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Lung cancer is the most common cause of cancer-related mortality worldwide, characterized by late clinical presentation (49-53% of patients are diagnosed at stage IV) and consequently poor outcomes. One challenge in identifying biomarkers of early disease is the collection of samples from patients prior to symptomatic presentation. We used blood collected during surgical resection of lung tumors in an iTRAQ isobaric tagging experiment to identify proteins effluxing from tumors into pulmonary veins. Forty proteins were identified as having an increased abundance in the vein draining from the tumor compared to "healthy" pulmonary veins. These protein markers were then assessed in a second cohort that utilized the mass spectrometry (MS) technique: Sequential window acquisition of all theoretical fragment ion spectra (SWATH) MS. SWATH-MS was used to measure proteins in serum samples taken from 25 patients

Understanding the normal temporal variation of serum molecules is a critical factor for identifying useful candidate biomarkers for the diagnosis and prognosis of chronic disease. Using small RNA sequencing in a longitudinal study of 66 women with no history of cancer, we determined the distribution and dynamics (via intraclass correlation coefficients, ICCs) of the miRNA profile over 3 time points sampled across 2–5 years in the course of the screening trial, UKCTOCS. We were able to define a subset of longitudinally stable miRNAs (ICC >0.75) that were individually discriminating of women who had no cancer over the study period. These miRNAs were dominated by those originating from the C14MC cluster that is subject to maternal imprinting. This assessment was not significantly affected by common confounders such as age, BMI or time to centrifugation nor alternative methods to data normalisation. Our analysis provides important benchmark data supporting the development of miRNA biomarkers for the impact of life-course exposure as well as diagnosis and prognostication of chronic disease.

Background: Lung cancer is the most common cause of cancer related mortality worldwide, characterised by late clinical presentation (49-53% of patients are diagnosed at stage IV) and consequently poor outcomes. One challenge in identifying biomarkers of early disease is the collection of samples from patients prior to symptomatic presentation. An additional complication in determining differential biomarkers arises from protein expression change from non-specific systemic responses and co-morbidities such as Chronic Obstructive Pulmonary Disease (COPD). Methods: We employed isobaric tagging, relative quantification mass spectrometry to analyse protein markers that differed in blood entering and egressing from the tumour bearing lobe of the diseased lung immediately prior to lung resection surgery. These potential biomarkers were assessed as lung cancer early detection biomarkers using the orthogonal mass spectrometry (MS) technique Sequential window acquisition of all theoretical fragment ion spectra (SWATH) MS which we showed had equivalent quantification value to a selected reaction monitoring (SRM) approach. Findings: In a second cohort, SWATH-MS was used to measure 974 proteins in serum samples taken

Coastal areas are already at high risk from a range of geohazards. The cumulative effect of human intervention on soft coastlines has frequently left them far from equilibrium under today’s conditions, especially in densely populated areas. Future changes in marine forcing due to climate change reinforce the need to understand and predict processes of change in shoreline position and configuration at management (decadal) scales. The UK-based iCOASST project is developing new and improved methods to predict decadal geomorphic evolution, linked to coastal erosion and flood risk management. This is based on a framework that links several components to develop a system-level understanding of this change. The framework includes: (1) new methods for system-level analysis and mapping of coast, estuary and inner shelf landform behaviour; (2) well validated ‘bottom-up’ hydrodynamic and sediment transport shelf models which can be applied at shelf scales to investigate inner shelf-coastal interactions; and (3) model compositions formed of existing or new ‘reduced complexity models’ of selected coastal landforms and processes that are suitable for multiple decadal length simulations. This will ultimately allow multiple simulations of coastal evolution which can explore uncertainties in future decadal-scale coastal response, including the effects of climate change and management choices. This paper outlines the current state of progress in the iCOASST Project.

