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1.
EEG activity was recorded in rats submitted to osmotic opening of the BBB by intracarotid mannitol infusion.This procedure produced an immediate short-lasting depression of the EEG and a tardive paroxysmal EEG activity. Both these phenomena were more relevant on the ipsilateral hemisphere. In some instances a tonico-clonic seizure was recorded.Pre-treatment with diazepam abolished the occurrence of the tardive EEG and behavioral modifications.In accord with previous findings, focal seizure activity is likely to be responsible for the metabolic abnormalities associated with osmotic opening of the BBB. This preparation therefore produces in the brain unphysiological states in respect to local metabolism and electrical function. 相似文献
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T Sampietro S Lenzi O Giampietro P Cecchetti A Masoni R Navalesi 《Clinical physiology and biochemistry》1987,5(1):49-56
We developed a simple isocratic high performance liquid chromatography (HPLC) method for the quantitative determination of 5-hydroxymethyl-2-furfuraldehyde (5-HMF) liberated by mild hydrolysis of small amounts of glycosyl proteins. The absorbance of hydrolysate components after HPLC separation was recorded at 280 nm. To detect substances possibly interfering with the 5-HMF peak we always recorded the ratio of the peak heights A280 nm/A254 nm which was a constant value of 4.4. For each sample the blank was obtained by reduction with NaBH4 before hydrolysis with oxalic acid 1 mol/l. The best NaBH4/protein ratio was found to be 4 mg/mg. With this method we measured the nonenzymatic glycosylation (glycation) as 5-HMF in samples with a protein concentration as low as 0.8 mg/ml. 5-HMF produced per milligram of protein was independent from protein concentration for a wide range (0.8-10 mg/ml). The mean coefficient of variation for within assay and between precision was 6.8 and 11.6%, respectively. The 5-HMF measured on plasma proteins from normal subjects (n = 7) was 0.16 +/- 0.04 nmol/mg. Protein from insulin-dependent diabetic patients was 0.31 +/- 0.07 nmol/mg. With this method we succeeded in detecting an excessive glycation of platelet membrane proteins in 13 type-I diabetic patients. 相似文献
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G C Agnoli R Borgatti M Cacciari S Dorigoni C Garutti E Ikonomu P Lenzi M Marinelli 《Bollettino della Società italiana di biologia sperimentale》1989,65(2):147-153
The renal function was studied by clearance (cl.) method during hypotonic polyuria (oral water load followed by 5% dextrose solution infusion) and successive relative antidiuresis induced by lysine-8-vasopressin (LVP) administration (5 microU in bolo followed by continuous infusion at a rate of 0.04 microU/min). Four 15 min and two 60 min clearance (cl.) periods were performed during hypotonic polyuria and antidiuresis, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm, CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary PGE2, 6-keto-PGF1 alpha and TxB2 concentrations were determined by RIA method. Fourteen healthy women submitted to a normal sodium and potassium daily intake were studied; in 6 of them paired studies in absence and in presence of indomethacin (100 mg, i.m.), respectively, were performed. LVP induced a significant reduction of creatinine cl., urinary flow rate and of prostanoid excretion. In hypotonic polyuria, indomethacin significantly reduced the creatinine cl. and the diuretic response to the water load; moreover the urinary PGE2 and 6-keto-PGF1 alpha excretions were significantly lower (85.6 +/- 1.9% and 37.7 +/- 3.2%) while the reduction of urinary TxB2 excretion was not significant (34.4 +/- 13%). Indomethacin did not affect significantly the LVP renal effects in normal potassium balance. 相似文献
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G C Agnoli R Borgatti M Cacciari C Garutti E Ikonomu P Lenzi M Marinelli 《Bollettino della Società italiana di biologia sperimentale》1989,65(4):329-335
