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1.
Acta Anaesthesiol Scand ; 61(7): 740-748, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28620916

RESUMEN

BACKGROUND: Ketamine has been used as part of the multimodal analgesia technique in the acute perioperative period. The effect of perioperative intravenous small-dose ketamine on the quality of recovery from the patient point-of-view has not been assessed. We hypothesized that low-dose ketamine would enhance recovery following laparoscopic cholecystectomy under total intravenous anesthesia. METHODS: One hundred thirty five patients undergoing laparoscopic cholecystectomy were enrolled in this randomized, double-blind placebo-controlled trial. Subjects were randomly assigned to one of three groups: saline, ketamine 0.2 mg/kg, or ketamine 0.4 mg/kg immediately following the induction of anesthesia and before skin incision. The primary endpoint was assessed using the Quality of Recovery Questionnaire (QoR-40), a 40-item quality of recovery scoring system. In addition, early clinical recovery variables, such as time to eye opening, occurrence of nausea and vomiting, pain score, analgesic use, and length of PACU stay were assessed. RESULTS: No differences were detected in the total or individual dimension scores of the QoR-40 questionnaire. The incidence of nausea, vomiting, and other complications did not differ among the three groups. CONCLUSIONS: Small doses of ketamine do not improve the quality of recovery after remifentanil-based anesthesia for laparoscopic cholecystectomy.


Asunto(s)
Anestésicos Disociativos , Colecistectomía Laparoscópica , Ketamina , Satisfacción del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Adulto , Analgesia/estadística & datos numéricos , Periodo de Recuperación de la Anestesia , Brasil , Método Doble Ciego , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Cloruro de Sodio , Encuestas y Cuestionarios
2.
Osteoporos Int ; 27(10): 2913-33, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27145947

RESUMEN

UNLABELLED: This systematic review and meta-analysis of randomized controlled trials (RCTs) identified significant effects of whole body vibration (WBV) on bone mineral density (BMD) of the lumbar spine (in the sensitivity analysis and seven subgroup analyses), femoral neck (in one subgroup analysis), and trochanter (four subgroup analyses) in postmenopausal women, but not other measurements of BMD. INTRODUCTION: Interventions using WBV training have been conducted in postmenopausal women, aimed at increasing BMD; however, the results are contradictory. Our objective is to conduct a systematic review and meta-analysis of RCTs examining WBV effect on BMD. METHODS: RCTs were considered eligible, with follow-up ≥6 months, which verified the effects of WBV on the BMD of postmenopausal women. The calculations of the meta-analysis were performed through the weighted mean difference between the WBV and control groups, or the WBV and combined training, through the absolute change between pre- and post-intervention in the areal bone mineral density (aBMD) or trabecular volumetric bone mineral density (vBMDt). RESULTS: Fifteen RCTs were included in the meta-analysis. No differences were observed in the primary analysis. WBV was found to improve aBMD compared with the control group, after exclusion of studies with low quality methodological (lumbar spine), when excluding the studies which combined WBV with medication or combined training (lumbar spine), with the use of low frequency and high magnitude (lumbar spine and trochanter), high frequency and low magnitude (lumbar spine), high cumulative dose and low magnitude (lumbar spine), low cumulative dose and high magnitude (lumbar spine and trochanter), with semi-flexed knee (lumbar spine, femoral neck, and trochanter), and side-alternating type of vibration (lumbar spine and trochanter). CONCLUSIONS: Despite WBV presenting potential to act as a coadjuvant in the prevention or treatment of osteoporosis, especially for aBMD of the lumbar spine, the ideal intervention is not yet clear. Our subgroup analyses helped to demonstrate the various factors which appear to influence the effects of WBV on BMD, contributing to clinical practice and the definition of protocols for future interventions.


Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica/prevención & control , Vibración , Femenino , Cuello Femoral , Humanos , Vértebras Lumbares , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Genet Mol Res ; 15(2)2016 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-27421014

RESUMEN

Hemoglobin (Hb) variants involving alpha-chains are less common in the global population than Hb variants resulting from beta-chain alterations. Generally, alpha-chain Hb variants are caused by point mutations affecting alpha-1 and/or alpha-2 genes of the alpha-globin cluster (HBA1 and HBA2). In Brazil, the most prevalent alpha-chain Hb variant is Hb Hasharon. In this study, we present the first case of an Hb Val de Marne variant in the Americas, specifically in Brazil.


