There was also a significant difference between exposed and sheltered sites for these species (LMM, p < 0.001 and p < 0.01 respectively). In addition, there was an increase over time of G. zaddachi and juvenile gammarids at the exposed sites, measured as the significant difference between the first and last sampling (LMM, p < 0.01 and p < 0.0001 respectively, Appendix). In a similar way

to algae, the biomass GSK2656157 mouse of invertebrates increased significantly over time (LMM, p < 0.01, Appendix, Figure 5). The biomass of G. zaddachi peaked in early May at the wave-exposed sites, while the biomass was low and constant at the sheltered sites ( Table 1b, Figure 4). The biomass was significantly higher at the wave-exposed sites than at the wave-sheltered sites (LMM, p < 0.001, Appendix). In contrast, the biomass of Cardiidae and Hydrobiidae were significantly higher at the wave-sheltered sites (LMM, p < 0.001, p < 0.01, Appendix) ( Figure 4). The increase in biomass of all these species (except Cardiidae) was delayed compared to the algal biomass ( Figure 4, Table 1a,b). Hydrobiidae only increased in abundance at the wave-sheltered sites (p < 0.01, Appendix),

while the biomass of Cardiidae showed no significant changes over time ( Figure 4). Red filamentous algae, in this case 99% C. tenuicorne, were positively correlated with the abundance of M. edulis (LMM, p < 0.001). The isopods Idotea spp. were less abundant, this website but showed Rolziracetam a positive correlation with the non-filamentous algae (LMM, p < 0.05). No specific correlations were found for brown filamentous algae or green filamentous algae with the abundance of any of the invertebrates.

After the sea ice broke up in the middle of March, a community dominated by filamentous macroalgae rapidly established itself in the rocky hydrolittoral zone. As expected, because of increased temperature and light and from the life cycles of the organisms, the biomass increased from the first sample collection in March to the last sample collection in May at three of the sheltered sites and at four of the exposed sites. During the same period, the number of taxa increased only slightly. Three species were mainly responsible for the significant changes in algal biomass over time: Pylaiella littoralis, Ceramium tenuicorne and Fucus vesiculosus ( Figure 5). The peak of P. littoralis and C. tenuicorne occurred in early May, coinciding with the development of increased faunal biomass. In contrast to previous findings in the northern Baltic Sea (e.g. Hällfors et al., 1975 and Rönnberg, 1975), we found a higher macroalgal biomass at the exposed sites than at the sheltered sites on the last two sampling occasions. This difference could be explained by the fact that the present study was performed during spring and because we focused on the hydrolittoral zone (0–0.5 m under MWD). Other comparable investigations (see Hällfors et al.

007) and a trend towards smaller infarct core volumes (18 ml vs 34 ml, p = 0.15) at baseline. TCD monitoring times were not significantly different between groups (major reperfusion, 103 min; non-reperfusion, 124 min; p = 0.34). Consistent with other studies, patients with major reperfusion showed smaller median 24 h infarct

core volumes (28 ml vs 46 ml, p = 0.005), lower 24 h mean NIHSS score (12.1 vs 16.7, p = 0.009), and a higher proportion of patients with favourable 90 day functional outcomes (mRS 0–2, 63% vs 10%, p = 0.002). The TIBI grade profiles for each case is shown in Fig. 1A and B. Major TIBI grade change (improvement by ≥3 grades during the post-thrombolysis monitoring period) was associated with major reperfusion (p = 0.04) GSI-IX order along with higher odds of attenuation of infarct core growth (p = 0.06), improvement in NIHSS score (p = 0.049) and excellent 90 day functional outcome (mRS 0–1; p = 0.03). Major sudden TIBI grade change (improvement of ≥3 grades over ≤15 min) was associated with a trend towards excellent functional outcome (mRS

