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1.
J Dairy Sci ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608944

RESUMO

The diffusion of microplastics in the food supply chain is prompting public concern as their impact on human health is still largely unknown. The aim of this study was to qualitatively and quantitatively characterize microplastics in skim-milk powder samples (n = 16) from different European countries (n = 8) through Fourier-transform infrared micro-spectroscopy in attenuated total reflectance mode analysis. The present study highlights that the use of hot alkaline digestion has enabled the efficacious identification of microplastics in skim-milk powders used for cheese-making across European countries. The adopted protocol allowed detection of 29 different types of polymeric matrices for a total of 536 plastic particles. The most abundant microplastics were polypropylene, polyethylene, polystyrene, and polyethylene terephthalate. Microplastics were found in skim-milk powders in 3 different shapes (fiber, sphere, and irregular fragments) and 6 different colors (black, blue, brown, fuchsia, green, and gray). Results demonstrate the presence of microplastics in all skim-milk powder samples, suggesting a general contamination. Results of the present study will help to evaluate the impact of microplastics intake on human health.

2.
J Endod ; 50(2): 129-143, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37984798

RESUMO

INTRODUCTION: Citric acid (CA) conditioning may be a promising alternative to ethylenediaminetetraacetic acid (EDTA) in regenerative endodontic procedures, as reported to improve growth factors' release from dentin. This review systematically investigated the effect of CA conditioning on the growth factors release from dentin and cell behavior compared to EDTA conditioning. METHODS: Searches were conducted (PubMed/MEDLINE, Scopus, Web of Science, Embase, SciELO, Cochrane Library, and grey literature) until May-2023. Only in vitro studies that evaluated the effects of CA on growth factors' release from dentin and cell behavior outcomes compared to EDTA were included. The studies were critically appraised using a modified Joanna Briggs Institute's checklist. Meta-analysis was unfeasible. RESULTS: Out of the 335 articles screened, nine were included. Among these, three studies used dentin discs/roots from permanent human teeth; the rest combined them with stem cells. 10% CA for 5 or 10 minute was the most used protocol. Meanwhile, EDTA concentrations ranged from 10% to 17%. In eight studies examining the release of growth factors, five reported a significant release of transforming growth factor-ß after dentin conditioning with 10% CA compared to 17% EDTA. Regarding cell behavior (6 studies), three studies assessed cell viability. The findings revealed that 10% CA conditioning showed cell viability similar to those of 17% EDTA. Additionally, in two out of three studies, it was observed that 10% CA conditioning did not affect cell morphology. The studies had a low risk of bias. CONCLUSIONS: The use of 10% CA to condition dentin for 5-10 minutes resulted in a notable transforming growth factor -ß1 release, but its cell responses were similar to those of EDTA.


Assuntos
Endodontia Regenerativa , Humanos , Ácido Edético/farmacologia , Dentina/metabolismo , Ácido Cítrico/farmacologia , Ácido Cítrico/metabolismo , Células-Tronco/fisiologia , Fatores de Crescimento Transformadores/metabolismo , Fatores de Crescimento Transformadores/farmacologia
3.
Food Chem Toxicol ; 146: 111816, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33080330

RESUMO

The recent application of manufactured nanomaterials (MNMs) in plant protection products (PPPs) enhances stability of the active substance (a.s.), minimizes application losses, reduces the quantities of a.s., increases coverage on leaf surface, improves precise application, etc. Besides offering benefits, there is high concern about the potential risk for human and environment associated with the use of nanopesticides. In this study, a panel of complementary methodologies were used to determine size distribution and chemical identification of four different formulations of nanopesticides. Measurements were performed by dynamic light scattering (DLS), transmission electron microscopy (TEM), asymmetric field flow fractionation-multi angle light scattering (AF4-FFF-MALS), gas/liquid chromatography with mass spectrometry (GC-MS/MS, LC-MS/MS) or diode array detector (HPLC-DAD) and inductively coupled plasma mass spectrometry (ICP-MS). Results indicated average size values in the ranges: 27.4-148.7 nm by DLS; 39.1-82.0 nm by AF4-FFF-MALS; and 42-90 nm by TEM. Linked to these nanosized particles both organic active ingredients and inorganic ones were identified. In addition, the obtained data revealed that all the four PPPs contained more than 50% of particles with number size distribution between 1 and 100 nm and, according to the European Commission definition, they can be defined as nanopesticides.