Interpretation of data from gene targeting studies can be confounded by the inherent traits of the background inbred strains used in the generation of transgenic and null mutant mice. We have therefore compared the behaviour and response to CNS injury of four inbred strains commonly used in molecular genetic studies to produce models of neurological disease. Adult, male 129/Ola, BALB/c, C57BL/6 and FVB/N mice (2-4 months) were initially subjected to behavioural tests that comprised a neurological examination, determination of motor function and cognitive testing in the Morris water maze. Also the response to CNS injury following an acute kainic acid (KA) challenge (30 mg kg-1, i.p.) was determined. The 129/Ola and BALB/c strains showed significant motor deficits when compared with the C57BL/6 and FVB/N strains. In contrast, only the FVB/N strain showed evidence of apparent cognitive impairments in the water maze as evidenced by increased pathlengths to locate the escape platforms and impaired performance in a probe trial. In addition, the FVB/N strain showed the most severe seizure response and mortality rate (62%) following administration of KA (30 mg kg-1, i.p.). These behavioural changes were also associated with a greater degree of cell body and synaptophysin loss in the pyramidal CA3 hippocampal cell layer and astrogliosis 72-h post-dose. These data suggest that the FVB/N strain may not be the most suitable background strain for the development of new transgenic mice for the study of genes implicated in the learning and memory process.

The influence of entorhinal cortex lesions on behaviour and concommitant changes in synaptophysin immunoreactivity (IR) in the denervated dentate gyrus was assessed. Male, C57/B6 mice received either bilateral (BI), unilateral (UNI), or no lesion (SHAM) to the entorhinal cortex. At various stages post-lesion the animals were evaluated in tests to examine neurological and cognitive (spatial and cued learning, Morris water maze) function. UNI lesioned animals from 6-36 days post-lesion showed no neurological nor marked cued learning deficit, yet a profound spatial learning deficit. However by 70 days post-lesion, spatial learning ability was clearly evident. In contrast, BI lesioned animals showed severe spatial learning deficits throughout the test period (6-70 days), cued learning was also impaired. In parallel groups of UNI lesioned mice, 6-36 days post-lesion there was a marked reduction (-40%) in synaptophysin IR in the dentate gyrus molecular layer. However by 70 days post-lesion a clear increase in this measure was noted. Changes in the expression of the growth associated protein, GAP43, were also noted over this period. Taken together, the present results suggest some recovery of spatial learning following unilateral entorhinal cortex lesions in mice. This behavioural recovery of a hippocampally dependant task may be associated with a recovery of function related to the synaptic remodelling and elevation of synapse number in the denervated hippocampus, as evidenced by changes in synaptophysin and GAP43 IR.

There are three isoforms of the 33-kDa protein apolipoprotein E (apoE), termed apoE2, apoE3, and apoE4, each encoded by distinct genes APOE2, APOE3, and APOE4, respectively. In 1993, the APOE genotype was identified as a risk factor for Alzheimer's disease (AD) and was subsequently acknowledged to account for approximately 60% of all cases. The influence of the APOE genotype in AD is clearly isoform dependent, APOE4 imparting susceptibility and APOE2 protection. Thus, patients homozygous for the E4 allele show a very strong likelihood of developing the disease by age 75, whereas patients carrying at least one E2 allele are unlikely to develop symptoms of AD by this age. A major issue in AD research is therefore to understand the functional differences between the ApoE isoforms, with the ultimate aim of designing the next generation of drugs to treat this disease. The purpose of the present article is to summarise some of this work. This review encompasses the rapidly developing molecular, cellular, and behavioural research into ApoE, and attempts to highlight those findings we consider to be of particular significance.

Discomfort results when sweat accumulates on the skin. The sorption of water vapor by hygroscopic clothing near the skin and its release when the clothing moves away from the body can enhance sweat removal. Such a process depends on the relative humidity being higher near the skin than in the ambient atmosphere, and may accompany heavy sweating. Experiments and theoretical models have indicated that a small effect of this kind may occur in wear.

We have examined the specific binding of the tritiated derivative of the potent histamine H 3 receptor antagonist, [3,4- 3 H 2 ]-cyclohexyl-{[4-(3 H -imidazol-4-yl)-piperidin-1-yl]iminomethyl}-amine ([ 3 H]GR168320), to homogenates of rat cerebral cortex. Specific binding of [ 3 H]GR168320 at 37°C associated and dissociated rapidly. Binding was saturable ( B max 412 ± 89 fmol/mg protein) and of high affinity ( K d 0.12 ± 0.11 nM). Saturation studies suggested the involvement of a single site. Histamine H 3 receptor agonists and antagonists inhibited [ 3 H]GR168320 binding with high affinity. Agonist and antagonist affinities correlated when compared with affinities obtained using the tritiated histamine H 3 agonist radioligand N α -methylhistamine.

