Conservação de peças anatômicas em cloreto de sódio: um estudo com produto de fecundação / Conservation of anatomical parts in sodium chloride: a study with fertilization product / Conservación de partes anatómicas en cloruro sódico: un estudio con producto de fertilización

Introdução: Os materiais de origem humana geralmente são conservados em formaldeído, para possibilitar o estudo da anatomia humana, tal conservante possui baixo custo e boa fixação, contudo é toxico. Diante do exposto é necessário, o estudo de outros métodos de conservação, menos prejudiciais, como a solução de NaCl 30%. Objetivo: Comparar a conservação de peças anatômicas em solução de NaCl à 30% e formaldeído a 10%. Método: Pesquisa experimental, exploratória e descritiva, realizada com dois produtos de abortamento, no laboratório de anatomia de uma universidade pública, no estado do Paraná/BR. Foi realizada fixação em solução de formol 10%, em seguida uma amostra foi lavado em água corrente e armazenado em solução de NaCl à 30%. Após 6 meses da conservação em solução salina, foram coletadas amostras, estas foram submetidas a análise de crescimento bacteriano. Avaliou-se tonalidade e turgor cutâneo, odor e peso, bem como crescimento bacteriano. O estudo seguiu os preceitos éticos (CAAE: 53740121.9.0000.9247). Resultados: Foram realizadas observações após 24h, 7, 30, 60, 90 e 180 dias. O feto em solução de NaCl não possui odor, e diminuição do turgor da pele. Ambas a amostras não apresentaram crescimento bacteriano. Considerações finais: A solução de NaCl a 30% desidrata a pele, mas não altera significativamente a forma e estrutura, ainda não possui odor e nem toxicidade, o que garante benefícios a saúde de quem os manipula, bem como tal concentração de NaCl inibe de forma efetiva o crescimento bacteriano nos tecidos e na própria solução, se demostrando eficaz na conservação.

Introduction: The materials of human origin are usually preserved in formaldehyde, to enable the study of human anatomy, this preservative has low cost and good fixation, however it is toxic. Therefore, it is necessary to study other less harmful preservation methods, such as 30% NaCl solution. Objective: To compare the preservation of anatomical specimens in 30% NaCl solution and 10% formaldehyde solution. Method: Experimental, exploratory and descriptive research, carried out with two abortion products, in the anatomy laboratory of a public university, in the state of Paraná/BR. Fixation in 10% formaldehyde solution was performed, after which a sample was washed in running water and stored in a 30% NaCl solution. After 6 months of preservation in saline solution, samples were collected and submitted to bacterial growth analysis. Skin tone and turgor, odor, weight, and bacterial growth were evaluated. The study followed the ethical precepts (CAAE: 53740121.9.0000.9247). Results: Observations were made after 24h, 7, 30, 60, 90 and 180 days. The fetus in NaCl solution had no odor, and decreased skin turgor. Both samples showed no bacterial growth. Final considerations: The 30% NaCl solution dehydrates the skin, but does not alter significantly the shape and structure, and also has no odor or toxicity, which guarantees health benefits to those who handle them, and such concentration of NaCl inhibits effectively the bacterial growth in the tissues and in the solution itself, proving to be effective in conservation.

Introducción: Los materiales de origen humano suelen conservarse en formol, para posibilitar el estudio de la anatomía humana, este conservante tiene bajo coste y buena fijación, sin embargo es tóxico. Por ello, es necesario estudiar otros métodos de conservación menos nocivos, como la solución de NaCl al 30%. Objetivo: Comparar la conservación de especímenes anatómicos en solución de NaCl al 30% y en solución de formaldehído al 10%. Método: Investigación experimental, exploratoria y descriptiva, realizada con dos abortos, en el laboratorio de anatomía de una universidad pública, en el estado de Paraná/BR. Fue realizada fijación en solución de formaldehído al 10%, después de lo cual la muestra fue lavada en agua corriente y almacenada en solución de NaCl al 30%. Tras 6 meses de conservación en solución salina, se recogieron las muestras y se sometieron a análisis de crecimiento bacteriano. Se evaluaron el tono y la turgencia de la piel, el olor, el peso y el crecimiento bacteriano. El estudio siguió los preceptos éticos (CAAE: 53740121.9.0000.9247). Resultados: Las observaciones se realizaron después de 24h, 7, 30, 60, 90 y 180 días. El feto en solución de NaCl no tenía olor, y la turgencia de la piel disminuyó. Ambas muestras no mostraron crecimiento bacteriano. Consideraciones finales: La solución de NaCl al 30% deshidrata la piel, pero no altera significativamente la forma y estructura, además no tiene olor ni toxicidad, lo que garantiza beneficios para la salud de quienes los manipulan, y dicha concentración de NaCl inhibe eficazmente el crecimiento bacteriano en los tejidos y en la propia solución, demostrando ser eficaz en la conservación.

