The effects of zinc and copper salts on Cyprinus carpio and Ctenopharyngodon idellus

The effects of zinc and copper salts on the survival of the two species of freshwater fish, common carp, Cyprinus carpio, and grass carp, Ctenopharyngodon idellus, were investigated. It was discovered that the levels of tolerance to the concentration of the metals were species-specific. Cyprinus carpio was found to be more susceptible to copper, whereas Ctenopharyngodon idellus was more susceptible to zinc. In general, copper was more toxic than zinc, as revealed by the survival times. The body and the gills of dead fish seemed to be covered by a veil-like film which looked like coagulated mucus and which was formed by the heavy-metal ions reacting with some constituents of the mucus and which was formed by the heavy-metal ions reacting with some constituents of the mucus secreted by the gill. The histopathological assessment of the gill and liver of Cyprinus carpio was also carried out. Particles were observed around the gills of the dead fish treated with zinc and copper salts, although no other major changes were found in the gill. Several histopathological changes were observed in the livers, including the presence of particles. The symptoms of the liver suggested that the internal injury was also an important feature of the intoxicants.     

Effects of synthetic salmon calcitonin and alendronate on bone quality in ovariectomized rats

BACKGROUND: The aim of this study was to assess the effect of calcitonin (CCT) and alendronate (ALN) on bone quality through histomorphometric, histological, densitometric and crystallographic evaluations in an experimental model of osteoporosis obtained in ovariectomized rats. METHODS: The animals were randomly assigned to the treatment with CCT (2 IU/kg/day, N-12) or with ALN (6 micrograms/kg/day, N-12) given subcutaneously, starting three months after ovariectomy: treatment lasted 60 days. Six rats untreated after ovariectomy and other 6 non ovariectomized (intact) were taken as controls. At the end of treatment the animals were sacrificed and femurs explanted for laboratory examinations. Results were evaluated by an ANOVA followed by the Tukey's test when appropriate. RESULTS: The histomorphometric analysis showed a significant increase of the trabecular bone volume and of the cortical bone thickness either with CCT and ALN in comparison with the ovariectomized untreated controls. Optic and electronic microscopy examinations suggest a higher bone remodeling after ALN than after CCT, but accompanied by areas of imperfect mineralization, and more irregular osteon and collagen fibres disposition. The densitometry carried out at the femoral head and diaphysis showed a similar bone mass increase following either CCT and ALN, but significantly higher in comparison to the untreated controls. At the diaphysis level ALN was superior in increasing the bone mass also when compared to the intact rats. The mineralogic exams showed that CCT acted on the re-elaboration of the mineral phase approaching the molar ratio Ca/PO4 to the physiological values typical of senescence, and crystallography revealed that the formation of hydroxyapatite crystals follows a physiological mineral redeposition: those phenomena were not observed for ALN. CONCLUSIONS: In conclusion both CCT and ALN could reduce the bone loss due to osteoporosis, by increasing the bone mass and thickness. Nevertheless the submicroscopic and chemical bone structure are less similar to the physiologic ones after treatment with ALN.     

鄱阳湖鲤、鲫鱼资源变迁及其原因初探

[目的]保护和合理开发利用鄱阳湖鲤、鲫鱼资源.[方法]在分析1959-2006年鄱阳湖鲤、鲫鱼资源数据的基础上,分析近50年鄱阳湖鲤、鲫鱼资源变迁情况,并初步探讨了该变化的发生原因及相关应对措施.[ 结果]50来鄱阳湖鲤、鲫鱼虽成为优势种群,但其个体越来越小,性成熟年龄也越来越小,资源呈现出严重衰退状况.其原因主要是由于鄱阳湖枯水期水位过低,水质污染,加上过度捕捞以及非法渔具渔法的滥用等方面引起的.[结论]应明确鄱阳湖鲤、鲫鱼产卵场的范围,严格控制鄱阳湖流域工业污水、城市污水以及农业面污染源的直接排放.     

