bluuebunny/crossref_metadata_2025 huggingface dataset:
ECSES – examining crystal structures using `e-science': a demonstrator employing web and grid services to enhance user participation in crystallographic experiments
Authors: Coles Simon J. , Frey Jeremy G. , Hursthouse Michael B. , Light Mark E. , Meacham Ken E. , Marvin Darren J. , Surridge Mike
Published: September 2005

An application of e-science methodology and grid networking technology is presented that opens up new possibilities to enhance the operation of large high-throughput service-crystallography facilities, exemplified by the UK National Crystallography Service (NCS). A seamless distributed computing approach is used to provide remote secure visualization, monitoring and interaction with the laboratory and the diffraction experiment, supervision and input to the data workup and analysis processes, and to enable dissemination and further use of the resulting structural data. The architecture of the system is based on web and grid services (in particular the use ofGlobus, v1.1.4), which provide a secure environment for two-way information flow and communication between the service users and operators. This capability will enhance operations of instrument and software automation by providing more efficient use of the resources, increasing the throughput of samples and enabling interactions with distributed chemistry information databases, computational services and networks. The viability of these interactions is assessed and directions for future crystallography services suggested. The setup would be equally applicable to protein or powder crystallography services.
Duodenal secretion in humans mediated by the EP4 receptor subtype
Authors: Larsen R. , Hansen M. B. , Bindslev N.
Published: September 2005

Aim:  Assessment of functional EP receptor subtypes involved in PGE2‐induced secretion in human duodenum. The spectrum of activities by PGE2 in mammals, including cytoprotective bicarbonate secretion in duodenum, is mediated through four G protein‐coupled receptor subtypes (EP1–EP4).

Methods:  Biopsies from the second part of duodenum from patients undergoing endoscopy were mounted in modified Ussing chambers. Basal and stimulated short circuit current (SCC) and slope conductance (SG) were measured. Dose–response relations for PGE2 and subtype receptors EP1/EP3 (sulprostone), EP2 (butaprost), and EP4 (1‐OH PGE1) were assessed by cumulated doses of single agonists.

Results:  PGE2 caused a dose‐dependent increase in SCC, maximum 101 ± 20 μA cm−2 with an EC50 of 35.6 ± 5.8 nm (n = 3). Likewise 1‐OH PGE1 caused a dose‐dependent SCC increase, maximum 63.3 ± 28.6 μA cm−2 with an EC50 of 56.7 ± 7.2 nm (n = 3). 1‐OH PGE1 at 500 nm increased SCC by 18.0 ± 3.0 μA cm−2 (n = 10) and SG by 2.9 ± 0.4 mS cm−2 (n = 6). Sulprostone (n = 6) and butaprost (n = 6) had no effects on SCC or SG. SCC was inhibited 31.4 ± 13.2% (n = 10) by bumetanide (25 μm serosa) and 18.6 ± 5.8% (n = 10) by acetazolamide (250 μm lumen). Diphenylamine‐2‐carboxylate (DPC) (250 μm mucosa) and SITS (10 μm mucosa) had almost no effect.

Conclusions:  Effects of PGE2 on secretion in the second part of human duodenum is mediated through the EP4 receptor and not through EP1, EP2, or EP3.
Initial anatomic investigations of the I‐gel airway: a novel supraglottic airway without inflatable cuff*
Authors: Levitan R. M. , Kinkle W. C.
Published: September 2005

The I‐gel airway is a novel supraglottic airway that uses an anatomically designed mask made of a gel‐like thermoplastic elastomer. We studied the positioning and mechanics of this new device in 65 non‐embalmed cadavers with 73 endoscopies (eight had repeat insertion), 16 neck dissections, and six neck radiographs. A full view of the glottis (percentage of glottic opening score 100%) occurred in 44/73 insertions, whereas only 3/73 insertions had epiglottis‐only views. Including the eight repeat insertions with a different size, a glottic opening score of > 50% was obtained in all 65 cadavers. The mean percentage of glottic opening score for the 73 insertions was 82% (95% confidence interval 75–89%). In each of the neck dissections and radiographs the bowl of the device covered the laryngeal inlet. We found that the I‐gel effectively conformed to the perilaryngeal anatomy despite the lack of an inflatable cuff and it consistently achieved proper positioning for supraglottic ventilation.
Effects of music on target‐controlled infusion of propofol requirements during combined spinal‐epidural anaesthesia*
Authors: Zhang X. W. , Fan Y. , Manyande A. , Tian Y. K. , Yin P.
Published: September 2005