Effect of a calcium hydroxide-based intracanal medicament containing N-2-methyl pyrrolidone as a vehicle against Enterococcus faecalis biofilm

Abstract This study investigated the effect of a calcium hydroxide (CH) paste (CleaniCal®) containing N-2-methyl pyrrolidone (NMP) as a vehicle on Enterococcus faecalis (E. faecalis) biofilms compared with other products containing saline (Calasept Plus™) or propylene glycol (PG) (Calcipex II®). Methodology Standardized bovine root canal specimens were used. The antibacterial effects were measured by colony-forming unit counting. The thickness of bacterial microcolonies and exopolysaccharides was assessed using confocal laser scanning microscopy. Morphological features of the biofilms were observed using field-emission scanning electron microscopy (FE-SEM). Bovine tooth blocks covered with nail polish were immersed into the vehicles and dispelling was observed. The data were analyzed using one-way analysis of variance and Tukey tests (p<0.05). Results CleaniCal® showed the highest antibacterial activity, followed by Calcipex II® (p<0.05). Moreover, NMP showed a higher antibacterial effect compared with PG (p<0.05). The thickness of bacteria and EPS in the CleaniCal® group was significantly lower than that of other materials tested (p<0.05). FE-SEM images showed the specimens treated with Calasept Plus™ were covered with biofilms, whereas the specimens treated with other medicaments were not. Notably, the specimen treated with CleaniCal® was cleaner than the one treated with Calcipex II®. Furthermore, the nail polish on the bovine tooth block immersed in NMP was completely dispelled. Conclusions CleaniCal® performed better than Calasept Plus™ and Calcipex II® in the removal efficacy of E. faecalis biofilms. The results suggest the effect might be due to the potent dissolving effect of NMP on organic substances.

Efeitos da qualidade da carne suína na cor e textura instrumentais de lombos defumados com teor reduzido de sal / Pork quality effects on instrumental color and texture of smoked loins with reduced salt contente

Objetivou-se avaliar os efeitos da qualidade da carne suína (PFN, PSE, RFN, RSE e DFD) e do teor de sal (1,2 e 1,8%) nos valores de perda por cozimento (PPC), pH e cor e textura instrumentais de lombos marinados, curados e defumados. Não houve efeito significativo (P>0,05) para os valores de PPC (10,85 ± 3,98%), pH (6,24 ± 0,32) e todos os índices de cor avaliados (L* = 64,47 ± 3,29; C* = 13,68 ± 2,58; e h = 55,05 ± 5,30°). No entanto, a dureza e a coesividade foram menores nos produtos adicionados com 1,8% de sal, enquanto a mastigabilidade foi afetada pela interação entre teor de sal e qualidade da carne. Conclui-se que os uso de diferentes classes de qualidade e teores de sal na elaboração de lombos defumados não afeta o rendimento e coloração dos produtos, mas ambos os fatores afetam significativamente a textura final.

Effect of post-space irrigation with naocl and caocl at different concentrations on the bond strength of posts cemented with a self-adhesive resin cement

Abstract The aim of this study was to evaluate the effect of post-space irrigation with NaOCl and CaOCl at different concentrations on the bond strength of posts cemented with a self-adhesive resin cement. Eighty premolars were sectioned 14 mm from the apex, and endodontically treated. The root canal filling was partially removed. Specimens were randomly assigned into 8 groups (n=10), according to the irrigant for post-space irrigation: SS - 0.9% saline solution (control group); CHX - 2% chlorhexidine; 1% NaOCl - 1% sodium hypochlorite; 2.5% NaOCl - 2.5% sodium hypochlorite; 5% NaOCl - 5% sodium hypochlorite; 1% CaOCl - 1% calcium hypochlorite; 2.5% CaOCl - 2.5% calcium hypochlorite; and 5% CaOCl - 5% calcium hypochlorite. For each group, irrigation was performed continuously with 2 ml of solution. The post-spaces were dried with paper points (#80), and glass fiber posts were cemented using a self-adhesive resin cement. The specimens were sectioned perpendicularly and the push-out test was performed. Optical microscopy was used to analyze the failure mode. ANOVA and Bonferroni tests analyzed the bond strength data. NaOCl and CaOCl presented similar bond strength regardless the concentration used to irrigate the post-space (p>0.05). SS showed the highest bond strength (11.47 MPa) (p<0.05). Adhesive failures at the cement/dentin interface were predominant (58.33%). Saline solution should be irrigant of choice to irrigate the post-space before fiber post cementation with self-adhesive resin cement. NaOCl and CaOCl negatively affect the bond strength values.

