Determination of sulfur compounds in biological desulfurization system by high performance liquid chromatography / 生物工程学报

Biological desulfurization is a process in which sulfur compounds are removed from gas and oil using microorganisms. It is a simple process that has mild operating conditions, high desulfurization efficiency, low energy consumption and less environmental pollution. However, there is still a lack of simple and efficient analytical methods for quantitatively analyzing the sulfur compounds in the biological desulfurization process. In order to solve this problem, the analytical method for the simultaneous determination of sulfite, thiosulfate and sulfide in biological desulfurization solutions by pre-column fluorescence derivation using high performance liquid chromatography (HPLC) was developed. The standard curves of sulfur species in this analytical method had good linear relationships with correlation coefficients of 0.999 5, 0.999 7, and 0.999 7 for sulfite, thiosulfate and sulfide, respectively. The detection limits of these sulfur compounds were 0.000 6, 0.000 7 and 0.001 1 μmol/L; the range of recovery rates were 98.17 to 101.9%, 100.9 to 102.6%, and 101.1 to 104.2%; which had good repeatability and stability. The analytical method was simple, efficient and accurate, and could be used to simultaneously determine the sulfur compounds in different biological desulfurization systems.

Accuracy of a portable breath meter test for the detection of halitosis in children and adolescents

OBJECTIVES: This study aimed to determine the accuracy of the Breath-Alert™ portable breath meter (BA) for the detection of halitosis in children and adolescents, considering the organoleptic test (OT) as the gold standard in this assessment. METHODS: A cross-sectional study was conducted on 150 children (aged 6-12 years). OT was performed by three independent examiners on a single occasion, obtaining three scores of 0-5 points on the Rosenberg's organoleptic scale. The median of the three evaluations for each child was used for analysis. BA was used according to the manufacturer's instructions, with breath odor scored from 0-5 points. Scores ≥2 on both tests were considered indicative of halitosis. RESULTS: A total of 26 (17.3%) and 23 (15.3%) children were detected with halitosis on the OT and BA tests, respectively. The sensitivity and specificity of the BA scores for the detection of halitosis were 80.76% and 98.38%, respectively. The positive and negative predictive values for BA were 91.3% and 96.06%, respectively. CONCLUSION: In the present study involving children, who require fast, practical examinations, BA proved to be an auxiliary tool to OT for the detection of halitosis in the practice of pediatric dentistry, demonstrating high sensitivity and specificity.

Percepção sensorial do off-odor em carnes bovinas irradiadas em embalagens á vácuo contendo carvão ativado / Off-odor perception in irradiated beef vacuum packaged with charcoal

Objetivou-se avaliar a utilização de carvão ativo na redução de compostos voláteis responsáveis pelo off-odor de carnes bovinas irradiadas. Para tal, contrafilés bovinos, embalados a vácuo, com e sem carvão ativo, e irradiados (1, 2 e 3 kGy), foram analisados quanto a formação de compostos de enxofre e quanto a percepção sensorial de off-odor. O único composto de enxofre identificado nas amostras foi o dimetil sulfeto (DMS), sendo encontrado em menor concentração nas amostras irradiadas com carvão ativo na embalagem. Independentemente da utilização do carvão, os painelistas perceberam o off-odor das carnes irradiadas em qualquer dose quando comparado à carne não-irradiada. Quando foi comparado as carnes irradiadas com carvão em relação àquelas irradiadas sem carvão, os painelistas foram capazes de identificar o off-odor apenas nas amostras irradiadas com 1 kGy. Conclui-se que o carvão ativo reduziu a concentração de DMS na embalagem de carnes irradiadas.

Estudo longitudinal da halitose por meio da cromatografia gasosa / Longitudinal study of halitosis through gas chromatography

Objetivos: correlacionar os exames organolépticos (método subjetivo) e a cromatografia gasosa (método objetivo) para diagnóstico conclusivo da halitose e avaliar o comportamento dos compostos sulfurados voláteis (CSVs) durante o manuseio clínico desta patologia. Metodologia: estudo longitudinal com 19 pacientes submetidos ao diagnóstico de halitose, com exames organolépticos (EOt1) e cromatografia gasosa (ECGt1) realizados durante a consulta inicial, com todos os pacientes oriundos do município de Ijuí, Rio Grande do Sul. Todos os 38 exames complementares foram confrontados entre si, por meio do teste estatístico Qui-Quadrado de independência. Para acompanhamento clínico da efetividade do tratamento da halitose e, consequentemente, análise do comportamento dos CSVs, outros quatro exames de cromatografia gasosa (ECGt2, ECGt3, ECGt4 e ECGt5) foram realizados para cada paciente, e todos (95) comparados entre si, pelo teste de Wilcoxon. Resultados: a correlação entre EOt1 e ECGt1 obteve concordância em 78,9% dos casos, indicando forte associação (p = 0,002) entre ambos. Ao avaliar a monitorização dos compostos sulfurados H2S, CH3SH e (CH3)2S, todos envolvidos em alguma fase da gênese da halitose, houve significativa redução de todos os compostos. Conclusões: os exames de cromatografia gasosa (objetivo) e organoléptico (subjetivo) são equivalentes para diagnóstico inicial da halitose, pois apresentaram correlação estatística significante. Em relação à monitorização do tratamento da halitose, a cromatografia gasosa se mostrou eficiente, apresentando altos índices de redução de todos os CSVs. (AU)

