RESUMO
This study evaluated the impact of canal irrigation using surfactants associated to NaOCl on the percentage of voids of root canal filling through micro-computed tomographic (micro-CT) analysis. 27 mandibular mesial roots with Vertucci type II canal configuration with isthmus were selected and scanned in a micro-CT device. The specimens were assigned to three groups (n = 9), according to the irrigation solution during instrumentation: 2.5% NaOCl without additives (control), 2.5% NaOCl with 0.1% Benzalkonium Chloride and 2.5% NaOCl with 0.1% Tween 80. After obturation, the specimens were rescanned, and the percentage of voids were calculated. Data were analysed using one-way ANOVA with a significance level of 5%. The percentage of voids were similar among the groups (p > 0.05). None of the specimens showed completely voids-free areas. The addition of surfactants to NaOCl irrigation did not improve the quality of root canal filling of mandibular mesial root canals.
Assuntos
Irrigantes do Canal Radicular , Hipoclorito de Sódio , Tensoativos , Microtomografia por Raio-X , Hipoclorito de Sódio/farmacologia , Tensoativos/farmacologia , Irrigantes do Canal Radicular/farmacologia , Humanos , Microtomografia por Raio-X/métodos , Compostos de Benzalcônio/farmacologia , Obturação do Canal Radicular/métodos , Cavidade Pulpar/efeitos dos fármacos , Preparo de Canal Radicular/métodos , Irrigação Terapêutica/métodosRESUMO
This study aimed to evaluate in vitro the possible mechanisms underlying the estrogenic potential of benzalkonium chloride (BAC) as a disinfectant emerging contaminant. Effects of BAC at the environmentally-relevant concentrations on estrogen synthesis and estrogen receptor (ER) signaling were assessed using the H295R steroidogenesis assay and the MCF-7 proliferation assay, respectively. Results showed that exposure to BAC at concentrations of 1.0-1.5 mg/L for 48 h significantly increased estradiol production of H295R cells in a concentration-dependent manner. Transcription of steroidogenic genes 3ß-HSD2, 17ß-HSD1, 17ß-HSD4, and CYP19A were significantly enhanced by BAC. In ER-positive MCF-7 cells, exposure to 0.5-1.5 mg/L BAC for 48 h significantly promoted cell proliferation and increased the expressions of ERα and G-protein coupled estrogen receptor 1. Flow cytometry analysis showed that 0.5-1.5 mg/L BAC significantly decreased the percentage of cells in G0/G1 phase, increased the percentage in S phase, and BAC at concentrations of 1.0 and 1.5 mg/L increased the G2/M phase cells. Findings of the study suggested that BAC at environmentally-relevant concentrations might act as a xenoestrogen through its inhibitory effect on steroidogenesis and ER-mediated mechanism.
Assuntos
Compostos de Benzalcônio , Desinfetantes , Humanos , Compostos de Benzalcônio/farmacologia , Desinfetantes/farmacologia , Estradiol , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Proliferação de Células , Células MCF-7RESUMO
The growing number of Listeria monocytogenes strains displaying increased tolerance to sanitizers widely applied in the food industry is becoming a problem. The aims of this study were to evaluate the susceptibility of L. monocytogenes isolates from food and food industry environments to sanitizers (benzalkonium chloride, sodium hypochlorite, peracetic acid, and chlorhexidine) and heavy metals (cadmium chloride), as well as to investigate the presence of the main genes related to efflux pumps. All 82 isolates showed reduced susceptibility to benzalkonium chloride (MIC from 16 to 128 µg mL-1), sodium hypochlorite (MIC of ≥ 2048 µg mL-1), and peracetic acid (MIC from 512 to ≥ 2048 µg mL-1), while 22 isolates showed reduced susceptibility to cadmium chloride (MIC > 70 µg mL-1). Susceptibility to chlorhexidine was found (MIC from 2 to 16 µg mL-1). PCR-based analysis revealed that mdrl and lde genes were harbored by 14.6% (12/82) and 40.2% (33/82) of the isolates, respectively. This study demonstrates the presence of L. monocytogenes from food and food industry environments with reduced susceptibility to sanitizers commonly used in food processing environments, highlighting the importance of continuous monitoring of the tolerance profile of this microorganism to sanitizers, as well as the need for strict control of sanitation conditions in food industries.
