RESUMEN
INTRODUCTION: The aim of this study was to evaluate the cytotoxic effects of three different light-cured orthodontic composites. MATERIAL AND METHODS: Light Bond (Reliance orthodontic products), Grengloo (Ormco corporation), and Kurasper F (Kuraray Europe GmbH) were selected for the experiment. Specimens were prepared according to the manufacturers' instructions, measuring 5 mm in diameter and 2 mm in thickness. Fibroblast cells were obtained from healthy gingival connective tissues. The composite cylinders were incubated in Dulbecco's modified Eagle's culture medium for 72 h according to ISO 10993-5 standards. The xCELLigence method was used to evaluate fibroblast cell vitality. After seeding 200 mL of the cell suspensions into the wells (20,000 cells/well) of the E-plate 96, gingival fibroblasts were treated with bioactive components released by the orthodontic composite materials and monitored every 15 min for 121 h. RESULTS: There were no significant differences between the human gingival fibroblast (HGF) cell indexes of the control and all testing groups (p > 0.05) at 24 and 48 h. Light Bond demonstrated statistically significant decrease in HGF index (p < 0.05) at 72 h, but there was no significant difference among the Kurasper F, Grengloo, and untreated control groups (p > 0.05). Light Bond (p < 0.001) and Grengloo (p < 0.05) groups had lower HGF cell index values when compared to untreated control group, but Kurasper F demonstrated no significant differences between the control groups at 96 h (p > 0.05). CONCLUSION: Orthodontic composite materials include biologically active components and may change oral tissue. So, biocompatible orthodontic bonding composites should be used.
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Resinas Acrílicas/toxicidad , Materiales Biocompatibles/toxicidad , Resinas Compuestas/toxicidad , Fibroblastos/efectos de los fármacos , Encía/efectos de los fármacos , Ácidos Fosfóricos/toxicidad , Cementos de Resina/toxicidad , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Encía/citología , Humanos , Ensayo de MaterialesRESUMEN
BACKGROUND AND OBJECTIVE: The implant surface plays a major role in the biological response to titanium dental implants. The aim of this study was to investigate levels of soluble receptor activator of nuclear factor-κB ligand (sRANKL), osteoprotegerin (OPG), bone morphogenetic protein-2 (BMP-2) and -7 (BMP-7) in the peri-implant crevicular fluid (PICF) of different implants during the osseointegration period. MATERIAL AND METHODS: Forty-seven patients (22 females and 25 males, mean age 47.34 ± 10.11) were included in this study. Forty-seven implants from two implant systems (group A1 (sandblasted acid-etched [SLA]-16), group A2 (hydrophilic-modified SLA [SLActive]-16), and group B (sandblasted acid-etched [SLA]-15) were placed using standard surgical protocols. PICF samples, plaque index, gingival index and probing depth measurements were obtained at 1 and 3 mo after surgery. PICF levels of sRANKL, OPG, BMP-2/-7 were analyzed by ELISA. RESULTS: No complications were observed during the healing period. No significant differences were observed in the PICF levels of sRANKL, OPG, BMP-2 and BMP-7 for all groups at any time point (p > 0.05). A significant decrease was observed in BMP-2 levels in group A1 (p < 0.05). A significant increase in BMP-7 levels was observed only for group A2 (p < 0.05). There was a strong negative correlation between OPG and gingival index and a negative correlation between BMP-7 and plaque index (p < 0.05). CONCLUSION: Considering the correlations between clinical and biochemical parameters, the levels of these cytokines in PICF during early healing of implants reflects the degree of peri-implant inflammation, rather than differences in the implant surfaces.
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Proteína Morfogenética Ósea 2/análisis , Proteína Morfogenética Ósea 7/análisis , Implantes Dentales , Diseño de Prótesis Dental , Líquido del Surco Gingival/química , Oseointegración/fisiología , Osteoprotegerina/análisis , Ligando RANK/análisis , Grabado Ácido Dental/métodos , Adulto , Grabado Dental/métodos , Índice de Placa Dental , Femenino , Estudios de Seguimiento , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Persona de Mediana Edad , Índice Periodontal , Bolsa Periodontal/clasificación , Propiedades de SuperficieRESUMEN
BACKGROUND: Achieving of moisture control especially gingival bleeding control is great challenge in clinical practice. Various hemostatic agents and techniques have been promoted for bleeding control during dental operation. But few studies have focused on the cytotoxicity of hemostatic solutions. AIM: The aim of this study was to evaluate cytotoxic effect of hemostatic agents on human gingival fibroblast cells by using real-time cell analysis method. MATERIALS AND METHODS: Two hemostatic solutions, Hemoban (Sultan Healthcare, Hackensack, NJ, USA) and Hemasatic Solutions (W.P. Dental, Hamburg, Germany) that includes mainly aluminum chloride were used with different concentration. Gingival fibroblasts were isolated from gingival connective tissue during crown lengthening surgery of systemically healthy subjects. Gingival fibroblasts were maintained with Dulbecco's modified eagle medium containing 10% fetal bovine serum. A real-time cell analyzer (RT-CES, xCELLigence; Roche Applied Science, Mannheim, Germany, and ACEA Biosciences, San Diego, CA, USA) was used to evaluate cell survival. After seeding 200 mL of the cell suspensions into the wells (10,000 cells/well) of the E-plate 96, gingival fibroblasts were treated with hemostatic solutions (1/2, 1/4 and 1/8 dilutions) and monitored every 15 minutes for 72 hours. For the proliferation experiments, the statistical analyses used were 1-way analysis of variance (ANOVA) and Tukey HSD multiple comparisons tests. RESULTS: According to statistically analysis, when evaluated at 48 and 72 hours, there were significant differences between the cell indexes of the control and all hemostatic agents groups (p < 0.001). Agent reduced cell index value significantly when compared to untreated control group. CONCLUSIONS: The results indicate that using of Hemoban or Hemostatic Solutions as astringent solutions have a significant cytotoxic effect on gingival fibroblast cells.
