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1.
Phys Chem Chem Phys ; 26(11): 8613-8622, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38275280

RESUMO

In this work, we present a density functional theory benchmark on antioxidant-related properties for a series of six polyphenols that are well-known antioxidants: caffeic acid, cyanidin, ellagic acid, gallic acid, myricetin, and phloretin. Computations on the 24 O-H bond dissociation enthalpies (BDEs) and 6 ionization potentials (IPs) were performed using twenty-three exchange-correlation functionals combined with four different basis sets in the gas-phase, water, and methanol; calibration against the Domain-based Local Pair Natural Orbital CCSD(T) (DLPNO-CCSD(T)) approach was employed. Mean absolute deviation (MAD) as well as linear fitting results suggested the LC-PBE approach as the most suitable for O-H BDEs in the gas-phase. The LC-PBE, M06-2X, and M05-2X results presented the smallest MADs for O-H BDEs when compared to the reference, in water. The LC-PBE results had the smallest MADs for IPs in the gas-phase while M05-2X, M06-2X, LC-PBE, and LC-ωPBE exhibited the best results for MAD in water. We expect the outcomes from the present work will serve as general guidance for researchers working in the field.

2.
J Phys Chem A ; 128(14): 2727-2736, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38538553

RESUMO

In this work, properties related to antioxidant-potential mechanisms (such as the bond dissociation enthalpy, BDE, for the homolytic cleavage of the O-H bond and ionization energies, IEs) were determined for phenol, pyrocatechol, and gallic acid (GA). Both the protonated and deprotonated forms of GA were investigated. The Feller-Peterson-Dixon (FPD) composite method was employed with a variety of computational approaches, i.e., density functional theory, Möller-Plesset perturbation theory, and coupled-cluster-based methods, in combination with large correlation consistent basis sets with extrapolation to the complete basis set limit and consideration of core electron correlation effects. FPD results were compared to experimental and computational data available in the literature, presenting good agreement. For example, the FPD BDE (298 K) obtained for phenol, which was based on valence-correlated MP2/CBS calculations with contributions from correlating all electrons, was determined to be 87.56 kcal/mol, a value that is 0.42 kcal/mol lower than the result obtained in the most recent experiments, 87.98 ± 0.62. Calibration against coupled-cluster calculations was also carried out for phenol. We expect that the outcomes gathered here may help in establishing a general protocol for computational chemists that are interested in determining antioxidant-related properties for phenolic compounds with considerable accuracy as well as to motivate future IE measurements (particularly for GA) to be accomplished in the near future.

3.
Int Endod J ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126293

RESUMO

AIM: Natural bioactive products have been tested as alternative antimicrobial agents. This study evaluated the effect of Punica granatum extract (PGE) on oral multispecies biofilms. METHODOLOGY: Lyophilized extracts from pomegranate peel were prepared, and the punicalagin content was assessed by ultra-performance liquid chromatography (UPLC). Oral multispecies biofilms from 2 donors were grown on four collagen-coated hydroxyapatite discs. After incubation for 7 days or 3 weeks, the biofilms were exposed to water (control), 2% CHX, 10% PGE, 20% PGE or 30% PGE for 3 min. The proportions of dead bacteria were assessed by the live/dead staining and confocal microscopy. After the analysis, the best PGE concentration (30%) was combined with CHX. The experimental phases were repeated using water, 2% CHX, 30% PGE and 30% PGE + 2% CHX. Five random areas of the biofilm on each disc were scanned, resulting in 20 scanned areas for each group. RESULTS: Regarding the biofilm volume, no differences were found amongst solutions (p = .111). The PGE solution killed bacteria effectively in 1-week, 2-week and 3-week-old-plaque biofilms, ranging from 37 to 55.3%, depending on the PGE concentration. The 30% PGE (a) (p = .0009) had greater antibiofilm effectiveness than 2% CHX (b), which killed bacteria in the 25.2 to 48.7% range. The 10% and 20% PGE had intermediate values (ab), without significant differences from 30% PGE (p = 1.002). Water (c) had the lowest proportion of dead bacteria (p < .00001) in a range of 5 to 6.7% and lower effectiveness in killing bacteria (p < .05). The PGE alone or mixed with 2% CHX had greater anti-biofilm effectiveness than CHX (p < .05). The old plaque biofilms were more resistant than the 7-day-old plaque (p < .05). CONCLUSIONS: The 30% PGE (alone or combined with CHX) exhibited a greater antibiofilm effect on oral multispecies biofilms grown on hydroxyapatite discs than 2% CHX.

