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1.
J Arthroplasty ; 38(3): 511-518, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36257506

RESUMO

BACKGROUND: Iliopsoas tendinopathy is a cause of groin pain following total hip arthroplasty (THA). With the anterior approach becoming increasingly popular, our aim was to determine the prevalence of iliopsoas tendinopathy following anterior approach THA, to identify risk factors and to determine an influence on patient-reported outcomes. METHODS: This is a retrospective case-control study of prospectively recorded data on 2,120 primary anterior approach THA (1,815 patients). The diagnosis of iliopsoas tendinopathy was based on (1) persistent postoperative groin pain, triggered by hip flexion; (2) absence of dislocation, infection, loosening, or fracture; and (3) decrease of pain after fluoroscopy-guided iliopsoas tendon sheet injection with xylocaine and corticosteroid. Outcomes included hip reconstruction (inclination/anteversion and leg-length), complication rates, reoperation rates, and patient-reported outcomes including Hip disability and Osteoarthritis Outcome Score. RESULTS: Forty four patients (46 THAs) (2.2%) were diagnosed with iliopsoas tendinopathy. They were younger than patients who did not have iliopsoas tendinopathy (51 years [range, 27-76] versus 62 years [range, 20-90]; P < .001). Logistic regression analyses demonstrated that younger age (P < .001) and presence of a spine fusion (P = .008) (odds ratio 4.6) were the significant predictors of iliopsoas tendinopathy. These patients had lower Hip disability and Osteoarthritis Outcome scores, reported more often low back pain (odds ratio 4.8), and greater trochanter pain (odds ratio 5.4). CONCLUSION: We found an incidence of 2.2% of iliopsoas tendinopathy patients after anterior approach THA that compromised outcomes. Younger age and previous spine fusion were identified as most important risk factors. These patients were 5 times more likely to report low back pain and greater trochanter pain post-THA.


Assuntos
Artroplastia de Quadril , Dor Lombar , Doenças Musculoesqueléticas , Osteoartrite , Tendinopatia , Humanos , Artroplastia de Quadril/efeitos adversos , Estudos Retrospectivos , Dor Lombar/etiologia , Estudos de Casos e Controles , Dor Pós-Operatória/etiologia , Doenças Musculoesqueléticas/complicações , Fatores de Risco , Tendinopatia/epidemiologia , Tendinopatia/etiologia , Tendinopatia/cirurgia , Osteoartrite/complicações , Resultado do Tratamento
2.
Cell Physiol Biochem ; 54(5): 809-824, 2020 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-32857934

RESUMO

BACKGROUND/AIMS: High-molecular-weight advanced glycation end-products (HMW-AGEs) are abundantly present in our Western diet. There is growing evidence reporting that HMW-AGEs contribute to the development of cardiovascular dysfunction in vivo, next to the well-known low-molecular-weight AGEs. The goal of our study is to assess the ultrastructure and function of cardiomyocytes after chronic exposure to HMW-AGEs. A better understanding of underlying mechanisms is essential to create new opportunities for further research on the specific role of HMW-AGEs in the development and progression of cardiovascular diseases. METHODS: Adult male rats were randomly assigned to daily intraperitoneal injection for six weeks with either HMW-AGEs (20 mg/kg/day) or a control solution. Hemodynamic measurements were performed at sacrifice. Single cardiomyocytes from the left ventricle were obtained by enzymatic dissociation through retrograde perfusion of the aorta. Unloaded cell shortening, time to peak and time to 50% relaxation were measured during field stimulation and normalized to diastolic length. L-type Ca2+ current density (ICaL) and steady-state inactivation of ICaL were measured during whole-cell ruptured patch clamp. Myofilament functional properties were measured in membrane-permeabilized cardiomyocytes. Ultrastructural examination of cardiac tissue was performed using electron microscopy. RESULTS: Rats injected with HMW-AGEs displayed in vivo cardiac dysfunction, characterized by significant changes in left ventricular peak rate pressure rise and decline accompanied with an increased heart mass. Single cardiomyocytes isolated from the left ventricle revealed concentric hypertrophy, indicated by the increase in cellular width. Unloaded fractional cell shortening was significantly reduced in cells derived from the HMW-AGEs group and was associated with slower kinetics. Peak L-type Ca2+ current density was significantly decreased in the HMW-AGEs group.L-type Ca2+ channel availability was significantly shifted towards more negative potentials after HMW-AGEs injection. The impact of HMW-AGEs on myofilament function was measured in membrane-permeabilized cardiomyocytes showing a reduction in passive force, maximal Ca2+ activated force and rate of force development. Ultrastructural examination of cardiac tissue demonstrated adverse structural remodeling in HMW-AGEs group characterized by a disruption of the cyto-architecture, a decreased mitochondrial density and altered mitochondrial function. CONCLUSION: Our data indicate that HMW-AGEs induce structural and functional cellular remodeling via a different working mechanism as the well-known LMW-AGEs. Results of our research open the door for new strategies targeting HMW-AGEs to improve cardiac outcome.


