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2.
J Dent Res ; 100(10): 1178-1185, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34235985

RESUMEN

In compromised bone conditions such as osteoporosis, developments of the implant surface are necessary to secure the stability of implants. This study investigated the effect of the surface porous titanium structure (PS) on the osseointegration of implants in osteoporotic bone. Bilateral ovariectomy (OVX) was performed in 4 female beagle dogs to induce osteoporosis for 32 wk. Success of induction was based on the evaluation of bone mineral density by Hounsfield units (HU) in computed tomography images. Posterior teeth in both mandibles were extracted 1 wk after OVX, and a total of 30 implants (15 implants in each group) were placed after 32 wk of osteoporosis induction. The control group implant underwent resorbable blast media (RBM) surface treatment, whereas the test group underwent RBM surface treatment in the coronal two-thirds and a PS added to the apical 3-mm portion. HU values in the mandibular trabecular bone, lumbar, and femoral head significantly decreased 32 wk after OVX, confirming osteoporotic condition after induction. Resonance frequency analysis and removal torque test showed comparable values between the 2 groups at 4 wk after implant placement. The surface topography of the implant after removal showed hard tissue integration at the PS in the test group. Bone-to-implant contact length was greater in the apical portion of the test group, although statistical significance was not found between the groups. Interthread bone area in the apical portion of the test group showed a significant increase compared to the control group (control: 0.059 ± 0.041 mm2, test: 0.121 ± 0.060 mm2, P = 0.028) with the histological feature of bone ingrowth at the PS. The findings of the study demonstrated that the surface PS could improve osteoconductivity in the osteoporotic trabecular bone by bone ingrowth at the pore space, thereby enhancing the osseointegration and stability of the implants.


Asunto(s)
Implantes Dentales , Osteoporosis , Animales , Densidad Ósea , Perros , Femenino , Humanos , Oseointegración , Osteoporosis/diagnóstico por imagen , Ovariectomía , Porosidad , Propiedades de Superficie , Titanio
3.
Acta Neurochir (Wien) ; 163(2): 423-440, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33354733

RESUMEN

BACKGROUND: Due to the lack of high-quality evidence which has hindered the development of evidence-based guidelines, there is a need to provide general guidance on cranioplasty (CP) following traumatic brain injury (TBI), as well as identify areas of ongoing uncertainty via a consensus-based approach. METHODS: The international consensus meeting on post-traumatic CP was held during the International Conference on Recent Advances in Neurotraumatology (ICRAN), in Naples, Italy, in June 2018. This meeting was endorsed by the Neurotrauma Committee of the World Federation of Neurosurgical Societies (WFNS), the NIHR Global Health Research Group on Neurotrauma, and several other neurotrauma organizations. Discussions and voting were organized around 5 pre-specified themes: (1) indications and technique, (2) materials, (3) timing, (4) hydrocephalus, and (5) paediatric CP. RESULTS: The participants discussed published evidence on each topic and proposed consensus statements, which were subject to ratification using anonymous real-time voting. Statements required an agreement threshold of more than 70% for inclusion in the final recommendations. CONCLUSIONS: This document is the first set of practical consensus-based clinical recommendations on post-traumatic CP, focusing on timing, materials, complications, and surgical procedures. Future research directions are also presented.


Asunto(s)
Lesiones Traumáticas del Encéfalo/cirugía , Conferencias de Consenso como Asunto , Craneotomía/normas , Procedimientos de Cirugía Plástica/normas , Humanos , Hidrocefalia/cirugía , Italia
4.
J Physiol Pharmacol ; 71(3)2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32991314

