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Engineered tissues can be used to model human pathophysiology and test the efficacy and safety of drugs. Yet, to model whole-body physiology and systemic diseases, engineered tissues with preserved phenotypes need to physiologically communicate. Here we report the development and applicability of a tissue-chip system in which matured human heart, liver, bone and skin tissue niches are linked by recirculating vascular flow to allow for the recapitulation of interdependent organ functions. Each tissue is cultured in its own optimized environment and is separated from the common vascular flow by a selectively permeable endothelial barrier. The interlinked tissues maintained their molecular, structural and functional phenotypes over 4 weeks of culture, recapitulated the pharmacokinetic and pharmacodynamic profiles of doxorubicin in humans, allowed for the identification of early miRNA biomarkers of cardiotoxicity, and increased the predictive values of clinically observed miRNA responses relative to tissues cultured in isolation and to fluidically interlinked tissues in the absence of endothelial barriers. Vascularly linked and phenotypically stable matured human tissues may facilitate the clinical applicability of tissue chips.

Tese de doutoramento em Medicina, Cardiomiócitos diferenciados de células estaminais pluripotentes induzidas são uma ferramenta única na recapitulação de doenças cardiovasculares humanas e no estudo de perfis farmacológicos de novas drogas. Aqui apresentamos três projetos que incorporam tecnologias emergentes com estes cardiomiócitos para demonstrar meios seguros e eficazes no diagnóstico de doenças cardíacas e no estudo de drogas. No primeiro estudo, nós validamos a utilização de perfis de contração obtidos a partir de um teste sem contacto ou rótulos para classificar de forma confiável cardiomiócitos saudáveis e doentes. Vários algoritmos de aprendizagem de máquina (machine learning) supervisionada classificaram devidamente células cardíacas utilizando parâmetros de contração obtidos a partir de vídeos de campo claro de 20 segundos. Nós demonstramos que cardiomiócitos podem ser devidamente classificados com base em perfis de contração obtidos de modo não-invasivo, e que algoritmos de machine learning podem ser utilizados como uma ferramenta de triagem em estudos de contração cardíaca de um modo automático, de alta complexidade, e de alto rendimento. No segundo estudo, nós otimizamos birreatores para a formação e maturação de tecidos cardíacos, e desenvolvemos um sistema de órgãos-em-chips (organs-on-chips) em polissulfona para avaliar a eficácia e segurança de linsitinib, uma droga anticancerígena. Tecidos cardíacos e de tumor ósseo cultivados em isolamento replicaram outros modelos pré-clínicos que mostraram linsitinib como uma droga eficaz, mas causando cardiotoxicidade severa. Quando ambos os tecidos foram cultivados de modo integrado, eles replicaram os resultados de um estudo clínico, que confirmaram que linsitinib é uma droga ineficaz e que causa cardiotoxicidade moderada. Nós demonstramos que o nosso organs-on-chips consegue predizer resultados clínicos. No terceiro estudo, o organs-on-chips foi utilizado para modelar a farmacocinética (PK) e a farmacodinâmina (PD) de doxorubicin, uma droga anticancerígena. Nós desenvolvemos um modelo in silico do chip para simular a distribuição e metabolismo da droga. Este modelo computacional previu a PK da doxorubicin no chip e observamos também correlações significativas entre o perfil de PD no chip e dados previamente reportados. Nós demonstramos a capacidade de organs-on-chips em modelar perfis farmacológicos de drogas. A integração de metodologias experimentais com tecnologias emergentes, como as discutidas nesta dissertação, tem o potencial de ajudar no desenvolvimento de modelos cada vez mais complexos para o estudo de doenças humanas e a avaliação de novos regimes terapêuticos., Cardiomyocytes differentiated from human induced pluripotent stem cells provide a unique tool for modeling human cardiovascular disease and assessing the pharmacological profiles of new drugs. They have been used in various approaches, ranging from two-dimensional cell cultures to three-dimensional tissues. Here we show three projects which incorporate emerging technologies with these cardiomyocytes to demonstrate a safer and more efficient means for the diagnosis of cardiac diseases and for the study of therapeutic agents. In the first study, we validated the utility of contractility profiles obtained from a noncontact, label-free assay to reliably classify healthy and diseased cardiomyocytes. Several supervised machine learning algorithms properly classified the cardiac cells using contractility parameters obtained from 20-second long brightfield videos. We demonstrated that cardiomyocytes can be properly classified based on noninvasive measurements of their contractile profiles, and machine learning algorithms can be utilized as an automated, high-throughput, and high complexity screening tool in studies of cardiac contractility. In the second study, we optimized bioreactors for the generation and maturation of human cardiac muscle tissues, and designed a polysulfone-based organs-on-chips system to assess the efficacy and safety of linsitinib, an anti-cancer drug. Heart and bone tumor tissues cultured in isolation replicated other preclinical models which showed linsitinib to be an effective anti-cancer drug while causing severe cardiotoxicity. When both tissues were cultured in an integrated setting, they recapitulated the results of a clinical trial, which confirmed linsitinib to be ineffective in inhibiting tumor growth and only causing mild cardiotoxicity. We showed our organs-on-chips system to better predict clinical outcomes at the preclinical stage. In the third study, an organs-on-chips system developed in our lab was used to model the pharmacokinetics (PK) and pharmacodynamics (PD) of doxorubicin, an anti-cancer drug. We then developed an in silico model of the chip for computational simulations of the drug’s distribution and metabolism. This computational model predicted doxorubicin’s PK in the chip. We also observed significant correlations between the PD profiles in the chip and previously reported data. We demonstrate the capability of organs-on-chips in preclinical modeling of pharmacological drug profiles. Future integration of experimental methodologies with emerging technologies, such as the ones discussed in this dissertation, has the potential to aid in the development of increasingly complex models for studying human disease as well as for evaluating new therapeutic regimens., Financial support was provided by Fundaçāo para a Ciência e Tecnologia fellowship PD/BD/105819/2014, awarded through the University of Minho MD/PhD Program.

