PURPOSE: To evaluate biological characteristics of neutron beam generated by MC50 cyclotron located in the Korea Institute of Radiological and Medical Sciences (KIRAMS). MATERIALS AND METHODS: The neutron beams generated with 15 mm Beryllium target hit by 35 MeV proton beam was used and dosimetry data was measured before in-vitro study. We irradiated 0, 1, 2, 3, 4 and 5 Gy of neutron beam to EMT-6 cell line and surviving fraction (SF) was measured. The SF curve was also examined at the same dose when applying lead shielding to avoid gamma ray component. In the X-ray experiment, SF curve was obtained after irradiation of 0, 2, 5, 10, and 15 Gy. RESULTS: The neutron beams have 84% of neutron and 16% of gamma component at the depth of 2 cm with the field size of 26 x 26 cm2, beam current 20 micro A, and dose rate of 9.25 cGy/min. The SF curve from X-ray, when fitted to linear-quadratic (LQ) model, had 0.611 as alpha/beta ratio (alpha=0.0204, beta=0.0334, R2=0.999, respectively). The SF curve from neutron beam had shoulders at low dose area and fitted well to LQ model with the value of R2 exceeding 0.99 in all experiments. The mean value of alpha and beta were -0.315 (range, -0.254 ~ -0.360) and 0.247 (0.220~0.262), respectively. The addition of lead shielding resulted in no straightening of SF curve and shoulders in low dose area still existed. The RBE of neutron beam was in range of 2.07~2.19 with SF=0.1 and 2.21~2.35 with SF=0.01, respectively. CONCLUSION: The neutron beam from MC50 cyclotron has significant amount of gamma component and this may have contributed to form the shoulder of survival curve. The RBE of neutron beam generated by MC50 was about 2.2.
Beryllium ; Cell Line ; Cyclotrons* ; Gamma Rays ; Korea ; Neutrons* ; Population Characteristics* ; Protons ; Shoulder

Faun-tail presents as an abnormal lumbosacral hypertrischosis and may be associated with spinal dysrasphism. In addition to the problems due to spinal anomalies, patient's physico-social life may also be affected. Here, we report a case of 13 years old female patient with Faun-tail in association with sypinal dysraphism, in which cosmetic improvement was achieved with the help of Alexandrite laser. Alexandrite laser can be the method of choice for permanent hair removal method due to its safe, effective and easy to apply properties.
Beryllium ; Cosmetics ; Female ; Hair Removal ; Humans ; Lasers, Solid-State ; Nevus ; Spinal Dysraphism

PURPOSE: Ni-Cr alloy does not contain Beryllium, causing the metal compound to form oxides in the furnace but by using Titanium as a chemical catalyst the forming of the oxides can be controlled, and by controlling the impurities formed on the metal surface, the possibility of the Ni-Cr alloy bond strength being increased can be analysed. MATERIALS AND METHODS: Titanium was used as a chemical catalyst in the porcelain for the oxidation of beryllium-free metal (Ni-Cr) alloy. The T1 group, which does not use Titanium power as a chemical catalyst is a reference model for comparison. The T2 group and T3 group used 10 g and 20 g of Titanium power, respectively. They are fabricated to observe the shear bond strength and surface properties. There was no significance when One-way ANOVA analysis/Tukey Honestly Significant Difference Test was conducted for statistical analysis among groups (P > 0.05). RESULTS: Results of measuring the three-point flexural bond strength of the Ni-Cr alloy and thickness of the oxide film. Experiment T3 using 20 g Titanium chemical catalyst: 39.22 ± 3.41 MPa and 6.66 µm, having the highest bond strength and thinness of oxide film. Experiment T2 using 10 g Titanium chemical catalyst: 34.65 ± 1.39 MPa and 13.22 µm. Experiment T1 using no Titanium chemical catalyst: 32.37 ± 1.91 MPa and 22.22 µm. CONCLUSION: The T2 and T3 experiments using Titanium chemical catalyst showed higher bond strength for the Ni-Cr alloy and lower thickness of oxide film than experiment T1, and the titanium catalyst being able to increase bond strength was observed.
Alloys ; Beryllium ; Dental Porcelain ; Hot Temperature* ; Oxides ; Surface Properties ; Thinness ; Titanium*

Animals ; Beryllium ; toxicity ; Cells, Cultured ; DNA Damage ; drug effects ; Lung ; cytology ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the effect of gilding technique on the element release from Vera Bond Ni-Cr-Be alloy exposed to artificial saliva.

