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BACKGROUND: Going-to-sleep in the supine position in later pregnancy (≥28 weeks) has been identified as a risk factor for stillbirth. Internationally, public awareness campaigns have been undertaken encouraging women to sleep on their side during late pregnancy. AIM: This study aimed to identify sleep practices, attitudes and knowledge in pregnant women, to inform an Australian safe sleeping campaign. METHODS: A web-based survey of pregnant women ≥28 weeks' gestation conducted from November 2017 to January 2018. The survey was adapted from international sleep surveys and disseminated via pregnancy websites and social media platforms. FINDINGS: Three hundred and fifty-two women participated. Five (1.6%) reported going to sleep in the supine position. Most (87.8%) had received information on the importance of side-sleeping in pregnancy. Information was received from a variety of sources including maternity care providers (186; 66.2%) and the internet (177; 63.0%). Women were more likely to report going to sleep on their side if they had received advice to do so (OR 2.3; 95% CI 1.0-5.1). Thirteen (10.8%) reported receiving unsafe advice, including changing their going-to-sleep position to the supine position. DISCUSSION: This indicates high level awareness and practice of safe late-pregnancy going-to-sleep position in participants. Opportunities remain for improvement in the information provided, and understanding needs of specific groups including Aboriginal and Torres Strait Islander women. CONCLUSION: Findings suggest Australian women understand the importance of sleeping position in late pregnancy. Inconsistencies in information provided remain and may be addressed through public awareness campaigns targeting women and their care providers.
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Servicios de Salud Materna , Australia , Femenino , Humanos , Embarazo , Sueño , Mortinato , Posición SupinaRESUMEN
OBJECTIVE: To investigate behavioural and social characteristics of women who experienced a late stillbirth compared with women with ongoing live pregnancies at similar gestation. DESIGN: Case-control study. SETTING: 41 maternity units in the UK. POPULATION: Women who had a stillbirth ≥28 weeks' gestation (n = 287) and women with an ongoing pregnancy at the time of interview (n = 714). METHODS: Data were collected using an interviewer-administered questionnaire which included questions regarding women's behaviours (e.g. alcohol intake and household smoke exposure) and social characteristics (e.g. ethnicity, employment, housing). Stress was measured by the 10-item Perceived Stress Scale. MAIN OUTCOME MEASURE: Late stillbirth. RESULTS: Multivariable analysis adjusting for co-existing social and behavioural factors showed women living in the most deprived quintile had an increased risk of stillbirth compared with the least deprived quintile (adjusted odds ratio [aOR] 3.16; 95% CI 1.47-6.77). There was an increased risk of late stillbirth associated with unemployment (aOR 2.32; 95% CI 1.00-5.38) and women who declined to answer the question about domestic abuse (aOR 4.12; 95% CI 2.49-6.81). A greater number of antenatal visits than recommended was associated with a reduction in stillbirth (aOR 0.26; 95% CI 0.16-0.42). CONCLUSIONS: This study demonstrates associations between late stillbirth and socio-economic deprivation, perceived stress and domestic abuse, highlighting the need for strategies to prevent stillbirth to extend beyond maternity care. Enhanced antenatal care may be able to mitigate some of the increased risk of stillbirth. TWEETABLE ABSTRACT: Deprivation, unemployment, social stress & declining to answer about domestic abuse increase risk of #stillbirth after 28 weeks' gestation.
