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1.
Reumatismo ; 74(3)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36580066

RESUMO

Takayasu arteritis (TA) is an extremely uncommon vasculitis that primarily affects the aorta and its branches. Due to the genetic and ethnicity effect, a diverse array of TA clinical manifestations has been reported worldwide. The purpose of the present study was to compare the clinicodemographic characteristics and pattern of vascular involvement of Iranian and Turkish TA patients. This study was a retrospective, cross-sectional investigation of 126 TA patients in Iran and Turkey. All of the variables analyzed were extracted from historical medical records. In 126 TA patients, the ratio of females to males was 8.6:1, and the average age at onset of disease was 30.5±11.1 years. Fatigue (49.2%) and a weak or absent pulse (79.4%) were the most prevalent symptoms and signs, respectively. The most prevalent angiographic classifications were types V and I in Iranian patients (41.09%) and type I in the Turkish population (47.7%) The left subclavian artery was the vessel most frequently affected by TA (66.6%). Our findings indicated that there were no significant differences between the two countries in terms of clinicodemographic characteristics or vascular involvement. Some clinical manifestations, such as claudication, were more prevalent in the Turkish population due to a higher incidence of occlusive lesions in the right subclavian artery.


Assuntos
Arterite de Takayasu , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Arterite de Takayasu/complicações , Arterite de Takayasu/diagnóstico por imagem , Arterite de Takayasu/epidemiologia , Estudos Retrospectivos , Irã (Geográfico)/epidemiologia , Turquia/epidemiologia , Estudos Transversais
2.
Int Endod J ; 51 Suppl 3: e238-e249, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28881396

RESUMO

AIM: To identify guidelines on endodontics which make recommendations relating to post-root canal treatment radiological review imaging, to make an objective assessment of their quality using the AGREE tool and to examine the evidence cited in support of their recommendations. METHODOLOGY: The primary sources to identify published guidelines were MEDLINE (Ovid® ) and EMBASE. The search aim was to identify guidelines pertaining to the post-root canal treatment follow-up recommendations published from 1946 with the final search date being 26 June 2016. The primary search was supplemented by searching Internet search engines and several websites that might have guidelines. The guidelines obtained from the search end-result were assessed for quality and scientific evidence using the AGREE II instrument. Similarities and differences in the recommendations were identified. RESULTS: Thirty guidelines were identified, seven of which met the inclusion criteria. Two guidelines used and clearly described the methods for obtaining scientific evidence from which the recommendations were set. The recommendations varied, particularly as regards the timing of the first review radiograph. Some guidelines lacked supporting evidence. CONCLUSIONS: The recommendations for post-root canal treatment radiographic follow-up varied amongst the identified guidelines. However, the methodology for obtaining the scientific evidence was poorly described in most of the guidelines. Guideline development groups should use the AGREE II instrument as a guide to produce higher quality guidelines.


Assuntos
Cavidade Pulpar/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Tratamento do Canal Radicular , Humanos
3.
PLoS Genet ; 10(4): e1004235, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24699409

RESUMO

Variants in the growth factor receptor-bound protein 10 (GRB10) gene were in a GWAS meta-analysis associated with reduced glucose-stimulated insulin secretion and increased risk of type 2 diabetes (T2D) if inherited from the father, but inexplicably reduced fasting glucose when inherited from the mother. GRB10 is a negative regulator of insulin signaling and imprinted in a parent-of-origin fashion in different tissues. GRB10 knock-down in human pancreatic islets showed reduced insulin and glucagon secretion, which together with changes in insulin sensitivity may explain the paradoxical reduction of glucose despite a decrease in insulin secretion. Together, these findings suggest that tissue-specific methylation and possibly imprinting of GRB10 can influence glucose metabolism and contribute to T2D pathogenesis. The data also emphasize the need in genetic studies to consider whether risk alleles are inherited from the mother or the father.


