Exploring the Fluconazole-Resistance Modifying Activity and Potential Mechanism of Action of Fixed Oil from Caryocar coriaceum Wittm. (Caryocaraceae) against Candida Species.

The fixed oil from the inner mesocarp of Caryocar coriaceum Wittm. is used in the Chapada do Araripe region of Brazil for the treatment of genitourinary candidiasis. This study aimed to evaluate the chemical composition, antifungal activity, reduction of fungal virulence, and the preliminary toxicity of the fixed oil from the inner mesocarp of C. coriaceum tested against three Candida yeasts. The oil was characterized by gas chromatography (GC-MS and GC-FID). Antifungal activity was assessed using the serial microdilution method. Additionally, the potential of the oil as an enhancer of fluconazole action was tested at sub-inhibitory concentrations (MIC/8). The mechanism of action of C. coriaceum fixed oil was determined by evaluating the inhibition of morphological transition in Candida spp. The chemical composition of the fixed oil of C. coriaceum comprised both unsaturated and saturated fatty acids. Oleic (61 %) and palmitic (33 %) acids were the major constituents. Regarding its anti-Candida activity, the oil inhibited the growth of C. albicans (IC50 : 371 µg/mL) and C. tropicalis (IC50 : 830 µg/mL). Furthermore, the oil reversed the antifungal resistance of C. albicans and C. tropicalis, restoring the susceptibility to fluconazole and reducing their IC50 from 12.33 µg/mL and 362 µg/mL to 0.22 µg/mL and 13.93 µg/mL, respectively. The fixed oil of C. coriaceum completely inhibited the morphological transition of C. albicans and C. tropicalis at a concentration of 512 µg/mL, but exhibited limited low antifungal potential against C. krusei. The observed antifungal activity may be attributed to the overproduction of reactive oxygen species. Additionally, the oil showed no toxic effect on the Drosophila melanogaster in vivo model. The fixed oil from the inner mesocarp of C. coriaceum emerge as a strong candidate for the development of new pharmaceutical formulations to treat infections caused by Candida spp.

Brazilian National Network of Alternative Methods (RENAMA) 10th Anniversary: Meeting of the Associated Laboratories, May 2022.

The Brazilian National Network of Alternative Methods (RENAMA), which is linked to the Ministry of Science, Technology and Innovation, is currently comprised of 51 laboratories from CROs, academia, industry and government. RENAMA's aim is to develop and validate new approach methodologies (NAMs), as well as train researchers and disseminate information on their use - thus reducing Brazilian, and consequently Latin American, dependence on external technology. Moreover, it promotes the adoption of NAMs by educators and trained researchers, as well as the implementation of good laboratory practice (GLP) and the use of certified products. The RENAMA network started its activities in 2012, and was originally comprised of three central laboratories - the National Institute of Metrology, Quality and Technology (INMETRO); the National Institute of Quality Control in Health (INCQS); and the National Brazilian Biosciences Laboratory (LNBio) - and ten associated laboratories. In 2022, RENAMA celebrated its 10th anniversary, a milestone commemorated by the organisation of a meeting attended by different stakeholders, including the RENAMA-associated laboratories, academia, non-governmental organisations and industry. Ninety-six participants attended the meeting, held on 26 May 2022 in Balneário Camboriú, SC, Brazil, as part of the programme of the XXIII Brazilian Congress of Toxicology 2022. Significant moments of the RENAMA were remembered, and new goals and discussion themes were established. The lectures highlighted recent innovations in the toxicological sciences that have translated into the assessment of consumer product safety through the use of human-relevant NAMs instead of the use of existing animal-based approaches. The challenges and opportunities in accepting such practices for regulatory purposes were also presented and discussed.

Spatial-temporal distribution of maxillofacial injuries resulting from intimate partner violence against women.