Assuntos
Nanotecnologia , Praguicidas/química , Cromatografia Líquida de Alta Pressão/métodos , Fracionamento por Campo e Fluxo , Hidrodinâmica , Espectrometria de Massas/métodos , Microscopia Eletrônica de Transmissão , Praguicidas/análise
4.
Int Endod J ; 53(11): 1494-1505, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32767572

RESUMO

AIM: To evaluate the biocompatibility, induction of mineralization and antimicrobial activity of experimental intracanal pastes based on two glass and glass-ceramic materials. Calcium hydroxide (Ca(OH)2 ) paste was used as the positive control. METHODOLOGY: The glass-ceramic powder [two-phased Biosilicate (BS-2P)] and F18 bioactive glass were mixed with distilled water (ratio 2 : 1), inserted in polyethylene tubes and implanted in the subcutaneous tissues of 16 rats. Empty tubes were used as negative control. After 7 and 30 days (n = 8), the rats were euthanized for haematoxylin-eosin, von Kossa, polarized light and osteopontin (OPN) immunolabeling analysis. Direct contact tests using a suspension of each paste were performed with Enterococcus faecalis planktonic cells to evaluate antimicrobial activity (24 h of contact), in a pilot study. The number of CFU mL-1 was calculated for each group. The antimicrobial analysis data were submitted to one-way anova and Tukey tests, whilst biocompatibility and immunohistochemical data were submitted to the Kruskal-Wallis and Dunn tests (P < 0.05). RESULTS: Most specimens of the control, BS-2P and Ca(OH)2 groups were associated with moderate inflammation seven days following implantation, whilst F18 was associated with moderate to severe inflammation, without differences amongst the groups (P > 0.05). At 30 days, most specimens of control, F18 and BS-2P groups had mild inflammation, whilst Ca(OH)2 had mild to moderate inflammation; however, no differences were determined amongst the groups (P > 0.05). The fibrous capsule was thick at 7 days, becoming thin at 30 days. All pastes induced von Kossa-positive structures and were birefringent to polarized light. At seven days, the BS-2P group had significantly more OPN immunolabeling compared to the control and Ca(OH)2 groups (P < 0.05). At 30 days, the F18 group had significantly more OPN immunolabeling compared to the control and Ca(OH)2 groups (P < 0.05). All pastes reduced the total number of E. faecalis; however, the reduction was only significant when comparing BS-2P and Ca(OH)2 groups to the control (P < 0.05). Only calcium hydroxide eliminated E. faecalis. CONCLUSIONS: Experimental BS-2P and F18 pastes were biocompatible, stimulated biomineralization and induced significant OPN immunolabeling compared to Ca(OH)2 . Only the BS-2P paste demonstrated antimicrobial activity comparable to Ca(OH)2 .


Assuntos
Anti-Infecciosos , Hidróxido de Cálcio , Animais , Hidróxido de Cálcio/farmacologia , Cerâmica , Enterococcus faecalis , Projetos Piloto , Ratos
5.
Int Endod J ; 53(10): 1387-1397, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32573791

RESUMO

AIM: To investigate the relationship between apical periodontitis and atherosclerosis in rats by lipid profile and carotid artery intima tunic measurement, and histological and histometric evaluation of periapical lesions. METHODOLOGY: Forty male Wistar rats were allocated into four groups: control (C), with apical periodontitis (AP), with atherosclerosis (AT) and with AP and AT (AP + AT). Atherosclerosis was induced using a high-lipid diet associated with a surgical ligature in the carotid artery and a super dosage of vitamin D3 . AP was induced via pulp exposure to the oral environment. At 45 and 75 days, serum levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were measured. The maxillary and mandibular jaws and carotid artery were collected and processed for histological analysis. The Kruskal-Wallis or Mann-Whitney test was performed for nonparametric data, and the Tukey's or Student's t-test was performed for parametric data (P < 0.05). RESULTS: In nonatherosclerotic animals, the induction of apical periodontitis increased TG levels significantly, from 63.1 ± 11.4 mg dL-1 in group C to 88.2 ± 7.9 mg dL-1 in the AP group (P < 0.05). The induction of AP was associated with a trend for higher TC and LDL-C levels in atherosclerotic animals (P > 0.05); however, it only significantly increased TG levels, from 93.2 ± 18.0 mg dL-1 in AT group to 121.9 ± 14.5 mg dL-1 in the AP + AT group (P < 0.05). Animals in the AP + AT group had a 36.5% increase in the thickness of the carotid intima tunic when compared with the AT group (P < 0.05). The intensity of the inflammatory infiltrate was significantly larger in the AP + AT group when compared with AP group (P < 0.05). The AP + AT group exhibited significantly greater alveolar bone loss, with a periapical lesion size of 206.4 ± 56.3 × 104 µm2 , compared with 151.4 ± 49.1 × 104 µm2 in the AP group (P < 0.05). CONCLUSION: Apical periodontitis influenced triglyceride levels, increasing them even in the absence of atherosclerosis, and influenced the increase in the thickness of the carotid artery intima tunic in the presence of atherosclerosis. Atherosclerosis intensified the inflammatory reaction and increased bone resorption in periapical lesions.