Assuntos
Proteína Adaptadora GRB10/genética , Proteína Adaptadora GRB10/metabolismo , Ilhotas Pancreáticas/metabolismo , Alelos , Diabetes Mellitus Tipo 2 , Jejum/metabolismo , Estudo de Associação Genômica Ampla/métodos , Glucose/genética , Glucose/metabolismo , Humanos , Insulina/genética , Insulina/metabolismo , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Transdução de Sinais/genética
4.
Malays J Pathol ; 38(1): 65-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27126668

RESUMO

The thyroid gland is a rare site for cancer metastasis. We report a 75-year-old man who was referred with a history of hematuria and generalized bone pain for the past few months. He had a past history of partial left lobe thyroidectomy for follicular adenoma. Subsequently he was referred for a thyroid mass and a subtotal thyroidectomy showed a poorly-differentiated carcinoma. On the latest admission, the patient underwent resection of a bladder tumour with malignant histology and an immunohistochemical profile of CK7+/CK20+/34 Beta E12+/CEA-/PSA-. Re-examination of thyroid sections with immunohistochemical stains revealed the malignant cells to be CK7+/CK20+/34 Beta E12+/CEA-/TTF1-. The findings were compatible with metastasis of the bladder transitional cell carcinoma to the thyroid gland.Scans revealed multiple liver and bone metastases. The patient died 2 months after the diagnosis.


Assuntos
Carcinoma de Células de Transição/secundário , Neoplasias da Glândula Tireoide/secundário , Neoplasias da Bexiga Urinária/patologia , Idoso , Biomarcadores Tumorais/análise , Biópsia , Neoplasias Ósseas/secundário , Carcinoma de Células de Transição/química , Carcinoma de Células de Transição/cirurgia , Cistectomia , Evolução Fatal , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/secundário , Masculino , Neoplasias da Bexiga Urinária/química , Neoplasias da Bexiga Urinária/cirurgia , Imagem Corporal Total
5.
Klin Monbl Augenheilkd ; 231(6): 626-30, 2014 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-24940761

RESUMO

BACKGROUND: An estimated 10 million people suffer worldwide from vision loss caused by corneal damage. For the worst cases, the only available treatment is transplantation with human donor corneal tissue. However, in numerous countries there is a considerable shortage of corneal tissue of good quality, leading to various efforts to develop tissue substitutes. The present study aims to introduce a nanofibrous scaffold of poly(glycerol sebacate) PGS as a biodegradable implant, for the corneal tissue engineering. MATERIALS AND METHODS: Nanofibrous scaffolds were produced from PGS and poly(ε-caprolactone) (PCL) by a modified electro-spinning process. The biocompatibility of the material was tested in vitro by colorimetric MTT assay on days 3, 5, and 7 to test the cell viability of human corneal endothelium cells (HCEC). To examine a potential immunological reaction of the scaffolds, samples were exposed to mononuclear cells derived from peripheral blood (PBMCs). After an incubation period of 3 days, supernatants were assayed for apoptotic assessment and immunogenic potentials by annexin V FITC//propidium iodide and flow-cytometric analysis. RESULTS: We could successfully demonstrate that cultivation of HCECs on PGS/PCL scaffolds was possible. Compared to day 3, cell density determined by microplate absorbance was significantly higher after 7 days of cultivation (p < 0.0001). According to the MTT data, none of the samples showed toxicity. Apoptotic assessments by FACS analysis showed that no composition stimulated apoptosis or activated PBMCs occurred. All the compositions were inert for native as well as activated T/B/NK cells and monocytes. It can be concluded that leukocytes and their activity was not affected by the scaffolds. CONCLUSION: A tissue-like scaffold mimicking the human stroma could be developed. The results indicate that PGS/PCL scaffolds could be considered as ideal candidates for corneal tissue engineering as they are biocompatible in contact to corneal endothelial cells and blood cells.


Assuntos
Perda de Células Endoteliais da Córnea/terapia , Decanoatos , Endotélio Corneano/citologia , Glicerol/análogos & derivados , Nanofibras , Polímeros , Engenharia Tecidual/métodos , Alicerces Teciduais , Apoptose/fisiologia , Humanos , Ativação Linfocitária/fisiologia , Teste de Materiais , Microscopia Eletrônica de Varredura
6.
Heliyon ; 10(17): e36452, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296036