BACKGROUND/AIM: Maxillofacial trauma resulting from intimate partner violence (IPV) represents an important oral health problem. In this sense, the aim of this study was to investigate the spatial-temporal distribution of maxillofacial trauma resulting from IPV against women, using a geostatistical approach. MATERIALS AND METHODS: An ecological study was carried out including the analysis of confirmed IPV cases against women treated at a Center for Forensic Medicine and Dentistry over a four-year observation period, as well as the evaluation of population data from the victims' places of residence extracted from the last demographic census of the Brazilian Institute of Geography and Statistics. Statistical analysis included: (i) finite mixture modeling to establish incidence trajectory patterns; (ii) Getis-Ord indicator (Gi*) for spatial autocorrelation; (iii) spatial regression analysis (p < .05). RESULTS: Two distinct trajectory patterns (TP1 and TP2) related to IPV incidence were identified using finite mixture modeling, suggesting spatial-temporal disparities at the regional level. In TP1, it was observed that IPV incidence was relatively low and remained stable over time, covering almost two-thirds (62.0%) of investigated spatial units. TP2 was characterized by higher IPV incidence with a tendency to increase in the last year, including more than one-third of neighborhoods (38.0%). Autocorrelation analysis showed a predominance of hot areas (hotspots) in the Eastern zone (p < .05) and in the Western zone (p < .05); and cold areas (coldspots) in the Northern zone (p < .05). In addition, statistically significant association was observed among neighborhoods with higher percentage of households with family householder without income and higher incidence of maxillofacial trauma resulting from IPV against women (ß = 5.305; SE = 1.741; p = .002). CONCLUSIONS: The findings indicate an association between higher IPV incidence against women, maxillofacial trauma, and socio-spatial vulnerability.

Caryocar coriaceum fruits as a potential alternative to combat fungal and bacterial infections: In vitro evaluation of methanolic extracts.

Caryocar coriaceum, commonly known as 'pequi', is a medicinal species used traditionally for the herbal treatment of infectious and parasitic diseases in the Brazilian Northeast region. In this study, we investigated whether the fruits of C. coriaceum have bioactive chemical constituents against etiological agents of infectious diseases. The methanolic extract of the internal mesocarp of the fruits of C. coriaceum (MECC) was chemically analyzed and evaluated for its antimicrobial and drug-enhancing activity against multidrug-resistant pathogenic bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus), and Candida spp. strains. The extract had flavones, flavonols, xanthones, catechins, and flavanones as major classes. A total of 11.26 mg GAE/g of phenolics, and 5.98 mg QE/g of flavonoids were found. No intrinsic antibacterial activity was observed; however, the extract was able to intensify the action of gentamicin and erythromycin against multi-resistant strains. The anti-Candida effect observed in this study was mainly due to the formation of reactive oxygen species. The extract was capable of causing damage to the plasmatic membrane of Candida tropicalis through pores formation. Our findings partially support the ethnopharmacological uses of the fruit pulp of C. coriaceum against infectious and parasitic diseases.

Is waist circumference associated with fear of falling in community-dwelling older adults? A cross-sectional study.

INTRODUCTION: Fear of falling (FOF) is a prevalent condition among older adults and several variables have been pointed out as risk factors. OBJECTIVES: To identify the cut-off point on waist circumference (WC), capable of discriminating between older adults with and without FOF, and to test the association between WC and FOF. METHODS: A cross-sectional observational study was carried out with older adults of both sexes from Balneário Arroio do Silva, Brazil. We used Receiver Operating Characteristic (ROC) curves to determine the cut-off point on WC and logistic regression adjusted for potential confounding variables to test the association. RESULTS: Older women with WC >93.5 cm [area under the curve: 0.61 (95%CI 0.53; 0.68)] had 3.30 (95%CI 1.53; 7.14) greater chances of having FOF compared with older women with WC ≤93.5 cm. WC was not able to discriminate FOF in older men. CONCLUSION: WC values >93.5 cm are associated with higher chances of FOF in older women.

