Post-Partum Depression Lactating Rat Model for Evaluating Ketamine's Safety as a Pharmacotherapeutic Treatment: Roles in Cardiac and Urinary Function.

Depression is one of the world's most common and mentally disabling illnesses. Post-partum depression is a subtype of depression that affects one in seven women worldwide. Successful pharmacological treatment must consider the consequences for both, since the mother-child bond is fundamental for the well-being of both mother and infant as well as the general development of the newborn. Changes in maternal physiology and/or behavior can significantly influence the development of breastfed infants. Ketamine has been extensively studied for use as an antidepressant due to its mixed mechanisms of action. Safety and efficacy studies in the cardiovascular and urinary systems of a lactating postpartum depression animal model are essential for contributing toward ketamine's clinical use in the respective patient population. Thus, this project aimed to study the implications of postpartum maternal exposure to ketamine during lactation on the cardiovascular system of female rats submitted to the depression induction model by maternal separation. This model promotes depressive effects through stress caused by the interruption of mother-infant bond early in the offspring's life. To achieve depression, each dam was separated from her offspring for 3 h per day, from post-natal day 2 (PND2) to PND12. Experimental groups received daily treatment with either 5, 10, or 20 mg/kg of ketamine intraperitoneally during the lactation period, from PND2 to PND21. Behavioral tests consisted of the maternal and aggressive maternal behavior tests, the olfactory preference test, and the forced swim test. A technique for the detection of catecholamines and indoleamines in the heart muscle was developed for the experimental model groups. The histopathological evaluation was performed on these animals' cardiac muscles and urinary bladders. Our findings suggest that ketamine is safe for use in postpartum depression and does not induce cardiovascular and/or urinary systems toxicity.

Development, Optimization, and Validation of Forensic Analytical Method for Quantification of Anticholinesterase Pesticides in Biological Matrices from Suspected Cases of Animal Poisoning.

Anticholinesterase pesticides are a main cause of the intentional or accidental poisoning of animals. Anticholinesterases include several substances that cause the overstimulation of both central and peripheral acetylcholine-dependent neurotransmission. Forensic analyses of poisoning cases require high levels of expertise, are costly, and often do not provide reliable quantitative information for unambiguous conclusions. The purpose of the present study was to develop and validate a method of high-performance liquid chromatography with diode array detector (HPLC−DAD) for the identification and quantitation of n-methyl carbamates, organophosphates and respective metabolites from biological samples of animals that were suspected of poisoning. HPLC−DAD is reliable, fast, simplistic and cost-effective. The method was validated for biological samples obtained from stomach contents, liver, vitreous humor and blood from four different animal species. The validation of the method was achieved using the following analytical parameters: linearity, precision, accuracy, selectivity, recovery, and matrix effect. The method showed linearity at the range of 25−500 µg/mL, and the correlation coefficient (r2) values were >0.99 for all matrices. Precision and accuracy were determined by the (a) coefficient of variation (CV), (b) relative standard deviation low-quality control (LQC), (c) medium-quality control (QCM), and (d) high-quality control (QCA). The indicated parameters were all less than 15%. The recovery of analytes ranged from 31 to 71%. The analysis of results showed no significant interfering peaks due to common xenobiotics or matrix effects. The abovementioned method was used to positively identify pesticide analytes in 44 of the 51 animal samples that were suspected of poisoning, demonstrating its usefulness as a forensic tool.

Adverse events related to oral hormonal contraceptive use in undergraduate pharmacy students: a cross-sectional study

Abstract We aimed to measure the prevalence of adverse events related to oral hormonal contraceptive (OHC) use and their associated factors in undergraduate pharmacy students. A cross-sectional study was conducted by using an online questionnaire for female students of the Faculty of Pharmaceutical Sciences of the University of São Paulo from July to August 2020. A descriptive analysis of the data was carried out, which was followed by determining the prevalence ratios to identify possible factors associated with adverse events resulting from OHC. A total of 269 valid responses were obtained, among which 50.2% (n = 135) of the students reported using OHC as a contraceptive method and 21.2% (n = 57) affirmed that they had at least one adverse event related to OHC use, which corresponds to 42.2% of those who had used OHC. The most common adverse event was headache (70.2%), and a period of less than one month was the most cited (49.1%). Only migraine comorbidity was associated with the occurrence of adverse events related to OHC. These findings reinforce the high incidence of adverse events among OHC users and the low rate of discontinuation due to these events. There is a need to provide more information on contraceptive methods to users, including its risks and contraindications.

