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1.
J Hum Hypertens ; 17(12): 859-64, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14704730

RESUMEN

The C(-344)T promoter polymorphism of the human aldosterone synthase (CYP11B2) gene has been associated with hypertension and cardiac hypertrophy, but there were contrasting data. We analysed the genotype/phenotype associations between this polymorphism and cardiovascular variables in a young adult population, where interactions among genes, gene-environment, and acquired ageing-related organ damage are reduced. Anthropometric measurements, blood pressure, heart rate, left ventricular variables (by echocardiography), and carotid artery wall intimal-media thickness (by high-resolution sonography and digitalized morphometry) were taken in 420 white Caucasian students (mean age 23.5 years, s.d. 2.5 years). CYP11B2 alleles were detected by genomic polymerase chain reaction followed by digestion. Taking into account the three possible models of inheritance, we found no differences in the considered variables, except for an independent effect of the C(-344) allele on SBP in males (TT 125.6 (1.6), TC 128.4 (1.2) and CC 130.5 (2.2), mmHg, media (ES), P=0.03), and on interventricular septum thickness in diastole in females (CC 6.98 (0.12) vs TT 6.87 (0.09) and TC 6.87 (0.07), mmHg, P<0.01), in the codominant model. In conclusion, the CYP11B2 C(-344)T polymorphism appears to have a slight role in the cardiovascular phenotype of young healthy adults, even if these genotype/phenotype relationships might change with ageing.


Asunto(s)
Alelos , Enfermedades Cardiovasculares/genética , Citocromo P-450 CYP11B2/genética , Adulto , Análisis de Varianza , Antropometría , Presión Sanguínea , Distribución de Chi-Cuadrado , Femenino , Variación Genética , Genotipo , Humanos , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa
2.
J Hypertens ; 19(12): 2171-8, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11725160

RESUMEN

OBJECTIVES AND DESIGN: Angiotensinogen (AGT) gene variants influence angiotensinogen plasma levels in children and young adults. The angiotensinogen promoter (-6)A variant facilitates gene transcription in human tissues and it has been associated with high blood pressure in older adults. A young adult population can be used as a model to study genotype/phenotype associations between AGT (-6) variants and cardiovascular variables. METHODS AND RESULTS: Anthropometric measurements, blood pressure and heart rate were taken in 422 white Caucasian students (mean age 23.5 years, SD 2.5 years). Family history for hypertension, physical activity and smoking history were evaluated. Left ventricular variables were measured by echocardiography. Carotid artery wall intimal-media thickness (IMT) was measured by high resolution sonography and digitalized morphometry. The AGT G(-6)A alleles were evaluated by mutagenically separated polymerase chain reaction controlled by direct sequencing. No significant associations were found between angiotensinogen genotype and blood pressure, cardiac variables [except for deceleration time in females which increased with the number of (-6)A alleles] and IMT. Allele frequencies were similar between the first and third tertile of blood pressure and left ventricular mass, and were also similar between negative or positive family history for hypertension (the last group having significantly higher systolic blood pressure in males, P = 0.04 and diastolic blood pressure in females, P < 0.01). Moreover, no relevant interaction on the cardiovascular variables was found between AGT genotype and body mass index. CONCLUSIONS: The angiotensinogen G(-6)A variants do not affect cardiovascular parameters in young adults, but an effect of this polymorphism on cardiovascular phenotype (and hypertension) in older adults cannot be excluded. Additional factors, associated with ageing, should be present to unleash the supposed unfavourable potential of the (-6)A angiotensinogen variant.


Asunto(s)
Alelos , Angiotensinógeno/genética , Fenómenos Fisiológicos Cardiovasculares , Adulto , Presión Sanguínea , Arterias Carótidas/diagnóstico por imagen , Ecocardiografía , Variación Genética , Genotipo , Humanos , Fenotipo , Túnica Íntima/diagnóstico por imagen , Túnica Media/ultraestructura
3.
Skeletal Radiol ; 30(3): 138-43, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11357451

