Electroactive poly(vinylidene fluoride-trifluoroethylene)/graphene composites for cardiac tissue engineering applications

Electroactive materials are increasingly being used in strategies to regenerate cardiac tissue. These materials, particularly those with electrical conductivity, are used to actively recreate the electromechanical nature of the cardiac tissue. In the present work, we describe a novel combination of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)), a highly electroactive polymer, with graphene (G), exhibiting high electrical conductivity. G/P(VDF-TrFE) films have been characterized in terms of topographical, physico-chemical, mechanical, electrical, and thermal properties, and studied the response of cardiomyocytes adhering to them. The results indicate that the crystallinity and the wettability of the composites remain almost unaffected after G incorporation. In turn, surface roughness, Young modulus, and electric properties are higher in G/P(VDF-TrFE). Finally, the composites are highly biocompatible and able to support cardiomyocyte adhesion and proliferation, particularly surface treated ones, demonstrating the suitability of these materials for cardiac tissue engineering applications.

Enantioselectivity in ecotoxicity of pharmaceuticals, illicit drugs, and industrial persistent pollutants in aquatic and terrestrial environments: A review

At present, there is a serious concern about the alarming number of recalcitrant contaminants that can negatively affect biodiversity threatening the ecological status of marine, estuarine, freshwater, and terrestrial ecosystems (e.g., agricultural soils and forests). Contaminants of emerging concern (CEC) such as pharmaceuticals (PHAR), illicit drugs (ID), industrial persistent pollutants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) and chiral ionic solvents are globally spread and potentially toxic to non-target organisms. More than half of these contaminants are chiral and have been measured at different enantiomeric proportions in diverse ecosystems. Enantiomers can exhibit different toxicodynamics and toxicokinetics, and thus, can cause different toxic effects. Therefore, the enantiomeric distribution in occurrence cannot be neglected as the toxicity and other adverse biological effects are expected to be enantioselective. Hence, this review aims to reinforce the recognition of the stereochemistry in environmental risk assessment (ERA) of chiral CEC and gather up-to-date information about the current knowledge regarding the enantioselectivity in ecotoxicity of PHAR, ID, persistent pollutants (PCBs and PBDEs) and chiral ionic solvents present in freshwater and agricultural soil ecosystems. We performed an online literature search to obtain state-of-the-art research about enantioselective studies available for assessing the impact of these classes of CEC. Ecotoxicity assays have been carried out using organisms belonging to different trophic levels such as microorganisms, plants, invertebrates, and vertebrates, and considering ecologically relevant aquatic and terrestrial species or models organisms recommended by regulatory entities. A battery of ecotoxicity assays was also reported encompassing standard acute toxicity to sub-chronic and chronic assays and different endpoints as biomarkers of toxicity (e.g., biochemical, morphological alterations, reproduction, behavior, etc.). Nevertheless, we call attention to the lack of knowledge about the potential enantioselective toxicity of many PHAR, ID, and several classes of industrial compounds. Additionally, several questions regarding key species, selection of most appropriate toxicological assays and ERA of chiral CEC are addressed and critically discussed.

Beyond activity patterns: The complex process of activity management among individuals with chronic musculoskeletal pain after an orthopaedic trauma

CONTEXT

Individuals must change the way they perform activities in response to chronic pain. In the literature, three activity patterns are commonly described: avoidance, pacing, and persistence. Many studies have explored these activity patterns. However, little research has delved into the factors that lead people to adopt a particular activity behaviour. This study aimed to explore the relationship that people with chronic musculoskeletal pain have with activity and highlight the factors underlying their practices.

METHODS

The qualitative study was conducted by researchers in the social sciences, physiotherapy, psychology, and rehabilitation medicine. Observations of vocational workshops and semi-structured interviews were conducted with 33 persons undergoing rehabilitation for chronic musculoskeletal pain after an accident.

RESULTS

Patients' declarations and actions show that any one patient will alternate between activity patterns: the same person may adopt a strategy of avoidance, pacing or persistence depending on the context, the importance of the activity, personal objectives, and representations of self, pain, and activity. The decision to engage in a particular behaviour is based on a process of self-negotiation weighted by the circumstances, the nature of the activity, the importance attached to it, and the individual's perceived ability.

CONCLUSION

Our study emphasized the complexity of physical, social, and contextual factors that intervene in the relationship toward activity. Rather than favouring pacing, the therapist's role in rehabilitation might be to reinforce the reflexive process and the patient's adaptability in approaching the activity, to foster the capacity to find flexible solutions.

SIGNIFICANCE

Patients choose an activity pattern (avoidance, pacing, persistence) according to the challenges they face in their daily lives. Context, representations of self and activity, as well as goals sought influence these choices. Some patients report having learned to adapt their activity management strategies. Therefore, therapeutic approaches in the rehabilitation context could focus on these adaptive capacities to offer patients optimal pain and activity management and develop their ability to use different strategies according to the circumstance.