Fasciola hepatica prevalence in cattle from the Abancay, Curahuasi and Tamburco districts, Abancay province-Apurímac, Peru during the 2018 rainy season

This study aims to determine the prevalence of Fasciola hepatica in cattle from the Abancay, Curahuasi, and Tamburco districts in the Abancay province, Apurímac, Peru, during the 2018 rainy season, and the association between prevalence and age, breed, and district of origin. In total, 295 stool samples were collected, namely 34 from Tamburco, 193 from Curahuasi and 68 from Abancay. For coproparasitological evaluation, the four-sieve sedimentation technique described by Girão and Ueno was used. The total prevalence of F. hepatica in the cattle sampled in this study was 50.8% (150/295), and the prevalence by district was 42.6% (29/68) in Abancay, 53.8% (104/193) in Curahuasi, and 50% (17/34) in Tamburco. No significant association was found with the variable district of origin (p<0.05). However, using a bivariate logistic regression analysis, a significant association was found between F. hepatica prevalence and the breed variable (p=0.008). A similar significant association with the breed variable (p=0.007) was also found using a multiple logistic regression analysis. The high prevalence of F. hepatica identified in this study is consistent with previous reports made in the Apurímac Region, an area considered hyperendemic for the parasite, thus highlighting the need for effective health programs to control disease distribution, which may have an economic and, because of its zoonotic character, public health impact.

The effects of pharmacist interventions on health outcomes in patients with advanced prostate cancer in Brazil

Abstract This study examined the effects of pharmacist interventions for patients with advanced prostate cancer. A pre-post study was conducted between October 2014 and August 2017 in a community pharmacy in Brazil for outpatients with advanced prostate cancer, aged ≥ 18 years, using cyproterone acetate and/or goserelin. The patients had face-to-face meetings with a pharmacist who dispensed antiandrogenic drugs and performed interventions aimed at solving and/or preventing drug-therapy problems. Primary outcomes regarding prostate-specific antigen (PSA) and testosterone levels were compared at 0, 6, and 12 months, whereas secondary outcomes-medication adherence and quality of life-were compared at baseline and at the 12-month follow-up. Medication adherence was assessed using the Morisky-Green test, and quality of life was measured by the Medical Outcomes Study 36-item Short Form (SF-36) and the Functional Assessment of Cancer Therapy-Prostate (FACT-P). The analysis included 20 patients; 311 drug-therapy problems were identified and most of them were related to adverse reactions (78.5%). The most common adverse reactions were reduced libido, erectile dysfunction, hyperglycemia, fatigue, and gynecomastia. Testosterone levels significantly decreased at 6 months, and PSA levels at 6 and 12 months. No significant changes in adherence were noted at the end of the study. A significant increase in the "pain" domain and an improvement trend in the "physical aspects" and "vitality" domains were observed based on the SF-36 instrument. The findings show that pharmacist interventions were able to improve PSA and testosterone levels, and some domains of quality of life of patients.

Judicialização da saúde: uma análise do fenômeno e suas consequências para a sociedade brasileira / Judicialization of health: An analysis of the phenomenon and its consequences to Brazilian society