RESUMEN

OBJECTIVE: To evaluate the distribution and extent of wrist tendon alterations in patients with active rheumatoid arthritis (RA) using magnetic resonance imaging (MRI). DESIGN AND PATIENTS: Forty-three clinically active RA patients with an illness duration of less than 4 years and no clinical evidence of tendons tears were enrolled in the study. There were 10 men and 33 women, with an average age of 52 years (range 33-63 years). MRI of both wrists, with one exception, was performed at 1.0 T using T1- and T2-weighted sequences (slice thickness 3 mm). Twelve healthy subjects (8 women, 4 men; mean age 31 years) were also evaluated as a control group. Two radiologists reviewed each of four schematic anatomical regions (volar, dorsal, ulnar, radial) for the degree of tendon and tendon sheath alterations using two progressive scales. RESULTS: In the control group all tendons had homogeneous low signal intensity on all sequences. A small amount of fluid was found in six subjects but the diameter was always less than 1 mm. In the patient group minimal fluid (< 2 mm) was found in 35 (41%) wrists, grade 2 fluid (< 2 > 5 mm) in 26 (31%) and grade 3 fluid (> 5 mm) in 24 (28%). Fifty-nine (69%) of the grade 1 changes were in the volar compartment but grade 2 involvement was evenly distributed. Grade 3 changes were most common in the dorsal compartment and combined grade 2 and 3 in the dorsal and ulnar compartments were 32 (38%) and 25 (30%) compared with 16 (18%) and 17 (20%) respectively in the volar and radial compartments. The tendons were normal (grade 0) in 47 (46%) wrists. A maximum tendon signal change (grade 1) was demonstrated in 28 wrists (32%). When associated with other individual tendons grades this grade was demonstrated in the dorsal compartment in 30 (35%) wrists, in the volar compartment in 12 (14%), in the radial compartment in 17 (20%) and in the ulnar compartment in 26 (30%). A partial tear (grade 2) was detected in 7 (8%) wrists, all involving the dorsal and ulnar compartments; five underwent surgical repair and one proved to have a complete rupture of extensor digitorum. Three (3%) had a grade 3 complete tendon tear: all of these were in extensor tendons. Surgical repair was successful in one case but two ruptured again within 3 months. CONCLUSIONS: Low grades of peritendinous effusion were more common in the volar compartment whereas moderate and high degrees of tendon sheath fluid collection and/or pannus and signs of tendonitis were more frequent in the dorsal and ulnar tendon sheaths.


Asunto(s)
Artritis Reumatoide/patología , Imagen por Resonancia Magnética , Tendones/patología , Articulación de la Muñeca , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
Eur J Radiol ; 27 Suppl 2: S265-71, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9652533

RESUMEN

OBJECTIVE: To describe the rationale, the technical requirements and the examination technique of dynamic magnetic resonance studies of the breast and to assess the role of this method in the clinical diagnostic protocol. MATERIAL AND METHODS: We reviewed the relative literature and compared the results with our personal experience. RESULTS: The earliest reports on the possibility of differentiating carcinoma from benign tissue with magnetic resonance imaging came from Germany, where in 1986 Heywang and coworkers used T1-weighted spin-echo sequences before and after i.v. Gd-DTPA administration with an imaging time of approximately 5 mins and 5 mm slice thickness. With advances in magnetic resonance technology, Heywang Koebrunner adopted a static three-dimensional fast low-angle shot technique permitting < 3 mins' imaging time and providing high resolution with thin slices. This approach may detect even the carcinoma which occasionally does not enhance in the typical rapid, intense way. A review of 400 biopsy-proved lesions showed that all carcinomas enhanced strongly, all but 5% rapidly and 85% focally. Over 70% of benign masses exhibited no major contrast uptake, although some benign tumors and proliferative dysplasias enhanced strongly. At present, Heywang-Koebrunner use rapid three-dimensional gradient-echo sequences (TR/TE 14/7, FA 25 degrees; at 1.0 T) which have the advantages of three-dimensional imaging and permit dynamic studies (< 1 min/sequence). The same sequence is used at our institution. The dynamic technique is advocated by Kaiser who in 1989 reported preliminary sensistivity and specificity values over 95%. The time/signal intensity curves revealed the rapid and strong enhancement of malignancies, the gradual and strong enhancement of the only fibroadenoma studied, and the gradual and mild contrast uptake of benign dysplasia. In 1992, in nearly 1000 dynamic examinations, Kaiser and Reiser reported 98.3% sensitivity, 97.0% specificity, 82.1% predictive value and 97.2% accuracy. The combination of rapid acquisition with techniques that preserve high spatial resolution may improve specificity by allowing the study of lesion morphology as well as of enhancement patterns. A whole-breast imaging technique has been reported which permits acquisition times < 15 s by partial sampling of the central k-space region superimposed on high-resolution three-dimensional images. CONCLUSIONS: Dynamic magnetic resonance imaging of the breast is currently an important step of the clinical protocol of breast diseases, but there is no established study protocol yet.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Compuestos Heterocíclicos , Humanos , Procesamiento de Imagen Asistido por Computador , Compuestos Organometálicos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
5.
J Magn Reson Imaging ; 6(4): 589-95, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8835951

