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1.
Psychol Med ; 45(9): 1999-2012, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25678201

RESUMEN

BACKGROUND: Maternal depression in the pre- and postpartum period may set women on a course of chronic depressive symptoms. Little is known about predictors of persistently elevated depressive symptoms in mothers from pregnancy onwards. The aims of this study are to determine maternal depression trajectories from pregnancy to the child's fifth birthday and identify associated risk factors. METHOD: Mothers (N = 1807) from the EDEN mother-child birth cohort study based in France (2003-2011) were followed from 24-28 weeks of pregnancy to their child's fifth birthday. Maternal depression trajectories were determined with a semi-parametric group-based modelling strategy. Sociodemographic, psychosocial and psychiatric predictors were explored for their association with trajectory class membership. RESULTS: Five trajectories of maternal symptoms of depression from pregnancy onwards were identified: no symptoms (60.2%); persistent intermediate-level depressive symptoms (25.2%); persistent high depressive symptoms (5.0%); high symptoms in pregnancy only (4.7%); high symptoms in the child's preschool period only (4.9%). Socio-demographic predictors associated with persistent depression were non-French origin; psychosocial predictors were childhood adversities, life events during pregnancy and work overinvestment; psychiatric predictors were previous mental health problems, psychological help, and high anxiety during pregnancy. CONCLUSIONS: Persistent depression in mothers of young children is associated to several risk factors present prior to or during pregnancy, notably anxiety. These characteristics precede depression trajectories and offer a possible entry point to enhance mother's mental health and reduce its burden on children.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles/psicología , Ansiedad/psicología , Depresión Posparto/psicología , Depresión/psicología , Madres/psicología , Complicaciones del Embarazo/psicología , Estrés Psicológico/psicología , Trastornos Relacionados con Sustancias/psicología , Adulto , Estudios de Cohortes , Progresión de la Enfermedad , Empleo , Femenino , Francia , Humanos , Acontecimientos que Cambian la Vida , Estudios Longitudinales , Embarazo , Estudios Prospectivos , Factores de Riesgo , Apoyo Social
2.
Acta Psychiatr Scand ; 131(4): 307-17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25289581

RESUMEN

OBJECTIVE: To examine whether non-psychiatric hospitalizations rates were higher in those with mental disorders. METHOD: In a cohort of 15,811 employees, aged 35-50 years in 1989, mental disorder status was defined from 1989 to 2000. Hospitalizations for all-causes, myocardial infarction (MI), stroke, and cancer, were recorded yearly from 2001 to 2011. Negative binomial regression models were used to estimate hospitalization rates over the follow-up. RESULTS: After controlling for baseline sociodemographic factors, health-related behaviors, self-rated health, and self-reported medical conditions, participants with a mental disorder had significantly higher rates of all-cause hospitalization [incidence rate ratio, IRR=1.20 (95%, 1.14-1.26)], as well as hospitalization due to MI [IRR=1.44 (95%, 1.12-1.85)]. For stroke, the IRR did not reach statistical significance [IRR=1.37 (95%, 0.95-1.99)] and there was no association with cancer [IRR=1.01 (95%, 0.86-1.19)]. A similar trend was observed when mental disorders groups were considered (no mental disorder, depressive disorder, mental disorders due to psychoactive substance use, other mental disorders, mixed mental disorders, and severe mental disorder). CONCLUSION: In this prospective cohort of employees with stable employment as well as universal access to healthcare, we found participants with mental disorders to have higher rates of non-psychiatric hospitalizations.


Asunto(s)
Hospitalización/estadística & datos numéricos , Trastornos Mentales/complicaciones , Adulto , Femenino , Humanos , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Neoplasias/diagnóstico , Neoplasias/epidemiología , Servicios de Salud del Trabajador , Estudios Prospectivos , Factores de Riesgo , Factores Socioeconómicos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología
3.
J Affect Disord ; 321: 16-27, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36272461

