Acute injury of the ligaments of the knee: magnetic resonance evaluation

Eleven acutely injured knees and 13 normal knees were examined by magnetic resonance imaging (MRI) to assess the value of this modality in detecting acute ligamentous injury of the knee. The presence of torn ligaments in the injured knees was determined by arthroscopy and/or arthrotomy in ten cases and clinical follow-up in one case. The anterior and posterior cruciate ligaments (ACL and PCL) were demonstrated by sagittal spin echo (SE) images through the intercondylar notch (TE = 30 ms; TR = 2,000 ms). The tibial and fibular collateral ligaments (TCL and FCL) were evaluated on coronal SE images (TE = 30 ms, TR = 200 or 530 ms; TE = 120 ms, TR = 2,000 or 2,120 ms). The ACL and PCL were considered torn on MR if they appeared disrupted or were not seen in their normal anatomical positions. The collateral ligaments were considered torn if abnormal high-intensity signal was noted in adjacent soft tissues on TE = 120 ms images or if disruption of a ligament was apparent. Eleven of 15 torn ligaments and 80 of 81 normal ligaments were correctly identified by these criteria. It is concluded that MR imaging may be useful in detecting acute injury of ligaments of the knee.     

Sensitive colorimetric assay of carbidopa and methyldopa using tetrazolium blue chloride in pharmaceutical products

A colorimetric method for the assay of carbidopa and methyldopa either in pure form or in pharmaceutical preparations is described. The method is based on the reduction of tetrazolium blue chloride in a non-aqueous alkaline medium by the substances analysed, and the measurement of the absorbance of the pink-coloured diformazan solution, which is caused by this reduction. The spectra of the aforesaid solutions exhibit an absorption maximum at= 525 nm. The apparent molar absorptivities and Sandell's sensitivities (in 1·mol^–1 ·cm^–1 and ng· cm^–2, respectively) are 1.2·10⁵ and 1.9 for carbidopa and 7.07· 10⁴ and 3.0 for methyldopa. The solution of diformazan formed obeys Beer's law in the concentration range of 0.05–4.0 ppm for carbidopa and 0.1–6.0 ppm for methyldopa. The slope and intercept of the corresponding regression line equation were obtained with a correlation coefficient of 0.9999 for carbidopa and 0.9994 for methyldopa. The variables affecting the development of the colour are investigated and the conditions are optimized. Compared with other procedures this method showed to be more simple and rapid, highly sensitive, precise and accurate. Results obtained by application of the proposed method and the official one, were in good agreement, while statistical comparison by the Student's t-test shows no significant difference between the two sets of the results.     

Three‐dimensional mapping of the creatine kinase enzyme reaction rate in muscles of the lower leg

Phosphorus (³¹P) magnetization transfer (MT) techniques enable the non‐invasive measurement of metabolic turnover rates of important enzyme‐catalyzed reactions, such as the creatine kinase reaction (CK), a major transducing reaction involving adenosine triphosphate and phosphocreatine. Alteration in the kinetics of the CK reaction rate appears to play a central role in many disease states. In this study, we developed and implemented at ultra‐high field (7T) a novel three‐dimensional ³¹P‐MT imaging sequence that maps the kinetics of CK in the entire volume of the lower leg at relatively high resolution (0.52 mL voxel size), and within acquisition times that can be tolerated by patients (below 60 min). We tested the sequence on five healthy and two clinically diagnosed type 2 diabetic subjects. Overall, we obtained measurements that are in close agreement with measurements reported previously using spectroscopic methods. Importantly, our spatially resolved method allowed us to measure local CK reaction rate constants and metabolic fluxes in individual muscles in a non‐invasive manner. Furthermore, it allowed us to detect variations of the CK rates of different muscles, which would not have been possible using unlocalized MRS methods. The results of this work suggest that 3D mapping of the CK reaction rates and metabolic fluxes can be achieved in the skeletal muscle in vivo at relatively high spatial resolution and with acquisition times well tolerated by patients. The ability to measure bioenergetics simultaneously in large areas of muscles will bring new insights into possible heterogeneous patterns of muscle metabolism associated with several diseases and serve as a valuable tool for monitoring the efficacy of interventions. Copyright © 2013 John Wiley & Sons, Ltd.     

