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31.
Silvio Borrelli Ida Matarazzo Eugenio Lembo Laura Peccarino Claudia Annoiato Maria Rosaria Scognamiglio Andrea Foderini Chiara Ruotolo Aldo Franculli Federica Capozzi Pavlo Yavorskiy Fatme Merheb Michele Provenzano Gaetano La Manna Luca De Nicola Roberto Minutolo Carlo Garofalo 《International journal of molecular sciences》2022,23(12)
Increasing potassium intake ameliorates blood pressure (BP) and cardiovascular (CV) prognoses in the general population; therefore the World Health Organization recommends a high-potassium diet (90–120 mEq/day). Hyperkalaemia is a rare condition in healthy individuals due to the ability of the kidneys to effectively excrete dietary potassium load in urine, while an increase in serum K+ is prevalent in patients with chronic kidney disease (CKD). Hyperkalaemia prevalence increases in more advanced CKD stages, and is associated with a poor prognosis. This scenario generates controversy on the correct nutritional approach to hyperkalaemia in CKD patients, considering the unproven link between potassium intake and serum K+ levels. Another concern is that drug-induced hyperkalaemia leads to the down-titration or withdrawal of renin-angiotensin system inhibitors (RASI) and mineralocorticoids receptors antagonists (MRA) in patients with CKD, depriving these patients of central therapeutic interventions aimed at delaying CKD progression and decreasing CV mortality. The new K+-binder drugs (Patiromer and Sodium-Zirconium Cyclosilicate) have proven to be adequate and safe therapeutic options to control serum K+ in CKD patients, enabling RASI and MRA therapy, and possibly, a more liberal intake of fruit and vegetables. 相似文献
32.
This study describes a hierarchical ranking model to help the selection of CRM (customer relationship management) packages based on their functional and technical quality. The model is tested empirically by applying the hierarchical analytical process (AHP) to a sample of 42 CRM packages. Results indicate how functionally similar packages can differ substantially in their technical quality and, thus, in their ability to be integrated within a companys information system. The hierarchical model is verified to be dependable, since the quality-based ranking of packages is found to have a low rank-reversal probability as a consequence of managers uncertainty in weighing the relevance of different quality variables. From a practical standpoint, these results confirm that CRM packages differentiate in measurable quality variables, which can be used by practitioners as a framework to gather and evaluate software-selection information during feasibility analyses. 相似文献
33.
Verocytotoxin-producing Escherichia coli (VTEC) has emerged as a foodborne pathogen that can cause severe and potentially fatal illnesses, such as hemorrhagic colitis or the hemolytic uremic syndrome. In this study, 182 cattle at slaughter (119 dairy cows and 63 feedlot cattle) were randomly selected and tested for the presence of VTEC serogroups O26, O103, O111, O145, and O157 in their cecal content and lymphatic tissue (tonsils or mesenteric lymph nodes). A total of 364 samples were evaluated with an immunomagnetic separation technique followed by slide agglutination. Presumptive VTEC 026, O103, O111, O145, and O157 isolates were tested by Vero cell assay for verocytotoxin production and by multiplex PCR assay for the detection of vtxl, vtx2, eae, and E-hlyA genes. VTEC O157 was detected in 6 (3.3%) of 182 animals, and VTEC 026 was detected in 1 (0.5%) of 182 animals. No VTEC O103, VTEC O111, or VTEC O145 isolates were found in cattle feces, but one VTEC O91:H- vtx2+, eae-, E-hlyA+ strain nonspecifically cross-reacted with the VTEC O103 type. The prevalence of VTEC O157 in the lymphatic tissue of cattle was 1.1% in both tonsils (1 of 93 samples) and mesenteric lymph nodes (1 of 89 samples). Lymphatic tissue contamination was observed only in VTEC O157 intestinal carriers; two (33.3%) of six fecal carriers were simultaneously VTEC O157 lymphatic carriers. This finding suggests that VTEC O157 contamination of meat does not necessarily come from feces or the environment. No other VTEC serogroups were detected in the lymphatic tissue of slaughtered cattle. 相似文献
34.
Fabio Pianesi Massimo Zancanaro Elena Not Chiara Leonardi Vera Falcon Bruno Lepri 《Personal and Ubiquitous Computing》2008,12(3):181-195
The complexity of group dynamics occurring in small group interactions often hinders the performance of teams. The availability
of rich multimodal information about what is going on during the meeting makes it possible to explore the possibility of providing
support to dysfunctional teams from facilitation to training sessions addressing both the individuals and the group as a whole.
A necessary step in this direction is that of capturing and understanding group dynamics. In this paper, we discuss a particular
scenario, in which meeting participants receive multimedia feedback on their relational behaviour, as a first step towards
increasing self-awareness. We describe the background and the motivation for a coding scheme for annotating meeting recordings
partially inspired by the Bales’ Interaction Process Analysis. This coding scheme was aimed at identifying suitable observable
behavioural sequences. The study is complemented with an experimental investigation on the acceptability of such a service.