RESUMEN

BACKGROUND: During the perinatal period, women's perceived quality of life (QOL) may be altered due to physiological, psychological, and bodily changes, as well as changes in family functioning. OBJECTIVES: to explore in a sample of women from the general population, the associations between physical and mental QOL at 1 year post-partum and i) pregnancy social support, demographic, socioeconomic, medical and child health-related factors, paternal and maternal psychological characteristics at 2 months and 1 year post-partum, ii) antenatal preventive measures (early prenatal interview/antenatal classes). METHODS: We used data from the "French Longitudinal Study since Childhood" (ELFE), a representative cohort of children and their parents followed from birth to adulthood. Data were collected from mothers in the maternity ward, at 2 months and 1-year post-partum. QOL was assessed using the SF12 physical (PCS-12) and mental (MCS-12) subscales. RESULTS: Women with both low PCS-12 and MCS-12 scores were more likely to have high maternal age and to experience psychological difficulties during pregnancy. They also had more frequent PNDS, quarrels with insults within the couple, low sleep time at 2 months postpartum, and more frequently received psychological, social and child caregiver support, and were more often housewives or students at 1-year post-partum. Others factors are specific for low PCS-12 or MCS-12. There was no association with antenatal preventive measure and QOL at 1-year post-partum. CONCLUSION: Factors influencing maternal QOL are multiple and multidimensional and can mostly be identified during the ante or early postnatal period. A graduated and coordinated preventive and curative pathway would improve women's health. An ecosystemic approach to pregnancy and the perinatal period could help preventing the negative effects of environment on mothers and thus infants during the "1000-day period".


Asunto(s)
Salud Mental , Calidad de Vida , Humanos , Lactante , Niño , Femenino , Embarazo , Adulto , Calidad de Vida/psicología , Estudios Longitudinales , Madres/psicología , Parto
4.
Behav Res Ther ; 159: 104226, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36410111

RESUMEN

Mitigating the COVID-19 related disruptions in mental health care services is crucial in a time of increased mental health disorders. Numerous reviews have been conducted on the process of implementing technology-based mental health care during the pandemic. The research question of this umbrella review was to examine what the impact of COVID-19 was on access and delivery of mental health services and how mental health services have changed during the pandemic. A systematic search for systematic reviews and meta-analyses was conducted up to August 12, 2022, and 38 systematic reviews were identified. Main disruptions during COVID-19 were reduced access to outpatient mental health care and reduced admissions and earlier discharge from inpatient care. In response, synchronous telemental health tools such as videoconferencing were used to provide remote care similar to pre-COVID care, and to a lesser extent asynchronous virtual mental health tools such as apps. Implementation of synchronous tools were facilitated by time-efficiency and flexibility during the pandemic but there was a lack of accessibility for specific vulnerable populations. Main barriers among practitioners and patients to use digital mental health tools were poor technological literacy, particularly when preexisting inequalities existed, and beliefs about reduced therapeutic alliance particularly in case of severe mental disorders. Absence of organizational support for technological implementation of digital mental health interventions due to inadequate IT infrastructure, lack of funding, as well as lack of privacy and safety, challenged implementation during COVID-19. Reviews were of low to moderate quality, covered heterogeneously designed primary studies and lacked findings of implementation in low- and middle-income countries. These gaps in the evidence were particularly prevalent in studies conducted early in the pandemic. This umbrella review shows that during the COVID-19 pandemic, practitioners and mental health care institutions mainly used synchronous telemental health tools, and to a lesser degree asynchronous tools to enable continued access to mental health care for patients. Numerous barriers to these tools were identified, and call for further improvements. In addition, more high quality research into comparative effectiveness and working mechanisms may improve scalability of mental health care in general and in future infectious disease outbreaks.


Asunto(s)
COVID-19 , Humanos , Salud Mental , Pandemias , Revisiones Sistemáticas como Asunto , Comunicación por Videoconferencia
5.
J Affect Disord ; 293: 238-244, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34217961

