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111.
Magnetic resonance imaging of the pituitary gland in patients with secondary hypogonadism due to transfusional hemochromatosis 总被引:1,自引:0,他引:1
Gianvincenzo Sparacia Massimo Midiri Paolo D'Angelo Roberto Lagalla 《Magma (New York, N.Y.)》1999,8(2):87-90
To identify pituitary iron overload in patients with transfusional hemochromatosis causing secondary hypogonadism, we prospectively
evaluated signal intensity abnormalities of the anterior lobe of the pituitary gland of 18 patients affected by transfusion-dependent
thalassemia major and secondary hypogonadism. Magnetic resonance (MR) imaging is useful to assess pituitary iron overload
in patients with transfusional hemochromatosis and secondary hypogonadism by detection of a significant decreased signal intensity
of the anterior lobe of the pituitary gland on GRE T2*-weighted images. The decreased signal intensity of the anterior lobe of the pituitary gland on GRE T2*-weighted images was correlated to increasing serum ferritin level (r=−0.84,r
2=−0.70,P<0.001). Indeed, the lower the signal intensity of the pituitary gland the greater the serum ferritin level. However an exact
quantification of pituitary iron overload by correlation with serum ferritin level is not allowed. No correlation was found
between MR imaging results and hormonal status; however, the detection of pituitary iron overload on GRE T2*-weighted images is consistent with the hypothesis of hypogonadotrophic pituitary insufficiency due to iron-induced cellular
damage. 相似文献
112.
Barbara Faccini Dario Di Giuseppe Giacomo Ferretti Massimo Coltorti Nicolò Colombani Micòl Mastrocicco 《Nutrient Cycling in Agroecosystems》2018,110(2):327-341
In this paper we report an overview of the main outcomes of a 3-years experimental cultivation carried out in an Italian reclaimed agricultural field amended with different types of zeolitites (rock containing > 50% of zeolites), under cereals cultivation (Sorghum vulgare Pers, Zea mays and Triticum durum). The aim of the experiment was to exploit the properties of zeolite-rich volcanic rocks (zeolitites) for reducing the excessively high NO3? content in the soil and in waters flowing out the sub-surface drainage system of the field and flushing into the surface water system, reducing concomitantly also chemical fertilization application rates (up to 50%). Zeolitites were tested both in their natural state and in a NH4+-enriched form, obtained through an enrichment process with NH4+-rich zoo-technical effluents (pig slurry). NO3? content in soils and in waters discharged through SSDS were periodically monitored during the experimentation and crop yield quantified. Results showed that, for three consecutive cultivation cycles, the overall NO3? concentrations in water extracts was reduced by 45% in the zeolitite treated soils, while in SSDS waters the reduction reached the 64%. Notwithstanding the lower N input from chemical fertilizers, crop yield was not negatively affected in the zeolitite amended soils with respect to the control. Zeolitite addition increased thus soil NH4+ retention and probably influenced several pathways of N losses, allowing a better fertilizer use efficiency by plants and a reduction of the overall NO3? concentrations in the surface waters. 相似文献
113.
114.
Roberta D’Ambrosio Alessio Aghemo Raffaele De Francesco Maria Grazia Rumi Enrico Galmozzi Stella De Nicola Cristina Cheroni Paul J. Clark Guido Ronchi Pietro Lampertico Massimo Colombo 《International journal of molecular sciences》2014,15(5):7213-7224
The interleukin 28B (IL28B) rs12979860 polymorphism is associated with treatment outcome in hepatitis C virus (HCV) genotype 1 and 4 patients. Its association with the histological features of chronic hepatitis C and disease severity needs further clarifications. To assess the correlation between IL28B genotype, HCV genotype and liver biopsy findings in untreated patients.
