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1.
Arch Phys Med Rehabil ; 105(2): 258-267, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37499853

RESUMEN

OBJECTIVE: Investigate the effects of multisensory training with and without the anchor system on breast cancer survivors' postural balance and self-efficacy of falls. DESIGN: Clinical randomized, controlled, and crossover trial. SETTING: Teaching, Research, and Assistance Center in Mastectomized Rehabilitation. PARTICIPANTS: Eighty breast cancer survivors homogeneously distributed in the groups of adults and elderly affected, or not, by lymphedema. INTERVENTIONS: Participants were randomized to multisensory training with and without the anchor system involving 3 sessions per week for 12 weeks. After the 4-week washout period, the remaining therapeutic intervention was applied. MAIN OUTCOME MEASURES: The primary outcome was semi-static and dynamic balance as evaluated by baropodometry and Mini Balance Evaluation Systems Test, and the secondary outcome was self-efficacy of the fall episode as assessed by Falls Efficacy Scale - International in the pre-, post-immediate, and 4-week follow-up period. RESULTS: Both therapeutic interventions caused positive and significant effects on postural balance and self-efficacy of falls in the immediate period. The multisensory training with the anchor system induced significant functional retention in the short term, related to the clinical effect of small to moderate variation. CONCLUSIONS: Multisensory training with the anchor system is convenient for postural balance and self-efficacy for falls, regardless of age and upper limb volume, for breast cancer survivors.


Asunto(s)
Neoplasias de la Mama , Terapia por Ejercicio , Anciano , Femenino , Humanos , Estudios Cruzados , Modalidades de Fisioterapia , Equilibrio Postural , Adulto
2.
Int J Mol Sci ; 24(21)2023 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-37958710

RESUMEN

Bone lesions have the capacity for regeneration under normal conditions of the bone metabolism process. However, due to the increasing incidence of major traumas and diseases that cause bone-mineral deficiency, such as osteoporosis, scaffolds are needed that can assist in the bone regeneration process. Currently, natural polymeric scaffolds and bioactive nanoparticles stand out. Therefore, the objective of the study was to evaluate the osteoregenerative potential in tibiae of healthy and ovariectomized rats using mineralized collagen and nanohydroxyapatite (nHA) scaffolds associated with elastin. The in-vivo experimental study was performed with 60 20-week-old Wistar rats, distributed into non-ovariectomized (NO) and ovariectomized (O) groups, as follows: Controls (G1-NO-C and G4-O-C); Collagen with nHA scaffold (G2-NO-MSH and G5-O-MSH); and Collagen with nHA and elastin scaffold (G3-NO-MSHC and G6-O-MSHC). The animals were euthanized 6 weeks after surgery and the samples were analyzed by macroscopy, radiology, and histomorphometry. ANOVA and Tukey tests were performed with a 95% CI and a significance index of p < 0.05. In the histological analyses, it was possible to observe new bone formed with an organized and compact morphology that was rich in osteocytes and with maturity characteristics. This is compatible with osteoconductivity in both matrices (MSH and MSHC) in rats with normal conditions of bone metabolism and with gonadal deficiency. Furthermore, they demonstrated superior osteogenic potential when compared to control groups. There was no significant difference in the rate of new bone formation between the scaffolds. Ovariectomy did not exacerbate the immune response but negatively influenced the bone-defect repair process.


Asunto(s)
Durapatita , Elastina , Femenino , Ratas , Animales , Humanos , Ratas Wistar , Colágeno , Osteogénesis , Regeneración Ósea , Ovariectomía , Andamios del Tejido , Ingeniería de Tejidos
3.
Molecules ; 26(6)2021 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-33805847

RESUMEN

Autologous bone grafts, used mainly in extensive bone loss, are considered the gold standard treatment in regenerative medicine, but still have limitations mainly in relation to the amount of bone available, donor area, morbidity and creation of additional surgical area. This fact encourages tissue engineering in relation to the need to develop new biomaterials, from sources other than the individual himself. Therefore, the present study aimed to investigate the effects of an elastin and collagen matrix on the bone repair process in critical size defects in rat calvaria. The animals (Wistar rats, n = 30) were submitted to a surgical procedure to create the bone defect and were divided into three groups: Control Group (CG, n = 10), defects filled with blood clot; E24/37 Group (E24/37, n = 10), defects filled with bovine elastin matrix hydrolyzed for 24 h at 37 °C and C24/25 Group (C24/25, n = 10), defects filled with porcine collagen matrix hydrolyzed for 24 h at 25 °C. Macroscopic and radiographic analyses demonstrated the absence of inflammatory signs and infection. Microtomographical 2D and 3D images showed centripetal bone growth and restricted margins of the bone defect. Histologically, the images confirmed the pattern of bone deposition at the margins of the remaining bone and without complete closure by bone tissue. In the morphometric analysis, the groups E24/37 and C24/25 (13.68 ± 1.44; 53.20 ± 4.47, respectively) showed statistically significant differences in relation to the CG (5.86 ± 2.87). It was concluded that the matrices used as scaffolds are biocompatible and increase the formation of new bone in a critical size defect, with greater formation in the polymer derived from the intestinal serous layer of porcine origin (C24/25).


