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PubMed1994

Clinical, histologic, and ultrastructural evaluation of tattoos treated with three laser systems.

We examined the response of tattoo pigments treated with three commercially available lasers: Q-switched ruby, Q-Switched neodynium:yttrium,aluminum,garnet (Nd:YAG), and the alexandrite. Tattoos applied to hairless guinea pigs and treated with the aforementioned lasers were evaluated clinically, histologically, and ultrastructurally. Clinical evaluation showed red brown, dark brown, and orange pigment responded best to the Nd:YAG laser (1064 nm). The alexandrite laser was most effective for removing blue and green pigment, the Q-switched ruby laser was most effective for removing purple and violet pigment, and the Nd:YAG laser (532 nm) removed red pigment the best. Black pigment was lightened equally with the Nd:YAG laser (1064 nm) and (532 nm) and the alexandrite laser (755 nm). No clinical scarring was observed; however, some colors turned black after treatment. Histologic and ultrastructural examination showed epidermal and dermal damage to be most evident after treatment with the Nd:YAG laser. Our study shows that certain tattoo pigments respond better to different laser systems.

Aluminum Oxide↗
PubMed2003

[Diffuse interstitial lung disorders caused by the environment and occupation].

Diffuse interstitial lung diseases caused by exogenous factors can be divided into those that arise as a result of a progressive accumulation of (mainly) mineral particles in the lung parenchyma, and those that essentially result from a particular susceptibility of the host for specific agents. The former category consists mainly of silicosis, coal worker's pneumoconiosis and asbestosis, as well as other mineral pneumoconioses. The latter category contains extrinsic allergic alveolitis, which is mainly caused by the inhalation of bio-aerosols, chronic beryllium disease and other sarcoid-like diseases, and hard-metal or cobalt lung. Individual susceptibility is based on a genetic tendency for becoming immunologically sensitized (demonstrated for beryllium) and/or possibly on a poor defense against oxidative stress (probably relevant for cobalt). Recent outbreaks of interstitial lung disease resulting from inhalatory exposure to some polymers ("Ardystil syndrome" and "flock worker's lung") show that one should remain vigilant for the occurrence of novel occupational causes of pulmonary disease.

Disease Susceptibility↗
PubMed1999

Increased glutathione and glutathione peroxidase in lungs of individuals with chronic beryllium disease.

Reactive oxygen species (ROS) are mediators of chronic tissue damage and fibrosis. Endogenous antioxidants may increase in response to oxidants and reduce tissue injury. We investigated the antioxidant response of the lungs to the chronic release of ROS, as occurs in the immune-specific granulomatous inflammation of chronic beryllium disease (CBD), and compared it with that in healthy controls and individuals exposed to cigarette smoke. The antioxidants superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glutathione (GSH) were quantitated in lung epithelial lining fluid (ELF) and serum from control subjects (n = 10), cigarette smokers (n = 8), and individuals with CBD (n = 9). GPx activity and extracellular GPx (eGPx) protein were increased in the ELF of subjects with CBD in comparison with that of control subjects and smokers (eGPx in ELF: controls, 1.3 +/- 0.2 microgram/ml, smokers, 1.9 +/- 0.3 microgram/ml, CBD, 3.8 +/- 0.8 microgram/ml; p = 0.002; GPx U/ml ELF, controls 1.4 +/- 0.3, smokers 1.8 +/- 0.4, CBD, 4.5 +/- 1, p = 0.02). Smokers' ELF had higher levels of GSH than that of controls, but CBD patients' ELF contained much more GSH than that of either controls or smokers (p < 0.001). Increases in GSH were correlated with eGPx, indicating similar inducing mechanisms for these antioxidants. Thus, coordinate augmentation of the glutathione antioxidant system occurs in granulomatous lung inflammation.

Adolescent↗
PubMed1978

Dental porcelain/Ni alloy interface reactions and their effective prevention.

In a Be-bearing Ni alloy porcelainized without preoxidation, Be diffuses to the interface, oxidizes, and oxygen is supplied by the atmosphere at the porcelain surface and by reduction of SiO2 at the porcelain-alloy interface. On the alloy side of the interface, pits develop locally and near them Ni and Cr oxidize. In the oxide, Ni and Si are reduced to form nickel silicides. Preoxidation of the alloy prevents Be oxidation and Si reduction for several hours of porcelainization.

Beryllium↗
PubMed1989

Laser microprobe mass spectrometry (LAMMS) analysis of beryllium, sarcoidosis and other granulomatous diseases.

Beryllium was detected in the granulomas of all thirty-three cases of CBD examined and was absent in thirty cases of sarcoidosis. It was also found in association with coal dust in one of twelve normal lungs. Beryllium could also be detected in Schaumann bodies and hyalinized scars. Beryllium, though sometimes present in Kveim negative biopsies of CBD patients, was not found in any originating Kveim antigen. Rare earths (La, Ce, Pr and Nd) were unexpectedly found in two of the thirty sarcoid patients but not in any other samples. We have identified the crystalline component of Schaumann bodies as calcite and shown that they, as well as calispherules of microlithiasis, contain calcium phosphate. Al and Ti may be found in normal lungs but when associated with hypersensitivity granulomatous disease, their oxides were also present.

Berylliosis↗
PubMedDate not supplied

[Hygienic aspects of the impact of solid waste disposal sites on the habitat].