RESUMEN

Forty-one patients with 61 proved focal liver lesions underwent MRI of the liver at 1.0 T, with the aim of evaluating the usefulness of turbo spin-echo (TSE) sequences in characterizing focal liver lesions, by comparing them with conventional spin-echo (CSE) sequences. Two different TSE protocols were employed. with constant echo time and varying repetition time: TSE-S (3000 msec) and TSE-L (5100 msec). All images were evaluated quantitatively (signal-to-noise ration 'SNR') and qualitatively: because benign lesions were all liquid (12 cysts and 10 hemangiomas), they were well characterized morphologically on the basis of signal intensity. Mean SNR was significantly different between metastases and benign lesions (P < .0001) with all T2 sequences. Among the single T2 sequences tested, logistic regression analysis showed TSE-L to have the best predictive ability of the nature of focal lesions, with a G value of 42.02, compared to 29.87 of TSE-S and 25.55 of CSE second echo (SE II). The combination of TSE-L with TSE-S did not modify these results, whereas the combination of TSE-L with CSE only resulted in slight improvement (G = 46.95). Comparison of the receiver operating characteristic (ROC) curves showed only SE II (area under the ROC curve of .8312) to be significantly inferior to the best single sequence, or TSE-L (area under the ROC curve of .9176; P = .027). All sequences were equivalent in qualitative evaluation with good reproducibility, sensitivity ranging from .94 to 1.0 and specificity ranging from .86 to .93. This study confirms the value of TSE sequences in characterization of focal liver lesions. Time of acquisition is strongly reduced with these sequences, whereas results are fairly similar to those obtained with CSE. TSE sequences could therefore replace CSE for the study of focal liver lesions.


Asunto(s)
Aumento de la Imagen/métodos , Hepatopatías/diagnóstico , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Área Bajo la Curva , Artefactos , Quistes/diagnóstico , Femenino , Predicción , Hemangioma/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Modelos Logísticos , Masculino , Persona de Mediana Edad , Curva ROC , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Radiol Med ; 90(3): 219-25, 1995 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-7501825

RESUMEN

The clinical usefulness of Magnetic Resonance Imaging (MRI) of the knee in the depiction of meniscal, ligament and tendon lesions is well known. In contrast, the role MRI plays in the diagnosis of chondromalacia remains debated, the gold standard being arthroscopy. A new technique, i.e., MR arthrography (MRA), has been recently proposed which consists of the intraarticular injection of a paramagnetic contrast agent (Gd-DTPA) during MRI. Thirty-one patients with clinically suspected chondromalacia of the knee were examined with MRA. The exams were performed with a 1T superconductive magnet and a dedicated coil. All the patients were examined before (baseline scans) and after paramagnetic contrast agent injection. MRA results were compared with arthrographic findings. Baseline MRI had 25% sensitivity, 77.9% specificity and 83% diagnostic confidence in the diagnosis of chondromalacia; these figures increased to 93%, 97.6% and 91.5% after contrast agent injection. This preliminary experience confirms MRA to be a useful tool in the diagnosis of chondral knee conditions.