Objectives: To correlate organoleptic evaluations (subjective method) and gas chromatography (objective method) for the conclusive diagnosis of halitosis and to examine the behavior of volatile sulfur compounds (VSC) during the clinical management of this pathology. Methodology: Longitudinal study with 19 patients diagnosed with halitosis through organoleptic evaluations (EOt1) and gas chromatography (ECGt1), both applied during the initial appointment. All patients were from the city of Ijuí, located in the state of Rio Grande do Sul, Brazil. All 38 complementary analyses were compared using the chi-square test of independence. Regarding the clinical follow-up on the effectiveness of halitosis treatment, and consequently the analysis of VSC behavior, four other gas chromatography tests (ECGt2, ECGt3, ECGt4, and ECGt5) were conducted with each patient, and all (95) were compared using the Wilcoxon test. Results: The correlation between EOt1 and ECGt1 showed concordance in 78.9% of cases, indicating a strong association (p=0.002). The evaluation of the monitoring of sulfate compounds H2S, CH3SH, and (CH3) 2S, which are all involved in some phase of the halitosis genesis, showed a significant reduction of all compounds. Conclusions: The gas and chromatography and organoleptic tests are equivalent for the initial diagnosis of halitosis because they presented significant statistical correlation. Regarding the monitoring of halitosis treatment, gas chromatography was efficient, presenting high reduction rates of all VSC. (AU)

Clinical evaluation of cetylpyridinium chloride-containing mouthwash in halitosis

Halitosis is a very common disease that affects the majority of the population and is characterized by unpleasant odor during expiration. Anaerobic bacteria produce a range of malodorous substances including volatile sulfur compounds. To reduce oral malodor, the amount of oral microorganisms should be managed through brushing, scraping, and use of antibacterial agents. In this study, a mouthwash containing 0.05% cetylpyridinium chloride was tested on 22 candidates with oral malodor for two weeks to confirm oral malodor reduction through the use of antibacterial mouthwashes. Volatile sulfur compound measurements were significantly lower after using the mouthwash than before using it; thus, the mouthwash effectively reduced oral malodor.

Effect of Polyethylene Terephthalate Tongue Scraper on Oral Levels of Volatile Sulfur Compounds: a randomized clinical trial / Efeito do raspador de língua de polietilenotereftalato nos níveis orais de compostos sulfurados voláteis: um ensaio clínico randomizado

Objective: To evaluate the effect of Polyethylene Terephthalate (PET) tongue scraper on the volatile sulfur compound (VSC) levels. Material and Methods: A randomized, controlled, parallel design was used in this study. Out of the 48 volunteers from Dentistry Department of the Federal University of Sergipe, 40 subjects who met the inclusion criteria were randomly divided into 4 groups (n=10): G1 (control), rinsing of distilled water solution (WS); G2, WS and tongue coating removal (TCR) with toothbrush; G3, WS and TCR with a commercial tongue scraper; and G4, WS and TCR with PET tongue scraper. PET bottles were cut with a rectangular shape (1.0 cm wide x 20 cm long) to obtain PET tongue scraper. The VSC measurements were performed before (T0) and immediately after (T1) each therapy by portable sulfide monitor. Data (ppb) were submitted to Wilcoxon test (α=0.05). The differences between T0 and T1 were calculated and percentage values were assigned. Data (percentage) were submitted to ANOVA and Tukey test (α=0.05). Results: All 40 selected subjects completed the study. All groups reduced significantly the VSC levels after therapy (P<0.01). ANOVA indicated a significant difference among groups (P<0.001). The Tukey test showed that G1 (reduction of 21%) was similar to G2 (31%); G2 was similar to G3 (42%) and different from G4 (52%); G3 and G4 were similar. Conclusion: PET tongue scraper was similar to commercial tongue scraper and provided higher reductions of VSC levels than the toothbrush. (AU)

