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1.
Discov Med ; 36(185): 1162-1168, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38926102

RESUMO

BACKGROUND: Atypical acinar cell foci (AACF) seen in pancreatic cancer are fatal and have been studied with some causative agents. However, for the first time, the effect of acetylsalicylic acid with nitric oxide (NO-ASA) on AACF was examined in this study. Although NO-ASA has very successful inhibitory effects against some types of cancer, it has not been investigated whether they can exert their inhibition effects on AACFs. METHODS: For experimental purposes, 21 14-day-old male Wistar albino rats were used. Azaserine (30 mg/kg) was dissolved in 0.9% NaCl solution and injected intraperitoneally (i.p.) into 14 rats, except for the Control group (Cont) rats, for three weeks. Rats that were injected with azaserine once a week for three weeks and those that did not receive treatment were divided into experimental groups. 15 days after the end of the azaserine injection protocol, NO-ASA was applied to azaserine with NO-ASA (Az+NO-ASA) group rats three consecutive times with an interval of 15 days by gavage. At the end of the 5-month period, pancreatic tissue was dissected and weighed. Pancreas preparations prepared from histological sections were examined for AACF burden and analyzed via a video image analyzer. One-way analysis of variance (ANOVA) non-parametric statistical analyses were performed to test whether there was a difference between the averages of the experimental and Control groups. RESULTS: AACF burden in both groups injected with azaserine was found to be statistically significant in all categories compared to that of the Control group (p < 0.05). The average Calculated Estimated average AACF volume (mm3) values, the Calculated estimated average AACF diameter (µm), the Estimated average number of AACF per unit volume, AACF rate as a % of Calculated Organ Volume were higher in the AzCont group rats than in the Az+NO-ASA group, when compared, and there was an important level statistical difference between the groups (p < 0.05). It was determined that for all parameters AACFs load in Az+NO-ASA group rats were significantly reduced compared to that of AzCont group rats (p < 0.05). CONCLUSIONS: We observed that, as a result of the NO-ASA application, the experimental AACF focus ratio created by azaserine injection was significantly inhibited. The inhibitory effect of AACFs in Az+NO-ASA group rats may have resulted from the significant and independent chemopreventive and/or chemotherapeutic activity of NO-ASA against exocrine pancreatic AACF foci.


Assuntos
Células Acinares , Aspirina , Óxido Nítrico , Pâncreas Exócrino , Neoplasias Pancreáticas , Ratos Wistar , Animais , Masculino , Aspirina/farmacologia , Aspirina/uso terapêutico , Aspirina/administração & dosagem , Óxido Nítrico/metabolismo , Ratos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Células Acinares/metabolismo , Pâncreas Exócrino/efeitos dos fármacos , Pâncreas Exócrino/patologia
2.
Int J Dent Hyg ; 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37357382

RESUMO

OBJECTIVES: The purpose of this study was to compare the effectiveness of three different instruments on cement loss, porosity and micro-crack formation, which was not evaluated before, following scaling and root planning (SRP) using micro-computed tomography (micro-CT). METHODS: In this experimental study, 30 single-rooted extracted human teeth were used and divided into three groups. All the teeth were scanned with micro-CT before and after SRP. Group 1: SRP was performed with Gracey curettes, Group 2: SRP was performed by using an ultrasonic device, and Group 3: SRP was performed by using diamond burs. Cement loss from the root surface, porosity, and micro-crack formation in the root dentine were analysed. Micro-CT is used for qualitative and quantitative analysis of samples. The obtained data were analysed statistically (p < 0.05). RESULTS: Minimum cement loss following SRP was detected with ultrasonic scaler (26.98 mm3 ), whereas the highest was created by diamond burs (96.20 mm3 ) (p < 0.05). The total porosity values after SRP were 0.278%, 0.334% and 0.252% for Groups 1, 2 and 3, respectively. Although Group 3 had the least porosity values, there was no statistically significant difference between the groups. The highest micro-crack formation was seen in Group 2 and the lowest was in Group 1 with a significant difference (p < 0.05). CONCLUSIONS: More cement loss was observed with diamond burs. Ultrasonic devices appear to be a viable alternative to instrumentation with curettes. However, ultrasonic devices should be used carefully because of micro-crack formation since the micro-crack resulting from instrumentation with hand instruments is the least of all.