Assuntos
Aterosclerose , Periodontite Periapical , Animais , Aterosclerose/etiologia , Humanos , Inflamação , Lipídeos , Masculino , Ratos , Ratos Wistar
6.
Int Endod J ; 53(5): 660-670, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31808951

RESUMO

AIM: To evaluate the morphology and impact of root canal preparation in maxillary incisors with palatogingival grooves (PGG). METHODOLOGY: Twenty extracted human maxillary incisors with PGG were subjected to macroscopic analysis and scanning electron microscopy analysis (SEM). The following characteristics of the PGG were evaluated: depth, point of origin in the cingulum, extension and position on the lingual surface. Furthermore, the presence of calculus, communications between the root canal system and the PGG, and root resorptions were investigated. The root canals were subsequently instrumented with K-files of three consecutive sizes. The teeth were sectioned, and the axial plane of each tooth section was imaged using SEM before and after instrumentation. The distance between the root canal walls and the PGG was calculated according to the location. Additionally, the distance between canal walls and cementum was measured at three different sites, to verify if instrumentation influenced dentine removal on a specific wall in teeth with PGG. Statistical analysis was performed using the Mann-Whitney or Student's t-test (P < 0.05). RESULTS: Macroscopic analysis revealed that a deep groove was most frequently observed (75%), followed by a depression/shallow groove (25%) (P < 0.05). PGG typically originated in the distal margin ridge of the cingulum (65%) (P < 0.05), extending only to the middle (45%) or up to the apical (50%) third of the root (P < 0.05). Additionally, PGGs were typically located on the distal aspect of the lingual surface (70%) (P < 0.05). Calculus was concentrated on the surface of the crown and cementum-enamel junction (P < 0.05). Communication between the root canal and PGG was present in 35% of teeth, and root resorptions were noted in 50% of teeth. The distance between the external root surface and the pulp cavity was significantly narrower after instrumentation (P < 0.05); however, root canal preparation did not influence dentine removal on the specific wall associated with the groove (P > 0.05). CONCLUSIONS: Palatogingival grooves were characteristically deep and originated from the distal margin of the cingulum. Although it has been associated with a thinner root wall, root canal preparation did not influence the thickness of the specific wall in the maxillary incisors with PGG.


Assuntos
Cavidade Pulpar , Camada de Esfregaço , Cemento Dentário , Dentina , Humanos , Incisivo , Irrigantes do Canal Radicular , Preparo de Canal Radicular , Tratamento do Canal Radicular
7.
Int Endod J ; 52(12): 1723-1737, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31322737

