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1.
Crit Rev Microbiol ; : 1-11, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497208

RESUMO

INTRODUCTION: In 2022, the World Health Organization published a report encouraging researchers to focus on Candida spp. to strengthen the global response to fungal oral infections and antifungal resistance. In the context of innovative research, it seems pertinent to investigate the antifungal potential of natural extracts of plants and the methodology involved in the recent reports. The aim of this systematic review is to identify the current state of in vitro research on the evaluation of the ability of plant extracts to inhibit Candida spp. MATERIAL AND METHODS: A bibliographic search has been developed to on a 10-year period to identify which plant extracts have an antifungal effect on the Candida spp. found in the oral cavity. RESULTS: A total of 20 papers were reviewed and fulfilled all the selection criteria and were included in the full data analysis. DISCUSSION: Plants have been tested in a wide range of states - whole extracts, extraction of particular components such as flavonoids or polyphenols, or even using the plant to synthesize nanoparticles. Of forty-five plants tested, five of them did not show any effect against Candida spp., which weren't part of the same family. There is a wide range of plant that exhibit antifungal proprieties. CONCLUSION: Many plants have been tested in a wide range of states - whole extracts, extraction of components such as flavonoids or polyphenols, or even using the plant to synthetize nanoparticles. The combination of plants, the addition of plants to a traditional antifungal and the interference with adhesion provided by some plants seem to be promising strategies. Nonetheless, on contrary to drugs, there is a critical lack of standardization on methodologies and protocols, which makes it difficult to compare data and, consequently, to conclude, beyond doubts, about the most promising plants to fight Candida spp. oral infections.

2.
Eur Biophys J ; 52(8): 661-671, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37542583

RESUMO

The kinetics of an ion channel are classically understood as a random process. However, studies have shown that in complex ion channels, formed by multiple subunits, this process can be deterministic, presenting long-term memory. Staphylococcus aureus α-hemolysin (α-HL) is a toxin that acts as the major factor in Staphylococcus aureus virulence. α-HL is a water-soluble protein capable of forming ion channels into lipid bilayers, by insertion of an amphipathic  ß-barrel. Here, the α-HL was used as an experimental model to study memory in ion channel kinetics. We applied the approximate entropy (ApEn) approach to analyze randomness and the Detrended Fluctuation Analysis (DFA) to investigate the existence of long memory in α-HL channel kinetics. Single-channel currents were measured through experiments with α-HL channels incorporated in planar lipid bilayers. All experiments were carried out under the following conditions: 1 M NaCl solution, pH 4.5; transmembrane potential of + 40 mV and temperature 25 ± 1 °C. Single-channel currents were recorded in real-time in the memory of a microcomputer coupled to an A/D converter and a patch-clamp amplifier. The conductance value of the α-HL channels was 0.82 ± 0.0025 nS (n = 128). The DFA analysis showed that the kinetics of α-HL channels presents long-term memory ([Formula: see text] = 0.63 ± 0.04). The ApEn outcomes showed low complexity to dwell times when open (ApEno = 0.5514 ± 0.28) and closed (ApEnc = 0.1145 ± 0.08), corroborating the results of the DFA method.


Assuntos
Proteínas Hemolisinas , Canais Iônicos , Bicamadas Lipídicas , Proteínas Hemolisinas/metabolismo , Canais Iônicos/metabolismo , Cinética , Staphylococcus aureus
3.
Int Urogynecol J ; 34(8): 1849-1858, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36780018