4.
Lasers Med Sci ; 39(1): 184, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39020076

RESUMO

PURPOSE: This study aimed to investigate the efficiency of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm in the oral cavity using the photosensitizer chloroaluminum phthalocyanine encapsulated in chitosan nanoparticles (ClAlPc/Ch) at three preirradiation times. METHODS: Biofilms of Streptococcus mutans strains (ATCC 25,175) were cultivated on bovine tooth blocks and exposed to a 10% sucrose solution three times a day for 1 min over three consecutive days. The samples were randomly distributed into five treatment groups (n = 5): (I) aPDT with ClAlPc/Ch with a preirradiation time of 5 min (F5), (II) aPDT with ClAlPc/Ch with a preirradiation time of 15 min (F15), (III) aPDT with ClAlPc/Ch with a preirradiation time of 30 min (F30), (IV) 0.12% chlorhexidine digluconate (CHX), and (V) 0.9% saline solution (NaCl). After treatment, the S. mutans biofilms formed on each specimen were collected to determine the number of viable bacteria (colony-forming units (CFU)/mL). Data were analyzed for normality using the Shapiro-Wilk test and the analysis of variance (ANOVA) and Tukey HSD tests to analyze the number of viable bacteria (α = 0.05). RESULTS: The one-way ANOVA showed a difference between the groups (p = 0.0003), and the Tukey HSD posttest showed that CHX had the highest microbial reduction of S. mutans, not statistically different from the F5 and F15 groups, whereas the NaCl group had the lowest microbial reduction statistically similar to the F30 group. CONCLUSION: The results demonstrate that aPDT mediated by ClAlPc/Ch when used at preirradiation times of 5-15 min can be an effective approach in controlling cariogenic biofilm of S. mutans, being an alternative to 0.12% CHX.


Assuntos
Biofilmes , Quitosana , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Streptococcus mutans , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Streptococcus mutans/fisiologia , Fotoquimioterapia/métodos , Quitosana/farmacologia , Quitosana/química , Nanopartículas/química , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Animais , Bovinos , Fármacos Fotossensibilizantes/farmacologia , Técnicas In Vitro , Indóis/farmacologia , Boca/microbiologia , Clorexidina/farmacologia , Clorexidina/análogos & derivados , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Compostos Organometálicos
5.
Clin Oral Investig ; 28(5): 253, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630376

RESUMO

OBJECTIVES: To evaluate the longevity of resin composite restorations placed in posterior teeth by dental students, using data from electronic records from 2008 to 2019. MATERIALS AND METHODS: Demographic (gender and age) and clinical variables (dental group, position in dental arch, and the number of restored surfaces) were evaluated. The 5-year follow-up was assessed according to the day the restoration was placed. Kaplan-Meier curves were generated to calculate the annual failure rate. Data were analyzed by Chi-Square, Kruskal-Wallis, and Mann-Whitney tests (α = 0.05). RESULTS: In total, 3.883 records relative to return periodicity were analyzed. The final sample consisted of 900 restorations from 479 patients. The majority were females, aged between 31 and 60. In total, 256 failures were reported (success rate = 78%), showing an annual failure rate of 2.05%. The main reasons for failures were restoration replacement (55.5%), endodontics (21.9%), prosthetics (14.5%) and extraction (8.2%). There was a higher risk of failure in restorations involving three or more surfaces (p = 0.000) and in patients over 60 years (p < 0.001). In females (p = 0.030), molars (p = 0.044), and maxillary teeth (p = 0.038) failed in a shorter time. CONCLUSIONS: Resin composite restorations placed in permanent posterior teeth by dental students had high survival rates. The main reason for failure was the replacement of restorations. The age group and the number of restored surfaces significantly affected the success of the restorations. CLINICAL RELEVANCE: The electronic health records over 12 years showed that 78% of the resin restorations in posterior teeth placed by dental students were successful for a minimum of five years.