Resumo O objetivo deste estudo foi avaliar o efeito da irrigação do espaço preparado para o pino com NaOCl e CaOCl em diferentes concentrações na resistência adesiva de pinos cimentados com um cimento resinoso autoadesivo. Oitenta pré-molares foram seccionados 14 mm do ápice e endodonticamente tratado. As obturações foram parcialmente removidas. Os espécimes divididos randomicamente em 8 grupos (n=10) de acordo com o irrigante usado para irrigação do espaço preparado para pino: SF - soro fisiológico 0,9% (grupo controle); CHX - clorexidina 2%; NaOCl 1% - hipoclorito de sódio 1%; NaOCl 2,5% - hipoclorito de sódio 2,5%; NaOCl 5% - hipoclorito de sódio 5%; CaOCl 1% - hipoclorito de cálcio 1%; CaOCl 2,5% - hipoclorito de cálcio 2,5%; CaOCl 5% - hipoclorito de cálcio 5%. Para cada grupo, irrigação foi realizada com 2 mL de solução. O espaço preparado para pino foi seco com cone de papel absorvente (#80) e os pinos de fibra foram cimentados com cimento resinoso autoadesivo. Os espécimes foram seccionados perpendicularmente e o teste de push-out foi realizado. Microscopia óptica foi usada para analisar o padrão de falha. Os testes de ANOVA e Bonferroni analisaram os dados de resistência adesiva. NaOCl e CaOCl apresentaram similar resistência adesiva, independentemente da concentração usada para irrigar o espaço preparado para pino (p>0,05). SF apresentou os maiores valores de resistência adesiva (11,47 MPa) (p<0,05). Falhas adesivas na interface cimento/dentina foram predominantes (58,33%). Soro fisiológico deve ser o irrigante de escolha para irrigar o espaço preparado para pino antes da cimentação de pinos de fibra com cimentos resinosos autoadesivos. NaOCl e CaOCl afetam negativamente os valores de resistência adesiva.

Fluoride concentrations in salt marketed in Managua, Nicaragua

Abstract Nicaraguan legislation has established that fluoride concentrations in salt should be 200-225 mg/kg, but no report describes fluoride concentrations in salt marketed in this country. We evaluated the fluoride concentrations in 33 packages of salt of 11 brands (n = 3 each) purchased in Managua, Nicaragua. According to the package information, 9 of the 11 brands were fluoridated. Six aliquots of each package were weighed (mean 2.5 ± 0.3 g; n = 198) and dissolved in 0.025 g/ml water. Duplicates of 1.0 ml of solutions prepared were buffered (1:1; v/v) with TISAB II. Fluoride concentrations were determined with ion-specific electrode, calibrated with standard solutions (0.25-16.0 μg F/ml) mixed (1:1; v/v) with TISAB II added to 0.025 g (p.a.) NaCl/ml. The mean (± standard deviation, n = 3) fluoride concentrations of two fluoridated brands were in accord with Nicaraguan law (209.8 ± 48.0 and 211.4 ± 26.0 mg F/kg), and those of five brands were below the mandated range (131.0 ± 34.3, 180.6 ± 12.3, 184.6 ± 34.8, 190 ± 47.2, and 199.0 ± 18.9 mg F/kg); two brands contained only traces of fluoride. The two non-fluoridated brands had traces of fluoride. The findings show that the surveillance system for the salt fluoridation program in Nicaragua should be improved, as most salt analyzed violated the requirements of the national legislation.

Purification of inulinases by changing the ionic strength of the medium and precipitation with alcohols

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.