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Mortinato/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Violencia Doméstica , Inglaterra/epidemiología , Femenino , Edad Gestacional , Humanos , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Embarazo , Factores de Riesgo , Factores Socioeconómicos , Mortinato/economía , Mortinato/psicología , Estrés Psicológico/complicaciones , Adulto JovenRESUMEN
OBJECTIVE: To report maternal sleep practices in women who experienced a stillbirth compared with controls with ongoing live pregnancies at similar gestation. DESIGN: Prospective case-control study. SETTING: Forty-one maternity units in the United Kingdom. POPULATION: Women who had a stillbirth after ≥ 28 weeks' gestation (n = 291) and women with an ongoing pregnancy at the time of interview (n = 733). METHODS: Data were collected using an interviewer-administered questionnaire that included questions on maternal sleep practices before pregnancy, in the four weeks prior to, and on the night before the interview/stillbirth. MAIN OUTCOME MEASURES: Maternal sleep practices during pregnancy. RESULTS: In multivariable analysis, supine going-to-sleep position the night before stillbirth had a 2.3-fold increased risk of late stillbirth [adjusted Odds Ratio (aOR) 2.31, 95% CI 1.04-5.11] compared with the left side. In addition, women who had a stillbirth were more likely to report sleep duration less than 5.5 hours on the night before stillbirth (aOR 1.83, 95% CI 1.24-2.68), getting up to the toilet once or less (aOR 2.81, 95% CI 1.85-4.26), and a daytime nap every day (aOR 2.22, 95% CI 1.26-3.94). No interaction was detected between supine going-to-sleep position and a small-for-gestational-age infant, maternal body mass index, or gestational age. The population-attributable risk for supine going-to-sleep position was 3.7% (95% CI 0.5-9.2). CONCLUSIONS: This study confirms that supine going-to-sleep position is associated with late stillbirth. Further work is required to determine whether intervention(s) can decrease the frequency of supine going-to-sleep position and the incidence of late stillbirth. TWEETABLE ABSTRACT: Supine going-to-sleep position is associated with 2.3× increased risk of stillbirth after 28 weeks' gestation. PLAIN LANGUAGE SUMMARY: Stillbirth, the death of a baby before birth, is a tragedy for mothers and families. One approach to reduce stillbirths is to identify factors that are associated with stillbirth. There are few risk factors for stillbirth that can be easily changed, but this study is looking at identifying how mothers may be able to reduce their risk. In this study, we interviewed 291 women who had a stillbirth and 733 women who had a live-born baby from 41 maternity units throughout the UK. The mothers who had a stillbirth were interviewed as soon as practical after their baby died. Mothers who had a live birth were interviewed during their pregnancies at the same times in pregnancy as when the stillbirths occurred. We did not interview mothers who had twins or who had a baby with a major abnormality. Mothers who went to sleep on their back had at least twice the risk of stillbirth compared with mothers who went to sleep on their left-hand side. This study suggests that 3.7% of stillbirths after 28 weeks of pregnancy were linked with going to sleep lying on the back. This study also shows that the link between going-to-sleep position and late stillbirth was not affected by the duration of pregnancy after 28 weeks, the size of the baby, or the mother's weight. Women who got up to the toilet once or more at night had a reduced risk of stillbirth. This is the largest of four similar studies that have all shown the same link between the position in which a mother goes to sleep and stillbirth after 28 weeks of pregnancy. Further studies are needed to see whether women can easily change their sleep position in late pregnancy and whether changing the position a mother goes to sleep in reduces stillbirth.
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Sueño/fisiología , Mortinato/epidemiología , Adulto , Estudios de Casos y Controles , Femenino , Edad Gestacional , Unidades Hospitalarias , Humanos , Entrevistas como Asunto , Servicios de Salud Materna , Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Factores de Riesgo , Medicina Estatal , Posición Supina/fisiología , Reino Unido/epidemiologíaRESUMEN
OBJECTIVE: Patient portals are online applications that allow patients to interact with healthcare organizations. Portal adoption is increasing, and secure messaging between patients and healthcare providers is an emerging form of outpatient interaction. Research about portals and messaging has focused on medical specialties. We characterized adoption of secure messaging and the contribution of messaging to outpatient interactions across diverse clinical specialties after broad portal deployment. METHODS: This retrospective cohort study at Vanderbilt University Medical Center examined use of patient-initiated secure messages and clinic visits in the three years following full deployment of a patient portal across adult and pediatric specialties. We measured the proportion of outpatient interactions (i.e., messages plus clinic visits) conducted through secure messaging by specialty over time. Generalized estimating equations measured the likelihood of message-based versus clinic outpatient interaction across clinical specialties. RESULTS: Over the study period, 2,422,114 clinic visits occurred, and 82,159 unique portal users initiated 948,428 messages to 1,924 recipients. Medicine participated in the most message exchanges (742,454 messages; 78.3% of all messages sent), followed by surgery (84,001; 8.9%) and obstetrics/gynecology (53,424; 5.6%). The proportion of outpatient interaction through messaging increased from 12.9% in 2008 to 33.0% in 2009 and 39.8% in 2010 (p<0.001). Medicine had the highest proportion of outpatient interaction conducted through messaging in 2008 (23.3% of outpatient interactions in medicine). By 2010, this proportion was highest for obstetrics/gynecology (83.4%), dermatology (71.6%), and medicine (56.7%). Growth in likelihood of message-based interaction was greater for anesthesiology, dermatology, obstetrics/gynecology, pediatrics, and psychiatry than for medicine (p<0.001). CONCLUSIONS: This study demonstrates rapid adoption of secure messaging across diverse clinical specialties, with messaging interactions exceeding face-to-face clinic visits for some specialties. As patient portal and secure messaging adoption increase beyond medicine and primary care, research is needed to understand the implications for provider workload and patient care.
