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21.
Semiquantitative detection by real-time PCR of Aspergillus fumigatus in bronchoalveolar lavage fluids and tissue biopsy specimens from patients with invasive aspergillosis 下载免费PDF全文
Rantakokko-Jalava K Laaksonen S Issakainen J Vauras J Nikoskelainen J Viljanen MK Salonen J 《Journal of clinical microbiology》2003,41(9):4304-4311
A real-time PCR method was developed and used to detect Aspergillus fumigatus mitochondrial DNA (mtDNA) in bronchoalveolar lavage (BAL) fluids and tissue biopsy specimens. The analytical sensitivity of the assay was one A. fumigatus conidium per reaction, and the assay was linear at least over 4 orders of magnitude above the detection limit. BAL fluids from 66 immunocompromised patients at risk of invasive pulmonary aspergillosis (IPA) and 33 immunocompetent controls and tissue biopsy specimens from 10 immunocompromised patients were analyzed. The results were related to the clinical diagnosis established according to recently published consensus criteria. A. fumigatus mtDNA positivity was encountered in 16 of 81 (20%) BAL fluid specimens from patients at risk and 1 of 33 (3%) specimens from immunocompetent controls. PCRs were positive in six of seven, two of four, and four of five of the patients with proven, probable, and possible IPA, respectively, as well as in four patients at risk but without any other evidence of IPA. With qualitative detection, the diagnostic sensitivity of PCR was 73%, specificity was 93%, and predictive values of positive (PPV) and negative (NPV) results were 73 and 95%, respectively. Using a threshold cycle of <35 as a limit for positive PCR, the specificity and PPV of PCR in the diagnosis of invasive aspergillosis were 100%, but its sensitivity was only 45% and NPV was 92%. PCR was positive in tissue biopsy specimens from all patients with invasive aspergillosis caused by A. fumigatus. Semiquantitative detection of A. fumigatus mtDNA in BAL fluid may be helpful in the diagnosis of IPA. PCR is well suited for the verification of the presence of A. fumigatus in tissue biopsy specimens. 相似文献
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Juha P Ahtiainen Arto Pakarinen William J Kraemer Keijo H?kkinen 《Revue canadienne de physiologie appliquée》2004,29(5):527-543
The aim of the present study was to investigate acute hormonal and neuromuscular responses and recovery in strength athletes versus nonathletes during heavy resistance exercise performed with the forced and maximum repetitions training protocol. Eight male strength athletes (SA) with several years of continuous resistance training experience and 8 physically active but non-strength athletes (NA) volunteered as subjects. The experimental design comprised two loading sessions: maximum repetitions (MR) and forced repetitions (FR). MR included 12-RM squats for 4 sets with a 2-min recovery between sets. In FR the initial load was higher than in MR so that the subject could lift approximately 8 repetitions by himself and 4 additional repetitions with assistance. Before and after the loading protocols, blood samples were drawn to determine serum testosterone, free testosterone, cortisol and growth hormone concentrations, and blood lactate. Maximal voluntary isometric force and EMG activity of the leg extensors was measured before and after the loading as well as 24 and 48 hrs after the loading. The concentrations of the hormones measured increased significantly (p < .01-.001) after both loadings in both groups. The responses tended to be higher in FR than the MR loading and the increases of testosterone concentrations were significantly (p < .01) greater in both loadings in SA than in NA. Both loading protocols in both groups also led to neuromuscular fatigue observable with significant acute decreases in isometric strength by 32-52% (p < .001) and in maximal iEMG (p < .05-01) associated with large increases in blood lactate. These data suggest that, at least in experienced strength athletes, the forced-repetition protocol is a viable alternative to the more traditional maximum-repetition protocol and may even be a superior approach. 相似文献
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Hans Juha Exner Eberhard Schlicker 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(1):46-52
Mouse or rat brain cortex slices were preincubated with 3H-noradrenaline and superfused with physiological salt solution containing desipramine. We studied the effects of prostaglandin E2 (PGE2), prostaglandin D2 (PGD2) and related drugs on the electrically evoked (50 mA, 2 ms, 0.3 Hz) tritium overflow.PGE2 inhibited the electrically evoked tritium overflow from mouse brain cortex slices; the maximum effect of PGE2 (79010) was attenuated by the 2-adrenoceptor agonist talipexole (to 52010) and enhanced by the 2-adrenoceptor antagonist rauwolscine (to 92%). Rauwolscine was added to the superfusion medium in all subsequent experiments. The effect of PGE2 was readily reversible upon withdrawal from the medium and remained constant upon prolonged exposure of the tissue to the prostanoid. Studies with EP receptor agonists, mimicking the inhibitory effect of PGE2, showed the following potencies (pIC50): sulprostone (8.22); misoprostol (8.00); PGE2 (7.74); PGEZ (7.61); iloprost (5.86). The concentration-response curve of PGE2 was marginally shifted to the right by the EP1 receptor antagonist AH 6809 (6-isopropoxy-9-oxoxanthene-2-carboxylic acid; apparent pA2 3.97) and by the TP receptor antagonist vapiprost (4.50). AH 6809, by itself, did not affect the evoked overflow whereas vapiprost increased it. PGD2 inhibited the evoked overflow at high concentrations (pIC50 4.90); this effect was not altered by the DP receptor antagonist BW A868C (3-benzyl-5-(6-carboxyhexyl)-1-(2-cyclohexyl-2hydroxyethylamino)hydantoin), which, by itself, did not affect the evoked overflow. Indometacin slightly increased the evoked overflow and tended to increase the inhibitory effect of PGE2. PGE2 inhibited the electrically evoked tritium overflow also in rat brain cortex slices. The maximum effect (obtained in the presence of rauwolscine) was 61%; the pIC30 value was 7.67.The present study suggests that PGE2 inhibits noradrenaline release from mouse brain cortex via EP3 receptors and that its maximum effect is more marked in the mouse than in the rat. The inhibitory effect of PGD2 (in the mouse brain) does not involve DP receptors and may also be related to EP3 receptors. The EP3 receptors interact with a2-adrenoceptors and may be activated by endogenous prostanoids. 相似文献
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Alcohol reduces prefrontal cortical excitability in humans: a combined TMS and EEG study. 总被引:3,自引:0,他引:3
Seppo K?hk?nen Juha Wilenius Vadim V Nikulin Marko Ollikainen Risto J Ilmoniemi 《Neuropsychopharmacology》2003,28(4):747-754
The effects of alcohol (0.8 g/kg) on the prefrontal cortex were studied in nine healthy subjects using the technique of transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG). A total of 120 magnetic pulses were delivered with a figure-of-eight coil to the left prefrontal cortex at the rate of 0.4-0.7 Hz. The EEG was recorded simultaneously with 60 scalp electrodes (41 electrodes were used for analysis); the TMS-evoked activation was estimated by the area under the global mean field amplitude (GMFA) time curve. TMS caused changes in EEG activity lasting up to 270 ms poststimulus. Alcohol decreased GMFA at 30-270 ms poststimulus (713+/-303 vs 478+/-142 microV ms; p=0.007). Alcohol-induced differences were most pronounced at anterior electrodes. These results suggest that alcohol reduces the excitability in the prefrontal cortex. 相似文献
27.