A titration model for evaluating calcium hydroxide removal techniques

Objective Calcium hydroxide (Ca(OH)2) has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical challenges with endodontic treatment. This study used a chemical titration method to measure residual Ca(OH)2 left after different endodontic irrigation methods. Material and Methods Eighty-six human canine roots were prepared for obturation. Thirty teeth were filled with known but different amounts of Ca(OH)2 for 7 days, which were dissolved out and titrated to quantitate the residual Ca(OH)2 recovered from each root to produce a standard curve. Forty-eight of the remaining teeth were filled with equal amounts of Ca(OH)2 followed by gross Ca(OH)2 removal using hand files and randomized treatment of either: 1) Syringe irrigation; 2) Syringe irrigation with use of an apical file; 3) Syringe irrigation with added 30 s of passive ultrasonic irrigation (PUI), or 4) Syringe irrigation with apical file and PUI (n=12/group). Residual Ca(OH)2 was dissolved with glycerin and titrated to measure residual Ca(OH)2 left in the root. Results No method completely removed all residual Ca(OH)2. The addition of 30 s PUI with or without apical file use removed Ca(OH)2 significantly better than irrigation alone. Conclusions This technique allowed quantification of residual Ca(OH)2. The use of PUI (with or without apical file) resulted in significantly lower Ca(OH)2 residue compared to irrigation alone. .

Breast cancer in Latin America: global burden, patterns, and risk factors / Cáncer de mama en América Latina: carga, patrones y factores de riesgo

Breast cancer is a major public health problem in Latin America (LA) and the most common form of cancer among women. An important variability according to ethnicity/race with respect to incidence/mortality, clinical characteristics, and prognosis is observed throughout LA. In addition, women are more likely to develop breast cancer (BC) at younger age and to be diagnosed at an advanced stage compared to western women. While little is known about specific risk factors, changes in reproductive pattern (parity, breastfeeding) and lifestyle factors including sedentary behaviours, unhealthy diet, and alcohol intake may contribute to the increase of BC incidence. In this paper we give an overview of the burden and patterns of BC, review the leading causes of BC and discuss the possible ways to improve BC prevention and control in LA.

El cáncer de mama (CaMa) es uno de los mayores problemas de salud pública en América Latina (AL) y el cáncer más frecuente en mujeres. Se observa una importante variabilidad en la incidencia/mortalidad, las características clínicas y el pronóstico según la etnia/raza a lo largo de AL. Además, las mujeres latinoamericanas son más propensas a desarrollar CaMa en edades más tempranas y a ser diagnosticadas en una etapa más avanzada, comparando con mujeres occidentales. Aunque poco se sabe sobre sus factores de riesgo específicos, cambios en los patrones reproductivos (paridad y lactancia) y estilos de vida, incluyendo los hábitos sedentarios, las dietas poco saludables y el consumo de alcohol, podrían contribuir al incremento de la incidencia del CaMa. En este artículo se da una visión general de la carga y los patrones del CaMa, se revisan las causas principales del CaMa y se discuten posibles vías para mejorar la prevención y el control del CaMa en AL.

Corrosion behavior of self-ligating and conventional metal brackets

Objective: To test the null hypothesis that the aging process in self-ligating brackets is not higher than in conventional brackets. Methods: Twenty-five conventional (GN-3M/Unitek; GE-GAC; VE-Aditek) and 25 self-ligating (SCs-3M/Unitek; INs-GAC; ECs-Aditek) metal brackets from three manufacturers (n = 150) were submitted to aging process in 0.9% NaCl solution at a constant temperature of 37 ± 1ºC for 21 days. The content of nickel, chromium and iron ions in the solution collected at intervals of 7, 14 and 21 days was quantified by atomic absorption spectrophotometry. After the aging process, the brackets were analyzed by scanning electron microscopy (SEM) under 22X and 1,000X magnifications. Results: Comparison of metal release in self-ligating and conventional brackets from the same manufacturer proved that the SCs group released more nickel (p < 0.05) than the GN group after 7 and 14 days, but less chromium (p < 0.05) after 14 days and less iron (p < 0.05) at the three experimental time intervals. The INs group released less iron (p < 0.05) than the GE group after 7 days and less nickel, chromium and iron (p < 0.05) after 14 and 21 days. The ECs group released more nickel, chromium and iron (p < 0.05) than the VE group after 14 days, but released less nickel and chromium (p < 0.05) after 7 days and less chromium and iron (p < 0.05) after 21 days. The SEM analysis revealed alterations on surface topography of conventional and self-ligating brackets. Conclusions: The aging process in self-ligating brackets was not greater than in conventional brackets from the same manufacturer. The null hypothesis was accepted. .