The "Dmitrovsky" solid garbage (SG) ground is one of the largest enterprises of this kind in the Moscow Region. A total of 200,000-750,000 tons of solid garbage (91%) and industrial waste products (9%) annually come to the ground. A total of 5,500,000 tons of garbage and waste products have been accumulated since it was put into operation. From the accumulated SG deposits, iron, manganese, beryllium, titanium, barium, boron, petroleum products enter the surface and underground waters, methane, carbon oxide, ammonia, toluene, xylene, hydrogen sulfide, cresol, phenol come into the atmospheric air; the compounds of zinc, lead, cadmium, copper, nickel, magnesium, and cobalt do into the soil. The studies conducted in 1997-2002 make it possible to establish that the ground has a negative impact on the environment and to evaluate the efficiency of nature-conservation and hygienic measures, and to improve the technological process of SG utilization.

Environment↗
PubMed1991

Flame atomic absorption spectrometric method for the determination of beryllium in natural waters after separation with N-benzoyl-N-phenylhydroxylamine.

A procedure for the determination of beryllium in natural waters is proposed. A solvent extraction step was performed in order to overcome interferences and isolate beryllium before it was atomized by direct nebulization of the organic phase in a dinitrogen oxide-acetylene flame. N-Benzoyl-N-phenylhydroxylamine was used as the extractant whilst isobutyl methyl ketone was the organic solvent. The effects of pH, amine concentration in the organic phase, shaking time, stability of the complex and nature of the extracted species were studied. The detection limit and linear response range are 2 ng ml-1 and 0-1.0 microgram ml-1, respectively. The result obtained for a standard reference material compared well with the quoted value.

Beryllium↗
PubMed1993

Surface analysis of nickel-chromium dental alloys.

In this study, the surface compositions of four commercially available nickel-chromium alloys, Neptune, Rexalloy, Regalloy T, and Vera Bond, were compared and correlated to the alloys' corrosion behavior. The alloys were chosen to be representative of alloys with acceptable and unacceptable Cr levels, with and without Be additions. The results showed that the non-Be-containing alloys exhibited a homogeneous Cr-Mo oxide surface which resulted in more corrosion resistant alloys. The Be-containing alloys were shown to have non-uniform oxide surfaces. Areas on the surfaces of these alloys were low in Cr and O and enriched in Be. The oxide surfaces of these alloys were more easily disrupted and provided little resistance to accelerated corrosion processes. Thus, it was found that not only were the Cr and Mo content of the alloys important for corrosion resistance, but the composition of the surface oxide as well.

Aluminum↗
PubMed1997

[The shear bond strength of porcelain and base metal alloys for metal-ceramic crown (VII)].

The popularity of the base metal alloys has increased in the past decade because of their lower price, high tensile strength and high elastic modulus. Several factors are critical in ensuring successful bonding: the matching of the thermal coefficients of expansion and constraction of the porcelain and metal, the metallurgic composition of the alloy and the pretreatment procedures used in preparation of the metal substructure. Two ceramic base alloys (one alloy contains beryllium, another without) were studied. The surface textures were created by 50 microns, 100 microns aluminum oxide sandblasting, carbide bur, carborundum point and disk upon two base alloys, Rexillium III and Wiron 88. The purposes of this investigation were to determine how these variations in surface texture affect the bond strength of the two ceramo-metal alloy systems. The following results were obtained: 1. Statistics revealed that bond strength was not significantly increased with surface roughness (p > 0.05). 2. The shear bond strength for variable pretreatment methods were in the following sequence: 100 microns Al2O3 sandblasting, carbide bur, 50 microns Al2O3 sandblasting, carborundum point, disk. 3. The Rexillium III alloy had a significantly higher bond strength than Wiron 88 alloy (p < 0.05). 4. The Noritake porcelain showed a significantly higher bond strength than Biobond porcelain (p < 0.05). 5. The fracture site was cohesive and adhesive mode treated with 50 microns Al2O3, 100 microns Al2O3, carbide bur. But carborundum point and disk was adhesive mode.

Crowns↗
PubMed1989

[Composition and morphology of oxides on porcelain fused to Ni-Cr alloys. Be containing alloys].

Bonding strength between porcelain and Ni-Cr alloy for the porcelain fused-to metal crown in which Be is contained in the alloy is known to be higher than those in which Be is not contained. Since, bonding between porcelain and alloy is the reaction of oxides and porcelain, the bonding is thought to be influenced by the quality the oxides film which forms on the alloy surface. The purpose of this study was to determine the composition and morphology of the oxides formed on both Be containing and non-Be contained Ni-Cr alloys. The oxides analysis was done using an EPMA and Auger analysis. Also, the Porcelain/Ni-Cr alloy interface was observed by a scanning electron microscope (SEM). The following results are indicated from this investigation: 1. The oxides from the alloys not containing Be are corundum type Cr2O3 and spinel type NiCr2O4. These oxide layers are uniform, thick and porous and the adhesion to alloy is poor. 2. The oxides from alloy containing Be is BeO only. The BeO is uniform, thin and condensed. The adhesion to the alloy is good. 3. The oxide layer formed when the porcelain is fused to alloy containing Be is thin (1 micron average) and has good adhesion to alloy. 4. Be is selectively oxidized and controlled the form of Cr2O3 and NiO.

Beryllium↗
PubMed1991

Genotoxicity of beryllium, gallium and antimony in short-term assays.

The genotoxicity of beryllium, gallium and antimony compounds was studied with the rec, Salmonella mutagenicity and SCE assays. In the rec assay, all the salts of the metals, BeCl2, Be(NO3)2, GaCl3, Ga(NO3)3, SbCl3, SbCl5, and an oxide, Sb2O3, had DNA-damaging activity. None of the compounds was mutagenic to Salmonella. In the SCE assays using V79 cells, 2 antimony(III) compounds, SbCl3 and Sb2O3, and 2 beryllium compounds, BeCl2 and Be(NO3)2, induced SCEs significantly. Sb2O3, slightly soluble in water, was positive in both the rec assay and the SCE assay at very low doses.

Animals↗