Deleterious effects of discography radiocontrast solution on human annulus cell in vitro: changes in cell viability,proliferation, and apoptosis in exposed cells

Background contextCarragee et al. have recently shown that modern discography injections are associated with subsequent acceleration of disc degeneration, herniation, and loss of disc height. Although needle puncture and pressurization are known trauma events that can create disc degeneration in animal models, another likely culprit in clinical discography–associated degeneration is a direct effect of the contrast agent itself on disc cells.PurposeTo test the hypothesis that discography contrast solution would have a deleterious effect on human annulus cells in vitro.Study designAn in vitro study using cultured human annulus cells to assay cell death, cell proliferation, and apoptosis.Patient sampleAnnulus cells from eight surgical disc specimens were evaluated (two Thompson Grade III discs and six Grade IV discs) for cell death and proliferation, and an additional five cultures were tested for apoptosis.Outcome measuresThe proportion of dead and live cells, cell proliferation, and the proportion of apoptotic cells in control and experimental groups.MethodsAfter internal review board approval, experimental design used two sets of controls: untreated cells under our normal culture conditions (control) and a set with added glucose to adjust the osmolality to match respective Isovue radiocontrast solution treatments (glucose controls) using a freezing point osmometer. Treated cells received Isovue 200 (iopamidol, Isovue-M 200; Bracco Diagnostics, Inc., Princeton, NJ, USA) at 12.5, 25, 50, or 100 mg/mL. Twenty thousand cells/well were seeded in triplicate in 24 well plates, control or test media added, and incubated for 24 hours. At termination, dead cells were identified with trypan blue staining and percentage dead cells determined. Cells were also tested to determine the percentage of apoptotic cells after 50 or 100 mg/mL Isovue exposures. Proliferation assays used standard plate reader methods. Statistical analysis used repeated measures analysis of variance with SAS software (version 9.2; SAS Institute, Inc., Cary, NC, USA).ResultsAnalysis of cell death showed a significant increase in the percentage of dead cells with increasing Isovue concentrations compared with control cells (p=.018–.0008). Cell proliferation analyses showed significantly reduced division in Isovue-treated cells (p=.004), and apoptosis assays revealed a significantly higher proportion of apoptotic cells in cells exposed to 50 and 100 mg/mL Isovue (p=.016 and .0003, respectively).ConclusionsDiscography is used extensively in the evaluation of low back pain. Because the lifetime prevalence of disc degeneration and low back pain is high (80% in the general population), many patients may undergo this procedure. Data presented here show that cells exposed in vitro to a radiocontrast agent with adjustments for osmolality have significantly reduced proliferation, increased cell death, and increased programmed cell death (apoptosis). In light of the well-recognized age- and degeneration-related decrease in disc cell numbers, it is possible that radiocontrast exposure may be contributing significantly to disc cell loss with subsequent progression of disc degeneration. Findings presented here provide a plausible cell-based explanation for the previously reported disc degeneration in patients receiving discography contrast solutions.     

Aggressive surgery for metastatic liver neuroendocrine tumors

BACKGROUND: Neuroendocrine tumors of the gastrointestinal tract (carcinoids, pancreatic endocrine tumors) have low malignant potential but can decrease survival rates if they spread to the liver (LNET). METHODS: The records of 16 patients with LNET primarily from gastrointestinal carcinoids treated surgically were retrospectively reviewed. RESULTS: There were 12 women and 4 men. Median age was 56 years (range 25 to 75). Thirteen (81%) had a carcinoid tumor and 5 had gastrinoma. Two patients with multiple endocrine neoplasia type 1 had both a gastric carcinoid and a jejunal gastrinoma. Eight patients (50%) had the carcinoid syndrome. Each patient had all identifiable LNET either resected or ablated. Ten patients had liver wedge resections, 1 right trisegmentectomy, 5 left hepatic lobectomies, and 2 radiofrequency ablations. Thirteen (81%) patients had concomitant bowel resections. Two patients had concomitant total gastrectomies to remove stomach primaries. The final patient had an extraintestinal pelvic primary or a liver primary. There were no operative deaths, and all 8 (100%) patients with the carcinoid syndrome had amelioration of symptoms. The 5-year actuarial survival rate was 82% with a median follow-up of 32 months. CONCLUSIONS: This study demonstrates that liver and concomitant extrahepatic surgery can be performed safely in patients with liver metastases because of carcinoids or pancreatic endocrine tumors. It results in excellent long-term survival and amelioration of symptoms. Surgery should be the first-line therapy for patients with LNET.     