Assuntos
Dente Molar , Estudantes de Odontologia , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Resinas Compostas , Assistência Odontológica
6.
Odontology ; 112(3): 773-781, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38305943

RESUMO

This study analyzed and compared the physicochemical and mechanical properties of preheated resin composite with light-cured resin cement for luting indirect restorations. 210 specimens of resin cement/resin composite were prepared according to preheating treatment heated (Htd) or not (NHtd). Light-cured resin cement (Variolink Veneer, Ivoclar), and resin composite (Microhybrid-Z100, 3 M; Nanohybrid-Empress direct, Ivoclar; and Bulk fill-Filtek One, 3 M) were used (n = 10). Resin cement specimens were not preheated. The response variables were (n = 10): film thickness, microhardness, liquid sorption and solubility. Data were analyzed by 2-way ANOVA and Tukey HSD post-test (α = 0.05). Bulk fill NHtd resin had the highest film thickness values (p < 0.001). Microhybrid and nanohybrid Htd resins had the smallest thicknesses and did not differ from the cement (p > 0.05). The highest microhardness values were found for Bulk fill NHtd and Bulk fill Htd resins. The nanohybrid and microhybrid Htd resins showed the lowest microhardness values, with no difference in cement (p > 0.05). For liquid sorption, there was no significant difference between the groups (p = 0.1941). The microhybrid Htd resin showed higher solubility values than the other materials (p = 0.0023), but it did not differ statistically from resin cement (p > 0.05). Preheating composite resins reduced the film thickness. After heating, nanohybrid and Bulk fill resins retained stable microhardness, sorption, and solubility values.


Assuntos
Cerâmica , Resinas Compostas , Teste de Materiais , Solubilidade , Resinas Compostas/química , Cerâmica/química , Cimentos de Resina/química , Propriedades de Superfície , Dureza , Temperatura Alta , Fenômenos Químicos
7.
J Esthet Restor Dent ; 36(6): 941-950, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38475977

RESUMO

OBJECTIVES: To investigate the effect of cumulative doses of radiation on the pushout bond strength (BS) of a universal resin cement used in the self-etch (SE) and self-adhesive (SA) modes to the intraradicular dentin. MATERIALS AND METHODS: Forty-eight human teeth were distributed into three groups (n = 16) according to the radiation therapy dose (RT): NoRT (no-radiotherapy), 70RT (70 Gy), and 70 + 70RT (70 Gy + 70 Gy). The teeth were redistributed into two subgroups (n = 8), according to the adhesive mode: SE (NoRT-SE, 70RT-SE, and 70 + 70RT-SE) and SA (NoRT-SA, 70RT-SA, and 70 + 70RT-SA). Data were statistically compared after BS test (ANOVA, Tukey's post hoc test, and Fisher's exact test). RESULTS: In the SA mode, BS was significantly higher in nonirradiated teeth compared with 70RT and 70 + 70RT (p < 0.0001). There were no significant differences between SE and SA modes in nonirradiated teeth (p = 0.14). In the 70RT group, SE mode increased BS compared with SA mode (p < 0.0001). Most specimens had adhesive and mixed failures in SA and SE modes, respectively. CONCLUSIONS: The universal resin cement in the SE mode had greater BS to the irradiated dentin. When teeth were re-irradiated, the universal resin cement had similar performance in terms of BS, regardless of the adhesive approach. CLINICAL SIGNIFICANCE: There is no research establishing a correlation between radiotherapy and its impact on the BS of a universal resin cement used in SE and SA modes to intraradicular dentin.


