bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visual function at school age in children with neonatal encephalopathy and low Apgar scores
Authors: Reading Richard 
Published: December 2004

Mercuri E,
Anker S,
Guzzetta A,
Barnett AL,
Haataja L,
Rutherford M,
Cowan F,
Dubowitz L,
Braddick O &
Atkinson J.

(
2004
)
Archives of Disease in Childhood Fetal and Neonatal Edition
,
89
,
F258
–
262
.
ObjectiveTo assess different aspects of visual function at school age in children who suffered from neonatal encephalopathy.MethodsThirty‐nine full term infants with neonatal encephalopathy, low Apgar scores, and early neonatal imaging were studied using a battery of tests assessing different aspects of visual function (crowding acuity, stereopsis, visual fields) at school age. The results were compared with brain magnetic resonance imaging (MRI) findings and, when possible, with the results of the assessment of visual function performed at 5 and 12 months, available in 24 of the 39 children examined at school age.ResultsSixteen of the 39 children (41%) had abnormal results at school age in at least one of the visual tests used. Seven of these 16 were untestable on all tests. The remaining 23 children (59%) had normal results.ConclusionsThe presence and severity of visual impairment was related to the severity of brain lesions. Moderate or severe basal ganglia lesions and severe white matter changes were always associated with abnormal visual function. Infants with normal MRI, minimal basal ganglia lesions and minimal or moderate white matter involvement tended to have normal vision. It was also found that the assessment of visual function performed in the first year was a reliable indicator of visual function at school age. With two exceptions, the results on the 5 months visual assessment were predictive of visual outcome at school age. In the remaining two cases, a normal visual outcome at 5 years was associated with visual abnormalities at 5 months but these had already normalized by the age of 1 year.
The effects of a double blind, placebo controlled, artificial food colourings and benzoate preservative challenge on hyperactivity in a general population sample of preschool children
Authors: Reading Richard 
Published: December 2004

.

Bateman B,
Warner JO,
Hutchinson E,
Dean T,
Rowlandson P,
Gant C,
Grundy J,
Fitzgerald C &
Stevenson J.

(
2004
)
Archives of Disease in Childhood
,
89
,
506
–
511
.
AimsTo determine whether artificial food colourings and a preservative in the diet of 3 years old children in the general population influence hyperactive behaviour.MethodsA sample of 1873 children were screened in their fourth year for the presence of hyperactivity at baseline (HA), of whom 1246 had skin prick tests to identify atopy (AT). Children were selected to form the following groups: HA/AT, not‐HA/AT, HA/not‐AT and not‐HA/not‐AT (n = 277). After baseline assessment, children were subjected to a diet eliminating artificial colourings and benzoate preservatives for 1 week; in the subsequent 3 weeks within subject double blind crossover study they received, in random order, periods of dietary challenge with a drink containing artificial colourings (20 mg daily) and sodium benzoate (45 mg daily) (active period), or a placebo mixture, supplementary to their diet. Behaviour was assessed by a tester blind to dietary status and by parents’ ratings.ResultsThere were significant reductions in hyperactive behaviour during the withdrawal phase. Furthermore, there were significantly greater increases in hyperactive behaviour during the active than the placebo period based on parental reports. These effects were not influenced by the presence or absence of hyperactivity, nor by the presence or absence of atopy. There were no significant differences detected based on objective testing in the clinic.ConclusionsThere is a general adverse effect of artificial food colouring and benzoate preservatives on the behaviour of 3 years old children which is detectable by parents but not by a simple clinic assessment. Subgroups are not made more vulnerable to this effect by their prior levels of hyperactivity or by atopy.
Growth hormone receptor expression and function in pituitary adenomas
Authors: Clausen Lene R. , Kristiansen Mikkel T. , Rasmussen Lars M. , Billestrup Nils , Blaabjerg Ole , Ledet Thomas , Jørgensen Jens O. L. 
Published: December 2004

