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1.
BMC Geriatr ; 24(1): 526, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886679

RESUMEN

INTRODUCTION: Accelerometer-derived physical activity (PA) from cardiac devices are available via remote monitoring platforms yet rarely reviewed in clinical practice. We aimed to investigate the association between PA and clinical measures of frailty and physical functioning. METHODS: The PATTErn study (A study of Physical Activity paTTerns and major health Events in older people with implantable cardiac devices) enrolled participants aged 60 + undergoing remote cardiac monitoring. Frailty was measured using the Fried criteria and gait speed (m/s), and physical functioning by NYHA class and SF-36 physical functioning score. Activity was reported as mean time active/day across 30-days prior to enrolment (30-day PA). Multivariable regression methods were utilised to estimate associations between PA and frailty/functioning (OR = odds ratio, ß = beta coefficient, CI = confidence intervals). RESULTS: Data were available for 140 participants (median age 73, 70.7% male). Median 30-day PA across the analysis cohort was 134.9 min/day (IQR 60.8-195.9). PA was not significantly associated with Fried frailty status on multivariate analysis, however was associated with gait speed (ß = 0.04, 95% CI 0.01-0.07, p = 0.01) and measures of physical functioning (NYHA class: OR 0.73, 95% CI 0.57-0.92, p = 0.01, SF-36 physical functioning: ß = 4.60, 95% CI 1.38-7.83, p = 0.005). CONCLUSIONS: PA from cardiac devices was associated with physical functioning and gait speed. This highlights the importance of reviewing remote monitoring PA data to identify patients who could benefit from existing interventions. Further research should investigate how to embed this into clinical pathways.


Asunto(s)
Acelerometría , Desfibriladores Implantables , Ejercicio Físico , Tecnología de Sensores Remotos , Humanos , Masculino , Anciano , Anciano de 80 o más Años , Ejercicio Físico/fisiología , Fragilidad , Anciano Frágil , Marcapaso Artificial , Acelerometría/instrumentación , Acelerometría/métodos , Velocidad al Caminar , Rendimiento Físico Funcional , Tecnología de Sensores Remotos/instrumentación , Tecnología de Sensores Remotos/métodos , Persona de Mediana Edad
2.
Br J Anaesth ; 118(1): 90-99, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28039246

RESUMEN

BACKGROUND: Service models for gastrointestinal endoscopy sedation must be safe, as endoscopy is the most common procedure performed under sedation in many countries. The aim of this prospective cohort study was to determine the patient risk profile, and incidence of and risk factors for significant unplanned events, in adult patients presenting for gastrointestinal endoscopy in a group of university-affiliated hospitals where most sedation is managed by anaesthetists. METHODS: Patients aged ≥18 yr presenting for elective and emergency gastrointestinal endoscopy under anaesthetist-managed sedation at nine hospitals affiliated with the University of Melbourne, Australia, were included. Outcomes included significant airway obstruction, hypoxia, hypotension and bradycardia; unplanned tracheal intubation; abandoned procedure; advanced life support; prolonged post-procedure stay; unplanned over-night admission and 30-day mortality. RESULTS: 2,132 patients were included. Fifty percent of patients were aged >60 yr, 50% had a BMI >27 kg m -2, 42% were ASA physical status III-V and 17% were emergency patients. The incidence of significant unplanned events was 23.0% (including significant hypotension 11.8%). Significant unplanned intraoperative events were associated with increasing age, BMI <18.5 kg m -2, ASA physical status III-V, colonoscopy and planned tracheal intubation. Thirty-day mortality was 1.2% (0.2% in electives and 6.0% in emergencies) and was associated with ASA physical status IV-V and emergency status. CONCLUSIONS: Patients presenting for gastrointestinal endoscopy at a group of public university-affiliated hospitals where most sedation is managed by anaesthetists, had a high risk profile and a substantial incidence of significant unplanned intraoperative events and 30-day mortality.


