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Purpose: The vascularity, bone mineral density distribution, and histomorphometric data between the inbred, isogenic Lewis rat and the outbred, nonisogenic Sprague Dawley rat within mandibular distraction osteogenesis (MDO) were evaluated to allow future researchers to compare the results generated from these 2 animals. We hypothesized that little difference would be found between the 2 strains within these metrics.Materials and Methods: We implemented a comparative study between the Lewis and Sprague Dawley rat strains within MDO. The sample was composed of 17 male Lewis and 17 male Sprague Dawley rats that underwent surgical external fixation and distraction. The rats' hemimandibles were distracted to a total distance of 5.1 mm. After 28 days of consolidation, 9 rats from each group underwent bone mineral density distribution analysis. The remaining rats from each group were analyzed for the vascular and histologic metrics. Descriptive and bivariate statistics were computed, and the P value was set at .05.Results: We demonstrated successful MDO in all the rats, with no significant difference found in the histologic or bone mineral density distribution metrics. No significant differences were found in any of the vascular metrics, with the exception of vascular separation, which was not normalized to the mandibular volume (P = .048).Conclusions: The results of the present study have demonstrated that little dissimilarity exists between the isogenic Lewis and outbred Sprague Dawley models of MDO. Thus, researchers can confidently compare the gross results between the 2 strains, with consideration of the very small differences between the 2 models. For studies that require an isogenic strain, the Lewis rat is an apt surrogate for the Sprague Dawley strain. [ABSTRACT FROM AUTHOR]

Background Bony non-unions arising in the aftermath of collateral radiation injury are commonly managed with vascularized free tissue transfers. Unfortunately, these procedures are invasive and fraught with attendant morbidities. This study investigated a novel, alternative treatment paradigm utilizing adipose-derived stem cells (ASCs) combined with angiogenic deferoxamine (DFO) in the rat mandible. Methods Rats were exposed to a bioequivalent dose of radiation and mandibular osteotomy. Those exhibiting non-unions were subsequently treated with surgical debridement alone or debridement plus combination therapy. Radiographic and biomechanical outcomes were assessed after healing. Results Significant increases in biomechanical strength and radiographic metrics were observed in response to combination therapy ( p < .05). Importantly, combined therapy enabled a 65% reduction in persisting non-unions when compared to debridement alone. Conclusion We support the continued investigation of this promising combination therapy in its potential translation for the management of radiation-induced bony pathology. © 2015 Wiley Periodicals, Inc. Head Neck 38: E837-E843, 2016 [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to further define the impact of primary surgery in the management of oropharyngeal squamous cell carcinoma (SCC). Methods Two hundred ninety-six patients with oropharyngeal SCC treated with primary surgery were included. Multivariable analysis and recursive partitioning analysis (RPA) identified predictors of survival and gastrostomy tube presence. Results Multivariable analysis identified that HPV negativity ( p = .0002), presence of extranodal extension ( p = .0025), and advanced T classification ( p = .0081) were independent predictors of survival. For HPV-positive patients, surgical approach ( p = .0111) and margin status ( p = .0287) were significant predictors of survival. For HPV-negative patients, extranodal extension ( p = .0021) and advanced T classification ( p = .0342) were significant predictors of survival. Smoking status and advanced neck disease did not impact survival, and the addition of adjuvant chemotherapy did not confer survival benefit in HPV-positive or HPV-negative subgroups. Conclusion Independent predictors of survival are unique in patients with oropharyngeal SCC treated with primary surgery. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1794-E1802, 2016 [ABSTRACT FROM AUTHOR]

Intrinsically doped samples of YCuTe2 were prepared by solid state reaction of the elements. Based on the differential scanning calorimetry and the high temperature X-ray diffraction analyses, YCuTe2 exhibits a first order phase transition at ∼440 K from a low-temperature-phase crystallizing in the space group P3̅m1 to a high-temperature-phase in P3̅. Above the phase transition temperature, partially ordered Cu atoms become completely disordered in the crystal structure. Small increases to the Cu content are observed to favour the formation of the high temperature phase. We find no indication of superionic Cu ions as for binary copper chalcogenides (e.g., Cu2Se or Cu2Te). All investigated samples exhibit very low thermal conductivities (as low as ∼0.5 W m−1 K−1 at 800 K) due to highly disordered Cu atoms. Electronic structure calculations are employed to better understand the high thermoelectric efficiency for YCuTe2. The maximum thermoelectric figure of merit, zT, is measured to be ∼0.75 at 780 K for Y0.96Cu1.08Te2, which is promising for mid-temperature thermoelectric applications. [ABSTRACT FROM AUTHOR]

This study examined the microstructure evolution of sputtered Bi-Te films during post-annealing. Combining X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses, we unraveled the fundamental aspects of the materials process: The as-deposited film was not in the Bi2Te3-type phase but in a metastable phase based on a rock-salt structure. Annealing at an elevated temperature allowed the nucleation and growth of the stable phase from the film of the metastable phase in a typical manner of the heterogeneous phase transformation. In addition, the growth of the stable phase is found accountable for the remarkable improvements of the electrical and thermoelectric properties of the films observed after post-annealing. [ABSTRACT FROM AUTHOR]