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Encía/efectos de los fármacos , Hemostáticos/farmacología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos/efectos de los fármacos , Encía/citología , HumanosRESUMEN
AIM: To investigate cell viability and gene expression of cementoblasts (OCCM.30) exposed to extractable components released by resin-based sealers with different chemical composition Hybrid Root Seal (HRS), SimpliSeal (SS), Real Seal (RS) and AH Plus (AH) and by a MTA-based sealers Tech Biosealer Endo (TBE). METHODOLOGY: Discs of all materials were prepared and allowed to set in humid conditions at 37° for 48 h. The discs were then incubated for 72 h at 37 °C to obtain material extracts (1/1) in DMEM. The extracts containing the components released by the sealers were filtered and other dilutions (1/2, 1/4) were prepared from the original solution (1/1). Original and diluted solutions were tested on the cementoblasts. Impedance-based real-time cell analysis (RTCA) was used to evaluate cell viability, quantitative real-time polymerase chain reaction (QRT-PCR) was used to examine the expression of mineralization-related genes (osteocalcin; OCN, Runt-related transcription factor-2; Runx2, collagen type 1; COL I, alkaline phosphatase; ALP). For statistical analysis, one-way analysis of variance (anova) and Tukey's honestly significant difference (HSD) tests were used. RESULTS: TBE (1/2), RS (1/2, 1/4), and HRS (1/2, 1/4) significantly decreased cell viability (P < 0.001). AH (1/2, 1/4) and SS (1/2, 1/4) had similar cell viability to the control at 30 h. All tested materials significantly decreased cell viability when compared to the control group except AH (1/2, 1/4) and SS (1/4) at 90 h. All of the tested sealers reduced COL I mRNA expressions when compared to the control. SS was associated with significant increases in OCN and Runx2 mRNA expressions when compared to the control (P < 0.001). Whereas all of the dilutions of TBE, RS and HRS significantly decreased BSP mRNA expressions (P < 0,001), 1/2 and 1/4 dilutions of SS increased BSP mRNA expression (P < 0,001). Except the 1/4 dilutions of AH and SS, all the sealer dilutions significantly reduced ALP mRNA expression in cementoblasts (P < 0,001). CONCLUSIONS: SimpliSeal and AH Plus resulted in more favourable response to cementoblasts because of their regulation potential on the mineralized tissue-associated protein's mRNA expressions.
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Compuestos de Calcio/farmacología , Fosfatos de Calcio/farmacología , Cemento Dental/efectos de los fármacos , Cementos de Resina/farmacología , Materiales de Obturación del Conducto Radicular/farmacología , Cemento de Silicato/farmacología , Silicatos/farmacología , Fosfatasa Alcalina/análisis , Compuestos de Aluminio/química , Compuestos de Aluminio/farmacología , Animales , Compuestos de Calcio/química , Fosfatos de Calcio/química , Línea Celular , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/análisis , Resinas Compuestas/química , Resinas Compuestas/farmacología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/análisis , Combinación de Medicamentos , Resinas Epoxi/química , Resinas Epoxi/farmacología , Humedad , Sialoproteína de Unión a Integrina/análisis , Ratones , Osteocalcina/análisis , Óxidos/química , Óxidos/farmacología , ARN Mensajero/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Cementos de Resina/química , Materiales de Obturación del Conducto Radicular/química , Cemento de Silicato/química , Silicatos/química , Temperatura , Factores de TiempoRESUMEN
AIM: To compare the effect of several materials on the attachment of periodontal ligament (PDL) fibroblasts to experimentally perforated root surfaces. METHODOLOGY: Root specimens (size 5 × 5 mm) were obtained from extracted human molar teeth and perforations with a 1 mm diameter were created. One group was kept as a control and the rest were repaired with the following materials: Amalgam, Dyract, IRM, Super Bond C&B and Mineral trioxide aggregate (MTA). PDL fibroblasts were placed at a density of 8 × 10(4) cells on the root specimens, incubated on tissue culture inserts (48 h) and then transferred to 48 well-plates. MTT assays were performed at 48 and 96 h for PDL fibroblast survival. Cell attachment was observed using confocal microscopy on days 2 and 5. Total RNAs from the root specimens were isolated on day 5 and type I collagen (COL I) and Runt-related transcription factor 2 (Runx2) mRNA expressions were checked using Quantitative-Polymerase Chain Reaction (QPCR). For the MTT assay and QPCR, one-way analysis of variance (anova) and Tukey HSD multiple comparison tests were used to compare the groups. RESULTS: Mineral trioxide aggregate resulted in a significantly higher cell density (P < 0.001). Dyract, IRM and Super Bond C&B groups had a lower cell density when compared with the control and MTA groups at 48 h (P < 0.001). Confocal microscopy revealed that, among the experimental groups, the MTA group had the largest viable cell population over the restoration site when compared with the other materials; however, reduced cell attachment was noted in all groups when compared with the control. Increased Runx2 mRNA expressions were noted in MTA (P < 0.001) and IRM (P < 0.01) groups when compared with control and other tested materials. COL I transcripts were increased in IRM (P < 0.01), D, C&B and MTA (P < 0.001) when compared with the control. CONCLUSION: Mineral trioxide aggregate provided a more favorable environment for PDL cell adhesion and growth.