3.
Proc Inst Mech Eng H ; 236(5): 665-675, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35303774

RESUMO

Violence related injuries and deaths mostly caused by firearms are a major problem throughout the world. Understanding the factors that control the extent of hard-soft tissue wound patterns using computer imaging techniques, numerical methods, and machine learning algorithms may help physicians to diagnose and treat those injuries more properly. Here, we investigate the use of computational results coupled with the pattern recognition algorithms to develop an approach for forensic applications. Initially, computer tomography (CT) images of the patient whose leg was shot by a 9 × 19 parabellum bullet are used to construct the FE models of that patient's femoral bone and the surrounding soft tissues. Then, Hounsfield units-based material properties are assigned to elements of the bone. To simulate the full range of loading conditions encountered in ballistic events, a constitutive model that captures the strain-rate dependent response is implemented. The entrance pathway vector of the bullet is directed in accordance with the patient's wound and the simulations are deployed for the cases having various inlet velocities such as 150, 200, 250, 300, and 350 m/s. Once the FE results for each case are obtained, they are processed with supervised machine learning algorithms to classify the wound and inlet velocity correspondence. The results demonstrate that they can be diagnosed with a percent accuracy of 97.3, 97.5, and 98.3 for the decision tree (DT), k-nearest neighbors (kNN) and support vector machine (SVM) classifier, respectively. This approach may provide a useful framework in classifying the wound type, predicting the bullet impact velocity and its firing distance.


Assuntos
Armas de Fogo , Ferimentos por Arma de Fogo , Análise de Elementos Finitos , Balística Forense/métodos , Humanos , Tomografia Computadorizada por Raios X , Ferimentos por Arma de Fogo/diagnóstico por imagem
4.
Ann Biomed Eng ; 49(12): 3388-3400, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34472001

RESUMO

This study aimed to investigate the relationship between the micro structural properties of the subchondral trabecular bone (STB) and the macro mechanical properties of the articular cartilage (AC) in patients with osteoporotic (OP) and osteopenic (OPE) fractures. Sixteen femoral head samples (OP;OPE, n = 8 each) were obtained from female patients who underwent hip hemiarthroplasty. STB and AC specimens were harvested from those heads. Bone specimens were scanned using µ-CT to determine the micro structural properties. In-situ nondestructive compressive tests were performed for the cartilages to obtain elastic properties. The finite element technique was implemented on STB models created from µ-CT data to compute apparent elastic modulus. In addition, dynamic cyclic destructive tests were performed on STB and AC specimens to assess failure cycles. The results demonstrated that STB specimens in OPE group have more interconnected structure and higher cyclic dynamic strength than those in OP group. Furthermore, bone mineral density, failure cycle, and trabecular number of STB were positively correlated with the cartilage failure cycle, which indicates that STB alteration may affect the macroscopic mechanical properties of AC. The findings suggest that STB loss correlates with a decrease in cartilage strength and that improving of bone quality may prevent cartilage weakness.


Assuntos
Doenças Ósseas Metabólicas/fisiopatologia , Cartilagem Articular/fisiopatologia , Fraturas do Fêmur/fisiopatologia , Cabeça do Fêmur/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Densidade Óssea , Doenças Ósseas Metabólicas/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Módulo de Elasticidade , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/diagnóstico por imagem , Humanos , Fraturas por Osteoporose/diagnóstico por imagem , Microtomografia por Raio-X
6.
Surg Radiol Anat ; 43(12): 1933-1943, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33954823

