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1.
Int J Oral Maxillofac Surg ; 52(5): 515-523, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36123273

RESUMEN

The aim of this study was to clarify the correlation between imaging findings obtained using intraoral ultrasonography (US) and pathological findings of tongue cancers, and to examine the predictive value of intraoral US findings with respect to occult nodal metastasis. This was a retrospective study based on the medical records of 123 patients with T1-2N0 tongue cancer. The depth of invasion (DOI) on intraoral US was positively correlated with the pathological invasion depth (PID) (ρ = 0.7080, P < 0.0001). Receiver operating characteristic analyses revealed an optimal DOI cut-off value of 4.1 mm and optimal PID cut-off value of 3.9 mm to detect nodal metastasis. Regarding the margin shape of the primary tumour on intraoral US, the incidence of nodal metastasis was significantly higher for the permeated type than for the pressure type (P < 0.001) and wedge-shaped type (P = 0.002). Furthermore, tumours with peritumoural vascularity assessed by power Doppler US had a significantly higher incidence of nodal metastasis than tumours without (P = 0.003). The sensitivity, specificity, and accuracy of the permeated type to predict nodal metastasis was 53.6%, 95.8%, and 86.2%, respectively. These results suggest that intraoral US findings closely reflect pathological findings and could be useful to predict occult nodal metastasis in patients with early-stage tongue cancer.


Asunto(s)
Neoplasias de la Lengua , Humanos , Neoplasias de la Lengua/diagnóstico por imagen , Estudios Retrospectivos , Lengua , Angiografía , Factor de Crecimiento Transformador beta , Ultrasonografía
2.
Spinal Cord ; 50(1): 51-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21876552

RESUMEN

STUDY DESIGN: A retrospective multicenter study. OBJECTIVES: To investigate the characteristics of bowel dysfunction in elderly people with traumatic central cord syndrome (TCCS). SETTING: A total of 28 Rosai hospitals in Japan. METHODS: The Rosai Hospital registry included 3006 persons with spinal cord injury during 1997-2007. The study subjects were 186 patients with TCCS (160 men, 26 women; mean age, 61.7±11.6 years, ±s.d.). Patients were divided according to age into the young group (<50 years, n=30), the middle-age group (50-69 years, n=112) and the elderly group (≥70 years, n=44). We assessed the differences in bowel management techniques (spontaneous, rectal medications and manual emptying) and activity of daily living (ADL) with respect to bowel care at discharge among the three groups. RESULTS: Continent spontaneous defecation was the most common bowel management method (50%, 93/186). The percentage of elderly subjects on continent spontaneous defecation (36.4%) was significantly less than that of the young group (66.7%; P<0.05). Furthermore, the percentage of elderly patients who required no bowel care (18.2%) was significantly less than those of the young (53.3%) and middle-age groups (41.1%; P<0.01). However, few differences in bowel care-related ADL were recognized among the three groups in patients who required manual emptying. CONCLUSION: The results identified significantly fewer patients aged ≥70 years with 'continent spontaneous defecation' or 'independent for bowel care' compared with younger patients. The results also highlighted the clinical importance of bowel dysfunction associated with TCCS especially in elderly people.


Asunto(s)
Actividades Cotidianas , Envejecimiento/fisiología , Intestino Neurogénico/fisiopatología , Intestino Neurogénico/rehabilitación , Traumatismos de la Médula Espinal/fisiopatología , Adulto , Anciano , Defecación/fisiología , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Intestino Neurogénico/etiología , Modalidades de Fisioterapia/tendencias , Sistema de Registros , Estudios Retrospectivos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/patología , Resultado del Tratamiento
3.
Int J Oral Maxillofac Surg ; 41(3): 290-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22113115

