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Copyright of Gazi Medical Journal is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: To provide effective healing in the wound, various carbohydrate polymers are commonly utilized that are highly potent platforms as wound dressing films. In this work, novel antibacterial flexible polymeric hydrogel films were designed via crosslinking polymeric chitosan (CS) with folic acid-based carbon quantum dots (CQDs). To end this, folic acid as a bio-precursor is used to synthesize CQDs through the hydrothermal technique. The synthesized CQDs as a crosslinking agent was performed at different concentrations to construct nanocomposite hydrogel films via the casting technique. Also, gentamicin (GM), L-Arginine and glycerol were supplemented in the formulation of nanocomposite since their antibiotic, bioactivity and plasticizing ability, respectively. Results: The successful construction of films were verified with different methods (FT-IR, UV-Vis, PL, SEM, and AFM analyses). The GM release profile displayed a controlled release manner over 48 h with a low initial burst release in the simulated wound media (PBS, pH 7.4). Antibacterial and in vitro cytotoxicity results showed a significant activity toward different gram-positive and negative bacterial strains (about 2.5 ± 0.1 cm inhibition zones) and a desired cytocompatibility against Human skin fibroblast (HFF-1) cells (over 80% cell viability), respectively. Conclusion: The obtained results recommend CQDs-crosslinked CS (CS/CQD) nanocomposite as a potent antimicrobial wound dressing. [ABSTRACT FROM AUTHOR]

Objectives: Acroptilon repens (L.) DC is an Asian native plant belongs to the Asteraceae family. It has been cultivated the United States and Canada in recent years. This study investigated the effects of antibacterial, anti-biofilm, and cytotoxicity of A. repens ethanolic extract and its components. Materials and Methods: We used disk diffusion and well diffusion strategies to screen antimicrobial activity of A. repens against Staphylococcus aureus and Staphylococcus epidermidis. Then, the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of extract and fractions were determined by the small dilution broth methodology for S. aureus and S. epidermidis. The impact of extract and fractions on biofilm formation was evaluated by microtiter plate assay The MTT assay determined the toxicity effect of samples on Vero cells. The results are expressed because of the viability. Results: Results showed that A. repens extract and fragments inhibit the growth of gram-positive bacteria. The ethanolic extract and its fractions showed stronger inhibition zones for S. aureus and S. epidermidis. According to the antibiofilm test, the ethanolic extract and water fraction of A. repens have the highest antibiofilm effect on S. aureus and S. epidermidis. The value of LC50 (50% mortality) in MTT assay results was 30, 60, 30, and 2/5 mg/mL for ethanolic extract, chloroform, ethyl acetate and water fractions of A. repens, respectively. Conclusions: Extract of A. repens and its fractions have an antibacterial and antibiofilm effect on S. aureus and S. epidermidis without significant cytotoxic effect. [ABSTRACT FROM AUTHOR]

Objective(s): Pseudomonas aeruginosa is an opportunistic pathogen that is an important cause of nosocomial infections. This bacterium produces various virulence factors, among which exotoxin A is significantly involved in mortality and morbidity. In this study, we evaluated the immunogenicity of native exotoxin A extracted from the P. aeruginosa and its conjugation with gold nanoparticles in the animal model. Materials and Methods: Exotoxin A was first extracted and purified from the culture medium of P. aeruginosa PAO1 by selective precipitation and dialysis. The gold nanoparticles were prepared using the Turkevich method and conjugated to the prepared exotoxin A by electrostatic force. The size and conjugation were confirmed using electron microscopy and Fourier transform infrared spectrometry (FTIR), respectively. The immunogenicity of prepared ExoA-gold nanoparticles was investigated in the mice model. Results: The results indicated that nano-gold particles can be conjugated to the native exotoxin A with high efficiency. Immunogenicity investigation demonstrated that antibody titers produced against native exotoxin A and its conjugate to nano-gold particles are significant in a mouse model (P<0.005). Moreover, significant protection against 2×LD50 P. aeruginosa infection was observed in animals immunized with nano-gold-exotoxin A as compared with control groups (P=0.00). Conclusion: Our study indicated that exotoxin A can be produced with acceptable purity in the laboratory, and conjugated to gold nanoparticles. Based on these results nano-gold-exotoxin A conjugate is highly immunogenic and can be considered a potential vaccine candidate for P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

