Adhesion and proliferation of skeletal muscle cells on single layer poly(lactic acid) ultra-thin films

An increasing interest in bio-hybrid systems and cell-material interactions is evident in the last years. This leads towards the development of new nano-structured devices and the assessment of their biocompatibility. In the present study, the development of free-standing single layer poly(lactic acid) (PLA) ultra-thin films is described, together with the analysis of topography and roughness properties. The biocompatibility of the PLA films has been tested in vitro, by seeding C2C12 skeletal muscle cells, and thus assessing cells shape, density and viability after 24, 48 and 72 h. The results show that free-standing flexible PLA nanofilms represent a good matrix for C2C12 cells adhesion, spreading and proliferation. Early differentiation into myotubes is also allowed. The biocompatibility of the novel ultra-thin films as substrates for cell growth promotes their application in the fields of regenerative medicine, muscle tissue engineering, drug delivery, and-in general-in the field of bio-hybrid devices

Seismicity of the incoming plate and forearc near the Mariana Trench recorded by ocean bottom seismographs

Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 21(4), (2020): e2020GC008953, doi:10.1029/2020GC008953.Earthquakes near oceanic trenches are important for studying incoming plate bending and updip thrust zone seismogenesis, yet are poorly constrained using seismographs on land. We use an ocean bottom seismograph (OBS) deployment spanning both the incoming Pacific Plate and the forearc to study seismicity near the Mariana Trench. The yearlong deployment in 2012–2013 consisted of 20 broadband OBSs and 5 suspended hydrophones, with an additional 59 short period OBSs and hydrophones recording for 1 month. We locate 1,692 earthquakes using a nonlinear method with a 3D velocity model constructed from active source profiles and surface wave tomography results. Events occurring seaward of the trench occur to depths of ~35 km below the seafloor, and focal mechanisms of the larger events indicate normal faulting corresponding to plate bending. Significant seismicity emerges about 70 km seaward from the trench, and the seismicity rate increases continuously towards the trench, indicating that the largest bending deformation occurs near the trench axis. These plate‐bending earthquakes occur along faults that facilitate the hydration of the subducting plate, and the lateral and depth distribution of earthquakes is consistent with low‐velocity regions imaged in previous studies. The forearc is marked by a heterogeneous distribution of low magnitude (<5 Mw) thrust zone seismicity, possibly due to the rough incoming plate topography and/or serpentinization of the forearc. A sequence of thrust earthquakes occurs at depths ~10 km below seafloor and within 20 km of the trench axis, demonstrating that the megathrust is seismically active nearly to the trench.We thank the captains, crew, and science teams on the R/V Thompson, Langseth and Melville, Dr. Patrick Shore for providing data management and technical support, and Ivan Komarov and Zhengyang Zhou for assistance with data analysis. We thank Ingo Grevemeyer and an anonymous reviewer for their comments to improve the manuscript. Instrumentation and technical support was provided by the PASSCAL program of the Incorporated Research Institutions in Seismology (IRIS) and the Woods Hole, Lamont‐Doherty, and Scripps facilities of the Ocean Bottom Seismograph Instrumentation Pool (OBSIP). Funding was provided by the MARGINS/GeoPRISMS program through NSF grant OCE‐0841074 (D.A.W.) and the Spencer T. and Ann W. Olin Fellowship program at Washington University in Saint Louis. Raw seismic data used in this study are available through the Data Management Center of the Incorporated Research Institutions for Seismology (http://www.iris.edu/dms/nodes/dmc) under network IDs XF and MI.2020-10-0

Kinematics and Laxity of the Ankle Joint in Anatomic and Nonanatomic Anterior Talofibular Ligament Repair: A Biomechanical Cadaveric Study

足関節前距腓靭帯修復術における修復位置の違いが足関節のキネマティクスと制動性に及ぼす影響を検討した．解剖学的修復ではキネマティクス及び制動性は正常と差を認めなかった．非解剖学的修復ではキネマティクスは背屈時に内がえし方向，中間位で内旋方向への有意な変位を認め，制動性は底屈位で内旋の変位が有意に大きくなり，正常とは異なるキネマティクス及び制動性を示した

The Endogenous Th17 Response in NO<inf>2</inf>-Promoted Allergic Airway Disease Is Dispensable for Airway Hyperresponsiveness and Distinct from Th17 Adoptive Transfer