Objetivo: Avaliar o efeito do raspador de língua de polietilenotereftalato (PET) nos níveis de compostos sulfurados voláteis (CSVs). Material e Métodos: Um desenho paralelo, controlado e randomizado foi empregado neste estudo. Dos 48 voluntários do Departamento de Odontologia da Universidade Federal de Sergipe, 40 atenderam ao critério de inclusão e foram distribuídos aleatoriamente em 4 grupos (n=10): G1 (controle), bochecho com solução de água destilada (SA); G2, SA e remoção da saburra lingual (RSL) com escova dental; G3, SA e RSL com um raspador de língua comercial; e G4, SA e RSL com raspador de língua PET. Garrafas PET foram recortadas com uma forma retangular (1,0 cm de largura x 20 cm de comprimento) para obtenção dos raspadores de língua PET. As mensurações de CSVs foram realizadas antes (T0) e imediatamente após (T1) cada terapia usando um monitor portátil de enxofre. Os dados (ppb) foram submetidos ao teste de Wilcoxon (α=0,05). As diferenças entre T0 e T1 foram calculadas e transformadas em valores percentuais de redução. Os dados (percentuais) foram submetidos à ANOVA e ao teste de Tukey (α=0,05). Resultados: Todos os 40 indivíduos selecionados completaram o estudo. Em todos os grupos houve redução significante dos níveis de CSVs após terapia (P<0,01). ANOVA indicou uma diferença significante entre grupos (PP<0,001). O teste de Tukey mostrou que G1 (redução de 21%) foi semelhante a G2 (31%); G2 foi semelhante a G3 (42%) e diferente de G4 (52%); G3 e G4 foram semelhantes. Conclusão: O raspador de língua PET foi semelhante ao raspador de língua comercial e proporcionou maiores reduções de CSVs do que a escova dental. (AU)

Research on control effect of sulfoxaflor and flonicamid on Lonicera japonica / 中国中药杂志

The study was aimed to determine the efficacy of two pesticides in the control of aphids in Lonicera japonica, and study the applicability of pesticides in L. japonica. The number of insects was counted before and 2, 3, 7 and 10 days after the application of pesticide in the test area within different dosage groups. The method was 5-point sampling method. Five aphids on the L. japonica branches were selected, then the number of insects was recorded. The effect of the two pesticides on the control rate of aphid was more than 80% at 1 d after application. The results showed that the two pesticides had good efficacy. After 7 days and 10 days, the control effect was 100%. After 1 day of spraying, the effect of the two pesticides on the control of L. japonica aphids was more than 80%, which was higher than that of the control agent. The results showed that the two pesticides had good and fast effect. After 7 days and 10 days of spraying, the control effect was 100%. The control effect of two kinds pesticides for aphid sprayed in recommended dose on the L. japonica is good and showed no hytotoxicity.

Oral malodor-reducing effects by oral feeding of Weissella cibaria CMU in Beagle dogs / 대한수의학회지

This study assessed the effects of Weissella cibaria (W. cibaria) CMU on oral health in male and female beagles (n = 18) by measuring oral malodor and periodontal disease-related parameters (calculus, plaque, and gingivitis indices). Oral malodor and indicators of periodontal disease were assessed in five treatment groups: negative control (scaling and 0.24 mg of maltodextrin, n = 3), positive control (0.24 mg of maltodextrin, n = 3), and W. cibaria CMU groups (each n = 4) at low (CMU-L, 2 × 10⁷ colony forming unit [CFU]), medium (CMU-M, 2 × 10⁸ CFU), and high (CMU-H, 2 × 10⁹ CFU) concentrations. After feeding with W. cibaria CMU for 6 weeks, total volatile sulfur compound concentrations in the CMU-L (2.0 ± 1.04 ng/10 mL), CMU-M (2.4 ± 1.05 ng/10 mL), and CMU-H (2.6 ± 1.33 ng/10 mL)groups were significantly lower than in the positive control group (3.2 ± 1.65 ng/10 mL). Also, CMU-L (1.4 ± 0.83 ng/10 mL) and CMU-H (1.9 ± 1.14 ng/10 mL) groups had methyl mercaptan levels lower than that in the positive control group (2.4 ± 1.21 ng/10 mL) at week 2. The plaque index was significantly lower in the CMU-H group (4.5 ± 0.28) than in the positive control group (5.9 ± 1.08) at week 6. W. cibaria CMU could be useful as a novel oral hygiene probiotics for reducing volatile sulfur compounds production and inhibiting plaque growth in companion animals.

