Tsuyoshi Soji

Experimental retinal tolerance to emulsified silicone oil.

Vitreous replacement by silicone oil has become increasingly popular in the treatment of severe and complicated retinal detachment. Several studies have suggested that silicone oil may be toxic to the retina or may stimulate periretinal proliferation. To better understand its effects, emulsified or nonemulsified silicone oil was injected into rabbit eyes that had undergone mechanical vitrectomy. Silicone oil was labeled with phthalocyanine blue to aid in histologic localization. Retinal changes were compared by light microscopy at 1, 4, and 12 weeks after intraocular injection. Emulsified silicone oil was found to penetrate the inner retina at 1 week and cause epiretinal membrane formation as early as 4 weeks after injection. Nonemulsified oil produced no histologic changes in the retina. No cytotoxic effects were observed in eyes treated with ether emulsified or nonemulsified silicone oil. It is concluded that emulsified silicone oil can both penetrate the retina and stimulate epiretinal membrane formation in the vitrectomized rabbit eye.

Evidence that C4b-binding protein (proline-rich protein) is synthesized by hepatocytes

C4b-binding protein (C4bp), a glycoprotein involved in regulating the classical pathway of the complement system, binds the activated form of C4b and accelerates the decay rate of the C4b, C2a complex. Recently, sequence analysis of the cDNA for proline-rich protein (PRP) demonstrated that PRP is identical with C4bp. We measured the concentration of C4bp in serum by single radial immunodiffusion in patients with various liver diseases. Concentration of C4bp was significantly lower in hepatic cirrhosis (P = 0.001) and higher in fatty liver (P = 0.0002) than the control values, after adjusting for age, sex, and concentration of total cholesterol, triglyceride, and C-reactive protein. Significant positive correlations were observed between the concentration of C4bp in serum and total protein, albumin, cholinesterase level, and lecithin-cholesterol acyltransferase activity. Immunohistochemical analysis of human liver with specific antiserum to human C4bp demonstrated reaction endproducts in the hepatocytes around the central veins. These observations provide evidence that C4bp is synthesized by hepatocytes.

Morphological characteristics of the deep layer of articularis genus muscle

BACKGROUND The articularis genus muscle pulls the suprapatellar pouch upwards when the knee joint is extended, preventing mechanical impingement of the joint capsule which theoretically could cause anterior knee pain. However, few anatomical studies have addressed this muscle. Here we present the precise morphology of articularis genus. MATERIALS AND METHODS A total of 22 (13 male and 9 female) adult cadavers with no pathological conditions in the knee joints were examined during educational dissection at Nagoya City University Medical School in 2012. After exclusion of 4 joints due to their flexion contracture, 40 knee joints (18 right and 22 left) were analysed. We performed statistical analysis on anatomical laterality and the difference of sizes among lateral, medial and central branches and studied the correlation of the length and area of the articularis genus muscle to the lengthand cross-section area of the femur. RESULTS AND CONCLUSIONS The average number of branches of the deep layer of the articularis genus muscle was 2.7 ± 0.5, the mean length of all brancheswas 5.4 ± 1.3 cm and the mean area of all branches was 5.5 ± 2.6 cm². There was no significant correlation between the length and area of the articularis genus muscle to the length and cross-section area of the femur. There was no significant laterality in central, medial and lateral branches; however we found that the medial branch was statistically longer and larger than the lateral branchon either knee. This could be contributing to prevention of lateral dislocation of the patella.