METHODSTo measure the quantity of beryllium ion which was released from common used Ni-Cr porcelain crown (controlling group), polished Ni-Cr porcelain crown (polished group), gilded Ni-Cr porcelain crown (gold-plating group) and gilded Ni-Cr porcelain crown prolonged 50% (gold-plating prolonged 50% group) in artificial saliva after 1 month, 3 months and 6 months by means of ICP-AES. So the effect of released beryllium ion with different treatments and the rule of different times with the same treatment were compared.

RESULTSThe quantity of released beryllium ion was statistic significant among different treatments. The quantity of released beryllium ion was gradually increased with the same treatment. At the end of this experiment, it was reached the highest. The speed of released beryllium ion was gradually decreased with the same treatment. At the end of this experiment it was reached the lowest.

CONCLUSIONThe gilding treatment can decrease the quantity of beryllium ion which released from Ni-Cr porcelain crown, and improve the biocompatibility.

Alloys ; Beryllium ; Chromium Alloys ; Crowns ; Dental Alloys ; Dental Porcelain ; Gold ; Humans ; Saliva, Artificial

Macaque monkeys are good sentinel to humans for environmental pollutions because their similarities in genetic and physiological characteristics. So, their reference values about exposures to heavy metals are required for proper data interpretation. Here, we report several heavy metals concentrations in the hair of rhesus monkeys which are widely used in biomedical research. The hair of 28 imported rhesus monkeys from an animal farm in southwest China were examined for the presence of eight heavy metals (Arsenic, Beryllium, Cadmium, Chromium, Iron, Lead, Mercury, and Selenium). The analyzed data in parts per million (ppm) for hair concentrations of heavy metals in rhesus monkeys were as follow: As (0.654+/-0.331), Be (0.005+/-0.003), Cd (0.034+/-0.022), Cr (11.329+/-4.259), Fe (87.106+/-30.114), Pb (0.656+/-0.613), Hg (0.916+/-0.619), and Se (3.200+/-0.735). The concentrations of Be, Cr, and As showed significant higher in females than in males (P<0.05). We present here the reference values of several heavy metals in healthy China-origin rhesus monkeys. These data may provide valuable information for veterinarians and investigators using rhesus monkeys in experimental studies.
Animals ; Beryllium ; Cadmium ; China ; Chromium ; Female ; Hair ; Haplorhini ; Humans ; Iron ; Macaca ; Macaca mulatta ; Male ; Metals, Heavy ; Nitriles ; Pyrethrins ; Reference Values ; Research Personnel ; Veterinarians

Occupational lung diseases are caused by several toxic substances including heavy metals; however, the exact pathologic mechanisms remain unknown. In the workplace, dental technicians are often exposed to heavy metals such as cobalt, nickel, or beryllium and occasionally develop occupational lung diseases. We described a case of occupational lung disease in a patient who was employed as a dental technician for over a decade. A 31-year-old, non-smoking woman presented with productive cough and shortness of breath of several weeks duration. Chest computed tomography revealed a large number of scattered, bilateral small pulmonary nodules throughout the lung field, and multiple mediastinal lymph nodes enlargement. Percutaneous needle biopsy showed multifocal small granulomas with foreign body type giant cells suggestive of heavy metals inhalation. The patient's condition improved on simple avoidance strategy for several months. This case highlighted the importance of proper workplace safety.
Adult ; Beryllium ; Biopsy, Needle ; Cobalt ; Cough ; Dental Technicians* ; Dyspnea ; Female ; Foreign Bodies* ; Giant Cells, Foreign-Body ; Granuloma ; Humans ; Inhalation ; Lung ; Lung Diseases ; Lymph Nodes ; Metals, Heavy ; Nickel ; Thorax

