31 research outputs found
Corpuscles of Stannius of freshwater mud eel, Amphipnous cuchia
O presente artigo estuda o número, localização e estrutura citológica dos corpúsculos de Stannius da enguia, Amphipnous cuchia. Nos corpúsculos de Stannius foram encontrados dois tipos celulares, células AF positivas e células AF negativas
Morphological modifications of corpuscles of Stannius of freshwater mud eel, Amphipnous cuchia in response to calcium: rich medium
Os corpúsculos de Stannius de Amphipnous ouchia após tratamento com cloreto de cálcio 0.8% mostram perda de conteúdo citoplasmático, células binucleadas e em degeneração
Effects of chlorpyrifos on ultimobranchial and parathyroid glands of Indian skipper frog, Euphlyctis cyanophlyctis
This study investigated effects of chlorpyrifos on ultimobranchial (UBG) and parathyroid glands (PTG) of frog, Euphlyctis cyanophlyctis. Frogs were treated with chlorpyrifos for short and long term and sacrificed after 24, 48, 72 or 96 h in short term and after 5.10, 15 and 30 days in long term. Chlorpyrifos exposure provokes decrease in serum calcium levels after 48 h which persists till 96 h. There is slight decrease in the nuclear volume of UBG cells and cytoplasm depict weak staining response after 72 h. After 96 h these changes are more pronounced. PTG of Euphlyctis cyanophlyctis exposed to chlorpyrifos exhibit no change till 96 h. Serum calcium decreases on day 10 after chlorpyrifos exposure which continue to fall progressively till 30 days. After 15 days chloryrifos exposure, nuclear volume of UBG exhibit decrease and follicular epithelium displays decrease in height. Follicular epithelium after 30 days chlorpyrifos exposure reduces to the extent that it becomes single layered. Few degenerating cells have been discerned. At this interval nuclear volume of ultimobranchial cells exhibits a further decrease. PTG of chlorpyrifos treated frog depicts increased nuclear volume of PTG at 10 and 15 days. The nuclei of PTG are hyperchromatic and the gland becomes compact at 15 days. After 30 days following chlorpyrifos treatment nuclear volume exhibits further increase. Also degenerating cells make their appearance. Calcium regulating glands UBG and PTG of frogs were adversely affected by exposure to chlorpyrifos which may disturb the physiological functions of the organism.
DOI: http://dx.doi.org/10.5281/zenodo.400415
Jamun seed and orange peel extracts protects effects of microcystin LR on serum calcium and phosphate of rats
Wistar rats were treated as Group A: Control; Group B: microcystin LR (MCLR); Group C: microcystin LR and jamun seed extract (MCLR+JSE); Group D: microcystin LR and orange peel extract (MCLR+OPE); Group E: orange peel extract (OPE); Group F: jamun seed extract (JSE). MCLR dose was 10 µg/kg body wt/day whereas OPE and JSE dose was 200 mg/kg body wt/day. Serum calcium and phosphate were analyzed on 15 and 30 day. Serum calcium of rat exposed for 15 day to MCLR; MCLR+JSE and MCLR+OPE decreased. Although there is little increase in levels of group C and group D but treatment with OPE and JSE is not able to completely restore decreased calcium levels caused by MCLR. After 30 day calcium decreased after MCLR; MCLR+JSE and MCLR+OPE treatment. Levels in group E and F remain unaltered. Levels in group C and D exhibit elevation as compared to group B which indicates that treatment with OPE and JSE recovered calcium. Serum phosphate decreased after 15 day in MCLR; MCLR+JSE and MCLR+OPE treated rats. Phosphate levels of group C (compared with group F) and group D (compared with group E) show decrease. After 30 day exposure to MCLR; MCLR+JSE and MCLR+OPE phosphate levels decreased. Levels of group C and D when compared with group B are increased. Phosphate levels of group C (compared with group F) and D (compared with group E) are decreased. This indicates that OPE and JSE treatment provoked some recovery of phosphate levels.
