604 research outputs found
Alpine landslide risk scenario: run-out modelling using a 3D approach
Rockslides of considerable volume developing on the flanks of narrow alpine valleys represent a significant hazard for the potential of river damming and consequent sudden discharge of water. A limestone rock mass of about 650,000 m3 endangers a portion of the upper course of Tagliamento River valley in north-eastern Italy. This section of the valley is prone to detachment of rock landslides due to its structural setting and it has a history of landslide damming: in the literature two huge events are widely documented and a third event is identified and described in this paper. The ancient detachment crown and the corresponding deposit can be observed in the portion of slope adjacent to the unstable rock mass. This paper deals with the run-out model of the unstable rock mass using a Smoothed Particles Hydrodynamics (SPH) model implemented in the DAN3D code. In order to select the appropriate material parameters, the ancient rockslide was back-analysed. Subsequently, the parameters were applied to the present unstable portion of the slope to determine the location and dimensions of the deposit that could be formed. It is demonstrated that the deposit has the potential to create a natural dam across the Tagliamento River that would form a 500,000 m3 lake. Although the lake will have limited dimensions, this would represent a very high risk for the downstream villages and infrastructures in case of a sudden collapse of the natural dam
Unified modeling of the mammalian and fish proton-dependent oligopeptide transporter PepT1
Electrophysiological and biophysical analyses were used to compare the partial and complete transport cycles of the intestinal oligopeptide transporter PepT1 among three species (seabass, zebrafish and rabbit). On the whole, the presteady-state currents of the fish transporters were similar to each other. Rabbit PepT1 differed from the fish transporters by having slower-decaying currents, and the charge vs. potential (Q/V) and time constant vs. potential (τ/V) curves shifted to more positive potentials. All of the isoforms were similarly affected by external pH, showing acidity-induced slowing of the transients and positive shifts in the Q/V and τ/V curves. Analysis of the pH-dependence of the unidirectional rates of the intramembrane charge movement suggested that external protonation of the protein limits the speed of this process in both directions. The complete cycle of the transporter was studied using the neutral dipeptide Gly-Gln. Michaelis-Menten analysis confirmed that, in all species, acidity significantly increases the apparent affinity for the substrate but does not strongly impact maximal transport current. Simulations using a kinetic model incorporating the new findings showed good agreement with experimental data for all three species, both with respect to the presteady-state and the transport currents
Eliciting Preferences for Clinical Follow-Up in Patients with Head and Neck Cancer Using Best-Worst Scaling.
OBJECTIVES: There are no commonly accepted standards for monitoring patients treated for head and neck cancer. The aim of this study was to assess patients' preferences for different aspects of follow-up. METHODS: A best-worst survey was conducted in a sample of head and neck cancer patients in clinical follow-up at the National Cancer Institute (Milan, Italy). Conditional logit regression with choice as the dependent variable was run to analyse the data. A covariate-adjusted analysis was performed in order to identify socio-demographic and clinical factors related to the selection of best-worst items. The participants were asked to report any difficulties encountered during the survey. RESULTS: A total of 143 patients, predominantly male (74%) and with a mean age of 58 years were enrolled in the survey. The strongest positive preference was expressed for a hospital-based program of physical examinations with frequency decreasing over time. Conversely, the lowest valued item was not performing any positron emission tomography (PET) scan during follow-up. Patients with high educational levels were more likely to value attending a primary care-based program and undergoing intensive radiological investigations. Other patient-specific variables significantly associated with the choice of items were employment and living status, time already spent in follow-up and number of treatments received. CONCLUSIONS: Overall, patients were more likely to choose an intensive follow-up scheme broadly consistent with the program currently administered by the hospital. There is little evidence of preference heterogeneity that might justify customized programs based on demographics. The best-worst scaling task appeared feasible for most participants
Reirradiation of head and neck squamous cell carcinomas: a pragmatic approach-part I: prognostic factors and indications to treatment.
INTRODUCTION
Reirradiation (reRT) of locally recurrent/second primary tumors of the head and neck region is a potentially curative treatment for patients not candidate to salvage surgery. Aim of the present study is to summarize available literature on both prognostic factors and indications to curative reRT in this clinical setting.