Summaryobjective and design  Hypopituitarism, in particular GH deficiency, is prevalent in patients with clinically nonfunctioning pituitary adenomas (NFPAs) both before and after surgery. The factors regulating the growth of pituitary adenomas in general and residual tumour tissue in particular are not fully characterized, and the effect of GH and IGF‐I on human pituitary cell proliferation has not previously been reported. In NFPA tissue from 14 patients we evaluated GH receptor (GHR) expression and signal transduction, and the effect of GH and IGF‐I exposure on cell proliferation and hormone secretion in vitro.measurements  Tissue samples from 14 NFPAs were investigated. Expression of GHR in tissue samples was assessed by reverse transcription polymerase chain reaction (RT‐PCR). Six tumours were immunostained with a GHR antibody. In the cell cultures, STAT5 (signal transducer and activator of transcription 5) phosphorylation was measured by Western blot analysis as an index of GHR signalling; cell proliferation was evaluated by [H3]‐thymidine incorporation and glycoprotein hormone production analysed by radioimmunoassay (RIA).results  All adenomas investigated expressed the GHR, but there was no detection of STAT5 phosphorylation. Overall, GH and IGF‐I administration did not significantly stimulate cell proliferation in vitro, although some individual adenomas exhibited a proliferative response to various extents. GH also did not significantly influence glycoprotein hormone secretion in vitro.conclusion  GH receptors are expressed in human pituitary adenoma cells but their functional role is uncertain. GH and IGF‐I do not consistently influence the proliferation of cultured pituitary adenoma cells.
Species identification of Chilean Artemia populations based on mitochondrial DNA RFLP analysis
Authors: Gajardo Gonzalo , Crespo Julio , Triantafyllidis Alexander , Tzika Athanasia , Baxevanis Athanasios D. , Kappas Ilias , Abatzopoulos Theodore J. 
Published: December 2004

AbstractAim  Two species of the brine shrimp, namely Artemia franciscana Kellogg and A. persimilis Piccinelli and Prosdocimi, inhabit Chile. Most studies so far have shown that A. franciscana is the most widely distributed species in Chile, with A. persimilis present only in Chilean Patagonia. In general, there is good agreement between morphological and genetic comparisons of Chilean populations with respect to species discrimination. However, a number of results indicate an overlap with some populations tending to diverge from A. franciscana and/or resembling A. persimilis. Prior to the mid 90's the use of DNA markers in Artemia was rather limited, despite their successful application in numerous other species. In this study, we investigate whether the conclusions drawn from traditional comparative tools are congruent with the pattern of genetic divergence depicted by DNA analysis at the mitochondrial level.Location  Eight sites in Chile and two reference samples of A. franciscana and A. persimilis from San Francisco Bay (USA) and Buenos Aires (Argentina), respectively.Methods  Restriction fragment length polymorphism (RFLP) analysis of a 535 bp segment of the mitochondrial 16S rRNA gene with nine restriction enzymes in 240 individuals.Results  No haplotype was shared between the two species. Five restriction enzymes produced species‐specific patterns, enabling the unambiguous assignment of populations to species. Very high (100%) bootstrap values supported the clustering of haplotypes in two groups corresponding to the two species. The two species were clearly differentiated with average sequence divergence of 12.3%. High genetic differentiation was also found among con‐specific populations of A. franciscana with an FST estimate of 91%.Main conclusions  The mitochondrial DNA (mtDNA) results of this study show a broadly similar pattern to those of previous allozyme and nuclear DNA analyses, with the two New World species appearing as highly divergent. The presence of A. persimilis in southern Chile (Chilean Patagonia) was confirmed. Hence, a species previously regarded as geographically restricted mainly to Argentina, appears to have expanded its range. Populations of A. franciscana appear highly structured with a level of inter‐population genetic differentiation much higher for mtDNA than previously reported with allozymes. Clustering of these populations does not follow a clear geographic pattern. The identification of population‐specific genetic markers for A. persimilis and A. franciscana will help to tackle further aspects of the speciation patterns of these species.
Effect of residual endogenous insulin secretion on the abnormal oxytocin response to hypoglycaemia in insulin‐dependent diabetes
Authors: VOLPI R. , CHIODERA P. , CAPRETTI L. , CAFFARRI G. , GIULIANI N. , CAIAZZA A. , COIRO V. 
Published: December 2004