DOI: http://dx.doi.org/10.5281/zenodo.394065
High Fasting Insulin Levels and Insulin Resistance May Be Linked to Idiopathic Recurrent Pregnancy Loss: A Case-Control Study
Objective. Patients with more than two spontaneous pregnancy losses are diagnosed with recurrent pregnancy loss. The aim of this study was to evaluate the IR (insulin resistance) in patients with idiopathic recurrent pregnancy loss. Material and Method. A single center, case control study was performed on one hundred eighteen women divided into case group (with at least two pregnancy losses, earlier than 20 weeks of gestation, and negative for the recurrent pregnancy loss testing) and control group (with at least one live birth, no pregnancy loss). FG (fasting glucose) and FI (fasting insulin) were determined for all patients. IR was evaluated by HOMA-IR index. Results. There were not significant differences between the mean age and BMI in cases and controls ( > 0.05). Fasting glucose was significantly higher in the control group (85.6 versus 79.8 < 0.01), but fasting insulin (15.24 versus 12.83, < 0.001) and HOMA-IR (2.98 versus 2.69, < 0.05) were significantly higher in the case group. Conclusion. In women with idiopathic recurrent pregnancy loss FI and IR are higher than those in women without spontaneous abortion
Sodium fluoride induces hypercalcemia resulting from the upregulation of both osteoblastic and osteoclastic activities in goldfish, Carassius auratus
The influence of sodium fluoride (NaF) on calcium metabolism was examined in goldfish (fresh water teleost). At 2 days after administration of NaF (500 ng/g body weight; 5 μg/g body weight) (around 10− 5 to 10− 4 M in goldfish), we indicated that plasma calcium levels upregulated in both doses of NaF-treated goldfish. To examine the mechanism of hypercalcemia by NaF treatments, therefore, direct effects of NaF on osteoblasts and osteoclasts in goldfish were investigated by an original assay system using teleost scale which has osteoblasts, osteoclasts and bone matrix. Alkaline phosphatase activity in the scales increased with the treatment of NaF (10− 6 and 10− 5 M) during 6 h of incubation. Also, tartrate-resistant acid phosphatase activity increased after exposure to NaF (10− 5 M) at the 6 h of incubation. To investigate the osteoclastic activation, the mRNA expression of osteoclastogenesis related factors were examined. The receptor activator of the nuclear factor-κB ligand (RANKL) which is known as a factor for osteoclastogenesis, increased in the NaF-treated scales after 6 h of incubation. The ratio of RANKL/osteoprotegerin (osteoclastogenesis inhibitory factor) significantly increased after 6 h of incubation. Resulting from the increase of RANKL mRNA level, the expression of transcription-regulating factors was significantly increased. Furthermore, the expression of functional genes, cathepsin K and matrix metalloproteinase-9 mRNA, was significantly increased. In our knowledge, this is the first report concerning the effects of NaF on osteoblasts and osteoclasts in teleosts. We concluded that NaF influences calcium metabolism via osteoclastic activation in goldfish. © 2016 Elsevier Inc.Embargo Period 12 month
Acute Toxicity of a Heavy Metal Cadmium to an Anuran, the Indian Skipper Frog Rana cyanophlyctis
Background: There has been increasing awareness throughout the world regarding the remarkable decrease in amphibian population. For such amphibian population decline several causes have been given. Cadmium, a heavy metal is released both from natural sources (leaching of cadmium rich soils) and anthropogenic activities to the aquatic and terrestrial environments. This study evaluated the toxicity of heavy metal cadmium to Indian skipper frog Rana cyanophlyctis.
Methods: For the determination of LC50 values for cadmium, four-day static renewal acute toxicity test was used. Five replicates each containing ten frogs were subjected to each concentration of cadmium chloride (15, 20, 25, 30, 35, 40, 45 and 50 mg/L). At different exposure periods (24, 48, 72 and 96 h), the mortality of the frog was subjected to Probit analysis with the POLO-PC software (LeOra Software) to calculate the LC50 and 95% confidence level.
Results: The LC50 values of cadmium chloride for the frog R. cyanophlyctis at 24, 48, 72, and 96 h are 32.586, 29.994, 27.219 and 23.048 mg/L, respectively. The results have been discussed with the toxicity reported for other aquatic vertebrate --fish.
Conclusion: Cadmium caused mortality to the frog and this could be one of the reasons for population decline of frogs which inhabit water contaminated with heavy metals
Alterations in the Corpuscles of Stannius of Euphorbia royleana Treated Catfish, Heteropneustes fossilis
Background: We aimed to evaluate effect of Euphorbia royleana exposure on histocytology of corpuscles of Stannius in fish, Heteropneustes fossilis.
Methods: Fish were subjected to 2.47 mg/L and 0.618 mg/L of E. royleana for short-term and long-term exposure, respectively. Blood samples were collected on 24, 48, 72 and 96 h in short-term and after 7, 14, 21, and 28 d in long-term experiment and analyzed for serum calcium levels. Corpuscles of Stannius were fixed on these intervals.
Results: Serum calcium levels of H. fossilis decline progressively from 48 h until 96 h following the E. royleana exposures. Serum calcium levels decreased on 7 d. This decrease continued until close of the experiment. After 96 h treatment, AF–positive cells of CS exhibit increased granulation. Nuclear volume of these cells exhibited no change throughout short-term treatment. Increased nuclear volume of AF– negative cells of CS is noticed at 96 h. Nuclear volume of AF-positive cells decreases after 14 d and onwards. The AF–positive cells exhibit increased granulation following 21 d exposure. After 28 d these changes are intensified and few degenerating cells have been encountered. AF–negative cells of CS increase in their nuclear volume 21 d onwards.
Conclusion: The botanical pesticide induced severe changes in the corpuscles of Stannius of catfish. This gland controls the calcium level in fish and thus the use of E. royleana should not be done near water reservoirs
Acute Toxicity of an Organophosphate Insecticide Chlorpyrifos to an Anuran, Rana cyanophlyctis
Background: Chlorpyrifos is an organophosphate pesticide that elicits broad-spectrum insecticidal activity against a number of important arthropod pests. Determining the insecticides’ toxicity to amphibians can give us a better understanding regarding the role of toxicants in amphibian declines. This information would be beneficial to assess their ecological relevance at environmental concentrations. The present study assessed toxicity of chlorpyrifos to an anuran Rana cyanophlyctis.
Methods: For the determination of LC50 values for chlorpyrifos, four-day static renewal acute toxicity test was used. Five replicates each containing ten frogs were subjected to each concentration of chlorpyrifos (2, 4, 6, 8, 10, 12, 14 and 16 mg/L) for the test. Mortality of the frog at different exposure periods (24, 48, 72 and 96 h) was subjected to Probit analysis with the POLO-PC software (LeOra Software) to calculate the LC50 and 95% confidence level.
Results: The LC50 values of chlorpyrifos for the frog R. cyanophlyctis at 24, 48, 72, and 96 h were 8.252, 7.254, 6.247 and 4.993mg/L, respectively.
Conclusion: Mortality has been noticed in chlorpyrifos treated frogs related to the decline in amphibian population. Therefore, chlorpyrifos should not be used near water reservoirs