Tridimensional assessment of the mandibular angle in patients with different skeletal patterns by cone-beam computed tomography scans: a retrospective study.

BACKGROUND: Since the muscles of chewing are involved in the region of the mandibular angle, important structures in surgical and orthodontic procedures, to study its morphological aspects and the possible influence of different patterns of skeletal development would be of interest. Thus, this study aimed to assess the influence of patient characteristics - such as sex, skeletal malocclusion (Class I, Class II, and Class III) and facial type (brachycephalic, mesocephalic, and dolichocephalic) - on the width, height, thickness, and volume of the mandibular angle, using cone-beam computed tomography (CBCT) scans. METHODS: CBCT scans were assessed - 144 men and 154 women, total of 298 - and classified according to skeletal patterns (skeletal malocclusions and facial types). Width, height, and thickness of the mandibular angle were measured using OnDemand 3D software. The volumetric measures of the mandibular angle were obtained using the ITK-SNAP software. Analysis of Variance (multiway ANOVA) with Tukey's post-hoc test compared the data, with a 5% significance level. RESULTS: Among the factors studied, sex significantly influenced all the analyzed variables (height, width, thickness, and volume of the mandibular angle) (p < 0.05); in general, male individuals presented higher values than females. In some cases, the skeletal malocclusion and facial type factors influenced only the width and height variables (p < 0.05); in general, the Class III and dolichocephalic individuals presented higher values in relation to the other types of skeletal malocclusions and facial types. CONCLUSIONS: Variations in the craniofacial growth pattern, considering the different skeletal malocclusions and facial types, had some influence in the width and height dimensions of the mandibular angle. Furthermore, sex influenced all the studied variables.

Hypericin, a medicinal compound from St. John's Wort, inhibits genotoxicity induced by mutagenic agents in V79 cells.

This study evaluated the cytotoxic, genotoxic, and the modulatory effects on DNA damage of hypericin in Chinese hamster lung fibroblasts (V79 cells). The hypericin is a natural polycyclic quinone, mainly extracted from St. John's Wort (Hypericum perforatum L.). Along with hyperforin, the hypericins are responsible for the antidepressant activity of St. John's Wort. Cytotoxicity was assessed by the XTT colorimetric assay and the nuclear division index (NDI). The genotoxic activity was studied by the micronucleus test at concentrations of 30, 60, 120, and 240 µg/mL. Mutagenic agents, methyl methanesulfonate (MMS, 44 µg/mL), doxorubicin (DXR, 0.5 µg/mL), and etoposide (VP16, 1 µg/mL) were used in combination with different concentrations of hypericin in order to evaluate the modulatory effect on DNA damage. Results showed that the hypericin was cytotoxic at concentrations above 156.2 µg/mL and genotoxic above 120 µg/mL. The hypericin significantly reduced DNA damage frequency induced by DXR, at concentrations of 30 and 60 µg/mL, and MMS at a concentration of 30 µg/mL, but was unable to reduce damage when combined with VP-16. These results demonstrate the non-photoactivated hypericin toxicological safety limits, its protective effect on DNA damage and provide a basis for future studies that may characterize better its chemopreventive mechanism.

Cognitive and behavioral factors associated to probable sarcopenia in community-dwelling older adults.