相似文献
Fabio Pianesi (Corresponding author)Email: |
Massimo ZancanaroEmail: |
Elena NotEmail: |
Chiara LeonardiEmail: |
Vera FalconEmail: |
Bruno LepriEmail: |
35.
Dr. Laura Braconi Prof. Elisabetta Teodori Dr. Marialessandra Contino Prof. Chiara Riganti Prof. Gianluca Bartolucci Dr. Dina Manetti Prof. Maria Novella Romanelli Dr. Maria Grazia Perrone Prof. Nicola Antonio Colabufo Prof. Stefano Guglielmo Prof. Silvia Dei 《ChemMedChem》2022,17(12):e202200027
Some 2,4-disubstituted quinazolines were synthesized and studied as multidrug resistance (MDR) reversers. The new derivatives carried the quinazoline-4-amine scaffold found in modulators of the ABC transporters involved in MDR, as the TKIs gefitinib and erlotinib. Their behaviour on the three ABC transporters, P-gp, MRP1 and BCRP, was investigated. Almost all compounds inhibited the P-gp activity in MDCK-MDR1 cells overexpressing P-gp, showing EC50 values in the nanomolar range ( 1 d , 1 e , 2 a , 2 c , 2 e ). Some compounds were active also towards MRP1 and/or BCRP. Docking results obtained by in silico studies on the P-gp crystal structure highlighted common features for the most potent compounds. The P-gp selective compound 1 e was able to increase the doxorubicin uptake in HT29/DX cells and to restore its antineoplastic activity in resistant cancer cells in the same extent of sensitive cells. Compound 2 a displayed a dual inhibitory effect showing good activities towards both P-gp and BCRP. 相似文献
36.
Lara Alessandrini Leonardo Franz Marta Sbaraglia Tommaso Saccardo Filippo Cappello Alessandro Drigo Anna Chiara Frigo Gino Marioni 《International journal of molecular sciences》2022,23(14)
Programmed cell death ligand 1 (PD-L1) seems to rely on close relations between neoplastic and immune cells in the tumor microenvironment. Tumor to stroma ratio (TSR) has been associated with prognosis in different malignancies. The aims of this exploratory investigation were to analyze for the first time the: (i) association between TSR, PD-L1 expression and other clinical–pathological features in laryngeal squamous cell carcinoma (LSCC) biopsies and paired surgical specimens; (ii) prognostic and predictive role of TSR and PD-L1. TSR, PD-L1 expression (in terms of combined positive score [CPS]), and other clinical–pathological features were analyzed in biopsies and surgical specimens of 43 consecutive LSCC cases. A CPS < 1 evaluated on surgical specimens was associated with a low TSR (stroma rich) on both biopsies and surgical specimens (p = 0.0143 and p = 0.0063). Low TSR showed a significant negative prognostic value when evaluated on both biopsies and surgical specimens (HR = 8.808, p = 0.0003 and HR = 11.207, p = 0.0002). CPS ≥ 1 appeared to be a favorable prognostic factor (HR = 0.100, p = 0.0265). The association between bioptic and surgical specimen TSR and PD-L1 expression should be further investigated for a potential impact on targeted treatments, also with regard to immunotherapeutic protocols. 相似文献
37.
Claudia Giuseppina Fresta Giuseppe Caruso Annamaria Fidilio Chiara Bianca Maria Platania Nicol Musso Filippo Caraci Filippo Drago Claudio Bucolo 《International journal of molecular sciences》2020,21(23)
Activation of P2X7 signaling, due to high glucose levels, leads to blood retinal barrier (BRB) breakdown, which is a hallmark of diabetic retinopathy (DR). Furthermore, several studies report that high glucose (HG) conditions and the related activation of the P2X7 receptor (P2X7R) lead to the over-expression of pro-inflammatory markers. In order to identify novel P2X7R antagonists, we carried out virtual screening on a focused compound dataset, including indole derivatives and natural compounds such as caffeic acid phenethyl ester derivatives, flavonoids, and diterpenoids. Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) rescoring and structural fingerprint clustering of docking poses from virtual screening highlighted that the diterpenoid dihydrotanshinone (DHTS) clustered with the well-known P2X7R antagonist JNJ47965567. A human-based in vitro BRB model made of retinal pericytes, astrocytes, and endothelial cells was used to assess the potential protective effect of DHTS against HG and 2′(3′)-O-(4-Benzoylbenzoyl)adenosine-5′-triphosphate (BzATP), a P2X7R agonist, insult. We found that HG/BzATP exposure generated BRB breakdown by enhancing barrier permeability (trans-endothelial electrical resistance (TEER)) and reducing the levels of ZO-1 and VE-cadherin junction proteins as well as of the Cx-43 mRNA expression levels. Furthermore, HG levels and P2X7R agonist treatment led to increased expression of pro-inflammatory mediators (TLR-4, IL-1β, IL-6, TNF-α, and IL-8) and other molecular markers (P2X7R, VEGF-A, and ICAM-1), along with enhanced production of reactive oxygen species. Treatment with DHTS preserved the BRB integrity from HG/BzATP damage. The protective effects of DHTS were also compared to the validated P2X7R antagonist, JNJ47965567. In conclusion, we provided new findings pointing out the therapeutic potential of DHTS, which is an inhibitor of P2X7R, in terms of preventing and/or counteracting the BRB dysfunctions elicited by HG conditions. 相似文献
38.
