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71.
Ottavio Cavicchi Ottavio Piccin Umberto Caliceti Angelo De Cataldis Renato Pasquali Alberto Rinaldi Ceroni 《Otolaryngology--head and neck surgery》2007,137(4):654-658
OBJECTIVE: The purpose of this study was to identify the risk factors for postoperative transient hypoparathyroidism in a group of patients undergoing thyroid surgery. STUDY DESIGN: A prospective study was conducted on 604 patients undergoing thyroid surgery. SUBJECTS AND METHODS: Gender, final diagnosis, extent of resection, biology of pathology, intrathoracic involvement, surgery for recurrent multinodular goiter, and presence and number of parathyroid glands in a surgical specimen were analyzed as risk factors for postoperative transient hypoparathyroidism. The chi-square test and a logistic regression analysis were applied. RESULTS: On logistic regression analysis, only the extent of surgery constituted an independent variable for transient hypoparathyroidism (P = 0.001). CONCLUSION: The extent of surgery to central and/or lateral neck lymph nodes is responsible for a high rate of transient hypoparathyroidism owing to a high probability of unplanned parathyroidectomy or parathyroid gland devascularization. 相似文献
72.
Suppressor response in lepromatous leprosy patients: role of Leu 2a cells. 总被引:2,自引:0,他引:2 下载免费PDF全文
M del Carmen Sasiain S de la Barrera B Ruibal-Ares J E Cardama J C Gatti M M de Bracco 《Immunology》1987,60(1):13-18
The contribution of non-specific suppressor mechanisms to the overall immunoregulatory defect observed in lepromatous leprosy was evaluated. Con A-induced suppression was assayed using the standard two-stage test in 27 lepromatous leprosy patients, 19 of them during the quiescent stage (LL) and eight during erythema nodosum lepromatosum (ENL). Lymphocytes from normal individuals react in this assay, yielding higher suppression as the numbers of Con A-induced suppressor cells (Leu 2a+ cells) increase. In contrast, two patterns of response were observed in both LL and ENL patients: those giving lower suppression as the number of suppressor cells increased (LL-A and ENL-A) and those responding with the normal pattern (LL-B and ENL-B). The abnormal dose-response profile was not related to the disease stage, as both ENL and LL patients were included in groups with normal or atypical response. Reaction of the potential suppressor cells with anti-Leu 2a antibody abolished suppression in LL-B and normals, whereas Con A-induced suppression was unchanged or higher in ENL-A, ENL-B and LL-A, indicating that in these patients Leu 2a+ cells interfered with the generation of Con A-induced suppression. The contribution of spontaneous suppression was examined and it was shown that suppressor activity in the absence of Con A stimulus was higher in ENL (both ENL-A and ENL-B) and LL-A. Thus, it appears that the occurrence of high spontaneous suppressor activity, probably related to in vivo activation, is associated with a relative inability to generate de novo suppression after Con A stimulation in these patients. 相似文献
73.
74.
Simone Maurea Alberto Cuocolo Leonardo Pace Emanuele Nicolai Antonio Nappi Massimo Imbriaco Carmine Morisco Massimo Chiariello Bruno Trimarco Marco Salvatore 《European journal of nuclear medicine and molecular imaging》1993,20(6):502-510
To compare rest-injected thallium-201 (Tl) redistribution and resting technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial uptake in chronic coronary artery disease (CAD), 15 patients with angiographically proven CAD and left ventricular (LV) dysfunction (ejection fraction 34%±9%) were studied. All patients underwent rest-redistribution Tl and resting 99mTc-MIBI cardiac imaging. Gated 99mTc-MIBI images were also acquired to assess regional LV wall motion (WM). Myocardial segments (n=225) were divided into three groups on the basis of the degree of coronary artery stenosis: group 1 (total occlusion, n=82), group 2 (50%–99% of stenosis, n=84) and group 3 (<50% of stenosis, n=59). WM was significantly worse in groups 1 and 2 compared to group 3 (P<0.001), but no difference was observed between groups 1 and 2. TI and 99mTc-MIBI uptake were significantly lower in groups 1 and 2 compared to group 3 (P < 0.001), and in group 1 compared to group 2 (P<0.001). When TI and 99mTc-MIBI uptake were directly compared, TI uptake was higher than 99mTc-MIBI uptake in group 1 (P<0.001), while no significant difference was observed in groups 2 and 3. Thus, both rest-injected TI redistribution and resting 99mTc-MIBI uptake reflected the severity of coronary artery stenosis in CAD. However, in myocardial segments with total coronary occlusion T1 uptake was significantly higher than 99mTc-MIBI uptake. Our data suggest that rest-injected Tl redistribution cardiac imaging may identify, more accurately than resting 99mTc-MIBI imaging, the presence of viable myocardium in chronic CAD, particularly when the coronary blood flow is severely impaired. 相似文献
75.