Morbidity and mortality of aggressive resection in patients with advanced neuroendocrine tumors

BACKGROUND: There is considerable controversy about the treatment of patients with malignant advanced neuroendocrine tumors of the pancreas and duodenum. Aggressive surgery remains a potentially efficacious antitumor therapy but is rarely performed because of its possible morbidity and mortality. HYPOTHESIS: Aggressive resection of advanced neuroendocrine tumors can be performed with acceptable morbidity and mortality rates and may lead to extended survival. DESIGN: The medical records of patients with advanced neuroendocrine tumors who underwent surgery between 1997 and 2002 by a single surgeon at the University of California, San Francisco, were reviewed in an institutional review board-approved protocol. MAIN OUTCOME MEASURES: Surgical procedure, pathologic characteristics, complications, mortality rates, and disease-free and overall survival rates were recorded. Disease-free survival was defined as no tumor identified on radiological imaging studies and no detectable abnormal hormone levels. Proportions were compared statistically using the Fisher exact test. Kaplan-Meier curves were used to estimate survival rates. RESULTS: Twenty patients were identified (11 men and 9 women). Of these, 10 (50%) had gastrinoma, 1 had insulinoma, and the remainder had nonfunctional tumors; 2 had multiple endocrine neoplasia type 1, and 1 had von Hippel-Lindau disease. The mean age was 55 years (range, 34-72 years). In 10 patients (50%), tumors were thought to be unresectable according to radiological imaging studies because of multiple bilobar liver metastases (n = 6), superior mesenteric vein invasion (n = 3), and extensive nodal metastases (n = 1). Tumors were completely removed in 15 patients (75%). Surgical procedures included 8 proximal pancreatectomies (pancreatoduodenectomy or whipple procedure), 3 total pancreatectomies, 9 distal pancreatectomies, and 3 tumor enucleations from the pancreatic head. Superior mesenteric vein reconstruction was done in 3 patients. Liver resections were done in 6 patients, and an extended periaortic node dissection was performed in 1. The spleen was removed in 11 patients, and the left kidney was removed as a result of tumor metastases in 2. Eighteen patients had primary pancreatic tumors, and 2 had duodenal tumors; 2 patients with multiple endocrine neoplasia type 1 had both pancreatic and duodenal tumors. The mean tumor size was 8 cm (range, 0.5-23 cm). Of the patients, 14 (70%) had lymph node metastases and 8 (40%) had liver metastases. The mean postoperative hospital stay was 11.5 days (range, 6-26 days). Six patients (30%) had postoperative complications. There was a significantly greater incidence of pancreatic fistulas with enucleations compared with resections (P =.04). There were no operative deaths. The mean follow-up period was 19 months (range, 1-96 months); 18 patients (90%) are alive, 2 died of progressive tumor, and 12 (60%) are disease-free. The actuarial overall survival rate is 80% at 5 years, and disease-free survival rates indicate that all tumors will recur by the 7-year follow-up visit. CONCLUSIONS: Aggressive surgery including pancreatectomy, splenectomy, superior mesenteric vein reconstruction, and liver resection can be done with acceptable morbidity and low mortality rates for patients with advanced neuroendocrine tumors. Although survival rates following surgery are excellent, most patients will develop a recurrent tumor. These findings suggest that conventional contraindications to surgical resection, such as superior mesenteric vein invasion and nodal or distant metastases, should be reconsidered in patients with advanced neuroendocrine tumors.     

Metal-on-metal hip resurfacing: the effect of cup position and component size on range of motion to impingement

The aim of this dry bone study was to determine the range of hip motion to impingement for different hip resurfacing cup positions and component sizes. The maximum angles of hip flexion, extension, abduction, and adduction were calculated from 3-dimensional coordinates for: 1. Cup inclination of 30 degrees , 40 degrees , 50 degrees , 60 degrees , and 70 degrees with fixed anteversion; 2. Cup anteversion of 0 degrees , 10 degrees , 25 degrees , 35 degrees , and 45 degrees with fixed inclination; and 3. 3 different component sizes on the same size dry bones. An acetabular component inclination of 50 degrees and an anteversion of 25 degrees allowed the most physiologic range of hip motion. A larger-diameter femoral component relative to the native femoral neck diameter resulted in a greater range of hip motion to impingement.     

Evaluation of adhesion formation, mesh fixation strength, and hydroxyproline content after intraabdominal placement of polytetrafluoroethylene mesh secured using titanium spiral tacks, nitinol anchors, and polypropylene suture or polyglactin 910 suture