RESUMEN

The purpose of this study was to determine how keratocystic odontogenic tumours (KCOTs) in the mandible are reduced during marsupialisation, and to predict the best time for secondary enucleation by analysing computed tomography (CT) images. 15 patients with KCOTs were treated with marsupialisation surgery, and 42 series of CT data taken during the marsupialisation process were analysed. CT data were reconstructed in three-dimensional (3D) images. The 3D images were used to measure the diameter and volume, and to analyse the changes that occurred after marsupialisation. Marsupialised KCOTs tended to be reduced equally towards the window in the tumour. The amount of volume reduction per day (V(r)) was reduced in proportion to the volume (V) with the formula V(r)=-0.0029×V. The formula manipulation for V was V=V(0)×e(-0.0029t) (t=duration after marsupialisaton (day)). The volume of marsupialised KCOTs was reduced by half over a 239 day cycle. These results demonstrate that the future shape of marsupialised mandibular KCOTs, under good control, could be predicted with significant accuracy using CT data. This prediction could decrease the prolonged marsupialisation state in patients with KCOTs.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Neoplasias Mandibulares/cirugía , Tumores Odontogénicos/cirugía , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Algoritmos , Legrado , Desbridamiento , Descompresión Quirúrgica , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Neoplasias Mandibulares/diagnóstico por imagen , Persona de Mediana Edad , Tumores Odontogénicos/diagnóstico por imagen , Osteogénesis/fisiología , Factores de Tiempo , Cicatrización de Heridas/fisiología , Adulto Joven
4.
Clin Nephrol ; 75(2): 158-64, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21255546

RESUMEN

We report the case of a 31-year-old male with enlarged kidneys and glomerulocystic kidney disease (GCKD). The patient had no family history of renal disease or other diseases. On initial presentation he complained of poor eyesight, and hypertensive retinopathy and elevated serum creatinine (5.0 mg/dl) were found at that time. Renal biopsy showed cystic dilatation of Bowman's capsule and atrophy of the glomerular tuft. Thus, an adult case of sporadic GCKD was diagnosed. Based on previous reports, kidney size in patients with adult type GCKD varies from small to large. Our patient's kidneys are the largest ever reported (right kidney was 22 cm×10 cm, left kidney was 19 cm×10 cm). A review of the literature dealing with sporadic adult GCKD suggested that it is difficult to diagnose this disease early in its course.


Asunto(s)
Enfermedades Renales Quísticas/diagnóstico , Riñón/patología , Adulto , Biopsia , Cápsula Glomerular/patología , Humanos , Riñón/diagnóstico por imagen , Enfermedades Renales Quísticas/terapia , Glomérulos Renales/patología , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos , Valor Predictivo de las Pruebas , Diálisis Renal , Tomografía Computarizada por Rayos X , Ultrasonografía
5.
Int J Oral Maxillofac Surg ; 35(5): 416-20, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16376052

RESUMEN

Twenty-seven patients with oral malignant tumours, who underwent neck dissection with preservation of the internal jugular vein (IJV), were studied retrospectively to evaluate patency of the IJV. Twenty-three patients underwent ablative surgery of the primary lesion with neck dissection and 4 underwent neck dissection alone. Three patients received simple closure and skin grafting of the primary lesion, and 20 received reconstruction surgery (4 platysma flaps, 3 radial forearm flaps, 3 lateral upper arm flaps, 2 pectoralis major myocutaneous flaps and 8 rectus abdominis myocutaneous flaps). The maximum and minimum diameters of the IJV as measured on computed tomographic (CT) scans were used to assess patency. The cross-sectional area of the IJV and the ratio of its long axis to short axis (L/S ratio) were calculated. The relation between the change in IJV status and the type of flap used for reconstruction was also examined. Occlusion of the IJV was present in 3.7% of the patients, and 'narrowing' was present in 63.6%. The size of the flap significantly correlated with 'narrowing' of the IJV, suggesting that 'narrowing' was caused mainly by compression due to the flap.


Asunto(s)
Venas Yugulares/lesiones , Disección del Cuello/efectos adversos , Procedimientos de Cirugía Plástica/efectos adversos , Colgajos Quirúrgicos/efectos adversos , Grado de Desobstrucción Vascular , Carcinoma de Células Escamosas/cirugía , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/etiología , Humanos , Venas Yugulares/diagnóstico por imagen , Venas Yugulares/patología , Metástasis Linfática , Microcirugia/efectos adversos , Neoplasias de la Boca/cirugía , Disección del Cuello/métodos , Radiografía , Estudios Retrospectivos
6.
Dentomaxillofac Radiol ; 34(6): 350-2, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16227477