Asunto(s)
Biopolímeros/química , Regeneración Ósea/fisiología , Andamios del Tejido/química , Animales , Materiales Biocompatibles/química , Birrefringencia , Matriz Ósea/química , Matriz Ósea/fisiología , Remodelación Ósea/fisiología , Sustitutos de Huesos/química , Calcificación Fisiológica/fisiología , Bovinos , Colágeno/química , Colágeno/metabolismo , Elastina/química , Elastina/metabolismo , Imagenología Tridimensional , Masculino , Ensayo de Materiales , Ratas , Ratas Wistar , Cráneo/diagnóstico por imagen , Cráneo/lesiones , Cráneo/fisiología , Porcinos , Ingeniería de Tejidos/métodos , Microtomografía por Rayos X
4.
PLoS One ; 15(4): e0231112, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32310975

RESUMEN

Tissue engineering represents a promising alternative for reconstructive surgical procedures especially for the repair of bone defects that do not regenerate spontaneously. The present study aimed to evaluate the effects of the elastin matrix (E24/50 and E96/37) incorporated with hydroxyapatite (HA) or morphogenetic protein (BMP) on the bone repair process in the distal metaphysis of rat femur. The groups were: control group (CG), hydrolyzed elastin matrix at 50°C/24h (E24/50), E24/50 + HA (E24/50/HA), E24/50 + BMP (E24/50/BMP), hydrolyzed elastin matrix at 37°C/96h (E96/37), E96/37 + HA (E96/37/HA), E96/37 + BMP (E96/37/BMP). Macroscopic and radiographic analyses showed longitudinal integrity of the femur in all groups without fractures or bone deformities. Microtomographically, all groups demonstrated partial closure by mineralized tissue except for the E96/37/HA group with hyperdense thin bridge formation interconnecting the edges of the ruptured cortical. Histologically, there was no complete cortical recovery in any group, but partial closure with trabecular bone. In defects filled with biomaterials, no chronic inflammatory response or foreign body type was observed. The mean volume of new bone formed was statistically significant higher in the E96/37/HA and E24/50 groups (71.28 ± 4.26 and 66.40 ± 3.69, respectively) than all the others. In the confocal analysis, it was observed that all groups presented new bone markings formed during the experimental period, being less evident in the CG group. Von Kossa staining revealed intense calcium deposits distributed in all groups. Qualitative analysis of collagen fibers under polarized light showed a predominance of red-orange birefringence in the newly regenerated bone with no difference between groups. It was concluded that the E24/50 and E96/37/HA groups promoted, with greater speed, the bone repair process in the distal metaphysis of rat femur.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Fémur/lesiones , Osteogénesis/efectos de los fármacos , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Proteínas Morfogenéticas Óseas/administración & dosificación , Modelos Animales de Enfermedad , Durapatita/administración & dosificación , Elastina/administración & dosificación , Fémur/diagnóstico por imagen , Fémur/efectos de los fármacos , Humanos , Masculino , Ratas , Factores de Tiempo , Microtomografía por Rayos X
5.
Am J Transl Res ; 11(8): 5261-5271, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31497239

RESUMEN

The use of biomaterials in medical and dental areas has become increasingly important due to the need to restore areas with bone loss or defects. This study analyzed the use of a new elastin polymer matrix combined with Bone Morphogenetic Protein for the repair of cranial defects in rats. Thirty rats were divided into five groups: control (C) defect without graft, E24 (defect filled with elastin matrix submitted to alkaline hydrolysis at 50°C for 24 h), E24/BMP (defect filled with elastin matrix treated at 50°C for 24 h plus BMP), E96 (defect filled with elastin matrix treated at 37°C for 96 h) and E96/BMP (defect filled with elastin matrix treated at 37°C for 96 h plus BMP). The animals were killed after 6 weeks. In the histological and microtomographic analysis, all groups showed bone growth from the defect margins remaining in this region without a marked inflammatory process, but in the E96/BMP group the lamellae were thicker and the collagen fibers more organized. Histometrically, the same group presented higher percentage of new formation (43.25 ± 3.72) in relation to the other groups. It was concluded that the support and delivery system formed by the elastin matrix associated with BMPs had a positive effect on the bone repair process.