Assuntos
Colagem Dentária , Cimentos de Resina , Humanos , Cimentos de Resina/química , Colagem Dentária/métodos , Dentina , Análise do Estresse Dentário , Teste de Materiais , Adesivos Dentinários/química , Condicionamento Ácido do Dente
8.
Prev Med ; 175: 107679, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37625652

RESUMO

The debate over urban-rural health disparities in Latin American countries is disputed, and this relationship may not be as straightforward as initially thought. In this study, we investigate whether individual-level self-rated health (SRH) varies across urban and rural populations in the country and how sociodemographic attributes are associated with such differences. We relied on data from the Brazilian National Health Survey (n = 78,806), a nationwide household-based survey conducted in 2019 that is representative of Brazil, geopolitical macro-regions, states, and 27 state capitals. Logistic regression models were used to test for differences in SRH between urban and rural inhabitants. The findings suggest that Brazilian adults living in rural areas are at a higher risk of perceiving their health as poor than their urban counterparts. The urban-rural health disparities are significant and influenced by sociodemographic attributes, highlighting the importance of developing public health interventions to improve health outcomes in these populations.

9.
Lasers Med Sci ; 38(1): 255, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932490

RESUMO

PURPOSE: This systematic review provides an overview of the main chemical and morphological alterations generated on dentin by different high-power lasers' irradiation. METHODS: The review was registered in PROSPERO (CRD42023394164) and PRISMA guidelines were followed. The search strategy was conducted on MEDLINE (PubMed), Embase (Elsevier), and Web of Science (Clarivate) databases. The eligibility criteria were established according to the PICOS strategy, focusing on in vitro and ex vivo studies that assessed the chemical and morphological changes in dentin using five high-power lasers: Nd:YAG (1064 nm), Er:YAG (2940 nm), Er, Cr:YSGG (2780 nm), diode (980 nm), and CO2 (10,600 nm). Publication range was from 2010 to 2022. Data was summarized in tables and risk of bias was assessed by QUIN tool. RESULTS: The search resulted in 2255 matches and 57 studies composed the sample. The methods most used to assess the outcomes were scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and Raman. The studies presented "medium" and "low" risk of bias. The laser prevalently identified was the Er:YAG laser, associated with dentin ablation, absence of smear layer, and exposed tubules. The Nd:YAG laser generated vitreous surface and thermal damage, such as carbonization and cracks. The other lasers caused an irregular surface and no adverse thermal effects. Regarding the chemical structure, only the Er,Cr:YSGG laser caused collagen matrix reduction. The effects found were more intense with higher dosimetry. CONCLUSION: Evidence available indicates that the irradiation of dentin with high-power lasers are related to morphological outcomes favorable to adhesive restorative procedures, with minimal changes in collagen matrix and mineral content. However, those observations should be carried carefully by clinicians and more clinical trials regarding the association of high-power laser irradiation and restorative procedure longevity are needed.


Assuntos
Dentina , Lasers de Estado Sólido , Dentina/efeitos da radiação , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Colágeno
10.
Lasers Med Sci ; 38(1): 208, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37697177

RESUMO

This study evaluated the effect of chitosan on dentin treatment after selective removal of caries lesions with Er:YAG laser in reducing Streptococcus mutans, as well as its effect on the performed restorations. The sample consisted of children (aged 7 to 9 years) with active carious lesions and dentin cavitation located on the occlusal surface of deciduous molars. Eighty teeth were randomly distributed into 4 groups according to the caries removal method: Er:YAG laser (250 mJ/4 Hz) or bur and dentin surface treatment: 2.5% chitosan solution or distilled water. The bacterial load of caries-affected dentin was quantified by counting CFU/mg (n = 10). The teeth were restored and evaluated at 7 days, 6 months, and 12 months using modified USPHS criteria (n = 20). Microbiological data was analyzed by Mann-Whitney and clinical analyses were done using Kruskal-Wallis and Dunn test (α = 0.05). The results showed that the Er:YAG laser significantly reduced the amount of Streptococcus mutans (p = 0.0068). After dentin treatment with chitosan, there was a significant reduction in the amount of Streptococcus mutans for both removal methods (p = 0.0424). For the retention and secondary caries criteria, no significant differences were observed along the evaluated time (p > 0.05). The laser-treated group was rated "bravo" for discoloration (p = 0.0089) and marginal adaptation (p = 0.0003) after 6 and 12 months compared to baseline. The Er:YAG laser reduced the amount of Streptococcus mutans and the chitosan showed an additional antibacterial effect. After 1 year, the Er:YAG laser-prepared teeth, regardless of the dentin treatment, showed greater discoloration and marginal adaptation of the restorations.