BACKGROUND: Sarcopenia has a high prevalence in older adults and is associated with chronic aggravations to health, so therefore it is important to identify older adults who are affected by sarcopenia in order to establish preventative strategies or early interventions. OBJECTIVE: To estimate the prevalence of probable sarcopenia and verify its association with cognitive impairment, fear of falling, depressive symptoms and health self-perception in community-dwelling older adults. METHODS: A cross-sectional study with simple random sampling including 306 older adults of both genders. The outcome variable was probable sarcopenia evaluated by the Five times sit-to-stand test (5XSST) considering probable sarcopenia when the measured time was > 15 seconds, following the recommendation of the European Working Group on Sarcopenia in Older People. The predictor variables were cognitive impairment, fear of falling, depressive symptoms and self-perception of health. Multivariate Logistic Regression was performed to verify associations between the variables. RESULTS: The prevalence of probable sarcopenia was 50.00%. The older adults had significantly higher chances of presenting probable sarcopenia when displaying cognitive impairment (OR 2.49; 95%CI 1.46-4.24), fear of falls (OR 4.23; 95%CI 2.51-7.12), depressive symptoms (OR 2.20; 95%CI 1.32-3.67), poor (OR 2.48; 95%CI 1.19-5.16) and fair self-perception of health (OR 2.11; 95%CI 1.22-3.63) when compared to those who did not have the same conditions. CONCLUSION: The prevalence of probable sarcopenia in this study was 50.00%, and was associated with the presence of depressive symptoms, cognitive impairment, fear of falls and negative self-perception of health.

Cannabidiol Treatment Improves Glucose Metabolism and Memory in Streptozotocin-Induced Alzheimer's Disease Rat Model: A Proof-of-Concept Study.

An early and persistent sign of Alzheimer's disease (AD) is glucose hypometabolism, which can be evaluated by positron emission tomography (PET) with 18F-2-fluoro-2-deoxy-D-glucose ([18F]FDG). Cannabidiol has demonstrated neuroprotective and anti-inflammatory properties but has not been evaluated by PET imaging in an AD model. Intracerebroventricular (icv) injection of streptozotocin (STZ) is a validated model for hypometabolism observed in AD. This proof-of-concept study evaluated the effect of cannabidiol treatment in the brain glucose metabolism of an icv-STZ AD model by PET imaging. Wistar male rats received 3 mg/kg of STZ and [18F]FDG PET images were acquired before and 7 days after STZ injection. Animals were treated with intraperitoneal cannabidiol (20 mg/kg-STZ-cannabidiol) or saline (STZ-saline) for one week. Novel object recognition was performed to evaluate short-term and long-term memory. [18F]FDG uptake in the whole brain was significantly lower in the STZ-saline group. Voxel-based analysis revealed a hypometabolism cluster close to the lateral ventricle, which was smaller in STZ-cannabidiol animals. The brain regions with more evident hypometabolism were the striatum, motor cortex, hippocampus, and thalamus, which was not observed in STZ-cannabidiol animals. In addition, STZ-cannabidiol animals revealed no changes in memory index. Thus, this study suggests that cannabidiol could be an early treatment for the neurodegenerative process observed in AD.

Dual phase statistical optimization of biological pre-treatment of sugarcane bagasse with Pycnoporus coccineus MScMS1 for polyhydroxyalkanoates production.

Biological pre-treatment is the removal of recalcitrant lignin from lignocellulose through the action of lignin degrading organisms and/or their ligninolytic enzymes system. Despite numerous environmental benefits, biological pre-treatment has been side-lined due to its prolonged periods of fermentation, ascribed to the slow growth rate of lignin degrading organisms. Thus, the present work adopted a dual phase statistical optimization approach for the biological pre-treatment of sugarcane bagasse, with Pycnoporus coccineus MScMS1, using Taguchi Orthogonal Array, in conjunction with Response Surface Methodology, to address this issue. Amplification of the organism's functioning resulted in an enhancement of sugar productivity and yield accompanied by a significant reduction in fermentation time. Optimized sugar concentration was approx. 18 g/L within 4 days of pre-treatment, with productivity of 4.5 g/(L.day). Substrate compositional analysis revealed significant (p < 0.05) reduction of lignin by 70% in the biologically pre-treated substrate, along with significantly (p < 0.05) higher quantities of water soluble components (35 ± 0.95 g) and cellulose content (33 ± 0.18 g), as compared to the untreated substrate. Appreciable levels of xylose, arabinose, glucose and galactose were detected in hydrolysates from biologically pre-treated bagasse. Furthermore, Bacillus megaterium Ti3, a potent polyhydroxyalkanoates (PHA) producer, was grown on these sugar-rich hydrolysates and generated 0.58 g/L PHA in 24 h of fermentation accompanied by 0.88 g/L dry cell weight and 65% PHA accumulation. These results were comparable with those from a glucose medium. Thus, the present study was successful in optimizing the biological pre-treatment of sugarcane bagasse and utilizing the resultant sugar-rich hydrolysates, as inexpensive and renewable raw materials, for PHA production.

