The Influences of Different Ratios of Biphasic Calcium Phosphate and Collagen Augmentation on Posterior Lumbar Spinal Fusion in Rat Model

PURPOSE: To determine the influence of different ratios of hydroxyapatite (HA)/beta tricalcium phosphate (β-TCP) and collagen augmentation for posterior lumbar fusion in a rat model. MATERIALS AND METHODS: We generated a posterior lumbar fusion model in 50 rats and divided it into five groups of equal number as follows; 1) autologous bone graft as group A, 2) 70% HA+30% β-TCP as group B, 3) 70% HA+30% β-TCP+collagen as group C, 4) 30% HA+70% β-TCP as group D, and 5) 30% HA+70% β-TCP+collagen as group E. Rats were euthanized at 12 weeks after surgery and fusion was assessed by manual palpation, quantitative analysis using microCT and histology. RESULTS: The score of manual palpation was significantly higher in group C than group E (3.1±1.1 vs. 1.8±0.8, p=0.033). However, in terms of microCT analysis, group D showed significantly higher scores than group B (5.5±0.8 vs. 3.1±1.1, p=0.021). According to quantitative volumetric analysis, 30% HA+70% β-TCP groups (group D and E) showed significantly reduced fusion mass at 12 weeks after surgery (123±14.2, 117±46.3 vs. 151±27.3, p=0.008, 0.003, respectively). Collagen augmentation groups revealed superior results in terms of both microCT score and histologic grade. CONCLUSION: A 7:3 HA/β-TCP ratio with collagen augmentation rather than a 3:7 HA/β-TCP ratio could be a more favorable graft substitute for lumbar spinal fusion. There was positive role of collagen as an adjunct for spinal bone fusion process.

Optimization of the optical transparency of rodent tissues by modified PACT-based passive clearing

Recently, a bio-electrochemical technique known as CLARITY was reported for three-dimensional phenotype mapping within transparent tissues, allowing clearer whole-body and organ visualization with CB-perfusion (CUBIC) and leading to the development of whole-body clearing and transparency of intact tissues with the PACT (passive clarity technique) and PARS (perfusion-assisted agent release in situ) methodologies. We evaluated the structure–function relationships in circuits of the whole central nervous system (CNS) and various internal organs using improved methods with optimized passive clarity. Thus, in the present study, we aimed to improve the original PACT procedure and passive clearing protocols for different intact rodent tissues. We determined the optimal conditions for the passive clarity method that allowed the production of a transparent whole CNS by clearing the brain and spinal cord, as well as various organs. We also improved the tissue transparency using mPACT (modified PACT), a method for direct passive clearing, and whole perfusion-based PARS-mPACT, a method for fusion clearing, and we identified the appropriate experimental conditions. These optimized methods can be used for easy and economical high-resolution mapping and phenotyping of normal and pathological elements within intact tissues.

Improvement Characteristics of Bio-active Materials Coated Fabric on Rat Muscular Mitochondria

This study surveys the improvement characteristics in old-aged muscular mitochondria by bio-active materials coated fabric (BMCF). To observe the effects, the fabric (10 and 30%) was worn to old-aged rat then the oxygen consumption efficiency and copy numbers of mitochondria, and mRNA expression of apoptosis- and mitophagy-related genes were verified. By wearing the BMCF, the oxidative respiration significantly increased when using the 30% materials coated fabric. The mitochondrial DNA copy number significantly decreased and subsequently recovered in a dose-dependent manner. The respiratory control ratio to mitochondrial DNA copy number showed a dose-dependent increment. As times passed, Bax, caspase 9, PGC-1alpha and beta-actin increased, and Bcl-2 decreased in a dose-dependent manner. However, the BMCF can be seen to have had no effect on Fas receptor. PINK1 expression did not change considerably and was inclined to decrease in control group, but the expression was down-regulated then subsequently increased with the use of the BMCF in a dose-dependent manner. Caspase 3 increased and subsequently decreased in a dose-dependent manner. These results suggest that the BMCF invigorates mitophagy and improves mitochondrial oxidative respiration in skeletal muscle, and in early stage of apoptosis induced by the BMCF is not related to extrinsic death-receptor mediated but mitochondria-mediated signaling pathway.