MATERIALS AND METHODS
A narrative review of the literature was performed on two topics: (1) patients' selection according to prognostic factors and (2) dosimetric feasibility of reRT. Postoperative reRT and palliative intent treatments were out of the scope of this work.
RESULTS
Patient-tumor and treatment-related prognostic factors were analyzed, together with dosimetric parameters concerning target volume and organs at risk. Based on available evidence, a stepwise approach has been proposed aiming to provide a useful tool to identify suitable candidates for curative reRT in clinical practice. This was then applied to two clinical cases, proposed at the end of this work.
CONCLUSION
A second course of RT in head and neck recurrence/second primary tumors is a personalized approach that can be offered to selected patients only in centers with expertise and dedicated equipment following a multidisciplinary team discussion
Quality of life changes over time and predictors in a large head and neck patients' cohort: secondary analysis from an Italian multi-center longitudinal, prospective, observational study-a study of the Italian Association of Radiotherapy and Clinical Oncology (AIRO) head and neck working group
Purpose: The present study examined the longitudinal trajectories, through hierarchical modeling, of quality of life among patients with head and neck cancer, specifically symptoms burden, during radiotherapy, and in the follow-up period (1, 3, 6, and 12 months after completion of radiotherapy), through the M.D. Anderson Symptom Inventory Head and Neck questionnaire, formed by three factors. Furthermore, analyses were conducted controlling for socio-demographic as well as clinical characteristics. Methods: Multi-level mixed-effects linear regression was used to estimate the association between quality of life and time, age, gender, household, educational level, employment status, ECOG performance status, human papilloma virus (HPV) status, surgery, chemotherapy, alcohol intake, and smoking. Results: Among the 166 participants, time resulted to be a predictor of all the three questionnaire factors, namely, general and specific related symptoms and interference with daily life. Moreover, regarding symptom interference with daily activities factor, HPV-positive status played a significant role. Considering only HPV-negative patients, only time predicted patients' quality of life. Differently, among HPV-positive patients, other variables, such as gender, educational level, alcohol use, surgery, age at diagnosis, employment status, and ECOG status, resulted significant. Conclusion: It was evident that quality of life of patients with head and neck cancer declined during RT, whereas it slowly improved after ending treatment. Our results clarified the role of some socio-demographic and clinical variables, for instance, HPV, which would allow to develop treatments tailored to each patient
Restoration of CFTR function in patients with cystic fibrosis carrying the F508del-CFTR mutation
<div><p>Restoration of BECN1/Beclin 1-dependent autophagy and depletion of SQSTM1/p62 by genetic manipulation or autophagy-stimulatory proteostasis regulators, such as cystamine, have positive effects on mouse models of human cystic fibrosis (CF). These measures rescue the functional expression of the most frequent pathogenic CFTR mutant, F508del, at the respiratory epithelial surface and reduce lung inflammation in <i>Cftr<sup>F508del</sup></i> homozygous mice. Cysteamine, the reduced form of cystamine, is an FDA-approved drug. Here, we report that oral treatment with cysteamine greatly reduces the mortality rate and improves the phenotype of newborn mice bearing the <i>F508del-CFTR</i> mutation. Cysteamine was also able to increase the plasma membrane expression of the F508del-CFTR protein in nasal epithelial cells from <i>F508del</i> homozygous CF patients, and these effects persisted for 24 h after cysteamine withdrawal. Importantly, this cysteamine effect after washout was further sustained by the sequential administration of epigallocatechin gallate (EGCG), a green tea flavonoid, both <i>in vivo</i>, in mice, and <i>in vitro</i>, in primary epithelial cells from CF patients. In a pilot clinical trial involving 10 <i>F508del-CFTR</i> homozygous CF patients, the combination of cysteamine and EGCG restored BECN1, reduced SQSTM1 levels and improved CFTR function from nasal epithelial cells <i>in vivo</i>, correlating with a decrease of chloride concentrations in sweat, as well as with a reduction of the abundance of <i>TNF/TNF-alpha (tumor necrosis factor)</i> and <i>CXCL8</i> (<i>chemokine [C-X-C motif] ligand 8</i>) transcripts in nasal brushing and TNF and CXCL8 protein levels in the sputum. Altogether, these results suggest that optimal schedules of cysteamine plus EGCG might be used for the treatment of CF caused by the <i>F508del-CFTR</i> mutation.</p></div
