GLP-1 Analogue-Loaded Glucose-Responsive Nanoparticles as Allies of Stem Cell Therapies for the Treatment of Type I Diabetes.

Type 1 diabetes (T1D) is characterized by insufficient insulin secretion due to ß-cell loss. Despite exogenous insulin administration being a lifesaving treatment, many patients still experience severe glycemic lability. For these patients, a ß-cell replacement strategy through pancreas or pancreatic islet transplantation is the most physiological approach. However, donors' scarcity and the need for lifelong immunosuppressive therapy pose some challenges. This study proposes an innovative biomimetic pancreas, comprising ß- and α-cells differentiated from human induced pluripotent stem cells (hiPSCs) embedded in a biofunctional matrix with glucose-responsive nanoparticles (NPs) encapsulating a glucagon-like peptide 1 (GLP-1) analogue, which aims to enhance the glucose responsiveness of differentiated ß-cells. Herein, glucose-sensitive pH-responsive NPs encapsulating exenatide or semaglutide showed an average size of 145 nm, with 40% association efficiency for exenatide-loaded NPs and 55% for semaglutide-loaded NPs. Both peptides maintained their secondary structure after in vitro release and showed a similar effect on INS-1E cells' insulin secretion. hiPSCs were differentiated into ß- and α-cells, and insulin-positive cells were obtained (82%), despite low glucose responsiveness, as well as glucagon-positive cells (17.5%). The transplantation of the developed system in diabetic mice showed promising outcomes since there was an increase in the survival rate of those animals. Moreover, diabetic mice transplanted with cells and exenatide showed a decrease in their glucose levels. Overall, the biomimetic pancreas developed in this work showed improvements in diabetic mice survival rate, paving the way for new cellular therapies for T1D that explore the synergy of nanomedicines and stem cell-based approaches.

The Material World of 3D-Bioprinted and Microfluidic-Chip Models of Human Liver Fibrosis.

Biomaterials are extensively used to mimic cell-matrix interactions, which are essential for cell growth, function, and differentiation. This is particularly relevant when developing in vitro disease models of organs rich in extracellular matrix, like the liver. Liver disease involves a chronic wound-healing response with formation of scar tissue known as fibrosis. At early stages, liver disease can be reverted, but as disease progresses, reversion is no longer possible, and there is no cure. Research for new therapies is hampered by the lack of adequate models that replicate the mechanical properties and biochemical stimuli present in the fibrotic liver. Fibrosis is associated with changes in the composition of the extracellular matrix that directly influence cell behavior. Biomaterials could play an essential role in better emulating the disease microenvironment. In this paper, the recent and cutting-edge biomaterials used for creating in vitro models of human liver fibrosis are revised, in combination with cells, bioprinting, and/or microfluidics. These technologies have been instrumental to replicate the intricate structure of the unhealthy tissue and promote medium perfusion that improves cell growth and function, respectively. A comprehensive analysis of the impact of material hints and cell-material interactions in a tridimensional context is provided.

Characterization of a human lesioned-skin model to assess the influence of skin integrity on drug permeability.

The stratum corneum (SC) is the skin's outermost layer, organized by clusters of corneocytes among a lipid matrix, acting as a barrier. This "brick and mortar" organization is modified in many skin diseases. We proposed a lesioned-skin model for assessing the permeability of topical formulations and the impact of skin integrity on the permeability of molecules. We anticipate that removal of the SC compromises the skin barrier function, making it more permeable, affecting the biopharmaceutics of topical formulations. By stripping with 25 strips (Corneofix®), the thickness of the SC was considerably reduced, exposing the viable epidermis. Transversal and upper views of the skin by electronic microscopy and histology confirm the removal of the SC. After, we evaluated the permeability of tacrolimus (Protopic®, 0.1 % and 0.03 %) by HPLC-UV. The non-lesioned skin presented 20-25 % of tacrolimus in the SC and no drug permeated through the skin's inner layers. Contrary, the lesioned-skin model allowed the permeation of tacrolimus to the epidermis, dermis, and also in the receptor medium. These results highlight the importance of using diseased skin tissue as opposed to normal skin when assessing the permeability of pharmaceutical formulations for local topical delivery, closely mimicking the occurred events in clinical scenario.