Vincenzo Calemma Chiara Gambaro Wallace O. Parker Rosa Carbone Roberto Giardino Pietro Scorletti 《Catalysis Today》2010,149(1-2):40-46
A light cobalt catalyzed Fischer–Tropsch (FT) wax was subjected to hydrocracking in the range of temperature 319–351 °C and hydrogen pressure between 3.5 and 6.0 MPa. The catalyst used was platinum on amorphous silica–alumina. Hydrocracking reaction led to an increase of middle distillate yield up to 85% with a contemporary increase of iso-paraffins concentration which resulted in a remarkable improvement of cold flow properties of the products. The freezing point of C10–C14 fraction passed from ?23 to ?45 °C while the pour point of C15–C22 fraction decreased from 13 to ?23 °C. The latter fraction displayed high cetane numbers ranging between 75 and 80. Changes in carbon distribution and molecular structure of products during hydrocracking have been rationalized in the light of the accepted hydrocracking mechanism where n-paraffins undergo to consecutive isomerization reactions leading to isomers with progressively higher branching degree and concomitant cracking reaction. Experimental evidences support the view that apparent reactivity of n-paraffins is chain length dependent, increasing with the molecular weight. Detailed characterization by NMR and GC showed that branching groups abundance in the middle distillate products was the following: methyl ? ethyl > propyl.Emission tests carried out with FT diesel and commercial ultra low sulfur diesel showed that FT diesel has excellent combustion properties and leads to a reduction of emissions. 相似文献
39.
The evolution of viscoelasticity within a solution of guar gum (GG) in the presence of an excess of cross-linker (glutaraldehyde, Ga) has been monitored, at different temperatures (7, 15, 25 and 37 °C), evaluating the sol–gel transition by means of dynamic mechanical experiments. Furthermore, at 25 °C, the samples were characterized as a function of the different amounts of cross-linker. The gelation time of the systems, evaluated with the loss tangent, decreased with increasing temperature and, at a fixed temperature (25 °C), decreased with increasing cross-linker concentration. At the gel point a power-law frequency dependence of the dynamic storage modulus (G′≈ωn) and loss modulus (G″≈ωn) was observed. The value of n, evaluated according to three different methods (nslope, considering the parallelism of the two moduli, ntan, from the frequency-independence of tan δ, and from the crossing point between the apparent exponents of G′ and G″, napp), decreases with increasing cross-linking densities and with increasing temperature. The fractal dimension (df) was determined for the incipient GG/Ga hydrogels. The value of df increases with increasing cross-linker concentration and decreases with increasing temperature. This trend of df suggests a more “tight” structure of the network at higher cross-linking densities and at lower temperatures. The activation energy (Ea) of the chemical reaction between GG and Ga was estimated: the experimental value was close to those obtained in the case of similar chemical reactions among polymers and different kinds of cross-linkers. 相似文献
40.
Elisa Mascolo Francesco Liguori Lorenzo Stufera Mecarelli Noemi Amoroso Chiara Merigliano Susanna Amadio Cinzia Volont Roberto Contestabile Angela Tramonti Fiammetta Vernì 《International journal of molecular sciences》2021,22(2)
Maturity-onset diabetes of the young (MODY) type 2 is caused by heterozygous inactivating mutations in the gene encoding glucokinase (GCK), a pivotal enzyme for glucose homeostasis. In the pancreas GCK regulates insulin secretion, while in the liver it promotes glucose utilization and storage. We showed that silencing the Drosophila GCK orthologs Hex-A and Hex-C results in a MODY-2-like hyperglycemia. Targeted knock-down revealed that Hex-A is expressed in insulin producing cells (IPCs) whereas Hex-C is specifically expressed in the fat body. We showed that Hex-A is essential for insulin secretion and it is required for Hex-C expression. Reduced levels of either Hex-A or Hex-C resulted in chromosome aberrations (CABs), together with an increased production of advanced glycation end-products (AGEs) and reactive oxygen species (ROS). This result suggests that CABs, in GCK depleted cells, are likely due to hyperglycemia, which produces oxidative stress through AGE metabolism. In agreement with this hypothesis, treating GCK-depleted larvae with the antioxidant vitamin B6 rescued CABs, whereas the treatment with a B6 inhibitor enhanced genomic instability. Although MODY-2 rarely produces complications, our data revealed the possibility that MODY-2 impacts genome integrity. 相似文献