Strong Elastic Protein Nanosheets Enable the Culture and Differentiation of Induced Pluripotent Stem Cells on Microdroplets.

Advances in stem cell technologies, revolutionizing regenerative therapies and advanced in vitro testing, require novel cell manufacturing pipelines able to cope with scale up and parallelization. Microdroplet technologies, which have transformed single cell sequencing and other cell-based assays, are attractive in this context, but the inherent soft mechanics of liquid-liquid interfaces is typically thought to be incompatible with the expansion of induced pluripotent stem cells (iPSCs), and their differentiation. In this work, the design of protein nanosheets stabilizing liquid-liquid interfaces and enabling the adhesion, expansion and retention of stemness by iPSCs is reported. Microdroplet microfluidic chips are used to control the formulation of droplets with defined dimensions and size distributions. The resulting emulsions sustain high expansion rates, with excellent retention of stem cell marker expression. iPSCs cultured in such conditions retain the capacity to differentiate into cardiomyocytes. This work provides clear evidence that local nanoscale mechanics, associated with interfacial viscoelasticity, provides strong cues able to regulate and maintain pluripotency, as well as to support commitment in defined differentiation conditions. Microdroplet technologies appear as attractive candidates to transform cell manufacturing pipelines, bypassing significant hurdles paused by solid substrates and microcarriers.

BMP-Binding Polysulfonate Brushes to Control Growth Factor Presentation and Regulate Matrix Remodelling.

Bone morphogenetic proteins (BMPs) are important targets to incorporate in biomaterial scaffolds to orchestrate tissue repair. Glycosaminoglycans (GAGs) such as heparin allow the capture of BMPs and their retention at the surface of biomaterials at safe concentrations. Although heparin has strong affinities for BMP2 and BMP4, two important types of growth factors regulating bone and tissue repair, it remains difficult to embed stably at the surface of a broad range of biomaterials and degrades rapidly in vitro and in vivo. In this report, biomimetic poly(sulfopropyl methacrylate) (PSPMA) brushes are proposed as sulfated GAG mimetic interfaces for the stable capture of BMPs. The growth of PSPMA brushes via a surface-initiated activator regenerated by electron transfer polymerization is investigated via ellipsometry, prior to characterization of swelling and surface chemistry via X-ray photoelectron spectroscopy and Fourier transform infrared. The capacity of PSPMA brushes to bind BMP2 and BMP4 is then characterized via surface plasmon resonance. BMP2 is found to anchor particularly stably and at high density at the surface of PSPMA brushes, and a strong impact of the brush architecture on binding capacity is observed. These results are further confirmed using a quartz crystal microbalance with dissipation monitoring, providing some insights into the mode of adsorption of BMPs at the surface of PSPMA brushes. Primary adsorption of BMP2, with relatively little infiltration, is observed on thick dense brushes, implying that this growth factor should be accessible for further binding of corresponding cell membrane receptors. Finally, to demonstrate the impact of PSPMA brushes for BMP2 capture, dermal fibroblasts were then cultured at the surface of functionalized PSPMA brushes. The presence of BMP2 and the architecture of the brush are found to have a significant impact on matrix deposition at the corresponding interfaces. Therefore, PSPMA brushes emerge as attractive coatings for scaffold engineering and stable capture of BMP2 for regenerative medicine applications.

Un caso de neumonía organizada tras la ruptura intracapsular de implantes mamarios de silicona / A case of organized pneumonia after intracapsular rupture of silicone breast implants

La neumonía organizada es una entidad poco frecuente, caracterizada por la formación de conglomerados fibroblásticos intraalveolares conocidos como cuerpos de Masson, que puede ser criptogénica o secundaria a una respuesta inmunitaria a diversos estímulos, tales como enfermedades hematológicas, autoinmunitarias, exposición a sustancias químicas, fármacos, tóxicos, etc. Detectada y tratada de forma precoz, suele tener una buena respuesta a la corticoterapia, aunque si se diagnostica de forma tardía, la afectación pulmonar puede ser extensa, y, además, si el estímulo antigénico persiste, la respuesta al tratamiento será incompleta. Presentamos el caso clínico de una paciente de 65 años de edad quien hace 18 meses aproximadamente presentó la rotura intracapsular de sus implantes mamarios, 27 años después de su colocación. Con el mismo tiempo de evolución ha desarrollado progresivamente disnea, tos seca y dolor inframamario, habiendo llegado al diagnóstico de neumonía organizada bilateral difusa, asociada a dicha rotura de implantes.