RESUMO

PURPOSE: Although the fresh frozen (FF) cadaver is preferred for surgical applications, it is limited due to short usage time, unsuitable for reuse and the risk of infection. Due to its limited use, FF cadavers, which are covered by import in countries with insufficient body donation cause low-cost effectiveness. With the increase of real human tissue specimen necessities for surgical training, long-term preservation of the cadavers is crucial due to changes in mechanical properties. Therefore, studies on embalming solutions have increased in recent years. METHODS: We quantify the biomechanical properties of human parietal bones preserved via modified larssen solution (MLS) and compare the results with the specimens preserved as FF and fixed with 10% formalin-based solution (F10). The rectangular samples of 24 parietal bones of male individuals were resected from MLS-embalmed, F10-embalmed and FF cadavers to form three groups each containing eight samples. These specimens were tested longitudinally to identify mechanical properties. RESULTS: The tensile test results showed that there is not a significant difference between the groups in terms of stiffness, elastic modulus, strain at ultimate stress, failure strain and effective plastic strain. However, the yield stress, ultimate stress, yield strain, failure stress and total energy and post-yield properties are significantly lower in F10 than MLS and FF groups. CONCLUSION: It is observed that the mechanical properties of MLS preserved and FF parietal bones have almost similar properties. Thus, it can be concluded that MLS is a suitable fixative solution for bone studies and bone-related surgical anatomy training applications.


Assuntos
Formaldeído , Osso Parietal , Cadáver , Embalsamamento , Fixadores , Humanos , Masculino
7.
J Cancer Res Ther ; 15(1): 231-236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880783

RESUMO

AIM: The effect of acetylsalicylic acid (ASA) on thiol levels was studied in a rat model of azaserine carcinogenesis. MATERIALS AND METHODS: ASA and azaserine were applied to the animals to research changes in cellular sulfhydryl (-SH) content and variations in free and protein-bound molecules containing the -SH group. Such effects in rats injected with azaserine were investigated at low (200 ppm) and high (400 ppm) concentrations of ASA over a relatively short (6 months) and a relatively long (12 months) period. RESULTS: Changes in the hepatic, pancreatic, and renal -SH contents were also determined. CONCLUSION: Compared to the other tissues studied, the liver contained the highest levels of both free and protein-bound -SH.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Azasserina/toxicidade , Carcinógenos/toxicidade , Neoplasias/prevenção & controle , Animais , Relação Dose-Resposta a Droga , Humanos , Rim/química , Rim/efeitos dos fármacos , Rim/patologia , Fígado/química , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Neoplasias/induzido quimicamente , Neoplasias/patologia , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/patologia , Neoplasias Experimentais/prevenção & controle , Pâncreas/química , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Ratos , Ratos Wistar , Compostos de Sulfidrila/análise , Resultado do Tratamento
8.
J Sci Food Agric ; 99(5): 2589-2595, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30411365

RESUMO

BACKGROUND: Vacuum evaporation (VE) process is widely utilized in fruit juice evaporation to preserve quality attributes of final product. However, it has some disadvantages such as possible degradation of aroma components or volatile fatty acids due to long process time, and low energy efficiency of process. Pomegranate juice having 17.5% total soluble solid (TSS) content was evaporated to 40% TSS by ohmic heating assisted vacuum evaporation (OVE; 7.5, 10 and 12.5 V cm-1 ) and VE in the present study. The effects of the evaporation methods on pH, titratable acidity and colour values, antioxidant activity (AA), total monomeric anthocyanin (TMA), total phenolic content (TPC), hydroxymethylfurfural (HMF) and invert sugar content of pomegranate juice concentrates were compared. RESULTS: The colour properties, TMA, TPC and AA values of pomegranate juice concentrates evaporated by OVE were more influenced than those evaporated by VE. The degradation of sugars was minimized for OVE processes at high voltage gradients (10 and 12.5 V cm-1 ), and HMF content of pomegranate juice concentrated by OVE was lower than VE. CONCLUSION: It is thought that electrochemical reactions occurred because of the use of titanium electrodes during the OVE process caused these quality changes in pomegranate juice concentrates having high acidity. Hence, it was concluded that the utilization of relatively more electrochemically inert electrodes should be investigated in further studies to better evaluate the of influence of OVE method on quality attributes of different fruit juices. © 2018 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Lythraceae/química , Antocianinas/química , Antioxidantes/química , Cor , Manipulação de Alimentos/instrumentação , Fenóis/química , Vácuo
9.
PLoS One ; 13(12): e0209151, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30576356

