Intracellular trafficking and cellular uptake mechanism of PHBV nanoparticles for targeted delivery in epithelial cell lines

Indexación: Web of Science; Scopus; Scielo.Background: Nanotechnology is a science that involves imaging, measurement, modeling and a manipulation of matter at the nanometric scale. One application of this technology is drug delivery systems based on nanoparticles obtained from natural or synthetic sources. An example of these systems is synthetized from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which is a biodegradable, biocompatible and a low production cost polymer. The aim of this work was to investigate the uptake mechanism of PHBV nanoparticles in two different epithelial cell lines (HeLa and SKOV-3). Results: As a first step, we characterized size, shape and surface charge of nanoparticles using dynamic light scattering and transmission electron microscopy. Intracellular incorporation was evaluated through flow cytometry and fluorescence microscopy using intracellular markers. We concluded that cellular uptake mechanism is carried out in a time, concentration and energy dependent way. Our results showed that nanoparticle uptake displays a cell-specific pattern, since we have observed different colocalization in two different cell lines. In HeLa (Cervical cancer cells) this process may occur via classical endocytosis pathway and some internalization via caveolin-dependent was also observed, whereas in SKOV-3 (Ovarian cancer cells) these patterns were not observed. Rearrangement of actin filaments showed differential nanoparticle internalization patterns for HeLa and SKOV-3. Additionally, final fate of nanoparticles was also determined, showing that in both cell lines, nanoparticles ended up in lysosomes but at different times, where they are finally degraded, thereby releasing their contents. Conclusions: Our results, provide novel insight about PHBV nanoparticles internalization suggesting that for develop a proper drug delivery system is critical understand the uptake mechanism.https://jnanobiotechnology.biomedcentral.com/articles/10.1186/s12951-016-0241-

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Abstract:  The Provincial Institute of Alcoholism and Drug Addiction (IPAD) is a monovalent institution that provides treatment to people with problematic substance use. It belongs to the third level of health care involving those cases that cannot be resolved in general hospitals. The present study could contribute to a better understanding of the problem in our environment and the development of future studies and prevention strategies. Objectives: To determine and categorize the prevalence of use of substance according to the type of substance and age group in patients hospitalized in the IPAD in a period of 6 months from September 2019 to March 2020; to describe sociodemographic factors. After signing the informed consent, an interview was conducted based on the Addiction Severity Index (ASI) for sociodemographic factors and a review of medical records to determine the substance for which the patient was being treated. The categorical variables were presented in percentages and were statistically analyzed with the Chi Square test. The results were statistically significant with p less than 0.05. The present work was approved by the CIEIS HNC-FCM. Our sample was of 53 patients. 81.1% were male and 58% manifested incomplete secondary education. Regarding the ages, 49% were between 21-34 years old, 34% between 35-48 years old and 17% ≥49 years old. 51% went to treatment on their own initiative, from a family member or friend, and 40% legally induced. Of the total of patients surveyed, 81% consume alcohol, 75% cocaine and 43% marijuana. According to their medical history, 30% used alcohol, marijuana and cocaine simultaneously; followed by 23% who consumed only alcohol. The patients who consumed only alcohol were around 51 years old, and those who consumed alcohol, cocaine and marijuana were on average 32 years old (p <0.05).  In conclusion, the male sex predominates in the institution; prevailing polydrug use in younger patients and in older patients the use only alcohol. Further studies are suggested in this last group.Resumen:  El Instituto provincial de Alcoholismo y Drogadicción (IPAD) es una institución monovalente que brinda tratamiento a personas con consumo problemático de sustancias. Pertenece al tercer nivel de atención de salud, es decir, asisten aquellos casos que no pueden ser resueltos en centros de salud, dispensarios y hospitales generales. El presente estudio podría contribuir a un mejor conocimiento de la problemática en nuestro medio y así, la elaboración de futuros estudios y estrategias de prevención. Objetivos: Determinar y categorizar la prevalencia del consumo según sustancia y grupo etario en pacientes internados en IPAD en un periodo de 6 meses comprendidos entre septiembre 2019 a marzo 2020; describir los factores sociodemográficos. Posterior a la firma del consentimiento informado, se realizó una entrevista basada en el Índice de severidad de la adicción (ASI) para los factores sociodemográficos  y la revisión de historias clínicas para determinar la sustancia por la que estaba siendo tratado el paciente. Las variables categóricas se presentaron en porcentajes y se analizaron estadísticamente con el test Chi Cuadrado. Los resultados se consideraron significativos con la p menor a 0,05. El presente trabajo fue aprobado por el CIEIS HNC-FCM. Nuestra muestra fue de 53 pacientes. El 81,1% fueron de género masculino y el 58% manifestó secundario incompleto. Respecto a las edades el 49% tenía entre 21-34 años, el 34% entre 35-48 años y el 17% ≥ 49 años. El 51% acudieron al tratamiento por iniciativa suya, de un familiar o amigo, y el 40% de manera legal. Del total de pacientes encuestados, el 81% consume alcohol, 75% consume cocaína y el 43% marihuana. Según la historia clínica, el 30% consumía alcohol, marihuana y cocaína de manera simultánea; seguido del 23% que consumía solo alcohol. Los pacientes que consumían solo alcohol tenían alrededor de los 51 años, y los que consumían alcohol, cocaína y marihuana tenían en promedio 32 años (p <0,05).  En conclusión, predomina el sexo masculino en la institucion;   prevaleciendo el policonsumo en los pacientes más jóvenes y en edades más avanzadas predomina el monopolio etílico. Se sugiere mayores estudios en este último grupo.

