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Spinsanti P de Grazia U Faggioni A Frati L Calogero A Ragona G 《Leukemia & lymphoma》2000,38(5-6):611-619
54.
Chronic hepatitis C virus infection is currently the most common cause of end stage liver disease worldwide. Although the conclusions of the last National Institutes of Health Consensus Development Conferences on Hepatitis C have recently been published, several important issues remain unanswered. This paper reviews the available data using an evidence-based approach. Current evidence is sufficient to recommend IFN treatment for all patients with acute hepatitis. A later initiation of therapy yields the same likelihood of response as early treatment. A daily induction dose during month 1 is the best treatment option. The current gold standard of efficacy for treatment-naive patients with chronic hepatitis C is the combination of pegylated IFN and ribavirin. The overall sustained viral response rate to these regimens is 54 - 56% following a 48-week course of therapy. Patients with genotype 1 infection will have a 42 - 51% likelihood of response to 48weeks of therapy. Those with genotypes 2 or 3 infection will respond to 24weeks in 78 - 82% of cases. Debate continues regarding the optimal dose and duration of peginterferon (PEG-IFN), not only in patients infected with genotype 2 or 3 but also in those infected with genotype 1. The optimal dose of ribavirin has yet to be determined. Available data show the need to give the highest tolerable doses (1000-1200mg/day) to the difficult-to-treat patients (genotype 1, cirrhotics, obese), although there is a greater likelihood of intolerance. Genotypes 2 and 3 may receive 800mg/day, which is also the most appropriate lower dose for those patients who require dosage modification for anaemia or other side effects. Tolerability and compliance to therapy are still a problem, as approximately 15- 20% of patients within trials and > 25% in clinical practice withdraw from therapy. New PEG-IFNs are more effective than conventional IFN in improving liver histology. Monotherapy with PEG-IFN induces a marked reduction in staging in virological sustained responders, and to a lesser degree in relapsers, but provides no benefit to nonresponders after 24-48weeks of treatment. The use of maintenance therapy in virological nonresponders aiming to improve histology should be considered experimental and of unproven benefit. Pooling data from the literature suggests a slight preventive effect of IFN on hepatocellular carcinoma development in patients with HCV-related cirrhosis. The magnitude of this effect is low and the observed benefit may be due to spurious associations. The preventive effect is more evident among sustained responders to IFN. 相似文献
55.
Magnano A Privitera A Calogero G Nanfito' L Basile G Sanfilippo G 《Journal of pediatric surgery》2005,40(10):e25-e27
Solitary small intestine hemangiomas are rare and usually present with overt bleeding or chronic anemia. Diagnosis is usually difficult because traditional imaging techniques often lack accuracy. Capsule endoscopy is a new diagnostic tool that has showed greater sensitivity than other methods to reveal causes of bleeding in the small intestine. A case of hemangioma of the ileum in a 13-year-old boy is presented. Capsule endoscopy allowed diagnosis and planning of surgical treatment. 相似文献
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57.
Annovazzi A Bagni B Burroni L D'Alessandria C Signore A 《Nuclear medicine communications》2005,26(7):657-664
Different nuclear medicine modalities are currently used to study inflammatory and infective disorders of the abdomen. They are usually complementary to radiology and endoscopy, but they play a pivotal role in particular clinical situations. Several radiopharmaceuticals (e.g., 111In or 99mTc labelled white blood cells, monoclonal antibodies, human polyclonal immunoglobulins, 75Ga citrate) are commercially available, but they can not be used indifferently to study abdominal inflammatory disorders. The lack of comparative studies showing the accuracy of each radiopharmaceutical for the study of inflammatory/infective abdominal diseases does not allow the best nuclear medicine technique(s) to be chosen in an evidence-based manner. To this end we performed a meta-analysis of peer reviewed articles published between 1984 and 2004 describing the use of nuclear medicine imaging for the study of inflammatory bowel disorders, appendicitis and vascular graft infections. A guideline for the optimal radiopharmaceutical(s) to be used in each clinical condition and for different aims is provided. 相似文献
58.