Assuntos
Quitosana , Cárie Dentária , Lasers de Estado Sólido , Estados Unidos , Criança , Humanos , Lasers de Estado Sólido/uso terapêutico , Quitosana/uso terapêutico , Suscetibilidade à Cárie Dentária , Antibacterianos , Cárie Dentária/radioterapia , Streptococcus mutans , Dentina
11.
Lasers Med Sci ; 38(1): 77, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36823417

RESUMO

The purpose of this study is to assess the laser effect in root canal disinfection and periapical healing of endodontically treated teeth from patients with asymptomatic apical periodontitis. This study was performed as a randomized clinical trial. Thirty patients were selected according to the inclusion/exclusion criteria. Fifteen patients received the root canal retreatment (RCR) combined with 980-nm diode laser irradiation (LI). The canals were irrigated with saline solution and gently dried with paper points, keeping the dentin partially moist. The irradiation was performed using a 320-µm-diameter fiber in helicoidal movements (pulsed mode, power output of 1.5 W, 100 Hz for 20 s). The other 15 patients received the RCR with placebo irradiation (PI). Microbiological samples were taken in three periods: S1, after the filling material removal (baseline); S2, after laser or placebo irradiation (LI or PI); and S3, after the RCR followed by laser or placebo. The samples were submitted to the total microbial and E. faecalis counting. The periapical radiographic healing was analyzed after 3, 6, 9, and 12 months. Microbiological data (CFU/mg) were analyzed by ANOVA and Tukey's test (P < 0.05), and the repair by Mann-Whitney test (P < 0.05). In S2, the laser provided 42.44% microbial reduction and 53.14% of E. faecalis, different from the placebo that had no reduction, and 4.85% for Enterococcus (P < 0.05). In S3, the bacterial counts decreased without differences between groups. No differences in healing were found at 3 months. However, diode laser facilitated the repair from 3- to 12-month follow-up (P < 0.05) and had 45% more healed cases than placebo. Diode laser provided an antimicrobial effect before the biomechanical preparation but was not synergistic in RCR. It improved the periapical healing during follow-up.


Assuntos
Cavidade Pulpar , Lasers Semicondutores , Humanos , Lasers Semicondutores/uso terapêutico , Seguimentos , Tratamento do Canal Radicular , Enterococcus faecalis , Preparo de Canal Radicular , Irrigantes do Canal Radicular/farmacologia
12.
Plant Mol Biol ; 110(3): 253-268, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35798935

RESUMO

KEY MESSAGE: SlBBX28 is a positive regulator of auxin metabolism and signaling, affecting plant growth and flower number in tomato B-box domain-containing proteins (BBXs) comprise a family of transcription factors that regulate several processes, such as photomorphogenesis, flowering, and stress responses. For this reason, attention is being directed toward the functional characterization of these proteins, although knowledge in species other than Arabidopsis thaliana remains scarce. Particularly in the tomato, Solanum lycopersicum, only three out of 31 SlBBX proteins have been functionally characterized to date. To deepen the understanding of the role of these proteins in tomato plant development and yield, SlBBX28, a light-responsive gene, was constitutively silenced, resulting in plants with smaller leaves and fewer flowers per inflorescence. Moreover, SlBBX28 knockdown reduced hypocotyl elongation in darkness-grown tomato. Analyses of auxin content and responsiveness revealed that SlBBX28 promotes auxin-mediated responses. Altogether, the data revealed that SlBBX28 promotes auxin production and signaling, ultimately leading to proper hypocotyl elongation, leaf expansion, and inflorescence development, which are crucial traits determining tomato yield.


Assuntos
Arabidopsis , Solanum lycopersicum , Arabidopsis/metabolismo , Flores , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
Invest New Drugs ; 40(3): 643-649, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35038126