RESUMO

Mucus constitutes a protective layer which coats the gastrointestinal tract, controlling interactions of both commensal and pathogenic microbes with underlying tissues. Changes to the mucus barrier, for example due to altered mucin expression or external stimuli, may impact interactions with microbes and thus potentially contribute to altered gut homeostasis, onset of inflammation, or pathogen invasion. Food-associated stimuli, including lipids, have been shown to change mucus barrier properties and reduce transport of model drug carriers through mucus. Here, we explore the impact of lipids, specifically triglycerides in a model intestinal medium mimicking a fed state, on Escherichia coli (E. coli) transport through mucus by directly imaging swimming patterns and analyzing associated changes in mucus structure. Lipids in model fed state intestinal contents reduced E. coli speed and track linearity within mucus. These changes may be due in part to changes in molecular interactions within the mucus network as well as crowding of the mucus network by lipid emulsion droplets, which visibly stay intact in the mucus gel. In addition, observed physical interactions between bacteria and lipid structures may impact microbial speed and trajectories. As lipids are normal food components and thus represent safe, mild stimuli, these results support exploration of lipid-based strategies to alter the mucus barrier to control interactions with microbes and potentially prevent microbial invasion of underlying epithelium.


Assuntos
Escherichia coli/fisiologia , Lipídeos/farmacologia , Locomoção/efeitos dos fármacos , Animais , Escherichia coli/efeitos dos fármacos , Gotículas Lipídicas/química , Lipídeos/química , Microscopia de Vídeo , Muco/química , Muco/metabolismo , Suínos
10.
Bioprocess Biosyst Eng ; 40(8): 1189-1196, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28488138

RESUMO

This work presents the synthesis of new mercapto calix[4]arenes derivatives (4 and 5). These derivatives were capped on Fe3O4 magnetic nanoparticles and subsequently encapsulated with Candida rugosa through sol-gel method to furnish enc-4 and enc-5, respectively, to enhance catalytic activity and enantioselectivity of lipase for hydrolysis reaction of racemic flurbiprofen methyl ester. Catalytic activity and enantioselectivity of enc-4 and enc-5 were assayed at different pH and temperature conditions and it was found that the resultant encapsulated enzyme exhibited higher thermal and operational stabilities compared to the free lipase in which enc-5 showed the excellent rate of enantioselectivity (E = 176) for S-flurbiprofen better than free lipase (E = 137) at pH 7 and 35 °C for 48 h. The time study shows that enantioselectivity reached the maximum value of E = 244 after 72 h. Catalytic activity  of these materials was hardly affected by 20 and 23% after five usages of enc-4 and enc-5, respectively.


Assuntos
Nanopartículas Metálicas , Calixarenos , Candida , Flurbiprofeno , Lipase , Estereoisomerismo , Temperatura
11.
J Orthop Surg (Hong Kong) ; 25(1): 2309499017692718, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28215116

RESUMO

PURPOSE: Osteopenia and osteoporosis are the two most common musculoskeletal disorders in the elderly population. We determined whether osteopenic and osteoporotic patients with fractures exhibit differences in trabecular morphology and biomechanical properties of bone. METHODS: Fourteen osteopenic patients and 28 osteoporotic patients with hip fractures who underwent hemiarthroplasty for proximal femoral fractures caused by low-energy injury were included. Bone mineral density (BMD) measurements were performed. Compression tests and high-resolution micro-computed tomography were used to assess cancellous bone samples obtained from the principal compressive region of the femoral head. RESULTS: The BMD values were lower in the osteoporotic patients than in the osteopenic patients ( p < 0.05). There was a significant difference in the yield stress values between the groups ( p < 0.05). However, no significant differences in the strain energy density, stiffness and Young's modulus were observed between the groups ( p > 0.05). The mean maximum stress was significantly higher in the osteoporotic patients than in the osteopenic patients ( p < 0.05). Although structural parameters, including bone volume (BV), BV fraction, trabecular thickness, trabecular connectivity density and trabecular number, were higher in the osteopenic patients, the differences were not significant ( p > 0.05). Trabecular separation values were significantly higher in the osteoporotic patients ( p < 0.05). CONCLUSION: Our results showed that the trabecular morphology and biomechanical properties of bone were not significantly different between osteopenic and osteoporotic patients in terms of some parameters.