RESUMO

A novel solar-assisted multigeneration system is proposed and examined from a thermodynamic perspective, designed to simultaneously produce electricity, distilled water, and refrigeration. The system utilizes solar energy through an absorption refrigeration generator and the heat recovery mechanism of an organic Rankine cycle (ORC). The absorption refrigeration system generates both refrigeration and the necessary heat for a single-effect absorption heat transformer, which in turn produces distilled water and power via an evaporative desalination system and an ORC, respectively. Additionally, two distinct humidification-dehumidification (HDH) desalination systems are integrated to enhance freshwater production. The study evaluates the impact of various operational conditions on key performance parameters, including the coefficient of performance (COP), exergy coefficient of performance (ECOP), simple payback period (SPP), refrigeration capacity, total generated power, and distilled water production. Pareto frontiers are graphically constructed to identify optimal points and their corresponding parameter values. The results show that, with a total solar heat input of 250 kW, the system can generate 21.46 kW of electricity, 71.02 kW of refrigeration, and 100.65 g per second of distilled water. The optimal performance parameters are determined to be a COP of 2.13, an ECOP of 0.19, an SPP of 3.34 years, a power output of 16.77 kW, distilled water production of 99.84 g per second, and a refrigeration capacity of 74.44 kW.

7.
Am J Transplant ; 13(5): 1282-95, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23465054

RESUMO

In the absence of adequate compensatory regeneration, overwhelming liver damage can cause acute liver failure (ALF) and death without emergent liver transplantation (LT). Auxiliary LT produces satisfactory outcomes in this setting, with the prospect of native liver regeneration sustaining long-term survival. Since animal models only partially recapitulate human liver regeneration, we investigated the molecular mechanisms controlling it in this unique LT setting, as an exemplar of human liver regeneration. We demonstrate coordinated changes in expression of microRNA (miRNA) during regeneration that drive proliferation, innate immunity and angiogenesis. In contrast, failed regeneration in a similar cohort is associated with distinct miRNA enforcing cell cycle inhibition and DNA methylation. The miRNA expression associated with successful or failed regeneration when recapitulated in vitro, triggered expression of cardinal regeneration-linked genes promoting cell cycle entry or inhibition, respectively. Furthermore, inhibition of miRNA 150, 663 and 503, whose downregulation is associated with successful regeneration, induced cell proliferation which a key determinant of successful regeneration. Our data indicate that human liver regeneration may be orchestrated by distinct miRNA controlling key regeneration-linked processes including hepatocyte proliferation. To our knowledge this is the first characterization of molecular processes associated with human liver regeneration.


Assuntos
Regulação da Expressão Gênica , Hepatócitos/metabolismo , Falência Hepática Aguda/genética , Regeneração Hepática/fisiologia , Transplante de Fígado , MicroRNAs/biossíntese , Ciclo Celular , Proliferação de Células , Células Cultivadas , Hepatócitos/patologia , Humanos , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , MicroRNAs/genética , Análise Serial de Tecidos
8.
Ann Burns Fire Disasters ; 36(1): 29-39, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38680903

RESUMO

A platelet count of less than 150,000 per microliter of blood is called thrombocytopenia. Platelet count monitoring is essential in the care of burn patients. The aim of this study was to evaluate platelet count in groups of patients with different percentage of burns on the body surface and its relationship with the severity of burns and mortality. This retrospective descriptive cross-sectional study was performed on patients admitted to Shahid Motahari Hospital over a period of six months. The study was conducted on burn patients who were admitted to the hospital on the first day after injury. Patients were divided into two groups of with or without thrombocytopenia in the first week. Demographic information and treatment information about the patients were recorded. SPSS V.26 software was used for the statistical analysis of data. In this study, the prevalence of thrombocytopenia in the first week after burns was 36%. The variables of age, sex, duration of hospitalization, burn agent, percentage of burns and use of silver sulfadiazine ointment were significantly different in the two groups of patients. The group without thrombocytopenia had a mortality rate of 5.1%, while the group with thrombocytopenia had a rate of 32.2%. Based on the results of this study, thrombocytopenia is significantly associated with mortality in burn patients. Furthermore, the results of this study indicate that age, sex, burn agent, percentage of burns, and the use of silver sulfadiazine ointment have a clear impact on the thrombocytopenic status of patients.