Traditional drug screening models are often unable to faithfully recapitulate human physiology in health and disease, motivating the development of microfluidic organs-on-a-chip (OOC) platforms that can mimic many aspects of human physiology and in the process alleviate many of the discrepancies between preclinical studies and clinical trials outcomes. Linsitinib, a novel anti-cancer drug, showed promising results in pre-clinical models of Ewing Sarcoma (ES), where it suppressed tumor growth. However, a Phase II clinical trial in several European centers with patients showed relapsed and/or refractory ES. We report an integrated, open setting, imaging and sampling accessible, polysulfone-based platform, featuring minimal hydrophobic compound binding. Two bioengineered human tissues – bone ES tumor and heart muscle – were cultured either in isolation or in the integrated platform and subjected to a clinically used linsitinib dosage. The measured anti-tumor efficacy and cardiotoxicity were compared with the results observed in the clinical trial. Only the engineered tumor tissues, and not monolayers, recapitulated the bone microenvironment pathways targeted by linsitinib, and the clinically-relevant differences in drug responses between non-metastatic and metastatic ES tumors. The responses of non-metastatic ES tumor tissues and heart muscle to linsitinib were much closer to those observed in the clinical trial for tissues cultured in an integrated setting than for tissues cultured in isolation. Drug treatment of isolated tissues resulted in significant decreases in tumor viability and cardiac function. Meanwhile, drug treatment in an integrated setting showed poor tumor response and less cardiotoxicity, which matched the results of the clinical trial. Overall, the integration of engineered human tumor and cardiac tissues in the integrated platform improved the predictive accuracy for both the direct and off-target effects of linsitinib. The proposed approach could be readily extended to other drugs and tissue systems.