Assuntos
Densidade Óssea , Doenças Ósseas Metabólicas/complicações , Cabeça do Fêmur/diagnóstico por imagem , Fraturas do Quadril/diagnóstico , Fraturas por Osteoporose/diagnóstico , Microtomografia por Raio-X/métodos , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/diagnóstico , Feminino , Fraturas do Quadril/etiologia , Humanos , Masculino
12.
J Drug Target ; 23(7-8): 768-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26453172

RESUMO

Intestinal mucus provides a significant barrier to transport of orally delivered drug carriers, as well as other particulates (e.g. food, microbes). The relative significance of particle size, surface chemistry, and dosing medium to mucus barrier properties is not well characterized, but important in designing delivery systems targeted to the intestinal mucosa. In this study, multiple particle tracking (MPT) was used to study diffusion of 20-500 nm diameter carboxylate- and polyethylene glycol-(PEG-)functionalized polystyrene model carriers through intestinal mucus. The impact of exposure to mucus in buffer versus a partially digested triglyceride mixture was explored. Effective diffusivity of particles in intestinal mucus decreased with an increasing particle size less than and more than theoretically (Stokes-Einstein) expected in a homogenous medium when dosed in buffer and model-fed state intestinal contents, respectively. For example, effective diffusivity decreased 2.9- versus 20-fold with increase in the particle size from 100 to 500 nm when dosed to mucus in buffer versus lipid-containing medium. Functionalization with PEG dramatically decreased sensitivity to lipids in a dosing medium. The results indicate that reduction of particle size may increase particle transport through intestinal mucus barriers, but these effects are strongly dependent on intestinal contents and particle surface chemistry.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Mucosa Intestinal/metabolismo , Lipídeos/química , Administração Oral , Animais , Transporte Biológico , Difusão , Tamanho da Partícula , Polietilenoglicóis/química , Poliestirenos/química , Suínos , Triglicerídeos/metabolismo
13.
Biomaterials ; 54: 1-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25907034

RESUMO

Orally delivered drugs and nutrients must diffuse through mucus to enter the circulatory system, but the barrier properties of mucus and their modulation by physiological factors are generally poorly characterized. The main objective of this study was to examine the impact of physicochemical changes occurring upon food ingestion on gastrointestinal (GI) mucus barrier properties. Lipids representative of postprandial intestinal contents enhanced mucus barriers, as indicated by a 10-142-fold reduction in the transport rate of 200 nm microspheres through mucus, depending on surface chemistry. Physiologically relevant increases in [Ca(2+)] resulted in a 2-4-fold reduction of transport rates, likely due to enhanced cross-linking of the mucus gel network. Reduction of pH from 6.5 to 3.5 also affected mucus viscoelasticity, reducing particle transport rates approximately 5-10-fold. Macroscopic visual observation and micro-scale lectin staining revealed mucus gel structural changes, including clumping into regions into which particles did not penetrate. Histological examination indicated food ingestion can prevent microsphere contact with and endocytosis by intestinal epithelium. Taken together, these results demonstrate that GI mucus barriers are significantly altered by stimuli associated with eating and potentially dosing of lipid-based delivery systems; these stimuli represent broadly relevant variables to consider upon designing oral therapies.


