The purpose of this study is to evaluate the critical maintenance period of absorbable membrane for guided bone regeneration. Fortynine Sprague-Dawley rats weighing about 300g were divided into seven groups. An 8 mm circular full-thickness defect in calvarial bone was made and then cellular acetate porous filter (Millipore filter(R)) was placed on the calvarial bone defect. The filter was removed at 2, 3, 4, 5, 6, 8 and 11 weeks after placement. Rats were sacrificed at 12 weeks the placement of cellular acetate porous filter. The specimens were stained with Hematoxylin-Eosin and observed under light microscope. The amount of regenerated bone was measured from both margin of calvarial bone defect (unit : mm). The results were as follows. Bone regeneration of each experimental group was increased gradually and the bond defect was almost completely filled with new bone in 5-, 6-, 8-, and 11-week experimental group. Histologic findings showed mild inflammatory response and granulation tissue formation without apparent adverse effects on the healing process. In 11-week experimental group, the bone defect was completely filled with new bone containing abundant osteoid which was oriented to the dural side and contribute to bony thickening. We suggest that non-absorbable membrane and bioabsorbable membrane presumably should remain intact for longer than 5 weeks to be effective.
Animals ; Bone Regeneration ; Granulation Tissue ; Membranes* ; Micropore Filters* ; Rats* ; Rats, Sprague-Dawley

An experimental study was done to evaluate factors influencing guided regeneration of bone in standardized calvarial bony defect. An 8 mm circular transosseous calvarial bony defect was made. Various material such as demineralized freeze-dried bone (DFDB), BioMesh , Millipore filter and its combination was placed in the bony defect. A sequential histopathologic, histochemical, immunohistochemical, and histomorphometric studies were done on the guided bone regeneration in the calvarial bony defect. Bone formation was sigificantly enhanced when the DFDB was retained within the bony defect with a protective bioabsorbable membrane. Inframembranous DFDB-filling was required to prevent collapse of the membrane and preserve spaces for bone regeneration. The bioabsorbable membrane should presumably remain intact for longer than at least 5 weeks to facilitate bone regeneration. The new bone formation was dependent on the barrier-effect (preserving secluded spaces) and inflammation-inducing property of membrane, and guiding bone regeneration of the grafts. Macrophages recruited by grafts were partly involved in decrease of bone regeneration via the sequential events of release of fibronectin, chemotactic effect of the fibronectin to fibroblasts, and collagen lay-down.
Animals ; Bone Regeneration ; Collagen ; Fibroblasts ; Fibronectins ; Macrophages ; Membranes ; Micropore Filters ; Osteogenesis ; Rats* ; Regeneration* ; Transplants

PURPOSE: To evaluate 0.025% brilliant blue G (BBG) for staining the internal limiting membrane (ILM) during vitrectomy. METHODS: In a retrospective, non-comparative clinical case series, we analyzed consecutive 111 patients who underwent pars plana vitrectomy and removal of the ILM after staining using BBG solution. BBG was dissolved and diluted with balanced salt solution at a concentration of 0.025% and then sterilized by filtering through a 0.22 microm millipore filter. The prepared BBG solution was injected into the vitreous cavity over the macula after removal of the vitreous and excessive solution was removed immediately. RESULTS: The ILM was successfully removed without use of additional adjuvant in all cases. Mean best corrected visual acuity (log MAR) was significantly improved from 0.80 +/- 0.44 at baseline to 0.40 +/- 0.39 at 6 months postoperatively (p < 0.001). One case each of endophthalmitis and diabetic papillopathy developed. The relationship when using BBG solution was not identified as complications were not observed in the other patients who underwent vitrectomy using the same BBG solution on the same day. One idiopathic epiretinal membrane patient had visual acuity loss more than 2 lines. During the follow-up period, other complications suspected to be associated with the use of BBG solution were not observed. CONCLUSIONS: A BBG solution (0.025%) was effective in staining the ILM for removal. Complications associated with the use of BBG solution were not observed.
Endophthalmitis ; Epiretinal Membrane ; Follow-Up Studies ; Humans ; Membranes* ; Micropore Filters ; Retrospective Studies ; Visual Acuity ; Vitrectomy*