RESUMO

Introduction We analyzed the outcomes of patients with advanced cancers in our institution treated with off-label drugs targeting actionable genomic alteration based on next-generation sequencing who did not qualify for clinical trials. Purposes Our study endpoint was objective tumor response or stable disease at 16 weeks or later after treatment initiation. Methods Sixteen patients were included, 8 treated with immune checkpoint inhibitors targeting PD-L1 expression or TP53 mutations and 8 with other drugs. Tumors were analyzed based on PD-L1 expression, TP53 mutation, MSI, TMB, MMR status, and other targetable alterations. Results Of the 16 patients in the intention-to-treat group, no patients had an objective response after 16 weeks. Eleven patients met the primary study endpoint with stable disease, 8 in the immune checkpoint inhibitors group and 3 in the non-immune checkpoint inhibitors group. Using the log-rank test, the p-value for the difference between groups was 0.008. Conclusions In this study with off-label drugs, immune checkpoint inhibitors targeting TP53 mutations or PD-L1 expression were superior to the other drugs. This suggests the possibility of off-label use of anti-cancer drugs based on next-generation sequencing to be beneficial for advanced cancer patients without other therapeutic options.


Assuntos
Antígeno B7-H1 , Neoplasias Pulmonares , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Uso Off-Label
14.
Phys Chem Chem Phys ; 24(29): 17751-17758, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35843227

RESUMO

In this work, an investigation on the ionization potentials (IPs) of the glycine molecule (NH2CH2COOH) is presented. IPs ranging up to ∼20 eV were probed for each of the six conformations considered, with the referred threshold being chosen based on both: (i) the observations by recent photoelectron-photoion coincidence (PEPICO) experiments and (ii) the energy range of relevance to the modeling of other photo-induced processes (e.g., photoionization). For computing the IPs, the equation-of-motion ionization potential coupled-cluster with single and double excitations method (EOMIP-CCSD) was employed with large correlation consistent aug-cc-pVXZ and aug-cc-pCVXZ (X = D, T, and Q) basis sets. Extrapolation to the complete basis set limit and consideration of core electron correlation effects were also taken into account. Subsequently, the Feller-Peterson-Dixon (FPD) approach was used for considering all the contributions and to obtain accurate IPs. In addition, coupled-cluster with single and double excitations as well as perturbative triples, CCSD(T), was also used with the aug-cc-pVTZ basis set. When compared to each other, results obtained through the use of these approaches yielded excellent agreement. In general, the outcomes from the present work provide additional information to the insights gathered from the recent PEPICO experiments as well as accurate IPs for all 6 conformations of glycine using an approach based on high levels of theory. Hence, it is expected that other investigations focusing on photo-induced processes originating from NH2CH2COOH (for instance, the computational modeling of its photoionization) will be motivated for study in the future.


Assuntos
Elétrons , Glicina , Simulação por Computador , Conformação Molecular
15.
PLoS Genet ; 15(12): e1008551, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31887136

RESUMO

Aspergillus fumigatus causes invasive aspergillosis, the most common life-threatening fungal disease of immuno-compromised humans. The treatment of disseminated infections with antifungal drugs, including echinocandin cell wall biosynthesis inhibitors, is increasingly challenging due to the rise of drug-resistant pathogens. The fungal calcium responsive calcineurin-CrzA pathway influences cell morphology, cell wall composition, virulence, and echinocandin resistance. A screen of 395 A. fumigatus transcription factor mutants identified nine transcription factors important to calcium stress tolerance, including CrzA and ZipD. Here, comparative transcriptomics revealed CrzA and ZipD regulated the expression of shared and unique gene networks, suggesting they participate in both converged and distinct stress response mechanisms. CrzA and ZipD additively promoted calcium stress tolerance. However, ZipD also regulated cell wall organization, osmotic stress tolerance and echinocandin resistance. The absence of ZipD in A. fumigatus caused a significant virulence reduction in immunodeficient and immunocompetent mice. The ΔzipD mutant displayed altered cell wall organization and composition, while being more susceptible to macrophage killing and eliciting an increased pro-inflammatory cytokine response. A higher number of neutrophils, macrophages and activated macrophages were found in ΔzipD infected mice lungs. Collectively, this shows that ZipD-mediated regulation of the fungal cell wall contributes to the evasion of pro-inflammatory responses and tolerance of echinocandin antifungals, and in turn promoting virulence and complicating treatment options.


