Adaptación marginal e interna de cofias fabricadas por métodos convencionales, CAD/CAM de fresado y sinterizado por láser / Marginal and internal adaptation of copings manufactured by conventional methods, CAD/CAM milling and laser sintering

Introducción: la adaptación marginal e interna de nuestras restauraciones fabricadas por fundición sistemas de fresado y sinterización láser es uno de los factores clínicos más importantes para el éxito de las prótesis fijas, previniendo el riesgo de microfiltración y enfermedad periodontal. Objetivo: evaluar la adaptación marginal e interna de cofias metálicas en aleación Cr-Co confeccionadas por técnicas convencionales, CAD/ CAM de fresado y sinterizado por láser. Material y métodos: estudio de tipo experimental, comparativo e in vitro. Se imprimió un modelo maestro en Cr-Co, proveniente del escaneo de un premolar preparado para corona completa, sobre el cual se diseñaron 30 cofias divididas en tres grupos: el primero que corresponde al grupo cofias fundidas fresadas en disco de cera A (A = 10), el segundo grupo cofias fresadas en disco de metal presinterizado B (B = 10) y el tercer grupo cofias impresas por sinterización láser C (C = 10). Se empleó la réplica de silicona, colocando silicona al interior de cada cofia, sobre el modelo maestro, simulando al cemento, mediante una máquina de ensayo universal se realizó una compresión de 50 N. Luego de retirar cada cofia se rellenaron con silicona pesada de adición, obteniendo una réplica de silicona. Se efectuaron dos cortes transversales en sentido vestíbulolingual y mesiodistal. Se observó el espesor de silicona VPS (vinil poliéter silicona) mediante un estereomicroscopio (Nikon SMZ745T), obteniendo valores en micrómetros. Para el análisis estadístico se utilizó el software SPSS 25 con el fin de realizar la prueba de normalidad y ANOVA de dos vías bajo un nivel de confianza del 95%. Resultados: el menor gap lo obtuvo el grupo de fresadas, seguido de las impresas y por último las fundidas por métodos convencionales. ANOVA de dos vías reveló diferencias estadísticamente significativas entre los tres grupos (p < 0.0001). Conclusiones: se encontró que el gap varía con cada método de fabricación, la técnica convencional de fundido mostró un mayor gap, ninguna excediendo el rango clínicamente aceptable (AU)

Introduction: the marginal and internal adaptation of our restorations manufactured by casting, milling systems and laser sintering is one of the most important clinical factors for the success of fixed prostheses, preventing the risk of microleakage and periodontal disease. Objective: evaluate the marginal and internal adaptation of metal copings in Cr-Co alloy made by conventional techniques, CAD/CAM milling and laser sintering. Material and methods: an experimental, comparative and in vitro study, a Cr-Co master model was printed from the scan of a premolar prepared for a full crown. An experimental, comparative and in vitro study, a Cr-Co master model was printed from the scan of a premolar prepared for a full crown, on which 30 caps divided into three groups were designed; the first group corresponds to the cast copings milled on a wax disc A (A = 10), the second group milled copings on a presintered metal disc B (B = 10) and the third group printed by laser sintering copings C (C = 10). The silicone replica was used, placing silicone inside each coping, on the master model, simulating cement, using a universal testing machine, a 50 N compression was performed. After removing each coping, they were filled with heavy addition silicone, obtaining a silicone replica. Two cross-sections were made in the buccolingual and mesiodistal direction., observing the thickness of the VPS (vinyl polyeter silicone) silicone using a stereomicroscope (Nikon SMZ745T), obtaining values in micrometers. For the statistical analysis, the SPSS 25 software was used in order to perform the normality and two-way ANOVA tests under a 95% confidence level. Results: the smallest gap was obtained by the milled group, followed by the printed ones and finally those cast by conventional methods. Two-way ANOVA revealed statistically significant differences between the three groups (p < 0.0001). Conclusions: the gap was found to vary with each fabrication method, the conventional casting technique showed a larger gap, none exceeding the clinically acceptable range (AU)

Post-implantation Deformation of Titanium Rod and Cobalt Chrome Rod in Adolescent Idiopathic Scoliosis

@#Introduction: Post-implantation rod deformation is anticipated in scoliosis surgery but the difference in rod deformation between titanium and cobalt chrome rod has not been elucidated. This study aims to compare the difference in rod deformation between two groups. Materials and Methods: Twenty-one adolescent idiopathic scoliosis (AIS) patients were recruited from a single center. The over-contoured concave rods were traced prior to insertion. Post-operative sagittal rod shape was determined from lateral radiographs. Rod deformation was determined using maximal rod deflection and angle of the tangents to rod end points. The differences between pre- and post-operative rod contour were analysed statistically. Rod deformation and thoracic kyphosis between two types of implants were analysed. Results:Both rods exhibited significant change of rod angle and deflection post-operatively. Curvature of the titanium rod and cobalt chrome rod decreased from 60.5° to 37°, and 51° to 28° respectively. Deflection of titanium rod and cobalt chrome rod reduced from 28mm to 23.5mm and 30mm to 17mm respectively. There was no significant difference between titanium and cobalt chrome groups with regard to rod angle (p=0.173) and deflection (p=0.654). Thoracic kyphosis was increased from 20° to 26° in titanium group but a reduction from 25° to 23° was noticed in cobalt chrome group, but these findings were not statistically significant. Conclusion: There was no statistical difference in rod deformation between the two groups. Thus, the use of titanium rod in correction of sagittal profile is not inferior in outcome compared with cobalt chrome but with lower cost.

