore the clinical efficacy of posterior percutaneous endoscopic discectomy(PPECD) in the treatment of cervical spondylotic radiculopathy. METHODS: A total of 56 patiens with single segment cervical spondylotic radiculopathy from December 2017 to October 2020, were randomly divided into observation group and control group. In observation group, there were 16 males and 11 females, including 8 cases of C4,5, 13 cases of C5,6 and 6 cases of C6,7 performed posterior percutaneous endoscopic discectomy, aged from 34 to 61 years old with an average of (51.15±6.29) years old. In control group, there were 19 males and 10 females with single segment cervical spondylotic radiculopathy including 10 cases of C4,5, 14 cases of C5,6 and 5 cases of C6,7 performed anterior cervical discectomy and fusion, aged from 40 to 65 years old with an average of (53.24±5.31) years old. The operative time, intraoperative blood loss, postoperative time of lying in bed and length of postoperative hospital stay were recorded. Visual analogue scale(VAS) and neck disability index(NDI) were used to evaluate the clinical efficacy. Cervical plain films or MRIs, CTs were taken for re-visiting patients. RESULTS: All patients were followed up more than 2 years. The observation group patients were followed up, the duration ranged from 24 to 42 months with an average of (30.48±4.91) months. The control group patients were followed up, the duration ranged from 25 to 47 months, with an average of (32.76±4.53) months. Compared with control group, operative time, intraoperative blood loss, postoperative time of lying in bed and length of postoperative hospital stay were decreased(P<0.05). Compared with pre-operation, VAS of neck and upper limb and NDI at the latest follow-up between two groups were significantly improved(P<0.05). Compared with control group, VAS of neck and upper limb at 1 day after operation in observation group were significantly reduced(P<0.05). There was no significant difference in VAS of neck and upper limb and NID at 1, 3 months and the latest follow-up after operation between two groups(P>0.05). In the observation group, one patient's deltoid muscle strength was weakened to grade 4 after operation, and returned to normal after 12 weeks of conservative treatment. In control group, there was 1 case of postoperative adjacent spondylosis with symptoms of spinal compression after 2 years operation, then underwent cervical artificial intervertebral disc replacement. And there was 1 case of dysphagia after operation in control group and improved after 1 year. There was no significant difference in incidence of complications between two groups. CONCLUSION: PPECD has advantages of shortening operative time, decreasing intraoperative blood loss, reducing postoperative time of lying in bed and length of postoperative hospital stay. However, applicable age range of patients and long-term clinical efficacy needs further study.

[Evaluation of efficacy and safety of rivaroxaban in the prevention of postoperative venous thromboembolism in adult patients with primary bone tumor undergoing knee operation].

OBJECTIVE: To explore the incidence of postoperative venous thromboembolism (VTE) in adult patients with primary bone tumor undergoing knee operation and evaluate its efficacy and safety in the prevention of VTE. METHODS: For this prospective, randomized and negative-control single-center trial, a total of 100 eligible patients were selected and randomly divided into observation and control groups. Observation group (rivaroxaban): the first rivaroxaban tablet was taken in the first 24 hours after operation. Rivaroxaban was administered daily every 24 hours up to Day 14. CONTROL GROUP: no anticoagulant was taken postoperatively. RESULTS: Efficacy indictors: 6 cases of DVT (an incidence of 12%) occurred in the observation group versus 15 (30%) in the control group. Significant statistical difference existed between two groups (P < 0.05). Furthermore, neither pulmonary embolism nor death was found in either group. Safety indicators:a total of 3 bleeding (1 major and 2 non-major) cases occurred in observation group versus a total of 2 bleeding (no major and 2 non-major) cases in control group. No significant statistical difference existed in bleeding events (P > 0.05). The total incidence of adverse effect was 6% (3/50) in the observation group. The drainage volume of the observation group was a little more than that of the control group. But no significant statistical difference existed in drainage duration (P > 0.05). And there was almost no change in the coagulation system by laboratory examination after oral administration. CONCLUSION: With an excellent safety profile and a low incidence of adverse effects, Rivaroxaban is effective and safe in the prevention of VTE in adult patients with primary bone tumor undergoing knee operation.