Assuntos
Cálcio/metabolismo , Conteúdo Gastrointestinal/química , Mucosa Intestinal/metabolismo , Metabolismo dos Lipídeos/fisiologia , Muco/química , Muco/metabolismo , Animais , Digestão/fisiologia , Módulo de Elasticidade/fisiologia , Alimentos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/química , Masculino , Ratos , Ratos Sprague-Dawley , Suínos , Viscosidade
14.
Macromol Biosci ; 15(5): 712-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25644515

RESUMO

Mucus forms a protective hydrogel layer over the intestinal epithelium, presenting a selective and robust barrier to the uptake of particulates and microbe invasion. Disease can alter mucus production and composition, thus potentially modifying mucosal barrier properties. Hirschsprung's disease (HD) is a developmental abnormality of the nervous system often complicated by intestinal infection. An investigation of colonic mucus barrier properties in an HD animal model, endothelin receptor B mutant mice, revealed significantly reduced microsphere (passive) and microbe (active) transport rates (7-fold and 3.6-fold, respectively, in proximal colonic mucus) relative to wild-type. Transport differences were evident in both the ganglionic and aganglionic colon segments, in agreement with the risk of HD-associated enterocolitis after surgery to remove aganglionic colon segments. The development of therapies aimed at altering colonic mucus barrier properties could be explored towards preventing the onset of enterocolitis in HD.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Escherichia coli/fisiologia , Doença de Hirschsprung/microbiologia , Doença de Hirschsprung/patologia , Muco/microbiologia , Animais , Transporte Biológico Ativo , Colo/microbiologia , Colo/patologia , Camundongos , Receptor de Endotelina B/deficiência , Receptor de Endotelina B/metabolismo
15.
Biomed Res Int ; 2014: 931537, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25177703

RESUMO

The aim of the study was to investigate the efficacy of greater trochanteric fixation using a multifilament cable to ensure abductor lever arm continuity in patients with a proximal femoral fracture undergoing partial hip arthroplasty. Mean age of the patients (12 men, 20 women) was 84.12 years. Mean follow-up was 13.06 months. Fixation of the dislocated greater trochanter with or without a cable following load application was assessed by finite element analysis (FEA). Radiological evaluation was based on the distance between the fracture and the union site. Harris hip score was used to evaluate final results: outcomes were excellent in 7 patients (21.8%), good in 17 patients (53.1%), average in 5 patients (15.6%), and poor in 1 patient (9.3%). Mean abduction angle was 20.21°. Union was achieved in 14 patients (43.7%), fibrous union in 12 (37.5%), and no union in 6 (18.7%). FEA showed that the maximum total displacement of the greater trochanter decreased when the fractured bone was fixed with a cable. As the force applied to the cable increased, the displacement of the fractured trochanter decreased. This technique ensures continuity of the abductor lever arm in patients with a proximal femoral fracture who are undergoing partial hip arthroplasty surgery.


Assuntos
Artroplastia de Quadril/instrumentação , Fraturas do Fêmur/fisiopatologia , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/instrumentação , Articulação do Quadril/fisiopatologia , Articulação do Quadril/cirurgia , Idoso de 80 Anos ou mais , Artroplastia de Quadril/métodos , Simulação por Computador , Feminino , Análise de Elementos Finitos , Fixação Interna de Fraturas/métodos , Prótese de Quadril , Humanos , Masculino , Modelos Biológicos , Ajuste de Prótese/instrumentação , Ajuste de Prótese/métodos , Estresse Mecânico , Resistência à Tração , Resultado do Tratamento , Suporte de Carga
16.
PLoS One ; 9(6): e99944, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24945437