RESUMO

INTRODUCTION AND HYPOTHESIS: The objectives were to evaluate clinical and anatomical parameters assessed by three-dimensional pelvic floor ultrasound (3D ultrasound) in parous and nulliparous women of childbearing age and to assess underreported symptoms of sexual dysfunction (SD), urinary incontinence (UI) and flatus incontinence (FI). METHODS: Women without complaints of pelvic floor dysfunction, aged 20-50 years, were eligible for this prospective cross-sectional study. They completed the King's Health Questionnaire, Female Sexual Function Index and St Mark's Incontinence Score adapted for this study. Next, a physical examination and 3D ultrasound were performed. The scores obtained in the questionnaires were compared with the 3D ultrasound data. RESULTS: In total, 326 women were invited to participate. Of these, 203 women met the inclusion criteria, and their cases were classified as nulliparity (NU, 59), vaginal delivery (VD, 80), forceps delivery (FD, 18) and caesarean section (CS, 48). These groups were homogeneous regarding age (p=0.096), parity (p=0.051) and body mass index (p=0.06). The hiatal dimension (HD; p=0.003) and transverse diameter (TD) (p=0.001) were significantly different among the groups. Compared with the NU and CS groups, the VD and FD groups had an increased HD and TD. The frequencies of underreported symptoms identified by questionnaires were as follows: SD (46.3%), UI (35%) and FI (28%). After VD and FD, women were more likely to present UI (p<0.001), FI (p<0.001) and SD (p=0.002) than the women with NU and those who had undergone a CS. UI was related to a greater HD (p=0.002) and anteroposterior diameter (p=0.022), FI was associated with a thinner left pubovisceral muscle (p=0.013), and SD was related to a greater HD (p=0.026). CONCLUSIONS: Three-dimensional ultrasound can identify mild morphological changes in young women with apparently normal physical examinations, mainly after VD and FD. In such individuals, these findings are associated with higher incidences of underreported sexual, urinary and anal symptoms.


Assuntos
Incontinência Fecal , Disfunções Sexuais Fisiológicas , Incontinência Urinária , Feminino , Gravidez , Humanos , Paridade , Cesárea/efeitos adversos , Diafragma da Pelve/diagnóstico por imagem , Estudos Transversais , Estudos Prospectivos , Incontinência Fecal/etiologia , Incontinência Urinária/diagnóstico por imagem , Incontinência Urinária/etiologia , Incontinência Urinária/epidemiologia , Parto Obstétrico/métodos
4.
Crit Rev Food Sci Nutr ; 62(29): 8230-8246, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34036844

RESUMO

According to the European Union regulation, some countries have established a pre-market notification system for food supplements while others have not. As this regulation is unfulfilled, a notified and marketed food supplement ingredient in one country may be forbidden in another. Even though food supplements shall not be placed on the market if unsafe, some products may still expose the consumers to risks. The risk is increased by easier access due to worldwide dissemination fostered by the internet and free movement of goods in the European Union. The Rapid Alert System for Food and Feed and the Emerging Risks Exchange Network are described. To date, the European Union legislation does not include a provision to establish a dedicated vigilance system for food supplements (Nutrivigilance). Six European Union countries have nevertheless set up national systems, which are presented. The present lack of European Union data collection harmonization, does not allow easy cooperation between countries. This article advocates for creating a coordinated European Nutrivigilance System to detect and scrutinize adverse effects of food supplements. This, to help in directing science-based risk assessments and reinforce the science-based decision of policy makers to improve public health safety.


Assuntos
Qualidade de Produtos para o Consumidor , Saúde Pública , Suplementos Nutricionais/efeitos adversos , União Europeia , Legislação sobre Alimentos
5.
Morphologie ; 106(353): 92-97, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33775545

RESUMO

BACKGROUND: Coronary arterial dominance and myocardial bridges have clinical implications, since a left dominant pattern associated to the presence of myocardial bridges is often associated to a higher incidence of arteriosclerosis and higher mortality by myocardial infarction. OBJECTIVE: To determine the presence and position of myocardial bridges and their relation with coronary arterial dominance. METHODS: Fifty-seven human cadaveric hearts were analyzed into three groups, as follows: right dominance; left dominance; codominance. Each group was then divided into two subgroups: with or without myocardial bridges. Finally, each subgroup with myocardial bridges was classified according to the position of the myocardial bridge according to the main axis of the heart (proximal, middle and distal third). RESULTS: The right dominance occurred in most hearts (30 hearts-52,6%). Twenty-three myocardial bridges (40,3%) were identified and mostly occurred on left dominant hearts (22,8%). The pattern of coronary dominance presented a statistically significant correlation with the presence of myocardial bridges (P=0.048). The middle third of the heart axis showed the highest occurrence of myocardial bridges. CONCLUSION: These findings suggest there is a clear relationship between the presence of myocardial bridges and left dominant pattern. Middle third of the heart axis present the higher occurrence of myocardial bridges. Knowledge of the myocardial bridges morphology is of great clinical significance, improving patient care.