La thrombopénie est définie par un compte plaquettaire <150 000/mm3, et la surveillance de la numération plaquettaire (NP) fait partie de la biologie de routine chez les brûlés. Cette étude a pour but l'évaluation de la cinétique de la NP chez des brûlés sur des surfaces variables et sa relation avec la sévérité de la brûlure et la mortalité. Il s'agit d'une étude rétrospective auprès de patients admis dans les 24h suivant leur brûlure dans le CTB de l'hôpital Shahid Motahari durant une période de 6 mois. Nous avons comparé ceux ayant subi une thrombopénie dans la première semaine aux autres (démographie, traitement), les statistiques ayant été réalisées avec SSPS version 26. La prévalence de la thrombopénie précoce est de 36%. Âge, sexe, cause, surface brûlée, recours à la sulfadiazine argentique et durée d'hospitalisation étaient différents entre les deux groupes. La mortalité des patients thrombopénique était de 32,2% VS 5,1%. Elle est significativement associée à la mortalité. L'âge, le sexe, la cause, la surface et la sulfadiazine argentique sont associées à la survenue de thrombopénie.

9.
CBE Life Sci Educ ; 20(4): ar68, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34767460

RESUMO

To enhance equity and diversity in undergraduate biology, recent research in biology education focuses on best practices that reduce learning barriers for all students and improve academic performance. However, the majority of current research into student experiences in introductory biology takes place at large, predominantly White institutions. To foster contextual knowledge in biology education research, we harnessed data from a large research coordination network to examine the extent of academic performance gaps based on demographic status across institutional contexts and how two psychological factors, test anxiety and ethnicity stigma consciousness, may mediate performance in introductory biology. We used data from seven institutions across three institution types: 2-year community colleges, 4-year inclusive institutions (based on admissions selectivity; hereafter, inclusive), and 4-year selective institutions (hereafter, selective). In our sample, we did not observe binary gender gaps across institutional contexts, but found that performance gaps based on underrepresented minority status were evident at inclusive and selective 4-year institutions, but not at community colleges. Differences in social psychological factors and their impacts on academic performance varied substantially across institutional contexts. Our findings demonstrate that institutional context can play an important role in the mechanisms underlying performance gaps.


Assuntos
Desempenho Acadêmico , Estudantes , Humanos , Aprendizagem , Grupos Minoritários , Universidades
10.
Mater Today Bio ; 5: 100042, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32159159

RESUMO

The current gold standard in peripheral nerve repair is nerve autografts for bridging gaps larger than a centimeter. However, autografts are associated with a low availability and the loss of function at the donor site. Nerve guidance conduits (NGCs) made of biocompatible and biodegradable materials reflect suitable alternatives. Clinically approved NGCs comprise either wraps that are rolled around the loose ends of the nerve or steady-state tubes; however, both lack internal guidance structures. Here, we established self-rolling NGCs to allow for gentle encapsulation of nerve cells together with supportive microenvironments, such as (1) an inner tube wall coating with a bioactive spider silk film, (2) an inner tube wall lining using an anisotropic spider silk non-woven mat, or (3) a luminal filler using an anisotropic collagen cryogel. Neuronal cells adhered and differentiated inside the modified tubes and formed neurites, which were oriented along the guidance structures provided by the spider silk non-woven mat or by the fibrillary structure of the collagen cryogel. Thus, our size-adaptable NGCs provide several features useful for peripheral nerve repair, and distinct combinations of the used elements might support and enhance the clinical outcome.

11.
Mater Today Bio ; 6: 100047, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32300754

RESUMO

Cell-laden hydrogel microcapsules enable the high-throughput production of cell aggregates, which are relevant for three-dimensional tissue engineering and drug screening applications. However, current microcapsule production strategies are limited by their throughput, multistep protocols, and limited amount of compatible biomaterials. We here present a single-step process for the controlled microfluidic production of single-core microcapsules using enzymatic outside-in cross-linking of tyramine-conjugated polymers. It was hypothesized that a physically, instead of the conventionally explored biochemically, controlled enzymatic cross-linking process would improve the reproducibility, operational window, and throughput of shell formation. Droplets were flown through a silicone delay line, which allowed for highly controlled diffusion of the enzymatic cross-linking initiator. The microcapsules' cross-linking density and shell thickness is strictly depended on the droplet's retention time in the delay line, which is predictably controlled by flow rate. The here presented hydrogel cross-linking method allows for facile and cytocompatible production of cell-laden microcapsules compatible with the formation and biorthogonal isolation of long-term viable cellular spheroids for tissue engineering and drug screening applications.