RESUMEN

Canine cloning is occasionally accompanied by abnormal sexual development. Some male donor cells produce cloned pups with female external genitalia and complete male gonadal dysgenesis, which is classified as an XY disorder of sex development (XY DSD). In this study, we examine the potential of 5-aza-2'-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, to reduce the phenotypic abnormality XY DSD in somatic cell nuclear transfer (SCNT)- derived pups. We used a 9-year-old normal male German Shepherd dog as a cell donor. Donor cells were treated with 10 nM 5-aza-dC for 4 days before being used for SCNT. At the same stage of cell development, significantly lower levels of DNA methylation of the sex-determining region Y (SRY) promoter was observed in the treated donor cells compared to that in the untreated cells (95.2% versus 53.3% on day 4 for the control and treated groups, respectively). No significant differences were observed in the control or treatment groups concerning fusion rate, pregnancy rate (30 days or entire period), the number of pups, or the incidence of XY DSD. However, more XY DSD dogs were observed in the control group (31.25%) than in the treatment group (14.29%). Hypermethylation of the SRY promoter was observed in the XY DSD cloned pups in both the treatment (84.8%) and control groups (91.1 ± 1.4%) compared to the methylation level in the phenotypically normal male pups of the treatment (23.2 ± 20.9%) and control groups (39.1 ± 20.1%). These results suggest that 5-aza-dC treatment of donor cells can reduce the methylation level of the SRY promoter in donor cells, and thus, 5-aza-dC is advantageous for reducing the incidence of XY DSD in canine cloning.


Asunto(s)
Clonación Molecular , Metilación de ADN , Enfermedades de los Perros/genética , Disgenesia Gonadal 46 XY/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Regiones Promotoras Genéticas , Procesos de Determinación del Sexo/genética , Proteína de la Región Y Determinante del Sexo/genética , Animales , Metilación de ADN/efectos de los fármacos , Metilasas de Modificación del ADN/antagonistas & inhibidores , Metilasas de Modificación del ADN/metabolismo , Decitabina/farmacología , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/patología , Perros , Inhibidores Enzimáticos/farmacología , Predisposición Genética a la Enfermedad , Disgenesia Gonadal 46 XY/tratamiento farmacológico , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/patología , Masculino , Técnicas de Transferencia Nuclear/efectos adversos , Fenotipo , Regiones Promotoras Genéticas/efectos de los fármacos
5.
Int J Dent ; 2016: 9393219, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27298621

RESUMEN

Purpose. To evaluate the soft tissue stability around single implants inserted to replace maxillary lateral incisors, using an innovative 3D method. Methods. We have used reverse-engineering software for the superimposition of 3D surface models of the dentogingival structures, obtained from intraoral scans of the same patients taken at the delivery of the final crown (S1) and 2 years later (S2). The assessment of soft tissues changes was performed via calculation of the Euclidean surface distances between the 3D models, after the superimposition of S2 on S1; colour maps were used for quantification of changes. Results. Twenty patients (8 males, 12 females) were selected, 10 with a failing/nonrestorable lateral incisor (test group: immediate placement in postextraction socket) and 10 with a missing lateral incisor (control group: conventional placement in healed ridge). Each patient received one immediately loaded implant (Anyridge®, Megagen, Gyeongbuk, South Korea). The superimposition of the 3D surface models taken at different times (S2 over S1) revealed a mean (±SD) reduction of 0.057 mm (±0.025) and 0.037 mm (±0.020) for test and control patients, respectively. This difference was not statistically significant (p = 0.069). Conclusions. The superimposition of the 3D surface models revealed an excellent peri-implant soft tissue stability in both groups of patients, with minimal changes registered along time.

6.
Eur J Surg Oncol ; 39(12): 1407-14, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24119717

RESUMEN

AIMS: According to the recent Japanese Gastric Cancer Association's gastric cancer treatment guidelines, bursectomy is recommended for tumors penetrating the serosa of the posterior gastric wall. However, there is still little data to show whether bursectomy improves patient survival. The aim of this study is to evaluate the efficacy of bursectomy for subserosa or serosa-positive gastric cancer in terms of overall survival. METHOD: From April 2001 to December 2006, 470 patients underwent curative resection for macroscopically subserosa or serosa-positive gastric cancer. These patients were grouped according to whether bursectomy was performed or not (bursectomy+/bursectomy-). Clinicopathological characteristics and incidence of complications were compared between the groups. The overall survival rates were analyzed using a Cox proportional hazards model. RESULTS: There was no significant difference in morbidity and mortality between the bursectomy+ and bursectomy- groups. In the multivariable analysis for overall survival, bursectomy was not a significant independent factor (p = 0.978). In the subgroup analysis for clinical and pathological stage III and IV, and tumors penetrating the serosa of the posterior gastric wall, bursectomy did not have significant effect on overall survival as well (p = 0.582, 0.453, and 0.532, respectively). In the propensity score-matched patients, bursectomy still showed no significant effect on overall survival (p = 0.804). CONCLUSIONS: Bursectomy is unlikely to improve overall survival in patients with macroscopically subserosa or serosa-positive gastric cancer.