Replacement of the isothiourea moiety of known histamine H 3 antagonists by certain 5-membered heteroaromatic systems can give compounds with an improved activity profile. One of these, 3-[(4-chlorophenyl)methyl]-5-[2-(1H-imidazol-4-yl)ethyl] 1,2,4-oxadiazole (GR175737) is a potent, selective, orally active and centally penetrating H 3 antagonist.

Hexagonal crystals of H 9 Ln 7 Ce 6 (SO 4 ) 27 .72H 2 O are known for Ln = La-Tb. The Tb compound is isomorphous with the Nd compound described previously. Tb-O (2.55 A average) is unusually long compared with a typical literature value of 2.43 A and, in spite of the lanthanide contraction, is longer than the corresponding Nd-D distance although the Ce-O distances are identical. Since the quality of the crystals and hence the data is not as good for the Tb compound, and since this phase has not been reported for Ln = Dy-Lu, it may be that the size of the Ln III site is fixed by the Ce IV -SO 4 2- network.

1. The contractile responses to angiotensin II, angiotensin III and two synthetic analogues, [Lys2]angiotensin II and [Sar1]angiotensin II, in the guinea-pig isolated longitudinal muscle preparation of small intestine have been characterized in vitro. 2. Tachyphylaxis to the angiotensin analogues was reduced by use of a Krebs-Henseleit solution containing a raised (sub-contractile) concentration of potassium (11.2 mM). Under these conditions. reproducible cumulative concentration-response curves to all agonists were established. The pD2 estimates for angiotensin II, [Lys2]angiotensin II, angiotensin III and [Sar1]angiotensin II were 9.15 +/- 0.14, 7.42 +/- 0.06, 7.69 +/- 0.18 and 9.50 +/- 0.15 respectively and the maximum responses achieved were not significantly different. 3. The contractile responses to angiotensin II, angiotensin III and [Sar1]angiotensin II were reduced by greater than 80% by tetrodotoxin (TTX; 0.1 microM). However, the responses to [Lys2]angiotensin II were reduced by only 63 +/- 5%. Atropine (0.1 microM) also reduced the responses to angiotensin II, angiotensin III and [Lys2]angiotensin II, although its effect was less than that produced by TTX. Furthermore, while responses to these agonists were not significantly modified by the NK1 receptor antagonist (+/-)-CP-96,345 (30 nM) alone, the combined pre-incubation with both atropine and (+/-)-CP-96,345 reduced maximum agonist responses to a level not significantly different from those produced by TTX. 4. Indirect and direct contractile responses to angiotensin II and [Lys2]angiotensin II (in the presence of TTX) respectively were characterized by use of the selective AT1 receptor antagonist, losartan and the AT2 receptor antagonist, PD123177. Losartan produced parallel rightward displacement of the concentration-response curve to angiotensin II and [Lys2]angiotensin II, with an estimated pKB of 8.56(8.42-8.68) and 9.18 (8.63-9.50) respectively. The AT2 receptor antagonist, PD123177 (3 microM) failed to modify the contractile responses to either angiotensin II or [Lys2]angiotensin II.5. We conclude that two populations of angiotensin II receptors exist in the guinea-pig longitudinal muscle of small intestine, one located neuronally mediating the release of both acetylcholine and substance P and the other located on the smooth muscle mediating direct contractile responses. The neuronal component provides the major contribution to the agonist responses. Both receptor populations are of the AT1 receptor subtype.

Replacement of the isothiourea moiety of known histamine H 3 antagonists by certain 5-membered heteroaromatic systems can give compounds with an improved activity profile. One of these, 3-[(4-chlorophenyl)methyl]-5-[2-(1H-imidazol-4-yl)ethyl] 1,2,4-oxadiazole (GR175737) is a potent, selective, orally active and centally penetrating H 3 antagonist.

The in vivo central effects of a range of full and partial muscarinic receptor agonists have been investigated on hippocampal theta rhythm and blood pressure. In the isoflurane-anaesthetised rat, pretreated with N-methylscopolamine, i.v. administration of arecoline, oxotremorine, arecaidine propargyl ester, aceclidine and pilocarpine produced dose-dependent increases in the frequency of hippocampal theta rhythm and blood pressure, with an order of potency of arecoline = oxotremorine = arecaidine propargyl ester greater than aceclidine greater than or equal to pilocarpine. To increase theta wave frequency, pilocarpine showed a low maximum response and possessed antagonist activity against arecoline, indicating that pilocarpine was acting as a partial agonist. AF102B failed to alter blood pressure or theta rhythm. Intraventricular injections of scopolamine and the M1 receptor-selective antagonist, pirenzepine, produced dose-dependent antagonism of the enhanced theta wave frequency and hypertensive response produced by arecoline. The differences in antagonist potency for the two responses was less than 6-fold, which indicated that both the increase in hippocampal theta wave activity and increase in blood pressure may have been mediated through muscarinic receptors of the M1 subtype. Further studies using a wider range of antagonists will be required to confirm this conclusion.

