Recent Developments in Layer-by-Layer Assembly for Drug Delivery and Tissue Engineering Applications

Surfaces with biological functionalities are of great interest for biomaterials, tissue engineering, biophysics, and for controlling biological processes. The layer-by-layer (LbL) assembly is a highly versatile methodology introduced 30 years ago, which consists of assembling complementary polyelectrolytes or biomolecules in a stepwise manner to form thin self-assembled films. In view of its simplicity, compatibility with biological molecules, and adaptability to any kind of supporting material carrier, this technology has undergone major developments over the past decades. Specific applications have emerged in different biomedical fields owing to the possibility to load or immobilize biomolecules with preserved bioactivity, to use an extremely broad range of biomolecules and supporting carriers, and to modify the film's mechanical properties via crosslinking. In this review, the focus is on the recent developments regarding LbL films formed as 2D or 3D objects for applications in drug delivery and tissue engineering. Possible applications in the fields of vaccinology, 3D biomimetic tissue models, as well as bone and cardiovascular tissue engineering are highlighted. In addition, the most recent technological developments in the field of film construction, such as high-content liquid handling or machine learning, which are expected to open new perspectives in the future developments of LbL, are presented.

Natural Polymer-Polyphenol Bioadhesive Coacervate with Stable Wet Adhesion, Antibacterial Activity, and On-Demand Detachment

Medical adhesives are emerging as an important clinical tool as adjuvants for sutures and staples in wound closure and healing and in the achievement of hemostasis. However, clinical adhesives combining cytocompatibility, as well as strong and stable adhesion in physiological conditions, are still in demand. Herein, a mussel-inspired strategy is explored to produce adhesive coacervates using tannic acid (TA) and methacrylate pullulan (PUL-MA). TA|PUL-MA coacervates mainly comprise van der Waals forces and hydrophobic interactions. The methacrylic groups in the PUL backbone increase the number of interactions in the adhesives matrix, resulting in enhanced cohesion and adhesion strength (72.7 Jm-2 ), compared to the non-methacrylated coacervate. The adhesive properties are kept in physiologic-mimetic solutions (72.8 Jm-2 ) for 72 h. The photopolymerization of TA|PUL-MA enables the on-demand detachment of the adhesive. The poor cytocompatibility associated with the use of phenolic groups is here circumvented by mixing reactive oxygen species-degrading enzyme in the adhesive coacervate. This addition does not hamper the adhesive character of the materials, nor their anti-microbial or hemostatic properties. This affordable and straightforward methodology, together with the tailorable adhesivity even in wet environments, high cytocompatibility, and anti-bacterial activity, enables foresee TA|PUL-MA as a promising ready-to-use bioadhesive for biomedical applications.

Engaging Early-Career Scientists in Global Policy-Making

Pressing global challenges, such as climate change, the COVID-19 pandemic, or antibiotic resistance, require coordinated international responses guided by evidence-informed decisions. For this purpose, it is critical that scientists engage in providing insights during the decision-making process. However, the mechanisms for the engagement of scientists in policy-making are complex and vary internationally, which often poses significant challenges to their involvement. Herein, we address some of the mechanisms and barriers for scientists to engage in policy-making with a global perspective by early-career scientists. We highlight the importance of scientific academies, societies, universities, and early-career networks as stakeholders and how they can adapt their structures to actively contribute to shaping global policies, with representative examples from chemistry-related disciplines. We showcase the importance of raising awareness, providing resources and training, and leading discussions about connecting emerging scientists with global decision-makers to address societal challenges through policies.

Marine-origin polysaccharides-based free-standing multilayered membranes as sustainable nanoreservoirs for controlled drug delivery

The layer-by-layer (LbL) assembly technology has been widely used to functionalise surfaces and precisely engineer robust multilayered bioarchitectures with tunable structures, compositions, properties, and functions at the nanoscale by resorting to a myriad of building blocks exhibiting complementary interactions. Among them, marine-origin polysaccharides are a sustainable renewable resource for the fabrication of nanostructured biomaterials for biomedical applications owing to their wide bioavailability, biocompatibility, biodegradability, non-cytotoxicity, and non-immunogenic properties. Chitosan (CHT) and alginate (ALG) have been widely employed as LbL ingredients to shape a wide repertoire of size- and shape-tunable electrostatic-driven multilayered assemblies by exploring their opposite charge nature. However, the insolubility of CHT in physiological conditions intrinsically limits the range of bioapplications of the as-developed CHT-based LbL structures. Herein, we report the preparation of free-standing (FS) multilayered membranes made of water-soluble quaternised CHT and ALG biopolymers for controlled release of model drug molecules. The influence of the film structure in the drug release rate is studied by assembling two distinct set-ups of FS membranes, having the model hydrophilic drug fluorescein isothiocyanate-labelled bovine serum albumin (FITC-BSA) either as an intrinsic building block or added as an outer layer after the LbL assembly process. Both FS membranes are characterised for their thickness, morphology, in vitro cytocompatibility, and release profile, with those having FITC-BSA as an intrinsic LbL ingredient denoting a more sustained release rate. This work opens up new avenues for the design and development of a wide array of CHT-based devices for biomedical applications, overcoming the limitations associated with the insolubility of native CHT under physiological conditions.