Asunto(s)
Hemoglobinas Anormales/genética , Adulto , Sustitución de Aminoácidos , Brasil , Femenino , Genética de Población , Genotipo , Hemoglobinas Anormales/metabolismo , Humanos , Mutación , Mutación Puntual
4.
Braz J Biol ; 83: e270262, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37075429

RESUMEN

Considered the economic engine of many countries, the coffee culture represents an important component of the agricultural chain in Brazil. The growing values of commercialization, planting areas, and crop productivity require the acquisition of quality seedlings, which must receive adequate nutritional support through efficient fertilizers. Slow and controlled-release fertilizers, such as organominerals, gain prominence when it comes to increasing efficiency in the use of phosphorus, as well as plant growth-promoting bacteria (PGPB) with phosphate solubilizing characteristics. This study aimed to evaluate the effect of different sources of mineral and organomineral fertilizers, inoculated and non-inoculated with PGPB on the quality parameters of coffee seedlings. In general, the P sources used in the experiment positively interfered with the development of coffee seedlings. This proves that there is a need for nutritional supplementation for the good development of the seedlings. Among the sources used, the organomineral in granulated form showed better performance in coffee seedlings' growth and physiological parameters, proving to be a viable alternative to commonly used fertilizers. The addition of PGPB showed a significant advantage for seedling quality variables.


Asunto(s)
Fósforo , Plantones , Fósforo/análisis , Café , Fertilizantes/análisis , Bacterias
5.
Braz J Med Biol Res ; 55: e12343, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36477953

RESUMEN

Adipose tissue-derived mesenchymal stromal/stem cells (ASCs) are considered important tools in regenerative medicine and are being tested in several clinical studies. Porcine models are frequently used to obtain adipose tissue, due to the abundance of material and because they have immunological and physiological similarities with humans. However, it is essential to understand the effects and safe application of ASCs from pigs (pASCs) as an alternative therapy for diseases. Although minipigs are easy-to-handle animals that require less food and space, acquiring and maintaining them in a bioterium can be costly. Thus, we present a protocol for the isolation and proliferation of ASCs isolated from adipose tissue of farm pigs. Adipose tissue samples were extracted from the abdominal region of the animals. Because the pigs were not raised in a controlled environment, such as a bioterium, it was necessary to carry out rigorous procedures for disinfection. After this procedure, cells were isolated by mechanical dissociation and enzymatic digestion. A proliferation curve was performed and used to calculate the doubling time of the population. The characterization of pASCs was performed by immunophenotyping and cell differentiation in osteogenic and adipogenic lineages. The described method was efficient for the isolation and cultivation of pASCs, maintaining cellular attributes, such as surface antigens and multipotential differentiation during in vitro proliferation. This protocol presents the isolation and cultivation of ASCs from farm pig as an alternative for the isolation and cultivation of ASCs from minipigs, which require strictly controlled maintenance conditions and a more expensive process.


Asunto(s)
Tejido Adiposo , Células Madre , Humanos , Porcinos , Animales , Porcinos Enanos
6.
Front Physiol ; 13: 906110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35846002

RESUMEN

Lately, the use of zebrafish has gained increased interest in the scientific community as an animal model in preclinical research. However, there is a lack of in vivo imaging tools that ensure animal welfare during acquisition procedures. The use of functional imaging techniques, like Positron Emission Tomography (PET), in zebrafish is limited since it requires the animal to be alive, representing a higher instrumentation complexity when compared to morphological imaging systems. In the present work, a new zebrafish enclosure was developed to acquire in vivo images while monitoring the animal's welfare through its heartbeat. The temperature, dissolved oxygen, and pH range in a closed aquatic environment were tested to ensure that the conditions stay suitable for animal welfare during image acquisitions. The developed system, based on an enclosure with a bed and heartbeat sensors, was tested under controlled conditions in anesthetized fishes. Since the anesthetized zebrafish do not affect the water quality over time, there is no need to incorporate water circulation for the expected time of PET exams (about 30 min). The range of values obtained for the zebrafish heart rate was 88-127 bpm. The developed system has shown promising results regarding the zebrafish's heart rate while keeping the fish still during the long imaging exams. The zebrafish enclosure ensures the animal's well-being during the acquisition of in vivo images in different modalities (PET, Computer Tomography, Magnetic Resonance Imaging), contributing substantially to the preclinical research.