0–1; p = 0.09). MES were detected in 36% proportion of cases overall, 37% in the patients with major reperfusion and 33% in patients with non-reperfusion (p = 0.55). There was no association between the presence of microemboli and major Veliparib cost TIBI grade change, 24 h infarct core volume or clinical outcomes. This is the first description of the relationship between TCD features of leptomeningeal

collateralisation and recanalization, hyperacute Cyclin-dependent kinase 3 brain perfusion status, and their relationships to tissue fate and clinical outcomes in acute ischemic stroke. Our data demonstrate that the ACA FD is associated with improved LMC and is independently associated with 24 h infarct volume and 90 day clinical outcome in acute anterior circulation stroke patients with identifiable large artery occlusion. ACA FD may therefore define a group of patients who have a greater tolerance to ICA or MCA occlusion and, potentially, a longer-lived ischemic penumbra. Our data also demonstrate that in MCA occlusion patients treated with intravenous thrombolysis, major improvement in TIBI grade is associated with major reperfusion at 24 h along with improved 24 h and 90 day clinical outcome and a trend towards less infarct core growth. Although definitions and indices of ACA flow diversion vary in the literature [17], [20], [21], [22] and [23] the ACA asymmetry index used by Zanette [20], based on comparison between digital cerebral angiography and TCD performed within 6 h of stroke onset, is likely to be the most reliable and easily applicable measure in hyperacute stroke. The same asymmetry index was used to define TCD FD in the retrospective analysis of the CLOTBUST trial. In this study, FD was observed in 83% of patients with MCAO treated with tissue plasminogen activator therapy.

Differences were also shown between the LD50 of newborns and adults snake venoms (Furtado et al., 2003). The present study demonstrated important differences in venom constitution of Cdt males, females and newborns with an emphasis on the comparison of venoms originating from the wild versus those obtained in captivity. These observations

reinforce the necessity of including in all such scientific studies the exact origin of the venom samples, since there are large variations NSC 683864 in the proteins, biology and biochemistry within the same specie. Finally, care must be taken in the preparation of antivenoms in selecting snakes that will nourish venom to prepare the pool that will be employed in the immunization of serum-producing animals. The present results have demonstrated individual variation in Cdt venoms, noteworthy for the production of efficient antivenom. Thus, the “pool” to be used must be made up by a well balanced mixture of several extractions performed in different seasons of the year, obtained from specimens originating from different regions of the country, of both sexes and different ages, all appropriately managed (diet include), since the intra-specimens variation seems not to be an exception, but the rule. These results will allow evaluation using new methodology approaches

( Georgieva et al., 2010) as mass spectrometry or 2D-SDS to improve the Cytidine deaminase venom characterization click here especially low abundance molecules. The authors are grateful for funding through FAPESP

Proc. No. 2009/53846-9 (BB and RSFJr) and FAPESP Proc. No. 2009/06280-0 (RSFJr) and CNPq Proc. No. 473622/2009-2, FAPESP Proc. No. 2009/09774-3 (RSFJr and CFZC), and extend special thanks to The Center for the Study of Venoms and Venomous Animals, CEVAP, and Tropical Diseases Department at São Paulo State University, UNESP, Brazil. DCP is a CNPq fellow (302405/2008-9) and is also supported by funds of the INCTTOX PROGRAM – CNPq/FAPESP. RSFJr is also a CNPq fellow researcher (310207/2011-8). “
“The phylum Arthropoda, including spiders, scorpions, insects and others, is the largest phylum in the animal kingdom (Toewe, 1990). Many spiders and scorpions produce venoms that can cause skin lesions, systemic disorders, neurotoxicity, and death (Goddard, 1996; Diaz, 2004). A huge variety of components, including several toxins with different targets, can be found in the venom of arthropods, what makes them a rich source of bioactive peptides. Many symptoms are observed following a bite or sting of these animals. Because priapism is one of these symptoms, those venoms began to be investigated in order to indentify active peptides in the erectile mechanism.

, 1966 and Ferguson and Good, 1980). With the restriction of weak complexing capacity monophosphate buffers with potassium or sodium as counter ions are broadly applicable. As already mentioned above, the capacity range of buffers is narrow, comprising two pH units at best. If a broader range is required, e.g. for analysing the pH dependence of an enzyme, several buffer systems may be combined. This is, however, an unsatisfactory procedure, due to the varying activities of the enzymes

in different buffers. In such cases universal buffers, like the Teorell–Stenhagen and the Britton–Robinson buffer, consisting of more than two components and covering a broad pH range, should be used (Bisswanger, 2011 and Teorell and Stenhagen, 1939). Finally it must be considered that dissociation Small molecule library cell assay of compounds and, consequently, also of buffers, depends strongly RO4929097 datasheet on

