Tribomechanical Properties of PVA/Nomex Composite Hydrogels for Articular Cartilage Repair.

Due to the increasing prevalence of articular cartilage diseases and limitations faced by current therapeutic methodologies, there is an unmet need for new materials to replace damaged cartilage. In this work, poly(vinyl alcohol) (PVA) hydrogels were reinforced with different amounts of Nomex (known for its high mechanical toughness, flexibility, and resilience) and sterilized by gamma irradiation. Samples were studied concerning morphology, chemical structure, thermal behavior, water content, wettability, mechanical properties, and rheological and tribological behavior.

Understanding the impact of nuclear-localized GPCRs on cellular signalling.

G protein-coupled receptors (GPCRs) have historically been associated with signalling events driven from the plasma membrane. More recently, signalling from endosomes has been recognized as a feature of internalizing receptors. However, there was little consideration given to the notion that GPCRs can be targeted to distinct subcellular locations that did not involve an initial trafficking to the cell surface.

The Low Survivability of Transplanted Gonadal Grafts: The Impact of Cryopreservation and Transplantation Conditions on Mitochondrial Function.

Advances in tissue preservation techniques have allowed reproductive medicine and assisted reproductive technologies (ARTs) to flourish in recent years. Because radio- and chemotherapy procedures are often gonadotoxic, irreversible damage can preclude future gamete production and endocrine support. Accordingly, in recent years, the freezing and storage of gonadal tissue fragments prior to the first oncological treatment appointment and autologous transplantation post-recovery have been considered improved solutions for fertility recovery in cancer survivors.

Strategies Used by Nurses to Maintain Person-Family Communication during the COVID-19 Pandemic: A Scoping Review.

: The COVID-19 pandemic made nurse-patient-family communication more difficult, reducing the understanding of the patient's wishes and current care history. COVID-19 challenged healthcare teams to develop strategies to address these changes and provide more integrated care using the technology at their disposal. So, this study aims to map the strategies used by nurses to maintain communication between the person hospitalized with COVID-19 and the family to understand which communication technologies were most used to maintain communication between the person and the family.

Postmortem Ultrastructural Analysis of the Retina from COVID-19 Deceased Patients.

Purpose: COVID-19 (coronavirus disease 2019) is an infectious disease caused by SARS-CoV-2, first reported in 2019 in Wuhan, China. Among the common complications is a pro-inflammatory and hypercoagulative response that compromises the vasculature among various organs.

Methods: In this report, we present the postmortem retinal findings of five patients observed by means of optical microscopy and transmission and scanning electron microscopy techniques.

Recent Advances on 3D-Printed Zirconia-Based Dental Materials: A Review.

Zirconia-based materials are widely used in dentistry due to their biocompatibility and suitable mechanical and tribological behavior. Although commonly processed by subtractive manufacturing (SM), alternative techniques are being explored to reduce material waste, energy consumption and production time. 3D printing has received increasing interest for this purpose.

Mitochondria as biological targets for stem cell and organismal senescence.

Organismal aging is impacted by the deterioration of tissue turnover mechanisms due, in part, to the decline in stem cell function. This decline can be related to mitochondrial dysfunction and underlying energetic defects that, in concert, help drive biological aging. Thus, mitochondria have been described as a potential interventional target to hinder the loss of stem cell robustness, and subsequently, decrease tissue turnover decline and age-associated pathologies.

Choroidal melanoma tumor profile and treatment pattern for newly diagnosed patients at a reference public hospital in Sao Paulo, Brazil.

Background: Choroid, ciliary body, and iris melanomas are often grouped as uveal melanoma, the most common intraocular primary malignancy. The purpose of the current study was to analyze the tumor profile of newly diagnosed cases of choroidal melanoma at a reference center in Sao Paulo, Brazil, and to investigate the frequency of eyes treated by enucleation that could have been treated with brachytherapy if available in the service.

Methods: Medical records of patients referred to our service with initial diagnostic hypothesis of choroidal melanoma from July 2014 to June 2020 were analysed on demographics, diagnosis confirmation, tumor measurement by ultrasonography and established treatment.

Leucine and Arginine Availability Modulate Mouse Embryonic Stem Cell Proliferation and Metabolism.

Amino acids are crucial nutrients involved in several cellular and physiological processes, including fertilization and early embryo development. In particular, Leucine and Arginine have been shown to stimulate implantation, as lack of both in a blastocyst culture system is able to induce a dormant state in embryos. The aim of this work was to evaluate the effects of Leucine and Arginine withdrawal on pluripotent mouse embryonic stem cell status, notably, their growth, self-renewal, as well as glycolytic and oxidative metabolism.

Extracellular vesicles enriched with an endothelial cell pro-survival microRNA affects skin tissue regeneration.

Endothelial cell (EC) activity is essential for tissue regeneration in several (patho)physiological contexts. However, our capacity to deliver biomolecules capable of controlling EC fate is relatively limited. Here, we screened a library of microRNA (miR) mimics and identified 25 miRs capable of enhancing the survival of ECs exposed to ischemia-mimicking conditions.

Differential Oxygen Exposure Modulates Mesenchymal Stem Cell Metabolism and Proliferation through mTOR Signaling.

Mesenchymal stem cells reside under precise hypoxic conditions that are paramount in determining cell fate and behavior (metabolism, proliferation, differentiation, etc.). In this work, we show that different oxygen tensions promote a distinct proliferative response and affect the biosynthetic demand and global metabolic profile of umbilical cord-mesenchymal stem cells (UC-MSCs).

