scholarly journals Ontogenetic Change in the Venom of Mexican Black-Tailed Rattlesnakes (Crotalus molossus nigrescens)

Toxins ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 501 ◽  
Author(s):  
Miguel Borja ◽  
Edgar Neri-Castro ◽  
Rebeca Pérez-Morales ◽  
Jason Strickland ◽  
Roberto Ponce-López ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Snake Venom ◽  
Serine Proteinases ◽  
Ontogenetic Changes ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Venom Composition ◽  
Hemorrhagic Activity ◽  
Ecological Implications ◽  
Total Body

Ontogenetic changes in venom composition have important ecological implications due the relevance of venom in prey acquisition and defense. Additionally, intraspecific venom variation has direct medical consequences for the treatment of snakebite. However, ontogenetic changes are not well documented in most species. The Mexican Black-tailed Rattlesnake (Crotalus molossus nigrescens) is large-bodied and broadly distributed in Mexico. To document venom variation and test for ontogenetic changes in venom composition, we obtained venom samples from twenty-seven C. m. nigrescens with different total body lengths (TBL) from eight states in Mexico. The primary components in the venom were detected by reverse-phase HPLC, western blot, and mass spectrometry. In addition, we evaluated the biochemical (proteolytic, coagulant and fibrinogenolytic activities) and biological (LD50 and hemorrhagic activity) activities of the venoms. Finally, we tested for recognition and neutralization of Mexican antivenoms against venoms of juvenile and adult snakes. We detected clear ontogenetic venom variation in C. m. nigrescens. Venoms from younger snakes contained more crotamine-like myotoxins and snake venom serine proteinases than venoms from older snakes; however, an increase of snake venom metalloproteinases was detected in venoms of larger snakes. Venoms from juvenile snakes were, in general, more toxic and procoagulant than venoms from adults; however, adult venoms were more proteolytic. Most of the venoms analyzed were hemorrhagic. Importantly, Mexican antivenoms had difficulties recognizing low molecular mass proteins (<12 kDa) of venoms from both juvenile and adult snakes. The antivenoms did not neutralize the crotamine effect caused by the venom of juveniles. Thus, we suggest that Mexican antivenoms would have difficulty neutralizing some human envenomations and, therefore, it may be necessary improve the immunization mixture in Mexican antivenoms to account for low molecular mass proteins, like myotoxins.

scholarly journals Size Matters: An Evaluation of the Molecular Basis of Ontogenetic Modifications in the Composition of Bothrops jararacussu Snake Venom

Toxins ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 791
Author(s):  
Luciana A. Freitas-de-Sousa ◽  
Pedro G. Nachtigall ◽  
José A. Portes-Junior ◽  
Matthew L. Holding ◽  
Gunnar S. Nystrom ◽  
...  
Keyword(s):  
Gene Expression ◽  
Snake Venom ◽  
Molecular Basis ◽  
Molecular Mechanisms ◽  
Venom Gland ◽  
Ontogenetic Changes ◽  
Bothrops Jararacussu ◽  
Phospholipases A2 ◽  
Venom Composition ◽  
Putative Toxin

Ontogenetic changes in venom composition have been described in Bothrops snakes, but only a few studies have attempted to identify the targeted paralogues or the molecular mechanisms involved in modifications of gene expression during ontogeny. In this study, we decoded B. jararacussu venom gland transcripts from six specimens of varying sizes and analyzed the variability in the composition of independent venom proteomes from 19 individuals. We identified 125 distinct putative toxin transcripts, and of these, 73 were detected in venom proteomes and only 10 were involved in the ontogenetic changes. Ontogenetic variability was linearly related to snake size and did not correspond to the maturation of the reproductive stage. Changes in the transcriptome were highly predictive of changes in the venom proteome. The basic myotoxic phospholipases A2 (PLA2s) were the most abundant components in larger snakes, while in venoms from smaller snakes, PIII-class SVMPs were the major components. The snake venom metalloproteinases (SVMPs) identified corresponded to novel sequences and conferred higher pro-coagulant and hemorrhagic functions to the venom of small snakes. The mechanisms modulating venom variability are predominantly related to transcriptional events and may consist of an advantage of higher hematotoxicity and more efficient predatory function in the venom from small snakes.