RESUMEN

BACKGROUND: Given the high incidence of perinatal maternal depression, implementation of preventive actions is crucial. In France, two prenatal preventive measures are available to the general population: early prenatal interview (EPI) and antenatal classes (ANC). OBJECTIVE: To explore the independent associations between EPI and / or ANC and maternal depressive symptoms at 2 months postpartum. METHOD: We used data from the Etude Longitudinale Française depuis l'Enfance (ELFE), a French national representative cohort of children and their parents, followed-up from birth to early adulthood. Data concerning characteristics were collected from the mothers during the maternity stay and between 6/8 weeks' post-partum. The level of depressive symptoms was scored by the French version of the Edinburgh Postnatal Depression Scale (EPDS) between 6/8 weeks' post-partum. We considered EPDS score ≥10 indicative of postnatal psychological distress (PPD) and EPDS ≥12 for postnatal depressive symptoms (PNDS). After data imputation, multivariate logistic regression analysis was performed. RESULTS: Among the 16,411 mothers included in our sample, 26% benefited both from EPI and ANC, 31.1 % of ANC, 7.7% of an EPI and 35% of neither; 20,1% presented PPD and 12,1% PNDS. The likelihood of presenting PPD was significantly higher in mothers who had neither had EPI nor ANC (OR = 1.15 (95% CI : 1.01-1.30). There was no association between receiving or not an EPI and/or ANC and presenting PNDS. CONCLUSIONS: Antenatal preventive measures may be helpful to prevent PPD at 2 months' post- partum, while PNDS do not seem to be influenced by these actions.


Asunto(s)
Depresión Posparto , Depresión , Adulto , Niño , Estudios de Cohortes , Depresión Posparto/diagnóstico , Depresión Posparto/epidemiología , Depresión Posparto/prevención & control , Femenino , Humanos , Madres , Embarazo , Factores de Riesgo
6.
Eur Psychiatry ; 30(5): 562-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25843027

RESUMEN

BACKGROUND: There is debate as to whether maternal tobacco use in pregnancy is related to offspring behaviour later on. We tested this association examining multiple aspects of children's behaviour at age 5 and accounting for parental smoking outside of pregnancy, as well as child and family characteristics. METHODS: Data come from a prospective community based birth cohort study (EDEN; n=1113 families in France followed since pregnancy in 2003-2005 until the child's 5th birthday). Maternal tobacco use in pregnancy was self-reported. Children's socio-emotional development (emotional symptoms, conduct problems, symptoms of hyperactivity/inattention, peer relationship problems, prosocial behaviour) was assessed by mothers using the Strengths and Difficulties Questionnaire (SDQ) at age 5 years. Logistic regression analyses controlled for Inverse Probability Weights (IPW) of maternal tobacco use calculated based on study center, children's characteristics (sex, premature birth, low birth weight, breastfeeding), maternal characteristics (age at the child's birth, psychological difficulties and alcohol use in pregnancy, post-pregnancy depression, and smoking), paternal smoking in and post-pregnancy, parental educational attainment, family income, parental separation, and maternal negative life events. RESULTS: Maternal smoking in pregnancy only predicted children's high symptoms of hyperactivity/inattention (sex and study center-adjusted ORs: maternal smoking in the 1st trimester: 1.95, 95%CI: 1.13-3.38; maternal smoking throughout pregnancy: OR=2.11, 95%CI: 1.36-3.27). In IPW-controlled regression models, only children of mothers who smoked throughout pregnancy had significantly elevated levels of hyperactivity/inattention (OR=2.20, 95%CI: 1.21-4.00). CONCLUSIONS: Maternal tobacco smoking in pregnancy may contribute directly or through epigenetic mechanisms to children's symptoms of hyperactivity/inattention.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/etiología , Conducta Materna , Relaciones Madre-Hijo , Fumar/efectos adversos , Adulto , Niño , Preescolar , Estudios de Cohortes , Depresión/psicología , Femenino , Francia , Humanos , Recién Nacido , Masculino , Intercambio Materno-Fetal , Embarazo , Estudios Prospectivos , Factores de Riesgo
7.
Biomaterials ; 12(1): 25-31, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2009341

RESUMEN

The basic mechanisms underlying skin-implant interactions were investigated by means of in vitro experiments with fibroblast and epithelial cell cultures. Cells were cultured on various implant materials treated with radio frequency glow discharge. The possible influence of this treatment on the morphological mode of cell attachment, as well as cell behaviour in attachment and growth rate were investigated. The results demonstrate that there are significant behavioural differences between fibroblasts and epithelial cells.


Asunto(s)
Materiales Biocompatibles , Fibroblastos/ultraestructura , Prótesis e Implantes , Piel/ultraestructura , Cicatrización de Heridas , Animales , Adhesión Celular , Movimiento Celular , Células Cultivadas , Desmosomas/ultraestructura , Epitelio/fisiología , Epitelio/ultraestructura , Fibroblastos/fisiología , Microscopía Electrónica , Ratas , Fenómenos Fisiológicos de la Piel
8.
Biomaterials ; 10(9): 604-8, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2611309

RESUMEN

The objective of this study was to enlarge the understanding of the basic mechanisms underlying epithelial tissue implant reaction by means of in vitro experiments with epithelial cell cultures. For the experiments, rat palatal epithelial cells were cultured on various implant materials. The implant surfaces were treated by different procedures. The possible influence of these treatments on the attachment percentage and growth rate of the cells was studied. The results of the experiments demonstrate no significant relation between surface treatment and the behaviour of rat palatal epithelial cells cultured on the various kinds of substrates relevant for implants.