Organizing pneumonia is a rare entity, characterized by the formation of intraalveolar fibroblastic conglomerates known as Masson bodies, which may be cryptogenic or secondary to an immune response to various stimuli, such as hematological, autoimmune diseases, exposure to chemical substances, drugs, toxics, etc. If it is detected and treated early, it usually has a good response to corticosteroid therapy, although if it is diagnosed late, the lung involvement can be extensive, and furthermore, if the antigenic stimulus persists, the response to treatment will be incomplete. We present the clinical case of a 65-year-old patient who had intracapsular rupture of her breast implants approximately 18 months ago, 27 years after their placement. With the same evolution time, she progressively developed dyspnea, dry cough and under mammary pain, having reached the diagnosis of diffuse bilateral organizing pneumonia, associated with implant rupture.

Purification and characterization of Hb 98-114: a novel hemoglobin-derived antimicrobial peptide from the midgut of Rhipicephalus (Boophilus) microplus.

The antimicrobial activity of hemoglobin fragments (hemocidins) has been reported in a variety of models. The cattle tick Rhipicephalus (Boophilus) microplus is a blood sucking arthropod from where the first in vivo-generated hemocidin was characterized (Hb 33-61). In the present work we identified a novel antimicrobial peptide from the midgut of fully engorged R. (B.) microplus females, which comprises the amino acids 98-114 of the alpha subunit of bovine hemoglobin, and was designated Hb 98-114. This peptide was active against several yeast and filamentous fungi, although no activity was detected against bacteria up to 50µM of the synthetic peptide. Hb 98-114 was capable of permeabilizing Candida albicans cell membrane and had a fungicidal effect against this yeast. Circular dichroism (CD) and nuclear magnetic resonance (NMR) experiments showed that Hb 98-114 has a random conformation in aqueous solution but switches to an alpha-helical conformation in the presence of sodium dodecyl sulfate (SDS). This alpha helix adopts an amphipathic structure which may be the mechanism of cell membrane permeabilization. Importantly, Hb 98-114 may play an important role in defending the tick midgut against fungal pathogens and is the first hemocidin with specific antifungal activity to be characterized.

Characterization of proteinases from the midgut of Rhipicephalus (Boophilus) microplus involved in the generation of antimicrobial peptides.

BACKGROUND: Hemoglobin is a rich source of biologically active peptides, some of which are potent antimicrobials (hemocidins). A few hemocidins have been purified from the midgut contents of ticks. Nonetheless, how antimicrobials are generated in the tick midgut and their role in immunity is still poorly understood. Here we report, for the first time, the contribution of two midgut proteinases to the generation of hemocidins. RESULTS: An aspartic proteinase, designated BmAP, was isolated from the midgut of Rhipicephalus (Boophilus) microplus using three chromatographic steps. Reverse transcription-quantitative polymerase chain reaction revealed that BmAP is restricted to the midgut. The other enzyme is a previously characterized midgut cathepsin L-like cysteine proteinase designated BmCL1. Substrate specificities of native BmAP and recombinant BmCL1 were mapped using a synthetic combinatorial peptide library and bovine hemoglobin. BmCL1 preferred substrates containing non-polar residues at P2 subsite and polar residues at P1, whereas BmAP hydrolysed substrates containing non-polar amino acids at P1 and P1'. CONCLUSIONS: BmAP and BmCL1 generate hemocidins from hemoglobin alpha and beta chains in vitro. We postulate that hemocidins may be important for the control of tick pathogens and midgut flora.

