43 research outputs found
Hedysarum coronarium-Based Green Composites Prepared by Compression Molding and Fused Deposition Modeling
In this work, an innovative green composite was produced by adding Hedysarum coronarium (HC) flour to a starch-based biodegradable polymer (Mater-Bi\uae, MB). The flour was obtained by grinding together stems, leaves and flowers and subsequently sieving it, selecting a fraction from 75 \ub5m to 300 \ub5m. Four formulations have been produced by compression molding (CM) and fused deposition modeling (FDM) by adding 5%, 10%, 15% and 20% of HC to MB. The influence of filler content on the processability was tested, and rheological, morphological and mechanical properties of composites were also assessed. Through CM, it was possible to obtain easily homogeneous samples with all filler amounts. Concerning FDM, 5% and 10% HC-filled composites proved also easily printable. Mechanical results showed filler effectively acted as reinforcement: Young\u2019s modulus and tensile strengths of the composites increased from 74.3 MPa to 236 MPa and from 18.6 MPa to 33.4 MPa, respectively, when 20% of HC was added to the pure matrix. FDM samples, moreover, showed higher mechanical properties if compared with CM ones due to rectilinear infill and fibers orientation. In fact, regarding the 10% HC composites, Young\u2019s modulus of the CM and FDM ones displayed a relative increment of 176% and 224%, respectively
Green Composites Based on Hedysarum coronarium with Outstanding FDM Printability and Mechanical Performance
The addition of natural scraps to biodegradable polymers has gained particular interest in recent years, allowing reducing environmental pollution related to traditional plastic. In this work, new composites were fabricated by adding 10% or 20% of Hedysarum coronarium (HC) flour to Poly (lactic acid) (PLA). The two formulations were first produced by twin screw extrusion and the obtained filaments were then employed for the fabrication of composites, either for compression molding (CM) or by fused deposition modeling (FDM), and characterized from a morphological and mechanical point of view. Through FDM it was possible to achieve dense structures with good wettability of the filler that, on the contrary, cannot be obtained by CM. The results indicate that the filler effectively acts as reinforcement, especially for FDM composites. The most remarkable enhancement was found in the flexural properties (+100% of modulus and ultimate strength), followed by tensile resistance and stiffness (+60%) and impact strength (+50%), whereas a moderate loss in tensile deformability was observed, especially at the highest loading. By adding HC to the polymeric matrix, it was possible to obtain a green, high-performance, and cost-effective composite, which could find applications for the fabrication of panels for furniture or the automotive industry
Influence of Branching on the Rheology, Filmability and Mechanical and Optical Properties of a Biodegradable and Compostable Co-Polyester
Over the last years, bio-based and biodegradable alternatives have gained considerable attention both of academic and of packaging industrial communities, driven by recent legislation and increasing awareness concerning environmental issues related to traditional plastic. However, it is often observed that packaging products made from bioplastics do not exhibit comparable performance to those produced using common non-biodegradable ones. The presence of long chain branching improves the processing behavior under elongational flow and, then, the filmability of low viscosity polymers such as polyesters. In this work it has been demonstrated that the presence of long chain branching in a bio-co-polyester, induced by the use of pentaerythritol in the synthesis a of poly(butylene adipate-co-butylene terephthalate), is able to dramatically change the rheological behavior of the linear chain polyester improving its filmability. The addition of branching lead to an increase of the elastic modulus and the tensile strength in branched polyester films if compared to the linear ones, while the elongation at break decreased. This is due to the answer of the branched polyester to the non-isothermal elongational flow that allows a better orientation of the macromolecules of the branched polyester. The film obtained with the branched polyester showed a decrease in clarity and a slight increase in haze if compared to linear one due to differences in the morphology of the two samples
Bacterial biofilms on biopolymeric sorbent supports for environmental bioremediation
Bioremediation encompasses a broad range of environmental biotechnology, which require
multidisciplinary approaches through implementation of innovative tools to the natural biological
process occurring in soil, water and air. Immobilization of hydrocarbon-degrading microorganisms
on biodegradable sorbent supports significantly promotes bioremediation processes. Recently
ecofriendly, low cost bioremediation devices based on polylactic acid (PLA) and polycaprolactone
