Novel scaffolds for tissue engineering of human skeletal muscles

Tissue engineering is a multidisciplinary approach aimed at producing new organs and tissues for implantation in order to circumvent the limitations imposed by current techniques such as surgical tissue transfer. Structure begets function and highly ordered skeletal muscle (SkM) consists of elongated, multinucleate muscle cells (fibres) that are arranged in bundles surrounded by connective tissue sheaths. It is therefore of no surprise that tissue engineered SkM complexes are often designed around fibre containing scaffolds. This work is the natural continuation of strategies introduced at TCES 200

Come il mondo ha cambiato i social media

Come il mondo ha cambiato i social media è il volume complessivo di comparazione dei risultati di un’ampia indagine etnografica, coordinata da Daniel Miller, dall’eloquente titolo “Why We Post”. Nove ricercatori, incluso Miller, hanno trascorso 15 mesi sul campo, in diversi paesi del mondo (Italia del sud, Turchia sudorientale, due siti in Cina, area rurale e area industriale, Trinidad, Inghilterra, India del sud, Cile settentrionale e Brasile) a osservare e studiare, con un approccio etnografico, i modi in cui le persone usano i social media. È un fatto indiscutibile che i social sono entrati nella nostra vita con prepotenza, in modo capillare, per certi aspetti invasivo. Con un linguaggio fluido, talvolta anche colloquiale, il lettore è condotto all’interno di un ambito che gli sembra di conoscere, se non altro perché ne siamo tutti, più o meno, utenti, scoprendo però quanto di valori, di comportamenti culturalmente codificati, di ‘polizia morale’ ci sia dentro i social media. L’approccio qui presentato parte infatti da un’idea un po’ diversa rispetto a quelle più diffuse, e avvalorata nel corso della ricerca: se è indubbio che i social media hanno cambiato il mondo, la questione più interessante riguarda però il modo in cui il mondo li ha cambiati

உலகம் சமூக ஊடகங்களை எப்படி மாற்றியிருக்கிறது

ஒன்பது மானுடவியலாளர்கள் பிரேசில், சீனா, இந்தியா, துருக்கி, இங்கிலாந்து, சிலி, டிரினிடாட், இத்தாலி போன்ற ஒன்பது வெவ்வேறு சமூகங்களில் 15 மாதங்களை தங்கியிருந்து நடத்திய ஆய்வின் கண்டுபிடிப்புகளை ஆராயும் "நாம் ஏன் பதிவிடுகிறோம்" என்ற புத்தக வரிசையின் முதல் புத்தகம் தான் உலகம் சமூக ஊடகங்களை எப்படி மாற்றியிருக்கிறது என்ற இந்தப் புத்தகம். இது மேற்கூறிய ஆராய்ச்சியின் முடிவுகளை தொகுத்து வழங்கியும், அரசியல், கல்வி, பாலினம், வணிகம் ஆகியவற்றின் மீது சமூக ஊடகங்களின் தாக்கத்தைப் பற்றி ஆராய்ந்தும், ஒரு ஒப்பீட்டு ஆய்வினை வழங்குகிறது. காட்சிக்குரிய தகவல் பரிமாற்றத்தின் மீதான அதிக முக்கியத்துவத்தின் விளைவுகள் என்ன? நாம் அதிக தனிமையானவர்களாக ஆகிவருகிறோமா அல்லது அதிக சமூகமயமானவர்களாக ஆகிவருகிறோமா? பொதுநோக்கிய சமூக ஊடகங்கள் ஏன் மிகவும் பழமைவாதம் நிறைந்ததாக இருக்கிறது? நிகழ்நிலையில் உள்ள சமத்துவத்தால், இயல்புநிலையில் உள்ள சமத்துவமின்மையை ஏன் மாற்ற முடியவில்லை? மீம்கள் எப்படி இணையத்தின் மரபுக் காவலர்களாக மாறின? போன்றவை தான் அவை. செயல்திட்டத்தை கல்விக் கட்டமைப்பு மற்றும் கண்டுபிடிப்புகளுக்கு பொறுப்பேற்க உதவும் கருத்தியல் கூறுகள் ஆகியவற்றிற்கான அறிமுகவுரையின் துணையுடன், இந்தப் புத்தகம், சமூக ஊடகங்கள் போன்ற எங்குமுளத்தன்மையுள்ள, மிகவும் நெருக்கமான ஒன்றை புரிந்து கொண்டு பாராட்ட ஒரே வழி, அதில் பதிவிடும் மக்களின் வாழ்வில் மூழ்கிப் பார்ப்பது தான் என்று வாதிடுகிறது. அப்போது தான் நம்மால், உலகெங்கிலும் உள்ள மக்கள் சமூக ஊடகங்களை எவ்வாறு எதிர்பாராத வழிகளில் மாற்றியிருக்கின்றனர் என்று கண்டறிந்து அதன் விளைவுகளை எடைபோட முடியும்