Embora o Sistema Único de Saúde tenha avançado desde sua criação, ainda há falhas no fornecimento de medicamentos e serviços. Com isso, cidadãos têm utilizado o sistema judiciário para aquisição de bens de saúde, prática conhecida como judicialização da saúde, que teve um crescimento abrupto nos últimos anos. Diante disso, o trabalho tem como objetivo analisar as ações judiciais que requerem bens de saúde ao SUS para proporcionar melhor compreensão dos efeitos da naturalização da judicialização da saúde. Foram realizadas uma revisão bibliográfica e análise de 100 processos judiciais do portal eletrônico do Tribunal de Justiça do Estado de São Paulo. Os resultados indicaram que, em 2010, o gasto do governo federal com a judicialização da saúde foi de R$ 120 milhões. Já em 2016, esse gasto foi de cerca de R$ 1,6 bilhão, com 1.346.931 processos movidos no Brasil. A análise descritiva realizada demonstrou que, no mesmo ano, 22,1% das ações judiciais selecionadas solicitaram medicamentos padronizados pelo SUS e, em relação às demais solicitações, 82,8% possuíam alternativa terapêutica disponível na rede pública. Os valores apresentados demonstram a desestabilização do planejamento orçamentário para a área da saúde gerada pela judicialização. É necessário buscar estratégias de garantia do direito à saúde e ampliar o conhecimento das listas disponibilizadas pela rede pública para médicos e juízes. Dessa forma, a judicialização da saúde permanecerá viável para a garantia dos direitos em casos não contemplados pelo sistema de saúde, sem prejuízo ao planejamento orçamentário e acesso universal ao Sistema Único de Saúde.

Although the Brazilian National Health System advanced since its creation, there are still failures in supplying medicines and services. For this reason, citizens have been using the judicial system to acquire health assets, what is known as judicialization of health. In the last years, this practice had an abrupt increase. This work has the purpose of analyzing the lawsuits that request provision of health assets through SUS to provide greater understanding of the effects of the naturalization of judicialization of health. To do this, a bibliographic review was conducted, besides the analysis of 100 lawsuits on the Tribunal de Justiça do Estado de São Paulo's website. The results indicated that in 2010, the government spending on judicialization of health was R$ 120 million, whereas in 2016 it was around R$ 1.6 billion, reaching 1,346,931.00 actions moved in Brazil. The descriptive analysis demonstrated that, in the same year, nearly 22.1% of the selected lawsuits requested medicines, which are standardized by SUS. In relation to the other requests, 82.8% disposed of therapeutic alternative available in public system. The numbers demonstrate the destabilization of budget planning to the health sector caused by judicialization. It is necessary to seek strategies to ensure the right to health and to enlarge the knowledge of standardized lists provided in public system to doctors and judges. The judicialization will therefore remain available to guarantee rights in cases not covered by the health system, without the excesso of lawsuits damaging the budget planning and universal access to the system.

Determinação de paraquate em batatas

O Paraquate (1,1'-dimetil-4,4'-bipiridina-dicloreto) é herbicida amplamente utilizado em vários países para diferentes culturas. O objetivo é determinar a concentração de Paraquate em batatas comercializadas em diferentes estabelecimentos da zona leste de São Paulo. Foram coletadas 12 (doze) amostras de batatas adquiridas no comércio varejista (sacolões, ou seja, do de frutas, verduras e legumes; supermercados e feiras livres) da zona leste do município de São Paulo. A quantificação do Paraquate foi baseada na reação de complexação com o ditionito de sódio, gerando composto de cor azulada, cuja absorvância foi lida em espectrofotômetro em comprimento de onda de 600nm. Foi construída a curva padrão e a determinada a equação da reta (y = 1,6448x e R2= 0,9945). O limite de tolerância do herbicida em alimentos é de 0,2 partes por milhão ou 0,2 mg/kg, enquanto que a ingestão diária aceitável (IDA) é de 0,004 mg/kg de peso corpóreo. Assim, pode-se observar que os valores encontrados em três amostras estão acima do limite máximo permitido, enquanto quatro apresentaram concentrações muito próximas ao limite. Os resultados permitem inferir que existe a necessidade de intensificação na fiscalização nos locais de comercialização de alimentos produzidos com a utilização de agrotóxicos.(AU)

Paraquat (1,1'-dimethyl-4,4'- bipyridine-dichloríde) is herbicide widely used in several countries in different plantations. The objective is to determine the concentration of Paraquat in potatoes, marketed in different establishments in the eastern zone of São Paulo. Twelve (12) samples of potatoes purchased from the retail trade ("sacolões", ie fruit, vegetable and vegetable markets, supermarkets and free markets) were collected from the eastern part of the city of São Paulo. The quantification of Paraquat was based on the reaction of complexation with the sodium dithionite, generating compound of blue color, whose absorbance was read in a spectrophotometer at wavelength of 600 nm. The standard curve was constructed and the equation of the tine was determined (y=1,6448x e R2=0,9945). The tolerance limit of the herbicide infoods is 0.2 parts per million or 0.2 mg/kg, while the acceptable daily intake (ADI) is 0.004 mg/kg body weight. Thus, it can be observed that the values found in three samples are above the maximum allowed limit, while four of them presented concentrations very close to the limito The results allow inferring that there is a need for intensification in the inspection in the commercial places of food produced with the use of pesticides.(AU)

