Effects of dp-B on ATPase activity of insect plasma membrane

Inhibition of ATPase from aphid plasma membrane, sarcoplasmic reticulum (SR), and brain synaptosomal plasma membrane of locust, by 1,5-diphenyl-2-penten-1-one (dp-B), was studied. Results demonstrated that dp-B exhibited the similar effects on ATPase found in the three membranes amongst which the plasma membrane Ca²⁺–Mg²⁺-ATPase is the primary target. The effects of dp-B on Ca²⁺–Mg²⁺-ATPase activity were bi-directional: the enzyme enhanced hydrolyzation when dp-B or Ca²⁺ concentrations were low but inhibited significantly when at high concentrations. The inhibition of Ca²⁺–Mg²⁺-ATPase by dp-B from brain synaptosomal plasma membrane of insect is higher than that from other organizational plasma membranes of the insect. Dp-B inhibiting Ca²⁺- and CaM-requiring ATPase activity may be an important mechanism by which the insect gets poisoned (for example aphid).     

Cerebrospinal fluid from a 10-year-old dog with a single seizure episode

A cerebrospinal fluid sample collected from the cerebellomedullary cistern of a 10-year-old Shetland Sheepdog with a recent history of seizures was submitted for fluid analysis and cytologic examination. Key findings included a total nucleated cell count of 520/microL (reference interval 0-5 cells/microL), with a predominance of mononuclear cells, a protein concentration of 51.8 mg/dL (reference interval 0-35 mg/dL), and a glucose concentration of 44.7 mg/dL (reference interval 52-105 mg/dL). There was marked atypia of the mononuclear cells, with abundant eosinophilic cytoplasm, marked anisocytosis and anisokaryosis, occasional binucleated cells, mitotic figures, and rare erythrophagia. The cytologic interpretation was marked, monocytoid-rich, mixed cell pleocytosis with cellular atypia worrisome for neoplasia. In addition to histiocytic neoplasia, differentials included granulomatous meningoencephalomyelitis, necrotizing meningoencephalitis, and granulomatous inflammation. The dog did not respond to anti-inflammatory and anticonvulsive therapy. At necropsy, a mass involving the meninges and subtending the neuropil of the right temporal lobe of the cerebrum was found. Histologically, the mass was composed of large, bizarre histiocytic cells with multinucleated forms and numerous mitotic figures. Using immunochemistry on cytologic and histologic samples, the pleomorphic histiocytic cells were positive for CD1c, CD11ad, CD45, lysozyme, and vimentin, and were negative for CD3, CD4, CD79a, CD90, and pancytokeratin. These findings supported a diagnosis of primary CNS malignant histiocytosis of dendritic antigen-presenting cell (CD1c+) origin. To our knowledge, this is only the third reported case of primary CNS histiocytic sarcoma in dogs, and the first to demonstrate strong immunochemical evidence for dendritic antigen-presenting cell origin.     

Applicability of a rapid chromatographic immunoassay for analysis of the distribution of PrPBSE in confirmed BSE cases

The Prionics-Check PrioSTRIP is a rapid chromatographic immunoassay for bovine spongiform encephalopathy (BSE) approved by the European Union in 2004. In this study, the PrioSTRIP was used to analyse PrP(BSE) in 16 different brain areas of nine confirmed BSE cases. The levels of PrP(BSE) in the different brain areas were plotted to give the brain PrP(BSE) distribution curve (BPDC) and compared with the BPDC obtained previously by Western blotting and enzyme-linked immunosorbent assay (ELISA) methods on the same samples. The distribution of PrP(BSE) in different areas of the brain was similar, irrespective of the test applied, indicating that each test could be used for the characterisation of BSE cases.     