Assuntos
Acetaldeído/análogos & derivados , Produtos Finais de Glicação Avançada/efeitos adversos , Miócitos Cardíacos/efeitos dos fármacos , Acetaldeído/efeitos adversos , Acetaldeído/metabolismo , Animais , Aorta/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Diástole/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Cardiopatias/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Masculino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia
3.
J Arthroplasty ; 35(5): 1355-1360, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139189

RESUMO

BACKGROUND: The purpose of this study was to evaluate the alpha defensin qualitative detection (ADLF) sensitivity and specificity as compared with 3 standard classifications in the diagnostic management of chronic prosthetic joint infections. MATERIALS AND METHODS: A multicenter cohort of 136 patients with a painful arthroplasty was classified into either infected or noninfected according to the Musculoskeletal Infection Society (MSIS) score, Infectious Diseases Society of America (IDSA) score, European Bone and Joint Infection Society (EBJIS) score. The sensitivity and specificity of the ADLF test were calculated for each score. Spearman's correlations between all scores were then analyzed, and multiple logistic regression was applied to identify independent variables strongly connected to the prosthetic joint infection probability. RESULTS: The EBJIS score was positive in 68 patients, IDSA score in 50 patients, MSIS score in 41 patients, and ADLF in 40 patients. The ADLF sensitivity was 87.8% compared with MSIS, 70% compared with IDSA, and 55.8% compared with EBJIS. The ADLF specificity was in the range of 94%-97%. A good correlation was observed between synovial fluid cultures and ADLF (r = 0.73). Low to excellent correlations were recorded between ADLF and the EBJIS (r = 0.58), IDSA (r = 0.68), and MSIS (r = 0.84) scores. The synovial fluid's white blood cell count was proven to be the biological test that most influenced the probability of a positive culture (P value: .005). DISCUSSION: The ADLF sensitivity was variable, whereas its specificity was excellent. The EBJIS score results significantly differed from those obtained via cultures, which possibly explains the ADLF low sensitivity compared with that of the EBJIS score.


Assuntos
Artrite Infecciosa , Infecções Relacionadas à Prótese , alfa-Defensinas , Biomarcadores , Humanos , Infecções Relacionadas à Prótese/diagnóstico , Sensibilidade e Especificidade , Líquido Sinovial
4.
J Arthroplasty ; 32(1): 300-303, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27515242

RESUMO

BACKGROUND: The direct anterior approach (DAA) is becoming more popular as the standard surgical approach for primary total hip arthroplasty. However, femoral complications of up to 2.8% have been reported. Therefore, it is important for surgeons to understand the periarticular neurovascular anatomy in order to safely deal with intraoperative complications. METHODS: Anatomic dissections were performed on 20 cadaveric hips. The neurovascular structures anterior to the femur and distal to the intertrochanteric line were dissected and its position was described in relation to anatomic landmarks easily identified through the DAA: anterior superior iliac spine (ASIS), the insertion of the gluteus minimus (GM), and the lesser trochanter (LT). RESULTS: Two clearly distinguishable neurovascular bundles running to the vastus lateralis were seen in 17 of 20 specimens. The average distances to the landmarks were as follows: ASIS-1st bundle = 12.3 cm (range, 9.7-14.5); GM-1st bundle = 3.2 cm (range, 2.2-4); LT-1st bundle = 1.6 cm (range, 0.7-2.8); 1st bundle-2nd bundle = 3.3 cm (range, 1.8-6.1). CONCLUSION: A consistent pattern of 2 clearly distinguishable neurovascular bundles was seen in 85% of the specimens. Knowledge of the position of these neurovascular bundles in relation to the anatomic landmarks makes distal femoral extension of the DAA feasible. Further clinical studies are needed to confirm the safety of the extensile anterior approach.


