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Objectives: Among patients over 75 years, little is known about functional decline due to COVID-19. The aim of this study was to explore this functional decline, compare to other infectious pneumonia. Design and Setting: This case-control study included all COVID-19 patients hospitalized from March to December 2020 in Acute Geriatric Ward in Nantes University Hospital matched 1/1 with patients with pneumonia hospitalized in geriatric department between March 2017 and March 2019 (controls) on sex, age. Functional decline was assessed at 3 month follow up as it is routinely done after hospitalization in geriatric ward. We performed multivariable analyses to compare clinical outcomes between patients with COVID-19 vs controls. Results: 132 pairs were matched on age (mean: 87 y-o), and sex (61% of women). In multivariable logistic regression analysis, there were no statistical significant association between COVID-19 infection and functional decline (OR=0.89 p=0.72). A statistical significant association was found between functional decline and Charlson comorbidity index (OR=1.17, p=0.039); prior fall (OR=2.08, p=0.012); malnutrition (OR=1.97, p=0.018); length of hospital stay (OR=1.05, p=0.002) and preadmission ADL(OR=1.25, p=0.049). Conclusion: COVID-19 does not seem to be responsible for a more frequent or severe functional decline than other infectious pneumonia in older and comorbid population after 3 month follow up. In this population, pneumonia is associated with functional decline in almost 1 in 2 cases. The individual preadmission frailty seems to be a more important predictor of functional decline, encouraging multidimensional care management for this population. [ABSTRACT FROM AUTHOR]

A nonlinear extended finite element (XFEM) modeling framework under a stochastic cohesive zone is presented for realistic prediction of delamination in polyphenylene sulfide (PPS)/glass composites in mode I of fracture. The cohesive zone model adopts damage evolution of the material based on a bilinear traction-separation law, the critical energy release rate and the J-integral method to formulate the delamination interface under stochastic fracture properties. To demonstrate the application of the approach, numerical predictions are compared to experimental data using Double Cantilever Beam (DCB) tests. In particular, it is shown how the XFEM model can be used to capture test non-repeatability due to uncertain fracture properties, which is often the case during the characterization of composites using standard fracture tests. [ABSTRACT FROM AUTHOR]

Biomedical thermal spray coatings produced via high-velocity oxy-fuel (HVOF) from nanostructured titania (n-TiO2) and 10 wt.% hydroxyapatite (HA) (n-TiO2-10wt.%HA) powders have been engineered as possible future alternatives to HA coatings deposited via air plasma spray (APS). This approach was chosen due to (i) the stability of TiO2 in the human body (i.e., no dissolution) and (ii) bond strength values on Ti-6Al-4V substrates more than two times higher than those of APS HA coatings. To explore the bioperformance of these novel materials and coatings, human mesenchymal stem cells (hMSCs) were cultured from 1 to 21 days on the surface of HVOF-sprayed n-TiO2 and n-TiO2-10 wt.%HA coatings. APS HA coatings and uncoated Ti-6Al-4V substrates were employed as controls. The profiles of the hMSCs were evaluated for (i) cellular proliferation, (ii) biochemical analysis of alkaline phosphatase (ALP) activity, (iii) cytoskeleton organization (fluorescent/confocal microscopy), and (iv) cell/substrate interaction via scanning electron microscopy (SEM). The biochemical analysis indicated that the hMSCs cultured on n-TiO2-10 wt.%HA coatings exhibited superior levels of bioactivity than hMSCs cultured on APS HA and pure n-TiO2 coatings. The cytoskeleton organization demonstrated a higher degree of cellular proliferation on the HVOF-sprayed n-TiO2-10wt.%HA coatings when compared to the control coatings. These results are considered promising for engineering improved performance in the next generation of thermally sprayed biomedical coatings. [ABSTRACT FROM AUTHOR]