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Seguridad Computacional , Atención a la Salud/tendencias , Correo Electrónico/tendencias , Medicina/estadística & datos numéricos , Pacientes Ambulatorios , Adulto , Niño , Estudios de Cohortes , Registros Electrónicos de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Prior cross-sectional studies have demonstrated an association between hypercalciuria and low bone mineral density (BMD) in children and adults. However, the natural history of BMD in children with hypercalciuria and its response to therapy has not been evaluated. The objective of this retrospective study was to determine the change over time in lumbar (L1 - L4) BMD Z-score measured on sequential DXA scans in 19 children with hypercalciuria treated with dietary recommendations without (n = 12, Group A) and with citrate (n = 7, Group B). The mean lumbar bone density Z-score/year decreased in Group A (-0.11 ±/0.41) indicating that children with hypercalciuria lose L1 - L4 BMD over time. In contrast, the L1 - L4 BMD Zscore/ year increased in Group B (0.19 ± 0.38) suggesting that pharmacologic therapy may reverse this trend. Similarly 75% of patients in Group A, but only 29% patients in Group B had a decrease in L1 - L4 BMD. There was a definite, although not significant, trend towards improved mean bone mineral density Z-score per year and a lower percentage of patients with a decreased Z-score in hypercalciuric children treated with potassium citrate. Our findings suggest the possibility that dietary recommendations alone is not adequate as the bone mineral density of children with hypercalciuria will decrease over time, potentially increasing the risk for osteoporosis as an adult.
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Densidad Ósea , Conducta Alimentaria , Hipercalciuria/dietoterapia , Vértebras Lumbares/diagnóstico por imagen , Absorciometría de Fotón , Adolescente , Niño , Femenino , Humanos , Masculino , Citrato de Potasio/uso terapéutico , Estudios Retrospectivos , UrinálisisRESUMEN
STATEMENT OF PROBLEM: Although an interaction of malocclusion, parafunction, and temporomandibular joint disorders (TMD) can be inferred from the experience of daily practice, scientific evidence to corroborate this hypothesis does not exist. However, there are indications that TMD and headaches may be intertwined. PURPOSE: The purpose of this study was to identify the presence or absence of an association of occlusal interferences, parafunction, TMD, or physiologic, muscular, or prosthodontic factors with the occurrence of headache. MATERIAL AND METHODS: In a private practice population of 1031 subjects (436 men and 595 women, mean age 49.6 years) the demographic parameters, headache and general pain history, habits and general personal information were recorded. Clinical examination for dental, muscular, and temporomandibular joint pathology was accomplished. Data were statistically analyzed using the Mann-Whitney U, Kruskal-Wallis, and Chi-Square tests (α = .05). A multinomial logistic regression analysis was performed with respect to confounding variables. RESULTS: Headache affliction was found to affect women more frequently than men (1.7:1). Students and non academics were more prone to suffer from headache. Parafunction (P=.001), TMD (P=.001) and gross differences between centric occlusion and maximum intercuspation of more than a 3 mm visible track marked with 8 µm articulation foil (P=.001) significantly influenced the presence of headache. Headache intensity and frequency decreased with age. While tension-type headache was most frequently diagnosed, the parameters studied were not significantly associated with one certain headache diagnosis more frequently than others. CONCLUSIONS: Stomatognathic factors of TMD, parafunction, and gross differences between centric occlusion and maximum intercuspation of more than 3 mm are associated with headache. These findings should be interpreted with caution due to the cross-sectional nature of this study.