Asunto(s)
Sedación Consciente/efectos adversos , Endoscopía Gastrointestinal/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Endoscopía Gastrointestinal/mortalidad , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Seguridad del Paciente , Estudios Prospectivos , Adulto Joven
3.
Int Psychogeriatr ; 25(12): 2067-75, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23962713

RESUMEN

BACKGROUND: There are still substantial uncertainties over best practice in delirium care. The European Delirium Association (EDA) conducted a survey of its members and other interested parties on various aspects of delirium care. METHODS: The invitation to participate in the online survey was distributed among the EDA membership. The survey covered assessment, treatment of hyperactive and hypoactive delirium, and organizational management. RESULTS: A total of 200 responses were collected (United Kingdom 28.6%, Netherlands 25.3%, Italy 15%, Switzerland 9.7%, Germany 7.1%, Spain 3.8%, Portugal 2.5%, Ireland 2.5%, Sweden 0.6%, Denmark 0.6%, Austria 0.6%, and others 3.2%). Most of the responders were doctors (80%), working in geriatrics (45%) or internal medicine (14%). Ninety-two per cent of the responders assessed patients for delirium daily. The most commonly used assessment tools were the Confusion Assessment Method (52%) and the Delirium Observation Screening Scale (30%). The first-line choice in the management of hyperactive delirium was a combination of non-pharmacological and pharmacological approaches (61%). Conversely, non-pharmacological management was the first-line choice in hypoactive delirium (67%). Delirium awareness (34%), knowledge (33%), and lack of education (13%) were the most commonly reported barriers to improving the detection of delirium. Interestingly, 63% of the responders referred patients after an episode of delirium to a follow-up clinic. CONCLUSIONS: This is the first systematic survey involving an international group of specialists in delirium. Several areas of lack of consensus were found. These results emphasise the importance of further research to improve care of this major unmet medical need.


Asunto(s)
Delirio/terapia , Psiquiatría Geriátrica/estadística & datos numéricos , Recolección de Datos , Europa (Continente)/epidemiología , Psiquiatría Geriátrica/métodos , Psiquiatría Geriátrica/normas , Humanos , Guías de Práctica Clínica como Asunto/normas , Encuestas y Cuestionarios
4.
Clin Microbiol Infect ; 19(12): 1174-80, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23438068

RESUMEN

A number of different methods exist to assess clinical stability, a key component of pneumonia management. We compared the prognostic value of different stability criteria through a secondary analysis of the Edinburgh pneumonia study database. We studied four clinical stability criteria (Halm's criteria, the ATS criteria, CURB and 50% or more decrease in C-reactive protein from baseline). Outcomes included 30-day mortality, need for mechanical ventilation or vasopressor support (MV/VS), development of a complicated pneumonia, and a combined outcome of the above. A total of 1079 patients (49.8% male), with a median age of 68 years (IQR 53-80), were included. Ninety-three patients (8.6%) died by day 30, 91 patients (8.4%) required MV/VS and 99 patients (9.2%) developed a complicated pneumonia. Patients with increasing severity of pneumonia on admission, assessed by both CURB-65 and PSI, took a progressively longer time to achieve clinical stability assessed by any method (p < 0.001 for all criteria). Halm's criteria had the highest area under the curve (AUC) for prediction of 30-day mortality (AUC 0.95 (0.94-0.96)), need for MV/VS (AUC 0.96 (0.95-0.97)) and combined adverse outcome (AUC 0.96 (0.95-0.97)). C-reactive protein had the highest area under the curve for complicated pneumonia (AUC 0.96 (0.95-0.97)). Adding C-reactive protein to Halm's criteria increased the area under the curve, but the difference was only statistically significant for complicated pneumonia. All of the criteria performed well in predicting adverse outcomes in patients with pneumonia. Halm's criteria performed best when identifying patients at low risk of complications.


Asunto(s)
Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/mortalidad , Neumonía/diagnóstico , Neumonía/mortalidad , Anciano , Proteína C-Reactiva/metabolismo , Infecciones Comunitarias Adquiridas/terapia , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Neumonía/complicaciones , Neumonía/terapia , Pronóstico , Estudios Prospectivos , Respiración Artificial , Índice de Severidad de la Enfermedad
5.
Gastroenterology ; 121(6): 1437-50, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11729123