Objetivo: testar a hipótese nula de que o processo de envelhecimento em braquetes autoligáveis não é superior ao de braquetes convencionais. Métodos: Vinte e cinco braquetes metálicos convencionais (GN, 3M/Unitek; GE, GAC; VE, Aditek) e 25 autoligáveis (SCs, 3M/Unitek; INs, GAC; ECs, Aditek) de três fabricantes (n = 150) foram submetidos ao envelhecimento em solução de NaCl à temperatura constante de 37 ± 1ºC, durante 21 dias. O conteúdo de íons níquel, cromo e ferro na solução coletada com 7, 14 e 21 dias foi quantificado por meio de espectrofotometria de absorção atômica. Depois de completado o processo de envelhecimento, os braquetes foram analisados com microscópio eletrônico de varredura (MEV), em magnificações de 22x e de 1.000x. Resultados: comparando-se a liberação de metais por braquetes autoligáveis e convencionais do mesmo fabricante, observou-se que o grupo SCs liberou mais níquel (p < 0,05) que o grupo GN após 7 e 14 dias, mas menos cromo (p < 0,05) após 14 dias e menos ferro (p < 0,05) nos três períodos experimentais. O grupo INs liberou menos ferro (p < 0,05) que o grupo GE após 7 dias, e menos níquel, cromo e ferro (p < 0,05) após 14 e 21 dias. O grupo ECs liberou mais níquel, cromo e ferro (p < 0,05) que o grupo VE após 14 dias; entretanto, liberou menos níquel e cromo (p < 0,05) após 7 dias e menos cromo e ferro (p < 0,05) após 21 dias. A análise no MEV demonstrou alterações na topografia da superfície de braquetes convencionais e autoligáveis. Conclusões: o processo de envelhecimento em braquetes autoligáveis não foi superior ao de braquetes convencionais do mesmo fabricante. A hipótese nula está aceita. .

Sal y salud: avances en conocimientos, acciones y propuestas / Salt and health: progess in knowledge, actions and proposals / Sal e saúde: avanços em conhecimentos, ações e propostas

En la Argentina y el mundo existen acciones tendientes a reducir la ingesta de sal; entre ellas, intervenciones de educación al consumidor y reducción del contenido de sal en alimentos procesados. Las Guías Alimentarias parala Población Argentina editadas en 2000 incluyen un mensaje específico destinado a orientar una ingesta que no supere los 6g diarios. El Foro de la Organización Mundial de la Salud s obre la Reducción del Consumo de Sal enla Población recomienda educar al consumidor y promover entornos que faciliten la elección de alimentos mássanos. Pocas investigaciones reflejan la ingesta de sal por parte de los consumidores; diversos estudios muestran que las personas tienen un deficiente reconocimiento de su ingesta de sal y no son plenamente conscientes de la relación “ingesta de s al-salud”. Las intervenciones preventivas más efectivas son las que involucran al consumidor desde su planificación, teniendo en cuenta los intereses, representaciones, preconceptos y posibilidades concretas de ejercer el autocuidado de las personas. Acciones sinérgicas entre el sector salud, la industriay las organizaciones de la sociedad civil para educar al consumidor y ofrecer entornos alimentarios más saludables redundarán en mayores y mejores resultados en la reducción de la ingesta de sal/sodio y su efecto perjudi-cial sobre la salud.

In Argentina and the world there is an effort to lower sal tintake, including consumer education and reduction of the salt content of processed foods. The Dietary Guidelines for Argentine Population published in 2000 specifically advise a maximum daily salt intake of 6 g.The World Health Organization Forum on Reducing Salt Intake in Populations recommends educating consumers and promoting environments that facilitate healthy food choices. There are not many investigations on the amount of salt consumers use, while several studies show that people have a poor recognition of their sal tintake and they are not fully aware of the relationship between salt intake and health. The most effective preventive interventions are those that involve consumer sat the very beginning of the planning process, taking into account their interests, representations, beliefs and their real possibilities of participating in their own care...

Na Argentina e no mundo existem ações tendentes areduzir a ingestão de sal; entre elas, intervenções deeducação ao consumidor e redução do conteúdo de salem a limentos processados. Os Guias Alimentícios para aPopulação Argentina editados em 2000 incluem umamensagem específica destinada a orientar uma ingestãoque não supere 6g diárias. O Foro da OrganizaçãoMundial da Saúde sobre a Redução do Consumo de Salna População recomenda educar o consumidor e promoverambientes que facilitem a escolha de alimentos maissaudáveis. Poucas pesquisas refletem a ingestão d e salpor parte dos consumidores; diversos estudos mostramque as pessoas têm um deficiente reconhecimento dasua iconscientes da relação “ingestão de sal – saúde”. Asintervenções preventivas mais efetivas são as queenvolvem o consumidor desde o seu planejamento,tendo em conta os intereses, representaconcebidos...

In vitro comparative evaluation of the effect of two different fiber reinforcements on the fracture toughness of provisional restorative resins.

