Clinical implementation of comprehending dentin on a microscopic level

SUMMARY: The aim of the present in vitro study is to visualize dentin to get an in-depth knowledge of the nature of dentin that could provide useful information regarding conditioning dentinal substrate when treating dentinal lesions. Forty-nine extracted human third molars were obtained and prepared to produce artificial dentinal lesions through demineralizing with acetic acid for 7 and 14 days, or lactic acid for 7 days. The teeth were divided into groups and treated with either NaOCl, pepsin, trypsin, or phosphoric acid. To obtain information on the morphology of the treated dentinal surfaces, all samples were visualized under high resolution field emission scanning electron microscope. With high magnification reaching x50000 dentin was clearly visualized together with its constitutes. The effect of various demineralization approaches and various treatment protocols were demonstrated clearly. The relationship between the conditioning procedure steps and the subsequent bond strength was discussed. To our best knowledge, there is no previous clear highly magnified scanning electron microscope images for dentin, and dentinal components and constitutes with and without various treatments. The current in vitro study suggests the complexity nature of dentin as a substrate that should be treated carefully especially with technique sensitive procedures such as adhesive restorations.

El objetivo del presente estudio in vitro fue visualizar la dentina para obtener un conocimiento completo de la naturaleza de ella lo que podría proporcionar información útil sobre el acondicionamiento del sustrato dentinario en el tratamiento de lesiones dentinarias. Se obtuvieron 49 terceros molares humanos extraídos y se prepararon para producir lesiones dentinales artificiales mediante desmineralización con ácido acético por 7 y 14 días, o ácido láctico por 7 días. Los dientes se dividieron en grupos y se trataron con NaOCl, pepsina, tripsina o ácido fosfórico. Para obtener información sobre la morfología de las superficies dentinarias tratadas, todas las muestras se visualizaron bajo un microscopio electrónico de barrido de emisión de campo de alta resolución. Con un gran aumento que alcanzó x50000, la dentina se visualizó claramente junto con sus componentes. Se demostró el efecto de varios enfoques de desmineralización y varios protocolos de tratamiento. Se discutió la relación entre los pasos del procedimiento de acondicionamiento y la subsiguiente fuerza de unión. Hasta donde sabemos, no hay imágenes claras previas de microscopio electrónico de barrido altamente ampliadas para la dentina y los componentes y constituyentes de la dentina con y sin diferentes tratamientos. El estudio in vitro actual sugiere la naturaleza compleja de la dentina como sustrato que debe tratarse con cuidado, especialmente en los procedimientos sensibles a la técnica, tal como las restauraciones adhesivas.

Development, in vitro biocompatibility, and antitumor efficacy of acetic acid-modified Cordyceps sinensis polysaccharide nanoparticle drug delivery system

Docetaxel-loaded acetic acid conjugated Cordyceps sinensis polysaccharide (DTX-AA-CSP) nanoparticles were prepared through dialysis and their release rates in vitro, particle sizes, zeta potentials, drug loading capacities, and encapsulation efficiencies were characterized for the synthesis of AA-modified CSPs from traditional Chinese medicine Cordyceps sinensis (Berk.) Sacc. Then, the AA-modified CSPs were characterized by 1H-NMR and FT-IR. Furthermore, the biocompatibility of the delivery carrier (AA-CSP nanoparticles) was assessed on human umbilical vein endothelial cells. In vitro antitumor activity studies on DTX-AA-CSP nanoparticles were conducted on the human liver (HepG2) and colon cancer cells (SW480). The DTX-AA-CSP nanoparticles were spherical and had an average size of 98.91±0.29 nm and zeta potential within the −19.75±1.13 mV. The encapsulation efficiency and loading capacity were 80.95%±0.43% and 8.09%±0.04%, respectively. In vitro, DTX from the DTX-AA-CSP nanoparticles exhibited a sustained release, and the anticancer activities of DTX-AA-CSP nanoparticles against SW480 and HepG2 were significantly higher than those of marketed docetaxel injection (Taxotere®) in nearly all the tested concentrations. The AA-CSP nanoparticles showed good biocompatibility. This study provided a promising biocompatible delivery system for carrying antitumor drugs for cancer therapy

Antimicrobial activity of chitosan coatings and films against Listeria monocytogenes on black radish / Actividad antimicrobiana de coberturas y películas de quitosano contra Listeria monocytogenes en rábano negro