RESUMEN

BACKGROUND & AIMS: Cdx2 is critical in intestinal proliferation and differentiation. Modulation of Cdx2 function in response to cellular signaling is to be elucidated. We hypothesize that phosphorylation of the Cdx2 activation domain can modulate its function. METHODS: The Cdx2 activation domain was delineated in transient transfections using different portions of Cdx2 fused to the Gal4-DNA binding domain. In vivo phosphorylation was studied by metabolic labeling with (32)P-orthophosphate. To study a potential phosphorylation site, polyclonal antibodies were generated: CNL was raised against amino acids 54-66 of Cdx2 and P-Cdx2-S60 against the same epitope in which serine 60 was phosphorylated. RESULTS: A critical region for transactivation resides within amino acids 60-70. Substitution of serine 60 with alanine reduces incorporation of (32)P-orthophosphate substantially. S60-phosphorylation decreases Cdx2 transactivation. Phosphorylation of serine 60 can be inhibited with the mitogen-activated protein kinase inhibitors PD98059 or UO126. P-Cdx2-S60 recognizes phosphorylated serine 60 mainly in proliferative compartment of the intestinal epithelial layer. In contrast, CNL recognizes Cdx2 predominantly in the differentiated compartment. CONCLUSIONS: The Cdx2 activation domain is phosphorylated at serine 60 via the mitogen-activated protein kinase pathway. S60-phosphorylated and S60-nonphosphorylated Cdx2 have different transcriptional activity, as well as different spatial expression patterns in the intestinal epithelium.


Asunto(s)
Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Activación Transcripcional/fisiología , Secuencia de Aminoácidos/genética , Animales , Factor de Transcripción CDX2 , División Celular/fisiología , Línea Celular , Núcleo Celular/metabolismo , Colon/citología , Colon/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Homeodominio/química , Humanos , Inmunohistoquímica , Intestino Delgado/citología , Intestino Delgado/metabolismo , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , Fosforilación , Estructura Terciaria de Proteína , Serina/metabolismo , Transactivadores
6.
Methods Mol Med ; 61: 99-106, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-22323254

RESUMEN

The use of antisense oligonucleotides as both research tools and therapeutic molecules has emerged as a powerful alternative to small molecule inhibitors. Antisense oligonucleotides are short pieces of chemically modified DNA designed to hybridize to specific mRNA sequences present in the target gene. The oligonucleotide interaction with the targeted mRNA can lead to inhibition in the translation of the protein encoded by the targeted transcript through a variety of reasonably well-characterized mechanisms (1-3).

7.
Nat Biotechnol ; 17(11): 1097-100, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10545916

RESUMEN

Resistance to apoptosis, which plays an important role in tumors that are refractory to chemotherapy, is regulated by the ratio of antiapoptotic to proapoptotic proteins. By manipulating levels of these proteins, cells can become sensitized to undergo apoptosis in response to chemotherapeutic agents. Alternative splicing of the bcl-x gene gives rise to two proteins with antagonistic functions: Bcl-xL, a well-characterized antiapoptotic protein, and Bcl-xS, a proapoptotic protein. We show here that altering the ratio of Bcl-xL to Bcl-xS in the cell using an antisense oligonucleotide permitted cells to be sensitized to undergo apoptosis in response to ultraviolet B radiation and chemotherapeutic drug treatment. These results demonstrate the ability of a chemically modified oligonucleotide to alter splice site selection in an endogenous gene and illustrate a powerful tool to regulate cell survival.


Asunto(s)
Empalme Alternativo , Apoptosis/genética , Oligonucleótidos Antisentido/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Mensajero/metabolismo , Northern Blotting , Línea Celular , Regulación de la Expresión Génica , Humanos , Oligonucleótidos Antisentido/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína bcl-X
8.
Oncogene ; 18(31): 4495-504, 1999 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-10442640

RESUMEN

The epidermis is continually exposed to harmful mutagens that have the potential to cause DNA damage. To protect the skin from accumulating mutated cells, keratinocytes have developed a highly regulated mechanism of eliminating damaged cells through apoptosis. Bcl-xL is a well-described cell survival protein that when overexpressed in skin can protect keratinocytes from UV radiation-induced apoptosis. To begin to unravel the complex mechanisms that keratinocytes use to survive, we wanted to characterize the role of endogenous Bcl-xL in protecting cells from death. In this study, we describe the development and characterization of an antisense inhibitor to Bcl-xL. We show that this inhibitor reduces Bcl-xL RNA and protein in a concentration-dependent, sequence-specific manner. Furthermore, treatment of keratinocytes and epithelial cells with this inhibitor sensitizes these cells to UV-B radiation and cisplatinum treatment-induced apoptosis. Thus, these results offer direct evidence that Bcl-xL is critical in the protection of skin and epithelial cells from apoptosis and provide a basis for the role of Bcl-xL in keratinocyte and epithelial cell survival.