Transcriptional regulation effect of constituents in Polygonum multiflorum Thunb.based on human progesterone X receptor(hPXR)mediated CYP3A4 rapid screening system / 中国药理学与毒理学杂志

OBJECTIVE This study investigated transcriptional regulation of the main chemical con-stituents of Polygonum multiflorum Thunb. including Stilbene Glucoside (THSG) and anthraquinone constituents (Emodin, Rhein, Aloeemodin, Chrysophanol and Physcion) and six potential liver injury constituents(gallic acid,quercetin,luteolin,kaempferol,resveratrol)on mediated by PXR CYP3A4.Early establishment of pregnane X receptor mediated CYP3A4 drug induced rapid screening technique was used to determine the effects of these constituents. METHODS First,effect of constituents on the cell activity was detected by MTS cell viability assay. IC50was calculated. Second, the expression vector and reporter vector were co-transfected into Hep G2 cells,10 μmol·L-1Rifampicin as a positive control, 10 μmol·L-1Ketoconazole as a negative control. After treated with different concentrations of (the an-thraquinone constituents concentrations were 2.5,5 and 10 μmol·L-1;the concentrations of Gallic Acid, Quercetin,Luteolin,Kaempferol,Apigenin,Resveratrol concentrations were 5,10 and 20 μmol·L-1)for 24 h,the cells were tested for dual luciferase activity.RESULTS The results show that the inhibitory ef-fect of THSG,Chrysophanol,Emodin,Rhein and Aloeemodin on CYP3A4 was inhibited by co-transfec-tion of pcDNA3.1 and pGL4.17-CYP3A4. The expression of pcDNA3.14-PXR and pGL4.17-CYP3A4 was induced by the four constituents. Besides, Emodin has a directly inducing effect. Four anthraqui-none constituentscan induce the effect of CYP3A4 by PXR, but Emodin can directly induce CYP3A4. THSG can inhibit CYP3A4,but in the presence of PXR plasmid can induce CYP3A4.For the six poten-tial liver injury constituents, results show that the plasmid pcDNA3.1 was cotransfected with pGL4.17-CYP3A4 regulation of Gallic Acid and Resveratrol on CYP3A4 inhibitory effects of Quercetin,Luteolin, Kaempferol have an induce effect; after pcDNA3.14-PXR and pGL4.17-CYP3A4 cotransfected, Quercetin, Luteolin, Kaempferol, Apigenin, Resveratrol have induced effect, three constituents'induc-tion effect had significant difference.CONCLUSION 12 kinds of Polygonum multiflorum Thunb.constit-uents have inhibitory or activating effects on CYP3A4, after the participation of PXR, 9 components have induced effects on CYP3A4, and the induction effect of 6 components has significant difference. The results suggested that we should pay attention to potential drug interactions when combined with Polygonum multiflorum Thunb.,and improve safety and efficacy.

Avaliação da remoção de cromo (III) por materiais compósitos porosos adsorventes de PE-g-MA, fibra de coco e quitosana, usando planejamento experimental / Evaluation of removal of chromium (III) by composite porous adsorbents materials of PE-g-MA, coconut fiber and chitosan using experimental design

RESUMO Os processos de adsorção podem ser empregados no tratamento de efluentes líquidos contendo metais pesados visando a reduzir os danos ambientais. Porém, o alto custo dos materiais adsorventes justifica a aplicação de adsorventes alternativos, como a fibra de coco (FC) e a quitosana (Q). Assim, este trabalho teve como objetivo desenvolver compósitos porosos adsorventes a partir da mistura de polietileno graftizado com anidrido maleico/FC/Q/NaCl, como agente porogênico (PE-g-MA/FC/Q/NaCl), e avaliar estatisticamente a capacidade de adsorção do cromo (III) em solução, com auxílio do software Statistica 5.0®. Os resultados mostraram que a eficiência do processo sofreu influência das dimensões da FC, do teor de Q e do pH da solução contendo Cr (III). A capacidade máxima de remoção de Cr (III) por unidade de massa do compósito foi de 42,28 mg.g-1.

ABSTRACT Adsorption processes can be employed in the treatment of wastewater containing heavy metals to reduce environmental damage. However, the high cost of adsorbent materials justifies the application of alternative adsorbents, such as coconut fiber (CF) and chitosan (C). Thus, this study aimed to develop porous composite adsorbents from the mixture of grafted maleic anhydride polyethylene/CF/C/NaCl, as porogen agent (PE-g-MA/CF/C/NaCl), and evaluate statistically adsorption capacity of chromium (III) solution, with the aid of software Statistica 5.0®. The results showed that the process efficiency was influenced by the size of the CF, the content of C and the pH of the solution containing Cr (III). The maximum removal capacity of Cr (III) per unit mass of the composite was 42.28 mg.g-1.

