New emerging roles of CD133 in cancer stem cell: Signaling pathway and miRNA regulation

Cancer stem cells (CSC) are rare immortal cells within a tumor that are able to initiate tumor progression, development, and resistance. Advances studies show that, like normal stem cells, CSCs can be both self-renewed and given rise to many cell types, therefore form tumors. A number of cell surface markers, such as CD44, CD24, and CD133 are frequently used to identify CSCs. CD133, a transmembrane glycoprotein, either alone or in collaboration with other markers, has been mainly considered to identify CSCs from different solid tumors. However, the exactness of CD133 as a cancer stem cell biomarker has not been approved yet. The clinical importance of CD133 is as a CSC marker in many cancers. Also, it contributes to shorter survival, tumor progression, and tumor recurrence. The expression of CD133 is controlled by many extracellular or intracellular factors, such as tumor microenvironment, epigenetic factors, signaling pathways, and miRNAs. In this study, it was attempted to determine: 1) CD133 function; 2) the role of CD133 in cancer; 3) CD133 regulation; 4) the therapeutic role of CD133 in cancers.     

Otomycosis in the South of Iran with a High Prevalence of Tympanic Membrane Perforation: A Hospital-Based Study

Mycopathologia - Otomycosis is a superficial infection of the external ear caused by fungal pathogens. The genera Aspergillus and Candida are considered the main fungal causative agents, with the...     

Compensatory Role of Insulin in the Extinction but Not Reinstatement of Morphine-Induced Conditioned Place Preference in the Streptozotocin-Induced Diabetic Rats

Neurochemical Research - Insulin receptors are distributed in the whole brain, including different parts of the reward circuit that modulate dopamine as the primary neurotransmitter implicated in...     

Peroxidase-producing actinobacteria from Algerian environments and insights from the genome sequence of peroxidase-producing Streptomyces sp. S19

International Microbiology - Unique environments often serve as a source of novel microorganisms with novel chemistries. In this study, telluric samples collected from different regions of Algeria...     

Should We Have Blind Faith in Bioinformatics Software? Illustrations from the SNAP Web-Based Tool

Bioinformatics tools have gained popularity in biology but little is known about their validity. We aimed to assess the early contribution of 415 single nucleotide polymorphisms (SNPs) associated with eight cardio-metabolic traits at the genome-wide significance level in adults in the Family Atherosclerosis Monitoring In earLY Life (FAMILY) birth cohort. We used the popular web-based tool SNAP to assess the availability of the 415 SNPs in the Illumina Cardio-Metabochip genotyped in the FAMILY study participants. We then compared the SNAP output with the Cardio-Metabochip file provided by Illumina using chromosome and chromosomal positions of SNPs from NCBI Human Genome Browser (Genome Reference Consortium Human Build 37). With the HapMap 3 release 2 reference, 201 out of 415 SNPs were reported as missing in the Cardio-Metabochip by the SNAP output. However, the Cardio-Metabochip file revealed that 152 of these 201 SNPs were in fact present in the Cardio-Metabochip array (false negative rate of 36.6%). With the more recent 1000 Genomes Project release, we found a false-negative rate of 17.6% by comparing the outputs of SNAP and the Illumina product file. We did not find any ‘false positive’ SNPs (SNPs specified as available in the Cardio-Metabochip by SNAP, but not by the Cardio-Metabochip Illumina file). The Cohen’s Kappa coefficient, which calculates the percentage of agreement between both methods, indicated that the validity of SNAP was fair to moderate depending on the reference used (the HapMap 3 or 1000 Genomes). In conclusion, we demonstrate that the SNAP outputs for the Cardio-Metabochip are invalid. This study illustrates the importance of systematically assessing the validity of bioinformatics tools in an independent manner. We propose a series of guidelines to improve practices in the fast-moving field of bioinformatics software implementation.     

Improved Assay for Quantifying a Redox Form of Angiotensinogen as a Biomarker for Pre-Eclampsia: A Case-Control Study

Objective

Angiotensinogen exists in two distinct redox forms in plasma, the oxidized sulfhydryl-bridge form and the reduced, unbridged, free thiol form. The oxidized form of angiotensinogen compared to the free thiol form preferentially interacts with renin resulting in increased generation of angiotensin. The predictive potential of the ratio of free-thiol to oxidized angiotensinogen in the plasma for pre-eclampsia was first suggested by the Read group in ref 10. We propose an improved method for determining the ratio and validate the method in a larger cohort of pregnant women.

Methods

Plasma samples from 115 individuals with pre-eclampsia and from 55 healthy pregnant control subjects were collected sequentially over a 2 year period. Using two distinct enzyme-linked immunosorbent assays (ELISAs) the plasma levels of total and free thiol angiotensinogen were quantified. The oxidized angiotensinogen plasma level is derived by subtracting the level of free thiol, reduced angiotensinogen from the total angiotensinogen levels in the plasma.

Results

The relative proportion of free thiol angiotensinogen, expressed as a percentage of that observed with an in-house standard, is significantly decreased in pre-eclamptic patients (70.85% ± 29.49%) (mean ± SD) as compared to healthy pregnant controls (92.98 ± 24.93%) (mean ± SD) p ≤ 0.0001. The levels of total angiotensinogen did not differ between the two groups.

