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排序方式: 共有1014条查询结果,搜索用时 171 毫秒
1.
Francesca Pecori‐Giraldi Giuseppina Manzoni Jorgo Michailidis Massimo Scacchi Marco Stramba‐Badiale Francesco Cavagnini 《Obesity (Silver Spring, Md.)》2011,19(10):2015-2018
Obese subjects show several electrocardiographic alterations, including prolonged QT interval, a marker for fatal cardiac arrhythmias. Prolonged QT interval has recently been linked to low testosterone levels, a frequent occurrence in male obese patients but no study has yet assessed whether hypoandrogenism contributes to QT interval prolongation in this population. Aim of this study was to evaluate whether prolonged QT interval is linked to hypogonadism in male obese subjects. QT interval corrected for heart rate (QTc) was measured from standard electrocardiogram recordings in 136 obese men (BMI 30 >kg/m2, range 30.1–75.4 kg/m2). Obese men were classified as eugonadal or hypogonadal according to serum total testosterone levels (i.e., greater or less than 9.9 nmol/l). Our study showed that QTc measurements corrected by either Bazett (419 ± 3.2 vs. 408 ± 3.4 ms, P < 0.05), Fridericia (406.3 ± 3.39 vs. 396.4 ± 3.03 ms, P < 0.05) or Hodges (407.0 ± 3.12 vs. 397.3 ± 2.84 ms, P < 0.05) were longer in hypogonadal compared with eugonadal obese men; further, prolonged QTc interval (i.e., >440 ms) was more frequent among hypogonadal compared with eugonadal obese men (23% vs. 10%, P < 0.05). The degree of weight excess, diabetes, sleep apnoea and potassium levels were not associated with prolonged QTc. In conclusion, obese hypogonadal men show a greater prevalence of prolonged QT interval compared with their eugonadal counterparts. It appears therefore that low levels of testosterone in obese men may contribute to the arrhythmogenic profile of these patients, a heretofore unknown link which warrants further clinical attention. 相似文献
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Cure of Helicobacter pylori in Children 总被引:1,自引:0,他引:1
Giuseppina Oderda 《Helicobacter》1997,2(S1):73-76
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Simona Maria Monti Giuseppina De Simone Nina A. Dathan Martha Ludwig Daniela Vullo Andrea Scozzafava Clemente Capasso Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2013,23(6):1626-1630
Several β-carbonic anhydrases (CAs, EC 4.2.1.1) are present in all land plants examined thus far. Here we report the first detailed biochemical characterization of one such isoform, FbiCA 1, from the C4 plant Flaveria bidentis, which was cloned, purified and characterized as recombinant protein. FbiCA 1 has an interesting CO2 hydrase catalytic activity (kcat of 1.2 × 105 and kcat/Km of 7.5 × 106 M?1 × s?1) and was moderately inhibited by most simple/complex inorganic anions. Potent FbiCA 1 inhibitors were also detected, such as trithiocarbonate, diethyldithiocarbamate, sulfamide, sulfamic acid, phenylboronic acid and phenylarsonic acid (KIs in the range of 4–60 μM). Such inhibitors may be used as tools to better understand the role of various β-CA isoforms in photosynthesis. 相似文献
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Letizia Antonilli Anna Rita Togna Giovanna Sabatini Alessandro Venditti Laura Guarcini Giuseppina I. Togna Rosario Nicoletti Filomena Sanasi Armandodoriano Bianco Paolo Nencini 《Bioorganic & medicinal chemistry》2013,21(24):7955-7963
We have previously found that phenanthrenic opioids, including codeine, modulate morphine glucuronidation in the rat. Here codeine and five of its derivatives were compared in their effects on the synthesis of morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) from morphine by rat liver microsomal preparations, and by primary cultures of rat hepatocytes previously incubated for 72 h with either codeine or its derivatives. Acetylcodeine and pivaloylcodeine shared the capability of the parent compound of inhibiting the synthesis of M3G by liver microsomes through a noncompetitive mechanism of action. Their IC50 were 3.25, 2.27, and 4.32 μM, respectively. Dihydrocodeine, acetyldihydrocodeine, and lauroylcodeine were ineffective. In all the experimental circumstances M6G was undetectable in the incubation medium. In primary hepatocyte cultures codeine only inhibited M3G formation, but with a lower efficacy than that observed with microsomes (IC50 20.91 vs 4.32 μM). Preliminary results show that at micromolar concentrations codeine derivatives exhibit a low rate of affinity for μ opiate receptors. In conclusion, acetyl and pivaloyl derivatives of codeine noncompetitively inhibit liver glucuronidation of morphine interacting with microsomes. This study further strengths the notion that phenanthrenic opioids can modulate morphine glucuronidation independently from their effects on μ opiate receptors. 相似文献
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Giuseppina Brasile Laura Mauri Sandro Sonnino Federica Compostella Fiamma Ronchetti 《Amino acids》2013,44(2):435-441
An efficient method for the synthesis of long-chain α,ω-diamino acids, starting from natural α-amino acids, has been developed. The long-chain skeleton has been generated through condensation between a protected aldehyde, derived from l-aspartic acid, and an ylide obtained from an ω-hydroxy-alkyl phosphonium salt. After conversion of the ω-hydroxy group into an amine, catalytic hydrogenation produced the N,N′-protected α,ω-diamino acid. The present route to α,ω-diamino acids allows the modulation of the chain length depending on the length of the ylide used for the Wittig olefination reaction. 相似文献
8.