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Fibroblastos/efectos de los fármacos , Ligamento Periodontal/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/uso terapéutico , Raíz del Diente/lesiones , Compuestos de Aluminio/uso terapéutico , Compuestos de Boro/uso terapéutico , Compuestos de Calcio/uso terapéutico , Adhesión Celular/efectos de los fármacos , Recuento de Células , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/análisis , Colorantes , Compómeros/uso terapéutico , Subunidad alfa 1 del Factor de Unión al Sitio Principal/análisis , Amalgama Dental/uso terapéutico , Combinación de Medicamentos , Fibroblastos/fisiología , Humanos , Ensayo de Materiales , Metacrilatos/uso terapéutico , Metilmetacrilatos/uso terapéutico , Microscopía Confocal , Óxidos/uso terapéutico , Ligamento Periodontal/citología , Reacción en Cadena en Tiempo Real de la Polimerasa , Silicatos/uso terapéutico , Sales de Tetrazolio , Tiazoles , Cemento de Óxido de Zinc-Eugenol/uso terapéuticoRESUMEN
The requirement for release of collateral ligaments to achieve a stable, balanced total knee replacement has been reported to arise in about 50% to 100% of procedures. This wide range reflects a lack of standardised quantitative indicators to determine the necessity for a release. Using recent advances in computerised navigation, we describe two navigational predictors which provide quantitative measures that can be used to identify the need for release. The first was the ability to restore the mechanical axis before any bone resection was performed and the second was the discrepancy in the measured medial and lateral joint spaces after the tibial osteotomy, but before any femoral resection. These predictors showed a significant association with the need for collateral ligament release (p < 0.001). The first predictor using the knee stress test in extension showed a sensitivity of 100% and a specificity of 98% and the second, the difference between medial and lateral gaps in millimetres, a sensitivity of 83% and a specificity of 95%. The use of the two navigational predictors meant that only ten of the 93 patients required collateral ligament release to achieve a stable, neutral knee.
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Artroplastia de Reemplazo de Rodilla/métodos , Deformidades Adquiridas de la Articulación/cirugía , Articulación de la Rodilla/cirugía , Ligamento Colateral Medial de la Rodilla/cirugía , Rango del Movimiento Articular/fisiología , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Rodilla/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Estrés Mecánico , Cirugía Asistida por Computador/instrumentación , Resultado del TratamientoRESUMEN
BACKGROUND AND OBJECTIVES: In this study, we investigated the effect of basic fibroblast growth factor (bFGF) and dexamethasone (Dex) on mRNA expressions of collagen (COL) type I, III and X, matrix metalloproteinases (MMP)-1, -2, -3 and -9 and tissue inhibitors of metalloproteinases (TIMP)-1 and -2, and also on mineralization and morphology of periodontal ligament (PDL) cells. MATERIAL AND METHODS: Periodontal ligament cells were obtained from premolar teeth extracted for orthodontic reasons. Periodontal ligament cells were cultured with Dulbecco's modified Eagle's medium containing: (1) 5% fetal bovine serum (FBS); (2) 5% FBS + ascorbic acid (AA, 50 microg/mL); (3) 5% FBS + Dex (10(-7) m) + AA; (4) 5% FBS + bFGF (10 ng/mL) + AA; or (5) 5% FBS + Dex (10(-7) m) + bFGF + AA. Cells within each group were evaluated for gene expression profile using semi-quantitative reverse transcriptase-polymerase chain reaction for COL I, III and X, MMP-1, -2, -3 and -9 and TIMP-1 and -2 on days 14 and 21 and for biomineralization by von Kossa stain in vitro on day 21. Images of PDL cells were examined using a phase contrast microscope. RESULTS: Basic fibroblast growth factor stimulated MMP-1, MMP-3 and MMP-9 mRNA expressions and inhibited TIMP-2 mRNA expression. Treatment of cells with Dex + bFGF led to downregulation of MMP-1, MMP-3 and MMP-9 transcripts. Whilst AA alone and Dex alone induced biomineralization of PDL cells, bFGF blocked the mineralization activity of the cells. In the Dex + bFGF group, more mineral nodules were noted when compared to AA alone and Dex alone groups. CONCLUSION: The addition of Dex to culture reversed bFGF-mediated inhibition of mineralization. Use of combined bFGF and Dex to regulate PDL cell function may be a good therapeutic option to obtain periodontal regeneration.