Materials and Methods
Pre-treatment liver biopsies from 335 HCV Caucasian patients (59% males, age 50 years) enrolled in the MIST study were staged for fibrosis and inflammation according to the METAVIR and the Ishak scoring systems; steatosis was dichotomized as <5% or ≥5%. IL28B was typed by Taqman Single Nucleotide Polymorphism (SNP) genotyping assay. HCV genotype was 1 in 151 (45%), 2 in 99 (30%), 3 in 50 (15%) and 4 in 35 (10%) patients. IL28B genotype was CC in 117 (34%), CT in 166 (49%) and TT in 52 (15%). At univariate analysis, the IL28B CC genotype was associated with severe portal inflammation in HCV-1 patients (CC vs. CT/TT: 86% vs. 63%, p = 0.005), severe lobular inflammation in HCV-2 patients (CC vs. CT/TT: 44% vs. 23%, p = 0.03), and less fatty infiltration in HCV-1 patients (CC vs. CT/TT: 72% vs. 51%, p = 0.02). Despite the lack of any association between IL28B and fibrosis stage, in HCV-3 patients IL28B CC correlated with METAVIR F3–F4 (CC vs. CT/TT: 74% vs. 26%, p = 0.05). At multivariate analysis, the genotype CC remained associated with severe portal inflammation in HCV-1, only (Odds Ratio (OR): 95% Confidence Interval (CI): 3.24 (1.23–8.51)). IL28B genotype is associated with the histological features of chronic hepatitis C in a HCV genotype dependent manner, with CC genotype being independently associated with severe portal inflammation. 相似文献115.
Patrizio Raffa Adamantia Kassi Julian Gosschalk Nicola Migliore Lorenzo Massimo Polgar Francesco Picchioni 《大分子材料与工程》2021,306(4):2000755
A series of copolymers of styrene and furfuryl methacrylate characterized by various molecular structures (linear and star, block and random) is synthesized via atom transfer radical polymerization, and cross-linked with a bismaleimide by means of thermally reversible Diels–Alder (DA) reaction, to obtain self-healing materials. The prepared materials are studied in terms of gelation, swelling, thermal, and dynamic-mechanical analysis, with the aim of correlating relevant properties to their chemical structure. It is found that the furan/styrene ratio, as well as the molecular architecture, have a major influence on the properties. It is also found that the reversibility of the DA reaction is not complete in the solid state for materials with high cross-linking density. This study provides some important tools for the design of materials characterized by thermally reversible behavior, which find usually application as self-healing thermosets, coatings, or adhesives. 相似文献
116.
Sabrina Caporali Biagio Didona Mauro Paradisi Alessandro Mauriello Elena Campione Mattia Falconi Federico Iacovelli Marilena Minieri Massimo Pieri Sergio Bernardini Alessandro Terrinoni 《International journal of molecular sciences》2021,22(13)
Palmoplantar keratodermas (PPKs) are characterized by thickness of stratum corneum and epidermal hyperkeratosis localized in palms and soles. PPKs can be epidermolytic (EPPK) or non epidermolytic (NEPPK). Specific mutations of keratin 16 (K16) and keratin 1 (K1) have been associated to EPPK, and NEPPK. Cases of mosaicism in PPKs due to somatic keratin mutations have also been described in scientific literature. We evaluated a patient presenting hyperkeratosis localized monolaterally in the right palmar area, characterized by linear yellowish hyperkeratotic lesions following the Blaschko lines. No other relatives of the patient showed any dermatological disease. Light and confocal histological analysis confirmed the presence of epidermolityic hyperkeratosis. Genetic analysis performed demonstrates the heterozygous deletion :r.274_472del for a total of 198 nucleotides, in KRT1 cDNA obtained by a palmar lesional skin biopsy, corresponding to the protein mutation NM_006121.4:p.Gly71_Gly137del. DNA extracted from peripheral blood lymphocytes did not display the presence of the mutation. These results suggest a somatic mutation causing an alteration in K1 N-terminal variable domain (V1). The deleted sequence involves the ISIS subdomain, containing a lysine residue already described as fundamental for epidermal transglutaminases in the crosslinking of IF cytoskeleton. Moreover, a computational analysis of the wild-type and V1-mutated K1/K10 keratin dimers, suggests an unusual interaction between these keratin filaments. The mutation taster in silico analysis also returned a high probability for a deleterious mutation. These data demonstrate once again the importance of the head domain (V1) of K1 in the formation of a functional keratinocyte cytoskeleton. Moreover, this is a further demonstration of the presence of somatic mutations arising in later stages of the embryogenesis, generating a mosaic phenotype. NP_006112.3相似文献
117.