Intake of probiotic bacteria may improve or preserve insulin sensitivity. Fetuin-A and sestrin 3 have emerged as promising candidate biomarkers for crucial roles in insulin signaling pathway. Therefore, the effect of oral supplementation with the probiotic bacterium Lactobacillus delbrueckii subsp. lactis PTCC1057 on proteins involved in insulin signaling pathway was investigated in normal and streptozotocin (STZ)-induced diabetic mice. The 6–8-week-old female mice were divided into a non-diabetic control, diabetic control, and diabetic experimental and non-diabetic experimental groups (5 mice each group). Diabetic and non-diabetic experimental groups treated with 3 × 107 CFU mL−1L. delbrueckii subsp. lactis PTCC1057 by gavage feeding approach daily for 28 days. Serum glucose, fetuin-A, and sestrin 3 levels were measured by standard methods. The result showed that oral administration of L. delbrueckii significantly decreased serum glucose in comparison to diabetic control group (P = 0.01). Serum fetuin-A level was higher in diabetic control group than non-diabetic group and oral administration of L. delbrueckii subsp. lactis PTCC1057 significantly decreased fetuin-A level in diabetic experimental group in comparison with non-diabetic groups (P = 0.001). Sestrin 3 level significantly was lower in diabetic control group than non-diabetic control group (P = 0.03) and it significantly increased in diabetic experimental group in comparison with diabetic control group after intervention of L. delbrueckii subsp. lactis PTCC1057 (P = 0.02). The results show that feeding the STZ-induced diabetic mice with L. delbrueckii subsp. lactis PTCC1057 terminated to decrease in fasting blood glucose and fetuin-A level and increase in serum sestrin 3 level. Therefore, the L. delbrueckii subsp. lactis PTCC1057 can be considered as excellent candidate for future studies on diabetes mellitus. [ABSTRACT FROM AUTHOR]

Chemotherapy is standard treatments for many malignancies. However, in most cases, this method is not able to induce apoptosis and in many cases, with cancer recurrence, leads to patient death. There are several procedure to control and suppress malignant cells, but among these methods, administration of ɷ-3 fatty acids and ɷ-6 fatty due to their destructive effects on cancer cells is more prominent. Many clinical studies have shown beneficial effects of ɷ-3 and ɷ-6 fatty acids in cardiovascular disorders, asthma, rheumatoid arthritis, osteoporosis and in most cancers such as colon, breast, prostate and other malignancies. Studies showed that polyunsaturated fatty acids (PUFAs) have a toxic effect on cancer cells. However, the exact mechanism of how ɷ- fatty acids affect cancer cells is still unknown. In this review alternative issues of malignancies co-treatments agents such as PUFAs have been studied. Also, the latest known PUFAs mechanisms on malignancies have been described. [ABSTRACT FROM AUTHOR]

Objective(s): Pseudomonas aeruginosa is one of the most important bacterial pathogens in immunocompromised patients, and the lipopolysaccharide (LPS) of this organism is a key factor in virulence and both innate and acquired host responses to infection. In this study, we prepared a nanoconjugate vaccine composed of P aeruginosa detoxified lipopolysaccharide (D-LPS) and gold nanoparticles (Au NPs) and evaluated its potential as a vaccine candidate against P aeruginosa infections. Materials and Methods: LPS from P aeruginosa strain PAO1 was extracted by the hot phenol method with some modifications and then detoxified. Au NPs were synthesized by the reduction of hydrochloroauric acid trihydrate by sodium borohydride and then coupled to D-LPS via electrostatic interaction. Mice were subcutaneously injected in the tail base with 20 µg of D-LPS, D-LPS-Au NPs, Au NPs, and PBS. IgG titers were evaluated by ELISA and whole-cell ELISA methods. The immunized and control group mice were challenged with a 2xLD50 (7.5x107 CFU) of P aeruginosa strain PAO1. Results: Mice vaccinated with D-LPS and D-LPS-Au NPs elicited a significant amount of IgG antibodies. Nanoconjugated LPS generated a significantly higher antibody titer compared with D-LPS alone. Also, immunization of mice with D-LPS-Au NPs increased survival times against challenge with 7.5x107 CFU (2xLD50) of P aeruginosa strain PAO1. Conclusion: Our results showed that the suggested vaccine composed of P. aeruginosa D-LPS and Au NPs had a significant potential to protect against P aeruginosa infections. [ABSTRACT FROM AUTHOR]