Determination of aluminum content in fried dough sticks by microwave digestion-chrome azurol S spectrophotometric method / 中华地方病学杂志

Objective To study a method for determination of aluminum in food,and to ensure food safety and public health.Methods Microwave digestion-chrome azurol S spectrophotometric method was used to detect the aluminum content in fried dough sticks.Detection limit,linear range,precision,accuracy and maximum absorption wavelength were calculated.Results The method detection limit was 0.08 μg,precision was 0.60％-5.90％,and recovery rate was 96.0％-102.3％,maximum absorption wavelengnth was 620 mm.Aluminum content in 10 samples of fried dough sticks were all exceeded the standard,which were 709.5,980.8,1 010.3,1 151.5,1 214.0,1 243.7,1 318.1,1 374.0,1 435.0 and 1 479.4 mg/kg.Conclusion The method is simple,reliable,reproducible and easy to be used.

Diseño y evaluación de un biosistema de tratamiento a escala piloto de aguas de curtiembres a través de la Eichhornia crassipes / Design and evaluation of a biosystem water treatment pilot-scale tannery through Eichhornia crassipes

Desde el punto de vista ambiental, el sector de curtiembres siempre ha sido catalogado como altamente contaminante, donde su proceso productivo del cuero a partir de un tratamiento físico-químico de pieles de animales genera contaminantes químicos como el cromo y desechos orgánicos que causan impactos ambientales negativos sobre los ecosistemas. Los ecosistemas naturales, tales como los humedales, son los sistemas más productivos en el mundo como resultado de la abundancia de luz, agua, nutrientes. Debido a esta abundancia y favorabilidad es común encontrar la presencia de plantas que han desarrollado adaptaciones morfológicas y bioquímicas permitiéndoles aprovechar al máximo las ventajas de estas condiciones de su entorno, las cuales han sido comúnmente denominadas malezas acuáticas. Entre estas malezas flotantes (macrofitas) se encuentra el Jacinto de Agua (Eichornia crassipes), el cual tiene una amplia presencia en los cuerpos húmedos de Cundinamarca (Colombia), presentan un alta capacidad invasiva desarrollando un esparcimiento elevado en estos sistemas acuáticos. Pero esta planta tiene la capacidad de transformar la materia orgánica y sobre todo acumular diferentes metales pesados en su morfología. En la presente investigación, se diseñó y construyó un biosistema de tratamiento para la remoción y retención de cromo de aguas contaminadas por los residuos del proceso de las curtiembres, siendo la Eichhornia crassipes, el agente retenedor de estos compuestos contaminantes, donde se evidencio una solución económica y tecnológicamente viable para el sector industrial.

From the environmental point of view, the sector of tanneries always has been catalogued like highly pollutant, where his productive process of the leather from a treatment leather physicist - chemist of animals generates chemical pollutants as the chrome and organic waste that cause environmental negative impacts on the ecosystems. The natural, such ecosystems as the wetlands, they are the most productive systems in the world as result of the abundance of light, water, nutrients. Due to this abundance and favorabilidad is common to find the presence of plants that have developed morphologic and biochemical adjustments allowing them to take advantage to the maximum of the advantages of these conditions of his environment, which have been named commonly aquatic undergrowths. Between these floating undergrowths (macrofitas) one finds the Water hyacinth (Eichhornia crassipes), which has a wide presence in Cundinamarca's humid bodies (Colombia); they present a high invasive capacity developing a scattering raised in these aquatic systems. But this plant has the aptitude to transform the organic matter and especially accumulate different metals weighed in his morphology. In the present investigation, a biosistema of treatment was designed and constructed for the removal and retention of chrome of waters contaminated by the residues of the process of the tanneries, being the Eichhornia crassipes, the agent retainer of these pollutant compounds, where I demonstrate an economic and technologically viable solution for the industrial sector.

Las curtiembres de el cerrito (valle del cauca): una mirada en torno a su realidad socioeconómica y ambiental

El curtido de pieles es un proceso reconocido por el vertimiento de desechos químicos y orgánicos, así como por la liberación de compuestos volátiles de olores desagradables y desechos sólidos, que contaminan el agua, el aire y el suelo, produciendo efectos negativos en el ambiente natural y en la salud de la población. Considerando que este comportamiento está influenciado por componentes interrelacionados, el propósito de esta investigación fue identificar los principales factores socioeconómicos y ambientales que caracterizan la actividad curtidora en el municipio de El Cerrito, Valle del Cauca. Mediante el empleo de métodos cuantitativos y cualitativos, que incluyeron entrevistas con actores sociales clave, revisión bibliográfica y trabajo de campo, se pudo establecer que de 13 curtiembres activas, una de ellas corresponde a mediana empresa y las 12 restantes a microempresas (McEs), con cerca de 272 empleados directos. Dichas empresas han diversificado su actividad, dedicándose al curtido de pieles y al alquiler de servicios a curtidores informales. Las McEs presentan una baja capacidad de inversión en maquinaria y en equipos, en modernización tecnológica y en la adopción de programas e infraestructura de mejoramiento ambiental. Se evidenció la falta de conciencia ambiental, de planes de capacitación, de acompañamiento técnico y de políticas gubernamentales que promuevan su desarrollo y la adopción efectiva de programas de control y de prevención de la contaminación. Las características de este sector industrial hacen necesaria la implementación de programas integrales y adaptables a las McEs, de tal manera que conduzcan a mejorar su competitividad y sostenibilidad.