RESUMO

Hirschsprung disease-associated enterocolitis (HAEC) leads to significant mortality and morbidity, but its pathogenesis remains unknown. Changes in the colonic epithelium related to goblet cells and the luminal mucus layer have been postulated to play a key role. Here we show that the colonic epithelium of both aganglionic and ganglionic segments are altered in patients and in mice with Hirschsprung disease (HSCR). Structurally, goblet cells were altered with increased goblet cell number and reduced intracellular mucins in the distal colon of biopsies from patients with HSCR. Endothelin receptor B (Ednrb) mutant mice showed increased goblet cell number and size and increased cell proliferation compared to wild-type mice in aganglionic segments, and reduced goblet cell size and number in ganglionic segments. Functionally, compared to littermates, Ednrb-/- mice showed increased transepithelial resistance, reduced stool water content and similar chloride secretion in the distal colon. Transcript levels of goblet cell differentiation factors SPDEF and Math1 were increased in the distal colon of Ednrb-/- mice. Both distal colon from Ednrb mice and biopsies from HSCR patients showed reduced Muc4 expression as compared to controls, but similar expression of Muc2. Particle tracking studies showed that mucus from Ednrb-/- mice provided a more significant barrier to diffusion of 200 nm nanoparticles as compared to wild-type mice. These results suggest that aganglionosis is associated with increased goblet cell proliferation and differentiation and subsequent altered surface mucus properties, prior to the development of inflammation in the distal colon epithelium. Restoration of normal goblet cell function and mucus layer properties in the colonic epithelium may represent a therapeutic strategy for prevention of HAEC.


Assuntos
Colo/patologia , Gânglios Parassimpáticos/patologia , Células Caliciformes/patologia , Doença de Hirschsprung/patologia , Muco/metabolismo , Receptor de Endotelina B/genética , Receptores de Endotelina/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Transporte Biológico , Contagem de Células , Diferenciação Celular , Tamanho Celular , Colo/metabolismo , Fezes/química , Deleção de Genes , Regulação da Expressão Gênica , Células Caliciformes/metabolismo , Doença de Hirschsprung/genética , Doença de Hirschsprung/metabolismo , Humanos , Camundongos , Camundongos Knockout , Mucina-2/genética , Mucina-2/metabolismo , Mucina-4/genética , Mucina-4/metabolismo , Nanopartículas/metabolismo , Técnicas de Patch-Clamp , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Receptor de Endotelina B/deficiência , Receptores de Endotelina/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-24779977

RESUMO

In this study, ochratoxin A (OTA) in 55 home-made, 20 commercial and 7 organic grape pekmez (grape molasses) produced in Turkey was investigated. OTA was detected in 73% of home-made pekmez samples, in 35% of commercial pekmez samples and in 71% of organic pekmez samples. Eleven per cent of the samples had OTA levels higher than 10 µg/l. The highest OTA level (31 µg/l) was detected in organic pekmez. The maximum OTA levels were 15 µg/l and 12 µg/l in home-made and commercial pekmez samples, respectively. Mean OTA levels were 3.5 µg/l, 1.4 µg/l and 9.2 µg/l in home-made, commercial and organic pekmez samples, respectively. Organic pekmez samples and home-made pekmez samples had higher OTA contamination than commercial pekmez samples. Results confirm OTA contamination in grape pekmez samples, indicating that the OTA level in grape pekmez could be a potential risk for consumers.


Assuntos
Contaminação de Alimentos/análise , Ocratoxinas/análise , Vitis/química , Limite de Detecção , Turquia
18.
Angle Orthod ; 84(5): 815-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24552304

RESUMO

OBJECTIVE: To compare the pattern and amount of stress and displacement during maxillary sagittal distraction osteogenesis (DO) between a patient with unilateral cleft lip and palate (UCLP) and a noncleft patient. MATERIALS AND METHODS: Three-dimensional finite element models for both skulls were constructed. Displacements of the surface landmarks and stress distributions in the circummaxillary sutures were analyzed after an anterior displacement of 6 mm was loaded to the elements where the inferior plates of the distractor were assumed to be fixed and were below the Le Fort I osteotomy line. RESULTS: In sagittal plane, more forward movement was found on the noncleft side in the UCLP model (-6.401 mm on cleft side and -6.651 mm on noncleft side for the central incisor region). However, similar amounts of forward movement were seen in the control model. In the vertical plane, a clockwise rotation occurred in the UCLP model, whereas a counterclockwise rotation was seen in the control model. The mathematical UCLP model also showed higher stress values on the sutura nasomaxillaris, frontonasalis, and zygomatiomaxillaris on the cleft side than on the normal side. CONCLUSIONS: Not only did the sagittal distraction forces produce advancement forces at the intermaxillary sutures, but more stress was also present on the sutura nasomaxillaris, sutura frontonasalis, and sutura zygomaticomaxillaris on the cleft side than on the noncleft side.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Análise de Elementos Finitos , Imageamento Tridimensional/métodos , Maxila/cirurgia , Osteogênese por Distração/métodos , Pontos de Referência Anatômicos/patologia , Pontos de Referência Anatômicos/cirurgia , Fenômenos Biomecânicos , Simulação por Computador , Suturas Cranianas/patologia , Suturas Cranianas/cirurgia , Osso Frontal/patologia , Humanos , Masculino , Maxila/anormalidades , Maxila/patologia , Modelos Biológicos , Osso Nasal/patologia , Osteotomia de Le Fort/métodos , Rotação , Estresse Mecânico , Adulto Jovem , Zigoma/patologia
19.
Acta Biomater ; 9(2): 5201-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23072828