the temperature. Therefore the pH changes with the temperature and for exact pH specification the prevailing temperature must be indicated. Usually 20 °C is used as standard temperature for buffers and the pKa values refer to this temperature. According to the cellular milieu water is the standard solvent for enzyme assays. Only for special cases, like enzymes connected with the membrane, e.g. lipases, apolar organic solvents are used, while such solvents will denature most enzymes. However, for some enzyme assays organic solvents cannot be completely avoided, e.g. when an essential component, like a substrate, is sparingly soluble in water. It must be dissolved in higher concentration in an organic, water-miscible solvent, like ethanol, DMSO or acetone. An aliquot Abiraterone supplier of this solution is added to the assay mixture, where it should remain dissolved in its final concentration. To keep the concentration of the organic solvent in the assay mixture as small as possible the volume of the aliquot should be rather small.

In such cases the problem arises that smaller volumes require a higher concentration of the component in the organic solvent and it may immediately precipitate upon addition to the aqueous assay mixture. To prevent precipitation either the final concentration of the weakly soluble compound in the assay mixture must be kept rather low, or the fraction of the organic solvent in water must be higher to mediate solubility. So the ratio of the organic solvent in the assay mixture is directly connected with the concentration of the weakly soluble compound and sometimes lower concentrations than effectively required must be accepted. Further it has to be considered that solubility depends strongly on temperature, e.g. the compound can be just soluble at the assay temperature, but may precipitate if the assay mixture is kept in the cold before testing.

The monthly mean values of the aerosol

optical thickness in summer 2002 were considerable much than in the other years considered. A particularly high monthly PLX4032 mean AOT(500) for 2002 was recorded in August, when it reached 0.323 ± 0.237. For comparison, the monthly mean aerosol optical thicknesses in the Augusts of the other years varied from 0.065 ± 0.050 in 1999 to 0.139 ± 0.079 in 2003 (Figure 4a). The monthly mean values of < α(440, 870) > from June to September of 2002 also reached exceptionally high values ( Figure 4b). The monthly mean values of the aerosol optical thickness AOT(500) in July and August of 1999 were the lowest of all. The aerosol optical thickness above Gotland is influenced not only by periodic and incidental phenomena near the Baltic Sea shore, but also by distant continental phenomena. The origin of air masses advecting over Gotland has an impact on the aerosol optical thickness as well as the Ångström exponent. Based on a synoptic map analysis of AOT(500) measurements over five years, AOT(500) values < 0.100 were linked to the advection of maritime Arctic and maritime Polar air masses over the Baltic area. The advection of continental Polar air above the Baltic (six-day BYL719 nmr backward trajectories leading from over central Europe) can increase the aerosol optical thickness up to 0.682 (± 0.025),

as observed on 1 April 2002. In summer 2002, fires intensified by persistent drought contributed to the high values of the aerosol optical thickness. Monthly composite satellite

images available from FIRMS (The Fire Information for Resource Management System) show the particularly numerous forest and field fires in northern Europe, Russia, Ukraine and Belarus in 2001 and 2002. Moreover, in summer 2002 the modal wind direction was different from that in the other summers considered here. For example, north-easterly winds (40°) were predominant in August 2002, whereas winds from the north-west (300° and 310°) were the most frequent in 1999, 2001 and 2003. The specific synoptic situation in 2002 favoured the transport of aerosol towards Gotland derived from the biomass burning. For example, the biomass burning aerosols transported over the Baltic Sea along with advecting air on 31 July or 12 August 2002 resulted in < AOT(500) >31072002 = 0.661 ± 0.084 and < AOT(500) >12082002 = 0.62 4 ± 0.162. The enlarged emission of aerosol and an Mannose-binding protein-associated serine protease increase in AOT(500) in spring was presumably related to agricultural waste straw burning (Niemi 2003). It is worth noting that during the time period under scrutiny, cases of air advection from Africa at 3000 m above the Baltic region were observed in spring and summer. However, at lower altitudes the air then usually came from the burning regions of Russia, Ukraine and Belarus. In such cases the daily mean aerosol optical thicknesses for λ = 500 nm were lower (i.e. < AOT(500) >12042002 = 0.261 ± 0.055, < AOT(500) >12052002 = 0.249 ± 0.038, < AOT(500) >13082002 = 0.416 ± 0.

