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61.
In vitro development of engineered muscle using a scaffold based on the pressure‐activated microsyringe (PAM) technique
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Daniele Cei Adriana Malena Carmelo de Maria Emanuele Loro Federica Sandri Giulia del Moro Sara Bettio Lodovica Vergani Giovanni Vozzi 《Journal of tissue engineering and regenerative medicine》2017,11(1):138-152
The development of new human skeletal muscle tissue is an alternative approach to the replacement of tissue after severe damage, for example in the case of traumatic injury, where surgical reconstruction is often needed following major loss of natural tissue. Treatment to date has involved the transfer of muscle tissue from other sites, resulting in a functional loss and volume deficiency of donor sites. Approaches that seek to eliminate these problems include the relatively new solution of skeletal muscle engineering. Here there are two main components to consider: (a) the cells with their regenerative potential; and (b) the polymeric structure onto which cells are seeded and where they must perform their activities. In this paper we describe well‐defined two‐ and three‐dimensional polymeric structures able to drive the myoblast process of adhesion, proliferation and differentiation. We examine a series of polymers and protein adhesions with which to functionalize the structures, and cell‐seeding methods, with a view to defining the optimal protocol for engineering skeletal muscle tissue. All polymer samples were tested for their mechanical and biological properties, to support the validity of our results in the real context of muscle tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
62.
Prevalence and Factors Associated with Subclinical Left Ventricular Systolic Dysfunction Evaluated by Mid‐Wall Mechanics in Rheumatoid Arthritis
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63.
Several hundreds of studies recently investigated mean platelet volume (MPV) as measured by electronic cell counters in a wide variety of acquired diseases, and most of them found that platelet size was significantly increased with respect to healthy subjects. On this basis, it has been suggested that MPV can be used for diagnostic purposes. Moreover, investigation of subjects with arterial thrombosis not only revealed that their platelets were larger than those of controls, but also found that a high MPV predicted poor prognosis. Despite the large amount of available data, the pathogenesis of increased platelet size in these conditions is unclear. In particular, we do not know whether the increased platelet size is the cause or the consequence of thrombosis. Differences in MPV between patients and controls are usually very small and they reach the statistical significance because of the large number of investigated patients and the standardized methodology for MPV measurement. In real life, the wide variability of MPV possibly due to platelet count, sex, age, and ethnicity, as well as the very poor standardization of the methodologies used for MPV measurement, makes it impossible to decide whether an individual patient has normal or instead slightly increased MPV. So, MPV has presently no role in making diagnosis and defining prognosis in any acquired illness. 相似文献
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Satoshi Uchiyama Federica Andreoni Claudia Zürcher Katrin Schilcher Miriam Ender Jerzy Madon Ulrich Matt Partho Ghosh Victor Nizet Reto A. Schuepbach Annelies S. Zinkernagel 《Journal of molecular medicine (Berlin, Germany)》2013,91(7):861-869
Group A Streptococcus (GAS) is a human pathogen causing a wide range of mild to severe and life-threatening diseases. The GAS M1 protein is a major virulence factor promoting GAS invasiveness and resistance to host innate immune clearance. M1 displays an irregular coiled-coil structure, including the B-repeats that bind fibrinogen. Previously, we found that B-repeat stabilisation generates an idealised version of M1 (M1*) characterised by decreased fibrinogen binding in vitro. To extend these findings based on a soluble truncated version of M1, we now studied the importance of the B-repeat coiled-coil irregularities in full length M1 and M1* expressed in live GAS and tested whether the modulation of M1–fibrinogen interactions would open up novel therapeutic approaches. We found that altering either the M1 structure on the GAS cell surface or removing its target host protein fibrinogen blunted GAS virulence. GAS expressing M1* showed an impaired ability to adhere to and to invade human endothelial cells, was more readily killed by whole blood or neutrophils and most importantly was less virulent in a murine necrotising fasciitis model. M1-mediated virulence of wild-type GAS was strictly dependent on the presence and concentration of fibrinogen complementing our finding that M1–fibrinogen interactions are crucial for GAS virulence. Consistently blocking M1–fibrinogen interactions by fragment D reduced GAS virulence in vitro and in vivo. This supports our conclusion that M1–fibrinogen interactions are crucial for GAS virulence and that interference may open up novel complementary treatment options for GAS infections caused by the leading invasive GAS strain M1. 相似文献