The sedative effects of music were evaluated using the bispectral index (BIS) during target‐controlled infusion (TCI) propofol. A total of 110 women undergoing hysterectomy were randomly allocated to receive either music or no music. Propofol was administered using target‐controlled infusion and the concentration adjusted gradually to achieve an observer's assessment of alertness/sedation (OAA/S) score of 3 intra‐operatively. The haemodynamic and bispectral index values during the sedation phase were recorded. Interleukin‐6 was evaluated before, immediately after and 1 h following intervention. The music group had a significant reduction in mean (SD) induction time of sedation: 12 (12) min vs. 18 (12) min, p < 0.01; propofol target concentration: 1.6 (0.3) μg.ml−1 vs. 2.4 (0.4) μg.ml−1, p < 0.0001; intra‐operative amount of propofol: 171 (98) mg vs. 251 (92) mg, p < 0.0001; and significantly higher levels of satisfaction with their peri‐operative care: 9.6 (0.6) compared to the control group: 8.1 (1.0), p < 0.0001. No other differences were found. The results show the influence of music on the induction time of sedation, concentration and level of propofol during surgery, and suggest sedative benefits of music.
Percutaneous cervical pharyngostomy: a traditional technique revisited
Authors: Jones T. M. , Bodenham A. R.
Published: September 2005

Enteral tube feeding is widely used in intensive care units, high dependency units and general wards. In some patients, an adequate intake is not maintained because patients cannot tolerate the tube. Insertion of an enteral feeding tube via a pharyngostomy is simple and potentially more easily tolerated. We describe our experience with three critically ill patients, using disposable vascular access equipment and a dilational technique. All three patients received markedly increased nutrition, but one patient suffered haemorrhagic complications.
Hyperprolactinaemia in 271 women: up to three decades of clinical follow‐up
Authors: Berinder Katarina , Stackenäs Ingela , Akre Olof , Hirschberg Angelica Lindén , Hulting Anna‐Lena
Published: September 2005

Objective  To characterize women with hyperprolactinaemia at diagnosis and to assess the effect of treatment after long duration of the disease.

Design  Retrospective chart review.

Patients and measurements  Two hundred and seventy‐one women with hyperprolactinaemia at the Karolinska University Hospital, Stockholm, Sweden between 1974 and 2002 were evaluated retrospectively. Criterion for inclusion was elevated S‐PRL (≥ 20 µg/l) found on at least two occasions. Secondary hyperprolactinaemia was excluded. The patients were followed for a median time period of 111 (6–348) months. Two hundred and forty patients were treated with dopamine agonists, 17 underwent surgery, seven received radiotherapy and seven were followed without treatment.

Results  Mean age at diagnosis was 31 (± 9·5) years and median PRL level was 72 (25–3500) µg/l. Menstrual disturbances were present in 87% of the women of reproductive age and 47% had galactorrhoea. Microadenomas were found in 63%, macroadenomas in 8% and idiopathic hyperprolactinaemia in 29%. Patients with menstrual disturbances had higher PRL levels than women with normal menstrual function (P < 0·001). We found no differences in PRL levels between patients with or without galactorrhoea (P = 0·578). At the end of clinical follow‐up, menstrual cycle was normalized in 94% and galactorrhoea disappeared in 94%. In the medically treated patients, median PRL levels decreased from 70 (25–3100) to 13 (0–89) µg/l, (P < 0·0001). Normalization of PRL level was achieved in 71% of the patients and 80% showed a total or partial degree of tumour shrinkage. In the surgically treated patients, 53% had normal PRL levels without medication at follow‐up.

Conclusion  Medical treatment was effective in correcting hypogonadism, normalizing PRL levels and reducing tumour size in the majority of the patients after short‐term treatment and also in the long run. However, the possibility of transsphenoidal surgery in specific cases must be considered.
Thyroid function and morphology in patients affected by Williams syndrome
Authors: Stagi Stefano , Bindi Giuseppe , Neri Anna Silvia , Lapi Elisabetta , Losi Stefania , Jenuso Rita , Salti Roberto , Chiarelli Francesco
Published: September 2005

Objective  To evaluate the prevalence of abnormalities of thyroid function and morphology in a cohort of patients with Williams syndrome (WS).