Tanning is a process recognized for the dumping of chemical and organic wastes, as well as the release of volatile compounds of unpleasant odors and solid wastes that pollute water, air and soil, producing negative effects on the environment and the health of the population. Since this behavior is influenced by interrelated components, the purpose of this research was to identify the main socioeconomic and environmental factors that characterize the tanning activity in the municipality of El Cerrito, Valle del Cauca. By using quantitative and qualitative methods, which included interviews with key social actors, literature review and fieldwork, it was established that 13 active tanneries, one corresponding to amedium enterprise and the remaining 12 to microenterprises (ECMs) with about 272 direct employees. These companies have diversified their activities, dedicated to tanning and rental services to informal tanners. ECMs have a low capacity for investment in machinery and equipment, technological modernization and the adoption of environmental programs and infrastructure improvement. The lack of environmental awareness, training plans, technical support and government policies that promote the development and adoption of effective control programs and pollution prevention was evident. The characteristics of this industry require the implementation of comprehensive and adaptable programs for ECMs, so leading to improve their competitiveness and sustainability.

Effect of berberine combined with bone marrow mesenchymal stem cells on energy metabolism of HUVECs damaged by high glucose / 中国药理学通报

Aim To investigate the effects of berberine combined with bone marrow mesenchymal stem cells ( BM-MSCs) on the energy metabolism of human um-bilical vein endothelial cells ( HUVECs ) under the condition of high glucose. Methods ①The state of cell reproduction and cell proliferating activity were de-termined by MTT assay. ②The cell cycle was detected by flow cytometry ( FCM ) . ③DNA damage of cells was measured by comet tail assay. ④The contents of ATP, ADP and AMP were determined by high perform-ance liquid chromatography ( HPLC ) and the level of energy charge ( EC) was calculated. ⑤The expression of CCR and COX mRNA was detected by reverse tran-scription-polymerase chain reaction ( RT-PCR) . ⑥The expressions of COX and CCR were detected by Western blot. Results ①The proliferating activity of HUVECs declined apparently and the proliferation decreased af-ter high glucose intervention. Meanwhile, the quantity of cells during S +G2 dropped dramatically and there was certain degree of damage to DNA. The berberine and BM-MSCs respectively improved the proliferating activity and the proliferation in different degrees, in-creased the quantity of cells during S+G2 and promo-ted the repair of DNA ( P <0 . 01 ) , and so did the combination of the two, with a better effect than each of them alone. ②After high glucose intervention and the damage caused, the content of both ATP and ADP of HUVECs was reduced, and EC level also declined significantly, while the content of AMP increased. The berberine and BM-MSCs respectively up-regulated the content of ATP and ADP ( P<0. 01 ) , and so did the combination of the two, with a better effect than each of them alone. ③After high glucose intervention and the damage caused, the expression of COX, CCR mR-NA and protein decreased obviously. Yet, all of the three gained a dramatic increase when the berberine, BM-MSCs or the combination of the two were added ( P<0. 01 or P <0. 05 ) , among which the combination worked more effectively. Conclusions The berber-ine, BM-MSCs and the joint use of the two could im-prove the energy metabolism of HUVECs, which had been damaged by high glucose, probably because the berberine and BM-MSCs could up-regulate the expres-sion of COX, CCR mRNA and protein, which leads to the hydrolyzation of glucose oxide and thus the im-provement of blood environment and the enhancement of glucose's supply and intake of HUVECs. Then, here comes the final result: the improvement of the energy metabolism of damaged vascular endothelial cells by high glucose.

Contaminação por metais pesados em peixes e água da bacia do rio Cassiporé, Estado do Amapá, Brasil / Heavy metal contamination in fish and water from Cassiporé River basin, State of Amapá, Brazil

A participação dos metais pesados nas reações químicas do metabolismo dos peixes tornou esses elementos um dos principais focos nos estudos de contaminação. O objetivo deste estudo foi determinar as concentrações dos metais Cd, Cr, Cu, Pb, Zn e Hg no tecido muscular de peixes da bacia do rio Cassiporé (Estado do Amapá) e ambiente, visando avaliar os riscos de contaminação. As concentrações de Cd em Plagioscion squamosissimus (1,061 µg g-1) e Pb em Poptella compressa (4,280 µg g-1) apresentaram valores que ultrapassam os limites estabelecidos pela legislação brasileira. As concentrações de Cr em P. compressa (0,937 ± 0,5 µg g-1), Pimelodella cristata (0,463 ± 0,03 µg g-1) e Cyphocharax gouldingi (0,364 ± 0,12 µg g-1), bem como de Hg em P. squamosissimus (0,670 µg g-1), Pseudoplatystoma fasciatum (0,630 µg g-1), Hoplias malabaricus (0,570 µg g-1 e Serrasalmus rhombeus (0,548 µg g-1) foram acima do limite legal. A coluna d'água apresentou altas concentrações de metais pesados em todos os pontos analisados, mostrando uma contaminação dessa bacia. Portanto, essas elevadas concentrações de metais pesados no ambiente e tecido muscular dos peixes indicam um elevado grau de contaminação na bacia do rio Cassiporé e risco a saúde do homem.