RESUMO

AIM: To investigate hydrogen peroxide (H2 O2 )-induced responsiveness in pulp cells using heme oxygenase-1 (HO-1) immunolabelling, Jun-D immunolabelling to study the effects of H2 O2 on odontoblastic differentiation and CD90+/CD73+/CD105+/CD45- cell counting for in vivo identification of mesenchymal stem cells in the pulp. METHODOLOGY: The maxillary molars of 50 rats were treated with a bleaching gel (35% H2 O2 , 1 × 30 min) or placebo gel (control groups). At 2, 3, 7, 15 and 30 days after the treatment (n = 10), inflammation in pulp tissue was analysed by haematoxylin-eosin staining, HO-1- and Jun-D-immunolabelled cells were counted in each third of the pulp chamber, and the number of CD90+/CD73+/CD105+/CD45- cells was quantified by immunofluorescence. The results were assessed using the Paired t-test or Wilcoxon signed-rank test (P < 0.05). RESULTS: Significant H2 O2 -induced inflammation was noted at 2 and 3 days (P < 0.05), with tertiary dentine formation occurring from 7 days. The bleached specimens had greater HO-1 immunolabelling in the middle and cervical thirds of the coronal pulp at 2 and 3 days, in all thirds at 7 days, and in the occlusal third at 15 days (P < 0.05), and significant nuclear Jun-D immunolabelling in the cervical third at 2 and 3 days and in the occlusal and middle thirds at 7 days (P < 0.05). Bleached and control groups had low numbers of CD90+/CD73+/CD105+/CD45- cells in the pulp at all periods (P > 0.05). CONCLUSIONS: Pulp cells responded to oxidative stress by expressing HO-1 during the post-bleaching inflammation phase until the beginning of the repair phase. Jun-D expression occurred during the reduction of inflammation and the beginning of tertiary dentine production. The presence of oxidative stress did not influence the number of CD90+/CD73+/CD105+/CD45- cells identified in vivo in the dental pulp.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Polpa Dentária , Heme Oxigenase-1 , Ratos , Ratos Wistar
8.
Int Endod J ; 52(5): 665-675, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30488465

RESUMO

AIM: To analyse the influence of H2 O2 on pulp repair through osteocalcin and osteopontin immunolabelling and in cellular defence by using the antireactive oxygen species (ROS) antibody. METHODOLOGY: The maxillary molars of 50 rats were treated with 35% H2 O2 (Ble groups) or placebo gel (control groups). At 0 h and 2, 7, 15 and 30 days (n = 10 hemimaxillae), the rats were killed and pulp tissue was evaluated using inflammation and immunolabelling scores (osteocalcin/osteopontin); ROS-positive cells were counted. Paired t-test and Wilcoxon signed-rank test were used (P < 0.05). RESULTS: The Ble group had necrosis in the coronal pulp at 0 h and in the occlusal third of the coronal pulp at 2 days; at 7, 15 and 30 days, no inflammation was noted similar to the controls (P > 0.05). Osteocalcin was absent in the Ble at 0 h, moderate at 2 days and increased thereafter, differing from the controls at all two periods (P < 0.05). Osteopontin was higher principally at 7 and 15 days in Ble groups, but differing with control groups from 2 days after bleaching (P < 0.05). The Ble group had more ROS-positive cells in the pulp at 7 and 15 days (P < 0.05). Tertiary dentine was observed at 7 days, increasing thereafter (P < 0.05). CONCLUSIONS: Post-bleaching pulp repair was associated with increased osteocalcin over time. Osteopontin also participated in this process, and anti-ROS was involved in cellular defence against H2 O2 .


Assuntos
Osteopontina , Clareadores Dentários , Animais , Polpa Dentária , Peróxido de Hidrogênio , Osteocalcina , Ratos , Ratos Wistar
9.
Int Endod J ; 52(5): 689-700, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30515845

RESUMO

AIM: To evaluate the inflammatory response and ability to induce mineral deposition through histological and immunohistochemical analysis for osteocalcin (OCN), osteopontin (OPN) and bone sialoprotein (BSP) of a new calcium silicate-based cement, Bio-C Pulpo (Angelus), compared to white mineral trioxide aggregate (White MTA-Ang) (Angelus). METHODOLOGY: Polyethylene tubes containing Bio-C Pulpo and White MTA-Ang as well as empty tubes were implanted into the dorsal connective tissue of 30 Wistar rats, which were arranged in five groups according to the period of analysis: 7, 15, 30, 60 and 90 days. After each experimental period, the tubes with surrounding tissue were removed and histologically processed to be analysed using haematoxylin-eosin and immunohistochemistry for the detection of OCN, OPN and BSP. The data were statistically analysed (Friedman's test) at a 5% significance level. RESULTS: The inflammatory response observed with Bio-C Pulpo and White MTA-Ang was greater after 7 and 15 days and decreased from 30 days onwards. No significant difference was found between the control, Bio-C Pulpo and White MTA-Ang at the different periods of analysis (P > 0.05). The immunolabelling for OCN, OPN and BSP was more intense for Bio-C Pulpo and White MTA-Ang after 60 and 90 days, but there was no difference between Bio-C Pulpo and White MTA-Ang at the different periods of analysis (P > 0.05). CONCLUSION: Bio-C Pulpo is biocompatible and induces immunolabelling of osteogenic markers such as OCN, OPN and BSP similar to White MTA-Ang.