The antibacterial activity of chitosan coatings prepared with acetic or lactic acid, as well as of composite chitosan-gelatin films prepared with essential oils, was evaluated in fresh shredded black radish samples inoculated with Listeria monocytogenes ATCC 19115 and L. monocytogenes ATCC 19112 during seven days of storage at 4 °C. The chitosan coating prepared with acetic acid showed the most effective antibacterial activity. All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of L. monocytogenes on black radish, although a higher inhibition of pathogens was achieved at higher concentrations of chitosan. The antimicrobial effect of chitosan films was even more pronounced with the addition of essential oils. Chitosan-gelatin films with thyme essential oils showed the most effective antimicrobial activity. A reduction of 2.4 log10 CFU/g for L. monocytogenes ATCC 19115 and 2.1 log10 CFU/g for L. monocytogenes ATCC 19112 was achieved in the presence of 1% chitosan film containing 0.2% of thyme essential oil after 24 h of storage.

Se evaluó la actividad antimicrobiana de coberturas del quitosano y de películas compuestas de quitosano-gelatina en muestras frescas de rábano negro cortado inoculadas con las cepas de Listeria monocytogenes ATCC 19115 y ATCC 19112, almacenadas durante 7 días a 4 °C. Las primeras fueron preparadas con ácido acético o ácido láctico, las segundas con aceites esenciales. Las coberturas de quitosano preparadas con ácido acético mostraron la actividad antimicrobiana más eficaz. Todas las formulaciones de películas de quitosano exploradas mostraron una fuerte actividad antimicrobiana sobre el crecimiento de L. monocytogenes, aunque la mayor inhibición de estos patógenos se logró con las mayores concentraciones de quitosano. La actividad antimicrobiana de las películas de quitosano fue mayor con la adición de aceite esencial. Las películas de quitosano-gelatina con aceite esencial del tomillo fueron las que mostraron la actividad antimicrobiana más eficiente. A las 24 h de almacenamiento, la película con 1% de quitosano y 0,2% de aceite esencial de tomillo produjo una reducción de 2,4 log10 UFC/g en L. monocytogenes ATCC 19115, y de 2,1 log10 UFC/g en L. monocytogenes ATCC 19112.

Habituation of enterotoxigenic Staphylococcus aureus to Origanum vulgare L. essential oil does not induce direct-tolerance and cross-tolerance to salts and organic acids

Enterotoxigenic Staphylococcus aureus strains that were isolated from foods were investigated for their ability to develop direct-tolerance and cross-tolerance to sodium chloride (NaCl), potassium chloride (KCl), lactic acid (LA) and acetic acid (AA) after habituation in sublethal amounts (1/2 of the minimum inhibitory concentration - 1/2 MIC and 1/4 of the minimum inhibitory concentration - 1/4 MIC) of Origanum vulgare L. essential oil (OVEO). The habituation of S. aureus to 1/2 MIC and 1/4 MIC of OVEO did not induce direct-tolerance or cross-tolerance in the tested strains, as assessed by modulation of MIC values. Otherwise, exposing the strains to OVEO at sublethal concentrations maintained or increased the sensitivity of the cells to the tested stressing agents because the MIC values of OVEO, NaCl, KCl, LA and AA against the cells that were previously habituated to OVEO remained the same or decreased when compared with non-habituated cells. These data indicate that OVEO does not have an inductive effect on the acquisition of direct-tolerance or cross-tolerance in the tested enterotoxigenic strains of S. aureus to antimicrobial agents that are typically used in food preservation.

O coração irritável nos discursos médicos anglo-americanos no fim do século XIX / Irritable heart syndrome in Anglo-American medical thought at the end of the nineteenth century

Investiga o estatuto e as condições de emergência da categoria nosológica de síndrome do coração irritável presente nos discursos médicos anglo-americanos na segunda metade do século XIX. No contexto da Guerra Civil Americana, examina elementos sócio-históricos que configuraram a atenção médica sobre os sintomas de ordem cardíaca de soldados. Destacam-se os valores morais de médicos-militares frente aos sintomas de medo em combatentes, assim como as hipóteses etiológicas britânicas e norte-americanas que consolidaram o estatuto nosológico do sofrimento dos soldados com palpitações. Propõe análise da especificidade da síndrome do coração irritável frente às categorias nosológicas do medo descritas pela nosologia psiquiátrica atual.