Determinação de paraquate em batatas / Determination of paraquat in potatoes

O Paraquate (1,1'-dimetil-4,4'-bipiridina- dicloreto) é herbicida amplamente utilizado em vários países para diferentes culturas. O objetivo é determinar a concentração de Paraquate em batatas comercializadas em diferentes estabelecimentos da zona leste de São Paulo. Foram coletadas 12 (doze) amostras de batatas adquiridas no comércio varejista (sacolões, ou seja, do de frutas, verduras e legumes; supermercados e feiras livres) da zona leste do município de São Paulo. A quantificação do Paraquate foi baseada na reação de complexação com o ditionito de sódio, gerando composto de cor azulada, cuja absorvância foi lida em espectrofotômetro em comprimento de onda de 600nm. Foi construída a curva padrão e a determinada a equação da reta (y = 1,6448x e R2= 0,9945). O limite de tolerância do herbicida em alimentos é de 0,2 partes por milhão ou 0,2 mg/kg, enquanto que a ingestão diária aceitável (IDA) é de 0,004 mg/kg de peso corpóreo. Assim, pode-se observar que os valores encontrados em três amostras estão acima do limite máximo permitido, enquanto quatro apresentaram concentrações muito próximas ao limite. Os resultados permitem inferir que existe a necessidade de intensificação na fiscalização nos locais de comercialização de alimentos produzidos com a utilização de agrotóxicos.(AU)

Paraquat (1,1'-dimethyl-4,4'- bipyridine-dichloride) is herbicide widely used in several countries in different plantations. The objective is to determine the concentration of Paraquat in potatoes, marketed in different establishments in the eastern zone of São Paulo. Twelve (12) samples of potatoes purchased from the retail trade ("sacolões", ie fruit, vegetable and vegetable markets, supermarkets and free markets) were collected from the eastern part of the city of São Paulo. The quantification of Paraquat was based on the reaction of complexation with the sodium dithionite, generating compound of blue color, whose absorbance was read in a spectrophotometer at wavelength of 600 nm. The standard curve was constructed and the equation of the line was determined (y = 1,6448x e R2 = 0,9945). The tolerance limit of the herbicide in foods is 0.2 parts per million or 0.2 mg/kg, while the acceptable daily intake (ADI) is 0.004 mg/kg body weight. Thus, it can be observed that the values found in three samples are above the maximum allowed limit, while four of them presented concentrations very close to the limit. The results allow inferring that there is a need for intensification in the inspection in the commercial places of food produced with the use of pesticides.

Graph-based Clustering of miRNA Sequences.

AIMS: The many miRNAs discovered so far have been divided into biologically representative families, aiming at organizing and systematizing their study so to promote, mainly, a better understanding of their functionalities. Clustering miRNA sequences can corroborate the family-based organizations as well as helping to explore sequences belonging to the same cluster as potentially having similar biological functions. OBSERVATIONS: Considering that members of the same miRNA family tend to biologically function in similar ways, a well-structured family can help detecting miRNA functions which have not been associated yet with any existing family. METHODS: The work described in this paper empirically investigates the suitability of organizing miRNAs as families, using a clustering algorithm based on a particular type of graph i.e., minimal spanning tree (MST), for clustering miRNA sequences. Seven miRNA families stored in the online miRBase database have been used as input to the MST-based clustering algorithm and clustering results have been compared to assess the suitability of identirying them. RESULTS: The motivations for the experiments were to identify refinements in miRNA family organizations that could be pursued and, also, investigate how the chosen graph-based clustering algorithm would perform in miRNA related domains. CONCLUSION: Interesting and useful results, particularly related to detecting information based on the visualization of the final induced graphs, and their induced connected components (clusters), are presented and discussed. Particularly, experiments results suggested the possibility of refining some miRNA families by grouping some of their miRNAs as sub-families.

