Toad

About: Toad is a research topic. Over the lifetime, 1624 publications have been published within this topic receiving 28732 citations.

Failure of cholera enterotoxin to alter cyclic 3',5'-adenosine monophosphate-mediated responses in toad urinary bladder.

Abstract: Cholera enterotoxin, which stimulates mammalian adenyl cyclase, failed to affect cyclic 3,5'-adenosine monophosphate-mediated functions in toad bladder. In addition, cyclase-mediated responsiveness to vasopressin was maintained.

Novel Indole derivative as first P-glycoprotein inhibitor from the skin of Indian toad (Bufo melanostictus)

Abstract: Objective: To study the inhibitory effect of Novel Indole Derivative (NID) from Indian toad skin (Bufo melanostictus) on P-glycoprotein. Materials and methods: Dried Indian Toad skin was used to isolate NID with column chromatography, and its structure was elucidated by IR Spectra, 13C NMR, 1H NMR Spectra, and LC-MS. Female Wistar rats were used to determine LD50, In vitro permeability studies were done with the intestinal sac method, and In vivo pharmacokinetic studies were carried out to prove P-gp inhibition using the rat model. Results: The NID has shown increased apparent permeability Papp(x10-6cm/sec) significantly (p<0.001) from 1.04±0.11 to 2.90±0.08 in ileum 1.44±0.14 to 3.92±0.13 in jejunum this in vitro results confirmed that P-gp inhibited, this was further confirmed by in vivo studies and found to observe the increased oral bioavailability of digoxin significantly in NID treated groups from 3.26±0.25 to 7.47±0.18 ng/mL, the volume of distribution decreased from 232.56±64.59 to 86.57±7.04 L/kg. AUC increased from 37.89±1.13 to 64.62±0.70 ng/mL/hr. This demonstrates NID increased the oral bioavailability of digoxin significantly. Conclusion: Many compounds were isolated from Indian toad skin. This NID was not reported earlier. Results demonstrate NID increased the oral bioavailability of digoxin significantly. The isolated NID from Indian toad skin proved as a potent P-gp inhibitor in both in vitro and in vivo studies, and further studies needed to develop as a possible new drug candidate.

eDNA Metabarcoding Benchmarked towards Conventional Survey Methods in Amphibian Monitoring

Abstract: Simple Summary Amphibian species are declining worldwide, and precise monitoring is key to ensuring timely protection and thereby ceasing deteriorating populations. Conventional monitoring methods are invasive, time-consuming, and dependent on expert knowledge. eDNA methods have been suggested as a replacement for or supplement to conventional survey methods. The present study assessed amphibian detection of conventional survey methods and eDNA metabarcoding in Danish lakes and ponds to address how the application of eDNA surveys can supplement the currently applied methodology. The study found eDNA metabarcoding to detect five out of six species detected through conventional methods. Furthermore, it is expected that the results in the present study reflect the time of sampling for the applied methods. The findings in the present study indicate that eDNA metabarcoding detects multiple Danish amphibian species and can produce knowledge on the occurrence and distribution for amphibian species. Implementing it as a supplement for conventional survey methods in nature monitoring will enable a higher frequency of monitoring and yield knowledge of species composition. Abstract A keystone in protection work is accurate and thorough the monitoring of amphibian species, and the currently applied conventional survey methods are invasive, time-consuming, and dependent on expert knowledge. Research suggests that eDNA metabarcoding is a precise and cost-efficient method that could supplement the currently applied methods. The present study assessed the efficiency of conventional survey methods and eDNA metabarcoding in terms of species richness, the average number of detected species per site, the relative frequency of species occurrence, and the similarity of applied methods. The study found eDNA metabarcoding surveys to detect Lissotriton vulgaris (smooth newt), Triturus cristatus (great crested newt), Rana arvalis (moor frog), Rana temporaria (common frog), and Bufo bufo (common toad), as well as an average of 0.9 species per site, reflecting the species composition at the time of sampling in mid-July 2020. In addition to the species mentioned above, the conventional survey detected Epidalea calamita (natterjack toad) and an average of 1.7 species per site, reflecting the species composition at the time of sampling in early June 2020. The similarity between the methods applied in the present study was 27%, thus indicating a large number of unique observations of both eDNA metabarcoding and conventional surveys. The differences in detection can most likely be explained by the time of sampling, which was conducted a month apart. eDNA metabarcoding was efficient in detecting multiple amphibian species and produced unique observations that were not detected using conventional survey methods. Applying eDNA techniques as a supplement will most likely produce important knowledge on species distribution and presence, as well as enable more frequent monitoring due to cost efficiency and disturbance.

Characterizing Tissue Enzyme Activities in the Marine Toad (Rhinella marina)

Abstract: Plasma biochemistry tests are routine diagnostic tools in veterinary medicine that require an understanding of the enzyme activity profiles of individual organs for accurate interpretation. Tissue enzyme activity has been found to vary among and within taxa and has not been described in the marine toad (Rhinella marina). This study measured enzyme activities in the plasma, liver, heart, skeletal muscle, gastrointestinal system, kidney, and pancreas of five marine toads, to evaluate the tissue specificity of analytes commonly included on plasma biochemical analysis. In the marine toad, alanine transaminase (ALT) and aspartate transaminase activities were not specific to one organ, with minimal ALT activity measured in any organ tissue. Alkaline phosphatase activity was significantly higher in heart tissues and gamma-glutamyltransferase (GGT) activity was significantly higher in pancreatic tissues than in all other organ tissues, and plasma. GGT activity in the kidney was also significantly higher than that found in plasma, but not all other tissues. Amylase and lipase were highest in the plasma. Creatine phosphokinase and lactate dehydrogenase (LDH) were specific to skeletal muscle, with significant LDH activity also found in cardiac tissue. This information will be vital to the interpretation of plasma biochemistry analysis in the marine toad and shows similarities to tissue enzyme activity in the Cuban treefrog (Osteopilus septentrionalis), suggesting extrapolation to other anurans is possible.