Assuntos
Cálcio , Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Animais , Materiais Biocompatíveis , Compostos de Cálcio , Cimentos Dentários , Combinação de Medicamentos , Óxidos , Ratos , Ratos Wistar , Silicatos
10.
Nanotechnology ; 29(31): 315101, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-29762138

RESUMO

The main limitation of drug-enhanced radiotherapy concerns the difficulty to evaluate the effectiveness of cancer targeting after drug administration hindering the standardization of therapies based on current radiosensitizing compounds. The challenge regards the development of systems able to combine imaging and radiotherapy enhancement in order to perform highly reliable cancer theragnosis. For these reasons, gold-magnetite hybrid nanoparticles (H-NPs) are proposed as innovative theranostic nanotools for imaging-guided radiosensitization in cancer treatment. In this work we propose a novel method for the synthesis of hydrophilic and superparamagnetic Tween20-stabilized gold-magnetite H-NPs. Morphology and chemical composition of nanoparticles were assessed by transmission electron microscopy, x-ray diffraction analysis and ion-coupled plasma optical emission spectroscopy. Colloidal stability and magnetic properties of nanoparticles were determined by dynamic light scattering and magnetometry. The potentialities of H-NPs for magnetic resonance imaging were studied using a human 4T-MRI scanner. Nanoparticles were proven to induce concentration-dependent contrast enhancement in T2*-weighted MR-images. The cytotoxicity, the cellular uptake and the radiosensitization activity of H-NPs were investigated in human osteosarcoma MG63 cell cultures and murine 3T3 fibroblasts, using specific bioassays and laser scanning confocal microscopy. H-NPs did not exhibit significant toxicity and were demonstrated to be internalized by cells. A significant x-ray enhancement at specific H-NPs exposure concentrations was evidenced on MG63 cell line.

11.
Int Endod J ; 51(7): 789-799, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29352770

RESUMO

AIM: To evaluate lymphocyte-like cell activation (CD5-positive cells) and the expression of interleukin (IL)-6 and IL-17 in the pulp after tooth bleaching with two concentrations of hydrogen peroxide (H2 O2 ). METHODOLOGY: The right and left maxillary molars from 40 rats were treated randomly with bleaching gel with 20% H2 O2 (BLUE group, 1 application of 50 min), 35% H2 O2 (MAXX group, three applications of 15 min), or placebo gel (control). After 2 and 30 days, the rats were killed (n = 10), and the jaws were processed for histological and immunohistochemistry analysis of the pulp tissue. The scores of inflammation and immunolabelling (IL-6/IL-17) were submitted to Mann-Whitney and Kruskal-Wallis followed Dunn tests, respectively; anova tests were used for comparisons of number of CD5-positive cells and pulp chamber area values (P < 0.05). RESULTS: At 2 days, 60% of specimens of the BLUE group were associated with moderate inflammation in pulp horns, and in the MAXX group with necrosis (P < 0.05). At 30 days, the pulp was organized, and tertiary dentine was formed. The MAXX group had superior immunolabelling of IL-17 at 2 days differing significantly from other groups (P < 0.05). At 2 days, 90% of the specimens of the BLUE group had moderate immunolabelling of IL-6, and 50% of the MAXX group had severe immunolabelling, both significantly different from the control (P < 0.05). There was no significant difference between the groups at 30 days (P > 0.05). CD5-positive cells were present at 2 and 30 days, particularly in the bleached groups (P < 0.05), without significant difference between time periods (P > 0.05). CONCLUSIONS: IL-6 and IL-17 participated in inflammation in the pulp tissue of rats after tooth bleaching, particularly at 2 days. The immunolabelling was greater with increasing H2 O2 concentration. This process was accompanied by the prolonged activation of CD5-positive cells.