RESUMEN

OBJECTIVES: To correlate diagnostic accuracy for proximal caries with perceptibility of low contrast image details using regression analysis. The other purpose was to determine the attenuation range required for proximal caries diagnosis. METHODS: The results of the two types of observer performance tests described above were retrieved from previous studies. Recording media included in those studies were the Compuray and the Dixel, direct digital radiographic systems, and Ektaspeed Plus film. The average numbers of perceptibility of image details from five observers were calculated for each step and for every combination of contiguous steps of the aluminium test phantom from the perceptibility test. The average diagnostic accuracy for proximal caries from the same five observers was correlated with the total number of perceptible details from the phantom using regression analysis. Finally, attenuation range required for proximal caries diagnosis was calculated from the attenuation range of the phantom where the maximum correlation coefficient was obtained. RESULTS: Maximum correlation (r=0.68) was obtained at the combination of five contiguous steps of the aluminium test phantom. Attenuation range required for proximal caries diagnosis corresponded to the 2 mm to 6 mm thickness of aluminium with acrylic block of 12 mm thickness. CONCLUSIONS: There is a correlation between perceptibility of low contrast image details and diagnostic accuracy for proximal caries. There may be a possibility to simplify observer performance tests for proximal caries diagnosis by using the standardized phantom simulating its attenuation range.


Asunto(s)
Caries Dental/diagnóstico por imagen , Adolescente , Análisis de Varianza , Humanos , Tercer Molar/diagnóstico por imagen , Curva ROC , Radiografía Dental Digital , Análisis de Regresión , Película para Rayos X
7.
Dentomaxillofac Radiol ; 34(3): 140-4, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15897283

RESUMEN

OBJECTIVE: To elucidate the effect of automatic exposure compensation (AEC) on the diagnostic accuracy of proximal caries by comparing several digital intraoral imaging systems with a film. MATERIALS AND METHODS: Twenty-seven extracted teeth served as proximal caries samples. Three digital radiographic systems; the Compuray, the Dixel, and the Sens-A-Ray without scintillator layer, and Kodak Ekta-speed Plus films were used as recording media. Radiographs of the teeth samples were obtained with each recording medium under seven to eight different exposures including the optimum level. Six oral radiologists evaluated the possibility of proximal caries with the five-grade-confidence-scale. On digital radiographs, image manipulations were allowed after the initial assessment. Receiver operating characteristic (ROC) curves were obtained at each exposure in each recording medium. The area under the ROC curve (Az) was used as the representative value of diagnostic accuracy. Diagnostic accuracy (DA) curves were obtained by plotting averaged Az values from all observers as a function of incident exposure in each system. RESULTS: The effect of exposure variation on the DA was slight in the film while it was significantly larger in the digital systems without AEC. Among digital systems, the effect of exposure variation was smaller in the system with AEC than those without AEC. There was no significant effect on the diagnostic accuracy even if digital image manipulation was employed. CONCLUSION: AEC minimizes the decrease of DA due to inadequate exposures. Since it compensates for the narrow exposure range in the digital intraoral sensor systems, the system with AEC may be preferable for the clinical diagnostic tasks.


Asunto(s)
Caries Dental/diagnóstico por imagen , Esmalte Dental/diagnóstico por imagen , Radiografía Dental Digital/métodos , Adolescente , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Variaciones Dependientes del Observador , Curva ROC , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Radiografía Dental Digital/estadística & datos numéricos , Factores de Tiempo , Película para Rayos X
8.
Dentomaxillofac Radiol ; 32(3): 191-7, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12917286

RESUMEN

OBJECTIVES: To construct perceptibility curves (PCs) for given calibration settings in order to define psychophysical properties of the Digora storage phosphor system and to evaluate the effects of automatic exposure correction (AEC) on the PCs. METHODS: The Digora system was calibrated at two exposures, 80 microC kg(-1) (high calibration) and 40 microC kg(-1) (low calibration). Since the grey levels displayed in the radiographs are adjusted by AEC, dose-response functions at high calibration were obtained using AEC on and off modes. The dose-response function at low calibration was obtained with AEC off. The PC at each experimental setting was calculated using known physical parameters of the system and the performance of the average observer used in a previous study. In addition, PCs were also constructed using transmitted radiation flux behind the test object calculated from the attenuation coefficient in order to study observer and system performance. PCs obtained under these conditions were compared. RESULTS: The PC using calculated transmitted radiation flux behind the test object showed a wide plateau at the peak owing to AEC, while the PC obtained by a modified approach showed a higher but narrower peak. There were no differences between the two PCs using AEC on and off modes when the PCs were constructed using a modified approach. There were no differences between the two PCs obtained at high and low calibration settings or between the three PCs obtained with AEC on except for the position along the exposure axis. CONCLUSIONS: Psychophysical properties of the Digora system may be determined if we employ registered exposures from a dose-response function with AEC off under a given calibration setting. Under these circumstances the shape and height of the PCs will be unchanged irrespective of the AEC mode.