Assuntos
Vasos Coronários , Miocárdio , Brasil/epidemiologia , Vasos Coronários/anatomia & histologia , Humanos , Incidência
6.
J Appl Microbiol ; 131(2): 671-681, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33342053

RESUMO

AIMS: To investigate the effects of the lectin from Punica granatum sarcotesta (PgTeL) on growth, viability, cell structure, biofilm formation and chitinase activity of Listeria monocytogenes. In addition, the effect of PgTeL on the adhesion and invasion of human cells (HeLa) was determined. METHODS AND RESULTS: PgTeL showed bacteriostatic and bactericidal effects on the strains L. monocytogenes N53-1 and EGD-e, causing morphometric alterations, cell aggregation, strong deformation and cell disruption. PgTeL inhibited biofilm formation by EGD-e and N53-1 and also interfered with the adhesion and invasion processes of EGD-e and N53-1 in HeLa cells. Finally, the chitinase activity of L. monocytogenes EGD-e was reduced in the presence of PgTeL, which can be involved in the inhibition of adhesion process. CONCLUSION: PgTeL is an antibacterial agent against L. monocytogenes, inhibiting growth and promoting cell death, as well as impairing biofilm formation and bacterial adhesion and invasion into human cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The results stimulate future investigations on the potential of PgTeL for protection of contamination in food products.


Assuntos
Antibacterianos/farmacologia , Lectinas/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Punica granatum , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Células HeLa , Humanos , Listeria monocytogenes/fisiologia
7.
Acta Biotheor ; 69(4): 697-722, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34043104

RESUMO

Ion channels are transport proteins present in the lipid bilayers of biological membranes. They are involved in many physiological processes, such as the generation of nerve impulses, hormonal secretion, and heartbeat. Conformational changes in the ion channel-forming protein allow the opening or closing of pores to control the ionic flux through the cell membranes. The opening and closing of the ion channel have been classically treated as a random kinetic process, known as a Markov process. Here the time the channel remains in a given state is assumed to be independent of the condition it had in the previous state. More recently, however, several studies have shown that this process is not random but a deterministic one, where both the open and closed dwell-times and the ionic current flowing through the channel are history-dependent. This property is called long memory or long-range correlation. However, there is still much controversy regarding how this memory originates, which region of the channel is responsible for this property, and which models could best reproduce the memory effect. In this article, we provide a review of what is, where it is, its possible origin, and the mathematical methods used to analyze the long-term memory present in the kinetic process of ion channels.


Assuntos
Canais Iônicos , Modelos Biológicos , Canais Iônicos/metabolismo , Cinética , Cadeias de Markov
8.
Pancreatology ; 20(4): 729-735, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32332003

RESUMO

BACKGROUND: Current guidelines for IPMN include an elevated serum carbohydrate antigen (CA) 19-9 among the worrisome features. However, the correlation of CA 19-9 with histological malignant features and survival is unclear. Serum CEA is also currently used for preoperative management of IPMN, although its measurement is not evidence-based. Accordingly, we aimed to assess the role of these tumor markers as predictors of malignancy in IPMN. METHODS: IPMN resected between 1998 and 2018 at Massachusetts General Hospital were analyzed. Clinical, pathological and survival data were collected and compared to preoperative levels of CA 19-9 and CEA. Receiver operating characteristic (ROC) and Cox regression analyses were performed considering cut-offs of 37 U/ml (CA 19-9) and 5 µg/l (CEA). RESULTS: Analysis of 594 patients showed that preoperative CA 19-9 levels > 37 U/ml (n = 128) were associated with an increased likelihood of invasive carcinoma when compared to normal levels (45.3% vs. 18.0%, P < 0.001), while there was no difference with respect to high-grade dysplasia (32.9% vs 31.9%, P = 0.88). The proportion of concurrent pancreatic cancer was higher in patients with CA 19-9 > 37 U/ml (17.2% vs 4.9%, P < 0.001). An elevated CA 19-9 was also associated with worse overall and disease-free survival (HR = 1.943, P = 0.007 and HR = 2.484, P < 0.001 respectively). CEA levels did not correlate with malignancy. CONCLUSION: In patients with IPMN, serum CA19-9 > 37 U/ml is associated with invasive IPMN and concurrent pancreatic cancer as well as worse survival, but not with high-grade dysplasia. Serum CEA appears to have minimal utility in the management of these patients.