Como o Mundo Mudou as Mídias Sociais

Como o Mundo as Mídias Sociais é o primeiro livro da Why We Post, uma série de livros que investiga as descobertas de nove antropólogos, que passaram 15 meses vivendo em comunidades em diferentes partes do mundo, incluindo Brasil, Chile, China, Inglaterra, Índia, Itália, Trinidad e Turquia. Este livro oferece uma análise comparativa que resume os resultados da pesquisa e a análise do impacto das mídias sociais sobre política e gênero, educação e comércio. Qual é o resultado do aumento da ênfase na comunicação visual? Estamos nos tornando mais individualistas ou mais sociais? Por que as mídias sociais públicas são tão conservadoras? Por que a igualdade na internet não consegue anular a desigualdade? Como os memes se tornaram a polícia moral da internet? Apoiado por uma introdução à estrutura acadêmica do projeto e aos termos teóricos que ajudam a analisar as descobertas, o livro argumenta que a única maneira de se apreciar e entender algo tão privado e ubíquo como as mídias sociais deve se dar a partir da imersão nas vidas das pessoas que ali postam. Só então podemos descobrir como diferentes indivíduos em todo o mundo já transformaram as mídias sociais de maneiras tão inesperadas e avaliar suas conseqüências

Retinoic Acids Potentiate BMP9-Induced Osteogenic Differentiation of Mesenchymal Progenitor Cells

As one of the least studied bone morphogenetic proteins (BMPs), BMP9 is one of the most osteogenic BMPs. Retinoic acid (RA) signaling is known to play an important role in development, differentiation and bone metabolism. In this study, we investigate the effect of RA signaling on BMP9-induced osteogenic differentiation of mesenchymal progenitor cells (MPCs).Both primary MPCs and MPC line are used for BMP9 and RA stimulation. Recombinant adenoviruses are used to deliver BMP9, RARalpha and RXRalpha into MPCs. The in vitro osteogenic differentiation is monitored by determining the early and late osteogenic markers and matrix mineralization. Mouse perinatal limb explants and in vivo MPC implantation experiments are carried out to assess bone formation. We find that both 9CRA and ATRA effectively induce early osteogenic marker, such as alkaline phosphatase (ALP), and late osteogenic markers, such as osteopontin (OPN) and osteocalcin (OC). BMP9-induced osteogenic differentiation and mineralization is synergistically enhanced by 9CRA and ATRA in vitro. 9CRA and ATRA are shown to induce BMP9 expression and activate BMPR Smad-mediated transcription activity. Using mouse perinatal limb explants, we find that BMP9 and RAs act together to promote the expansion of hypertrophic chondrocyte zone at growth plate. Progenitor cell implantation studies reveal that co-expression of BMP9 and RXRalpha or RARalpha significantly increases trabecular bone and osteoid matrix formation.Our results strongly suggest that retinoid signaling may synergize with BMP9 activity in promoting osteogenic differentiation of MPCs. This knowledge should expand our understanding about how BMP9 cross-talks with other signaling pathways. Furthermore, a combination of BMP9 and retinoic acid (or its agonists) may be explored as effective bone regeneration therapeutics to treat large segmental bony defects, non-union fracture, and/or osteoporotic fracture

Definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis: Tokyo Guidelines

This article discusses the definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis. Acute cholangitis and cholecystitis mostly originate from stones in the bile ducts and gallbladder. Acute cholecystitis also has other causes, such as ischemia; chemicals that enter biliary secretions; motility disorders associated with drugs; infections with microorganisms, protozoa, and parasites; collagen disease; and allergic reactions. Acute acalculous cholecystitis is associated with a recent operation, trauma, burns, multisystem organ failure, and parenteral nutrition. Factors associated with the onset of cholelithiasis include obesity, age, and drugs such as oral contraceptives. The reported mortality of less than 10% for acute cholecystitis gives an impression that it is not a fatal disease, except for the elderly and/or patients with acalculous disease. However, there are reports of high mortality for cholangitis, although the mortality differs greatly depending on the year of the report and the severity of the disease. Even reports published in and after the 1980s indicate high mortality, ranging from 10% to 30% in the patients, with multiorgan failure as a major cause of death. Because many of the reports on acute cholecystitis and cholangitis use different standards, comparisons are difficult. Variations in treatment and risk factors influencing the mortality rates indicate the necessity for standardized diagnostic, treatment, and severity assessment criteria

2013 WSES guidelines for management of intra-abdominal infections

Peer reviewe

Nickel-based amorphous alloys with Cr/V additions for the hydrogen evolution reaction in alkaline solution

grantor: University of TorontoAlloy compositions of Ni55-xCo25B 20Crx and Ni55-yCo25B20 Vy where x = 1-20 and y = 1-10 were produced using the melt spinning technique. The amorphous nature of the alloys was confirmed by X-ray diffraction and their atomic composition verified by Inductively Coupled Plasma Spectroscopy. Differential Scanning Calorimetry was used to determine their thermal characteristics. The electrocatalytic activity of the alloys was measured using a steady state potentiostatic technique. Polarization curves yielded data on the exchange current density and the Tafel slope values for the alloys. As the concentration of chromium and vanadium increased in the alloys, from 1 to 20 at.% and 1 to 10 at.%, the exchange current density increased from 4 to 16 * 10-5 A/cm2 and from 3 to 6.6 * 10-5 A/cm2 respectively. Increased Cr and V concentrations increased the Tafel slopes from 155 to 210 mV/dec and from 145 to 165 mV/dec respectively, in the low overpotential range.M.A.Sc