The Multidisciplinary Management of Cutaneous Squamous Cell Carcinoma: A Comprehensive Review and Clinical Recommendations by a Panel of Experts
Simple Summary Cutaneous squamous cell carcinoma is one of the most common forms of cancer. Although most cases are cured with surgical excision, a few tumors are associated with a high risk of local or distant relapse; therefore, it is relevant to identify high-risk lesions among all other low-risk CSCCs for the proper diagnostic and therapeutic management. Chemotherapy achieves mostly short-lived responses that do not lead to a curative effect and are associated with severe toxicities. Recently, PD-1 inhibitor cemiplimab was approved by the regulatory authorities for the treatment of advanced cutaneous squamous cell carcinoma; subsequently, the anti-PD-1 agent pembrolizumab received the approval by the FDA only in the same setting. Here, we provide a literature review and clinical recommendations by a panel of experts regarding the diagnosis, treatment, and follow-up of cutaneous squamous cell carcinoma. Cutaneous squamous cell carcinomas (CSCC) account for about 20% of all keratinocyte carcinomas, which are the most common form of cancer. Heterogeneity of treatments and low mortality are a challenge in obtaining accurate incidence data and consistent registration in cancer registries. Indeed, CSCC mostly presents as an indolent, low-risk lesion, with five-year cure rates greater than 90% after surgical excision, and only few tumors are associated with a high-risk of local or distant relapse; therefore, it is particularly relevant to identify high-risk lesions among all other low-risk CSCCs for the proper diagnostic and therapeutic management. Chemotherapy achieves mostly short-lived responses that do not lead to a curative effect and are associated with severe toxicities. Due to an etiopathogenesis largely relying on chronic UV radiation exposure, CSCC is among the tumors with the highest rate of somatic mutations, which are associated with increased response rates to immunotherapy. Thanks to such strong pre-clinical rationale, clinical trials led to the approval of anti-PD-1 cemiplimab by the FDA (Food and Drug Administration) and EMA (European Medicines Agency), and anti-PD-1 pembrolizumab by the FDA only. Here, we provide a literature review and clinical recommendations by a panel of experts regarding the diagnosis, treatment, and follow-up of CSCC
Insight Into the Distribution of Staphylococci and Their Enterotoxins in Cheeses Under Natural Conditions
Staphylococcal food poisoning outbreaks are a major cause of food-borne illness in the European Union and their notification has been mandatory since 2005. Criteria for the enumeration of coagulase-positive Staphylococci (CPS) and the detection of staphylococcal enterotoxins (SEs) in cheese have been set down in Commission Regulation EC 2073/2005. Currently, few information are available about the distribution of SEs in naturally contaminated cheeses, including raw-milk and artisanal dairy products. The aim of this study was therefore to investigate at both the CPS enumeration and the succession of the enterotoxigenic Staphylococcus aureus and produced enterotoxins levels on the rind and the core of a raw-milk semi-hard cheese, produced on farm. The study has been conducted in three steps: (I) seven wheels at different time of ripening where tested for the presence of SEs. (II) from each wheel, four portions were subsequently sampled from four different areas (peripheral rind, central rind, peripheral core and central core). (III) two cheese wheels, characterized by the highest and lowest CPS numbers and SEs quantification, based on the second step of the study, were further analyzed. A significant difference has been observed in the distribution of CPS and SEs in the four areas sampled, irrespectively of the batch and the time of ripening. The results of this study provided a set of previously unknown information on the influence of natural conditions on the distribution of CPS and SEs thereof in the cheese matrix, filling a gap in the understanding of SEs biosynthesis process
Assessment of organic and inorganic pollution in an alluvial soil of the Riachuelo River, Buenos Aires, Argentina