Identification of a new truncated form and deamidation products of fibrinopeptide B released by thrombin from human fibrinogen

2006 ◽  
Vol 96 (09) ◽  
pp. 302-308 ◽  
Author(s):  
Barbara Cardinali ◽  
Gianluca Damonte ◽  
Luca Melone ◽  
Annalisa Salis ◽  
Francesca Tosetti ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Molecular Mass ◽  
Aspartic Acid ◽  
Pyroglutamic Acid ◽  
Truncated Form ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Ms Analysis ◽  
Capillary Electrophoretic

SummaryQuantification of fibrinopeptides release is widely used to investigate fibrinogen activation, and standard chromatographic or capillary electrophoretic procedures are readily available. However, in the analyses of fibrinopeptide mixtures derived from the action of thrombin on human fibrinogen, a few unidentified peaks are usually present. The composition of these peaks was studied by reverse-phase HPLC/MS, revealing a single major anomalous peptide having a molecular mass of 1384.4. A further MS/MS analysis allowed the identification of this form, as a Nterminally truncated fibrinopeptideB (fpB) lacking the first two residues (pyroglutamic acid and glycine). This previously unidentified, relatively low-abundance form (∼7%) has been found consistently in our fibrinopeptides preparations, and analysis of the parent Bβ-chain suggest that it is likely present in circulating fibrinogen. In addition, deamidated forms of all fpB species (including desArgB), resulting from the conversion of asparagine to aspartic acid, were also identified. Overall, these previously unreported forms constitute a substantial amount of fpB (up to ∼17% of the total), and should be taken into account for a reliable quantitative analysis of fpB release.

scholarly journals The genetics of venom ontogeny in the eastern diamondback rattlesnake (Crotalus adamanteus)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3249 ◽  
Author(s):  
Darin R. Rokyta ◽  
Mark J. Margres ◽  
Micaiah J. Ward ◽  
Elda E. Sanchez
Keyword(s):  
Snake Venom ◽  
Venom Gland ◽  
Ontogenetic Changes ◽  
Intraspecific Divergence ◽  
Full Characterization ◽  
Venom Composition ◽  
Significant Difference ◽  
Diamondback Rattlesnake ◽  
Putative Toxin

The same selective forces that give rise to rapid inter- and intraspecific divergence in snake venoms can also favor differences in venoms across life-history stages. Ontogenetic changes in venom composition are well known and widespread in snakes but have not been investigated to the level of unambiguously identifying the specific loci involved. The eastern diamondback rattlesnake was previously shown to undergo an ontogenetic shift in venom composition at sexual maturity, and this shift accounted for more venom variation than geography. To characterize the genetics underlying the ontogenetic venom compositional change in C. adamanteus, we sequenced adult/juvenile pairs of venom-gland transcriptomes from five populations previously shown to have different adult venom compositions. We identified a total of 59 putative toxin transcripts for C. adamanteus, and 12 of these were involved in the ontogenetic change. Three toxins were downregulated, and nine were upregulated in adults relative to juveniles. Adults and juveniles expressed similar total levels of snake-venom metalloproteinases but differed substantially in their featured paralogs, and adults expressed higher levels of Bradykinin-potentiating and C-type natriuretic peptides, nerve growth factor, and specific paralogs of phospholipases A2 and snake venom serine proteinases. Juvenile venom was more toxic to mice, indicating that the expression differences resulted in a phenotypically, and therefore potentially ecologically, significant difference in venom function. We also showed that adult and juvenile venom-gland transcriptomes for a species with known ontogenetic venom variation were equally effective at individually providing a full characterization of the venom genes of a species but that any particular individual was likely to lack several toxins in their transcriptome. A full characterization of a species’ venom-gene complement therefore requires sequencing more than one individual, although the ages of the individuals are unimportant.