Asunto(s)
Escisión del Ganglio Linfático , Recurrencia Local de Neoplasia , Cavidad Peritoneal/cirugía , Membrana Serosa/patología , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Gastrectomía , Hospitales de Alto Volumen , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Tempo Operativo , Estudios Retrospectivos , Tasa de Supervivencia
7.
J Nanosci Nanotechnol ; 11(7): 6523-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22121749

RESUMEN

In the nanoimprint lithography (NIL) process, profile control of imprint masters is a very important task. Therefore, we attempted to control the etched slope of imprint masters as a function of adding O2 to CF4 plasma. Etched profile mechanisms and relationships between the etch kinetics and plasma chemistry were explored using zero-dimensional-based modeling. O2 flow rate increased to 24 sccm, the Si etch rate increased in the range of 186-393 nm/min, while the etch rate rapidly decreased as the O2 flow rate increases beyond 24 sccm. Meanwhile, change in the etch rate of SiO2 followed a similar tendency as the etch rate of Si as a function of O2 flow rate in the CF4/O2 mixing gases. The Si and SiO2 etch rate were expected to be closely dependent on the F radical intensity in CF4/O2 mixing gases. Moreover, the results of simulated normalized lateral etch critical dimension (NLECD) are in agreement with the measured NLECD as a function of O2 flow rate in the CF4/O2 mixing gases.

8.
Eur J Vasc Endovasc Surg ; 37(5): 572-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19208448

RESUMEN

OBJECTIVES: To observe the clinical features and angiographic findings in patients with a spontaneous isolated superior mesenteric artery dissection (SISMAD) and to identify any correlation between them. METHODS: From a single institution, 32 patients (22 symptomatic patients at presentation; mean age 54years; men 97%) with SISMAD were retrospectively reviewed. All patients were available for clinical follow-up after treatment (conservative, n=28, 88%, open or endovascular superior mesenteric artery (SMA) reconstruction, n=4, 12%), and follow-up CT scans were available in 28 patients (mean 22months, range 1-80months). RESULTS: We found a positive correlation between pain severity and dissection length (p=0.03, rho=0.50, Spearman's partial correlation analysis). After conservative treatment, only one patient (3%) required bowel resection, and there was no difference in outcome between patients who were treated with anticoagulation or anti-platelet therapy and those who were not (p=1.00, Fisher's exact test). No patients had progression of their lesion on the follow-up CT angiography. CONCLUSIONS: In SISMAD patients, dissection length is positively associated with more severe clinical symptoms. After conservative treatment, we observed a benign clinical course and no CT progression of the dissection, even without anticoagulation or anti-platelet therapy. Based on our observation, patients with SISMAD can be treated conservatively without anticoagulation therapy.


Asunto(s)
Dolor Abdominal/etiología , Angiografía/métodos , Disección Aórtica/diagnóstico por imagen , Arteria Mesentérica Superior , Enfermedades Vasculares/diagnóstico por imagen , Procedimientos Quirúrgicos Vasculares/métodos , Dolor Abdominal/diagnóstico , Dolor Abdominal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Disección Aórtica/complicaciones , Disección Aórtica/cirugía , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Enfermedades Vasculares/complicaciones , Enfermedades Vasculares/cirugía
9.
Eur J Vasc Endovasc Surg ; 35(3): 341-5, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17988904