Avian prolactin (PRL) secretion is regulated by vasoactive intestinal peptide (VIP) neurons residing in the infundibular nuclear complex (INF) of the hypothalamus. This VIPergic activity is modulated by stimulatory dopaminergic inputs. Dynorphin, serotonin (5-HT), dopamine (DA) and VIP all appear to stimulate PRL secretion along a hypothalamic pathway, expressing κ opioid, serotonergic, dopaminergic and VIPergic receptors in succession, with the VIPergic system as the final mediator. Electrical stimulation (ES) within the turkey hypothalamus at the level of the medial preoptic area (POA), the ventromedial hypothalamic nucleus (VMN), the INF or the median eminence (ME) results in the release of PRL. When the selective D[sub 1] DA receptor antagonist SCH-23390 HCl was infused intraventricularly at the rate of 10 nmol/min, ES in the POA or VMN was unable to increase PRL levels, while ES in the INF and ME did increase PRL to the same level as that of controls. These results were interpreted to suggest that the D[sub 1] DA receptors involved in PRL release lie caudally to the VMN and dorsally to the INF. Bilateral microinjections (50 ng) of the D[sub 1] DA receptor agonist SKF-38393 HCl into the POA or VMN failed to produce any increase in PRL, while similar microinjections in the INF increased PRL significantly within 15 min. Bilateral microinjections of the D[sub 1] DA antagonist (50 ng) into the INF blocked the rise in PRL associated with ES in the POA. Bilateral microinjections of a D[sub 2] DA antagonist (50 ng) into the INF failed to block PRL secretion induced by ES in the POA. Tract tracing, using double-label immunocytochemistry, revealed the presence of a monosynaptic dopaminergic pathway projecting from the POA to the INF. These data imply that the only hypothalamic D[sub 1] DA receptors involved in the regulation of avian PRL secretion are those residing within the INF in the same region as the VIP neurons known to be involved in PRL secretion.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Highly resistive grain boundaries significantly reduce the electrical conductivity that compromises the thermoelectric figure‐of‐merit zT in n‐type polycrystalline Mg3Sb2. In this work, discovered is a Mg deficiency near grain boundaries using atom‐probe tomography. Approximately 5 at% of Mg deficiency is observed uniformly in a 10 nm region along the grain boundary without any evidence of a stable secondary or impurity phase. The off‐stoichiometry can prevent n‐type dopants from providing electrons, lowering the local carrier concentration near the grain boundary and thus the local conductivity. This observation explains how nanometer scale compositional variations can dramatically determine thermoelectric zT, and provides concrete strategies to reduce grain‐boundary resistance and increase zT in Mg3Sb2‐based materials. [ABSTRACT FROM AUTHOR]

Simple Summary: Salivary duct carcinomas (SDC) can present with distinct immunologic profiles similar to breast cancer, such as androgen receptor (AR) and HER-2/Neu-positivity, raising the hypothesis that these tumors may respond to hormonal signaling. No consensus exists on how to best manage this entity. The data evaluating the use of targeted therapies, such as androgen deprivation therapy and HER-2 receptor inhibitors, in the front-line setting when treating curatively is limited. We studied patients with AR+ SDC, demonstrating high rates of control and survival using an aggressive approach to treatment. Immunoprofiles were highly variable, highlighting the potential for future treatment individualization. We hope that this may allow for personalization of treatment in the future, using molecular profiling to determine whether the addition of biological agents in the definitive setting against specific targets, such as AR and HER-2/Neu, will further improve outcomes for these patients. Background: Salivary duct carcinomas (SDC) are a rare and aggressive subtype of salivary gland neoplasm. They can present with distinct immunoprofiles, such as androgen receptor (AR) and HER-2/Neu-positivity. To date, no consensus exists on how to best manage this entity. Methods: All patients diagnosed with nonmetastatic AR+ SDC of the parotid from 2013 to 2019 treated with curative intent were included. Immunologic tumor profiling was conducted using 24 distinct markers. Kaplan–Meier analyses were used to estimate locoregional recurrence (LRR), distant control, and overall survival (OS). Results: Fifteen patients were included. Nine (60%) patients presented with T4 disease and eight (53%) had positive ipsilateral cervical lymphadenopathy. Ten (67%) patients underwent trimodality therapy, including surgery followed by adjuvant radiation and concurrent systemic therapy. The median follow-up was 5.5 years (interquartile range, 4.8–6.1). The estimated 5-year rates of LRR, distant progression, and OS were 6%, 13%, and 87%, respectively. Conclusion: Despite only including AR+ SDC of the parotid, immunoprofiles, such as expression of HER-2, were highly variable, highlighting the potential to tailor systemic regimens based on individual histologic profiles in the future. Studies with larger patient numbers using tumor-specific molecular profiling and tumor heterogeneity analyses are justified to better understand the biology of these tumors. Molecularly informed treatment approaches, including the potential use of AR- and HER-2/Neu-directed therapies upfront in the definitive setting, may hold future promise to further improve outcomes for these patients. [ABSTRACT FROM AUTHOR]