Self-Supporting Hyaluronic Acid-Functionalized G-Quadruplex-Based Perfusable Multicomponent Hydrogels Embedded in Photo-Cross-Linkable Matrices for Bioapplications

Dynamic G-quadruplex supramolecular hydrogels have aroused great interest in a broad range of bioapplications. However, neither the development of native extracellular matrix (ECM)-derived natural biopolymer-functionalized G-quadruplex hydrogels nor their use to create perfusable self-supporting hydrogels has been explored to date, despite their intrinsic potential as carrier vehicles of therapeutic agents, or even living cells in advanced regenerative therapies, or as platforms to enable the diffusion of nutrients and oxygen to sustain long-term cell survival. Herein, we developed a dynamic co-assembling multicomponent system that integrates guanosine (G), 3-aminophenylboronic acid functionalized hyaluronic acid (HA-PBA), and potassium chloride to bioengineer strong, homogeneous, and transparent HA-functionalized G-quadruplex hydrogels with injectable, thermo-reversible, conductive, and self-healing properties. The supramolecular polymeric hydrogels were developed by hydrogen bonding and π-π stacking interactions between G coupled via dynamic covalent boronate ester bonds to HA-PBA and stabilized by K⁺ ions, as demonstrated by a combination of experiments and molecular dynamics simulations. The intrinsic instability of the self-assembled G-quadruplex structures was used to bioengineer self-supporting perfusable multicomponent hydrogels with interconnected size and shape-tunable hollow microchannels when embedded in 3D methacrylated gelatin supporting matrices. The microchannel-embedded 3D constructs have shown enhanced cell viability when compared to the bulk hydrogels, holding great promise for being use as artificial vessels for enabling the diffusion of nutrients and oxygen essential for cell survival. The proposed approach opens new avenues on the use of ECM-derived natural biopolymer-functionalized dynamic G-quadruplex hydrogels to design next-generation smart systems for being used in tissue regeneration, drug screening, or organ-on-a-chip.

Supramolecular presentation of bioinstructive peptides on soft multilayered nanobiomaterials stimulates neurite outgrowth

Peptide amphiphiles (PAs) have emerged as effective molecular building blocks for creating self-assembling nanobiomaterials for multiple biomedical applications. Herein, we report a straightforward approach to assemble soft bioinstructive platforms to recreate the native neural extracellular matrix (ECM) aiming for neuronal regeneration based on the electrostatic-driven supramolecular presentation of laminin-derived IKVAV-containing self-assembling PA (IKVAV-PA) on biocompatible multilayered nanoassemblies. Spectroscopic and microscopic techniques show that the co-assembly of positively charged low-molecular-weight IKVAV-PA with oppositely charged high-molecular-weight hyaluronic acid (HA) triggers the formation of ordered β-sheet structures denoting a one-dimensional nanofibrous network. The successful functionalization of poly(L-lysine)/HA layer-by-layer nanofilms with an outer positively charged layer of self-assembling IKVAV-PA is demonstrated by the quartz crystal microbalance with dissipation monitoring and the nanofibrous morphological properties revealed by atomic force microscopy. The bioactive ECM-mimetic supramolecular nanofilms promote the enhancement of primary neuronal cells' adhesion, viability, and morphology when compared to the PA without the IKVAV sequence and PA-free biopolymeric multilayered nanofilms, and stimulate neurite outgrowth. The nanofilms hold great promise as bioinstructive platforms for enabling the assembly of customized and robust multicomponent supramolecular biomaterials for neural tissue regeneration.

Fusion Object Detection and Action Recognition to Predict Violent Action

In the context of Shared Autonomous Vehicles, the need to monitor the environment inside the car will be crucial. This article focuses on the application of deep learning algorithms to present a fusion monitoring solution which was three different algorithms: a violent action detection system, which recognizes violent behaviors between passengers, a violent object detection system, and a lost items detection system. Public datasets were used for object detection algorithms (COCO and TAO) to train state-of-the-art algorithms such as YOLOv5. For violent action detection, the MoLa InCar dataset was used to train on state-of-the-art algorithms such as I3D, R(2+1)D, SlowFast, TSN, and TSM. Finally, an embedded automotive solution was used to demonstrate that both methods are running in real-time.

Sensor Fusion Approach for Multiple Human Motion Detection for Indoor Surveillance Use-Case

Multi-human detection and tracking in indoor surveillance is a challenging task due to various factors such as occlusions, illumination changes, and complex human-human and human-object interactions. In this study, we address these challenges by exploring the benefits of a low-level sensor fusion approach that combines grayscale and neuromorphic vision sensor (NVS) data. We first generate a custom dataset using an NVS camera in an indoor environment. We then conduct a comprehensive study by experimenting with different image features and deep learning networks, followed by a multi-input fusion strategy to optimize our experiments with respect to overfitting. Our primary goal is to determine the best input feature types for multi-human motion detection using statistical analysis. We find that there is a significant difference between the input features of optimized backbones, with the best strategy depending on the amount of available data. Specifically, under a low-data regime, event-based frames seem to be the preferred input feature type, while higher data availability benefits the combined use of grayscale and optical flow features. Our results demonstrate the potential of sensor fusion and deep learning techniques for multi-human tracking in indoor surveillance, although it is acknowledged that further studies are needed to confirm our findings.