How much time in sedentary behavior is associated with probable sarcopenia in older adults?

Sedentary activities, such as watching television and using the computer, are frequent conditions in older adults and can be associated with sarcopenia. The objectives of this study were: (a) to establish sedentary behavior (SB) cutoff values for screening probable sarcopenia in community-dwelling older adults and (b) to verify the association between SB and probable sarcopenia according to the established cutoff point. This was a cross-sectional study including 1,165 community residents in Florianopolis/SC. SB was assessed using the International Physical Activity Questionnaire. The outcome was probable sarcopenia (assessed by time ≥ 15 s in the Five times sit-to-stand test). The cut-off points found for SB were time > 120 min/day [AUC: 0.54 (95%CI: 0.51; 0.57)] watching TV or video/DVD and ≤ 20 min/day [AUC: 0.59 (95%CI: 0.56;0.62)] using computer/internet. Older adults with SB had 1.30 (95% CI: 1.01; 1.66) and 1.46 (95% CI: 1.08; 1.96) greater chances of having sarcopenia, respectively.

Influence of Asiatic acid on cell proliferation and DNA damage in vitro and in vivo systems.

Asiatic acid (AA) is a triterpene with promising pharmacological activity. In the present study, in vitro and in vivo assays were conducted to understand the effect of AA on cell proliferation and genomic instability. AA was cytotoxic to human tumor cell lines (M059J, HeLa, and MCF-7), with IC50 values ranging from 13.91 to 111.72 µM. In the case of M059J, AA exhibited selective cytotoxicity after 48 h of treatment (IC50 = 24 µM), decreasing the percentage of cells in the G0/G1 phase, increasing the percentage of cells in the S phase, and inducing apoptosis. A significant increase in chromosomal damage was observed in V79 cell cultures treated with AA (40 µM), revealing genotoxic activity. In contrast, low concentrations (5, 10, and 20 µM) of AA significantly reduced the frequencies of micronuclei induced by the mutagens doxorubicin (DXR), methyl methanesulfonate, and hydrogen peroxide. A reduction of DXR-induced intracellular free radicals was found in V79 cells treated with AA (10 µM). The antigenotoxic effect of AA (30 mg/kg) was also observed against DXR-induced chromosomal damage in Swiss mice. Significant reductions in p53 levels were verified in the liver tissue of these animals. Taken together, the data indicate that AA exerted antiproliferative activity in M059J tumor cells, which is probably related to the induction of DNA damage, leading to cell cycle arrest and apoptosis. Additionally, low concentrations of AA exhibited antigenotoxic effects and its antioxidant activity may be responsible, at least in part, for chemoprevention.

FGF, BMP, and RA signaling are sufficient for the induction of complete limb regeneration from non-regenerating wounds on Ambystoma mexicanum limbs.