Massimo Guglielmi Giovanna Brusatin Giacomo Facchin Mario Gleria Roger De Jaeger Marco Musiani 《Journal of Inorganic and Organometallic Polymers》1996,6(3):221-236
In this paper the sol-gel preparation of hybrid materials made of metal oxide and polytorganophosphazenel components is described. The main problem focused on during this research was to avoid phase separation in order to get homogeneous materials. This problem was pursued looking at the formation of genuine chemical bonds between the exploited polyphosphazenes and the inorganic composite networks. Investigations on the thermal, mechanical, and electroconductive properties of the synthesized, phosphazene-containing composite materials showed that these matrices presented improved mechanical and thermal features with respect to those of the original phosphazene macromolecule, while the ionic conductivities of the prepared molecular hybrids doped with lithium or silver trillate are of the same order of magnitude as those measured for the neat, original phosphazene substrate.Presented at the Ist Italian Workshop on Cyclo- and Polytphosphazenel Materials. February 15–16, 1996. at the CNR Research Area in Padova, Italy. 相似文献
118.
Dietary CLA supplementation of pigs confers higher oxidative stability to Ciauscolo and Fabriano salami produced from their meat with no negative impact on the physico‐chemical,microbiological and sensorial characteristics 下载免费PDF全文
119.
Soheila Lashgari Mohammad Karrabi Ismaeil Ghasemi Hamed Azizi Massimo Messori 《Iranian Polymer Journal》2016,25(2):193-202
Poly(l-lactic acid) (PLLA)/graphene nanoplatelets (GnP) nanocomposites were prepared through solvent casting and coagulation methods. The better dispersion of graphene was achieved by ultrasounds and its effect on crystallinity, thermomechanical and electrical properties of PLLA were studied and compared in both methods. Differential scanning calorimetry (DSC) was used to investigate the crystallinity of PLLA and its composites. Field emission gun scanning electron microscope (FEG-SEM) and wide-angle X-ray scattering (WAXS) were employed to characterize the microstructure of PLLA crystallites. Dynamic mechanical thermal analysis (DMTA) was performed to study the thermomechanical properties of the nanocomposites. FEG-SEM images illustrated finer dispersion of GnP in samples obtained by coagulation method with respect to solvent casting method. Graphene imparted higher electrical conductivity to nanocomposites obtained by solvent casting under ultrasound due to better formation of graphene network. DSC thermograms and their resulting data showed positive effects of GnP on crystallization kinetics of PLLA in both methods enhanced by the nucleating effect of graphene particles. Meanwhile, the effect of GnP, as nucleating agent, was more prominent in samples produced by coagulation method without utilization of ultrasounds. WAXS patterns represented the same characteristic peaks of PLLA in nanocomposite specimens suggesting similar crystalline structure of PLLA in presence of graphene, and the intensified peaks of nanocomposites compared to neat PLLA confirmed the DSC results regarding its improved crystallinity. Graphene increased storage modulus in rubbery region and glass transition temperature of nanocomposites in the coagulation method due to restricted mobility of PLLA chains. 相似文献
120.
Dr. Elena Marchesi Dr. Nicola Chinaglia Dr. Massimo L. Capobianco Dr. Paolo Marchetti Tzu-En Huang Hao-Cheng Weng Dr. Jih-Hwa Guh Dr. Lih-Ching Hsu Dr. Daniela Perrone Dr. Maria Luisa Navacchia 《ChemMedChem》2019,14(7):779-787
A series of hybrid compounds based on natural products—bile acids and dihydroartemisinin—were prepared by different synthetic methodologies and investigated for their in vitro biological activity against HL-60 leukemia and HepG2 hepatocellular carcinoma cell lines. Most of these hybrids presented significantly improved antiproliferative activities with respect to dihydroartemisinin and the parent bile acid. The two most potent hybrids of the series exhibited a 10.5- and 15.4-fold increase in cytotoxic activity respect to dihydroartemisinin alone in HL-60 and HepG2 cells, respectively. Strong evidence that an ursodeoxycholic acid hybrid induced apoptosis was obtained by flow cytometric analysis and western blot analysis. 相似文献