Assuntos
Antígeno CA-19-9/sangue , Neoplasias Intraductais Pancreáticas/sangue , Neoplasias Intraductais Pancreáticas/patologia , Adenocarcinoma Mucinoso , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Intraductais Pancreáticas/terapia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Sensibilidade e Especificidade , Neoplasias Pancreáticas
9.
Med Vet Entomol ; 34(4): 488-492, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32293047

RESUMO

Rhipicephalus microplus Canestrini, 1887 (Arachnida: Ixodidae) is a mandatory bloodsucking ectoparasite, and it is considered one of the main sanitary problems in livestock. In the development of new technologies for controlling ticks, Metarhizium anisopliae complex (M. anisopliae s. l.) Sorokin, 1883 (Ascomycota: Clavicipitaceae) have been shown to be an effective and safe alternative. However, when applied in the field, abiotic factors may directly influence their microbial activity, and different oily adjuvants enhance fungal efficacy, stability and viability under environmental conditions. Here, the efficacy of two Metarhizium anisopliae s.l. isolates (CG 148 and CG 347) were compared in mineral oil (MO) or vegetable oil (VO) emulsions to control cattle ticks under semi-natural conditions, as well as their persistence in the soil over time. Engorged female ticks were placed on the soil of grass pots previously treated or not with conidial oil-in-water emulsions. Both M. anisopliae s.l. oil-in-water emulsions tested were able to control R. microplus, achieving up to 100% daily efficacy, and remained viable in the soil for up to 60 days after treatment. These results show the prospective applicability of Metarhizium spp. to control the cattle tick and a real possibility for its control in the environment.


Assuntos
Agentes de Controle Biológico/farmacologia , Metarhizium/patogenicidade , Rhipicephalus/efeitos dos fármacos , Infestações por Carrapato/veterinária , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Composição de Medicamentos/métodos , Emulsões/farmacologia , Feminino , Ixodidae/efeitos dos fármacos , Ixodidae/microbiologia , Larva/parasitologia , Gado/parasitologia , Controle Biológico de Vetores/métodos , Praguicidas/farmacologia , Rhipicephalus/microbiologia , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/tratamento farmacológico
10.
Bull Environ Contam Toxicol ; 105(1): 86-94, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32577782

RESUMO

The distribution, seasonal variation and sources of 16 polycyclic aromatic hydrocarbons (PAH) from suspended particulate matter (SPM) of the Aurá River, a small amazon typical river located in Northern Brazil, were determined. Gas chromatography-mass spectrometry analysis of SPM revealed a mixture of PAH from different origins and a seasonal variation of PAH primary source for the studied area. Pyrene was the dominant PAH in both studied periods. Total PAH content (ΣPAH) ranged from lower than quantification limit (< LOQ) to 2498.2 ng g-1 dw during the dry season and < LOQ to 2865.8 ng g-1 dw during the wet season. Low molecular weight PAH (LMW) represented 51% of ΣPAH during the dry season and 29% during the wet season. It was noted, by comparing previous data, that the main source of these compounds was altered after the deactivation of an irregular landfill next to the river.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Brasil , China , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Material Particulado/análise , Pirenos , Rios/química , Estações do Ano , Urbanização
11.
Bioorg Med Chem ; 27(8): 1449-1455, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30528164

RESUMO

Extracellular adenosine 5'-triphosphate (ATP) triggers the P2X7 receptor (P2X7R) ionic channel to stimulate the release of the interleukin-IL-1ß cytokine into macrophages. The current study explored the reaction of six structurally diverse triazole derivatives on P2X7-mediated dye uptake into murine peritoneal macrophages. P2X7R activity determined by ATP-evoked fluorescent dye uptake. Triazole derivatives toxicity measured using dextran rhodamine exclusion based colorimetric assay. A740004 and BBG, both P2X7R antagonist, inhibited ATP-induced dye uptake. In contrast, the derivatives 5a, 5b, 5e, and 5f did not diminish P2X7R activity in concentrations until 100 µM. 5c and 5d analogs caused a potent inhibitory activity on P2X7-induced dye uptake. Dextran Rhodamine exclusion measurements after 24 h of continuous treatment with triazole derivatives indicated a moderated toxicity for all molecules. In conclusion, this study showed that a series of new hybrid 1,2,3-triazolic naphthoquinones reduces P2X7R-induced dye uptake into murine macrophages. In silico analysis indicates a good pharmacokinetic profile and molecular docking results of these analogs indicate the potential to bind into an allosteric site located into the P2X7R pore and juxtaposed with the ATP binding pocket. In this manner, the compounds 5c and 5d may be used as a scaffold for new P2X7R inhibitors with reduced toxicity, and good anti-inflammatory activity.