Quantitative Analysis of Rat Dorsal Root Ganglion Neurons Cultured on Microelectrode Arrays Based on Fluorescence Microscopy Image Processing.

Microelectrode Arrays (MEA) are devices for long term electrophysiological recording of extracellular spontaneous or evocated activities on in vitro neuron culture. This work proposes and develops a framework for quantitative and morphological analysis of neuron cultures on MEAs, by processing their corresponding images, acquired by fluorescence microscopy. The neurons are segmented from the fluorescence channel images using a combination of segmentation by thresholding, watershed transform, and object classification. The positioning of microelectrodes is obtained from the transmitted light channel images using the circular Hough transform. The proposed method was applied to images of dissociated culture of rat dorsal root ganglion (DRG) neuronal cells. The morphological and topological quantitative analysis carried out produced information regarding the state of culture, such as population count, neuron-to-neuron and neuron-to-microelectrode distances, soma morphologies, neuron sizes, neuron and microelectrode spatial distributions. Most of the analysis of microscopy images taken from neuronal cultures on MEA only consider simple qualitative analysis. Also, the proposed framework aims to standardize the image processing and to compute quantitative useful measures for integrated image-signal studies and further computational simulations. As results show, the implemented microelectrode identification method is robust and so are the implemented neuron segmentation and classification one (with a correct segmentation rate up to 84%). The quantitative information retrieved by the method is highly relevant to assist the integrated signal-image study of recorded electrophysiological signals as well as the physical aspects of the neuron culture on MEA. Although the experiments deal with DRG cell images, cortical and hippocampal cell images could also be processed with small adjustments in the image processing parameter estimation.

Evaluation of the inflammatory response of the subcutaneous conjunctive of mice against some endodontic irrigations solutions

Introduction: Sodium hypochlorite has been used as an endodontic irrigant since 1936, when Walker used it as Sodium Chlorine. Since then it has became the most well acceptable endodontic irrigant. During the last few years many studies have reported the importance of pH control. Objective: This study evaluates the inflammatory response of some endodontic irrigations solutions in the subcutaneous connective tissue of mice. Material and methods: Thirty-six mice were obtained from the Biomedical Sciences Institute at the University of São Paulo. Their backs were divided into four quadrants and each quadrant was injured with an 8 mm punch. Three of these wounds were submitted to differents solutions, while the fourth was used as a control. This experiment was done in triplicate. After the irrigation of the wounds, the mice were sacrificed at 3, 7 and 14 days. The samples were fixed on 10% formalin and histologically analyzed after hematoxylin and eosin staining. Results: At 14 days all wounds were covered with epithelium with a mild inflammatory infiltrate in the subjacent connective tissue, except for the group that employed 5% sodium hypochlorite at pH 11. Conclusion: The greatest the pH and concentration of sodium hypochlorite solutions, the most toxic they are.

Influence of irrigant viscosity on torsional fracture resistance ofrotary nickel-titanium instruments / Influência da viscosidade da substância química auxiliar na resistência à fratura por torção de instrumentos rotatórios de níquel-titânio

Objective: The main goal of the study was to evaluate the influence of the torsion caused by chemical substances with different viscosity levels on the fracture strength of nickel-titanium rotary dental instruments.Methods: Tapered Instruments K3 #25 and 0.04 were used to prepare simulated canals with: Endo PTC, modified Endo PTC and distilled water. After 12 consecutive preparations using each instrument, they were submitted to the fracture test by torsion, which determined the resistance, in degrees, of each instrument in each experimental situation. Data were collected, analyzed and submitted to statistical analysis using the Kruskal-Wallis test. Results: The statistical data analysis showed that there were no statistically significant differences as regards resistance to torsion of rotary instruments, with changes in level of viscosity of the substance that helps instrumentation. Conclusion: Viscosity level of the chemical substance used during root canal preparation does not interfere in resistance to torsion of rotary instruments up to 12 consecutive times of use