Methods  Serum concentrations of free‐T3, free‐T4, TSH, thyroperoxidase antibodies (TPOA) and thyroglobulin antibodies (TgA), as well as ultrasonographic data, of 20 patients with WS (12 females and eight males), aged 1·7–34·9 years, were evaluated.

Results  Three cases (15%) of subclinical hypothyroidism were identified. Overt hypothyroidism was diagnosed in two cases (10%). Thyroid antibodies were negative in all patients. Fourteen patients (70%) showed thyroid hypoplasia involving the entire gland. In these patients, the left thyroid lobe appeared usually, but not significantly, reduced compared with the right thyroid lobe. One patient (5%) showed thyroid hemiagenesis. Only five patients (25%) showed a thyroid with normal volume, and of these five, one patient showed marked thyroid hypoplasia of the left lobe. In all WS patients with diagnosis of subclinical or overt hypothyroidism, thyroid hypoplasia was detected. No cases of subclinical or overt hypothyroidism were found in WS with normal thyroid volume.

Conclusions  This study confirms the presence of alterations of thyroid function in WS and also suggests the frequent occurrence of abnormalities of thyroid morphology in these patients. Patients with WS should be monitored for thyroid function and a thyroid ultrasound screening should be considered, especially in those patients with changes in thyroid function.
Optical patterning in azobenzene polymer films
Authors: STILLER B. , GEUE T. , MORAWETZ K. , SAPHIANNIKOVA M.
Published: September 2005

Thin azobenzene polymer films show a very unusual property, namely optically induced material transport. The underlying physics for this phenomenon has not yet been thoroughly explained. Nevertheless, this effect enables one to inscribe different patterns onto film surfaces, including one‐ and two‐dimensional periodic structures. Typical sizes of such structures are of the order of micrometers, i.e. related to the interference pattern made by the laser used for optical excitation. In this study we have measured the mechanical properties of one‐ and two‐dimensional gratings, with a high lateral resolution, using force–distance curves and pulse force mode of the atomic force microscope. We also report on the generation of considerably finer structures, with a typical size of 100 nm, which were inscribed onto the polymer surface by the tip of a scanning near‐field optical microscope used as an optical pen. Such inscription not only opens new application possibilities but also gives deeper insight into the fundamentals physics underlying optically induced material transport.
Core‐shell CdS/Cd(OH)2 quantum dots: synthesis and bioconjugation to target red cells antigens
Authors: ALBUQUERQUE DE FARIAS P. M. , SAEGESSER SANTOS B. , DUARTE DE MENEZES F. , DE CARVALHO FERREIRA R. , DE LOURDES BARJAS‐CASTRO M. , CASTRO V. , MOURA LIMA P. R. , FONTES A. , L. CESAR C.
Published: September 2005

We report a new and efficient methodology of labelling red blood cells, in order to investigate the expression of anti‐A antigen, employing luminescent semiconductor nanocrystals. Highly luminescent and stable core‐shell cadmium sulphide/cadmium hydroxide [CdS/CdS(OH)2] colloidal particles were obtained in the nanometre size range. The surface of these particles was characterized by using a monoclonal anti‐A antibody via a one‐step glutaraldehyde cross‐linking procedure, followed by conjugation of the particles to red cells of blood groups A+, and O+. Laser scanning confocal microscopy images indicated that after conjugation for 30 min, A+ and erythrocytes presented different patterns of dual bright emission whereas the O+ group cells showed no emission. We suggest that this labelling procedure may be applied as a quantitative tool to investigate the distribution and expression of alloantigen in red blood cells.
A simple and practical method to acquire geometrically correct images with resonant scanning‐based line scanning in a custom‐built video‐rate laser scanning microscope
Authors: LEYBAERT L. , DE MEYER A. , MABILDE C. , SANDERSON M. J.
Published: September 2005