From pluripotent stem cells to bioengineered islets: A challenging journey to diabetes treatment.

Type 1 diabetes mellitus affects 45 million people worldwide and its prevalence is rapidly increasing. It derives from a lack of insulin production by the pancreas, which leads to elevated blood sugar levels. Current treatments rely on the administration of exogenous insulin, but they do not replicate the precise control of glycemia by the pancreas. Whole pancreas and pancreatic islet transplantation restore endogenous insulin secretion in response to blood glucose levels. However, both are limited by the lack of donors and the need for immunosuppressive therapy. Pluripotent stem cells are a virtually unlimited cell source and can be differentiated to the desired cell types. Moreover, induced pluripotent stem cells may be derived from the patient's cells, which could prevent graft rejection. Several protocols report the differentiation of pluripotent stem cells into insulin-producing cells that, after transplantation, can restore glycemic control. Such protocols are based on the embryonic development of the pancreas, highlighting the importance of understanding the different stages and signaling pathways involved in this process. Once the main hurdles to stem cell-based therapies are overcome, translation to clinical practice will greatly improve the quality of life of people with type 1 diabetes mellitus.

Sobrelotação do Serviço de Urgência - Estratégias de Redução Percecionadas por Enfermeiros / Overcrowding in the Emergency Department - Reduction Strategies Perceived by Nurses

Enquadramento: A sobrelotação nos serviços de urgência hospitalar é um problema existente nos hospitais portugueses. Os SU são um dos maiores pilares dos hospitais, dotados de uma grande carga de complexidade, com o objetivo major de prestar cuidados imediatos, urgentes e emergentes a todo o tipo de indivíduos. Os Enfermeiros lidam com esta realidade diariamente, necessitando de estratégias de redução da sobrelotação para melhorar os cuidados prestados. Objetivos: Identificar as estratégias que possam ser consideradas válidas e aplicáveis nos SU portugueses, na redução da sobrelotação. Validar a escala das estratégias de redução de sobrelotação do serviço de urgência (EERSSU). Relacionar as estratégias encontradas com a idade, sexo, formação académica/profissional, tempo de exercício profissional, tempo de exercício profissional em SU e formação em TM dos participantes. Metodologia: Trata-se de um estudo quantitativo, correlacional, com uma amostra de 228 enfermeiros a exercerem funções em serviços de urgência portugueses. Foi aplicada uma escala previamente existente acerca das estratégias de redução da sobrelotação, para avaliação do nível de concordância, com limites de 1 a 5, (1-discordo totalmente, 5-concordo plenamente. Foi avaliada a existência de diferenças estatisticamente significativas e correlações entre a variável principal em estudo (sobrelotação) e as variáveis independentes. Resultados: A EERSSU apresenta boas características psicométricas, com α de Cronbach de 0.911 e KMO,851. A validade fatorial levou a 5 fatores: Gestão de Processos Clínicos, Gestão de Competências, Práticas de Controlo da Qualidade, Gestão de Recursos Físicos e Humanos e Controlo de Acesso de Doentes, que explicam 51.9% da variância total. As estratégias de redução que obtiveram maiores níveis de concordância foram: criação de protocolos institucionais para a transferência de doentes (M=4.30, DP=0.74), planeamento precoce da alta (M=4.21, DP=0.78), agilização dos tempos de resposta de testes laboratoriais e imagiológicos (M=4.12, DP=0.89) e criação de uma equipa de coordenação para tratar e avaliar doentes, evitando readmissões (M=4.09, DP=0.88). Conclusão: As estratégias percecionadas podem contribuir para a redução da sobrelotação, com o propósito da melhoria da qualidade dos cuidados, da segurança do doente, sendo ferramentas disponíveis para implementação nos serviços de urgência portugueses.