Allergic emergencies in the prehospital setting: a 5 year retrospective study

Summary

Background. Patients with severe allergic conditions often request support from the prehospital emergency services given the rapid, unexpected and potentially life-threatening nature of the reactions, such as anaphylaxis. Studies regarding prehospital incidents for allergic conditions are scarce. This study aimed to characterize prehospitalar medical requesting assistance due to suspected hypersensitivity reactions (HSR). Methods. Retrospective study of allergic-related requesting assistances between 2017-2022 of a Portuguese emergency dispatch centre - Emergency and Resuscitation Medical Vehicle (VMER), in Coimbra University Hospital. Demographic and clinical variables were analysed, including clinical manifestations, anaphylaxis severity grading, therapeutic interventions, and post-incident allergic work-up. Regarding anaphylactic events, three diagnosis timings were compared: on-site, hospital emergency department and Investigator-diagnosis based on data reviewed. Results. Out of 12689 VMER requesting assistances, 210 (1.7%) were classified as suspected HSR reactions. After on-site medical evaluation, 127 (60.5%) cases maintained the HSR classification (median age 53 years; 56% males) and the main diagnoses included HSR to Hymenoptera venom (29.9%), food allergy (29.1%), and pharmaceutical drugs (25.5%). Anaphylaxis was assumed on-site in 44 (34.7%) cases, in the hospital emergency department in 53 cases (41.7%) and by investigators in 76 (59.8%) cases. Regarding management, epinephrine was administered on-site in 50 cases (39.4%). Conclusions. The main reason for prehospital requesting assistance was HSR to Hymenoptera venom. A high proportion of incidents met the criteria for anaphylaxis and despite the inherent difficulties of the prehospital setting, many of the on-site diagnoses agreed with the criteria. Regarding management, epinephrine was underused in this setting. Referral to specialized consultation is crucial for the management of prehospital incidents.

Improving the Performance of Paper-Based Dipole Antennas by Electromagnetic Flux Concentration

One of the essential issues in modern advanced materials science is to design and manufacture flexible devices, in particular in the framework of the Internet of Things (IoT), to improve integration into applications. An antenna is an essential component of wireless communication modules and, in addition to flexibility, compact dimensions, printability, low cost, and environmentally friendlier production strategies, also represent relevant functional challenges. Concerning the antenna's performance, the optimization of the reflection coefficient and maximum range remain the key goals. In this context, this work reports on screen-printed paper@Ag-based antennas and optimizes their functional properties, with improvements in the reflection coefficient (S₁₁) from -8 to -56 dB and maximum transmission range from 208 to 256 m, with the introduction of a PVA-Fe₃O₄@Ag magnetoactive layer into the antenna's structure. The incorporated magnetic nanostructures allow the optimization of the functional features of antennas with possible applications ranging from broadband arrays to portable wireless devices. In parallel, the use of printing technologies and sustainable materials represents a step toward more sustainable electronics.

DESIGN AND STUDY OF DIFFERENT PVDF STRUCTURES

Introduction

Tissue engineering (TE) is a promising technology that can develop structures very similar to native tissues to improve or replace their biological functions. Polyvinylidene fluoride (PVDF) is a new thermoplastic polymer widely used in biomedical applications. Each structure of PVDF has different mechanical and biological characteristics depending on its morphology and the methodology employed.

Methods

Doctor blade, salt leaching, and electrospinning methodologies were used to design different PVDF structures, including films, porous membranes, and electrospun membranes, respectively. Furthermore, electrospun PVDF membranes were developed according to the direction of the strands, obtaining membranes that were oriented as well as with random orientation. All these morphologies were subjected to mechanical, cytotoxicity and degradation studies.

Results

All PVDF morphologies underwent a minimum modification of 16% with respect to their original size. The porous membranes were the most fragile structures, and the electrospun membranes were the most resistant. According to ISO standard 10993–5, a material is considered to be biocompatible when the values are higher than 70%, and all PVDF morphologies had cell viability values above the 70% threshold. Finally, results showed that there was no degradability, regardless of the method or structure designed.

Conclusions

PVDF is a material with good mechanical characteristics, given that structures designed with electrospinning can withstand more stress. In addition, this material is non-degradable and biocompatible, broadening the range of biomedical and TE applications.

DESIGN AND STUDY OF DIFFERENT SILK FIBROIN STRUCTURES

Introduction

Tissue engineering (TE) has the capacity to design structures very similar to native tissues in order to restore, maintain or improve their biological functions. Silk fibroin (SF) is a natural protein that has been used in a wide variety of TE applications. Each SF structure has different mechanical and biological characteristics depending on the morphology and methodology employed.

Methods

Bombyx mori silkworm cocoons were extracted and processed to obtain SF. Subsequently, films, porous membranes, and electrospun membranes were designed using doctor blade, salt leaching, and electrospinning methodologies, respectively. Furthermore, electrospun SF membranes were developed according to the direction of the strands, obtaining membranes that were oriented as well as with random orientation. All these morphologies were subjected to mechanical, cytotoxicity and degradation studies.

