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The optimum conditions for the fabrication of zein/Ag composite nanoparticles from ethanol/H2O cosolvents using electrospinning and the properties of the composite were investigated. The zein/Ag nanoparticles were characterized using field-emission scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis. The antibacterial activity of the zein/Ag composite nanoparticles was also investigated. The XRD patterns and TEM images indicate the coexistence of a zein matrix and well-distributed Ag nanoparticles. [ABSTRACT FROM AUTHOR]

Recombinant protein production in E. coli has several advantages over other expression systems. Misfolding, inclusion body formation, and lack of eukaryotic post translational modification are the most disadvantages of this system. Exporting of correctly folded proteins to the outside of reductive cytoplasmic environment through twin-arginine system could help to pass these limiting steps. Two signal sequences, TorA and SufI are used at N-terminal of human growth hormone (hGH) bearing DsbA gene sequence at C-terminal to enhance folding. The synthetic cassettes including the signal sequence, hGH and DsbA were transformed into E. coli BL21 (DE3) to study the effect of signal sequence and DsbA chaperone on translocation and folding of the protein. The results confirmed using signal sequence at N-terminal of targeted protein and coexpression with DsbA could transport proteins to the periplasmic space and culture media compared to control groups. Although there is no protein band of somatropin in SDS-Page of culture media samples when using SufI as signaling sequence, the study demonstrated TorA signal sequence could transport the target protein to the culture media. However, there was a considerable amount of hGH in periplasmic space when using SufI compared to control. [ABSTRACT FROM AUTHOR]

The aim of this study was to produce a recombinant protein consisting of the catalytic and translocation domains of diphtheria toxin for its later application as a vaccine candidate against Corynebacterium diphtheria. To achieve this goal, at first, the amino acid sequence of DT386 was used for prediction of T and B cell epitopes using on-line servers. The DT386 coding sequence was synthesized and subcloned into the NcoI and XhoI sites of pET28a plasmid and recombinant pET28a plasmid was used to transform Escherichia coli BL21 (DE3) host cells. Afterwards, recombinant cells were selected and subjected to induction of expression by 1 mM isopropyl β-D-1-thiogalactopyranoside, (IPTG). Expression of the desired protein was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting, and finally, the recombinant protein was purified using nickel affinity chromatography. The results of epitope prediction using on-line servers established the ability of DT386 for stimulation of immune system against diphtheria toxin. Restriction digestion of the recombinant plasmids using NcoI and XhoI enzymes confirmed the fidelity of cloning by producing a band of about 1200 bp. SDS-PAGE analysis following induction of expression and also purification step confirmed the expression of the desired protein by showing a band of about 45 kDa. In addition, Western blot analysis using anti-6X-His antibody confirmed the identity of the expected protein. In conclusion, in the present study we amplified and cloned the coding sequence of DT386 fragment, followed by its expression by E. coli BL21 (DE3) cells. Then, the expressed protein was purified and will be used for later studies of evaluation of its immunogenic properties. [ABSTRACT FROM AUTHOR]

Lead belongs to the heavy metal group and is considered as an environmental contaminant. Acute or chronic contact to lead can change the physiological function of human organs. One of the most important disorders following the lead exposure is neurotoxicity. Lead neurotoxicity consists of the neurobehavioral disturbances like cognitive impairment. The aim of the current study is to evaluate the possible protective effect of vitamin C (Vit C), vitamin B12 (Vit B12), omega 3 (ω-3), or their combination on the lead-induced memory disorder. Adult wistar rats were orally administered Vit C (120 mg/kg/day) or Vit B12 (1 mg/kg/day) or ω-3 (1000 mg/kg/day) or their combination for 3 weeks in groups of 7 animals each. Then lead acetate (15 mg/kg/day) was injected intraperitoneally for one week to all pretreated animals. The control group received normal saline as a vehicle while the positive control for cognitive impairment received just lead acetate. At the end of treatments animal memories were evaluated in Object Recognition Task. The results showed, although 15 mg/kg lead acetate significantly declines the memory-evaluating parameters, pretreatment with Vit C, Vit B12, ω-3, or their combination considerably inverted the lead induced reduction in discrimination (d2) index (P < 0.001) and recognition (R) index (P < 0.001, P < 0.05, P < 0.05, and P < 0.001, respectively). Our findings indicate while lead acetate impairs spatial memory in rat, administration of Vit C, Vit B12, ω-3, or their combination prior to the lead exposure inhibits the lead induced cognitive loss. There was no remarkable difference in this effect between the used supplements. [ABSTRACT FROM AUTHOR]

Tramadol hydrochloride, a synthetic opioid, acts via a multiple mechanism of action. Tramadol can potentially change the behavioral phenomena. The present study evaluates the effect of tramadol after single or multiple dose/s on the spatial memory of rat using object recognition task (ORT). Tramadol, 20 mg/kg, was injected intraperitoneally (i.p) as a single dose or once a day for 21 successive days considered as acute or chronic treatment respectively. After treatment, animals underwent two trials in the ORT. In the first trial (T1), animals encountered with two identical objects for exploration in a five-minute period. After 1 h, in the T2 trial, the animals were exposed to a familiar and a nonfamiliar object. The exploration times and frequency of the exploration for any objects were recorded. The results showed that tramadol decreased the exploration times for the nonfamiliar object in the T2 trial when administered either as a single dose (P<0.001) or as the multiple dose (P<0.05) compared to the respective control groups. Both acute and chronic tramadol administration eliminated the different frequency of exploration between the familiar and nonfamiliar objects. Our findings revealed that tramadol impaired memory when administered acutely or chronically. Single dose administration of tramadol showed more destructive effect than multiple doses of tramadol on the memory. The observed data can be explained by the inhibitory effects of tramadol on the wide range of neurotransmitters and receptors including muscarinic, N-methyl D-aspartate, AMPA as well as some second messenger like cAMP and cGMP or its stimulatory effect on the opioid, gama amino butyric acid, dopamine or serotonin in the brain. [ABSTRACT FROM AUTHOR]

