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1.
Journal of Dental Rehabilitation and Applied Science ; : 71-79, 2017.
Artigo em Coreano | WPRIM | ID: wpr-80091

RESUMO

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.


Assuntos
Ligas , Berílio , Porcelana Dentária , Temperatura Alta , Óxidos , Propriedades de Superfície , Magreza , Titânio
2.
Tuberculosis and Respiratory Diseases ; : 445-449, 2015.
Artigo em Inglês | WPRIM | ID: wpr-149063

RESUMO

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.


Assuntos
Adulto , Feminino , Humanos , Berílio , Biópsia por Agulha , Cobalto , Tosse , Técnicos em Prótese Dentária , Dispneia , Corpos Estranhos , Células Gigantes de Corpo Estranho , Granuloma , Inalação , Pulmão , Pneumopatias , Linfonodos , Metais Pesados , Níquel , Tórax
3.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 512-516, 2015.
Artigo em Chinês | WPRIM | ID: wpr-350558

RESUMO

<p><b>OBJECTIVE</b>To explore beryllium oxide induced oxidative lung injury and the protective effects of LBP.</p><p><b>METHODS</b>Intoxication of animals were induced by once intratracheal injection and LBP intervention by intragastric administration. The content of HIF-1, VEGF and HO-1 of lung tissues were measured by kits. The pathological changes of lung tissue were showed by pathological section. The changes of lung ultrastructure were observed by electron microscope.</p><p><b>RESULTS</b>Pathological changes of the lung tissue in beryllium oxide exposure group rats were in line with the characteristics of beryllium disease in human. Compared with the control group, HO-1 was increased in beryllium oxide exposure 40 d group and low doses of LBP group, compared with the control group, HO-1 was increased in beryllium oxide exposure 80d group and LBP treatment groups (P < 0.05 or P < 0.01). Compared with the control group, HIF-1 was increased in beryllium oxide exposure 40 d group, LBP treatment groups, beryllium oxide exposure 60 d and 80 d groups (P < 0.05 or P < 0.01). Compared with the control group, VEGF was increased of all phases, especially in beryllium oxide exposure 40d and 80 groups, LBP treatment groups and beryllium oxide exposure 60 d (P < 0.05 or P < 0.01). The content of HO-1 of beryllium oxide exposure group was higher than the LBP treatment for 40d group but below LBP treatment for 80 d group (P < 0.05). The content of HIF1 of beryllium oxide exposure group was higher than high dose of LBP treatment for 60d group and LBP treatment for 80 d group (P < 0.01). The content of VEGF of beryllium oxide exposure group was higher than LBP treatment for 40 d group and high dose of LBP treatment for 60 d (P < 0.05 or P < 0.01).</p><p><b>CONCLUSIONS</b>BeO can cause abnormal expression of related genes of lung tissue in rats, LBP has protective effects on BeO caused lung injury.</p>


Assuntos
Animais , Ratos , Lesão Pulmonar Aguda , Proteínas de Fase Aguda , Farmacologia , Berílio , Toxicidade , Proteínas de Transporte , Farmacologia , Heme Oxigenase (Desciclizante) , Metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia , Metabolismo , Pulmão , Patologia , Glicoproteínas de Membrana , Farmacologia , Estresse Oxidativo , Substâncias Protetoras , Farmacologia , Fator A de Crescimento do Endotélio Vascular , Metabolismo
4.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 894-899, 2015.
Artigo em Chinês | WPRIM | ID: wpr-312095