Clinicopathological correlations in a series of adult patients with non‐alcoholic fatty liver disease

Possible correlations among clinical data, serum aminotransferase levels and histological features were assessed in a series of 37 adult patients with non‐alcoholic fatty liver disease (NAFLD), consisting of nine patients with fatty liver (FL) and 28 with non‐alcoholic steatohepatitis (NASH). In each liver biopsy, the NAFLD activity score (NAS) and the stage of fibrosis were determined. Additionally, the number of Kupffer cell aggregates (microgranulomas) per centimeter of biopsy length (MG/cm ratio) was assessed on immunohistochemical stains for CD68 antigen. Definite NASH (NAS ≥ 5) was strongly correlated with serum aspartate aminotransferase (AST) level (P= 0.003), stage of fibrosis (P= 0.003) and age (P= 0.014). On multivariate analysis, age >46 years and AST level above normal values were found to be independent clinical predictors of established NASH. The MG/cm ratio increased from control liver to FL to NASH (P < 0.001), and was correlated with the NAS (P= 0.003) and with the stage of fibrosis (P= 0.004), but not with the serum aminotransferase levels. In conclusion, persistent AST elevation in patients with suspected NAFLD should be an indication for liver biopsy, in order to determine the severity of necroinflammatory activity and the stage of fibrosis. Microgranuloma counting may represent a useful complementary marker of necroinflammatory activity in patients with NAFLD.     

Recurrence of primary biliary cirrhosis and development of autoimmune hepatitis after liver transplant: A blind histologic study

Aim:  This long-term study aimed to evaluate recurrence and evolution of primary biliary cirrhosis (PBC) after orthotopic liver transplantation (OLT).
Methods:  We reviewed "blindly" allograft biopsy specimens of women who underwent transplantation for PBC ( n  = 84), and women who received a transplant for chronic hepatitis C virus infection (CHCV ) ( n  = 108). All needle liver biopsy specimens obtained more than 6 months post-OLT were examined, including 83 specimens from 44 PBC patients and 152 specimens from 58 CHCV patients.
Results:  Granulomatous destructive cholangitis was found in five biopsies from four PBC patients ( P  = 0.0048). Non-necrotizing epithelioid cell granulomas were present in four biopsies from four PBC patients, and in two biopsies from one CHCV patient. Piecemeal necrosis ( P  = 0.0002), lobular necroinflammatory activity ( P  < 0.0001), steatosis ( P  < 0.0001) and fibrosis ( P  < 0.0001) were more prevalent in CHCV patients than PBC patients. Four PBC patients developed histologic evidence of autoimmune hepatitis (AIH), at a mean time of 3.66 years post-OLT. One of these patients had histologic features of AIH/PBC overlap syndrome. All four patients developed bridging fibrosis ( n  = 2) or cirrhosis ( n  = 2). No other PBC patient had evidence of cirrhosis after OLT.
Conclusions:  Histologic findings indicative of recurrent PBC were present in 15.9% of the PBC patients undergoing biopsy in this series. However, this group of patients did not suffer significant bile duct loss or fibrosis, as compared to the control group, suggesting that recurrent PBC is a mild or slowly progressive disease. Histologic evidence of AIH was observed in allograft biopsies of some PBC patients.     

Success, safety, and efficacy of implantation of diamond-like carbon-coated stents

The aim of this study was to evaluate safety and clinically defined efficacy of the implantation of a new stent coated with diamond-like carbon (DLC stent), in a group of patients who underwent percutaneous transluminal coronary revascularization procedures in two hemodynamic centers. This study was an observational prospective nonrandomized study that included 196 patients with a total of 236 significant de novo atheromatous coronary lesions, in which 245 DLC stents were implanted. The primary end point of this study was a composite of major cardiovascular events (death or acute myocardial infarction with or without Q) and need for target lesion revascularization (TLR) or target vessel revascularization (TVR) procedure during the first 48 hours and at 6 months after the DLC stent implantation. All patients had a myocardial perfusion imaging study with Tl(201) at 6 months after DLC stent implantation. Only patients with a myocardial perfusion imaging study indicative of myocardial ischemia were then submitted for a new coronary angiogram. No major cardiovascular event or emergency TVR occurred during hospitalization. At 6-month follow-up no major cardiovascular event occurred either, whereas the rate for TLR was 5.6% and that for TVR was 7.65%. This preliminary study provides enough clinical evidence that implantation of intracoronary bare metal stents coated with diamond-like carbon is associated with high success rates, safety, and efficacy, both in the hospital and at the 6-month follow-up after the interventional procedure.