Assuntos
Artroplastia de Quadril/métodos , Articulação do Quadril/cirurgia , Quadril/cirurgia , Músculo Quadríceps/cirurgia , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Artroplastia de Quadril/efeitos adversos , Cadáver , Estudos de Viabilidade , Feminino , Quadril/irrigação sanguínea , Quadril/inervação , Articulação do Quadril/irrigação sanguínea , Articulação do Quadril/inervação , Humanos , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Músculo Quadríceps/irrigação sanguínea , Músculo Quadríceps/inervação
5.
J Arthroplasty ; 32(7): 2186-2190, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28336251

RESUMO

BACKGROUND: The direct anterior approach (DAA) is becoming more popular as the standard surgical approach for primary total hip arthroplasty. However, it has been associated with an increased incidence of intraoperative femoral fractures in particular during the learning curve. Distal extension of the approach may be needed in case of intraoperative complications. The aim of the present study is to describe the distal extension of the DAA using the femoral interbundle technique. METHODS: A stepwise approach based on a cadaveric study to extend the DAA distally is presented. The interval between the neurovascular bundles running to the vastus lateralis is used to gain access to the femur. Clinical and electromyography results of 5 patients undergoing a revision of the femoral component through an extended anterior approach are reported. RESULTS: In 2 cases, the proximal bundle was exposed whereas in 3 cases the interval between the proximal and distal bundle was developed and cerclage wires were applied around the isthmus of the femur. All fractures had healed at 6 months of follow-up. Four cases had a normal electromyography, and 1 case demonstrated a neuropraxia of a branch to the vastus lateralis. All cases had a 5/5 extension power of the quadriceps muscle clinically. CONCLUSION: The interbundle technique is an alternative way to gain additional exposure of the femur during the DAA and is based on precise knowledge of the periarticular neurovascular structures. This approach can be helpful to safely deal with intraoperative complications such as fractures requiring proximal femoral cerclage wiring during the anterior approach.


Assuntos
Artroplastia de Quadril/métodos , Reoperação/métodos , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Fios Ortopédicos , Feminino , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fêmur/cirurgia , Fixação Interna de Fraturas , Humanos , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Traumatismos dos Nervos Periféricos/etiologia , Músculo Quadríceps/cirurgia
6.
J Arthroplasty ; 32(5): 1553-1559, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28087159

RESUMO

BACKGROUND: The direct anterior approach on a regular operating room table has been reported with low dislocation rates. This might be beneficial for complex primary total hip arthroplasty (THA) such as in patients with cerebral palsy or following femoral or pelvic osteotomies. Extending the approach is often required to overcome problems such as acetabular deformities or severe contractures. METHODS: We retrospectively evaluated the results and complications of 29 patients with 37 complex primary THA in which an extensile approach was used. The extensile approach is described. Functional scores were collected in case the patient was ambulatory independently (n = 17). RESULTS: The average age was 35 years (range 15-85) with a mean follow-up of 39 months (range 12-60). There were 3 (8%) intra-operative and 4 (11%) early post-operative complications (<3 months), of which 3 (8%) were anterior dislocations. Late complications (>3 months) consisted of a fibrous ingrown stem, a socket loosening following a pelvic fracture, and a late hematogenous infection (8%). Seventy-one percent of the complications occurred in the first 18 cases (49%) indicating a learning curve. The mean post-operative Harris Hip Score was 79 (range 56-97). CONCLUSION: Complex THA can be safely conducted through the extensile anterior approach on a regular operating room table with the use of conventional implants, even in cases with a high risk of dislocation.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fêmur/cirurgia , Seguimentos , Luxação do Quadril/etiologia , Luxação do Quadril/prevenção & controle , Humanos , Instabilidade Articular/etiologia , Instabilidade Articular/prevenção & controle , Masculino , Pessoa de Meia-Idade , Mesas Cirúrgicas , Estudos Retrospectivos , Adulto Jovem
7.
Am J Physiol Heart Circ Physiol ; 311(5): H1075-H1090, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27614227

RESUMO

Scarring and remodeling of the left ventricle (LV) after myocardial infarction (MI) results in ischemic cardiomyopathy with reduced contractile function. Regional differences related to persisting ischemia may exist. We investigated the hypothesis that mitochondrial function and structure is altered in the myocardium adjacent to MI with reduced perfusion (MIadjacent) and less so in the remote, nonischemic myocardium (MIremote). We used a pig model of chronic coronary stenosis and MI (n = 13). Functional and perfusion MR imaging 6 wk after intervention showed reduced ejection fraction and increased global wall stress compared with sham-operated animals (Sham; n = 14). Regional strain in MIadjacent was reduced with reduced contractile reserve; in MIremote strain was also reduced but responsive to dobutamine and perfusion was normal compared with Sham. Capillary density was unchanged. Cardiac myocytes isolated from both regions had reduced basal and maximal oxygen consumption rate, as well as through complex I and II, but complex IV activity was unchanged. Reduced respiration was not associated with detectable reduction of mitochondrial density. There was no significant change in AMPK or glucose transporter expression levels, but glycogen content was significantly increased in both MIadjacent and MIremote Glycogen accumulation was predominantly perinuclear; mitochondria in this area were smaller but only in MIadjacent where also subsarcolemmal mitochondria were smaller. In conclusion, after MI reduction of mitochondrial respiration and glycogen accumulation occur in all LV regions suggesting that reduced perfusion does not lead to additional specific changes and that increased hemodynamic load is the major driver for changes in mitochondrial function.