Most currently available confocal or two‐photon laser scanning microscopes (LSMs) allow acquisition rates of the order of 1–5 images s−1, which is too slow to fully resolve dynamic changes in intracellular messenger concentration in living cells or tissues. Several technologies exist to obtain faster imaging rates, either in the video‐rate range (30 images s−1) or beyond, but the most versatile technology available today is based on resonant scanners for horizontal line scanning. These scanning devices have several advantages over designs based on acousto‐optical deflectors or Nipkow discs, but a drawback is that the scanning pattern is not a linear but rather a sinusoidal function of time. This puts additional constraints on the hardware necessary to read‐in the image data flow, one of which is the generation of a pixel clock that varies in frequency with the position of the pixel on the scanned line. We describe a practical solution to obtain a variable pixel clock add‐on that is easy to build and is easy to integrate into a custom‐built LSM based on resonant scanning technology. In addition, we discuss some important hardware and software design aspects that simplify the construction of a resonant scanning‐based LSM for high‐speed, high‐resolution imaging. Finally, we demonstrate that the microscope can be used to resolve calcium puffs triggered by photolytically increasing the intracellular concentration of inositol trisphosphate.
Characterization of sectioning fluorescence microscopy with thin uniform fluorescent layers: Sectioned Imaging Property or SIPcharts
Authors: BRAKENHOFF G. J. , WURPEL G. W. H. , JALINK K. , OOMEN L. , BROCKS L. , ZWIER J. M.
Published: September 2005

Thin, uniformly fluorescing reference layers can be used to characterize the imaging conditions in confocal, or more general, sectioning microscopy. Through‐focus datasets of such layers obtained by standard microscope routines provide the basis for the approach. A set of parameters derived from these datasets is developed for defining a number of relevant sectioned imaging properties. The main characteristics of a particular imaging situation can then be summarized in a Sectioned Imaging Property‐chart or SIPchart. We propose the use of such charts for the characterization of imaging properties in confocal and multiphoton microscopy. As such, they can be the basis for comparison of sectioned imaging condition characteristics, quality control, maintenance or reproduction of sectioned imaging conditions and other applications. Such charts could prove useful in documenting the more relevant properties of the instrumentation used in microscopy studies. The method carries the potential to provide the basis for a general characterization of sectioned imaging conditions as the layers employed can be characterized and fabricated to standard specifications. A limited number of such thin, uniformly fluorescing layers is available from our group for this purpose. Extension of the method to multiphoton microscopy is discussed.
Hypothalamic Phosphatidylinositol 3‐Kinase‐Phosphodiesterase 3B‐Cyclic AMP Pathway of Leptin Signalling is Impaired Following Chronic Central Leptin Infusion
Authors: Sahu A. , Metlakunta A. S.
Published: September 2005

Leptin signalling in the hypothalamus is critical for the maintenance of normal body weight. Although hyperleptinaemia in obese people suggests a state of leptin resistance, and diet‐induced obesity in rodents is associated with central leptin resistance, the underlying mechanisms remain unclear. Recent evidence suggests that, in addition to the signal transducer and activator of the transcription‐3 (STAT3) pathway, leptin action is critical for energy homeostasis through an insulin‐like signalling pathway involving an increase in phosphatidylinositol 3‐kinase (PI3K) and phosphodiesterase 3B (PDE3B) activities and reduction in cyclic AMP (cAMP) levels in the hypothalamus. Here, we show that chronic central leptin (160 ng/h) infusion, which resulted in the development of resistance to the satiety action of leptin, impaired the PI3K‐PDE3B‐cAMP pathway of leptin signalling in the hypothalamus in that PI3K and PDE3B activities were increased and cAMP levels were decreased in the hypothalamus on day 2 of leptin infusion but remained unchanged on day 16. Additionally, induction of tyrosyl phosphorylation of insulin receptor substrate‐1 observed on day 2 was not evident on day 16 of leptin infusion. By contrast, signalling through the STAT3‐pathway remained activated in the hypothalamus throughout 16 days of leptin infusion. These findings show a differential response in PI3K‐PDE3B‐cAMP (impaired) and STAT3 (up‐regulated) pathways to chronic central leptin infusion, and suggest a selective resistance in the PI3K‐PDE3B‐cAMP pathway of leptin signalling following a chronic increase in hypothalamic leptin tone attained by central infusion of this peptide hormone.
Improved survival after in‐hospital cardiac arrest outside critical care areas
Authors: Skrifvars M. B. , Saarinen K. , Ikola K. , Kuisma M.
Published: September 2005

Background:  The in‐hospital Utstein Guidelines may be used to evaluate resuscitation strategies. This study utilized the Utstein template prospectively to examine changes in outcome and outcome‐related factors after resuscitation outside critical care areas over a 10‐year period.