Conclusion

Patients with pre-eclampsia had substantially lower levels of free thiol angiotensinogen compared to healthy pregnant controls, whilst maintaining similar total angiotensinogen levels in the plasma. Hence, elevated levels of plasma oxidized angiotensinogen may be a contributing factor to hypertension in the setting of pre-eclampsia.     

Otomycosis in Iran: A Review

Fungal infection of the external auditory canal (otitis externa and otomycosis) is a chronic, acute, or subacute superficial mycotic infection that rarely involves middle ear. Otomycosis (swimmer’s ear) is usually unilateral infection and affects more females than males. The infection is usually symptomatic and main symptoms are pruritus, otalgia, aural fullness, hearing impairment, otorrhea, and tinnitus. Fungal species such as yeasts, molds, dermatophytes, and Malassezia species are agents for otitis externa. Among molds, Aspergillus niger was described as the most common agent in the literature. Candida albicans was more prevalent than other yeast species. Otomycosis has a worldwide distribution, but the prevalence of infection is related to the geographical location, areas with tropical and subtropical climate showing higher prevalence rates. Otomycosis is a secondary infection and is more prevalent among swimmers. As a result, a higher incidence is reported in summer season, when more people interested in swimming. Incidence of otomycosis in our review ranged from 5.7 to 81 %, with a mean value of 51.3 %. Our results showed that 78.59 % of otomycosis agents were Aspergillus, 16.76 % were Candida species, and the rest (4.65 %) were other saprophytic fungi. Among Iranian patients, incidence of infection was highest in summer, followed by autumn, winter, and spring. In Iran, otomycosis was most prevalent at the age of 20–40 years and the lowest prevalence was associated with being <10 years old. The sex ratio of otomycosis in our study was (M/F) 1:1.53.     

Ultra pH‐sensitive detection of total and free prostate‐specific antigen using electrochemical aptasensor based on reduced graphene oxide/gold nanoparticles emphasis on TiO2/carbon quantum dots as a redox probe

The development of a rapid, sensitive, and straightforward detection method of prostate‐specific antigen (PSA) is indispensable for the early diagnosis of prostate cancer (PCa). This work relates an electrochemical method using functionalized single‐stranded DNA aptamer to diagnose PCa and benign prostate hyperplasia. The sensing platform relies on PSA recognition by aptamer/Au/GO‐nanohybrid‐modified glassy carbon electrode. Besides ferrocyanide TiO₂/carbon quantum dots (CQDs) probe is used to investigate the effect of nanoparticle‐containing electrolyte. Optimization of incubation time of aptamer/Au/GO‐nanohybrid and volume fraction of nafion were done using Design Expert 10 software reporting 42.4 h and 0.095% V/V, respectively. In ferrocyanide medium, PSA detection as low as 3, 2.96, and 0.85 ng mL⁻¹ was achieved with a dynamic range from 0.5 to 7 ng ml⁻¹, in accord with clinical values, using cyclic voltammetry, square wave voltammetry, and electrochemical impedance spectroscopy, respectively. Moreover, this sensor exhibited conspicuous performance in TiO₂/CQDs‐containing medium with different pH values of 5.4 and 8 to distinguish total PSA and free PSA, resulting in very low limit of detections, 0.028, and 0.007 ng ml⁻¹, respectively. The results manifested the proposed system as a forthcoming sensor in a clinical and point of care analysis of PSA.     

Protein synthesis,DNA degradation,and morphological changes during programmed cell death in labial glands of Manduca sexta

Labial glands of the tobacco hornworm Manduca sexta (Lepidoptera: Sphingiidae), homologues of Drosophila salivary glands, undergo programmed cell death (PCD) in a 4-day period during larva-to-pupa metamorphosis. The programmed death of the labial gland was examined by electron microscopy and measurement of protein synthesis as well as measurement of DNA synthesis, end-labeling of single strand breaks, and pulsed-field gel electrophoresis. One of the earliest changes observed is a sharp drop in synthesis of most proteins, coupled with synthesis of a glycine-rich protein, reminiscent of silk-like proteins. From a morphological standpoint, during the earliest phases the most prominent changes are the formation of small autophagic vacuoles containing ribosomes and an apparent focal dissolution of the membranes of the endoplasmic reticulum, whereas later changes include differing destruction at the lumenal and basal surfaces of the cell and erosion of the basement membrane. By the fourth day of metamorphosis, individual cells become rapidly vacuolated in a cell-independent manner. In the vacuolated cells on day 3, chromatin begins to coalesce. It is at this period that unequivocal nucleosomal ladders are seen and end-labeling in situ or electrophoretic techniques document single or double-strand breaks, respectively. DNA synthesis ceases shortly after the molt to the fifth instar, as detected by incorporation of tritiated thymidine and weak TUNEL labeling. Large size fragments of DNA are seen shortly after DNA synthesis ceases and thence throughout the instar, raising the possibility of potential limitations built into the cells before their final collapse. Dev. Genet. 21:249–257, 1997. © 1997 Wiley-Liss, Inc.