Results

The most fragile SF structures were the films and the porous membranes, which underwent a maximum modification of approximately 5% with respect to their original size. However, electrospun membranes underwent a change in size of more than 20%. All SF morphologies had biocompatibility values close to 100%. Finally, there was a degradability between 3–5% at 4 weeks in all structures.

Conclusions

SF has very good mechanical characteristics when designed by electrospinning techniques. Although SF is biocompatible, there is a degradation of the material, which may affect the mechanical properties of the designed structure.

Surface charge and dynamic mechanoelectrical stimuli improves adhesion, proliferation and differentiation of neuron-like cells

Neuronal diseases and trauma are among the current major health-care problems. Patients frequently develop an irreversible state of neuronal disfunction that lacks treatment, strongly reducing life quality and expectancy. Novel strategies are thus necessary and tissue engineering research is struggling to provide alternatives to current treatments, making use of biomaterials capable to provide cell supports and active stimuli to develop permissive environments for neural regeneration. As neuronal cells are naturally found in electrical microenvironments, the electrically active materials can pave the way for new and effective neuroregenerative therapies. In this work the influence of piezoelectric poly(vinylidene fluoride) with different surface charges and dynamic mechanoelectrical stimuli on neuron-like cells adhesion, proliferation and differentiation was addressed. It is successfully demonstrated that both surface charge and electrically active dynamic microenvironments can be suitable to improve neuron-like cells adhesion, proliferation, and differentiation. These findings provide new knowledge to develop effective approaches for preclinical applications.

Unintended intrapleural insertion of an epidural catheter in thoracic surgery: regional analgesia game over, or is there another way out?

In thoracic surgery, optimized pain control is crucial to prevent dysfunction in cardiorespiratory mechanics. Epidural anesthesia (EA) and paravertebral block (PVB) are the most popular techniques for analgesia. Unintended intrapleural insertion of an epidural catheter is a rare complication. Our report presents a case of a patient submitted to pulmonary tumor resection by video-assisted thoracoscopic surgery (VATS). There was difficulty in epidural insertion related to patient's obesity, but after general anesthesia induction, no additional intravenous analgesia was needed after epidural injection. Surgery required conversion to thoracotomy, with intrapleural identification of epidural catheter. At the end of surgery, surgeons reoriented catheter to paravertebral space, with leak absence confirmation after local anesthetic injection through the catheter. In postoperative period, pain control was efficient, with no complications. It was a successful case that shows that when we find unexpected complications, we can look for alternative solutions to give our patient the best treatment.

Prevalence and predictors of acquired long QT syndrome in the ER department

Introduction

Long QT syndrome (LQTS) is a rare heterogeneous syndrome that may be congenital or acquired, the latter being more common. Its real-world prevalence remains to be determined. We aimed to determine the prevalence of this syndrome in patients admitted to the emergency room (ER) and characterize the subset of patients with severely prolonged QT.

Methods

A retrospective analysis of ECG of all consecutively admitted patients in the ER of a tertiary hospital between the 28th of January and the 17th of March 2020 was made. All patients with Bazzett corrected QT interval greater than 470ms in men and 480ms in women were included. Repeated ECGs or with bad electrocardiographic quality, congenital LQTS, atrial fibrillation and pacemaker rhythm were excluded. Clinical data with a special focus on QT prolonging drugs and clinical factors were recorded. Statistical comparison was made between the groups with and without QT interval greater than 500ms.

Results

A total of 6280 ECGs of 5056 patients were analysed. After evaluation, 390 ECGs from 387 different patients were considered. Prevalence of LQTS at admission was 7.95%. Patients were more commonly men (53.1%) with an average age of 73.6±14.7 years old and mean QTc interval of 502.14±32.2ms. Only 20% of the patients were symptomatic, with the most common form of presentation being syncope (50%). No ventricular arrhythmias were recorded.

Regarding patients with a QT interval greater than 500ms, these were more frequently female (59.9% vs 37.2%, p<0.001), were more frequently on QT prolonging drugs (77.8% vs 67.3%; p=0.002). Presence of clinical risk factors was not a risk factor per se (p=0.811) but a greater number of risk factors was linked to more severely prolonged QT (p=0.040). The main contributing factor was intake of antibiotics (odds ratio (OR) 3.497; CI 95% 1.074–11.321; p=0.038) followed by female gender (OR 2.518; CI 95% 1.668–3.800; p<0.001) and use of antipsychotics (OR 1.960; CI 95% 1.159–3.316; p=0.012).

Conclusions

Acquired LQTS is particularly prevalent in the ER setting. The complex interaction of clinical factors and drug iatrogenesis and the unpredictability of its manifestations render its management and recognition difficult but essential. Female patients on antibiotics and antipsychotics are at particularly high risk. Efforts must be made in order to avoid, detect and treat acquired LQTS as early as possible.

Funding Acknowledgement

Type of funding sources: None.

