Direct effect of streptozotocin on periodontal ligament cells through myeloid cell leukemia-1.

OBJECTIVE: We hypothesized that streptozotocin (STZ) has a direct impact on periodontal ligament cell (PDL) damage as a potential direct inducer of periodontitis. BACKGROUND: Since diabetes was accepted as one of the risk factors for the development of periodontal disease, various scientific studies have been undertaken in the STZ-induced periodontal disease models. STZ induces ß-cell damage and subsequent diabetes development in vivo. Until now, assessment of the impacts of STZ-induced experimental diabetes on periodontitis has generally been conducted on the fundamental assumption that STZ have no direct action on PDL and its function. However, several recent studies suggest that STZ also directly affect many different biological functions in various tissues or organs. MATERIAL AND METHODS: To assess the apoptotic effects of STZ on PDLs, they were treated with or without STZ at different concentrations. Qualitative estimation of apoptotic cell death was obtained by live/dead assay. The expression levels of apoptosis-related proteins were evaluated by western blot analysis. RESULTS: STZ inhibits growth and induces apoptosis in PDLs in a dose-dependent manner. Furthermore, STZ dramatically induced Mcl-1 downregulation in a proteasome-dependent manner and thereby induced apoptosis of PDLs through the Bak/Bax apoptotic signaling pathway. CONCLUSION: Our results support the hypothesis that suppression of the cellular Mcl-1 levels by STZ may be at least partly attributed to the development of periodontitis in STZ-induced diabetic animal models.

Preliminary physical and electromagnetic design for the injector of the heavy ion superconducting linac.

The Rare Isotope Science Project in Korea has developed a high current heavy ion accelerator using superconducting linacs. A normal conducting injector system was proposed to supply heavy ions to the superconducting driver linac. A beam physics and engineering design study was performed, and the beam dynamics of the injector was simulated. Optimized beam transmission and emittance were obtained from the beam dynamics simulation. Various normal conducting bunchers, such as multi-harmonic buncher, velocity equalizer, radiofrequency quadrupole, and re-bunchers, will be used and have been electromagnetically calculated.

Superconducting magnets for the RAON electron cyclotron resonance ion source.

The RAON linear accelerator of Rare Isotope Science Project has been developed since 2011, and the superconducting magnet for ECRIS was designed. The RAON ECR ion source was considered as a 3rd generation source. The fully superconducting magnet has been designed for operating using 28 GHz radio frequency. The RAON ECRIS operates in a minimum B field configuration which means that a magnetic sextupole field for radial confinement is superimposed with a magnetic mirror field for axial confinement. The highest field strength reaches 3.5 T on axis and 2 T at the plasma chamber wall for operating frequency up to 28 GHz. In this paper, the design results are presented of optimized superconducting magnet consisting of four solenoids and sextupole. The prototype magnet for ECRIS was fabricated and tested to verify the feasibility of the design. On the basis of test results, a fully superconducting magnet will be fabricated and tested.

Design of the plasma chamber and beam extraction system for SC ECRIS of RAON accelerator.

The RAON accelerator is the heavy ion accelerator being built in Korea. It contains a 3rd generation SC ECRIS which uses 28 GHz/18 GHz microwave power to extract 12 puA uranium ion beams. A plasma chamber for that ECRIS is made of aluminum machined from bulk Al. That chamber contains cooling channels to remove dumped power and another access port for microwave introduction and plasma diagnostics. Beam extraction electrodes were designed considering the engineering issues and preliminary beam extraction analysis was done. That plasma chamber will be assembled with a cryostat, and beam extraction experiment will be done.

Design and construction of a compact microwave proton source for a proton linac.

A 100 MeV, 20 mA proton linear accelerator is being developed by the Proton Engineering Frontier Project at the Korea Atomic Energy Research Institute. 20 MeV acceleration system using radio frequency quadrupole and drift tube linac was already developed and has been tested. To operate this acceleration system with a long time, more reliable proton source is needed. A compact microwave proton source was proposed and has been designed and constructed as a prototype ion source for the 100 MeV proton linear accelerator. The design of microwave power injection system is based on the microwave proton injector at LANL and CEA. The wave power from a 2.45 GHz, 2 kW magnetron source is introduced into a compact plasma chamber with 7 cm diameter and 5 cm length through a standard tapered, double-ridged waveguide (WRD250) and a quartz window. The microwave power supply is installed on high voltage platform. Axial magnetic fields up to 1 kG can be provided with a water-cooled solenoid coil. A single-hole three electrode extraction system is designed for an extraction current up to 30 mA at a 50 kV extraction voltage. The design and initial operations of the proton source are presented.

Clinical usefulness of magnetic resonance cisternography in patients having hemifacial spasm.