RESUMEN

PURPOSE: To test the hypothesis that a proximal arterial occlusion has a protective effect on the progression of distal arterial disease, assessed by distal runoff resistance score (DRRS). MATERIALS AND METHODS: One hundred and nineteen patients (median age 64 y, male 96%) with a unilateral iliac and/or femoral arterial occlusion caused by atherosclerosis were analyzed retrospectively. DRRS was assessed on arteriograms of the test limb (with proximal arterial occlusion) and control limb (contralateral limb). Multivariate analysis was performed to determine if a proximal arterial occlusion was an independent risk factor for the development of a difference in the DRRS between the test and control limbs. RESULTS: The clinical features of the subjects were claudication in 85%, ankle brachial index 0.52 (median), diabetes in 30% and smoker in 76%. The upper leg DRRS of the test limb was significantly lower in the iliac occlusion group than in the control limb (1.87+/-1.69 vs 2.85+/-2.75, p=0.032). However, multivariate analysis failed to identify any risk factors associated with the difference in DRRS in both limbs. CONCLUSION: There was no evidence that a proximal arterial occlusion was associated with a slower progression of distal arterial disease.


Asunto(s)
Arteriopatías Oclusivas/fisiopatología , Aterosclerosis/fisiopatología , Arteria Femoral , Arteria Ilíaca , Resistencia Vascular , Anciano , Arteriopatías Oclusivas/epidemiología , Aterosclerosis/complicaciones , Comorbilidad , Progresión de la Enfermedad , Femenino , Arteria Femoral/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Arteria Poplítea/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Estadísticas no Paramétricas , Arterias Tibiales/fisiopatología
10.
J Bone Joint Surg Br ; 89(12): 1645-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18057367

RESUMEN

We describe our experience with the 'four-in-one' procedure for habitual dislocation of the patella in five children (six knees). All the patients presented with severe generalised ligamentous laxity and aplasia of the trochlear groove. All had a lateral release, proximal 'tube' realignment of the patella, semitendinosus tenodesis and transfer of the patellar tendon. The mean age at the time of the operation was 6.1 years (4.9 to 6.9), and the patients were followed up for a mean of 54.5 months (31 to 66). The clinical results were evaluated using the Kujala score. There has been no recurrence of dislocation. All the patients have returned to full activities and the parents and children were satisfied with the clinical results. The mean Kujala score was 95.3 (88 to 98). Two patients had marginal skin necrosis which healed after debridement and secondary closure. These early results in this small group have shown that the 'four-in-one' procedure is effective in the treatment of obligatory dislocation of the patella in children with severe ligamentous laxity and trochlear aplasia.


Asunto(s)
Rótula/cirugía , Luxación de la Rótula/cirugía , Niño , Preescolar , Síndrome de Down/cirugía , Femenino , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Rótula/diagnóstico por imagen , Luxación de la Rótula/diagnóstico por imagen , Satisfacción del Paciente , Radiografía , Recurrencia , Tendones/cirugía , Resultado del Tratamiento
11.
Nucl Med Biol ; 28(6): 719-25, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11518654

RESUMEN

A samarium 153-chitosan complex was prepared by simply mixing acidic solutions of chitosan and (153)SmCl(3). When a solution of this complex was injected into the knee joints of rabbits, minimal extra-articular leakage was observed. This can be attributed to the rapid change in the pH of the complex solution from acidic to neutral, resulting in the formation of gel followed by the subsequent retention in the administered site. Thus, the complex solution represents a promising candidate for radiation synovectomy.


Asunto(s)
Quitina/síntesis química , Articulación de la Rodilla/efectos de la radiación , Radioisótopos/uso terapéutico , Líquido Sinovial/efectos de la radiación , Animales , Quitina/análogos & derivados , Quitina/farmacocinética , Quitina/uso terapéutico , Quitosano , Articulación de la Rodilla/metabolismo , Masculino , Conejos , Radioisótopos/farmacocinética , Distribución Tisular
12.
Perit Dial Int ; 21(3): 245-53, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11475339