Assuntos
Naftoquinonas/química , Antagonistas do Receptor Purinérgico P2X/química , Receptores Purinérgicos P2X7/metabolismo , Triazóis/química , Sítio Alostérico , Animais , Sítios de Ligação , Células CACO-2 , Linhagem Celular , Corantes/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Acoplamento Molecular , Permeabilidade/efeitos dos fármacos , Estrutura Terciária de Proteína , Antagonistas do Receptor Purinérgico P2X/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/química , Triazóis/metabolismo , Triazóis/farmacologia
12.
Med Oral Patol Oral Cir Bucal ; 24(4): e483-e490, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31232387

RESUMO

BACKGROUND: Since implant placement on diabetic patients still is a controversial topic and systematic reviews are at the top of scientific evidence hierarchy, a thorough assessment of the methodological quality of these reviews must be performed to inform clinicians if their conclusions and recommendations can be followed on clinical practice. An overview of systematic reviews was performed with the purpose to assess the methodological quality of systematic reviews regarding dental implant placement on diabetic patients. In addition, we presented a synthesis of clinical outcomes about the focused theme. MATERIAL AND METHODS: An online search was performed on MEDLINE via PubMed, EMBASE, DARE-Cochrane, Scopus, Web of Science, LILACS, and SIGLE via Open Grey. Searches were conducted from database inception to May 2018. Systematic review articles with or without meta-analysis about the placement of dental implants on diabetic patients were included. Exclusion criteria were: articles whose primary outcome was not the survival/success rate of dental implants on diabetic patients; studies that do not relate the survival/success rate of dental implants with diabetes; duplicated papers. Methodological quality assessment was performed with AMSTAR. A descriptive synthesis of clinical outcomes was performed. RESULTS: We identified 1.661 initial hits and eight articles were selected for overview (kappa=0.83; strong agreement). Six studies presented moderate methodological quality and two showed high methodological quality. Implant survival rate ranged from 31.8% to 100% and data from four meta-analysis showed that diabetes does not affect implant survival rate. On the other hand, data from two meta-analysis for marginal bone loss showed that diabetes statistically affects this outcome. CONCLUSIONS: Two of the eight included studies presented high methodological quality and their meta-analysis showed that implant placement on diabetic patients does not affect implant survival rate and statistically affects marginal bone loss. However, clinicians must be aware that marginal bone loss values were not clinically relevant and may not be safe to follow the conclusions and recommendations of these studies.


Assuntos
Implantes Dentários , Diabetes Mellitus , Falha de Restauração Dentária , Humanos
13.
Med Oral Patol Oral Cir Bucal ; 24(4): e518-e528, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31232386

RESUMO

BACKGROUND: Alveolar infection is known as a risk factor for implant failure. Current meta-analysis on the theme could not prove statistically that immediate dental implants placed into infected sites have a higher risk of failure than immediate dental implants placed into non-infected sites. The purpose of this meta-analysis was to determine the effectiveness of immediate dental implants placed into infected versus non-infected sites. MATERIAL AND METHODS: Seven databases were sought by two reviewers. Randomized or non-randomized clinical trials that compared the placement of dental implants into infected versus non-infected sites were eligible for the study. Exclusion criteria were: papers in which the survival rate was not the primary outcome; papers without a control group; studies with less than one year of follow-up; studies whose patients did not receive antibiotic therapy; studies with medically compromised patients; duplicated papers. Risk of bias assessment was performed with the Cochrane Collaboration tool. RESULTS: Of the 3.253 initial hits, 8 studies were included in both qualitative and quantitative synthesis (kappa=0.90; very good agreement). Forest plot for implant failure showed that immediate implants placed into infected sites presented a statistically significant risk of failure that is almost 3 times higher than when placed into non-infected sites (risk ratio= 2.99; 95% confidence interval: 1.04, 8.56; p= 0.04; 935 implants; i2= 0%). Peri-implant outcomes showed no statistical difference. CONCLUSIONS: Immediate dental implants placed into infected sites presented a statistically significant higher risk of failure than immediate dental implants placed into non-infected sites. Peri-implant outcomes were not statistically affected in this intervention.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário , Implantação Dentária Endóssea , Falha de Restauração Dentária , Humanos , Resultado do Tratamento
14.
J Clin Microbiol ; 56(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29237789