Nestin expressing progenitor cells during establishment of the neural retina and its vasculature / 대한해부학회지

In order to test if nestin is a useful marker for various types of progenitor cells, we explored nestin expression in the retina during development. Nestin expression was co-evaluated with bromodeoxyuridine (BrdU) labeling and Griffonia simplicifolia isolectin B4 (GSIB4) histochemistry. Nestin immunoreactivity appears in cell soma of dividing neural progenitor cells and their leading processes in retinas from embryonic day (E) 13 to E20, in accordance with a BrdU-labeled pattern. At postnatal day (P) 5, it is restricted to the end feet of Muller cells. BrdU-labeled nuclei were mainly in the inner part of the inner nuclear layer in postnatal neonates. The retinal vessels demarcated with GSIB4-positive endothelial cells were first distributed in the nerve fiber layer from P3. Afterward the vascular branches sprouted and penetrated deeply into the retina. The endothelial cells positive for GSIB4 and the pericytes in the microvessels were additionally immunoreactive for nestin. Interestingly, the presumed migrating microglial cells showing only GSIB4 reactivity preceded the microvessels throughout the neuroblast layer during vascular sprouting and extension. These findings may suggest that nestin expression represents the proliferation and movement potential of the neural progenitor cells as well as the progenitor cells of the endothelial cell and the pericyte during retinal development. Thus, Muller glial cells might be potential neural progenitor cells of the retina, and the retinal microvasculature established by both the endothelial and the pericyte progenitor cells via vasculogenesis along microglia migrating routes sustains its angiogenic potential.

Pre-synaptic Neuronal Changes of AII Amacrine Cells in the Streptozotocin-induced Diabetic Rat Retina / 대한해부학회지

It has been previously reported that parvalbumin expression was downregulated in AII amacrine cells, while upregulated in a subset of cone bipolar cells electrically synapse with AII amacrine cell in the streptozotocin-induced diabetic rat retina. In the present study, we aimed to trace biochemical changes of pre-synaptic neurons to AII amacrine cells in rat retina following diabetic injury. Diabetic condition was induced by streptozotocin injection into Sprague-Dawley rats aged of 8 weeks. The experimental term of induced diabetes was set at 1, 4, 12 and 24 weeks. Changes of pre-synaptic neurons were evaluated by immunohistochemistry and Western blot analysis with anti-protein kinase C (PKC)-alpha and anti-tyrosine hydroxylase (TH) antibodies. Rod bipolar cells immunolocalized with PKC-alpha antibody extended their enlarged axon terminals into stratum 5 of the inner plexiform layer. In later diabetes, the axon was shorten and its terminals of rod bipolar cell are slightly enlarged. The protein levels of PKC-alpha were slightly increased along with the duration of diabetes. TH immunoreactive neurons are morphologically classified into two subtypes of amacrine cells in the inner nuclear layer: one (type 1) has large soma with long and primary dendrites, classified with dopaminergic, and the other (type 2) has small soma with dendritic arborization. In the outermost inner plexiform layer, ring-like structures being composed of type 1 cell processes were densely distributed. In diabetic retina, the intensity of TH immunoreactivity in type 1 neurons was reduced. In accordance with morphological changes, the protein levels of TH were reduced during diabetes. These results demonstrate that TH immunoreactive dopaminergic amacrine cells are more susceptible to diabetic injury than the rod bipolar cells in the rat retina and may suggest that downregulation of parvalbumin expression in AII amacrine cells of diabetic retina is mainly due to dysfunction of pre-synaptic dopaminergic amacrine cells.

Altered Expression of Parvalbumin in Neural Retina of the Insulin-dependent Diabetic Rat / 대한해부학회지

Calcium-binding proteins in the nervous system are functioned in Ca2+ buffering and Ca2+ transport and regulation of various enzyme systems. They potentially have a number of different effects on cells includingaltering the duration of action potentials, promoting neuronal bursting activity and protecting cells against the damaging effects of excessive calcium influx. The present study has been designed to clarify the differential responding patterns of parvalbumin immunoreactive neurons in the rat retina following diabetic injury, for better understandings of role of parvalbumin in the retinal circuitry and in calcium homeostasis. Experimental diabetes was induced by a single intravenous injection of streptozotocin in a dose of 60 mg/kg body weight. Diabetic rats showing high blood glucose levels (above 300 mg/dL) were cared for 1, 4, 8, 12 and 24 weeks, respectively. The retinas at each time point were processed for immunohistochemistry and Western blotting using antiparvalbumin antibody. In the rat retina at normal, parvalbumin immunoreactivity appeared in AII amacrine cells, amacrine cells of a widefield type and displaced amacrine cells. A few bipolar cells are also showed the reactivity. During diabetes, the intensity of parvalbumin immunoreactivity is decreased especially in the AII amacrine cells. The cell number of parvalbumin immunoreactive neurons has showed no large changes throughout the diabetes, except that of bipolar cells. That population of parv immunoreactive of bipolar cells has increased remarkably at later diabetic periods. The protein levels of parvalbumin have showed transiently a slight increase at earlier diabetic periods, and then decreased to lower than that of normal. Parvalbumin immunoreactive bipolar cells at diabetes are co-localized not with PKC-alpha or recoverin, but with glutamate transporter Glt-1b. AII amacrine cell processes were joined with each other and with axon terminals of presumed cone bipolar cells by gap junction. These results suggest that the calcium buffering activity of parvalbumin is shifted from AII amacrine cells to a certain type of cone bipolar cells, in response to diabetes. This event may be occurred through electrically coupled gap junction in between these cell processes.