RESUMO

<p><b>OBJECTIVE</b>To investigate the distribution of rubidium (Rb), cesium (Cs), beryllium (Be), strontium (Sr), and barium (Ba) in blood and urine in general Chinese population.</p><p><b>METHODS</b>A total of 18 120 subjects aged 6~60 years were enrolled from 24 regions in 8 provinces in Eastern, Central, and Western China from 2009 to 2010 based on the method of cluster random sampling. Questionnaire survey was conducted to collect the data on living environment and health status. Blood and urine samples were collected from these subjects, and the levels of Rb, Cs, Be, Sr, and Ba in these samples were determined by inductively coupled plasma mass spectrometry. The distribution of these elements in blood and urine in male or female subjects living in different regions was analyzed statistically.</p><p><b>RESULTS</b>In the general Chinese population, the concentration of Be in the whole blood was below the detection limit (0.06 μg/L); the geometric mean (GM) of Ba in the whole blood was below the detection limit (0.45 μg/L), with the 95th percentile (P95)of 1.37 μg/L; the GMs (95% CI)of Rb, Cs, and Sr in the whole blood were 2 374(2 357~2 392) μg/L, 2.01 (1.98~2.05) μg/L, and 23.5 (23.3~23.7) μg/L, respectively; in males and females, the GMs (95%CI)of blood Rb, Cs, and Sr were 2 506 (2 478~2 533) μg/L and 2 248 (2 227~2 270) μg/L, 1.88 (1.83~1.94) μg/L and 2.16 (2.11~2.20) μg/L, and 23.4 (23.1~23.7) μg/L and 23.6 (23.3~23.9) μg/L, respectively(P<0.01, P>0.05, and P>0.05). In the general Chinese population, the GM of urine Be was below the detection limit (0.06 μg/L), while the GMs (95%CI)of urine Rb, Cs, Sr, and Ba were 854 (836~873) μg/L, 3.65 (3.56~3.74) μg/L, 39.5 (38.4~40.6) μg/L, and 1.10 (1.07~1.12) μg/L, respectively; in males and females, the GMs (95%CI)of urine Rb, Cs, Sr, and Ba were 876 (849~904) μg/L and 832 (807~858) μg/L, 3.83 (3.70~3.96) μg/L and 3.47 (3.35~3.60) μg/L, 42.5 (40.9~44.2) μg/L and 36.6 (35.1~38.0) μg/L, and 1.15 (1.12~1.19) μg/L and 1.04 (1.01~1.07) μg/L, respectively (all P< 0.01). Correlation analyses showed that there were weak correlations between blood Rb and urine Rb (r=0.197)and between blood Sr and urine Sr (r=0.180), but a good correlation between blood Cs and urine Cs (r=0.487).</p><p><b>CONCLUSION</b>The levels of Rb, Cs, Be, Sr, and Ba in the general Chinese population are similar to those reported in other countries, and there is a significant difference in the concentration of each element among the populations living in different regions, as well as significant differences in blood Rb, urine Rb, urine Cs, urine Sr, and urine Ba between males and females.</p>


Assuntos
Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Bário , Sangue , Urina , Berílio , Sangue , Urina , Césio , Sangue , Urina , China , Limite de Detecção , Rubídio , Sangue , Urina , Estrôncio , Sangue , Urina
5.
Toxicological Research ; : 115-120, 2013.
Artigo em Inglês | WPRIM | ID: wpr-59640

RESUMO

To investigate the effects of short-term exposure of beryllium on the human immune system, the proportion of T-lymphocytes such as CD3+, CD4+, CD8+, CD95, and NK cells, andthe proportion of B cells and TNFalpha level in peripheral blood and immunoglobulins in the serum of 43 exposed workers and 34 healthy control subjects were studied. External exposure to beryllium was measured by atomic absorption spectrometer as recommended by the NIOSH analytical method 7300. T lymphocyte subpopulation analysis was carried out with flow cytometer. The working duration of exposed workers was less than 3 months and the mean ambient beryllium level was 3.4 microg/m3, 112.3 microg/m3, and 2.3 microg/m3 in molding (furnace), deforming (grinding), and sorting processes, respectively (cited from Kim et al., 2008). However, ambient beryllium level after process change was non-detectable (< 0.1 microg/m3). The number of T lymphocytes and the amount of immunoglobulins in the beryllium-exposed workers and control subjects were not significantly different, except for the total number of lymphocytes and CD95 (APO1/FAS). The total number of lymphocytes was higher in the beryllium-exposed individuals than in the healthy control subjects. Multiple logistic regression analysis showed lymphocytes to be affected by beryllium exposure (odd ratio = 7.293; p < 0.001). These results show that short-term exposure to beryllium does not induce immune dysfunction but is probably associated with lymphocytes proliferation.