Considerable evidence exists that the brains of individuals with Alzheimer's disease are subject to elevated levels of oxidative stress, particularly in regions exhibiting pathological damage. A major contributor to this oxidative stress appears to be the inflammatory process. Activation of rodent microglial cells by LPS or beta-amyloid peptide results in a marked up-regulation of inducible nitric oxide synthase (iNOS) and corresponding nitric oxide (NO) production. Elevated levels of iNOS are also observed in the brains of Alzheimer patients. The reaction of NO with superoxide leads to the generation of the highly reactive and damaging peroxynitrite free radical species. Peroxynitrite appears to play a key role in the generation of an oxidative stress in the Alzheimer brain as evidenced by widespread nitrotyrosine immunoreactivity. We have employed SIN-1 as a peroxynitrite generating system in cell cultures in order to characterize the effects of this free radical on neurons. SIN-1 treatment of primary rat hippocampal neurons in culture results in neurotoxicity by a necrosis mechanism according to electron microscopic criteria. One approach to limiting peroxynitrite mediated damage is to limit superoxide production. An approach we have evaluated is treatment with salen manganese compounds, a class of catalytic antioxidant compounds which behave as superoxide dismutase (SOD)/catalase mimetics to detoxify superoxide. A number of such salen manganese compounds, including EUK-8 and EUK-134, can markedly protect primary rat cortical neurons from hydrogen peroxide mediated oxidative stress. Such salen manganese compounds can similarly afford marked neuroprotection to an oxidative stress imposed by SIN-1, potentially attributable at least in part to their inherent SOD activity. The salen manganese SOD/catalase mimetics represent a promising class of catalytic antioxidant for attenuating oxidative stress.

We describe the thorough characterisation of a new transgenic mouse line overexpressing the 695-amino acid isoform of human amyloid precursor protein harbouring the Swedish double familial Alzheimer's disease mutation. This line, referred to as TAS10, exhibits neuropathological features and cognitive deficits that are closely correlated to the accumulation of Abeta in their brain and that are reminiscent of those observed in AD. Data on the TAS10 line are presented at five time points: 2, 6, 12, 18 and 24 months in a longitudinal study. The TAS10 line is characterised by the following changes: i) significant age-related increases in the levels of total and individual species (1-40, 1-42) of beta-amyloid in the brains of transgenics compared with non-transgenic littermates; ii) transgenic mice showed pronounced spatial learning deficits in the Morris water maze at 6 months and working memory deficits by 12 months; iii) amyloid plaque and associated pathologies were observed by the 12-month time point and the burden increased substantially, particularly in the cortex, by 18 months; iv) electron microscopy of the hippocampus of transgenic mice showed evidence of abnormal ultrastructural features such as dystrophic neurites and lipid deposits that developed from 6 months and increased in number and severity with age. Morphometric studies demonstrate that the synapse to neuron ratio is higher in transgenics than in control mice at 12 months, but this ratio decreases as they age and synapse size increases. Thus, this mouse model exhibits a close correlation of amyloid burden with behavioural deficits and ultrastructural abnormalities and so represents an ideal system to study the mechanisms underlying the impact of amyloid pathology on CNS function.

Tracking position and orientation accurately and precisely is important in effective virtual reality systems. Large volume trackers are necessary to build effective augmented reality systems. A new approach to large-volume six-degree-of-freedom tracking is presented. The approach uses ultrasonic measurement technology and cellular deployment to achieve a relatively low-cost large-volume tracker. >

We describe a 2-/spl mu/m diode-pumped, room temperature Ho:Tm:YLF laser and end-pumped amplifier system. The Ho:Tm:YLF oscillator utilized a multiple folded resonator with eight mirrors. A Q-switched output energy of 109 mJ pulse was obtained at 6 Hz. This new design makes the laser a smaller size, which can be used in space application. The effects of the laser operating temperature, thermal focusing and resonator structure rigidity on the performance of the laser were also investigated. In order to increase the laser system energy and efficiency, an end-pumped Ho:Tm:YLF disk amplifier was designed. Preliminary results showed that the efficiency of this laser amplifier could be better than 3% during Q-switch operation, a factor of three increase over side-pumped amplifier configuration. The laser system performance and its potential use for remote sensing of wind are presented.