Juha Juntunen Juhani Huuskonen Krista Laine Riku Niemi Hannu Taipale Tapio Nevalainen David W Pate Tomi J?rvinen 《European journal of pharmaceutical sciences》2003,19(1):37-43
Phosphate esters of arachidonylethanolamide (AEA) and R-methanandamide were synthesized and evaluated as water-soluble prodrugs. Various physicochemical properties (pK(a), partition coefficient, aqueous solubility) were determined for the synthesized phosphate esters. The chemical stability of phosphate esters was determined at pH 7.4. In vitro enzymatic hydrolysis rates were determined in 10% liver homogenate, and in a pure enzyme-containing (alkaline phosphatase) solution at pH 7.4. The intraocular pressure (IOP) lowering properties of R-methanandamide phosphate ester were tested on normotensive rabbits. The phosphate promoiety increased the aqueous solubility of the parent compounds by more than 16500-fold at pH 7.4. Phosphate esters were stable in buffer solutions, but rapidly hydrolyzed to their parent compounds in alkaline phosphatase solution (t(1/2)<15 s) and liver homogenate (t(1/2)=8-9 min). The phosphate ester of R-methanandamide reduced IOP in rabbits. These results indicate that the phosphate esters of AEA and R-methanandamide are useful water-soluble prodrugs. 相似文献
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Keijo Hkkinen Robert U. Newton Simon Walker Arja Hkkinen Sonja Krapi Rebekka Rekola Pivi Koponen William J. Kraemer G. Gregory Haff Anthony J. Blazevich Kazunori Nosaka Juha Ahtiainen 《Journal of Sports Science and Medicine》2022,21(2):200
Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were measured. ECC and CON training led to increases of 17.2 ± 11.3% (p < 0.001) and 13.1 ± 5.7% (p < 0.001) in 1RM followed by decreases of -6.6 ± 3.6% (p < 0.01) and -8.0 ± 4.5% (p < 0.001) during detraining, respectively. Isometric force increased in ECC by 11.4 ± 9.6 % (p < 0.05) from week 5 to 10, while the change in CON by 3.9±6.8% was not significant and a between group difference was noted (p < 0.05). Maximal total integrated EMG of trained muscles increased only in the whole subject group (p < 0.05). CSA of TB (LoH) increased in ECC by 8.7 ± 8.0% (p < 0.001) and in CON by 3.4 ± 1.6% (p < 0.01) and differed between groups (p < 0.05), and CSA of TB (LaH) in ECC by 15.7 ± 8.0% (p < 0.001) and CON by 9.7 ± 6.6% (p < 0.001). PM thickness increased in ECC by 17.7 ± 10.9% (p < 0.001) and CON by 14.0 ± 5.9% (p < 0.001). Total muscle sum value (LoH + LaH + PM) increased in ECC by 12.4 ± 6.9% (p < 0.001) and in CON by 7.1 ± 2.9% (p < 0.001) differing between groups (p < 0.05) and decreased during detraining in ECC by -6.5 ± 4.3% (p < 0.001) and CON by -6.1 ± 2.8% (p < 0.001). The post detraining combined sum value of CSA and thickness was in ECC higher (p < 0.05) than at pre training. No changes were detected in serum hormone concentrations, but baseline free testosterone levels in the ECC and CON group combined correlated with changes in 1RM (r = 0.520, p < 0.016) during training. Large neuromuscular adaptations of the upper body occurred in women during ECC, and CON training in 10 weeks. Isometric force increased only in response to ECC, and total muscle sum value increased more during ECC than CON training. However, no changes occurred in serum hormones, but individual serum-free testosterone baseline concentrations correlated with changes in 1RM during strength training in the entire group. Both groups showed significant decreases in neuromuscular performance and muscle mass during detraining, while post detraining muscle sum value was only in ECC significantly higher than at pre training. Key points
- Maximal eccentric and concentric strength training in women for 10 weeks (only twice a week) led to great gains in dynamic strength of upper body.
- Upper body muscle mass increased more after eccentric than concentric strength training.
- During detraining for 5 weeks both groups showed decreases in strength and muscle mass.
- However, post-detraining combined sum muscle mass value was only in ECC higher than at pre-training.