A Calorimetric Study on Diflunisal Release from Poly(Lactide-co-Glycolide) Microspheres by Monitoring the Drug Effect on Dipalmitoylphosphatidylcholine Liposomes: Temperature and Drug Loading Influence

Diflunisal release from poly-Lactide-co-Glycolide (50:50, 34,000 MW) microspheres loaded with two different amounts of drug (2.5 +/- 0.5% and 10 +/- 0.5% w/w) was monitored by following the effects exerted by the drug on the thermotropic behavior of dipalmitoylphosphatidylcholine unilamellar vesicles at different temperatures. The effects of the drug released from the microspheres on the thermotropic behavior of lipid aqueous dispersion containing different molar ratios of drug was detected by differential scanning calorimetry and was compared with the effects exerted by the free Diflunisal. Diflunisal affects mainly the temperature (Tm) of the transition characteristic of phospholipid vesicles as model biomembrane, causing a shift toward lower values. This shift was modulated by the drug molar fraction with respect to the lipid concentration in the aqueous dispersion. Afterward, calorimetric measurements were performed on suspensions of blank liposomes added to weighed amounts of unloaded and differently Diflunisal-loaded microspheres as well as free powdered Diflunisal after incubation for increasing times at three different temperatures (25, 37, and 50 degrees C). The Tm shifts of the lipid bilayer, caused by the drug released from polymeric system as well as by the free drug during incubation periods, were compared with that caused by free drug increasing molar fractions dispersed directly on the membrane, employed as a calibration curve to obtain the fraction of drug released. This in vitro study suggests that the kinetic process involved in drug release is influenced by the amount of drug loaded in the microspheres as well as by the temperature acting on drug solubility and membrane disorder. This drug release model, monitored by the calorimetric technique shows that a) the poly-Lactide-co-Glycolide microspheres are a good delivery system able to sustain the drug release; b) the differential scanning calorimetry technique applied on the drug interaction with biomembranes constitutes a good tool to follow the drug release; 3) this model, representing an innovative alternative in vitro model, should be used to determine the different kinetics involved in the drug transfer from a drug delivery system to a membrane as uptake site

Métodos cromatográficos para determinar aminas biogênicas em alimentos de origem animal

Biogenic amines (BAs) are formed as a result of specific free amino acid decarboxylation. Analysis of these metabolites may be of great importance to determine food quality and for monitoring the levels of biogenic amines such as histamine and tyramine related to intoxication episodes in humans. Chromatography is a chemistry separation technique used to characterize biogenic amines in foods. Variations of this technique (liquid, thin layer and gas chromatography) have been widely applied; however, the food matrix complex requires that changes in the methodology of extraction, derivatization and detection must be performed according to each group of foods. High-performance liquid chromatography is the most widely used chromatographic method applied for biogenic amines in foods. However, due to the current importance of biogenic amines in quality control and consumer safety, researchers try to develop new methods for a fast, reliable analysis of foods in the market. This review presents some chromatographic techniques applied to monitoring BAs in different foods of animal origin.Aminas biogenicas sao formadas como resultado da descarboxilacao de aminoacidos livres especificos. A analise desses metabolitos e de grande importancia na determinacao da qualidade e monitoramento de biogenicas como histamina e tiramina relacionadas com episodios de intoxicacao em humanos. A cromatografia e uma tecnica de separacao química usada para caracterizar aminas biogenicas. Variacoes da tecnica (cromatografia liquida, em camada delgada e gasosa) tem sido amplamente usadas, porem a complexidade da matriz alimentar faz com que sejam realizadas mudancas nos processos de extracao, derivatizacao e deteccao em concordancia com cada grupo de alimento. A cromatografia liquida de alta eficiencia (CLAE) e o metodo mais utilizado na determinacao de aminas biogenicas em alimentos. Contudo, devido a importancia das aminas biogenicas no controle da qualidade e a seguranca do consumidor, os pesquisadores tentam desenvolver novos metodos com o intuito de uma analise mais rapida e precisa para o controle de alimentos no mercado. O objetivo da revisao e apresentar algumas tecnicas cromatograficas aplicadas no monitoramento de aminas biogenicas em produtos de origem animal