7.
Colloids Surf B Biointerfaces ; 149: 89-96, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27736726

RESUMEN

Ceramides constitute a group of lipids with usually high melting temperature that also favor negative curvature in membranes when mixed with other lipids. The short chain C10:0 ceramide is an asymmetric lipid which consists of an 18 carbon sphingosine base N-acylated with decanoic acid. According to high sensitivity differential scanning calorimetry, it shows a minor exothermic peak at 61°C and a main endothermic transition at 75°C. By small angle X-ray scattering and polarized light microscopy we found that, at temperatures below the main transition, the fully hydrated lipid dispersions are arranged in a tridimensional structure corresponding to an inverted hexagonal phase. Infrared spectroscopy and wide angle X-ray diffraction indicated that the acyl chains of ceramides exhibit a relatively high order in the hexagonal phase. As far as we know, this is the first report of a lipid hexagonal phase having highly ordered acyl chains. Molecular asymmetry due to the different length of the sphingosine and the N-acyl chains of C10:0 ceramide may explain why this novel phase is formed.


Asunto(s)
Ceramidas/química , Ácidos Decanoicos/química , Acilación , Conformación de Carbohidratos , Transición de Fase , Soluciones , Temperatura , Termodinámica
8.
Braz. j. med. biol. res ; 55: e12343, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1403900

RESUMEN

Adipose tissue-derived mesenchymal stromal/stem cells (ASCs) are considered important tools in regenerative medicine and are being tested in several clinical studies. Porcine models are frequently used to obtain adipose tissue, due to the abundance of material and because they have immunological and physiological similarities with humans. However, it is essential to understand the effects and safe application of ASCs from pigs (pASCs) as an alternative therapy for diseases. Although minipigs are easy-to-handle animals that require less food and space, acquiring and maintaining them in a bioterium can be costly. Thus, we present a protocol for the isolation and proliferation of ASCs isolated from adipose tissue of farm pigs. Adipose tissue samples were extracted from the abdominal region of the animals. Because the pigs were not raised in a controlled environment, such as a bioterium, it was necessary to carry out rigorous procedures for disinfection. After this procedure, cells were isolated by mechanical dissociation and enzymatic digestion. A proliferation curve was performed and used to calculate the doubling time of the population. The characterization of pASCs was performed by immunophenotyping and cell differentiation in osteogenic and adipogenic lineages. The described method was efficient for the isolation and cultivation of pASCs, maintaining cellular attributes, such as surface antigens and multipotential differentiation during in vitro proliferation. This protocol presents the isolation and cultivation of ASCs from farm pig as an alternative for the isolation and cultivation of ASCs from minipigs, which require strictly controlled maintenance conditions and a more expensive process.

9.
Biochim Biophys Acta ; 1668(1): 75-86, 2005 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-15670733

RESUMEN

Solvent solubilized myelin membranes spread as monomolecular layers at the air-water interface show a heterogeneous pattern at all surface pressures. In order to asses the role of myelin protein and lipid components in the surface structuring we compared the topography, as seen by Brewster angle microscopy (BAM) and epifluorescence microscopy, of monolayers made from mixtures containing all myelin lipids (except gangliosides) and variable proportions of Folch-Lees proteolipid protein (PLP, the major protein component of myelin). The presence of the single PLP, in the absence of the other myelin proteins, can reproduce the surface pattern of the whole myelin extract films in a concentration-dependant manner. Moreover, a threshold mole fraction of PLP is necessary to induce the lipid-protein component reorganization leading to the appearance of a rigid (gray) phase, acting as a surface skeleton, at low surface pressures and of fractal clusters at high surface pressures. The average size of those clusters is also dependent on the PLP content in the monolayer and on the time elapsed from the moment of film spreading, as they apparently result from an irreversible lateral aggregation process. The transverse rearrangement of the monolayer occurring under compression was different in films with the highest and lowest PLP mole fractions tested.