Assuntos
Humanos , Absorção , Linfócitos B , Berílio , Fungos , Sistema Imunitário , Imunoglobulinas , Células Matadoras Naturais , Modelos Logísticos , Subpopulações de Linfócitos , Linfócitos , Linfócitos T , Fator de Necrose Tumoral alfa
6.
Braz. dent. j ; 23(4): 387-393, 2012. tab
Artigo em Inglês | LILACS | ID: lil-658015

RESUMO

Chemical disinfectants are usually associated with mechanical methods to remove stains and reduce biofilm formation. This study evaluated the effect of disinfectants on release of metal ions and surface roughness of commercially pure titanium, metal alloys, and heat-polymerized acrylic resin, simulating 180 immersion trials. Disk-shaped specimens were fabricated with commercially pure titanium (Tritan), nickel-chromium-molybdenum-titanium (Vi-Star), nickel-chromium (Fit Cast-SB Plus), and nickel-chromium-beryllium (Fit Cast-V) alloys. Each cast disk was invested in the flasks, incorporating the metal disk to the heat-polymerized acrylic resin. The specimens (n=5) were immersed in these solutions: sodium hypochlorite 0.05%, Periogard, Cepacol, Corega Tabs, Medical Interporous, and Polident. Deionized water was used as a control. The quantitative analysis of metal ion release was performed using inductively coupled plasma mass spectrometry (ELAN DRC II). A surface analyzer (Surftest SJ-201P) was used to measure the surface roughness (µm). Data were recorded before and after the immersions and evaluated by two-way ANOVA and Tukey's test (α=0.05). The nickel release proved most significant with the Vi-Star and Fit Cast-V alloys after immersion in Medical Interporous. There was a significant difference in surface roughness of the resin (p=0.011) after immersion. Cepacol caused significantly higher resin roughness. The immersion products had no influence on metal roughness (p=0.388). It could be concluded that the tested alloys can be considered safe for removable denture fabrication, but disinfectant solutions as Cepacol and Medical Interporous tablet for daily denture immersion should be used with caution because it caused greater resin surface roughness and greater ion release, respectively.


Desinfetantes químicos são normalmente associados a métodos mecânicos para remover manchas e reduzir a formação do biofilme. Este estudo avaliou o efeito de desinfetantes na liberação de íons metálicos e na rugosidade superficial do titânio comercialmente puro, ligas metálicas e resina acrílica termopolimerizável, simulando 180 ensaios de imersões. Espécimes em formato de discos foram confeccionados com titânio comercialmente puro (Tritan), liga de níquel-cromo-molibdênio-titânio (Vi-Star), liga de níquel-cromo (Fit Cast-SB Plus) e liga de níquel-cromo-berílio (Fit Cast-V). Os espécimes (n=5) foram imersos nestas soluções: hipoclorito de sódio a 0,05%, Periogard, Cepacol, Corega Tabs, Medical Interporous e Polident. Como controle, foi utilizada a água deionizada. A análise quantitativa de liberação de íons metálicos foi realizada por meio de espectrometria de massa com plasma indutivamente acoplado (ELAN DRC II). O rugosímetro (Surftest SJ-201P) foi utilizado para medir a rugosidade superficial (µm). Os dados foram registrados antes e depois das imersões e avaliados por ANOVA com dois fatores e teste de Tukey (α=0,05). A liberação de níquel provou ser mais expressiva nas ligas Vi-Star e Fit Cast-V após a imersão em Medical Interporous. Houve diferença significante na rugosidade superficial da resina (p=0,011) após a imersão. O Cepacol causou maior rugosidade superficial de forma significativa. Os produtos de imersão não influenciaram nos resultados da rugosidade do metal (p=0,388). Pode-se concluir que as ligas metálicas testadas podem ser consideradas seguras para a fabricação de próteses removíveis, mas as soluções desinfetantes como o Cepacol e a pastilha Medical Interporous para a imersão diária da prótese devem ser utilizados com cautela, pois causaram maior rugosidade superficial da resina e maior liberação de íons, respectivamente.