RESUMEN

OBJECTIVE: The effect of long-term use of high glucose dialysate on peritoneal structure and function, and its relation with accumulation of advanced glycosylation end-product (AGE) in the peritoneum was investigated in this study. METHODS: Dialysates with 4.25% glucose were injected into the peritoneal cavity of normal rats for 12 weeks without (PD, n = 7) and with (1 g/L, PD+AG, n = 7) aminoguanidine in their drinking water. Rats not having intraperitoneal (IP) injection served as control (n = 9). After 12 weeks of IP injection, a 2-hour peritoneal equilibration test (PET) was performed using 30 mL 4.25% glucose dialysate. Intraperitoneal volume (IPV), dialysate-to-plasma urea ratio at 2 hours (D/P2), the ratio of dialysate glucose at 2 hours to initial dialysate glucose (D2/D0), and the peritoneal fluid absorption rate (Qa) were evaluated. After the PET, samples of the parietal peritoneum were taken for hematoxylin and eosin (H&E) staining and immunohistochemical staining for AGE. RESULTS: The IPV and D2/D0 glucose were significantly lower and Qa and D2/P2 urea significantly higher in the PD group than in the control group. Aminoguanidine reversed in part the changes in IPV and D2/P2 urea in the PD group; it had no effect on Qa and D2/D0 glucose. The H&E staining showed a linear mesothelial lining with negligible cells and capillaries in the narrow submesothelial space in the control group. Mesothelial denudation and submesothelial infiltration of monocytes and capillary formation were observed in the PD group. Mesothelial denudation was relatively intact in the PD+AG group compared with the PD group. Submesothelial monocyte infiltration and capillary formation in the PD+AG group were not as prominent as in the PD group. Positive AGE staining was found in the submesothelial space, vascular walls, and endomysium in the PD group, while it was markedly attenuated in PD+AG group and negligible in the control group. CONCLUSION: Long-term use of high glucose solutions induced peritoneal AGE accumulation and mesothelial denudation, and increased peritoneal permeability and peritoneal fluid absorption rate. Inhibition of peritoneal AGE accumulation prevented those functional and structural damages to the peritoneum.


Asunto(s)
Inhibidores Enzimáticos/efectos adversos , Guanidinas/efectos adversos , Soluciones para Hemodiálisis/efectos adversos , Peritoneo/patología , Peritoneo/fisiopatología , Animales , Masculino , Peritoneo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
13.
J Vasc Interv Radiol ; 12(5): 647-51, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11340148

RESUMEN

The authors assessed the efficacy of an antireflux valve stent in the palliation of malignant esophagogastric junction (EGJ) obstruction after in vitro testing of the stent. Seventeen patients with inoperable malignant EGJ obstruction were treated. Antireflux valves, made of three polyurethane leaflets, were attached to the distal part of the stent to prevent reflux. When the flow rate of normal saline was 100 mL/sec in the forward direction, the valve fully opened at a pressure of 10 mm Hg. When the flow rate of normal saline was 0.35 mL/sec in the backward direction, the valve nearly completely closed at a pressure of 10 mm Hg. Stent placement was successful in all patients without complications. The median dysphagia score decreased significantly, from 3.0 (dysphagia to liquids) to 1.0 (dysphagia to normal solid food) (P < .0005). No patients experienced reflux symptoms. There was one case of stent migration. A valve stent that can prevent major reflux is an effective device for the palliation of malignant EGJ obstruction.


Asunto(s)
Neoplasias Esofágicas/complicaciones , Estenosis Esofágica/terapia , Unión Esofagogástrica , Cuidados Paliativos , Stents , Anciano , Anciano de 80 o más Años , Femenino , Reflujo Gastroesofágico/terapia , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
14.
Radiology ; 219(3): 679-83, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11376254