Colonna-Romano G Aquino A Bulati M Lio D Candore G Oddo G Scialabba G Vitello S Caruso C 《Experimental gerontology》2004,39(10):1439-1446
Gamma/delta T lymphocytes cells recognize the antigen in a non-classical way and are considered the third branch of the immune system devoted to defend the integrity of the body. Ageing is characterized by an impairment of the main way of protection (the adaptive branch) but, successfully aged people show compensatory mechanisms of defense such as proneness to inflammation. Moreover, very old subjects show an increased number of NK cells. We have previously demonstrated that gamma delta T lymphocytes are reduced in elderly. In the present paper we have studied some characteristics of these cells to evaluate the possibility that these cells might balance the decreased action of the adaptive branch in successfully aged people. Cytofluorimetric analysis of cells collected from young, old and centenarian subjects has been used to evaluate the ability of these cells to expand in vitro. Here we demonstrate that gamma delta T cells are impaired in the ability to proliferate to different stimuli such as isopentenyl pyrophoshate, that select gamma delta T lymphocytes bearing delta 2 chain, other than to phytohemagglutinin and anti-CD3 that are polyclonal activators. Moreover, we demonstrate that gamma delta T cells in aged and centenarians show an enhanced sensitivity to undergo apoptosis induced both by alpha-Fas and TNF-alpha. All together these data suggest that gamma delta T lymphocytes are impaired in elderly and suggest that the reduced ability to proliferate and the reduced number of circulating gamma delta T lymphocytes is due to the proneness to apoptosis. Finally on the basis of these data, we conclude that gamma delta T lymphocytes, do not participate in the remodeling of the immune system due to the reduction of classical T cell response and replacement by NK cells in elderly. 相似文献
59.
Palli D Masala G Mariani-Costantini R Zanna I Saieva C Sera F Decarli A Ottini L 《European journal of cancer (Oxford, England : 1990)》2004,40(16):2474-2479
The association of male breast cancer (MBC) with a positive breast cancer (BC) family history and with BRCA1/2 germ-line mutations points to a genetic component; a relationship with occupation has also been reported. Recently, we identified pathogenetic BRCA1/2 mutations in a population-based series of Italian MBC patients: here in, we investigated interactions between a carrier status for BRCA1/2 mutations and occupation using a case-case design and estimating case-only odds ratios (CORs). Truck-driving was the most frequent occupation (3/4 BRCA-related cases and 2/19 unrelated cases). An interaction between carrier status and working as a truck-driver emerged, when we classified MBC cases as "ever/never-held" this job title (COR 25.5; 95% Confidence Limits (CL): 1.1-1,412.5) or according to truck-driving as the "longest-held" work (COR 54.0; 95% CL: 1.6-2,997.5). The possible modifying effect on MBC risk in subjects carrying BRCA1/2 germ-line mutations of an occupation characterised by exposure to chemicals such as polycyclic aromatic hydrocarbons (PAH) that are capable of inducing DNA damage, may provide clues to the role of environmental exposures in modifying BC risk in mutation carriers in both genders. 相似文献
60.
Di Lorenzo G Pacor ML Esposito Pellitteri M Listì F Colombo A Candore G Mansueto P Lo Bianco C Ditta V Battista Rini G Caruso C 《Mechanisms of ageing and development》2003,124(4):445-448
The literature on immunosenescence has focused mainly on T cell impairment. However, it is well known that B function is also profoundly affected. In particular, several studies have shown age-related changes in immunoglobulin serum levels. Concerning allergic diseases, the incidence of onset of allergic symptoms, as well as their severity, seems to decrease with age. So, the decline of onset of allergic symptoms observed in ageing might result from a decrease of serum total IgE due to an unbalance of cytokines and soluble factors involved in its production. To gain insight into the mechanisms of age related incidence of onset of allergic symptoms, as well as their severity, in this study we have evaluated in a sample of young (12 females and 15 males, range 20-64 years) and old (42 females and 20, males range 70-93 years) individuals serum values of IgE and sCD23 and in vitro Type 2 cytokine production. Total serum IgE levels were quantified by CAP-system fluorescence enzyme immunoassay. Serum CD23 levels were measured by a sandwich enzyme-linked immunoassay. Enzyme immunoassay tests have been used to quantify IL-4, IL-10 and IL-13 on mitogen-stimulated cultures. Serum total IgE and sCD23 in the two groups of young and old subjects were not significantly different. No detectable levels of IL-4, IL-10 and IL-13 were observed in supernatants from unstimulated cultures in all the subjects tested. After 48 h stimulation with PHA, cytokine amounts became detectable in all subjects. However, the values of the cytokines under study were not significantly different between young and old subjects. In our study, we have not been able to show no impairment in the afferent (type 2 cytokine production) and in the central (serum IgE and sCD23 levels) branch of allergic responses. Previous studies have shown that the efferent branch, at least studied as basophil releasability and bronchial responsiveness, is not impaired in elderly. In conclusion, as suggested from the present and previous papers it is questionable whether there is sufficient information to validate the statement that the incidence of allergic diseases decreases with age. 相似文献