Bacteriological follow-up of pulmonary tuberculosis treatment: a study with a simple colorimetric assay

The viability of Mycobacterium tuberculosis (MTB) in serial sputum specimens from persistently smear positive patients was evaluated. The assay was based on oxidation-reduction of Alamar Blue and Malachite Green dyes that change their color in response to MTB growth. A total of 280 sputum specimens from 40 persistently smear positive TB patients and 40 sputa from non-tuberculosis patients were digested, decontaminated and examined microscopically. To check the MTB viability, the sediments from decontaminated samples were inoculated into three culture media: Lowenstein-Jensen (LJ) slants, Alamar Blue and Malachite Green culture tubes. We found that out of 280 smear positive specimens, the LJ culture was positive in 124 (44%). The numbers of correctly identified S+/C+ cases by Alamar Blue and Malachite Green were 118 (95%) and 116 (93%), respectively. The mean time required for reporting the positive signal in Alamar Blue culture tubes was 9 versus 11 days by Malachite Green culture tubes. In the standard LJ culture media the average detection time was 27 days (P < 0.05). The sensitivity of LJ was 99%, Alamar Blue 95% and Malachite Green 93%. The specificity was 100%, 92% and 93%, respectively. The oxidation-reduction method is rapid, sensitive and inexpensive in monitoring the treatment response of patients with pulmonary TB. Thus, using this method can be of paramount importance, particularly in resource-constrained areas.     

Biosurfactant production by Mucor circinelloides: Environmental applications and surface‐active properties

Biosurfactants are structurally a diverse group of surface‐active molecules widely used for various purposes in industry. In this study, among 120 fungal isolates, M‐06 was selected as a superior biosurfactant producer, based on different standard methods, and was identified as Mucor circinelloides on the basis of its nucleotide sequence of the internal transcribed spacer (ITS) gene. M. circinelloides reduced the surface tension to 26 mN/m and its EI₂₄ index was determined to be 66.6%. The produced biosurfactant exhibited a high degree of stability at a high temperature (121°C), salinity (40 g/L), and acidic pH (2–8). The fermentation broth's ability to recover oil from contaminated sand was 2 and 1.8 times higher than those of water and Tween 80, respectively. The ability of biosurfactant to emulsify crude oil in the sea and fresh water was 64.9 and 48% respectively. This strain could remove 87.6% of crude oil in the Minimal Salt Medium (MSM) crude oil as the sole carbon source. The results from a primary chemical characterization of crude biosurfactant suggest that it is of a glycolipid nature. The strain and its biosurfactant could be used as a potent candidate in bioremediation of oil‐contaminated water, soil, and for oil recovery processes.     

Cross talk between energy cost and expression of Methyl Jasmonate-regulated genes: from DNA to protein

Journal of Plant Biochemistry and Biotechnology - Plant cell balances energy consumption for its different biological processes under oxidative circumstances. The aim of the present study is to...     

Variation of Chemical Constituents and Antiradical Capacity of Nine Ferulago angulata Populations from Iran

The present study was designed to assess the influence of geographical factors on essential oil (EO) composition, along with antiradical potential and phytochemical contents of Ferulago angulata (Schltdl .) Boiss (Apiaceae) extracts for the first time. The aerial parts were hydrodistilled by Clevenger apparatus and subjected to gas chromatography coupled with flame ionization detector (GC/FID) and mass spectroscopy (GC/MS). The EO yields were significantly different from populations ‘Mongar’ (south‐slope, 3000 m) with 1.34±0.06 % and ‘Male‐Amiri’ (north slope, 2600 m) with 0.18±0.05 % of total oil. Thirty‐nine compounds were identified from the EOs of nine populations. α‐Pinene was the predominant component ranging from 20.84 to 49.06 % in ‘Gandomkar’ (north‐slope, 2500 m) and ‘Mongar’ (3000 m), respectively. The methanolic extract of ‘Mongar’ (north‐slope at 2500 m) possessed the highest total phenolic contents. Also, this population logically exhibited potent antiradical activity using both 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays with EC₅₀ of 42.07±4.12 μg/mL and 8.34±0.21 mmol Trolox® equivalents/g, respectively. Due to its moderate free‐radical scavenging potential and high α‐pinene content, the population ‘Mongar’ might be considered as a perspective raw material in food and phytopharmaceutical industries.     

Retinoic acid and/or progesterone differentiate mouse induced pluripotent stem cells into male germ cells in vitro

Numerous reagents were employed for differentiating induced pluripotent stem cells (iPSCs) into male germ cells; however, the induction procedure was ineffective. The aim of this study was to improve the in vitro differentiation of mice iPSCs (miPSCs) into male germ cells with retinoic acid (RA) and progesterone (P). miPSCs were differentiated to embryoid bodies (EBs) in suspension with RA with or without progesterone for 0, 4, and 7 days. Then, the expression of certain genes at different stages of male germ cell development including Ddx4 (pre meiosis), Stra8 (meiosis), AKAP3 (post meiosis), and Mvh protein was examined in RNA and/or protein levels by real-time polymerase chain reaction or flow cytometry, respectively. The Stra8 gene expression increased in the RA groups on all days. But, expression of this gene declined in RA + P groups. In addition, an increased expression of Ddx4 gene was observed on day 0 in the P group. Also, a significant upregulation was observed in the expression of AKAP3 gene in the RA + P group on days 0 and 4. However, gene expression decreased in P and RA groups on day 7. The expression of Mvh protein significantly increased in the RA group on day 7. The Mvh expression was also enhanced in the P group on day 4, but it decreased on day 7, while this protein upregulated on day 0 and 7 in the RA + P group. The miPSCs have the capacity for in vitro differentiation into male germ cells by RA and/or progesterone. However, the effects of these inducers depend on the type of combination and an effective time.     

