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Onelio Geatti Brahm Shapiro Pier Giuseppe Orsolon Gianni Proto Ugo Paolo Guerra Francesco Antonucci Daniele Gasparini 《European journal of nuclear medicine and molecular imaging》1994,21(1):17-22
Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial). 相似文献
3.
Cipriano C Giacconi R Muzzioli M Gasparini N Orlando F Corradi A Cabassi E Mocchegiani E 《Mechanisms of ageing and development》2003,124(8-9):877-886
Because of its similarity to ageing in impaired immune efficiency 48 h after surgical procedures on young partially hepatectomised mice, partial hepatectomy/liver regeneration (pHx) provides a good model for the study of inflammation in ageing. In old age, high metallothionein (I+II) (MT) sequesters a substantial number of intracellular zinc ions consequently leading to low zinc ion bioavailability for an adequate immune response. Corticosterone and IL-6 affect MTmRNA induction in inflammation and after pHx against oxidative damage. The aim of this study was to investigate the role played by MT in conferring immune plasticity in ageing and in very old age using the pHx model. 48 h after their partial hepatectomy, the crude zinc balance was negative in young, old and very old mice coupled with increased MT, corticosterone, sIL-6R and IL-6. Concomitantly, Natural Killer (NK) cell activity and IL-2 production decreased. Complete restoration of the nutritional-endocrine-immune parameters occurred 15 days from the surgical procedures in young and very old mice, but not in old or transgenic mice overexpressing MT. A significant positive or inverse correlation among nutritional-endocrine-immune parameters exists in young and very old mice, but not in old mice during liver regeneration. Since MT also affects c-myc, the gene expression of c-myc declines from 48 h to days 7 and 15 after pHx in young and very old mice, but remains constantly high in old pHx mice for the same days. This circumstance leads to the appearance of tumours in the long run in old pHx mice and survival times that are shorter than old sham controls. Because complete remodelling also occurs in IL-6 and in sIL-6R in very old mice during liver regeneration, the pre-existing inflammation is not detrimental in very old age. As such, very old mice are still responsive to large inflammation, such as pHx, thanks to correct MT homeostasis. Correct MT homeostasis, via c-myc, is therefore pivotal in both suitable liver regeneration and in conferring immune plasticity with subsequent successful ageing. High MT plays an extremely harmful role in ageing: on one hand it lowers zinc ion bioavailability levels required for immune efficiency and on the other hand it increases c-myc expression. The combination of immune depression and enhanced c-myc, via high MT, may trigger the appearance of age-related degenerative diseases. 相似文献
4.
Ansaldi F Bacilieri S Amicizia D Valle L Banfi F Durando P Sticchi L Gasparini R Icardi G Crovari P 《Journal of medical virology》2004,74(1):141-146
Although the haemagglutination inhibition assay is considered the "gold standard" for antigenic characterisation of influenza viruses, some limitations of this technique are well known. A new microneutralisation assay, as a tool for antigenic characterisation of influenza B viruses, has been standardised and its performance evaluated in comparison with the haemagglutination inhibition test in the light of molecular characterisation of the haemagglutinin. Twelve B viruses belonging to the two lineages and the four sub-lineages discriminated by phylogenetic analysis of HA were tested. The microneutralisation assay clearly distinguishes viruses belonging to different lineages and, in addition, discriminates strains belonging to different sub-lineages that are poorly or not discriminated using the haemagglutination inhibition test. This new microneutralisation assay could provide a useful tool for antigenic characterisation of circulating influenza viruses and contribute, together with the haemagglutination inhibition test and sequence analysis of the haemagglutinin and neuraminidase, in the choice of the strain for use in vaccine composition. 相似文献
5.
Enterotoxicity and cytotoxicity of Vibrio parahaemolyticus thermostable direct hemolysin in in vitro systems 总被引:5,自引:0,他引:5 下载免费PDF全文
Raimondi F Kao JP Fiorentini C Fabbri A Donelli G Gasparini N Rubino A Fasano A 《Infection and immunity》2000,68(6):3180-3185
Vibrio parahaemolyticus is a marine bacterium known to be a common cause of seafood gastroenteritis worldwide. The thermostable direct hemolysin (TDH) has been proposed to be a major virulence factor of V. parahaemolyticus. TDH causes intestinal fluid secretion as well as cytotoxicity in a variety of cell types. In this study, we investigated the interplay between the hemolysin's enterotoxic and cytotoxic effects by using both human and rat cell monolayers. As revealed by microspectrofluorimetry, the toxin causes a dose-dependent increase in intracellular free calcium in both Caco-2 and IEC-6 cells. This effect was reversible only when low toxin concentrations were tested. The TDH-activated ion influx pathway is not selective for calcium but admits ions such sodium and manganese as well. Furthermore, in the same range of concentration, the hemolysin triggers a calcium-dependent chloride secretion. At high concentrations, TDH induces a dose-dependent but calcium-independent cell death as assessed by functional, biochemical, and morphological assays. 相似文献
6.