Ionic liquid-based electroactive materials: a novel approach for cardiac tissue engineering strategies

Cardiac tissue regeneration strategies are increasingly taking advantage of electroactive scaffolds to actively recreate the tissue microenvironment. In this context, this work reports on advanced materials based on two different ionic liquids (ILs), 2-hydroxyethyl-trimethylammonium dihydrogen phosphate ([Ch][DHP]) and choline bis(trifluoromethylsulfonyl)imide ([Ch][TFSI]), combined with poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) for the development of ionic electroactive IL/polymer hybrid materials for cardiac tissue engineering (TE). The morphological, physico-chemical, thermal and electrical properties of the hybrid materials, as well as their potential use as scaffolds for cardiac TE applications, were evaluated. Besides inducing changes in surface topography, roughness and wettability of the composites, the incorporation of [Ch][DHP] and [Ch][TFSI] leads to the increase in surface (σ_surface) and volume (σ_volume) electrical conductivities. Furthermore, washing the hybrid samples with phosphate-buffered saline solution strongly decreases the σ_surface, whereas σ_surface and σ_volume of the composites remain almost unaltered after exposure to ultraviolet sterilization treatment. Additionally, it is verified that the incorporation of IL influences the P(VDF-TrFE) microstructure and crystallization process, acting as a defect during its crystallization. Cytotoxicity assays revealed that hybrid films based on [Ch][DHP] alone are not cytotoxic. These films also support H9c2 myoblast cell adhesion and proliferation, demonstrating their suitability for cardiac TE strategies based on electroactive microenvironments.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Electroactive functional microenvironments from bioactive polymers: A new strategy to address cancer

The present work reports on a new approach based on electroactive microenvironments to mitigate skeletal muscle cancer. For that, piezoelectric films based on poly(vinylidene fluoride) have been applied to evaluate the influence of mechano- and/or electrical stimuli on rhabdomyosarcoma (RMS) proliferation. Human embryonal rhabdomyosarcoma (RD) cells were cultured on PVDF pristine films with different surface charge (non-poled, poled+ and poled-) and magnetic composites (10% and 20% Fe₃O₄, and 20% CFO filler content) to allow magneto-mechanical and magnetoelectrical stimulation films. Electrospun PVDF pristine (oriented and randomly) and magnetic (10% Fe₃O₄) fiber mats were also evaluated to take into consideration the morphology effect on cell response. It was found that the mechanical stimuli enhance RMS proliferation whereas the mechano-electrical decreases it. It was also verified that the RD cells proliferate better on randomly oriented fibers, whereas myoblast cells do it better in oriented ones. The obtained results confirm that electroactive microenvironments can be used to develop novel and effective approaches to deal with RMS cancer, that can be extrapolated to others cancer types.

Greener Solvent-Based Processing of Magnetoelectric Nanocomposites

Polymer-based magnetoelectric (ME) nanocomposites are an enabling material technology for a wide range of applications in the area of digitalization strategies. Due to its highest piezoelectric response among polymers, poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) is the piezoelectric matrix most used in polymer-based ME materials with over 80% of the total reports, with the resulting composites typically processed from solutions with N,N-dimethylformamide (DMF), a toxic solvent. Nevertheless, environmentally friendlier approaches and sustainable technologies are increasingly being required. This work demonstrates that P(VDF-TrFE)/Co₂Fe₂O₄ nanocomposites can be successfully prepared from solution using three different environmentally friendlier solvents: dimethyl sulfoxide (DMSO), N,N'-dimethylpropyleneurea (DMPU), and triethyl phosphate (TEP) with different dipole moments. It is shown that the prepared composite films, with a maximum ME voltage coefficient of 35 mV cm^-1 Oe^-1 and a maximum sensitivity of 2.2 mV T^-1, are suitable for applications, highlighting the path for a new generation of more sustainable ME sensors.

Bio-based composite granules with simultaneous biocontrol and phosphorus fertilization roles: outcomes from a lab-scale in-vitro assessment

The use of phosphate rocks as low-solubility phosphorus fertilizers has been promoted to reduce the environmental impacts of agriculture, but adequate nutrient uptake by plants depends on solubilization of the rock, driven by soil microorganisms. Here, investigation was made of the microbial solubilization of low-solubility phosphate rocks, together with simultaneous bioprotective action involving the biocontrol of microorganisms. The aim was to enhance function and value by delivering two effects using a single bio-based product, in accordance with the concept of a "bioreactor-in-a-granule" system. A composite structure was developed, based on a starch matrix, comprising a combination of Trichoderma asperelloides, as a biocontrol agent, and Aspergillus niger, as an acidulant. A significant increase of up to 150% in P solubilization was achieved, indicating the positive effect of the microorganism-composite interaction. In vitro assays showed that the ability of T. asperelloides to inhibit Fusarium oxysporum mycelial growth was maintained in the presence of A. niger. Moreover, the estimated cost of the composite granule (0.35 US$/kg of product on a dry basis) revealed competitive. The results indicated that the association of T. asperelloides and A. niger is an effective way to increase nutrient availability and to inhibit plant pathogens, opening up possibilities for the design of multifunctional bio-based fertilizer composites. This article is protected by copyright. All rights reserved.

