A Pathophysiological Validation of Collagenase II-Induced Biochemical Osteoarthritis Animal Model in Rabbit

BACKGROUND: Current dilemma working with surgically-induced OA (osteoarthritis) model include inconsistent pathological state due to various influence from surrounding tissues. On the contrary, biochemical induction of OA using collagenase II has several advantageous points in a sense that it does not involve surgery to induce model and the extent of induced cartilage degeneration is almost uniform. However, concerns still exists because biochemical OA model induce abrupt destruction of cartilage tissues through enzymatic digestion in a short period of time, and this might accompany systemic inflammatory response, which is rather a trait of RA (rheumatoid arthritis) than being a trait of OA. METHODS: To clear the concern about the systemic inflammatory response that might be caused by abrupt destruction of cartilage tissue, OA was induced to only one leg of an animal and the other leg was examined to confirm the presence of systemic degenerative effect. RESULTS: Although the cartilage tissues were rapidly degenerated during short period of time upon biochemical induction of OA, they did not accompanied with RA-like process based on the histology data showing degeneration of articular cartilage occurred only in the collagenase-injected knee joint. Scoring evaluation data indicated that the cartilage tissues in non-induced joint remained intact. Neutrophil count transiently increase between day 8 and day 16, and there were no significant change in other complete blood count profile showing a characteristics of OA disease. CONCLUSION: These study shows that biochemically induced cartilage degeneration truly represented uniform and reliable OA state.

Electrodeless conductivity tensor imaging (CTI) using MRI: basic theory and animal experiments

The electrical conductivity is a passive material property primarily determined by concentrations of charge carriers and their mobility. The macroscopic conductivity of a biological tissue at low frequency may exhibit anisotropy related with its structural directionality. When expressed as a tensor and properly quantified, the conductivity tensor can provide diagnostic information of numerous diseases. Imaging conductivity distributions inside the human body requires probing it by externally injecting conduction currents or inducing eddy currents. At low frequency, the Faraday induction is negligible and it has been necessary in most practical cases to inject currents through surface electrodes. Here we report a novel method to reconstruct conductivity tensor images using an MRI scanner without current injection. This electrodeless method of conductivity tensor imaging (CTI) utilizes B1 mapping to recover a high-frequency isotropic conductivity image which is influenced by contents in both extracellular and intracellular spaces. Multi-b diffusion weighted imaging is then utilized to extract the effects of the extracellular space and incorporate its directional structural property. Implementing the novel CTI method in a clinical MRI scanner, we reconstructed in vivo conductivity tensor images of canine brains. Depending on the details of the implementation, it may produce conductivity contrast images for conductivity weighted imaging (CWI). Clinical applications of CTI and CWI may include imaging of tumor, ischemia, inflammation, cirrhosis, and other diseases. CTI can provide patient-specific models for source imaging, transcranial dc stimulation, deep brain stimulation, and electroporation.

Capsanthin Inhibits both Adipogenesis in 3T3-L1 Preadipocytes and Weight Gain in High-Fat Diet-Induced Obese Mice

Adipogenesis in murine preadipocyte 3T3L-1 has been used as a model system to study anti-obese bioactive molecules. During adipogenesis in 3T3-L1 preadipocytes, we found that capsanthin inhibited adipogenesis (IC₅₀; 2.5 μM) and also showed lipolytic activity in differentiated adipocytes from the preadipocytes (ED₅₀ ; 872 nM). We identified that the pharmacological activity of capsanthin on adipogenesis in 3T3-L1 was mainly due to its adrenoceptor-β2-agonistic activity. In high-fat diet animal model study, capsanthin significantly enhanced spontaneous locomotive activities together with progressive weight-loss. The capsanthin-induced activation of kinetic behavior in mice was associated with the excessive production of ATP initiated by both the enhanced lipolytic activity together with accelerated oxidation of fatty acids due to the adrenoceptor β2-agonistic activity of capsanthin. Capsanthin also dose-dependently increased adiponectin and p-AMPK activity in high fat diet animals, suggesting that capsanthin has both anti-obesity and insulin sensitizing activities.