Asunto(s)
Proteína Proteolipídica de la Mielina/química , Proteína Proteolipídica de la Mielina/metabolismo , Vaina de Mielina/química , Vaina de Mielina/metabolismo , Animales , Bovinos , Fluorescencia , Microscopía
10.
J Colloid Interface Sci ; 464: 264-76, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26624532

RESUMEN

The molecular packing, thermodynamics and surface topography of binary Langmuir monolayers of Insulin and DPPC (dipalmitoylphosphatidylcholine) or POCP (1-palmitoyl-2-oleoylphosphatidylcholine) at the air/water interface on Zn(2+) containing solutions were studied. Miscibility and interactions were ascertained by the variation of surface pressure-mean molecular area isotherms, surface compressional modulus and surface (dipole) potential with the film composition. Brewster Angle Microscopy was used to visualize the surface topography of the monolayers. Below 20mN/m Insulin forms stable homogenous films with DPPC and POPC at all mole fractions studied (except for films with XINS=0.05 at 10mN/m where domain coexistence was observed). Above 20mN/m, a segregation process between mixed phases occurred in all monolayers without squeezing out of individual components. Under compression the films exhibit formation of a viscoelastic or kinetically trapped organization leading to considerable composition-dependent hysteresis under expansion that occurs with entropic-enthalpic compensation. The spontaneously unfavorable interactions of Insulin with DPPC are driven by favorable enthalpy that is overcome by unfavorable entropic ordering; in films with POPC both the enthalpic and entropic effects are unfavorable. The surface topography reveals domain coexistence at relatively high pressure showing a striped appearance. The interactions of Insulin with two major membrane phospholipids induces composition-dependent and long-range changes of the surface organization that ought to be considered in the context of the information-transducing capabilities of the hormone for cell functioning.


Asunto(s)
1,2-Dipalmitoilfosfatidilcolina/química , Aire , Insulina/química , Fosfatidilcolinas/química , Termodinámica , Agua/química , Tamaño de la Partícula , Propiedades de Superficie
11.
Food Chem Toxicol ; 95: 211-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27394655

RESUMEN

Losartan potassium is an antihypertensive drug in the angiotensin II receptor antagonist (ARA) class. Some studies claim that, in addition to regulating blood pressure, this class of drug has anticancer properties. The objective of this study was to evaluate the genotoxic and antigenotoxic potential of losartan potassium using the SMART (Somatic Mutation and Recombination Test) assay on the somatic cells of Drosophila melanogaster, as well as the possible modulating effects of this drug, when associated with doxorubicin (DXR). Third instar larvae, descendents of standard and high bioactivation (ST and HB) crosses, were chronically treated with different concentrations of losartan potassium (0.25; 0.5; 1; 2; and 4 mM) alone or in association (co-treatment) with doxorubicin (DXR 0.125 mg/mL). The results showed an absence of a mutagenic effect of losartan potassium. In the co-treatment of losartan with DXR, the results showed that losartan is capable of reducing the number of mutant spots induced by DXR without altering the recombinogenic effect of the chemotherapeutic agent. Antiproliferative action appears to be the main mechanism involved in reducing the frequency of mutant spots and consequent modulation of alterations induced by DXR, although this parameter has not been directly assessed in this study.


Asunto(s)
Antibióticos Antineoplásicos/toxicidad , Daño del ADN/efectos de los fármacos , Doxorrubicina/toxicidad , Drosophila melanogaster/efectos de los fármacos , Losartán/farmacología , Mutagénesis/efectos de los fármacos , Recombinación Genética/efectos de los fármacos , Animales , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Pruebas de Mutagenicidad , Alas de Animales/efectos de los fármacos , Alas de Animales/crecimiento & desarrollo
12.
Food Chem Toxicol ; 90: 10-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26829615

RESUMEN

Simvastatin is an antilipemic drug that promotes inhibition of HMG-CoA reductase. Simvastatin can also inhibit the formation of other products, such as isoprenoids, conferring additional benefits to this drug, which include antiproliferative, anti-invasive and pro-apoptotic effects. This study was carried out with the aim of evaluating the mutagenic/recombinogenic effect of simvastatin as well as the possible modulatory effects of this statin on the DNA damage induced by doxorubicin (DXR). This analysis was performed using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. To study these effects, larvae descendants of both crosses (ST and HB) were chronically treated with five concentrations of simvastatin, separately and in association with DXR. The results revealed no mutagenic/recombinogenic effect of simvastatin for any of the concentrations tested. A modulating effect of simvastatin was also observed on DNA damage induced by DXR. The reduction of total mutant frequency was observed for spots from descendants of both crosses, but the inhibition was more effective in descendants from the standard cross (ST). It is believed that this modulating effect is mainly associated with the antioxidant activity of this class of drugs, although this parameter has not been directly assessed in this study.