Methods:  Seinäjoki Central Hospital (460 beds) is a secondary hospital in Finland with acute care activities. In 1993, the in‐hospital cardiac arrest management was remodelled; an intensive care unit‐based resuscitation team was formed and prospective data collection began (modified according to the Utstein Guidelines in 1997). An analysis of resuscitation attempts outside critical care areas between 1993 and 2002 was performed. To monitor developments, the patients were divided into two groups (first period, 1993–97; second period, 1998–2002). Variables independently associated with survival were identified using multiple logistic regression analysis.

Results:  During the 10‐year period, resuscitation was attempted in 183 patients. Survival to discharge was 6% during the first period and 16% during the second (P = 0.048). The corresponding figures for survival at 1 year from the event were 3% and 10% (P = 0.064). Independent predictors of survival were ventricular fibrillation or ventricular tachycardia as the initial rhythm [odds ratio (OR), 9.8; confidence interval (CI), 3.2–30.3] and cardiac arrest occurring during the second period (OR, 3.3; CI, 1.1–10.1).

Conclusion:  Prospective Utstein style data collection proved to be a valuable tool for the evaluation of management and outcome following in‐hospital cardiac arrest. Increased survival was seen over 10 years outside critical care areas. Organizational changes, including cardiopulmonary resuscitation training for ward personnel and standardized resuscitation management, may have contributed to this change.
Achromatic Plumage Reflectance, Social Dominance and Female Mate Preference in Black‐Capped Chickadees (Poecile atricapillus)
Authors: Woodcock Elisabeth A. , Rathburn Melanie K. , Ratcliffe Laurene M.
Published: September 2005

Individual variation in achromatic plumage reflectance of male Black‐capped Chickadees (Poecile atricapillus) is correlated with social rank and reproductive success, suggesting it may play an important role in sexual signaling. We asked whether female chickadees could assess male quality based on plumage, in the absence of information about relative social dominance. Sexually mature but inexperienced females captured during the pair formation period in late fall and early winter were presented with a choice of two unfamiliar, sexually experienced males in separate compartments of an outdoor mate choice arena. Following each preference trial, we released the males into a single compartment and scored their pairwise dominance interactions. In 10 of 11 trials, females spent significantly more time with the male subsequently identified as dominant, despite not witnessing the males interact. Spectral analysis of male plumage reflectance revealed that UV‐chroma of dark body regions (bib, cap and mantle) was significantly greater in dominant, preferred males and that dominant, preferred males had significantly brighter white cheek patches. There were no differences in vocalization rates of preferred and non‐preferred males. These results show that female chickadees can rapidly assess unfamiliar males based on visual cues, and suggest that variation in achromatic plumage functions in sexual signaling.
Shoals Receive more Attacks from the Wolf‐Fish (Hoplias malabaricusBloch, 1794)
Authors: Botham Marc S. , Krause Jens
Published: September 2005

We investigated whether the piscivorous wolf‐fish,Hoplias malabaricus(Bloch, 1794), showed preferences for attacking a ‘straggler’ or a shoal using guppies,Poecilia reticulata(Peters, 1860), as prey. Predators should show a preference to attack single prey items rather than grouped prey to overcome the confusion effect, which has been shown to negatively affect their capture success. However, they may attack groups more frequently because they are more likely to detect them because of their greater conspicuousness. In our study we looked at predator choice for grouped or single prey and whether this was affected by larger shoals being more conspicuous. We offeredHopliasbinary choices of a single guppy (straggler) and shoals of 2, 6 and 10 fish.Hopliaspreferred to attack the shoal over the straggler with regards to both frequency of attacks (initial and subsequent) and attack duration. The implications for predator–prey interactions of such a preference are discussed.
Anxiety but not arousal increases 5‐hydroxytryptamine release in the rat ventral hippocampus in vivo
Authors: Rex A. , Voigt J. P. , Fink H.
Published: September 2005

