African Journal of Parasitology Research

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (11), pp. 001-004, November, 2020. © International Scholars Journals

Full Length Research Paper

Multi-drug resistance in Acinetobacter baumannii strains isolated from the clinical specimens of three hospitals in Tehran-Iran

Sepideh Mostofi¹, Reza Mirnejad²*and Faramaz Masjedian³

¹Department of Biology, North Tehran Azad University, Tehran, Iran.

²Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

³Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.

Accepted 09 March, 2020

Abstract

The aim of this study is to carry out an investigation on multi-drug resistance in Acinetobacter baumannii strains that are isolated from clinical samples of three highly large hospitals in Tehran-Iran. This descriptive-cross sectional study was performed in three large hospitals in Tehran on 70 samples of Acinetobacter which were isolated from patients during April to November 2010. After identifying the species level by using culture and biochemical methods, in order to determine the sensitivity of 50 isolates of A. baumannii to 13 antibiotics, standard methods according to CLSI guidelines were performed. In this study, resistance to three or more than three classes of antibiotics multidrug resistance was defined. In this study, 50 A. baumannii strains, 12 A. lwoffii strains and other Acinetobacter species were isolated from patients. The majority of isolates were from blood specimens. Isolates of A. baumannii showed the highest resistance to cefepime, ceftazidime, aztreonam, norfloxacin, ofloxacin, ciprofloxacin and amikacin. Tobramycin and meropenem were considered as effective drugs in this study. Multi-drug resistance in these strains was 55.4%, respectively. Multi-drug resistant Acinetobacters are growing and are considered as an important threat for hospitalized patients, so a change in consumption patterns of antibiotics and control of hospital infections seems to be necessary.

Key words: Acinetobacter baumannii, nosocomial infection, multi-drug resistance, antibiogram.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (11), pp. 001-012, November, 2020. © International Scholars Journals

Full Length Research Paper

Endophytic bacteria isolated from the pneumatophores of Avicennia marina

S. Rylo sona janarthine¹*, P. Eganathan², T. Balasubramanian¹ and S. Vijayalakshmi¹

¹Centre of Advance Studies in Marine Biology, Annamalai University, Portonovo, Tamilnadu, India.

²M.S.Swaminathan Research Foundation, Chennai, Tamilnadu, India.

Accepted 07 September, 2020

Abstract

Plant-associated bacteria that live inside plant tissues without causing any harm to plants are defined as endophytic bacteria. Endophytic bacteria were isolated from the surface sterilized pneumatophores of Avicennia marina. Three isolates were selected based on their colonization and occurrence. The isolates SjAM16101 Gram positive rods, SjAM16102 Gram negative rods and SjAM16103 Gram negative rods were identified using 16S rRNA sequencing and identified as Bacillus sp., Enterobacter sp. and Sporosarcina aquimarina, respectively. The nucleotide sequence has been deposited under accession number GU930357 (Bacillus sp.), GU930358 (Enterobacter sp.) and GU930359 (S. aquimarina). Bacillus sp., fixed nitrogen, S. aquimarina produced siderophore and all the three strains solubilized phosphate molecule.

Key words: Endophytic bacteria, pneumatophores, Avicennia marina, 16S rRNA sequencing.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (11), pp. 001-003, November, 2020. © International Scholars Journals

Short Communication

Antimicrobial activities of ethanol extract of black grape

Abtahi H.¹, Ghazavi A.²* and Karimi M.¹

¹Research Center of Molecular and Medicine Arak University of Medical Sciences, Arak, Iran.

²Tuberculosis and Pediatric Infectious Research Center (TPIRC), Department of Immunology, School of Medicine, Arak University of Medical Sciences, Arak, Iran.

Accepted 09 September, 2020

Abstract

There is considerable interest in alternative/adjuvant approaches for the eradication of infections using biologically active compounds, especially antioxidants from plants. Phenolic compounds in grape products play important roles for antioxidant, anti-inflammatory, and antimicrobial effects. Grapes are rich sources of potentially bioactive polyphenols. This study was conducted to measure the antibacterial activity of ethanol extract of total grape (Vitis vinifera L., Vitaceae) against several pathogenic bacteria. Grape was extracted by percolation method. Aliquots of the extracts at variable concentrations were then incubated with different bacterial strains, and the antimicrobial activities of the ethanolic extracts from total grapes were determined by the minimum inhibitory concentration (MIC). Total grapes extract inhibited significantly, the growth of the tested bacterial strains. Among the bacterial strains tested, Staphylococcus aureus was the most susceptibleility. Results from these findings suggest that total grapes extract may be used as natural antibacterial for treatment of some diseases, especially local skin diseases.

Key words: Antimicrobial activity, grape, minimum inhibitory concentrations (MIC).