Assuntos
Cardiomiopatias/metabolismo , Mitocôndrias Cardíacas/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Consumo de Oxigênio , Remodelação Ventricular , Proteínas Quinases Ativadas por AMP/genética , Animais , Western Blotting , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Respiração Celular , Cicatriz , Estenose Coronária/complicações , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/genética , Glicogênio/metabolismo , Imageamento por Ressonância Magnética , Microscopia Eletrônica , Microscopia de Fluorescência , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Imagem de Perfusão do Miocárdio , Miócitos Cardíacos/ultraestrutura , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Volume Sistólico , Sus scrofa , Suínos
8.
Adv Exp Med Biol ; 951: 199-235, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27837566

RESUMO

Over the past decade, dental tissues have become an attractive source of mesenchymal stem cells (MSCs). Dental stem cells (DSCs) are not only able to differentiate into adipogenic, chondrogenic and osteogenic lineanges, but an increasing amount of research also pointed out their potential applicability in numerous clinical disorders, such as myocardial infarction, neurodegenerative diseases and diabetes. Together with their multilineage differentiation capacity, their easy availability from extracted third molars makes these stem cells a suitable alternative for bone marrow-derived MSCs. More importantly, DSCs appear to retain their stem cell properties following cryopreservation, a key aspect in their long-term preservation and upscale production. However, the vast number of different cryopreservation protocols makes it difficult to draw definite conclusions regarding the behavior of these stem cells. The routine application and banking of DSCs is also associated with some other pitfalls, such as interdonor variability, cell culture-induced changes and the use of animal-derived culture medium additives. Only thorough assessment of these challenges and the implementation of standardized, GMP procedures will successfully lead to better treatment options for patients who no longer benefit from current stem cell therapies.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Criopreservação/métodos , Polpa Dentária/citologia , Células Secretoras de Insulina/citologia , Miócitos Cardíacos/citologia , Neurônios/citologia , Células-Tronco/citologia , Diferenciação Celular , Proliferação de Células , Crioprotetores/farmacologia , Meios de Cultura/farmacologia , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/fisiologia , Diabetes Mellitus/patologia , Diabetes Mellitus/terapia , Dimetil Sulfóxido/farmacologia , Humanos , Células Secretoras de Insulina/fisiologia , Células Secretoras de Insulina/transplante , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/transplante , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/terapia , Neurônios/fisiologia , Neurônios/transplante , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia
9.
Basic Res Cardiol ; 110(2): 18, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25720581

RESUMO

Postconditioning and cyclosporine A prevent mitochondrial permeability transition pore opening providing cardioprotection during ischemia/reperfusion. Whether microvascular obstruction is affected by these interventions is largely unknown. Pigs subjected to coronary occlusion for 1 h followed by 3 h of reperfusion were assigned to control (n = 8), postconditioning (n = 9) or cyclosporine A intravenous infusion 10-15 min before the end of ischemia (n = 8). Postconditioning was induced by 8 cycles of repeated 30-s balloon inflation and deflation. After 3 h of reperfusion magnetic resonance imaging, triphenyltetrazolium chloride/Evans blue staining and histopathology were performed. Microvascular obstruction (MVO, percentage of gadolinium-hyperenhanced area) was measured early (3 min) and late (12 min) after contrast injection. Infarct size with double staining was smaller in cyclosporine (46.2 ± 3.1%, P = 0.016) and postconditioning pigs (47.6 ± 3.9%, P = 0.008) versus controls (53.8 ± 4.1%). Late MVO was significantly reduced by cyclosporine (13.9 ± 9.6%, P = 0.047) but not postconditioning (23.6 ± 11.7%, P = 0.66) when compared with controls (32.0 ± 16.9%). Myocardial blood flow in the late MVO was improved with cyclosporine versus controls (0.30 ± 0.06 vs 0.21 ± 0.03 ml/g/min, P = 0.002) and was inversely correlated with late-MVO extent (R(2) = 0.93, P < 0.0001). Deterioration of left ventricular ejection fraction (LVEF) between baseline and 3 h of reperfusion was smaller with cyclosporine (-7.9 ± 2.4%, P = 0.008) but not postconditioning (-12.0 ± 5.5%, P = 0.22) when compared with controls (-16.4 ± 5.5%). In the three groups, infarct size (ß = -0.69, P < 0.001) and late MVO (ß = -0.33, P = 0.02) were independent predictors of LVEF deterioration following ischemia/reperfusion (R(2) = 0.73, P < 0.001). Despite both cyclosporine A and postconditioning reduce infarct size, only cyclosporine A infusion had a beneficial effect on microvascular damage and was associated with better preserved LV function when compared with controls.