Se evaluó el suelo en un área urbana a orillas del río Riachuelo, en la ciudad de Buenos Aires. Las muestras superficiales (0-25 cm) fueron tomadas en transectas perpendiculares a la costa. Se detectó la presencia de metales pesados y de compuestos orgánicos contaminantes. Los rangos de valores obtenidos para los metales fueron: 1-5 mg/kg de cadmio, 4-23 mg/kg de arsénico, 25-497 mg/kg de cobre, 8-43 mg/kg de níquel, 5-503 mg/kg de cromo y 21-235 mg/kg de plomo. El cadmio, el cobre, el arsénico y el cromo superaron los valores considerados no tolerables por la ley 24051 de residuos peligrosos para el uso más restrictivo. El tolueno fue el compuesto orgánico predominante. La concentración de metales e hidrocarburos disminuyó (aunque en diferente proporción) al alejarse unos cuatro metros desde la línea costera hacia el interior. Las variables edáficas también cambiaron sus valores en una estrecha distancia: el pH aumentó y el carbono total disminuyó entre la ribera y 4 m tierra adentro. El cinc y el cobre extraídos con DTPA (fracción que comprende a los compuestos más solubles, de mayor actividad) alcanzaron valores de 12.5-47.2 mg/kg y 2.99-14.46 mg/kg, respectivamente, muy superiores a los registrados en suelos agrícolas de origen similar. La fuente de estos metales y contaminantes orgánicos es el agua del río, y se evidencia el efecto protector de la ribera frente a la acumulación de desechos con efecto contaminante potencial. La combinación de distintos metales pesados en exceso y productos orgánicos de riesgo para la salud convierten al sitio en un lugar no apto para la recreación. La remediación o saneamiento es indispensable para minimizar los riesgos para la población que frecuenta el sitio.An evaluation of soils from a coastline sector of the Riachuelo River, in Buenos Aires City, was carried out. Superficial soil samples (0-25 cm depth) were taken on perpendicular transects from the river to inland, and analyzed to identify organic and inorganic contaminants. Ranges of values for metals were: 1-5 mg/kg for cadmium, 4-23 mg/kg for arsenic, 25-497 mg/kg for copper, 8-43 mg/kg for nickel, 5-503 mg/kg for chromium, and 21-235 mg/kg for lead. Cadmium, arsenic, copper and chromium levels were higher than those considered dangerous by the Argentine hazardous wastes law 24051. Toluene was the most important organic pollutant identified. Concentration of metals and organic pollutant decreased sharply from the coastal river line into the land. Soil characteristics also changed in a short distance: pH increased and total carbon decreased along the transect from the coast into the land. Zinc and copper extracted by DTPA reached 12.5-47.2 mg/kg and 2.99-14.46 mg/kg, respectively, higher values than those usually found in this type of soils. Metals and hydrocarbons come from the river. Four meters far from the riverside, the concentration of metals diminishes to acceptable values. This variation shows the protective effect of the riverside. Remediation to make public access possible without risk for the population is recommended
Ischemic wound revascularization by the stromal vascular fraction relies on host-donor hybrid vessels
Nonhealing wounds place a significant burden on both quality of life of affected patients and health systems. Skin substitutes are applied to promote the closure of nonhealing wounds, although their efficacy is limited by inadequate vascularization. The stromal vascular fraction (SVF) from the adipose tissue is a promising therapy to overcome this limitation. Despite a few successful clinical trials, its incorporation in the clinical routine has been hampered by their inconsistent results. All these studies concluded by warranting pre-clinical work aimed at both characterizing the cell types composing the SVF and shedding light on their mechanism of action. Here, we established a model of nonhealing wound, in which we applied the SVF in combination with a clinical-grade skin substitute. We purified the SVF cells from transgenic animals to trace their fate after transplantation and observed that it gave rise to a mature vascular network composed of arteries, capillaries, veins, as well as lymphatics, structurally and functionally connected with the host circulation. Then we moved to a human-in-mouse model and confirmed that SVF-derived endothelial cells formed hybrid human-mouse vessels, that were stabilized by perivascular cells. Mechanistically, SVF-derived endothelial cells engrafted and expanded, directly contributing to the formation of new vessels, while a population of fibro-adipogenic progenitors stimulated the expansion of the host vasculature in a paracrine manner. These data have important clinical implications, as they provide a steppingstone toward the reproducible and effective adoption of the SVF as a standard care for nonhealing wounds
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