Nitrides as ammonia synthesis catalysts and as potential nitrogen transfer reagents

In this article, an overview of the application of selected metal nitrides as ammonia synthesis catalysts is presented. The potential development of some systems into nitrogen transfer reagents is also described

Hyaline Vascular-Type Castleman Disease Presenting as an Esophageal Submucosal Tumor: Case Report

Castleman disease is a relatively rare disorder of lymphoid tissue that involves the gastrointestinal tract in a variety of clinical and pathologic manifestations. A submucosal location has never been described in the medical literature. We report a case of esophageal Castleman disease involving thesubmucosal layer in a 62-year-old man, which was confirmed on pathology. Esophagography and CT demonstrated an intramural tumor, and a leiomyoma or leiomyosarcoma was suspected based on the known incidence of such tumors

The Diagnostic Value of Endoprobe for Small Esophageal Leiomyomas Derived from the Muscularis Mucosae

Esophageal leiomyoma derived from the muscularis mucosae (MM) is a rare condition, and the optimal modality for diagnosis and treatment is controversial. Endoscopic ultrasonography can provide an accurate image of esophageal layer structure, providing information on lesion suitability for potential endoscopic therapy. We attempted to investigate the diagnostic value of a transendoscopic balloon-tipped miniature ultrasonic endoprobe for small esophageal leiomyomas derived from MM. We resected 7 small esophageal leiomyomas derived from MM by endoscopic mucosal resection (EMR), all of which were diagnosed by a balloon-tipped endoprobe. The endosonographic and pathologic features of 7 cases of small esophageal leiomyomas derived from MM were compared. The balloon-tipped endoprobe clearly showed all 7 small esophageal leiomyomas derived from MM, even those under 5 mm in size (smallest lesion, 3.0 mm). The endosonographic characteristics of small esophageal leiomyomas derived from MM were a hypoechoic mass with smooth, regular, and a well-defined outer margin and homogenous inner echogram arising from the second hypoechoic layer. Complete resections were possible in all 7 cases by EMR without any complications. Tumor size was 3.0 - 13.5 mm (mean 7.8 mm) in maximum diameter. In all cases, endosonographic findings by endoprobe were exactly concordant with pathologic finding in determining the tumors depth in the esophageal wall, tissue origin and characteristics, growth pattern, and size. We detail the balloon-tipped endoprobe is a simple, convenient, and very useful in making accurate diagnosis of small esophageal leiomyomas derived from the MM and the appropriate applications of EMR

Coinfection of Viral Agents in Korean Children with Acute Watery Diarrhea

Currently, there are a few reports on viral coinfection that causes an acute watery diarrhea in Korean children. So, to evaluate the features of coinfectious viral agents in children with acute watery diarrhea, we enrolled 155 children with acute watery diarrhea from July 2005 to June 2006. Fecal samples were collected and evaluated for various viral infections such as rotavirus, norovirus, adenovirus and astrovirus. The mean (±standard deviation) age of the children was 2.71±2.37 yr. The detection rate of viral agents was most common in children between the ages of 1 and 3 yr. Rotavirus was detected in 63 children (41.3%), norovirus in 56 (36.2%), adenovirus in 11 (7.1%), and astrovirus in 1 (0.6%). Regarding rotavirus, there were 38 (60.3%) cases with monoinfection and 25 (39.7%) with coinfection. For norovirus, there were 33 (58.9%) cases with monoinfection and 23 (41.1%) with coinfection. Coinfection with rotavirus and norovirus was most common, and occurred in 20/155 cases (12.9%) including coinfection with adenovirus. So, rotavirus and norovirus were the most common coinfectious viral agents in our study population with acute watery diarrhea

The Significance of Bladder Trabeculation in the Female Lower Urinary System: An Objective Evaluation by Urodynamic Studies

This study aimed to investigate the relationship between bladder trabeculation, urinary function, and the stage of pelvic organ prolapse (POP). The medical records of 104 patients with POP who underwent cystoscopies and urodynamic studies were reviewed retrospectively. Age, incidence of detrusor instability, stage and site of POP, and the parameters of urodynamic studies of patients with and without bladder trabeculation were compared. The difference in the incidence of bladder trabeculation was estimated between patients with and without a suspected bladder outlet obstruction. There were significant differences in the patients' age, stage of POP, and maximal voiding velocity. Patients with a suspected bladder outlet obstruction had a significantly higher incidence of bladder trabeculation. In addition, patients with advanced stages of POP were also found to have a higher incidence of bladder trabeculation

Efficacy of Itraconazole Prophylaxis for Autologous Stem Cell Transplantation in Children with High-Risk Solid Tumors: A Prospective Double-Blind Randomized Study