Guido Grappiolo Carmine F. Bruno Mattia Loppini Michele Mercurio Davide Castioni Giorgio Gasparini Olimpio Galasso 《The Journal of arthroplasty》2021,36(3):1060-1066
BackgroundDespite promising results at the mid-term followup, several aspects of conversion of the fused hip to total hip arthroplasty (THA) remain controversial. The aim of this study was to evaluate clinical and radiological outcomes with a minimum 5-year followup in patients who underwent conversion of the fused hip to THA.MethodsFifty-seven patients (59 hips) were evaluated. The Harris Hip Score (HHS), range of motion (ROM), and the Visual Analogue Scale (VAS) were used to assess hip function and low back pain. Subjective satisfaction with surgery and the presence of the Trendelenburg sign was also evaluated. Radiological assessment was performed pre- and postoperatively to evaluate loosening and heterotopic ossification (HO).ResultsAfter a mean followup of 13.0 ± 6.2 years, HHS and VAS significantly improved from 46.0 ± 16.7 to 80.8 ± 18.8 and from 4.4 ± 1.5 to 2.1 ± 1.4 (both P < .001), respectively. Twenty-three patients (40.4%) had a positive Trendelenburg sign, and HOs were found in 29 cases (49.1%). An overall 29.8% complication rate was noted. Smoking habits and rheumatoid arthritis were predictive of Trendelenburg sign (P = .046 and P = .038, respectively). Implant survival rate as the end point was 98.7 ± 1.3% at 5 years, 92.4 ± 3.3% at 10 years, 82.1 ± 5.7% at 15 years, and 73.4 ± 8.0% at 20 and 25 years. A worse cumulative implant survival rate was noted in patients who underwent previous hip surgery, defined as any hip operation before fusion (P = .005).ConclusionConversion of the fused hip to hip arthroplasty provides high levels of hip functionality and satisfaction with surgery at long-term followup. An implant survival rate higher than 70% can be expected 25 years postoperatively. 相似文献
7.
M. Gasparini S. Khan J. M. Patel D. Parekh M. N. Bangash R. Stϋmpfle A. Shah B. Baharlo S. Soni Collaborators 《Anaesthesia》2021,76(3):320-326
Renal impairment is common in patients who are critically ill with coronavirus disease-19 (COVID-19). We examined the association between acute and chronic kidney disease with clinical outcomes in 372 patients with coronavirus disease-19 admitted to four regional intensive care units between 10 March 2020 and 31 July 2020. A total of 216 (58%) patients presented with COVID-19 and renal impairment. Acute kidney injury and/or chronic kidney disease was associated with greater in-hospital mortality compared with patients with preserved renal function (107/216 patients (50%) (95%CI 44–57) vs. 32/156 (21%) (95%CI 15–28), respectively; p < 0.001, relative risk 2.4 (95%CI 1.7–3.4)). Mortality was greatest in patients with renal transplants (6/7 patients (86%) (95%CI 47–100)). Mortality rates increased in patients with worsening renal injury according to the Kidney Disease: Improving Global Outcomes classification: stage 0 mortality 33/157 patients (21%) (95%CI 15–28) vs. stages 1–3 mortality 91/186 patients (49%) (95%CI 42–56); p < 0.001, relative risk 2.3 (95%CI 1.7–3.3). Survivors were less likely to require renal replacement therapy compared with non-survivors (57/233 patients (24%) vs. 64/139 patients (46%), respectively; p < 0.001, relative risk 1.9 (95%CI 1.4–2.5)). One-fifth of survivors who required renal replacement therapy acutely in intensive care continued to require renal support following discharge. Our data demonstrate that renal impairment in patients admitted to intensive care with COVID-19 is common and is associated with a high mortality and requirement for on-going renal support after discharge from critical care. Our findings have important implications for future pandemic planning in this patient cohort. 相似文献
8.