12.
Trends Endocrinol Metab ; 19(8): 277-84, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18771934

RESUMO

Glucagon, secreted by the alpha-cells of the pancreatic islets, is the most important glucose-increasing hormone of the body. The precise regulation of glucagon release remains incompletely defined but has been proposed to involve release of inhibitory factors from neighbouring beta-cells (paracrine control). However, the observation that glucose can regulate glucagon secretion under conditions when insulin secretion does not occur argues that the alpha-cell is also equipped with its own intrinsic (exerted within the alpha-cell itself) glucose sensing. Here we consider the possible mechanisms involved with a focus on ATP-regulated K(+)-channels and changes in alpha-cell membrane potential.


Assuntos
Células Secretoras de Glucagon/efeitos dos fármacos , Glucagon/metabolismo , Glucose/farmacologia , Canais KATP/fisiologia , Animais , Diabetes Mellitus/metabolismo , Diabetes Mellitus/terapia , Células Secretoras de Glucagon/metabolismo , Células Secretoras de Glucagon/fisiologia , Humanos , Hipoglicemiantes/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Modelos Biológicos , Comunicação Parácrina/fisiologia , Tolbutamida/farmacologia
13.
Gene Ther ; 15(6): 452-62, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18004400

RESUMO

Hydrodynamic gene delivery is an attractive option for non-viral liver gene therapy, but requires evaluation of efficacy, safety and clinically applicable techniques in large animal models. We have evaluated retrograde delivery of DNA to the whole liver via the isolated segment of inferior vena cava (IVC) draining the hepatic veins. Pigs (18-20 kg weight) were given the pGL3 plasmid via two programmable syringe pumps in parallel. Volumes corresponding to 2% of body weight (360-400 ml) were delivered at 100 ml s(-1) via a Y connector. The IVC segment pressure, portal venous pressure, arterial pressure, electrocardiogram (ECG) and pulse were monitored. Concurrent studies were performed in rats for interspecies comparisons. The hydrodynamic procedure generated intrahepatic vascular pressures of 101-126 mm Hg, which is approximately 4 times higher than in rodents, but levels of gene delivery were approximately 200-fold lower. Suprahepatic IVC clamping caused a fall in arterial pressure, with the development of ECG signs of myocardial ischaemia, but these abnormalities resolved rapidly. The IVC segment approach is a clinically acceptable approach to liver gene therapy. However, it is less effective in pigs than in rodents, possibly because of larger liver size or a less compliant connective tissue framework.


Assuntos
DNA/administração & dosagem , Técnicas de Transferência de Genes , Terapia Genética/métodos , Hepatopatias/terapia , Veia Cava Inferior , Animais , Linhagem Celular , Feminino , Fluoroscopia , Expressão Gênica , Fígado/metabolismo , Luciferases/genética , Modelos Animais , Ratos , Ratos Endogâmicos , Suínos , Pressão Venosa
14.
J Oral Rehabil ; 35(4): 276-82, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18321263

RESUMO

There are concerns that tooth bleaching agents may adversely affect dental materials. The aim of this study was to test the hypothesis that increasing concentrations of hydrogen peroxide (HP) are more effective than water at increasing metal ion release from two typical dental casting alloys during bleaching. Discs (n = 28 for each alloy) were prepared by casting and heat treated to simulate a typical porcelain-firing cycle. Discs (n = 7) of each alloy were immersed in either 0%, 3%, 10% or 30% (w/v) HP solutions for 24 h at 37 degrees C. Samples were taken for metal ion release determination using inductively coupled plasma-mass spectrometry and the data analysed using a two-way anova followed by a one-way anova. The surface roughness of each disc was measured using a Talysurf contact profilometer before and after bleaching and the data analysed using a paired t-test. With the exception of gold, the differences in metal ion concentration after treatment with 0% (control) and each of 3%, 10% and 30% HP (w/v) were statistically significant (P < 0.05). Metal ion release from the two alloys increased with increasing HP concentrations (over 3000% increase in Ni and 1400% increase in Pd ions were recorded when HP concentration increased from 0% to 30%). Surface roughness values of the samples before and after bleaching were not significantly different (P > 0.05) Exposure of the two dental casting alloys to HP solutions increased metal ion release of all the elements except gold.