Abstract. Volpi R, Chiodera P, Capretti L, Caffarri G, Giuliani N, Caiazza A, Coiro V (University of Parma, Hospital of Codogno, Hospital of Guastalla, Hospital of Fidenza, Italy). Effect of residual endogenous insulin secretion on the abnormal oxytocin response to hypoglycaemia in insulin‐dependent diabetics. J Intern Med 1998; 244: 43–8.ObjectivesArginine‐vasopressin (AVP) and oxytocin (OT) secretions are abnormally stimulated by hypoglycaemia in patients with IDDM. Since previous studies showed that AVP secretion is influenced by the persistence of residual endogenous insulin secretion, we wondered whether this factor also regulates OT secretion.DesignCase‐control study: the OT response to insulin‐induced hypoglycaemia was measured in normal and diabetic patients with or without residual endogenous insulin secretion.SubjectsTen normal male subjects, 10 C‐peptide positive (CpP) and 11 C‐peptide negative (CpN) male diabetic patients.TestsPreliminary studies: plasma C‐peptide levels were measured after intravenous administration of 1 mg glucagon.Insulin tolerance test (ITT): diabetics were studied after optimization of their metabolic status by 3 days of treatment with constant subcutaneous insulin infusion. CpP and CpN diabetics and normal controls were tested with an intravenous administration of 0.15 IU per kg body weight insulin. Blood samples for OT assay were taken just before the rapid injection of insulin (time 0) and at time 15, 30, 45 and 60 min.ResultsThe basal concentrations of OT were similar in all groups. Insulin induced a similar hypoglycaemic nadir in all groups at 30 min, even though diabetic groups showed a delayed recovery in blood glucose levels. The glycaemic pattern was similar in all diabetic patients. Hypoglycaemia‐induced OT rise was significantly higher in the two diabetic groups than in the normal group. However, CpN patients showed significantly higher OT increments than CpP subjects.ConclusionsThese data indicate that a residual endogenous insulin secretion exerts a partial protective action against the hypothalamic‐pituitary disorder affecting the OT secretory system in IDDM.
Rejection of Conspecific Eggs in Chaffinches: The Effect of Age and Clutch Characteristics
Authors: Stokke Bård G. , Rudolfsen Geir , Moksnes Arne , Røskaft Eivin 
Published: December 2004

AbstractPrevious experimental studies have found that the majority of chaffinches,Fringilla coelebs, are able to reject both non‐mimetic and mimetic cuckoo eggs and also non‐mimetic conspecific eggs. However, interestingly the frequency of rejecters of moderately mimetic conspecific eggs has been found to be only approx. 50%. We examined the possibility that acceptors of moderately mimetic conspecific eggs are first time breeders, because these individuals may lack the experience needed to reject eggs that deviate only slightly from their own eggs. Older individuals, with good knowledge of their own egg appearance, should therefore reject such eggs. We also examined the possibility that acceptors of moderately mimetic eggs have a higher intraclutch variation in egg appearance, which makes it more difficult to recognize such eggs when compared with rejecters. We obtained no support for any age‐specific pattern in rejection behaviour. Furthermore, there was no relationship between age and intraclutch variation, or intraclutch variation and rejection behaviour. As there is no evidence of intraspecific brood parasitism in this species, the rejection of any foreign eggs is most probably an adaptation to past cuckoo,Cuculus canorus, parasitism. Acceptance of good and moderately mimetic conspecific eggs is probably due to cognitive limitations, because evolution of a more fine‐tuned recognition ability is unnecessary in the absence of intraspecific brood parasitism.
Both ETA and ETB receptors are involved in mitogen‐activated protein kinase activation and DNA synthesis of astrocytes: study using ETB receptor‐deficient rats (aganglionosis rats)
Authors: Sasaki Yukio , Hori Seiji , Oda Kyoko , Okada Toshikazu , Takimoto Misato 
Published: December 2004