This paper examines the characteristics and the conditions for the emergence of the nosological category known as irritable heart syndrome to be found in Anglo-American medical literature in the second half of the nineteenth century. In the context of the American Civil War, it looks at some of the socio-historical elements, which comprised the medical care given to certain cardiac symptoms shown by soldiers. It emphasizes the moral values influencing the medical attitudes of military physicians towards symptoms of fear experienced by combatants, as well as the British and American etiological theories, which contributed to the nosological characterization of the suffering of soldiers afflicted with palpitations. Finally, it offers a brief analysis of the specific nature of the medical category known as irritable heart syndrome in the light of the categories of fear described by current psychiatric nosology.

Antibacterial Power of Sodium Hypochlorite Combined with Surfactants and Acetic Acid

The aim of this ex vivo study was to compare the antibacterial power of 1% NaOCl with 1% acetic acid, 5.25% NaOCl and two commercially available NaOCl modified with surfactants in bovine root dentin. A total of 120 dentin tubes prepared from intact bovine incisors were infected for 21 days with Enterococcus faecalis and randomly divided into six groups as follows: 5.25%NaOCl; Hypoclean; Chlor-Xtra; 1% NaOCl with 1% acetic acid; infected dentin tubes (positive control); and sterile dentin tubes (negative control). At experimental times of 0, 7, 14, 21 and 28 days, dentin chips were collected using sequential round burs with increasing diameters in separate test tubes containing 3 mL of freshly prepared BHI. Statistical analysis were performed using parametric methods (one-way ANOVA, and Bonferroni's multiple comparisons test, α=0.01). After culturing, the number of colony-forming units (CFU) was counted. All the NaOCl solutions showed small number of CFU over 28 days. ChlorXtra and Hypoclean had the smallest number of CFU at all times with greater antimicrobial efficacy than 5.25% NaOCl and 1% NaOCl solution with 1% acetic acid.

O objetivo deste estudo foi verificar o poder antibacteriano do hipoclorito de sódio a 1% acrescido do ácido acético 1%, do NaOCl 5,25%, e de duas soluções irrigadoras modificadas com surfactantes, Hypoclean e Chlor-Xtra, em tubos de dentina bovina. Um total de 120 tubos de dentina preparados a partir de incisivos bovinos foram infectados durante 28 dias com o Enterococcus faecalis, e aleatoriamente divididos em seis grupos: NaOCl 5,25%; Hypoclean; Chlor-Xtra; NaOCl 1% com ácido acético 1%; tubos de dentina infectados (controle positivo); e tubos de dentina esterilizados (controle negativo). Em períodos de tempo de 0, 7, 14, 21 e 28 dias, raspas de dentina foram coletadas usando brocas esféricas com diâmetros crescentes, e mantidas em tubos de ensaio contendo 3 mL de infusão cérebro coração (brain heart infusion). A análise dos dados foi feita com testes paramétricos (ANOVA a um fator e teste de comparações múltiplas de Bonferroni, α=1%). Após a cultura, o número de unidades formadoras de colônias (UFC) foi contado. Todas as soluções de hipoclorito de sódio mostraram pequena quantidade de UFC nos períodos por até 28 dias. Chlor Xtra e Hypoclean tiveram menor número de UFC em todos os períodos observados, com maior efetividade antimicrobiana do que o NaOCl 5,25% e do que o NaOCl a 1% com ácido acético a 1%.

Have magnesium sulfate, acetic acid, meprobamate and fluoxetine an anti-arthrogenic activity?

Atherosclerosis is a progressive inflammatory disorder of the arterial wall that is characterized by focal lipid rich deposits of atheroma with possible correlation with sedative hypnotics in decreasing atherogenesis. This study was performed in Al-Kadhimiya teaching hospital from February 2009 to June 2009 on sixty healthy males who were allocated to six groups. Each group was given one of the following agents: Magnesium sulfate [MgSo4], acetic acid, Meprobamate, Fluoxetine in addition to Simvastatin and water. Clinical manifestations like [arterial blood pressure, radial pulsation], lipid profiles [serum cholesterol, triglycerides, HDL, LDL and VLDL] total free radicals and platelets function tests are the parameters used in this study. All the tested agents reduce both the serum cholesterol concentration and total blood free radicals significantly; also they decrease both platelet count and adhesion test significantly. Both MgSo4 and Meprobamate lowered blood pressure and serum triglyceride concentration significantly, at the same time HDL concentration significantly changed by Fluoxetine when these parameters measured before and after treatment for 15 days. MgSo4, acetic acid, Meprobamate and Fluoxetine were found to have anti-arthrogenic activity and the possibility to be used clinically in atherosclerosis