Assuntos
Humanos , Bases de Dentadura , Ligas Dentárias/química , Higienizadores de Dentadura/química , Resinas Acrílicas/química , Ligas/química , Alumínio/análise , Berílio/análise , Boratos/química , Cetilpiridínio/química , Clorexidina/análogos & derivados , Clorexidina/química , Ligas de Cromo/química , Cromo/análise , Ácido Cítrico/química , Desinfetantes de Equipamento Odontológico/química , Materiais Dentários/química , Teste de Materiais , Metais/análise , Metais/química , Molibdênio/análise , Níquel/análise , Espectrofotometria Atômica , Propriedades de Superfície , Hipoclorito de Sódio/química , Sulfatos/química , Titânio/análise , Titânio/química
7.
Laboratory Animal Research ; : 151-154, 2012.
Artigo em Inglês | WPRIM | ID: wpr-164979

RESUMO

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.


Assuntos
Animais , Feminino , Humanos , Masculino , Berílio , Cádmio , China , Cromo , Cabelo , Haplorrinos , Ferro , Macaca , Macaca mulatta , Metais Pesados , Nitrilas , Piretrinas , Valores de Referência , Pesquisadores , Médicos Veterinários
8.
Annals of Dermatology ; : S296-S298, 2011.
Artigo em Inglês | WPRIM | ID: wpr-62752

RESUMO

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.


Assuntos
Feminino , Humanos , Berílio , Cosméticos , Remoção de Cabelo , Lasers de Estado Sólido , Nevo , Disrafismo Espinal
9.
Korean Journal of Occupational and Environmental Medicine ; : 1-8, 2008.
Artigo em Coreano | WPRIM | ID: wpr-142604

RESUMO

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.


Assuntos
Humanos , Ligas , Beriliose , Berílio , Tosse , Creatinina , Dispneia , Emprego , Fungos , Incidência , Pulmão , Doenças Pulmonares Intersticiais , Doenças Profissionais , Saúde Ocupacional , Pneumonia , Testes de Função Respiratória , Tórax , Ventilação
10.
Korean Journal of Occupational and Environmental Medicine ; : 1-8, 2008.
Artigo em Coreano | WPRIM | ID: wpr-142601

RESUMO

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.


Assuntos
Humanos , Ligas , Beriliose , Berílio , Tosse , Creatinina , Dispneia , Emprego , Fungos , Incidência , Pulmão , Doenças Pulmonares Intersticiais , Doenças Profissionais , Saúde Ocupacional , Pneumonia , Testes de Função Respiratória , Tórax , Ventilação
11.
Iranian Journal of Dermatology. 2007; 9 (4): 319-323
em Inglês | IMEMR | ID: emr-83143

RESUMO

Laser is one of the most recent techniques which has widespread use in the treatment of many skin diseases. This technique has been successfully used to remove unwanted hairs in hirsutism. The aim of this study was to evaluate and compare the efficacy and safety of long-pulsed 755 nm alex and rite and long-pulsed 1064 nm Nd: YAG lasers individually and in combination for permanent hair removal. This single-blind r and omized clinical trial was conducted on 25 patients. They were treated by alex and rite or Nd: YAG or combination of them in 4 sessions with 8 weeks intervals. The treatment was applied on their medial and lateral sides of both legs. All the parameters of the systems were set on the company defaults. Subjects were evaluated 1 and 8 months after completion of the treatment. Hair count was measured by Visiomed device and digital camera photographs every session. To calculate mean hair reduction, the difference between hair count before and after treatment was divided by hair count before treatment. Pain severity, measured by Visual Analogue Scale [VAS], and side effects [bullae, scar and pigmentation changes] were recorded every session. The data were analyzed with ANOVA, post hoc Tukey and chi square tests. Fifteen patients completed the study and 10 patients were excluded due to appearance of bullae in 2 patients and refuse to continue in 8 patients. The mean hair reduction measured by Visiomed 8 months after last treatment was: 61.96 21.09, 60.03 23.40 and 68.05 21.23 percent for alex and rite, Nd: YAG and combination therapy, respectively. When digital camera photos were used for measurement of hair reduction these values were 85.99 11.62, 73.60 16.57 and 79.61 18.08 percent, respectively. The differences between the systems were not significant [ANOVA, P>0.05]. In paired comparison of the systems, no significant differences were observed either [Tukey test]. The incidence of adverse effects [hyperpigmentation] and pain severity were significantly greater in area received combination therapy [P<0.001]. Both alex and rite and Nd: YAG laser systems were effective in hair removal. In contrast, combination therapy did not have more efficacy and also caused more side effects