Microcalorimetric study of the toxic effect of selenium on the mitochondrial metabolism of Cyprinus carpio liver

Brief periods of global cerebral ischemia are known to produce characteristic patterns of neuronal injury both in human studies and in experimental animal models. Ischemic damage to vulnerable areas such as the CA1 sector of the hippocampus is thought to result from excitotoxic amino acid neurotransmission. The objective of this study was to determine the ability of a novel sodium channel blocking compound, zonisamide, to reduce neuronal damage by preventing the ischemia-associated accumulation of extracellular glutamate. Using a gerbil model, animals were subjected to 5 min ischemic insults. Both pre- and post-ischemic drug administration (zonisamide 150 mg/kg) were studied. Histological brain sections were prepared using a silver stain at 7 and 28 days post ischemia. The animals sacrificed at 28 days also underwent behavioral testing using a modified Morris water maze. In vivo microdialysis was performed on a separate group of animals in order to determine the patterns of ischemia-induced glutamate accumulation in the CA1 sector of the hippocampus. Pyramidal cell damage scores in the CA1 region of the hippocampus were significantly reduced in animals pre-treated with zonisamide compared to saline-treated controls, both at 7 days (drug pre-treated: 0.812 +/- 0.28, n = 8; controls: 1.625 +/- 0.24, n = 8; *P < 0.05) and 28 (drug pre-treated: 0.833 +/- 0.22, n = 12; controls: 1.955 +/- 0.26, n = 11; **P < 0.01) days post ischemia. However, animals receiving zonisamide post-treatment did not display significant differences from controls. Behavioral studies also showed significant preservation of function in drug-treated animals. Microdialysis studies confirmed a reduction in glutamate release in drug-treated animals compared to saline-treated controls. Our data suggest that zonisamide is effective in reducing neuronal damage by a mechanism involving decreased ischemia-induced extracellular glutamate accumulation and interruption of excitotoxic pathways.     

Release of proteins and polysaccharides from the albumen gland of the freshwater snail Helisoma duryi: effect of cAMP and brain extracts

The albumen gland is a compound tubular exocrine gland found in the female reproductive tract of freshwater pulmonate snails such as Helisoma duryi. It secretes a perivitelline fluid, composed of protein and polysaccharide complexes, and coats each fertilized egg. A 288-kDa native glycoprotein, composed of several 66-kDa subunits, was identified in soluble extracts of albumen gland. Forskolin stimulates the release of secretory granules, containing both proteins and polysaccharides, from the cytoplasm of the glandular cells. An acid extract of the central nervous system or the adenosine-3', 5'-cyclic monophosphate (cAMP) analogue 8-bromo cAMP, stimulates protein secretion from the gland. Pretreatment of the albumen gland with cAMP antagonist (Rp isomer of cAMP) inhibits the stimulatory effect of a brain extract. Digestion of brain extract with proteolytic enzymes abolishes its activity, suggesting the factor from the brain is peptidergic. The neuroactive agents serotonin, Phe-Met-Arg-Phe-amide, Tyr-Gly-Gly-Phe-Met-Arg-Phe-amide, small cardioactive peptide B, and caudodorsal cell hormone were also tested for potential secretion-promoting ability. Brain extracts were partially purified with a Sep-Pak C18 reverse-phase cartridge and indicate the peptide is relatively hydrophobic. These results suggest that a brain peptide promotes the secretion of perivitelline fluid, and this is mediated by the adenylate cyclase/cAMP signal transduction pathway.     

Effects of chelation on the bioconcentraton of cadmium and copper by carp (Cyprinus carpio L.)