Heavy metals participate in chemical reactions of fish metabolism, which makes these elements a major focus on contamination studies. The objective of this study was to determine the concentrations of heavy metals Cd, Cr, Cu, Pb, Zn and Hg in muscle tissue of fish of Cassiporé River Basin (State of Amapá) and environment, aiming at assessing the risk of contamination. The concentrations of Cd in Plagioscion squamosissimus (1.061 µg g-1) and Pb in Poptella compressa (4.280 µg g-1) had values that exceed the boundaries established by Brazilian law. The Cr concentration in P. compressa (0.937 ± 0.5 µg g-1), Pimelodella cristata (0.463 ± 0.03 µg g-1) and Cyphocharax gouldingi (0.364 ± 0.12 µg g-1) and Hg in P. squamosissimus (0.670 µg g-1), Pseudoplatystoma fasciatum (0.630 µg g-1), Hoplias malabaricus (0.570 µg g-1 e Serrasalmus rhombeus (0.548 µg g-1) were above the legal limit. The water column showed high concentrations of heavy metals in all analyzed points, showing a contamination of this river basin. Therefore, the high concentrations of heavy metals in the environment and muscle tissue of fish indicate a high degree of contamination in the Cassiporé river basin and risk to human health.

Aspiración de cuerpo extraño durante la consulta dental en pediatría: Reporte de un caso / Foreign body aspiration in dental office: Founded suspicion for late diagnosis. Case presentation and literature review

Dentro de la práctica clínica en pediatría existen situaciones en las que el diagnóstico oportuno de una enfermedad involucra la meditación de situaciones insospechadas; en niños muy pequeños el interrogatorio indirecto bien realizado y detallado se convierte en herramienta fundamental para su tratamiento. En un evento de aspiración de cuerpo extraño existen indicadores específicos para tener sospecha de que estamos ante un caso; sin embargo, no todos los pacientes presentan signos y síntomas clásicos, por lo que la experiencia del clínico es vital. Se presenta el caso de un niño de veintiún meses de edad que broncoaspiró una corona de acero cromo en un consultorio dental; ésta no fue identificada sino hasta 60 días después del accidente. Es importante que los clínicos encargados de la salud bucal de los niños estén capacitados para auxiliar a sus pacientes ante un evento de aspiración de cuerpo extraño, tanto de forma inmediata como mediata, teniendo una conducta responsable ante la sospecha fundamentada de que ocurrió un accidente de esta naturaleza.

Within the scope of pediatric medical practice, certain situations arise where timely diagnosis of a condition implies facing unforeseen situations. Clinical history is clearly paramount for the correct and precise handling of any patient, even more so for very young patients from whom obtained data can be frequently imprecise. With respect to foreign body aspiration accidents, there are specific indicators which substantiate a suspicion of that case. Nevertheless, not all cases are typical, therefore, experience of the clinical operator is essential. The present study presents the case of a one year and nine months old patient who broncho-aspirated a chrome-steel crown in a dental practice, and the situation was only diagnosed 60 days later. The present diagnosis was emitted at once when the patient arrived at the National Pediatrics Institute. To that aim, a thorax X-ray was taken. The present case can be considered a paradigm. It supports the idea that the oral cavity of very young patients must be treated by qualified specialists, and that such care must be given in centers which can guarantee the patient's safety. A foreign body can remain in the bronchii for a long time, without directly endangering the patient's life. Nevertheless, this situation would introduce the patient into a dangerous chronicity, therefore, emergency room physicians should be aware of the possibility of a substantiated suspicion of foreign body aspiration. These cases, after suitable history research and auscultation could have been avoided, and thus avoid a serious chronic situation in these patients.

Evaluación de un sistema de medio fijo como soporte para una película microbiana capaz de reducir Cr (VI) de lodos residuales de curtiembres / Evaluation of a system of fixed media support for a film capable of reducing microbial Cr (VI) of tannerysewage sludge

El objetivo de esta investigación fue implementar un método microbiológico que permita reducir las concentraciones de cromo (VI) de lodos residuales provenientes de curtiembres mediante la combinación de procesos de ingeniería ambiental y microbiología. Se empleó un sistema de medio fijo que contenía un soporte de plástico al cual se adhiere la lama de microorganismos que realiza el proceso de purificación bajo condiciones físicas controladas, esto es demostrado in vivo con mediciones de cromo VI por absorción atómica del efluente tratado e in vitro mediante aislamiento e identificación de los microorganismos en medios de cultivo selectivos con K2CrO4. Los resultados demuestran una reducción de Cr (VI) del 58% por parte de los microorganismos: Bacillus cereus, Acinetobacter iwoffi, Lactobacillus agilis, Penicillium sp. y Cladosporium sp. capaces de tolerar concentraciones de 300 ppm de Cr (VI).