A comparative scanning electron microscopy evaluation of smear layer removal with apple vinegar and sodium hypochlorite associated with EDTA

OBJECTIVE: The purpose of this study was to evaluate by scanning electron microscopy (SEM) the removal of smear layer from the middle and apical root thirds after use of different irrigating solutions. MATERIAL AND METHODS: Forty roots of permanent human teeth had their canals instrumented and were randomly assigned to 4 groups (n=10), according to the irrigating solution: apple vinegar (group A), apple vinegar finished with 17 percent ethylenediaminetetraacetic acid (EDTA) (group B), 1 percent sodium hypochlorite (NaOCl) finished with 17 percent EDTA (group C) and saline (group D - control). After chemomechanical preparation, the roots were cleaved longitudinally and their middle and apical thirds were examined by SEM at ×1,000 magnification. Two calibrated examiners (kappa=0.92) analyzed the SEM micrographs qualitatively attributing scores that indicated the efficacy of the solutions in removing the smear layer from the surface of the dentin tubules (1 - poor, 2 - good and 3 - excellent). Data from the control and experimental groups were analyzed by the Kruskal-Wallis and Dunn's test, while the Wilcoxon test was used to compare the middle and apical thirds of the canals within the same group (a=0.05). RESULTS: The middle third presented less amount of smear layer than the apical third, regardless of the irrigant. There was statistically significant difference (p=0.0402) among the groups in the middle third. In the apical third, the apple vinegar/EDTA group showed the greatest removal of smear layer (p=0.0373). CONCLUSION: Apple vinegar associated or not with EDTA was effective in removing smear layer when used as an endodontic irrigant.

Effects of milk curd on saliva secretion in healthy volunteer compared to baseline, 2% pilocarpine and equivalent pH adjusted acetic acid solutions.

Background: Dry mouth is a common clinical problem, and different products have been proposed to improve it. In this investigation, the effects of "milk curd" on the amount of saliva secretion were studied. Materials and Methods: A total of 32 patients (aged 20-30) were selected from healthy volunteers. Milk curd concentrations of 0.5, 1, 2 and 4%, and 2% pilocarpine were prepared as drops. The impact of the drugs on the saliva weight was assessed after 1-5 min. To determine the effects of the pH of the milk curd on the amount of saliva secretion, different concentrations of acetic acid were used. Results: At the end of the first minute, the differences between the data for all groups were statistically significant, and the difference between the 2% and 4% milk curd groups was higher than the others (P < 0.0001). The differences in the amount of the saliva secreted at the end of the second minute between the baseline and 4% milk curd groups and between the 0.5% and 4% MC groups were significant (P = 0.006 and P = 0.025, respectively). In total, there was no significant difference between the effect of various pH treatments and the amount of baseline saliva secretion. Conclusion: Milk curd has a significant local impact, and the saliva increase depends on the dose. It seems that this effect is not only related to its acidic taste. As a result, factors other than pH are involved in the effect.

Effects of intraperitoneal injection of phenol, glycerin and acetic acid on neoplastic ascitis in guinea pigs / Efeitos da injeção intraperitoneal de fenol, glicerina e ácido acético na ascite neoplásica em cobaias

PURPOSE: To investigate the histolytic action of a solution composed by phenol, glycerin and acetic acid on neoplastic ascitis in guinea pigs. METHODS: Thirty-two guinea pigs were used. The animals were randomly distributed in experimental and control groups, and the effects of the peritoneal injection of the testing solution were studied. Saline solution was used for the control groups. Biochemical and anatomopathological (heart, lungs, kidneys, spleen and peritoneal serous membrane) were evaluated at 24 hours and 4 weeks of development. RESULTS: It was observed that solution E, when infused into the peritoneal cavity, caused no clinical, histological or laboratory alterations in these animals when compared to those in the control group. CONCLUSION: Given our results, it would be interesting to study the effects of the proposed solution on cases with experimental neoplastic ascites with a later view to treating it in humans.