Assuntos
Antígenos CD5/metabolismo , Polpa Dentária/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Clareadores Dentários/farmacologia , Animais , Polpa Dentária/citologia , Polpa Dentária/metabolismo , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Ratos , Ratos Wistar
12.
Int Endod J ; 51(3): 347-356, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28857196

RESUMO

AIM: To evaluate the influence of tooth bleaching on immunoregulatory cytokines production (IL-6, Tumour necrosis factor (TNF)-α and IL-17) in the pulp tissue of normoglycaemic and diabetic rats. METHODOLOGY: Twenty-eight rats were divided into normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with a single dose of alloxan diluted in citrate buffer via intramuscular injection. After DM confirmation, all rats were sedated and tooth bleaching was performed using 35% hydrogen peroxide on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 and 30 days, rats were euthanized and hemimaxillae processed for analysis by haematoxylin and eosin and immunohistochemistry. Results within and between animals were submitted to Wilcoxon signed-rank and Mann-Whitney tests (P < 0.05). RESULTS: At 2 days, the NBle group had mild, and the DBle had severe inflammatory infiltration in the pulpal tissue (P < 0.05). TNF-α and IL-6 cytokines were associated with increased immunolabelling in the bleached groups compared to nonbleached (P < 0.05). However, IL-17 had increased immunolabelling in the NBle compared to the N and DBle group (P < 0.05). At 30 days, reactionary dentine was observed in the coronal pulp of all bleached teeth and no inflammation was present (P > 0.05). TNF-α cytokines had increased immunolabelling in the DBle group compared to the D group (P < 0.05). However, for IL-6 and IL-17, no difference was observed in this period (P > 0.05). CONCLUSIONS: Tooth bleaching increased IL-6 and TNF-α in the pulp tissue regardless of diabetes mellitus; however, diabetic rats had higher TNF-α levels for longer periods. Tooth bleaching influenced the increase in IL-17 in the early periods in normoglycaemic rats.


Assuntos
Polpa Dentária/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Peróxido de Hidrogênio/farmacologia , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Clareadores Dentários/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Polpa Dentária/metabolismo , Masculino , Ratos , Ratos Wistar , Clareamento Dental/métodos
13.
Physiol Behav ; 180: 91-97, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28821446

RESUMO

Obesity is a multifactorial disease characterized by the abnormal or excessive fat accumulation, which is caused by an energy imbalance between consumed and expended calories. Obesity leads to an inflammatory response that may result in peripheral and central metabolic changes, including insulin and leptin resistance. Insulin and leptin resistance have been associated with metabolic and cognitive dysfunctions. Obesity and some neurodegenerative diseases that lead to dementia affect mainly women. However, the effects of diet-induced obesity on memory consolidation in female rats are poorly understood. Therefore, the aim of this study was to evaluate the effect of a hypercaloric diet on the object recognition memory of female rats and on possible related metabolic changes. The animals submitted to the hypercaloric diet presented a higher food intake in grams and in calories, resulting in increased weight gain and liposomatic index in comparison with the animals exposed to the control diet. These animals presented a memory deficit in the object recognition test and increased serum levels of glucose and leptin. However, no significant differences were found in the serum levels of insulin, TNF-α and IL-1ß, in the index of insulin resistance (HOMA), in the hippocampal levels of insulin, TNF-α and IL-1ß, as well as on Akt expression or activation in the hippocampus. Our findings indicate that adult female rats submitted to a hypercaloric diet present memory consolidation impairment, which could be associated with diet-induced weight gain and leptin resistance, even without the development of insulin resistance.


Assuntos
Dieta/efeitos adversos , Consolidação da Memória/fisiologia , Transtornos da Memória/etiologia , Obesidade/complicações , Obesidade/etiologia , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Insulina/metabolismo , Leptina/metabolismo , Lipossomos/metabolismo , Ratos , Ratos Wistar , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
14.
Phys Rev E ; 95(2-1): 022111, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28298009

RESUMO

Systems of particles with long-range interactions present two important processes: first, the formation of out-of-equilibrium quasistationary states (QSS) and, second, the collisional relaxation towards Maxwell-Boltzmann equilibrium in a much longer time scale. In this paper, we study the collisional relaxation in the Hamiltonian mean-field model using the appropriate kinetic equations for a system of N particles at order 1/N: the Landau equation when collective effects are neglected and the Lenard-Balescu equation when they are taken into account. We derive explicit expressions for the diffusion coefficients using both equations for any magnetization, and we obtain analytic expressions for highly clustered configurations. An important conclusion is that in this system collective effects are crucial in order to describe the relaxation dynamics. We compare the diffusion calculated with the kinetic equations with simulations set up to simulate the system with or without collective effects, obtaining a very good agreement between theory and simulations.

