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91.
BACKGROUND: First-line chemotherapy regimens suitable for elderly advanced breast cancer patients are still not defined. PATIENTS AND METHODS: Women with stage III or IV breast cancer aged > or =70 years were enrolled in a phase II study aimed to evaluate both activity and toxicity of weekly paclitaxel. Among 46 planned patients, at least 18 responses and not more than seven unacceptable toxic events are required for a favourable conclusion. Paclitaxel 80 mg/m(2) was administered weekly for 3 weeks every 28 days. RESULTS: Unacceptable toxicity occurred in seven out of 46 patients evaluated for toxicity [15.2%; exact 95% confidence interval (CI) 7.6% to 28.2%] and was represented by one case of febrile neutropenia, one case of severe allergic reaction and five cases of cardiac toxicity. Among 41 patients evaluated for response, a complete response occurred in two (4.9%) patients and a partial response in 20 (48.8%), with an overall response rate of 53.7% (exact 95% CI 38.7% to 67.9%). The median progression-free survival was 9.7 months (95% CI 8.5-18.7) and median survival was 35.8 months (95% CI 19-not defined). CONCLUSIONS: Weekly paclitaxel is highly active in elderly advanced breast cancer patients. Data on cardiovascular complications, however, indicate the need for a careful monitoring of cardiac function before and during chemotherapy.  相似文献   
92.
Nanoporous Au has been subjected to serial block face-scanning electron microscopy (SBF-SEM) 3D-characterisation. Corresponding sections have been digitalized and used to evaluate the associated mechanical properties. Our investigation demonstrates that the sample is homogeneous and isotropic. The effective Young’s modulus estimated by an analytical multiscale approach agrees remarkably well with the values stated in the literature.  相似文献   
93.
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.  相似文献   
94.
The aim of this study was to evaluate whether a correlation existed between saccadic eye movements and visual pathways function in diabetic patients. Saccadic or fast Eye Movement System (EMS) and Visual Evoked Potentials (VEPs) were assessed in 20 insulin-dependent diabetic mellitus (IDDM) patients without long-term complications and in stable metabolic control and in 21 age-matched control subjects. In IDDM patients we observed significantly (p<0.01) longer EMS latency, while EMS velocity and accuracy were similar to those of controls; VEPs showed a significant delay in N75, P100, N145 latencies and significant reduction of N75-P100 and P100-N145 amplitudes. In IDDM patients no relationships between EMS and VEP parameters were found. In conclusion, EMS latency delay suggests an impairment of the saccadic eye movement system, while impaired VEPs may be ascribed to a dysfunction of the visual pathways. The lack of correlation between VEPs impairment and EMS latency delay suggests that in our IDDM patients the delay of saccadic latency cannot be exclusively related to a visual pathways dysfuction and could be ascribed to a diffuse neuronal involvement. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
95.
Recently, the scientific community experienced two revolutionary events. The first was the synthesis of single-layer graphene, which boosted research in many different areas. The second was the advent of quantum technologies with the promise to become pervasive in several aspects of everyday life. In this respect, diamonds and nanodiamonds are among the most promising materials to develop quantum devices. Graphene and nanodiamonds can be coupled with other carbon nanostructures to enhance specific properties or be properly functionalized to tune their quantum response. This contribution briefly explores photoelectron spectroscopies and, in particular, X-ray photoelectron spectroscopy (XPS) and then turns to the present applications of this technique for characterizing carbon nanomaterials. XPS is a qualitative and quantitative chemical analysis technique. It is surface-sensitive due to its limited sampling depth, which confines the analysis only to the outer few top-layers of the material surface. This enables researchers to understand the surface composition of the sample and how the chemistry influences its interaction with the environment. Although the chemical analysis remains the main information provided by XPS, modern instruments couple this information with spatial resolution and mapping or with the possibility to analyze the material in operando conditions at nearly atmospheric pressures. Examples of the application of photoelectron spectroscopies to the characterization of carbon nanostructures will be reviewed to present the potentialities of these techniques.  相似文献   
96.