OBJECTIVES: We conducted an epidemiological survey to inquire into an outbreak of acute pneumonitis after two reported cases of interstitial lung disease. METHODS: The study subjects were 45 workers from a compound metal alloy factory. We reviewed the factory's industrial hygiene data along with the results of a special health examination, including pulmonary function tests, simple chest X-rays, and high resolution computed tomography. RESULTS: The air concentrations of beryllium ranged from 0.42 microgram/m3 to 112.3 microgram/m3, and the mean concentration of urinary beryllium were 1.53+/-0.79 microgram/g of creatinine in the molding workers, 1.41+/- 0.50 microgram/g of creatinine in the casting workers, and 1.16+/-0.53 microgram/g of creatinine in the sorting workers. The rates for cough (p=0.054), dyspnea (p=0.030), and the use of medical services (p=0.018) were higher in the molding workers than in the non-molding workers. The incidence rate of acute interstitial lung disease was higher for the molding process (32.0%) than for the non-molding process (5.0%) (p=0.012). The time of employment for all patients was prior to December 1st, 2002. CONCLUSIONS: Since most of the patients were molding workers, and all of the patients had worked without a ventilation system, this outbreak of acute interstitial lung disease was regarded as acute beryllium disease. Although the direct cause of the epidemic was the beryllium fumes, the fundamental cause was improper control of the work environment. Therefore, the means for preventing avoidable epidemics of occupational diseases are discussed.
Alloys ; Berylliosis ; Beryllium ; Cough ; Creatinine ; Dyspnea ; Employment ; Fungi ; Humans ; Incidence ; Lung ; Lung Diseases, Interstitial ; Occupational Diseases ; Occupational Health ; Pneumonia ; Respiratory Function Tests ; Thorax ; Ventilation

OBJECTIVES: We conducted an epidemiological survey to inquire into an outbreak of acute pneumonitis after two reported cases of interstitial lung disease. METHODS: The study subjects were 45 workers from a compound metal alloy factory. We reviewed the factory's industrial hygiene data along with the results of a special health examination, including pulmonary function tests, simple chest X-rays, and high resolution computed tomography. RESULTS: The air concentrations of beryllium ranged from 0.42 microgram/m3 to 112.3 microgram/m3, and the mean concentration of urinary beryllium were 1.53+/-0.79 microgram/g of creatinine in the molding workers, 1.41+/- 0.50 microgram/g of creatinine in the casting workers, and 1.16+/-0.53 microgram/g of creatinine in the sorting workers. The rates for cough (p=0.054), dyspnea (p=0.030), and the use of medical services (p=0.018) were higher in the molding workers than in the non-molding workers. The incidence rate of acute interstitial lung disease was higher for the molding process (32.0%) than for the non-molding process (5.0%) (p=0.012). The time of employment for all patients was prior to December 1st, 2002. CONCLUSIONS: Since most of the patients were molding workers, and all of the patients had worked without a ventilation system, this outbreak of acute interstitial lung disease was regarded as acute beryllium disease. Although the direct cause of the epidemic was the beryllium fumes, the fundamental cause was improper control of the work environment. Therefore, the means for preventing avoidable epidemics of occupational diseases are discussed.
Alloys ; Berylliosis ; Beryllium ; Cough ; Creatinine ; Dyspnea ; Employment ; Fungi ; Humans ; Incidence ; Lung ; Lung Diseases, Interstitial ; Occupational Diseases ; Occupational Health ; Pneumonia ; Respiratory Function Tests ; Thorax ; Ventilation

OBJECTIVETo investigate injury to epidermal melanocyte by Q-switched Alexandrite laser.

METHODSMultiple biopsies were performed on 5 patients with nevus of Ota from before irradiation to 1 year after irradiation. Fourteen specimens were obtained for light microscopy, and 17 for transmission electron microscopy.

RESULTSMelanosomes in epidermal melanocytes were both smaller in size and fewer in number than those in dermal melanocytes. Immediately after irradiation, focal extracellular vacuoles of the basal layer could be observed under light microscopy. Most epidermal melanocytes underwent mild or moderate injury in the form of vacuolated melanosomes, swollen mitochondria, dilation of endoplasmic reticulum, and expansion of extracellular space, retaining intact cell membranes. Normal structures were restored 5 months to 1 year after irradiation, with no depigmentation or hyperpigmentation as seen by light microscopy.

CONCLUSIONInjury of melanosomes in epidermal melanocytes is reversible.

Adolescent ; Adult ; Beryllium ; therapeutic use ; Female ; Humans ; Laser Therapy ; Lasers ; adverse effects ; Melanocytes ; radiation effects ; Microscopy, Electron ; Nevus of Ota ; pathology ; radiotherapy ; ultrastructure ; Skin Neoplasms ; pathology ; radiotherapy ; ultrastructure