Chitosan-Based Biomaterials: Insights into Chemistry, Properties, Devices, and Their Biomedical Applications

Chitosan is a marine-origin polysaccharide obtained from the deacetylation of chitin, the main component of crustaceans’ exoskeleton, and the second most abundant in nature. Although this biopolymer has received limited attention for several decades right after its discovery, since the new millennium chitosan has emerged owing to its physicochemical, structural and biological properties, multifunctionalities and applications in several sectors. This review aims at providing an overview of chitosan properties, chemical functionalization, and the innovative biomaterials obtained thereof. Firstly, the chemical functionalization of chitosan backbone in the amino and hydroxyl groups will be addressed. Then, the review will focus on the bottom-up strategies to process a wide array of chitosan-based biomaterials. In particular, the preparation of chitosan-based hydrogels, organic–inorganic hybrids, layer-by-layer assemblies, (bio)inks and their use in the biomedical field will be covered aiming to elucidate and inspire the community to keep on exploring the unique features and properties imparted by chitosan to develop advanced biomedical devices. Given the wide body of literature that has appeared in past years, this review is far from being exhaustive. Selected works in the last 10 years will be considered.

Lipoplex-Functionalized Thin-Film Surface Coating Based on Extracellular Matrix Components as Local Gene Delivery System to Control Osteogenic Stem Cell Differentiation

A gene-activated surface coating is presented as a strategy to design smart biomaterials for bone tissue engineering. The thin-film coating is based on polyelectrolyte multilayers composed of collagen I and chondroitin sulfate, two main biopolymers of the bone extracellular matrix, which are fabricated by layer-by-layer assembly. For further functionalization, DNA/lipid-nanoparticles (lipoplexes) are incorporated into the multilayers. The polyelectrolyte multilayer fabrication and lipoplex deposition are analyzed by surface sensitive analytical methods that demonstrate successful thin-film formation, fibrillar structuring of collagen, and homogenous embedding of lipoplexes. Culture of mesenchymal stem cells on the lipoplex functionalized multilayer results in excellent attachment and growth of them, and also, their ability to take up cargo like fluorescence-labelled DNA from lipoplexes. The functionalization of the multilayer with lipoplexes encapsulating DNA encoding for transient expression of bone morphogenetic protein 2 induces osteogenic differentiation of mesenchymal stem cells, which is shown by mRNA quantification for osteogenic genes and histochemical staining. In summary, the novel gene-functionalized and extracellular matrix mimicking multilayer composed of collagen I, chondroitin sulfate, and lipoplexes, represents a smart surface functionalization that holds great promise for tissue engineering constructs and implant coatings to promote regeneration of bone and other tissues.

Green approaches for extraction, chemical modification and processing of marine polysaccharides for biomedical applications

Over the past few decades, natural-origin polysaccharides have received increasing attention across different fields of application, including biomedicine and biotechnology, because of their specific physicochemical and biological properties that have afforded the fabrication of a plethora of multifunctional devices for healthcare applications. More recently, marine raw materials from fisheries and aquaculture have emerged as a highly sustainable approach to convert marine biomass into added-value polysaccharides for human benefit. Nowadays, significant efforts have been made to combine such circular bio-based approach with cost-effective and environmentally-friendly technologies that enable the isolation of marine-origin polysaccharides up to the final construction of a biomedical device, thus developing an entirely sustainable pipeline. In this regard, the present review intends to provide an up-to-date outlook on the current green extraction methodologies of marine-origin polysaccharides and their molecular engineering toolbox for designing a multitude of biomaterial platforms for healthcare. Furthermore, we discuss how to foster circular bio-based approaches to pursue the further development of added-value biomedical devices, while preserving the marine ecosystem.

AI based monitoring violent action detection data for in-vehicle scenarios

With the evolution of technology associated with mobility and autonomy, Shared Autonomous Vehicles will be a reality. To ensure passenger safety, there is a need to create a monitoring system inside the vehicle capable of recognizing human actions. We introduce two datasets to train human action recognition inside the vehicle, focusing on violence detection. The InCar dataset tackles violent actions for in-car background which give us more realistic data. The InVicon dataset although doesn't have the realistic background as the InCar dataset can provide skeleton (3D body joints) data. This datasets were recorded with RGB, Depth, Thermal, Event-based, and Skeleton data. The resulting dataset contains 6 400 video samples and more than 3 million frames, collected from sixteen distinct subjects. The dataset contains 58 action classes, including violent and neutral (i.e., non-violent) activities.

Death and non-lethal weapons: A case of homicide by penetrating injury without projectile

Herein, we report the death of a man, approximately thirty years old, victim of a short-range shot to the thorax from a PIEXON JPX4, a hand weapon classed category D in France, said to be non-lethal. External examination of the lesion revealed characteristics similar to those of ballistic injuries. The autopsy found an intercostal wound that reached the pulmonary parenchyma and the pulmonary artery, with severe hemothorax. By the end of the autopsy, no projectile had been found in the body, nor any exit orifice. Death was caused by the effects of hemorrhagic shock. The PIEXON JPX4 has four cartridges, projecting a capsaicin gel that is designed to irritate the ENT area (ear nose throat) to incapacitate an assailant. The manufacturer recommends not to use it at distances of less than 1.5 m. Experimental shots were performed on gelatine blocks at point-blank range and at distances of 5, 10, 20, 30, 50, 100 and 150 cm to evaluate the distance necessary for the jet of gel to have a penetrating effect. Shots at 5-30 cm penetrated the structure. None of the other shots were penetrating. The autopsy and experiment data therefore show the penetrating potential of the jet of gel. Herein, we report the first death due to use of the PIEXON JPX4. From a forensic investigation viewpoint, we add a new exception to the "bullet rule". (The odd and even bullet rule states that if the number of gunshot wounds of entrance and exit found in the body is even, the presumption is that no bullet is lodged in the body. If the number of gunshot wounds of entrance and exit is odd, the presumption is that one or more bullets have been lodged in the body.).