(PCL) membranes hosting a biodegrading bacterial biofilms were obtained[1]. This work
investigates the higher effectiveness of immobilizing hydrocarbon-degrading bacteria compared to
that of planktonic cells. Soil hydrocarbon (HC) degrading Actinobacteria Nocardia cyriacigeorgica
strain SoB, Gordonia amicalis strain SoCg[2], and the marine hydrocarbonoclastic Alcanivorax
borkumensis strain AU3-AA-7[3] were immobilized on PLA and PCL membranes and tested on
hexadecane. The capacity of adhesion and proliferation of these biodegrading biofilms within
the biopolymers were evaluated at various time points (5, 10, 15, and 30 incubation days) using
scanning electron microscopy (SEM). The SEM images revealed that PLA and PCL nanofibers
were nearly completely covered by a complex three-dimensional bacterial film for all tested
strains. Quantification of total biomass (estimated as total dsDNA) confirmed biofilm growth up to
30 days of incubation. Crude oil biodegradation ability of biofilms-membranes systems, assessed
by Gas Chromatography-FID analysis, demonstrated the removal of over 60% of the oil after 5
days of incubation, outperforming free-living bacteria by 24%. Viable plate counts showed that
bacterial biofilms adsorbed on biopolymers were still viable after 30 days, indicating their potential
for long-term applications
Leg ulcer and osteomyelitis due to methicillin-susceptible Staphylococcus aureus infection after fracture repair treatment: a case highlighting the potential role of prostaglandin Eâ vasodilator
Prostaglandins appear to reduce biofilm formation and chronicization of infections, and stimulate a rapid and effective clearance of infecting micro-organisms. We report a case of recovery from methicillin-susceptible Staphylococcus aureus (MSSA) osteomyelitis after multidisciplinary management with antibiotics, anti-thrombotics and prostaglandin E1 (PGE1) vasodilator, in a patient with tibial plateau fracture repaired with internal fixation devices. A 47-year-old HIV-negative male with chronic ulcer on the proximal third of the left leg was admitted to the Orthopaedic Unit of the Orestano Clinic in Palermo, Italy, for suspected osteomyelitis. A biopsy of the skin ulcer and blood cultures were performed and resulted positive for MSSA. Labelled leukocyte scintigraphy confirmed osteomyelitis. No clinical improvement was observed after combined antibiotic treatment with rifampicin plus trimethoprim-sulfamethoxazole. The patient underwent a 4-day therapeutic cycle: PGE1 (alprostadil 60 mg/day IV) combined with nadroparin calcium plus gentamicin, followed by treatment with aminaftone plus sulodexide plus levofloxacin. At discharge, the patient's painful symptoms had completely resolved and the ulcer had cicatrized; recovery from osteomyelitis was confirmed by scintigraphy. This treatment protocol including PGE1 may result in a significant improvement in quality of life and functional status of patients with a reduction in direct and indirect costs and economic benefit for the National Health Service
Maggior rischio cardiometabolico nelle donne affette da Cushing, anche in assenza di una franca Sindrome Metabolica.
COMEPA (COVID-19 Medicina Policlinico Palermo): a study in hospitalized patients.
Coronavirus disease 2019 (COVID-19) has dramatically changed our lives. In the past months, hospitals were saturated of patients; therefore, it is still important to have simple and standardized prognostic factors and to evaluate the efficacy and safety of medications commonly used for COVID-19. We aimed to collect data of the patients hospitalized in Internal Medicine and Geriatrics Wards at the University Hospital (Policlinico) âP. Giacconeâ in Palermo, Italy (COMEPA, COVID-19 Medicina Policlinico Palermo), with the main purpose of finding prognostic tools that can be easily used in clinical practice in order to identify patients hospitalized for/with COVID-19 at higher risk of negative outcomes, such as mortality, transfer to Intensive Care Unit (ICU) and institutionalization, as well as evaluating the
efficacy/safety of medications commonly used for COVID-19. For reaching these aims, the medical records of approximately 600 patients will be recorded, having data on several parameters and including as outcomes mortality, ICU placement, institutionalization. With the COMEPA study, we therefore plan to update current literature, giving new data on prognostic factors and on the efficacy/safety of some medications used for COVID-19
The degree of urinary hypercortisolism is not correlated with the severity of cushingâs syndrome
Cushing syndrome (CS) is characterized by increased morbidity and mortality compared to the general population. However, there are patients who have moreclinical aggressive forms than others. Aim of the study is to evaluate whether the degree of hypercortisolism, defined by the number of times urinary free cortisol (UFC) levels exceed the upper limit of the normal range (ULN), is related to the worsening of phenotypic features, as well as metabolic and cardiovascular parameters, in a cohort of CS patients. A cross-sectional study was conducted on 192 patients with active CS, consecutively presenting at the outpatientsâ clinic of the University Hospitals of Ancona, Naples, and Palermo. Patients were grouped into mild (UFC not exceeding twice the ULN), moderate (2â5 times the ULN), and severe (more than 5 times the ULN) hypercortisolism. Thirty-seven