OBJETIVO: Investigar a ação hìstolítica de uma solução composta de fenol, glicerina e ácido acético na ascite neoplásica em cobaias. MÉTODOS: Foram utilizadas 32 cobaias, distribuídas por sorteio, em grupos experimentais e controles e estudados os efeitos da injeção peritonial da solução teste. Nos grupos controles empregou-se solução fisiológica. Foram estudadas alterações bioquímicas, anatomopatológicas (coração, pulmões, rins, baço e serosa peritonial), com 24 horas e 4 semanas de evolução. RESULTADOS: Verificou-se que a solução E quando instilada na cavidade peritonial não provocou nenhuma alteração clinica, histologica ou laboratorial nestes animais, quando comparados com o grupo controle. CONCLUSÃO: Frente aos resultados obtidos, consideramos interessante estudar os efeitos da solução proposta em casos de ascite neoplásica experimental em animais, com posterior estudo em seres humanos.

Atividade antimicrobiana de soluções de ácido acético de diferentes tipos e procedências sobre Candida albicans / Antimicrobial activity of acetic acid of different types and origins on Candida albicans

O objetivo deste trabalho foi avaliar a atividade antimicrobiana de soluções de ácido acético (vinagre) sobre cepas de Candida albicans. Utilizaram-se 21 isolados bucais de Candida albicans e Candida albicans ATCC 18804 e soluções de ácido acético (vinagre branco agrin Belmont, tinto Castelo, branco de arroz Daiti, maçã Belmont, branco Castelo, branco Neval, maçã Carrefour, álcool Castelo, tinto Belmont e tinto Neval). Placas de Petri com ágar Sabouraud dextrose e concentrações seqüenciais de cada solução foram preparadas. As suspensões celulares padronizadas foram semeadas nas placas com auxílio de inoculador de Steers em duplicata e incubadas por 24 horas a 37°C. A máxima diluição fungicida (MDF) das cepas frente às diferentes concentrações das soluções-teste foi verificada. Concluiu-se que todas as soluções de ácido acético testadas apresentaram efetividade contra cepas de Candida albicans em baixas concentrações.

Giardiacidal activity of lemon juice, vinifer and vinegar on Giardia intestinalis cysts.

The giardiacidal efficacy of simple disinfecting materials, ie lemon juice, vinifer, and vinegar, for uncooked foods with Giardia cysts was investigated to help travelers in Giardia-endemic areas. The cysts were obtained from stools of individuals with Giardia intestinalis infection by modified sucrose gradient procedure. A pooled batch of 3 x 10(4)/ml Giardia cysts was made from all specimens. The cysts were kept at 4 degrees C until use. Before each experiment, the number of cysts was determined by hemocytometer. Two sets of Eppendorf tubes were used for the experiments, one set at 4 degrees C and one at 24 degrees C. One thousand microliters each of lemon juice, vinifer, or vinegar was poured into each tube, and 1,000 microl of Giardia cysts were added. Variables were disinfectant materials, temperature, and time of exposure. Cyst viability 140 was determined by eosin inclusion procedure. Viability of at least 250 cysts in each tube at 0, 0.5, 1, 2 and 3 hours after the beginning of the experiments was determined. The mean giardiacidal activity at 4 degrees C after 3 hours for lemon juice, vinifer, and vinegar was 18.9, 12.8, and 28.4%, and at 24 degrees C, 28.3, 16.2, and 40.6%, respectively. In conclusion, the giardiacidal activity of vinegar was more than the other materials, and as exposure time and temperature increased, giardiacidal activity also increased; the highest giardiacidal activity of vinegar was at 3-hours exposure at 24 degrees C.

Some factors affecting Stellantchasmus falcatus metacercaria in laboratory.

Killing factors, various temperatures and solutions were studied in the laboratory on Stellantchasmus falcatus metacercaria in half-beaked fish (Dermogenus pusillus). Killing criteria followed the Movability Index from 1.000 within 24 hours. The metacercariae were collected from Chiang Mai moat. They were incubated in 0.85 % NaCl at -20 degrees C, room temperature, 4 degrees, 37 degrees, and 65 degrees C. The in vitro investigation showed that at -20 degrees C and 65 degrees C, the worms were killed within 18 and 2 hours, respectively, while other temperatures produced no effect. The solutions investigated were NaCl (10, 20, 30, and 40%), lemon juice (25, 50, 75, and 100%), acetic acid (5, 10, 20, and 30%), vinegar (1, 3, and 5%) and water as a control. The worms were killed in NaCl at 20, 30, and 40% within 12, 6, and 2 hours, respectively. Acetic acid at 5% and 10% killed the metacercaria within 12 and 6 hours while at 20% and 30%, within 2 hours. The killing effect of 3% vinegar was found within 18 hours and of 5% vinegar within 12 hours. Lemon juice showed no killing effect.