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Dexametasona/farmacología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Glucocorticoides/farmacología , Metaloproteinasas de la Matriz/efectos de los fármacos , Ligamento Periodontal/efectos de los fármacos , Inhibidores Tisulares de Metaloproteinasas/efectos de los fármacos , Calcificación Fisiológica/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Colágeno Tipo I/efectos de los fármacos , Colágeno Tipo III/efectos de los fármacos , Colágeno Tipo X/efectos de los fármacos , ADN/efectos de los fármacos , Regulación hacia Abajo , Perfilación de la Expresión Génica , Humanos , Metaloproteinasa 1 de la Matriz/efectos de los fármacos , Metaloproteinasa 2 de la Matriz/efectos de los fármacos , Metaloproteinasa 3 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Ligamento Periodontal/citología , ARN Mensajero/efectos de los fármacos , Inhibidor Tisular de Metaloproteinasa-1/efectos de los fármacos , Inhibidor Tisular de Metaloproteinasa-2/antagonistas & inhibidores , Inhibidor Tisular de Metaloproteinasa-2/efectos de los fármacosRESUMEN
The purpose of this study was to evaluate the effects of three different desensitizers on the cell viability and morphology of human gingival fibroblasts (HGF). Human gingival tissues were obtained from individuals who have clinically, healthy periodontium. HGF were grown at 37 degrees C in humidified atmosphere of 5% CO2 in Dulbecco's modified eagle's medium, supplemented with glutamine, penicillin, streptomycin, and 10% fetal bovine serum. The cells were treated with different concentrations (0.1, 0.3, and 0.5 microL/mL) of desensitizers (Gluma Desensitizer, Seal&Protect, and MicroPrime). After 24- and 48-h exposure to the desensitizer solutions, the viable cells were examined using a hemocytometer. To monitor HGF viability, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay was used and cell morphology was also observed at 48 h. Following exposure to concentrations of 0.1 microL/mL of test materials for 24 h, cell survival rates for Gluma Desensitizer (106%) and Micro Prime (62%) were not significantly different from the control, while it was significant for Seal&Protect (50%). Growing cells were significantly inhibited by all tested materials for 48 h (p < 0.05) in survival rates of 51, 47, and 31%, respectively. On the basis of the MTT assay, the cytotoxic effect of MicroPrime was more prominent, especially at high concentrations, than does Gluma Desensitizer and Seal&Protect. After exposure to Seal&Protect and MicroPrime, HGF became retracted, rounded in appearance and had loss of normal organization, leading to enlargement of intercellular space when compared with Gluma Desensitizer. As a conclusion, taking the limitations of an in vitro experiment into consideration, the cytotoxic effects were varied, depending on the chemical composition and exposure periods of the tested desensitizers.
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Bencetonio/toxicidad , Fibroblastos/efectos de los fármacos , Encía/citología , Glutaral/toxicidad , Metacrilatos/toxicidad , Cementos de Resina/toxicidad , Bencetonio/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Recubrimientos Dentinarios/farmacología , Recubrimientos Dentinarios/toxicidad , Encía/efectos de los fármacos , Glutaral/farmacología , Humanos , Metacrilatos/farmacología , Cementos de Resina/farmacologíaRESUMEN
BACKGROUND: It is thought that during development of the periodontium, dental follicle cells, when appropriately triggered, have the ability to differentiate into periodontal ligament fibroblasts, cementoblasts, and osteoblasts. However, the exact mechanisms/factors responsible for initiating cell differentiation are not defined. The purpose of this in vitro study was to further characterize follicle cells and to determine the effects of an enamel matrix-derived protein (EMD) on these cells. METHODS: Murine follicle cells, transformed with simian virus 40 (SV 40) T antigen-containing virus (SVF cells), were used. SVF cells were cultured in Dulbecco's modified Eagle's medium (DMEM) plus 2% fetal bovine serum (FBS) or 2% FBS plus EMD (100 microg/ml), with and without ascorbic acid (50 microg/ml). For proliferation assays, cells were plated at 500 cells/cm2 in 24-well plates and counted on days 3, 4, and 5. For Northern analysis, total RNA was isolated on days 8, 12, and 18. Induction of mineral nodules by SVF cells was determined by von Kossa staining. RESULTS: EMD had a significant proliferative effect on SVF cells, when compared with 2% FBS control. Based on investigations in situ, follicle cells at the time point used here do not express key mineral-associated markers, e.g., osteocalcin (OCN) or bone sialoprotein (BSP). Significantly, by day 12 in culture, Northern analysis indicated that the follicle cells expressed transcripts for BSP, OCN, and osteopontin (OPN). EMD increased OPN mRNA and decreased OCN mRNA expression. SVF cells were capable of inducing mineralization on day 18, but EMD blocked this activity. CONCLUSIONS: These results suggest the follicle cells have the capacity to act as cementoblasts or osteoblasts. Furthermore, EMD can regulate follicle cell activity, thus suggesting that epithelial-mesenchymal interactions may be important during development of periodontal tissues.