AI Based Monitoring of Different Risk Levels in COVID-19 Context

COVID-19 was responsible for devastating social, economic, and political effects all over the world. Although the health authorities imposed restrictions provided relief and assisted with trying to return society to normal life, it is imperative to monitor people's behavior and risk factors to keep virus transmission levels as low as possible. This article focuses on the application of deep learning algorithms to detect the presence of masks on people in public spaces (using RGB cameras), as well as the detection of the caruncle in the human eye area to make an accurate measurement of body temperature (using thermal cameras). For this task, synthetic data generation techniques were used to create hybrid datasets from public ones to train state-of-the-art algorithms, such as YOLOv5 object detector and a keypoint detector based on Resnet-50. For RGB mask detection, YOLOv5 achieved an average precision of 82.4%. For thermal masks, glasses, and caruncle detection, YOLOv5 and keypoint detector achieved an average precision of 96.65% and 78.7%, respectively. Moreover, RGB and thermal datasets were made publicly available.

Antibacterial bioglass in dental implants: a canine clinical study

Background

Peri-implantitis is considered the most challenging biological complication in implantology, as untreated disease can progress and result in implant loss. Therefore, disease prevention is crucial in daily clinical practice. It has been reported that the use of bioactive glass, as an implant coating, can stimulate tissue integration and accelerate tissue regeneration. Besides these properties, it is possible to promote bacterial activity by inserting silver into the bioglass

Methods

Bioglass with composition 45S5 was synthesised by the fusion method, replacing the amount of Na2CO3 by AgNO3 (BG 2% wt). The implants were resealed by the CoBlast® technique. Clinical cases with pathology of the mandible/maxilla were selected and implants dimensioned for the canine bone structure were applied.

Results

Three months after implantation, imaging exams, namely CT scans, showed no signs of early rejection by septic or cytotoxic loss. No decrease or loss of peri-implant bone was observed. In all cases the implants remained without signs of instability, and with sufficient support for the application of the exo-prosthesis or dental crown. The results of histological analysis showed no signs of infection or osteolysis. The zone of peri-implant fibrosis was not observable in the samples, showing a good evolution in implant osteointegration.

Conclusions

The results show promising evidences for the use of this biomaterial as a coating, since aseptic rejection, later on, and that related to the shape and biomaterials used in the implant's design, usually begins during the first 3 months.

Nanomaterials for magnetic hyperthermia

Background

Cancer remains as one of the major causes of mortality worldwide. Recent advances in nanoparticles based therapy mark a new era on cancer treatment. Many groups have investigated biological/physical effects of nanoparticles on tumour cells and how these vary with physical parameters such as particle size, shape, concentration and distribution. Magnetic hyperthermia (MHT) can be an alternative or an add-value therapy with demonstrated effectiveness. MHT uses magnetic nanoparticles, which can be directly applied to the tumour, where, by applying an external ac magnetic field, will promote a localized temperature increment that can be controlled.

Methods

LiFe5O8 nanocrystallites were synthesized by a novel and eco-friendly sol-gel process, using powder coconut water (PCW) has a mediated reaction medium. The dried powders were heat-treated between 400 and 1000 °C, being analysed their structure, morphology and magnetic properties; cytotoxicity and magnetic hyperthermia assays were performed.

Results

The heat-treated LiFe5O8 powder led to crystallite sizes from 50 nm to 200 nm. Increasing the temperature of the heat treatment, secondary phases tend to disappear. The cytotoxicity results revealed a non-cytotoxicity property, for concentrations below 5 mg/mL. The sample HT at 1000 °C, revealed hysteresis and magnetic saturation of 73 emu.g−1 at 300 K and a specific absorption rate(SAR) of about 80 W/g.

Conclusions

It was possible to synthesize LiFe5O8 by a novel, eco-friendly and sustainable route. The nanoparticles have a high heat efficiency, especially the sample heat-treated at 1000 °C, with SAR values similar to Fe3O4, showing potential to be used in the treatment of cancer, by MHT.

The influence of an aquatic exercise program on balance in patients with ankylosing spondylitis

Background

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease that leads to a limitation of mobility, which can cause postural deficits and progressive loss of balance. Aquatic exercise improves this health condition. The objetive is to verify the influence of an aquatic exercise program, on balance and functionality, in individuals with AS.

Methods

Pre-experimental study carried out on 6 individuals with AS. All individuals were assessed at baseline (M0) and 12 weeks after the intervention (M1) using the Bath indices (BASMI, BASFI and BASDAI) and the balance assessment protocol (‘Body Sway’) by the Physiosensing Platform. Data were analyzed using the Statistical Program Statistical Package for the Social Sciences (SPSS), version 26. Were used descriptive statistics and Wilcoxon test to compare M0 and M1. The significance value was 0.05.

Results

We verify improvements in BASMI (P = 0.046), BASFI (P = 0.042) and BASDAI (P = 0.027) scores. Through the analysis of the center of pressure variables, there were no statistically significant differences, between moments, in the protocol. However, when assessing balance, in the anteroposterior mean distance in both the protocol (eyes open) and in the protocol (eyes closed), in the root mean square in both protocols and in mediolateral mean velocity, only in the protocol (eyes open), there was a slight decrease in the median value.