This study aims to evaluate the occurrence of polypharmacy in elderly assisted by the Hospital Dia do Idoso (HDI) of Anapolis, Goias. The research is descriptive quantitative with cross-sectional design with 551 elderly from Hospital Dia do Idoso, between the months of October 2015 to January 2016. The sample is composed of elderly attended at general clinic of HDI. The data were collected from medical records of people aged 60 and over who were registered in the unit. The variables studied were age, gender, month of service, number of medications used and which one of these were classified as potentially inappropriate by the Beers-Fick criteria. The analysis was done with the Statistical Package for Social Sciences (SPSS). Among the elderly who attend this health facility 70.4% are women and 29.6% men. Of these, 38.8% use five or more medications, which are classified as polypharmacy. Furthermore, there is a tendency to increase the number of drugs used as the age advances. By adopting the Beers-Fick criteria, it was observed that 21.0% used potentially inappropriate medications and 20.3% used unrecommended drugs. Among these stands out the Calcium Channel Blockers to be the most frequently used. The elderly from HDI follow the trends found in the literature, even though it has a higher percentage of polypharmacy. Such finding is explained by the fact that the sample is located in a center of exclusive service to the elderly. O presente estudo tem por objetivo avaliar a ocorrência de polifarmácia em idosos assistidos pelo Hospital Dia do Idoso (HDI) de Anápolis, Goiás. A pesquisa é quantitativa descritiva com delineamento transversal com 551 idosos do HDI, entre os meses de outubro de 2015 a janeiro de 2016. A amostra é composta por idosos atendidos na Clínica Médica do Hospital Dia do Idoso (HDI). Os dados foram coletados a partir dos prontuários de pessoas com 60 anos ou mais e que estavam cadastrados na unidade. As variáveis estudadas foram sexo, idade, mês do atendimento, número de medicamentos utilizados e quais destes se classificavam como potencialmente inapropriados, segundo o critério de Beers-Fick. A análise foi feita com o programa Statistical Package for the Social Sciences (SPSS). Entre os idosos que frequentam essa unidade de saúde 70,4% são mulheres e 29,6% homens. Destes, 38,8% usam cinco ou mais medicamentos, ou seja, são classificados em polifarmácia. Além disso, constatou-se uma tendência a aumentar o número de medicamentos utilizados à medida que a idade avança. Ao adotar os Critérios de Beer-Fick, observou-se que 21,0% utilizavam medicamentos potencialmente inapropriados e 20,3% utilizavam medicamentos não recomentados. Dentre estes se destacam os Bloqueadores dos Canais de Cálcio por serem os mais utilizados. Os idosos do Hospital Dia do Idoso seguem as tendências encontradas na literatura, embora apresentem uma maior porcentagem de polifarmácia. Achado que se baseia no fato da amostra estar localizada em um centro de atendimento exclusivo a idosos.

With the advance of technology, several equipment that were expensive in the past are relatively cheap nowadays. One of this equipment is the Software Defined Radio (SDR). SDRs can transform expensive equipment available on the market into simple, cheap and easy to build computer applications. One of latter is the Automatic Information System (AIS). Because AIS is an equipment of great importance to the safety of navigation and it's not compulsory for small vessels, if there's a way of making it cheaper and accessible for everyone, it would have many advantages. On this paper we propose a creation of a Low-Cost AIS Transmitter using the SDR technology and open-source software.

Nowadays, oceans represent a very important part of our economies, as ways of communication between countries and because of the resources they contain, making their safety and protection major concerns that we all face. Because of this, there are several threats which must be dealt with. One of these threats are the Chemical, Biological, Radiological and Nuclear (CBRN) agents. In this framework, the development of technologies with the potential to increase the capabilities for detection of pollutants or toxic materials and situational awareness plays a significant role in the case of events in the scope of maritime accidents, pollution or port safety and security. These scenarios can pose substantial challenges to the operations, due to their complexity, and the use of unmanned aerial vehicles (UAV) is increasingly becoming ubiquitous in this context. This paper is focused in operation environment demonstrations, which aimed to validate the operational feasibility of the concept simulating two different scenarios; chemical and radiological. The selected scenarios were chosen on a risk probability analysis, being very approximate to a real-life incident. This system was tested, and the validation tests are also represented. It proved to be an asset in CBRN releases, either intentional or non-intentional.