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Bruxismo/complicaciones , Oclusión Dental Traumática/complicaciones , Cefalea/etiología , Trastornos de la Articulación Temporomandibular/complicaciones , Atrición Dental/complicaciones , Adolescente , Adulto , Factores de Edad , Distribución de Chi-Cuadrado , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores Sexuales , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Adulto JovenRESUMEN
The purpose of this study was to evaluate the retention and marginal seating discrepancy of complete veneer crown cemented with zinc phosphate cement using various preparation convergence designs. The method employed was that of cementing cast metal crowns onto 46 metal dies fabricated as complete veneer crown preparations with various convergence angles ranging from 0 degrees to 70 degrees and a shoulder finish line. The marginal discrepancy was calculated by measuring the change in crown height before and after cementation using an optical measuring microscope. The force required to remove the crowns from the dies in a vertical direction was determined using an Instron universal testing machine and recorded as retention. The increase in preparation convergence exhibited a wide variation of seating discrepancy between specimens, ranging from 4.58 +/- 1.13 to 73.13 +/- 78.32 microm. Significant tilting of crown was observed as the convergence angle of preparation increased. The retention values ranged from 4.03 +/- 0.61 to 12.12 +/- 0.33 MPa. The Pearson analysis revealed statistically significant correlations between preparation convergence and marginal discrepancy (r = +0.62), and retention (r = -0.91). Crown retention and marginal discrepancy were influenced by the preparation convergence design.
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Coronas , Retención de Prótesis Dentales , Coronas con Frente Estético , Preparación Protodóncica del Diente/métodos , Cementación/métodos , Fracaso de la Restauración Dental , Humanos , Ensayo de Materiales/métodos , Cemento de Fosfato de ZincRESUMEN
The purpose of this study was to evaluate the retention and marginal seating discrepancy of complete veneer crown cemented with zinc phosphate using various preparation convergence designs. The method employed was that of cementing cast metal crowns onto 46 metal dies fabricated as complete veneer crown preparations with various convergence angles ranging from 0 degrees to 70 degrees and a shoulder finish line. The marginal discrepancy was calculated by measuring the change in crown height before and after cementation using an optical measuring microscope. The force required to remove the crowns from the dies in a vertical direction was determined using an Instron universal testing machine and recorded as retention. The increase in preparation convergence exhibited a wide variation of seating discrepancy between specimens, ranging from 4.58 +/- 1.13 to 73.13 +/- 78.32 microm. Significant tilting of crown was observed as the convergence angle of preparation increased. The retention values ranged from 4.03 +/- 0.61 to 12.12 +/- 0.33 MPa. The Pearson analysis revealed statistically significant correlations between preparation convergence and marginal discrepancy (r = +0.62), and retention (r = -0.91). Complete veneer crown retention and marginal discrepancy were influenced by the preparation convergence design.
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Retención de Prótesis Dentales , Coronas con Frente Estético , Preparación Protodóncica del Diente , Cementación , Humanos , Cemento de Fosfato de ZincAsunto(s)
Prótesis Dental , Restauración Dental Permanente , Caries Dental/prevención & control , Implantes Dentales , Materiales Dentales , Oclusión Dental , Enfermedades de la Pulpa Dental/etiología , Humanos , Enfermedades Periodontales/tratamiento farmacológico , Enfermedades Periodontales/etiología , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/etiología , Trastornos de la Articulación Temporomandibular/terapiaRESUMEN
BACKGROUND: Renal toxicity is a major side-effect of aminoglycoside antibiotics and is characterized by an early impairment in proximal tubular function. In a previous study, we have shown that gentamicin administration to the rat causes an early impairment in sodium gradient-dependent phosphate (Na/Pi) cotransport activity. The purpose of our current study was to determine the molecular mechanisms of the impairment in Na/Pi cotransport activity, specifically the role of the proximal tubular type II Na/Pi cotransporter. METHODS: Rats were treated for one, two, and three days with two daily injections of 30 mg/kg body weight gentamicin or the vehicle. RESULTS: Gentamicin caused a progressive decrease in superficial cortical apical brush-border membrane (SC-BBM) Na/Pi cotransporter activity (856 +/- 93 in control vs. 545 +/- 87 pmol/mg BBM protein in 3-day gentamicin, P < 0.01). Western blot analysis showed a parallel and progressive decrease in SC-BBM Na/Pi cotransporter protein abundance, a 50% decrease after one day of treatment, a 63% decrease after two days of treatment, and an 83% decrease after three days treatment with gentamicin. In contrast, gentamicin treatment had no effect on Na/Pi cotransport activity or Na/Pi cotransporter protein abundance in BBM isolated from the juxtamedullary cortex (JMC-BBM). Immunofluorescence microscopy showed a major decrease in the expression of Na/Pi cotransporter protein in the apical membrane of the proximal convoluted tubule, with progressive intracellular accumulation of Na/Pi protein. Colocalization studies showed that in gentamicin-treated rats, Na/Pi protein was colocalized in the early endosomes and especially in the lysosomes. Northern blot analysis of cortical RNA interestingly showed no reduction in Na/Pi cotransporter mRNA abundance even after three days of gentamicin treatment. CONCLUSION: We conclude that gentamicin inhibits Na/Pi cotransport activity by causing a decrease in the expression of the type II Na/Pi cotransport protein at the level of the proximal tubular apical BBM and that inhibition of Na/Pi cotransport activity is most likely mediated by post-transcriptional mechanisms.