Assuntos
Aspergillus fumigatus/patogenicidade , Cálcio/efeitos adversos , Farmacorresistência Fúngica , Aspergilose Pulmonar/microbiologia , Fatores de Transcrição/genética , Animais , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Caspofungina , Parede Celular/metabolismo , Modelos Animais de Doenças , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Camundongos , Mutação , Aspergilose Pulmonar/imunologia , Estresse Fisiológico , Virulência
16.
Lasers Med Sci ; 37(3): 2033-2043, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34812971

RESUMO

This study aimed to characterize the aluminum phthalocyanine chloride (AlClPc) encapsulated in chitosan nanoparticles (CN) and apply it in antimicrobial photodynamic therapy (aPDT) on multispecies biofilm composed of Streptococcus mutans, Lactobacillus casei, and Candida albicans to analyze the antimicrobial activity and lactate production after treatment. Biofilms were formed in 24-well polystyrene plates at 37 °C for 48 h under microaerophilia. The following groups were evaluated (n = 9): as a positive control, 0.12% chlorhexidine gluconate (CHX); phosphate-buffered saline (PBS) as a negative control; 2.5% CN as release vehicle control; the dark toxicity control of the formulations used (AlClPc and AlClPc + CN) was verified in the absence of light; for aPDT, after 30 min incubation time, the photosensitizers at a final concentration of 5.8 × 10-3 mg/mL were photoirradiated for 1 min by visible light using a LED device (AlClPc + L and AlClPc + CN + L) with 660 nm at the energy density of 100 J/cm2. An in vitro kit was used to measure lactate. The biofilm composition and morphology were observed by scanning electron microscopy (SEM). The antimicrobial activity was analyzed by quantifying colony forming units per mL (CFU/mL) of each microorganism. Bacterial load between groups was analyzed by ANOVA and Tukey HSD tests (α = 0.05). A lower lactate dosage was observed in the aPDT AlClPc + CN + L and CHX groups compared to the CN and AlClPc groups. The aPDT mediated by the nanoconjugate AlClPc + CN + L showed a significant reduction in the viability of S. mutans (3.18 log10 CFU/mL), L. casei (4.91 log10 CFU/mL), and C. albicans (2.09 log10 CFU/mL) compared to the negative control PBS (p < 0.05). aPDT using isolated AlClPc was similar to PBS to the three microorganisms (p > 0.05). The aPDT mediated by the nanoconjugate AlClPc + CN + L was efficient against the biofilm of S. mutans, L. casei, and C. albicans.


Assuntos
Quitosana , Nanopartículas , Fotoquimioterapia , Biofilmes , Quitosana/farmacologia , Indóis , Compostos Organometálicos , Fármacos Fotossensibilizantes/farmacologia , Streptococcus mutans/fisiologia
17.
Odontology ; 110(3): 535-544, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35044577

RESUMO

The purpose of this study was to investigate whether the root perforation repair with mineral aggregate-based cements affects the retention of customized fiberglass posts to bovine intraradicular dentin. Sixty-four bovine mandibular incisors had their root canals endodontically treated and prepared for fiberglass posts luting. Teeth were randomly distributed into four groups (n = 16), according to the cement used for the perforations repair (MTA HP; calcium aluminate cement-CAC; and CAC + calcium carbonate nanoparticles-nano-CaCO3) and control group (no perforation). The groups were redistributed according to the fiberglass posts luting protocol (n = 8): total-etching (TE) (MTA HP/TE; CAC/TE; CAC + CaCO3/TE and control/TE) and self-etching (SE) (MTA HP/SE; CAC/SE; CAC + CaCO3/SE and control/SE). Roots were sectioned into 1.3 mm-thick dentin slices obtaining samples that were submitted to the push-out test in Universal Testing Machine (Instron, Model 4444-0.5 mm/min). The fractured samples were analyzed under stereomicroscope and Scanning Electron Microscope (SEM). CAC/TE and CAC/SE groups had significant difference between the cervical and middle thirds (p < 0.05). When the root thirds were not considered, CAC/SE had the lowest bond strength and differed statistically from CAC/TE and CAC + CaCO3/TE groups, which had the highest mean bond strength values (p < 0.05). The root perforations repair did not affect the bond strength of resin cement/customized fiberglass posts to bovine dentin. The increase in bond strength is luting protocol dependent.