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Sagüés María Federica Fusé Luis Alberto Iglesias Lucía Emilia Moreno Fabiana Carina Saumell Carlos Alfredo 《Parasitology research》2013,112(3):1047-1051
The large-scale production of nematophagous fungi as agents of biological control is one of the main challenges to be commercially used. In order to improve growth of microorganism in a culture medium, the addition of growth inducer is common. At the moment, the action of their addition in the mycelia growth and sporulation rate of nematophagous fungi is not known. The purpose of this trial was to evaluate the sporulation rate of Duddingtonia flagrans by adding two growth inducers, meso-inositol and Tween 80, both at 0.5 % in a traditional culture medium Sabouraud glucose agar (SGA) and also in a traditional culture medium enriched with wheat flour and milk powder. From a traditional sterile culture of D. flagrans, four groups were made: SGA; Sabouraud glucose agar–meso-inositol 0.5 %; Sabouraud glucose agar–Tween 80 0.5 %; and Sabouraud glucose agar-enriched (SGA-E). These media were placed at a constant temperature of 27 °C for 4 weeks. Following this, chlamydospores were gently rinsed off with sterile water and counted using a Neubauer haematocytometer to estimate the number of chlamydospores per millilitre of water. The addition of meso-inositol 0.5 % to SGA promoted a significant increase (p?<?0.05) in chlamydospore production obtaining an average of 51,715,000 chlamydospores per Petri dish. The highest chlamydospore concentration was observed in the SGA-E in comparison with SGA (p?<?0.01) obtaining an average of 208,760,000 chlamydospores. The aim of this study was to obtain basic knowledge regarding the effect of enriched culture medium and growth-inducing meso-inositol and Tween 80 on mycelial growth and production of chlamydospores. 相似文献
69.
IJ Collins J Cairns G Jourdain F Fregonese M Nantarukchaikul N Lertpienthum P Wannarit P Attavinijtrakarn P Layangool S Le Coeur M Lallemant;for the Program for HIV Prevention Treatment 《AIDS (London, England)》2012,26(15):1943-1952
OBJECTIVE:: To assess hospitalization trends in HIV-infected children on antiretroviral therapy (ART) in Thailand, an important indicator of morbidity, ART effectiveness, and health service utilization. DESIGN:: Prospective observational cohort METHOD:: Children initiating ART in 1999-2009 were followed in 40 public hospitals. Hospitalization rate per 100 person-years were calculated from ART initiation to last follow-up/death. Costs to the healthcare provider were calculated using WHO inpatient estimates for Thailand. Zero-inflated Poisson models were used to examine risk factors for early (<12 months of ART) and late hospitalization (≥12 months) and frequency of admissions. RESULTS:: A total of 578 children initiated ART, median follow-up being 64 months [interquartile range (IQR) 43-82]; 211 (37%) children were hospitalized with 451 admissions. Hospitalization rates declined from 63 per 100 person-years at less than 6 months to approximately 10 per 100 person-years after 2 years of ART, and costs fell from $35 per patient-month to under $5, respectively. Age less than 2 years, US Centers of Disease Control and Prevention stage B/C, and stunting at ART initiation were associated with early hospitalization. Among those hospitalized, baseline CD4 cell percentage less than 5%, wasting, initiation on dual therapy, late calendar year, and female sex were associated with higher incidence of early admissions (P?<0.02). There were no predictors of late hospitalization, although previous hospitalization in less than 12 months of ART was associated with three times higher incidence of late admissions (P?0.0001). CONCLUSION:: One in three children required hospitalization after ART. Admissions were highest in the first year of therapy and rapidly declined thereafter. Young age, advanced disease stage, and stunting at baseline were predictive of early hospitalization. Treatment initiation before disease progression would likely reduce hospitalization and alleviate demands on healthcare services. 相似文献
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