Asunto(s)
Células Epiteliales , Paladar Blando/citología , Animales , Adhesión Celular , Células Cultivadas , Medios de Cultivo , Epitelio/crecimiento & desarrollo , Ratas , Ratas Endogámicas , Propiedades de Superficie
9.
Biomaterials ; 13(13): 959-68, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1477267

RESUMEN

Recently, it has been demonstrated that the soft tissue response to polymeric filter implants was predominantly dependent on the implant surface topography and that variation in the implant material had little effect. The purpose of this study, therefore, was to compare histologically the soft tissue response to sintered fibre-web implants made from different materials and with varying web porosity. Three different fibre-web materials with two different weights and two different porosities were used. The implants were inserted subcutaneously in the dorsum of rabbits. The implants were left in situ for 4 and 12 wk. Histological and tissue compatibility evaluations were performed. It is found that all the tested fibre-web materials show a good biocompatible behaviour. In addition, the results appear to indicate a relation between flexibility of an implant material and tissue behaviour.


Asunto(s)
Materiales Biocompatibles , Prótesis e Implantes , Tejido Adiposo/patología , Animales , Fibroblastos/patología , Conejos , Acero Inoxidable , Titanio
10.
Biomaterials ; 18(6): 483-8, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9111952

RESUMEN

The stability of radiofrequency (RF) magnetron sputtered calcium phosphate was studied under cyclically loaded conditions. The coatings were deposited on titanium bars and tested in either dry or wet conditions X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy were used to characterize the as-sputtered and tested coatings. XRD demonstrated that the amorphous structure after annealing at 650 C changed into a crystalline apatite structure. The residual stresses were determined by the XRD cos 2 i/i method. These residual film stresses were influenced by the coating conditions and the crystalline sputtered coating showed the presence of compressive stresses. SEM demonstrated that, after cyclic loading conditions in air, the crystalline sputter-coated Ti-6A1-4V bars showed a partial coating loss. Furthermore, in wet conditions (simulated body fluid) only the heat-treated sputter-coated bars appeared to be stable. On the other hand, the amorphous coating only showed signs of delamination in the more highly stressed regions, while in the less stressed regions a Ca-P precipitate was formed. On the basis of these results we conclude that calcium phosphate coatings subjected to cyclic loading conditions show an important difference in fatigue behaviour when tested in either dry or wet conditions.


Asunto(s)
Materiales Biocompatibles/química , Fosfatos de Calcio/química , Ondas de Radio , Absorciometría de Fotón , Magnetismo , Ensayo de Materiales/métodos , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Difracción de Rayos X
11.
Biomaterials ; 17(12): 1251-6, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8799510

RESUMEN

Dacron velour is often used to anchor a percutaneous device, like the catheter used in peritoneal dialysis. However, exit-site infections complicate this method of dialysis and are supposed to be related to the design of the catheter. In animal experiments, a percutaneous device provided with a titanium fibre mesh to anchor the implant was not affected by infectious complications. The purpose of this study was to compare the differences in soft tissue reaction to Dacron velour and titanium fibre mesh under the same experimental conditions. Therefore, we placed implants, provided with either Dacron or titanium mesh, subcutaneously in the dorsum of goats. The implants were left in situ for 4 months. Histological and histomorphological evaluations were performed. It was found that the soft tissue response inside the Dacron was mainly inflammatory, while the titanium mesh evoked good biocompatible behaviour. We concluded that the limited fibrous tissue ingrowth into the Dacron cuff has to be the reason for the observed high failure incidence of a percutaneous device.