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Proteínas del Esmalte Dental/farmacología , Saco Dental/efectos de los fármacos , Análisis de Varianza , Animales , Antígenos Transformadores de Poliomavirus/inmunología , Northern Blotting , Calcificación Fisiológica/efectos de los fármacos , Recuento de Células , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular Transformada , Tamaño de la Célula/efectos de los fármacos , Colorantes , Cemento Dental/citología , Saco Dental/citología , Saco Dental/metabolismo , Fibroblastos/citología , Sialoproteína de Unión a Integrina , Ratones , Osteoblastos/citología , Osteocalcina/análisis , Osteopontina , Fosfoproteínas/análisis , Sialoglicoproteínas/análisis , Virus 40 de los Simios/inmunología , Estadística como AsuntoRESUMEN
BACKGROUND: Epidermolysis bullosa acquisita (EBA) is an uncommon, acquired, chronic subepidermal bullous disease. This report describes a case of EBA with gingival involvement. A 43-year-old woman with EBA was referred to our clinic for periodontal therapy because of gingival tenderness and bleeding. She has been on cyclosporin A therapy for the last 2 years. METHODS: Clinical findings were analyzed. Anterior gingivectomy operations were performed in 2 stages. The samples obtained during the surgery were examined using histopathologic, immunohistologic, and electronmicroscopic methods. Long-term effects of the surgical periodontal treatment on gingiva were evaluated both clinically and microscopically. RESULTS: The dentition displayed minimal enamel hypoplasia. Decayed, missing, and filled surfaces score was found to be elevated. Periodontal examination showed generalized diffuse gingival inflammation and gingival enlargement localized mainly to the anterior region. Nikolsky's sign was positive. However, wound healing was uneventful after the operations. Microscopic findings were similar to those obtained from the skin. Twenty-one months after the operations, Nikolsky's sign was negative and no remarkable gingival inflammation was noted. Microscopic examination revealed that the blisters were fewer in number and smaller in size. CONCLUSIONS: These results indicate that gingival tissues may also be involved in EBA. Uneventful wound healing after periodontal surgery in this case suggests that periodontal surgery can be performed in patients with EBA. Moreover, both our clinical and histopathologic findings imply that gingivectomy proves useful in maintaining gingival integrity in these patients. Our data may also suggest that the patients with EBA are highly likely to develop dental caries.
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Epidermólisis Ampollosa Adquirida/patología , Enfermedades de las Encías/patología , Hemorragia Gingival/patología , Adulto , Ciclosporina/uso terapéutico , Índice CPO , Hipoplasia del Esmalte Dental/patología , Epidermólisis Ampollosa Adquirida/cirugía , Femenino , Estudios de Seguimiento , Enfermedades de las Encías/cirugía , Hemorragia Gingival/cirugía , Hipertrofia Gingival/patología , Gingivectomía , Gingivitis/patología , Humanos , Inmunohistoquímica , Inmunosupresores/uso terapéutico , Microscopía Electrónica , Cicatrización de HeridasRESUMEN
Low-molecular-weight heparins (LMWH) are widely used as antithrombotic prophylactic pharmaceutical agents in orthopedic and general surgery. Their antithrombotic characteristics are expressed by plasma mediators such as anti-Xa. anti-IIa, and increased release of tissue factor pathway inhibitor (TFPI) from vascular endothelium. The purpose of this clinical research is to study the relation between plasma levels of these mediators and postoperative bleeding. Forty-one consecutive patients undergoing hip or knee arthroplasty (n = 36) and colectomy (n = 5) received the standard enoxaparin (a LMWH) dose preoperatively (general surgery) or immediately postoperatively (orthopedic surgery). Major bleeding was defined as a postoperative drop of > or = 5 g/dL) of hemoglobin. The authors observed that there was a linear relationship between an increase in free/total TFPI ratio levels and postoperative bleeding. When that ratio increased by >60%, the hemoglobin dropped to >5 g/dL (n = 13). This relationship between free/total TFPI ratio increase and postoperative bleeding was statistically significant (P < 0.001). Those who did not bleed (hemoglobin drop was less than 5 g/dL) (n = 28) had a ratio increase (if any) of less than 50%. However, the authors did not observe any statistical relationship between anti-Xa, anti-IIa, or prothrombin time and postoperative bleeding in patients receiving LMWH for deep vein thrombosis prophylaxis in orthopedic and general surgery patients. The authors recommend a pre- and postoperative ratio level measurement whenever major bleeding is anticipated, as adjustments of LMWH dose or frequency might be necessary.