Conclusions

The present study suggests that the specific aquatic exercise program, may influence balance and improve functionality in a population with AS. Therefore, the Bath indices translate improvements in the symptoms and functionalities of these participants.

Awake airway endoscopy in mucopolysaccharidosis: a case report

Mucopolysaccharidosis (MPS) are a group of rare genetic inherited diseases with a progressive course due to the accumulation of glycosaminoglycans resulting in anatomic abnormalities and organ dysfunction, including the respiratory, cardiovascular, skeletal, and neurological systems that can increase the risk of anesthesia complications. Clinical manifestations are variable, multisystemic, and include severe morphological changes. The anesthetic management of these patients is complex, particularly airway management, which can be planned to include a fiberoptic airway investigation prior to surgery. We present two cases of patients with MPS type VI and VII who underwent fiberoptic airway mapping under conscious sedation, with no complications. Since MPS is a rare but challenging disease concerning the airway management, we propose a safe and effective anesthetic technique that could be used for fiberoptic bronchoscopy and allow fiberoptic-assisted tracheal intubation at the time of surgery.

Electroconvulsive therapy as life-saving in an acute catatonic syndrome associated with bipolar disorder: A case report

Introduction

Catatonia is a neuropsychiatric syndrome characterized by an onset of a dysfunction in psychomotor activity and/or muscle tone, which may be associated with changes in consciousness, affect, and thinking. It is characterized by negativism, wax flexibility, catalepsy, mutism echolalia, ecopraxia, or stupor. It was first described in 1874 by Kahlbaum, who characterized it as specific motor disorder associated with different psychiatric disorders. Kraepelin and Bleuler restricted catatonia to a specific subtype of schizophrenia. However, the association between catatonia and other disorders, notably mood disorders, has been reinstated, including Bipolar Disorder. Its etiology is multiple and there are two severe forms: Neuroleptic Malignant Syndrome (NMS) and Malignant Catatonia (MC). These are syndromes that present high mortality, and the health professional should be aware of its etiology, signs, symptoms, evaluation and treatment.

Objectives

The aim of this work is to present a clinical case of MC, who was sustained by literature included on scientific platforms.

Methods

Case report

Results

It is essential to recognize the different clinical presentations of catatonia, taking into account that these are psychiatric alterations in which urgent intervention is justified. In the presented case, the use of antipsychotic medication has worsened the motor function and its suspension, associated with the introduction of lorazepam, resulted in a slight improvement. The electroconvulsive therapy was the last resort, fully succeeded.

Conclusions

The relationship between SMN and Catatonia/MC remains nuclear from a psychopathological and pathophysiological point of view. Nevertheless, there is general agreement that catatonia represents a very significant risk factor for NMS.

Disclosure

No significant relationships.

Attention deficit hyperactivity disorder in adulthood and the heritability of this condition

Introduction

Attention Deficit Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder characterized by inattention and/or hyperactivity-impulsivity resulting from the interaction of genetic and environmental risk factors. Family studies shows that persistent ADHD is very familial.

Objectives

We aim to review the literature on this condition and its heritability and describe the implications that a possible misdiagnosis can have during life.

Methods

Bibliography review was performed using the databases PubMed and Cochrane, using the following keywords: “ADHD”; “Adults”; “Heretability”; “Family” and “Rater effect”.

Results

Childhood ADHD persists into adolescence and adulthood substantially, identified in some studies, as going up to 78%. The prevalence of ADHD in children and adults is between 2.5% and 5% worldwide. Family studies have shown that children of adults with ADHD are at higher risk of having ADHD. Some large-scale twin studies of adult ADHD, used self-report assessments of ADHD symptoms and estimated the heritability of this condition to be between 30 to 40%, which differs from other studies that analyse parents and teachers responses and estimates heritability to be between 60 and 90%.

Conclusions

Since there is a direct influence of the evaluators in estimating the extent of ADHD heritability, future studies need to clarify and describe in detail all the related characteristics of the raters. Although ADHD is widely studied, there is still a lot to learn about its etiology. The diagnosis of ADHD is clinical and complex and must be considered both in childhood and adolescence and in adulthood, with special emphasis on the family antecedents.

Disclosure

No significant relationships.

Clozapine in severe psychotic disorders: Balancing safety with efficacy

Introduction

Clozapine is a member of the dibenazepine class of antipsychotic drugs and has been designated an atypical antipsychotic drug. Clinical studies have shown that clozapine is effective in ameliorating the core symptoms, as well as the negative symptoms, in severe psychotic disorders and is therapeutically effective in treating about 30% of schizophrenic patients who are resistant to standard antipsychotic drugs.

Objectives

The goal is to review pharmacology, efficacy, and clinical use of clozapine, such as its side effects, and the benefit-to-risk ratio of this antipsychotic drug.

Methods

Non-systematic literature review based on scientific databases such as PubMed, using key words such as “clozapine”, “efficacy”, “side effects” and “resistant schizophrenia”.