The curative effects of methylsulfonylmethane against glycerol-induced acute renal failure in rats

Abstract The present study was performed to explore the curative effect of Methylsulfonylmethane (MSM) in an experimental model of myoglobinuric acute renal failure (ARF). In this experimental model, Rats were injected with 50% glycerol (10 mL/kg, im) followed by an hour later and daily in the next six days by MSM (400 mg/kg) or saline. Kidney's function (urea and creatinine), and reduced glutathione were analyzed. A renal failure produced by glycerol injection, with a significant increase of blood urea and serum creatinine was observed. Rats that received MSM in addition to glycerol had significantly lower blood urea and serum creatinine levels compared to those receiving glycerol alone. However, glutathione has markedly increased after MSM treatment. The effect is probably due to the antioxidant activity of MSM. This may provide therapeutic opportunities for treating humans, myoglobinuric ARF.

Assessment of Volatile Sulfur Compounds in Adult and Pediatric Chronic Tonsillitis Patients Receiving Tonsillectomy

OBJECTIVES.: To study the volatile sulfur compound (VSC) concentration profile in chronic tonsillitis patients before and after tonsillectomy, and to evaluate the difference between adult and pediatric (children and adolescents) patients. METHODS.: Thirty adult patients (older than 20 years old) and 30 pediatric patients (younger than 20 years old) who were assigned to get tonsillectomy due to chronic tonsillitis were enrolled in this prospective nonrandomized clinical study. The concentrations of the three main VSCs related to halitosis (hydrogen sulfide, methyl mercaptan, and dimethyl sulfide) were assessed in each patient using a portable chromatograph (Oral ChromaTM) at 1 day before operation, postoperative 1 day, 1 week, and 2 weeks. RESULTS.: Average concentration of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide preoperatively were 99.5 ppb, 24.6 ppb, and 9.45 ppb in adult patients, and 97.4 ppb, 26 ppb, and 10.5 ppb in pediatric patients, respectively. The concentrations of the three VSCs in both groups were highest in first day after surgery, and decreased signigicantly after 2 weeks compared to preoperative values (P < 0.001). There was no significant difference of the concentration of the three VSCs between adult and pediatric patients in any time point. CONCLUSION.: The concentrations of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide decreased significantly after tonsillectomy in chronic tonsillitis patients. The concentrations of the three VSCs were not significantly different between pediatric and adult patients before and after tonsillectomy.

Assessment of the accuracy of portable monitors for halitosis evaluation in subjects without malodor complaint. Are they reliable for clinical practice?

Abstract Halitosis is defined as a foul odor emanated from the oral cavity, with great impact in quality of life and social restraints. Recently, the use of Breath Alert™ in research increased significantly. Halimeter™, another portable device, is often used in clinical practice. Nevertheless, not many studies have verified the accuracy and compared the results of both devices simultaneously. Objective: To verify the accuracy of Breath Alert™ and Halimeter™ in patients without chief complaint of halitosis, using the organoleptic test (OT) as "gold standard." The second aim was to verify whether their concomitant use could enhance the diagnostic accuracy of halitosis. Material and Methods: A cross-sectional analytical study was performed. The quality of expired air of 34 subjects without chief complaint of halitosis was assessed. Two experienced examiners carried out the OT. Afterward, a third blinded examiner performed Halimeter™ (HT) and Breath Alert™ (BA) tests. Results: The OT identified halitosis in 21 subjects (62%). The area under the ROC curve (95% confidence interval) was 0.67 (0.48-0.85) and 0.54 (0.34-0.75) for HT and BA, respectively. The accuracy for HT and BA was 59% and 47%, respectively. The combined usage of HT and BA provided 11 positive results, being 9 subjects (43%) out of the total of 21 positive cases. Conclusions: Halimeter™ and Breath Alert™ were not able to diagnose halitosis in non-complainer subjects at the same level as the organoleptic examination, since their accuracy were low. Our results suggest that such portable devices are not reliable tools to assess halitosis and may neglect or misdiagnose a considerable number of patients in clinical practice.

In vitro effects of Melaleuca alternifolia essential oil on growth and production of volatile sulphur compounds by oral bacteria

ABSTRACT Objective Halitosis can be caused by microorganisms that produce volatile sulphur compounds (VSCs), which colonize the surface of the tongue and subgingival sites. Studies have reported that the use of natural products can reduce the bacterial load and, consequently, the development of halitosis. The aim of this study was to evaluate the antimicrobial activity of the essential oil of Melaleuca alternifolia on the growth and volatile sulphur compound (VSC) production of oral bacteria compared with chlorhexidine. Material and Methods The effects of these substances were evaluated by the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) in planktonic cultures of Porphyromonas gingivalis and Porphyromonas endodontalis. In addition, gas chromatography analyses were performed to measure the concentration of VSCs from bacterial cultures and to characterize M. alternifolia oil components. Results The MIC and MBC values were as follows: M. alternifolia - P. gingivalis (MIC and MBC=0.007%), P. endodontalis (MIC and MBC=0.007%=0.5%); chlorhexidine - P. gingivalis and P. endodontalis (MIC and MBC=1.5 mg/mL). M. alternifolia significantly reduced the growth and production of hydrogen sulfide (H2S) by P. gingivalis (p<0.05, ANOVA-Dunnet) and the H2S and methyl mercaptan (CH3SH) levels of P. endodontalis (p<0.05, ANOVA-Dunnet). Chlorhexidine reduced the growth of both microorganisms without altering the production of VSC in P. endodontalis. For P. gingivalis, the production of H2S and CH3SH decreased (p<0.05, ANOVA-Dunnet). Conclusion M. alternifolia can reduce bacterial growth and VSCs production and could be used as an alternative to chlorhexidine.