The renal function has been evaluated by clearance (cl.) method during hypotonic polyuria and successive moderate antidiuresis induced by a low dose of lysine-8-vasopressin; four 15 min and two 60 min cl. periods were performed, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm, CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary concentrations of PGE2, 6-keto-PGF1 alpha (6KPGF) and TxB2 were measured by RIA. The study protocol was applied in normal potassium balance and experimental potassium balance (KD), both in absence and presence of indomethacin. In KD groups with a potassium cumulative deficit of 198.4 +/- 22.2 meq (D3; n = 6) during polyuria significant correlations are consistent with the hypothesis that the lower the plasma potassium concentration is the higher the urinary chloride excretion and the inhibition of distal fractional chloride reabsorption. Moreover, by utilizing the polyuria and antidiuresis data pool, the effects of urine flow rate changes on PGE2 and 6KPGF urinary excretions are blunted as compared to normal potassium balance (n = 14). After indomethacin treatment (D3.I) the following functional relationships are disclosed: a) the lower the kaliemia is the lower the urinary chloride and potassium excretions and the higher the fractional isosmotic reabsorption; b) the lower the urinary potassium excretion is the lower the urinary chloride excretion. In both D3 and D3.I experimental groups the positive correlation between urinary chloride excretion and urinary potassium excretion is significant. 相似文献
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Paula Tatiana Lopes Seixas Antonio Jacinto Demuner Luiz Claudio Almeida Barbosa Cristiane Isaac Cerceau Daiane Einhardt Blank Marcelo Henrique Dos Santos Elizeu de Sá Farias Marcelo Coutinho Picanço 《Journal of Applied Entomology》2023,147(2):116-125
Aedes aegypti L. (Diptera: Culicidae) is a vector for serious diseases in tropical regions. This pest is mainly controlled by commercial larvicides but the application of such products has led to environmental problems. Essential oils (EO) have been consistently reported as molecules with insecticidal activity and can be used to produce more environmentally friendly larvicides in the control of A. aegypti. In this study, the larvicidal effect of essential oils (EO) from the leaves of three Artemisia species was evaluated against A. aegypti. The oils were obtained from steam distillation and their chemical composition was determined by gas chromatography–mass spectrometry. The EO of Artemisia camphorata was the most active in the screening bioassay and presented LC50 and LC95 of 64.95 and 74.18 μg ml−1, respectively. In addition, we found that germacrene D-4-ol was the constituent responsible for the toxicity of this EO. Artemisia camphorata EO and its major constituent, germacrene D-4-ol, are promising for the development of natural larvicides against A. aegypti. 相似文献
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G C Agnoli R Borgatti M Cacciari S Dorigoni C Garutti E Ikonomu P Lenzi 《Bollettino della Società italiana di biologia sperimentale》1984,60(10):1943-1948
The renal function in healthy man with salt and water depletion induced by natriuretic treatment was explored during steady hypotonic polyuria. Four 15 min clearance (cl.) periods, before, during and after dopamine (DA) infusion in a subpressor dose were performed. The 12 examined subjects showed different renal hemodynamic responses in the early stage of DA infusion, i.e. hyperemic (4 subjects, subgroup A) or ischemic (8 subjects, subgroup B). A decrease in urinary sodium excretion and increase in tubular sodium reabsorption, in particular at the diluting segment level, were induced by DA in both subgroups, at least in the late stage of infusion. During the control cl. period in subgroup A as compared with B the renal plasma flow was lower and the tubular sodium reabsorption higher, suggesting a relatively higher level of renal adrenergic activity. 相似文献
10.
We have studied inflammatory reactions in the mesenteric tissue of mice infected with Schistosoma mansoni. Perivascular tissue contained diffuse infiltrates of macrophages, eosinophilic granulocytes and lymphocytes. Angiogenesis in the perivascular adipose tissue was associated with superficial plasmacytogenic foci. Polypoid structures were occasionally formed adjacent to inflammatory foci in the adipose tissue, organized around loops of capillaries, with terminal formation of a glomerular capillary network embedded in connective tissue, covered by plasmacytes. We conclude that these structures are specialized milky spots dedicated to active plasmacytogenesis and antibody secretion into the peritoneal cavity of schistosome-infected mice. 相似文献