Dengue infection in kidney transplant recipients: clinical course and its impact on renal function

Introduction:

Kidney transplant recipients (KTR) are at increased risk for dengue virus (DENV) infection. The aim of this study was to outline the clinical presentation and laboratory profile of DENV infection in KTR and its impact on renal function.

Methods:

This was a retrospective study of KTR diagnosed with DENV infection. Adult patients who visited Santa Casa de Belo Horizonte Nephrology Center between April and September 2019 were included. Patients who did not sign the Informed Consent were excluded. Data were collected from the database and medical records. The study was approved by the local Institutional Ethics Committee and the Informed Consent was obtained.

Results:

Nineteen KTR were evaluated. The main signs and symptoms were myalgia, headache/retro-orbital pain, fever, and gastrointestinal symptoms. Two patients had acute cholecystitis without calculus, three experienced pleural and/or pericardial effusion, and one developed acute myocarditis. All patients were under immunosuppression with prednisone, tacrolimus, and mycophenolate, and most were not receiving induction therapy. Temporary suspension/reduction of immunosuppression was required in 58% of patients and leukopenia was the most common reason. Thrombocytopenia was common and 58% of patients developed acute kidney injury. All patients recovered renal function.

Conclusions:

DENV infection in KTR patients seems to follow a similar course as in the general population. Although there was no control group, we suspect that immunosuppression, preexisting kidney disease or type of donor was not a determining factor in most patients. Transient renal dysfunction was common but reversible. No patient experienced death or graft loss.

Key elements in hypersensitivity reactions to chemotherapy: experience with rapid drug desensitization in gynaecological cancer in a tertiary hospital

Summary

Rapid drug desensitization (RDD) is a procedure performed when no alternative drug is considered equally effective. The aim of our study is to describe the experience with RDD to cytostatics in patients being treated for gynaecological cancer in a tertiary hospital, over a period of 5 years. In this paper, we review 22 cases and 107 episodes of RDD; 86.3% of patients had advanced disease and the mortality rate at the time of data collection was 50.0%. RDD was performed on 81.8% patients for platinum, 13.6% for taxanes, and 4.5% for anthracyclines. The reintroduction of antineoplastic drugs in all patients with a previous history of immediate hypersensitivity reaction demonstrated the safety and efficacy of this procedure. There was serious complication (anaphylaxis) in only one case.

Psychiatric disorders during acute hospital treatment of COVID-19 - a case series

Introduction

Coronavirus disease (COVID-19) has been associated with the development mental and behavioural symptoms and psychiatric disorders. This association is stronger in severe cases of the disease and in those needing inpatient treatment, particularly in intensive care units (ICU).

Objectives

To determine the incidence of psychiatric disorders in a Portuguese hospital-based sample of patients with COVID-19. To describe relevant demographic and clinical data.

Methods

We reviewed all COVID-19 inpatients assessed by liaison psychiatry at our hospital between April and September 2020. Patients admitted due to a psychiatric disorder were excluded from the analysis. We reviewed medical records and retrieved relevant clinical data. ICD-10 was used to classify diagnoses.

Results

We identified 36 cases with a mean age of 62.64 years-old (SD 19.23). The most common disorder was delirium, which occurred in 41.7% of our sample (15 patients), followed by adjustment disorder (22.2%, n=8), and depressive episode (16.7%, n=8). Most patients had no personal (61.1%, n=22) nor family (75%, n=27) history of a psychiatric disorder. Mean length of admission was 36.89 days (SD 28.91). Seventeen cases (47.22%) had at least one risk factor for severe COVID-19 disease and 14 (38.89%) were admitted at some point to the ICU.

Conclusions

In our sample, delirium was the main cause for mental or behavioural symptoms in COVID-19 patients. However, we observed a wide array of presentations in our center. A larger sample would allow to better characterize this often-overlooked symptoms and identify risk factors to psychiatric syndromes.

Disclosure

No significant relationships.

Portuguese adaptation of the S3-non-invasive ventilation (S3-NIV) questionnaire for home mechanically ventilated patients

Short, valid and easy to use tools are needed to monitor non-invasive ventilation in clinical practice and for organization of home mechanical ventilation services. The aim of this study was to develop a professional translation and cultural adaptation of the Portuguese S³ non-invasive ventilation questionnaire. 234 stable patients (128 male patients, 53.8%) with a mean age of 69.3 years under long-term home non-invasive ventilation were recruited from a single-center outpatient clinic. The most frequent diagnostic groups were obesity hypoventilation syndrome, chronic obstructive pulmonary disease and restrictive chest wall disorders. The Portuguese version of the questionnaire was obtained using translation back-translation process with two professional translators. Internal consistency for the total score was good (Cronbach's α coefficient of 0.76) as well as for the "respiratory symptoms" and the "sleep and side effects" domains (Cronbach's α coefficient=0.68 and Cronbach's α coefficient=0.72, respectively). An exploratory factor analysis was performed leading to an explained variance of 54.6%, and resulted in 3 components. The Portuguese version of the S3-NIV questionnaire is a simple and valid tool for the routine clinical assessment of patients receiving home NIV.