Keratinolytic abilities of Micrococcus luteus from poultry waste

Keratinolytic microorganisms have become the subject of scientific interest due to their ability to biosynthesize specific keratinases and their prospective application in keratinic waste management. Among several bacterial classes, actinobacteria remain one of the most important sources of keratin-degrading strains, however members of the Micrococcaceae family are rarely scrutinized in regard to their applicatory keratinolytic potential. The tested Micrococcus sp. B1pz isolate from poultry feather waste was identified as M. luteus. The strain, grown in the medium with 1–2% chicken feathers and a yeast extract supplement, produced keratinases of 32 KU and lower level of proteases, 6 PU. It was capable to effectively decompose feathers or “soft” keratin of stratum corneum, in contrast to other “hard” hair-type keratins. The produced keratinolytic enzymes were mainly a combination of alkaline serine or thiol proteases, active at the optimum pH 9.4, 55 °C. Four main protease fractions of 62, 185, 139 and 229 kDa were identified in the crude culture fluid. The research on the auxiliary role of reducing factors revealed that reducing sulfur compounds could be applied in keratinolysis enhancement during enzymatic digestion of keratin, rather than in culture conditions. The presented M. luteus isolate exhibits a significant keratinolytic potential, which determines its feasible applicatory capacity towards biodegradation of poultry by-products or formulation of keratin-based feed components.

Emissão de amônia de veículo automotor leve e sua importância para a Saúde Ambiental / Ammonia emission from light duty vehicle and its importance for the environmental health

Introdução - A amônia (NH3) é um poluente atmosférico cuja emissão é em parte provocada por atividades antrópicas. A geração de energia através da queima de combustíveis é uma dessas atividades, dentro da qual, o setor de transporte e principalmente os veículos automotores rodoviários são uma fonte considerável das emissões de poluentes. Além de afetar diretamente a saúde humana, a amônia participa de reações na atmosfera que geram como poluente secundário, material particulado fino. Objetivo - Verificar, em veículo com motor de ignição por centelha (ciclo Otto), os valores da emissão de amônia, utilizando os combustíveis gasool 22 (gasolina contendo 22 por cento em volume de etanol anidro), etanol hidratado carburante (EHC) e gás natural veicular (GNV), com e sem a presença de elemento catalítico (catalisador). Métodos - O veículo foi ensaiado em dinamômetro de chassis, seguindo ciclo de condução e amostragem dos poluentes conforme Norma ABNT NBR 6601, para medição da emissão de escapamento, pela Norma ABNT NBR 7024, para medição de autonomia; e seguindo os ciclos de condução congestionamento (NYCC) e agressivo (US-06), adotados pela Agência de proteção ambiental dos EUA (USEPA). Além dos métodos de análise dos gases prescritos nessas Normas, foi utilizado o método FTIR (Fourier Transform InfraRed) para medição de NH3 e de N2O. Resultados - As emissões de amônia encontradas foram: média de 1,06 ± 0,03 mg/km, 1,34 ± 0,42 mg/km e 1,22 ± 0,59 mg/km antes do catalisador; e de 4,16 ± 0,65 mg/km, 3,80 ± 1,60 mg/km e 3,88 ± 0,06 mg/km nas medições após o catalisador, respectivamente para os combustíveis GNV, EHC e gasool 22. Os valores médios de emissão de amônia obtidos nos ensaios com a utilização de gasool 22 com teores de enxofre de 50 ppm e 350 ppm foram respectivamente de 3,26 ± 0,51 mg/km e 3,88 ± 0,06 mg/km. Os valores médios de emissão de amônia para os ciclos FTP-75, NYCC e US-06, foram respectivamente: 4,16 ± 0,65 mg/km, 17,30 ± 3,72 mg/km e 24,91 ± 2,71 mg/km para o combustível GNV; 3,80 ± 1,60 mg/km, 11,46 ± 1,04 mg/km e 5,47 ± 0,44 mg/km para o combustível EHC; e 3,26 ± 0,51 mg/km, 9,51 ± 1,32 mg/km e 15,82 ± 2,29 mg/km para o combustível gasool 22. Conclusão - De forma geral a emissão média de amônia medida antes do catalisador foi menor do que a medição efetuada após o catalisador para todos os combustíveis. Não foi detectada diferença significativa entre os valores de emissão de amônia feitos com dois teores diferentes de concentração de enxofre no gasool 22. Em linhas gerais a emissão de amônia mostrou-se dependente da forma de condução do veículo, apresentando valores superiores de emissão em relação ao ciclo de condução urbana (FTP-75), quando o veículo foi ensaiado seguindo os ciclos de condução NYCC e US- 06. Em princípio a emissão veicular de amônia pode ser importante na formação de material particulado fino em ambiente urbano, no qual é provável que as fontes tradicionais de emissão de amônia, como as atividades agrícolas, não sejam significativas.

