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1.
Heliyon ; 10(5): e26709, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38439845

ABSTRACT

The selectivity of a novel chemosensor, based on a modified nitrobenzofurazan referred to as NBD-Morph, has been investigated for the detection of heavy metal cations (Co2+, Pb2+, Mg2+, Ag+, Cu2+, Hg2+, Ni2+, and Zn2+). The ligand, 4-morpholino-7-nitrobenzofurazan (NBD-Morph), was characterized using spectroscopic techniques including FT-IR and 1H NMR. Vibrational frequencies obtained from FT-IR and proton NMR (1H) chemical shifts were accurately predicted employing the density functional theory (DFT) at the B3LYP level of theory. Furthermore, an examination of the structural, electronic, and quantum chemical properties was conducted and discussed. DFT calculations were employed to explore the complex formation ability of the NBD-Morph ligand with Co2+, Pb2+, Mg2+, Ag+, Cu2+, Hg2+, Ni2+, and Zn2+ metal cations. The comparison of adsorption energies for all possible conformations reveals that NBD-Morph exhibits sensitivity and selectivity towards metal ions, including Pb2+, Cu2+, Ag+, and Ni2+. However, an assessment of their reactivity using QTAIM topological parameters demonstrated the ligand's greater complexation ability toward Cu2+ or Ni2+ than those formed by Pb2+ or Ag+. Additionally, molecular electrostatic potential (MEP), Hirshfeld surfaces, and their associated 2D-fingerprint plots were applied to a detailed study of the inter-molecular interactions in NBD-Morph-X (X = Pb2+, Cu2+, Ag+, Ni2+) complexes. The electron localization function (ELF) and the localized-orbital locator (LOL) were generated to investigate the charge transfer and donor-acceptor interactions within the complexes. Electrochemical analysis further corroborates the theoretical findings, supporting the prediction of NBD-Morph's sensory ability towards Ni2+ metal cations. In conclusion, NBD-Morph stands out as a promising sensor for Ni2+.

2.
ACS Omega ; 9(1): 1029-1041, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38222547

ABSTRACT

In this study, we examined the influence of an external electric field applied in two directions: horizontal (X-axis) and vertical (Y-axis) on the electronic and vibrational properties of a field-effect molecular switch, denoted as M. We employed density functional theory and quantum theory of atoms in molecules for this analysis. The current-voltage (I-V) characteristic curve of molecular switch system M was computed by applying the Landauer formula. The results showed that the switching mechanism depends on the direction of the electric field. When the electric field is applied along the X-axis and its intensity is around 0.01 au, OFF/ON switching mechanisms occur. By utilizing electronic localization functions and localized-orbital locator topological analysis, we observed significant intramolecular electronic charge transfer "back and forth" in Au-M-Au systems when compared to the isolated system. The noncovalent interaction revealed that the Au-M-Au complex is also stabilized by electrostatic interactions. However, if the electric field is applied along the Y-axis, a switching mechanism (OFF/ON) occurs when the electric field intensity reaches 0.008 au. Additionally, the local electronic phenomenological coefficients (Lelec) of this field-effect molecular switch were determined by using the Onsager phenomenological approach. It can also be predicted that the molecular electrical conductance (G) increases as Lelec increases. Finally, the electronic and vibrational properties of the proposed models M and Au-M-Au exhibit a powerful switching mechanism that may potentially be employed in a new generation of electronic devices.