Asunto(s)
Antibióticos Antineoplásicos/toxicidad , Daño del ADN/efectos de los fármacos , Doxorrubicina/toxicidad , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Simvastatina/farmacología , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Drosophila melanogaster , Estructura Molecular , Simvastatina/administración & dosificación , Simvastatina/química
13.
Biochim Biophys Acta ; 1370(1): 127-37, 1998 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-9518579

RESUMEN

Myelin can be spread as a stable monomolecular layer, with reproducible properties, at the air-water interface. The major lipids and proteins of myelin are represented in this monolayer in molar ratios similar to those in the original membrane. A well-defined collapse point of the myelin monolayer occurs at ca. 46 mN/m. At a surface pressure of ca. 20 mN/m, the surface pressure-molecular area isotherm of the myelin monolayer shows a change in its compressibility, exhibited as a diffuse but reproducible inflection with a clearly marked change of the surface compressional modulus; the surface potential-area curve shows a change of slope at the same surface pressure. The myelin monolayer shows considerable hysteresis during the first compression-decompression cycle; no detectable protein unfolding under expansion; and decreased hysteresis after the first cycle. The average molecular areas, the inflection at 20 mN/m, the variation of the surface potential per unit of molecular surface density, and the hysteresis properties of the myelin monolayer indicate that this membrane undergoes changes of intermolecular organization mostly ascribed to the protein fraction, above a lateral surface pressure of ca. 20 mN/m. The behavior is consistent with a surface pressure-dependent relocation of protein components in the film. This has marked effects on the stability, molecular packing, and dipolar organization of the myelin interface.


Asunto(s)
Lípidos de la Membrana/química , Vaina de Mielina/química , Animales , Bovinos , Fuerza Compresiva , Cinética , Proteínas de la Mielina/química , Médula Espinal/química , Propiedades de Superficie , Termodinámica
14.
Food Chem Toxicol ; 81: 111-119, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25846503

RESUMEN

The competitive inhibitors of HMG-CoA reductase, popularly known as statins, exert pleiotropic effects, which result from the ability of statins to inhibit the synthesis of isoprenoids, which are fundamental for the functioning of proteins responsible for intracellular signaling. Some recent studies suggest an important role associated with the use of antineoplastic atorvastatin and rosuvastatin, the statins most widely used today. In this study, the Drosophila wing spot test was used to evaluate possible protective effects of atorvastatin and rosuvastatin against damage induced by DXR. Larvae were chronically treated with negative control (ethanol 5%), positive control (DXR 0.125 mg/mL) and five different concentrations of atorvastatin and rosuvastatin. The results demonstrated absence of a mutagenic effect for the two statins tested. The analysis of the descendants co-treated with DXR and atorvastatin/rosuvastatin revealed a modulatory effect of these statins on damage induced by DXR. This effect was verified in all concentrations tested in the descendants of the ST and HB crosses treated with rosuvastatin, and only in descendants of the HB cross treated with atorvastatin. Induction of apoptosis and antioxidant activity appear to be the main mechanisms involved in reducing the frequency of mutant spots and consequent modulation of the damage induced by DXR.


Asunto(s)
Atorvastatina/farmacología , Doxorrubicina/toxicidad , Drosophila melanogaster/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Rosuvastatina Cálcica/farmacología , Animales , Daño del ADN/efectos de los fármacos , Femenino , Larva/efectos de los fármacos , Masculino , Pruebas de Mutagenicidad , Alas de Animales/efectos de los fármacos
15.
Int J Pediatr Otorhinolaryngol ; 61(3): 223-32, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11700192

RESUMEN

OBJECTIVE: The first epidemiological study carried out in Latin America to investigate the prevalence of otological disease and its impact in a representative random sample of the school children population. METHODS: A cross sectional epidemiological survey to investigate the epidemiology of otitis in a representative random sample of 1119 children and adolescents from a total of 486166 elementary and high-school students, aged 6-18 years, regularly registered in one of the 521 public and private schools of the city of Belo Horizonte, in the state of Minas Gerais, southern Brazil. The interviews were conducted individually, in the school, by an otolaryngologist or a pediatrician. The interview included all of the personal data and also detailed questions regarding otological disorders and hearing. The otological examination was carried out with Mini-Heine otoscopes and the audiometric evaluation with the AudioScope 3 with 25dB intensity. The questionnaire and basic procedures for medical examination had been previously tested through a pilot test in two schools. RESULTS: The prevalence of chronic otitis media was 0.94%. Impacted wax was found in 12.3% of the students. The prevalence of abnormalities (excluding wax) in the otoscopy examination was 10.5%. It was found that 8.3% of students had a past history of otitis and 7.7% had a past history of otorrhea. These two special groups presented statistically significant associations with chronic otitis media, hearing loss and otolaryngological surgeries (when compared with the other school children). Parents and school children seemed significantly able to identify a special group of children with past history of otitis during childhood.