As Águas do Rio Caí como Guias: Encontro com Marcos Ambientais do Desenvolvimento Petroquímico Brasileiro

Resumo: Apresentando estudo de dupla autoria, situamos nosso trabalho de campo de pesquisa interdisciplinar sobre a história de um projeto de desenvolvimento emblemático do Brasil, o III Polo Petroquímico, localizado em Triunfo, no Rio Grande do Sul. Trata-se de um dos esforços de compreensão dos embates ocorridos nas décadas de 1970 e 1980: em contexto de ditadura civil-militar, articulações sociais em vários municípios do complexo lagunar Guaíba-Laguna dos Patos resultaram na proteção dos mananciais utilizados para o abastecimento da região metropolitana de Porto Alegre. Em percurso imagético resultante de trabalho empírico, nossa narrativa ressalta, a partir do rio Caí, o manancial em cujas margens situa-se o empreendimento industrial, suas principais referências geográficas e históricas em relação ao aglomerado urbano. Como resultado, sublinhamos a necessidade da conservação e disponibilização pública dos importantes acervos documentais existentes, política fundamental para a continuidade e melhoria do funcionamento das estruturas de proteção ambiental constituídas nesse complexo industrial e em seus similares.Palavras-chave: Narrativa visual. Relato de campo. História ambiental.  GUIDED BY THE RIVER CAÌ WATERS: MEETING THE ENVIRONMENTAL LANDMARKS OF THE BRAZILIAN PETROCHEMICAL DEVELOPMENT   Abstract: Featuring dual authorship, we set forth our interdisciplinary field research on the history of an emblematic development project in Brazil, the III Petrochemical Polo, located in Triunfo, in Rio Grande do Sul. It is one of the efforts made to understand of the clashes that occurred in the 1970s and 1980s: in the context of the civil-military dictatorship, social articulations in several municipalities bordering the Guaíba-Laguna dos Patos lagoon complex resulted in the protection of the sources used to supply the metropolitan region of Porto Alegre. In an imagery path enabled by empirical acquisitions, our narrative highlights, beginning with the River Caí, the source on whose margins is located the industrial complex, its main geographical and historical references in relation to the urban complex. Consequently, we emphasize the need for the conservation and public availability of the important existing documentary collections, a fundamental policy for ensuring the continuity and improved functioning of the environmental protection structures constituted in this industrial complex and other similar complexes.Key-words: Visual narrative. Field report. Environmental history

Rhodococcus equi infection as inaugural manifestation of idiopathic CD4+ lymphopenia: A rare entity and a therapeutic challenge

We report a case of disseminated infection by Rhodococcus equi as the inaugural manifestation of idiopathic T-CD4⁺ lymphopenia. We aim to demonstrate our diagnostic and therapeutic approach and focus on the major dilemmas arising from the lack of scientific evidence regarding best clinical practice of this infection in humans.

A kinetic model of T cell autoreactivity in autoimmune diseases

We construct a mathematical model of kinetic type in order to describe the immune system interactions in the context of autoimmune disease. The interacting populations are self-antigen presenting cells, self-reactive T cells and the set of immunosuppressive cells consisting of regulatory T cells and Natural Killer cells. The main aim of our work is to develop a qualitative analysis of the model equations and investigate the existence of biologically realistic solutions. Having this goal in mind we describe the interactions between cells during an autoimmune reaction based on biological considerations that are given in the literature and we show that the corresponding system of integro-differential equations has finite positive solutions. The asymptotic behaviour of the solution of the system is also studied. We complement our mathematical analysis with numerical simulations that study the sensitivity of the model to parameters related to proliferation of immunosuppressive cells, destruction of self-antigen presenting cells and self-reactive T cells and tolerance of SRTCs to self-antigens.

Evaluation of hybrid neutralization/biosorption process for zinc ions removal from automotive battery effluent by dolomite and fish scales

This work focused in the evaluation of Oreochromis niloticus fish scales (FS) as biosorbent material in the removal of Zn from a synthetic effluent based on automotive battery industry effluent and, further, a hybrid neutralization/biosorption process, aiming at a high-quality treated effluent, by a cooperative use of dolomite and FS. For this, a physicochemical and morphological characterization (i.e. SEM-EDX, FTIR, XRD, and TXRF) was performed, which helped to clarify a great heterogeneity of active sites (phosphate, carbonate, amide, and hydroxyl) on the biosorbent; also the inorganic constituents (apatites) leaching from the FS was identified. Biosorption results pointed out to a pH-dependent process due to changes in the functional group's anionic character (i.e. electrostatic interactions), where an initial pH = 3 favored the Zn uptake. Kinetic and equilibrium studies confirmed the heterogeneous surface and cooperative sorption, wherein experimental data were described by Generalized Elovich kinetic model and the favorable isotherm profile by Langmuir-Freundlich isotherm ( qmax  = 15.38 mg g^-1 and 1/n>1 ). Speciation diagram of Zn species along with the leached species demonstrated that, for the studied pH range, the biosorption was the most likely phenomena rather than precipitation. Finally, the hybrid neutralization/biosorption process showed great potential since both the Zn concentration levels and the pH reached the legislation standards (C_Zn = 4 mg L^-1; pH = 5). Hence, based on the characterization and biosorption results, a comprehensive evaluation of the involved mechanisms in such complex system helped to verify the prospective of FS biosorbent for the Zn treatment from solution, in both individual and hybrid processes.