3.
Sci Rep ; 13(1): 22984, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38151497

ABSTRACT

The variations in the distribution of solar radiation due to the ~ 105 years Milankovitch cycle, which is connected to the Earth eccentricity variation, cannot explain the sharp drop in temperature of 6 °C ÷ 10 °C that marks the transition from the interglacial to the glacial age registered in the last ~ 5.5 106 years temperature variation behavior. More specifically, neglecting other effects, only a temperature variation of 0.2 °C ÷ 0.3 °C can be attributed to this cycle and, therefore, positive feedback effects should be taken into account to explain the registered effect. In the present work, a comparative Wavelet-Fourier analysis of the Vostok recontructed temperature record, for which different sampling steps are taken into account, is performed. Then, a study of exponential feedback effects within a climate parametric resonance model is dealt and discussed. The obtained findings put into evidence an exponential amplification of the temperature variation from the interglacial to the glacial age supporting the hypothesis that the system energization be connected to periodic variations in the internal solar system parameters. More in details, it is shown that, following the parametric resonance climate model, even small oscillations increase over time proportionally to the system energy itself, i.e. exponentially, and hence, a series of connected resonances is able to energize the climate system.

4.
Microorganisms ; 11(7)2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37513014

ABSTRACT

We report the ability of the crude biosurfactant (BS B3-15), produced by the marine, thermotolerant Bacillus licheniformis B3-15, to hinder the adhesion and biofilm formation of Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213 to polystyrene and human cells. First, we attempted to increase the BS yield, optimizing the culture conditions, and evaluated the surface-active properties of cell-free supernatants. Under phosphate deprivation (0.06 mM) and 5% saccharose, the yield of BS (1.5 g/L) increased by 37%, which could be explained by the earlier (12 h) increase in lchAA expression compared to the non-optimized condition (48 h). Without exerting any anti-bacterial activity, BS (300 µg/mL) prevented the adhesion of P. aeruginosa and S. aureus to polystyrene (47% and 36%, respectively) and disrupted the preformed biofilms, being more efficient against S. aureus (47%) than P. aeruginosa (26%). When added to human cells, the BS reduced the adhesion of P. aeruginosa and S. aureus (10× and 100,000× CFU/mL, respectively) without altering the epithelial cells' viability. As it is not cytotoxic, BS B3-15 could be useful to prevent or remove bacterial biofilms in several medical and non-medical applications.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 301: 122939, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37285745

ABSTRACT

The present work aims at exploring the high electrophilic character of 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) toward the morpholine group by an SNAr reaction in acetonitrile or water (thereafter referred to as NBD-Morph). The electron-donating ability of the morpholine causes intra-molecular charge transfer (ICT). In this report, we present a comprehensive study on the optical characteristics using UV-Vis, photoluminescence (cw-PL) and its time-resolved (TR-PL) to determine the properties of the emissive intramolecular charge transfer (ICT) in the NBD-Morph donor-acceptor system. An exhaustive theoretical investigation utilizing the density functional theory (DFT) and its extension TD-DFT methods is an essential complement of experiments to rationalize and understand the molecular structure and related properties. The findings from QTAIM, ELF, and RDG analyses establish that the bonding between morpholine and NBD moieties is of the electrostatic or hydrogen bond type. In addition, the Hirshfeld surfaces have been established to explore the types of interactions. Further, the non-linear optical (NLO) responses of the compound have been examined. The structure-property relationships obtained through the combined experimental and theoretical offer valuable insights for designing efficient NLO material.


Subject(s)
Benzofurans , Molecular Structure , Benzofurans/chemistry
6.
Int J Mol Sci ; 24(3)2023 Jan 29.
Article in English | MEDLINE | ID: mdl-36768887

ABSTRACT

The main aim of the present paper is to characterize the hydration properties of glucose and the hydrogen bond network in glucose-water mixtures. For these purposes, temperature scans on ten concentration values of glucose-water mixtures were performed by means of Fourier Transform InfraRed (FTIR) spectroscopy. More specifically, in order to get this information an analysis of the intramolecular OH stretching mode, investigating the 3000-3700 cm-1 spectral range, was performed by means of an innovative approach based on the evaluation of the Spectral Distance (SD). The adopted procedure allows evaluating the glucose hydration number as well as characterizing the temperature behavior of the hydrogen bond network in the glucose-water mixtures. The obtained results for the hydration number are in excellent agreement with literature data and suggest the existence of a particular concentration value for which the hydrogen bond network shows a maximum strength.