Asunto(s)
Intensificación de Imagen Radiográfica , Radiografía Dental Digital , Algoritmos , Calibración , Predicción , Humanos , Modelos Lineales , Distribución de Poisson , Psicofísica , Dosis de Radiación , Radiografía Dental Digital/estadística & datos numéricos , Percepción Visual
9.
Biotechniques ; 34(5): 988-90, 992-3, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12765026

RESUMEN

Rapid extraction of total RNA from Eucalyptus leaves is difficult due to the high content of polyphenolics and polysaccharides. A rapid and simple method was developed by using an extraction buffer containing sodium isoascorbate at a concentration of 500 mM. This method consisted of one or two chloroform extractions, one acid guanidium-phenol-chloroform extraction, and isopropanol precipitation alone. The yields of the RNA fractions were 246-1750 micrograms/g fresh weight when leaves of Eucalyptus, five other woody plants, and four herbaceous plants were used as samples. The contamination of the RNA fractions by proteins and polysaccharides was very limited as judged spectrophotometrically. When the RNA fractions were subjected to agarose gel electrophoresis, intact rRNA bands were detected. The RNA fractions could be used for RT-PCR. These results indicate that our new method achieves a simple and rapid preparation of high-quality RNA from leaves of Eucalyptus and other plant species.


Asunto(s)
Ácido Ascórbico/genética , Eucalyptus/química , Eucalyptus/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , ARN/aislamiento & purificación , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/fisiología , Eucalyptus/genética , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/clasificación , Hojas de la Planta/genética , Plantas Modificadas Genéticamente/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Especificidad de la Especie
10.
Dentomaxillofac Radiol ; 30(4): 219-25, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11681484

RESUMEN

OBJECTIVES: To construct Perceptibility Curves (PCs) for contrast-enhanced digital intraoral radiographs. METHODS: Radiographs of a test object having holes of increasing depths were exposed using three digital systems, the CDR (Schick Technologies, Long Island, NY, USA), the Dixel (J Morita MFG, Kyoto, Japan) and the Sens-A-Ray (Regam Medical Systems, Sundsvall, Sweden). The radiographs were contrast-enhanced and PCs constructed in the conventional way using 10 observers. Predicted PCs were calculated and compared with observer data. RESULTS: The PCs showed that contrast enhancement is effective for the perception of small contrast details, especially in the low exposure range. Predicted PCs demonstrated excellent agreement with observer data. CONCLUSIONS: Contrast enhancement should be advantageous in digital radiography. The effects of contrast enhancement on PCs may be predicted without previous knowledge of observer performance.


Asunto(s)
Medios de Contraste , Intensificación de Imagen Radiográfica/métodos , Radiografía Dental Digital , Algoritmos , Predicción , Humanos , Modelos Lineales , Variaciones Dependientes del Observador , Fantasmas de Imagen , Radiografía Dental Digital/instrumentación , Radiografía Dental Digital/métodos , Estadística como Asunto , Propiedades de Superficie , Percepción Visual
11.
Acta Radiol ; 42(1): 88-95, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11167339

RESUMEN

PURPOSE: To evaluate the usefulness of the combination of the two non-invasive modalities US and MR imaging to diagnose masses in the parotid region. MATERIAL AND METHODS: The US and MR findings of 21 patients with parotid masses were analyzed retrospectively by two radiologists without any clinical or histopathological information. The specific points evaluated were location, shape, margin, internal architecture, and intensity level on both US and MR, posterior echo enhancement on US, and capsule-like lining of the tumor on MR. RESULTS: The findings concerning the shape and margin on US and MR were in fairly good agreement. Concerning the findings of the internal architecture, US could reveal the minute structures of the tumor while MR demonstrated differences in the signal intensities of histological tissue types of the various tumors. The posterior echo enhancement on US and the capsule-like lining on MR of the tumors were also useful for the diagnosis. CONCLUSION: Our results suggest that the combination of US and MR is useful for examining soft tissue masses in the parotid region to make a more accurate diagnosis, and not just differentiate malignant lesions from those which are benign.