Asunto(s)
Otitis Media/epidemiología , Perfil de Impacto de Enfermedad , Adolescente , Brasil/epidemiología , Cerumen , Niño , Enfermedad Crónica , Estudios Epidemiológicos , Femenino , Trastornos de la Audición/epidemiología , Trastornos de la Audición/patología , Pruebas Auditivas , Humanos , América Latina/epidemiología , Masculino , Otitis Media/patología , Prevalencia , Distribución Aleatoria
16.
Photomed Laser Surg ; 22(6): 533-6, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15684757

RESUMEN

OBJECTIVE: This study evaluated the dentinal and marginal permeability of the cut surface after apicoectomy, treatment and retrocavity preparation with Er:YAG and Nd:YAG lasers. Furthermore, scanning electron microscopy (SEM) analysed the morphological alteration of dentin caused by laser irradiation through an optical fiber. BACKGROUND DATA: Numerous studies have shown the beneficial effects of laser treatment upon sealing dental apex, avoiding the changes of organic fluids, microorganisms and their by-products between the root canal system and periapex. MATERIALS AND METHODS: Twenty-four extracted and endodontically treated teeth were divided into three groups: GI, apices were resected with Er:YAG laser (350 mJ; 4 Hz) treatment of cut dentinal surface and retrocavity were lased with this same laser (120 mJ; 4 Hz; bur 2051) using the optical fiber 50/10; GII, apicoectomy was performed similar to GI, however the cut dentinal surface was treated with Nd:YAG laser through optical fiber, as well as the retrocavity preparation (100 mJ; 15 Hz; 1.5 W); and GIII (control group), high speed burs were used. RESULTS: Analysis of methylene blue dye penetration into dentin demonstrated that the specimens of the groups irradiated with laser showed to have lower infiltration indices than the control group. These results were compatible with structural and morphological injuries, evidenced by SEM. CONCLUSION: Under the conditions of the present study, apicoectomy using Er:YAG laser, followed by dentinal surface irradiation and retrocavity preparation with Nd:YAG laser, showed to be an alternative clinical tool able to reduce the dentinal permeability.


Asunto(s)
Rayos Láser , Diente/efectos de la radiación , Humanos , Microscopía Electrónica de Rastreo
17.
Colloids Surf B Biointerfaces ; 115: 219-28, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24362061

RESUMEN

The interfacial behavior of regular insulin (Reg-insulin) and aspart insulin (Asp-insulin) was critically affected by the presence of Zn(2+) in the subphase. This cation induced a condensed-like behavior in the compression isotherms, especially apparent for Reg-insulin films when observed by Brewster angle microscopy. Immediately after spreading, Reg-insulin, but not Asp-insulin, showed bright patches that moved in a gaseous-like state. Moreover, Zn(2+) caused marked variations of the surface electrostatics of both insulin monolayers and considerable hysteresis of their molecular organization. By oscillatory compression-expansion cycles, we observed in all cases the development of a dilatational response to the surface perturbation, and both monolayers exhibited well-defined shear moduli in the presence of Zn(2+), which was higher for Reg-insulin. Development of a shear modulus indicates behavior resembling a nominal solid, more apparent for Reg-insulin than for Asp-insulin, suggesting the presence of viscoelastic networks at the surface.


Asunto(s)
Aire , Insulina Aspart/química , Insulina/química , Reología , Agua/química , Zinc/química , Fuerza Compresiva , Módulo de Elasticidad , Humanos , Presión , Propiedades de Superficie , Termodinámica , Viscosidad
18.
Arq. bras. med. vet. zootec. (Online) ; 71(4): 1293-1298, jul.-ago. 2019. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1038619

RESUMEN

The pelvimetry consists of the metric determination of the pelvis dimensions and its use is directly related to the reproduction. The cartilage closure time of the ossification centers varies according to the bone, some closing already in the uterine life and others remaining present for many years. The objective was to evaluate, radiographically, the pelvic diameters by pelvimetry during the first 24 months of life in pacas, the second lagest Brazilian rodent and an animal that has shown big recent scientific interest, aiming the estimated age determination. Twelve pacas were used, which were monthly radiographed up from birth until 24 months old, with the animals anesthetized. The pacas are dolicopelvic animals and with pelvis presenting strong tendency to constant growth along the 12 first months of age, fact that can be useful in the approximated animals' age determination that do not have precise birth date, for example.(AU)