RESUMEN

PURPOSE: To assess the usefulness of flexible covered metallic stents in the palliation of malignant obstruction of the gastric outlet and duodenum. MATERIALS AND METHODS: Twenty-four consecutive patients with malignant obstruction of the gastric outlet (n = 22) or duodenum (n = 2) underwent palliative treatment with self-expandable flexible covered metallic stents. Fourteen patients had advanced gastric carcinoma at the antrum and/or pylorus, and eight had obstruction at the anastomosis site of previous gastrojejunostomy. Complications and clinical status were investigated during the study period. RESULTS: The technical success rate was 75% (18 of 24 patients). Twenty-one stents were placed in 18 patients by using an introducer 6 (n = 7) or 8 mm (n = 14) in diameter. The mean follow-up period was 3.4 months (range, 1 week to 9 months). Symptoms improved in 12 (67%) patients after the procedure. There was no change in symptoms in five and a decrease in one. Twelve patients died during the follow-up period (mean survival, 4.3 months). The complication rate was 25% (six of 24 patients), including stent migration (n = 5) and fracture (n = 3). CONCLUSION: Flexible covered metallic stent placement can be useful for palliation in patients with malignant obstruction of the gastric outlet or duodenum.


Asunto(s)
Obstrucción Duodenal/etiología , Obstrucción Duodenal/terapia , Obstrucción de la Salida Gástrica/etiología , Obstrucción de la Salida Gástrica/terapia , Cuidados Paliativos/métodos , Stents , Adulto , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Obstrucción Duodenal/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Obstrucción de la Salida Gástrica/diagnóstico por imagen , Humanos , Masculino , Radiografía , Neoplasias Gástricas/complicaciones , Factores de Tiempo
15.
Br J Pharmacol ; 132(3): 623-30, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11159714

RESUMEN

1. Hypersensitivity to the drug sulfamethoxazole (SMX) is thought to be a consequence of bioactivation to the hydroxylamine metabolite (SMX-NHOH) and further oxidation to the ultimate reactive metabolite, nitroso-sulfamethoxazole (SMX-NO). SMX-NO covalently modifies self proteins which in turn might be recognized as neo-antigens by T-cells. The antioxidant glutathione (GSH) is known to protect cells from reactive metabolites by conjugation and subsequent dissociation to SMX-NHOH and/or SMX. 2. To study the reactivity of T-cells to SMX metabolites and their respective role in the generation of drug-specific T-cells, we analysed the effect of GSH on the response of PBMC to SMX and its metabolites SMX-NHOH and SMX-NO. Furthermore, we monitored the proliferative response of drug-specific T-cell clones in the presence or absence of GSH. 3. We found that addition of GSH to peripheral blood mononuclear cells had no effect on the SMX-specific response but enhanced the proliferation to SMX-metabolites. The response of SMX-NO-specific T-cell clones was abrogated when GSH was present during the covalent haptenation of antigen presenting cells (APC). Conversely, SMX-specific T-cell clones gained reactivity through the conversion of SMX-NO to the parent drug by GSH. While GSH had no effect on the initial activation of T-cell clones, it prevented covalent binding to APCs, reduced toxicity and thereby led to proliferation of drug-specific T-cells to non-reactive drug metabolites. 4. Our data support the concept that in allergic individuals T-cells recognize the non-covalently bound parent drug rather than APC covalently modified by SMX-NO.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Glutatión/farmacología , Activación de Linfocitos/efectos de los fármacos , Sulfametoxazol/análogos & derivados , Sulfametoxazol/farmacología , Adulto , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Linfocitos T CD4-Positivos/citología , División Celular/efectos de los fármacos , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Hipersensibilidad a las Drogas , Interacciones Farmacológicas , Femenino , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/metabolismo , Sulfametoxazol/metabolismo
16.
Abdom Imaging ; 26(1): 48-54, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11116360