Asunto(s)
Imagen por Resonancia Magnética , Glándula Parótida/diagnóstico por imagen , Neoplasias de la Parótida/diagnóstico , Adolescente , Adulto , Anciano , Biopsia con Aguja , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Glándula Parótida/patología , Estudios Retrospectivos , Ultrasonografía
12.
Dentomaxillofac Radiol ; 29(4): 238-44, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10918457

RESUMEN

OBJECTIVES: To define criteria for CT and US in differentiating cervical lymph node metastases in oral squamous cell carcinoma (SCC). MATERIALS AND METHODS: CT and/or US of 230 metastatic lymph nodes and 228 benign lymph nodes in 147 patients with oral SCC were retrospectively evaluated. The CT and US findings of each lymph node were compared with the histopathological findings. A metastasis was defined on CT as a lymph node with rim or heterogeneous enhancement, or measuring 10 mm or more in the short axis, regardless of enhancement pattern, and on US as having definite internal echoes, regardless of size, or without definite internal or hilar echoes, but measuring 10 mm or more in the short axis. A lymph node with hilar echoes or a ratio of the long to short axis (L/S ratio) of 3.5 or more was considered benign. A lymph node failing to comform to any of these categories was termed questionable. RESULTS: The positive predictive value (PPV) for CT was 90.8% and the negative predictive value (NPV) was 70.4%. However, 65.7% of all lymph nodes could not be classified as either metastastic or benign. PPV for US was 96.5% and NPV was 88.1%. 25.5% of all lymph nodes could not be classified as either metastatic or benign. CONCLUSIONS: Despite limitations in detecting metastases, by including a third category 'questionable' our criteria appear clinically more useful than other current methods based on two groups only.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Metástasis Linfática/diagnóstico por imagen , Neoplasias de la Boca/patología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Medios de Contraste , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Persona de Mediana Edad , Cuello , Valor Predictivo de las Pruebas , Intensificación de Imagen Radiográfica , Estudios Retrospectivos , Estadísticas no Paramétricas , Ultrasonografía
13.
AJNR Am J Neuroradiol ; 21(6): 1127-32, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10871027

RESUMEN

BACKGROUND AND PURPOSE: Because the presence of cervical metastasis is one of the factors influencing the outcome of patients with carcinoma of the head and neck, its early detection is potentially very important. The purpose of this study was to evaluate the characteristic changes of cervical metastasis revealed by sonography during follow-up and to assess an adequate interval for follow-up sonography of the neck among patients with tongue cancer. METHODS: Forty-three of 44 consecutive patients with squamous cell carcinoma of the tongue, who had undergone interstitial brachytherapy, were examined with sonography of the neck during the posttherapeutic follow-up period. RESULTS: Seventeen cervical lymph node metastases were found in 12 of 43 patients during follow-up. Of these 17 cervical metastases, 16 (94.1%) were accurately diagnosed and one (5.9%) was misdiagnosed as nonmetastatic based on sonographic findings. Sonography of the neck performed in seven patients at an interval of less than 1 month since the last follow-up imaging showed 9 (90.0%) of 10 metastases increased by up to 2 mm in short-axis diameter. Five patients who were followed up at an interval of more than 1 month since the last follow-up imaging had seven metastases increase by 3 to 8 mm in short-axis diameter or a change of echogenicity in the internal structure of lymph nodes or both. Pathologic examinations showed extranodal spread in 3 (42.9%) of these 7 metastases. CONCLUSION: Changes both in size and internal echogenicity can occur as quickly as 2 to 4 weeks between sonographic examinations. Therefore, in high-risk patients, or in those with suspicious sonographic findings, short-interval follow-up sonographic examinations are recommended at least during the first posttherapeutic year. Our findings suggest that follow-up sonography of the neck should be performed monthly, at least during the first posttherapeutic year.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Metástasis Linfática/diagnóstico por imagen , Neoplasias de la Lengua/patología , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/radioterapia , Errores Diagnósticos , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Cuello , Factores de Tiempo , Neoplasias de la Lengua/radioterapia , Ultrasonografía
14.
Artículo en Inglés | MEDLINE | ID: mdl-10760736