Background: Fracture of provisional fixed partial denture (FPD) may jeopardize the success of provisional prosthodontic treatment phase and cause patient discomfort. Aim: The aim of this study was to compare the fracture toughness of the Polymethyl Methacrylate (PMMA) resin and Bis-Acryl Composite (BAC) resin reinforced with the Polyethylene and Glass fibers. Materials and Methods: Three groups (N=10) of each of the two materials were prepared for the fracture toughness test. Two groups had the different reinforcements and group without reinforcement served as the control. The mean fracture toughness (MPa.m½ ) was compared by One-way ANOVA, followed by the Scheffe analysis. Fracture toughness between fiber-reinforced PMMA and BAC resin was compared by the independent samples t test. Results: For the controls, the fracture toughness for PMMA resin (0.91) was significantly lower than for the BAC resin (1.19). Glass fiber reinforcement produced significantly higher fracture toughness for both, PMMA (1.48) and BAC (1.82) resin, but the Polyethylene fibers did not (0.95 for PMMA and 1.23 for BAC resin). Among the reinforced groups, Silane impregnated Glass fibers showed highest fracture toughness for the BAC resin (1.82). Conclusion: Of two fiber reinforcement methods evaluated, Glass fiber reinforcement for the PMMA and BAC resin produced highest fracture toughness. Clinical Implications: On the basis of this in--vitro study, the use of Glass and Polyethylene fibers tested may be an effective way to reinforce resins used to fabricate fixed provisional restorations.

Avaliação ultrassonográfica da tireoide, determinação da iodúria e concentração de iodo em sal de cozinha utilizado por escolares de Ribeirão Preto, São Paulo, Brasil / Ultrasonographic evaluation of the thyroid, determination of ioduria and iodine concentration in kitchen salt used by schoolchildren in Ribeirão Preto, São Paulo, Brazil

OBJETIVO E MÉTODOS: Estudos prévios apontaram Ribeirão Preto, São Paulo, como área de carência limítrofe de iodo e, posteriormente, de iodação excessiva. Reavaliando seu estado iódico em 2007-2008, foram analisados 300 escolares entre 8 e 10 anos de idade, procedentes de três escolas de diferentes níveis socioeconômicos e realizadas dosagens de iodo urinário e da concentração de iodo no sal doméstico e ultrassonografia tireoidiana. RESULTADOS E CONCLUSÃO: A iodúria foi superior na escola com maior nível socioeconômico, comparada às outras, e a diferença foi significante aos 8 e 10 anos para os meninos (p < 0,0001 e p = 0,0106, respectivamente) e aos 8 e 9 anos para as meninas (p = 0,0024 e p = 0,0154, respectivamente). As concentrações medianas de iodo em amostras de sal doméstico variaram entre 26,6 e 27,8 mg iodo/kg e não foram diferentes nas escolas estudadas. À ultrassonografia, 15,6 por cento das tireoides examinadas apresentaram-se hipoecoicas, sugerindo que elas possam apresentar mudanças em sua arquitetura sem ainda alterar seus volumes.

OBJECTIVE AND METHODS: Previous studies have pointed out that Ribeirão Preto, São Paulo, is an area of borderline iodine deficiency, later becoming a region of excessive iodination. In a reevaluation of the iodine status of the city in 2007-2008, 300 schoolchildren aged 8 to 10 years were evaluated, from 3 schools of 3 different socioeconomic levels who were submitted to the determination of iodine concentration in urine samples and in kitchen salt and thyroid ultrasound. RESULTS AND CONCLUSION: Among boys and girls ioduria was higher in the school of highest socioeconomic level compared to the others, with a significant difference in the ages 8 and 10 years for boys with ranges : p < 0,0001 and p = 0,0106, respectively; and in the ages 8 and 9 years for girls with ranges: p = 0,0024 and p = 0,0154, respectively. Median iodine concentrations in samples of kitchen salt ranged from 26.6 to 27.8 mg iodine/kg and did not differ between the schools studied. Ultrasound evaluation revealed that 15,6 percent of thyroids examined were hypoechoic, suggesting that these glands may present changes in the architecture not reflected yet in their volume.