Understanding Process Variables and their Interactions for Maximizing Production of Artemisinin Derivative Artemether (Anti-Malarial Drug) Through Cunninghamella echinulata var elegans at 5 L Bioreactor Level

2019 ◽  
Vol 15 (4) ◽  
pp. 442-452
Author(s):  
Kashyap Kumar Dubey ◽  
Punit Kumar
Keyword(s):  
Experimental Finding ◽  
Culture Broth ◽  
Quadratic Model ◽  
Optimum Conditions ◽  
Reverse Phase Hplc ◽  
Polar Solvents ◽  
Reverse Phase ◽  
Experimental Conditions ◽  
Cunninghamella Echinulata ◽  
Life Threatening

Background: Malaria is one of the life threatening diseases which is caused by Plasmodium sp. of protozoa and uses Anopheles mosquitos as vector. Plasmodium vivax and Plasmodium falciparum are common form of malaria parasite. Artemisinin is reported for its antimalarial activities and Artemether which is a methyl ether derivative of Artemisinin, has been found effective against P. falciparum. Methods: In the present study, bioconversion of Artemisinin into Artemether was carried out experimentally and the statistical tools like experimental factorial design and Response Surface Methodology were used to find optimal conditions (concentration of Artemisinin, age of inoculum, temperature & pH) using Cunninghamella echinulata var. elegans. Experimental conditions for maximum product recovery from culture broth were also optimized using various polar and non-polar solvents for extraction. Artemether purity was analyzed by reverse-phase HPLC. Experimental data was fitted in a quadratic model and effect of various parameters was analyzed. Results: It was found that bioconversion of Artemisinin into Artemether is growth associated process. It was observed that molasses used as carbon source supported production of Artemether to 3.4g/L. The biomass and oxygen are key element affecting of bioconversion of Artemisinin into Artemether such as higher dissolved oxygen reduced the Artemether bioconversion. The highest bioconversion of Artemisinin into Artemether was obtained at temperature 25.5oC, 5g/L concentration of Artemisinin, at age of inoculum of 44.5 h and at pH 6.0. Model suggested the highest bioconversion of Artemisinin into Artemether was 54% at shake flask level which was near about experimental finding. An optimal condition for bioconversion was also analyzed and 64% bioconversion was obtained in 5L bioreactor. Conclusion: The outcomes of the study provided optimum conditions for bioconversion of Artemisinin into Artemether.

scholarly journals Orphan Designation and Cisplatin/Hyaluronan Complex in an Intracavitary Film for Malignant Mesothelioma

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 362
Author(s):  
Sabrina Banella ◽  
Eride Quarta ◽  
Paolo Colombo ◽  
Fabio Sonvico ◽  
Antonella Pagnoni ◽  
...  
Keyword(s):  
Sodium Hyaluronate ◽  
Chloride Ions ◽  
Complete Resection ◽  
Size Exclusion ◽  
European Medicines Agency ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Pharmaceutical Development ◽  
Film Forming ◽  
Exclusion Chromatography

Pleural mesothelioma is a lung diffuse tumor, whose complete resection is unlikely. Consequently, metastases reappear where the primary tumor was removed. This paper illustrates the orphan medicine designation procedure of an intracavitary cisplatin film and related pharmaceutical development aspects requested by the European Medicines Agency (EMA) in its Scientific Advice. Since cisplatin pharmacokinetics from the implanted film in sheep resulted substantially modified compared to intravenous administration, the formation of a cisplatin/hyaluronan complex had been hypothesized. Here, the interaction between sodium hyaluronate (NaHA) and cisplatin (CisPt) was demonstrated. Size exclusion chromatography qualitatively evidenced the complex in the film-forming mixture, only showing the NaHA peak. Atomic absorption spectroscopy of the corresponding fraction revealed platinum, confirming the interaction. Reverse phase HPLC quantified about 5% free cisplatin in the film-forming mixture, indirectly meaning that 95% was complexed. Finally, a study of CisPt release from the film assessed how CisPt/NaHA complex affected drug availability. In water, a medium without chloride ions, there was no release and the film remained intact for 48 h and longer, whereas the placebo film dissolved in 15 min. In 0.9% NaCl medium, the film became more soluble, dissolving within 3–4 h. However, cisplatin release was still controlled by the existing complex in solution until chloride ions displaced it. While the film modified its dissolution with aging, CisPt release remained unaffected (90% released in 48 h).