Purpose: In the present study, the poly (ε-caprolactone)/cellulose nanofiber containing ZrO2 nanoparticles (PCL/CNF/ZrO2) nanocomposite was synthesized for wound dressing bandage with antimicrobial activity. Methods: PCL/CNF/ZrO2 nanocomposite was synthesized in three different zirconium dioxide amount (0.5, 1, 2%). Also the prepared nanocomposites were characterized by Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). In addition, the morphology of the samples was observed by scanning electron microscopy (SEM). Results: Analysis of the XRD spectra showed a preserved structure for PCL semi-crystalline in nanocomposites and an increase in the concentrations of ZrO2 nanoparticles, the structure of nanocomposite was amorphous as well. The results of TGA, DTA, DSC showed thermal stability and strength properties for the nanocomposites which were more thermal stable and thermal integrate compared to PCL. The contact angles of the nanocomposites narrowed as the amount of ZrO2 in the structure increased. The evaluation of biological activities showed that the PCL/CNF/ZrO2 nanocomposite with various concentrations of ZrO2 nanoparticles exhibited moderate to good antimicrobial activity against all tested bacterial and fungal strains. Furthermore, cytocompatibility of the scaffolds was assessed by MTT assay and cell viability studies proved the non-toxic nature of the nanocomposites. Conclusion: The results show that the biodegradability of nanocomposite has advantages that can be used as wound dressing. [ABSTRACT FROM AUTHOR]

Rapid emergence of antibiotic-resistant bacteria has made it harder for us to combat infectious diseases and to develop new antibiotics. The clustered regularly interspaced short palindromic repeats – CRISPR-associated (CRISPR-Cas) system, as a bacterial adaptive immune system, is recognized as one of the new strategies for controlling antibiotic-resistant strains. The programmable Cas nuclease of this system used against bacterial genomic sequences could be lethal or could help reduce resistance of bacteria to antibiotics. Therefore, this study aims to review using the CRISPR-Cas system to promote sensitizing bacteria to antibiotics. We envision that CRISPR-Cas approaches may open novel ways for the development of smart antibiotics, which could eliminate multidrug-resistant (MDR) pathogens and differentiate between beneficial and pathogenic microorganisms. These systems can be exploited to quantitatively and selectively eliminate individual bacterial strains based on a sequence-specific manner, creating opportunities in the treatment of MDR infections, the study of microbial consortia, and the control of industrial fermentation. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii is a nosocomial pathogen and gram-negative coccobacillus that is responsible for opportunistic infections, pneumonia, and infections of the urinary tract, bloodstream, skin, and soft tissue. This bacterium poses a major public health problem due to inducing resistance to several drugs, isolates, multidrug treatment, and occasionally pan drugs. Drug resistance is not only a major concern caused by A. baumannii but also is considered as the main challenge in many other pathogens. Several factors such as the efflux pump are associated with antibiotic resistance, biofilm production, and genetic mutations. In this review, A. baumannii is introduced in then some of the practical works conducted on the existing efflux pump are reviewed. The importance of the efflux pump is considered in this paper in relation to the antibiotic resistance and mechanisms developed for the inhibition of these pumps as well. [ABSTRACT FROM AUTHOR]

RNA helicase p68 or DEAD (Asp‐Glu‐Ala‐Asp) box polypeptide 5 (DDX5) is a unique member of the highly conserved protein family, which is involved in a broad spectrum of biological processes, including transcription, translation, precursor messenger RNA processing or alternative splicing, and microRNA (miRNA) processing. It has been shown that p68 is necessary for cell growth and participates in the early development and maturation of some organs. Interestingly, p68 is a transcriptional coactivator of numerous oncogenic transcription factors, including nuclear factor‐κβ (NF‐κβ), estrogen receptor α (ERα), β‐catenin, androgen receptor, Notch transcriptional activation complex, p53 and signal transducer, and activator of transcription 3 (STAT3). Recent studies on the role of p68 (DDX5) in multiple dysregulated cellular processes in various cancers and its abnormal expression indicate the importance of this factor in tumor development. Discussion of the precise role of p68 in cancer is complex and depends on the cellular microenvironment and interacting factors. In terms of the deregulated expression of p68 in breast cancer and the high prevalence of this cancer among women, it can be informative to review the precise function of this factor in the breast cancer. Therefore, an attempt will be made in this review to clarify the tumorigenic function of p68 in association with its targeting potential for the treatment of breast cancer. P68 or DDX5 is an RNA helicase that is dysregulated in breast cancer and can modulate the expression of several oncogenic factors in breast cancer. Therefore, it may be considered a potent therapeutic target in breast cancer. [ABSTRACT FROM AUTHOR]