Asunto(s)
Apoptosis/fisiología , Ciclo Celular/fisiología , Células Epiteliales/citología , Queratinocitos/citología , Oligonucleótidos Antisentido/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Rayos Ultravioleta , Apoptosis/efectos de los fármacos , Secuencia de Bases , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Células Cultivadas , Cisplatino/farmacología , Clonación Molecular , Diploidia , Células Epiteliales/efectos de los fármacos , Células Epiteliales/efectos de la radiación , Células HL-60 , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Neoplasias Pulmonares , Oligonucleótidos Antisentido/química , Proteínas Proto-Oncogénicas c-bcl-2/genética , Piel/citología , Transfección , Células Tumorales Cultivadas , Proteína bcl-X
9.
Pharmacol Ther ; 82(2-3): 427-35, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10454217

RESUMEN

The dramatic increase in recent years of both the amount and rate of accumulation of novel genomic sequence information has generated enormous opportunities for the development of new classes of drugs. For these opportunities to be fully capitalized upon, investigators must choose molecular targets for drug development that are likely to yield attractive therapeutic profiles. This will require rapid and effective determination of gene functions in multiple cellular settings. The development of antisense oligonucleotides as specific inhibitors of gene expression should allow such determination of gene function. In addition, the antisense oligonucleotides themselves will likely prove useful as drugs. In this review, we discuss some of the issues surrounding the use of antisense oligonucleotides as research tools to help elucidate gene function, and highlight some of the approaches that can be taken to generate and use effective antisense reagents.


Asunto(s)
Oligonucleótidos Antisentido/antagonistas & inhibidores , Oligonucleótidos Antisentido/uso terapéutico , Proteínas/genética , Empalme del ARN/genética , Predicción , Oligonucleótidos Antisentido/química , Proteínas/química
10.
J Biol Chem ; 274(16): 11245-52, 1999 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-10196212

RESUMEN

In this study, we utilized potent antisense oligonucleotides to examine the role of two Bcl-2 family members found in human umbilical vein endothelial cells (HUVEC). The first, A1, is thought to be a TNF-alpha-inducible cytoprotective gene, and the second, Bcl-XL, is constitutively expressed. Inhibition of the constitutive levels of Bcl-XL caused 10-25% of the cell population to undergo apoptosis and increased the susceptibility of cells to treatment with low concentrations of staurosporin or ceramide. The caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe)-CH2 prevented DNA fragmentation and DeltaYm loss caused by Bcl-XL inhibition or Bcl-XL inhibition combined with staurosporin. However, disruption of DeltaYm caused by Bcl-XL inhibition combined with ceramide treatment was not inhibited by benzyloxycarbonyl-Val-Ala-Asp(OMe)-CH2, although DNA fragmentation was completely prevented. Taken together, these results demonstrate a direct protective role for Bcl-XL under normal resting conditions and under low level apoptotic challenges to HUVEC. Furthermore, Bcl-XL protects cells from caspase-dependent and -independent mechanisms of DeltaYm disruption. In contrast to Bcl-XL, A1 inhibition did not show a marked effect on the susceptibility of HUVEC to undergo apoptosis in response to TNF-alpha, ceramide, or staurosporin. These results demonstrate that although A1 may be a cytoprotective gene induced by TNF-alpha, it is not primarily responsible for HUVEC resistance to this cytokine.


Asunto(s)
Apoptosis/fisiología , Proteínas de Unión al ADN/fisiología , Endotelio Vascular/metabolismo , Proteínas de Homeodominio , Oligonucleótidos Antisentido/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Proteínas Represoras , Proteínas de Saccharomyces cerevisiae , Apoptosis/efectos de los fármacos , Secuencia de Bases , Caspasas/metabolismo , Células Cultivadas , Ceramidas/farmacología , Proteínas de Unión al ADN/genética , Endotelio Vascular/citología , Endotelio Vascular/enzimología , Humanos , Potenciales de la Membrana/efectos de los fármacos , Antígenos de Histocompatibilidad Menor , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/efectos de los fármacos , Proteína de Replicación C , Estaurosporina/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Proteína bcl-X
11.
J Biol Chem ; 274(11): 7196-9, 1999 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-10066780