RESUMO

Community-acquired pneumonia (CAP) is the leading cause of mortality in children under 5 years of age globally. To improve the management of CAP, we must distinguish CAP from other common pediatric conditions and develop better diagnostic methods to detect the causative organism, so as to best direct appropriate resources in both industrialized and developing countries. Here, we review the diagnostic modalities available for identifying viruses and bacteria in the upper and lower respiratory tract of children, with a discussion of their utility and limitations in diagnosing CAP in children.


Assuntos
Bactérias/isolamento & purificação , Infecções Comunitárias Adquiridas/diagnóstico , Técnicas Microbiológicas/normas , Técnicas de Diagnóstico Molecular/normas , Pneumonia/diagnóstico , Vírus/isolamento & purificação , Bactérias/genética , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Humanos , Técnicas Microbiológicas/tendências , Técnicas de Diagnóstico Molecular/tendências , Pneumonia/microbiologia , Pneumonia/virologia , Sistemas Automatizados de Assistência Junto ao Leito , Valor Preditivo dos Testes , Sistema Respiratório/microbiologia , Sistema Respiratório/virologia , Vírus/genética
15.
Cryobiology ; 81: 4-11, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29524383

RESUMO

The cryopreservation process must be improved to enhance oocyte cryosurvival and functionality. Two protocols with different cryoprotectants (CPAs), containing either ethylene glycol (EG), dimethyl sulfoxide (DMSO) and sucrose (EGDMSO) or 1,2-propanediol and sucrose (PrOH) were evaluated. In both protocols, calcium (Ca2+) free or -containing base media were tested. Oocytes were subjected to vitrification or only exposed to CPAs without immersion in liquid nitrogen. Oocyte's viability, cortical granules location and competence for development after fertilization were assessed. Finally, fatty acid composition and membrane permeability of oocytes exposed to CPAs were analyzed. Independently of Ca2+ concentration in the vitrification media, the development rates were higher in oocytes vitrified with EGDMSO protocols (p = 0.0005). After warming, higher cleavage rates were obtained in EGDMSO + Ca2+ compared to the PrOH without Ca2+ protocol (p = 0.02). Oocytes exposed to PrOH without Ca2+ presented lower cleavage rates compared to control (p = 0.04). An enhanced premature zona hardening in vitrified oocytes as well as lower concentrations of the fatty acids c11:18:1 and 20:4n-6 in cumulus oocyte complexes exposed to PrOH protocols were identified. The oocytes minimum volume and permeability were affected by the exposure to PrOH and Ca2+ (p ≤ 0.007). In conclusion, the most effective protocol for bovine oocytes cryopreservation combines EG and DMSO, independently of Ca2+ concentration in the media. A higher toxicity and an incomplete depletion of water during PrOH loading may hamper oocyte viability. The type of CPAs and Ca2+ interfered differentially on oocyte pathways to functionality, and this should be considered when choosing a cryopreservation protocol.


Assuntos
Cálcio/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Oócitos/efeitos dos fármacos , Vitrificação , Animais , Bovinos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Feminino , Propilenoglicol/farmacologia , Sacarose/farmacologia
16.
Int Endod J ; 51(8): 901-911, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29397005