Recovery of silver residues from dental amalgam

Dental amalgam residues are probably the most important chemical residues generated from clinical dental practice because of the presence of heavy metals among its constituents, mainly mercury and silver. OBJECTIVE: The purpose of this study was to develop an alternative method for the recovery of silver residues from dental amalgam. MATERIAL AND METHODS: The residue generated after vacuum distillation of dental amalgam for the separation of mercury was initially diluted with 32.5 percent HNO3, followed by precipitation with 20 percent NaCl. Sequentially, under constant heating and agitation with NaOH and sucrose, the sample was reduced to metallic silver. However, the processing time was too long, which turned this procedure not viable. In another sequence of experiments, the dilution was accomplished with concentrated HNO3 at 90ºC, followed by precipitation with 20 percent NaCl. After washing, the pellet was diluted with concentrated NH4OH, water and more NaCl in order to facilitate the reaction with the reducer. RESULTS: Ascorbic acid was efficiently used as reducer, allowing a fast reduction, thus making the procedure viable. CONCLUSIONS: The proposed methodology is of easy application and does not require sophisticated equipment or expensive reagents.

Novel multi-layer APPPA microcapsules for oral delivery: preparation condition, stability and permeability.

Oral therapy utilizing cell microencapsulation has shown promise in the treatment of many diseases. Current obtainable microcapsule membranes, however, show inadequate stability in the gastrointestinal (GI) environment, thus restricting the general application of live cells for oral therapy. To overcome this limitation, we have previously developed a novel multi-layer alginate/poly-L-lysine/pectin/poly-L-lysine/alginate microcapsule (APPPA) with demonstrated improvement on membrane stability over the frequently reported alginate/poly-L-lysine/alginate (APA) microcapsules. In this study, we further examined the effects of preparation conditions on microcapsule formation, and assessed the membrane strength and GI stability. Results showed that increased membrane strength of the APPPA microcapsules was attained by using pectin with low degree of esterification as the mid-layer material, saline as the solvent for the preparation solutions and washing medium, and 0.1 M CaCl2 as the gelling solution for alginate cores. Resistance of this membrane to the simulated GI fluids was also investigated. Permeability of and release profiles from the APPPA microcapsules were found comparable to the APA microcapsules. These findings suggested that the multi-layer APPPA microcapsule formulation may have potential in oral delivery of proteins, live bacterial cells and other biomedical applications.

Chromium (VI) tolerance in two halotolerant strains of Nostoc.

The present study reports on chromium (VI) tolerance of two cyanobacterial strains Nostoc linckia and Nostoc spongiaeforme isolated from salt affected soils using uni-algal and bi-algal systems. Besides distinct halophilism, the two strains exhibited remarkable tolerance to chromium (VI) and revealed 1.2 to 2.8 times more chlorophyll in the presence of the metal. While phycobilins and carotenoids also increased in Nostoc linckia with total dissolved salts (TDS) as well as metal, a decline was observed in Nostoc spongiaeforme in the presence of Cr (VI). Relative algal biomass (as % of control) showed significantly higher values (123-239) in Nostoc linckia in the presence of salt, metal and combination of the two. In Nostoc spongiaeforme it declined in the presence of metal (72-81) but increased in the presence of salts (143-249) and also in the binary systems (121-440). The bi-algal consortium showed relatively less tolerance to salt and metal stress. Nostoc linckia (20 day culture) showed upto 40% chromium removal whereas Nostoc spongiaeforme showed up to 12% removal, indicating greater suitability of the former for use in bioremediation studies.

Insufficient level of iodine content in household powder salt in Nepal.

Universal salt iodization (USI) is long term strategy for the control of iodine deficiency disorder (IDD) in Nepal. Standardized periodic testing of the iodine content in salt is a critical part of a salt iodisation programme. To achieve programmatic objective, this study was carried out to estimate the iodine content of household salt in Kavre, Lalitpur and Parsa districts of Nepal. Iodometric titration of 1803 salt samples collected from the households through the students of different schools revealed that 289 (16.0%) had less than 15 ppm iodine. Two hundred forty-one powder salt samples without two children logo (14.3% among total powder salt samples) had iodine below 15 ppm. It includes 25.8% of total salt samples from Parsa district of Terai ecological region. Among total, the largest proportion of the population accounting for almost 93.0% used powder salt. In total 1803 salt samples, mean and median iodine concentration were 31.8 ppm (95.0% CI=31.0-32.6) and 29.5 ppm respectively. The mean and median iodine concentration of phoda (dhike) salt were 22.1 ppm (95.0% CI= 19.2-25.1) and 18.9 ppm; powder salt were 32.6 ppm (95.0% CI= 31.7- 33.4) and 30.6 ppm respectively. In the community level, people are still using the non-iodized salt. To eliminate the IDD more efforts are required at program implementation and monitoring level.

Influence of physico-chemical factors on leaching of chemical additives from aluminium foils used for packaging of food materials.