The performance of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) and superparamagnetic iron oxide (SPIO) particles in detecting liver cancer was compared using alternative free-response receiver operating characteristic (AFROC) analysis, which allowed observers to indicate both the confidence level and the locations of all perceived abnormalities. Axial T1-weighted MR images (1.5 T) pre/post Gd-EOB-DTPA (25 mumol/kg) injection were obtained for 12 rats with chemically induced liver tumors (64 tumors). T2-weighted images (T2WI) were obtained pre/post SPIO (10 mumol/kg) injection for the same animal. Liver signal-to-noise ratio (SNR), tumor-liver contrast-to-noise ratio (CNR), and histopathologic sections corresponding to MR images were obtained. In AFROC, the location and the confidence level for each tumor were indicated independently on MR images by four radiologists. By plotting true-positive fraction and probability of false-positive per image, the area under the AFROC curve (A1) was estimated and statistically analyzed between each sequence. Either drug significantly improved tumor-liver CNR (P < .001) and tumor detection (diameter < or = 6 mm; P < .05). Gd-EOB-DTPA significantly (P < .05) improved the A1 in T1WI. There was no A1 difference between T2WI + SPIO and T1WI + Gd-EOB-DTPA. Gd-EOB-DTPA-enhanced T1WI showed the same performance as SPIO-enhanced T2WI in detecting liver tumors.     

Study of the endogenous calcitonin transport in the rat thyroid gland

Regression analysis revealed a significant correlation between Nvsq and calcitonine. The regression model was then transformed into a covariation one to establish: 1) probability of all calcitonine molecules moving across the C-cell-blood barrier into the blood, 2) confidence interval of endogenous calcitonine bioavailability, and 3) estimate of the period of calcitonine half-retention by the C-cell-blood barrier.     

Absorption of inorganic phosphate in the human jejunum and its inhibition by salmon calcitonin

The jejunal absorption of inorganic phosphate (P) was studied under basal conditions and during the intravenous infusion of synthetic salmon calcitonin (SCT) in normal subjects. Net P absorption increased as the intraluminal P concentration was raised. At intraluminal P concentrations equal to or above the plasma P level P absorption manifested first order kinetics. At intraluminal P concentrations below the plasma P level, net P absorption was non-linear presumably due to the movement of P from plasma to the lumen down a chemical gradient. A net secretion of water and electrolytes occurred in six normal subjects given SCT (250 ng/kg/hr) while saline infusion instead of SCT had no effect on jejunal absorption. Along with the secretory effect SCT reduced calcium and P absorption by 58% and 62% respectively, without any significant fall in the serum levels of calcium or P. The jejunal response to SCT was reproduced twice in a hypoparathyroid subject showing that endogenous parathyroid hormone was not involved in this effect. Calcium and P absorption were positively correlated with water movement suggesting that the observed changes in calcium and P absorption are due primarily to SCT-induced secretion of water. It is concluded that SCT induces a net secretion of water and ions while simultaneously reducing calcium and P absorption.     

Dimeric form of calcitonin gene-related peptide in the porcine thyroid gland

In this study we investigated peptides that increase rat platelet cAMP in porcine thyroid gland. Gel filtration of extracts from porcine thyroid gland showed high and low molecular weight activity. Low molecular weight activity contained peptides, including calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine (PHI). We isolated a high molecular weight peptide (M. W. 11,000) showing potent activity able to increase rat platelet cAMP in porcine thyroid gland. The peptide's N-terminal sequence was determined to be Ser-X-Asn-Thr-Ala-Thr- by gas phase sequencer analysis, a sequence identical to that of porcine CGRP. The peptide had CGRP immunoreactivity as well as platelet cAMP elevating activity. By gel filtration HPLC, synthetic human CGRP (M. W. 3790) was eluted in a position corresponding to M. W. 5,500. These results suggest that judging from its high molecular weight the above peptide is a dimeric form of CGRP.     

The effect of SDS, sodium dodecyl sulfate, on the metabolism and swimming capacity of Cyprinus carpio

Currently, diagnoses of attention deficit hyperactivity disorder (ADHD) and hyperkinetic disorder (HKD) are made on the basis of phenomenology, but information is accumulating from the neurosciences about the biological bases of these disorders. Recent studies addressing the neuropsychology, neuroanatomy, neurochemistry, and molecular biology of ADHD/HKD document abnormalities in well-defined neuroanatomical networks and neurochemical pathways. Magnetic resonance imaging (MRI) studies have shown that some regions of the frontal lobes (anterior superior and inferior) and basal ganglia (caudate nucleus and globus pallidus) are about 10% smaller in ADHD groups than in control groups of children, and molecular genetic studies have shown that diagnosis of ADHD is associated with polymorphisms in some dopamine genes (the dopamine D4 receptor gene and the dopamine transporter gene).     