Subject(s)
Glucose , Water , Temperature , Water/chemistry , Spectrophotometry, Infrared/methods , Spectroscopy, Fourier Transform Infrared/methods , Hydrogen Bonding
7.
Molecules ; 27(24)2022 Dec 10.
Article in English | MEDLINE | ID: mdl-36557893

ABSTRACT

Infrared spectroscopy measurements were performed on Lysozyme aqueous solutions also in the presence of PolyEthylene Glycol (PEG 400) as a function of an increasing temperature from T = 27 °C to 90 °C, and, successively in sequence, by decreasing temperatures from T = 90 °C to 27 °C. Data were analyzed by evaluating the spectral difference with respect to the initial spectrum collected at 27 °C. This procedure allows to quantitatively evaluate the thermal restraint related to the thermal scan from T = 27 °C to 90 °C, as well as to introduce a spectral resilience concerning the entire increasing and decreasing thermal paths which allow to highlight the bioprotectant effectiveness of low molecular weight PEG. In particular, the main purpose of the present work is to highlight the effects of a thermal treatment on a mixture of Lysozyme/water and of Lysozyme/water/PEG 400 during an increasing temperature scan, and then after a successive decreasing temperature scan, in order to highlight the bioprotectant role of PEG 400. On that score, an evaluation of the spectral distances of the registered spectra as a function of increasing and decreasing temperatures has been performed and analyzed.


Subject(s)
Muramidase , Water , Muramidase/chemistry , Water/chemistry , Temperature , Polyethylene Glycols/chemistry , Solutions
8.
Molecules ; 27(19)2022 Sep 24.
Article in English | MEDLINE | ID: mdl-36234846

ABSTRACT

Creatine is a very popular amino acid widely utilized in the sports world due to its functions mainly related to muscle building and increasing performance. The present work investigates the behavior of creatine aqueous solutions and of creatine aqueous in the presence of trehalose as a function of time changes by means of Infrared spectroscopy. Infrared spectra have been gathered and studied over time for both the full spectrum and the intramolecular OH-stretching region for the two mixtures. This latter region was studied more specifically using a cutting-edge technique called Spectral Distance (SD). From this analysis of the spectral features of the investigated samples, it emerges that trehalose has a significant stabilizing effect on creatine aqueous solutions.


Subject(s)
Creatine , Trehalose , Amino Acids , Solutions , Spectroscopy, Fourier Transform Infrared/methods , Trehalose/chemistry , Water/chemistry
9.
Materials (Basel) ; 15(17)2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36079369

ABSTRACT

The surfactin-like lipopeptide (BS-SBP3) and the exopolysaccharide (EPS-SBP3) produced by the polyextremophilic Bacillus horneckiae SBP3 (DSM 103063) have been recently described as valuable biopolymers useful in biotechnological applications. To investigate the hydrating capabilities of BS-SBP3 and EPS-SBP3, here we evaluated (i) their wetting properties, measuring the contact angle; (ii) their moisture uptake abilities using the gravimetric method; and (iii) their hydrating states (from 0 to 160% w/w of water content) using ATR-FTIR spectroscopy. BS-SBP3 reduced the water contact angle on a hydrophobic surface from 81.7° to 51.3°, whereas the contact angle in the presence of EPS-SBP3 was 72.9°, indicating that BS-SBP3 improved the wettability of the hydrophobic surface. In the moisture uptake tests, EPS-SBP3 absorbed more water than BS-SBP3, increasing its weight from 10 mg to 30.1 mg after 36 h of 100% humidity exposure. Spectral distance and cross-correlation analyses were used to evaluate the molecular changes of the two biopolymers during the hydration process. As the water concentration increased, BS-SBP3 spectra changed in intensity in the two contributions of the OH-stretching band named "closed" and "open" (3247 and 3336 cm-1, respectively). Differently, the spectra of EPS-SBP3 exhibited a broader peak (3257 cm-1), which shifted at higher water concentrations. As evaluated by the spectral distance and the wavelet cross-correlation analysis, the OH-stretching bands of the BS-SBP3 and EPS-SBP3 changed as a function of water content, with two different sigmoidal trends having the inflection points at 80% and 48%, respectively, indicating peculiar water-properties of each biopolymer. As wetting agents, these biopolymers might replace industrially manufactured additives in agriculture and the food and cosmetic industries.