Assuntos
Ciclosporina/farmacologia , Inibidores Enzimáticos/farmacologia , Pós-Condicionamento Isquêmico/métodos , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Suínos
10.
Europace ; 15(5): 754-60, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23419660

RESUMO

AIMS: Oxidative stress can modulate nitric oxide (NO) signalling pathways. Both pathways have been shown to be involved in the pathophysiology of atrial fibrillation (AF), but data are conflicting. We aimed to characterize the NO-pathway and its relation to oxidative stress in persistent AF in a sheep model. METHODS AND RESULTS: Persistent AF was induced by rapid atrial pacing for a mean of 136.5 ± 21.7 days. Non-stimulated sheep served as controls. Nicotine adenine dinucleotide phosphate (NADPH) oxidase-stimulated superoxide production was significantly increased in the AF group (+51.3 ± 23.2%, P < 0.01). Although there were no changes in mRNA expression of the different NADPH oxidase subunits, the increased activity was associated with markedly increased protein expression of the NADPH oxidase activator, Rac1 (+26 ± 4.6%, P < 0.05). No differences were seen in superoxide dismutase activity, but glutathione peroxidase activity was lower in the AF group. There was a marked accumulation of 3-nitrotyrosine, a biomarker for peroxynitrite, in atrial tissue of AF animals, as demonstrated by immunohistochemical staining and dot blot analysis (+15.6 ± 1.8%, P < 0.05). Expression of atrial NOS3 mRNA was 24.9 ± 4.4% lower in the AF group vs. control (P < 0.05), while NOS1 and 2 were unchanged. Immunoblot analysis revealed no changes in protein expression. Nitrite/nitrate levels were significantly lower during AF (-24.8 ± 5.8%, P < 0.05). CONCLUSION: In a sheep model of persistent AF, NOS3 transcript levels are attenuated and circulating NOx levels decreased. Persistent AF is associated with increased oxidative stress, probably resulting from increased NADPH oxidase activity, without major changes in anti-oxidant capacity of the atrial tissue.


Assuntos
Fibrilação Atrial/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Doença Crônica , Feminino , Ovinos
11.
J Endod ; 49(8): 1058-1072, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37315781

RESUMO

INTRODUCTION: Understanding the healing process of dental pulp after tooth autotransplantation (TAT) and regenerative endodontic treatment (RET) of immature teeth is important both clinically and scientifically. This study aimed to characterize the pattern of dental pulp healing in human teeth that underwent TAT and RET using state-of-the-art imaging techniques. MATERIALS AND METHODS: This study examined 4 human teeth, 2 premolars that underwent TAT, and 2 central incisors that received RET. The premolars were extracted after 1 year (case 1) and 2 years (case 2) due to ankylosis, while the central incisors were extracted after 3 years (cases 3 and 4) for orthodontic reasons. Nanofocus x-ray computed tomography was used to image the samples before being processed for histological and immunohistochemical analysis. Laser scanning confocal second harmonic generation imaging (SHG) was used to examine the patterns of collagen deposition. A maturity-matched premolar was included as a negative control for the histological and SHG analysis. RESULTS: Analysis of the 4 cases revealed different patterns of dental pulp healing. Similarities were observed in the progressive obliteration of the root canal space. However, a striking loss of typical pulpal architecture was observed in the TAT cases, while a pulp-like tissue was observed in one of the RET cases. Odontoblast-like cells were observed in cases 1 and 3. CONCLUSIONS: This study provided insights into the patterns of dental pulp healing after TAT and RET. The SHG imaging sheds light on the patterns of collagen deposition during reparative dentin formation.