Results

Clozapine was developed as the first atypical antipsychotic with activity for both the negative and positive symptoms of schizophrenia. The primary indications for clozapine are treatment-resistant psychotic disorder, defined as persistent moderate to severe delusions or hallucinations despite two or more clinical trials with other antipsychotic drugs, and patients who are at high risk for suicide. Concerns over a number of safety considerations are responsible for much of the underutilization of clozapine, such as agranulocytosis, metabolic side effects and myocarditis. These side effects can be detected, prevented, minimized and treated, but there will be a very small number of fatalities.

Conclusions

Awareness of the benefits and risks of clozapine is essential for increasing the use of this lifesaving agent.

Disclosure

No significant relationships.

Lithium in severe affective disorders: Balancing safety with efficacy

Introduction

Lithium has been one of the oldest substances used in psychiatric treatments and remains the first-line treatment for prevention of manic and depressive episodes of bipolar disorder (BD), but it has also a wide spectrum of side-effects.

Objectives

The goal is to review efficacy, and clinical use of lithium, such as its side effects, and its benefit-to-risk ratio.

Methods

Non-systematic literature review based on scientific databases such as PubMed.

Results

The first modern use of lithium was for the treatment of mania. Lithium has also proven useful in major depression, particularly for augmentation of antidepressants, for aggressive behavior and it has a specific antisuicide effect. Lithium’s prophylactic and antisuicidal effects are most unique. However, the use of lithium became problematic due to the serious toxicity since lithium also a narrow therapeutic index, with therapeutic levels between 0.6 and 1.5 mEq/L.

Conclusions

Awareness of the benefits and risks of lithium is essential for the use of this lifesaving agent. Lithium levels must be carefully monitored and lithium dosage adjusted as necessary.

Disclosure

No significant relationships.

Supramolecular dendrimer-containing layer-by-layer nanoassemblies for bioapplications: current status and future prospects

This review provides a comprehensive and critical overview of the supramolecular dendrimer-containing multifunctional layer-by-layer nanoassemblies driven by a multitude of intermolecular interactions for biological and biomedical applications.

In vitro biological response of human osteoblasts in 3D chitosan sponges with controlled degree of deacetylation and molecular weight

We have studied the effect of chitosan sponges, produced from chitosan batches with distinct degree of deacetylation (DDA) and molecular weight (Mw), on the adhesion, growth and differentiation of primary human osteoblasts with an aim to offer a suitable tool for guided bone regeneration. All the chitosan sponges revealed similar microstructure, irrespective of the DDA (58, 73, 82, 88, and 91 %) and Mw (749, 547, 263, 215, and 170 kDa, respectively). Cell spreading was higher on sponges having a higher DDA. Higher DDA induced a more pronounced increase in alkaline phosphatase activity, osteopontin (OPN), vascular endothelial growth factor-A (VEGF), interleukin-6 (IL-6), and reduction in monocyte chemoattractant protein-1 (MCP-1), sclerostin (SOST) and dickkopf related protein-1 as compared to lower DDA. Lower DDA induced the increased secretion of osteoprotegerin and SOST as compared to higher DDA. The combination of higher DDA and Mw induced an increased secretion of VEGF and IL-6, however reduced the secretion of OPN as compared to chitosan with similar DDA but with lower Mw. In summary, the variations in cellular responses to the different chitosan sponges indicate a potential for individual tailoring of desired responses in guided bone regeneration.

A Diverse View of Science to Catalyse Change

Valuing diversity leads to scientific excellence, the progress of science and most importantly, it is simply the right thing to do. We can value diversity not only in words, but also in actions.

Enzymatically degradable, starch-based layer-by-layer films: application to cytocompatible single-cell nanoencapsulation

The build-up and degradation of cytocompatible nanofilms in a controlled fashion have great potential in biomedical and nanomedicinal fields, including single-cell nanoencapsulation (SCNE). Herein, we report the fabrication of biodegradable films of cationic starch (c-ST) and anionic alginate (ALG) by electrostatically driven layer-by-layer (LbL) assembly technology and its application to the SCNE. The [c-ST/ALG] multilayer nanofilms, assembled either on individual Saccharomyces cerevisiae or on the 2D flat gold surface, degrade on demand, in a cytocompatible fashion, via treatment with α-amylase. Their degradation profiles are investigated, while systematically changing the α-amylase concentration, by several surface characterization techniques, including quartz crystal microbalance with dissipation monitoring (QCM-D) and ellipsometry. DNA incorporation in the LbL nanofilms and its controlled release, upon exposure of the nanofilms to an aqueous α-amylase solution, are demonstrated. The highly cytocompatible nature of the film-forming and -degrading conditions is assessed in the c-ST/ALG-shell formation and degradation of S. cerevisiae. We envisage that the cytocompatible, enzymatic degradation of c-ST-based nanofilms paves the way for developing advanced biomedical devices with programmed dissolution in vivo.

Advanced Bottom-Up Engineering of Living Architectures

Bottom-up tissue engineering is a promising approach for designing modular biomimetic structures that aim to recapitulate the intricate hierarchy and biofunctionality of native human tissues. In recent years, this field has seen exciting progress driven by an increasing knowledge of biological systems and their rational deconstruction into key core components. Relevant advances in the bottom-up assembly of unitary living blocks toward the creation of higher order bioarchitectures based on multicellular-rich structures or multicomponent cell-biomaterial synergies are described. An up-to-date critical overview of long-term existing and rapidly emerging technologies for integrative bottom-up tissue engineering is provided, including discussion of their practical challenges and required advances. It is envisioned that a combination of cell-biomaterial constructs with bioadaptable features and biospecific 3D designs will contribute to the development of more robust and functional humanized tissues for therapies and disease models, as well as tools for fundamental biological studies.