RESUMEN

OBJECTIVES: This article demonstrates a new method of making a spacer that increases the distance between the mandible and implanted radioactive sources in interstitial brachytherapy for patients with mobile tongue cancer. STUDY DESIGN: Fifty-three patients with mobile tongue cancer underwent interstitial brachytherapy with spacers made by this new technique. RESULTS: Our spacer is not difficult to create or to use. The spacer was made from a plastic splint by using thermoforming techniques and quick self-curing resin, which did not need waxing, wiring, or casting. The surface of the spacer, which comes in contact with the tongue, is smooth because it is covered with tissue-conditioning material. There were no complaints of pain from the patients. Osteoradionecrosis of the mandible developed in only 1 (1.9%) of these patients. CONCLUSIONS: This spacer is simple to make and prevented osteoradionecrosis.


Asunto(s)
Braquiterapia/instrumentación , Carcinoma de Células Escamosas/radioterapia , Neoplasias de la Lengua/radioterapia , Braquiterapia/efectos adversos , Braquiterapia/métodos , Radioisótopos de Cesio/uso terapéutico , Diseño de Equipo , Humanos , Osteorradionecrosis/epidemiología , Dosificación Radioterapéutica , Radio (Elemento)/uso terapéutico , Resinas Sintéticas , Férulas (Fijadores)
15.
Rheumatology (Oxford) ; 39(2): 165-71, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10725066

RESUMEN

OBJECTIVES: To evaluate the efficacy of filtration leucocytapheresis (LCP) for rheumatoid arthritis (RA). METHODS: LCP was carried out three times, with 1 week separating each session, in 25 drug-resistant RA patients. RESULTS: During each session, 96, 98, 61, 84 and 8% of the granulocytes, monocytes, lymphocytes, platelets and erythrocytes, respectively, that entered the LCP filter were removed. The number of granulocytes, monocytes and lymphocytes in the peripheral blood significantly decreased during each session of LCP. However, there was no significant decrease in the number of circulating blood cells during the study period. On average, 110 x 10(8) granulocytes, 5.23 x 10(8) monocytes, and 20.5 x 10(8) lymphocytes were removed during LCP therapy. Assessment of RA before and after LCP showed a substantial and rapid improvement in the tender joints counts, swollen joint counts, and patient's and physician's assessments. No adverse reactions or complications were noted. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels decreased following LCP, although the change in the latter parameter was statistically insignificant. The concentrations of serum albumin, gamma-globulin, IgG, IgM, CH50 and rheumatoid factor titres did not change during or after LCP. Careful analysis indicated that 16 of 25 patients with RA showed > or =20% improvement following LCP therapy. CONCLUSIONS: Our results suggest that filtration LCP to remove leucocytes from the peripheral blood exerts an immunomodulatory effect in patients with RA.


Asunto(s)
Artritis Reumatoide/terapia , Leucaféresis , Artritis Reumatoide/sangre , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Femenino , Humanos , Articulaciones/patología , Leucaféresis/instrumentación , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Dolor , Resultado del Tratamiento
17.
Curr Genet ; 36(4): 232-40, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10541861

RESUMEN

Uniparental inheritance of the chloroplast genome has been observed in a wide variety of green plants. In Chlamydomonas this phenomenon, which can be selectively inhibited by UV irradiation of mt(+) gametes, has been shown cytologically to be due to the preferential degradation of mt(-)-derived chloroplast nucleoids in young zygotes. The zygote-specific pair of zys1 genes, zys1A and zys1B, is expressed earliest among five genes isolated from a "10-min" zygote library. We report here that the ZYS1 protein, which is encoded by the invertedly duplicated zys1 gene, accumulates in zygotes and is localized in nuclei. In addition, when mt(+) gametes (but not mt(-) gametes) are UV-irradiated before mating, only very limited accumulation of ZYS1 protein can be detected in the resulting zygotes.