RESUMEN

BACKGROUND: We wanted to establish reasonable cholangiographic diagnostic criteria by determining the sensitivity of cholangiography in detecting choledochoceles and those factors that could compromise visualization of choledochoceles. METHODS: Over 4 years, 21 patients (seven male, 14 female; mean age = 67 years) were confirmed as having choledochoceles on endoscopic retrograde cholangiopancreatography (ERCP). Cholangiographic diagnosis was made by following three criteria: a radiolucent halo around the distal common bile duct (CBD), bulbous dilatation of the distal CBD, and the presence of sequential morphologic changes on serial cholangiography. Any two or more combinations of these three criteria were considered enough to diagnose a choledochocele on cholangiography. We compared cholangiographic imaging findings with the ERCP results. RESULTS: Of 21 patients with choledochoceles, nine (43%) were correctly diagnosed on cholangiography. A radiolucent halo was present in six (28%) patients; four of these cases showed optimal duodenal filling, one showed faint duodenal filling, and one showed poor duodenal filling. The shapes of the distal CBD were bulbous, conelike, and blunt. Morphologic changes such as collapsing and bulging of the choledochocele could be seen in 12 (57%) patients on serial cholangiography. Waists were seen in 11 (52%), pseudowebs in four (19%), and wrinkling of the distal CBD in seven (33%). CONCLUSION: Cholangiography should be obtained with optimal timing and adequate conditions to diagnose choledochocele correctly.


Asunto(s)
Colangiografía , Quiste del Colédoco/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
17.
Nucl Med Commun ; 21(10): 959-64, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11130338

RESUMEN

The purpose of this study was to estimate the absorbed dose distribution of Ho-166 endovascular beta irradiation using an angio-catheter. The liquid form of Ho-166 was produced at the Korea Atomic Energy Research Institute (KAERI) by an (n,gamma) reaction. Ho-166 has a half-life of 26.8 h and emits a high-energy beta particle with a maximum energy of 1.85 MeV. GafChromic film was used for the estimation of the absorbed dose of beta particles. A Co-60 teletherapy source and a 6 MV photon beam from a linear accelerator were used to generate dose-optical density calibration curves. The exposed films were read using a videodensitometer. With a modified micrometer, the film was positioned accurately on the surface of the balloon in water. The balloon was filled with Ho-166 solution to a pressure of 4 atm. Several film exposures were made with varying irradiation times and activities. The radiation absorbed dose rates were 1.02, 0.51 and 0.35 Gy x min(-1) x GBq(-1) x ml(-1) at the balloon surface, 0.5 and 1 mm from the balloon surface, respectively. The absorbed dose distribution revealed that Ho-166 is a good source for endovascular irradiation as the beta range is very short, avoiding unnecessary irradiation of normal tissue. A clinically applicable irradiation and duration of exposure were achievable utilizing our system.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Braquiterapia/métodos , Holmio/uso terapéutico , Radioisótopos/uso terapéutico , Radiofármacos/uso terapéutico , Enfermedad Coronaria/radioterapia , Enfermedad Coronaria/terapia , Humanos , Fantasmas de Imagen , Dosificación Radioterapéutica
18.
J Nucl Cardiol ; 7(5): 478-83, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11083197

RESUMEN

BACKGROUND: Neointimal formation in response to arterial injury is a major contributing element in restenosis after coronary balloon angioplasty and stenting. Endovascular irradiation has been reported to be effective in reducing restenosis. The purpose of this study was to investigate the effect of beta-emitting holmium-166 for the inhibition of neointimal formation in porcine coronary artery. METHODS AND RESULTS: A total of 34 pigs weighing 25 to 30 kg underwent oversized balloon injury (balloon/artery ratio, 1.3:1.4) at the proximal portion of the left anterior descending and circumflex arteries. One artery was randomly assigned to receive radiation after injury. Ho-166 was left in the balloon within the delivery catheter for a period sufficient to deliver 9 Gy and 18 Gy to a depth of 1 mm from the surface of the balloon. Four weeks later, pigs were sacrificed and hearts were perfusion-fixed, followed by histopathologic analysis and planimetry for measurement of maximal intimal thickness, intimal area, and fracture length. The coronary segment of the pigs in the control group had neointimal area of 1.18+/-0.55 mm2; the pigs in the 9-Gy group had neointimal area of 0.68+/-0.40 mm2 (P<.05 vs. control); and the pigs in the 18-Gy group had neointimal area of 0.29+/-0.12 mm2 (P<.01 vs. control). The maximal intimal thickness in the 18-Gy group (0.14+/-0.11 mm) was significantly reduced compared with the maximal intimal thickness in the control group (0.48+/-0.13 mm) (P<.01). CONCLUSIONS: Intracoronary radiation with liquid Ho-166 contained in a perfusion balloon catheter is feasible and effective in reducing neointimal formation after coronary overstretch injury in pigs. Therefore intracoronary irradiation on the injured segment may further reduce restenosis after balloon injury.