Assuntos
Polpa Dentária , Endodontia Regenerativa , Humanos , Polpa Dentária/diagnóstico por imagem , Regeneração , Endodontia Regenerativa/métodos , Transplante Autólogo , Necrose da Polpa Dentária/diagnóstico por imagem , Necrose da Polpa Dentária/terapia , Colágeno , Imagem Multimodal
12.
iScience ; 25(2): 103822, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35198884

RESUMO

Age-related fibrosis in the left ventricle (LV) has been mainly studied in animals by assessing collagen content. Using second-harmonic generation microscopy and image processing, we evaluated amount, aggregation and spatial distribution of LV collagen in young to old pigs, and middle-age and elder living donors. All collagen features increased when comparing adult and old pigs with young ones, but not when comparing adult with old pigs or middle-age with elder individuals. Remarkably, all collagen parameters strongly correlated with lipofuscin, a biological age marker, in humans. By building patient-specific models of human ventricular tissue electrophysiology, we confirmed that amount and organization of fibrosis modulated arrhythmia vulnerability, and that distribution should be accounted for arrhythmia risk assessment. In conclusion, we characterize the age-associated changes in LV collagen and its potential implications for ventricular arrhythmia development. Consistency between pig and human results substantiate the pig as a relevant model of age-related LV collagen dynamics.

14.
Circ Res ; 105(9): 876-85, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-19762679

RESUMO

RATIONALE: Persistent atrial fibrillation (AF) has been associated with structural and electric remodeling and reduced contractile function. OBJECTIVE: To unravel mechanisms underlying reduced sarcoplasmic reticulum (SR) Ca(2+) release in persistent AF. METHODS: We studied cell shortening, membrane currents, and [Ca(2+)](i) in right atrial myocytes isolated from sheep with persistent AF (duration 129+/-39 days, N=16), compared to matched control animals (N=21). T-tubule density, ryanodine receptor (RyR) distribution, and local [Ca(2+)](i) transients were examined in confocal imaging. RESULTS: Myocyte shortening and underlying [Ca(2+)](i) transients were profoundly reduced in AF (by 54.8% and 62%, P<0.01). This reduced cell shortening could be corrected by increasing [Ca(2+)](i). SR Ca(2+) content was not different. Calculated fractional SR Ca(2+) release was reduced in AF (by 20.6%, P<0.05). Peak Ca(2+) current density was modestly decreased (by 23.9%, P<0.01). T-tubules were present in the control atrial myocytes at low density and strongly reduced in AF (by 45%, P<0.01), whereas the regular distribution of RyR was unchanged. Synchrony of SR Ca(2+) release in AF was significantly reduced with increased areas of delayed Ca(2+) release. Propagation between RyR was unaffected but Ca(2+) release at subsarcolemmal sites was reduced. Rate of Ca(2+) extrusion by Na(+)/Ca(2+) exchanger was increased. CONCLUSIONS: In persistent AF, reduced SR Ca(2+) release despite preserved SR Ca(2+) content is a major factor in contractile dysfunction. Fewer Ca(2+) channel-RyR couplings and reduced efficiency of the coupling at subsarcolemmal sites, possibly related to increased Na(+)/Ca(2+) exchanger, underlie the reduction in Ca(2+) release.


Assuntos
Fibrilação Atrial/metabolismo , Função do Átrio Direito , Sinalização do Cálcio , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , Citoesqueleto de Actina/metabolismo , Animais , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Canais de Cálcio Tipo L/metabolismo , Modelos Animais de Doenças , Técnicas Eletrofisiológicas Cardíacas , Feminino , Glicogênio/metabolismo , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Potenciais da Membrana , Miócitos Cardíacos/ultraestrutura , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Sarcolema/metabolismo , Retículo Sarcoplasmático/ultraestrutura , Ovinos , Trocador de Sódio e Cálcio/metabolismo , Fatores de Tempo
15.
Front Cell Dev Biol ; 9: 665600, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026757

RESUMO

The apical papilla is a stem cell rich tissue located at the base of the developing dental root and is responsible for the progressive elongation and maturation of the root. The multipotent stem cells of the apical papilla (SCAP) are extensively studied in cell culture since they demonstrate a high capacity for osteogenic, adipogenic, and chondrogenic differentiation and are thus an attractive stem cell source for stem cell-based therapies. Currently, only few studies are dedicated to determining the role of the apical papilla in dental root development. In this review, we will focus on the architecture of the apical papilla and describe the specific SCAP signaling pathways involved in root maturation. Furthermore, we will explore the heterogeneity of the SCAP phenotype within the tissue and determine their micro-environmental interaction. Understanding the mechanism of postnatal dental root growth could further aid in developing novel strategies in dental root regeneration.