The goal of this research was to implement a microbiological method to reduce the concentrations of chromium (VI) of sewage sludge from tanneries through the combination of processes of environmental engineering and microbiology. A system of fixed medium was used, it contained a plastic support to which the lama of microorganisms adheres, performing the purification process under controlled physical conditions, this is demonstrated in vivo with measurements of chromium VI by atomic absorption of treated effluent and in vitro by isolation and identification of microorganisms in selective culture media with K2CrO4. The results show a 58% Cr (VI) reduction of the microorganisms: Bacillus cereus, Acinetobacter iwoffi, Lactobacillus agilis, Penicillium sp. and Cladosporium sp. Which are able to tolerate Cr (VI) concentrations of 300 ppm.

Yeast identification in routine clinical microbiology laboratory and its clinical relevance.

Rapid identification of yeast infections is helpful in prompt appropriate antifungal therapy. In the present study, the usefulness of chromogenic medium, slide culture technique and Vitek2 Compact (V2C) has been analysed. A total of 173 clinical isolates of yeast species were included in the study. An algorithm to identify such isolates in routine clinical microbiology laboratory was prepared and followed. Chromogenic medium was able to identify Candida albicans, C. tropicalis, C. krusei, C. parapsilosis and Trichosporon asahii. Chromogenic medium was also helpful in identifying "multi-species" yeast infections. The medium was unable to provide presumptive identification of C. pelliculosa, C. utilis, C. rugosa, C. glabrata and C. hemulonii. Vitek 2 compact (V2C) differentiated all pseudohypae non-producing yeast species. The algorithm followed was helpful in timely presumptive identification and final diagnosis of yeast infections, including multi-species yeast infections.

Tratabilidad del efluente de una tenería con presencia de cromo usando un reactor por carga secuencial / Tratability of Tannery Wastewater in the Presence of Chromium Usinga Sequencing Batch Reactor

Los efluentes industriales de las tenerías son altamente contaminantes por las elevadas concentraciones de materia orgánica, nitrógeno y metales pesados como el cromo que contienen. Los sistemas biológicos no convencionales, en especial los que usan reactores por carga secuencial (SBR) han demostrado ser una buena opción de tratamiento de estos efluentes por su flexibilidad y eficiencia en presencia de sustancias inhibidoras, tales como el cromo. El objetivo de esta investigación fue evaluar la eficiencia de un SBR en cuanto a la remoción de materia orgánica, nutrientes y metales pesados utilizando una mezcla de dos de las fracciones de los vertidos de una tenería (curtido con cromo y teñido). Se compararon las eficiencias de remoción obtenidas al alimentar el reactor con afluentes diluidos y concentrados, variando el tiempo de residencia hidráulica en 8 y 12 horas. Durante el tiempo de reacción se combinaron fases anóxicas y óxicas. Se obtuvo que las remociones de contaminantes fueron estadísticamente mayores cuando se usaron afluentes diluidos (DQO£1000 mg/L y [Cr3+]£10 mg/L), independientemente del tiempo de retención utilizado, lográndose la mayor eliminación durante la fase anóxica. Las remociones no mostraron diferencia estadística entre ellas, oscilando para los tratamientos con afluentes diluidos entre 82,5 y 84,2% para la DQO; 58,0 y 73,9% para P-PO4(3-) y 51,2 y 53,9% para el Cr. La eliminación de nitrógeno se realizó por asimilación debido a que los microorganismos nitrificantes fueron más sensibles e inhibieron su actividad frente a la presencia del cromo y altas concentraciones de materia orgánica. La remoción de cromo se logró por precipitación y/o adsorción en el lodo, por lo que fue fundamental controlar el pH en los reactores entre 7,5 y 8,5 unidades.

Tannery wastewater are highly pollutant for the high concentrations of organic matter, nitrogen and heavy metals as chrome that they contain. Sequential batch reactors (SBR) have demonstrated to be a good option of treatment of these effluents due to their flexibility and efficiency in presence of inhibiting substances (chrome). The aim of this investigation was to determine the best conditions for removal of organic matter, nutrients and heavy metals of the residual water of a tannery using a SBR fed on a mixture of tanning-dyeing effluent. The efficiencies of removal were compared when using dilute and concentrated influents, under 8 and 12 hour of hydraulic residence time. During the reaction phases anoxics and oxics phases were combined. The removal of pollutants were significantly higher when dilute influent was used (DQO£1000 mg/L and [Cr3+]£10 mg/L), independently of the retention time, being achieved the major elimination during the anoxic phase. The removals fluctuated between 82.5 and 84.45% of DQO, 58.0 and 73.9% of P-PO4(3-) and 51.2 and 53.9% of Cr. The elimination of nitrogen was achieved by assimilation, due to the fact that nitrifying bacteria were more sensitive and their activity was inhibited by the presence of chrome and high concentrations of organic matter. The removal of chrome was achieved by precipitation and/or adsorption on the sludge, being necessary to control the pH between 7.5 - 8.5 in the reactors.