PURPOSE: To evaluate 0.025% brilliant blue G (BBG) for staining the internal limiting membrane (ILM) during vitrectomy. METHODS: In a retrospective, non-comparative clinical case series, we analyzed consecutive 111 patients who underwent pars plana vitrectomy and removal of the ILM after staining using BBG solution. BBG was dissolved and diluted with balanced salt solution at a concentration of 0.025% and then sterilized by filtering through a 0.22 microm millipore filter. The prepared BBG solution was injected into the vitreous cavity over the macula after removal of the vitreous and excessive solution was removed immediately. RESULTS: The ILM was successfully removed without use of additional adjuvant in all cases. Mean best corrected visual acuity (log MAR) was significantly improved from 0.80 +/- 0.44 at baseline to 0.40 +/- 0.39 at 6 months postoperatively (p < 0.001). One case each of endophthalmitis and diabetic papillopathy developed. The relationship when using BBG solution was not identified as complications were not observed in the other patients who underwent vitrectomy using the same BBG solution on the same day. One idiopathic epiretinal membrane patient had visual acuity loss more than 2 lines. During the follow-up period, other complications suspected to be associated with the use of BBG solution were not observed. CONCLUSIONS: A BBG solution (0.025%) was effective in staining the ILM for removal. Complications associated with the use of BBG solution were not observed.
Endophthalmitis ; Epiretinal Membrane ; Follow-Up Studies ; Humans ; Membranes* ; Micropore Filters ; Retrospective Studies ; Visual Acuity ; Vitrectomy*

The membrane separation is a new practical technique with wide applications. This paper introduces the course of its development, theorem and feature, and the usage of its module. Its application in the research and production is reviewed. Its existent questions in the applications presently are analyzed and the relevant resolvents are brought forward.
Filtration ; instrumentation ; methods ; Hemofiltration ; instrumentation ; Micropore Filters ; Technology, Pharmaceutical ; instrumentation ; methods ; Ultrafiltration ; instrumentation ; methods

Anti-Bacterial Agents ; Copper ; Disinfection ; Ethylene Oxide ; Fibroblasts ; Freezing ; Micropore Filters ; Sterilization ; Succinate Dehydrogenase ; Transplants

Fat embolism is a condition in which fat appears in the circulating blood, not in the fine emulsion of a metabolic lipemia, but in droplets large enough to occlude arterioles and capillaries. It may occur as a complication of fracture, particularly multiple fractures of the long bones, pelvis, and ribs.. Since Zenker described the first case of fat embolism in 1862 there has never been a reliable diagnostic test for this condition. Lipid changes in the blood and demonstration of macroglobules could be used as aids for early post- traumatic fat embolism syndrome. The purpose of the present,study was to analyze the blood lipid changes in the fracture and to determine their value in the early detection of fat embolism syndrome. Twenty-three patients with at least one diaphyseal fracture of the lower extremity or a pelvic and spine fracture were included in the study. The mean age of the patients was 30.3 years. Men outnumbered women by a ratio of 2.9:1. Nineteen of the patients were injured in traffic accidents, two patients in fall, and one in the industrial accident. Ten volunteers were used for the control studies, nine men and one woman. Their mean age was 22.8 years. For determination of blood lipids blood sample was taken from cubital vein. The flrst blood sample was taken from tbe patients less than 2 hours after the iniury, and the later samples were obtained respectively in 12, 24, 48 and 72 hours, and 7 days after injury. The samples were centrifuged immediately (2,500 rpm, 4 min.). After centrifugation, each sample of plasma or serum was divided into two aliquots. The one aliquot was studied without flltering and the other was filtered through 8 microns millipore filter (Watmann No. 40. filter paper). Determination of triglyceride, cholesterol, and phospsolipids in blood was made from the unfiltered aliquot and from the other filtrate. Two groups were formed for comparission of the results; 1) Fracture Group; 2) Non-fracture Group as control. The triglycerides was determined using the technic of the micromethod of Van Handel and Elversmith, and the cholesterol was determined by the technic of Rosenthals color reagent method. For the determination of phospholipids Youngburg, modified method was used of The results of the study lead us to conclude that: 1. The triglycerides, cholesterol, phosphollpids fractions in the unflltered allquot was slightly higher than those of the filtrate. 2. Less than two hours after injury the triglycerides concentration in blood of fracture group was similar to the concentrations of the controls. But the triglycerides and macroglobule concentration in 12 and 24 hours after fracture were higher than those of the control group. 3. The average concentration of blood cholesterol level in fracture group was slightly higher than the control. Especially the serum concentrations of cholesterol in 12, and 24 hours after fracture were much higher than those of the controls. Statistically significant differences between the groups were observed. 4. The average phospholipids concentration in fracture patients was slightly higher than the average phospholipids concentration of the control but no significant differences between the groups were observed. 5. As to the total lipids, the average concentration of fracture group was little bit higher than the concentration of the control. There was no statistical differences between the fracture and the control group. 6. The concentrations of the total lipids gradually increased after 40 years of age. 7. The concentration of total serum lipids was increased in femoral fracture in site, and in multiple fractures than single fracture.
Accidents, Occupational ; Accidents, Traffic ; Arterioles ; Capillaries ; Centrifugation ; Cholesterol ; Diagnostic Tests, Routine ; Embolism, Fat ; Female ; Femoral Fractures ; Fractures, Multiple ; Humans ; Hyperlipidemias ; Lower Extremity ; Male ; Methods ; Micropore Filters ; Pelvis ; Phospholipids ; Plasma ; Ribs ; Spine ; Triglycerides ; Veins ; Volunteers