Central serotonin [5‐hydroxytryptamine (5‐HT)] is involved in the aetiology of numerous disease states, including depression and anxiety disorders. Studies have shown that exposure of rats to animal tests of anxiety increases extracellular 5‐HT in the cortex or hippocampus determined by in vivo microdialysis. To discriminate whether this increase is caused by the aversive conditions of an animal test for anxiety or by an unconditioned stressor evoking mainly arousal, the present study investigates the effects of an unconditioned acoustic stimulus and exposure to the elevated plus maze (X‐maze), respectively, on the release of 5‐HT in the ventral hippocampus compared with hippocampal 5‐HT release in the home cage and in a non‐aversive unfamiliar environment in freely moving rats. Our results showed a distinct pattern of 5‐HT release in the ventral hippocampus depending on the stimulus used. Exposure to the X‐maze for 20 min was accompanied by an ‘anxious’ behaviour in the rats and increased extracellular 5‐HT to 165% of basal release, whereas exposure to a less aversive ‘deactivated’ plus maze (115 ± 6%) or to white noise for 20 min in the familiar surroundings of the home cage (98 ± 6%) did not change hippocampal 5‐HT release significantly, despite similar behavioural activation indicated by increased locomotor activity. While both the X‐maze and white noise may model anxiety and stress to a certain extent, it seems that the X‐maze is more aversive. The results suggest a close relationship between anxiety‐related behaviour, but not arousal/non‐specific behavioural activation, and 5‐HT release in the ventral hippocampus.
Functional MRI of facial emotion recognition deficits in schizophrenia and their electrophysiological correlates
Authors: Johnston Patrick J. , Stojanov Wendy , Devir Holly , Schall Ulrich
Published: September 2005

Empirical evidence suggests impaired facial emotion recognition in schizophrenia. However, the nature of this deficit is the subject of ongoing research. The current study tested the hypothesis that a generalized deficit at an early stage of face‐specific processing (i.e. putatively subserved by the fusiform gyrus) accounts for impaired facial emotion recognition in schizophrenia as opposed to the Negative Emotion‐specific Deficit Model, which suggests impaired facial information processing at subsequent stages. Event‐related potentials (ERPs) were recorded from 11 schizophrenia patients and 15 matched controls while performing a gender discrimination and a facial emotion recognition task. Significant reduction of the face‐specific vertex positive potential (VPP) at a peak latency of 165 ms was confirmed in schizophrenia subjects whereas their early visual processing, as indexed by P1, was found to be intact. Attenuated VPP was found to correlate with subsequent P3 amplitude reduction and to predict accuracy when performing a facial emotion discrimination task. A subset of ten schizophrenia patients and ten matched healthy control subjects also performed similar tasks in the magnetic resonance imaging scanner. Patients showed reduced blood oxygenation level‐dependent (BOLD) activation in the fusiform, inferior frontal, middle temporal and middle occipital gyrus as well as in the amygdala. Correlation analyses revealed that VPP and the subsequent P3a ERP components predict fusiform gyrus BOLD activation. These results suggest that problems in facial affect recognition in schizophrenia may represent flow‐on effects of a generalized deficit in early visual processing.
Dual tasking, gait rhythmicity, and Parkinson's disease: Which aspects of gait are attention demanding?
Authors: Yogev Galit , Giladi Nir , Peretz Chava , Springer Shmuel , Simon Ely S. , Hausdorff Jeffrey M.
Published: September 2005

Cognitive function and the performance of a secondary, dual task may affect certain aspects of gait, but the relationships between cognitive function and gait are not well understood. To better understand the motor control of gait and the relationship between cognitive function and gait, we studied cognitive function and the effects of different types of dual tasking on the gait of patients with Parkinson's disease (PD) and controls, contrasting measures of gait automaticity and rhythmicity with other features. Patients with idiopathic PD (n = 30; mean age 71.8 year) with moderate disease severity (Hoehn and Yahr Stage 2–3) were compared to age and gender‐matched healthy controls (n = 28). Memory and executive function were also assessed. In both groups, gait speed decreased in response to dual tasking, in a parallel fashion. For the PD group only, gait variability increased compared to usual walking. Executive function was significantly worse in the PD group, while memory was not different in the two groups. Executive function measures were significantly correlated with gait variability during dual tasking, but not during usual walking. These findings demonstrate that regulation of gait variability and rhythmicity is apparently an automatic process that does not demand attention in healthy adults. In patients with PD, however, this ability becomes attention‐demanding and worsens when subjects perform secondary tasks. Moreover, the associations between executive function and gait variability suggest that a decline in executive function in PD may exacerbate the effects of dual tasking on gait, potentially increasing fall risk.
Serotonergic regulation of calcium‐activated potassium currents in rodent prefrontal cortex
Authors: Villalobos Claudio , Beique Jean‐Claude , Gingrich Jay A. , Andrade Rodrigo
Published: September 2005