Assuntos
Compostos de Benzalcônio , Listeria monocytogenes , Listeria monocytogenes/genética , Ácido Peracético , Hipoclorito de Sódio , Cloreto de Cádmio , Clorexidina , Manipulação de AlimentosRESUMO
Background: Topically administered 2% dorzolamide is among the most commonly used agents to lower IOP. As a complication of glaucoma, blind patients may develop corneal ulcers secondary to trauma. Nonetheless, in patients with a hypertensive or glaucomatous eye, in which the cornea has also been ulcerated, medical hypotensive therapy should not be discontinued. Therefore, the present study aimed to determine whether the instillation of a benzalkonium chloride (BAK)-preserved 2% dorzolamide alters corneal wound healing time and the levels of matrix metalloproteinases (MMP-9) in the tears of cats with experimentally induced corneal ulcers. Materials, Methods & Results: Sixteen cats (8/group) were randomly assigned to receive 40 µL of 2% dorzolamide (TG) or saline (CG) 3 times daily until corneal re-epithelialization. Experimental keratectomies were performed under general and topical anesthesia using an operating microscope. For this purpose, a millimitred trephine was calibrated and used to create a temporal paraxial corneal ulcer with a diameter of 6 mm and a depth of 200 µm. After corneal wounding, the ulcerated area, the healing time, blepharospasm, conjunctival hyperemia, and aqueous flare were compared between groups. Tears were collected at baseline and 24 and 48 h after keratectomy, and the total MMP-9 was quantified by ELISA. Data were assessed statistically using unpaired Student's t test, one-way, and two-way ANOVA followed by a Bonferroni post hoc test. Statistical significance was set at P < 0.05 for all analyses. The average time to achieve corneal wound healing did not differ between groups (P = 0.36) and was 65.50 ± 3.62 h in the CG and 71.00 ± 4.58 h in the TG. Twenty-four h after keratectomy, the ulcerated area in the CG was 3.34 mm2 larger than that observed in the TG (P = 0.04); the rest of the comparisons did not reach statistical significance at any time point between groups (P > 0.05). Higher blepharospasm scores were observed in cats of TG (P = 0.04). When compared with baseline of both groups, the levels of MMP-9 increased significantly at 24 and 48 h post-keratectomy (P < 0.001), but differences between groups were not observed at 24 and 48 h post-keratectomy (P > 0.05). Discussion: In cats, 9 mm axial corneal ulcers created by superficial debridement re-epithelize approximately 48 h postwounding. In the present study, re-epithelialization post keratectomy occurred within an average time of 68.25 h in most cats and in a delayed manner in one cat of the TG after 96 h. In the current study, the lesions in both groups healed without corneal scarring, pigmentation, or vascularization. Although BAC was present in all topical medications used in the present study, the authors attribute the higher scores of blepharospasm in the TG to the rheological characteristics and the pH of the dorzolamide ophthalmic solution. Indeed, the pH value of dorzolamide (5.58) may cause signs of irritation, as the tear film has an approximate pH of 7.6. Previous studies showed that ulcerated corneas presented significantly higher levels of MMP-9 in tears at the early stages (8 to 36 h) post-wounding. In the current study, the levels of this enzyme after wounding did not change significantly in the tears of cats treated with 2% dorzolamide when compared to the eyes in the control group. This study showed that the instillation of a BAC-preserved 2% dorzolamide ophthalmic solution did not impair the corneal wound healing time or the early expression of MMP-9 in the tears of cats with experimentally induced corneal ulcers. However, our results warrant further investigation in patients with ocular hypertension or glaucoma presenting concomitant naturally occurring corneal ulcers to certify our findings.
Assuntos
Animais , Gatos , Úlcera da Córnea/veterinária , Glaucoma/veterinária , Metaloproteinase 9 da Matriz/análise , Epitélio/fisiologia , Compostos de Benzalcônio/uso terapêutico , Inibidores da Anidrase CarbônicaRESUMO
The aim was to assess the physicochemical properties and the penetration into dentinal tubules of calcium hypochlorite solution [Ca(OCl)2], with or without surfactants. The surfactants benzalkonium chloride, cetrimide, Tween 80 and Triton X-100 were mixed at different concentrations with sodium hypochlorite solution (NaOCl), Ca(OCl)2 and distilled water (control). Once the critical micellar concentration (CMC) of the surfactants in Ca(OCl)2 and NaOCl was determined, pH, free chlorine, surface tension and free calcium ions were evaluated. The penetration into dentinal tubules of NaOCl and Ca(OCl)2, with or without benzalkonium chloride and Triton X-100 [surfactants that promoted the lowest surface tension of Ca(OCl)2], was assessed using human premolars stained with crystal violet. The statistical tests were one-way ANOVA and Tukey's post-test, Kruskal-Wallis and Dunn's post-test, two-way ANOVA and Bonferroni's post-test, and t-test; depending on the assay. The addition of surfactants reduced the surface tension of NaOCl and Ca(OCl)2, and did not alter the pH or the free available chlorine of either solution. The addition of all surfactants increased the availability of free calcium ions in Ca(OCl)2, especially benzalkonium chloride. Ca(OCl)2 exhibited lower penetration into dentinal tubules than NaOCl, and the addition of surfactants did not improve the penetration of Ca(OCl)2, but did increase the penetration of NaOCl. It can be concluded that the addition of surfactants to Ca(OCl)2 did not increase the penetration into dentinal tubules, but it did promote lower surface tension, without changing the pH or free available chlorine values, and higher availability of free calcium ions in Ca(OCl)2.