To evaluate the usefulness of MR cisternography fourteen patients that had hemifacial spasm and 20 control patients underwent MR cisternography. All the patients with hemifacial spasm had a confirmed vascular compression after surgery. MR cisternography was performed using a 1.5-tesla superconducting MR magnet in which a 3D (dimensional) heavily T2-weighted turbo spin-echo sequence was used. In 34 randomly selected individuals, we retrospectively determined whether MR cisternography images could be used to evaluate symptoms, and what the benefits of obtaining this image was. The results were correlated with the surgical findings. The sensitivity was 100% and the specificity was 94% in all patients having a hemifacial spasm. The offending vessels were the anterior inferior cerebellar artery (AICA) in six patients cases, the posterior inferior cerebellar artery (PICA) in six, both the vertebral artery and PICA in one, and the vertebral artery in one. All the images showed good resolution and contrast, and also showed the exact correlation between the facial nerve and intracranial vessels in the multiplaner image. The findings of neurovascular compression were well correlated with the surgical findings. We believe that high-resolution 3D MR cisternography is a very useful method for evaluating the neurovascular compression in patients that have hemifacial spasm.

CT manifestations of cervical tuberculous lymphadenitis.

Cervical tuberculous lymphadenitis is a commonly encountered disease, especially in Korea. Differentiation from other metastatic lymphadenopathies and benign conditions such as cystic neck masses is important. CT findings of tuberculous lymphadenopathy in the abdomen and thorax are frequently reported in the literature, though there are only a few articles concerning cervical tuberculous lymphadenopathy. The authors retrospectively analyzed CT findings of 42 cases with cervical tuberculous lymphadenitis regarding distribution, contour, enhancing pattern, changes in the adjacent fascial plane, and dermal and subcutaneous manifestations. We concluded that the following are suggestive of tuberculous lymphadenitis: the presence of conglomerated nodal masses with central lucency, thick irregular rim of contrast enhancement and inner nodularity, varying degree of homogenous enhancement in smaller nodes, dermal and subcutaneous manifestations of inflammation such as thickening of the overlying skin, engorgement of the lymphatics and thickening of the adjacent muscles, and a diffusely effaced fascial plane. There were only a few cases of central low densities with calcifications on CT scan. However, common CT patterns of tuberculous adenitis may also be seen in other diseases, such as lymphoma and metastatic lymphadenopathy, and a thorough clinical examination and detection of primary lesions may be more helpful in differentiating these lymphadenopathies.

Actinomycosis of the neck: diagnosis by fine-needle aspiration biopsy.

A patient with actinomyces infection of the posterior neck was diagnosed by fine-needle aspiration biopsy. The lesion presented as a recurrent, firm, and indurated mass that was clinically diagnosed as adenitis and cellulitis and was thought to be a lymphoma 6 months after the onset of his illness. Smears and cell block sections of the aspirate showed characteristic colonies ("sulfur granules") of actinomyces. Subsequent regional lymph node biopsy revealed reactive lymphoid hyperplasia.

Multicentric gastrointestinal and extraintestinal leiomyosarcomatosis: a case report.

This article presents a case of synchronous polypoid primary adenocarcinoma of the transverse colon without lymph node or distance metastasis. During the postmortem examination, polypoid smooth muscle tumors in the patient's gastrointestinal tract and extensive extraintestinal smooth muscle tumors in the patient's liver, lungs, and visceral organs, including the diaphragm, parathyroid gland, bone marrow of the vertebrae, and subcutaneous tissue of the left wrist, were reviewed to determine their origin. Histomorphologically, all of the tumors were classified as leiomyosarcomas.

Cutaneous T cell lymphoma (mycosis fungoides) in blacks.

Between 1954 and 1980, 11 patients with cutaneous T cell lymphoma (mycosis fungoides) were diagnosed at the Howard University Hospital. There were five males and six females, all of whom were black. In association with the cutaneous T cell lymphoma, six cases of poikiloderma atrophicans vasculare were demonstrated.

Acropatia ulcero mutilante familiar: estudo clinico e genetico / Familiar acropathy ulcero-mutilating. Clinical and genetic study

Os autores realizam o estudo clinico e genetico em 101 individuos de uma familia distribuidos em cinco geracoes dos quais 11 eram portadores da "acropatia ulcero mutilante familiar". Concluem pela etiologia hereditaria monogenica padrao de heranca autossomica dominante e penetrancia completa

Cytologic findings in a case of malignant fibrous histiocytoma.

Morphologic changes in malignant cells obtained by needle aspiration of a recurrent malignant fibrous histiocytoma of the left axilla in a 61 year old male are reported. Basically, two types of cells are described: pleomorphic malignant histiocytic cells with marked phagocytic activity and sarcomatous spindle cells. Intermediate forms with features of both types are identified.

Thyroglossal cyst in black patients.

During the 16-year period, July 1, 1959 to June 30, 1975, inclusively, there were only 20 patients with thyroglossal cyst found at the Howard University Hospital (0.03 percent of routine surgicals). There were 12 males and eight females, all of whom were black. Anatomic and histopathologic variations of thyroglossal cysts will be emphasized, and the pitfalls in diagnosis discussed. A brief review of the literature will be presented.