AbstractEndothelin (ET) is known to be a potent mitogen in astrocytes. However, the contribution and signalling pathway of ETA and/or ETB receptor to the proliferation of astrocytes remain unclear. We investigated ET‐induced DNA synthesis in astrocytes using ETB receptor‐deficient mutant rats (aganglionosis rats: sl/sl). Western blotting with anti‐ET receptor subtype‐specific antibodies and Scatchard analysis of binding revealed that ETB receptor expression in astrocytes depended on gene dosage (+/+: sl/+: sl/sl = 2: 1: 0), whereas ETA receptor expression was unchanged among the three genotypes. ET‐1 (10 nm) stimulated [3H]thymidine incorporation and mitogen‐activated protein kinase (MAP kinase) activity not only in +/+ via both ETA and ETB receptors, but also in sl/sl astrocytes via ETA receptor with about half the extent of those observed in +/+ astrocytes. Treatment with pertussis toxin (PTX) suppressed the ET‐1‐induced increases in the incorporation and MAP kinase activity in +/+, but not sl/sl astrocytes, indicating that the ETB receptor‐, but not the ETA receptor‐, mediated pathway to DNA synthesis involves PTX‐sensitive G proteins, e.g. Gi and/or Go (Gi/o). In +/+ astrocytes, ET‐1 (1 nm) stimulated cAMP accumulation, and the ETB receptor‐selective agonist IRL 1620 (1 nm) suppressed 10 μm forskolin‐induced cAMP accumulation, suggesting Gs coupling to the ETA receptor and Gi/o coupling to the ETB receptor. On the other hand, ET‐1 did not increase cAMP accumulation in sl/sl astrocytes, although ET‐1 (1 nm) suppressed the forskolin‐induced response, suggesting Gi/o coupling to the ETA receptor. Our results suggest the possibility that the selectivity of G protein for ETA receptor is changed from Gs to Gi/o in ETB receptor‐deficient astrocytes.
Blockade of M2‐like muscarinic receptors enhances long‐term potentiation at corticostriatal synapses
Authors: Calabresi Paolo , Centonze Diego , Gubellini Paolo , Pisani Antonio , Bernardi Giorgio 
Published: December 2004

AbstractAcetylcholine (ACh) exerts a crucial role in learning and memory. The striatum contains the highest concentration of this transmitter in the brain. This structure expresses two different forms of synaptic plasticity, long‐term depression (LTD) and long‐term potentiation (LTP), which might contribute to the storage of motor skills and some cognitive processes. We have investigated the role of M2‐like muscarinic receptors in striatal LTP by utilizing intracellular recordings in vitro from a rat corticostriatal slice preparation. Methoctramine (250 nm), an antagonist of M2‐like muscarinic receptors, enhanced striatal LTP induced in the absence of external magnesium (Mg2+) by high‐frequency stimulation (HFS) of corticostriatal fibres. Methoctramine did not affect the amplitude of excitatory postsynaptic potentials (EPSPs) when bath applied either before or after the conditioning tetanus suggesting that a critical increase of ACh concentrations is produced only during HFS. Methoctramine per se failed to enhance the NMDA‐mediated EPSPs recorded in the absence of external Mg2+ and in the presence of 10 μm CNQX. Methoctramine antagonized the presynaptic inhibitory action of neostigmine, an inhibitor of ACh‐esterase, and oxotremorine, an agonist of M2‐like muscarinic receptors. These data indicate that the activation of M2‐like muscarinic receptors exerts a negative influence on striatal LTP, probably by reducing the release of glutamate from corticostriatal fibres and they suggest a complex modulatory effect of ACh in striatal synaptic plasticity.
Cortical inhibitory circuits in eye‐movement generation
Authors: Schiller Peter H. , Tehovnik Edward J. 
Published: December 2004

AbstractThe role inhibitory circuits play in target selection with saccadic eye movements was examined in area V1, the frontal eye fields (FEF) and the lateral intraparietal sulcus (LIP) of the Rhesus Macaque monkey by making local infusions of the GABA agonist muscimol and antagonist bicuculline. In V1, both agents greatly interfered with target selection and visual discrimination of stimuli placed into the receptive field of the affected neurons. In the FEF, bicuculline facilitated target selection without affecting visual discrimination and generated many spontaneous saccades. Muscimol in the FEF interfered with saccadic eye‐movement generation. In the LIP, bicuculline was ineffective and muscimol had only a small effect. These findings suggest that in the FEF GABAergic inhibitory circuits play a central role in eye‐movement generation whereas in V1 these circuits are essential for visual analysis. Inhibitory circuits in the LIP do not appear to play a central role in target selection and in visual discrimination.
Reduced expression of a novel µ‐opioid receptor (MOR) subtype MOR‐1B in CXBK mice: Implications of MOR‐1B in the expression of MOR‐mediated responses
Authors: Narita Minoru , Imai Satoshi , Ozaki Satoru , Suzuki Masami , Narita Michiko , Suzuki Tsutomu 
Published: December 2004