Asunto(s)
Enfermedades de los Cartílagos/diagnóstico , Cartílago Articular/patología , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Adulto , Anciano , Anciano de 80 o más Años , Artroscopía , Medios de Contraste , Femenino , Gadolinio , Gadolinio DTPA , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Ácido Pentético/análogos & derivados , Sensibilidad y Especificidad
7.
MAGMA ; 3(3-4): 143-50, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8749732

RESUMEN

The aim of this study was to compare conventional spin-echo (CSE) T2-weighted (T2W) images with turbo spin-echo (TSE) T2W pulse sequences in their ability to detect focal liver lesions. Seventy-eight consecutive patients with focal liver lesions were entered into this study. All patients were imaged using the gradient-echo (GE) sequence with the breath-hold technique for T1-weighted (T1W) images, and CSE and TSE sequences for T2W images. Qualitative evaluation included lesion detection (number of lesions detected) and conspicuity (extent of visualization of lesional borders); quantitative evaluation included the signal-to-noise (S/N) ratio and the contrast-to-noise (C/N) ratio. TSE showed the best performance in terms of lesion detection; however, the difference between TSE and CSE was significant only in the case of benign cysts (p < 0.01). Conspicuity was higher with TSE and CSE, and lower with GE. The S/N and C/N ratios of the two T2W sequences were also comparable, and better than those of GE. However, the combined use of GE and TSE resulted in improved lesion detection. The results show that, because the acquisition time is greatly reduced with TSE sequences, these should be considered as first-line approach to magnetic resonance imaging of the liver for the study of focal lesions.


Asunto(s)
Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética/métodos , Adenoma/diagnóstico , Adulto , Anciano , Enfermedades de los Conductos Biliares/diagnóstico , Carcinoma Hepatocelular/diagnóstico , Quistes/diagnóstico , Imagen Eco-Planar/métodos , Femenino , Hemangioma/diagnóstico , Humanos , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad
8.
AJR Am J Roentgenol ; 163(5): 1093-7, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7976881

RESUMEN

OBJECTIVE: Wedge-shaped areas of increased signal intensity surrounding focal hepatic lesions on T2-weighted images have been described as an occasional finding in patients with hepatic metastases. We reviewed MR images of patients with benign and malignant focal hepatic lesions to determine the prevalence and diagnostic significance of this finding, and in particular to determine if these wedge-shaped areas are characteristic of cancer. MATERIALS AND METHODS: One hundred twenty-one patients with focal hepatic lesions (65 patients with metastases, 14 patients with hepatocellular carcinoma, and 42 patients with benign conditions) underwent MR imaging of the liver at 1.0 T. Axial spin-echo T1-weighted and spin-echo and turbo spin-echo T2-weighted MR images were obtained. The MR images were retrospectively evaluated: the number and size of the lesions and the presence of wedge-shaped areas surrounding the lesions were recorded; in patients with cancer, follow-up MR images and a clinical course were used to study the evolution of the lesions and the adjacent wedge-shaped areas. The final diagnosis in patients with cancer was proved by clinical course (54 patients) or fine-needle aspiration biopsy (25 patients); in patients with benign lesions, the findings on various other imaging techniques were accepted as conclusive. RESULTS: The wedge-shaped areas were noted on T2-weighted images in 16 (25%) of 65 patients with metastases, in 3 (21%) of 14 patients with hepatocellular carcinoma, and in 5 (12%) of 42 patients with benign lesions. In 11 of the 16 patients with metastases and wedge-shaped areas of increased signal intensity, a metastatic lesion within the wedge-shaped area was detectable; in the remaining five patients, a metastatic lesion appeared during the subsequent clinical course. In some instances, the wedge-shaped area obscured the lesion. In patients with benign conditions, the wedge-shaped area was frequently seen in association with hemangiomas (4 of 13, 31%). CONCLUSION: Our results show that wedge-shaped areas of increased signal intensity surrounding lesions on T2-weighted MR images are a common finding in patients with focal hepatic lesions. The wedge-shaped areas cannot be considered pathognomonic of malignant lesions because they are also seen in patients with benign conditions (hemangioma, abscess). However, the appearance of these wedge-shaped areas in a patient with cancer should suggest a metastasis. The possibility that hepatic lesions could be obscured by these wedge-shaped areas also should be considered when response to treatment is being evaluated.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética , Adulto , Anciano , Biopsia , Carcinoma Hepatocelular/secundario , Femenino , Hemangioma/diagnóstico , Humanos , Hepatopatías/diagnóstico , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
9.
Radiol Med ; 87(5): 636-42, 1994 May.
Artículo en Italiano | MEDLINE | ID: mdl-8008895