It is well known that interstitials affect the mechanical properties of titanium and titanium alloys. Their effects on the fatigue properties of titanium foams have not, however, been documented in the literature. This paper presents the effect of the oxygen content on the static and dynamic compression properties of titanium foams. Increasing the oxygen content from 0.24 to 0.51 wt% O in solution significantly increases the yield strength and reduces the ductility of the foams. However, the fatigue limit is not significantly affected by the oxygen content and falls within the 92 MPa ± 12 MPa range for all specimens investigated in this study. During cyclic loading, deformation is initially coming from cumulative creep followed by the formation of microcracks. The coalescence of these microcracks is responsible for the rupture of the specimens. Fracture surfaces of the specimens having lower oxygen content show a more ductile aspect than the specimens having higher oxygen content. [ABSTRACT FROM AUTHOR]

The aging baby boomer population coupled with an increase in life expectancy is leading to a rising number of active elderly persons in occidental countries. As a result, the orthopedic implant industry is facing numerous challenges such as the need to extend implant life, reduce the incidence of revision surgery, and improve implant performance. This paper reports results of an investigation on the bioperformance of newly developed coating-substrate systems. Hydroxyapatite (HA) and nano-titania (nano-TiO2) coatings were produced on Ti-6Al-4V and fiber reinforced polymer composite substrates. In vitro studies were conducted to determine the capacity of bioactive coatings developed to sustain osteoblast cells (fetal rat calvaria) adherence, growth, and differentiation. As revealed by scanning electron microscopy (SEM) observations and alkaline phosphatase activity, cell adhesion and proliferation demonstrated that HA coatings over a polymer composite are at least as good as HA coatings made over Ti-6Al-4V substrate in terms of osteoblast cell activity. Nano-TiO2 coatings produced by high-velocity oxyfuel (HVOF) spraying led to different results. For short-term cell culture (4.5 and 24 h), the osteoblasts appeared more flattened when grown on nano-TiO2 than on HA. The surface cell coverage after seven days of incubation was also more complete on nano-TiO2 than HA. Preliminary results indicate that osteoblast activity after 15 days of incubation on nano-TiO2 is equivalent to or greater than that observed on HA. [ABSTRACT FROM AUTHOR]

In vivo gene electrotransfer (ET) is a simple method of gene delivery in various tissues relying on the injection of plasmid DNA followed by application of electric pulses. Noninvasive tools are needed to evaluate the ET efficiency and the resulting tissue damages. In this study, we performed ET of rat tibialis muscle after injection of either a plasmid coding for luciferase or a contrast agent (CA) detected by using magnetic resonance imaging (MRI). Plasmid expression and CA intracellular trapped quantity were compared throughout the electric field intensity range 0–300 V/cm. Although the CA trapped quantity reflects only the electropermeabilization step, both measurements were correlated. MRI measurements gave easy access to tridimensional visualization of the labelled zones where the CA has been injected and the applied electric field had a value allowing permeabilization. We also performed MRI measurements of the water transverse relaxation time T2 as an indicator of tissue modification, and tested whether another CA specific for necrosis could be used to detect muscle necrosis at high electric field intensity. In conclusion, MRI measurements may bring multiparametric information upon the efficiency and tissue toxicity of an ET protocol by using a simple and safe CA.Gene Therapy (2005) 12, 1434–1443. doi:10.1038/sj.gt.3302541; published online 5 May 2005 [ABSTRACT FROM AUTHOR]