Some organisms, such as the Mexican axolotl, have the capacity to regenerate complicated biological structures throughout their lives. Which molecular pathways are sufficient to induce a complete endogenous regenerative response in injured tissue is an important question that remains unanswered. Using a gain-of-function regeneration assay, known as the Accessory Limb Model (ALM), we and others have begun to identify the molecular underpinnings of the three essential requirements for limb regeneration; wounding, neurotrophic signaling, and the induction of pattern from cells that retain positional memory. We have previously shown that treatment of Mexican axolotls with exogenous retinoic acid (RA) is sufficient to induce the formation of complete limb structures from blastemas that were generated by deviating a nerve bundle into an anterior-located wound site on the limb. Here we show that these ectopic structures are capable of regenerating and inducing new pattern to form when grafted into new anterior-located wounds. We additionally found that the expression of Alx4 decreases, and Shh expression increases in these anterior located blastemas, but not in the mature anterior tissues, supporting the hypothesis that RA treatment posteriorizes blastema tissue. Based on these and previous observations, we used the ALM assay to test the hypothesis that a complete regenerative response can be generated by treating anterior-located superficial limb wounds with a specific combination of growth factors at defined developmental stages. Our data shows that limb wounds that are first treated with a combination of FGF-2, FGF-8, and BMP-2, followed by RA treatment of the resultant mid-bud stage blastema, will result in the generation of limbs with complete proximal/distal and anterior/posterior limb axes. Thus, the minimal signaling requirements from the nerve and a positional disparity are achieved with the application of this specific combination of signaling molecules.

In silico, in vitro and in vivo evaluation of natural Bignoniaceous naphthoquinones in comparison with atovaquone targeting the selection of potential antimalarial candidates.

The natural naphthoquinones lapachol, α- and ß-lapachone are found in Bignoniaceous Brazilian plant species of the Tabebuia genus (synonym Handroanthus) and are recognized for diverse bioactivities, including as antimalarial. The aim of the present work was to perform in silico, in vitro and in vivo studies to evaluating the antimalarial potential of these three naphthoquinones in comparison with atovaquone, a synthetic antimalarial. The ADMET properties of these compounds were predicted in silico by the preADMET program. The in vitro toxicity assays were experimentally determined in immortalized and tumoral cells from different organs. In vivo acute oral toxicity was also evaluated for lapachol. Several favorable pharmacokinetics data were predicted although, as expected, high cytotoxicity was experimentally determined for ß-lapachone. Lapachol was not cytotoxic or showed low cytotoxicity to all of the cells assayed (HepG2, A549, Neuro 2A, LLC-PK1, MRC-5), it was nontoxic in the acute oral test and disclosed the best parasite selectivity index in the in vitro assays against chloroquine resistant Plasmodium falciparum W2 strain. On the other hand, α- and ß-lapachone were more potent than lapachol in the antiplasmodial assays but with low parasite selectivity due to their cytotoxicity. The diversity of data here reported disclosed lapachol as a promising candidate to antimalarial drug development.

Use of chemically activated termite feces a low-cost adsorbent for the adsorption of norfloxacin from aqueous solution.

Antibiotics, as emerging contaminants, are of global concern due to the development of antibiotic resistant microorganisms. Current wastewater treatment technology cannot efficiently remove sewage antibiotics and therefore new low-cost technologies are needed. Adsorption is a widely used process for removal of substances, and the search for efficient, low-cost adsorbents is ongoing. In this work, termite feces treated with H2SO4 (FT/H2SO4) were used as a low-cost adsorbent for removal of norfloxacin (NOR) present in aqueous medium. Termite feces were treated with H2SO4 at a ratio of 1:1 for 24 h, at 100 °C. The parameters contact time, initial NOR concentration, medium pH and temperature were evaluated. The optimum adsorption pH was 8.0. The pseudo-second-order model was found to best represent the kinetics of NOR adsorption. The maximum adsorption capacity, calculated from the Sips isotherm model, was 104.4 mg/g at 55 °C. The positive values of ΔH0 (change in enthalpy) confirm the endothermic nature of the adsorption. The results show that FT/H2SO4 is an efficient adsorbent for removal of NOR present in aqueous medium. The adsorption capacity is higher than those reported in the literature for other low-cost adsorbents.

Levels of organochlorine pesticides in Amazon turtle (Podocnemis unifilis) in the Xingu River, Brazil.