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Enoxaparina/efectos adversos , Lipoproteínas/sangre , Procedimientos Ortopédicos/efectos adversos , Hemorragia Posoperatoria/inducido químicamente , Procedimientos Quirúrgicos Operativos/efectos adversos , Trombosis de la Vena/prevención & control , Anticoagulantes/sangre , Artroplastia/efectos adversos , Artroplastia/métodos , Biomarcadores/sangre , Pruebas de Coagulación Sanguínea , Colectomía/efectos adversos , Colectomía/métodos , Método Doble Ciego , Enoxaparina/administración & dosificación , Factor Xa/metabolismo , Inhibidores del Factor Xa , Hemoglobinas/metabolismo , Humanos , Estudios Prospectivos , Procedimientos Quirúrgicos Operativos/métodos , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/etiologíaRESUMEN
Low-molecular-weight heparins (LMWH) are widely used as antithrombotic prophylactic pharmaceutical agents in orthopedic and general surgery. Their antithrombotic characteristics are expressed by plasma mediators such as anti-Xa, anti-IIa, and increased release of tissue factor pathway inhibitor (TFPI) from vascular endothelium. The purpose of this clinical research is to study the relation between plasma levels of these mediators and postoperative bleeding. Forty-one consecutive patients undergoing hip or knee arthroplasty (n = 36) and colectomy (n = 5) received the standard enoxaparin (a LMWH) dose preoperatively (general surgery) or immediately postoperatively (orthopedic surgery). Major bleeding was defined as a postoperative drop of > or = 5 g/dL) of hemoglobin. The authors observed that there was a linear relationship between an increase in free/total TFPI ratio levels and postoperative bleeding. When that ratio increased by > 60%, the hemoglobin dropped to > 5 g/dL (n = 17). This relationship between free/total TFPI ratio increase and postoperative bleeding was statistically significant (P < 0.001). Those who did not bleed (hemoglobin drop was less than 5 g/dL) (n = 24) had a ratio increase (if any) of less than 50%. However, the authors did not observe any statistical relationship between anti-Xa, anti-IIa, or prothrombin time and postoperative bleeding in patients receiving LMWH for deep vein thrombosis prophylaxis in orthopedic and general surgery patients. The authors recommend a pre- and postoperative ratio level measurement whenever major bleeding is anticipated, as adjustments of LMWH dose or frequency might be necessary.
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Enoxaparina/efectos adversos , Lipoproteínas/sangre , Complicaciones Posoperatorias/sangre , Trombosis de la Vena/prevención & control , Biomarcadores/sangre , Método Doble Ciego , Monitoreo de Drogas/métodos , Enoxaparina/administración & dosificación , Inhibidores del Factor Xa , Fibrinolíticos/sangre , Hemorragia/inducido químicamente , Procedimientos Ortopédicos/efectos adversos , Procedimientos Ortopédicos/métodos , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Procedimientos Quirúrgicos Operativos/efectos adversos , Procedimientos Quirúrgicos Operativos/métodos , Factores de Tiempo , Trombosis de la Vena/tratamiento farmacológicoRESUMEN
When clinical data are insufficient to diagnose infection of bone or joints, nuclear scanning becomes crucial in making an accurate diagnosis. The efficacy of (99m)technetium antigranulocyte monoclonal antibody Fab' fragment (LeukoScan) is prospectively compared with (111)indium white blood cell and (99m)technetium methylene diphosphonate bone scans in 74 patients with suspected musculoskeletal infections. They were grouped according to site of suspected infection: 33 long bones, 23 prosthetic joints, and 18 diabetic feet. Sixty-two of these 74 patients had surgical verification with histopathology or culture. The remaining 12 patients had clinical followup as proof of absence of infection. The overall sensitivity of LeukoScan, (111)indium white blood cell, and (99m)technetium methylene diphosphonate bone scans was 93%, 85% and 92%, respectively. Specificity was 89%, 75% and 52%, and accuracy was 90%, 79% and 74%, respectively. The conclusion from this study is that LeukoScan is more accurate in detecting osteomyelitis, with better sensitivity and specificity in prosthetic joints. Compared with (111)indium white blood cell scans, LeukoScan++ gives superior images, and results are obtained in 1 to 6 hours without biohazard risk from handling blood products.