Distribution and environmental assessment of trace elements contamination of water, sediments and flora from Douro River estuary, Portugal

The present study evaluated the content and distribution of several trace elements (Li, Be, Al, V, Cr, Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, Sb, Ba, Tl, Pb, and U) in the Douro River estuary. For that, three matrices were collected (water, sediments and native local flora) to assess the extent of contamination by these elements in this estuarine ecosystem. Results showed their occurrence in estuarine water and sediments, but significant differences were recorded on the concentration levels and pattern of distribution among both matrices and sampling points. Generally, the levels of trace elements were higher in the sediments than in the respective estuarine water. Nonetheless, no correlation among trace elements was determined between water and sediments, except for Cd. Al was the trace element found at highest concentration at both sediments and water followed by Zn. Pollution indices such as geo-accumulation (I_geo), enrichment factor (EF) and contamination factor (CF) were determined to understand the levels and sources of trace elements pollution. I_geo showed strong contamination by anthropogenic activities for Li, Al, V, Cr, Ni, Cu, Zn, Ba and Pb at all sampling points while EF and CF demonstrated severe enrichment and contamination by Se, Sb and Pb. Levels of trace elements were compared to acceptable values for aquatic organisms and Sediment Quality Guidelines. The concentration of some trace elements, namely Al, Pb and Cu, were higher than those considered acceptable, with potential negative impact on local living organisms. Nevertheless, permissible values for all trace elements are still not available, demonstrating that further studies are needed in order to have a complete assessment of environmental risk. Furthermore, the occurrence and possible accumulation of trace elements by local plant species and macroalgae were investigated as well as their potential use as bioindicators of local pollution and for phytoremediation purposes.

Electroactive biomaterial surface engineering effects on muscle cells differentiation

Even though skeletal muscle cells can naturally regenerate as a response to insignificant tissue damages, more severe injuries can cause irreversible loss of muscle cells mass and/or function. Until now, cell therapies are not a good approach to treat those injuries. Biomaterials such as poly(vinylidene fluoride), PVDF, can improve muscle regeneration by presenting physical cues to muscle cells that mimic the natural regeneration environment. In this way, the ferroelectric and piezoelectric properties of PVDF offer new opportunities for skeletal muscle tissue engineering once the piezoelectricity is an electromechanical effect that can be used to provide electrical signals to the cells, upon mechanical solicitations, similar to the ones found in several body tissues. Thus, previous to dynamic experiments, it is important to determine how the surface properties of the material, both in terms of the poling state (positive or negative net surface charge) and of the morphology (films or fibers) influence myoblast differentiation. It was observed that PVDF promotes myogenic differentiation of C2C12 cells as evidenced by quantitative analysis of myotube fusion, maturation index, length, diameter and number. Charged surfaces improve the fusion of muscle cells into differentiated myotubes, as demonstrated by fusion and maturation index values higher than the control samples. Finally, the use of random and oriented β-PVDF electrospun fibers scaffolds has revealed differences in cell morphology. Contrary to the randomly oriented fibers, oriented PVDF electrospun fibers have promoted the alignment of the cells. It is thus demonstrated that the use of this electroactive polymer represents a suitable approach for the development of electroactive microenvironments for effective muscle tissue engineering.

Assessment of Douro and Ave River (Portugal) lower basin water quality focusing on physicochemical and trace element spatiotemporal changes

Water quality of Douro and Ave lower basin was evaluated regarding physicochemical parameters (pH, conductivity, dissolved oxygen and temperature), nutrient compounds (nitrates, nitrites, ammonium and orthophosphates), chlorophyll a and occurrence of trace elements (Li, Be, Al, Ti, V, Cr, Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, Sb, Ba, Tl, Pb, Th and U). To study spatiotemporal variations and possible anthropogenic sources, estuarine samples were collected at nine sampling sites in Douro and five in Ave distributed along the estuaries at four sampling campaigns (spring, summer, fall and winter). According to the water quality standards for aquatic life and recreation, Douro and Ave river water quality was found out of safe limits regarding several parameters. Nitrate levels were systematically high (> 50 mg L^-1 in a significant number of samples) and mean levels of trace elements were higher than the established values of Canadian Environmental Quality Guidelines for aquatic life protection for Al, Cu, Se, Ag, Cd and Pb in Douro and Ave, and also Zn in Ave. Significant spatial differences were found in Ave river estuary for trace elements with a clear trend for higher values from upstream to downstream found. Seasonal differences were also observed particularly in Douro river estuary with higher levels in spring for most elements.