Expression of recombinant protein that possess disulfide bonds especially Fab antibody fragment in periplasm of E. coli is the most favorable platform. But formation of inclusion bodies and inefficient translocation of desired protein to the periplasm is considerable obstacle threatening the advantages of E. coli expression system. Co-expression with molecular chaperones is remarkable consideration to solve this problem. In this study we evaluated the effect of co-expression of molecular chaperones and optimization condition on efficient periplasmic translocation of Fab antibody fragment. Plasmid pKJE7 was used for co-expression of DnaK/DnaJ/GrpE in BL21 cells and SHuffle strain (constantly expressing DsbC chaperon) were used for evaluation of chaperones effects. Periplasmic fraction was prepared by osmotic shock method and ELISA test were used for activity measurement. The Fab antibody purified by IMAC chromatography. The results indicated that co-expression of anti-TNF-α Fab with DnaK/DnaJ/GrpE in BL21 cells had a marked effect on the yield of periplasmic fraction but DsbC had no effect on periplasmic translocation. The optimal culture condition was found 0.1 mM IPTG concentration and 25 °C temperatures. SDS-PAGE analysis indicated that solubility increased to 42% of total Fab in Bl21 co-expressing DnaKJE. This study reports that co-expression with DnaK/DnaJ/GrpE markedly increases soluble expression of Fab antibody fragment in optimized condition. [ABSTRACT FROM AUTHOR]

Copyright of Ars Pharmaceutica is the property of Facultad de Farmacia de Granada and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Pseudomonas aeruginosa is one of the opportunistic pathogens that takes the advantage of patient's immunodeficiency and is one of the major causes of nosocomial infections. Multivalent vaccines such as those using the collection of secretory antigens and inactivated or killed whole-cell can be effective in preventing the infections. This study intended to evaluate the protective effect of P. aeruginosa whole-cell antigen in preventing the infections. Materials and Methods: In this study, sonicated multivalent antigen was provided and active immunization of female BALB/c mice aged 6-8 weeks (4 groups each with 7 mice) was carried out by subcutaneous, intraperitoneal and intramuscular administrations on days 0, 14 and 28. The fourth group was selected as the control group of the study. One week after each injection, on days 7, 21 and 35 blood samples were taken from mice and after isolating the serum, indirect ELISA was carried out to evaluate the produced IgG antibody against sonicated multivalent antigen of P. aeruginosa. Results: According to the results, due to the complexity of P. aeruginosa pathogenicity, using the multivalent vaccines such as the collection of somatic and secretory antigens, can be effective in the prevention of infections. ELISA results showed significant antibody production in subcutaneously, intraperitoneally and intramuscularly injected groups compared to the control group. Comparing the immunization of antigen based on the route of injection showed that there was no significant difference in induced immunization between the groups (subcutaneous, intraperitoneal and intramuscular injections). Moreover, immunized mice showed significant protection against intraperitoneal challenge with 7.5 × 107 CFU (2× LD50) P. aeruginosa. Conclusion: The sonicated antigens can have a more effective role in immunization and the prevention of mortality among mice infected with Pseudomonas. [ABSTRACT FROM AUTHOR]

Aims: Diabetes mellitus is a metabolic disorder characterised by inadequate pancreatic insulin secretion or the insulin present being unable to perform its function properly. Consistent with the beneficial effects of probiotics and their ability to lower glucose levels, an impact on diabetes treatment is also expected. The aim of this study was to evaluate the effect ofLactobacillus caseion various either biochemical parameters in a diabetic mice model. Methods: In the present study, 24 mice were divided into diabetic and control groups. Further, each group was categorised into two subgroups. The diabetic and control subgroups were fed carrot juice orLactobacillus caseiin carrot juice. Diabetes was induced by streptozotocin (STZ). For 30 days, the mice were fed 2 ml carrot juice, andLactobacillus caseiin carrot juice (with lactobacillus 109 cfu/ml) by gavage. Then, blood samples were collected to assay biochemical parameters. Results: The results of this study showed thatLactobacillus casei(ATCC39392) significantly reduced blood glucose (BG) levels in diabetic mice receiving the probiotic, but did not cause a significant change in BG levels in control mice receiving the probiotic. When comparing insulin, insulin-like growth factor I (IGF-I) and C-peptide in the four groups, it was found that insulin and C-peptide were significantly different in all groups except for the control group treated with a mixture of probioticLactobacillus caseiand carrot juice. Conclusion: Our results showed that probioticLactobacillus caseieffectively reduces BG levels in diabetic mice treated with this bacterium. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Microbiology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recombinant antibodies are increasingly being employed as therapeutic agents especially in combination with anti-cancer drugs. The single-chain antibody fragments are small antigen-binding proteins which provide the most commonly used antibody formats for diagnostic and therapeutic purposes. These antibody fragments have more rapid tumor penetration and clearance from the serum relative to full-length monoclonal antibodies. There are in vitro antibody-display technologies such as phage display, cell surface display, ribosome display and mRNA display that can be used to isolate high specificity and affinity single-chain antibodies against a wide variety of targets. We review these strategies for generation of stable and active antibody fragments in the present article. [ABSTRACT FROM AUTHOR]