10.
Materials (Basel) ; 15(12)2022 Jun 18.
Article in English | MEDLINE | ID: mdl-35744387

ABSTRACT

Glutamine plays a significant role in several basic metabolic processes and is an important regulator of heat shock protein response. The present work is focused on the analysis of the thermal response of aqueous solutions of Glutamine and aqueous solutions of Glutamine in the presence of Trehalose by means of infrared absorption technique. The performed study shows how in the case of a multicomponent system, characterized by a huge number of spectral contributions whose assignment are questionable, the Spectral Distance (SD) and the Cross Wavelet Correlation (XWT) approaches are able to furnish explanatory parameters that can characterize the variations in the spectra behaviour, which is an efficient tool for quantitative comparisons. With this purpose, the analysis has been performed by evaluating the SD and the XWT parameters for the whole investigated spectral range, i.e., 4000-400 cm-1, for scans collected as a function of temperature in the range 20 °C ÷ 60 °C both for Glutamine/Water compounds and for Glutamine /Water/Trehalose mixtures. By means of these analyses, it is found that in aqueous solutions of Glutamine, with respect to aqueous solutions of Glutamine in the presence of Trehalose, the SD and XWT temperature trends follow a linear behaviour where the angular coefficient for Glutamine /Water/Trehalose compounds are lower than that of the Glutamine-Water system in both cases. The obtained findings suggest that Trehalose stabilizes Glutamine against heat treatment.

11.
J Neural Transm (Vienna) ; 129(3): 287-293, 2022 03.
Article in English | MEDLINE | ID: mdl-35024950

ABSTRACT

The association between dyslipidemia and cognitive performance in Parkinson's disease (PD) patients still needs to be clarified. Aim of the study was to evaluate the presence of possible associations between serum lipids fractions and executive dysfunction also exploring the sex-specific contribute of lipids level on cognition. Patients from the PACOS cohort, who underwent a complete serum lipid profile measures (total cholesterol-TC, low-density lipoprotein cholesterol-LDL, high-density lipoprotein cholesterol-HDL and triglycerides-TG) were selected. Adult Treatment Panel III guidelines of the National Cholesterol Education Program were used to classify normal/abnormal lipid fractions. Executive functioning was assessed with the Frontal Assessment Battery (FAB). Logistic regression was performed to assess associations between lipids fractions and FAB score. Correlations between lipids fractions and FAB score were explored. Sex-stratified analysis was performed. Three hundred and forty-eight PD patients (148 women; age 66.5 ± 9.5 years; disease duration 3.9 ± 4.9 years) were enrolled. Women presented significantly higher TC, LDL and HDL than men. In the whole sample, any association between lipid profile measures and FAB score was found. Among women, a positive association between hypertriglyceridemia and FAB score under cutoff was found (OR 3.4; 95%CI 1.29-9.03; p value 0.013). A statistically significant negative correlation was found between the FAB score and triglyceride serum levels (r = - 0.226; p value 0.005). Differently, among men, a statistically significant negative association between hypercholesterolemia and FAB score under cutoff (OR 0.4; 95%CI 0.17-0.84; p value 0.018) and between high LDL levels and FAB score under cutoff (OR 0.4; 95%CI 0.18-0.90; p value 0.027) were found. Our data suggest a sex-specific different role of lipids in executive functioning.