In Silico Design of Multimeric HN-F Antigen as a Highly Immunogenic Peptide Vaccine Against Newcastle Disease Virus

Application of molecular biology techniques to the production of new vaccines against different strains of the Newcastle disease virus (NDV) has been the subject of recent research reports. Development of improved techniques for genome sequencing has led to the recognition of protective mechanisms and the identification of possible candidate antigens. Such procedures could generate meaningful results regarding the virulence determinants of NDV. This study proposed an in silico approach by assembling potential and conserved epitopic regions of hemagglutinin–neuraminidase (HN) and fusion (F) glycoproteins of NDV to induce multiepitopic responses against the virus. Epitope predictions showed that the hypothetical synthetic construct could induce immature B and T cell epitopes that expect a high immune response because of their location in four distinct parts of the construct, namely the head, stalk and the heptad repeated regions known as the HRA and HRB domains. Most regions of the chimeric construct were found to have high antigenic propensity and surface accessibility, which further confirmed the strategy for selection of precise continuous and discontinuous epitopes of HN and F antigens. Thermodynamic folding of mRNA structures revealed correct folding of the RNA construct, indicating good stability of the mRNA to increase the efficiency of translation in the target host. The three-dimensional structure of the native HN-F chimeric protein was successfully generated and validated as a proper model which may define reliability, structural quality and conformation.     

Microsporum fulvum, an Ignored Pathogenic Dermatophyte: A New Clinical Isolation from Iran

Misidentifying with Microsporum gypseum has for a long time been accounted for less prevalence of the geophilic species, Microsporum fulvum in human dermatophytosis. We describe a new case of infection with the species in an Iranian young man. Direct examination of skin scrapings revealed a tinea corporis, and morphological study of the recovered isolate from the culture resulted in the identification of M. gypseum. However, PCR amplification of ITS1-5.8S rDNA-ITS2 region and subsequent ITS-RFLP and sequencing were indicative of M. fulvum as the true causative agent. To recognize M. fulvum in human infections and to validate the morphologically distinguished isolates of M. gypseum, the genetic-based identification is strongly recommended.     

Evaluation of antigenotoxicity effects of umbelliprenin on human peripheral lymphocytes exposed to oxidative stress

The protective properties of a prenylated coumarin, umbelliprenin (UMB), on the human lymphocytes DNA lesions were tested. Lymphocytes were isolated from blood samples taken from healthy volunteers. DNA breaks and resistance to H₂O₂-induced damage were measured using a single-cell microgel electrophoresis technique under alkaline conditions (comet assay). Human lymphocytes were incubated in UMB (10, 25, 50, 100, 200, and 400 μM) alone or a combination of different concentrations of UMB (10, 25, 50, 100, 200, and 400 μM) and 25 μM H₂O₂. Untreated cells, ascorbic acid (AA; 25, 50, 100, 200, and 400 μM) and H₂O₂ (25 μM) were considered as negative control, positive control, and the standard antioxidant agent for our study, respectively. Single cells were analyzed with “TriTek Cometscore version 1.5” software. The DNA damage was expressed as percent tail DNA. UMB exhibited a concentration-dependent increase in protection activity against DNA damage induced by 25 μM H₂O₂ (from 67.28% to 39.17%). The antigenotoxic activity of AA, in the range 0–50 μM, was greater than that of UMB. However, no significant difference (p > 0.05) in the protective activity was found between UMB and AA at concentrations of approximately higher than 50 μM.     

The stability evaluation of mesenchymal stem cells differentiation toward endothelial cells by chemical and mechanical stimulation

Adipose-derived mesenchymal stem cells (ADSCs) are adult multipotent cells able to differentiate into several cell lineages. Vascular endothelial growth factor (VEGF) and the shear stress associated with blood flow are considered as the most important chemical and mechanical cues that play major roles in endothelial differentiation. However, the stability of endothelial-specific gene expression has not been completely addressed yet. ADSCs in passage 3 were cultured inside the tubular silicon tubes and then exposed to VEGF or shear stress produced in a perfusion bioreactor. To investigate the differentiation, the expression levels of Flk-1, von Willebrand factor (vWF), and vascular endothelial-cadherin (VE-cadherin) were studied using Real-Time PCR. For studying the endothelial differentiation stability, mRNA levels of the genes were evaluated in certain time intervals after completion of the tests so as to determine whether the expression level of each gene in different time points was stable and remained constant or not. Application of VEGF and shear stress caused an elevation in endothelial cells’ specific genes. Although there are some changes following the days after application of mechanical and chemical stimuli, the gene expression results depicted significantly higher gene expression between sequential chemically and mechanically incited groups. In conclusion, stress alone can be a differentiating factor, by itself. Our results verified the efficient stable differentiation ability of the chemical and mechanical factors.