A national priority: LIS faculty and students as library advocates

Library advocacy is a long-standing tradition at UNCG’s Department of Library and Information Science. The LIS faculty take leadership roles in advocacy and legislation both at state and national levels and make it a point to engage students in their efforts as part their students’ learning experience while earning the MLIS. Over the years, practicum and independent research studies have been offered and student interns have served for years as the backbone of advocacy efforts for the state under the supervision of faculty including overseeing the North Carolina Library Advocacy’s website (nclibraryadvocacy.org) and social media, helping coordinate state and legislative days, and helping schedule visits with members of Congress. ALA’s Committee on Library Advocacy discovered this educational partnership and has identified student advocacy internships in LIS programs as a high priority win-win advocacy activity for 2020-2021. What better way to learn about advocacy in your master’s program then to actually do advocacy as an internship experience? What better way to add young, strong advocates to speak on behalf of libraries then by having them earn credit as part of their degree? Student Perspectives What did you learn in terms of the current state of advocacy for libraries during our internship? Synergistic thought Organizational support is essential. Synergistic thinking among library associations partnered with a more collaborative approach are critically important and often lacking in North Carolina’s advocacy efforts according to former North Carolina Advocacy and Legislation Committee interns. Organizations within the state who operate as independent entities, as opposed to elements in a wider scheme, hinder the growth and success of the whole. Discrepancy in the support that library associations receive is evident. Helping library associations recognize the importance of library advocacy critical as is aligning advocacy goals with the agenda of each organization. Dawn Haney, former committee intern observed “There should be a regular system of “check ins” with leaders of the organizations about convergence points of interest, for example, increasing the funding of libraries within North Carolina. It should be formal and regular - once quarterly at least - to discuss progress toward shared goals.” Haney feels that formal division of labor toward a collaborative goal would be helpful within NC’s advocacy organizations. Convincing library organizations to take on the task of advocating for libraries is essential and should not be taken for granted. Lack of communication and unity. Continuity is a challenge and an area for future development. Creating a sense of overall community and a shared vision would have an enormous impact on the efficacy of library advocacy in North Carolina. What best practices proved to be most beneficial to our efforts? Developing a network Finding library supporters to advocate for you should be the most important goal for any advocacy organization. Librarians consider their work to be essential and can often speak eloquently on this subject. This is a relevant aspect of advocacy but in some instances the importance of libraries is best illustrated by those who have personally benefited from the existence of a library. Advocate to every level of the hierarchy, some of which can only be done at a highly localized level leading to the need for a large network of advocates. When formulating advocacy goals every aspect of the hierarchy that you wish to advocate to should be considered. Decisions are made on every level. A legislator may become more amenable to the idea of increased library funding after a successful library visit but this change of mindset is somewhat irrelevant if, in fact, the city council makes all funding decisions. Former intern Martha McGehee cites the importance of developing a large network of advocates, “involve as many people as possible. Increased participation increases investment as well as awareness. A large team willing to advocate for a library also illustrates support for the library in question. Each advocate brings a unique and valuable perspective to the effort. Our Panel The panel will include Dr. Anthony Chow, Associate Professor at UNCG’s Department of Library and Information Science who is also Co-Chair of Advocacy and Legislation with the North Carolina Library Association (NCLA) and a member of ALA’s Committee on Library Advocacy; Martha McGehee and Ashley Conte, former student advocacy interns; Megan Cusick, ALA’s Assistant Director, State Advocacy; and Justin de la Cruz, Chair, ALA’s Committee on Library Advocacy (COLA). Our panel addresses the conference theme of “Crafting a Resilient Future: Leadership, Education, & Inspiration” by bringing together LIS faculty, students, alumni, and ALA advocacy staff to discuss how we can work closer together and provide a win-win-win scenario where students support statewide and national advocacy efforts, LIS faculty can leverage the current need to advocate for libraries as an experiential learning opportunity, and students learn first hand how to advocate for themselves and libraries

Indomethacin-Dipalmitoylphosphatidylcholine Interaction. A Calorimetric Study of Drug Release from Poly(Lactide-co-glycolide) Microspheres into Multilamellar Vesicles.