Maria Teresa Montagna Caterina Coretti Antonella Rella Giovanna Barbuti Fabio Manca Osvaldo Montagna Nicola Laforgia Giuseppina Caggiano 《Folia microbiologica》2013,58(1):27-31
Candidemia is a major infectious complication in neonatal patients. The isolation of yeasts from blood is still the ??gold standard?? for its diagnosis, but other laboratory markers (i.e., circulating antigens) have been studied with varying specificities and sensitivities. The aim of this study was to evaluate the role of procalcitonin for the diagnosis of candidemia in neonatal patients at high risk. To verify if the use of different commercial methods can highlight dissimilar results of sensitivity and/or specificity, the determination of procalcitonin serum levels was estimated by two systems. Overall, 90 patients from a Neonatal Intensive Care Units were enrolled, of whom six developed Candida bloodstream infection. Four of six infants with candidemia had slight increase of procalcitonin values (0.5?C1?ng/mL). Only one baby showed very high levels but he had fungal and bacterial sepsis at the same time, while no elevation was observed in the sixth patient. No statistically significant difference was observed between two different methods at the time of monitoring (p?>?0.643). Both methods showed a sensitivity of 83.3?% at diagnosis, while the specificity was 73.8 and 63.1?% by methods A and B, respectively. In the light of the low sensibility and specificity of this assay, we can assume that the determination of procalcitonin would not seem to play a significant role in the diagnosis of fungal infection in neonatal patients. 相似文献
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Maya D. Lambreva Maria Teresa Giardi Irene Rambaldi Amina Antonacci Sandro Pastorelli Ivo Bertalan Ivan Husu Udo Johanningmeier Giuseppina Rea 《PloS one》2013,8(4)
This study was prompted by increasing concerns about ecological damage and human health threats derived by persistent contamination of water and soil with herbicides, and emerging of bio-sensing technology as powerful, fast and efficient tool for the identification of such hazards. This work is aimed at overcoming principal limitations negatively affecting the whole-cell-based biosensors performance due to inadequate stability and sensitivity of the bio-recognition element. The novel bio-sensing elements for the detection of herbicides were generated exploiting the power of molecular engineering in order to improve the performance of photosynthetic complexes. The new phenotypes were produced by an in vitro directed evolution strategy targeted at the photosystem II (PSII) D1 protein of Chlamydomonas reinhardtii, using exposures to radical-generating ionizing radiation as selection pressure. These tools proved successful to identify D1 mutations conferring enhanced stability, tolerance to free-radical-associated stress and competence for herbicide perception. Long-term stability tests of PSII performance revealed the mutants capability to deal with oxidative stress-related conditions. Furthermore, dose-response experiments indicated the strains having increased sensitivity or resistance to triazine and urea type herbicides with I50 values ranging from 6×10−8 M to 2×10−6 M. Besides stressing the relevance of several amino acids for PSII photochemistry and herbicide sensing, the possibility to improve the specificity of whole-cell-based biosensors, via coupling herbicide-sensitive with herbicide-resistant strains, was verified. 相似文献