Asunto(s)
Pie Diabético/diagnóstico por imagen , Fragmentos Fab de Inmunoglobulinas , Osteomielitis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Tecnecio , Anciano , Femenino , Granulocitos/inmunología , Humanos , Radioisótopos de Indio , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Medronato de Tecnecio Tc 99mRESUMEN
Accurate early diagnosis of osteomyelitis is critical for optimal clinical management. Conventional radiology (X-rays, CT) and nuclear medicine scans (bone, gallium, and technetium/indium white blood cell [WBC]) have limitations and drawbacks. The monoclonal antibody (MAb) ImmuRAID-MN3 (Immunomedics Inc., Morris Plains, NJ), a 99m-Tc Antigranulocyte Fab' fragment, recognizes a surface glycoprotein NCA-90/95 shared by granulocytes, carcino-embryonic antigen (CEA), and meconium antigen (MA). Intravenous injection of radiolabeled MAb enables in vivo labeling of human granulocytes and targets infected lesions in the bone and throughout the body. Technetium labeled Fab' fragments rapidly clear the blood pool and high-quality images can be obtained the same day, as early as 1 h postinjection. Results at our institution on 13 patients with clinically suspected osteomyelitis of infected long bones, prostheses, and diabetic foot ulcers were compared with the surgical/bacteriological verification of the presence or absence of infection. The MAb scan showed six true positives, six true negatives, and one false negative (very low grade infection). The procedure was safe, no clinical or laboratory adverse reactions were encountered. The MAb fragments are markedly less immunogenic than whole IgG, resulting in lower induction of human antimouse antibody (HAMA) titers. No HAMA to this MAb fragment has been detected in 24 patients (data from multiple institutions). Our preliminary results suggest that 99m-Tc ImmuRAID-MN3 is highly accurate for detection of osteomyelitis. This study is part of an ongoing multiinstitutional project sponsored by Immunomedics, Inc. to evaluate the efficacy and safety of this radiopharmaceutical.
Asunto(s)
Anticuerpos Monoclonales , Granulocitos/inmunología , Inmunoconjugados , Fragmentos Fab de Inmunoglobulinas , Osteomielitis/diagnóstico , Compuestos de Tecnecio , Adulto , Anciano , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Proteins binding Escherichia coli heat-stable enterotoxin were isolated from the cytoskeleton of intestinal membranes using an affinity matrix of biotinylated ST immobilized on monomeric avidin-agarose. ST binding proteins were purified 343-fold using this affinity technique, with 7% of the initial binding activity recovered in these preparations. ST binding proteins isolated by affinity chromatography possessed a native and subunit molecular mass of 56 kDa. These preparations exhibited both high- and low-affinity binding sites for ST. Guanylate cyclase in extracts of the intestinal membrane cytoskeleton was completely recovered in fractions which did not associate with the affinity matrix. In addition, ST binding proteins isolated by affinity chromatography were devoid of guanylate cyclase activity. These data, taken together with those obtained previously with crude and partially purified receptors, suggest that ST binds to different proteins in intestinal membranes, some of which do not possess guanylate cyclase activity.
Asunto(s)
Toxinas Bacterianas/metabolismo , Enterotoxinas/metabolismo , Guanilato Ciclasa/análisis , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Receptores de Péptidos/aislamiento & purificación , Animales , Cromatografía de Afinidad , Cromatografía en Gel , Citoesqueleto/química , Escherichia coli , Proteínas de Escherichia coli , Unión Proteica , Ratas , Receptores de Enterotoxina , Receptores Acoplados a la Guanilato-Ciclasa , Receptores de Péptidos/químicaRESUMEN
1. Particulate guanylate cyclase and receptors for E. coli heat-stable enterotoxin were solubilized from the rat intestinal cytoskeletal compartment using Lubrol-PX and KCl. 2. Thirty to forty percent of the ST receptor and guanylate cyclase activities were extracted from the lipid layer with Lubrol-PX alone. 2. Seventy percent of the remaining activities were solubilized from the cytoskeleton with Lubrol-PX and KCl. 3. Guanylate cyclase solubilized from either compartment exhibited similar reaction kinetics. 4. Both high- and low-affinity classes of ST receptors were solubilized from the lipid and cytoskeleton compartments. 5. In the presence of ATP gamma S, ST selectively activated the guanylate cyclase solubilized from the cytoskeleton compared to that solubilized from the lipid bilayer. 6. Crosslinking experiments demonstrated a preferential solubilization of the 130 kDa receptor subunit from the cytoskeleton and the 56 kDa subunit from the lipid bilayer. 7. Development of a procedure to solubilize ST receptors and guanylate cyclase from the intestinal membrane cytoskeleton will permit purification and further detailed studies of the coupling of these activities.