RESUMEN

Turbo Spin-Echo (Turbo SE) pulse sequences represent a new type of fast sequences characterized by a dramatic reduction in acquisition time with similar intrinsic contrast to that of conventional Spin-Echo (SE) pulse sequences. For a preliminary clinical comparison of turbo SE and SE sequences, a consecutive series of 25 patients with focal liver lesions was investigated by means of MRI at 1.0 T. The patients were selected on the basis of US or CT positive liver scans for focal lesions. All patients underwent MRI following the same protocol: axial T1-weighted (T1W) gradient echo (GE) sequences (TR/TE = 110/6 ms) with the "breath-hold" technique, T2-weighted (T2W) SE sequences (TR/TE = 1730/90 ms; FL = 60, M = 128 x 256, 2 AC, TA = 7 min 26 sec) and turbo SE sequences (TR/TE = 5100/112 ms, M = 240 x 256, 2 AC, TA = 2 min 48 sec). Slice thickness was 10 mm with a 1-mm gap in all cases. Qualitative (number, size and definition of the lesions) and quantitative (contrast-to-noise ratio (CNR) and relative CNR) variables were considered. SE and turbo SE sequences demonstrated the same number of lesions; the smallest lesion (3 mm) was identified by turbo SE sequences. Turbo SE sequences better depicted lesion margins than SE sequences. In all cystic conditions, CNR was higher in turbo SE than in SE sequences, while it was lower in all the extant conditions. This preliminary experience proves turbo SE pulse sequences to be a valuable tool in liver MRI, which calls for further clinical trials.


Asunto(s)
Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Radiol Med ; 87(1-2): 36-40, 1994.
Artículo en Italiano | MEDLINE | ID: mdl-8128030

RESUMEN

We report and compare the results obtained with conventional imaging (mammography and US) and MRI in the study of 46 solid nodular breast lesions verified with histologic, cytologic and/or instrumental follow-up examinations for 12-34 months. The variables we compared were relative to the identification, nature and size of the lesions. MRI, which was performed on the basis of previous mammographic and US findings, detected all the lesions but never modified the diagnosis of conventional imaging methods. Questionable MR diagnoses were fewer than mammographic and US ones (2 versus 11), but its role in correcting the questionable diagnoses of conventional imaging methods was controversial. Particularly, of 11 such cases on mammographic and US images, MRI made 8 correct diagnoses but exhibited 2 false positives and 1 false negative for carcinoma. Such MR mistakes are likely to be related to the non-use of contrast medium. As for size, US was more accurate than mammography and MRI; yet, very few misdiagnoses were make on the whole.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Mama/patología , Imagen por Resonancia Magnética , Mamografía , Ultrasonografía Mamaria , Adolescente , Adulto , Anciano , Neoplasias de la Mama/epidemiología , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Italia/epidemiología , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/estadística & datos numéricos , Mamografía/instrumentación , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Ultrasonografía Mamaria/instrumentación , Ultrasonografía Mamaria/estadística & datos numéricos
11.
J Clin Oncol ; 11(12): 2451-5, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8246034

RESUMEN

PURPOSE: We prospectively evaluated the clinical efficacy of ultrasonography (US) in monitoring the effect of medical treatment in patients with liver metastases, by comparing serial US assessment with serial magnetic resonance imaging (MRI) evaluation and clinical outcome in a group of 41 patients with solid tumors. PATIENTS AND METHODS: Both examinations were performed in patients with metastatic liver disease at the start of a new treatment modality and monthly thereafter for 3 months; close monitoring was prolonged beyond the third month in cases in which there was disagreement between the two techniques and the clinical course was not conclusive. RESULTS: Planned follow-up was completed in 37 cases. There was limited concordance between the two examinations: in 21 cases only (56.8%), US and MRI gave concordant information on the evolution of hepatic metastases; in eight cases, both agreed on progression of disease (PD), in 11 cases on stable disease (SD), and in one case each on partial response (PR) and complete response (CR). In the remaining 16 cases (43.2%), there was disagreement between the two examinations. On the basis of subsequent clinical course, this discrepancy was shown to be due to US inadequacy in 13 cases and to MRI inadequacy in one case; in two cases, the clinical course was not conclusive. The most striking limits of US appeared to be twofold: (1) a progressive appearance, with chemotherapy, of a diffusely inhomogeneous structure of the liver, resulting in obscuration of focal lesions (and a subsequent judgement of CR) in cases in which lesions were, on the contrary, detected at MRI and usually confirmed by subsequent clinical course; and (2) false US-determined PD in cases in which lesions proven at baseline MRI were noted at US only after one to two courses of therapy. CONCLUSION: We conclude that US, which is known to be inaccurate for screening of liver metastases, is unreliable for the follow-up of metastatic liver disease; despite its wide availability, low cost, and noninvasiveness, critical therapeutic decisions should not be made based on the outcome of this test.