Realistic Electric Field Mapping of Anisotropic Muscle During Electrical Stimulation Using a Combination of Water Diffusion Tensor and Electrical Conductivity / 대한배뇨장애요실금학회지

PURPOSE: To realistically map the electric fields of biological tissues using a diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT) method to estimate tissue response during electrical stimulation. METHODS: Imaging experiments were performed using chunks of bovine muscle. Two silver wire electrodes were positioned inside the muscle tissue for electrical stimulation. Electric pulses were applied with a 100-V amplitude and 100-μs width using a voltage stimulator. During electrical stimulation, we collected DT-MREIT data from a 3T magnetic resonance imaging scanner. We adopted the projected current density method to calculate the electric field. Based on the relation between the water diffusion tensor and the conductivity tensor, we computed the position-dependent scale factor using the measured magnetic flux density data. Then, a final conductivity tensor map was reconstructed using the multiplication of the water diffusion tensor and the scale factor. RESULTS: The current density images from DT-MREIT data represent the internal current flows that exist not only in the electrodes but also in surrounding regions. The reconstructed electric filed map from our anisotropic conductivity tensor with the projected current density shows coverage that is more than 2 times as wide, and higher signals in both the electrodes and surrounding tissues, than the previous isotropic method owing to the consideration of tissue anisotropy. CONCLUSIONS: An electric field map obtained by an anisotropic reconstruction method showed different patterns from the results of the previous isotropic reconstruction method. Since accurate electric field mapping is important to correctly estimate the coverage of the electrical treatment, future studies should include more rigorous validations of the new method through in vivo and in situ experiments.

Application of 3D Surface Scanners in Forensic Science and Medicine ( I ): Digital Storage of Human Skeletons and Development of Appraisal Methods for Incident Scenes / 대한법의학회지

The aim of this project was to use 3D scanning data collected at incident scenes and various evidence to 1) develop surveying methods based on 3D data consisting of overall and detailed scene evidence, captured by long-range and micros-canner, which can be shared by personnel working in different fields such as forensic medicine, video analysis, physical analysis, traffic engineering, and fire investigation; 2) create digital storage for human skeletons and set the foundation for virtual anthropology; and 3) improve the credibility of 3D evidence by virtual remodeling and simulation of incident scenes and evidence to provide a basis for advanced and high-tech scientific investigation. Two complete skeletons of male and female were scanned using 3D micro-scanner. Each bone was successfully reproduced and assembled in virtual space. In addition, recreating evidence scheduled for invasive examination by creating RP (rapid prototype) was possible. These outcomes could play an important role in setting up the new field of virtual anthropology. Case-specific surveying methods were developed through analysis of 3D scanning data collected by long-range surface scanners at the scenes of vehicular accidents, falls, shootings, and violent crimes. A technique and recording method was also developed for detecting forged seals by micro-scanning the pressure exerted on the seal. Appraisal methods developed in this project could be utilized to secure 3D data of human skeletal remains and incident scenes, create a standard for application, and increase objectivity, reproducibility, and accuracy of scanning methods. We plan to develop case-specific 3D data analysis techniques to improve the credibility of analysis at the NFS and to establish a 3D data collection and analysis team.

Growth Status and Body Composition in Children with Central Precocious Puberty and Early Puberty