RESUMO

Mucus secretion from the body is ubiquitous, and finding materials that resist mucus adhesion is a major technological challenge. Here, using a high throughput platform with photo-induced graft polymerization, we first rapidly synthesized, screened and tested a library of 55 different surfaces from six functional monomer classes to discover porcine intestinal low mucus adhesion surfaces using a 1h static mucus adsorption protocol. From this preliminary screen, two chemistries, a zwitterionic ([2-(acryloyloxy)ethyl] trimethylammonium chloride) and a multiple hydroxyl (N-[tris(hydroxymethyl)methyl]acrylamide) surface, exhibited significantly low mucus adhesion from a Langmuir-type isotherm when exposed to increasing concentrations of mucus for 24 h. Apolar or hydrophobic interactions were likely the dominant attractive forces during mucus binding since many polar or hydrophilic monomers reduced mucus adhesion. Hansen solubility parameters were used to illustrate the importance of monomer polarity and hydrogen bonding in reducing mucus adsorption. For a series of polyethylene glycol (PEG) monomers with changing molecular weight from 144 g mol⁻¹ to 1100 g mol⁻¹, we observed an excellent linear correlation (R²=0.998) between relative amount adsorbed and the distance from a water point in a specialized Hansen solubility parameter plot, emphasizing the role of surface-water interactions for PEG modified surfaces.


Assuntos
Muco/química , Adesividade , Adsorção , Animais , Polimerização , Solubilidade , Sus scrofa , Temperatura , Fatores de Tempo , Raios Ultravioleta
20.
Acta Orthop Traumatol Turc ; 47(6): 417-22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24509222

RESUMO

OBJECTIVE: The aim of this study was to evaluate the mode of failure and biomechanical characteristics of Ti-6Al-4V anchors biomimetically coated with calcium phosphate (CaP) for soft tissue fixation to bone in an animal model. METHODS: The current study included 14 adult New Zealand white rabbits equally divided into two groups. Calcium phosphate-coated Ti-6Al-4V anchors were used in the test group and non-coated Ti-6Al-4V anchors in the control group. A new approach was applied to synthesize the CaP coatings via the biomimetic growth in the Lac-SBF containing Ca(2+) and PO4(3-) ions, Na-lactate and lactic acid (HL). Titanium anchors were implanted into the right tibia, followed by biomechanical tensile strength tests. Histological studies were carried out after removal of anchors (bone-implant surface). RESULTS: The CaP-coated Ti-6Al-4V anchors had significantly higher tensile strength (p=0.003) and displacement values (p=0.004) than the non-coated anchors. Control group scores were higher than those of the test group (14 and 9, respectively) in tensile strength tests. CONCLUSION: The new CaP coating can be used in orthopedic surgery as catalyzer to improve bone ingrowth. We believe that our research will form a model for further research on biomimetic coatings on Ti-6Al-4V substrates.


Assuntos
Líquidos Corporais , Substitutos Ósseos , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Implantes Experimentais , Teste de Materiais , Titânio/química , Ligas , Animais , Materiais Biocompatíveis/química , Modelos Animais de Doenças , Durapatita/química , Ácido Láctico , Teste de Materiais/métodos , Coelhos , Lactato de Sódio , Resistência à Tração
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