Asunto(s)
Neoplasias Hepáticas/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Resultado del Tratamiento , Ultrasonografía
12.
Histochem J ; 25(5): 384-91, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8100560

RESUMEN

We studied the cytochemical localization of particulate guanylate cyclase (GC) in rat adrenal gland after stimulation with porcine brain natriuretic peptide (pBNP) by electron microscopy. In the adrenal cortex, GC activity, as demonstrated by the presence of reaction product, was prevalently localized to the zona glomerulosa and zona fasciculata, while the zona reticularis showed little GC reaction product. In the adrenal medulla, GC reaction product was present only in adrenalin-containing cells. All GC positivity was associated with intracellular membranes. No GC reaction product was detected in specimens incubated in media devoid of pBNP. In parallel samples incubated in the presence of rat atrial natriuretic factor (rANF), the distribution of rANF-stimulated GC activity was similar to that of pBNP-stimulated GC activity.


Asunto(s)
Corteza Suprarrenal/enzimología , Médula Suprarrenal/enzimología , Guanilato Ciclasa/metabolismo , Proteínas del Tejido Nervioso/farmacología , Corteza Suprarrenal/efectos de los fármacos , Corteza Suprarrenal/ultraestructura , Médula Suprarrenal/efectos de los fármacos , Médula Suprarrenal/ultraestructura , Animales , Histocitoquímica , Microscopía Electrónica , Péptido Natriurético Encefálico , Ratas
13.
J Comput Assist Tomogr ; 16(4): 553-9, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1629413

RESUMEN

Twenty-four patients whose mediastinal (12 patients) and lung (12 patients) neoplasms were eventually verified were evaluated with cine MRI in addition to conventional methods (plain radiography, CT, MRI, and endoscopy). Using a 1.0 T system and gradient echo (FLASH repetition time 250-350 ms, echo time 12, flip angle 25-60 degrees) multislice pulse sequence, cine MRI was performed combined with cardiac gating. At the level of the pulmonary artery, the CT, spin echo (SE) MRI, and cine MRI findings were evaluated blindly by three groups of radiologists to determine whether the pulmonary artery was infiltrated or dynamically stenotic. Cine MRI allowed an overall diagnostic accuracy of 100% in comparison with SE MRI (91.6%) and CT (91.6%).


Asunto(s)
Imagen por Resonancia Magnética , Arteria Pulmonar/patología , Adolescente , Adulto , Anciano , Constricción Patológica , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Neoplasias del Mediastino/diagnóstico , Neoplasias del Mediastino/patología , Persona de Mediana Edad , Películas Cinematográficas , Invasividad Neoplásica , Sensibilidad y Especificidad
14.
Clin Exp Rheumatol ; 10(3): 217-22, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1582065

RESUMEN

The purpose of this study was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in rheumatoid arthritis (RA) by comparing MRI with conventional radiology (CR) findings and by correlating these findings with the clinical and serological profile of the disease. The hands of 31 patients (24 females, 7 males) affected by classical RA were studied using a Magnetom 1.0 T tomograph. Coronal, axial, and/or sagittal SE T1 and GE (FLASH 2D FL: 70 degrees-15 degrees) images were obtained in all patients. Moreover, in 7 patients the MRI study was performed after i.v. injection of Gd DTPA contrast medium (0.2 mM/kg). Ten healthy volunteers were also studied as controls. In all patients a conventional radiological study was performed as well as a clinical and serological investigation. Two blinded observers evaluated the MRI and CR findings and checked 15 elementary pathological lesions, assigning an MRI and a CR score to each patient. MRI provided higher accuracy than CR in detecting rheumatoid soft tissue changes and minimal skeletal lesions, while the opposite was true for severe skeletal lesions. No correlations emerged between the MRI/CR findings and clinical and serological data. This study suggests that MRI and CR are complementary techniques in the evaluation of the anatomical changes in RA.