Objetivo: Avaliar a influência de substâncias químicas, utilizadas durante o preparo do canal, com diferentes viscosidades na resistência à fratura por torção de instrumentos rotatórios de níquel-titânio. Métodos: Instrumentos K3 #25 e conicidade 0.04 foram utilizados no preparo de canais simulados com: Endo PTC, Endo PTC modificado e água destilada. Após 12 preparos consecutivos com cada instrumento estes foram submetidos ao teste de fratura por torção em um troptômetro, que determinou a resistência, em graus, de cada instrumento em cada situação experimental. Os dados foram tabulados e submetidos à análise estatística pelo teste de Kruskal-Wallis. Resultados: A análise estatística dos dados apresentados revelou não haver diferenças estatisticamente significantes no que respeita a resistência à torção de instrumentos rotatórios ao variar-se a viscosidade da substância auxiliar da instrumentação. Conclusão: A viscosidade da substância química utilizada durante o preparo do canal radicular não interfere na resistência à fratura de instrumentos rotatórios até 12 utilizações.

Cytotoxicity evaluation of Curcuma zedoaria (Christm.) Roscoe fluid extract used in oral hygiene products.

OBJECTIVE: This in vitro study evaluated the cytotoxic effects of the Curcuma zedoaria (Christm.) Roscoe (popular name: zedoary) fluid extract, as used in preparations for oral hygiene, mostly for anti-septic purposes. MATERIALS AND METHODS: The cell viability and cell growth were assessed by Trypan blue dye exclusion assay using the LMF cell line derived from oral mucosa. Cell viability (short-term assay) was measured 0, 6, 12 and 24 h after contact with the fluid extract. Cell growth (long-term assay) was analyzed in 1, 3, 5 and 7 days. The experimental groups were those testing the fluid extract obtained from the zedoary rhizome and the extractor liquid (ethanol 70° GL) in the concentrations of 0.01-0.0001% v/v. Fresh DMEM were used in the control cultures. RESULTS: Short-term assay-all studied cultures maintained stable cell viability; Long-term assay-there was progressive cell growth in all studied cultures. CONCLUSION: According to the results, the zedoary fluid extract presents low cytotoxicity and probably can be used in the oral hygiene products.

Variability in the proportion of components of iodoform-based Guedes-Pinto paste mixed by dental students and pediatric dentists.

OBJECTIVE: Guedes-Pinto paste (GPP) is an iodoform paste used in most dental schools in Brazil. The paste is a composite of medicines (Rifocort , camphorated paramonochlorophenol [PMCC], and iodoform) used for endodontic treatment of primary teeth. The aim of this study was to evaluate the proportion variability of GPP components when mixed by undergraduate dentistry students and pediatric dentists. MATERIALS AND METHODS: The study was divided into 4 groups: G1 (15 undergraduate students), G2 (15 specialists in Pediatric Dentistry), G3 (15 professors with clinical activity), and G4 (7 professors-researchers). All volunteers prepared GPP according to the original specifications: the same visual proportion for each component. The components were weighed using an analytical balance and the percentage was calculated. RESULT: After normality (Kolmogorov-Smirnov) and homogeneity tests (Levene test), the data were submitted to analysis of variance and intraclass correlation coefficient tests (P<0.05). The percentage means of each respective group were as follows: Rifocort 20.2%, 20.8%, 26.7%, 27.3%; camphorated PMCC 9.2%, 8.1%, 6.7%, 5.1%; and the iodoform 70.6%, 71.1%, 64.7%, 67.6%. There were no significant differences between groups for the component percentages. There was a high intraclass correlation coefficient (G1 0.945; G2 0.951; G3 0.921; and G4 0.870). CONCLUSION: The proportion of GPP was similar in all the groups, allowing us to conclude that ideal GPP proportion, based on the entire group mean, was 23.8% of Rifocort® ; 7.0% of camphorated PMCC; and 69.2% of iodoform.