Author Manuscript, The application of tissue-engineering approaches to human induced pluripotent stem (hiPS) cells enables the development of physiologically relevant human tissue models for in vitro studies of development, regeneration, and disease. However, the immature phenotype of hiPS-derived cardiomyocytes (hiPS-CMs) limits their utility. We have developed a protocol to generate engineered cardiac tissues from hiPS cells and electromechanically mature them toward an adult-like phenotype. This protocol also provides optimized methods for analyzing these tissues' functionality, ultrastructure, and cellular properties. The approach relies on biological adaptation of cultured tissues subjected to biomimetic cues, applied at an increasing intensity, to drive accelerated maturation. hiPS cells are differentiated into cardiomyocytes and used immediately after the first contractions are observed, when they still have developmental plasticity. This starting cell population is combined with human dermal fibroblasts, encapsulated in a fibrin hydrogel and allowed to compact under passive tension in a custom-designed bioreactor. After 7 d of tissue formation, the engineered tissues are matured for an additional 21 d by increasingly intense electromechanical stimulation. Tissue properties can be evaluated by measuring contractile function, responsiveness to electrical stimuli, ultrastructure properties (sarcomere length, mitochondrial density, networks of transverse tubules), force-frequency and force-length relationships, calcium handling, and responses to β-adrenergic agonists. Cell properties can be evaluated by monitoring gene/protein expression, oxidative metabolism, and electrophysiology. The protocol takes 4 weeks and requires experience in advanced cell culture and machining methods for bioreactor fabrication. We anticipate that this protocol will improve modeling of cardiac diseases and testing of drugs., NIBIB and NCATS grant EB17103 (G.V.-N.); NIBIB, NCATS, NIAMS, NIDCR, and NIEHS grant EB025765 (G.V.-N.); NHLBI grants HL076485 (G.V.-N.) and HL138486 (M.Y.); NSF grant 16478 (G.V.-N.); the University of Minho MD/PhD program (D.T.); a Japan Society for the Promotion of Science fellowship (K.M.); and the Columbia University Stem Cell Initiative (L.S., M.Y.)

Cardiac tissues generated from human induced pluripotent stem cells (iPSCs) can serve as platforms for patient-specific studies of physiology and disease1-6. However, the predictive power of these models is presently limited by the immature state of the cells1, 2, 5, 6. Here we show that this fundamental limitation can be overcome if cardiac tissues are formed from early-stage iPSC-derived cardiomyocytes soon after the initiation of spontaneous contractions and are subjected to physical conditioning with increasing intensity over time. After only four weeks of culture, for all iPSC lines studied, such tissues displayed adult-like gene expression profiles, remarkably organized ultrastructure, physiological sarcomere length (2.2 µm) and density of mitochondria (30%), the presence of transverse tubules, oxidative metabolism, a positive force-frequency relationship and functional calcium handling. Electromechanical properties developed more slowly and did not achieve the stage of maturity seen in adult human myocardium. Tissue maturity was necessary for achieving physiological responses to isoproterenol and recapitulating pathological hypertrophy, supporting the utility of this tissue model for studies of cardiac development and disease., The authors acknowledge funding support from the National Institutes of Health of the USA (NIBIB and NCATS grant EB17103 (G.V.-N.); NIBIB, NCATS, NIAMS, NIDCR and NIEHS grant EB025765 (G.V.-N.); NHLBI grants HL076485 (G.V.-N.) and HL138486 (M.Y.); Columbia University MD/PhD program (S.P.M., T.C.); University of Minho MD/PhD program (D.T.); Japan Society for the Promotion of Science fellowship (K.M.); and Columbia University Stem Cell Initiative (D.S., L.S., M.Y.). We thank S. Duncan and B. Conklin for providing human iPSCs, M.B. Bouchard for assistance with image and video analysis, and L. Cohen-Gould for transmission electron microscopy services., info:eu-repo/semantics/publishedVersion