A pelvimetria consiste na determinação métrica das dimensões pélvicas, e sua utilização está diretamente relacionada à reprodução. O momento de fechamento da cartilagem dos centros de ossificação varia de acordo com o osso, algumas fechando já na vida uterina e outras permanecendo presentes por vários anos. Objetivou-se avaliar, radiograficamente, os diâmetros pélvicos, mediante pelvimetria, durante os 24 primeiros meses de vida de pacas, o segundo maior roedor brasileiro e sobre o qual tem havido grande interesse científico, para a determinação aproximada da idade. Foram utilizadas 12 pacas, as quais foram radiografadas mensalmente a partir do nascimento até 24 meses de idade, com os animais anestesiados. As pacas são animais dolicopélvicos e com pelve apresentando forte tendência ao crescimento constante durante os 12 primeiros meses de vida, o que pode ser útil na determinação aproximada da idade em animais que não possuem data precisa de nascimento, por exemplo.(AU)


Asunto(s)
Animales , Pelvis/anatomía & histología , Pelvis/diagnóstico por imagen , Pesos y Medidas Corporales/veterinaria , Cuniculidae , Pelvimetría/veterinaria
19.
Colloids Surf B Biointerfaces ; 107: 59-67, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23466543

RESUMEN

Neurons are highly polarized cells, composed of one axon and several branching dendrites. One important issue in neurobiology is to understand the molecular factors that determine the neuron to develop polarized structures. A particularly early event, in neurons still lacking a discernible axon, is the segregation of IGF-1 (Insulin like Growth Factor-1) receptors in one neurite. This receptor can be activated by insulin in bulk, but, it is not known if changes of insulin organization as a monomolecular film may affect neuron polarization. To this end, in this work we developed solid-supported Langmuir-Blodgett films of insulin with different surface packing density. Hyppocampal pyramidal neurons, in early stage of differentiation, were cultured onto those substrates and polarization was studied after 24 h by confocal microscopy. Also we used surface reflection interference contrast microscopy and confocal microscopy to study attachment patterns and morphology of growth cones. We observed that insulin films packed at 14 mN/m induced polarization in a similar manner to high insulin concentration in bulk, but insulin packed at 44 mN/m did not induce polarization. Our results provide novel evidence that the neuron polarization through IGF-1 receptor activation can be selectively modulated by the lateral packing of insulin organized as a monomolecular surface for cell growth.


Asunto(s)
Polaridad Celular/efectos de los fármacos , Insulina/farmacología , Neuronas/citología , Animales , Bovinos , Adhesión Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Cloruros/farmacología , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Conos de Crecimiento/efectos de los fármacos , Conos de Crecimiento/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Polilisina/farmacología , Ratas , Receptor IGF Tipo 1/metabolismo , Propiedades de Superficie , Compuestos de Zinc/farmacología
20.
Food Chem Toxicol ; 50(8): 2598-604, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22621838

RESUMEN

In this study the mutagenic, recombinagenic, carcinogenic and anticarcinogenic potential of orlistat was assessed using the somatic mutation and recombination test (SMART) and the epithelial tumor detection test (wts). The experiments were conducted on Drosophila melanogaster. In the assessment using SMART, larvae, descendants from the standard (ST) cross and the high bioactivation (HB) cross, were treated chronically with three orlistat concentrations. The results revealed a recombinagenic effect, associated with orlistat, in the descendants of the HB cross, at all three levels of concentration. Homologous recombination can function as a determinant at different stages of carcinogenesis. For verification, larvae from the wts test, descendants of the wts/TM3 virgin female and mwh/mwh male cross, were treated with the same three orlistat concentrations separately and in association with mitomicin C (0.1mM). The results did not, however, provide evidence that orlistat has carcinogenic potential nor was it associated with the reduction of tumors induced by mitomicin C in D. melanogaster.


Asunto(s)
Fármacos Antiobesidad/toxicidad , Carcinógenos/toxicidad , Lactonas/toxicidad , Mutágenos/toxicidad , Recombinación Genética/efectos de los fármacos , Animales , Drosophila melanogaster , Orlistat
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