Surgical Treatment and Proposed Modified Classification for Harrington Class III Periacetabular Metastases.

OBJECTIVES: This study aims to: (i) evaluate the outcome of patients with Harrington class III lesions who were treated according to Harrington classification; (ii) propose a modified surgical classification for Harrington class III lesions; and (iii) assess the efficiency of the proposed modified classification. METHODS: This study composes two phases. During phase 1 (2006 to 2011), the clinical data of 16 patients with Harrington class III lesions who were treated by intralesional excision followed by reconstruction of antegrade/retrograde Steinmann pins/screws with cemented total hip arthroplasty (Harrington/modified Harrington procedure) were retrospectively reviewed and further analyzed synthetically to design a modified surgical classification system. In phase 2 (2013 to 2019), 62 patients with Harrington class III lesions were classified and surgically treated according to our modified classification. Functional outcome was assessed using the Musculoskeletal Tumor Society (MSTS) 93 scoring system. The outcome of local control was described using 2-year recurrence-free survival (RFS). Owing to the limited sample size, we considered P < 0.1 as significant. RESULTS: In phase 1, the mean surgical time was 273.1 (180 to 390) min and the mean intraoperative hemorrhage was 2425.0 (400.0 to 8000.0) mL, respectively. The mean follow-up time was 18.5 (2 to 54) months. Recurrence was found in 4 patients and the 2-year RFS rate was 62.4% (95% confidence interval [CI] 31.6% to 93.2%). The mean postoperative MSTS93 score was 56.5% (20% to 90%). Based on the periacetabular bone destruction, we categorized the lesions into two subgroups: with the bone destruction distal to or around the inferior border of the sacroiliac joint (IIIa) and the bone destruction extended proximal to inferior border of the sacroiliac joint (IIIb). Six patients with IIIb lesions had significant prolonged surgical time (313.3 vs 249.0 min, P = 0.022), massive intraoperative hemorrhage (3533.3 vs 1760.0 mL, P = 0.093), poor functional outcome (46.7% vs 62.3%, P = 0.093), and unfavorable local control (31.3% vs 80.0%, P = 0.037) compared to the 10 patients with IIIa lesions. We then modified the surgical strategy for two subgroup of class III lesions: Harrington/modified Harrington procedure for IIIa lesions and en bloc resection followed by modular hemipelvic endoprosthesis replacement for IIIb lesions. Using the proposed modified surgical classification, 62 patients in the phase 2 study demonstrated improved surgical time (245.3 min, P = 0.086), intraoperative hemorrhage (1466.0 mL, P = 0.092), postoperative MSTS 93 scores (65.3%, P = 0.067), and 2-year RFS rate (91.3%, P = 0.002) during a mean follow-up time of 19.9 (1 to 60) months compared to those in the phase 1 study. CONCLUSION: The Harrington surgical classification is insufficient for class III lesions. We proposed modification of the classification for Harrington class III lesions by adding two subgroups and corresponding surgical strategies according to the involvement of bone destruction. Our proposed modified classification showed significant improvement in functional outcome and local control, along with acceptable surgical complexity in surgical management for Harrington class III lesions.

[Finite element analysis for modular hemipelvic endoprosthesis during loaded gait cycle].

