In vitro and ex vivo anti-diabetic and anti-hyperglycemic properties of Zataria multiflora essential oil

Molecular Biology Reports - The underlying mechanism involved in the onset of many diseases such as diabetes is oxidative stress. Zataria multiflora has a very high antioxidant power that can be...     

Preparation, characterization, and DNA binding studies of water-soluble quercetin--molybdenum(VI) complex

DNA binding studies of flavonoids are needed to understand the reaction mechanism and improve drugs that target DNA. Quercetin (Q) is one of the most common flavonoids that can chelate metal ions and interact with double-stranded DNA. In the present work, UV absorption spectrophotometry, viscosimetry, circular dichroism, and fluorescence spectroscopic techniques were employed to study the interaction of water-soluble quercetin--molybdenum(VI) complex [Q-Mo(VI)] with calf thymus DNA. The binding constants (K(b)) for the complex with DNA were estimated to be 2.9?×?10(3) through spectroscopic titrations. Upon addition of the complex, significant decreases were observed in the viscosity of calf thymus DNA. Circular dichroic spectra indicated that there are certain detectable conformational changes in the DNA double helix when complex was added. Further, competitive methylene blue binding studies with fluorescence spectroscopy have shown that the complex can bind to DNA through nonintercalative mode. The experimental results suggest that Q-Mo(VI) binds to DNA via an outside binding mode.     

Changes of antioxidative enzymes,lipid peroxidation and chlorophyll content in chickpea types colonized by different <Emphasis Type="Italic">Glomus</Emphasis> species under drought stress

In order to investigate the effects of Glomus species on some physiological characteristics of two chickpea types (Pirouz cultivar of Desi type and ILC-482 of Kabuli type) under non-stress (NS) and drought stress, an experiment was conducted using a factorial arrangement based on completely randomized design with three replications. Drought stress decreased shoot and total dry weight in plants. However inoculation of plants with mycorrhiza improved these traits. Leaf chlorophyll content was decreased, but leaf proline content and guaiacol peroxidases (EC 1.11.1.7) (POD), catalase (EC 1.11.1.6) (CAT), and ascorbate peroxidase (EC 1.11.1.11) (APX) activities were increased as a result of drought stress. Drought stress had no significant effect on soluble protein content and polyphenol oxidase (EC 1.10.3.1) (PPO) enzymatic activity in chickpea plants. In general, drought stress and especially severe drought stress increased membrane lipid peroxidation (MDA) in chickpea plants, which was more evident in non-inoculated than in inoculated plants. Inoculation of chickpea by AM significantly increased POD and PPO activities compared with non-inoculated chickpea, but had no effect on CAT activity and proline content of leaves. The reaction of chickpea cultivars to inoculation by AM species and irrigation levels were different. ILC-482 showed that antioxidant enzymes activities were more and thus less MDA compared with Pirouz cultivar. In general, the most POD and PPO activities were recorded for inoculated plants with G. etunicatum and G. versiform species, and the most APX activity was observed in plants inoculated with G. intraradices.     

Modeling of Tumor Progression in NSCLC and Intrinsic Resistance to TKI in Loss of PTEN Expression

EGFR signaling plays a very important role in NSCLC. It activates Ras/ERK, PI3K/Akt and STAT activation pathways. These are the main pathways for cell proliferation and survival. We have developed two mathematical models to relate to the different EGFR signaling in NSCLC and normal cells in the presence or absence of EGFR and PTEN mutations. The dynamics of downstream signaling pathways vary in the disease state and activation of some factors can be indicative of drug resistance. Our simulation denotes the effect of EGFR mutations and increased expression of certain factors in NSCLC EGFR signaling on each of the three pathways where levels of pERK, pSTAT and pAkt are increased. Over activation of ERK, Akt and STAT3 which are the main cell proliferation and survival factors act as promoting factors for tumor progression in NSCLC. In case of loss of PTEN, Akt activity level is considerably increased. Our simulation results show that in the presence of erlotinib, downstream factors i.e. pAkt, pSTAT3 and pERK are inhibited. However, in case of loss of PTEN expression in the presence of erlotinib, pAkt level would not decrease which demonstrates that these cells are resistant to erlotinib.     

Overexpression,one-step purification,and characterization of a type II cholesterol oxidase from a local isolate <Emphasis Type="Italic">Rhodococcus</Emphasis> sp. PTCC 1633

A 1.6 kb gene encoding a cholesterol oxidase (choR) from a local isolate, Rhodococcus sp. PTCC 1633 was cloned into pET23a and the highly expressed recombinant enzyme was purified from the cell lysate of IPTG-induced Escherichia coli BL21(DE3)pLysS with one-step absorption on cholesterol. The purified protein had a molecular mass of 55 kDa, isoelectric point at about pH 9.0 and absorption peaks at 280, 380 and 460 nm, indicating that the enzyme is a flavoprotein. The optimum pH and temperature for the recombinant enzyme were 7.0 and 50°C, respectively. Steady-state kinetic revealed that the cholesterol oxidase had a K _m of 32 μM. This study is the first report concerning expression and one-step purification of a gene encoding cholesterol oxidase from Rhodococcus spp. This study revealed that this enzyme is a type II cholesterol oxidase.     