Introduction - Ammonia (NH3) is an air pollutant whose emission is partly caused by human activities. Energy generation by burning fuels is one of those activities. In this area, the transportation sector has in on-road motor vehicles the major source of pollutant emissions. In addition to directly affect the human health, ammonia participates in atmospheric reactions that generate, as secondary pollutant, fine particulate matter. Objective - Verify in a vehicle with spark-ignition engine (Otto cycle), the values of ammonia emissions using the fuels gasohol 22, hydrous ethanol fuel (EHC) and compressed natural gas (CNG), with and without the presence of catalytic element (catalyst). Methods - The vehicle was tested on chassis dynamometer, following driving cycle and sampling of pollutants prescribed by ABNT NBR 6601 standard, for measuring exhaust emissions, and by ABNT NBR 7024, for measuring autonomy; and following the congestion (NYCC) and aggressive (US-06) driving cycles, adopted by the Environmental Protection Agency of USA (USEPA). In addition to the methods of gas analysis prescribed in these standards, the FTIR (Fourier Transform InfraRed) method was used for the measurement of NH3 and N2O. Results - Ammonia emissions were: average 1.06 ± 0.03 mg/km, 1.34 ± 0.42 mg/km and 1.22 ± 0.59 mg/km before the catalyst; and 4.16 ± 0.65 mg/km, 3.80 ± 1.60 mg/km and 3.88 ± 0.06 mg/km in measurements after the catalyst, respectively for the CNG, gasohol 22 and EHC fuels. Average values of ammonia emissions from tests with the use of gasohol 22 with sulfur content of 50 ppm and 350 ppm were respectively 3.26 ± 0.51 mg/km and 3.88 ± 0.06 mg/km. The average values of ammonia emissions for the FTP-75, NYCC and US-06 cycles, respectively, were: 4.16 ± 0.65 mg/km, 17.30 ± 3.72 mg/km and 24.91 ± 2.71 mg/km for the CNG fuel; 3.80 ± 1.60 mg/km, 11.46 ± 1.04 mg/km and 5.47 ± 0.44 mg/km for EHC fuel; and 3.26 ± 0.51 mg/km, 9.51 ± 1.32 mg/km and 15.82 ± 2.29 mg/km for the gasohol 22 fuel. Conclusion - In general, the average ammonia emissions measured before the catalyst was lower than the measurements made after the catalyst, for all fuels. There was no significant difference between the emission of ammonia made with two different levels of sulfur concentration in gasohol 22. Broadly the ammonia emission was dependent on the manner of driving of the vehicle, with higher emission values, compared to the urban driving cycle (FTP-75), when the vehicle was tested following the driving cycles NYCC and US-06. In principle vehicular emission of ammonia may be important in the formation of fine particulate matter in an urban environment in which it is likely that traditional sources of ammonia emissions, such as agricultural activities, are not significant.

Prevalência de halitose em pacientes com periodontite crônica ou gengivite / Halitosis in patients with chronic periodontitis or gingivitis

Estima-se que 90% da população possui alguma forma de doença periodontal e que a halitose afeta cerca de 50% dessa. Apesar de evidências sugerirem a correlação entre halitose e doença periodontal, são escassos os estudos que confirmam a prevalência da halitose nesses pacientes. Soma-se a isso o fato de haver variações e divergências entre os trabalhos existentes. O objetivo desta pesquisa foi comparar a prevalência da halitose em pacientes com periodontite crônica e em pacientes com gengivite. Foram avaliados 51 pacientes com periodontite crônica (grupo 1) e 42 pacientes com gengivite associada a placa sem fatores de retenção (grupo 2). Os níveis intraorais de compostos sulfurados voláteis (CSV) foram medidos pelo monitor de sulfetos (Halímeter). Também foram avaliados o índice de placa (IP), a profundidade de sondagem (PS) e o nível de inserção clínica (NIC). Os resultados evidenciaram que houve diferença estatisticamente significativa entre os grupos 1 e 2 para os níveis do hálito e os demais parâmetros clínicos mensurados (p < 0,0001). Através da análise da matriz de correlação linear também foi constatada correlação positiva moderada significativa entre o hálito e IP (p=0,03), e entre hálito e PS (p=0,03). Concluiu-se que a doença periodontal contribuiu efetivamente para a ocorrência de halitose, e que o tipo e a severidade da doença interferiram na sua magnitude e expressão clínica.