Assuntos
Humanos , Lasers , Hirsutismo/terapia , Berílio , Método Simples-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Bulletin of Alexandria Faculty of Medicine. 2007; 43 (3): 567-574
em Inglês | IMEMR | ID: emr-112193

RESUMO

The present case control study of sarcoidosis was designed to reveal some' epidemiological features, clinico-radiological presentations and possible factors affecting both the severity of the disease and the outcome of corticosteroid therapy. The study included 104 patients with sarcoidosis and 104 control subjects. The diagnosis of sarcoidosis was established when clinico-radiological findings were supported by histopathological evidence of non caseating epitheliod cell granulomas. Data were collected from patients and controls during an interview using a pre-designed questionnaire. The mean age of disease occurrence was 34.2 years with a slight higher Incidence in women and it was not common among smokers. Dyspnea and cough were the main presenting complaints, while skin lesions were the most common extra-pulmonary presentation. Stage I was the predominant radiological finding, complete remission was the outcome of corticosteroid therapy in 70.19% of patients. Occupational exposure to aluminum, zirconium or beryllium, low socioeconomic state, family history of sarcoidosis, past history of tuberculosis and the delay in the diagnosis may affect both the severity of the disease and the outcome of corticosteroid therapy. We identified some epidemiological features of sarcoidosis in Alexandria and their relations to the clinico-radiological presentations of the disease and the response to corticosteroid therapy


Assuntos
Humanos , Masculino , Feminino , Sarcoidose/diagnóstico , Sinais e Sintomas , Diagnóstico por Imagem , Inquéritos e Questionários , Exposição Ocupacional , Berílio , Zircônio , Corticosteroides , Estudos de Casos e Controles
13.
Iranian Journal of Radiation Research. 2007; 5 (1): 41-44
em Inglês | IMEMR | ID: emr-135256

RESUMO

Miniature neutron sources with high neutron flux have abundant applications in medicine, industry and researches. The most important general characteristic of miniature neutron sources is their diameter which is 3mm in average. In this research, we have surveyed and designed an Am-Be miniature neutron source fabrication. This investigation resulted in creation of an Am-Be neutron source, using beryllium metal powder with 98% carat and 100-200 Imicrom mesh and Americium source with activity of about 200 ImicroCi. Neutron source designing was performed under safety and protective factors. The system was designed in two different forms based on the fluent yield of neutron or cut off neutron yield. The mean neutron flux of miniature neutron source was measured as 1.14 [n/sec.cm2], and it was calculated as 2.56 [n/sec.cm2] by MCNP [4C] code. Due to purity and mesh of beryllium, which were not calculated by MCNP code, the calculated flux via Monte Carlo method was approximately 2 times larger than neutron flux from fabricated miniature neutron sources. In order to fabricate the miniature neutron sources Am- Be with high efficiency, the americium sources with high activity and the target material [Be] in different forms are required


Assuntos
Método de Monte Carlo , Berílio
14.
West China Journal of Stomatology ; (6): 8-11, 2007.
Artigo em Chinês | WPRIM | ID: wpr-249769

