The periosteal-cutaneous chimeric medial femoral condyle free flap for subtotal ear reconstruction: A case report

When costal graft is contraindicated or refused by the patient, autologous total/subtotal auricular reconstruction represent a real challenge as limited surgical options has been described. Aim of present report is to offer a novel possible autologous reconstruction of the ear frame using a chimeric free medial femoral condyle (MFC) flap. We present a case of a 29 years old patient who had total loss of the upper 2/3 of the right ear after bombing in Somalia and secondary infected condritis (considered a relative contraindication for costal cartilage graft). The MFC flap was harvested with a chimeric skin paddle (7 × 5 cm), a thin sheet of femoral cortex (6.5 × 8 cm) was used as basal ear frame, while part of the contralateral concha was trimmed as support for the helix, with the periosteal component of the flap wrapping around the whole framework. The chimeric skin paddle assured the retroauricular skin coverage, while the anterior part of the construct was covered by a thinned dermal flap. Postoperative course was uneventful. A defatting procedure of the posterior skin paddle was performed at 2 months post-op. At 6 months post-op, the patient was satisfied with the result, could wear glasses and was socially integrated. This new application of the free chimeric MFC flap, despite being not the primary choice for ear reconstruction, guaranteed satisfactory results in terms of ear shape and infection prevention and may be considered when ordinary cartilage rib reconstruction is refused, contraindicated, or failed.     

Effect of the phosphogypsum amendment of saline and agricultural soils on growth,productivity and antioxidant enzyme activities of tomato (<Emphasis Type="BoldItalic">Solanum lycopersicum</Emphasis> L.)

The objective of this study was to investigate the effects of phosphogypsum (PG) amendment on the physiochemical proprieties of saline and agricultural soils along with the growth, productivity and antioxidant enzyme activities of tomato plants ( Solanum lycopersicum L.) grown on the amended soils under controlled conditions. Obtained results showed that the amendment of saline soil (H) by PG induced a decrease in pH as well as in electrical conductivity. However, for the non saline soil (MC), there was a decrease in pH associated with an increase in electrical conductivity. For both soils, PG amendment led to an increase in Calcium (Ca) and sodium (Na), and a decrease in potassium (K) in plant tissues. Cadmium (Cd), Zinc (Zn) and Chromium (Cr) contents in different parts of plants increased in proportion with PG concentration in the soils. Apart from Cd, all the analyzed metals in tomato fruit were found to be below the recommended maximum allowable concentration (MAC). Our results showed that PG application, at doses not exceeding 20%, seems to be beneficial for growth, photosynthetic activity and productivity of tomato plants as well as in decreasing salinity of saline soils. In these conditions, the use of PG could be a promising project for the rehabilitation of marginalized and saline ecosystems with either ornamental or non-fruit species. For both soils, a significant accumulation of MDA in shoots was detected, reflecting cell membrane damage especially when the PG amendment reached 20%. Beyond 20 and 40% PG, tomato plants developed an enzymatic antioxidant defense system in response to salinity and heavy metal stress. However, at 80% PG, enzymes activities were significantly inhibited.     

ℋ︁2 suboptimal estimation and control for nonnegative dynamical systems

Linear matrix inequalities (LMIs) provide a powerful design framework for linear control problems. In this paper, we use LMIs to develop ??₂ (sub)optimal estimators and controllers for nonnegative dynamical systems. Specifically, we formulate a series of generalized eigenvalue problems subject to a set of LMI constraints for designing ??₂ suboptimal estimators, static controllers, and dynamic controllers for nonnegative dynamical systems. The resulting ??₂ suboptimal controllers guarantee that the closed‐loop plant system states remain in the nonnegative orthant of the state space. Finally, a numerical example is provided to demonstrate the efficacy of the proposed approach. Copyright © 2008 John Wiley & Sons, Ltd.     

IL-9 induces differentiation of TH17 cells and enhances function of FoxP3+ natural regulatory T cells

The development of T helper (T_H)17 and regulatory T (T_reg) cells is reciprocally regulated by cytokines. Transforming growth factor (TGF)-β alone induces FoxP3⁺ T_reg cells, but together with IL-6 or IL-21 induces T_H17 cells. Here we demonstrate that IL-9 is a key molecule that affects differentiation of T_H17 cells and T_reg function. IL-9 predominantly produced by T_H17 cells, synergizes with TGF-β1 to differentiate naïve CD4⁺ T cells into T_H17 cells, while IL-9 secretion by T_H17 cells is regulated by IL-23. Interestingly, IL-9 enhances the suppressive functions of FoxP3⁺ CD4⁺ T_reg cells in vitro, and absence of IL-9 signaling weakens the suppressive activity of nT_regs in vivo, leading to an increase in effector cells and worsening of experimental autoimmune encephalomyelitis. The mechanism of IL-9 effects on T_H17 and T_regs is through activation of STAT3 and STAT5 signaling. Our findings highlight a role of IL-9 as a regulator of pathogenic versus protective mechanisms of immune responses.