∙ The authors have no financial conflicts of interest. Purpose: The risk of invasive fungal infection is greater for allogeneic hematopoietic stem cell transplantation (HSCT) than for autologous transplantation. Therefore, many transplantation centers use antifungal prophylaxis for allogeneic HSCT, however, there exists no standard guidelines or consensus regarding autologous HSCT. Materials and Methods: A prospective double-blind randomized study was conducted in autologous HSCT recipients who were divided into prophylaxis and empirical treatment groups, and we investigated the efficacy of itraconazole prophylaxis in pediatric autologous HSCT. Results: Total 87 autologous HSCT episodes in 55 children with high-risk solid tumors were studied. No invasive fungal infections occurred in either group. However, patients in the prophylaxis group had a significantly shorter duration of fever (p < 0.05) and received antibacterial treatment of shorter duration (p < 0.05) with fewer numbers of antibiotics (p < 0.05 for the use of second line antibiotics) than those in the empirica

A biologically plausible model of time-scale invariant interval timing

The temporal durations between events often exert a strong influence over behavior. The details of this influence have been extensively characterized in behavioral experiments in different animal species. A remarkable feature of the data collected in these experiments is that they are often time-scale invariant. This means that response measurements obtained under intervals of different durations coincide when plotted as functions of relative time. Here we describe a biologically plausible model of an interval timing device and show that it is consistent with time-scale invariant behavior over a substantial range of interval durations. The model consists of a set of bistable units that switch from one state to the other at random times. We first use an abstract formulation of the model to derive exact expressions for some key quantities and to demonstrate time-scale invariance for any range of interval durations. We then show how the model could be implemented in the nervous system through a generic and biologically plausible mechanism. In particular, we show that any system that can display noise-driven transitions from one stable state to another can be used to implement the timing device. Our work demonstrates that a biologically plausible model can qualitatively account for a large body of data and thus provides a link between the biology and behavior of interval timing

Genetic hitchhiking and resistance evolution to transgenic Bt toxins: insights from the African stalk borer Busseola fusca (Noctuidae)

Since transgenic crops expressing Bacillus thuringiensis (Bt) toxins were first released, resistance evolution leading to failure in control of pests populations has been observed in a number of species. Field resistance of the moth Busseola fusca was acknowledged 8 years after Bt maize was introduced in South Africa. Since then, field resistance of this corn borer has been observed at several locations, raising questions about the nature, distribution and dynamics of the resistance trait. Using genetic markers, our study identified four outlier loci clearly associated with resistance. In addition, genetic structure at neutral loci reflected extensive gene flow among populations. A realistically parameterised model suggests that resistance could travel in space at speed of several kilometres a year. Markers at outlier loci delineated a geographic region associated with resistance spread. This was an area of approximately 100 km radius, including the location where resistance was first reported. Controlled crosses corroborated these findings and showed significant differences of progeny survival on Bt plants depending on the origin of the resistant parent. Last, our study suggests diverse resistance mutations, which would explain the widespread occurrence of resistant larvae in Bt fields across the main area of maize production in South Africa

Identification of Retinoic Acid in a High Content Screen for Agents that Overcome the Anti-Myogenic Effect of TGF-Beta-1

Transforming growth factor beta 1 (TGF-β1) is an inhibitor of muscle cell differentiation that is associated with fibrosis, poor regeneration and poor function in some diseases of muscle. When neutralizing antibodies to TGF-β1 or the angiotensin II inhibitor losartan were used to reduce TGF-β1 signaling, muscle morphology and function were restored in mouse models of Marfan Syndrome and muscular dystrophy. The goal of our studies was to identify additional agents that overcome the anti-myogenic effect of TGF-β1.A high-content cell-based assay was developed in a 96-well plate format that detects the expression of myosin heavy chain (MHC) in C2C12 cells. The assay was used to quantify the dose-dependent responses of C2C12 cell differentiation to TGF-β1 and to the TGF-β1 Type 1 receptor kinase inhibitor, SB431542. Thirteen agents previously described as promoting C2C12 differentiation in the absence of TGF-β1 were screened in the presence of TGF-β1. Only all-trans retinoic acid and 9-cis retinoic acid allowed a maximal level of C2C12 cell differentiation in the presence of TGF-β1; the angiotensin-converting enzyme inhibitor captopril and 10 nM estrogen provided partial rescue. Vitamin D was a potent inhibitor of retinoic acid-induced myogenesis in the presence of TGF-β1. TGF-β1 inhibits myoblast differentiation through activation of Smad3; however, retinoic acid did not inhibit TGF-β1-induced activation of a Smad3-dependent reporter gene in C2C12 cells.Retinoic acid alleviated the anti-myogenic effect of TGF-β1 by a Smad3-independent mechanism. With regard to the goal of improving muscle regeneration and function in individuals with muscle disease, the identification of retinoic acid is intriguing in that some retinoids are already approved for human therapy. However, retinoids also have well-described adverse effects. The quantitative, high-content assay will be useful to screen for less-toxic retinoids or combinations of agents that promote myoblast differentiation in the presence of TGF-β1