IntroductionSeveral functional neuroimaging studies on healthy controls and patients with migraine with aura have shown that the activation of functional networks during visual stimulation is not restricted to the striate system, but also includes several extrastriate networks.MethodsBefore and after 4 min of visual stimulation with a checkerboard pattern, we collected functional MRI in 21 migraine with aura (MwA) patients and 18 healthy subjects (HS). For each recording session, we identified independent resting-state networks in each group and correlated network connection strength changes with clinical disease features.ResultsBefore visual stimulation, we found reduced connectivity between the default mode network and the left dorsal attention system (DAS) in MwA patients compared to HS. In HS, visual stimulation increases functional connectivity between the independent components of the bilateral DAS and the executive control network (ECN). In MwA, visual stimulation significantly improved functional connectivity between the independent component pairs salience network and DAS, and between DAS and ECN. The ECN Z-scores after visual stimulation were negatively related to the monthly frequency of aura.ConclusionsIn individuals with MwA, 4 min of visual stimulation had stronger cognitive impact than in healthy people. A higher frequency of aura may lead to a diminished ability to obtain cognitive resources to cope with transitory but important events like aura-related focal neurological symptoms.  相似文献   
97.
While PI3K/AKT/mTOR pathway is altered in a variety of cancers including non small cell lung cancer, abnormalities in this pathway are more common in squamous cell lung carcinoma than in adenocarcinoma of the lung. Moreover, aberrant activation of PI3K/AKT/mTOR pathway is one of the mechanisms of acquired resistance to EGFR-TK inhibitors in patients with adenocarcinoma carrying EGFR activating mutations.  相似文献   
98.
99.
Trazodone is approved for the treatment of major depressive disorders, marketed as immediate release (IR), prolonged release, and once a day (OAD) formulation. The different formulations allow different administration schedules and may be useful to facilitate patients’ compliance to the antidepressant treatment. A previously verified physiologically‐based pharmacokinetic model based on in vitro and in vivo information on trazodone pharmacokinetics was applied, aiming at predicting brain receptor occupancy (RO) after single and repeated dosing of the IR formulation and repeated dosing of the OAD formulation in healthy subjects. Receptors included in the simulations were selected using static calculations of RO based on the maximum unbound brain concentration (Cmax,brain,u) of trazodone for each formulation and dosing scheme, resulting in 16 receptors being simulated. Seven receptors were simulated for the IR low dose formulation (30 mg), with similar t onset and duration of coverage (range: 0.09–0.25 h and 2.1–>24 h, respectively) as well as RO (range: 0.64–0.92) predicted between day 1 and day 7 of dosing. The 16 receptors evaluated for the OAD formulation (300 mg) showed high RO (range: 0.97–0.84 for the receptors also covered by the IR formulation and 0.73–0.48 for the remaining) correlating with affinity and similar duration of time above the target threshold to the IR formulation (range: 2–>24 h). The dose‐dependent receptor coverage supports the multimodal activity of trazodone, which may further contribute to its fast antidepressant action and effectiveness in controlling different symptoms in depressed patients.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
The antidepressant efficacy of trazodone has been shown to be significantly correlated to its steady‐state plasma levels, and previous work has shown some understanding of trazodone range of affinity for different receptors, at different doses, but without considering the different available formulations. Trazodone is commonly available as: immediate release (IR), prolonged release (PR), and once a day (OAD) tablets. The IR formulation has a rapid onset and short duration of action, whereas the PR formulation is characterized by an absorption boost as soon as it is administered and has a comparatively delayed maximum concentration (Cmax). Conversely, the OAD formulation provides a controlled release of trazodone over 24 h without the early high peak plasma concentration seen with the IR and PR formulations.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This work aims to identify the brain receptors reaching a threshold occupancy of 50% through static predictions and determine the occupancy versus time profile for those of interest following administration of short‐ and long‐acting trazodone formulations.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Brain receptor occupancy (RO) for key targets were predicted based on free drug concentrations, allowing for a physiologically relevant assessment of the different pathways affected by each formulation and dose.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
The presented physiologically‐based pharmacokinetic approach to assess RO can be used to guide formulation selection and dosing in clinical studies.  相似文献   
100.
In Italy, serogroup C meningococci of the clonal complex cc11 (MenC/cc11) have caused several outbreaks of invasive meningococcal disease (IMD) during the past 20 years. Between December 2019 and January 2020, an outbreak of six cases of IMD infected with MenC/cc11 was identified in a limited area in the northern part of Italy. All cases presented a severe clinical picture, and two of them were fatal. This report is focused on the microbiological and molecular analysis of meningococcal isolates with the aim to reconstruct the chain of transmission. It further presents the vaccination strategy adopted to control the outbreak. The phylogenetic evaluation demonstrated the close genetic proximity between the strain involved in this outbreak and a strain responsible for a larger epidemic that had occurred in 2015 and 2016 in the Tuscany Region. The rapid identification and characterisation of IMD cases and an extensive vaccination campaign contributed to the successful control of this outbreak caused by a hyperinvasive meningococcal strain.  相似文献   
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