Asunto(s)
Proteínas Algáceas , Chlamydomonas reinhardtii/genética , Proteínas de Plantas/genética , Rayos Ultravioleta , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Chlamydomonas reinhardtii/metabolismo , Chlamydomonas reinhardtii/efectos de la radiación , Cloroplastos/genética , Microscopía Fluorescente , Datos de Secuencia Molecular , Proteínas de Plantas/biosíntesis , Alineación de Secuencia , Cigoto/metabolismo , Cigoto/efectos de la radiación
18.
Artículo en Inglés | MEDLINE | ID: mdl-10519762

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the ability of contrast-enhanced magnetic resonance imaging to differentiate hemangioma from lymphangioma in the oral and maxillofacial region. STUDY DESIGN: Contrast-enhanced magnetic resonance imaging was performed in 20 patients (21 masses: 17 hemangiomas and 4 lymphangiomas) through use of either a 0.2-T permanent system or a 0. 5-T superconductive system and spin-echo pulse sequences. RESULTS: After intravenous administration of contrast medium, enhancement was observed in all hemangiomas in areas corresponding to those with high signal on T(2)-weighted images. Unequivocally increased signal was observed in 10 masses, and slightly increased signal was observed in 7 masses. On the other hand, none of the lymphangiomas showed an enhancing mass on contrast-enhanced T(1)-weighted images. CONCLUSIONS: Although contrast-enhanced T(1)-weighted imaging may not improve delineation of masses in all cases, it can be used to differentiate between deep hemangiomas and lymphangiomas.


Asunto(s)
Medios de Contraste , Neoplasias Faciales/diagnóstico , Gadolinio DTPA , Hemangioma/diagnóstico , Neoplasias Maxilomandibulares/diagnóstico , Linfangioma/diagnóstico , Imagen por Resonancia Magnética/métodos , Neoplasias de la Boca/diagnóstico , Adolescente , Adulto , Niño , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Retrospectivos
19.
Dentomaxillofac Radiol ; 28(5): 277-83, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10490745

RESUMEN

OBJECTIVES: To determine technical properties of a direct digital intra-oral radiographic system, the Dixel(R) (J Morita Corporation, Kyoto, Japan). METHODS: A dose response function and the dark current were calculated from two series of exposures to a homogeneous radiation field. The line spread function (LSF) and the modulation transfer function (MTF) were determined from radiographs of an edge. The noise power spectrum (NPS) was determined at three exposures from radiographs exposed to homogeneous radiation fields. Noise equivalent quanta (NEQ) were calculated from the one-dimensional NPS and the MTF. The detective quantum efficiency (DQE) was determined from the NEQ and a representative value of the photon fluence. Signal-to-noise ratios (SNR) were calculated from the NEQs and different signal contrasts. RESULTS: The dose response function demonstrated a slight curvature. There was no effect of the dark current. NPS ranged from 10-5 - 10-7 mm2 depending on exposure and frequency. At a peak of about 2 cycles/mm the DQE is on an average about 30 per cent. SNRs are favorable. CONCLUSION: The technical properties found in this study indicate that the Dixel(R) system is suitable for intra-oral dental radiography.


Asunto(s)
Radiografía Dental Digital/instrumentación , Tecnología Radiológica/instrumentación , Artefactos , Relación Dosis-Respuesta en la Radiación , Humanos , Fotones , Radiografía Dental Digital/métodos , Evaluación de la Tecnología Biomédica , Tecnología Radiológica/normas
20.
Dentomaxillofac Radiol ; 28(4): 224-31, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10455386

RESUMEN

OBJECTIVES: To derive and test a method to predict Perceptibility Curves (PCs) for direct digital intraoral radiographic systems. METHODS: A test object was used to determine the performance of an average observer with respect to the threshold contrast and internal noise of the human visual system. These data were combined with system parameters to predict PCs mathematically. RESULTS: Data on the performance of an average observer could be defined to obtain values of the effective threshold contrast as a function of background gray level. This function combined with the gamma-value of the system predicted PCs that agreed well with PCs obtained in the conventional way. CONCLUSION: It is possible to predict PCs from a limited number of system parameters together with predetermined data on an average observer.


Asunto(s)
Radiografía Dental Digital , Percepción Visual , Artefactos , Predicción , Humanos , Modelos Teóricos , Reproducibilidad de los Resultados , Umbral Sensorial , Tecnología Odontológica , Tecnología Radiológica
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