Evaluación 3 años después de realizados 61 tratamientos pulporradiculares / An evaluation 3 years after perforing 61 pulporadicular treatments

Se realizan radiografías periapicales por el método de bisección a 47 pacientes que presentaban un total de 61 dientes con tratamientos pulporradiculares realizados con 3 o más años de antelación, con el fin de conocer la efectividad de los mismos y las principales causas que pudieran incidir en los tratamientos fracasados. Se detectaron 13 tratamientos fracasados, lo que representa el 21,3 por ciento de la muestra; además, el 42,6 por ciento de los conductos se encontraban instrumentados parcialmente; esto constituyó la principal causa de fracasos. En sentido general, no se encontraron diferencias apreciables en cuanto a las principales causas expresadas por otros autores (AU)

Evaluación 3 años después de realizados 61 tratamientos pulporradiculares / An evaluation 3 years after performing 61 pulporadicular treatments

Se realizan radiografías periapicales por el método de bisección a 47 pacientes que presentaban un total de 61 dientes con tratamientos pulporradiculares realizados con 3 o más años de antelación, con el fin de conocer la efectividad de los mismos y las principales causas que pudieran incidir en los tratamientos fracasados. Se detectaron 13 tratamientos fracasados, lo que representa el 21,3 por ciento de la muestra; además, el 42,6 por ciento de los conductos se encontraban instrumentados parcialmente; esto constituyó la principal causa de fracasos. En sentido general, no se encontraron diferencias apreciables en cuanto a las principales causas expresadas por otros autores

Paralisia do olhar conjugado lateral associada a oftalmoplegia internuclear unilateral em hemorragia mesencéfalo-pontina alta: relato de um caso / Combined lateral gaze palsy with unilateral internuclear ophthalmoplegia in high mesencephalo-pontine hemorrhage: report of a case

Relata-se um caso de hemorragia mesencéfalo-pontina alta direita, com oftalmoplegia extrínseca, permanecendo apenas a convergência bilateral, a abduçäo voluntária e automático-reflexa do olho esquerdo, e a aduçäo deste olho na pesquisa dos reflexos vestíbulo-oculares ("one-and-a-half syndrome") Ainda, havia dissociaçäo voluntária-automático da motricidade das pálpebras e dos movimentos conjugados verticais e, também, hemiplegia sensitivo-motora à esquerda e asterixis

Observaçöes sobre distúrbios dos movimentos oculares conjugados horizontais: as dissociaçöes voluntário-automático-reflexas / Conjugate horizontal eye movements disorders: the voluntary-automatic-reflexes dissociations

Estudam-se as dissociaçöes da motricidade ocular voluntária, automática e reflexa, segundo o modelo de Hughlings Jackson, baseados em dois casos com lesöes pontinas medianas, um caso com lesäo mesencéfalo-pontina alta e um caso com lesäo de gânglios da base e atrofia cortical (doença de Wilson). Também revisam sumariamente a interaçäo destes sistemas e as vias anatômicas envolvidas

Asterixis unilateral em hemorragia mesencefálica: estudo a propósito do relato de um caso / Unilateral asterixis in midbrain hemorrhage: study apropos of a case report

Relatam-se um caso de hemorragia no tegmento e teto mesencefálico e 1/4 superior da ponte direita apresentando-se com oftalmoplegia extrínseca completa à direita e parcial à esquerda, hemiparesia e, após, asterixis à esquerda, que perdurou por quatro semanas

Asterixis unilateral em hemorragia mesencefalica: estudo a proposito do relato de um caso

Os autores relatam um caso de hemorragia no tegmento e teto mesencefalico e 1/4 superior a da ponte direita apresentando-se com oftalmoplegia extrinseca completa a direita e parcial a esquerda, hemiparesia e, apos, asterixis a esquerda, que perdurou por quatro semanas.

Observacoes sobre disturbios dos movimentos oculares conjugados horizontais : as dissociacoes voluntario-automatico-reflexas

Os autores estudam as dissociacoes da motricidade ocular voluntaria, automatica e reflexa, segundo o modelo de Hughlins Jackson, baseados em dois casos em lesoes pontinas medianas, um caso com lesao mesencefalo-pontina alta e um caso com lesao de ganglios da base e atrofia cortical (doenca de Wilson). Tambem revisao sumariamente a interacao destes sistemas a as vias anatomicas envolvidas.