RESUMEN

Cdx2 encodes for a homeodomain protein that is expressed in intestinal epithelial cells. The Cdx2 protein triggers intestinal differentiation in cell lines and is necessary for maintenance of the intestinal phenotype in mice. CBP (cAMP response element-binding protein) is a transcriptional co-activator that interacts with many transcription factors and components of the basal transcriptional machinery. In this study, we demonstrate that CBP is markedly induced upon differentiation of the Caco-2 intestinal cell line and augments Cdx2-dependent transcriptional activity. Cdx2 interacts with the amino-terminal domain of CBP, and the two proteins coexist in vivo within the same nuclear protein complex. Moreover, expression of the CBP domain that interacts with Cdx2 acts as a dominant-negative inhibitor of transcriptional activation by Cdx2. These findings demonstrate a direct interaction between an intestinal homeodomain protein and CBP and suggest that CBP participates in the network of transcriptional proteins that direct intestinal differentiation.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Homeodominio/metabolismo , Proteínas Nucleares/metabolismo , Transcripción Genética , Células 3T3 , Animales , Proteínas Potenciadoras de Unión a CCAAT , Células CACO-2 , Diferenciación Celular , División Celular , Humanos , Ratones , Unión Proteica
12.
Curr Opin Drug Discov Devel ; 2(2): 147-51, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19649941

RESUMEN

Numerous human diseases arise from mutations that result in aberrant RNA splicing. To date, traditional therapeutic approaches have not been successful in targeting these mutations and restoring correct splicing. Antisense oligonucleotides may provide a novel and effective way to restore correct splicing in mutant genes. Historically, antisense oligonucleotides have been used to decrease mRNA transcripts of disease gene products through an RNase H-dependent mechanism. Through chemical modifications of antisense oligonucleotides, it has been possible to generate compounds that bind to specific mRNA sequences with high affinity, yet do not cause the degradation of the RNA transcript. By directing chemically-modified oligonucleotides to regions of the pre-mRNA important for splicing, it may be possible to inhibit splicing at mutant splice sites. This novel and relatively unexplored application of antisense technology could be of tremendous therapeutic benefit in the treatment of human disease.

13.
Gastroenterology ; 113(2): 478-86, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9247467

RESUMEN

BACKGROUND & AIMS: CDX1 is an intestine-specific transcription factor expressed early in intestinal development that may be involved in regulation of proliferation and differentiation of intestinal epithelial cells. We examined the pattern of CDX1 protein expression in metaplastic and neoplastic tissue to provide insight into its possible role in abnormal differentiation. METHODS: Tissue samples were stained by immunohistochemistry using an affinity-purified, polyclonal antibody against a peptide epitope of CDX1. RESULTS: Specific nuclear staining was found in epithelial cells of the small intestine and colon. Esophagus and stomach did not express CDX1 protein; however, adjacent areas of intestinal metaplastic tissue intensely stained for CDX1. Adenocarcinomas of the stomach and esophagus had both positive and negative nuclear staining for CDX1. Colonic epithelial cells in adenomatous polyps and adenocarcinomas had a decreased intensity of staining compared with normal colonic crypts in the same specimen. CONCLUSIONS: CDX1 may be important in the transition from normal gastric and esophageal epithelium to intestinal-type metaplasia. The variability in expression of CDX1 in gastric and esophageal adenocarcinomas suggests more than one pathway in the development of these carcinomas. The decrease of CDX1 in colonic adenocarcinomas may indicate a role for CDX1 in growth regulation and in the maintenance of the differentiated phenotype.


Asunto(s)
Adenocarcinoma/química , Adenoma/química , Proteínas Aviares , Colon/química , Neoplasias del Colon/química , Neoplasias Esofágicas/química , Proteínas de Homeodominio/análisis , Intestino Delgado/química , Neoplasias Gástricas/química , Células 3T3 , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenoma/metabolismo , Adenoma/patología , Animales , Western Blotting , Transformación Celular Neoplásica/patología , Colon/metabolismo , Colon/patología , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , ADN/análisis , ADN/química , ADN/genética , ADN de Neoplasias/análisis , ADN de Neoplasias/química , ADN de Neoplasias/genética , Células Epiteliales , Epitelio/química , Epitelio/patología , Epítopos , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/patología , Metaplasia , Ratones , Microvellosidades/patología , Fenotipo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología
14.
J Endod ; 23(8): 508-12, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9587321

RESUMEN

Coronal microleakage may be a major factor in the etiology of treatment failure. This study examined the effect of obturation technique, sealer, and the presence of smear layer on coronal microleakage. Two hundred extracted human teeth were assigned to 20 treatment groups. Groups were examined with the smear layer present or smear layer removed (17% REDTA). Access cavities were exposed to artificial saliva then Pelikan Ink. Teeth were cleared and linear dye penetration measured. When all groups with the smear layer removed were compared with all groups with the smear layer present, significantly less leakage was seen when the smear layer was removed. Ultrafil displayed significantly more leakage than all other groups. Vertical compaction of lateral condensation and Thermafil obturations significantly reduced leakage. AH-26 displayed significantly less leakage than Roth's 811 sealer. These results indicate that removal of the smear layer, the use of AH-26, and vertical compactin have cumulative effects in reducing coronal leakage.