Assuntos
Irrigantes do Canal Radicular , Hipoclorito de Sódio , Compostos de Benzalcônio , Cálcio , Compostos de Cálcio , Cloro , Humanos , Octoxinol , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Tensoativos/químicaRESUMO
BACKGROUND: Benzalkonium chloride (BAK), the most commonly used preservative in anti-glaucoma eye drops, inflicts damage to the ocular surface. A novel anti-glaucoma formulation that avoids the use of BAK has been developed. The aim of this study was to evaluate the cytotoxicity of this formulation and to compare it with an ophthalmic solution containing BAK. METHODS: Two different latanoprost eye drops were used: one ophthalmic solution (LSc) containing BAK 0.02% and one ophthalmic nanoemulsion (LNe) with a soft preservative (potassium sorbate 0.18%). Human epithelial conjunctival cells were incubated for 15, 30, and 60 min with either LSc or LNe. The cytotoxicity was determined by MTT assay. Cell death was measured by flow cytometry using annexin V-FITC and propidium iodide. RESULTS: The values of cell viability and proliferation obtained from cells exposed to LNe were between 80 and 90% relative to the control group, whereas values obtained from cells exposed to LSc were around 30% at all study times (p < 0.05 at 15 and 30 min; p < 0.01 at 60 min). The percentage of viable cells decreased significantly when cells were incubated with LSc compared with cells incubated with LNe at all the study times, while the percentage of cells in late apoptosis/necrosis increased significantly in cells exposed to LSc compared to LNe. CONCLUSIONS: The new latanoprost nanoemulsion is significantly less cytotoxic on human conjunctival cells than LSc. These results suggest that the new formulation might be gentler on the eye surface than currently available BAK-preserved latanoprost solutions.
Assuntos
Glaucoma , Prostaglandinas F Sintéticas , Anti-Hipertensivos/toxicidade , Compostos de Benzalcônio/metabolismo , Compostos de Benzalcônio/toxicidade , Cloprostenol/metabolismo , Túnica Conjuntiva/metabolismo , Glaucoma/metabolismo , Humanos , Latanoprosta/toxicidade , Soluções Oftálmicas/toxicidade , Conservantes Farmacêuticos/metabolismo , Conservantes Farmacêuticos/toxicidade , Prostaglandinas F Sintéticas/toxicidade , TravoprostRESUMO
Tissue-Mimicking Material (TMM) is defined on IEC International Standards and applied in assessing ultrasonic diagnostic and therapeutic equipment's basic safety and essential performance. One of the TMM that fits IEC standards specification has its recipe described at IEC 60601-2-37, and it is fabricated using glycerol (11.21 %), deionized water (82.95%), benzalkonium chloride (0.47 %), silicon carbide (0.53 %), aluminum oxide 0.3 µm (0.88%), aluminum oxide 3.0 µm (0.94 %), and agar (3.08 %). Glycerol is the component responsible for adjusting the TMM's speed of sound. Moreover, it is recommended to store TMM in a closed container immersed in a mixture of water (88.1 %)/glycerol (11.9 %) to prevent it from drying out and avoiding air contact. The literature points out TMM measurements underwater can alter the speed of sound property as TMM tends to lose glycerol. Herein, the authors proposed to assess the viability of measuring the TMM speed of sound in the water/glycerol maintenance solution. First, the authors characterized the maintenance solution's speed of sound for a temperature range of 20 °C to 45 °C. Then, the group velocity of a set of TMM was measured underwater and in the maintenance solution for the same temperature range. The respective group velocity expanded uncertainty was calculated. The results indicate it is feasible to measure TMM in the maintenance solution, achieving group velocity values with no statistical difference from the ones measured underwater in the temperature range of 20 °C to 40 °C.
Assuntos
Materiais Biomiméticos , Imagens de Fantasmas/normas , Som , Terapia por Ultrassom/instrumentação , Ultrassonografia/instrumentação , Óxido de Alumínio , Compostos de Benzalcônio , Calibragem , Compostos Inorgânicos de Carbono , Segurança de Equipamentos , Glicerol , Compostos de Silício , Temperatura , ÁguaRESUMO
Biosecurity, cleaning and disinfection of swine and poultry facilities are fundamental for the reduction of pathogenic microorganisms of importance for public and animal health. The objective of this work was to compare the levels of active ingredient described on the label and the real levels detected in high-performance liquid chromatography (HPLC) of two disinfectants., then evaluate the antimicrobial activity since, following the Germicidal Sanitizing Action and Disinfectant Detergent (Official Method AOAC 960.09) in four different dilutions with the presence of 3% organic matter during 15 min of contact, against Salmonella Heidelberg and Salmonella Typhimurium (ST). The product "A" presents active levels of agreement according to the label. The content of quantified assets for product "B" was lower than that recorded on the label. The disinfectant "A" was effective in microbiological evaluation while the disinfectant "B" had microbiocidal activity compromised by the deficit of assets.