Beneficial Effects of Lactobacillus casei ATCC 334 on Halitosis Induced by Periodontopathogens

Halitosis is caused by consumption of certain foods or drinks and production of volatile sulfur compounds (VSCs) by periodontopathogens. VSCs-related halitosis is not easily removed using mechanical or chemical therapies such as dental floss, plaque control and mouth rinse. Lactobacillus are known to be probiotics and stimulate immune systems of human. Furthermore, L. casei ATCC 334 and L. rhamnosus GG have an effect on protection of dental caries in vitro studies. The aim of this study was to investigate effect of Lactobacillus on halitosis by Fusobacterium nucleatum- and Porphyromonas gingivalis- producing VSCs and to analyze inhibitory mechanism. The periodontopathogens were cultivated in the presence or the absence Lactobacillus, and the level of VSCs was measured by gas chromatograph. For analysis of inhibitory mechanisms, the susceptibility assay of the spent culture medium of Lactobacillus against F. nucleatum and P. gingivalis was investigated. Also, the spent culture medium of Lactobacillus and periodontopathogens were mixed, and the emission of VSCs from the spent culture medium was measured by gas chromatograph. L. casei and L. rhamnosus significantly reduced production of VSCs. L. casei and L. rhamnosus exhibited strong antibacterial activity against F. nucleatum and P. gingivalis. The spent culture medium of L. casei inhibited to emit gaseous hydrogen sulfide, methyl mercaptan and dimethyl sulfide from the spent culture medium of periodontopathogens. However, the spent medium of L. rhamnosus repressed only dimethyl sulfide. L. casei ATCC 334 may improve halitosis by growth inhibition of periodontopathogens and reduction of VSCs emission.

Effects of cetylpyridinium chloride buccal tablets on halitosis induced by oral conditions / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of cetylpyridinium chloride buccal tablets on halitosis induced by oral conditions.</p><p><b>METHODS</b>With Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum as the testing bacteria, the minimal inhibitory concentration (MIC) of cetylpyridinium chloride buccal tablets was determined using minute amount serial dilution test. The production of volatile sulfur compounds (VSCs) was measured using sulfide detector halimeter in the anaerobic bacteria culture at 4 and 8 h after addition of the tablets. The effect of the tablets in suppressing odor production by mouth-borne halitosis bacteria was assessed using cysteine challenge test in healthy volunteers, and the effectiveness was evaluated by measuring the reduction in VSCs production and the duration of the effect.</p><p><b>RESULTS</b>Cetylpyridinium chloride buccal tablets inhibited the growth of all the 3 bacteria. The tablets obviously inhibited VSCs production by the 3 bacteria with a effect similar to chlorhexidine. Compared with distilled water gargle, the buccal tablets significantly reduced cysteine-induced VSCs production level in the healthy volunteers (P<0.05), and the effect lasted for 230 min.</p><p><b>CONCLUSION</b>Cetylpyridinium chloride tablets can obviously suppress bacteria responsible for oral halitosis and produce good effects in the treatment of halitosis induced by oral conditions.</p>

Association Between Halitosis Diagnosed by a Questionnaire and Halimeter and Symptoms of Gastroesophageal Reflux Disease

BACKGROUND/AIMS: The relationship between halitosis and gastroesophageal reflux disease (GERD) remains controversial. The aim of this study was to investigate an association between subjective and objective halitosis and GERD. METHODS: The subjects were enrolled from participants who visited a health promotion center at Seoul National University Bundang Hospital. For diagnosis of halitosis, a questionnaire was requested, and volatile sulfur compounds (VSCs) were measured by Halimeter. Self-conscious halitosis was defined as halitosis perceived by himself or herself. Informed halitosis was defined as halitosis perceived by others. Objective halitosis was defined when mean VSCs values were > 100 parts per billion. GERD was defined based on a questionnaire and endoscopy, including erosive esophagitis and non-erosive reflux disease (NERD). RESULTS: A total of 54 subjects (male:female = 33:21) with mean age of 46.0 +/- 11.4 years were analyzed. The mean VSCs values were not significantly different between presence and absence of self-conscious halitosis (P = 0.322), but significantly different between presence and absence of informed halitosis (P = 0.021). Informed halitosis was associated with objective halitosis (P = 0.039). GERD, erosive esophagitis and NERD did not correlate with objective halitosis (P = 0.556, 0.206 and 0.902, respectively). In multivariable analysis, the relationship between objective halitosis and GERD symptoms including chest pain, heart burn, acid regurgitation, epigastric pain, hoarseness, globus sensation and coughing was not significant. Besides, GERD was not associated with self-conscious halitosis, informed halitosis and objective halitosis, respectively. CONCLUSIONS: GERD might not be associated with self-conscious, informed halitosis and objective halitosis indicated by Halimeter results. Informed halitosis could be correlated with objective halitosis determined by the Halimeter.