Asunto(s)
Filtración Dental/etiología , Materiales de Obturación del Conducto Radicular/uso terapéutico , Obturación del Conducto Radicular/métodos , Capa de Barro Dentinario , Corona del Diente , Análisis de Varianza , Filtración Dental/prevención & control , Técnica de Dilución de Colorante , Humanos , Técnicas In Vitro , Obturación del Conducto Radicular/instrumentación , Obturación del Conducto Radicular/estadística & datos numéricos , Insuficiencia del Tratamiento
15.
Artículo en Inglés | MEDLINE | ID: mdl-9195628

RESUMEN

UNLABELLED: The success of root canal treatment can be subjectively evaluated both clinically and radiographically. Normally, the recall radiograph is the main factor in evaluating success or failure. OBJECTIVES: This study evaluated periapical areas of root canal treated teeth by correlating radiographic and histologic findings. STUDY DESIGN: Jaws were resected from cadavers and radiographed. Those teeth that had received root canal treatment were evaluated for success or failure based on radiographic criteria. Teeth and surrounding bone were then removed en bloc and prepared for light microscopy. Untreated teeth without periapical pathosis were examined as controls. RESULTS: Root canal treated teeth classified as failures were found to consistently have inflammatory resorptive lesions at the periapices. In contrast, those treated teeth classified as radiographically successful showed varying reactions ranging from normal uninflamed to mildly inflamed. CONCLUSIONS: Those classified as failure showed consistent inflammation. However, the majority of our examined treated teeth were radiographically normal and exhibited no periapical inflammation.


Asunto(s)
Fracaso de la Restauración Dental , Periodontitis Periapical/patología , Tratamiento del Conducto Radicular , Diente no Vital/diagnóstico por imagen , Cadáver , Humanos , Evaluación de Resultado en la Atención de Salud , Periodontitis Periapical/diagnóstico por imagen , Periodontitis Periapical/etiología , Radiografía , Tratamiento del Conducto Radicular/efectos adversos , Diente no Vital/patología
16.
Nucleic Acids Res ; 25(12): 2293-300, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9171078

RESUMEN

Cdx2 is a caudal-related homeodomain transcription factor that is expressed in complex patterns during mouse development and at high levels in the intestinal epithelium of adult mice. Cdx2 activates transcription of intestinal gene promoters containing specific binding sites. Moreover, Cdx2 has been shown to induce intestinal differentiation in cell lines. In this study, we show that Cdx2 is able to bind to two well defined enhancer elements in the HoxC8 gene. We then demonstrate that Cdx2 is able to activate transcription of heterologous promoters when its DNA binding element is placed in an enhancer context. Furthermore, the ability to activate enhancer elements is cell-line dependent. When the Cdx2 activation domain was linked to the Gal4 DNA binding domain, the chimeric protein was able to activate Gal4 enhancer constructs in an intestinal cell line, but was unable to activate transcription in NIH3T3 cells. These data suggest that there are cell-specific factors that allow the Cdx2 activation domain to function in the activation of enhancer elements. We hypothesize that either a co-activator protein or differential phosphorylation of the activation domain may be the mechanism for intestinal cell line-specific function of Cdx2 and possibly in other tissues in early development.