RESUMO

<p><b>OBJECTIVE</b>To evaluate the effect of gilding technique on the element release from Vera Bond Ni-Cr-Be alloy exposed to artificial saliva.</p><p><b>METHODS</b>To 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.</p><p><b>RESULTS</b>The 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.</p><p><b>CONCLUSION</b>The gilding treatment can decrease the quantity of beryllium ion which released from Ni-Cr porcelain crown, and improve the biocompatibility.</p>


Assuntos
Humanos , Ligas , Berílio , Ligas de Cromo , Coroas , Ligas Dentárias , Porcelana Dentária , Ouro , Saliva Artificial
15.
The Journal of the Korean Society for Therapeutic Radiology and Oncology ; : 280-284, 2006.
Artigo em Coreano | WPRIM | ID: wpr-40225

RESUMO

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.


Assuntos
Berílio , Linhagem Celular , Ciclotrons , Raios gama , Coreia (Geográfico) , Nêutrons , Características da População , Prótons , Ombro
16.
Indian J Exp Biol ; 2004 Aug; 42(8): 798-802
Artigo em Inglês | IMSEAR | ID: sea-58997

RESUMO

Efforts have been made to minimize the toxic effect caused by beryllium. Adult cyclic rats of Sprague Dawley strain were administered a bolus dose of 50mg/kg beryllium nitrate intramuscularly. The chelation therapy with glutathione (GSH), dimercapto propane sulfonic acid (DMPS)+ selenium (Se) and D-Penicillamine (DPA) + Se was given for 3 days followed by a rest of 1,3 and 7 days respectively. The results revealed a significant fall in the blood sugar level, serum alkaline phosphatase activity, serum proteins. A significant rise in the transaminases i.e. aspartate aminotranferase and alanine aminotranferase pattern is indicative of leakage of enzymes from liver resulting in alterations in the cell permeability. A rise in the hepatic lipid peroxidation activity is a direct indication of oxidative damage resulting in free radical generation. Results of the distribution studies by atomic absorption spectrophotometry reveal an increased concentration of beryllium in liver and kidney followed by lung and uterus. The relative ability of 3 chelating agents to act as antagonists for acute beryllium poisoning have been examined in liver, kidney, lungs and uterus. The appreciable change in the beryllium concentration in various organs is duration-dependent during the entire period being highly significant after 7 days rest. From the biochemical assays, and distribution studies it can be assumed that DPA+Se was the most effective therapeutic agent followed by DMPS+Se and GSH. Thus it can be concluded that DPA+Se is a better therapeutic agent as compared to DMPS+Se and GSH.


Assuntos
Animais , Antioxidantes/administração & dosagem , Berílio/toxicidade , Terapia por Quelação , Feminino , Glutationa/administração & dosagem , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Penicilamina/administração & dosagem , Ratos , Ratos Sprague-Dawley , Selênio/administração & dosagem , Fatores de Tempo , Unitiol/administração & dosagem
17.
Indian J Exp Biol ; 2004 Jun; 42(6): 570-4
Artigo em Inglês | IMSEAR | ID: sea-63170

RESUMO

The therapeutic efficacy of chelating agents CaNa3DTPA (calcium trisodium diethylene triamine penta acetic acid) and Tiron (sodium-4,5-dihydroxy-1,3-benzene disulphonate) with and without antioxidant, alpha-Tocopherol was evaluated in the treatment of beryllium-induced toxicity in female albino rats. The animals were exposed to beryllium (as beryllium nitrate) at a dose of 1 mg/kg (ip) once a day for 28 consecutive days followed by chelation therapy by CaNa3DTPA (0.1 mM/kg, ip) and Tiron (471 mg/kg, ip) with and without alpha-Tocopherol (25 mg/kg, orally) for 5 consecutive days after toxicant administration. Tissue biochemistry revealed severe alterations in liver and kidney. A significant fall in total protein and glycogen contents, alkaline phosphatase, adenosine tri-phosphatase and succinic dehydrogenase level was noticed. On the contrary, an elevation in acid phosphatase was recorded. The significant rise in hepatic lipid peroxidation and decreased level of hepatic reduced glutathione showed toxicity due to beryllium. CaNa3DTPA with alpha-Tocopherol showed moderate therapeutic efficacy while Tiron in combination with alpha-Tocopherol exerted statistically more beneficial effects to reverse biochemical alterations in different variables altered due to beryllium intoxication.