6.
Head Neck ; 30(1): 85-92, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17685455

RESUMEN

BACKGROUND: This study aims to compare the alterations in the methylation profiles of E-cadherin in oral cancer, especially in tumors with lowest metatastic potential. METHODS: Nine oral verrucous carcinomas (VCs), 20 oral well-differentiated squamous cell carcinomas without lymph node involvement (SCC-pN0), and 17 with lymph node involvement (SCC-pN+) were analyzed using methylation-specific polymerase chain reaction and immunohistochemical expression of E-cadherin gene. RESULTS: The immunohistochemical expression of E-cadherin in VC was significantly higher (p = .016) when compared with SCC-pN0 and SCC-pN+ groups. The E-cadherin gene methylation was not correlated with its abnormal immunohistochemical expression in VC and SCC-pN0. All tumors of the SCC-pN+ group with unmethylated E-cadherin gene showed significant loss of E-cadherin immunoexpression (p = .044). CONCLUSIONS: The E-cadherin gene methylation presence in tumors with lowest invasive and metastatic potential, such as VC, suggests the early involvement of this epigenetic event in the multistep progression of the oral carcinogenesis.


Asunto(s)
Cadherinas/genética , Islas de CpG/genética , Metilación de ADN , Neoplasias de la Boca/genética , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/genética , Carcinoma Verrugoso/genética , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
7.
Clin Oral Investig ; 10(3): 205-9, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16738900

RESUMEN

Oral verrucous carcinoma (OVC) is a rare variant of squamous cell carcinoma with a characteristic morphology and specific behavior. To date, few studies are available focusing the prevalence and clinicopathologic features of the oral verrucous carcinoma in Brazilian population. A total of 3,500 primary oral well-differentiated squamous cell carcinoma surgically excised in the A.C. Camargo Cancer Hospital and Amaral Carvalho Cancer Hospital, Brazil, from 1980 to 2000 were retrospectively reviewed. Twenty cases of verrucous carcinomas were identified, most of them occurring in older male with age above the sixth decade, the sites frequently affected being the lower lip and the hard palate. Microscopically, the tumor showed a heavily keratinized lesion with compressive invasion pattern, little atypia, and free surgical margins. The local recurrence was verified in 38.5% of the patients with oral verrucous carcinoma; however, regional recurrence and distant metastasis were not verified. The results suggest that, although it is less frequent and with excellent prognosis, the verrucous carcinoma presents a potential for local recurrence that should be considered during the surgical planning of this neoplasm in the oral cavity.


Asunto(s)
Carcinoma Verrugoso/epidemiología , Carcinoma Verrugoso/patología , Neoplasias de la Boca/epidemiología , Neoplasias de la Boca/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Carcinoma Verrugoso/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/patología , Neoplasias de la Boca/cirugía , Recurrencia Local de Neoplasia , Prevalencia , Pronóstico , Estudios Retrospectivos , Factores Sexuales
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(2 Pt 2): 026201, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14525078

RESUMEN

We study the origins of period doubling and chaos in the driven series resistor-inductor-varactor diode (RLD) nonlinear resonant circuit. We find that resonators driven at frequencies much higher than the diode reverse recovery rate do not show period doubling. Models of chaos based on the nonlinear capacitance of the varactor diode display a reverse-recovery-like effect, and this effect strongly resembles reverse recovery of real diodes. We find for the first time that in addition to the known dependence of the reverse recovery time on past current maxima, there are also important nonlinear dependencies on pulse frequency, duty cycle, and dc voltage bias. Similar nonlinearities are present in the nonlinear capacitance models of these diodes. We conclude that a history-dependent and nonlinear reverse-recovery time is an essential ingredient for chaotic behavior of this circuit, and demonstrate for the first time that all major competing models have this effect, either explicitly or implicitly. Besides unifying the two major models of RLD chaos, our work reveals that the nonlinearities of the reverse-recovery time must be included for a complete understanding of period doubling and chaos in this circuit.

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