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Antibacterianos/farmacología , Proteínas Portadoras/metabolismo , Endocitosis , Gentamicinas/farmacología , Corteza Renal/metabolismo , Simportadores , Animales , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/genética , Endosomas/metabolismo , Técnicas In Vitro , Corteza Renal/efectos de los fármacos , Médula Renal/metabolismo , Lisosomas/metabolismo , Masculino , Microvellosidades/efectos de los fármacos , Microvellosidades/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Proteínas Cotransportadoras de Sodio-Fosfato , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo IIRESUMEN
Single-tooth implants are an increasingly popular method for replacing single teeth. While the effects of growth on implants in children have been well documented, the changes that occur in adults have not been studied with respect to single-tooth implants. It has been assumed that adults are stable and do not change; however, research in the last few years has indicated that adults do change with aging, and adult growth does occur. The changes in adults occur over decades rather than rapidly, as seen in children. Aging changes are readily apparent in the soft tissues of the face and create dramatic changes. Changes in the jaws and teeth occur as a result of continued, slow growth, in contrast to the aging effects seen in soft tissues. Growth changes occur in the arches and result in adaptive changes in the teeth over time, both vertically and horizontally, and in alignment. These dental changes may result in a lack of occlusion vertically or malposition of adjacent natural teeth relative to the implant crown. Clinicians may be well advised to observe and report these changes and warn patients that changes can occur over the service life of the implant-supported crown. These changes may require maintenance adjustments or possible remaking of the implant crown as a result of adult growth, wear, or the esthetic changes of aging.
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Envejecimiento/fisiología , Implantes Dentales de Diente Único , Desarrollo Maxilofacial/fisiología , Adulto , Niño , Arco Dental/crecimiento & desarrollo , Alisadura de la Restauración Dental , Estética Dental , Cara/fisiología , Humanos , Maloclusión/fisiopatología , Factores de Tiempo , Diente/fisiologíaRESUMEN
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.
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Dentadura Completa Superior , Hueso Paladar/anatomía & histología , Medición de la Producción del Habla , Habla/fisiología , Humanos , Fonética , Pruebas de Articulación del Habla , Lengua/fisiologíaRESUMEN
The dynamic relationship of dental and craniofacial development to the use of dental implants in a growing patient must be understood before this treatment is initiated. This article describes the three dimensions of maxillary, mandibular, and skeletal growth and their relationship to the placement of dental implants. Recommendations are made for the use of dental implants in the growing individual predicated on the above parameters of growth and development.
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Implantación Dental Endoósea , Implantes Dentales , Desarrollo Maxilofacial , Planificación de Atención al Paciente , Desarrollo Óseo , Niño , Arco Dental/crecimiento & desarrollo , Arco Dental/cirugía , Crecimiento , Humanos , Mandíbula/crecimiento & desarrollo , Mandíbula/cirugía , Maxilar/crecimiento & desarrollo , Maxilar/cirugía , Odontogénesis , Maduración Sexual , Cráneo/crecimiento & desarrolloRESUMEN
The practice of fixed prosthodontics has continually evolved as a result of progress in laboratory and biomaterials science, clinical technologies and adjunctive multidisciplinary treatment advancements. This brief review describes those enhancements and how they affect the state-of-the-art practice of fixed prosthodontics.
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Dentadura Parcial Fija , Pilares Dentales , Implantes Dentales , Materiales Dentales , Diseño de Dentadura , Dentadura Parcial Provisoria , Gingivoplastia , Humanos , Ortodoncia CorrectivaRESUMEN
Ectodermal dysplasia is commonly a difficult condition to manage with prosthodontics because of the typical oral deficiencies and because the afflicted individuals are quite young when they are evaluated for treatment. It is important that these individuals receive dental treatment at an early age for physiologic and psychosocial reasons. This article reviews the literature that pertains to the prosthodontic treatment of the disorder and the review includes considerations in behavior management and timing of treatment.