Asas metálicas calibradas para microbiólogos: Una alternativa de fabricación nacional / Calibrated metallic loops for microbiologists: A nationally manufactured alternative

Las asas calibradas para la cuantificación de unidades formadoras de colonias bacterianas transfieren un volumen de muestra “exactamente conocido” y han sido herramientas de gran importancia para laboratorios de control de calidad, investigación y clínico. Las asas que se comercializan en el país son importadas y mayoritariamente de aleaciones de níquel-cromo. Es por ello que surge la necesidad de buscar internamente alternativas de bajo costo. En este trabajo se propuso la fabricación de asas con alambres comerciales de níquel-cromo equivalentes a las asas de platino y níquel-cromo comerciales, a un costo inferior. Las asas fueron comparadas según su desempeño y apariencia. Todas las asas fueron calibradas empleando dos métodos (gravimétrico y colorimétrico) con ángulos de carga de 45º y 90°. Se empleó un diseño experimental con arreglo factorial de tratamiento 2³ (método de calibración-tipo de asa-ángulo de carga, con 4 repeticiones). Se realizaron análisis de varianza de 672 datos, comparación de medias (prueba de Tukey) y se calcularon los intervalos de confianza de Bonferroni de las desviaciones estándar. Se demostró que las asas artesanales emulan a las comerciales, representando una alternativa nacional de bajo costo para la obtención de estos instrumentos.

Calibrated metallic loops for the quantification of bacterial colony forming units transfer an “exactly known” sample volume and have been extremely important tools for quality control, research and clinical laboratories. The loops marketed in our country are imported and mostly made of nickel-chrome alloy. This has created the need for searching for low cost national alternatives. In this work we propose the manufacture of these loops with commercial nickel-chrome wire equivalent to the commercial platinum and nickel-chrome loops, at lower costs. The loops were comparable in performance and appearance. All the loops were calibrated using two methods (gravimetric and colorimetric) with 45º and 90º charge angles. An experimental design with factorial treatment arrangement 2³ (calibration method-loop type-charge angle with 4 repetitions) was used. A 672 data variance analysis and comparison of means (Tukey’s test) were carried out, and Bonferroni’s confidence intervals of the standard deviations were calculated. It was demonstrated that the artisan loops emulated the commercial ones, representing a low cost national alternative for obtaining these instruments.

Perfuração dos lóbulos das orelhas como fator de risco para o desenvolvimento de alergia de contato ao níquel / Ear piercing as a risk factor for contact allergy to nickel

OBJETIVOS: Determinar a prevalência da alergia de contato aos metais em crianças que frequentam um centro de saúde e caracterizar o subgrupo com alergia em relação aos fatores de risco. MÉTODOS: Estudo transversal não controlado, conduzido em um centro de saúde de Belo Horizonte (MG). Foram incluídas crianças com idades entre 0 e 12 anos que se apresentaram para consulta pediátrica de rotina, sendo aplicados testes de contato para o cromo, o cobalto e o níquel. As análises estatísticas foram realizadas com base na leitura do teste em 96 horas. Leituras classificadas como fraca (+), forte (++) ou extrema (+++) foram consideradas como reação, enquanto as classificadas como duvidosa, negativa ou irritativa foram consideradas como não reação. RESULTADOS: Completaram o estudo 144 crianças. Destas, 4,9 por cento apresentaram reação ao cromo, 9,7 por cento ao cobalto e 20,1 por cento ao níquel. Os pacientes com orelha perfurada tiveram mais chance de reação ao níquel do que aqueles sem essa característica (p = 0,031 e odds ratio = 2,8). CONCLUSÕES: Em face da tendência atual ao aumento da alergia ao níquel, familiares devem ser alertados sobre a sua associação com a perfuração das orelhas. Estudos posteriores são necessários para avaliar a idade ideal para a perfuração das orelhas e o material ideal para brincos.

OBJECTIVES: To determine the prevalence of metal contact allergy among the children seen at a health center and to characterize children with metal allergies in terms of risk factors. METHODS: This was an uncontrolled cross-sectional study undertaken at a health center in Belo Horizonte, Brazil. Children aged from 0 to 12 years were recruited when they presented at the health center for routine pediatric consultations and were given contact tests for chrome, cobalt and nickel. Statistical analyses were conducted on test readings taken at 96 hours. Results classed as weak (+), strong (++) or extreme (+++) were defined as "reaction," while those classed as doubtful, negative or irritant were defined as "no reaction." RESULTS: A total of 144 children completed the study protocol. Of these, 4.9 percent exhibited a reaction to chrome, 9.7 percent to cobalt and 20.1 percent to nickel. Patients with pierced ears were more likely to react to nickel than those without pierced ears (p = 0.031 and odds ratio = 2.8). CONCLUSIONS: In view of the current tendency for the prevalence of nickel allergy to increase, parents should be warned about its association with ear piercing. Further studies are needed to determine the ideal age for ear piercing and the ideal materials for earrings.

Quantificação de minerais em sucos industrializados / Measurement of minerals inprocessed juices

Os sucos de frutas são considerados como uma boa opção de fonte de minerais e vitaminas. O consumo de sucos de frutas industrializados cresceu muito no Brasil, principalmente aqueles envasados em embalagens cartonadas da Tetra Pak®. Para avaliar o teor de minerais em sucos industrializados, foram analisadas as quantidades de sete metais (Zn, Ni, Pb, Fe, Cu, Cr e Na) em sucos de uva e pêssego (integral e light). Os minerais foram extraídos por meio da digestão com ácido clorídrico, e detectados por espectrofotometria de absorção atômica com atomização em chama. Não foram detectadas em quantidades significativas a presença dos metais Zn, Ni, Pb e Cu nos sucos. No entanto, Na, Cr e Fe foram detectados, sendo que o Cr apresentou uma concentração maior que a permitida pelas especificações da ANVISA (Agência Nacional de Vigilância Sanitária), indicando uma possível contaminação destes produtos. Vale ressaltar que o suco light de pêssego foi o que apresentou os maiores teores de ferro.

