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41.
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection.  相似文献   
42.
BackgroundH. pylori infection induce atrophic gastritis (AG) and intestinal metaplasia (IM) that can lead to gastric cancer (GC). The severity of gastric lesions is related to H. pylori genetic diversity. The oncogenic potential of H. pylori cagA virulence factor is linked to its high polymorphic EPIYA motifs.ObjectivesOur aim was to evaluate the association of EPIYA motifs with the risk of AG and IM in Casablanca population.MethodsA total of 210 patients suffering from gastric lesions (chronic gastritis, AG, and IM) was enrolled. H. pylori infection and the type of lesions were diagnosed by ureC PCR and histological examination, respectively. Detection of the cagA gene, and the type of EPIYA motifs, were carried out by PCRResultsThe prevalence of H. pylori and cagA gene was 95% and 37%, respectively. CagA-positive strains were associated with the risk of IM. The EPIYA motifs detected were: EPIYA-ABC (58%), EPIYA-ABCC (22%), and EPIYA-AB (20%). The EPIYA-ABCC motif was associated with the risk of IM (p-value = 0.007), compared to AG (p-value = 0.28).ConclusionThe EPIYA-ABCC motif might be a useful marker for the identification of patients at high risk of developing IM that can lead to GC.  相似文献   
43.
BackgroundPenicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study.MethodsThe metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis.ResultsGC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml−1. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model.ConclusionMetabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics.

Key messages

  • The first time explored complete metabolome through GC-MS and LC-MS-QTOF.
  • Both in vivo & in vitro pharmacological investigation of P. claviforme.
  • In silico molecular docking of LC-MS-QTOF metabolites.
  相似文献   
44.
IntroductionThere is a scarcity of data on the impact of behavioral habits, such as exercise, on physical health in patients with bladder cancer. We investigated the association of exercise on self-reported physical health status and examined the prevalence of bladder cancer patients with sedentary lifestyle.MethodsWe examined cross-sectional data of participants diagnosed with bladder cancer within the Behavioral Risk Factor Surveillance System (BRFSS) from 2016–2020. Patient health status was surveyed using self-reported measures, such as the total days per month when their “physical health is not good.” The primary outcome was patient-reported poor physical health for more than 14 days within a one-month period.ResultsOut of 2 193 981 survey participants, we identified 936 with a history of bladder cancer. Nearly one in three bladder cancer patients reported being sedentary within the last month, as a total of 307 (32.8%) patients reported no exercise within the last 30 days. The remaining 628 (67.2%) reported exercising for at least one day within the last month. In multivariable logistic regression model analysis, we found that exercise is protective for self-reported poor physical health status (odds ratio 0.37, 95% confidence interval 0.25–0.56, p<0.001). Patients that exercised were less likely to report bad physical health.ConclusionsApproximately one in three bladder cancer patients report no exercise within 30 days, suggesting a sedentary lifestyle. Patients that are active are less likely to self-report poor physical health status. Implementation of exercise programs for bladder cancer patients could be promising in improving health status.

