Characterization of photosynthetically active duckweed (<Emphasis Type="Italic">Wolffia australiana</Emphasis>) in vitro culture by Respiration Activity Monitoring System (RAMOS)

The feasibility of oxygen transfer rate (OTR) measurement to non-destructively monitor plant propagation and vitality of photosynthetically active plant in vitro culture of duckweed (Wolffia australiana, Lemnaceae) was tested using Respiration Activity Monitoring System (RAMOS). As a result, OTR proofed to be a sensitive indicator for plant vitality. The culture characterization under day/night light conditions, however, revealed a complex interaction between oxygen production and consumption, rendering OTR measurement an unsuitable tool to track plant propagation. However, RAMOS was found to be a useful tool in preliminary studies for process development of photosynthetically active plant in vitro cultures.     

Potential antigen candidates for subunit vaccine development against Helicobacter pylori infection

Helicobacter pylori (H. pylori) is a resident bacterium in the stomach that accounts for 75% cases of gastric cancer. In this review, we comprehensively studied published papers on H. pylori vaccines using Google Scholar and NCBI databases to gather information about vaccines against H. pylori. Considering the pivotal roles of the enzyme urease (in production of NH₃ and neutralization of the acidic medium of the stomach), cytotoxin-associated gene A, and vacuolating cytotoxin A proteins in H. pylori infection, they could be the best candidates for the construction of recombinant vaccines. The outer membrane porins (Hop), blood group antigen-binding adhesin (BabA), sialic acid-binding adhesin (SabA), and outer inflammatory protein A, play significant roles in binding of bacterium to human gastric tissues, and because binding is the first step in bacterial fixation and colonization, these antigens also can be considered as suitable candidates for designing vaccines. Likely, other significant bacterial antigens, such as NapA (chemotactic factor for recruitment of human neutrophils and monocytes to the site of infection), duodenal ulcer promoting protein A (to promote duodenal ulcer), and Hsp60 (as a molecular chaperon for activation of urease enzyme), can be used in the construction of subunit vaccines. New vaccines in use currently, such as DNA vaccines and subunit vaccines, can efficiently replace the dead and attenuated vaccines. Nonetheless, the results show that urease enzyme is most used compared with bacterial components in the designing and construction of recombinant vaccines. The BabA and SabA antigens belong to the outer membrane porins family in H. pylori and are required for binding and fixation of the bacterium to the human gastric tissues.     

The interplay of Klotho with signaling pathway and microRNAs in cancers

Klotho (KL) gene has been accepted as an "aging suppressor" gene that encodes a single transmembrane protein in human known as Klotho which is commonly expressed in renal tubes. The interruption in the secretion of Klotho protein expedites aging whereas its high expression extends lifespan. The family of Klotho proteins has been reported to act as distinct receptors for endocrine fibroblast growth factors (FGFs), which manage multifarious metabolic processes. Further, the secreted Klotho is a hormonal factor that takes part in the ion channel organization. Numerous studies determined that this protein affects the function of a number of important signaling pathways, which may present an impact in tumorigenesis via the coordination of receptors located on them. This review article focuses on the effects of microRNAs on the performance of Klotho and how the interplay between Klotho and certain pathways like insulin-like growth factor, FGF, Wnt, and transforming growth factor β contribute to the biogenesis of cancer. The present study is also pointed at defining the molecular mechanisms of these interactions.     

Carcinogenic and Non-carcinogenic Risk Assessment of Heavy Metals in Groundwater Wells in Neyshabur Plain,Iran

The present work reports the As, Cr, Cu, Pb, Zn, and Fe concentrations of drinking water samples in Neyshabur Plain, Iran. This study aimed also to ascertain the potential consumers’ health risk of heavy metal intake. Heavy metal concentrations were analyzed by inductively coupled plasma optical emission spectrometry. The highest and lowest average values in the analyzed water samples were observed for Fe (9.78 ± 5.61 μg/L) and As (1.30 ± 2.99 μg/L), respectively. These values were well below the limits recommended by the World Health Organization and the Iranian national standard. Heavy metal pollution index and heavy metal evaluation index were used to evaluate drinking water quality. The risk index was calculated by chronic daily intake and hazard quotient according to the United States Environmental Protection Agency approach. Heavy metal pollution index in all the samples was less than 100, indicating that it is a low-level heavy metal. The total risk of all heavy metals in the urban environment varied from 40.164 × 10⁻⁷ to 174.8 × 10⁻⁷. In this research, the maximum average of risk belonged to lead and copper with the respective values of 60.10 × 10⁻⁷and 33.99 × 10⁻⁷ from the selected wells. However, considering the toxic effect of some elements, including Pb and As, in the chronic exposure of consumers, we suggest a continuous evaluation and monitoring of drinking water resources.

     

Metamaterial-Based Energy Harvesting for Detectivity Enhanced Infrared Detectors

Plasmonics - In this paper, we propose new detectivity enhanced infrared detectors in which metamaterial cells are used to harvest the IR energy. Analytical models are developed and numerically...     

Glaucomatous Patterns in Frequency Doubling Technology (FDT) Perimetry Data Identified by Unsupervised Machine Learning Classifiers

Purpose

The variational Bayesian independent component analysis-mixture model (VIM), an unsupervised machine-learning classifier, was used to automatically separate Matrix Frequency Doubling Technology (FDT) perimetry data into clusters of healthy and glaucomatous eyes, and to identify axes representing statistically independent patterns of defect in the glaucoma clusters.

Methods

FDT measurements were obtained from 1,190 eyes with normal FDT results and 786 eyes with abnormal FDT results from the UCSD-based Diagnostic Innovations in Glaucoma Study (DIGS) and African Descent and Glaucoma Evaluation Study (ADAGES). For all eyes, VIM input was 52 threshold test points from the 24-2 test pattern, plus age.

Results

FDT mean deviation was −1.00 dB (S.D. = 2.80 dB) and −5.57 dB (S.D. = 5.09 dB) in FDT-normal eyes and FDT-abnormal eyes, respectively (p<0.001). VIM identified meaningful clusters of FDT data and positioned a set of statistically independent axes through the mean of each cluster. The optimal VIM model separated the FDT fields into 3 clusters. Cluster N contained primarily normal fields (1109/1190, specificity 93.1%) and clusters G₁ and G₂ combined, contained primarily abnormal fields (651/786, sensitivity 82.8%). For clusters G₁ and G₂ the optimal number of axes were 2 and 5, respectively. Patterns automatically generated along axes within the glaucoma clusters were similar to those known to be indicative of glaucoma. Fields located farther from the normal mean on each glaucoma axis showed increasing field defect severity.

Conclusions

VIM successfully separated FDT fields from healthy and glaucoma eyes without a priori information about class membership, and identified familiar glaucomatous patterns of loss.     

Altered tubulin assembly dynamics with N-homocysteinylated human 4R/1N tau in vitro

Tau isoforms promote neuronal integrity through binding and stabilization of microtubule proteins (MTP). It has been shown that hyperphosphorylation of tau contributes to Alzheimer’s disease (AD) pathology and related tauopathies. However, other pathogenic modifications of tau have not been well characterized. It is well accepted that elevated level of homocysteine (Hcy) is associated with neurodegenerative diseases such as AD. As a result of N-homocysteinylation of lysine residues, Hcy becomes a component of proteins, as a protein–homocystamide adduct, which affects protein structure and function. Here we demonstrate that N-homocysteinylation of human tau (4R/1N isoform) inhibits its function via impaired tau–tubulin specific binding and MTP assembly dynamics in vitro.