Due to the toxicity and high environmental persistence of organochlorine pesticides in aquatic organisms, turtles have been studied as environment biomonitors. These animals are important sources of protein for the riverside and indigenous peoples of the Brazilian amazon. In the present study, organochlorine pesticide contamination was investigated in Podocnemis unifilis. Liver, muscle and fatty tissue samples were removed from 50 specimens collected from five sampling points located in the Xingu River basin. Fourteen organochlorine pesticides were analysed via gas chromatography with an electron capture detector (CG-ECD). Eight organochlorine pesticides were detected with average concentrations of ∑DDT, ∑Endossulfan and ∑HCH which were 26.17 ± 26.35, 14.38 ± 23.77 and 1.39 ± 8.46 ng g-1 in moisture content, respectively. DDT compounds were the most predominant, with a greater concentration of pp'-DDT in the liver and pp'-DDD in the muscle. Significant differences were noted between the types of tissues studied, and the concentration of OCPs varied between sampling sites.

Assessment of DDT and Metabolites in Soil and Sediment of Potentially Contaminated Areas of Belém, Amazon Region, Brazil.

The aim of this study was to evaluate the distribution of DDT and metabolites in surface soils and soil profiles from two areas containing deposits of obsolete pesticides in Belém, Amazon Region, Brazil. DDT and metabolites were extracted by microwave assisted extraction and analyzed by gas chromatography with electron capture detection. Concentrations of total DDT in surface soil samples ranged from 64.22 mg kg-1 in area 1 (A1) to 447.84 mg kg-1 in area 2 (A2). Lower levels were found in soil profiles than at the surface (6.21-21.17 mg kg-1 in A1 and 36.13-113.66 mg kg-1 in A2). pp'-DDT, pp'-DDE and pp'-DDD were detected in sediments at levels of 2.01, 0.96 and 0.35 mg kg-1, respectively. The ratio (DDE + DDD)/ΣDDT was low indicating the recent introduction of DDT to the environment in the two study areas, through the volatilization and atmospheric deposition of the obsolete pesticides.

Antimicrobial activity of Buchenavia tetraphylla against Candida albicans strains isolated from vaginal secretions.

CONTEXT: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action. OBJECTIVE: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed. MATERIALS AND METHODS: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007). RESULTS: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500 µg/mL for the BTHE; 156 to 1250 µg/mL for the BTCE; 625 to 1250 µg/mL for the BTME and 625 µg/mL to 2500 µg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC50 values of 981 and 3935 µg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages. DISCUSSION AND CONCLUSION: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.

A randomized placebo-blind study of the effect of low power laser on pain caused by irreversible pulpitis.

This randomized placebo-blind study aimed to evaluate the effect of laser phototherapy (LPT) on pain caused by symptomatic irreversible pulpitis (SIP). Sixty patients diagnosed with SIP were randomly assigned to treatment groups (n = 15): G1 (control), G2 (laser placebo-sham irradiation), G3 (laser irradiation at 780 nm, 40 mW, 4 J/cm2), and G4 (laser irradiation at 780 nm, 40 mW, 40 J/cm2). Spontaneous pain was recorded using a VAS score before (T0), immediately after (T1), and 15 min after treatment (T2). Local anesthetics failure during emergency endodontic treatment was also assessed. There was no pain difference in T1 and T2 between the experimental laser groups (G3 and G4) and the placebo group (G2). The 4-J/cm2 (G3) irradiation resulted in significant increase in the local anesthetics failure in lower jar teeth. This effect could be suggested as consequence of the LPT improvement in local circulation and vasodilatation that would result in the increase of local anesthetic agent absorption. The application of 780-nm diode laser irradiation, at 4 and 40 J/cm2, showed no effect in reducing the pain in SIP in comparison to the placebo group. The fluence of 4 J/cm2 showed a negative effect in local anesthetics, resulting in significant increase of complimentary local anesthesia during emergency endodontic treatment. This work provides evidence of the consequence of LPT application on teeth with symptomatic irreversible pulpitis. LPT should be avoided in teeth with pain due to irreversible pulpitis.