Asunto(s)
Poliésteres , Prótesis e Implantes , Titanio , Administración Cutánea , Animales , Materiales Biocompatibles , Cateterismo , Femenino , Cabras , Microscopía , Diálisis Peritoneal , Siliconas
12.
Biomaterials ; 18(2): 161-6, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9022964

RESUMEN

In previous experiments a new type of percutaneous device for implantation in soft tissue was designed, containing a sintered titanium fibre mesh. The devices are inserted by a so-called "two-phase' surgical technique with an intervening healing period of 3 months between insertion of the subcutaneous and percutaneous parts. From a clinical point of view, this time interval is too long. The aim of this study was to investigate whether it was possible to reduce the intervening healing period. The implants were inserted in the backs of nine goats. In each goat, six implants were placed with intervals of 1 week. Consequently, at the end of the experiment, in each goat six implants were present with implantation periods ranging from 1 to 6 weeks. After 6 weeks, the animals were killed and the implants with surrounding tissue were processed histologically. Analysis demonstrated that during the first 2 weeks an inflammatory response was present. Thereafter, no difference in tissue response was found between the various implantation periods. In conclusion, the experiment suggests that for titanium mesh percutaneous devices a 3-week healing period is sufficient between the installation of the subcutaneous and percutaneous parts.


Asunto(s)
Materiales Biocompatibles , Prótesis e Implantes , Titanio , Cicatrización de Heridas , Heridas y Lesiones/terapia , Animales , Cápsulas , Femenino , Cabras , Factores de Tiempo , Heridas y Lesiones/patología , Heridas y Lesiones/fisiopatología
13.
Biomaterials ; 24(15): 2623-9, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12726716

RESUMEN

RF magnetron sputter deposition was used to produce 0.1, 1.0 and 4.0 microm thick Ca-P coatings on TiO(2)-blasted titanium discs. Half of the as-sputtered coated specimens were subjected to an additional infrared heat treatment for 30s at 425-475 degrees C. X-ray diffraction demonstrated that infrared radiation changed the amorphous 4 microm sputtered coatings into an amorphous-crystalline structure, while the amorphous 0.1 and 1 microm changed in a crystalline apatite structure with the presents of tetracalciumphosphate as a second phase. Scanning electron microscopically examination of the sputtered coatings revealed that annealing of the 4 microm thick coatings resulted in the appearance of small cracks. Subsequently, the discs were implanted subcutaneous into the back of rabbits. After 1, 4, 8 and 12 weeks of implantation, the implants were retrieved and prepared for histological and physicochemical evaluation. Histological evaluation revealed that the tissue response to all coated implants was very uniform. A very thin connective tissue capsule surrounded all implants. The capsule was usually free of inflammatory cells. At the interface, there was a close contact between the capsule and implant surface and no inflammatory cells were seen. Physicochemical evaluation showed that the 0.1 and 1 microm thick amorphous coatings had disappeared within 1 week of implantation. On the other hand, the 4 microm thick amorphous phase disappeared during the implantation periods, which was followed by the precipitation of a crystalline carbonate apatite. Further, at all implantation periods the heat-treated 1 and 4 microm thick coatings could be detected. Occasionally, a granular precipitate was deposited on the heat-treated 4 microm thick coating. Fourier transform infrared spectroscopy showed the formation of carbonate apatite (CO(3)-AP) on the 4 microm thick amorphous coating and on the heat-treated specimens. On basis of our findings, we conclude that 1 microm thick heat-treated Ca-P sputter coating on roughened titanium implants appear to be of sufficient thickness to show bioactive properties, under in vivo conditions.


Asunto(s)
Fosfatos de Calcio/química , Materiales Biocompatibles Revestidos/química , Prótesis e Implantes , Titanio/química , Animales , Femenino , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Conejos , Ondas de Radio , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Difracción de Rayos X
14.
Biomaterials ; 18(6): 495-501, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9111954

RESUMEN

The aim of the present study is to determine the possibility of measuring the bone mineral density (BMD) around implants by dual energy X-ray absorptiometry (DEXA). Therefore, the trabecular BMD was measured close to 127-600 microns and at a distance from various uncoated and Ca-P-coated implants inserted into the femoral condyle of goals. The implants were left in situ for 12 weeks. In addition, the bone-implant interface was evaluated histologically. For comparative reasons the BMD of non-implanted lateral and medial femoral condyles was also measured. The reproducibility of the measurements, expressed as a coefficient of variation, was found to be 0.44%. Moreover, the regions closest to the implants exhibited a higher BMD than all other regions, and the regions located in the medial condyle showed a higher BMD than the lateral condylar regions. Although the histological sections of the implants in the medial condyle demonstrated more bone contact with the coated than with the uncoated implants, a higher density was measured around the uncoated implants. The results regarding the non-implanted condyles indicated a higher density in the medial than in the lateral condyle. In view of these results, we conclude that BMD around dental implants depends on the location of the implant and that DEXA appears to be an excellent tool for analysing bone-implant reactions.


