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81.
AIMS: To evaluate possible modifications in the manganese superoxide dismutase (MnSOD) activity during neoplastic transformation of a cirrhotic liver and to find out whether its assessment may have predictive value to identify cirrhotic patients at a higher risk of hepatocellular carcinoma (HCC). METHODS: Seventy-one consecutive subjects with Child-Pugh class A liver cirrhosis were recruited. At the time of enrolment, HCC was diagnosed in 20 cirrhotic patients. The 51 cirrhotic patients without HCC were followed up for the occurrence of tumour by 6-monthly screening for 7 years. During follow-up, 16 patients developed HCC. Seventy healthy subjects formed the control group. MnSOD activity was assayed spectrophotometrically. RESULTS: Serum MnSOD activity was significantly lower in 70 healthy subjects compared with 51 cirrhotic patients and 20 cirrhotic patients with HCC. Cirrhotic patients who developed HCC during follow-up showed significantly higher values of MnSOD activity than HCC-free patients. The best cut-off of MnSOD activity was 0.40 U/ml. At this cut-off, chi2 analysis revealed that MnSOD activity was significantly different between the HCC-free cirrhotic patients and cirrhotic patients who developed HCC. CONCLUSION: The present findings suggest that during neoplastic transformation of cirrhotic liver, an increase in MnSOD activity may occur already during the precancerous phase, making this enzyme a probable malignancy-associated parameter.  相似文献   
82.
OBJECTIVE: The presence of 21-hydroxylase autoantibodies (21OHAb) is a marker of adrenal autoimmunity and can be used to identify subjects with pre-clinical Addison's disease. The low-dose (1 microg) ACTH test (LDT) is more sensitive than the high-dose (250 microg) test (HDT) for the diagnosis of pituitary adrenal insufficiency, but no information is available on the use of a LDT in subjects with autoimmune adrenalitis and primary adrenal insufficiency. The aim of our study was to evaluate the clinical use of the LDT in the diagnosis of early adrenocortical dysfunction in patients with adrenal autoantibodies. DESIGN AND METHODS: Firstly, we evaluated the cortisol responses to both a LDT and a HDT in a group of 12 healthy volunteers. We then performed a LDT in 11 subjects positive for 21OHAb, but without clinical signs of Addison's disease identified by screening 920 patients with one or more organ-specific autoimmune diseases. In all cases, the LDT was followed by a sequential HDT which was used as a control test of the sensitivity and specificity of the LDT. RESULTS: In healthy subjects, the peak cortisol levels after the LDT were similar to those after the classical HDT. In 21OHAb-positive subjects, the LDT showed a pathological response in five out of 11 (45%) cases and the diagnostic concordance between the results of the LDT and those of the HDT was 100%. All the five cases with pathological LDT were also positive for adrenal cortex autoantibodies (ACA) and 4/5 had high levels of basal ACTH. One subject with pathological LDT developed clinical Addison's disease 4 months after the test had been performed. CONCLUSIONS: Our study demonstrates that the low dose ACTH test has a high diagnostic sensitivity and specificity for primary adrenal insufficiency and suggests that it can accurately identify subjects with pre-clinical adrenal dysfunction.  相似文献   
83.
