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Obesity: a disease of the ponderostat and the regulation of energy balance
No full text: Energy balance and thermodynamic laws regulate body weight. Therefore, obesity must occur over a sufficiently long period of time in which energy intake exceeds energy expenditure. It is clear that a strict application of the law of energy balance cannot fully explain what is observed in real life. One possible hypothesis is that some individuals may have an energy-sparing metabolism, predisposing them to obesity. Furthermore, energy balance can be regulated to maintain body weight within a fixed individual range, a set point, which is influenced by genetic or epigenetic factors. An energy balance regulator, the ponderostat, may be able to increase or decrease both energy expenditure and energy intake, depending on food availability (e.g., periods of famine or low-calorie diet, periods of overeating), to maintain body weight within the set point. The ponderostat is regulated by a complex neuroendocrine system that includes central structures located in the frontal cortex, hypothalamus, and diencephalic region, with peripheral afferents and efferents. Therefore, in many cases, obesity could be considered the consequence of a dysregulated ponderostat. This narrative review proposes a unifying perspective that considers obesity as a biological condition with an abnormal set point and dysregulated energy balance due to abnormalities in ponderostat function. Current and future antiobesity pharmacological treatments may be considered curative for ponderostat dysregulation
Assessment of Seismic Vulnerability of Segmental Bridges with Tall Piers by Static Non-linear Analysis
No full textPrestressed concrete segmental bridges, constructed by cantilevering with medium to large span lengths during the 1950s to 1970s and still in service, are now reaching the end of their nominal service life and were designed according to outdated Technical Codes. Therefore, the seismic assessment of these bridges must take into account the roles of piers, bearings, and drop-in spans, which are susceptible to beam pounding. The paper focuses on the seismic vulnerability assessment of bridges with a first approach through using response spectrum analysis; afterwards, the efficiency of various non-linear static analysis procedures is compared with the results from non-linear response history analysis, demonstrating that bearings play a crucial role in evaluating seismic vulnerability to longitudinal motion, especially for the segmental framed scheme with drop-in spans
Recensione di Mapelli, Giovanna, El discurso de los pediatras en las redes sociales, Berlín: Peter Lang, 2024, 200 pp., ISBN. 978-3-631-92438-9
No full textReseña del volumen Mapelli, Giovanna, El discurso de los pediatras en las redes sociales, Berlín: Peter Lang, 2024
Stable Multi-Wavelength Resonant Metal-dielectric Hybrid Nanostructure in the Infrared Range
No full textPlasmonic nanostructures typically exhibit shifts in their resonant wavelength in response to changes in the refractive index of the surrounding medium. This limits their applications in scenarios requiring stable optical resonances. Here we present
a metallic-dielectric hybrid metasurface that exhibits stable multi-wavelength resonance even if the refractive index of its surrounding varies. To quantitatively evaluate the stability of the optical response, we introduce a stability factor FS = Δn/Δλ. Here, Δn and Δλ represent variation of refractive index and shift of the resonant wavelength, respectively. A larger factor indicates better stability. The factor reaches 5 RIU/μm when silicon is employed as the central dielectric and increases to 33.3
RIU/μm when Bi 2 Te3 is utilized instead. The proposed innovative structure has potential applications in the development of substrates for in-vitro cell cultivation. Under broadband light illumination, it stably absorbs light at specific wavelengths,
creating a consistent optical microenvironment leading to cell growth. It can find potential applications in precise control of various cellular processes, including metabolism and differentiation. It potentially brings a paradigm shift in the fields of cell based research and regenerative medicine, opening up new avenues for scientific exploration and therapeutic advancements
Comparison of the predictive performance of Cumulative Illness Rating Scale, Charlson Comorbidity Index and COMCOLD Index for moderate-to-severe exacerbations in elderly subjects with chronic obstructive pulmonary disease
No full textBackground and objective: Chronic Obstructive Pulmonary Disease (COPD) is frequently associated with multiple comorbidities that influence clinical outcomes. This study aimed to compare the predictive performance of the Cumulative Illness Rating Scale (CIRS) with the Charlson Comorbidity Index (CCI) and COMCOLD Index for moderate-to-severe COPD exacerbations. Materials and methods: We conducted a prospective observational study involving 200 COPD patients followed for 52 weeks. CIRS indices (Total Score, Severity Index, Comorbidity Index), CCI, and COMCOLD were calculated at baseline. The primary outcome was time-to-first moderate-to-severe exacerbation. Cox regression analyses and time-dependent receiver operating characteristic curves were used to assess prognostic performance at 12, 24, and 52 weeks. Results: During follow-up, 66 patients (33%) experienced at least one moderate-to-severe exacerbation. All CIRS indices demonstrated significant correlations with respiratory parameters and symptom burden. In crude models, CIRS indices were significantly associated with exacerbation risk (CIRS-TS: HR 1.11, 95%CI 1.06-1.16; CIRS-SI: HR 1.16, 95%CI 1.09-1.23; CIRS-CI: HR 1.37, 95%CI 1.20-1.56; all p < 0.001), maintaining significance after adjustment for clinical covariates. CIRS indices demonstrated