Deposits on soft contact lenses of high water content were investigated morphologically and chemically and compared with those on conventional soft contact lenses of poly (2-hydroxyethyl methacrylate). The material of the lenses examined in this investigation was the crosslinked copolymer of methyl methacrylate and N-vinylpyrrolidone with a water content higher than 70%. Morphologically, the deposits on the lenses with high water content were found to have no characteristics distinguishable from those on conventional lenses. By the electron microscopic observation of the cross section of a lens that had become opaque, it was confirmed that the deposit was on the lens surface and that no deposit was within the lens. Some spots on the lenses were recognized as colonies of microorganisms, but the majority of the spots had no involvement by microorganisms. Surface analysis with Fourier transform infrared spectrometer (FT-IR) confirmed that the main component of the filmy deposit was protein. Protein was detected in most of the deposits. The amino acid compositions of the proteins were found to be close to that of lysozyme. From the elemental analysis of several spots, silicon, aluminum, iron, and some other elements were detected. The structural analysis of some spots by a laser Raman microprobe (MOLE) revealed the existence of lipids. In several cases, the deposits were found to have grown around a defect of the lens surface. A mechanism for the formation of deposits is suggested.
The mechanical properties of the hydrogel membrane of poly(methyl methacrylate-N-vinylpyrrolidone) were studied for the purpose of making soft contact lenses for extended wear. The dependence of tensile fracture energy, flexibility, and recovery from deformation on the water content and thickness of the hydrogel membrane was studied. Reducing the thickness of a lens was found to exert a more advantageous effect than increasing its water content on maximizing the tensile fracture energy under the condition of an adequate supply of oxygen to the cornea through the contact lens. As long as its water content is controlled between 63 and 78%, the contact lens made of poly(methyl methacrylate-N-vinylpyrrolidone) has the flexibility on the same order as that of conventional soft contact lenses of poly(2-hydroxyethyl methacrylate). The rate of recovery from deformation increases with water content, and the residual elongation is negligible in the range of water content over about 70%. It is concluded that practical requirements for use of these contact lenses, determined by these three mechanical properties, can be satisfied at the same time if the water content of the contact lens is adjusted at about 70%.
Normalization of serum ALT levels after interferon therapy led to a histological improvement, and that with viral clearance achieved histological cure. Serum fibrosis markers were useful indicators for long-term according to the response of IFN therapy.
In order to detect herpes virus group DNA including that of the Epstein-Barr virus (EBV) in patients with Vogt-Koyanagi-Harada disease (VKH), the authors employed the polymerase chain reaction (PCR) procedure using DNA from cerebrospinal fluid (CSF) obtained from patients with VKH. Method. Seven CSF samples were obtained from six definite, active VKH cases and DNA was isolated. DNA fragments containing parts of herpes simplex virus (HSV), herpes zoster virus (VZV), cytomegalo virus (CMV), EBV and human herpes virus type 6 (HHV-6) sequences were amplified by PCR. Results. No DNA fragment corresponding to the DNA sequence of the herpes virus group was detected. Conclusion. Our results suggest that the herpes virus group does not have a close association with the cause of VKH.
A case of metastatic pheochromocytoma of the reconstruction of the shoulder joint is reported. During the operation elevation of the blood pressure was controlled by venous injection of alpha-blocker and ligation of the three main feeder arteries and veins.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.