Similarity solutions for unsteady shear-stress-driven flow of Newtonian and power-law fluids : slender rivulets and dry patches

Unsteady flow of a thin film of a Newtonian fluid or a non-Newtonian power-law fluid with power-law index N driven by a constant shear stress applied at the free surface, on a plane inclined at an angle α to the horizontal, is considered. Unsteady similarity solutions representing flow of slender rivulets and flow around slender dry patches are obtained. Specifically, solutions are obtained for converging sessile rivulets (0 < α < π/2) and converging dry patches in a pendent film (π/2 < α < π), as well as for diverging pendent rivulets and diverging dry patches in a sessile film. These solutions predict that at any time t, the rivulet and dry patch widen or narrow according to |x|3/2, and the film thickens or thins according to |x|, where x denotes distance down the plane, and that at any station x, the rivulet and dry patch widen or narrow like |t|−1, and the film thickens or thins like |t|−1, independent of N

Functional abilities, respiratory and cardiac function in a large cohort of adults with Duchenne muscular dystrophy treated with glucocorticoids

\ua9 2024 The Authors. European Journal of Neurology published by John Wiley &amp; Sons Ltd on behalf of European Academy of Neurology.Background and purpose: The transition to adult services, and subsequent glucocorticoid management, is critical in adults with Duchenne muscular dystrophy. This study aims (1) to describe treatment, functional abilities, respiratory and cardiac status during transition to adulthood and adult stages; and (2) to explore the association between glucocorticoid treatment after loss of ambulation (LOA) and late-stage clinical outcomes. Methods: This was a retrospective single-centre study on individuals with Duchenne muscular dystrophy (≥16 years old) between 1986 and 2022. Logistic regression, Cox proportional hazards models and survival analyses were conducted utilizing data from clinical records. Results: In all, 112 individuals were included. Mean age was 23.4 \ub1 5.2 years and mean follow-up was 18.5 \ub1 5.5 years. At last assessment, 47.2% were on glucocorticoids; the mean dose of prednisone was 0.38 \ub1 0.13 mg/kg/day and of deflazacort 0.43 \ub1 0.16 mg/kg/day. At age 16 years, motor function limitations included using a manual wheelchair (89.7%), standing (87.9%), transferring from a wheelchair (86.2%) and turning in bed (53.4%); 77.5% had a peak cough flow &lt;270 L/min, 53.3% a forced vital capacity percentage of predicted &lt;50% and 40.3% a left ventricular ejection fraction &lt;50%. Glucocorticoids after LOA reduced the risk and delayed the time to difficulties balancing in the wheelchair, loss of hand to mouth function, forced vital capacity percentage of predicted &lt;30% and forced vital capacity &lt;1 L and were associated with lower frequency of left ventricular ejection fraction &lt;50%, without differences between prednisone and deflazacort. Glucocorticoid dose did not differ by functional, respiratory or cardiac status. Conclusion: Glucocorticoids after LOA preserve late-stage functional abilities, respiratory and cardiac function. It is suggested using functional abilities, respiratory and cardiac status at transition stages for adult services planning

The association of cold weather and all-cause and cause-specific mortality in the island of Ireland between 1984 and 2007

