Dynamic Reconstruction of Facial Paralysis in Craniofacial Microsomia

BACKGROUND: Craniofacial microsomia is associated with maxillomandibular hypoplasia, microtia, soft-tissue deficiency, and variable severity of cranial nerve dysfunction, most often of the facial nerve. This study evaluated the incidence of facial paralysis in patients with craniofacial microsomia and outcomes after free functioning muscle transfer for dynamic smile reconstruction. METHODS: A single-center, retrospective, cross-sectional study was performed from 1985 to 2018 to identify pediatric patients with craniofacial microsomia and severe facial nerve dysfunction who underwent dynamic smile reconstruction with free functioning muscle transfer. Preoperative and postoperative facial symmetry and oral commissure excursion during maximal smile were measured using photogrammetric facial analysis software. RESULTS: This study included 186 patients with craniofacial microsomia; 41 patients (21 male patients, 20 female patients) had documented facial nerve dysfunction (22 percent) affecting all branches (51 percent) or the mandibular branch only (24 percent). Patients with severe facial paralysis (n = 8) underwent smile reconstruction with a free functioning muscle transfer neurotized either with a cross-face nerve graft (n = 7) or with the ipsilateral motor nerve to masseter (n =1). All patients achieved volitional muscle contraction with improvement in lip symmetry and oral commissure excursion (median, 8 mm; interquartile range, 3 to 10 mm). The timing of orthognathic surgery and facial paralysis reconstruction was an important consideration in optimizing patient outcomes. CONCLUSIONS: The authors' institution's incidence of facial nerve dysfunction in children with craniofacial microsomia is 22 percent. Free functioning muscle transfer is a reliable option for smile reconstruction in children with craniofacial microsomia. To optimize outcomes, a novel treatment algorithm is proposed for craniofacial microsomia patients likely to require both orthognathic surgery and facial paralysis reconstruction

DMSO and Betaine Greatly Improve Amplification of GC-Rich Constructs in De Novo Synthesis

In Synthetic Biology, de novo synthesis of GC-rich constructs poses a major challenge because of secondary structure formation and mispriming. While there are many web-based tools for codon optimizing difficult regions, no method currently exists that allows for potentially phenotypically important sequence conservation. Therefore, to overcome these limitations in researching GC-rich genes and their non-coding elements, we explored the use of DMSO and betaine in two conventional methods of assembly and amplification. For this study, we compared the polymerase (PCA) and ligase-based (LCR) methods for construction of two GC-rich gene fragments implicated in tumorigenesis, IGF2R and BRAF. Though we found no benefit in employing either DMSO or betaine during the assembly steps, both additives greatly improved target product specificity and yield during PCR amplification. Of the methods tested, LCR assembly proved far superior to PCA, generating a much more stable template to amplify from. We further report that DMSO and betaine are highly compatible with all other reaction components of gene synthesis and do not require any additional protocol modifications. Furthermore, we believe either additive will allow for the production of a wide variety of GC-rich gene constructs without the need for expensive and time-consuming sample extraction and purification prior to downstream application

Label-free protein detection based on the heat-transfer method-a case study with the peanut allergen Ara h 1 and aptamer-based synthetic receptors

© 2015 American Chemical Society. Aptamers are an emerging class of molecules that, because of the development of the systematic evolution of ligands by exponential enrichment (SELEX) process, can recognize virtually every target ranging from ions, to proteins, and even whole cells. Although there are many techniques capable of detecting template molecules with aptamer-based systems with high specificity and selectivity, they lack the possibility of integrating them into a compact and portable biosensor setup. Therefore, we will present the heat-transfer method (HTM) as an interesting alternative because this offers detection in a fast and low-cost manner and has the possibility of performing experiments with a fully integrated device. This concept has been demonstrated for a variety of applications including DNA mutation analysis and screening of cancer cells. To the best our knowledge, this is the first report on HTM-based detection of proteins, in this case specifically with aptamer-type receptors. For proof-of-principle purposes, measurements will be performed with the peanut allergen Ara h 1 and results indicate detection limits in the lower nanomolar regime in buffer liquid. As a first proof-of-application, spiked Ara h 1 solutions will be studied in a food matrix of dissolved peanut butter. Reference experiments with the quartz-crystal microbalance will allow for an estimate of the areal density of aptamer molecules on the sensor-chip surface