Asunto(s)
Densidad Ósea , Sustitutos de Huesos , Prótesis e Implantes , Absorciometría de Fotón/métodos , Aleaciones , Animales , Femenino , Fémur , Cabras , Hidroxiapatitas , Reproducibilidad de los Resultados , Factores de Tiempo , Titanio
15.
J Invest Surg ; 5(1): 35-44, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1315568

RESUMEN

It has been demonstrated that direct attachment to bony skeletal tissues favors the longevity of percutaneous devices (PDs). This study is focused on improvement of the success rates by using a two-stage implantation technique. For this purpose, cylindrical-shaped PDs were inserted into the tibia of rabbits. The enossal part of the implants was made of Ti6Al4V and was coated with a layer hydroxyapatite (HA). The percutaneous part was made of dense HA. In a first surgical session, the enossal part of the implants was inserted. In a second implantation session, about 3 months later, the percutaneous part was fixed into the enossal part. The implants were left in situ for 5 months after the second session. Clinical and histological investigations were performed. The results confirmed the previous finding--that bone anchoring is effective in the maintenance of a permanent percutaneous passage. On the other hand, it could not be proven that a two-stage implantation procedure improves the success rate of one-stage bone-anchored PDs.


Asunto(s)
Prótesis e Implantes , Tibia/cirugía , Cicatrización de Heridas/fisiología , Animales , Durapatita , Hidroxiapatitas , Conejos , Tibia/citología , Titanio , Resultado del Tratamiento
16.
J Invest Surg ; 2(1): 29-49, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2487397

RESUMEN

The major fact in determining percutaneous implant success is the formation of a stable skin-implant junction. However, the characteristics an implant material must meet to secure a durable percutaneous seal are still unknown. The objective of this study, therefore, is to gain more insight into the mechanisms underlying implant-skin reactions by means of in vitro cell culture and in vivo animal experiments. For the in vitro experiments rat palatal epithelial cells were cultured on various implant materials and the possible influence of the initial surface free energy and state of cleanliness of these materials on the growth rate of cells was studied. The results of these experiments demonstrate no significant relation between these parameters and cellular growth. In the in vivo experiments, plasma-sprayed and dense hydroxylapatite percutaneous implants were inserted into the tibia and dorsum of guinea pigs and into the tibia and onto the cranium of rabbits. The implants were left in situ for 3 weeks to 8 months. Clinical and histological investigations were performed. The results show, that stabilization of a percutaneous implant by bony skeletal tissue is effective in the maintenance of a permanent percutaneous passage.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos , Prótesis e Implantes , Animales , Adhesión Celular , División Celular , Células Cultivadas , Estudios de Evaluación como Asunto , Cobayas , Microscopía Electrónica , Conejos , Piel/patología , Propiedades de Superficie
17.
J Invest Surg ; 7(2): 123-34, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8049175

RESUMEN

An adequate histologic evaluation is a prerequisite for a good understanding of the behavior of tissue to implant materials. However, despite improvements in histologic sectioning techniques, few studies have used histomorphometric methods for the quantification of the tissue response. This paper discusses new simple histologic grading scales, which can be used for the fast standardized light microscopic analysis of the biocompatibility of hard and soft tissue implants. Two examples of the application of the grading scales are demonstrated.