Análise das soluções de hipoclorito de sódioutilizadas por endodontistas / Evaluation of sodium hypochlorite solutionsused by endodontists

Introdução: O sucesso da terapia endodôntica está condicionado adiversos fatores, entre os quais o uso de substâncias químicas deboa qualidade. Objetivo: Neste trabalho investigaram-se algumascaracterísticas das soluções de hipoclorito de sódio utilizadas emclínicas de atendimento, tais como concentração, pH e armazenagem.Material e métodos: Para isso, distribuiu-se formulário com perguntasrelativas à solução empregada a 100 endodontistas, além de pedir-lhes100 ml do produto. As amostras foram levadas ao laboratório paraanálise por titulometria da concentração de cloro residual livre, bemcomo do pH das soluções, com o auxílio de um peagômetro. Resultados:Apenas 1% dos profissionais conhece o valor do pH das soluções. Dasamostras recolhidas, 36% apresentaram pH 9, 22% pH 10, 16% compH 13, 14% pH 12, 11% pH 11 e 1% pH 8. Quanto aos profissionais,37% mantinham seus frascos sob refrigeração e 67% em temperatura ambiente. Conclusão: Os endodontistas usam soluções de hipocloritode sódio diferentes daquelas que desejam por desconhecerem ascondições necessárias para a manutenção da estabilidade química.

Introduction: The success of endodontic therapy is conditioned byseveral variables, being the use of good quality chemical agents one ofthem. Objective: In this study, some characteristics of commonly usedsodium hypochlorite irrigants were investigated, such as: concentration,pH, and storage conditions. Material and methods: For this purpose, aquestionnaire comprising questions regarding the employed irrigant wassent to 100 endodontists. Besides that, a 100mL sample of the sodiumhypochlorite irrigant used by them was collected. Free residual chlorinedetermination was laboratorially carried out through titration method.Additionally, pH was measured, through peagameter reading. Results:Only 1% of the professionals did know the pH value of the solutionsused by them. Concerning to pH value, 36% of the solutions presentedpH 9; 22%, pH 10; 16%, pH 13; 14%, pH 12; 11%, pH 11; and 1%, pH8. 37% of the endodontists kept the solution flasks under refrigeration,and 67% kept them at environmental temperature. Conclusion: It can beconcluded that the endodontists are using altered hypochlorite solutionsbecause they fail to observe the necessary conditions for maintainingthe solution?s chemical stability.

José Goldemberg: entrevista / José Goldemberg: entrevista / José Goldemberg: interview

Doutor em Ciências Físicas pela Universidade de São Paulo da qual foi Reitor de 1986 a 1990, Presidente da Companhia Energética de São Paulo (CESP); Presidente da Sociedade Brasileira para o Progresso da Ciência; Secretário de Ciência e Tecnologia; Secretário do Meio Ambiente da Presidência da República; Ministro da Educação do Governo Federal e Secretário do Meio Ambiente do Estado de São Paulo. Foi Diretor do Instituto de Física da Universidade de São Paulo; professor/pesquisador: da Universidade de Paris (França); Princeton (Estados Unidos); High Energy Physics Laboratory da Universidade de Stanford, EUA; Universidade de Toronto, Canadá e ocupante da Cátedra Joaquim Nabuco da Universidade de Stanford (Estados Unidos). É Membro da Academia Brasileira de Ciências e Academia de Ciências do Terceiro Mundo; Co-Presidente do Global Energy Assessment, sediado em Viena. É autor de inúmeros trabalhos técnicos e vários livros sobre Física Nuclear, Meio Ambiente e Energia em geral. Foi selecionado pela Time Magazine como um dos 13 “Heroes of the Environment in the category of Leaders and Visionaries 2007”. Recebeu o prêmio “Blue Planet Prize 2008” concedido pela Asahi Glass Foundation(AU)

José Goldemberg: entrevista / José Goldemberg: entrevista / José Goldemberg: interview

Doutor em Ciências Físicas pela Universidade de São Paulo da qual foi Reitor de 1986 a 1990, Presidente da Companhia Energética de São Paulo (CESP); Presidente da Sociedade Brasileira para o Progresso da Ciência; Secretário de Ciência e Tecnologia; Secretário do Meio Ambiente da Presidência da República; Ministro da Educação do Governo Federal e Secretário do Meio Ambiente do Estado de São Paulo. Foi Diretor do Instituto de Física da Universidade de São Paulo; professor/pesquisador: da Universidade de Paris (França); Princeton (Estados Unidos); High Energy Physics Laboratory da Universidade de Stanford, EUA; Universidade de Toronto, Canadá e ocupante da Cátedra Joaquim Nabuco da Universidade de Stanford (Estados Unidos). É Membro da Academia Brasileira de Ciências e Academia de Ciências do Terceiro Mundo; Co-Presidente do Global Energy Assessment, sediado em Viena. É autor de inúmeros trabalhos técnicos e vários livros sobre Física Nuclear, Meio Ambiente e Energia em geral. Foi selecionado pela Time Magazine como um dos 13 “Heroes of the Environment in the category of Leaders and Visionaries 2007”. Recebeu o prêmio Blue Planet Prize 2008 concedido pela Asahi Glass Foundation.