Using apolipoprotein E knockout mice derived from the Maeda source [Piedrahita J. A. et al. (1992) Proc. natn. Acad. Sci. U.S.A. 89, 4471–4475], we have studied the influence of apolipoprotein E gene deletion on normal CNS function by neurological tests and water maze learning, hippocampal ultrastructure assessed by quantitative immunocytochemistry and electron microscopy, CNS plasticity, i.e. hippocampal long-term potentiation and amygdaloid kindling, and CNS repair, i.e. synaptic recovery in the hippocampus following deafferentation. In each study there was little difference between the apolipoprotein E knockout mice and wild-type controls of similar age and genetic background. Apolipoprotein E knockout mice aged eight months demonstrated accurate spatial learning and normal neurological function. Synaptophysin and microtubule-associated protein 2 immunohistochemistry and electron microscopic analysis of these animals revealed that the hippocampal synaptic and dendritic densities were similar between genotypes. The induction and maintenance of kindled seizures and hippocampal long-term potentiation were indistinguishable between groups. Finally, unilateral entorhinal cortex lesions produced a marked loss of hippocampal synaptophysin immunoreactivity in both groups and a marked up-regulation of apolipoprotein E in the wild-type group. Both apolipoprotein E knockout and wild-type groups showed immunohistochemical evidence of reactive synaptogenesis, although the apolipoprotein E knockout group may have initially shown greater synaptic loss. It is suggested that either apolipoprotein E is of no importance in the maintenance of synaptic integrity and in processes of CNS plasticity and repair, or more likely, alternative (apolipo)proteins may compensate for the loss of apolipoprotein E in the knockout animals.

A narrow-linewidth all-solid-state laser system of low divergence with appreciable pulse-energy in the eyesafe region is required as a transmitter for the coherent wind lidar measurements from ground, air, and space-borne platform. Research efforts at NASA Langley Research Center (LaRC) were initiated to identify the laser material for optimum gain near eyesafe wavelength of 2-/spl mu/m. The Ho:Tm:YLF crystal, operating at 2.05 /spl mu/m, was selected as the laser gain medium based on a theoretical model developed at NASA/LaRC.

In many applications one is concerned with the approximation of functions from a finite set of given data sites with associated function values. We describe a construction of a hierarchy of triangulations which approximate the given data at varying levels of detail. Intermediate triangulations can be associated with a particular level of the hierarchy by considering their approximation errors. This paper presents a new data-dependent triangulation scheme for multi-valued scattered data in the plane. We perform piecewise linear approximation based on data-dependent triangulations. Our scheme preserves edges (discontinuities) that might exist in a given data set by placing vertices close to edges. We start with a coarse, data-dependent triangulation of the convex hull of the given data sites and subdivide triangles until the error of the piecewise linear approximation implied by a triangulation is smaller than some tolerance.

This study presents a comparison between two inhibitors of acetylcholinesterase, tacrine and E2020 (Donepezil), the 5-HT(3) receptor antagonist ondansetron, and the H(3) receptor antagonist thioperamide, in models of cholinergic function and cognition in male, Lister hooded rats. The cognitive tests used were an operant VI20 task, the delayed match to position task (short-term memory) and the 5-choice serial reaction time task (attention). Scopolamine (SCOP) (0.075mg/kg s.c.) was utilised in both the short-term memory and attention tasks to impair performance. Both tacrine (1-30mg/kg) and E2020 (1-10mg/kg) similarly produced overt cholinomimetic signs of likely central origin (hypothermia, tremor), although tacrine produced more profound peripheral cholinomimetic signs (miosis, secretory signs) than E2020. Tacrine (30mg/kg) and E2020 (10mg/kg) reduced the number of reinforcements gained in the VI20 schedule. Similarly, both drugs attenuated the SCOP-impairment models in the short-term memory and attention tasks (1-3mg/kg). Ondansetron (10ng/kg-1mg/kg) and thioperamide (0.2-10mg/kg) failed to elicit overt cholinomimetic signs or influence the number of food reinforcements gained in the VI20 schedule. Neither ondansetron nor thioperamide attenuated the SCOP-induced impairment in either cognitive task. From the present studies, both E2020 and tacrine showed a similar behavioural profile in the models used, although E2020 was about three times more potent. Furthermore, E2020 but not tacrine appeared to show some discrimination in eliciting central and peripheral cholinomimetic signs. The failure of ondansetron and thioperamide to reverse a SCOP-induced deficit in these models is discussed.