Introduction: The emergency deparment (ED) is a key pillar of the hospital organization, implying high complexity and entailing the need to provide immediate emergency care to all patients. Overcrowding in such department is a reality in many Portuguese hospitals. Nursing staff dealing with this issue need strategies to cope with the reduction of overcrowding to improve patient care. Objectives: To identify valid and applicable strategies to reduce overcrowding in the Portuguese EDs. To validate a score of strategies to reduce overcrowding in the ED. To relate identified strategies with the studied population characteristics namely, age, gender, professional abilities, time of practice as a nurse and as an ED nurse and triage competencies. Methodology: We carried out a quantitative correlational study using an existing score as means of query applied to nurses working in Portuguese EDs. The applied score concerning strategies to reduce overcrowding, evaluates the level of agreement from one (totally disagree) through five (totally agree). We carried out statistical analysis between the main variable of the study (overcrowding) and the independent variables. Results: The Scale of Overcrowding Reduction Strategies in the Emergency Department revealed good psychometric characteristics: Cronbach α 0.911 and KMO 0,851. Its factor validity points to five factors: clinical file management, skill management, quality control management, human resources management and patient access control accounting for 51.9% of the total variance. The choice of strategies revealed higher levels of agreement in the creation of institutional protocols for patient transfer (M=4.30, SD=0.74), discharge planning (M=4.21, SD=0.78), expedite laboratory tests and imagological exams (M=4.12, SD=0.89) and creation of a dedicated coordination team for patient assessment, avoiding readmissions (M=4.09, SD=0.88). Conclusion: The perceived strategies may contribute to the reduction of overcrowding, with the intention of improving quality of care and patient safety, as available tools to implement on Portuguese EDs.

An Anticaffeine Antibody-Oligonucleotide Conjugate for DNA-Directed Immobilization in Environmental Immunoarrays.

The development of fast and cheap high-throughput platforms for the detection of environmental contaminants is of particular importance to understand the human-related impact on the environment. The application of DNA-directed immobilization (DDI) of IgG molecules is currently limited to the clinical diagnostics scenario, possibly because of the high costs of production of such addressable platforms. We here describe the efficient and specific hybridization of an antibody-oligonucleotide conjugate to a short 12-mer capture probe. The specific antibody used is a monoclonal antibody against caffeine, a stimulant and important anthropogenic marker. With this work, we hope to contribute to broadening the application potential of DDI to environmental markers in order to develop cheaper and more stable high-throughput screening platforms for standard routine analysis of pollutants in a variety of complex matrices.

Exuberant liver adenomatosis presenting with iron deficiency anemia.

Intratumoral or intraperitoneal hemorrhage is a recognized complication of liver adenomatosis. We report a case of multifocal massive liver adenomatosis presenting as chronic iron deficiency anemia. Clinicians' awareness about this atypical presentation not highlighted in the literature is important to allow timely diagnosis and surgical intervention to prevent fatal complications.

[Antibiotic treatment of uncomplicated cystitis in non-pregnant women up to menopause]. / Tratamento antibiótico da cistite não complicada em mulheres não grávidas até à menopausa.

OBJECTIVES: To review treatment recommendations for UC in non-pregnant women up to menopause, using the scale Strength of Recommendation Taxonomy (SORT). DATA SOURCE: Medline, UpToDate, Cochrane, Bandolier, Database of Abstracts of Reviews of Effects, National Guideline Clearinghouse, Guidelines Finder and the website of the Portuguese Urology Association. METHODS: Research of systematic reviews (SR), meta-analyses (MA), randomized controlled trials (RCT) and guidelines, published in english and portuguese, between 2000 and 2008. RESULTS: Two MA, two SR, four RCT and six Guidelines were included. Three-day treatments are preferable to those of seven to ten days, mainly because of higher compliance and lower cost and incidence of adverse effects (A). Longer regimens are acceptable for bacterial eradication. Trimethoprim/sulfamethoxazole (TMP/SMX) is the option where resistance levels are lower than 10-20% (A). As a clinical and microbiological alternative, evidence seems to point out the Fluoroquinolones (FQ) (C) which are equally efficient among themselves, although showing different safety profiles. CONCLUSIONS: In case of allergy or high resistance to TMP/SMX, FQ are the most efficacious alternative, both prescriptions recommended for three days. However, due to the risk of worsening resistance to FQ, the options consist on nitrofurantoin and fosfomicine.