Carlo Alberto Maggi Riccardo Patacchini Paolo Santicioli Sandro Giuliani Damiano Turini Gabriele Barbanti Patrizia Beneforti Daniele Misuri Alberto Meli 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(4):415-423
Summary (1) Longitudinal muscle strips from the human small intestine (jejunum/ileum) responded to electrical field stimulation (1–50 Hz) with frequency-related primary contractions which were largely atropine- (3 M) sensitive. When the tone was raised by addition of galanin (0.3 – 1 M), prostaglandin (PG) E2 (1–10 M) or neurokinin A (NKA, 0.1 M), a frequency-related relaxation was evident which was potentiated by atropine. All the responses to field stimulation were abolished by tetrodotoxin (1 M), thus indicating their neural origin. (2) The atropine-sensitive primary contraction to field stimulation was virtually abolished by omega conotoxin fraction GVIA (CTX, 0.1–0.3 M) while the relaxations were CTX-resistant. The field stimulation-induced relaxations, which were observed in the presence of atropine and guanethidine (3 M), were also unaffected by apamin (0.1 M). (3) NKA and substance P (SP) produced a concentration- (1 nM–1 M for both peptides) related contraction, NKA being about 53 times more potent than SP. [Pro9]SP sulphone and [MePhe7]-NKB, selective agonists of the NK-1 and NK-3 receptor, respectively, were barely effective. On the other hand, [\Ala8]NKA(4–10), a selective NK-2 receptor agonist, had a potent contractile activity, similar to that of NKA. (4) Galanin (1 nM–1M) produced an atropine- and tetrodotoxin-resistant concentration-related contraction of longitudinal muscle of human isolated small intestine. The response to galanin did not show any sign of fading and was particularly suitable to study the evoked relaxations. (5) Calcitonin gene-related peptide (CGRP) (10–100 nM) consistently inhibited the nerve-mediated contractions of strips from the ileum while the effect on the jejunum was less pronounced. Vasoactive intestinal polypeptide (VIP, 0.1–1 M) inhibited nerve-mediated contractions both in the ileum and the jejunum. (6) These experiments indicate that both cholinergic excitatory and non-adrenergic non-cholinergic nerves affect motility of the longitudinal muscle of the human small intestine. Furthermore, several neuropeptides produce potent motor effects, the contractile response to tachykinins being apparently mediated by activation of NK-2 receptors. 相似文献
76.