Hexarelin (HEX) and GHRP-2 are two synthetic hexapeptides, superanalogs of GHRP-6, belonging to GH secretagogue (GHS) family. GHS act via specific receptors at both the pituitary and the hypothalamic level to stimulate GH release both in animals and in humans. However, GHS also possess significant PRL- and ACTH/cortisol-releasing activity. Tyr-Ala-HEX as well as Tyr-Ala-GHRP-6 are, in turn, synthetic octapeptides generally used to perform binding studies because of their easy iodination. However, their endocrine activities have never been studied in humans. To clarify the endocrine activities of Tyr-Ala-HEX, in 7 young adult volunteers we compared the effects of the maximal effective dose of HEX (2.0 microg/kg i.v.) or GHRP-2 (2.0 microg/kg i.v.) with the same one of Tyr-Ala-HEX on GH, PRL, ACTH and cortisol levels. Basal GH, PRL, ACTH and cortisol levels in all testing sessions were similar. The administration of placebo did not modify hormonal levels. HEX and GHRP-2 administration induced the well known strong GH response (Cmax, mean+/-SE: 77.3+/-6.0 and 74.1+/-12.1 microg/l; AUC, mean+/-SE: 2596.7+/-251.1 and 2480.0+/-343.6 microg*min/l). These responses were similar to that induced by Tyr-Ala-HEX (63.7+/-18.5 microg/l; 1986.6+/-622.4 microg*min/l). Moreover, HEX, GHRP-2 and Tyr-Ala-HEX had the same significant stimulatory effect on PRL (14.9+/-2.5, 12.3+/-2.0 and 10.0+/-1.5 microg/l; 497.8+/-61.8, 480.4+/-66.9 and 415.8+/-58.5 microg*min/l), ACTH (48.0+/-10.1, 51.4+/-10.6 and 44.9+/-12.2 pg/ml; 1531.6+/-235.7, 1586.7+/-277.0 and 1338.1+/-164.5 pg*min/ml) and cortisol (179.9+/-10.0, 181.2+/-14.1 and 149.7+/-20.1 microg/l; 8465.0+/-406.6, 8689.2+/-788.1 and 6295.2+/-797.0 microg*min/l). Also the mean Tmax of the endocrine responses to HEX, GHRP-2 and Tyr-Ala-HEX were similar. In conclusion, the present results demonstrate that in humans Tyr-Ala-HEX is a GH secretagogue as potent as HEX and GHRP-2, two GHRP-6 superanalogs. Tyr-Ala-HEX also shares with HEX and GHRP-2 the same PRL- ACTH- and cortisol-releasing activity.  相似文献   
84.
AIMS: Psoriasis is a chronic, remitting and relapsing inflammatory disorder, involving the skin, nails, scalp and mucous membranes, that impairs patients'' quality of life to varying degrees. Psoriatic arthritis is a chronic seronegative, inflammatory arthritis, usually preceded by psoriasis. Temporomandibular disorders is a generic term referred to clinical conditions involving the jaw muscles and temporomandibular joint. The aim of this study was to assess symptoms and signs of temporomandibular disorders in psoriasis patients with and without psoriatic arthritis.METHODS: The study group included 112 patients (56 men, 56 women; median age 49.7±12 years) with psoriasis, 25 of them were affected by psoriatic arthritis. A group of 112 subjects without psoriasis (56 men, 56 women; median age 47.7±17 years) served as controls. Signs and symptoms of temporomandibular disorders were evaluated according to the standardized Research Diagnostic Criteria for Temporomandibular Disorders. Psoriasis patients were subgrouped according to the presence/absence of psoriatic arthritis and by gender, to assess the prevalence of traditional symptoms and signs of temporomandibular disorders.RESULTS: Patients with psoriasis, and to an even greater extent those with psoriatic arthritis, were more frequently affected by symptoms and signs of temporomandibular disorders, including an internal temporomandibular joint opening derangement than healthy subjects. A statistically significant increase in symptoms of temporomandibular disorders, in opening derangement, bruxism and sounds of temporomandibular joint was found in patients with psoriatic arthritis as compared with psoriasis patients without arthritis and controls.CONCLUSIONS: psoriasis seems to play a role in temporomandibular joint disorders, causing an increase in orofacial pain and an altered chewing function.  相似文献   
85.
Clinical and Experimental Medicine - Patients with lymphoproliferative disorders, candidate to autologous stem cell transplantation (ASCT), require mobilization with chemotherapy and granulocyte...  相似文献   
86.
The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.  相似文献   
87.
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The introduction of biological therapies, particularly anti-TNFα agents, has revolutionized the management of inflammatory bowel disease in those cases which are refractory to conventional treatment; however these drugs are not risk-free and their use has substantially increased the cost of treatment. As marketing protection expires for original, first-generation biopharmaceuticals, lower-cost “copies” of these drugs produced by competitor companies—referred to as biosimilars—are already entering the market. In September 2013, the European Medicines Agency approved two infliximab biosimilars for treatment of adult and paediatric inflammatory bowel disease patients, a decision based largely on efficacy and safety data generated in studies of patients with ankylosing spondylitis and rheumatoid arthritis. For many clinicians, extrapolation practices and the general question of interchangeability between biosimilars and reference biologics are cause for concern. In the present paper, the Italian Group for inflammatory bowel disease presents its statements on these issues, with emphasis on the peculiar clinical characteristics of inflammatory bowel disease and the importance of providing physicians and patients with adequate information and guarantees on the safety and efficacy of these new drugs in the specific setting of inflammatory bowel disease.  相似文献   
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