15.
Int Endod J ; 50(8): 790-798, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27614116

RESUMO

AIM: To evaluate pulpal tissue response after dental bleaching in normal and alloxan-induced diabetic rats. METHODOLOGY: Twenty-eight rats were divided into two groups of normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with alloxan. After DM confirmation, all rats were anaesthetized and dental bleaching was performed with 35% hydrogen peroxide (H2 O2 ) on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 or 30 days, the animals were euthanized and the hemimaxillae were removed, processed for histopathological analysis and stained with haematoxylin-eosin (HE), Masson's trichrome (MT) and picrosirius red (PSR). Results obtained within animals (normoglycaemic or diabetic rats) were submitted to Wilcoxon or paired t-tests, and between animal (normoglycaemic and diabetic rats), to Mann-Whitney test or t-tests. RESULTS: At 2 days, the NBle group had a mild inflammatory infiltration in the pulpal tissue, whilst the DBle had severe inflammation or necrosis (P < 0.05). At 30 days, no inflammation was present. However, a significant difference in pulp chamber area reduction by reactionary dentine deposition was found between the NBle and DBle groups (P < 0.05). At 2 days, fewer immature collagen fibres and more mature collagen fibres were noted in the NBle, D and DBle groups; this was significantly different when compared to the N group (P < 0.05). At 30 days, significantly fewer immature collagen fibres and more mature collagen fibres were noted in NBle compared with DBle group (P < 0.05). CONCLUSIONS: The inflammatory tissue response in rats' teeth after dental bleaching was greater in diabetic rats. Additionally, the increase in reactionary dentine deposition and mature collagen fibres observed in diabetic rats needs further evaluation to confirm the present results.


Assuntos
Cavidade Pulpar/patologia , Diabetes Mellitus Experimental/fisiopatologia , Peróxido de Hidrogênio/efeitos adversos , Pulpite/induzido quimicamente , Clareadores Dentários/efeitos adversos , Animais , Masculino , Necrose/induzido quimicamente , Ratos Wistar
16.
J Steroid Biochem Mol Biol ; 154: 68-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26200949

RESUMO

Translocator protein (TSPO) is an 18kDa protein located at contact sites between the outer and the inner mitochondrial membrane. Numerous studies have associated TSPO with the translocation of cholesterol across the aqueous mitochondrial intermembrane space and the regulation of steroidogenesis, as well as with the control of some other mitochondrial functions, such as mitochondrial respiration, mitochondrial permeability transition pore opening, apoptosis and cell proliferation. In the brain, changes in TSPO expression occur in several neuropathological conditions including neurodegenerative diseases and psychiatric disorders. Furthermore, TSPO ligands have been shown to promote neuroprotection in animal models of brain pathology. At least in some cases, the mechanisms of neuroprotection are associated with modifications in brain steroidogenesis. In addition, regulation of neuroinflammation seems to be a common mechanism in the neuroprotective actions of TSPO ligands in different animal models of brain pathology.


Assuntos
Modelos Animais de Doenças , Transtornos Mentais/terapia , Doenças Neurodegenerativas/terapia , Receptores de GABA/metabolismo , Animais , Encéfalo/metabolismo , Humanos , Ligantes
17.
J Cardiovasc Surg (Torino) ; 44(3): 319-22, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12832984

RESUMO

The learning curve in off pump surgery must be followed due to the fact that beating heart coronary surgery is a completely different operation. Beating heart coronary surgery is truly a team approach. Both the surgeon and the anesthesiologist must work in concert to attain a smooth, safe and efficient operation. A sternotomy is performed. All conduits are harvested as for traditional coronary artery bypass grafting (CABG). The pericardium is opened using a "hockey stick" incision. Another incision is made to complete the reflection of the pericardium from the pulmonary artery to the aorta. The heart is then repositioned with the surgeon's hand and exposure device is placed at the apex of the heart. Additional pericardial sutures may place for positioning as needed for exposure to complete the other anastomosis using stabilizers. The left internal mammary artery (LIMA) to left anterior descending artery (LAD) graft is performed first, after the postero-lateral wall or the right side of the heart can be revascularized. After each anastomosis is performed, measurement of the flow through the conduit is recommended. The chest is closed in the standard fashion. Off pump coronary artery grafting has been established as a safe and effective procedure. It involves a totally different mind-set for the surgeon. Indication for off pump coronary surgery depends on the experience and comfort level of the surgeon. Currently, there are a multitude of devices available for both exposure and stabilization to efficiently perform this operation. Therefore, most patients should be considered candidates for off pump coronary revascularization.