In order to validate the models for NO{sub x}, CO, and lean blowoff discussed in part 2 of this paper, the development of an experimental datum base was initiated. Experimental data were collected from an industrial, piloted-lean premixed, natural gas fired, can combustor rig. The experiments were designed in order to minimize testing cost and time. Independent variations of inlet pressure (8 to 14 atm), inlet temperature (550 to 750 K), and residence time (13 and 23 ms) were performed in order to gain insight into the sensitivity of the emissions levels to changes in combustor operating conditions.

1. The effects of the angiotensin antagonists GR117289, losartan and Sar1Ala8-angiotensin II on the ex vivo binding of [125I]-Sar1Ile8-angiotensin II to rat liver and cortex/hippocampus (Cx/H) membranes have been investigated. 2. GR117289 (0.1-30 mg kg-1, s.c., 2 h pretreatment) caused a dose-dependent reduction in [125I]-Sar1Ile8-angiotensin II binding to both liver and cortex/hippocampus membranes. 3. Administration of a submaximal dose of GR117289 (1 mg kg-1, s.c.) indicated that the peak inhibition of binding in the liver occurred within 0.5 h, whereas the peak inhibition of binding in the Cx/H occurred 2 h after drug treatment. 4. The effect of GR117289 was long lasting. Binding was still reduced in the Cx/H 48 h after drug treatment (10 mg kg-1, s.c.) but had returned to normal 72 h after drug treatment. In the liver binding was still reduced 72 h after treatment with the same dose. 5. Losartan (1-30 mg kg-1, s.c.) was equipotent with GR117289 in its ability to reduce liver binding, but was less effective at inhibiting binding to central receptors. 6. The non-peptide antagonist Sar1Ala8-angiotensin II (3 and 10 mg kg-1) reduced binding in the liver but not in the Cx/H membranes. 7. These results suggest that, unlike the peptide antagonist Sar1Ala8-angiotensin II, the non-peptide angiotensin antagonists, GR117289 and losartan, are able to cross the blood brain barrier and occupy central angiotensin II receptors.

1. This paper describes the effects of GR117289 (1-[[3-bromo-2-[2-(1H-tetrazol-5-yl)phenyl]-5-benzo-furanyl]methyl ]-2-butyl-4-chloro-1H-imidazole-5-carboxylic acid) at angiotensin receptors and binding sites in rabbit aorta, rat liver and bovine cerebellum preparations in vitro. 2. In rabbit isolated aortic strips, GR117289 (0.3, 1 and 3 nM) caused a concentration-related, insurmountable suppression of the concentration-response curve to angiotensin II (AII). When the contact time was increased, a greater degree of antagonism of AII was observed, suggesting that GR117289 is slow to reach equilibrium. A pKB of 9.8 +/- 0.1 was calculated for GR117289 after 3 h incubation. GR117289 (1 microM) did not affect contractile responses to phenylephrine or 5-hydroxytryptamine (5-HT) in the rabbit aorta. 3. GR117289 (1 nM) alone caused a marked suppression and a slight rightward displacement of the AII concentration-response curve. Co-incubation with the competitive, surmountable AT1 receptor antagonist, losartan (10 nM, 100 nM and 1 microM), resulted in a concentration-related upward and rightward displacement of the concentration-response curve to subsequently administered AII. In separate experiments in which preparations were pre-incubated with GR117289 (1 nM), subsequent addition of losartan (1 microM) for 2, 15 or 45 min caused a further, but similar, rightward displacement of the concentration-response curve to subsequently administered AII with a time-dependent increase in the maximum response.4. Suppression of All-induced contractile responses, caused by superfusion with GRI17289 (0.3, 1 or 3 nM) was not reversed by continuously washing the tissues for 3 h; in fact, the potency of GRI 17289 was slightly enhanced after this period.5. In rat liver membranes, GRI17289 was a potent competitor with [3H]-AII for AT, binding sites(pKi = 8.7 +/- 0.1) but in bovine cerebellum membranes, it was a very weak competitor for AT2 binding sites (pKi6). Pre-incubation of rat liver membranes with GRI17289 had little effect on its affinity(pKi = 9.1 +/- 0.21), but increasing the concentration of bovine serum albumen in the assay buffer from 0.001% to 0.1% w/v decreased affinity (pKi= 7.5 +/- 0.1).6. In saturation binding experiments in rat liver membranes, GRI 17289 (12 nM) increased the Kd of[3H]-AII from 0.28 +/- 0.06 nM to 0.37 +/- 0.02 nM, and decreased Bm. from 10.0 +/- 0.1 to 5.6 +/-0.3 fmol mg' tissue. In other experiments, GR1 17289 (1 jIM) did not alter the rate of dissociation of[3H]-AII from AT1 binding sites, following addition of excess unlabelled All.7. In rabbit aorta vascular smooth muscle membranes, GR1 17289 competed with ['25I]-Sar'1le8 All for binding to AT, binding sites. In the presence of 0.1% w/v bovine serum albumen, a pIC50 of 7.6 +/- 0.1 was calculated. Under the same conditions, but with rat liver membranes, a pIC50 of 7.8 +/- 0.1 was determined.8. Taken together, these results show that GRI17289 is a potent, specific, selective and insurmountable antagonist at angiotensin AT, receptors. Its profile in the rabbit aorta is consistent with the proposalthat GRI17289 is a slowly reversible (pseudo-irreversible) antagonist at these receptors.