AbstractA novel µ‐opioid receptor (MOR) subtype, named MOR‐1B, derived from alternatively spliced variants of MOR gene, has been isolated from the rat brain. Here we found for the first time that CXBK recombinant‐inbred mice display a significant reduction in the expression of MOR‐1B mRNA in the brain as compared to that in their progenitor C57BL/6 mice. In contrast, the expression level of MOR‐1 mRNA in the brain of CXBK mice was similar to that found in C57BL/6 mice. Furthermore, relatively lower levels of MOR‐1B immunoreactivity were detected in the periaqueductal grey matter (PAG) of CXBK mice than that observed in C57BL/6 mice. To investigate further the possible changes in MOR function to activate G‐proteins under the condition of a reduced MOR‐1B expression, the guanosine‐5′‐o‐(3‐[35S]thio)triphosphate ([35S]GTPγS) binding assay was performed. We found that the increased level of [35S]GTPγS bindings to whole brain membranes induced by a selective MOR agonist endomorphin‐1 was significantly decreased in CXBK mice, indicating that CXBK strain can be classified as MOR‐1B‐knockdown mice. We next investigated whether intracerebroventricular (i.c.v.) pretreatment with an antisence oligodeoxynucleotide against exon 5 of MOR gene (MOR‐1B) could affect the endomorphin‐1‐induced supraspinal antinociception. The i.c.v. pretreatment with antisence oligodeoxynucleotide against MOR‐1B produced a significant reduction in the i.c.v.‐administered endomorphin‐1‐induced antinociceptive effect. The present data provide first evidence that a lack of MOR‐1B expression may, at least in part, contribute to the reduced sensitivity to MOR agonists in CXBK mice, and MOR‐1B may play a potential role in the MOR‐mediated supraspinal antinociception.
Transcranial magnetic stimulation of the human frontal eye field facilitates visual awareness
Authors: Grosbras Marie‐Hélène , Paus Tomáš 
Published: December 2004

AbstractWhat are the brain mechanisms allowing a stimulus to enter our awareness? Some theories suggest that this process engages resources overlapping with those required for action control, but experimental support for these ideas is still required. Here, we investigated whether the human frontal eye field (FEF), an area known to control eye movements, is involved in visual awareness. Volunteers participated in a backward masking task in which they were able to detect a target in a small proportion of trials. We observed that a single pulse of transcranial magnetic stimulation applied over the FEF shortly before the target's onset facilitated visual sensitivity; subjects were able to detect an otherwise subliminal object. These results show that modulating the neuronal activity of the FEF can enhance visual detection, thereby yielding new insights into the neural basis of visual awareness.
Glutamate receptor binding in the frontal cortex and dorsal striatum of aged rats with impaired attentional set‐shifting
Authors: Nicolle Michelle M. , Baxter Mark G. 
Published: December 2004

AbstractAged Long–Evans rats exhibit deficits in attentional set shifting, an aspect of executive function, relative to adult rats. Impairments in set shifting and spatial learning are uncorrelated in aged rats, indicating a possible dissociation of the effects of ageing in prefrontal versus hippocampal systems. Ionotropic glutamate receptor binding was assessed using an in vitro autoradiography method in young and aged rats. The rats had been tested on a set‐shifting task that measured attentional set shifts and reversal learning, as well as in a spatial learning task in the Morris water maze. [3H]Kainate, [3H]AMPA and NMDA‐displaceable [3H]glutamate receptor binding were quantified in orbital cortex, cingulate cortex, medial frontal cortex, dorsolateral and dorsomedial striatum. Age‐related decreases in [3H]kainate binding were apparent in all regions measured. Similarly, NMDA‐displaceable [3H]glutamate binding was decreased in the aged rats in all the regions measured except for the medial frontal area where no age effects were observed. [3H]AMPA receptor binding was preserved with age in all the regions measured. Lower levels of [3H]kainate binding in the cingulate cortex were significantly correlated with poorer set‐shifting performance, whereas higher levels of NMDA binding in the dorsomedial striatum were correlated with poorer set‐shifting performance. There were no significant correlations between the levels of ionotropic glutamate receptors and performance in the reversal task or spatial learning in the Morris water maze. These results indicate that age‐related behavioural deficits in attentional set shifting are selectively associated with neurobiological alterations in the cingulate cortex and dorsomedial striatum.