In order to study the effect of ascorbic acid on the growth of the fetal rat long bones in calcium free culture medium, fetal femurs from rat fetus on 19th day of gestation were cultured for 1, 3, 5, 7 and 9 days in medium described below. Culture media used were MEM, Ca++
Animals ; Ascorbic Acid ; Bone and Bones ; Bone Marrow ; Bone Matrix ; Calcium ; Cartilage ; Chondrocytes ; Collagen ; Culture Media ; Cytoplasm ; Diaphyses ; Epiphyses ; Femur ; Fetus ; Formaldehyde ; Glutaral ; Methods ; Micropore Filters ; Microscopy ; Microscopy, Electron ; Osmium ; Periosteum ; Pregnancy ; Rats ; Stainless Steel

OBJECTIVETo observe the ability of SD rat dental papillae cells forming dentin-like structure induced by millipore filter combined with transforming growth factor-β(1) (TGF-β(1)).

METHODSThe first passage SD rat dental papillae cells were enzymatically dissociated and centrifuged to obtain a cell mass. The cell mass was seeded on the millipore filter combined with TGF-β(1). The complex was incubated for 6 d in vitro or transplanted under the renal capsule for 2 weeks. Then the differentiation of dental papillae cells on the filter and the formation of mineral tissue on the implant were analyzed.

RESULTSA layer of polarized columnar cells were observed along the surface of the millipore filter, with cell processes extending into the porous media. Dentin sialoprotein (DSP) and dentin matrix protein-1 (DMP-1) were positive in these cells. After 2 weeks, tubular dentin matrix was deposited on the surface of the aligned cells. Scanning electron microscopy showed that the thickness of newly formed tubular dentin was consistent. DSP and DMP-1 were expressed in columnar cells, tubular matrix and the dental papillae cells adjacent to the filter.

CONCLUSIONSThe millipore filter combined with TGF-β(1) could effectively recruit progenitors onto its surface and induce odontoblast differentiation, secrete matrix in a homogenous manner, leading to dentinogenesis.