A comparative study of indomethacin controlled release from poly(lactide-co-glycolide) (50:50, molecular weight 3000) (PLGA) microspheres loaded with two different amounts of drug (10.9 ± 1%, and 34.1 ± 1% w/w) and pure free indomethacin, considering the effects exerted by the drug on the thermotropic behavior of dipalmitoylphosphatidylcholine multilamellar vesicles, was carried out by differential scanning calorimetry (DSC). The release was monitored by comparing the effect exerted by the free indomethacin on lipid thermotropic behavior with that of the drug released by the microspheres and relating these effects to a lipid aqueous dispersion containing the molar ratio of drug able to cause it. By DSC measurements, the pure free indomethacin was found to be able to have a fluidifying effect on the model membrane, causing a shift toward lower values of the transitional temperature (Tm), characteristic of phospholipid liposomes, without variations in the enthalpic changes (ΔH). This shift was found to be modulated by the drug molar fraction with respect to the lipid concentration in the aqueous dispersion. Successively, calorimetric measurements were performed on suspensions of blank liposomes added to weighed amounts of unloaded and indometha-cin-loaded microspheres as well as free powdered indomethacin, and the Tm shifts of the lipid bilayer caused by the drug released from the polymeric system, as well as by the free drug, were compared with that caused by free drug increasing molar fractions dispersed directly on the membrane, employed as a calibration curve to obtain the fraction of drug released. This drug release model could be employed to determine the different kinetics involved in the drug transfer from the microspheres to a membrane. This in vitro study suggests that the kinetic process involved in drug release is influenced by the amount of drug loaded in the microspheres. This calorimetric study shows that the PLGA microspheres are a good delivery system able to sustain drug release. Moreover, the DSC technique applied to the drug interaction with biomembranes constitutes a good tool for determining the drug release representing an innovative alternative in vitro model

Bioactive compounds from Norway spruce bark: comparison among sustainable extraction techniques for potential food applications

6openInternationalItalian coauthor/editorPicea abies (L.) Karst, (Norway spruce) bark, generally considered as wood industry waste, could potentially be used as a valuable source of antioxidants for food applications. In this study, supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), and ultrasound-assisted extraction (UAE) were carried out in order to recover bioactive compounds from bark of Norway spruce. Obtained results show that PLE with ethanol as solvent was the most effective method for extracting total flavonoid compounds (21.14 ± 1.42 mg quercetin g−1 sample) and consequently exerted the highest antioxidant activity measured by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (257.11 ± 13.31 mg Trolox g−1 sample). On the other hand, UAE extract contained the maximum phenolic concentration (54.97 ± 2.00 mg gallic acid g−1 sample) and the most interesting antioxidant activity measured by the ferric-reducing antioxidant power (580.25 ± 25.18 µmol FeSO4 g−1 sample). Additionally, PLE and UAE have demonstrated great efficiency in the extraction of trans-resveratrol, quantified by HPLC (0.19 and 0.29 mg trans-RSV g−1 sample, respectively)openSpinelli, Sara; Costa, Cristina; Conte, Amalia; La Porta, Nicola; Padalino, Lucia; Del Nobile, Matteo AlessandroSpinelli, S.; Costa, C.; Conte, A.; La Porta, N.; Padalino, L.; Del Nobile, M.A

SARS-CoV-2 concentrations and virus-laden aerosol size distributions in outdoor air in north and south of Italy

The COVID-19 disease spread at different rates in the different countries and in different regions of the same country, as happened in Italy. Transmission by contact or at close range due to large respiratory droplets is widely accepted, however, the role of airborne transmission due to small respiratory droplets emitted by infected individuals (also asymptomatic) is controversial. It was suggested that outdoor airborne transmission could play a role in determining the differences observed in the spread rate. Concentrations of virus-laden aerosol are still poorly known and contrasting results are reported, especially for outdoor environments. Here we investigated outdoor concentrations and size distributions of virus-laden aerosol simultaneously collected during the pandemic, in May 2020, in northern (Veneto) and southern (Apulia) regions of Italy. The two regions exhibited significantly different prevalence of COVID-19. Genetic material of SARS-CoV-2 (RNA) was determined, using both real time RT-PCR and ddPCR, in air samples collected using PM10 samplers and cascade impactors able to separate 12 size ranges from nanoparticles (diameter D < 0.056 µm) up to coarse particles (D > 18 µm). Air samples tested negative for the presence of SARS-CoV-2 at both sites, viral particles concentrations were <0.8 copies m−3 in PM10 and <0.4 copies m−3 in each size range investigated. Outdoor air in residential and urban areas was generally not infectious and safe for the public in both northern and southern Italy, with the possible exclusion of very crowded sites. Therefore, it is likely that outdoor airborne transmission does not explain the difference in the spread of COVID-19 observed in the two Italian regions