Asunto(s)
Cateterismo , Vasos Coronarios/patología , Holmio/uso terapéutico , Radioisótopos/uso terapéutico , Túnica Íntima/patología , Animales , Arterias/patología , Arterias/efectos de la radiación , Cateterismo Cardíaco , Enfermedad Coronaria/patología , Enfermedad Coronaria/radioterapia , Vasos Coronarios/lesiones , Vasos Coronarios/efectos de la radiación , Holmio/administración & dosificación , Radioisótopos/administración & dosificación , Dosificación Radioterapéutica , Recurrencia , Porcinos , Túnica Íntima/efectos de la radiación
19.
Abdom Imaging ; 25(5): 483-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10931981

RESUMEN

BACKGROUND: We evaluated the differences in sample adequacy and safety between a transseptal needle and Quick-core biopsy needle for transjugular liver biopsy. METHODS: Eighteen consecutive patients who had a bleeding diatheses and/or ascites underwent transjugular liver biopsy using a transseptal needle (11 patients) and Quick-core biopsy needle (seven patients). The length of the specimens was measured before fixation. A pathologist reviewed histologic slides for sample adequacy and pathologic diagnoses. Clinical records were reviewed for complication. RESULTS: In all patients, liver biopsy was successful. A total of 45 specimens were obtained, with an average of 2.5 passes per patient. The length of specimen was significantly longer with the Quick-core biopsy needle than with the transseptal needle (p<0.05). Biopsied tissue was fragmented in 17 of 25 specimens with the transseptal needle but not fragmented in any specimen with the Quick-core biopsy needle. All specimens were determined to be adequate except one with the transseptal needle. There was no early or delayed complication in any patient. CONCLUSION: Transjugular liver biopsy is a safe and effective procedure without any significant difference in complication and adequacy when using a transseptal needle or Quick-core biopsy needle. Larger specimens can be obtained without tissue fragmentation with the Quick-core biopsy needle.


Asunto(s)
Biopsia con Aguja/métodos , Cateterismo Periférico , Hepatopatías/patología , Agujas , Adolescente , Adulto , Anciano , Diseño de Equipo , Femenino , Humanos , Venas Yugulares , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
20.
Eur J Nucl Med ; 27(7): 842-6, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10952496

RESUMEN

Bowen's disease can be treated by various methods, including surgical excision, cryosurgery, laser ablation, curettage, Mohs' microsurgery and ionizing radiation. Radiotherapy has been a useful therapeutic modality in the treatment of Bowen's disease and other skin cancers in areas which are difficult to excise, especially the central areas of the face, including eyelids, nose and lips. To overcome some of the disadvantages of external radiotherapy, a specially designed skin patch coated with high-energy beta-emitter holmium-166 was made for topical application at our institute. Twenty-nine sites of Bowen's disease in eight patients, confirmed by skin biopsy, were treated with 166Ho patches. The patches were applied to the surface of skin cancers for 30-60 min for a total radiation dose of 35 Gy (3500 rads). One to two weeks after application of the 166Ho patch, desquamation, erythema or erosion developed in treated sites, but these acute radiation reactions healed gradually with epithelial regeneration, and they showed good functional and cosmetic results without any complications. Follow-up biopsies were performed 1-5 months after 166Ho patch therapy, and they did not show any signs of Bowen's disease. One to two years after treatment with 166Ho skin patches, there were no recurrences of Bowen's diseases and no late complications. The 166Ho patch is an effective and convenient alternative method for the treatment of Bowen's disease that yields good cosmetic and functional results.


Asunto(s)
Enfermedad de Bowen/radioterapia , Braquiterapia/métodos , Holmio/uso terapéutico , Radioisótopos/uso terapéutico , Neoplasias Cutáneas/radioterapia , Anciano , Femenino , Holmio/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Radioisótopos/administración & dosificación , Dosificación Radioterapéutica , Factores de Tiempo
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