In recent years, the use of aluminium foils to wrap foodstuff and commodities has been increased to a great extent. Aluminium was found to leach out from the foil in different simulants particularly in distilled water, acidic and alkaline medium at 60 +/- 2 degrees C for 2 hours and 40 +/- 2 degrees C for 24 hours. The migration was found to be above the permissible limit as laid down by WHO guidelines, that is of 0.2 mg/L of water. The protocol used for this study was based on the recommendation of Bureau of Indian Standard regarding the migration of chemical additives from packaging materials used to pack food items. Migration of the aluminium metal was found significantly higher in acidic and aqueous medium in comparison to alcoholic and saline medium. Higher temperature conditions also enhanced the rate of migration of aluminium in acidic and aqueous medium. Leaching of aluminium metal occurred in double distilled water, acetic acid 3%, normal saline and sodium carbonate, except ethanol 8%, in which aluminium migration was below the detection limit of the instrument where three brands of the aluminium foil samples studied.

Textile anionic dyes recovery using tri-n-butyl phosphate as carrier through supported liquid membrane.

The recovery of anionic dyes Acid Red10 B (CI Acid Violet 54) and Acid Pink BE (CI Acid Red 183) in flat type supported liquid membrane (SLM) using tri-n-butyl phosphate as carrier was studied. The parameters studied were the effect of feed phase pH, stripping reagent concentration, string speed and initial dye concentration on permeability of dyes. The influence of salt concentration such as sodium chloride and sodium sulphate on the dye recovery was examined. The reusability of membrane and kinetics of transport were also studied. The optimum conditions of transport are feed phase pH 1 +/- 0.1, 0.1 M sodium hydroxide as stripping phase, stirring speed at 500 rpm. The maximum recovery under optimum conditions was observed as 94.2 % for Acid Red10 B and 85.7 % for Acid Pink BE. The maximum permeability was 11.0 x 10(-6) m/s for Acid Red10 B and 7.7 x 10(-6) m/s for Acid Pink BE.

NaCl induced changes in photosystem stoichiometry and photosynthetic activity of the cyanobacterium Microcystis aeruginosa Kütz.

Exposure to 0.4 M NaCl resulted in higher PS I/PS II stoichiometry and increase in the rate of photosynthesis in planktonic cyanobacterium M. aeruginosa. Altered ratios of PS I/PS II as well as photosynthesis and respiration were stabilized within 72 hr of exposure to salt, leading to adaptation of the organism to the changed conditions.

Iodine nutritional status & prevalence of goitre in Sundarban delta of South 24-Parganas, West Bengal.

BACKGROUND & OBJECTIVE: In post salt iodization phase endemic goitre and associated iodine deficiency disorders (IDD) were found prevalent in a randomly selected rural area of Sundarban delta and its adjoining areas of West Bengal. The present investigation was thus undertaken to study the total goitre rate, urinary iodine and thiocyanate excretion pattern of the school going children, iodine content in edible salt and drinking water in the Sundarban delta of South 24-Parganas in West Bengal. METHODS: A total of 4656 school children (6-12 yr) were clinically examined for goitre from 13 different areas in the delta region. Urinary iodine and thiocyanate levels were measured in 520 (40 from each area) samples collected randomly to evaluate the iodine nutritional status and consumption pattern of dietary goitrogen. Simultaneously iodine content was determined in 104 (8 from each area) drinking water samples and 455 (35 from each area) edible salt samples collected from the areas. RESULTS: Children of all the areas were affected by endemic goitre. The prevalence rates were in the ranges from 25-61 per cent; overall goitre prevalence was 38.2 per cent (grade 1--34.0%; grade 2--4.2%). Median urinary iodine level in the studied areas was 225 microg/l (range 115-525 microg/l) indicating no biochemical iodine deficiency in the region. Mean urinary thiocyanate levels were in the range from 0.326-1.004 mg/dl. Iodine content in drinking water samples were in the ranges from 22-119 microg/l, and 55.6 per cent edible salt samples had iodine level above the recommended 15 ppm at the consumption point. INTERPRETATION & CONCLUSION: The severity of endemic goitre was high in the studied population though the iodine nutritional status was found satisfactory in the region indicating no biochemical iodine deficiency. The people of the region consumed iodine through iodized salt but about 44 per cent of the salt samples at household level contained inadequate iodine, however their iodine intake was compensated through iodine in water and food. They also consumed dietary goitrogen. Environmental factors other than iodine deficiency may have possible role for the persistence of endemic goitre in the region. More investigations are thus necessary to arrive at certain definite cause of high goitre rates in this population.