Periodontal tissue engineering by hPDLF seeding on scaffold / 대한치주과학회지

Human periodontal ligament fibroblasts (hPDLF) are very important for curing the periodontal tissue because they can be differentiated into various cells. A tissue engineering approach using a cell-scaffold is essential for comprehending today's periodontal tissue regeneration procedure. This study examined the possibility of using an acellular dermal matrix as a scaffold for human periodontal ligament fibroblast (hPDLF). The hPDLF was isolated from the middle third of the root of periodontally healthy teeth extracted for orthodontic reasons. The cells were cultured in a medium containing Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum at 37degrees C in humidified air with 5% CO2. The acellular dermal matrix(ADM) was provided by the US tissue banks(USA). Second passage cells were used in this study. The hPDLF cells were cultured with the acellular dermal matrix for 2 days, and the dermal matrix cultured by the hPDLF was transferred to a new petri dish and used as the experimental group. The control group was cultured without the acellular dermal matrix. The control and experimental cells were cultured for six weeks. The hPDLF cultured on the acellular dermal matrix was observed by Transmission Electron microscopy (TEM). Electron micrography shows that the hPDLF was proliferated on the acellular dermal matrix. This study suggests that the acellular dermal matrix can be used as a scaffold for hPDLF.

An Immuno -Electron Microscopic Study for Perlecan in the Synovium of Degenerative Arthritis of Knee / 대한해부학회지

This study was designed to observe the expression of perlecan in the normal and degenerative arthritic synovial membrane. By using the immunohistochemical staining and immuno -electron microscopical gold labeling techniques, we observed five materials of normal and degenerative arthritic synovia each. The results were as follows. 1. By the immunohistochemical methods, perlecan -positive staining was seen on the 1 ~2 cell layers of the normal synovial membrane. But, a weaker staining compared to that seen in the normal synovial membrane was found in the degenerative arthritic synovial membrane. 2. Under the electron microscopic observation, perlecan was largely distributed in the rough endoplasmic reticulum of the secretory synovial cell, and in the vacuoles of the phagocytic synovial cell on the normal synovium of the human knee joint. It was also found in the extracellular matrix of the synovial membrane. 3. Perlecan -positive cells were also identified on the degenerative arthritic synovium of the human knee joint. However, fewer perlecan was observed here than that found in the normal synovium. In conclusion, perlecan is synthesized by the secretory synovial cells and degraded by the phagocytic synovial cells. And it, known as a major component of the basement membrane, also proven to exist in the extracellular matrix of the synovial membrane having no basement membrane. From the fact that less perlecan was observed in the degenerative arthritis, perlecan is might to play a major role in the degenerative process.

Electronmicroscopic Study of the Effect of Hexamethonium on Serous Choriretinopathy in Rabbits

Stress has been regrarded as one of the causes of central serous chorioretinopathy. We studied the effect of Hexamethonium (ganglionic blocking agent) on experimentaI serous chorioretinopathy following epinephrine injection in rabbits. In group 1, we injected the 0.1 % epinephrine into the rabbits through IV route for 10 days and in group 2, we addited Hexamethonium subcutaneously prior to injection of the epinephrine same term of gorup 1. We could find slight histological changes in gorup 2 as com paired with group 1, which produced serous chorioretinopathy, under the electronmicroscopic study so we would expect the preventive effect of Hexamethonium on the stress-induced serous chorioretinopathy.

Electronmicroscopic Study of the Effect of Hexamethonium on Serous Choriretinopathy in Rabbits

Stress has been regrarded as one of the causes of central serous chorioretinopathy. We studied the effect of Hexamethonium (ganglionic blocking agent) on experimentaI serous chorioretinopathy following epinephrine injection in rabbits. In group 1, we injected the 0.1 % epinephrine into the rabbits through IV route for 10 days and in group 2, we addited Hexamethonium subcutaneously prior to injection of the epinephrine same term of gorup 1. We could find slight histological changes in gorup 2 as com paired with group 1, which produced serous chorioretinopathy, under the electronmicroscopic study so we would expect the preventive effect of Hexamethonium on the stress-induced serous chorioretinopathy.