Assuntos
Ligas Dentárias/química , Peróxido de Hidrogênio/efeitos adversos , Metais , Oxidantes/efeitos adversos , Clareamento Dental/efeitos adversos , Corrosão , Humanos , Íons , Teste de Materiais/métodos , Propriedades de Superfície
15.
Sci Rep ; 8(1): 6925, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720689

RESUMO

Animal models of allergic airways inflammation are useful tools in studying the pathogenesis of asthma and potential therapeutic interventions. The different allergic airways inflammation models available to date employ varying doses, frequency, duration and types of allergen, which lead to the development of different features of asthma; showing varying degrees of airways inflammation and hyper-responsiveness (AHR) and airways remodeling. Models that also exhibit airway remodeling, a key feature of asthma, in addition to AHR and airway inflammation typically require 5-12 weeks to develop. In this report, we describe a 4-week mouse model of house dust mite (HDM)-induced allergic airways inflammation, and compare the phenotypic features of two different doses of HDM exposures (10 µg and 25 µg) for 5 days/week with a well-characterized 8-week chronic HDM model. We found that 4 weeks of intranasal HDM (25 µg in 35 µl saline; 5 days/week) resulted in AHR, airway inflammation and airway remodeling that were comparable to the 8-week model. We conclude that this new 4-week HDM model is another useful tool in studies of human asthma that offers advantages of shorter duration for development and decreased costs when compared to other models that require longer durations of exposure (5-12 weeks) to develop.


Assuntos
Remodelação das Vias Aéreas , Alérgenos/imunologia , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/patologia , Pyroglyphidae/imunologia , Animais , Biomarcadores , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Imunização , Imunoglobulina E/imunologia , Mediadores da Inflamação/metabolismo , Contagem de Leucócitos , Camundongos , Fatores de Tempo
16.
J Dent ; 35(11): 845-50, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17869403

RESUMO

OBJECTIVES: Tooth bleaching agents may adversely affect tooth structure. The aim of this study was to investigate the effect of hydrogen peroxide concentration on mineral loss and microhardness of bovine teeth. METHODS: Twenty-six freshly extracted intact bovine incisor teeth were stored in distilled water. Five teeth were sectioned and four samples (2 mm x 2 mm x 1.5 mm) each of enamel and dentine were obtained from each tooth. The samples of enamel and dentine were divided into four groups and immersed in either 0%, 3%, 10% or 30% (w/v) hydrogen peroxide solutions for 24h at 37 degrees C. Samples from the solutions were taken for ion release analysis using inductively coupled plasma mass spectrometry. The remaining 21 teeth were mounted in epoxy resin and the upper surface of the specimens were ground and polished to expose the enamel and dentine for microhardness measurements. These specimens were randomly divided into three equal groups and Vickers microhardness values were recorded on the enamel and dentine surfaces of each group before and after bleaching. RESULTS: The differences in ion release concentration after treatment with 0% (control) and each of 3%, 10% and 30% hydrogen peroxide (w/v) were statistically significant (p<0.025). The release of calcium and phosphorous ions increased with increasing hydrogen peroxide concentrations. A significant reduction (p<0.05) in Vickers microhardness values for enamel was recorded after bleaching. CONCLUSIONS: Ion release from both enamel and dentine increased with increasing hydrogen peroxide concentration. Microhardness of enamel decreased significantly with bleaching.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Peróxido de Hidrogênio/administração & dosagem , Oxidantes/administração & dosagem , Clareamento Dental/métodos , Animais , Cálcio/análise , Bovinos , Dureza , Espectrometria de Massas , Minerais/análise , Fósforo/análise , Distribuição Aleatória , Temperatura , Fatores de Tempo
17.
J Dent ; 35(2): 172-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16949717