Asunto(s)
Elementos de Facilitación Genéticos , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/metabolismo , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción , Células 3T3 , Animales , Sitios de Unión , Factor de Transcripción CDX2 , Diferenciación Celular , Neoplasias del Colon , Cartilla de ADN , Proteínas de Unión al ADN , Proteínas Fúngicas/biosíntesis , Genes Reporteros , Proteínas de Homeodominio/genética , Humanos , Luciferasas/biosíntesis , Ratones , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/metabolismo , Transactivadores , Activación Transcripcional , Transfección , Células Tumorales Cultivadas
17.
DNA Cell Biol ; 16(12): 1419-28, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9428790

RESUMEN

Intestinal phospholipase A/lysophospholipase (IPAL) is an intestine-specific brush-border enzyme expressed during development and along the intestinal crypt-villus axis in a pattern similar to another well characterized brush-border enzyme, sucrase-isomaltase (SI). A tissue-specific DNase I hypersensitive site was identified in chromatin from intestinal nuclei immediately upstream from the transcriptional start site of the IPAL gene. Footprinting analysis showed that two DNA elements within the IPAL promoter were protected by intestinal nuclear proteins. The IPAL-FP1 element was shown to be a monomer binding site for Cdx1 and Cdx2, intestine-specific homeobox proteins. Moreover, this site was important for transcriptional activation of the promoter in intestinal cell lines via interaction with Cdx proteins. Nuclear proteins from both liver and intestine interacted with the IPAL-FP2 element, forming a complex consistent with binding to HNF1. Cdx and HNF1 binding sites have also been shown to be the two major regulatory elements responsible for transcriptional activation of the SI gene promoter, which directs intestine-specific transcription in transgenic mice. These findings suggest that enterocyte genes that are expressed in similar developmental patterns may be regulated by the interaction of common DNA elements and their associated transcription factors.


Asunto(s)
Proteínas Aviares , Proteínas de Unión al ADN , Intestino Delgado/enzimología , Lisofosfolipasa/genética , Proteínas Nucleares , Complejo Sacarasa-Isomaltasa/genética , Animales , Secuencia de Bases , Sitios de Unión , Factor de Transcripción CDX2 , Clonación Molecular , Huella de ADN , Desoxirribonucleasa I/metabolismo , Factor Nuclear 1 del Hepatocito , Factor Nuclear 1-alfa del Hepatocito , Factor Nuclear 1-beta del Hepatocito , Proteínas de Homeodominio/metabolismo , Humanos , Intestino Delgado/citología , Lisofosfolipasa/metabolismo , Ratones , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Conejos , Secuencias Reguladoras de Ácidos Nucleicos , Complejo Sacarasa-Isomaltasa/metabolismo , Transactivadores , Factores de Transcripción/metabolismo , Transcripción Genética
18.
J Arthroplasty ; 11(2): 157-62, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8648309

RESUMEN

The low-wear characteristics of cobalt-chrome femoral heads matched with the excellent biocompatibility and low modulus of titanium alloy femoral stems constitute the preferred combination used by many orthopaedic surgeons performing total hip arthroplasty. The combination of these materials in a synovial fluid environment, however, has proven to result in extensive crevice corrosion and metallosis of the surrounding tissues. This study investigates an alternative to the conventional mating of dissimilar metals at the head-neck junction. Five cobalt-chrome heads premated with titanium alloy sleeves were investigated by gross examination, dissecting microscopy, and scanning electron microscopy. Examination by both gross examination and dissecting microscope revealed no signs of corrosion. Scanning electron microscope examination revealed slight crevice corrosion in the only head with a +15-mm neck length.


Asunto(s)
Aleaciones , Aleaciones de Cromo , Prótesis de Cadera , Complicaciones Posoperatorias/prevención & control , Titanio , Corrosión , Humanos , Microscopía Electrónica de Rastreo , Complicaciones Posoperatorias/patología , Diseño de Prótesis , Falla de Prótesis , Propiedades de Superficie
20.
J Arthroplasty ; 10(5): 661-6, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9273379

RESUMEN

The number of patients requiring revision total hip arthroplasty continues to increase each year. Accurate preoperative planning is a key factor in obtaining a good result. Radiographs provide little information concerning the actual extent of the acetabular defects. Computed tomography-generated models of the acetabulum can provide the surgeon with accurate information concerning the size and location of the defects. Evaluation of radiographs and models in 24 cases showed that radiographs alone failed to detect all 13 anterior wall defects (P < .001), 8 of 18 posterior wall defects (44.4%, P < .001), and 8 of 19 segmental central defects (42%, P < .001), all of which were easily identified with the models. This study showed that preoperative planning based on the foam models accurately predicted the actual implant used in 22 of 24 cases (92%).


Asunto(s)
Acetábulo/diagnóstico por imagen , Prótesis de Cadera , Procesamiento de Imagen Asistido por Computador , Adulto , Anciano , Anciano de 80 o más Años , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Tomografía Computarizada por Rayos X
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