Asunto(s)
Artritis Reumatoide/diagnóstico , Mano , Imagen por Resonancia Magnética , Adulto , Artritis Reumatoide/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía
15.
Radiol Med ; 83(1-2): 24-30, 1992.
Artículo en Italiano | MEDLINE | ID: mdl-1557539

RESUMEN

The authors report their experience with cine-MRI in evaluating the infiltration of the main cardiovascular structures by expansive mediastinal masses. Twenty-four patients with proven lung (12 cases) and mediastinal (12 cases) cancers, previously selected with CT, underwent MRI examination of the chest. A superconductive 1.0 T unit was employed. Cytohistologic confirmation was obtained in all cases (6 thymomas, 6 lymphomas, 12 lung cancers). Ten normal subjects were also studied as a control group. Axial, coronal, and sagittal SE T1 images were obtained as the basis for MRI investigation of the chest. Subsequently, gradient-echo pulse-sequences images were obtained during the whole cardiac cycle, and later displayed on cine-Mode, on the section plane where vessel wall was closest to the tumor. The results prove cine-MRI to allow a correct diagnosis to be made in all cases, especially in those patients where CT and conventional SE MRI yielded questionable results. This preliminary experience suggests that cine-MRI could be used as a complementary method to CT and conventional SE MRI in evaluating mediastinal vessel involvement.


Asunto(s)
Sistema Cardiovascular/patología , Imagen por Resonancia Magnética/métodos , Neoplasias del Mediastino/diagnóstico , Películas Cinematográficas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética/instrumentación , Masculino , Neoplasias del Mediastino/patología , Persona de Mediana Edad , Películas Cinematográficas/instrumentación , Invasividad Neoplásica , Estadificación de Neoplasias
16.
Ital J Orthop Traumatol ; 18(1): 123-7, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1399527

RESUMEN

Diagnosis of carpal tunnel syndrome (CTS) is usually made on the basis of clinical and electrophysiologic data. Other tests, however, such as ultrasound and CT, have enabled us to acquire additional information regarding the anatomical definition of the structures inside the carpal tunnel. The superior quality of MRIs soft-tissue definition led us to employ it in cases of median nerve compression at the wrist in order to determine its true diagnostic value. We compared the preoperative electrophysiologic and MRI findings in 23 cases of CTS which had undergone surgical decompression of the median nerve at the wrist. Exact correspondence with the intraoperative findings confirmed the reliability of the anatomical information provided by MRI, yet the same comparison revealed that correct "functional" information could be provided only by the electrophysiologic tests.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico , Adulto , Anciano , Síndrome del Túnel Carpiano/fisiopatología , Síndrome del Túnel Carpiano/cirugía , Humanos , Imagen por Resonancia Magnética , Nervio Mediano/fisiopatología , Nervio Mediano/cirugía , Persona de Mediana Edad , Conducción Nerviosa
17.
Radiol Med ; 82(4): 422-6, 1991 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-1767046

RESUMEN

MR imaging was employed for the identification and tissue characterization of nodular lesions in the breast. The study had poor outcome, but the clinical introduction of a paramagnetic contrast medium, Gd-DTPA, allowed better results to be obtained. This study was aimed at evaluating the possibilities of Gd-DTPA enhanced MRI in differentiating benign from malignant breast nodules and in staging cancer. Final diagnosis was made by means of either histology, in the patients who underwent surgery, or cytology. Sixty-one patients with nodules at mammography and US were examined with MRI. The results of US, mammography, and MRI were blindly evaluated and proved that combined mammography and US, together with Gd-DTPA enhanced MRI, correctly identified all nodular lesions. Moreover, enhanced MRI allowed benign lesions to be distinguished from malignant nodules. MRI with Gd-DTPA correctly assessed both T parameter and pectoral muscle infiltration. MRI cannot replace mammography, which is a quick and inexpensive examination, but it should be performed as an adjunct in the cases of questionable radiographic and US findings and to stage breast cancer.


