Overexpression of Prothymosin Alpha Predicts Poor Disease Outcome in Head and Neck Cancer

In our recent study, tissue proteomic analysis of oral pre-malignant lesions (OPLs) and normal oral mucosa led to the identification of a panel of biomarkers, including prothymosin alpha (PTMA), to distinguish OPLs from histologically normal oral tissues. This study aimed to determine the clinical significance of PTMA overexpression in oral squamous cell hyperplasia, dysplasia and head and neck squamous cell carcinoma (HNSCC).Immunohistochemistry of PTMA protein was performed in HNSCCs (n = 100), squamous cell hyperplasia (n = 116), dysplasia (n = 50) and histologically normal oral tissues (n = 100). Statistical analysis was carried out to determine the association of PTMA overexpression with clinicopathological parameters and disease prognosis over 7 years for HNSCC patients.<0.001). Chi-square analysis showed significant association of nuclear PTMA with advanced tumor stages (III+IV). Kaplan Meier survival analysis indicated reduced disease free survival (DFS) in HNSCC patients (p<0.001; median survival 11 months). Notably, Cox-multivariate analysis revealed nuclear PTMA as an independent predictor of poor prognosis of HNSCC patients (p<0.001, Hazard's ratio, HR = 5.2, 95% CI = 2.3–11.8) in comparison with the histological grade, T-stage, nodal status and tumor stage.Nuclear PTMA may serve as prognostic marker in HNSCC to determine the subset of patients that are likely to show recurrence of the disease

Bacteriophage-Resistant Mutants in Yersinia pestis: Identification of Phage Receptors and Attenuation for Mice

Background: Bacteriophages specific for Yersinia pestis are routinely used for plague diagnostics and could be an alternative to antibiotics in case of drug-resistant plague. A major concern of bacteriophage therapy is the emergence of phageresistant mutants. The use of phage cocktails can overcome this problem but only if the phages exploit different receptors. Some phage-resistant mutants lose virulence and therefore should not complicate bacteriophage therapy. Methodology/Principal Findings: The purpose of this work was to identify Y. pestis phage receptors using site-directed mutagenesis and trans-complementation and to determine potential attenuation of phage-resistant mutants for mice. Six receptors for eight phages were found in different parts of the lipopolysaccharide (LPS) inner and outer core. The receptor for R phage was localized beyond the LPS core. Most spontaneous and defined phage-resistant mutants of Y. pestis were attenuated, showing increase in LD 50 and time to death. The loss of different LPS core biosynthesis enzymes resulted in the reduction of Y. pestis virulence and there was a correlation between the degree of core truncation and the impact on virulence. The yrbH and waaA mutants completely lost their virulence. Conclusions/Significance: We identified Y. pestis receptors for eight bacteriophages. Nine phages together use at least seven different Y. pestis receptors that makes some of them promising for formulation of plague therapeutic cocktails. Most phage-resistant Y. pestis mutants become attenuated and thus should not pose a serious problem for bacteriophag

Phylogenetic and functional marker genes to study ammonia-oxidizing microorganisms (AOM) in the environment

The oxidation of ammonia plays a significant role in the transformation of fixed nitrogen in the global nitrogen cycle. Autotrophic ammonia oxidation is known in three groups of microorganisms. Aerobic ammonia-oxidizing bacteria and archaea convert ammonia into nitrite during nitrification. Anaerobic ammonia-oxidizing bacteria (anammox) oxidize ammonia using nitrite as electron acceptor and producing atmospheric dinitrogen. The isolation and cultivation of all three groups in the laboratory are quite problematic due to their slow growth rates, poor growth yields, unpredictable lag phases, and sensitivity to certain organic compounds. Culture-independent approaches have contributed importantly to our understanding of the diversity and distribution of these microorganisms in the environment. In this review, we present an overview of approaches that have been used for the molecular study of ammonia oxidizers and discuss their application in different environments

VISUALIZATION OF ELECTRICAL INHOMOGENEITIES IN HIGH-OHMIC SEMICONDUCTOR PLATES BY AN IONIZATION-TYPE PHOTOGRAPHIC SYSTEM

A device for rapid visualization of electrical and spatial inhomegeneities of a semi-insulating GaAs (rho greater-than-or-equal-to 10(6) OMEGA cm) is described. This visualizer is a modification of the ionization type photographic system in which a semiconducting plate is placed between transparent plane parallel electrodes in the gas discharge cell. The gas discharge gaps are formed between free surfaces of the semiconductor and electrodes. When a voltage is applied to the electrodes a discharge luminescence glows in the gap under uniform infrared illumination of the semiconductor. The uniformity of glowing over the semiconductor area is determined by electrical homogeneity and infrared absorptivity of the material. The main discharge glow patterns on both sides and after chemical etching are similar, which reflects the fact that the structural defects are continuous within the plate. The observed patterns give information about EL2 centres in the GaAs semiconductor. Technical data of the ionization-type visualizer of electrical inhomogeneities in a semiconducting plate are given

ENHANCEMENT OF THE RESOLUTION OF A SEMICONDUCTOR PHOTOGRAPHIC SYSTEM IN A MAGNETIC-FIELD

A method is described for enhancing the resolution R of a semiconductor photographic system by subjecting it to a homogenous magnetic field. Bi has been chosen as the photographic plate, since it has a large value of the cathode sputtering coefficient which is important in the formation of image by charged particle flux. A considerable increase of the resolution is observed when the applied magnetic field is parallel to the electric field between the electrodes. Effect of the magnetic field on the I - V characteristic of the system is discussed

Spatial stabilization of Townsend and glow discharges with a semiconducting cathode

The physical processes determining the functions of an ionization system and especially the discharge stabilization by the distributed resistance of a semiconducting cathode in such a system are studied. The current-voltage (I-U) characteristics of the system with a semiconducting GaAs cathode are obtained experimentally as functions of the gap pressure P (16-760 Torr) and inter-electrode distance d (10 mu m to 5 mm), which are varied for the first time over very wide ranges. The experiments showed that the presence of the distributed resistance affects the passage of the discharge current so that the discharge glows uniformly throughout the cathode surface and is not divided into separate filaments. The loss of stability was primarily due to the formation of a space charge of positive ions in the discharge gap which changed the discharge from the Townsend to the glow type