In spite of a growing understanding of the actions of 5‐hydroxytryptamine (5‐HT) in the prefrontal cortex, the specific cellular mechanism used by 5‐HT in this region remains poorly understood. Previous studies have shown that 5‐HT inhibits the afterhyperpolarization that follows a burst of spikes in pyramidal neurons. In the present study, we have used whole cell recordings in rat and mouse brain slices to re‐examine this phenomenon with special emphasis on identifying the 5‐HT receptor subtypes mediating this effect. Layer V pyramidal neurons display complex afterhyperpolarizations that are mediated predominantly by calcium‐activated potassium channels and involve two distinct currents known as medium afterhyperpolarizating current and slow afterhyperpolarizating current (IsAHP). Administration of 5‐HT reduced the current underlying these afterhyperpolarizations by selectively inhibiting IsAHP. Pharmacological analysis of this response indicates that the main receptor responsible for this inhibition belongs to the 5‐HT2A subtype. Thus, α‐methyl‐5‐HT and 2,5‐dimethoxy‐4‐bromoamphetamine (DOB) mimic the effect of 5‐HT and the effect of these agonists is blocked by MDL 100 907. Similarly, administration of α‐methyl‐5‐HT is without effect in slices derived from 5‐HT2A receptor knockout mice. However, 5‐HT2A receptor blockade only partially suppressed the ability of 5‐HT to inhibit IsAHP. This suggests the involvement of at least one more receptor subtype in this response. Consistent with this idea, administration of 5‐carboxyamido‐tryptamine, an agonist exhibiting no detectable affinity for 5‐HT2A receptors, was also capable of suppressing IsAHP. These results identify 5‐HT2A receptors as being primarily involved in mediating the 5‐HT‐induced inhibition of IsAHP in prefrontal cortex, while also recognizing a contribution by an additional 5‐HT receptor subtype.
Identifying pioneer bacterial species responsible for biofouling membrane bioreactors
Authors: Zhang Kai , Choi Heyok , Dionysiou Dionysios D. , Sorial George A. , Oerther Daniel B.
Published: September 2005

More effective control of membrane biofouling in membrane bioreactors (MBRs) lies in the fundamental understanding of the pioneer microorganisms responsible for surface colonization that leads to biofilm formation. In this study, the composition of the planktonic and sessile microbial communities inhabiting four laboratory‐scale MBR systems were compared using amplified ribosomal DNA restriction analysis (ARDRA) and 16S ribosomal DNA gene sequencing. The ARDRA results suggest that the microbial communities on membrane surfaces could be very different from the ones in the suspended biomass. Phylogenetic analysis based on the 16S rRNA gene sequences provided a list of bacteria that might be the pioneers of surface colonization on microfiltration membranes. The results further suggested that research on the mechanisms of cell attachment in such an engineering environment could be critical for future development of appropriate biofouling control strategies.
Fungi associated with hair roots of Rhododendron lochiae (Ericaceae) in an Australian tropical cloud forest revealed by culturing and culture‐independent molecular methods
Authors: Bougoure Damian S. , Cairney John W. G.
Published: September 2005