Animals ; Cell Differentiation ; Cells, Cultured ; Dental Papilla ; cytology ; Dentin ; Dentinogenesis ; Extracellular Matrix ; Extracellular Matrix Proteins ; Micropore Filters ; Odontoblasts ; Phosphoproteins ; Rats ; Sialoglycoproteins ; Tissue Engineering ; Transforming Growth Factor beta ; Transforming Growth Factor beta1 ; pharmacology

PURPOSE OF STUDY: Peripheral nerve regeneration depends on neurotrophism of distal nerve stump, recovery potential of neuron, supporting cell like Schwann cell and neurotrophic factors such as BDNF. Peripheral nerve regeneration can be enhanced by the conduit which connects the both sides of transected nerve. The conduit maintains the effects of neurotrophism and BDNF produced by Schwann cells which can be made by gene therapy. In this study, we tried to enhance the peripheral nerve regeneration by using calcium phosphate coated porous conduit and BDNF-Adenovirus infected Schwann cells in sciatic nerve of rats. MATERIALS AND METHODS: Microporous filter which permits the tissue fluid essential for nerve regeneration and does not permit infiltration of fibroblasts, was made into 2mm diameter and 17mm length conduit. Then it was coated with calcium phosphate to improve the Schwann cell adhesion and survival. The coated filter was evaluated by SEM examination and MTT assay. For effective allogenic Schwann cell culture, dorsal root ganglia of 1-day old rat were extracted and treated with enzyme and antimitotic Ara-C. Human BDNF cDNA was obtained from cDNA library and amplified using PCR. BDNF gene was inserted into adenovirus shuttle vector pAACCMVpARS in which E1 was deleted. We infected the BDNF-Ad into 293 human mammary kidney cell-line and obtained the virus plaque 2 days later. RT-PCR was performed to evaluate the secretion of BDNF in infected Schwann cells. To determine the most optimal m.o.i of BDNF-Ad, we infected the Schwann cells with LacZ adenovirus in 1, 20, 50, 75, 100, 250 m.o.i for 2 hours and stained with beta-galactosidase. Rats(n=24) weighing around 300g were used. Total 14mm sciatic nerve defect was made and connected with calcium phosphate coated conduits. Schwann cells(1x10(6)) or BDNF-Ad infected Schwann cells(1x10(6)) were injected in conduit and only media(MEM) was injected in control group. Twelve weeks after surgery, degree of nerve regeneration was evaluated with gait analysis, electrophysiologic measurements and histomorphometric analysis. RESULTS: 1. Microporous Millipore filter was effective conduit which permitted the adhesion of Schwann cells and inhibited the adhesion of fibroblast. We could enhance the Schwann cell adhesion and survival by coating Millipore filter with calcium phosphate. 2. Schwann cell culture technique using repeated treatment of Ara-C and GDNF was established. The mean number of Schwann cells obtained 1 and 2 weeks after the culture were 1.54+/-4.0*10(6) and 9.66+/-9.6*10(6). 3. The mRNA of BDNF in BDNF-Ad infected Schwann cells was detected using RT-PCR. In Schwann cell 0.69 microgram/microliter of DNA was detected and in BDNF-Adenovirus transfected Schwann cell 0.795 microgram/microliter of DNA was detected. The most effective infection concentration was determined by LacZ Adenovirus and 75 m.o.i was found the most optimal. CONCLUSION: BDNF-Ad transfected Schwann cells successfully regenerated the 14mm nerve gap which was connected with calcium phosphate coated Millipore filter. The BDNF-Ad group showed better results compared with Schwann cells only group and control group in aspect to sciatic function index, electrophysiologic measurements and histomorphometric analysis.
Adenoviridae ; Animals ; beta-Galactosidase ; Brain-Derived Neurotrophic Factor* ; Calcium* ; Cell Adhesion ; Cell Culture Techniques ; Cytarabine ; DNA ; DNA, Complementary ; Fibroblasts ; Gait ; Ganglia, Spinal ; Gene Library ; Genetic Therapy ; Genetic Vectors ; Glial Cell Line-Derived Neurotrophic Factor ; Humans ; Kidney ; Micropore Filters ; Nerve Growth Factors ; Nerve Regeneration ; Neurons ; Peripheral Nerves ; Polymerase Chain Reaction ; Rats* ; Regeneration* ; RNA, Messenger ; Schwann Cells ; Sciatic Nerve*