Cholinergic-NO-cGMP mediation of sildenafil-induced antinociception.

Acetylcholine and cholinomimetic agents with predominant muscarinic action are known to increase the concentration of cGMP by activation of nitric oxide signaling pathway in the nociceptive conditions. The present study was aimed to investigate the NO-cGMP-PDE5 pathway in nociceptive conditions in the experimental animals. Nociceptive threshold was assessed by acetic acid-induced writhing assay (chemonociception) or carrageenan-induced hyperalgesia. Sildenafil [1-5 mg/kg, ip, 50-200 microg/paw, intraplantar (ipl)] produced dose dependent antinociception in both the tested models. Coadministration of acetylcholine (50 mcg/paw, ipl) or cholinomimetic agent, neostigmine (0.1 mcg/kg, ip and 25 ng/paw, ipl) augmented the peripheral antinociceptive effect of sildenafil. This effect was sensitive to blockade by L-NAME (20 mg/kg, ip, 100 microg/paw, ipl), a non-selective NOS inhibitor and methylene blue (1 mg/kg, ip), a guanylate cyclase inhibitor, which per se had little or no effect in both the models of nociception. Further, the per se analgesic effect of acetylcholine and neostigmine was blocked by both L-NAME and methylene blue in the models of nociception, suggesting the activation of NO-cGMP pathway. Also, both L-NAME and methylene blue blocked the per se analgesic effect of sildenafil. These results indicate the peripheral accumulation of cGMP may be responsible for antinociceptive effect, and a possible interaction between cholinergic agents and PDE5 system in models of nociception.

The influence of vinegars on exposure of dentinal tubules: a SEM evaluation

A hipersensibilidade dentinária cervical é uma condição dolorosa muito comum nos consultórios. A dieta tem sido bastante associada ao seu aparecimento, assim como a sua persistência após o tratamento periodontal. o objetivo deste trabalho foi avaliar in vitro a influência dos vinagres na remoção de "smear layer" e exposição dos túbulos dentinários. Dentes de humanos foram instrumentados com curetas Gracey para a remoção do cemento e formação de "smear layer". Foram obtidas amostras de dentina com 3 mm2, divididas entre o grupo controle (água destilada) e cinco grupos de vinagre: branco, maçã, arroz, vinho branco e balsâmico. Cada grupo incluiu duas formas de aplicação da substância, tópica ou por fricção. Após o preparo para observação em MEV (microscopia eletrônica de varredura), as fotomicrografias foram avaliadas por um examinador previamente calibrado utilizando um índice apropriado. O teste de Kruskal-Wallis indicou influência significativa dos vinagres na remoção de "smear layer". Foi constatada uma diferença estatística significante entre os grupos maçã, branco e arroz e o grupo controle (p < 0,05). O teste de Mann-Whitney, porém, indicou que a remoção de "smear layer" não variou para nenhuma das substâncias segundo a forma de aplicação. Conclui-se que os vinagres podem remover "smear layer" da superfície radicular e expor túbulos dentinários, não sendo influenciados pelo tipo de aplicação. Dentre os tipos de vinagres testados, o balsâmico esteve associado a menor remoção de "smear layer" após ambas as formas de aplicação.

Evaluation of different chlorine based disinfectantes and vinegar agaisnt Vibrio cholerae present in lettuce

Folhas de alface foram contaminadas com uma suspensäo de V. cholerae 01 contendo aproximadamente 10(6) UFC/ml. Amostras de 25g foram imersas durante 15 minutos em soluçöes de hipoclorito de sódio (NaOCl) e 3 diferentes produtos comerciais à base de di-cloro-isocianurato de sódio, todas elas contendo 100mg/l de cloro residual livre. Amostras de 25g também foram imersas por 15 e 30 minutos em soluçäo de NaOCl contendo 200mg/l de cloro ativo. Amostras similares foram imersas em soluçöes de vinagre comercial a 2 p/cento, 4 p/cento e 6 p/cento (v/v) e avaliadas após 15 minutos de tratamento. Após desinfecçäo, os resíduos das diferentes substâncias químicas foram neutralizados e enumerada a populaçäo de V. cholerae, determinando-se também a populaçäo da bactéria em folhas näo-tratadas. O vinagre foi o melhor dos produtos avaliados, seguido em ordem decrescente de eficiência pelos compostos à base de di-cloro-isocianurato de sódio e NaOCl. Em geral a reutilizaçäo das soluçöes de cloro näo affetou sua eficiência