Asunto(s)
Enfermedades de la Mama/diagnóstico , Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética , Adulto , Anciano , Medios de Contraste , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Gadolinio DTPA , Humanos , Persona de Mediana Edad , Compuestos Organometálicos , Ácido Pentético
18.
Radiol Med ; 82(1-2): 35-9, 1991.
Artículo en Italiano | MEDLINE | ID: mdl-1896578

RESUMEN

Thirty-four selected patients were evaluated in order to define MRI capabilities in the preoperative evaluation and characterization of the pathogenetic patterns of carpal tunnel syndrome (CTS). MRI examinations were performed by means of a superconductive unit (1.0 T, Magnetom): SE T1 (500/17) and T2 (2000/90) axial images of the carpal region were obtained with a round surface coil. In 8 patients 3D GE (FLASH) pulse sequences were used to obtain 32 images of the hand; 3D reconstruction was also applied. Six patients with rheumatoid arthritis and amyloidosis were also studied after i.v. injection of Gd-DTPA (0.2 mM/kg). MRI findings were compared with both clinico-electrophysiologic and surgical results. High agreement was observed only between MRI and surgical findings. MRI allowed the direct demonstration of carpal tunnel abnormalities in 8 cases, while abnormal findings in the median nerve were observed in 18 patients. The possibility of depicting medial nerve lesions on T2-weighted images when no direct demonstration of the cause of compression is possible, could represent a guideline for the etiopathogenetic investigation of CTS. However, further experience in selected patients is necessary to define all the aspects relative to this very common syndrome.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico , Imagen por Resonancia Magnética , Adulto , Anciano , Síndrome del Túnel Carpiano/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios
19.
Radiol Med ; 81(5): 601-4, 1991 May.
Artículo en Italiano | MEDLINE | ID: mdl-2057583

RESUMEN

MR imaging, like other imaging techniques, can cause emotional and psychological reactions in the patients. Although reversible, these reactions sometimes lead the patient to absolutely refuse the examination or to make it impossible to carry it through. To investigate the patients' emotional distress, a study group of 28 subjects was examined. They were heterogeneous in sex, age, and pathologic condition. The main psychological reactions were analyzed, and anxiety--both of state and of trait. The anxiety parameter was evaluated as a specific index in the psycho-behavioral modifications induced by MR examination. The influence was also considered of the "fantasies" related to examination results on the patients' psyche. Talks and STAI X1 and STAI X2 were employed to this purpose, to identify possible disturbing elements related to both patients' character and examination situations. Our results point to anxiety as the major reaction observed in the subjects undergoing MR examination; it seems to be related to different parameters, which are difficult to identify. Claustrophobia, pathofobia, and the fear of an unknown examination play a major role. Talking to the patients and informing them of the characteristics of the examination proved useful to significantly reduce their emotional distress.


Asunto(s)
Ansiedad , Imagen por Resonancia Magnética/psicología , Estrés Psicológico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Radiol Med ; 81(4): 396-403, 1991 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-2028029

RESUMEN

The purpose of this study was to evaluate MRI diagnostic accuracy in rheumatoid arthritis (RA), to compare MRI and radiological findings and to correlate these findings with the clinical and serological profile of the disease. The hands of 24 patients (20 females, 4 males) affected with typical RA (ARA criteria) were studied using a tomograph Magnetom 1.0 T Siemens. Two patients affected with RA refractory to conventional second-line drugs who received a bolus of methylprednisolone (1 g) were studied before and after such treatment. The hands of healthy volunteers were examined as controls. Besides MRI study all patients underwent: (1) radiological examination of the hands performed with a standard technique and (2) clinical and serological investigation aimed at characterizing diseases activity and extent. The radiographic and MRI findings were evaluated by two different observers who found 15 pathological elementary lesions and assigned a MRI and a radiological score to each patient. MRI exhibited significantly higher accuracy than radiography in evaluating rheumatoid soft-tissue changes and in detecting minimal skeletal lesions, while severe skeletal lesions were better detected by radiology. No correlation was found between pathological MRI findings, radiological results and clinical or serological data. A significant drop in soft-tissue effusion was observed after methylprednisolone pulse in two patients. This study confirms MRI potential in the study of rheumatoid joint lesions and in the early detection of minimal soft-tissue changes. Its use appears to be suitable for accurate monitoring of RA patients under specific therapy.


Asunto(s)
Artritis Reumatoide/diagnóstico , Deformidades Adquiridas de la Mano/diagnóstico , Imagen por Resonancia Magnética , Adulto , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/tratamiento farmacológico , Femenino , Deformidades Adquiridas de la Mano/diagnóstico por imagen , Humanos , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Radiografía , Factores de Tiempo
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