RESUMO

OBJECTIVES: The aim of this study was to investigate the effect of hydrogen peroxide (HP) concentration on metal ion release from dental amalgam. METHODS: Dental amalgam discs (n=25) were prepared by packing amalgam into cylindrical plastic moulds (10 mm diameter and 2 mm height). The discs were divided into five equal groups and each group was immersed in 20 ml of either 0%, 1%, 3%, 10% or 30% HP solution for 24 h at 37 degrees C. Samples were taken for metal ion release determination (Hg, Ag, Sn and Cu) using inductively coupled plasma mass spectrometry (ICP-MS). The surface roughness of each disc was measured before and after bleaching. RESULTS: The differences in concentration of metal ions released after treatment with 0% (control) and each of 1%, 3%, 10% and 30% HP were statistically significant (p<0.05). Metal ion release for the elements (Hg, Ag, Sn and Cu) increased with exposure to increasing concentrations of HP. Surface roughness measurements of the samples before and after treatments with HP solutions were not significantly different (p>0.05). CONCLUSIONS: Exposure to HP bleaching agent was associated with increased metal ion released from dental amalgams compared to treatment with a control solution. Ion release was in proportion to the peroxide concentration tested, with the highest concentration associated with the greatest metal ion release for all elements investigated.


Assuntos
Amálgama Dentário/química , Peróxido de Hidrogênio/química , Metais/química , Oxidantes/química , Cobre/química , Ligas Dentárias/química , Humanos , Peróxido de Hidrogênio/administração & dosagem , Íons , Espectrometria de Massas , Teste de Materiais , Mercúrio/química , Oxidantes/administração & dosagem , Prata/química , Propriedades de Superfície , Temperatura , Fatores de Tempo , Estanho/química
18.
Middle East J Anaesthesiol ; 19(2): 415-22, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17684881

RESUMO

BACKGROUND: Headache after spinal anesthesia is a common complication is patients undergoing this procedure. In this study we evaluated the efficacy of intravenous hydrocortisone in the treatment of headache after spinal anesthesia in women who have undergone cesarean section. METHODS: Sixty patients with headache after spinal anesthesia were included. Patients randomly allocated into two groups, 30 patients received only conventional therapy (complete bed rest, hydration, acetaminophen and pethidine). Other 30 patients received conventional therapy plus intravenous hydrocortisone (200 mg first, then 100 mg TID for 48 hours). Mean (+/- SD) of headache intensity at 0, 6, 24, and 48 hours after beginning of treatment was measured using visual analog scale. RESULTS: There was no significant difference in headache intensity between two groups before beginning of treatment. After 6 hours, the mean of headache intensity in 30 patients treated conventionally was 6.63 (+/- 1.35) while it was 2.77 (+/- 1.07) in other patients received intravenous hydrocortisone too (p <0.001). After 24 hours, mean headache intensity was 3.87 (+/- 1.63) in conventionally treated group versus 0.73 (+/- 0.74) in hydrocortisone group (p <0.001). After 48 hours, mean headache intensity was 1.87 (+/- 0.93) in conventionally treated group versus 0.63 (+/- 0.61) in hydrocortisone group (p = 0.001). CONCLUSIONS: This study showed the therapeutic effects of intravenous hydrocortisone in reducing headache after spinal anesthesia in women who underwent cesarean section. Its mechanism of action is yet to be determined.


Assuntos
Anti-Inflamatórios/uso terapêutico , Hidrocortisona/uso terapêutico , Cefaleia Pós-Punção Dural/tratamento farmacológico , Acetaminofen/administração & dosagem , Adolescente , Adulto , Analgésicos não Narcóticos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Raquianestesia/efeitos adversos , Anti-Inflamatórios/administração & dosagem , Cesárea , Feminino , Hidratação , Humanos , Hidrocortisona/administração & dosagem , Injeções Intravenosas , Meperidina/administração & dosagem , Medição da Dor/métodos , Cefaleia Pós-Punção Dural/etiologia , Gravidez , Descanso , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
19.
Ann Burns Fire Disasters ; 30(1): 13-17, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28592928