Severe, glucocorticoid-resistant asthma comprises 5-7% of patients with asthma. IL-17 is a biomarker of severe asthma, and the adoptive transfer of Th17 cells in mice is sufficient to induce glucocorticoid-resistant allergic airway disease. Nitrogen dioxide (NO2) is an environmental toxin that correlates with asthma severity, exacerbation, and risk of adverse outcomes. Mice that are allergically sensitized to the antigen ovalbumin by exposure to NO2 exhibit a mixed Th2/Th17 adaptive immune response and eosinophil and neutrophil recruitment to the airway following antigen challenge, a phenotype reminiscent of severe clinical asthma. Because IL-1 receptor (IL-1R) signaling is critical in the generation of the Th17 response in vivo, we hypothesized that the IL-1R/Th17 axis contributes to pulmonary inflammation and airway hyperresponsiveness (AHR) in NO2-promoted allergic airway disease and manifests in glucocorticoid-resistant cytokine production. IL-17A neutralization at the time of antigen challenge or genetic deficiency in IL-1R resulted in decreased neutrophil recruitment to the airway following antigen challenge but did not protect against the development of AHR. Instead, IL-1R-/- mice developed exacerbated AHR compared to WT mice. Lung cells from NO2-allergically inflamed mice that were treated in vitro with dexamethasone (Dex) during antigen restimulation exhibited reduced Th17 cytokine production, whereas Th17 cytokine production by lung cells from recipient mice of in vitro Th17-polarized OTII T-cells was resistant to Dex. These results demonstrate that the IL-1R/Th17 axis does not contribute to AHR development in NO2-promoted allergic airway disease, that Th17 adoptive transfer does not necessarily reflect an endogenously-generated Th17 response, and that functions of Th17 responses are contingent on the experimental conditions in which they are generated. © 2013 Martin et al

0-6839: Designing Pavements to Support the Heavy Loads in the Energy Development Areas

0-6839In recent years, rapid energy development in Texas has caused significant damage to many farm-to-market (FM) roads, which traditionally have a thin asphalt surface layer plus a stabilized base directly over the subgrade. These roadways were often rehabilitated with full-depth reclamation (FDR), and often 2 to 3 percent cement was added to the pulverized existing materials. These roadways performed well under normal traffic loads but failed dramatically under the energy-sector truck loads. Figure 1 shows the damaged FM roads. The impact of overloading traffic on pavement damage is not only limited to FM roads; it also has significant influence on the pavement life of state highways and even interstate highways. There is an urgent need to repair many of these badly damaged roadways in all energy development areas

Failure to prescribe pneumocystis prophylaxis is associated with increased mortality, even in the cART era: results from the Treat Asia HIV observational database

<p>Abstract</p> <p>Background</p> <p>Pneumocystis jiroveci pneumonia (PCP) prophylaxis is recommended for patients with CD4 counts of less than 200 cells/mm³. This study examines the proportion of patients in the TREAT Asia HIV Observational Database (TAHOD) receiving PCP prophylaxis, and its effect on PCP and mortality.</p> <p>Methods</p> <p>TAHOD patients with prospective follow up had data extracted for prophylaxis using co-trimoxazole, dapsone or pentamidine. The proportion of patients on prophylaxis was calculated for each calendar year since 2003 among patients with CD4 counts of less than 200 cells/mm³. The effect of prophylaxis on PCP and survival were assessed using random-effect Poisson regression models.</p> <p>Results</p> <p>There were a total of 4050 patients on prospective follow up, and 90% of them were receiving combination antiretroviral therapy. Of those with CD4 counts of less than 200 cells/mm³, 58% to 72% in any given year received PCP prophylaxis, predominantly co-trimoxazole. During follow up, 62 patients developed PCP (0.5 per 100 person-years) and 169 died from all causes (1.36/100 person-years). After stratifying by site and adjusting for age, CD4 count, CDC stage and antiretroviral treatment, those without prophylaxis had no higher risk of PCP, but had a significantly higher risk of death (incident rate ratio 10.8, p < 0.001). PCP prophylaxis had greatest absolute benefit in patients with CD4 counts of less than 50 cells/mm³, lowering mortality rates from 33.5 to 6.3 per 100 person-years.</p> <p>Conclusions</p> <p>Approximately two-thirds of TAHOD patients with CD4 counts of less than 200 cells/mm³received PCP prophylaxis. Patients without prophylaxis had significantly higher mortality, even in the era of combination ART. Although PCP may be under-diagnosed, these data suggest that prophylaxis is associated with important survival benefits.</p