Effect of BNP- mediated cAMP-PKA signaling pathway on bFGF expression in rats with spleen-qi deficiency syndrome

AIM: To explore the changes and the mechanism of heart functions in the rats with spleen-qi deficiency syndrome. METHODS: The rats were randomly divided into blank control group and spleen-qi deficiency model group. The changes of cardiac functions in the rats were determined by ultrasonic imaging with a high-resolution in vivo imaging system. HE staining was used to observe the pathological changes. The protein expression of brain natriuretic peptide (BNP) in the myocardium was assessed by Western blotting. The contents of BNP and cAMP in the serum and myocardium were measured by ELISA. The mRNA expression of basic fibroblast growth factor (bFGF) and protein kinase A (PKA) was detected by real-time PCR. RESULTS: Compared with blank control group, the myocardial cells in the model group had different degrees of necrosis and degeneration. Stroke volume and ejection fraction were decreased. The contents of cAMP and BNP in the serum and myocardium were increased in model group. The protein expression of BNP and the mRNA expression of bFGF and PKA were also increased.CONCLUSION: Spleen-qi deficiency syndrome causes heart function decline in rats. The expression of BNP, cAMP, PKA and bFGF is all increased.     

Changes of BAEP,NO contents and Na+-K+ATPase activities in brain tissues in rats with hyperbilirubinemia

AIM: To explore the roles of brain-stem auditory evoked potential (BAEP) in early monitoring the hearing loss and brain damages in hyperbilirubinemia and nitric oxide(NO) in the pathogenesis of bilirubin-induced hearing loss and brain damages. METHODS: Different doses of bilirubin solution (30 mg/kg, 60 mg/kg, 90 mg/kg, 120 mg/kg and 150 mg/kg) were injected into the abdominal cavity of 15-day old SD rats to make the animal model of hyperbilirubinemia. The serum concentrations of bilirubin were detected by a micro-gauge. The bilirubin concentrations in the brain tissues were examined via a diazo method. The Na+-K+ATPase activities in the brain tissues were analyzed by rooting phosphorus. The NO contents in the brain tissues were assayed via the method of nitrate reductase. BAEP were recorded with an evoked potential recorder. RESULTS: After making the ejection, parts of the rats in the high dosage groups (120 mg/kg and 150 mg/kg) showed the abnormal neuro-behaviors. After 6 hours of the ejection, the bilirubin concentrations in serum and in brain tissues, and NO contents in the brain tissues were increased significantly. The Na+-K+ATPase activities in the brain tissues were decreased obviously, and the PL and IPL of BAEP were prolonged significantly in all the experimental rats except the ones in low dosage group (30 mg/kg). The changes of them were closely related to the dose of injected bilirubin. CONCLUSION: The PL and IPL of BAEP are the objective and sensitive indexes for early monitoring the hearing loss and brain damages in hyperbilirubinemia. NO may plays a certain role in the pathogenesis of bilirubin induced hearing loss and brain damages.     

Upregulative effect of CGRP on expression of CREB and phospho-CREB protein during focal cerebral ischemia/reperfusion in rat parietal cortex

AIM: To investigate the effect of calcitonin gene related peptide (CGRP) on the expression of cyclic AMP response element binding protein (CREB) and phosphorylated-CREB in rat parietal cortex during focal cerebral ischemia/reperfusion (I/R).METHODS: Focal cerebral ischemia/reperfusion model was induced by occlusion of the right middle cerebral artery using the intraluminal suture method. The expressions of CREB and phospho-CREB in the parietal cortex in different groups (sham group, focal cerebral ischemia/reperfusion group and CGRP group) were detected with immunohistochemistry and Western blotting, and the positive products were analyzed by image analysis system.RESULTS: There was definite expression of CREB in right parietal cortex in sham group, while it was lesser in I/R group than that in sham group, but it became more in CGRP group than that in I/R group (P<0.05). Phospho-CREB was barely detected in right parietal cortex in sham group and it became more in I/R group than that in sham group. The expression of phospho-CREB increased in CGRP group than that in I/R group of the right parietal cortex (P<0.05).CONCLUSION: CGRP upregulates the expression of CREB and phospho-CREB in the ischemic neurons of the parietal cortex during focal cerebral ischemia/reperfusion and CREB probably involves in the mechanism of protective role of CGRP to ischemic neurons.