Gene electrotranfer is an attractive physical method to deliver genes to target tissues. The aim of this study was to evaluate in vivo gene electrotransfer into spleen, one of the most important lymphoid organ, in order to create a new tool to modulate the immuno-inflammatory system. C57BI/6 mice were submitted either to intramuscular electrotransfer (IME) as a reference method or to intrasplenic (ISE) gene electrotransfer. In the naked injected plasmids, the CMV promoter controlled the expression of luciferase, secreted alkaline phosphatase, EGFP, or IFNγ. The ISE optimal electrotransfer conditions were first determined and ISE was found to be an efficient gene transfer method, which can be used to express secreted or intracellular proteins transiently. Although transfected cells were still present in the spleen 30 days after ISE, transfected spleen cells could recirculate since they were detected in extrasplenic locations. Using a Tlymphocyte-specific promoter controlling the expression of EGFP, splenic T cells could be targeted. Finally, it appeared that ISE procedure does not impair by itself the immune response and does not result in a significant production of antibodies directed to the transgenic proteins in C57BI/6 mice. This strategy constitutes a new method to manipulate the immune response that can be used in various experimental designs. [ABSTRACT FROM AUTHOR]

We present a near-infrared Kn-band photometric study of edge-on galaxies with a box/peanut-shaped ‘bulge’. The morphology of the galaxies is analysed using unsharp masking and fits to the vertical surface brightness profiles, and the results are compared to N-body simulations and orbital calculations of barred galaxies. Both theoretical approaches reproduce the main structures observed. [ABSTRACT FROM AUTHOR]

Copyright of Rheologica Acta is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rheologica Acta is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A prospective study of abdominal and chest films of 212 babies without symptoms of intra-abdominal disease, aged 1 day-12 weeks, showed that the bubbly "fecal pattern" normally seen in older children is rare in young premature babies in the first two weeks of life. When it is seen, it may represent intramural air bubbles and signal the presence of necrotizing enterocolitis. [ABSTRACT FROM AUTHOR]

In three awake dogs in a hypobaric chamber at 140 m and at 3550 m, resting ventilation, pulmonary gas exchanges, respiratory gases and pH of the arterial blood, acid-base status in the cerebrospinal fluid (csf), and ventilatory responses to transient O-inhalation were studied before ( intact) and after chronic bilateral carotid body denervation ( cbd). 1.The hypoxic chemoreflex drive of ventilation was reduced by about half in cbd dogs. 2. At low altitude, sino-carotid body denervation resulted in hypoventilation and respiratory acidosis in the arterial blood and csf. 3. At high altitude, initial hypoxic hyperventilation, and the related alkalosis in blood and csf, occurred within 30 min in intact dogs, but was not observed in cbd ones. 4. Further increase in ventilation was achieved upon 3 hrs of altitude exposure in intact animals, while a delayed hyperventilation occurred after 24 hrs in cbd ones. 5. Neither in intact nor in cbd dogs, the ventilatory changes at altitude were related to the changes in csf pH. It is concluded that the rate of ventilatory acclimatization to altitude is dependent upon the strength of the arterial chemoreceptor drive. Integrity of this chemoreflex drive of breathing is essential in determining the eupneic level of ventilation and normal acid-base status of the blood and csf at low altitude and at high altitude. [ABSTRACT FROM AUTHOR]

The article discusses the arterial wall mechanical behavior. Arteriosclerosis is caused by the formation of atheromateous plate constituted by proliferation and deposits of cholesterol in lipidic scratches involving thickening of the intima, which leads to a stenosis. Clinical complications are also related to the possibility of calcification eventually leading to a rupture, cholesterol embolus and ulceration of the thrombotic plate. Failure to obtain acceptable compliance may result in improper anastomosis and mechanical mismatch, which eventually lead to the failure of the implant .

The interactions between LPS-induced bronchial hyper-reactivity (BHR) and lung inflammation (LI) were investigated. LPS-induced LI was assessed with the augmented alveolo-capillary permeability (ACP) and with the increased migration of neutrophils into the broncho-alveolar lavage fluid. BHR was defined as the increase in the response to a standard dose of serotonin. Mepyramine and the PAF antagonist WEB 2170 blocked LPS-induced increase of ACP, whereas aspirin was inactive. By contrast, neither LPS-induced neutrophil attraction to airways, nor LPS-induced HBR were inhibited by these agents. Our results indicate that LPS-induced edema and BHR are dissociated. [ABSTRACT FROM AUTHOR]