MSEC2007-31127 PVA-BASED SCAFFOLDS FOR THE REPAIR OF MUSCULOSKELETAL SOFT TISSUE

ABSTRACT The objective of this study was to design a partlydegradable scaffold to repair cartilage defects. The scaffold, based on poly(vinyl alcohol), PVA, was intended to maintain long-term mechanical integrity and to facilitate cell proliferation via bioactive agent release from contained microparticles, made from either alginate, ALG or poly(lacticco-glycolic acid), PLGA. The aim of this study was to characterize the morphological features and mechanical behaviour of composite scaffolds as a function of microparticle type and percent content. Our hypothesis was that the dynamic mechanical properties (Dynamic Modulus and Phase Angle) of the composite scaffold would not be affected by microparticle type, but that Dynamic Modulus would increase as a function of increased microparticle content. Scanning Electron Microscopy confirmed that the manufacturing process homogenously dispersed microspheres within the scaffolds. For pure PVA samples Dynamic Modulus ranged from 66±3 kPa at 0.01 Hz to 83±3 kPa at 50 Hz. As ALG microsphere content increased from 25 % to 75 %, Dynamic Modulus ranged from 92±5 kPa at 0.01 Hz to 153±19 kPa at 50 Hz. As the microsphere content increased from 25 % to 75 % PLGA, Dynamic Modulus ranged from 85±9 kPa at 0.01 Hz, to 157±16 kPa at 50 Hz. As expected, Dynamic Modulus increased with increasing test frequencies. For pure PVA specimens Phase Angle ranged from 4.3±0.8 degrees at 0.01 Hz to 12±1.2 degrees at 50 Hz. Phase Angle was not affected by microsphere content. In conclusion, the addition of microspheres affected the dynamic mechanical behavior, in particular Dynamic Modulus, of PVA scaffolds. However, the dynamic mechanical properties were not affected by the polymer from which the microspheres were manufactured. These findings suggest that microsphere type can be chosen to optimize the inclusion of bioactive factors, without detrimentally affecting the mechanical properties of the composite scaffold. It also suggests that % content of included microspheres can be used to modulate the mechanical properties of the scaffold at time zero

Surgical Approach for Long-term Survival of Patients With Intrahepatic Cholangiocarcinoma: A Multi-institutional Analysis of 434 Patients.

OBJECTIVES To examine the outcomes of a hepatectomy for intrahepatic cholangiocarcinoma (IHC) and to clarify the prognostic impact of a lymphadenectomy and the surgical margin. Large series of patients who were surgically treated for IHC are scarce. Thus, prognostic factors and long-term survival after resection of IHC remain uncertain. DESIGN Prospective study of patients who were surgically treated for IHC. Clinicopathologic, operative, and long-term survival data were analyzed. SETTING Prospectively collected data of all consecutive patients with pathologically confirmed IHC who had undergone liver resection with a curative intent at 1 of 16 tertiary referral centers were entered into a multi-institutional registry. PATIENTS All consecutive patients who underwent a hepatectomy with a curative intent for IHC (1990-2008) were identified from a multi-institutional registry. RESULTS A total of 434 patients were included in the analysis. Most patients underwent a major or extended hepatectomy (70.0%) and a systematic lymphadenectomy (62.2%). The incidence of lymph node metastases (overall, 36.9%) increased with increased tumor size, with 24.4% of patients with a small IHC (diameter 643 cm) having N1 disease. Almost one-third of patients required an additional major procedure to obtain a R0 resection in 84.6% of the cases. In these patients, the median time of survival was 39 months, and the 5-year survival rate was 39.8%. Lymph node metastases (hazard ratio, 2.21; P < .001), multiple tumors (hazard ratio, 1.50; P = .009), and an elevated preoperative cancer antigen 19.9 level (hazard ratio, 1.62; P = .006) independently predicted an adverse prognosis. Conversely, survival was not influenced by the width of a negative resection margin (P = .61). The potential survival benefit of a lymphadenectomy was assessed with the therapeutic value index, which was calculated to be 5.9 points. CONCLUSIONS Survival rates after a hepatectomy with a curative intent for IHC at tertiary referral centers exceed the survival rates reported in most study series in single institutions, which strengthens the value of an aggressive approach to radical resection. Lymph node metastases and multiple tumors are associated with decreased survival rates, but they should not be considered selection criteria that prevent other patients from undergoing a potentially curative resection. Lymphadenectomy should be considered for all patients

Inflammatory pseudotumor of the liver: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p>Inflammatory pseudotumor of the liver represents a fairly uncommon pathology. Although it is a benign tumor, the correct diagnosis can be missed.</p> <p>Case presentation</p> <p>We report the case of a 55-year-old Caucasian man, who presented with a one-month history of abdominal pain and weight loss. He was diagnosed with a primary liver tumor by computed tomography and magnetic resonance imaging. Alpha-fetoprotein levels ranged within normal limits. A right posterior sectorectomy was performed. Histopathology revealed an inflammatory pseudotumor of the liver. Our patient remains in good condition one year later.</p> <p>Conclusion</p> <p>Although inflammatory pseudotumor of the liver is usually a benign process, controversy regarding its management still exists. With this case report we review the existing literature and consider hepatectomy as a safe treatment approach.</p

Diagnostic and mechanistic implications of serum free light chains, albumin and alpha-fetoprotein in hepatocellular carcinoma