1 The depolarizing responses to angiotensin II and angiotensin III of the rat superior cervical ganglion have been characterized in vitro, by the use of peptidase inhibitors, peptide and non-peptide antagonists and dithiothreitol (DTT). 2 Angiotensin II and III depolarized the ganglion in a concentration-related manner. Angiotensin II was approximately 30 fold more potent than angiotensin III. 3 The endopeptidase inhibitor, bacitracin, increased the potency of angiotensin II and III by approximately 4 and 20 fold respectively. The aminopeptidase inhibitor, amastatin, further increased the potency of angiotensin III (but not angiotensin II) by approximately 4 fold. In the presence of bacitracin and amastatin, angiotensin II and III were equipotent. 4 The peptide antagonist [Il7]angiotensin III (0.01–0.3 μm) produced a non-parallel rightward displacement of the angiotensin II concentration-response curve, with a suppression of the maximum response. The potency of [Ile7]angiotensin III was increased by bacitracin and amastatin. 5 The AT1-selective non-peptide antagonist losartan (DuP 753; 0.03 and 0.1 μm) produced a parallel rightward displacement of the angiotensin II concentration-response curve, with an apparent pKB of 8.3 ± 0.1. A higher concentration of losartan (0.3 μm) depressed the maximum agonist response by 32 ± 6.5%, possibly reflecting non-competitive behaviour of the antagonist. The potency of losartan was not influenced by bacitracin. 6 The AT2-selective non-peptide antagonist, PD123177 (3 μm) failed to antagonize the angiotensin II-induced depolarizations. 7 DTT (1 mm) produced a 22% reduction of the maximum response to angiotensin II. 8 We conclude that the angiotensin II-induced depolarizations of the rat superior cervical ganglion are mediated by angiotensin II receptors of the AT1 subclass. The ability of peptidase inhibitors to modify the potency of peptide agonists and antagonists highlights the difficulties associated with the use of peptide agents to characterize angiotensin II receptors in this preparation.

It is well established that inflammation and oxidative stress are key components of the pathology of Alzheimer's disease (AD), but how early in the pathological cascade these processes are involved or which specific molecular components are key, has not been fully elucidated. This paper describes the pharmacological approach to understand the molecular components of inflammation and oxidative stress on the activation of microglial cells and neuronal cell viability. We have shown that activation of microglia with the 42-amino-acid form of the ϐ-amyloid peptide (Aϐ42) activates the production of cyclooxygenase-2, the inducible form of nitric oxide synthase and tumour necrosis factor-α and there appears to be little interactive feedback between these three mediators. Moreover, we explore the effects of a series of salen-manganese complexes, EUK-8, -134 and -189, which are known to possess both superoxide and catalase activity. These compounds are able to protect cells from insults produced by hydrogen peroxide or peroxynitrite. Moreover, EUK-134 was also able to limit the output of prostaglandin E2 from activated microglial cells. The mechanisms underlying these effects are discussed. Together, these data support a pivotal role for oxidative stress and inflammation as key mediators of the pathological cascade in AD and provide some ideas about possible therapeutic targets.