RESUMO

AIM: To evaluate the antimicrobial action of an irrigant containing silver nanoparticles in an aqueous vehicle (AgNp), sodium hypochlorite and chlorhexidine against Enterococcus faecalis biofilm and infected dentinal tubules. METHODOLOGY: Bovine dentine blocks were used for E. faecalis biofilm development for 21 days and irrigated with 94 ppm AgNp solution, 2.5% NaOCl and 2% chlorhexidine for 5, 15 and 30 min. For infection of dentinal tubules with E. faecalis, dentine specimens from bovine incisors were submitted to a contamination protocol over 5 days, with eight centrifugation cycles on every alternate day, and irrigated with the same solutions and time intervals used for the biofilm. The specimens were stained with the Live/Dead technique and evaluated using a confocal laser scanning microscope (CLSM). The bioImage_L software was used for measurement of the total biovolume of biofilm in µm3 and percentage of viable bacteria (green cells) in biofilm and in dentinal tubules found after the irrigation. Statistical analyses were performed using Kruskal-Wallis and Dunn's tests for quantification of viable cells in biofilm, the Friedman test for comparisons of viable bacteria in dentinal tubules in different areas of the root canal and the Mann-Whitney U-test to compare the action of the irrigants between the two methods (P < 0.05). RESULTS: The AgNp solution eliminated fewer bacteria, but was able to dissolve more biofilm compared with chlorhexidine (P < 0.05). NaOCl had the greatest antimicrobial activity and biofilm dissolution capacity. AgNp solution had less antimicrobial action in infected dentinal tubules compared with NaOCl (P < 0.05). The AgNp solution after 5 min was more effective in eliminating planktonic bacteria in dentinal tubules than in biofilm, but at 30 min fewer viable bacteria were observed in the biofilm compared with intratubular dentine (P < 0.05). CONCLUSIONS: AgNp irrigant was not as effective against E. faecalis compared to solutions commonly used in root canal treatment. NaOCl is appropriate as an irrigant because it was effective in disrupting biofilm and in eliminating bacteria in biofilms and in dentinal tubules.


Assuntos
Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Irrigantes do Canal Radicular/farmacologia , Prata/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Bovinos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Nanopartículas Metálicas/administração & dosagem , Irrigantes do Canal Radicular/uso terapêutico , Prata/administração & dosagem , Prata/farmacologia
17.
Int Endod J ; 51(5): 556-563, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28470953

RESUMO

AIM: To report the main differences seen by direct visual inspection between original and counterfeit Reciproc instruments, together with an evaluation of instrument bending resistance, cyclic fatigue, surface finish, Vickers microhardness and chemical composition. METHODOLOGY: The visual aspects of original Reciproc R25 (VDW, Munich, Germany) and counterfeit Reciproc R25 instruments (claimed to be original, supposedly with dimensions similar to those of Reciproc R25 files, bought at www.mercadolivre.com.br) were evaluated under direct observation, stereomicroscopy and scanning electron microscope. The flexibility of original and counterfeit Reciproc R25 was determined via 45° bending tests according to the ISO 3630-1 specification. Instruments were also subjected to cyclic fatigue resistance, measuring the time to fracture in an artificial stainless steel canal with a 60° angle and 5-mm radius of curvature. The fracture surfaces of all fragments were examined under a scanning electron microscope. Roughness of the instruments was quantified using a profilometer, and the microhardness test was carried out using a Vickers hardness tester. Energy-dispersive X-ray microanalysis (EDX) was also carried out. Results were analysed statistically using the Student's t-test at a significance level of P < 0.05. RESULTS: Although the packaging of the original and counterfeit instruments was similar, a number of differences were observed such as ISO colour coding, measurement marks, stopper and morphologic characteristics. Original Reciproc instruments had significantly longer cyclic fatigue life and significantly lower bending resistance than counterfeit Reciproc instruments (P < 0.05), as well as significantly lower microhardness and roughness (P < 0.05). EDX results revealed differences in the chemical composition of the instruments (P < 0.05), indicating that the instruments were manufactured with different raw material. CONCLUSION: Original Reciproc files outperformed counterfeit instruments in all tests. It is thus important that identification strategies for these counterfeit instruments be developed, thereby preventing their inadvertent use.


Assuntos
Tratamento do Canal Radicular/instrumentação , Elasticidade , Falha de Equipamento , Fraude , Dureza , Humanos , Fenômenos Mecânicos , Microscopia Eletrônica de Varredura , Preparo de Canal Radicular/instrumentação
18.
Int J Obes (Lond) ; 41(9): 1394-1402, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28584298