Sulfane sulfur deficiency in malignant cells, increasing the inhibiting action of acetone cyanohydrin in tumor growth

PURPOSE: To demonstrate the irreversible poisoning action of the acetone cyanohydrin (AC) in malignant cells. METHODS: Thirty male Swiss mice were inoculated with 1x10³ Ehrlich tumor (ET) cells. The mice were divided into three groups (n=10): CG (saline); ACG1 (1.864 mg/Kg of AC) and ACG2 (2.796 mg/Kg of AC), treated every 48 hours from day 3 until day 13. On day 15 the mice were euthanized and the number of viable cells in ascites was determined. In the meantime, ET cells were incubated with AC (0.5, 1.0, 2.0 μg/mL). Cell viability and percentage of growth inhibition (PGI) were checked after one, two, three, four, 18 and 24 hours. RESULTS: There was reduction in volume and number of viable cells in ACG1 and ACG2 compared to CG. In ACG1 one of the animals did not present ascites. In ACG2 two mice did not present ascites and in CG none of the mice present ascites. The action of AC was dose and time dependent and there was no significant difference among the three doses. CONCLUSION: The acetone cyanohydrin promoted reduction of the tumor and also prevented tumor development in 20% of the treated animals.

Relación entre los niveles de compuestos volátiles sulfurados con los niveles de RANKL y OPG en pacientes con periodontitis crónica moderada o severa: estudio transversal / Relationship between the levels of volatile sulfur compounds with the levels of RANKL and OPG in patients with moderate or severe periodontitis: A cross sectional study

Antecedentes: El efecto de los Compuestos Volátiles Sulfurados (CVS) sobre los tejidos periodontales, específicamente a nivel del eje RANKL/OPG, no ha sido dilucidado y en la actualidad existe escasa literatura al respecto publicada. Objetivo: Evaluar si los CVS medidos en la cavidad oral de pacientes con periodontitis crónica moderada a severa se relacionan con la expresión de RANKL y OPG a nivel de fluido gingival crevicular (FGC). Método: Se realizó un estudio transversal con 71 pacientes derivados de la Unidad de Diagnóstico de la Clínica Odontológica Docente Asistencial de la Universidad de los Andes. Posterior a la realización de un examen periodontal completo se tomaron muestra de los niveles de CVS de la boca de los pacientes mediante un monitor de sulfuros y muestras de FGC para evaluar los niveles de RANKL y OPG mediante test de ELISA. Los datos obtenidos fueron analizados mediante test de correlación de Spearman. Resultados: Al evaluar la correlación de los niveles de CVS con los niveles de RANKL, OPG y la razón RANKL/OPG, se observó un R de 0.098 con un p value = 0.41; -0.084 con un p value= 0.48 y 0.067 con un p value = 0.57 respectivamente. Conclusiones: El presente estudio no pudo demostrar si existe una relación entre los niveles de CVS con la expresión de RANKL y OPG en el FGC de pacientes con periodontitis crónica.

Background: The effect of the Volatile Sulfur Compounds (VSC) on the periodontal tissues, specifically at the RANKL/OPG level has not been elucidate and there is little literature published on this subject. Aim: To explore if the VSC levels measured in the oral cavity of patients with moderate or severe chronic periodontitis are correlated with the expression of RANKL and OPG at the gingival fluid level (GF). Method: A cross-sectional study was conducted with 71 patients referred by the Universidad de los Andes’s dentistry diagnosis department. After undergoing full-mouth periodontal exam, levels of CVS were recorded using a sulfur monitor and then GF was extracted to assess RANKL and OPG levels with ELISA. Data was analyzed with Spearman correlation test. Results: The correlation (R) between the VSC and the GF levels was 0.098 with a p value = 0.41; -0.084 with a p value = 0.48 y 0.067 with a p value = 0.57 respectively. Conclusions: This study could not demonstrate if there is a relation between the VSC levels and the expression of RANKL and OPG in the GF in patients with chronic periodontitis.