Enhanced metabolic activation of chemical hepatocarcinogens in woodchucks infected with hepatitis B virus 总被引:2,自引:0,他引:2
De Flora Silvio; Heitanen Eino; Bartsch Helmut; Camoirano Anna; Izzotti Alberto; Bagnazco Maria; Millman Irving 《Carcinogenesis》1989,10(6):1099-1106
The metabolism of chemical carcinogens was investigated in liverpreparations from 28 captive woodchucks (Marmotamonax). Of these,23 were naturally infected with the wood-chuck hepatitis virus(WHV), and eight also had primary hepatocellular carcinoma (PHC).Twenty-nine parameters were investigated in liver subcelhilarfractions, including cross-reactivity with HBsAg, and biochemicalparameters, such as -glutamyl transpeptidase, cytochrome P-450and mirosomal monooxygenases (aryl hydrocarbon hydroxylase,ethodycoumarin and ethoxyresorufin deethylases, amino-pyrineand dimethylnitrosamine demethylases, and testosterone 7-and16ß- and 6ß-hydroxylases), uridine 5'-diphos-phoglucuronosyltransferase, GSH and related enzymes (peroxidase, reductaseand S-transferase), as well as other cytosolic enzyme activities(glucose 6-phosphate and 6-phosphogluconate dehydrogenases,NADPH- and NADH-dependent diaphorases, and DT diaphorase). Inaddition, liver preparations were used in order to quantifythe metabolic activation into bacterial mutagens of five procarcinogens(aflatoxin B1, the pyrolysis products Trp-P-2 and MelQ, 2-aminofluoreneand dimethylnitrosamine) and the decrease of potency of threedirect-acting mutagens (sodium di-chromate, ICR 191 and 4-nitroquinoline1-oxide). WHV infection produced a significant stimulation ofcarcinogen metabolism, as shown by the simultaneous change indetoxification parameters (GSH depletion) and activation indices(enhancement of microsomal monooxygenases and of pro-carcinogenactivation into mutagenic metabolites). There were no significantdifferences between WHV-positive samples from animals, withoutPHC and the noncancerous tissue of PHC-bearing animals, whereasa decrease of both activation and detoxification indices wasrecorded in the turmorous tissue. There was a considerable interindividualvariability among WHV carriers, which was tentatively ascribedto genetic factors. Pregnancy was the only known factor influencingthe results in WHV carriers. However, even by excluding pregnantanimals, the effects on carcinogen metabolism produced by WHVinfection were still statistically significant. These results,together with previous data obtained in humans, revealed thatmetabolic factors may play a role in the synergism between viralhepatitis and chemical hepato-carcinogens in the etiopathogenesisof PHC. 相似文献
77.
Casanelles Mdel C Gil-Fernández JJ Casero LF Bengoechea MG Serrano R Rañada JM Jurado LA 《American journal of medical genetics. Part A》2003,(4):372-376
Williams or Williams-Beuren syndrome (WBS) is a developmental disorder with multisystemic manifestations characterized by distinctive facial features, mental disability with unique cognitive and personality profiles, vascular stenoses, growth retardation, and occasional infantile hypercalcemia, caused by haploinsufficiency for genes deleted in chromosome band 7q11.23. However, with the exception of arterial stenoses caused by haploinsufficiency for the elastin gene (ELN), no specific implication of any other gene in the phenotype has been established. We present two patients with portal hypertension leading to splenomegaly and pancytopenia carrying the common 1.5 Mb WBS deletion. We propose this is an additional severe vascular complication of ELN deficiency and discuss the specific characteristics of the portal venous tract that could explain the impact of ELN deficiency in that venous territory. This complication is potentially lethal and should thus be considered in any patient with WBS and splenomegaly. 相似文献
78.
López JA Bioley G Turtle CJ Pinzón-Charry A Ho CS Vuckovic S Crosbie G Gilleece M Jackson DC Munster D Hart DN 《Journal of immunological methods》2003,274(1-2):47-61
Dendritic cells (DC) for cancer immunotherapy protocols are generated most commonly by in vitro differentiation of monocytes with exogenous cytokines (Mo-DC). However, Mo-DC differ in their molecular phenotype and function from blood DC (BDC). Clinical isolation of BDC has been limited to the use of density gradients, which result in low yields of variable purity. We have developed a DC enrichment platform, which uses the CMRF-44 (IgM) or CMRF-56 (IgG) monoclonal antibodies (mAb) to select BDC that express these antigens after a short overnight incubation. After culture of peripheral blood mononuclear cells (PBMC) in autologous/AB serum, biotinylated CMRF-44 was used to select DC in a single step immuno-magnetic bead procedure; this produced populations containing up to 99% CMRF-44(+) cells, including up to 67% CMRF-44(+) CD14(-) CD19(-) DC, from an initial starting population of approximately 0.5%. We observed consistent differences in the purities obtained from individual donors with a mean of 54% CMRF-44(+) cells (range 19-99%). Similar results were obtained using biotinylated CMRF-56 mAb, an antibody identifying a comparable population in cultured PBMC. We recovered an average of 54% and 66% of the available BDC in separations performed with the CMRF-44 and CMRF-56 mAb, respectively. The reproducibility of the procedure and the ability to perform it in a closed sterile system makes it suitable for clinical use. Larger scale preparations starting from apheresis derived PBMC will produce sufficient BDC for immunotherapy protocols. The purified BDC elicited strong allogeneic mixed leukocyte reactions and HLA classes II- and I-restricted antigen-specific primary immune responses. 相似文献
79.