16.
Bone Joint J ; 103-B(2): 321-328, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33517727

RESUMO

AIMS: Optimal exposure through the direct anterior approach (DAA) for total hip arthroplasty (THA) conducted on a regular operating theatre table is achieved with a standardized capsular releasing sequence in which the anterior capsule can be preserved or resected. We hypothesized that clinical outcomes and implant positioning would not be different in case a capsular sparing (CS) technique would be compared to capsular resection (CR). METHODS: In this prospective trial, 219 hips in 190 patients were randomized to either the CS (n = 104) or CR (n = 115) cohort. In the CS cohort, a medial based anterior flap was created and sutured back in place at the end of the procedure. The anterior capsule was resected in the CR cohort. Primary outcome was defined as the difference in patient-reported outcome measures (PROMs) after one year. PROMs (Harris Hip Score (HHS), Hip disability and Osteoarthritis Outcome Score (HOOS), and Short Form 36 Item Health Survey (SF-36)) were collected preoperatively and one year postoperatively. Radiological parameters were analyzed to assess implant positioning and implant ingrowth. Adverse events were monitored. RESULTS: At one year, there was no difference in HSS (p = 0.728), HOOS (Activity Daily Life, p = 0.347; Pain, p = 0.982; Quality of Life, p = 0.653; Sport, p = 0.994; Symptom, p = 0.459), or SF-36 (p = 0.338). Acetabular component inclination (p = 0.276) and anteversion (p = 0.392) as well as femoral component alignment (p = 0.351) were similar in both groups. There were no dislocations, readmissions, or reoperations in either group. The incidence of psoas tendinitis was six cases in the CS cohort (6%) and six cases in the CR cohort (5%) (p = 0.631). CONCLUSION: No clinical differences were found between resection or preservation of the anterior capsule when performing a primary THA through the DAA on a regular theatre table. In case of limited visibility during the learning curve, it might be advisable to resect a part of the anterior capsule. Cite this article: Bone Joint J 2021;103-B(2):321-328.


Assuntos
Artroplastia de Quadril/métodos , Cápsula Articular/cirurgia , Osteoartrite do Quadril/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Resultado do Tratamento
17.
Orthopedics ; 43(4): e299-e305, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32501521

RESUMO

Impaired abductor function of the hip following severe abductor deficiencies can be devastating for functionality and quality of life. Recently, gluteus maximus transfer has been proposed as a solution to these difficult problems. However, outcome results are sparse. The aim of this study was to evaluate the effects of gluteus maximus transfer on improvement of pain, disability, and quality of life in patients with severe hip abductor deficiencies. Gluteus maximus transfer was performed in 16 patients with severe disruption of the abductor muscles of the hip. Data were collected preoperatively and at 6 weeks, 3 and 6 months, and 1 to 2 years after surgery. The measurements pertained to complications, healing of the flap based on magnetic resonance imaging (MRI) findings (in 10 patients), evaluation of Trendelenburg gait and sign, and patient-reported outcome measures of pain, disability, and quality of life. Preoperatively, all patients had a positive Trendelenburg sign and reported severe pain at the level of the greater trochanter. At a mean follow-up of 20 months, the Trendelenburg sign was negative in 7 patients and the Trendelenburg gait had disappeared in 7 patients. There was an improvement in patient-reported outcome measures but not to a significant level except for the pain subscores. Two patients had a postoperative seroma that resulted in a visible bump on the lateral side. Seven of 10 repairs with MRI follow-up showed perfect ingrowth on MRI without signs of rerupture. Gluteus maximus transfer for abductor deficiency of the hip may be effective for pain relief and functional improvements. Most patients showed an improved quality of life but were not completely pain free. [Orthopedics. 2020;43(4):e299-e305.].


Assuntos
Nádegas/cirurgia , Quadril/cirurgia , Músculo Esquelético/cirurgia , Doenças Musculoesqueléticas/cirurgia , Procedimentos Ortopédicos/métodos , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Idoso , Feminino , Seguimentos , Marcha , Quadril/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento
18.
Sci Rep ; 10(1): 12220, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699285

RESUMO

Growing evidence supports the role of advanced glycation end products (AGEs) in the development of diabetic vascular complications and cardiovascular diseases (CVDs). We have shown that high-molecular-weight AGEs (HMW-AGEs), present in our Western diet, impair cardiac function. Whether HMW-AGEs affect vascular function remains unknown. In this study, we aimed to investigate the impact of chronic HMW-AGEs exposure on vascular function and structure. Adult male Sprague Dawley rats were daily injected with HMW-AGEs or control solution for 6 weeks. HMW-AGEs animals showed intracardiac pressure overload, characterized by increased systolic and mean pressures. The contraction response to PE was increased in aortic rings from the HMW-AGEs group. Relaxation in response to ACh, but not SNP, was impaired by HMW-AGEs. This was associated with reduced plasma cyclic GMP levels. SOD restored ACh-induced relaxation of HMW-AGEs animals to control levels, accompanied by a reduced half-maximal effective dose (EC50). Finally, collagen deposition and intima-media thickness of the aortic vessel wall were increased with HMW-AGEs. Our data demonstrate that chronic HMW-AGEs exposure causes adverse vascular remodelling. This is characterised by disturbed vasomotor function due to increased oxidative stress and structural changes in the aorta, suggesting an important contribution of HMW-AGEs in the development of CVDs.


