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Carlo Bottoni Francesca Marcoccia Chiara Compagnoni Martina Colapietro Alessia Sabatini Giuseppe Celenza Bernardetta Segatore Maria Giovanna Maturo Gianfranco Amicosante Mariagrazia Perilli 《Antimicrobial agents and chemotherapy》2015,59(8):4990-4993
Two new natural CphA metallo-β-lactamases, the CphA4 and CphA5 enzymes, were identified in water samples from municipal sewage in central Italy. Compared to CphA, the CphA4 and CphA5 enzymes showed numerous point mutations. These enzymes have a narrow spectrum of substrates focused on carbapenems only. CphA5 showed kcat values about 40-, 12-, and 97-fold higher than those observed for CphA4 versus imipenem, ertapenem, and biapenem, respectively. 相似文献
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Lugaresi A Di Iorio A Iarlori C Reale M De Luca G Sparvieri E Michetti A Conti P Gambi D Abate G Paganelli R 《Experimental gerontology》2004,39(4):653-657
Cytokines appear to be involved in the pathogenesis of Alzheimer's Disease (AD). Their modulation by treatment has been investigated only in a few studies. The aim of our study was to evaluate the effect of acetylcholinesterase inhibitors (AChEI) on Interleukin-4 (IL-4) production in AD patients. IL-4 levels were measured by ELISA on peripheral blood mononuclear cell cultures in the presence or absence of Concanavalin A or Phytohaemagglutinin. Linear regression analysis shows that patients who have been treated, have higher levels of IL-4 independently from age, gender and comorbidity. The increased production of IL-4 in AChEI treated patients might represent an additional mechanism through which AChEI act on AD progression. 相似文献
45.
Antonella Meloni Daniele De Marchi Vincenzo Positano Maria Giovanna Neri Maurizio Mangione Petra Keilberg Maddalena Lendini Carla Cirotto Alessia Pepe 《Abdominal imaging》2015,40(8):3129-3136
Purpose
We examined different approaches aimed to deal with the signal fluctuation of pancreatic T2* values due to fat infiltration in order to obtain accurate estimates of iron overload.Methods
Pancreatic T2* values were assessed in 20 patients (13 females, 37.24 ± 9.12 years) enrolled in the Myocardial Iron Overload in Thalassemia network without and with the application of fat suppression-FS (T2*-NoFS and T2*-FS). T2* values were assessed in three different ways: (1) from the immediate fit (original T2*); (2) discarding the echoes until the achievement of a good visual concordance between the signal and the model (final_vis T2*); (3) eliminating the echoes until the achievement of a fitting error (known) <5% (final_thres T2*).Results
For the T2*-NoFS sequence the original T2* values were significantly higher than the final_vis T2* values (difference:4.8 ± 6.1 ms; P < 0.0001) and the final_thres T2* values (difference:4.3 ± 6.1 ms; P = 0.006). For the T2*-FS sequence the original T2* values were comparable to final_vis and final_thres T2* values. The original T2*-FS values were significantly different from the original T2*-NoFS values. The final_vis T2*-FS values were comparable to the final_vis T2*-NoFS values and the final_thresh T2*-FS values were comparable to the final_thresh T2*-NoFS values. For both T2*-FS and T2*-NoFS sequences, the final_thres T2* values were not significantly different from the final_vis T2* values and no bias was present.Conclusions
In the clinical practice, an accurate pancreatic iron overload assessment should be done by applying FS and, when needed, by discarding the TEs until the fitting error goes below 5%.46.
Simona Attardo Viveksandeep Thoguluva Chandrasekar Marco Spadaccini Roberta Maselli Harsh K Patel Madhav Desai Antonio Capogreco Matteo Badalamenti Piera Alessia Galtieri Gaia Pellegatta Alessandro Fugazza Silvia Carrara rea Anderloni Pietro Occhipinti Cesare Hassan Prateek Sharma Alessandro Repici 《World journal of gastroenterology : WJG》2020,26(37):5606-5616
Several studies have shown a significant adenoma miss rate up to 35% during screening colonoscopy, especially in patients with diminutive adenomas. The use of artificial intelligence(AI) in colonoscopy has been gaining popularity by helping endoscopists in polyp detection, with the aim to increase their adenoma detection rate(ADR) and polyp detection rate(PDR) in order to reduce the incidence of interval cancers. The efficacy of deep convolutional neural network(DCNN)-based AI system for polyp detection has been trained and tested in ex vivo settings such as colonoscopy still images or videos. Recent trials have evaluated the real-time efficacy of DCNN-based systems showing promising results in term of improved ADR and PDR. In this review we reported data from the preliminary ex vivo experiences and summarized the results of the initial randomized controlled trials. 相似文献
47.
Alessia Rosetti Rosella Ferretti Leo Zanitti Adriano Casulli Claudio Villani Roberto Cirilli 《Journal of Pharmaceutical Analysis》2020,10(6):610-616
A direct enantio-, diastereo-, and chemo-selective high-performance liquid chromatographic method was developed for determining the content, enantiomeric purity, and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run. The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate) under reversed-phase conditions. The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity. The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min, without using buffers or tandem-coupled columns. The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation. 相似文献
48.
Adriano Schimmenti Alessia Passanisi Alessia Maria Gervasi Sergio Manzella Francesca Isabella Famà 《Child psychiatry and human development》2014,45(5):588-595
Studies on the role played by attachment attitudes among late adolescents who show Problematic Internet Use (PIU) are still lacking. Three self-report measures concerning attachment attitudes, childhood experiences of abuse, and Internet addiction were administered to 310 students (49 % males) aged 18–19 attending the last year of high school. Students who screened positive for PIU were more likely to be male and to have suffered childhood experiences of physical and sexual abuse; they also scored higher than the other participants on scales assessing anxious and avoidant attachment attitudes. A logistic regression showed that the classification of participants in the PIU group was predicted by male gender, having suffered from physical and sexual abuse in childhood, and preoccupation with relationships. Keeping constant the effects of gender and childhood experiences of abuse in the equation model, increasing values of preoccupation with relationships were reflected by an exponential growth in the probability curve for PIU classification. Findings of the study support the hypothesis that insecure attachment attitudes (particularly the preoccupation with relationships) are involved in the development of PIU among late adolescents. 相似文献
49.
A Capotondo R Milazzo LS Politi A Quattrini A Palini T Plati S Merella A Nonis C di Serio E Montini L Naldini A Biffi 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(37):15018-15023
The recent hypothesis that postnatal microglia are maintained independently of circulating monocytes by local precursors that colonize the brain before birth has relevant implications for the treatment of various neurological diseases, including lysosomal storage disorders (LSDs), for which hematopoietic cell transplantation (HCT) is applied to repopulate the recipient myeloid compartment, including microglia, with cells expressing the defective functional hydrolase. By studying wild-type and LSD mice at diverse time-points after HCT, we showed the occurrence of a short-term wave of brain infiltration by a fraction of the transplanted hematopoietic progenitors, independently from the administration of a preparatory regimen and from the presence of a disease state in the brain. However, only the use of a conditioning regimen capable of ablating functionally defined brain-resident myeloid precursors allowed turnover of microglia with the donor, mediated by local proliferation of early immigrants rather than entrance of mature cells from the circulation. 相似文献
50.