OBJECTIVE: To analyze the biomechanical characteristics of modular hemipelvic endoprosthesis in gait cycle using finite element analysis method, and the effect of pubic connection plate on stress distribution. METHODS: Three dimensional finite element model of periacetabular defect reconstructed with modular hemipelvic endoprosthesis was established. The hip contact forces, which were published from Free University of Berlin, under gait cycle were applied in the load of Abaqus 6.7. Then the simulation was conducted and four characteristic time points were identified, 17%, 36%, 43% and 86% of gait cycle. The von Mises stress distribution of the prosthesis was calculated. Stress concentration was ascertained and the difference of stress distribution between reconstruction with and without pubic connection plate was analyzed. The displacement and stress peak value of iliac fixation part under the four points of gait cycle were recorded; Comparison of stress on the four transverse iliac fixation screws was studied and the effect of pubic connection plate ascertained. RESULTS: During the gait cycle, both the stress peak and maximum displacement occurred in the single-leg stance phase, according to 17%-36% of gait cycle. More rational stress distribution could be achieved under the reconstruction with pubic connection plate at 17% and 86% of gait cycle, representing ipsilateral and contralateral single-leg stance respectively, resulting in more even distribution. The maximum stresses of the iliac fixation part were 148.5 MPa and 270.1 MPa under the reconstruction with and without pubic connection plate, with significant difference (P=0.04); The mean displacements of the iliac fixation part were 9.3 mm and 11.7 mm with and without pubic connection plate reconstruction (P=0.03). The average stress level of iliac fixation part could be decreased to 50% and 24% for the iliac fixation screws. However, no micromotions were decreased under the reconstruction with pubic connection plate. Also no significant difference was observed for the relative shift of the iliac fixation part with and without pubic connection plate (P=0.41). CONCLUSION: The stability of the implant could satisfy the normal walk activity. The pubic connection plate played an important role in the stability of the endoprosthesis, decreasing the stress peak and elongation of the durability.

[Ewing's sarcoma of bone:treatment results and prognostic factors].

OBJECTIVE: To determine the prognostic factors from the view of clinic and pathology. METHODS: A retrospective analysis was performed on a data set of 78 patients with Ewing's sarcoma treated at Peking University People's Hospital Musculoskeletal tumor center between July 1998 and July 2007. Five-year overall survival (OS), recurrence rate and prognostic factors were analyzed in this study. Univariate and multivariate analysis were performed to determine the prognostic factors for OS. RESULTS: Fifty-three cases were followed up, follow-up time ranged from 8.0 to 101.0 months (median 37.6 months). The 5-year overall survival rate and local recurrence rate were 33.7% and 20.8% respectively. Univariate showed age < 20 years, metastases free at diagnosis, tumor located at extremities, tumor size < 10 cm, adequate surgical margin had better survival rate (all P < 0.05). Multivariate analysis demonstrated that metastases at diagnosis, primary site and tumor size were independent prognostic factors for OS. CONCLUSION: The independent prognostic factors Ewing's sarcoma are metastases at diagnosis, primary site, tumor size.

Laparoscopic VS. Open splenectomy and oesophagogastric devascularisation for liver cirrhosis and portal hypertension: A retrospective cohort study.

BACKGROUND: We compared laparoscopic splenectomy combined with oesophagogastric devascularisation vs. open splenectomy combined with oesophagogastric devascularisation in patients with portal hypertension secondary to liver cirrhosis. MATERIALS AND METHODS: This study included 192 patients diagnosed with portal hypertension and severe gastroesophageal varices at our hospital between January 2002 and December 2018; 62 patients underwent laparoscopic splenectomy combined with oesophagogastric devascularisation (laparoscopic group), and 130 patients underwent the open procedure (open group). The results and outcomes were compared retrospectively. RESULTS: The median blood loss was significantly less in the laparoscopic group than in the open group (180 vs. 380 mL, P < 0.001). The length of hospitalisation was shorter (6 vs. 11 days, P < 0.001) and the complication rate was lower in the laparoscopic group (P < 0.001). The general complication rates were 23.8% and 4.8% (P < 0.001), and the surgical complication rates were 56.1% and 24.2% (P < 0.001) in the open and laparoscopic groups, respectively. During a postoperative follow-up period of 10-60 months, the incidence of oesophagogastric variceal rebleeding showed no significant difference between groups. CONCLUSION: Laparoscopic splenectomy combined with oesophagogastric devascularisation is technically feasible and safe in selected patients. Compared with the open group, the laparoscopic group showed a less volume of blood loss, shorter length of hospitalisation, and fewer postoperative complications but similar long-term outcomes.