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Anodoncia/rehabilitación , Atención Dental para Enfermos Crónicos/métodos , Diseño de Dentadura , Displasia Ectodérmica/complicaciones , Anodoncia/etiología , Preescolar , Dentadura Completa , Dentadura Parcial Removible , Displasia Ectodérmica/rehabilitación , HumanosRESUMEN
Diagnosis of subtle Lisfranc injuries can be difficult for the examining clinician. Radiographs do not always reveal the full extent of tarsometatarsal injuries. We describe a clinical sign found in significant Lisfranc injuries that consists of a mid-foot ecchymotic area on the plantar aspect. This implies the potential for significant injury to the plantar tarsometatarsal ligaments. We call this the plantar ecchymosis sign. Patients with this injury and sign should be aggressively evaluated, with early consideration for stress radiographs and ORIF if indicated, as the prognosis of the undertreated Lisfranc injury is poor.
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Equimosis/diagnóstico , Traumatismos de los Pies/diagnóstico , Fracturas Óseas/cirugía , Huesos Metatarsianos/lesiones , Articulaciones Tarsianas/lesiones , Adulto , Diagnóstico Diferencial , Equimosis/complicaciones , Dermatosis del Pie/complicaciones , Dermatosis del Pie/diagnóstico , Traumatismos de los Pies/complicaciones , Traumatismos de los Pies/diagnóstico por imagen , Fijación Interna de Fracturas , Curación de Fractura/fisiología , Fracturas Óseas/diagnóstico por imagen , Humanos , Masculino , Huesos Metatarsianos/diagnóstico por imagen , Radiografía , Rango del Movimiento Articular , Articulaciones Tarsianas/diagnóstico por imagenRESUMEN
Glucocorticoids are important regulators of renal phosphate transport. This study investigates the role of alterations in renal brush border membrane (BBM) sodium gradient-dependent phosphate transport (Na-Pi cotransporter) mRNA and protein abundance in the dexamethasone induced inhibition of Na-Pi cotransport in the rat. Dexamethasone administration for 4 d caused a 1.5-fold increase in the Vmax of Na-Pi cotransport (1785 +/- 119 vs. 2759 +/- 375 pmol/5 s per mg BBM protein in control, P < 0.01), which was paralleled by a 2.5-fold decrease in the abundance of Na-Pi mRNA and Na-Pi protein. There was also a 1.7-fold increase in BBM glucosylceramide content (528 +/- 63 vs. 312 +/- 41 ng/mg BBM protein in control, P < 0.02). To determine whether the alteration in glucosylceramide content per se played a functional role in the decrease in Na-Pi cotransport, control rats were treated with the glucosylceramide synthase inhibitor, D-threo-1-phenyl-2-decanoyl-amino-3-morpholino-1-propanol (PDMP). The resultant 1.5-fold decrease in BBM glucosylceramide content (199 +/- 19 vs. 312 +/- 41 ng/mg BBM protein in control, P < 0.02) was associated with a 1.4-fold increase in Na-Pi cotransport activity (1422 +/- 73 vs. 1048 +/- 85 pmol/5 s per mg BBM protein in control, P < 0.01), and a 1.5-fold increase in BBM Na-Pi protein abundance. Thus, dexamethasone-induced inhibition of Na-Pi cotransport is associated with a decrease in BBM Na-Pi cotransporter abundance, and an increase in glucosylceramide. Since primary alteration in BBM glucosylceramide content per se directly and selectively modulates BBM Na-Pi cotransport activity and Na-Pi protein abundance, we propose that the increase in BBM glucosylceramide content plays an important role in mediating the inhibitory effect of dexamethasone on Na-Pi cotransport activity.
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Proteínas Portadoras/genética , Dexametasona/farmacología , Glicoesfingolípidos/análisis , Riñón/efectos de los fármacos , ARN Mensajero/análisis , Animales , Proteínas Portadoras/análisis , Riñón/química , Riñón/metabolismo , Masculino , Fluidez de la Membrana/efectos de los fármacos , Microvellosidades/efectos de los fármacos , Microvellosidades/metabolismo , Proteínas de Unión a Fosfato , Fosfatos/metabolismo , Ratas , Ratas Sprague-Dawley , Sodio/metabolismoRESUMEN
The UCLA abutment was developed to create implant-retained restorations with ideal contours, excellent esthetics, and minimal vertical space requirements for restorative materials. A major drawback of this abutment is that casting inaccuracies in the lost-wax process are difficult to control. This article describes a method of refining cast implant-retained restorations by use of electrical discharge machining.