Alberto Bacchi-Modena Pierfrancesco Bolis Carlo Campagnoli Fiorenzo De Cicco Michele Meschia Francesco Pansini Roberto Pisati Gabriele Hüls 《Maturitas》1997,27(3):285-292
Objectives: To assess the efficacy and tolerability of a new matrix patch delivering 0.05 mg estradiol per day (Estraderm MX 50) in postmenopausal women with moderate to severe postmenopausal symptoms. Methods: A multicenter, double-blin, randomized, between-patient, placebo controlled trial in 109 postmenopausal women was carried out. Patches were applied twice weekly for 12 weeks. Patients were assessed at 4, 8 and 12 weeks of treatment. The primary efficacy variable was change from baseline in mean number of moderate to severe hot flushes (including night sweats) per 24 h during the last 2 weeks of treatment. Other variables included Kupperman Index, local and systemic tolerability. Plasma concentrations of estradiol (E2), estrone (E1) and estrone sulfate (E1S) were determined before and after treatment. Results: Estraderm MX was significantly superior to placebo (P < 0.001) in reducing mean number of moderate to severe hot flushes (including night sweats) per 24 h after 4, 8 and 12 weeks of treatment. The estimate of treatment group differences after 12 weeks was 4.2 hot flushes (95% confidence interval: 2.6–5.5). Estraderm MX also significantly reduced Kupperman Index at all time points compared to placebo (P < 0.001). Estraderm MX induced increases in mean E2, E1 and E1S plasma levels as expected (E2: baseline 2.7 pg/ml, 12 weeks 38.9 pg/ml; E1: baseline 18.8 pg/ml, 12 weeks 41.6 pg/ml; E1S: baseline 235.6 pg/ml, 12 weeks 765.1 pg/ml). Overall rates of adverse experiences were similar for Estraderm MX and placebo. The number of patients reporting skin irritation was low and similar in both groups. Conclusions: Estraderm MX 50, a new matrix patch, offers an effective and well tolerated dosage form for transdermal delivery of 0.05 mg E2 per day. 相似文献
80.
Evaluation of stromal metalloproteinases and vascular endothelial growth factors in a spontaneous metastasis model 总被引:5,自引:0,他引:5
Donadio AC Durand S Remedi MM Frede S Ceschin DG Genti-Raimondi S Chiabrando GA 《Experimental and molecular pathology》2005,79(3):259-264
This study aims to investigate MMP2 and MT1-MMP protein as well as VEGF-C and VEGF-D mRNA expression in tumor cells and distant organs considered to be targets for metastasis in a tumor spontaneous metastasis model previously described. Cultured tumor cells, able to express pro-MMP2, MMP2, pro-MMP9, and MT1-MMP, develop tumor growth and metastasis, mainly in the liver and spleen, when they are injected in the mammary pad gland of Wistar rats. Immunohistochemical studies of tumor masses showed small groups of tumor cells staining for MT1-MMP but not for MMP2. In the liver, tumor metastatic foci and a stromal positive staining for both MMP2 and MT1-MMP were shown. The spleen and lymph nodes, with only scattered metastatic cells, did not show MMPs immunostaining. Using RT-PCR, a significantly higher VEGF-C and VEGF-D gene expression was shown in the liver of tumor-bearing rats respect to normal rats, whereas spleen and lymph nodes did not show significant differences in mRNA VEGF-C/D levels. Taken together, our results suggest that the stroma microenvironment of target organs for metastasis has the ability to produce MMPs and VEGFs that facilitate the anchorage of tumor cells and promote tumor cell growth and angiogenesis. 相似文献