[Lethal effects of nanoliposome encapsulated cisplatin on Saos-2 cells and its distribution in nude mice bearing human].

OBJECTIVE: To investigate the killing effect of nanoliposome encapsulated cisplatin (NLE-CDDP) on human osteosarcoma cell line Saos-2 and explore the distribution of platinum (Pt) in tumor-bearing mice. METHODS: Saos-2 cells were cultured at different concentrations of NLE-CDDP. MTT assay, inverted microscopic observation and flow cytometry assay(FCM)were used to observe the antiproliferative effect of NLE-CDDP on the human osteosarcoma cells. Antitumor effect of NLE-CDDP was determined using the xenografts models of human osteosarcoma cell Saos-2 in nude mice. The Pt concentration in the tissues of tumor-transplanted mice was determined by atomic spectrophotometer. RESULTS: When treated at different concentrations of NLE-CDDP for 24-96 hours, the survival rate of Saos-2 cells decreased significantly(P<0.05). At the same time point, the inhibitory effect of NLE-CDDP was stronger than that of CDDP;Degeneration and necrosis of Saos-2 cells increased; the apoptosis increased and the S phase reduced. This study demonstrated that NLE-CDDP had obvious anti-tumor activity. Within 1 hour of injection, in NLE-CDDP group plasma platinum concentration was 4.4-fold that in CDDP group; 2 hours later, platinum was not detected in the blood of CDDP group; 24 hours later, platinum still could be detected in NLE-CDDP group at 2.76 mumol/L. During the first hour after injection of NLE-CDDP, the platinum content of the kidney was 50% less than that of CDDP group. Platinum in NLE-CDDP group showed rapid higher accumulation in the liver, spleen and tumor compared with CDDP group, and within 24 hours platinum reached the peak concentration in the spleen. CONCLUSION: The antitumor efficacy of NLE-CDDP on Saos-2 tumor is higher than that CDDP alone, and its mechanism is delaying rapid clearance from circulation.

[Evaluation of neoadjuvant chemotherapy for patients with stage II osteosarcoma].

OBJECTIVE: To retrospectively review the effect of chemotherapy and survival rate of osteosarcoma in extremity. METHODS: Between July 1997 and July 2007, 296 patients with osteosarcoma received neo-adjuvant chemotherapy and surgery. There were 184 males and 112 females, with age between 7 and 65 years. The tumors located in proximal femur in 10 patients, diaphyseal of femur in 7, distal femur in 148, proximal tibia in 80, distal tibia in 5, fibula in 11, humerus in 33, and distal radius in 2 patients. According to Enneking stage system, 6 patients were in stage IIA and others in stage IIB. All patients received evaluation of preoperative chemotherapy, and 72 patients had analysis of tumor necrosis after operation. RESULTS: After mean follow-up of 47 months, metastasis developed in 98 (33.1%) patients. The metastatic rate was 15.5%, 31.0%, and 77.1% in patients with substantial effective chemotherapy, partial effective chemotherapy, and no effective chemotherapy, respectively. In tumor necrosis analysis, reduction of tumor volume and more clear margin after preoperative chemotherapy were related to higher tumor necrosis. CONCLUSIONS: The patients with osteosarcoma should receive chemotherapy as soon as possible. More effective chemotherapy means lower metastatic rate and higher no event survival rate.

[The surgical treatment of metastatic periacetabular tumors].