A diverse view of science to catalyse change

Valuing diversity leads to scientific excellence, the progress of science and, most importantly, it is simply the right thing to do. We must value diversity not only in words, but also in actions. This article is co-published in the following journals: Nature Chemistry (<a target="_blank" rel="nofollow" href="https://doi.org/10.1038/s41557-020-0529-x">https://doi.org/10.1038/s41557-020-0529-x</a>), Chemical Science (<a target="_blank" rel="nofollow" href="https://doi.org/10.1039/D0SC90150D">https://doi.org/10.1039/D0SC90150D</a>), Journal of the American Chemical Society (<a target="_blank" rel="nofollow" href="https://doi.org/10.1021/jacs.0c07877">https://doi.org/10.1021/jacs.0c07877</a>), Angewandte Chemie International Edition (<a target="_blank" rel="nofollow" href="https://doi.org/%2010.1002/anie.202009834">https://doi.org/ 10.1002/anie.202009834</a>), Canadian Journal of Chemistry (<a target="_blank" rel="nofollow" href="https://doi.org/10.1139/cjc-2020-0323">https://doi.org/10.1139/cjc-2020-0323</a>), and Croatica Chemica Acta (<a target="_blank" rel="nofollow" href="https://doi.org/10.5562/diversity2020">https://doi.org/10.5562/diversity2020</a>).

A diverse view of science to catalyse change

Valuing diversity leads to scientific excellence, the progress of science and, most importantly, it is simply the right thing to do. We must value diversity not only in words, but also in actions.

Preparation of Well-Dispersed Chitosan/Alginate Hollow Multilayered Microcapsules for Enhanced Cellular Internalization

Hollow multilayered capsules have shown massive potential for being used in the biomedical and biotechnology fields, in applications such as cellular internalization, intracellular trafficking, drug delivery, or tissue engineering. In particular, hollow microcapsules, developed by resorting to porous calcium carbonate sacrificial templates, natural-origin building blocks and the prominent Layer-by-Layer (LbL) technology, have attracted increasing attention owing to their key features. However, these microcapsules revealed a great tendency to aggregate, which represents a major hurdle when aiming for cellular internalization and intracellular therapeutics delivery. Herein, we report the preparation of well-dispersed polysaccharide-based hollow multilayered microcapsules by combining the LbL technique with an optimized purification process. Cationic chitosan (CHT) and anionic alginate (ALG) were chosen as the marine origin polysaccharides due to their biocompatibility and structural similarity to the extracellular matrices of living tissues. Moreover, the inexpensive and highly versatile LbL technology was used to fabricate core-shell microparticles and hollow multilayered microcapsules, with precise control over their composition and physicochemical properties, by repeating the alternate deposition of both materials. The microcapsules' synthesis procedure was optimized to extensively reduce their natural aggregation tendency, as shown by the morphological analysis monitored by advanced microscopy techniques. The well-dispersed microcapsules showed an enhanced uptake by fibroblasts, opening new perspectives for cellular internalization.

Portuguese recommendations for the prevention, diagnosis and management of primary osteoporosis - 2018 update

BACKGROUND

Advances in osteoporosis (OP)case definition, treatment options, optimal therapy duration and pharmacoeconomic evidence in the national context motivated the Portuguese Society of Rheumatology (SPR) to update the Portuguese recommendations for the diagnosis and management of osteoporosis published in 2007.

METHODS

SPR bone diseases' working group organized meetings involving 55 participants (rheumatologists, rheumatology fellows and one OP specialist nurse) to debate and develop the document. First, the working group selected 11 pertinent clinical questions for the diagnosis and management of osteoporosis in standard clinical practice. Then, each question was investigated through literature review and draft recommendations were built through consensus. When insufficient evidence was available, recommendations were based on experts' opinion and on good clinical practice. At two national meetings, the recommendations were discussed and updated. A draft of the recommendations full text was submitted to critical review among the working group and suggestions were incorporated. A final version was circulated among all Portuguese rheumatologists before publication and the level of agreement was anonymously assessed using an online survey.

RESULTS

The 2018 SPR recommendations provide comprehensive guidance on osteoporosis prevention, diagnosis, fracture risk assessment, pharmacological treatment initiation, therapy options and duration of treatment, based on the best available evidence. They attained desirable agreement among Portuguese rheumatologists. As more evidence becomes available, periodic revisions will be performed. Target audience and patient population: The target audience for these guidelines includes all clinicians. The target patient population includes adult Portuguese people. Intended use: These recommendations provide general guidance for typical cases. They may not be appropriate in all situations - clinicians are encouraged to consider this information together with updated evidence and their best clinical judgment in individual cases.