The fruit juices are considered a good option as a source of minerals and vitamins. The consumption of fruit juices has grown industrialized in Brazil, especially those packaged in cartons from Tetra Pak ®. To evaluate the content of minerals in industrialized juices were analyzed amounts of seven metals (Zn, Ni, Pb, Fe, Cu, Cr and Na) in grape juice and peach juice (integral and light). The minerals were extracted by digestion with hydrochloric acid, and detected by atomic absorption spectrometry with flame atomization. It was not detected in significant amounts to the presence of the metals Zn, Ni, Pb and Cu in the juices. However Na, Cr and Fe were detected, and Cr showed a higher concentration than allowed by the specifications of ANVISA (Agência Nacional de Vigilância Sanitária), indicating a possible contamination of these products. It is interesting to say that light peach juice showed the highest levels of iron.

An Occupational Chrome Ulcer / 대한피부과학회지

Chrome may have a corrosive, necrotizing effect on tissue, so repeated skin contact to chromate might induce perforations or ulcers on the skin. This condition is called a "chrome ulcer" or "chrome hole". It appears as a small, punched-out mark with a rolled-out border. It is rarely associated with pain, but a severe itching sensation is common. We report a case of a 33-year-old man who presented with a 3 month history of several ulcers on his abdomen. He was employed at a chromate alloying process. He had several hole-like atrophic scars and unbearable pruritus. After changing his occupation, plus treatment with oral corticosteroids and antihistamines, the lesions were healed and the itching sensation faded away. However, atrophic scarring remained.

Minimum 4 Year Follow-up Results of Metalon Metal Hip Resurfacing Arthroplasty / 대한정형외과학회잡지

PURPOSE: To report the minimum 4 year follow up results of metal on metal hip resurfacing arthroplasty. MATERIALS AND METHODS: 39 hips from 36 patients, who received hip resurfacing from November 1998 to September 2001 and were followed up for at least 4 years, were enrolled in this study. The average age was 45 years (28-69 years) and the average follow up period was 51.9 months (48-82 months). A clinical evaluation was performed with the Harris Hip Score and gait analysis postoperatively. A radiologic evaluation was performed regularly after surgery using anteroposterior and lateral simple radiographs. The post-operative cobalt-chrome serum concentration was measured and compared using 21 cases of ceramic-on-ceramic total hip arthroplasty as a control group. RESULTS: The Harris Hip Score improved from 61 points (31-74) preoperatively to 96 points (85-99) postoperatively. There were no cases of acetabular loosening, and the average angle of femoral insert to the shaft was 136 degrees with 22 hips (61.1%) being within 130-140 degrees. The 4 year follow-up survival rate was 97.4%. The serum cobalt and chrome levels were higher than the control group (p<0.05). CONCLUSION: Hip resurfacing showed excellent survival rate after a short-term follow-up, but still requires a long-term evaluation with more cases and further metal ion release studies.

Clinical Observation of Cellular Phone Dermatitis in Korea / 대한피부과학회지

BACKGROUND: Recently, the use of cellular phones has greatly increased, and allergic contact dermatitis (ACD) ascribed to the use of cellular phones has been one of the problems. OBJECTIVE: The purpose of this study was to evaluate clinical characteristics of allergic contact dermatitis due to cellular phone use. METHODS: Three male and 7 female patients who were diagnosed as ACD due to cellular phone use were evaluated. A patch test was performed on the upper back and any history of metal allergy was checked. We also evaluated the content of nickel in the cellular phones currently being sold on the market, using a dimethylglyoxime spot test. RESULTS: The results of this study are summarized as follows; There was female predominance in cellular phone dermatitis with an average onset of age 27.4 years old. A history of metal allergy was found in 40.0% of the patients. The most common site and mobile phone type were cheek (60.0%) and slider type (60.0%), respectively. In addition to erythematous patches, itching was accompanied in 60.0% of the patients. But the other patients did not report any pruritus at all. Except in three cases, patch tests were performed on the upper back. Five patients were positive to nickel and 4 patients were positive to chrome. The dimethylglyoxime test showed 21.2% positivity in 104 cellular phones of 27 different models. CONCLUSION: Cellular phone dermatitis usually occurs on both cheeks, or the dominant hand-sided cheek area. The causative metals are mostly nickle and chrome.

Two Cases of Cellular Phone Dermatitis / 대한피부과학회지

In recent years, cellular phones have become one of lifes necessities. In proportion to the number of cellular phones in use, the number of reported cellular phone dermatitis cases has increased. Chromate and nickel sulfate are thought to be the allergen of cellular phone dermatitis, but direct qualitative analysis of cellular phones has not yet been carried out. We report 2 cases of cellular phone dermatitis which were suspected to be caused by a contact allergy to nickel. Patch tests were performed and showed a positive reaction to cobalt chloride and nickel sulfate. Direct qualitative analysis by a scanning electron microscope-energy dispersive X-ray analyzer of the cellular phones of the patients showed peaks for nickel and chrome.