Depressive disorders are more common among persons with chronic diseases such as inflammatory bowel disease and anti-inflammatory effect of some antidepressants such as amitriptyline has been reported. Acetic acid colitis was induced in both reserpinised (depressed) and non-reserpinised (normal) rats. Reserpinised groups received reserpine (6 mg/kg, i.p.) one hour prior to colitis induction. Then Amitriptyline (5, 10, 20 mg/kg, i.p.) was administered to separate groups of male Wistar rats. All treatments were carried out two hours after colitis induction and continued daily for four days. Dexamethasone (1 mg/kg) and normal saline (1 mL/kg) were used in reference and control groups, respectively. At day five, animals were euthanized and colonic tissue injuries were assessed macroscopically and pathologically. Myeloperoxidase activity as a marker of neutrophil infiltration was also measured in colonic tissues. Results showed that reserpine (6 mg/kg, i.p.) intensified colitic condition. Compared to control, amitriptyline (10, 20 mg/kg) and dexamethasone significantly decreased weight of colon and ulcer index in normal and reserpine-induced depressed rats. Myeloperoxidase activity and pathological assessments also proved anti-inflammatory effect of amitriptyline. Our results suggest that amitriptyline, a tricyclic antidepressant, could reduce inflammatory and ulcerative injuries of colon both in normal and depressed rats. So among the wide spread anti-depressant drugs, amitriptyline is a good choice to treat depression comorbidities in patients with IBD. [ABSTRACT FROM AUTHOR]

Glutamate decarboxylase enzyme produces γ-aminobutyric acid (GABA) in a non-reversible decarboxylation reaction of glutamate. GABA is a major inhibitory neurotransmitter of the brain and it is also present at high concentration in other organs such as pancreatic islets. GABA has effects on blood pressure, diabetes, inflammation, sleeplessness and depression. Some bacteria such as Lactobacillus strains are capable of GABA production. Identification of these bacteria is important both for researchers and industry. The aim of this study was molecular gene cloning and sequencing of glutamate decarboxylase (gad) from Lactobacillus delbrueckii subsp. bulgaricus ATCC 11842 and Lactobacillus reuteri ATCC 23272. These strains were cultured in MRS medium at 37°C for 24 hours. For cloning gad gene from these strains, polymerase chain reaction (PCR) was performed using specific primers designed by Oligo7 software. PCR production was extracted from agarose gel and was inserted into PGEM-T vector using T4 DNA ligase enzyme and then it was transformed to E. coli XL1Blue. In the final step, white colonies were selected and after plasmid extraction, the existence of gad gene in recombinants was confirmed by PCR. Gad gene was cloned from Lactobacillus delbrueckii subsp. bulgaricus ATCC 11842 and Lactobacillus reuteri ATCC 23272. It is for the first time that the gad gene sequences from these bacteria were registered on NCBI with accession numbers KF751355 and KF751352 respectively. The result of this research indicates that the two aforementioned bacteria contain glutamate decarboxylase gene and therefore they possibly can be used for industrial γ-aminobutyric acid production. [ABSTRACT FROM AUTHOR]

Psychological disorders such as depression have more prevalence in inflammatory bowel disease patients and can exacerbate the clinical course of the disease, so anti-depressant therapy may have a potential to positively impact the disease course. On the other hand several antidepressant drugs have shown antiinflammatory and immunomodulatory properties. Thus, this study aimed to explore the beneficial effects of venlafaxine on experimental colitis in normal and reserpinised depressed rats. Acetic acid colitis was induced in both reserpinised and non-reserpinised rats. Reserpinised groups received reserpine at dose of 6 mg/kg i.p.1 h prior to colitis induction and then treated with venlafaxine at doses of 10, 20, 40 mg/kg given i.p. 2 h after induction of colitis and daily for 4 consecutive days. Non-reserpinised groups treated with 10, 20, 40 mg/kg venlafaxine i.p. 2 h after the induction of colitis and daily for 4 successive days. Dexamethasone (1 mg/kg, i.p.) was used as reference drug. Colonic inflammation was evaluated using macroscopic, histological and myeloperoxidase activity measurements. Results showed that reserpine at dose of 6 mg/kg exacerbated the colitis damage. Compared to acetic acid control, venlafaxine at dose of 40 mg/kg as well as dexamethasone significantly improved colitis parameters in both reserpinised and non-reserpinised animals. Venlafaxine reduced inflammatory injury in this animal model of induced ulcerative colitis. These effects are probably mediated first through depressive behavioral changes that could be mediated through the brain-gut axis and second for the anti-inflammatory effect of the drug. [ABSTRACT FROM AUTHOR]