Background: Mass spectroscopy analysis suggested low serum albumin and high immunoglobulin free light chain (sFLC) levels may have diagnostic value in hepatocellular carcinoma (HCC). Our aims were to apply quantitative assays to confirm these observations, determine their diagnostic utility, and investigate the mechanisms involved. Methods: Albumin, sFLC, routine liver and renal function tests were measured in patients with chronic liver disease with (n=102) and without (n=113) HCC. The discriminant performance was compared with the current standard serological test alpha-fetoprotein (AFP) using receiver operating characteristic (ROC) and area under the curve (AUC) analyses. Results: sFLC and serum albumin were each confirmed to have discriminatory utility in HCC with AUC values of 0.7 and 0.8, respectively. sFLC were strongly correlated with gammaglobulin levels and both these were inversely related to serum albumin levels. The discriminatory utility of sFLC was retained after adjusting for renal and liver function. Conclusions: Serum levels of sFLC and albumin were strongly associated with HCC as predicted by mass spectroscopy. Discrimination of HCC by AFP was improved by the addition of either albumin or sFLC. Larger prospective studies are required to determine how AFP, sFLC and albumin might be combined in a useful diagnostic approach for HCC

Inhibitors of apoptosis proteins (IAPs) expression and their prognostic significance in hepatocellular carcinoma

<p>Abstract</p> <p>Background</p> <p>Similarly to other tumor types, an imbalance between unrestrained cell proliferation and impaired apoptosis appears to be a major unfavorable feature of hepatocellular carcinoma (HCC). The members of IAP family are key regulators of apoptosis, cytokinesis and signal transduction. IAP survival action is antagonized by specific binding of Smac/DIABLO and XAF1. This study aimed to investigate the gene and protein expression pattern of IAP family members and their antagonists in a series of human HCCs and to assess their clinical significance.</p> <p>Methods</p> <p>Relative quantification of IAPs and their antagonist genes was assessed by quantitative Real Time RT-PCR (qPCR) in 80 patients who underwent surgical resection for HCC. The expression ratios of XIAP/XAF1 and of XIAP/Smac were also evaluated. Survivin, XIAP and XAF1 protein expression were investigated by immunohistochemistry. Correlations between mRNA levels, protein expression and clinicopathological features were assessed. Follow-up data were available for 69 HCC patients. The overall survival analysis was estimated according to the Kaplan-Meier method.</p> <p>Results</p> <p>Survivin and Livin/ML-IAP mRNAs were significantly over-expressed in cancer tissues compared to non-neoplastic counterparts. Although Survivin immunoreactivity did not correlate with qPCR data, a significant relation was found between higher Survivin mRNA level and tumor stage, tumor grade and vascular invasion.</p> <p>The mRNA ratio XIAP/XAF1 was significantly higher in HCCs than in cirrhotic tissues. Moreover, high XIAP/XAF1 ratio was an indicator of poor prognosis when overall survival was estimated and elevated XIAP immunoreactivity was significantly associated with shorter survival.</p> <p>Conclusion</p> <p>Our study demonstrates that alterations in the expression of IAP family members, including Survivin and Livin/ML-IAP, are frequent in HCCs. Of interest, we could determine that an imbalance in XIAP/XAF1 mRNA expression levels correlated to overall patient survival, and that high XIAP immunoreactivity was a poor prognostic factor.</p

Osteochondral defects in the ankle: why painful?

Osteochondral defects of the ankle can either heal and remain asymptomatic or progress to deep ankle pain on weight bearing and formation of subchondral bone cysts. The development of a symptomatic OD depends on various factors, including the damage and insufficient repair of the subchondral bone plate. The ankle joint has a high congruency. During loading, compressed cartilage forces its water into the microfractured subchondral bone, leading to a localized high increased flow and pressure of fluid in the subchondral bone. This will result in local osteolysis and can explain the slow development of a subchondral cyst. The pain does not arise from the cartilage lesion, but is most probably caused by repetitive high fluid pressure during walking, which results in stimulation of the highly innervated subchondral bone underneath the cartilage defect. Understanding the natural history of osteochondral defects could lead to the development of strategies for preventing progressive joint damage

Simulated-Physiological Loading Conditions Preserve Biological and Mechanical Properties of Caprine Lumbar Intervertebral Discs in Ex Vivo Culture

Low-back pain (LBP) is a common medical complaint and associated with high societal costs. Degeneration of the intervertebral disc (IVD) is assumed to be an important causal factor of LBP. IVDs are continuously mechanically loaded and both positive and negative effects have been attributed to different loading conditions

Liver surgery in the presence of cirrhosis or steatosis: Is morbidity increased?

<p>Abstract</p> <p>Background data</p> <p>The prevalence of steatosis and hepatitis-related liver cirrhosis is dramatically increasing together worldwide. Cirrhosis and, more recently, steatosis are recognized as a clinically important feature that influences patient morbidity and mortality after hepatic resection when compared with patients with healthy liver.</p> <p>Objective</p> <p>To review present knowledge regarding how the presence of cirrhosis or steatosis can influence postoperative outcome after liver resection.</p> <p>Methods</p> <p>A critical review of the English literature was performed to provide data concerning postoperative outcome of patients presenting injured livers who required hepatectomy.</p> <p>Results</p> <p>In clinical studies, the presence of steatosis impaired postoperative outcome regardless the severity and quality of the hepatic fat. A great improvement in postoperative outcome has been achieved using modern and multidisciplinary preoperative workup in cirrhotic patients. Due to the lack of a proper classification for morbidity and a clear definition of hepatic failure in the literature, the comparison between different studies is very limited. Although, many surgical strategies have been developed to protect injured liver surgery, no one have gained worldwide acceptance.</p> <p>Conclusion</p> <p>Surgeons should take the presence of underlying injured livers into account when planning the extent and type of hepatic surgery. Preoperative and perioperative interventions should be considered to minimize the additional damage. Further randomized trials should focus on the evaluation of novel preoperative strategies to minimize risk in these patients. Each referral liver center should have the commitment to report all deaths related to postoperative hepatic failure and to use a common classification system for postoperative complications.</p