Assuntos
Colagem Dentária , Técnica para Retentor Intrarradicular , Animais , Bovinos , Colagem Dentária/métodos , Cavidade Pulpar , Dentina , Vidro/química , Teste de Materiais , Minerais/farmacologia , Cimentos de Resina/química
18.
J Sci Food Agric ; 102(14): 6511-6529, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35567412

RESUMO

BACKGROUND: Climate change is the main cause of biotic and abiotic stresses in plants and affects yield. Therefore, we sought to carry out a study on future changes in the agroclimatic conditions of banana cultivation in Brazil. The current agroclimatic zoning was carried out with data obtained from the National Institute of Meteorology related to mean air temperature, annual rainfall, and soil texture data in Brazil. The global climate model BCC-CSM1.1 (Beijing Climate Center-Climate System Model, version 1.1), adopted by the Intergovernmental Panel on Climate Change, corresponding to Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0, and 8.5 for the period 2050 (2041-2060) and 2070 (2061-2080), obtained through the CHELSA V1.2 platform, was chosen for the climate projections of the Coupled Model Intercomparison Project 5. Matrix images at a depth of 5-15 cm, obtained through the product of the SoilGrids system, were used for the texture data. ArcGIS version 10.8 was used to construct the maps. RESULTS: Areas favorable to the crop plantation were classified as suitable when air temperature TAIR was between 20 and 29 °C, annual rainfall RANNUAL between 1200 and 1900 mm, and soil clay content CSOIL between 30 and 55%. Subsequently, the information was reclassified, summarizing the classes into preferential, recommended, little recommended, and not recommended. The current scenario shows a preferential class of 8.1%, recommended of 44.6%, little recommended of 47.1%, and not recommended of 0.1% for the Brazilian territory. CONCLUSION: The results show no drastic changes in the total area regarding the classes, but there is a migration from these zones; that is, from tropical to subtropical and temperate regions. RCP 8.5-2070 (2061-2080) showed trends with negative impacts on arable areas for banana cultivation at the end of the century. © 2022 Society of Chemical Industry.


Assuntos
Mudança Climática , Musa , Brasil , Argila , Solo
19.
Int J Environ Health Res ; 32(12): 2810-2819, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34689675

RESUMO

Brazil has become the epicenter of coronavirus disease, and the São Paulo State has the worst scenario. This study evaluated the effect of the COVID-19 in dentists of São Paulo State, Brazil. A self-administered web-based survey with 33 multiple-choice questions was sent to dentists. Descriptive statistics were used to assess the 302 valid responses. Data were analyzed by Chi-square, McNemar and Wilcoxon tests (α = 0.05). Most of the participants aged until 34 years (61.6%) and were female (74.5%). They reduced work to less than 20 h per week. Monthly remuneration was reduced (86.8%). Personal protective equipment at the office was changed (p < 0.05). A few dentists (7.6%) had COVID-19, and more than 99% were aware of the disease. Most of the participants (90.2%) were insecure about being contaminated. The dentists of São Paulo State had coronavirus knowledge and have adopted strict biosafety protocols, but the pandemic affected their financial and psychological features.


Assuntos
COVID-19 , Feminino , Humanos , Idoso , Masculino , COVID-19/epidemiologia , Brasil/epidemiologia , Pandemias , Equipamento de Proteção Individual , Surtos de Doenças , Inquéritos e Questionários
20.
Virus Genes ; 57(2): 222-227, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33566217

RESUMO

Giant viruses have brought new perspectives on the virosphere. They have been increasingly described in humans, including in several metagenomic studies. Here, we searched into the metagenome of the 5300-year-old Ötzi mummy for the presence of giant virus-related sequences using MG-Digger pipeline. We found 19 reads (0.00006% of the total read number) that best matched (mean ± standard deviation (range) for e-values of 5.0E-6 ± 1.4E-6 (6.0E-5-4.0E-10) and for amino acid identity of 69.9 ± 8.7% (46.4-84.9%) and most significantly with sequences from various giant viruses, including mostly mimiviruses. This expands current knowledge on the ubiquity and relationship with humans of giant viruses.


Assuntos
Vírus Gigantes/genética , Metagenoma , Múmias/virologia , Conjuntos de Dados como Assunto , Humanos
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