Nanostructured interfacial self-assembled peptide-polymer membranes for enhanced mineralization and cell adhesion

Soft interfacial materials, such as self-assembled polymer membranes, are gaining increasing interest as biomaterials since they can provide selective barriers and/or controlled affinity interactions important to regulate cellular processes. Herein, we report the design and fabrication of multiscale structured membranes integrating selective molecular functionalities for potential applications in bone regeneration. The membranes were obtained by interfacial self-assembly of miscible aqueous solutions of hyaluronan and multi-domain peptides (MDPs) incorporating distinct biochemical motifs, including mineralizing (EE), integrin-binding (RGDS) and osteogenic (YGFGG) peptide sequences. Circular dichroism and Fourier transform infrared spectroscopy analyses of the MDPs revealed a predominant β-sheet conformation, while transmission electron microscopy (TEM) showed the formation of fibre-like nanostructures with different lengths. Scanning electron microscopy (SEM) of the membranes showed an anisotropic structure and surfaces with different nanotopographies, reflecting the morphological differences observed under TEM. All the membranes were able to promote the deposition of a calcium-phosphate mineral on their surface when incubated in a mineralizing solution. The ability of the MDPs, coated on coverslips or presented within the membranes, to support cell adhesion was investigated using primary adult periosteum-derived cells (PDCs) under serum-free conditions. Cells on the membranes lacking RGDS remained round, while in the presence of RGDS they appear to be more elongated and anchored to the membrane. These observations were confirmed by SEM analysis that showed cells attached to the membrane and exhibiting an extended morphology with close interactions with the membrane surface. We anticipate that these molecularly designed interfacial membranes can both provide relevant biochemical signals and structural biomimetic components for stem cell growth and differentiation and ultimately promote bone regeneration.

Effect of Comedication With Conventional Synthetic Disease-Modifying Antirheumatic Drugs on Retention of Tumor Necrosis Factor Inhibitors in Patients With Spondyloarthritis: A Prospective Cohort Study

OBJECTIVE

To evaluate whether use of comedication with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) influences the retention of tumor necrosis factor inhibitors (TNFi) in patients with spondyloarthritis (SpA).

METHODS

Patients with SpA from the Rheumatic Diseases Portuguese Register who started treatment with their first TNFi between 2001 and 2014 were included in this study. Cox regression analysis was used to estimate the effect of comedication with csDMARDs on TNFi retention in 2 types of models: a model in which baseline (time-fixed) variables were included, and a second model incorporating time-varying variables, including sociodemographic features, measures of disease activity, measures of physical function, and cotreatment with other drugs (nonsteroidal antiinflammatory drugs and oral steroids). To control for possible confounding by indication, the effect of csDMARD comedication on TNFi retention was also tested after adjustment for the treatment propensity score.

RESULTS

In total, 954 patients were included in the study, of whom 289 (30.3%) discontinued treatment with their first TNFi after a median follow-up time of 2.5 years (range 0.08-13 years). Inefficacy was the most common reason for TNFi discontinuation (55.7% of patients). In the multivariable analyses, comedication with csDMARDs had no measurable effect on TNFi retention, neither in the baseline model (hazard ratio [HR] 0.83, 95% confidence interval [95% CI] 0.59-1.16) nor during follow-up in the model adjusted for time-varying covariates (HR 1.07, 95% CI 0.68-1.68). The effect of csDMARD comedication remained nonsignificant after propensity score adjustment.

CONCLUSION

Comedication with csDMARDs does not prolong TNFi retention in patients with SpA in clinical practice, suggesting that there is no benefit conferred by the concomitant use of these drugs.

Depression across DSM and ICD editions: Psychiatric nosology's ‘Black Dog’

Introduction

The diagnosis of depressive disorders has suffered important modifications throughout DSM and ICD editions. The history of those modifications is an important subject to fully understand the current diagnostic criteria and classification, with milestones often set not by scientific or theoretical data but rather by political decision and conflicting interests.

Objective

The authors propose a review of how the concept of major depression has evolved along the several DSM and ICD editions.

Methods

The results were obtained searching literature included on the platforms PubMed, Google Scholar, PsycINFO and Psychology and Behavioral Sciences Collection.

Results

The current diagnostic entity lacks validity and utility and that is an obstacle to both scientific research and clinical practice.

Conclusion

The authors also discuss alternative models which may contribute to a paradigm shift more suitable to clinical reality and to provide a useful framework for all levels of research.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Regret Anticipation Failures Scale (RAFS): Validation of the Portuguese version

Introduction

Failures in regret anticipation undermine regret avoidance, increasing regret frequency and ultimately the risk of regret-related problems. The Regret Anticipation Failures Scale (RAFS; Schmidt and Linden, 2011) was developed to evaluate interindividual differences in regret anticipation.

Objective

To investigate the psychometric properties of the RAFS Portuguese version.

Methods

A community sample composed of 108 university students and 79 employees (78.1% females; mean age = 33.16 ± 13.175; range: 17–62) answered the Portuguese preliminary version of the RAFS. To study the temporal stability, 31 participants (83.9% females; mean age = 26.54 ± 18.761) answered the RAFS again after approximately 6 weeks.

Results

The RAFS Cronbach alpha was “very good” (a = 0.81). All the items presented significant correlations with the total (excluding the item; > 0.20); only item 2 (Even when I’m stressed, I can foresee the regrets that certain behaviors could evoke in me) had the effect of lowering the internal consistency if deleted. The test-retest correlation coefficient was high, positive and significant (0.61; P < 0.001); there was not significant difference between test and re-test scores [14.26 ± 5.170 vs. 13.06 ± 4.761, t (30) = 1.532, P = 0.136]. Following Kaiser and Cattel Scree Plot criteria, only one factor was extracted, meaning that the scale is unidimensional.

Conclusions

The Portuguese version of RAFS has good reliability and construct validity. It could be very useful both in clinical and research contexts, namely in an ongoing project on the relationship between regret, personality and psychological distress.

Disclosure of interest

The authors have not supplied their declaration of competing interest.