Serogroup distribution, diversity of exotoxin gene profiles, and phylogenetic grouping of CTX-M-1- producing uropathogenic Escherichia coli.

The emergence of CTX-M-1 producing Uropathogenic Escherichia coli (UPEC) has become a serious challenge. In addition to antimicrobial resistance, a number of virulence factors have been shown. Therefore, this study was designed to determine the prevalence of O- serogroups, phylogenetic groups, exotoxin genes, and antimicrobial resistance properties of CTX-M-1- producing UPEC. A total of 248 UPEC isolates were collected. The antibiotic resistance was performed, and PCR was used to detect the blaCTX-M1, exotoxins, serogroups and phylogroups of UPEC. Of 248 isolates, 95 (38.3%) harbored blaCTX-M-1. Of them, serogroups O1 and O25 were predominant, accounting for 20% and 13.7%, respectively. The hlyA was the dominant exotoxin gene (32.6%), followed by sat (28.4%), vat (22.1%), cnf (13.7%), picU (8.4%), and cdt (2.1%). The hlyA gene was significantly associated with pyelonephritis (P = 0.003). Moreover, almost half of the isolates (45.4%) belonged to phylogenetic group B2. Most of exotoxin genes were present in significantly higher proportions in group B2 isolates except cdt gene (P < 0.05). All of the isolates were susceptible to imipenem, nitrofurantoin, and fosfomycin. The CTX-M-1-producing UPEC strains causing nosocomial infections are more likely to harbor certain exotoxin genes, raising the possibility that this increase in virulence genes may result in an increased risk of complicated UTI.

Bacterial l-asparaginases for cancer therapy: Current knowledge and future perspectives.

l-Asparaginases hydrolyzing plasma l-asparagine and l-glutamine has attracted tremendous attention in recent years owing to remarkable anticancer properties. This enzyme is efficiently used for acute lymphoblastic leukemia (ALL) and lymphosarcoma and emerged against ALL in children, neoplasia, and some other malignancies. Cancer cells reduce the expression of l-asparaginase leading to their elimination. The l-asparaginase anticancerous application approach has made incredible breakthrough in the field of modern oncology through depletion of plasma l-asparagine to inhibit the cancer cells growth; particularly among children. High level of l-asparaginase enzyme production by Escherichia coli, Erwinia species, Streptomyces, and Bacillus subtilis species is highly desirable as bacterial alternative enzyme sources for anticancer therapy. Thermal or harsh conditions stability of those from the two latter bacterial species is considerable. Some enzymes from marine bacteria have conferred stability in adverse conditions being more advantageous in cancer therapy. Several side effects exerted by l-asparaginases such as hypersensitivity should be hindered or decreased through alternative therapies or use of immune-suppressor drugs. The l-asparaginase from Erwinia species has displayed remarkable traits in children with this regard. Noticeably, Erwinia chrysanthemi l-asparaginase exhibited negligible glutaminase activity representing a promising efficiency mitigating related side effects. Application of software such as RSM would optimize conditions for higher levels of enzyme production. Additionally, genetic recombination of the encoding gene would indisputably help improving enzyme traits. Furthermore, the possibility of anticancer combination therapy using two or more l-asparaginases from various sources is plausible in future studies to achieve better therapeutic outcomes with lower side effects.

Herbal medicine as an auspicious therapeutic approach for the eradication of Helicobacter pylori infection: A concise review.

Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5'-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1ß, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori.

Mycobacterium avium paratuberculosis and Mycobacterium avium complex and related subspecies as causative agents of zoonotic and occupational diseases.

Mycobacterium avium complex (MAC) and Mycobacterium avium paratuberculosis (MAP) cause zoonotic infections transmitted by birds and livestock herds. These pathogens have remained as serious economic and health threats in most areas of the world. As zoonotic diseases, the risk of development of occupational disease and even death outcome necessitate implementation of control strategies to prevent its spread. Zoonotic MAP infections include Crohn's disease, inflammatory bowel disease, ulcerative colitis, sarcoidosis, diabetes mellitus, and immune-related diseases (such as Hashimoto's thyroiditis). Paratuberculosis has classified as type B epidemic zoonotic disease according to world health organization which is transmitted to human through consumption of dairy and meat products. In addition, MAC causes pulmonary manifestations and lymphadenitis in normal hosts and human immunodeficiency virus (HIV) progression (by serotypes 1, 4, and 8). Furthermore, other subspecies have caused respiratory abscesses, neck lymph nodes, and disseminated osteomyelitis in children and ulcers. However, the data over the occupational relatedness of these subspecies is rare. These agents can cause occupational infections in susceptible herd breeders. Several molecular methods have been recognized as proper strategies for tracking the infection. In this study, some zoonotic aspects, worldwide prevalence and control strategies regarding infections due to MAP and MAC and related subspecies has been reviewed.