OBJECTIVE: To retrospectively review the experience with different surgical procedures for periacetabular metastasis. METHODS: The data of 43 patients with periacetabular metastasis between July 2000 and July 2007 was reviewed. There were 21 patients with primary malignant tumors at the beginning, and 10 patients diagnosed metastasis by preoperative biopsy. The other 12 patients presented skeletal involved as initial manifestations of metastasis prior to the pathological diagnosis of the primary tumor. Twelve patients had solitary metastasis, and the others had multiple bone metastasis. The surgical procedure included curettage (35 cases) and en-blot excision (8 cases). The techniques of reconstruction of acetabular defect included total hip replacement (THR) with cemented components or titanium acetabular reconstruction cup (12 cases), THR with partial pelvis replacement with Candal Hook (16 cases), THR with Steinmann pins and cement augmented or titanium cup reconstruction (7 cases), and modular hemipelvic prosthesis reconstruction (8 cases). RESULTS: All the patients received successful operations. The average score for preoperative pain of 7.2 was assessed. Forty-one patients (95.4%) were evaluated for relief of pain and resumption of walking, and the pain score improved to 3.5 after surgery. The average functional score was 24.5 postoperatively. Six of 32 patients had local recurrence. Fourteen patients died of diseases. The average blood loss during the operation was 1600 ml in 43 patients and the bleeding exceeded 3000 ml was in 3 patients with renal carcinomas. Major complications included two superficial wound infections, one multiple organ failure and two dislocations. CONCLUSIONS: Although surgery will not typically cure patients of their metastatic disease, surgery that is well planned and well executed can help many people by relieving their suffering and improving their quality of life.

[The surgical management of sacral chordoma].

OBJECTIVE: To analyze the surgical treatment results and experience of sacral chordoma. METHODS: The data of 51 cases of sacral chordoma surgically treated from July 1997 to July 2007 was retrospectively studied. The age of patients ranged from 21 to 75 years (mean 57 years), including 32 males and 19 females. Forty patients had the first surgery, while other 11 patients were referred to our hospital because of local recurrence from other hospital. Wide resection for all 17 S(3-5) tumors, and wide resection plus piece-meal excision for 34 tumors which involved S(3) above. Reconstruction was performed using pedicle screw and rod device to achieve the continuity between the lumbar spine and the pelvis. The oncologic and functional outcomes of 51 patients were reviewed. RESULTS: After a mean duration of follow-up of 3.5 years (range from 15 to 108 months), 5 of 51 patients died of disease. Seventeen of 40 (42.5%) patients who underwent first surgery recurred during follow-up, 18 of 28 patients (64.3%) got re-relapse after second or third surgeries. Postoperative wound complications were as high as 31.6%. CONCLUSIONS: Chordoma is a biologically aggressive low-grade malignant tumor. Wide resection is a prerequisite for curative treatment of sacrococcygeal chordoma, intralesional curettage causes the risk of high local recurrence for which curative resection in a second or third procedure is more difficult to achieve. In order to preserve near normal bowel and bladder function for the tumor which involves S(3) above, wide en-bloc resection plus piece-meal excision in the cephalad is performed.

Limb Salvage Using Non-hinged Endoprosthesis and Staged Correction of Leg-length Discrepancy for Children with Distal Femoral Malignant Tumors.

OBJECTIVE: Limb salvage in pediatric patients remains a challenge. We describe a staged strategy. The procedure includes: (i) tumor removal and non-hinged static endoprosthesis reconstruction; (ii) leg length discrepancy (LLD) correction by shoe lift or distraction osteogenesis; and (iii) maturity reconstruction by regular endoprosthesis. The aim of the study was to investigate the results of non-hinged static megaprosthesis reconstruction and staged LLD correction in the treatment of malignant tumors in the distal femur in children. METHODS: Non-hinged megaprostheses were implanted in 12 pediatric patients with osteosarcoma in the distal femur. The prosthesis consists of a femoral component with constrained condylar knee (CCK) design, and a tibial component with a small-diameter press-fit stem and derotation fins. A posterior stabilizing polyethylene component is fixed on the tibial component. The cases were prospectively followed up with focus on the growth rate of adjacent uninvolved bone in the salvaged limb, joint stability, knee stability, function outcome, length discrepancy, and surgery-related complications. RESULTS: There were five girls and seven boys included in the study, with an average age at the time of primary surgery of 10.0 years (range, 8-12 years). All the tumors were located in the distal femur. The average follow up was 76.3 months (range, 24-139 months). The Ligament Augmentation and Reconstruction System (LARS) ligament was used in two patients to enhance the soft tissue reattachment and reconstruct medial collateral ligament (MCL). Ten patients were alive at the final follow-up and two had died of lung metastases. Expected LLD was 6.7 cm (range, 3.0-13.2 cm) at initial surgery. At the final follow-up, nine patients reached skeletal maturity and the actual LLD at the femur was 5.3 cm (range, 3.0-10.1 cm), excluding 1 cm correction at initial surgery by endoprosthesis. The proximal tibia physis showed an average of 86.7% (range, 56.5%-100%) growth of the contralateral side. The mean reduction in tibial length was 1.2 cm (range, 0.5-4.7 cm). Six patients received distraction osteogenesis at a mean length of 5.4 cm (range, 3.0-9.1 cm). Range of knee movement was between 85° and 125°, with an average of 102.5°. The Musculoskeletal Tumor Society 93 score of patients alive was 80.6 (range, 60-90). CONCLUSION: Non-hinged static megaprosthesis followed by LLD correction with shoe lift or staged distraction osteogenesis appears to be an alternative option to treat children with malignant bone tumors around the knee.