Assuntos
Acetaldeído/análogos & derivados , Aorta/metabolismo , Aorta/fisiopatologia , Pressão Sanguínea/fisiologia , Coração/fisiopatologia , Remodelação Vascular/fisiologia , Acetaldeído/metabolismo , Acetilcolina/farmacologia , Animais , Aorta/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Colágeno/metabolismo , GMP Cíclico/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Produtos Finais de Glicação Avançada/metabolismo , Coração/efeitos dos fármacos , Masculino , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Remodelação Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
19.
Front Pharmacol ; 11: 268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231569

RESUMO

BACKGROUND AND PURPOSE: Up to 50-60% of all cancer patients receive radiotherapy as part of their treatment strategy. However, the mechanisms accounting for increased vascular risks after irradiation are not completely understood. Mitochondrial dysfunction has been identified as a potential cause of radiation-induced atherosclerosis. MATERIALS AND METHODS: Assays for apoptosis, cellular metabolism, mitochondrial DNA content, functionality and morphology were used to compare the response of endothelial cells to a single 2 Gy dose of X-rays under basal conditions or after pharmacological treatments that either reduced (EtBr) or increased (rosiglitazone) mitochondrial content. RESULTS: Exposure to ionizing radiation caused a persistent reduction in mitochondrial content of endothelial cells. Pharmacological reduction of mitochondrial DNA content rendered endothelial cells more vulnerable to radiation-induced apoptosis, whereas rosiglitazone treatment increased oxidative metabolism and redox state and decreased the levels of apoptosis after irradiation. CONCLUSION: Pre-existing mitochondrial damage sensitizes endothelial cells to ionizing radiation-induced mitochondrial dysfunction. Rosiglitazone protects endothelial cells from the detrimental effects of radiation exposure on mitochondrial metabolism and oxidative stress. Thus, our findings indicate that rosiglitazone may have potential value as prophylactic for radiation-induced atherosclerosis.

20.
J Cell Mol Med ; 13(5): 896-908, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19538254

RESUMO

Differentiation of foetal cardiomyocytes is accompanied by sequential actin isoform expression, i.e. down-regulation of the 'embryonic' alpha smooth muscle actin, followed by an up-regulation of alpha skeletal actin (alphaSKA) and a final predominant expression of alpha cardiac actin (alphaCA). Our objective was to detect whether re-expression of alphaSKA occurred during cardiomyocyte dedifferentiation, a phenomenon that has been observed in different pathologies characterized by myocardial dysfunction. Immunohistochemistry of alphaCA, alphaSKA and cardiotin was performed on left ventricle biopsies from human patients after coronary bypass surgery. Furthermore, actin isoform expression was investigated in left ventricle samples of rabbit hearts suffering from pressure- and volume-overload and in adult rabbit ventricular cardiomyocytes during dedifferentiation in vitro. Atrial goat samples up to 16 weeks of sustained atrial fibrillation (AF) were studied ultrastructurally and were immunostained for alphaCA and alphaSKA. Up-regulation of alphaSKA was observed in human ventricular cardiomyocytes showing down-regulation of alphaCA and cardiotin. A patchy re-expression pattern of alphaSKA was observed in rabbit left ventricular tissue subjected to pressure- and volume-overload. Dedifferentiating cardiomyocytes in vitro revealed a degradation of the contractile apparatus and local re-expression of alphaSKA. Comparable alphaSKA staining patterns were found in several areas of atrial goat tissue during 16 weeks of AF together with a progressive glycogen accumulation at the same time intervals. The expression of alphaSKA in adult dedifferentiating cardiomyocytes, in combination with PAS-positive glycogen and decreased cardiotin expression, offers an additional tool in the evaluation of myocardial dysfunction and indicates major changes in the contractile properties of these cells.


Assuntos
Actinas/metabolismo , Desdiferenciação Celular/fisiologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Actinina/metabolismo , Animais , Insuficiência da Valva Aórtica/metabolismo , Insuficiência da Valva Aórtica/patologia , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Biomarcadores/metabolismo , Células Cultivadas , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Regulação para Baixo/fisiologia , Feminino , Glicogênio/metabolismo , Cabras , Humanos , Miocárdio Atordoado/metabolismo , Miocárdio Atordoado/patologia , Isoformas de Proteínas/metabolismo , Coelhos , Regulação para Cima/fisiologia
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