The Effect of Thyrotropin Releasing Hormone on the Somatosensory Evoked Potentials and the Ultrastructure of Myelinated Nerve Fibers in Injuried Spinal Cord

The purpose of this study was to determine the effect of treatment with thyrotropin releasing hormone(TRH) on the somatosensory evoked potentials(SSEPs) and ultrastructures of myelinated nerve fibers in injured spinal cords. Spinal cords of cats were injured expermentally at the second lumbar vertebra level with 20gm-20cm(400gm-cm) impact force using modified Allen's weight drop method. The animals were treated with TRH(2mg/Kg, bolus, then 2mg/Kg/hour, IV, for 4 hours) 1 hour after injury. SSEPs were checked serially in both treated and untreated groups for 24 hours. And the fine strucures of myelinated nerve fibers in the white matters were observed in electronmicroscope before and after the injury in both groups. In treated groups, the inital positive waves were re-elicited 3 hours after injury which was eliminated immediately after injury. Fine structure of the myelinated nerve fibers were changed progressively. With time after injury, the myelinated nerve fibers showed enlarged periaxonal spaces, irregulary contoured axons, and disarray of myelin sheaths. By 4 hours after injury, there appeared marked separation and disrray of myelin sheaths, and mitochondria and neurofibrils in axoplasm showed serve degeneration. The result of this study suggested that TRH has a beneficial effect on the re-elicitation of SSEP's and the preservation of myelinated nerve fibers in the acute stage of spinal cord injury.

The Study of the Interfaces between Compound Bioceramics Artificial Bone and Bone By Means of Scanning Electron Microscope and X-ray Energy Spectrum Analysis / 昆明医科大学学报

The Compound Bioceramic (CBC),a newly developed artificial bone material,were im- planted in the man-made defects on madibular bodies of four dogs.The an imals were sacri- ficed three months later.The specimens were prepared by routine procedures.The interfaces between the CBC materials and bones were studied by electromicroscope scanning and X-ray energy spectrum analysis:the results showed that the CBC materials could be bioconnected with bones (osseous bond as was called).The study suggested that the osseous bond mecha- nism of the CBC material be related to the ion migration and deposition of calcium and phosphate on the interfaces.

MICROANATOMY AND SEM OBSERVATIONS OF INTRACEREBRAL VESSELS / 解剖学报

Intracerebral vessels from 10 hemispheres of children were perfused with ABS and observed under the 6212-Ⅲ surgical microscope and TSM-Ⅰ scanning electron microscope.1. The arterial network of the pia mater shows irregular anastomoses. Many terminal branches in the meshwork do not form anastomosis but perforate into the brain tissue at right angle. Most of the points where the arteries perforate are longit udinally arranged along the gyri.2. The venous network of the pia mater usually lies deeper than the arteries and becomes superficial to the latter after joining together to form larger vessels.3. The cortical arteries have an average diameter of 44.3?m. They are densely distributed like hairs of a brush.4. The tributaries of the cortical veins join to form larger veins assuming the shape of an inverted fir tree.5. The medullary arteries are different in length and in diameter. The diameter averages 158.2?m. The arteries perforating through the top of the gyrus are straight but those from the sulcus bend to a certain degree after they pass through the cortex. Branches from the middle segments come out vertically and form "T"-shape branches. The deep segments send out branches like the roots of a tree and form widespread anastomoses with the central arteries. Wavy, tortuous medullary arteries can be also found. The casts of these arteries were observed under the SEM.The medullary veins and central arteries have been studied and described microanatomically.

EFFECT OF ULTRASONICALLY ACTIVATED HEMATOPORPHYRIN ON EHRLICH ASCITES TUMOR CELLS IN VITRO / 解剖学报

Objective The aim of this study was to investigate the effect of ultrasonically activated hematoporphyrin on ultrastructure of ehrlich ascites tumor(EAT) cells and to evaluate the potential mechanism of action inducing this cytotoxicity. Methods EAT cells in vitro were exposed to ultrasound at 2