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81.
Elena Menegola Francesca Di Renzo Francesca Metruccio Angelo Moretto Erminio Giavini 《Archives of toxicology》2013,87(11):1989-1997
The effect of mixtures of azole fungicides on development of postimplantation rat whole-embryos cultured in vitro has been tested. On the basis of bench mark dose (BMD) modeling of the in vitro effect in rat embryo, the potency of 7 azoles was determined and compared. Then, relative potency factors have been derived based on either the NOAEL or on the BMD curve. Alternatively, each compound was used as index compound (IC), and IC-equivalent concentrations have been calculated for each mixture. Expected effects of such IC-equivalent concentrations of the mixture were derived from the appropriate BMD curve. Test mixture includes the agrochemicals triadimefon and imazalil (MIX2) or triadimefon, imazalil, and the clinically used fluconazole (MIX3) at their previously determined no-effect concentration, corresponding to approximately a benchmark response of 5–10 %. Subsequently, we tested the effect of a mixture of the agrochemicals triadimefon, imazalil, triadimenol, cyproconazole, tebuconazole, and flusilazole (MIX6) at concentration levels derived from their established human acceptable daily intake. MIX6 was also added with fluconazole at concentration levels indicated as the minimum therapeutically effective plasmatic concentration (MIX7A) or ten times this level (MIX7B). Generally, the experimental response was higher than the estimated one, by a factor of 2–6. Our data suggest that it is in principle correct to assume that azoles act as teratogens via a common mode of action and therefore should be grouped together for risk assessment. The synergistic effect needs to be confirmed with more combinations of concentrations/compounds in vitro and with specific in vivo experiments. 相似文献
82.
The outcome of operations performed in different institutions or by different surgeons can hardly be compared if the operative methods are not standardized. Six different vaginal hysterectomy methods were studied. The steps common in all of them were defined. These steps were analyzed for optimal performance and sequence during the operation. The resultant modified method was subjected to a prospective randomized study, which showed that the operation time and the need for pain drugs were reduced. This method was introduced to several departments in different countries. The optimization and standardization of surgical methods are expected not just to improve the postoperative outcome, but also to enable a comparison between different departments and surgeons. 相似文献
83.
Raymond E. Goldstein H. Keith Moffatt Adriana I. Pesci Renzo L. Ricca 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(51):21979-21984
It is well-known that a soap film spanning a looped wire can have the topology of a Möbius strip and that deformations of the wire can induce a transformation to a two-sided film, but the process by which this transformation is achieved has remained unknown. Experimental studies presented here show that this process consists of a collapse of the film toward the boundary that produces a previously unrecognized finite-time twist singularity that changes the linking number of the film’s Plateau border and the centerline of the wire. We conjecture that it is a general feature of this type of transition that the singularity always occurs at the surface boundary. The change in linking number is shown to be a consequence of a viscous reconnection of the Plateau border at the moment of the singularity. High-speed imaging of the collapse dynamics of the film’s throat, similar to that of the central opening of a catenoid, reveals a crossover between two power laws. Far from the singularity, it is suggested that the collapse is controlled by dissipation within the fluid film surrounding the wire, whereas closer to the transition the power law has the classical form arising from a balance between air inertia and surface tension. Analytical and numerical studies of minimal surfaces and ruled surfaces are used to gain insight into the energetics underlying the transition and the twisted geometry in the neighborhood of the singularity. A number of challenging mathematical questions arising from these observations are posed. 相似文献
84.
