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Häidkind R Eller M Kask A Harro M Rinken A Oreland L Harro J 《Neurochemistry international》2004,45(5):721-732
The present study aimed at characterizing the effect of partial 5-HT denervation by parachloroamphetamine (PCA), a 5-HT selective neurotoxin, on forced swimming behaviour and monoamine levels in several rat brain regions. PCA was administered intraperitoneally in two independent experiments in doses of 2, 4 and 6 mg/kg and in doses 1, 2, 4 mg/kg, respectively. PCA (2 mg/kg) reduced immobility in the forced swimming test in the Experiment 1 and according to Experiment 2 this is explained by increased swimming time. Dose-dependent reductions in 5-HT and 5-HIAA levels were found in all brain regions studied, and the maximal effects were of a similar magnitude. In septum, the effect of PCA took more time to develop. The effects of the lowest dose of PCA suggest that the neurotoxin affects not only the dorsal raphe projection areas but also the fine axons which arise from the median raphe. alpha2-Adrenoceptors and beta-adrenoceptors in cerebral cortex were not affected by the PCA treatment. Binding affinity of the 5-HT(1A) receptors was higher after all doses of PCA. On the second exposure to the forced swimming the time spent in swimming was found to be negatively and the time spent in immobile posture positively correlated with serotonin turnover in frontal cortex. The time spent in struggling on the second exposure to test was found to be negatively correlated with KD of beta-adrenoceptor binding in cerebral cortex. These data suggest that partial 5-HT denervation with low doses of PCA, which elicits a specific pattern of neurodegeneration, results in an increased behavioural activity, and that the traditional interpretation of the measures in forced swimming test, despite of the test's predictive power in revealing antidepressants acting on monoaminergic systems, is not adequate for studies on the neurochemical basis of depression. 相似文献
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Saal K Sammelselg V Lõhmus A Kuusk E Raidaru G Rinken T Rinken A 《Biomolecular engineering》2002,19(2-6):195-199
Glucose oxidase (E.C 1.1.3.4) immobilized onto activated surface of mica was analyzed by enzymatic kinetics and visualization with atomic force microscopy (AFM). The activity of the immobilized enzyme decreased with the decrease of concentration of gamma-aminopropyltrimethoxysilane used for the first step of activation of mica, while AFM analysis showed similar homogeneous filling of the surface with the enzyme. The comparison of enzyme activity with its surface filling revealed that there has to be additional vertical structures, which cannot be visualized by the methods of AFM. The simultaneous decrease of the silanizing agent and the concentration of the enzyme led to molecular resolution for the enzyme on the surface of mica. This allows to propose the described method also for analyzing other surfaces of solid materials with coupled biomolecules. 相似文献
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Scheler O Kindt JT Qavi AJ Kaplinski L Glynn B Barry T Kurg A Bailey RC 《Biosensors & bioelectronics》2012,32(1):56-61
This work describes the development of an automated flow-based biosensor that employs genetically modified acetylcholinesterase (AChE) enzymes B394, B4 and wild type B131. The biosensor was based on a screen printed carbon electrode (SPE) that was integrated into a flow cell. Enzymes were immobilised on cobalt (II) phthalocyanine (CoPC) modified electrodes by entrapment in a photocrosslinkable polymer (PVA-AWP). The automated flow-based biosensor was successfully used to quantify three organophosphate pesticides (OPs) in milk samples. The OPs used were chlorpyriphos-oxon (CPO), ethyl paraoxon (EPOx) and malaoxon (MOx). The total analysis time for the assay was less than 15 min. Initially, the biosensor performance was tested in phosphate buffer solution (PBS) using B394, B131 and B4 biosensors. The best detection limits were obtained with B394; therefore, this biosensor was used to produce calibration data in milk with three OPs in the concentration range of 5 × 10(-6)M to 5 × 10(-12)M. The limit of detection (LOD) obtained in milk for CPO, EPOx and MOx were 5 × 10(-12)M, 5 × 10(-9)M and 5 × 10(-10)M, respectively, with a correlation coefficient R(2)=0.9910. The automated flow-based biosensor successfully quantified the OPs in different fat-containing milk samples. There were no false positives or false negatives observed for the analytical figures of merit for the constructed biosensors. This method is inexpensive, sensitive, portable, non-invasive and provides real-time results. This analytical system can provide rapid detection of highly toxic OPs in food matrices such as milk. 相似文献
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Mikelsaar R Nelis M Kurg A Zilina O Korrovits P Rätsep R Väli M 《Journal of applied genetics》2012,53(1):93-97