Accumulation by Penicillium notatum of the non-metabolized glucose analogue, 3- O -methyld-[U- 14 C] glucose, was concentrative and did not require phosphorylation. The uptake of a further glucose analogue, 2-deoxy-D-glucose, was also concentrative but since it was partially metabolized it was unsuitable for kinetic studies. Uptake of 3- O -methyl-D-glucose by vegetative and Ca 2+ -induced mycelium was inhibited by proton conductors and respiratory inhibitors, and competitively inhibited by D-glucose with an apparent K i of 94 μM. Sugar accumulation exhibited saturation kinetics at low substrate concentration ( ca 1.25 mM) with an apparent K m of 100 μm for vegetative cells with reduced affinity for 3- O -methyl-D-glucose being displayed in the presence of Ca 2+ as indicated by an apparent K m of 308 μM. However, the V max values for both types of mycelium were similar. Sugar accumulation followed the pattern of a pump-and-leak system but with modifications at higher concentrations within the range 0.01–200mM. Whilst the steady-state concentration within cells increased with increasing concentration in the medium it was not proportional to that outside beyond 1.25 mM. At sugar concentrations in the medium in excess of 20 mM, vegetative cells showed relative exclusion of substrate with increasing concentrations, but Ca 2+ modified this phenomenon. Results are discussed in relation to theoretical models of sugar transport and the role of Ca 2+ in sugar regulation during conidiation.

Concentrations of adenine and pyridine nucleotides and the associated charge values were examined in extracts of mycelium of Penicillium notatum during vegetative growth and reproductive development promoted by the addition of Ca2+ (10 mmol dm-3). The significant increase in adenylate energy charge promoted by Ca2+ was due to a fall in intracellular AMP and a concomitant rise in ATP concentration. Intracellular concentrations of NADH and NAD fell within 1 h of the addition of Ca2+. The catabolic reduction charge was unchanged by Ca2+ whilst the anabolic reduction charge increased in Ca2+-induced mycelium due to lowered intracellular NADP concentration. Reduced concentration of NADPH in Ca2+-induced mycelium, relative to the vegetative controls, lowered the phosphorylated nucleotide fraction. The results are discussed in relation to metabolic economy during morphogenesis in P. notatum.

Submerged cultures of Penicillium notatum on a modified Czapek-Dox medium, containing sucrose or glucose, were characterized by high intracellular and extracellular glucose oxidase activity, heavy gluconate production and failure to sporulate. Addition of Ca 2+ to cultures within 48 h of inoculation promoted sporulation, greatly reduced the rate of increase of glucose oxidase activity in the biomass and medium and, in turn, the production of extracellular gluconate. Gluconate media supported slow growth of the fungus and a low level of sporulatiom even in the absence of Ca 2+ but the addition of Ca 2+ enhanced spore formation. Fructose media, on which glucose oxidase and gluconate were not produced, supported Ca 2+ -induced sporulation which was, as with sucrose and glucose, entirely dependent upon the presence of Ca 2+ within 48 h of inoculation; thereafter the Ca 2+ effect was not manifested. The possible role of gluconate as a regulator of sporulation is discussed, along with views that ageing of components of the biomass may exert a primary effect upon the sites of the Ca 2+ trigger.

The reactions between aqueous iodic acid and some lanthanide oxides have been investigated. TbO 2 and Tb 4 O 7 both yield a compound Tb IV O 2 ·2 Tb III ( IO 3 ) 3 · nH 2 O . Pr 6 O 11 and PrO 2 also yield mixed oxidation state phases but no reproducible compounds were obtained. Infrared and u.v./visible spectra and magnetic moment measurements are reported.

The complexes formed between La 3+ , Sm 3+ , Gd 3+ , and Er 3+ , and tricarballylic acid have been investigated by potentiometry in 0.100 molar aqueous KCl at 25.00 °C. Formation constants are reported for the species LnHT and LnT. These constants show a similar variation from metal to metal to that found for the lanthanide acetate complexes.