Quantitation of Amiodarone and Desethylamiodarone from Blood Serum and Myocardium Using Reverse Phase HPLC

1987 ◽  
Vol 10 (12) ◽  
pp. 2625-2637 ◽  
Author(s):  
J. Alan Menius ◽  
D. James Schumacher ◽  
Emily A. Hull-ryde ◽  
Cyril Y. Leung ◽  
Robin G. Cummings ◽  
...  
Keyword(s):  
Blood Serum ◽  
Reverse Phase Hplc ◽  
Reverse Phase

In vitro 19-norandrogen synthesis by equine placenta requires the participation of aromatase

1995 ◽  
Vol 144 (3) ◽  
pp. 517-525 ◽  
Author(s):  
S Moslemi ◽  
P Silberzahn ◽  
J-L Gaillard
Keyword(s):  
Silica Gel ◽  
Aromatase Inhibitors ◽  
Column Chromatography ◽  
Microsomal Fraction ◽  
Specific Activity ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Term Placenta ◽  
Flow Detector

Abstract Explants of equine full-term placenta have been shown to synthesize 19-norandrogens from labelled androgens. Steroid metabolites were purified by silica-gel column chromatography then analysed and quantified by C18-reverse-phase HPLC coupled to a radioactive flow detector. 19-Norandrostenedione was subsequently recrystallized to constant specific activity, providing unequivocal evidence of its synthesis by the equine placenta. 19-Norandrostenedione synthesis appeared to be localized in the microsomal fraction. Regardless of the substrate used, formation of 19-norandrogens was far weaker than that of oestrogens; moreover, the yield of 17-oxosteroids produced was much greater than that of 17β-hydroxysteroids, suggesting the presence of a dehydrogenase with predominant oxidative activity. Sulphoconjugated steroids formed were less than 0·5% of total steroids. Although 19-nortestosterone could not be generated by equine purified aromatase incubated with labelled testosterone, the synthesis of 19-norandrogens and oestrogens by equine placental explants was blocked by two specific aromatase inhibitors, 4-hydroxyandrostenedione and fadrozole. Our results provide evidence for a placental origin of at least a part of the 19-norandrogens previously identified in the blood of the pregnant mare. Furthermore, it is suggested that 19-norandrogen biosynthesis would involve the enzymatic metabolism of 19-oxygenated androgens formed by equine aromatase. Journal of Endocrinology (1995) 144, 517–525

scholarly journals RP-HPLC Determination of Raloxifene in Pharmaceuticl Tablets

2006 ◽  
Vol 3 (1) ◽  
pp. 60-64 ◽  
Author(s):  
P. Venkata Reddy ◽  
B. Sudha Rani ◽  
G. Srinu Babu ◽  
J. V. L. N. Seshagiri Rao
Keyword(s):  
Flow Rate ◽  
Retention Time ◽  
Mobile Phase ◽  
Dosage Forms ◽  
Hplc Method ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Pharmaceutical Dosage Forms ◽  
Rp Hplc

A reverse phase HPLC method is developed for the determination of Raloxifene in pharmaceutical dosage forms. Chromatography was carried out on an inertsil C18 column using a mixture of acetonitrile and phosphate buffer (30:70 v/v) as the mobile phase at a flow rate of 1 mL/min. Detection was carried out at 290 nm .The retention time of the drug was 10.609 min. The method produced linear responses in the concentration range of 0.5-200 µg/mL of Raloxifene. The method was found to be applicable for determination of the drug in tablets.

Sign in / Sign up

Export Citation Format

Share Document