This suggests that general motor processing and visual-spatial memory is reflected in the cognitive processor, whereas effector specific preparation is reflected in the motor processor. Concluding, differences between familiar and unfamiliar sequences were already present during the preparation of sequences. More specifically, the load on general motor preparation and visual-working memory is increased during the preparation of unfamiliar sequences, as compared AZD2281 solubility dmso with familiar sequences. The load on general motor preparation is suggested to decrease with

practice as there is a shift from preparation of individual movements to segment of movements. In line with this, the load on visual-working memory is suggested to decreases with practice as segments of responses can be kept in visual-working

memory instead of individual responses. This suggests that sequence learning indeed develops from an attentive to a more automatic phase. “
“The question whether one’s current emotional state influences one’s cognitive abilities has been investigated in various domains. Positive mood has been shown to modulate cognitive functions, although the exact influence has been shown to vary between different functions: positive affect has been found to either impair or improve performance depending on the specific task. On the one hand, induced positive Wnt cancer affect improves verbal fluency (Philips, Bull, Adams, & Fraser, 2002) and reduces interference between competing response alternatives in a Stroop-task (Kuhl & Kazén, 1999). On the other hand, positive affect has been shown to increase response interference due to increased distractibility (Rowe, Hirsh, & Andersen, 2007) and to impair performance on certain executive function tests (Oaksford, Morris, Grainger, & Williams, 1996). Carnitine palmitoyltransferase II A series of studies by Dreisbach and colleagues revealed that positive affect results

in flexibility benefits, but also in maintenance costs (distractibility) (Dreisbach, 2006, Dreisbach and Goschke, 2004 and Dreisbach et al., 2005). The exact effect of positive affect on cognitive control is therefore still unclear. To further delineate the modulatory effects of induced positive affect on cognitive control, we used a task that allowed us to study a specific aspect of cognitive control: the inhibition of reflexive eye movements (‘oculomotor inhibition’). During the so-called antisaccade task, participants either make a saccadic eye movement towards the appearing stimulus after stimulus onset (i.e. prosaccade trials) or a saccade in the opposite direction as quickly as possible (i.e. antisaccade trials). Correct performance in the antisaccade task requires the inhibition of the automatic response to the stimulus onset.

, 2007). BoNT is produced as a dichain polypeptide that is then cleaved into a ~ 100 kDa heavy

chain (HC) and a ~ 50 kDa light chain (LC) (Montal, 2010). While the HC facilitates entry of the toxin into neurons by endocytosis, the LC is a metallopeptidase that cleaves soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs), inhibiting acetylcholine release and resulting in flaccid muscle paralysis ( Montal, 2010 and Schiavo et al., 2000). In humans, a lethal dose intravenously or intramuscularly is estimated at 1–2 ng/kg body weight; orally at 1 μg/kg and 10–12 ng/kg by inhalation ( Arnon et al., 2001). Given their potency, BoNTs have been employed as INCB018424 therapeutics, as tools in basic science research, and as weapons of biological warfare (Arnon et al., 2001 and Shukla and Sharma, 2005). The gold standard of

detection of BoNTs is the mouse bioassay, which can detect as little as 10 pg/mL of toxin (Sharma and Whiting, 2005). However, the assay requires several days to complete, large numbers of animals and can only be performed at a select number of laboratories in the United States. To determine the serotype, a second, independent neutralization assay is required. Ribociclib In the event of a suspected BoNT contamination event, the mouse bioassay, while extremely sensitive, does not meet the needs of emergency responders. Therefore a rapid, sensitive, and selective BoNT diagnostic test that can be field deployed could be used to address suspect BoNT contamination. A number of in vitro assays to detect BoNTs, including ELISA kits, PCR-based methods and assays based on the enzymatic activity of the toxin’s light chain have been developed ( Chao et al., 2004, Wictome et al., 1999 and Shone et al., 1985). While some of these methods have comparable sensitivity to the mouse bioassay, they still require trained personnel and specialized equipment. In contrast, lateral flow devices (LFDs) are simple, low cost