Laura Di Renzo Annalisa Noce Sandro De Angelis Natascia Miani Nicola Di Daniele Carmela Tozzo Antonino De Lorenzo 《Pharmacological research》2008,57(2):93-99
Low-grade inflammation is a common feature of chronic kidney disease (CKD) and persistent systemic inflammation is thought to be a strong predictor of cardiovascular events. Inflammation plays a role in determining the serum albumin levels in haemodialysis patients (HD) independently of the nutritional status. Increased cardiovascular mortality in CKD has been associated with the increased incidence of obesity in uremic patients. Ingenbleek suggested a prognostic inflammation and nutritional index (PINI), based on serum albumin, pre-albumin, C-reactive protein, and alpha1 acid glycoprotein, to identify and to follow up acutely ill patients at risk of major complications. The aims of the present study were: to verify the incidence of Normal Weight Obese (NWO) syndrome; to evaluate by PINI the effect of 8 weeks acetyl salicylic (100 mg/die) and atorvastatin (10 mg/die) combined treatment on chronic inflammation in 52 selected HD patients. Laboratory evaluation, anthropometric and body composition measurements were detected. At baseline the 56.25% of non-obese, the 84.21% of pre-obese-obese, and the 41.17% of NWO women showed PINI values >1 (normal status PINI<1). After the pharmacological treatment, high significant (P<0.001) reduction in lipid profile, an elevated increase of HDL levels, and a significant reduction of inflammatory markers were obtained. Firstly, our results showed that ASA and atorvastatin combined treatment was effective in reducing inflammatory status in HD patients independently of body composition: at the end of the study only 7.49% of the patients exhibited PINI>1. Further studies will be necessary to understand the causes of inflammation in non-responder patients. 相似文献
85.
New pansomatostatin ligands and their chelated versions: affinity profile, agonist activity, internalization, and tumor targeting. 总被引:1,自引:0,他引:1
Mihaela Ginj Hanwen Zhang Klaus-Peter Eisenwiener Damian Wild Stefan Schulz Hans Rink Renzo Cescato Jean Claude Reubi Helmut R Maecke 《Clinical cancer research》2008,14(7):2019-2027
PURPOSE: Somatostatin receptor (sst) targeting is an established method to image and treat sst-positive tumors. Particularly, neuroendocrine tumors express the receptor subtype 2 in high density, but sst1, sst3, sst4, and sst5 are also expressed to some extent in different human tumors. Currently used targeting peptides mainly have sst2 affinity. We aimed at developing (radio)peptides that bind with high affinity to all receptor subtypes. EXPERIMENTAL DESIGN: Carbocyclic octapeptides were coupled with macrocyclic chelators for radiometal labeling. Affinity, internalization, and agonist potencies were determined on sst1- to sst5-expressing cell lines. Biodistribution was determined on nude mice bearing HEK-sst2 or AR4-2J and HEK-sst3 tumors. RESULTS: High affinity to all receptor subtypes was found. Y(III)-KE88 showed agonistic properties at all five sst receptor subtypes as it inhibits forskolin-stimulated cyclic AMP production. Surprisingly, very low or even absent sst2 receptor internalization was found compared with currently clinically established octapeptides, whereas the sst3 internalization was very efficient. Biodistribution studies of [(111)In]KE88 and [(67)Ga]KE88/[(68)Ga]KE88 reflected the in vitro data. In nude mice with s.c. implanted sst2 (HEK-sst2, AR4-2J)-expressing and sst3 (HEK-sst3)-expressing tumors, high and persistent uptake was found in sst3-expressing tumors, whereas the uptake in the sst2-expressing tumors was lower and showed fast washout. The kidney uptake was high but blockable by coinjection of lysine. CONCLUSION: This peptide family shows pansomatostatin potency. As radiopeptides, they are the first to show a full pansomatostatin profile. Despite some drawback, they should be useful for imaging sst2-expressing tumors with short-lived radiometals, such as (68)Ga, at early time points and for sst3-expressing tumors at later time points with longer-lived radiometals, such as (64)Cu or (86)Y. 相似文献
86.
A Barbati M M Anceschi P Alberti G Pomili G C Di Renzo E V Cosmi 《American journal of obstetrics and gynecology》1989,160(2):514-517
CA 125 antigen was measured in amniotic fluid, maternal blood, cord blood, and fetal urine by a commercially available immunoradiometric assay kit. The amniotic fluid was obtained from 99 normal pregnancies at various gestational ages. The mean antigen levels were 29,676, 3350, and 1680 U/ml in amniotic fluid of the first, second, and third trimesters, respectively. In maternal blood, 12.5% of pregnant women in the first trimester of pregnancy showed elevated levels of CA 125 (65 to 100 U/ml). Late in gestation, CA 125 levels in cord blood and fetal urine were always less than 65 U/ml. Immunohistochemical study of CA 125 in fetal membranes, placenta, and decidua showed the presence of antigen only in the amnion. These results suggest that CA 125 is shed into amniotic fluid directly from the amniotic membrane. 相似文献
87.