superior discriminative performance compared to CCI and COMCOLD, with CIRS-SI achieving the highest time-dependent AUC values across all timepoints (0.704, 0.679, and 0.778 at 12, 24, and 52 weeks, respectively). Conclusion: CIRS provides superior prognostic accuracy compared to established comorbidity indices in identifying COPD patients at increased risk of exacerbations. These findings highlight the clinical relevance of incorporating a comprehensive, severity-weighted comorbidity assessment in COPD management, supporting the concept of COPD as a complex, multisystem disorder requiring an integrated approach to care. KEY MESSAGES 1. In elderly patients with COPD, CIRS provided superior prognostic accuracy for moderate-to-severe exacerbations compared with the Charlson Comorbidity Index and COMCOLD; 2. The prognostic advantage of CIRS likely derives from its comprehensive, severity-weighted assessment of multimorbidity across multiple organ systems; 3. Incorporating multidimensional comorbidity evaluation, such as CIRS, into clinical practice may improve risk stratification and support more personalized COPD management
Novel adiposity indices and their role in identifying left ventricular hypertrophy among hypertensive individuals undergoing echocardiography
No full textBackground and aims: While body mass index (BMI) is the most used measure of adiposity, it does not account for fat distribution. Novel indices, such as A Body Shape Index (ABSI) and Body Roundness Index (BRI), may better reflect cardiometabolic risk. However, their association with subclinical cardiac damage, particularly left ventricular hypertrophy (LVH), remains unclear. The aim of this study was to evaluate the association between novel adiposity indices (ABSI and BRI) and left ventricular mass (LVM) assessed by echocardiography in a large cohort of patients with hypertensive. Methods and results: We conducted a cross-sectional study including 724 hypertensive adults who underwent standardized anthropometric and echocardiographic assessments. Adiposity indices (BMI, waist circumference, ABSI, and BRI) were calculated, and left ventricular mass was indexed to body surface area and height2.7. Correlations and multivariate analyses were performed, and receiver operating characteristic (ROC) curves were used to assess diagnostic performance. All adiposity indices were significantly higher in individuals with LVH. BRI showed the strongest correlation with LVMH2.7 (r = 0.423), particularly in women. In multivariate analysis, BRI remained significantly associated with LVMH2.7 in both sexes, while ABSI was not independently associated in men. ROC curve analysis demonstrated that BRI had the highest diagnostic accuracy for identifying LVH, outperforming BMI and ABSI, especially when LVH was defined using LVMH2.7. Conclusions: BRI outperformed traditional and novel adiposity indices in identifying LVH in hypertensive patients, particularly when LVM was indexed to height2.7. Given its superior diagnostic performance, BRI may represent a valuable tool in cardiovascular risk stratification, though further studies are warranted
Exploring the Biochemical Mechanism Beyond the Cytotoxic Activity of Sesquiterpene Lactones from Sicilian Accession of Laserpitium siler Subsp. siculum (Spreng.) Thell
No full textLaserpitium siler subsp. siculum (Apiaceae) is a Mediterranean plant with a long history of
traditional medicinal use. In this study, the chemical composition and anticancer potential
of three novel (and one new to the genus) sesquiterpene lactones (SLs) isolated from its
roots were investigated. The structural characterization, carried out through NMR and
HPLC-MS analyses, identified unique guaianolide-type lactones. The biological activity of
these compounds was evaluated in vitro using MDA-MB-231 cells, a triple-negative breast
cancer (TNBC) cell line. Cell viability assays demonstrated that all SLs tested reduced
TNBC cell viability in a dose- and time-dependent manner, with SL-1 exhibiting the highest
cytotoxicity. Light microscopy analyses and acridine orange/ethidium bromide staining
confirmed the induction of apoptotic cell death, further supported byWestern blot analyses
showing caspase-3 activation and PARP-1 cleavage. Additional experiments indicated that
SL-1 induced oxidative stress, as evidenced by increased ROS production and upregulation
of the levels of the antioxidant enzymes MnSOD and HO-1. Moreover, JC-1 staining
andWestern blot analyses revealed mitochondrial membrane depolarization as well as a
significant reduction in VDAC-1 expression, suggesting mitochondrial dysfunction as a
key event in the cytotoxic mechanism. These findings highlight L. siler subsp. siculum as
a promising source of bioactive compounds with anticancer potential. The ability of its
sesquiterpene lactones to induce oxidative stress and mitochondrial impairment provides
new insights into their mode of action, supporting further research into their therapeutic
applications for TNBC treatment
Policy Innovation for Public Value Creation: Insights from Dynamic Performance Governance in Addressing Rural Depopulation
No full textCounteracting rural depopulation requires that public sector organizations address wicked problems by adopting innovative policies to create public value. Traditional and linear performance management methods may not be able to solve local problems because they fail to represent the socio-economic, cultural, and ecological subsystems’ dynamic complexity. This contribution examines the Sambuca di Sicilia (Italy) local administration’s One-Euro House Project to counteract rural depopulation by enhancing quality of life and economic dynamism through the Dynamic Performance Governance framework. Such an approach enables the support of innovative policy solutions to tackle wicked problems and pursue sustainable community outcomes, thereby creating public value