Subject(s)
Parkinson Disease , Adult , Aged , Cholesterol, HDL , Cholesterol, LDL , Female , Humans , Lipids , Male , Middle Aged , Parkinson Disease/complications , Triglycerides
12.
Curr Neuropharmacol ; 20(5): 998-1003, 2022.
Article in English | MEDLINE | ID: mdl-34951389

ABSTRACT

BACKGROUND: polytherapy and the anticholinergic activity of several drugs negatively influence cognition in the elderly. However, little is known on the effect on Mild Cognitive Impairment (MCI) in Parkinson's Disease (PD). METHODS: patients with PD belonging to the baseline PACOS cohort with full pharmacological data have been included in this study. MCI diagnosis was made according to the MDS level II criteria. Polytherapy was defined as patients assuming ≥6 drugs. The anticholinergic burden has been calculated using the Anticholinergic Drug Scale (ADS). Molecules have been classified according to the ATC classification. Association with MCI has been assessed with a multivariate logistic regression analysis with MCI as the dependent variable. RESULTS: pharmacological data were available for 238 patients (mean age 64.7±9.7). One hundred (42.0%) were diagnosed with MCI. No association was found in the full multivariate model (correcting for age, sex, disease duration, education, UPDRS-ME, LEDD-DAs) with either polytherapy or the ADS. Concerning drug classes, anti-hypertensive medications were positively associated with PD-MCI (OR 2.02;95%CI 1.04-3.89; p=0.035) while gastroprotective agents were negatively associated (OR 0.51; 95%CI 0.27-0.99; p=0.047). CONCLUSION: the magnitude of polytherapy and anticholinergic drugs burden does not appear to modulate MCI risk in PD, probably due to cautious prescription patterns. The effect of antihypertensive and gastroprotective agents on PD-MCI risk, while needing further confirmations, could be relevant for clinical practice.


Subject(s)
Cognitive Dysfunction , Parkinson Disease , Aged , Cholinergic Antagonists/adverse effects , Cognitive Dysfunction/drug therapy , Humans , Middle Aged , Neuropsychological Tests , Parkinson Disease/complications , Parkinson Disease/drug therapy , Parkinson Disease/psychology
13.
Nutrients ; 13(4)2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33921674

ABSTRACT

BACKGROUND: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people's lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March-May lockdown. METHODS: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. RESULTS: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. CONCLUSIONS: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.


Subject(s)
COVID-19/epidemiology , Migraine Disorders/epidemiology , Physical Distancing , Adult , Communicable Disease Control/methods , Exercise , Feeding Behavior , Headache/epidemiology , Humans , Italy/epidemiology , Life Style , Middle Aged , Quality of Life , Quarantine , SARS-CoV-2 , Sleep , Sleep Wake Disorders/epidemiology , Surveys and Questionnaires
14.
Neurol Sci ; 42(9): 3723-3731, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33447925

ABSTRACT

INTRODUCTION: Mild cognitive impairment (MCI) is common in Parkinson's disease (PD), but the underlying pathological mechanism has not been fully understood. Voxel-based morphometry could be used to evaluate regional atrophy and its relationship with cognitive performances in early PD-MCI. PATIENTS AND METHODS: One hundred and six patients with PD were recruited from a larger cohort of patients, the Parkinson's Disease Cognitive Impairment Study (PaCoS). Subject underwent a T1-3D MRI and a complete clinical and neuropsychological evaluation. Patients were divided into PD with normal cognition (PD-NC) and PD-MCI according to the MDS level II criteria-modified for PD-MCI. A subgroup of early patients with short disease duration (≤ 2 years) was also identified. VBM analysis between PD-NC and PD-MCI and between early PD-NC and PD-MCI was performed using two-sample t tests with whole-brain statistical threshold of p < 0.001 uncorrected in the entire PD group and p < 0.05 FWE inside ROIs, in the early PD. RESULTS: Forty patients were diagnosed with MCI and 66 were PD-NC. PD-MCI patients showed significant gray matter (GM) reduction in several brain regions, including frontal gyrus, precuneus, angular gyrus, temporal lobe, and cerebellum. Early PD-MCI showed reduction in GM density in superior frontal gyrus and cerebellum. Moreover, correlation analysis between neuropsychological performances and GM volume of early PD-MCI patients showed associations between performances of Raven and superior frontal gyrus volume, Stroop time and inferior frontal gyrus volume, accuracy of Barrage and volume of precuneus. CONCLUSION: The detection of frontal and cerebellar atrophy, even at an early stage, could be used as an early marker of PD-related cognitive impairment.