We describe the first case of two chromosomal abnormalities, balanced reciprocal translocation t(5;13)(q33;q12.1) and a microduplication
in the region 9q31.1, in a man suffering from infertility and pollinosis. In the region 13q12.1 is located the TUBA3C (tubulin, alpha 3c) gene, which plays an important dynamic role in the motility of flagella. This case might support the
opinion that haploinsufficiency of the TUBA3C gene could be the cause of sperm immotility and abnormal sperm morphology, resulting in infertility in the patient. Single-nucleotide
polymorphism (SNP) array analysis revealed a novel 9q31.1 microduplication inherited from both parents, which contributes
to the genomic instability. 相似文献
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Choudhary R Palm-Leis A Scott RC Guleria RS Rachut E Baker KM Pan J 《American journal of physiology. Heart and circulatory physiology》2008,294(2):H633-H644
This study was designed to determine the effect of all-trans retinoic acid (RA) on the development of cardiac remodeling in a pressure overload rat model. Male Sprague-Dawley rats were subjected to sham operation and the aortic constriction procedure. A subgroup of sham control and aortic constricted rats were treated with RA for 5 mo after surgery. Pressure-overloaded rats showed significantly increased interstitial and perivascular fibrosis, heart weight-to-body weight ratio, and gene expression of atrial natriuretic peptide and brain natriuretic peptide. Echocardiographic analysis showed that pressure overload induced systolic and diastolic dysfunction, as evidenced by decreased fractional shortening, ejection fraction, stroke volume, and increased E-to-E(a) ratio and isovolumic relaxation time. RA treatment prevented the above changes in cardiac structure and function and hypertrophic gene expression in pressure-overloaded rats. RA restored the ratio of Bcl-2 to Bax, inhibited cleavage of caspase-3 and -9, and prevented the decreases in the levels of SOD-1 and SOD-2. Pressure overload-induced phosphorylation of ERK1/2, JNK, and p38 was inhibited by RA, via upregulation of mitogen-activated protein kinase phosphatase (MKP)-1 and MKP-2. The pressure overload-induced production of angiotensin II was inhibited by RA via upregulation of expression of angiotensin-converting enzyme (ACE)2 and through inhibition of the expression of cardiac and renal renin, angiotensinogen, ACE, and angiotensin type 1 receptor. Similar results were observed in cultured neonatal cardiomyocytes in response to static stretch. These results demonstrate that RA has a significant inhibitory effect on pressure overload-induced cardiac remodeling, through inhibition of the expression of renin-angiotensin system components. 相似文献
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Lauris Kaplinski Ott Scheler Sven Parkel Priit Palta Kadri Toome Ants Kurg Maido Remm 《BMC biotechnology》2010,10(1):34
Background
The hybridization of synthetic Streptococcus pneumoniae tmRNA on a detection microarray is slow at 34°C resulting in low signal intensities. 相似文献9.
Małgorzata E. Arlet Lynne A. Isbell Freerk Molleman Ants Kaasik Rebecca L. Chancellor Colin A. Chapman Raivo Mänd James R. Carey 《International journal of primatology》2014,35(2):476-490
Differences among females in infant survival can contribute substantially to variance in fitness. Infant survival is a product of external risk factors and investment by kin, especially the mother, and is thus closely tied with the evolution of behavior and life history. Here we present a 9-yr study (2004–2012) of infant survival and sex ratio relative to age and dominance ranks of mothers and the presence of immigrant males in a free-ranging population of gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We consider immigrant males because they are known to increase infant mortality in several other species. We found that infants of older mothers had higher survival than those of younger mothers but that high rank did not confer a significant benefit on infant survival. Female infants had higher survival than male infants. Young, low-ranking females had more male infants than young, high-ranking females, which had slightly more daughters, but this difference declined as females aged because low-ranking females had more daughters as they aged. With limited data, we found a significant relationship between the presence of male immigrants and infant mortality (falls and unexplained disappearances) to 18 mo. Our results suggest that infant survival in gray-cheeked mangabeys is most precarious when mothers must allocate energy to their own growth as well as to their infants, that sons of young mothers are at greatest risk, and that immigrant males can negatively affect infant survival. 相似文献
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Ott Scheler Barry Glynn Sven Parkel Priit Palta Kadri Toome Lauris Kaplinski Maido Remm Majella Maher Ants Kurg 《BMC biotechnology》2009,9(1):45-6