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OBJECTIVE: Glucocorticoid excess is widely recognized as one of the most important causes of bone loss. The mechanism of glucocorticoid-induced osteoporosis is presumably multifactorial, and consists of the loss of organic and non-organic compounds. Efforts have been made to develop simple physical methods for the assessment of bone tissue for the screening of subjects at high risk of osteoporosis, without the use of radioactive sources or ionizing radiation. Quantitative ultrasonometry (QUS) has been suggested as a useful method for monitoring patients undergoing glucocorticoid therapy, which is the most common cause of glucocorticoid excess. QUS appears to detect more structural bone changes than the traditional methods and allows assessment of bone density and elasticity, both characteristics influenced by organic and non-organic bone compounds. However, the use of QUS has not yet been extensively investigated in subjects with endogenous cortisol excess. The aim of this study was to evaluate the usefulness and predictive power of QUS in assessing bone loss in subjects with differing degrees of endogenous cortisol excess due to adrenal mass. DESIGN: Thirty-four patients (20 women and 14 men) aged between 21 and 59 years were evaluated; fifteen (9 women and 6 men; median age, 42 years) were affected by overt Cushing's syndrome (CS) and nineteen (11 women and 8 men; median age, 44 years) by subclinical CS, defined as lacking clinical signs of hormone excess despite the presence of at least two abnormalities in hypothalamic-pituitary-adrenal axis function, as assessed by routine endocrine tests. All women included were eumenorrhoic. METHODS: QUS measurement of amplitude-dependent speed of sound was performed on the 2nd to 5th proximal phalanges of the non-dominant hand using a DBM Sonic 1200R bone profiler (Igea S.r.l, Italy). The results were compared with bone density assessed on lumbar vertebrae (L1-L4) and femoral neck sites by dual-energy X-ray absorptiometry (DEXA). RESULTS: A strongly significant bone loss was detected by finger QUS measurement when the patients were considered either all together or as two subgroups (P<0.001, all). The bone density decrease in the fingers was similar to that found at the lumbar spine and femoral neck by the DEXA technique. Lumbar and finger Z-scores correlated inversely with 24 h urinary free cortisol (UFF) excretion (P<0.01, both). Finger Z-scores also correlated inversely with the estimated duration of subclinical CS (P<0.05). Concerning disease activity, only UFF was confirmed by multivariate analysis to be an independent factor influencing bone loss (P<0.05). A positive correlation between the results of the two techniques was found in controls (P<0.05) but not in patients. The lack of correlation between the two techniques in patients can probably be attributed to the different parameters of bone alteration measured by the techniques. CONCLUSIONS: The detection of bone loss in subclinical CS similar to that in overt CS suggests that all subjects with endogenous cortisol excess should be evaluated for bone mass. QUS measurement appears to be a reliable, radiation-free, simple and fast tool for the identification of bone alteration in subjects with endogenous cortisol excess.  相似文献   
63.

Objectives

To assess the significance of a paradoxical pattern (PP) (greater tracer uptake during stress than at rest) on gated myocardial perfusion SPECT in myocardial regions with myocardial necrosis.

Methods

A review of 1,764 consecutive stress-rest myocardial perfusion SPECT studies in patients with prior myocardial infarction (MI) was conducted. Of these, 117 patients (6.6%) with a PP corresponding to a region with myocardial necrosis were identified. An assessment of perfusion, contractility, wall thickening, scintigraphic criteria for viability, and the characteristics of the culprit artery in regions with a PP was performed.

Results

Of the 160 regions with necrosis, 125 (75%) had a PP: 67 in the anterior region and 58 in the inferior-lateral region. In the PP group, the average tracer activity of defects during stress was significantly higher than at rest (P?<?.0001). Ninety-three (86.6%) out of 110 PP segments without scintigraphic criteria of viability at rest met viability criteria on stress imaging. The artery supplying regions with a PP was patent in 88% of cases. In the remaining patients it was occluded, although collateral circulation was always present.