Vitamin B supplementation and nutritional intake of methyl donors in patients with chronic kidney disease: A critical review of the impact on epigenetic machinery

Cardiovascular morbidity and mortality are several-fold higher in patients with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) than in the general population. Hyperhomocysteinemia has undoubtedly a central role in such a prominent cardiovascular burden. The levels of homocysteine are regulated by methyl donors (folate, methionine, choline, betaine), and cofactors (vitamin B6, vitamin B12,). Uremia-induced hyperhomocysteinemia has as its main targets DNA methyltransferases, and this leads to an altered epigenetic control of genes regulated through methylation. In renal patients, the epigenetic landscape is strictly correlated with the uremic phenotype and dependent on dietary intake of micronutrients, inflammation, gut microbiome, inflammatory status, oxidative stress, and lifestyle habits. All these factors are key contributors in methylome maintenance and in the modulation of gene transcription through DNA hypo-or hypermethylation in CKD. This is an overview of the epigenetic changes related to DNA methylation in patients with advanced CKD and ESRD. We explored the currently available data on the molecular dysregulations resulting from altered gene expression in uremia. Special attention was paid to the efficacy of B-vitamins supplementation and dietary intake of methyl donors on homocysteine lowering and cardiovascular protection

Noise conversion of Schottky diodes in mm-wave detectors under different nonlinear regimes: modeling and simulation versus measurement

This paper presents and discusses several methods for predicting the low-frequency (LF) noise at the output of a mm-wave detector. These methods are based on the extraction of LF noise source parameters from the single diode under a specific set of bias conditions and the transfer or conversion of these noise sources, under different operating conditions including cyclostationary regime, to the quasi-dc output of a mm-wave detector constructed with the same model of diode. The noise analysis is based on a conversion-matrix type formulation, which relates the carrier noisy sidebands of the input signal with the detector output spectrum through a pair of transfer functions obtained in commercial software. Measurements of detectors in individual and differential setups will be presented and compared with predictions.The authors would like to thank the Spanish Ministry of Science and Innovation (MICINN) for the financial support provided through projects TEC2011-29264-C03-01, CONSOLIDER-INGENIO CSD2008-00068 (TERASENSE), TEC2014-58341-C4-1-R, FEDER co-funding, CONSOLIDER-INGENIO CSD2010-00064 and the University of Cantabria Industrial Doctorate programme 2014, project: “Estudio y Desarrollo de Tecnologías para Sistemas de Telecomunicación a Frecuencias Milimétricas y de Terahercios con Aplicación a Sistemas de Imaging en la Banda 90–100 GHz”

Immunological effects of a single hemodialysis treatment

Immune disorders, involving both innate and adaptive response, are common in patients with end-stage renal disease under chronic hemodialysis. Endogenous and exogenous factors, such as uremic toxins and the extracorporeal treatment itself, alter the immune balance, leading to chronic inflammation and higher risk of cardiovascular events. Several studies have previously described the immune effects of chronic hemodialysis and the possibility to modulate inflammation through more biocompatible dialyzers and innovative techniques. On the other hand, very limited data are available on the possible immunological effects of a single hemodialysis treatment. In spite of the lacking information about the immunological reactivity related to a single session, there is evidence to indicate that mediators of innate and adaptive response, above all complement cascade and T cells, are implicated in immune system modulation during hemodialysis treatment. Expanding our understanding of these modulations represents a necessary basis to develop pro-tolerogenic strategies in specific conditions, like hemodialysis in septic patients or the last session prior to kidney transplant in candidates for receiving a graft