Many snake venoms comprise different factors, which can either promote or inhibit the blood coagulation pathway. Coagulation disorders and hemorrhage belong to the most prominent features of bites of the many vipers. A number of these factors interact with components of the human blood coagulation. This study is focused on the effect of Echis carinatus snake venom on blood coagulation pathway. Anticoagulant factors were purified from the Iranian Echis carinatus venom by two steps: gel filtration (Sephadex G-75) and ion-exchange (DEAE-Sephadex) chromatography, in order to study the anticoagulant effect of crude venom and their fractions. The prothrombin time was estimated on human plasma for each fraction. Our results showed that protrombin time value was increase from 13.4 s to 170 s for F2C and to 280 s for F2D. Our study showed that these fractions of the venom delay the prothrombine time and thus can be considered as anticoagulant factors. They were shown to exhibit proteolytic activity. The molecular weights of these anticoagulants (F2C, F2D) were estimated by SDS/PAGE electrophoresis. F2C comprises two protein bands with molecular weights of 50 and 79 kDa and F2D a single band with a molecular weight of 42 kDa.

Abstract:The venom of Echis carinatus is rich in proteins and peptides effective on the hemostatic system. This venom is contains metalloproteinase which convert prothrombin to meizothrombin. The prothrombin activator which leads to the formation of small blood clots inside the blood vessels throughout the body. To understand the mechanism of the effects of Iranian Echis carinatus venom, the effects of E. carinatus on human and Wistar rat plasma, plasma proteins (prothrombin and fi brinogen) and blood coagulation were studied. Proteolytic activity of the crude venom on blood coagulation factors such as prothrombin, partial thromboplastin and fi brinogen times were studied. In the present study the PT test for human plasma was reduced from 13.4 s (± 0.59) to 8.6 s (± 0.64) when human plasma was treated with crude venom (concentration of venom was 1 mg/ml) and for rat plasma PT was reduced from 14.5 s (± 0.47) to 8 s (± 0.49). Some possible biological and biochemical effects of IEc crude venom were investigated. The blood coagulation in human and in rat were investigated in vivo and in-vitro. In this paper, we show that the procoagulant action of Echis carinatus venom is due in part to a protein component that activates prothrombin and the procoagulant activity on human and rat plasma was evaluated (Tab. 2, Fig. 2, Ref. 31). Text in PDF www.elis.sk.

Background: The emergence and spread of metallo-beta-lactamase (MBL)-producing Klebsiella pneumoniae are growing global public health concerns. One of the most common mechanisms of carbapenem resistance is the production of MBLs, including Verona Integron-encoded Metallo-beta-lactamase (VIM), imipenemase (IMP), and New Delhi metallo-beta-lactamase (NDM). Objectives: This study aimed to investigate MBLs production among K. pneumoniae isolates. Methods: In this study, 240 K. pneumoniae isolates were collected from clinical samples in three clinical centers of Isfahan, Iran, during February 2017 and November 2018. All isolates were identified using biochemical, microbiological, and molecular methods, and then antimicrobial susceptibility tests were performed to find MBL-producing isolates via phenotypic and genotypic detection methods. Moreover, the minimum inhibitory concentration (MIC) of antibiotics against MBL-positive strains was determined by E-test. Eventually, the clonal relatedness of the MBL-positive strains was analyzed using both multilocus sequence typing (MLST) and rep-PCR. Results: Overall, 33.7% (81/240) of the isolates were resistant to carbapenems, among which 25 (30.8%) were considered MBL-positive. Among 81 strains resistant to carbapenems, genes encoding FimH, rmpA, and mrkD were detected in 87.6% (71/81), 11.1% (9/81), and 67.95% (55/81) of the isolates, respectively. Besides, TEM and SHV as antibiotic resistance genes were detected in 49.3% (40/81) and 80.2% (65/81) of the isolates. But, magA was not detected in any of the tested isolates. The PCR results revealed that blaVIM-1 was the most prevalent gene (13.6%; 11/81), while both blaIMP-1 and blaNDM-1 were only detected in two isolates. Multilocus sequence typing demonstrated that 15 MBL producers belonged to three sequence types (ST): 11 to ST23, two to ST1147, and two to ST15. Finally, rep-PCR typing showed similar fingerprints with MLST, except for ST23, such that ST23 was discriminated in two clonal groups, suggesting the greater discriminatory power of rep-PCR. Conclusions: Here, we reported the emergence of MBL-producing K. pneumoniae in clinical centers of Isfahan, Iran. The findings are alarming and represent the urgent need for the application of infection control programs.

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Paratuberculosis caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic enteritis in ruminants. Among molecular components of MAP, protein P34 was identified as specific and immunodominant. Here, we describe the production of polyclonal antibodies with defined specificity for P34. Polyclonal antibodies were generated from New Zealand white rabbit. Animals were immunized at a certain time period with purified P34, MAP antigens and Freund's adjuvant. Antibodies were purified from serum by ion exchange chromatography. Western blotting analysis was used for evaluation of interaction between 34 kDa protein and antibodies.