A Case of Primary Extranodal NK/T Cell Lung Lymphoma Presenting as Multiple Patchy Pulmonary Infiltrations / 결핵

Primary lung lymphoma is an uncommon tumor, which constitutes 0.5% of primary lung cancer, and 3% of extranodal lymphoma. The most frequent radiologic presentation of pulmonary parenchymal lymphoma is single mass or nodule. But we have experienced a case which was radiologically presented as patchy lung infiltration at first, and then progressive multiple reticulonodular infiltrations in lung. A 48-year-old woman was admitted to the hospital because of fever and cough. Chest PA obtained on admission revealed multiple patchy infiltration. Eventually, open lung biopsy was performed and the specimen disclosed extranodal NK/T cell lymphoma, and in bone marrow aspiration, hemophagocytosis was present. We report a case of primary extranodal NK/T cell lung lymphoma presented as patchy lung infiltrations, which was treated with chemotherapy.

Clinicopathologic Significance of Multidrug Resistance Protein Expression in Patients with Stage III Gastric Adendegrees Carcinoma / 대한암학회지

PURPOSE: We wanted to determine the prognostic significance of P-glycoprotein (Pgp) and multi drug resistance-assdegrees Ciated protein (MRP) in stage III gastric adendegrees Carcinoma by evaluating whe ther the Pgp and/or MRP expression correlate with various clinicopathological parameters and survival rates. MATERIAL AND METHODS: The expression of Pgp and/or MRP were studied immunohistdegrees Chemi cally by ABC method with paraffin-embedded tissue specimens which were surgically obtained from 64 cases of stage III gastric adendegrees Carcinomas at the Department of Surgery, Presbyterian Medical Center from 1991 to 1992. Statistical differences of both expression in various factors including survival rates and clinicopatholgical parameters were sought. RESULTS: Expression rates of Pgp and MRP group were 50.0% and 43.7% respectively. There was no significant correlation between expression of two proteins and various clinicopathological variables such as age, sex, stage, tumor depth, number of metastatic node, tumor size, site and method of operation. However, in case of the degree of differenciation, the expression of Pgp and/or MRP was significantly greater in well differenciated adendegrees Carcinoma than in poorly dif ferenciated adendegrees Carcinoma (p=0.001, p=0.012). Statistically, no significant correlations between the expression of Pgp and/or MRP and overall survival rates were found. CONCLUSION: These results suggest that the Pgp and/or MRP expression in patients with stage III gastric adendegrees Carcinomas are not useful in determining postoperative chemotherapy and as an independent predictor of survival.

A Case Arthritis After Intravesical BCG Instillation for Bladder Cancer / 대한류마티스학회지

Intravesical instillation of BCG(Calmette-Guerin Bacillus) is the most widely used treatment of superficial transitional cell carcinoma of the bladder. While the exact mechanisms are not yet known, it is assumed that the recognition of tumor antigen is enhanced by immunologic response of the urothelium of mycobacterium. Various complications have been reported after BCG treatment and arthritis is observed in 0.5 to% of treated patients. This from of arthritis may be attributed to an antigen of mycobacterium sharing a cross reactive epitope with an antigen in articular cartilage. A 40-year-old male had transurethral resection and intravesical instillation of BCG for transitional cell carcinoma of bladder. Within few days of the fourth instillation, he developed arthritis on right knee and right metatarsal joint. Laboratory findings showed nonspecific inflammatory sign, positive HLA B27, negative rheumatoid facor and negative antinuclear antibody. The joint effusion was aseptic. He was treated with nonsteroidal antiinflammatory drugs (indomethacin 200rag/day) with resolution of arthritis symptom. We report a patient who developed an inflammatory oligoarthritis following intravesica] instillation of BCG for the treatment oof bladder cancer.