alternatives Buspirone HCl that can be easily deployed in the field and do not require specialized training to operate or to interpret the results. LFDs can be read without optical detection systems, are compact, and on average have a long shelf life ( Posthuma-Trumpie et al., 2009, Warsinke, 2009 and Ngom et al., 2010). While these devices typically have less sensitivity than ELISA formats, they do offer a method for rapid, simple assessment of potential BoNT contamination to a multitude of personnel. Our laboratory has developed several high affinity monoclonal antibodies (mAbs) that selectively recognize the BoNT/A and /B serotypes. MAb F1-2, which recognizes the N-terminus of the heavy chain of BoNT/A, has been extensively characterized and effectively employed as a capture antibody in a sandwich ELISA (Scotcher et al., 2009 and Stanker et al., 2008). We have also previously described MCS-6-27, a BoNT/B-specific mAb that binds the carboxyl portion of the HC and can be used as a capture antibody in a sandwich ELISA (Scotcher et al.

The different dependencies observed for BASP1 ( Fig. 6) convincingly illustrate the potential of the methodology

to probe differential side-chain dynamics in IDPs. In future applications it is planned to extend the methodology to higher frequency dimensions exploiting non-uniform sampling techniques. Details of the sequence and results will be reported elsewhere (manuscript in preparation). IDPs are involved in fundamental biological (physiological) processes and are, therefore, of great interest to medical and pharmaceutical PF-02341066 order research [40]. Their inherent structural flexibility allows them to accommodate different binding partners exploiting different binding modes (e.g. folding-upon binding or formation of fuzzy complexes). Despite limitations due to their unfolded nature several successful studies have been reported demonstrating that IDPs are indeed amenable to drug development programs [41]. However, the dynamic nature of IDPs impairs the application of conventional structure-based drug design strategies. The lack of 3D structures as bottleneck in the pharmaceutical industry is widely recognized and was recently addressed by a combination of information-rich

selleck chemicals NMR and new protein sequence analysis tools (e.g. meta-structure) [34] and [42]. It was already demonstrated that the meta-structure analysis provides valid starting points for ligand development by revealing information about the construction of suitable fragment libraries and ligand binding modes [42]. Given the fact that only primary sequence information is needed, valuable applications also to ligand

identification for IDPs can be anticipated. A prototypical application to IDPs is given with the example of Osteopontin (OPN), an extracellular matrix protein associated with metastasis of several kinds of cancer. The meta-structure analysis revealed a similarity to the (folded) protein Staurosporine antithrombin. The naturally occurring, highly sulfated glycosaminoglycan heparin is an established ligand for antithrombin. Heparin binding to OPN was verified using NMR spectroscopy [37]. It was shown that heparin binding to OPN causes significant and specific chemical shift changes. This example illustrates how the combined usage of meta-structure and NMR data can be used to create valid starting points for drug development programs involving IDPs. In subsequent steps NMR spectroscopy can be used to provide additional information about binding modes and orientations of bound ligands [42]. Naturally, a comprehensive analysis has to address both structural and dynamical changes. In a recent NMR analysis we have employed both PRE and 15N NMR relaxation data to analyze the interaction between the IDP Osteopontin (OPN) and heparin (manuscript in preparation). Fig. 7 shows differential PREs and 15N relaxation parameters (15N-T2 and 1HN–15N NOE).

, 2005). Hydrogen sulphide is acutely toxic with fatalities associated with concentrations in excess of 500 ppm. It has a very low odour threshold (0.008 ppm) but odour perception is lost at concentrations of 150–250 ppm (WHO, 2000), adding to the danger of high level exposures as they may not be recognised, by smell, by the individual. In Europe, there is a workplace exposure limit (8 h TWA) of 5 ppm (HSE, 2011 and SCOEL, 2007) with a

short-term (15-min) exposure limit of 10 ppm. Hydrogen sulphide has previously been reported as a causal agent of unconsciousness and death in a number of occupational exposure incidents (Kage et al., 2002 and Kage et al., 2004). In the UK it has been reported (Costigan, 2003) that around 125,000 workers in the UK are potentially exposed to hydrogen sulphide in work related to the treatment of sewage, effluent waste and farm slurry. check details In the offshore oil and gas industries about 3000 workers are potentially exposed. The UK Health and ATM/ATR activation Safety Executive has investigated several incidents of workplace accidents involving hydrogen sulphide exposure from slurry pits, animal rendering plants and biodigester facilities