Shelf-life of a 2.5% sodium hypochlorite solution as determined by Arrhenius equation.

Accelerated stability tests are indicated to assess, within a short time, the degree of chemical degradation that may affect an active substance, either alone or in a formula, under normal storage conditions. This method is based on increased stress conditions to accelerate the rate of chemical degradation. Based on the equation of the straight line obtained as a function of the reaction order (at 50 and 70 degrees C) and using Arrhenius equation, the speed of the reaction was calculated for the temperature of 20 degrees C (normal storage conditions). This model of accelerated stability test makes it possible to predict the chemical stability of any active substance at any given moment, as long as the method to quantify the chemical substance is available. As an example of the applicability of Arrhenius equation in accelerated stability tests, a 2.5% sodium hypochlorite solution was analyzed due to its chemical instability. Iodometric titration was used to quantify free residual chlorine in the solutions. Based on data obtained keeping this solution at 50 and 70 degrees C, using Arrhenius equation and considering 2.0% of free residual chlorine as the minimum acceptable threshold, the shelf-life was equal to 166 days at 20 degrees C. This model, however, makes it possible to calculate shelf-life at any other given temperature.

Shelf-life of a 2.5 percent sodium hypochlorite solution as determined by arrhenius equation

Accelerated stability tests are indicated to assess, within a short time, the degree of chemical degradation that may affect an active substance, either alone or in a formula, under normal storage conditions. This method is based on increased stress conditions to accelerate the rate of chemical degradation. Based on the equation of the straight line obtained as a function of the reaction order (at 50 and 70 ºC) and using Arrhenius equation, the speed of the reaction was calculated for the temperature of 20 ºC (normal storage conditions). This model of accelerated stability test makes it possible to predict the chemical stability of any active substance at any given moment, as long as the method to quantify the chemical substance is available. As an example of the applicability of Arrhenius equation in accelerated stability tests, a 2.5 percent sodium hypochlorite solution was analyzed due to its chemical instability. Iodometric titration was used to quantify free residual chlorine in the solutions. Based on data obtained keeping this solution at 50 and 70 ºC, using Arrhenius equation and considering 2.0 percent of free residual chlorine as the minimum acceptable threshold, the shelf-life was equal to 166 days at 20 ºC. This model, however, makes it possible to calculate shelf-life at any other given temperature.

Testes acelerados de estabilidade são indicados para avaliar, em um curto período de tempo, o grau de degradação química que poderá afetar uma substância química, isoladamente ou quando inserida em uma fórmula, sob condições normais de armazenamento. Este método está fundamentado na intensificação das condições de estresse para acelerar a velocidade de degradação química. Baseando-se na equação da reta obtida e na ordem de reação determinada (a 50 e 70 ºC) e usando a equação de Arrhenius, a velocidade de reação foi calculada para a condição de temperatura de 20ºC (condições normais de armazenamento). Este modelo de teste acelerado de estabilidade torna possível a predição da estabilidade química de qualquer substância, em qualquer tempo, desde que o método de quantificação da substância química esteja disponível. Como exemplo da aplicabilidade da equação de Arrhenius em teste acelerado de estabilidade, uma solução de hipoclorito de sódio a 2,5 por cento foi analisada por ser quimicamente instável. A quantificação do cloro residual livre foi determinada através de titulação iodométrica. A partir dos dados obtidos decorrentes das amostras submetidas às temperaturas de 50 e 70 ºC e com o emprego da equação de Arrhenius, o tempo de prateleira obtido foi de 166 dias em temperatura de 20 ºC, considerando como limite inferior a concentração de 20 mg/mL de cloro residual livre. Este modelo, entretanto, possibilita o cálculo de tempo de prateleira em qualquer outra temperatura de interesse.