Gasparini G Testolin A Maluta S Cristoferi V Pozza F 《International journal of oncology》1993,2(2):185-190
Several phase II studies have shown that concurrent chemotherapy and radiotherapy (RT) improves the response rates and locoregional control in patients with advanced, unresectable squamous-cell carcinoma of the head and neck (H&N). However, it is still unclear which is the drug of choice to be given with RT. We therefore conducted a randomized comparison of cisplatin (CDDP)-RT versus carboplatin (CRP)-RT in such patients. The two platinum compounds were given at equitoxic doses. The primary objective of the study was to compare the side effects and the response rates of the two regimens. Radiotherapy was given at conventional dosages, 2 Gy for 5 days every week for a total dose of 64 Gy with CDDP 80 mg/m2 or CRP 375 mg/m2 for three cycles on days 1, 21 and 42. At present 53 patients are entered in the study: 27 in the CDDP arm and 26 in the CRP. The two arms were balanced for all the pre-treatment characteristics. Both the schedules were well tolerated. However, incidence of nausea and vomiting (p=0.0045); anemia (p=0.032) and peripheral neuropathy (p=0.032) was significantly greater with CDDP-RT as compared to CRP-RT. On the other hand, CRP-RT gives a significantly higher incidence of stomatitis (p=0.0067) and a marginally worse thrombocytopenia (p=0.09). The complete response (CR) rates were similar in the two arms (55.5% in the CDDP-RT versus 61.5% in that CRP-RT, respectively) as well as the overall response rates (92.5% versus 84.5%, respectively; p=0.36). The estimated 1 -and 2 year overall and disease-free survival rates were not significantly different in the two arms. In both the groups logistic-regression models showed that those patients with a CR (p=0.017); stage III (p=0.011); smaller primary (p=0.025) and limited node-involvement (p<0.001) had a significant better survival. We conclude that concurrent chemo-radiotherapy is an effective and safe treatment for patients with locally advanced H&N cancer. The combination CRP-RT possess a similar activity but a different, and perhaps a more favorable, spectrum of toxicity when compared to the CDDP-RT therapy. Survival results need to be assessed in a larger series and followed for a more prolonged time. 相似文献
9.
Cathepsin D is a lysosomal aspartyl protease which seems to be involved in invasiveness and metastasis in breast carcinoma. Cathepsin D expression detected by immunocytochemistry is a new potentially useful prognostic marker. Additional research is warranted because: (i) few immunocytochemical studies have been performed to correlate cathepsin D expression and prognosis; (ii) a consensus has not yet been achieved on methodology and quality control issues; (iii) the association between cathepsin D expression and other new biological markers is poorly known and (iv) few studies have assessed whether cathepsin D expression is an independent prognostic marker when compared with other biological and clinico-pathological features using multivariate analysis. This study was undertaken in the same series of 165 stage I-II breast cancer patients (median follow-up of 5 years) already reported (Int J Oncol 4: 155-162, 1994) in whom cathepsin D was assessed using the D7E3 monoclonal antibody by immunocytochemistry in frozen specimens, using a standard peroxidase-antiperoxidase complex method. Cathepsin D was compared with another 7 biological markers, as well as with the conventional clinico-pathological features. Forty-two carcinomas of the 165 analyzed (25.5%) were cathepsin D-positive. This marker was significantly associated with c-erbB-2 expression (p=0.004) and tumour vascularization (p=0.02). Yet, a weak association was observed between cathepsin D and S-phase fraction (p=0.06). In univariate analysis cathepsin D was significantly associated both with relapse-free survival (p<0.01) and overall survival (p=0.02). In multivariate analysis, for relapse-free survival the variables cathepsin D/tumour vascularization, as well as S-phase fraction and EGFR, were significant and independent. For overall survival the variables cathepsin D/c-erbB-2 protein, as well as tumour vascularization and S-phase fraction were significant and independent. Immunocytochemical determination of cathepsin D, using the D7E3 antibody, seems to be a useful prognostic tool in early-stage breast cancer. In particular, cathepsin D adds prognostic information to tumour vascularization (in predicting relapse-free survival) and to c-erbB-2 expression (in predicting overall survival). 相似文献
10.
Brusaferro S Barbone F Andrian P Brianti G Ciccone L Furlan A Gnesutta D Stel S Zamparo E Toniutto P Ferroni P Gasparini V 《European journal of epidemiology》1999,15(2):125-132
Background/aims: To understand the intrafamilial transmission and the existing risk factors related to HCV infection in subjects confirmed anti-HCV positive, their sexual partners and household contacts in Friuli, North-East Italy. Methods: We enrolled all the subjects that were consecutively identified as HCV positive during routine laboratory testing in six health districts and their household contacts. From each subject we obtained a blood sample, demographic data and a medical history including the existence of risk factors for HCV. Antibodies to HCV were detected employing a commercially available second-generation enzyme immunoassay (EIA); positive serum specimens were retested using a second-generation recombinant immunoblot assay (RIBA-2). Results: We recruited 743 subjects, 229 first subjects identified as HCV positive and 514 household contacts. There were no statistically significant differences in positivity among household contacts. Analysing intracouple transmission we found no significant differences by gender in couples both with and without parenteral risk factors. We found, both with univariate and multivariate analysis, as statistically significant risk factors in all the subjects: age older than 60, blood transfusions (particularly those performed before 1984), surgical procedures such as abortion and/or uterine curettage, history of HBV infection, intravenous drug use, and tattooing. Conclusions: Our results stress the low relevance of sexual transmission in the intrafamilial context, the importance of abortion and/or uterine curettage, the important role of blood transfusions in the past, a higher prevalence of HCV infection within a household of a HCV positive member compared to all other existing data in the area. 相似文献