Asunto(s)
Ensayo de Materiales , Prótesis e Implantes , Animales , Huesos/patología , Estudios de Evaluación como Asunto , Técnicas Histológicas , Conejos , Estándares de Referencia
18.
J Biomed Mater Res B Appl Biomater ; 66(1): 447-56, 2003 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-12808607

RESUMEN

This in vivo study evaluated the fixation of two types of titanium implants with the use of an injectable calcium-phosphate (CaP) cement. The cement was either used to create a cement mantle (Type A implant) or as an additive to press-fit placed titanium plasma sprayed implants (Type B implant). The implants were placed in trabecular bone of the medial femoral condyle of goats and left in place for 2 and 10 weeks. Mechanical evaluation of the implant fixation was done by torque testing. This showed that for the Type A implants the calcium-phosphate cement's performance was significantly inferior (P < 0.05) to that of polymethylmethacrylate cement fixation. For the two-week Type B implants a significant increase (P < 0.05) in failure load was found for calcium-phosphate cemented implants compared with just press-fitted Type B implants. Histological evaluation revealed that for Type A implants, failure during torque testing occurred at the implant-cement interface. In contrast, for Type B implants, failure occurred in the bone-implant interface for press-fit-placed devices and in the cement layer for CaP-cemented devices. Further, the CaP cement was found to be overgrown with new formed bone already after 2 weeks of implantation. The cement showed resorption due to regular bone remodeling. On the basis of these observations, it was concluded that the use of injectable CaP cement might facilitate earlier loading of press-fit inserted titanium implants. Nevertheless, the results have to be confirmed in dynamical mechanical as well as loaded in vivo studies.


Asunto(s)
Cementos para Huesos , Fosfatos de Calcio , Prótesis e Implantes , Titanio , Animales , Fenómenos Biomecánicos , Fosfatos de Calcio/administración & dosificación , Femenino , Cabras , Inyecciones , Ensayo de Materiales , Oseointegración , Polimetil Metacrilato , Factores de Tiempo
19.
ASAIO J ; 42(6): 961-7, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8959270

RESUMEN

A percutaneous device, provided with a sintered titanium fiber web structure, was designed for implantation in soft tissue. The percutaneous device was inserted by a two stage surgical technique. Between the insertion of the subcutaneous and percutaneous part was an intervening healing period of 3 months. However, most clinicians prefer a one stage implant. Therefore, the authors wanted to investigate the soft tissue response to one stage and two stage percutaneous devices. The implants were inserted in the flanks of 12 goat. In each goat, one one stage and one two stage implant were placed and inspected on a regular base. It appeared that, during the experiments, significantly more one stage devices were extruded. Four months after the second surgical session, all successful implants with their surrounding tissues were retrieved for light microscopic and histomorphometric analysis. No difference in epidermal downgrowth and sulcus width was demonstrated between the implants. Furthermore, the fiber mesh was surrounded by a thin fibrous capsule free from inflammatory cells. Inside the fiber mesh structure, connective tissue was present with only scattered foci of inflammatory cells. An enhanced inflammatory tissue response was found inside the titanium mesh of one stage compared to two stage implants. This study showed that the two stage surgical procedure for implantation of a percutaneous device worked better than the one-stage surgical technique.


Asunto(s)
Diálisis Peritoneal , Prótesis e Implantes/efectos adversos , Titanio/metabolismo , Animales , Femenino , Fibroblastos/citología , Fibroblastos/patología , Cabras , Complicaciones Intraoperatorias/prevención & control , Polietilenos/metabolismo , Porosidad , Complicaciones Posoperatorias/prevención & control , Prótesis e Implantes/normas , Piel/citología , Piel/lesiones , Piel/patología , Traumatismos de los Tejidos Blandos , Cicatrización de Heridas/fisiología
20.
Vet Rec ; 145(12): 329-33, 1999 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-10530881

RESUMEN

Ninety transponders (microchips), 45 made of bioglass, 30 made of acid-etched bioglass, and 15 made of bioglass and provided with a polypropylene cap, were inserted into 15 dogs in six different locations: on the left and right side of the head, and on the left and right shoulders, both cranial and caudal to the dorsum. The transponders were left in place for 16 weeks, during which their position was determined by means of an electronic reader and radiographs, and they were then retrieved and examined histologically. A clinical evaluation revealed that about half of the transponders inserted in all the shoulder locations had migrated to some extent, whereas the transponders in the head location had hardly moved. There were no differences in the extent of migration between the different types of transponders. Histological analysis showed that almost all the transponders were surrounded by a thin fibrous capsule with no sign of any gross inflammatory reaction.


Asunto(s)
Sistemas de Identificación Animal , Materiales Biocompatibles , Cerámica , Migración de Cuerpo Extraño/veterinaria , Implantes Experimentales , Animales , Perros , Diseño de Equipo , Femenino , Migración de Cuerpo Extraño/diagnóstico por imagen , Masculino , Polipropilenos , Radiografía
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