PURPOSE: The aim of this study was to analyze the growth status and body composition in children with central precocious puberty (CPP ) and early puberty (EP). METHODS: One hundred and five girls (mean age, 7.7 +/- 0.8 years) with early thelarche were included, and a gonadotropin-releasing hormone (GnRH) stimulation test was performed. We divided the subjects into two groups based on peak leuteinizing hormone (LH) levels; peak LH level > or = 5 mIU/L was diagnosed as CPP (n = 49), and peak LH level < 5 mIU/L was diagnosed as EP (n = 56). Patients' height, weight, and body composition were measured, and their body mass index (BMI) and Z-score were calculated. Fat mass (FF), fat-free mass (FFM), fat mass index (FMI), fat-free mass index (FFMI), and percent of body fat (PBF) were compared. RESULTS: Height, weight, and height Z-score were not significantly different between the CPP and EP groups. Weight Z-score (P = 0.045), BMI (P = 0.015), BMI Z-score (P = 0.006), PBF (P = 0.018), FM (P = 0.047), and FMI (P = 0.017) in the EP group were significantly greater than in the CPP group. CONCLUSION: In EP girls, increased BMI was attributed to increased FMI. Body-composition analysis might be a useful tool in monitoring life style modification during pubertal growth.

Growth Status and Body Composition in Children with Central Precocious Puberty and Early Puberty

PURPOSE: The aim of this study was to analyze the growth status and body composition in children with central precocious puberty (CPP ) and early puberty (EP). METHODS: One hundred and five girls (mean age, 7.7 +/- 0.8 years) with early thelarche were included, and a gonadotropin-releasing hormone (GnRH) stimulation test was performed. We divided the subjects into two groups based on peak leuteinizing hormone (LH) levels; peak LH level > or = 5 mIU/L was diagnosed as CPP (n = 49), and peak LH level < 5 mIU/L was diagnosed as EP (n = 56). Patients' height, weight, and body composition were measured, and their body mass index (BMI) and Z-score were calculated. Fat mass (FF), fat-free mass (FFM), fat mass index (FMI), fat-free mass index (FFMI), and percent of body fat (PBF) were compared. RESULTS: Height, weight, and height Z-score were not significantly different between the CPP and EP groups. Weight Z-score (P = 0.045), BMI (P = 0.015), BMI Z-score (P = 0.006), PBF (P = 0.018), FM (P = 0.047), and FMI (P = 0.017) in the EP group were significantly greater than in the CPP group. CONCLUSION: In EP girls, increased BMI was attributed to increased FMI. Body-composition analysis might be a useful tool in monitoring life style modification during pubertal growth.

A Case of Type II Membranoproliferative Glomerulonephritis Detected by School Urinary Screening Tests

Type II membranoproliferative glomerulonephritis (MPGN) is characterized by thickening of the glomerular basement membrane owing to electron-dense deposits on electron microscopy. We experienced a case of type II MPGN in a child presenting with proteinuria, hematuria on school urinary screening tests. He had been treated with losartan and enalapril. This is the first case report of type II MPGN detected by school urinary screening tests in Korea. Thus we report a case of 10-years-old male with type II MPGN with a review of brief literature.

Da Vinci Robot-Assisted Pulmonary Lobectomy in Early Stage Lung Cancer: 3 cases report / 대한흉부외과학회지

Video-assisted pulmonary lobectomy was introduced in the early 1990's by several authors, and the frequency of video-assisted thoracic surgery (VATS) lobectomy for lung cancer has been slowly increasing because of its safety and oncologic acceptability in patients with early stage lung cancer. However, VATS is limited by 2D imaging, an unsteady camera platform, and limited maneuverability of its instruments. The da Vinci Surgical System was recently introduced to overcome these limitations. It has a 3D endoscopic system with high resolution and magnified binocular views and EndoWrist instruments. We report three cases of da Vinci robot system-assisted pulmonary lobectomy in patients with early stage lung cancer.

A Case of Verrucous Carcinoma of the Hard Palate and the Nasal Floor / 대한이비인후과학회지

Verrucous carcinoma is a distinct morphologic variant of well differentiated squamous cell carcinoma that is most often seen in the oral cavity & larynx but extremely rare in the nasal cavity. This neoplasm has been characterized as a slow growing lesion in elderly smokers with poor oral hygiene. It is histologically and locally invasive but metastasis is rare. We report a case of verrucous carcinoma found in the hard palate & the nasal floor and treated by surgical excision with a review of the literature.