De Renzo A Persico E de Marino F di Giacomo Russo G Notaro R di Grazia C Picardi M Santoro L Torella R Rotoli B Persico M 《Haematologica》2002,87(7):714-8; discussion 718
BACKGROUND AND OBJECTIVES: During the last decade an epidemiological association between hepatitis C virus (HCV) and B-cell lymphoproliferative disorders (B-LPD) has been reported; the same association has not been observed for Hodgkin's disease (HD). Hepatitis G virus (HGV) shares genetic and biological features with HCV, thus it might also be involved in lymphomagenesis. DESIGN AND METHODS: The aim of this study was to compare the prevalence of HCV and HGV infection in patients at diagnosis of B-LPD or HD. RESULTS: We tested 227 consecutive untransfused patients (127 with B-LPD and 100 with HD) and 110 healthy controls. The prevalence of HCV infection was significantly higher in B-LPD patients than in controls (17.3% vs. 1.8%, p<0.002 ), whereas it was the same in HD patients as in controls. In contrast, the prevalence of HGV was significantly higher in patients, both those with B-LPD (7.8% vs. 0.9%, p<0.03) and those with HD (13% vs. 0.9%, p<0.002), than in controls. Among the various B-LPD tested, HGV infection was more frequent in B-NHL (11.5%). INTERPRETATION AND CONCLUSIONS: Our data support the hypothesis that HGV infection may play a role in lymphomagenesis and that this role is different and separate from that of HCV. 相似文献
88.
Palatini P Malacco E Di SS Carretta R Dorigatti F Bertocchi F Mann J 《European journal of clinical pharmacology》2002,57(11):765-770
OBJECTIVE: The aim of this study was to measure the time-effect profiles of a once-daily administered valsartan/hydrochlorothiazide combination and amlodipine on blood pressure using various indices derived from 24-h ambulatory blood pressure (BP) monitoring. METHODS: Of the 310 randomized outpatients with uncomplicated mild-to-moderate primary hypertension, 259 (133 on valsartan/hydrochlorothiazide, 126 on amlodipine) were eligible for analysis. After a 2-week placebo wash-out period, the patients were randomly allocated to treatment with either valsartan 80 mg once daily (o.d.) or amlodipine 5 mg o.d. for 4 weeks; in the case of an unsatisfactory blood pressure response, the treatments could be respectively changed to the fixed combination of valsartan 80 mg plus hydrochlorothiazide 12.5 mg o.d. or amlodipine 10 mg o.d. for a further 8 weeks. The trough:peak ratio (global and individualized approaches) and smoothness index (i.e., the ratio between the average of the 24-hourly BP changes after treatment and the corresponding standard deviation) were calculated from 24-h ambulatory blood pressure recordings made after the placebo period and after 4 weeks and 12 weeks of active treatment. RESULTS: Both regimens effectively lowered systolic and diastolic ambulatory pressures after 4 weeks and 12 weeks (all P<0.001) but, among the responders, the valsartan/hydrochlorothiazide combination had a greater antihypertensive effect during the night-time hours after 12 weeks (P=0.03/0.02). In the responders, the placebo-adjusted, mean trough:peak ratios were 0.76/0.74 in the valsartan/hydrochlorothiazide group (n = 111) and 0.66/0.62 in the amlodipine group (n = 101). The corresponding global trough:peak ratios were 0.61/0.57 for the valsartan/hydrochlorothiazide combination and 0.56/0.56 for amlodipine. However, the between-group differences in individual or global trough:peak ratios were not significant. The smoothness index was slightly, but insignificantly, greater for valsartan/hydrochlorothiazide than for amlodipine in the responders and the groups as a whole. CONCLUSION: Valsartan/hydrochlorothiazide and amlodipine were equally effective in reducing ambulatory BP, but the valsartan/hydrochlorothiazide combination led to more homogeneous BP control during the inter-dosing interval. Trough:peak ratio and smoothness index did not reflect this finding accurately. 相似文献
89.
90.