in recent years. The increased prevalence of biodigesters and slurry storage may indicate an increased likelihood of further incidents in the future. Here we report three case studies using biological monitoring to determine hydrogen sulphide exposure. Blood or urine thiosulphate determination was carried out according to the method of Kage et al. (1991). Briefly, samples (200 μl) were buffered with ascorbic acid (200 mM, 50 μl) and 5% sodium chloride (50 μl) then derivatised using pentafluorobenzyl bromide (20 mM in acetone, 500 μl) and extracted into iodine ethyl acetate solution (25 mM, 2 ml) to form bis(pentafluorobenzyl)

disulphide. Tribromobenzene was used as an internal standard. Analysis was by gas chromatography–mass spectrometry (positive electron ionisation) using selected ion monitoring (m/z 426 for the thiosulphate derivative). Aliquots (1 μl) were injected (220 °C, splitless) onto a BP-5 equivalent column (30 m × 0.32 mm i.d., 1 μm film) with a helium flow of 1 ml/min. The oven temperature many was held at 100 °C for 2 min then ramped at 10 °C/min up to 220 °C, where it was held for 5 min. Calibration standards were prepared in blood or urine, as appropriate, and extracted as per the samples. The calibration curves were linear from 0 to 600 μmol/l (least squares regression > 0.99) and quality control samples were within the expected range showing a coefficient of variation of 12%. The detection limit was 1 μmol/l. Urine samples were also analysed for creatinine content using the alkaline picrate reaction ( Cocker et al.

53, p < 0.01: Fig. 6) and Mn × sex × age interactions (F(4,168) = 2.46, p < 0.05). Further analyses showed these to be predominantly

expressed in males irrespective of rearing condition and occurred in the Mn50 group at P11 and in the Mn100 group at P29 (both were increases; Fig. 6E). Hippocampal 5-HT showed a Mn main effect (F(2,171) = 11.33, p < 0.0001: Fig. 7) and a Mn x age interaction (F(4,171) = 2.42, p < 0.05). Further analysis showed that the main effect was attributable to increased 5-HT in the Mn groups, whereas the Mn x age interaction showed the effect to be predominately on P29 (Fig. 7E). For 5-HIAA, the only effect was a Mn x age interaction which when further analyzed was attributable to reduced 5-HIAA in the Mn groups at P19 selleck irrespective of sex or rearing condition (Fig. 7F). Monoamines in the hypothalamus were altered (Fig. 8 and Fig. 9). For DA there was a 4-way interaction of Mn × sex × rearing condition × age (F(4,206) = 2.4, p < 0.05). When further analyzed, this interaction was attributable to DA increases in the barren-housed female Mn100 group at P19 and both Mn groups at P29 compared with VEH animals at those ages (Fig. 8D). There were no significant treatment effects found on DOPAC. For hypothalamic NE, there was also a 4-way interaction of Mn × sex × rearing condition × age (F(4,216) = 3.03, p < 0.05). In this case, further analysis selleck inhibitor showed increases in NE in standard-housed males at P29 in the Mn100 group

and a trend in the Mn50 group (Fig. 9A) and a similar trend in the barren Mn100 females at this age (Fig. 9D). For HVA, there was a significant Mn × sex interaction (F(2,123) = 3.33, p < 0.05; Fig. 10) which when further analyzed was attributable to increased HVA in the Mn100 males compared with VEH males (Fig. 10E). There were no significant Mn or rearing effects on hypothalamic 5-HT (Fig. 11A-E). A main effect of Mn was found for 5-HIAA (F(2,213) = 3.75, p < 0.05) in which the Mn groups had lower 5-HIAA levels than

VEH animals irrespective of sex or housing condition (Fig. 11F). As noted in Methods, litters 1 or 2 pups short of the 12 needed per litter had 1 or 2 pups in-fostered many from litters born within 24 h of the litter that had too few born. Out of the 116 litters used for corticosterone and monoamine determinations, a total of 36 pups out of 1392 pups were in-fostered or 2.6%. Within the Standard housing condition a total of 22 pups were in-fostered out of 696 pups or 3.2%. Within the Barren housing condition a total of 14 pups were in-fostered out of 696 pups or 2.0%, making it unlikely that this proportionately small amount of in-fostering would significantly impact either the corticosterone or monoamine responses of the treatment groups. This experiment tested whether two dose levels of Mn during postnatal development under standard or barren cage rearing conditions altered corticosterone and brain monoamines at different developmental ages.