patients (19.3 %) had mild, 115 (59.8 %) moderate, and 40 (20.9 %) severe hypercortisolism. A significant trend of increase among the three groups was demonstrated for 8-, 16-, and 24-h serum cortisol levels (p.001) and serum cortisol after low dose of dexamethasone suppression test
(p = 0.001). No significant trend of increase was found regarding phenotype and comorbidities. The degree of hypercortisolism by itself does not appear to be a sufficient parameter to express the severity of CS. Therefore, estimating the severity of CS according to biochemical parameters
remains a challenge, while the clinical phenotype and the associated comorbidities might be more useful to assessing the severity of the CS
Preliminary results of citravesâą effects on low density lipoprotein cholesterol and waist circumference in healthy subjects after 12 weeks: A pilot open-label study
Appropriate monitoring and control of modifiable risk factors, such as the level of lowdensity lipoprotein cholesterol (LDL-C) and other types of dyslipidemia, have an important role in the prevention of cardiovascular diseases (CVD). Recently, various nutraceuticals with lipid-lowering effects have gained attention. In addition to the plant-derived bioactive compounds, recent studies suggested that plant cells are able to release small lipoproteic structures named extracellular vesicles (EVs). The interaction between EVs and mammalian cells could lead to beneficial effects through anti-inflammatory and antioxidant activities. The present study aimed to assess the safety of the new patented plant-based product citraVesâą, containing extracellular vesicles (EVs) from Citrus limon (L.) Osbeck juice, and to investigate its ability to modulate different CV risk factors in healthy subjects. A cohort of 20 healthy volunteers was recruited in a prospective open-label study. All participants received the supplement in a spray-dried formulation at a stable dose of 1000 mg/day for 3 months. Anthropometric and hematobiochemical parameters were analyzed at the baseline and after the follow-up period of 1 and 3 months. We observed that the supplement has an effect on two key factors of cardiometabolic risk in healthy subjects. A significant change in waist circumference was found in women after 4 (85.4 [79.9, 91.0] cm, p < 0.005) and 12 (85.0 [80.0, 90.0] cm, p < 0.0005) weeks, when compared to the baseline value (87.6 [81.7, 93.6] cm). No difference was found in men (baseline: 100.3 [95.4, 105.2] cm; 4 weeks: 102.0 [95.7, 108.3] cm; 12 weeks: 100.0 [95.3, 104.7] cm). The level of LDL-C was significantly lower at 12 weeks versus 4 weeks (p = 0.0064). Our study evaluated, for the first time, the effects of a natural product containing plant-derived EVs on modifiable risk factors in healthy volunteers. The results support the use of EV extracts to manage cardiometabolic risk factors successfully
Elevated blood Hsp60, its structural similarities and cross-reactivity with thyroid molecules, and its presence on the plasma membrane of oncocytes point to the chaperonin as an immunopathogenic factor in Hashimoto's thyroiditis
The role Hsp60 might play in various inflammatory and autoimmune diseases is under investigation, but little information exists pertaining to Hashimotoâs thyroiditis (HT). With the aim to fill this gap, in the present work, we directed our attention to Hsp60 participation in HT pathogenesis. We found Hsp60 levels increased in the blood of HT patients compared to controls. The chaperonin was immunolocalized in thyroid tissue specimens from patients with HT, both in thyrocytes and oncocytes (Hurthle cells) with higher levels compared to controls (goiter). In oncocytes, we found Hsp60 not only in the cytoplasm but also on the plasma membrane, as shown by double immunofluorescence performed on fine needle aspiration cytology. By bioinformatics, we found regions in the Hsp60 molecule with remarkable structural similarity with the thyroglobulin (TG) and thyroid peroxidase (TPO) molecules, which supports the notion that autoantibodies against TG and TPO are likely to recognize Hsp60 on the plasma membrane of oncocytes. This was also supported by data obtained by ELISA, showing that anti-TG and anti-TPO antibodies cross-react with human recombinant Hsp60. Antibody-antigen (Hsp60) reaction on the cell surface could very well mediate thyroid cell damage and destruction, perpetuating inflammation. Experiments with recombinant Hsp60 did not show stimulation of cytokine production by peripheral blood mononuclear cells from HT patients. All together, these results led us to hypothesize that Hsp60 may be an active player in HT pathogenesis via an antibody-mediated immune mechanism