Background The purpose of this study is to evaluate fixation methods for polytetrafluoroethylene (ePTFE) mesh with an in vivo model of laparoscopic ventral hernia repair.Methods In 40 New Zealand white rabbits, a 4 × 4-cm ePTFE mesh (n = 80, two per animal) was attached to an intact peritoneum with polyglactin 910 (PG 910) (n = 20) or polypropylene (PP) (n = 20) suture, titanium spiral tacks (TS) (n = 20), or nitinol anchors (NA) (n = 20). Mesh was harvested at 8 and 16 weeks for fixation strength testing, adhesion assessment, and collagen (hydroxyproline) content. Fixation strength on day 0 was determined with mesh attached to harvested abdominal wall. Statistical significance was determined as p < 0.05.Results There was no difference in fixation strength between PP (39.1 N) and PG 910 (40.0 N) sutures at time zero. At week 8, PP (25.7 N) was significantly stronger (p < 0.05) than PG 910 (11.4 N) suture, but not at week 16. The fixation strength of TS and NA (day 0, 15.4 vs 7.4 N; week 8, 17.5 vs 15.3 N; week 16, 19.1 vs 13.8 N) was not significantly different. Fixation with PP suture was significantly (p < 0.05) stronger than that with TS and NA at day 0 (39.1, 15.4, and 7.4 N, respectively) but not at weeks 8 or 16. The fixation strength of suture decreased significantly (p < 0.05) from day 0 to week 16 (PP: day 0 = 39.1 N, week 8 = 25.7 N, week 16 = 21.4 N; PG 910: day 0 = 40.0 N, week 8 = 11.4 N, week 16 = 12.8 N). The fixation strength of NA and TS did not change significantly (NA: day 0 = 7.4 N, week 8 = 15.3 N, week 16 = 13.8 N; TS: week 0 = 15.4 N, week 8 = 17.5 N, week 16 = 19.1 N). There were no differences in adhesion area based on fixation device used; however, there were more (p < 0.05) mesh samples using NA with adhesions compared to TS and adhesion tenacity was greater (p < 0.05) compared to that of TS, PP, and PG. Hydroxyproline content at weeks 8 and 16 was similar for all fixation devices.Conclusions The initial fixation strength for nonabsorbable suture is significantly greater than that of the metallic fixation devices, but after 8 weeks there is no difference. Laparoscopic ventral hernia repair without transabdominal suture fixation may be predisposed to acute failure. The metallic devices have similar fixation strength, although the incidence of adhesions and tenacity of adhesions appear to be greater with the nitinol anchors. Since these devices have similar fixation strengths and most likely provide adequate supplementation to transabdominal sutures for mesh fixation after laparoscopic ventral hernia repair, their use should be based on other factors, such as their propensity for adhesions, ease of application, and cost.Paper presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Denver, Colorado, USA, March 31–April 3, 2004     

恶性肿瘤靶向给药的临床应用

恶性肿瘤靶向给药是指利用具有一定肿瘤靶向性的导向分子（载体）携带治疗肿瘤的药物,在肿瘤局部选择性杀伤肿瘤细胞（及转移的肿瘤细胞）,以避免药物的全身毒副作用,提高疗效的一种治疗方法．由于抗癌药物在杀伤肿瘤细胞的同时也杀伤正常细胞,增加了全身的毒副作用．因此,近几年来,对恶性肿瘤靶向治疗的研究突飞猛进,发展了人源性抗HER-2mAb、依西美坦、放射性核素、     

BMC Medicine celebrates its 5th anniversary

In November 2008, BMC Medicine passed the landmark of its first 5 years of publishing. When we launched the journal with the aim of publishing high quality research of general interest and special importance, we had no idea what the future would bring. To mark the occasion of our 5^th anniversary, we consider the achievements of the last 5 years and discuss our plans for the future.     

Radiation jejunitis and a choleic-acid enterolith

Digestive Diseases and Sciences - A case is presented of a woman with jejunal stricture resulting from X-irradiation 20 years previously and a choleic-acid enterolith lying above the site of...     

Effectiveness of diclofenac versus paracetamol in knee osteoarthritis: a randomised controlled trial in primary care

Background

The effectiveness of diclofenac versus paracetamol in primary care patients with pain caused by knee osteoarthritis is unclear.

Aim

To assess the effectiveness of diclofenac compared with paracetamol over a period of 2, 4, and 12 weeks in patients with knee osteoarthritis.

Design and setting

Randomised controlled trial in general practice.

Method

There were 104 patients included in the study, they were aged ≥45 years consulting their GP with knee pain caused by knee osteoarthritis. Patients were randomly allocated to diclofenac (n = 52) or paracetamol (n = 52) for at least 2 weeks. Primary outcomes were daily knee pain severity, and knee pain and function measured with the Knee Injury and Osteoarthritis Outcome Score (KOOS).

Results

Over a period of 2- and 4-weeks follow-up, no significant difference in daily knee pain was found between the patient groups: estimated differences of 0.5 (95% CI = −0.2 to 1.3) and −0.2 (95% CI = −1.0 to 0.7), respectively. Over the 12-weeks follow-up, no significant differences were found between both groups for KOOS pain: estimated difference of −2.8 (95% CI = −10.7 to 5.1) and KOOS function of −2.7 (−10.6 to 5.0).

Conclusion

Over a period of 2- and 4-weeks follow-up no significant difference in daily measured knee pain severity was found between primary care patients with knee osteoarthritis taking paracetamol or diclofenac. Also, over a period of 12-weeks follow-up no significant differences were found regarding KOOS pain and KOOS function between both groups. Patients more frequently reported minor adverse events after taking diclofenac (64%) than paracetamol (46%).