RESUMO

There are two types of prognostic model - burn-specific and general - to predict mortality risk in burn patients. Most prediction models were devised in developed countries. The aim of this study was to compare the performance of six outcome models in a developing country. In a retrospective cohort study, data of all thermal burned adult patients (age ≥ 18 years) admitted to the Burn Intensive Care Unit (BICU) were collected and then the following six prediction models were used to assess each patient: Acute Physiology and Chronic Health Evaluation (APACHE II), Abbreviated Burn Severity Index (ABSI), Belgian Outcome in Burn Injury (BOBI), the Ryan model, revised Baux and FLAMES model. Discriminative ability and goodness-of-fit of the prediction models were determined by receiver operating characteristic curve analysis and Hosmer-Lemeshow tests. We included 238 patients (mean age: 38.3 ± 18.39 years, average TBSA: 58.27% ± 24.55) in our study; 172 (72.3%) of them were diagnosed with inhalation injury and 178 (72.4%) were intubated. Mortality rate was 69.7%. Deceased patients had significantly higher mean age, %TBSA and number of inhalation injury. The area under the curve of the models was between 64.5 (APACHE II) and 85.9 (ABSI). The best estimation of predicted mortality was obtained with the ABSI model (67.2%).


Des scores de gravité spécifiques ou généraux peuvent être utilisés pour évaluer le pronostic d'un brûlé, la plupart d'entre eux ayant été construits dans des pays développés. Le but de cette étude était de comparer 6 d'entre eux dans un pays en développement. Les données de tous les patients admis en réanimation spécialisée ont été collectées pour calculer 6 scores de gravité qui étaient : APACHE II, ABSI, BOBI, Ryan, Baux révisé et FLAMES. La sensibilité et la spécificité de ces modèles ont été analysées par courbe ROC et test de Hosmer-Lemeshow. Deux cent trente huit patients de 38,3 +/- 18,39 ans, brûlés sur 58,27 +/- 24,55% de SCT ont été inclus. Cent soixante douze (72,3%) avaient inhalé des fumées et 178 (72,4%) avaient été intubés. La mortalité était de 69,7%. Les patients décédés étaient plus âgés, brûlés sur une plus grande surface et avaient plus fréquemment inhalé des fumées. Les aires sous la courbe ROC allaient de 64,5 (APACHE II) à 85,9 (ABSI). Cette étude confirme que l'ABSI reste le meilleur score de gravité pour les patients brûlés.

20.
Dent Mater ; 22(10): 948-53, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16375959

RESUMO

OBJECTIVES: There is concern that hydrogen peroxide generated by tooth bleaching agents may cause enhanced metal ion release (including mercury) from dental amalgam following contact. The aim of this in vitro study was therefore to investigate the effect of a carbamide peroxide (CP) based tooth bleaching gel on metal ion release from dental amalgam. METHODS: Dental amalgam discs were prepared according to the manufacturers' instructions. These were treated with either a 10% carbamide peroxide (CP) gel or a 0% CP gel for 24h. Discs were carefully wiped with cotton wool before immersion in distilled water (20 ml) for 24h at 37 degrees C. Following immersion, water samples were taken for metal ion release determination (Ag, Cu, Hg and Sn) using inductively coupled plasma mass spectrometry methods. The specimens were further evaluated for surface changes using scanning electron microscopy (SEM) and Talysurf surface roughness measurements. RESULTS: The differences in concentration of metal ions released after treatment with the 10% CP gel and a placebo gel treatment were not statistically significant (p>0.05). For example, mercury release following treatment with the 10% CP gel and the 0% CP gel was found to be 1.17(0.5) and 0.57(0.1)microgcm(-2), respectively. Roughness measurements for samples treated with the 10% CP gel and 0% CP gel were 2.23(0.47) and 1.74(0.16)microm, respectively, again showing no significant difference between groups (p>0.05). SEM images of the amalgam surfaces showed no apparent differences between treatments. SIGNIFICANCE: Treatment with a 10% CP gel did not significantly enhance subsequent metal ion release from dental amalgams compared to a control gel, contradicting previously published studies.


Assuntos
Amálgama Dentário/química , Oxidantes/química , Peróxidos/química , Clareamento Dental , Ureia/análogos & derivados , Peróxido de Carbamida , Ligas Dentárias/química , Combinação de Medicamentos , Íons/análise , Metais/análise , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Ureia/química
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