Asunto(s)
Toxinas Bacterianas/metabolismo , Citoesqueleto/química , Enterotoxinas/metabolismo , Escherichia coli/química , Guanilato Ciclasa/aislamiento & purificación , Intestinos/ultraestructura , Receptores de Superficie Celular/aislamiento & purificación , Receptores de Péptidos , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Animales , Membrana Celular/ultraestructura , Activación Enzimática , Proteínas de Escherichia coli , Guanilato Ciclasa/química , Cinética , Membrana Dobles de Lípidos/química , Polidocanol , Polietilenglicoles , Cloruro de Potasio , Ratas , Receptores de Superficie Celular/química , Receptores de Superficie Celular/metabolismo , Receptores de Enterotoxina , Receptores Acoplados a la Guanilato-Ciclasa , SolubilidadRESUMEN
Novel high-affinity, low-capacity binding sites in intestinal membranes for the heat-stable toxin produced by Escherichia coli have been defined. The appearance of these sites is observed in the presence of physiological concentrations of NaCl in binding reactions. Scatchard analyses of equilibrium binding in the absence of NaCl demonstrated a single class of binding sites with KD = 1.9 x 10(-9) M and Bmax = 0.75 pmol/mg of protein. In contrast, similar experiments in the presence of NaCl demonstrated, in addition to the previously described low-affinity site, a high-affinity site with a KD of 2.1 x 10(-11) M and a Bmax of 73 fmol/mg of protein. Confirmation of the presence of high- and low-affinity sites was obtained in studies of the kinetics of ST binding. These sites exhibited similar dissociation but markedly different association kinetics. Determination of the association and dissociation constants permitted calculation of the KD's for the high- and low-affinity sites, which were 1.15 x 10(-11) M and 1.89 x 10(-9) M, respectively. These data agree closely with those obtained in studies of equilibrium binding. Furthermore, similar values for the KD's of these sites were obtained in experiments of competitive displacement of labeled ST, confirming the presence of two receptors for this toxin. Binding of ST to high-affinity sites is completely reversible and does not appear to be coupled to activation of particulate guanylate cyclase. In contrast, binding of ST to low-affinity sites appears to be partially reversible and may be coupled to activation of guanylate cyclase.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Toxinas Bacterianas/metabolismo , Enterotoxinas/metabolismo , Mucosa Intestinal/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores de Péptidos , Animales , Sitios de Unión , Unión Competitiva , Membrana Celular/química , Membrana Celular/metabolismo , Proteínas de Escherichia coli , Guanilato Ciclasa/metabolismo , Intestinos/química , Cinética , Ratas , Receptores de Superficie Celular/análisis , Receptores de Enterotoxina , Receptores Acoplados a la Guanilato-Ciclasa , Cloruro de Sodio/farmacologíaRESUMEN
Light activation of cyclic GMP hydrolysis in rod outer segments is mediated by a G-protein which is active in the GTP-bound form. Substitution of GTP with a nonhydrolyzable GTP analogue is thought to leave the G-protein in a persistently activated state, thereby prolonging the hydrolysis of cyclic GMP. Restoration of cyclic GMP concentration in the cell also depends upon GTP since it is the substrate for guanylate cyclase, but little is known about the effects of GTP analogues on this enzyme. We report here the effects of the analogues of GTP and ATP as inhibitors and substrates of rod disk membrane guanylate cyclase. The rate of cyclic GMP synthesis from GTP in rod disk membranes was about 50 pmol min-1 (nmol of rhodopsin)-1. Analogues of GTP and adenine nucleotides competitively inhibited the cyclase activity. The order of inhibition, with magnesium as metal cofactor, was ATP greater than GMP-PNP greater than AMP-PNP approximately GTP-gamma-S; with manganese, AMP-PNP was more inhibitory than GTP-gamma-S. The inhibition constants, with magnesium as cofactor, were 0.65-2.0 mM for GTP-gamma-S, 0.4-0.8 mM for GMP-PNP, 1.5-2.3 mM for AMP-PNP, and 0.07-0.2 mM for ATP. The fraction of cyclase activity inhibited by analogues was similar at 1 and 0.03 microM calcium. Besides inhibition of cyclase, the analogues also served as its substrates. GTP-gamma-S substituted GTP with about 85% efficiency while GMP-PNP and ATP were about 5 and 7% as efficient, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Guanilato Ciclasa/metabolismo , Nucleótidos/metabolismo , Segmento Externo de la Célula en Bastón/enzimología , Animales , Calcio/metabolismo , Bovinos , Guanilato Ciclasa/antagonistas & inhibidores , Hidrólisis , Magnesio/metabolismo , Manganeso/metabolismo , Especificidad por SustratoRESUMEN
A series of 4 patients with long overlooked, retained ureteral stents is presented to illustrate the variable, unpredictable, and at times, hazardous course of such patients. These cases are cited to re-emphasize the need for careful documentation, observation, and follow-up of patients in whom stents are placed.
Asunto(s)
Stents , Cateterismo Urinario/efectos adversos , Adolescente , Adulto , Catéteres de Permanencia , Humanos , Hidronefrosis/terapia , Masculino , Persona de Mediana Edad , UréterRESUMEN
The role of 48-kDa protein in visual transduction remains unresolved. Two hypotheses for its role in quenching the light activation of cyclic GMP cascade suggest that the protein binds to either phosphodiesterase or phosphorylated rhodopsin. Since the protein is also reported to bind ATP, we anticipated that the protein may have ATP hydrolyzing activity, and in analogy with the GTP-binding protein of the rod outer segments, such activity may be greatly enhanced by the elements of transduction cyclic GMP cascade, permitting the protein to function cyclically as GTP-binding protein does. We found that purified 48-kDa protein hydrolyzes ATP but at a slow rate of 0.04-0.05 per min. The Km for ATP is about 45-65 microM. The activity is inhibited noncompetitively by ADP with a Ki of about 50 microM. The ATPase activity of 48-kDa protein is not affected by rhodopsin, bleached rhodopsin, phosphorylated rhodopsin, unactivated cyclic GMP phosphodiesterase, or phosphodiesterase (PDE) activated by GMP PNP-bound G-protein. These data show that although 48-kDa protein has ATPase activity, lack of regulation of this activity by the elements of visual transduction makes it unlikely for this activity to have a role in quenching the light activation of cyclic GMP cascade.