Assuntos
Salmonella , Salmonella typhimurium , Compostos de Benzalcônio/administração & dosagem , Desinfecção/métodos , Glutaral/administração & dosagem , Desinfetantes/análise , Cromatografia Líquida de Alta PressãoRESUMO
Purpose: The aims of this work were a) to describe the histology of the lacrimal gland (LG) and cornea induced by an adenovirus (Ad) vector encoding the human erythropoietin (Epo) gene delivered to the LG and b) to evaluate the therapeutic potential of this strategy to prevent benzalkonium chloride (BAK) corneal toxicity.Methods: Structure and function of male Wistar rats LG were compared in the groups: 1) naïve control and 2) Ad-hEpo in the right LG (RLG). The protective response against BAK eye drops was compared among the groups 1) naïve control, 2) BAK in the right eye, 3) Ad-hEpo RLG + BAK and 4) Ad-hEpo in the right salivary gland (RSG)+BAK. Ad-hEpo groups received an injection of AdLTR2EF1a-hEPO (25 ul, 1010 particles/ml) in the right LG or SG (positive control). The BAK groups received 0.2% BAK in the right cornea twice a day. The tests applied after 7 days, included tear secretion, hEPO mRNA detection by qRT-PCR, LG and cornea histology, LG ELISA for cytokines and hematocrit.Results: hEPO mRNA was present in the Ad-hEpo RLG and RSG, but not kidney or liver samples (negative controls). TNF-α and IL-1ß increased in the LG exposed to Ad-hEpo compared to naïve control (p = .0115 and p = .0397, respectively). BAK reduced tear secretion, but this reduction was prevented by Ad-hEpo RLG+BAK and Ad-hEpo RSG+BAK (p = .017). The corneal epithelia were thinner in the BAK-treated groups independent of Ad-hEpo (p = .0009). Hematocrit increased only in the Ad-hEpo RSG group (p = .01).Conclusions: Ad-hEpo infection of rat LG and SG induces local, but only the SG infection induced systemic changes in rats. Importantly, Ad-hEpo attenuated the BAK-mediated toxic reduction in tear flow. Future studies must consider viral vector tissue tropism, biodistribution and effective therapeutic gene products for ocular surface diseases.
Assuntos
Adenoviridae/genética , Síndromes do Olho Seco/terapia , Eritropoetina/genética , Terapia Genética/métodos , Aparelho Lacrimal/diagnóstico por imagem , Animais , Compostos de Benzalcônio/toxicidade , Modelos Animais de Doenças , Síndromes do Olho Seco/induzido quimicamente , Síndromes do Olho Seco/diagnóstico , Eritropoetina/metabolismo , Vetores Genéticos , Aparelho Lacrimal/efeitos dos fármacos , Aparelho Lacrimal/metabolismo , Masculino , Ratos , Ratos Wistar , Lágrimas/metabolismoRESUMO
Parameters such as type and concentration of the active compound, exposure time, application temperature, and organic load presence influence the antimicrobial action of sanitizers, although there is little data in the literature. Thus, this study aimed to evaluate the antifungal efficacy of different chemical sanitizers under different conditions according to the European Committee for Standardization (CEN). Aspergillus brasiliensis (ATCC 16404) was exposed to four compounds (benzalkonium chloride, iodine, peracetic acid, and sodium hypochlorite) at two different concentrations (minimum and maximum described on the product label), different exposure times (5, 10, and 15 min), temperatures (10, 20, 30, and 40 °C), and the presence or absence of an organic load. All parameters, including the type of sanitizer, influenced the antifungal efficacy of the tested compounds. Peracetic acid and benzalkonium chloride were the best antifungal sanitizers. The efficacy of peracetic acid increased as temperatures rose, although the opposite effect was observed for benzalkonium chloride. Sodium hypochlorite was ineffective under all tested conditions. In general, 5 min of sanitizer exposure is not enough and >10 min are necessary for effective fungal inactivation. The presence of organic load reduced sanitizer efficacy in most of the tested situations, and when comparing the efficacy of each compound in the presence and absence of an organic load, a difference of up to 1.5 log CFU was observed. The lowest concentration recommended on the sanitizer label is ineffective for 99.9% fungal inactivation, even at the highest exposure time (15 min) or under the best conditions of temperature and organic load absence. Knowledge of the influence exerted by these parameters contributes to successful hygiene since the person responsible for the sanitization process in the food facility can select and apply a certain compound in the most favorable conditions for maximum antifungal efficacy.