RESUMO

BACKGROUND/OBJECTIVES: Glycerol is a key metabolite for lipid accumulation in insulin-sensitive tissues as well as for pancreatic insulin secretion. We examined the role of aquaporin-7 (AQP7), the main glycerol channel in ß-cells, and AQP12, an aquaporin related to pancreatic damage, in the improvement of pancreatic function and steatosis after sleeve gastrectomy in diet-induced obese rats. SUBJECTS/METHODS: Male Wistar obese rats (n=125) were subjected to surgical (sham operation and sleeve gastrectomy) or dietary (pair-fed to the amount of food eaten by sleeve-gastrectomized animals) interventions. The tissue distribution and expression of AQPs in the rat pancreas were analyzed by real-time PCR, western blotting and immunohistochemistry. The effect of ghrelin isoforms and glucagon-like peptide 1 (GLP-1) on insulin secretion, triacylglycerol (TG) accumulation and AQP expression was determined in vitro in RIN-m5F ß-cells. RESULTS: Sleeve gastrectomy reduced pancreatic ß-cell apoptosis, steatosis and insulin secretion. Lower ghrelin and higher GLP-1 concentrations were also found after bariatric surgery. Acylated and desacyl ghrelin increased TG content, whereas GLP-1 increased insulin release in RIN-m5F ß-cells. Sleeve gastrectomy was associated with an upregulation of AQP7 together with a normalization of the increased AQP12 levels in the rat pancreas. Interestingly, ghrelin and GLP-1 repressed AQP7 and AQP12 expression in RIN-m5F ß-cells. AQP7 protein was negatively correlated with intracellular lipid accumulation in acylated ghrelin-treated cells and with insulin release in GLP-1-stimulated ß-cells. CONCLUSIONS: AQP7 upregulation in ß-cells after sleeve gastrectomy contributes, in part, to the improvement of pancreatic steatosis and insulin secretion by increasing intracellular glycerol used for insulin release triggered by GLP-1 rather than for ghrelin-induced TG biosynthesis.


Assuntos
Aquaporinas/metabolismo , Grelina/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Células Secretoras de Insulina/fisiologia , Obesidade/cirurgia , Redução de Peso/fisiologia , Animais , Western Blotting , Modelos Animais de Doenças , Derivação Gástrica , Imuno-Histoquímica , Resistência à Insulina/fisiologia , Masculino , Obesidade/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
19.
Lupus ; 26(5): 529-536, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28394226

RESUMO

Neurologic disorders are among the most common and important clinical manifestations associated with systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS), mainly those that affect the central nervous system (CNS). Risk of cerebrovascular events in both conditions is increased, and stroke represents one of the most severe complications, with an incidence rate between 3% and 20%, especially in the first five years of diagnosis. This article updates the data regarding the risk factors, clinical manifestations, neuroimaging, and treatment of stroke in SLE and APS.


Assuntos
Síndrome Antifosfolipídica/complicações , Lúpus Eritematoso Sistêmico/complicações , Neuroimagem/métodos , Acidente Vascular Cerebral/epidemiologia , Anticorpos Antifosfolipídeos/metabolismo , Síndrome Antifosfolipídica/imunologia , Diagnóstico Precoce , Feminino , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem
20.
Eur J Clin Microbiol Infect Dis ; 36(2): 379-386, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27812805

RESUMO

The establishment of matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) in routine microbial identification boosted many developments towards high-throughput applications, including bacterial typing. However, results are still controversial for different bacterial species. We aim to evaluate the suitability of MALDI-TOF MS for typing clinically relevant multidrug resistant (MDR) Klebsiella pneumoniae subsp. pneumoniae clones using routine conditions and a previously validated chemometric analysis workflow. Mass spectra of 83 K. pneumoniae clinical isolates representing major human MDR clones [11 sequence types (STs), 22 PFGE-types] recovered in Portugal and Spain during outbreaks and non-outbreak situations (2003-2012) were obtained from cell extracts (CE) and intact cells (IC), and analysed with different chemometric tools. We observed a highly consistent peak pattern among isolates from different clones either with CE or IC, suggesting a high degree of conservation of biomolecules analysed (a large part corresponding to ribosomal proteins). Moreover, the low degree of agreement between MALDI-TOF MS and other methods (from 34.9 % to 43.4 % of correct assignments for CE and from 40.8 % to 70.1 % for IC) corroborates the low discriminatory potential of the technique at infraspecies level. Our results suggest a low discriminatory power of MALDI-TOF MS for clinically relevant MDR K. pneumoniae clones and highlight the need of developing tools for high-resolution typing in this species.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Klebsiella pneumoniae/química , Klebsiella pneumoniae/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Infecções por Klebsiella/microbiologia , Portugal , Espanha
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