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (10), pp. 001-009, October, 2020. © International Scholars Journals

Full Length Research Paper

A novel one-component system, XvgA involved in regulation of bacterial growth and virulence of Xanthomonas campestris pv. campestris

Daqing Mao^{1, 2}*^, Jun Tao^{3, 4}, Chunxia Li^{3, 5}, Chao Luo¹, Linlin Zheng¹ and Chaozu He^{3, 6}

¹School of Life Sciences, Tsinghua University, Beijing 100084, China.

²School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, 110016, China.

³State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.

⁴CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.

⁵Graduate School of Chinese Academy of Sciences, Beijing 100039, China.

⁶Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, Hainan University, Haikou, Hainan 570228, China.

Accepted 24 August, 2020

Abstract

One-component systems were the simplest and the most effective signaling mechanism in bacteria. Per-ARNT-Sim (PAS) domains were important modules that play crucial roles in light or oxygen or redox signaling in bacteria, and most characterized GGDEF proteins involved in cyclic di-GMP (c-di-GMP) synthesis played crucial roles in c-di-GMP signaling in bacteria. In Xanthomonas campestris pv. Campestris (Xcc), xvgA encoded a protein containing both a PAS and a GGDEF domains. Deletion of xvgA altered bacterial morphology and significantly reduced not only Xcc virulence but also bacterial growth, the growth assays under different light conditions indicated that XvgA involved in light (red or far-red) signaling in Xcc. XvgA had been shown to possess diguanylate cyclase (DGC) activity that converted GTP to c-di-GMP in vitro. Moreover, the PAS domain was necessary for its DGC activity, and glutamic acid 98 (E98) site in the PAS domain was an active site, which was verified with bioinformatics and biochemical assays in vitro. These findings indicated that XvgA was an important one-component system involved in c-di-GMP and light signaling, which contributed to regulate Xcc growth, motility and virulence.

Key words: Xcc, PAS domain, c-di-GMP, one-component system.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (10), pp. 001-004, October, 2020. © International Scholars Journals

Full Length Research Paper

In vitro antimicrobial effect of silver nanoparticles on Lactococcus garvieae and Streptococcus iniae

Mehdi Raissy¹* and Mahsa Ansari²

¹Department of Food Hygiene and Aquatic Animal Health, Faculty of Veterinary Medicine, Islamic Azad University-Shahrekord Branch, Iran.

²Young Researchers Club, Islamic Azad University, Shahrekord Branch, Iran.

Accepted 09 September, 2020

Abstract

Antimicrobial effect of silver nanoparticles on two fish pathogens, Lactococcus garvieae and Streptococcus iniae was investigated by microdilution method. A total of 16 isolates of L. garvieae and S. iniae that were obtained from diseased rainbow trout during 2009 to 2011 were examined. Antimicrobial effects of the compound were evaluated according to the broth microdilution method by determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). According to the results MIC ranged from 1.12 to 5 µgml^-1 for L. garvieae and 1.12 to 2.5 µgml^-1 for S. iniae isolates. The mean MIC value was 2.59 and 2.1 for L. garvieae and S. iniae, respectively. The MBC was also calculated for the examined isolates as MBC ranged from 2.5 to 10 µgml^-1 with the mean of 5.27 and 3.57 for L. garvieae and S. iniae, respectively. The results showed that S. iniae strains were more sensitive to silver nanoparticles than L. garvieae strains. This study demonstrated the in vitro antimicrobial effects of silver nanoparticles on the examined bacteria although the efficacy of silver nanoparticles in fish ponds in different conditions needs more investigations.

Key words: Silver nanoparticles, Lactococcus garvieae, Streptococcus iniae.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (10), pp. 001-009, October, 2020. © International Scholars Journals

Full Length Research Paper

Effect of DLC-1 gene on tumour formation in nude mice inoculated with OVCAR-3

Liu HuiNa^{1, 2}, Shi HuiRong¹*, Zhang HaiLing¹, Wu KaiYuan¹, Zhang RuiTao¹ and Huang HaoLiang¹

¹Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, 450052, PR China.

²Department of Obstetrics and Gynecology, The Zhengzhou Central Hospital, 450007, PR China.

Accepted 14 August, 2020

Abstract

The aim of the present study was to examine effect of DLC-1 gene transfect OVCAR-3 cells in vivo on tumour growth in nude mice. Results showed that tumor development rate in OVCAR-3/DLC-1 group, OVCAR-3/pEGFP-C3 group and OVCAR-3 group were 87, 87 and 100%, respectively. After 40 days, tumour cells were not detected in peripheral blood of mice in every group. Low expression of P-FAK, P-P130 cas and P-JNK proteins was detected in group OVCAR-3/DLC-1, while high expression was found in group OVCAR-3/pEGFP-C3 and OVCAR-3. the brightness of the bands of P130cas mRNA, FAK mRNA and JNK mRNA in group OVCAR-3/DLC-1 became weaker, while the brightness of the bands become stronger in group OVCAR-3/pEGFP-C3 and group OVCAR-3. DLC-1, as a anti-tumor related target gene, possesses a promising future.

Key words: DLC-1, ovarian cancer, nude mice, transfection.