Subject(s)
Cognitive Dysfunction , Parkinson Disease , Brain/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Gray Matter/diagnostic imaging , Humans , Magnetic Resonance Imaging , Neuropsychological Tests , Parkinson Disease/complications , Parkinson Disease/diagnostic imaging
15.
Front Psychiatry ; 11: 590134, 2020.
Article in English | MEDLINE | ID: mdl-33381057

ABSTRACT

Objective: The effects of the COVID-19 lockdown on subjects with prodromal phases of dementia are unknown. The aim of this study was to evaluate the motor, cognitive, and behavioral changes during the COVID-19 lockdown in Italy in patients with Parkinson's disease (PD) with and without mild cognitive impairment (PD-MCI and PD-NC) and in patients with MCI not associated with PD (MCInoPD). Methods: A total of 34 patients with PD-NC, 31 PD-MCI, and 31 MCInoPD and their caregivers were interviewed 10 weeks after the COVID-19 lockdown in Italy, and changes in cognitive, behavioral, and motor symptoms were examined. Modified standardized scales, including the Neuropsychiatric Inventory (NPI) and the Movement Disorder Society, Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Parts I and II, were administered. Multivariate logistic regression was used to evaluate associated covariates by comparing PD-NC vs. PD-MCI and MCInoPD vs. PD-MCI. Results: All groups showed a worsening of cognitive (39.6%), pre-existing (37.5%), and new (26%) behavioral symptoms, and motor symptoms (35.4%) during the COVID-19 lockdown, resulting in an increased caregiver burden in 26% of cases. After multivariate analysis, PD-MCI was significantly and positively associated with the IADL lost during quarantine (OR 3.9, CI 1.61-9.58), when compared to PD-NC. In the analysis of MCInoPD vs. PD-MCI, the latter showed a statistically significant worsening of motor symptoms than MCInoPD (OR 7.4, CI 1.09-45.44). Regarding NPI items, nighttime behaviors statistically differed in MCInoPD vs. PD-MCI (16.1% vs. 48.4%, p = 0.007). MDS-UPDRS parts I and II revealed that PD-MCI showed a significantly higher frequency of cognitive impairment (p = 0.034), fatigue (p = 0.036), and speech (p = 0.013) than PD-NC. On the contrary, PD-MCI showed significantly higher frequencies in several MDS-UPDRS items compared to MCInoPD, particularly regarding pain (p = 0.001), turning in bed (p = 0.006), getting out of bed (p = 0.001), and walking and balance (p = 0.003). Conclusion: The COVID-19 quarantine is associated with the worsening of cognitive, behavioral, and motor symptoms in subjects with PD and MCI, particularly in PD-MCI. There is a need to implement specific strategies to contain the effects of quarantine in patients with PD and cognitive impairment and their caregivers.

16.
Life (Basel) ; 10(11)2020 Oct 30.
Article in English | MEDLINE | ID: mdl-33143156

ABSTRACT

Extremophiles are optimal models in experimentally addressing questions about the effects of cosmic radiation on biological systems. The resistance to high charge energy (HZE) particles, and helium (He) ions and iron (Fe) ions (LET at 2.2 and 200 keV/µm, respectively, until 1000 Gy), of spores from two thermophiles, Bacillushorneckiae SBP3 and Bacilluslicheniformis T14, and two psychrotolerants, Bacillus sp. A34 and A43, was investigated. Spores survived He irradiation better, whereas they were more sensitive to Fe irradiation (until 500 Gy), with spores from thermophiles being more resistant to irradiations than psychrotolerants. The survived spores showed different germination kinetics, depending on the type/dose of irradiation and the germinant used. After exposure to He 1000 Gy, D-glucose increased the lag time of thermophilic spores and induced germination of psychrotolerants, whereas L-alanine and L-valine increased the germination efficiency, except alanine for A43. FTIR spectra showed important modifications to the structural components of spores after Fe irradiation at 250 Gy, which could explain the block in spore germination, whereas minor changes were observed after He radiation that could be related to the increased permeability of the inner membranes and alterations of receptor complex structures. Our results give new insights on HZE resistance of extremophiles that are useful in different contexts, including astrobiology.