Seroepidemiology of HTLV-1 and HTLV-2 Infection in Neyshabur City, North-Eastern Iran, during 2010-2014.

BACKGROUND: Retroviruses of human T-lymphotropic viruses (HTLV-1 and HTLV-2) have been demonstrated to be endemic in the north-eastern region of Iran. This study was aimed to determine the HTLV-1 and HTLV-2 prevalence among healthy individuals in Neyshabur City during 2010-2014. METHODS: A total of 8054 blood samples were collected from healthy participants in Neyshabur, North-Eastern Iran. The blood samples were screened for the presence of specific antibodies against HTLV-1 and HTLV-2 by using ELISA according to the manufacturer's instructions. RESULTS: The overall seropositivity rate for HTLV-1 and HTLV-2 was found to be 6.55% (528 out of 8054) among participants. CONCLUSION: Both HTLV-1 and HTLV-2 were demonstrated to be at a high rate in healthy individuals. However, a smaller number of asymptomatic carriers were found in this study, as compared to those identified in previous investigations in the city.

Sero-prevalence of Helicobacter pylori Infection in Neyshabur, Iran, During 2010-2015.

BACKGROUNDS & OBJECTIVE: The Helicobacter pylori prevalence has continuously decreased during recent years in Iran. The current study aimed at determining H. pylori prevalence in Neyshabur city, Northeast Iran, during 2010-2015. METHODS: The current epidemiologic survey was conducted in Neyshabur from 2010 to 2015 to determine the prevalence of H. pylori infection. A total of 11596 participants (3681 male with the mean age of 31.7±6.2 years and 7915 female with mean age of 68.3±4.7 years) were included. The enzyme-linked immunosorbent assay kits for the detection of H. pylori and Stat Fax 3200® Microplate Reader (USA) with a sensitivity of 95% and specificity of 98% were used. Titers above 12 units were considered positive for IgG, IgA, and IgM (negative <8, equivocal 8 to 12, and positive >12 U). The Chi-square t test and F test were used to analyze data. RESULTS AND CONCLUSION: The overall IgA, IgG, and IgM seropositive samples among the study participants were 852 (7.2%), 9000 (72.8%), and 1256 (5.2%), respectively. The IgA seropositivity was significantly high among the age group above 51 years, compared with the other age groups. Moreover, the IgG and IgM seropositivity were significantly high among the age groups 41 to 50 and 31 to 40 years respectively, compared with the other age groups. There was no significant difference between male and female cases regarding IgA and IgG seropositive samples, but IgM level was significantly higher among females, compared with that of the male cases. Furthermore, there was no significant alteration in IgA, IgG, and IgM seropositivity during 2010-2014 in Neyshabur. The prevalence of H. pylori in Neyshabur was high in the healthy population. Furthermore, the H. pylori prevalence did not change from 2010 to 2014 in the studied city. Effective approaches to improve health, educational, and socioeconomic status should be implemented to minimize and control H. pylori infection.

Occurrence of SHV, TEM and CTX-M ß-Lactamase Genes Among Enteropathogenic Escherichia coli Strains Isolated From Children With Diarrhea.

BACKGROUND: Antibiotic resistance is widespread among diarrheagenic Escherichia coli in developing countries, where the overuse of antibiotics is common. Information regarding ß-lactamases, especially Extended-Spectrum ß-Lactamases (ESBLs) in diarrheagenic pathogens should be considered in clinical management when an optimal treatment is needed. OBJECTIVES: The main objective of this study was to investigate the prevalence of bla CTX-M , bla SHV and bla TEM ß-lactamase genes among enteropathogenic E. coli (EPEC) isolates in Tehran, Iran. MATERIALS AND METHODS: Stool specimens were collected from children with diarrhea during a 17-month period from 2011 to 2013. Routine biochemical tests were performed for identification of E. coli isolates. The isolates were further examined by PCR for the presence of eae, stx1, stx2 and bfp genes. EPEC isolates have been screened for different ß-lactamase genes. Genotyping EPEC isolates harboring bla CTX-M15 gene was performed through Multi-Locus VNTR Analysis (MLVA). RESULTS: Of 42 EPEC, eight isolates carried the bla CTX-M1 . None of the isolates carried bla CTX-M2 and bla CTX-M9 . The bla CTX-M15 variant was identified in all of bla CTX-M1 -positive isolates. Furthermore, bla SHV and bla TEM genes were detected in 40.5% (n = 17) and 19% (n = 8) of all EPEC isolates, respectively. No significant association was observed between the existence of bfp gene and presence of those ß-lactamase genes (P > 0.05). MLVA analysis revealed high genetic diversity among bla CTX-M15 -positive isolates. CONCLUSIONS: Our study emphasized the increasing role of ESBL genes, especially bla CTX-M15 in EPEC isolates.