Assuntos
Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico/farmacologia , Adenosina Trifosfatases/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Antioxidantes/farmacologia , Berílio/farmacologia , Quelantes/farmacologia , Quimioterapia Combinada , Feminino , Glutationa/metabolismo , Glicogênio/metabolismo , Rim/efeitos dos fármacos , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Magnésio/metabolismo , Nitratos/farmacologia , Ácido Pentético/farmacologia , Ratos , Ratos Sprague-Dawley , Succinato Desidrogenase/metabolismo , Fatores de Tempo , alfa-Tocoferol/metabolismo
18.
Egyptian Journal of Chemistry. 2003; 46 (1): 1-10
em Inglês | IMEMR | ID: emr-61927

RESUMO

The synthesis and characterization of a series of the reagent, 2-benzensulfonylthinyl [furyl] glyoxal-2-arylhydrazone used, are reported and some of their complexes with B [+3] and Be [+2] have been proposed. Spectral studies [elemental analysis, IR, [1] HNMR, UV-visible spectrometry], have been used to elucidate the stoichiometry of the above metal complexes. The application of using such ligand for determination of trace amounts of boron in soil is discussed


Assuntos
Boro/química , Berílio/química , Solo/análise , Espectrofotometria Ultravioleta
19.
Chinese Medical Journal ; (24): 597-601, 2003.
Artigo em Inglês | WPRIM | ID: wpr-324383

RESUMO

<p><b>OBJECTIVE</b>To investigate injury to epidermal melanocyte by Q-switched Alexandrite laser.</p><p><b>METHODS</b>Multiple 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.</p><p><b>RESULTS</b>Melanosomes 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.</p><p><b>CONCLUSION</b>Injury of melanosomes in epidermal melanocytes is reversible.</p>


Assuntos
Adolescente , Adulto , Feminino , Humanos , Berílio , Usos Terapêuticos , Terapia a Laser , Lasers , Melanócitos , Efeitos da Radiação , Microscopia Eletrônica , Nevo de Ota , Patologia , Radioterapia , Neoplasias Cutâneas , Patologia , Radioterapia
20.
Indian J Exp Biol ; 2002 May; 40(5): 575-82
Artigo em Inglês | IMSEAR | ID: sea-61765

RESUMO

The present study was conducted to evaluate the therapeutic effectiveness of chelating agents [glutathione, 2,3 dimercapto propane sulfonic acid (DMPS) and D-penicillamine (DPA)] in combination with antioxidant (sodium selenite) in beryllium induced toxicity in female rats. A bolus dose of 50mg/kg-beryllium nitrate was administered singly followed by chelation therapy with GSH, DMPS + Se and DPA + Se at various durations of 1,3 and 7 days respectively. Results revealed a significant fall in the glycogen content, whereas, a marginal fall in the protein was also observed. The enzymatic activity of alkaline phosphatase and adenosine triphosphatase was depleted; on the contrary, there was a significant rise in the acid phosphatase and glucose-6-phosphatase pattern. A rise in the hepatic lipid peroxidation activity is a direct indication of oxidative damage resulting in free radical generation. The distribution of the metal by atomic absorption spectrophotometry revealed an increased concentration of beryllium in liver and kidney, followed by lung and uterus. The relative ability of three chelating agents to act as antagonists, for acute beryllium poisoning, have been examined in liver, kidney, lungs and uterus. The appreciable change in the beryllium concentration in various organs is duration dependent during the entire period being highly significant at 7 days regimen. Biochemical and distribution studies reveal that DPA + Se was the most effective therapeutic agent followed by DMPS + Se and GSH.


Assuntos
Animais , Antioxidantes/farmacologia , Berílio/toxicidade , Quelantes/farmacologia , Feminino , Ratos
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