PVA-Based Hydrogels Loaded with Diclofenac for Cartilage Replacement.

Polyvinyl alcohol (PVA) hydrogels have been widely studied for cartilage replacement due to their biocompatibility, chemical stability, and ability to be modified such that they approximate natural tissue behavior. Additionally, they may also be used with advantages as local drug delivery systems. However, their properties are not yet the most adequate for such applications.

Development of polycarbonate urethane-based materials with controlled diclofenac release for cartilage replacement.

Hydrogels are very promising human cartilage replacement materials since they are able to mimic its structure and properties. Besides, they can be used as platforms for drug delivery to reduce inflammatory postsurgical reactions. Polycarbonate urethane (PCU) has been used in orthopedic applications due to its long-term biocompatibility and bio-durability.

Retinal autofluorescence findings after COVID-19.

The main purpose of this study was to investigate the presence of retinal autofluorescence findings in COVID-19 patients. Observational study conducted in São Paulo in 2020. Demographic, medical history, and concomitant events, as well as medications used, hospitalization details, and laboratory test results, were obtained.

Assessing the effect of adenoidectomy on nasal resistance and airflow. A systematic review and meta-analysis.

Objective: Clinical guidelines suggest adenoidectomy when enlarged adenoids are associated with nasal obstruction and other symptoms. Given that nasal obstruction is the leading symptom of adenoid hypertrophy, it should be thoroughly explored. However, there is no consensus regarding what could be the best approach.

What is the relationship between the size of the adenoids and nasal obstruction? A systematic review.

Objective: adenoidectomy is one of the most common surgical procedure in pediatric otolaryngology practice. Clinical guidelines (such as the Spanish or American) suggest adenoidectomy when the enlargement of the adenoids is associated with nasal obstruction. Nasal endoscopy and cephalograms are adequate methods to estimate the size of the adenoids.

Presumed SARS-CoV-2 Viral Particles in the Human Retina of Patients With COVID-19.

Importance: The presence of the SARS-CoV-2 virus in the retina of deceased patients with COVID-19 has been suggested through real-time reverse polymerase chain reaction and immunological methods to detect its main proteins. The eye has shown abnormalities associated with COVID-19 infection, and retinal changes were presumed to be associated with secondary microvascular and immunological changes.

Objective: To demonstrate the presence of presumed SARS-CoV-2 viral particles and its relevant proteins in the eyes of patients with COVID-19.

Relationship between short lingual frenulum and malocclusion. A multicentre study.

Objective: Ankyloglossia is characterized by an abnormally short lingual frenulum, which impairs tongue movement. Ankyloglossia has been related to craniofacial growth disturbances and dental malocclusion. But even though there is a clear biological plausibility for this hypothesis, available evidence is scarce.

Monitoring Mitochondrial Function in Mouse Embryonic Stem Cells (mESCs).

Mouse embryonic stem cells (mESCs) can be grown in culture, recapitulating the different states of pluripotency of their in vivo counterparts, with notably different metabolic profiles. mESCs in a naïve pluripotent state present an ambivalent metabolism, using both glycolysis and oxidative phosphorylation as energy sources. Here, we describe a method to evaluate the oxidative function of naïve mESCs using the Seahorse Extracellular Flux Analyzer coupled to flow cytometry analysis of mitochondrial transmembrane potential using the TMRM fluorescence probe, thus assessing both oxygen consumption and mitochondrial membrane potential.

COVID-19 Retinal Findings in Patients Admitted to Intensive Care Units and Wards.

The main purpose of this study was to investigate ocular clinical findings in patients with confirmed COVID-19 infection, of various levels of disease severity, who required mechanical ventilation and admission to intensive care units or specialized wards. Longitudinal, observational study conducted from March 2020 to June 2020. Color fundus and red-free photography were performed in both eyes following pupillary dilation.

Gestational Diabetes Mellitus and Obesity are Related to Persistent Hyperglycemia in the Postpartum Period.

Objective:  To evaluate the obstetric and sociodemographic characteristics of gestational diabetic women who maintained hyperglycemia in the postpartum period (6-12 weeks postpartum).

Methods:  This is a longitudinal cohort study with women who have had gestational diabetes and/or macrosomic children between March 1, 2016 and March 1, 2017. Between 6 and 12 weeks after birth, women who had gestational diabetes collected fasting glycemia, glucose tolerance test, and glycated hemoglobin results.

Effects of DMSO on the Pluripotency of Cultured Mouse Embryonic Stem Cells (mESCs).

DMSO is a commonly used solvent in biological studies, as it is an amphipathic molecule soluble in both aqueous and organic media. For that reason, it is the vehicle of choice for several water-insoluble substances used in research. At the molecular and cellular level, DMSO is a hydrogen-bound disrupter, an intercellular electrical uncoupler, and a cryoprotectant, among other properties.

A State-of-the-Art Review on the Wear of the Occlusal Surfaces of Natural Teeth and Prosthetic Crowns.

This review focuses on the wear mechanisms of natural and restorative dental materials, presenting a comprehensive description and analysis of the works published in the last two decades on the wear at the interface of occlusal surfaces. Different groups of tribological pairs were considered: tooth-tooth, tooth-restorative material (tooth-ceramic, tooth-resin-based-materials, and tooth-metal), and restorative-restorative materials. The lack of standardization of the wear tests impairs the direct comparison of the obtained results.