Absence of mutations in GJB2 (Connexin-26) gene in an ethnic group of southwest Iran

BACKGROUND:

The common GJB2 gene mutation (35delG) has been previously reported from Iranian patients that were affected with nonsyndromic autosomal recessive deafness. We, therefore, for the first time, investigated the prevalence and frequency of the GJB2 gene mutation in the Iranian deaf population with Arabian origins.

MATERIALS AND METHODs:

We amplified and sequenced the entire coding sequence of the GJB2 gene from 61 deaf patients and 26 control subjects.

RESULT:

None of the analyzed samples revealed deafness-associated mutation.

CONCLUSION:

This finding differs from several reports from Iran as we have focused on the GJB2 gene that possesses various mutations as the cause of congenital recessive deafness.     

Safely removing cell debris with LC3‐associated phagocytosis

Phagocytosis and autophagy are two distinct pathways that degrade external and internal unwanted particles. Both pathways lead to lysosomal degradation inside the cell, and over the last decade, the line between them has blurred; autophagy proteins were discovered on phagosomes engulfing foreign bacteria, leading to the proposal of LC3‐associated phagocytosis (LAP). Many proteins involved in macroautophagy are used for phagosome degradation, although Atg8/LC3 family proteins only decorate the outer membrane of LC3‐associated phagosomes, in contrast to both autophagosome membranes. A few proteins distinguish LAP from autophagy, such as components of the autophagy pre‐initiation complex. However, most LAP cargo is wrapped in multiple layers of membranes, making them similar in structure to autophagosomes. Recent evidence suggests that LC3 is important for the degradation of internal membranes, explaining why LC3 would be a vital part of both macroautophagy and LAP. In addition to removing invading pathogens, multicellular organisms also use LAP to degrade cell debris, including cell corpses and photoreceptor outer segments. The post‐mitotic midbody remnant is another cell fragment, which results from each cell division, that was recently added to the growing list of LAP cargoes. Thus, LAP plays an important role during the normal physiology and homoeostasis of animals.     

Microbial production of testosterone and testololactone in the culture of <Emphasis Type="Italic">Aspergillus terreus</Emphasis>

Two metabolites were obtained by microbial transformation of androstendione in the culture of Aspergillus terreus PTCC 5283, a fungus isolated from soil. Their structures were established as testosterone and testololactone on the basis of the spectral data including ¹H NMR, ¹³C NMR, FTIR, MS and physical constants such as melting point and optical rotation. Aspergillus terreusproduced both metabolites after 3 days incubation at 27 °C. The bioconversion reactions observed were 17-carbonyl reduction and biological Baeyer–Villiger oxidation.     

Predictors of postoperative atrial fibrillation after coronary artery bypass graft surgery

Objectives

The present study was aimed to identify the preoperative, intraoperative, and postoperative predictors of AF in a pure cohort of the patients with coronary artery disease who underwent CABG surgery.

Methods

Between November 2005 and May 2006, 302 consecutive patients were included in this prospective study. All the relevant clinical, electrocardiographic, echocardiographic, and laboratory data were gathered in the included patients and they were also monitored for development of post-CABG AF.

Results

Postoperative AF occurred in 46 (15%) of patients. By univariate analysis, older age, P-wave abnormality in ECG, presence of mitral regurgitation, larger left atrium (LA), left main coronary artery involvement, failure to graft right coronary artery (RCA), and adrenergic use in ICU were significantly associated with occurrence of post-CABG AF (all P< 0.05). However, in the logistic regression model, age (OR: 1.067, 95%CI: 1.02-1.116, P=0.005), LA dimension (OR: 1.102, 95%CI: 1.017-1.1936, P=0.017), P-wave morphology (OR: 12.07, 95%CI: 3.35-48.22, P=0.0001), failure to graft RCA (OR: 3.57, 95%CI: 1.20-10.64, P=0.022), and postoperative adrenergic use (OR: 0.35, 95%CI: 0.13-0.93, P=0.036) remained independently predictive of postoperative AF.

Conclusion

The present study suggested that age, P-wave morphology, LA dimension, failure to graft right coronary artery, and postoperative adrenergic use were independent predictors of post-CABG AF. Therefore, clinical data, ECG and echocardiography may be useful in preoperative risk stratification of the surgical patients for the occurrence of post-CABG AF.     

Umbelliprenin from Ferula persica roots inhibits the red pigment production in Serratia marcescens

The chloroform extract of Ferula persica var. persica roots was found to inhibit red pigment production of Serratia marcescens. A bioguided fractionation study by preparative thin layer chromatography (PTLC) detected a fraction (Rf = 0.71, petroleum ether/EtOAc, 2:1 v/v), which was effective on depigmentation of Serratia marcescens. Using conventional spectroscopy methods, the active fraction was identified as umbelliprenin. Neither the chloroform extract nor the isolated umbelliprenin fraction showed any antibacterial activity against the test strain at a certain concentration. In contrast, they exhibited depigmentation zones on culture plates.