Conclusions

In scintigraphic segments corresponding to regions with infarction and PP, a mixture of viable and well perfused myocardium was observed. In most cases, the vessel that supplied the region with PP was either patent, or when the artery was occluded, there was evident collateral circulation.  相似文献   
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OBJECTIVES: To propose our clinical classification of malignant ethmoid tumors and to compare it with the last American Joint Committee on Cancer (AJCC)-Union Internationale Contre le Cancer (UICC) classification, published in 1997. DESIGN: Retrospective review. SETTING: Tertiary cancer facility. PATIENTS: We evaluated 123 consecutive patients undergoing craniofacial resection for malignant ethmoid tumors involving the anterior skull base. The mean follow-up was 60 months. Fifty-nine patients (48%) presented with recurrent disease after prior therapy. We classified them with a new classification system (Istituto Nazionale per lo Studio e la Cura dei Tumori) based on the most commonly accepted unfavorable prognostic factors (involvement of dura mater; intradural extension; involvement of the orbit and, in particular, of its apex; invasion of maxillary, frontal, and/or sphenoid sinuses; and invasion of the infratemporal fossa and skin. We also classified patients with the AJCC classification published in 1997. MAIN OUTCOME MEASURES: Disease-free status and overall survival rate. To study a possible association with tumor stage, the Cox regression model was adopted. RESULTS: According to our classification, patient distribution by tumor type was T2, n = 46; T3, n = 29; and T4, n = 48 (no T1 tumors were present in the series). For previously untreated patients, 5-year disease-free survival estimates were T2, 57%; T3, 50%; and T4, 13%. For relapses, corresponding figures were T2, 31%; T3, 23%; and T4, 1%. The prognostic difference among stages was statistically significant (P<.001). Similar results were obtained for overall survival. In contrast, patient distribution among different AJCC stages was less balanced, and we failed to detect a significant association with the clinical outcome using this classification. CONCLUSION: We propose the use of our staging system by all those specialists in the field willing to validate the classification and possibly apply it for clinical and investigational purposes.  相似文献   
66.
We prospectively evaluated the frequency of lymphadenopathy in the right upper abdominal quadrant as detected by sonography in 650 consecutive unselected patients, after excluding patients with a known lymphoma or abdominal carcinoma and patients with acquired immunodeficiency disease. Evidence of enlarged lymph nodes (few in number, with an elongated shape and isoechoic to the liver, 8 to 22 mm in size), found primarily in the gastrohepatic ligament and porta hepatis, was seen on sonographic scans in 106 patients (16.3%). Associated conditions in 69 of 106 patients (65%) were hepatobiliary or pancreatic diseases and, less frequently, other benign entities (12 patients; 11.3%); in 25 cases (23.5%) no significant abdominal or systemic disease was present. Comparison with CT or surgical findings, or both, was available in 36 cases. We conclude that lymphadenopathy in the right upper abdominal quadrant may be found in relation to different non-neoplastic conditions as well as in the absence of any significant intra-abdominal disease. The frequency of this finding on sonographic scans must be recognized to prevent misdiagnosis of lymphoma or metastatic disease as well as to avoid overstaging of local (hepatobiliary, pancreatic, gastric) neoplasms.  相似文献   
67.
MRI of the optic nerves was obtained in 13 patients with acute optic neuritis and 13 with a previous optic neuritis (ON), assessed by clinical features, visual fields and visual evoked potentials. Results of the conventional short tau inversion recovery (STIR) sequence obtained with a short echo time (STE-STIR; 22 ms) were compared with those of a long echo time (LTE-STIR: 80 ms) sequence. The conventional STE-STIR sequence revealed lesions in the optic nerves in 78.5% of acute and 58.8% of previous ON. The LTE-STIR sequence showed abnormalities in 92.8% of acutely symptomatic nerves and 94.1% of nerves with previous ON. The optic nerve lesions appeared significantly longer with the LTE-STIR sequence than with the conventional STE-STIR sequences, in both acute and previous ON.  相似文献   
68.
Prevalence of Hepatitis C Virus Antibodies in Italian Blood Donors   总被引:3,自引:0,他引:3  
11,117 blood donors from 24 blood transfusion services evenly distributed throughout the various Italian regions were tested for the presence of hepatitis C virus (HCV) antibodies in the serum and serum alanine aminotransferase (ALT) level. The results are as follows: (1) anti-HCV seroprevalence in Italy was 0.87% with a difference between Northern and Southern regions (0.68 vs. 1.37%) and between younger and older subjects (0.62 vs. 1.21%); (2) prevalence of elevated ALT levels was 4.74% without a North-South effect (except than for markedly elevated ALT levels); (3) anti-HCV seroprevalence was higher in subjects with elevated ALT (5.0%), with a North-South effect (2.2 vs. 9.9%) and particularly high (19.2%) in subjects with markedly elevated ALT; (4) ALT levels were elevated in 26.2% of anti-HCV positive subjects, with a North-South effect (14 vs. 40.5%).  相似文献   
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