KEY MESSAGES
  • Approximately 1 in 3 bladder cancer patients report a sedentary lifestyle.
  • Patients that are active are less likely to self-report poor physical health status.
  • Implementation of exercise programs might improve health status.
  • Clinicians of bladder cancer patients should engage in increasing activity levels.
  相似文献   
45.
46.
This paper discusses the features of ω-phase formation and its thermal stability depending on the phase composition, alloying element and the grain size of the initial microstructure of Ti–Nb and Ti–Mo alloys subjected to high-pressure torsion (HPT) deformation. In the case of two-phase Ti–3wt.% Nb and Ti–20wt.% Nb alloys with different volume fractions of α- and β-phases, a complete β→ω phase transformation and partial α→ω transformation were found. The dependence of the α→ω transformation on the concentration of the alloying element was determined: the greater content of Nb in the α-phase, the lower the amount of ω-phase that was formed from it. In the case of single-phase Ti–Mo alloys, it was found that the amount of ω-phase formed from the coarse-grained β-phase of the Ti–18wt.% Mo alloy was less than the amount of the ω-phase formed from the fine α′-martensite of the Ti–2wt.% Mo alloy. This was despite the fact that the ω-phase is easier to form from the β-phase than from the α- or α′-phase. It is possible that the grain size of the microstructure also affected the phase transformation, namely, the fine martensitic plates more easily gain deformation and overcome the critical shear stresses necessary for the phase transformation. It was also found that the thermal stability of the ω-phase in the Ti–Nb and Ti–Mo alloys increased with the increasing concentration of Nb or Mo.  相似文献   
47.
The aim of the present study was to evaluate the effect of brushing with two whitening dentifrices (Colgate Optic White (COW) and Colgate Optic White Charcoal (COC)) on surface gloss, micro-roughness, and micro-hardness of nanostructured hybrid conventional (Z350) and bulk-fill (Tetric N Ceram bulk-fill) polymer composite. In total, 96 disk samples using two nano-hybrid composite polymers (Z350 and Tetric N Ceram Bulk-fill) were prepared. All specimens were exposed to two different dentifrices (COW and COC), resulting in four main subgroups in the study. Specimens were assessed for surface gloss, micro-roughness (Ra), and micro-hardness using standardized methodology. Means and standard deviations of properties compared using paired t-test, one-way and two-way ANOVA, and post hoc test. The presence of dentifrices did not show any significant difference in micro-hardness values of Z350 (p > 0.05), whereas micro-hardness of bulk-fill composite significantly reduced on dentifrices exposure (p ≤ 0.05). Bulk-fill polymer composite showed significant reduction in gloss after dentifrice exposure (p < 0.05), however, Z350 showed no significant loss of gloss due to dentifrices (p > 0.05). A significant increase in Ra was observed for both resin materials after exposure to dentifrices (COC and COW). Conventional resin composite (Z350) showed comparable surface hardness and gloss before and after dentifrice exposure, however, micro-roughness increased significantly due to dentifrice exposure. Bulk-fill resin (Tetric N Ceram) showed significant loss of micro-hardness and gloss and increase in micro-roughness on dentifrice exposure. Conventional nano-hybrid composite polymer showed better durability in resisting loss of surface properties compared to bulk-fill resin polymer in the present experiment.  相似文献   
48.
A novel series of 1,3,5-triazine analogs was successfully synthesized through conjugation with benzimidazole or 1,2,4-triazole derivatives via a methylenethio linker. The new analogs were in vitro evaluated against HSV-1 in Vero cells; among these analogs, two compounds exhibited good effect in inhibiting HSV-1 replication (for compound 5p: EC50 = 3.5 μg/ml, SI = 358; for compound 5r: EC50 = 5.0 μg/ml, SI = 300) in comparison to acyclovir.  相似文献   
49.
50.
Hematological malignancies express high levels of CD47 as a mechanism of immune evasion. CD47-SIRPα triggers a cascade of events that inhibit phagocytosis. Preclinical research supports several models of antibody-mediated blockade of CD47-SIRPα resulting in cell death signaling, phagocytosis of cells bearing stress signals, and priming of tumor-specific T cell responses. Four different antibody molecules designed to target the CD47-SIRPα interaction in malignancy are currently being studied in clinical trials: Hu5F9-G4, CC-90002, TTI-621, and ALX-148. Hu5F9-G4, a humanized anti-CD47 blocking antibody is currently being studied in four different Phase I trials. These studies may lay the groundwork for therapeutic bispecific antibodies. Bispecific antibody (CD20-CD47SL) fusion of anti-CD20 (Rituximab) and anti-CD47 also demonstrated a synergistic effect against lymphoma in preclinical models. This review summarizes the large body of preclinical evidence and emerging clinical data supporting the use of antibodies designed to target the CD47-SIRPα interaction in leukemia, lymphoma and multiple myeloma.  相似文献   
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