Assuntos
Ponte Cardiopulmonar , Ponte de Artéria Coronária/métodos , Estenose Coronária/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ponte Cardiopulmonar/educação , Competência Clínica , Ponte de Artéria Coronária/educação , Estenose Coronária/mortalidade , Humanos , Anastomose de Artéria Torácica Interna-Coronária/educação , Anastomose de Artéria Torácica Interna-Coronária/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/educação , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento
18.
J Cardiovasc Surg (Torino) ; 42(6): 709-12, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11698933

RESUMO

BACKGROUND: The use of coronary surgery without cardiopulmonary bypass (CBP) has been growing during the last years. In order to compare myocardial damage during coronary surgery with and without CBP, perioperative Troponin T determinations were done. METHODS: Experimental design and setting: prospective, comparative. Cardiovascular surgery department. Patients, interventions and measures: 29 prospective patients who underwent elective coronary surgery were enrolled. Troponin T determinations (ng/ml) were done before surgical procedure, after a 2-hour and after a 12-hour postoperative. Population was divided in two groups: group 1, with CBP (17 patients); group 2, without CBP (12 patients). Variables in relation with population characteristics, myocardial damage and immediate postoperative haemodynamic results were all analyzed. RESULTS: Population characteristics and basal Troponin levels were similar for the two groups. Troponin T average levels at 2-hour postoperative period was 0.729 ng/ml and 0.067 ng/ml for group 1 and 2, respectively (p<0.00002). At 12 hours postoperative period Troponin T was 1.047 ng/ml and 0.183 ng/ml for group land 2 (p<0.0002). Haemodynamic performance was better in the group without CBP. CONCLUSIONS: Troponin T levels were significantly elevated in group 1, showing that surgical procedures without CBP caused less myocardial damage.


Assuntos
Ponte Cardiopulmonar , Traumatismo por Reperfusão Miocárdica/sangue , Troponina T/sangue , Biomarcadores/sangue , Creatina Quinase/sangue , Creatina Quinase Forma MB , Feminino , Hemodinâmica , Humanos , Cuidados Intraoperatórios , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
19.
Heart Lung Circ ; 10(2): A24-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-16352030
20.
Rev Inst Med Trop Sao Paulo ; 43(6): 303-10, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11781598

RESUMO

The aim of the present study was to determine biological characteristics such as expression of fimbriae, Congo red binding, production of hemolysin and aerobactin, adhesion to HeLa and uroepithelial cells and invasion of HeLa cells by Escherichia coli isolates obtained from patients showing clinical signs of urinary tract infection (UTI). Also, the presence of genes (apa, afa, spa) for fimbria expression and cytotoxic necrotizing factors (CNF1, CNF2) was assayed using specific primers in PCR. The data obtained were compared with the clonal relationships obtained by analysis of multilocus enzyme electrophoresis (MLEE), restriction fragment length polymorphism (RFLP) of the rDNA (ribotyping) and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR). All isolates but one presented a combination of at least two of the characteristics studied, a fact suggesting the presence of pathogenicity islands (PAIs). Diffuse adherence type to HeLa cells was observed to occur in most of the strains, but adhesion to uroepithelial cells seems to be a more reliable test to verify pathogenicity. Although four strains seemed to be able to invade HeLa cells when assayed by light microscopy, electron microscopy studies demonstrated that these strains were not invasive. MLEE, RFLP and ERIC-PCR were able to group the isolates differently into main clusters that were not correlated with the presence of pathogenic traits.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/fisiologia , Infecções Urinárias/microbiologia , Aderência Bacteriana/fisiologia , Eletroforese em Gel de Ágar , Escherichia coli/genética , Escherichia coli/patogenicidade , Células HeLa/microbiologia , Humanos , Reação em Cadeia da Polimerase , Ribotipagem , Virulência
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