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.This article has been made available through the Brunel Open Access Publishing Fund.Background This study aimed to assess the relationship between cold temperature and daily mortality in the Republic of Ireland (ROI) and Northern Ireland (NI), and to explore any differences in the population responses between the two jurisdictions. Methods A time-stratified case-crossover approach was used to examine this relationship in two adult national populations, between 1984 and 2007. Daily mortality risk was examined in association with exposure to daily maximum temperatures on the same day and up to 6 weeks preceding death, during the winter (December-February) and cold period (October-March), using distributed lag models. Model stratification by age and gender assessed for modification of the cold weather-mortality relationship. Results In the ROI, the impact of cold weather in winter persisted up to 35 days, with a cumulative mortality increase for all-causes of 6.4% (95%CI=4.8%-7.9%) in relation to every 1oC drop in daily maximum temperature, similar increases for cardiovascular disease (CVD) and stroke, and twice as much for respiratory causes. In NI, these associations were less pronounced for CVD causes, and overall extended up to 28 days. Effects of cold weather on mortality increased with age in both jurisdictions, and some suggestive gender differences were observed. Conclusions The study findings indicated strong cold weather-mortality associations in the island of Ireland; these effects were less persistent, and for CVD mortality, smaller in NI than in the ROI. Together with suggestive differences in associations by age and gender between the two Irish jurisdictions, the findings suggest potential contribution of underlying societal differences, and require further exploration. The evidence provided here will hope to contribute to the current efforts to modify fuel policy and reduce winter mortality in Ireland

Computing the common zeros of two bivariate functions via Bézout resultants

The common zeros of two bivariate functions can be computed by finding the common zeros of their polynomial interpolants expressed in a tensor Chebyshev basis. From here we develop a bivariate rootfinding algorithm based on the hidden variable resultant method and Bézout matrices with polynomial entries. Using techniques including domain subdivision, Bézoutian regularization, and local refinement we are able to reliably and accurately compute the simple common zeros of two smooth functions with polynomial interpolants of very high degree (≥ 1000). We analyze the resultant method and its conditioning by noting that the Bézout matrices are matrix polynomials. Two implementations are available: one on the Matlab Central File Exchange and another in the roots command in Chebfun2 that is adapted to suit Chebfun’s methodology

γ-Glutamylcysteine detoxifies reactive oxygen species by acting as glutathione peroxidase-1 cofactor

Reactive oxygen species regulate redox-signaling processes, but in excess they can cause cell damage, hence underlying the aetiology of several neurological diseases. Through its ability to down modulate reactive oxygen species, glutathione is considered an essential thiol-antioxidant derivative, yet under certain circumstances it is dispensable for cell growth and redox control. Here we show, by directing the biosynthesis of γ-glutamylcysteine—the immediate glutathione precursor—to mitochondria, that it efficiently detoxifies hydrogen peroxide and superoxide anion, regardless of cellular glutathione concentrations. Knocking down glutathione peroxidase-1 drastically increases superoxide anion in cells synthesizing mitochondrial γ-glutamylcysteine. In vitro, γ-glutamylcysteine is as efficient as glutathione in disposing of hydrogen peroxide by glutathione peroxidase-1. In primary neurons, endogenously synthesized γ-glutamylcysteine fully prevents apoptotic death in several neurotoxic paradigms and, in an in vivo mouse model of neurodegeneration, γ-glutamylcysteine protects against neuronal loss and motor impairment. Thus, γ-glutamylcysteine takes over the antioxidant and neuroprotective functions of glutathione by acting as glutathione peroxidase-1 cofactor

Relaxation of Adaptive Evolution during the HIV-1 Infection Owing to Reduction of CD4+ T Cell Counts

Background: the first stages of HIV-1 infection are essential to establish the diversity of virus population within host. It has been suggested that adaptation to host cells and antibody evasion are the leading forces driving HIV evolution at the initial stages of AIDS infection. in order to gain more insights on adaptive HIV-1 evolution, the genetic diversity was evaluated during the infection time in individuals contaminated by the same viral source in an epidemic cluster. Multiple sequences of V3 loop region of the HIV-1 were serially sampled from four individuals: comprising a single blood donor, two blood recipients, and another sexually infected by one of the blood recipients. the diversity of the viral population within each host was analyzed independently in distinct time points during HIV-1 infection.Results: Phylogenetic analysis identified multiple HIV-1 variants transmitted through blood transfusion but the establishing of new infections was initiated by a limited number of viruses. Positive selection (d(N)/d(S)>1) was detected in the viruses within each host in all time points. in the intra-host viruses of the blood donor and of one blood recipient, X4 variants appeared respectively in 1993 and 1989. in both patients X4 variants never reached high frequencies during infection time. the recipient, who X4 variants appeared, developed AIDS but kept narrow and constant immune response against HIV-1 during the infection time.Conclusion: Slowing rates of adaptive evolution and increasing diversity in HIV-1 are consequences of the CD4+ T cells depletion. the dynamic of R5 to X4 shift is not associated with the initial amplitude of humoral immune response or intensity of positive selection.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fed Univ Para, Inst Biotechnol, BR-66059 Belem, Para, BrazilUniv São Paulo, Inst Trop Med, São Paulo, SP, BrazilCDC, Ctr Dis Control & Prevent, Branch Lab, Atlanta, GA 30333 USAUniv Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USABlood Syst Res Inst, San Francisco, CA USABlood Syst Inc, San Francisco, CA USAUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilFAPESP: 07/52841-8Web of Scienc