17.
Ital J Pediatr ; 46(1): 86, 2020 Jun 22.
Article in English | MEDLINE | ID: mdl-32571386

ABSTRACT

BACKGROUND: Furosemide is approved in full term neonates to treat edema associated with congestive heart failure, cirrhosis and renal diseases. It is often administered off-label in premature neonates, to treat respiratory conditions and at doses greater-than-recommended. We conducted a national survey on behalf of the Neonatal Pharmacotherapy Study Group of the Italian Society of Neonatology (SIN), to investigate its use in Italian neonatal intensive care units (NICUs), in conformity with current guidelines. METHODS: Between December 2016 and June 2017, a 14-item multiple-choice online questionnaire was sent to all NICU directors from the SIN directory. Gestational age, route of administration, posology, indications, referenced guidelines, adverse effects monitoring and the presence of Paediatric Cardiology or Cardiosurgery service on site were assessed. A chi-square test was performed 1) to evaluate differences in the distribution of responses between NICUs administering furosemide at doses higher-than-recommended; 2) to compare the proportion of NICUs administering furosemide at high doses in institutions with versus without a Paediatric Cardiology or Cardiosurgery service. RESULTS: The response rate was 50% (57/114). The intravenous and oral routes were chosen primarily; the intravenous administration in single doses predominated over continuous infusion. Its main therapeutic indications were congestive heart failure/overload (94.7%) and oligo-anuria (87.7%) however furosemide was also frequently used for broncopulmonary dysplasia (50.9%) and respiratory distress syndrome and/or transient tachypnea of the newborn (24.6%). In 28/57 NICUs furosemide was administered at doses higher-than-recommended. In most NICUs the same posology was used in term and preterm neonates. Compared to the total sample, a larger proportion of NICUs administering doses greater-than-recommended referenced current literature for reasons to do so (19.3 and 32.1% respectively). The presence of a Paediatric Cardiology or Cardiosurgery service on site did not correlate with the chosen posology. The majority of NICUs performed acoustic test and renal ultrasound for furosemide exposure greater than 2 weeks. CONCLUSIONS: In Italian NICUs, furosemide is commonly prescribed to term and preterm newborns for label and unlabeled indications. Doses greater-than-recommended are frequently administered. Such use is not necessarily inappropriate. More research is required to assess the efficacy and safety of unlabeled use.


Subject(s)
Critical Care , Furosemide/therapeutic use , Practice Patterns, Physicians' , Sodium Potassium Chloride Symporter Inhibitors/therapeutic use , Guideline Adherence , Humans , Infant, Newborn , Intensive Care Units, Neonatal , Italy , Off-Label Use , Surveys and Questionnaires
18.
Materials (Basel) ; 13(5)2020 Mar 02.
Article in English | MEDLINE | ID: mdl-32121630

ABSTRACT

Experimental findings obtained by FTIR and Raman spectroscopies on montmorillonite-water mixtures at three concentration values are presented. To get some insight into the hydrogen bond network of water within the montmorillonite network, FTIR and Raman spectra have been collected as a function of time and then analyzed following two complementary approaches: An analysis of the intramolecular OH stretching mode in the spectral range of 2700-3900 cm-1 in terms of two Gaussian components, and an analysis of the same OH stretching mode by wavelet cross-correlation. The FTIR and Raman investigations have been carried as a function of time for a montmorillonite-water weight composition (wt%) of 20%-80%, 25%-75%, and 35%-65%, until the dehydrated state where the samples appear as a homogeneous rigid layer of clay. In particular, for both the FTIR and Raman spectra, the decomposition of the OH stretching band into a "closed" and an "open" contribution and the spectral wavelet analysis allow us to extract quantitative information on the time behavior of the system water content. It emerges that, the total water contribution inside the montmorillonite structure decreases as a function of time. However, the relative weight of the ordered water contribution diminishes more rapidly while the relative weight of the disordered water contribution increases, indicating that a residual water content, characterized by a highly structural disorder, rests entrapped in the montmorillonite layer structure for a longer time. From the present study, it can be inferred that the montmorillonite dehydration process promotes the layer self-assembly.