Human Mesenchymal Stem Cells Growth and Osteogenic Differentiation on Piezoelectric Poly(vinylidene fluoride) Microsphere Substrates

The aim of this work was to determine the influence of the biomaterial environment on human mesenchymal stem cell (hMSC) fate when cultured in supports with varying topography. Poly(vinylidene fluoride) (PVDF) culture supports were prepared with structures ranging between 2D and 3D, based on PVDF films on which PVDF microspheres were deposited with varying surface density. Maintenance of multipotentiality when cultured in expansion medium was studied by flow cytometry monitoring the expression of characteristic hMSCs markers, and revealed that cells were losing their characteristic surface markers on these supports. Cell morphology was assessed by scanning electron microscopy (SEM). Alkaline phosphatase activity was also assessed after seven days of culture on expansion medium. On the other hand, osteoblastic differentiation was monitored while culturing in osteogenic medium after cells reached confluence. Osteocalcin immunocytochemistry and alizarin red assays were performed. We show that flow cytometry is a suitable technique for the study of the differentiation of hMSC seeded onto biomaterials, giving a quantitative reliable analysis of hMSC-associated markers. We also show that electrosprayed piezoelectric poly(vinylidene fluoride) is a suitable support for tissue engineering purposes, as hMSCs can proliferate, be viable and undergo osteogenic differentiation when chemically stimulated.

Control of lice infestation in horses using a 10 mg/mL deltamethrin topical application

Background

Two open-controlled studies evaluated the tolerance and the efficacy of a 10 mg/mL deltamethrin-based pour-on solution (Deltanil®; Virbac, France) in treating (study 1) and preventing (study 2) natural Damalinia equi infestations in horses. In study 1, seven adult horses received 10 mL of the solution from mane to tail head on day 0 (D0). Four adult horses, living separately, served as non-treated controls. All were naturally infected. Lice burden was recorded by counting the number of live parasites, bilaterally, over seven anatomic regions. Lesional score was based on alopecia, crusts, papules/pustules, nodules/plaques, scales and wounds, each assessed on a 0–3 scale. Evaluation was performed on D0 and subsequently weekly until D56 in treated horses and on D0 and D56 in control horses. In study 2, six adult horses free of parasites were similarly treated on D-2 and D30. Two adult horses, naturally infested with D. equi and left untreated, were mixed with the treated horses from D0 to D60. Evaluation was performed similarly to study 1 on all horses, fortnightly until D60.

Results

No adverse event was recorded in either study. In study 1, parasite and lesional scores of control horses were maintained on D56. Parasite scores of the treated horses were reduced by 98% on D7 and 100% from D15 to D56 (mean [SD]: D0 44 [58.4]). Lesional score in treated horses was reduced by 24, 82, 47, 91, 96, 93, 93 and 100% on D7, 15, 21, 28, 35, 42, 50 and 56, respectively (mean [SD]: D0 3.1 [1.8]).

In study 2, the lice populations remained high in the two control horses throughout the study (max mean [SD]: D0 159 [151.3], min D45 34 [39.6]). On treated animals, all parasite counts were negative except on D15 (one louse found). The protection rate was 99.7% on D15 and 100% from D30 to D60.

Conclusions

A single application of the 10 mg/mL deltamethrin preparation was effective and safe in the treatment and in the prevention of lice infestation in these horses. It was also effective in preventing new infestations for one month.

Jonathas de Andrade: Arte tecendo memórias na interface rural-urbano brasileira

Interesses por pesquisa etnográfica sobre a paisagem motivam esse artigo. O qual criticamente dá aconhecer O Peixe, vídeo de Jonathas de Andrade fortemente inspirado no cotidiano de pescadores artesanais do nordeste brasileiro. O comentário sobre o loop que registra inusitado contato entre dois tipos de seres na foz do rio São Francisco é realizado a partir de impressões recolhidas na 32ª Bienal de São Paulo. O texto inclui ainda subsídios obtidos em entrevista, entre outros elementos que permitem informar as referências teóricas e motivações da trajetória artística do autor. A contribuição ao fim argumenta a favor da possibilidade de diálogo entre o conjunto dessa obra artística e iniciativas de pesquisa no campo das ciências sociais.Palavras-chave: Cinema. Documentário. Humano. Animal. Paisagem.Jonathas de Andrade: art weaving memories at the brazilian rural-urban interface.  AbstractInterest into ethnographic landscape research motivate this article, which dispose critical appreciation about O Peixe (The Fish),  Jonathas de Andrade’s video that is strongly inspired in the everyday life of artisanal fisherman of brazilian northeast region. Comments are made about loop that register unprecedented contact between two kinds of beings on the São Francisco river’s delta, from impressions that stem from exhibition on the 32ª Bienal de São Paulo. Text also includes information from an interview with the author, besides other elements that allow us to inform about theoretical references and motivations of his artistical trajectory. The contribution also finally argues towards dialogic possibility between the whole of this artistic authorial work and research initiatives of social sciences field. Key words:Cinema. Documentary. Human. Animal. Landscape.