Mediation in the second-order synaptic emulator with conductive atomic force microscopy.

Memristors have been extensively studied for synaptic simulation and neuromorphic computation. Instead of focusing on implementing specific synaptic learning rules by carefully engineering external programming parameters, researchers recently have paid more attention to taking advantage of the second-order memristor that is more analogous to biologic synapses and modulated not only by external inputs but also by internal mechanisms. However, experimental evidence is still scarce. Here, we explore a BiMnO3 memristor by applying simple spike forms. The filament evolution dynamics, including processes of forming and spontaneous decay, were directly observed by the conductive atomic force microscopy (c-AFM) technique. We propose that the unique conductance state of the BMO memristor is regulated by the oxygen vacancy (VO) dynamic process. We believe this primary result is helpful to improve understanding of the internal mechanisms of the second-order oxide memristor, which exhibits promising application in building selectors, memories and neuromorphic-computing systems.

[Surgical treatment and outcome of pelvic metastases].

OBJECTIVE: To retrospectively review the different types of surgical procedures for pelvic metastases, especially for periacetabular metastases. METHODS: Eighty-eight patients with pelvic metastasis received surgical treatment between July 1997 and July 2005. The series included 40 females and 48 males, with an average age of 54 years. The original sites of carcinoma included 23 from breast, 15 from lung, 13 form kidney, 3 from thyroid, 2 from bladder, 3 from prostate, 3 form liver, 7 from gastro intestine, and 3 from gynecological viscera Thirteen cases were diagnosed as unknown primary metastases. Thirty-two patients had solitary metastasis and 56 patients had multiple bone metastases. Eighteen patients had Type I pelvic resections, 50 had type II, and 10 patients had Type III and Type IV each. Surgical treatments included 72 intralesional curettages and 16 en bloc resections. In 29 patients, the bone defect after tumor resection was reconstructed with methyl acrylate alone or combined with Steinmann pins and screw-rod system. Acetabular reconstructions underwent in 50 patients. Local resections with no reconstructions were done in 5 patients, and hemipelvectomy in 4 patients. RESULTS: The mean time of follow-up was 13 months, ranging from 6 to 24 months. Twenty-nine patients were lost follow-up. Postoperative improvements in 86 (97.8%) patients were seen in pain and mobility scores. The average VAS pain scores were 7.2 points preoperatively and 3.5 points postoperatively. Postoperative function was evaluated according to Enneking's criteria, with a mean score of 19.2 points, including 16.4 points for periacetabular lesions and 23.5 for others. Local recurrence was seen in 11 patients, the average recurrence time was 5.6 months after surgery. Surgical complications occurred in 12 patients, including 8 wound complications, 2 multi-organ function failures, 1 pulmonary embolism, and 2 dislocations. CONCLUSIONS: The indications of surgical intervention for pelvic metastasis are severe pain and difficulty in ambulation. The surgical objective is alleviation of pain, restore the mobility and stability of the hip. The surgical procedure for most metastases is curettage and cement filling. Wide resection is an alternative method for solitary pelvic metastasis with good prognosis.