Production of bioactive salmon calcitonin from the nonendocrine cell lines COS-7 and CHO

To produce bioactive salmon calcitonin from the conventional nonendocrine cell lines, COS-7 and CHO, we devised a salmon calcitonin expression vector by combining the amino-terminus of human calcitonin precursor with a salmon calcitonin sequence, inserting the efficient furin-cleavable processing sequence Arg-X-Arg-X-Lys-Arg before salmon calcitonin, and deleting the carboxyl-terminal extension peptide. This chimeric calcitonin precursor terminates at glycine to easily receive an amidation reaction. COS-7 and CHO produced a high level of bioactive calcitonin by the resorption pit formation assay. Although amidating activity is highly expressed in CHO, but only a little in COS-7 cells, both cells produced a similar level of bioactive calcitonin. Thus, the engineered salmon calcitonin expression vector enables nonendocrine cells even with low amidation activity to produce bioactive calcitonin.     

Role of the cytoskeleton in the secretory response of the frog adrenal gland to calcitonin gene-related peptide

We have previously shown that calcitonin gene-related peptide (CGRP) stimulates the secretion of corticosterone and aldosterone from the frog adrenal gland in vitro. The aim of the present study was to investigate the role of cytoskeletal elements in the stimulatory effect of CGRP on corticosteroid production. Perifusion of adrenal explants with the microfilament-disrupting agent cytochalasin B (5 x 10(-5) M) induced a reversible inhibition of the spontaneous secretion of corticosterone and aldosterone, and markedly reduced the stimulatory effect of frog CGRP (3 x 10(-7) M) on corticosteroid release. In contrast, administration of the antimicrotubular agent vinblastine (10(-5) M) and the intermediate filament inhibitor beta-beta' iminodipropionitrile (10(-3) M) had no significant effect on either spontaneous or CGRP-evoked steroid secretion. Taken together, these data provide the first evidence for the involvement of microfilaments in CGRP-induced corticosteroid secretion. In contrast, microtubules and intermediate filaments are not implicated in the mechanism of action of CGRP.     

Biological activities of mammalian and teleostean prolactins and growth hormones on mouse mammary gland and teleost urinary bladder

Using a two-lever food-reinforced operant procedure, rats (n = 10) were trained to discriminate 0.16 mg/kg dl-amphetamine from saline. Over the dose range 0.08 to 0.63 mg/kg, cue detection was found to be dose-dependent (ED50: 0.13 mg/kg). However, 5 mg/kg dl-amphetamine was not generalized with the standard treatment. Further generalization experiments indicated that hydroxyamphetamine (ED50: 0.16 mg/kg) produces a discriminative stimulus similar to that of 0.16 mg/kg dl-amphetamine. Apomorphine (0.16 mg/kg), chlordiazepoxide (10 mg/kg), desipramine (10 mg/kg), fentanyl (0.04 mg/kg), haloperidol (0.04 mg/kg) and isopropamide (0.04 mg/kg) were not generalized with dl-amphetamine. Haloperidol (0.04 to 0.16 mg/kg) blocked the perception of 0.16 mg/kg dl-amphetamine in a dose-related way (ED50: 0.092 mg/kg). It is concluded that the discriminative stimulus properties of low dl-amphetamine doses differ qualitatively from those of high doses. The discriminative stimulus produced by 0.16 mg/kg dl-amphetamine presumably originates peripherally, whereas that produced by high doses of the drug reportedly is of central origin.     

Inhibition by salmon calcitonin (SCT) of desoxycorticosterone acetate (DOCA) induced hypertension in the rat

Two cases of a continuous murmur following an acute pulmonary embolic episode are presented, and eight previously reported cases with an acquired postembolic continuous murmur (found in a review of the literature) are discussed. This finding is present in both chronic and acute pulmonary embolism and is suggestive of significant embolic obstruction. Although the continuous murmur is an unusual sign in patients with pulmonary embolism, its auscultation is often quite distinctive, and its appearance may lead to more definitive diagnostic studies when the presentation or associated clinical findings are nonspecific.