19.
Int J Biol Macromol ; 145: 77-83, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31870877

ABSTRACT

The novel exopolysaccharide (EPS-B3-15) produced by the marine thermotolerant Bacillus licheniformis strain B3-15, constituted by mannose and glucose, has been recently reported as a valuable biopolymer in pharmaceutical applications. To dynamically characterize the thermal behavior of the whole EPS-B3-15 system, the Attenuated Total Reflectance Fourier Transform Infra-Red spectroscopy technique was used over a temperature range from ambient to 78.5 °C. The molecular changes of EPS-B3-15 during the heating process were evaluated by the spectral distance (SD) and wavelet cross-correlation (XWT) analysis. The thermal analysis revealed that the EPS-B3-15 possessed high stability until 78.5 °C. As evaluated by SD and XWT, the molecular structure of EPS-B3-15 at 45 °C was partially modified, due to -OH groups and the -COOH and -OH interactions, conferring a new conformational structure to the biopolymer. The thermal characterization provides novel information about the molecular conformations of the whole EPS-B3-15 system at different temperatures. The thermostable EPS-B3-15 can be successfully employed for biotechnological, nanotechnological and material science applications even at high temperatures.


Subject(s)
Aquatic Organisms/chemistry , Bacillus licheniformis/chemistry , Polysaccharides, Bacterial/chemistry , Biopolymers/chemistry , Glucose/chemistry , Mannose/chemistry , Molecular Structure , Spectroscopy, Fourier Transform Infrared , Thermotolerance
20.
Phys Chem Chem Phys ; 21(22): 11983-11991, 2019 Jun 05.
Article in English | MEDLINE | ID: mdl-31134980

ABSTRACT

The self-assembly process in a water solution of an amphiphilic polydimethylsiloxane-b-polyethyleneoxide (PDMS-PEO) diblock copolymer was investigated by means of small-angle X-ray scattering (SAXS) experiments in the concentration region below (and near) the critical micellar concentration (c.m.c. = 0.007 g cm-3). In the highly diluted region, at the copolymer concentration of c = 0.002 g cm-3, the early stage of the self-assembly process was characterized by the formation of small (primary) micellar units (with a radius of R = 2.7 nm) with core-shell morphology, which coexisted with larger supramolecular aggregates of entangled micelles (with an average radius of R = 9.5 nm). The increase in the copolymer concentration (to c = 0.005 and c = 0.01 g cm-3) caused increase in the sizes of both the small micelles and supra-micellar aggregates. Interestingly, at the concentration of c = 0.005 g cm-3, both the size and micelle aggregation number (Nagg) were found to increase on increasing the temperature in the range of 10 ≤ T ≤ 55 °C. This phenomenon was characterised by the dehydration process of the ethylene oxide (EO) segments, as evidenced by the calculation of excess water in the hydrophilic shell of the micelles. The more compact (less hydrated) structure of the hydrophilic PEO chains, which strongly influenced the spontaneous curvature of the amphiphile hydrophilic region, turned out to be the driving factor that favoured the increase in the micelle aggregation number with the increase in temperature. The obtained results evidence that the self-assembly process of PDMS-PEO copolymer amphiphiles is a gradual process that is already present at the very low concentration region (far below the macroscopically determined c.m.c.); moreover, it is characterised by a multi-stage organization process, where the primary building blocks self-assemble into more complex secondary structures that encompass multiple length scales.

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