The culturable fungal assemblage associated with hair roots of Rhododendron lochiae (Ericaceae) from a tropical cloud forest in Queensland, Australia was investigated using rDNA internal transcribed spacer (ITS) restriction fragment length polymorphisms (RFLPs) and sequence analysis, and the abilities of the fungi to form ericoid mycorrhizas were tested. DNA was further extracted directly from hair roots and partial fungal ITS products compared with those from the cultured isolate assemblage using denaturing gradient gel electrophoresis (DGGE). A range of ericoid mycorrhizal and non‐mycorrhizal fungi was identified using both approaches, with ericoid mycorrhizal fungi found to be taxonomically similar to those associated with Ericaceae in temperate habitats worldwide. Both approaches identified several unique fungi and, although most of the abundant RFLP types identified in the cultured fungal assemblage were also present in DGGE profiles of DNA extracted directly from roots, one the most commonly isolated RFLP types, a putative Xylariaceae taxon, was absent. The data suggest that a combination of culturing and culture‐independent approaches may be more efficacious than either method individually.
Reproductive condition of Akodon montensis Thomas and Bolomys lasiurus (Lund) (Rodentia, Muridae) based on histological and histometric analyses of testes and external characteristics of gonads
Authors: Couto D. , Talamoni S. A.
Published: September 2005

The reproductive activity of two species of wild rodents was studied in the Serra do Rola‐Moça State Park (PERM), in the state of Minas Gerais, Brazil. From October 1998 to October 1999 specimens of Akodon montensis (Thomas 1913) were captured in an area of seasonal semi‐deciduous forest, while specimens of Bolomys lasiurus (Lund 1840) were captured in a cerrado area (a savannah‐like grassland). The determination of the reproductive condition was based on histological and histometric analyses of testes and external characteristics of gonads. The volume of the testes, diameter of the seminiferous tubules and depth of the seminiferous epithelium were measured. Akodon montensis showed a seasonal annual reproductive cycle divided into four stages (recrudescence, activity or proliferation, regression and rest) with the reproductive activity mainly occurring during the rainy season. In contrast, B. lasiurus presented reproductive activity during almost the whole year. For both species the volume of the testes was an effective indicator of their reproductive condition. We suggest that the histological and histometric analysis of the gonads of males, together with the observations of external characteristics of gonads of males and females, may assist in identifying the reproductive condition of these animals.
Differentiation of the reproductive tract between dominant and subordinate workers in the Japanese queenless ant Diacamma sp.
Authors: Allard D. , Ito F. , Gobin B. , Tsuji K. , Billen J.
Published: September 2005

In queenless ants, gamergates (mated egg‐laying workers) fulfil the reproductive task normally reserved for the queen. Every worker is a potential gamergate, thus we expect pronounced conflicts over sexual reproduction within their colonies. In the queenless ant genus Diacamma, gamergates inhibit nest mates from mating by aggressively removing (‘mutilating’) a pair of small appendages on the thorax, termed gemmae, shortly after eclosion. Dissection and serial sectioning of the reproductive tracts of both mutilated and unmutilated individuals of Diacamma sp. from Japan at different ages revealed that mutilation inhibits the development of the bursa copulatrix and the spermatheca, two structures fundamental for sexual reproduction. The precursor of the bursa copulatrix develops into a fully functional structure in unmutilated individuals, whereas it degenerates irreversibly in mutilated callows. Experimental manipulations showed that the removal of the gemmae is not the sole factor regulating this development. The spermathecal epithelium and accessory spermathecal gland of unmutilated individuals are thicker than that of mutilated individuals, indicating a higher degree of activity in the former. Mutilated females are therefore left incapable of copulating and less competent for long‐time sperm storage.
Knock‐down of POSH expression is neuroprotective through down‐regulating activation of the MLK3–MKK4–JNK pathway following cerebral ischaemia in the rat hippocampal CA1 subfield
Authors: Zhang Quan‐Guang , Wang Rui‐Min , Yin Xiao‐Hui , Pan Jing , Xu Tian‐Le , Zhang Guang‐Yi
Published: September 2005

We investigated the expression and subcellular localization of the multidomain protein POSH (plenty of SH3s) by immunohistochemistry and western blot analysis, as well as its role in the selective activation of mixed‐lineage kinases (MLKs) 3, MAP kinase kinase (MKK) 4, c‐Jun N‐terminal kinases (JNKs) and the c‐Jun signalling cascade in the rat hippocampal CA1 region following cerebral ischaemia. Our results indicated that the cytosol immunoreactivity of POSH was strong in the CA1‐CA3 pyramidal cell but weak in the DG granule cell of the rat hippocampus both in sham control and after reperfusion. Co‐immunoprecipitation experiments showed that the interactions of MLK3, MKK4 and phospho‐JNKs with POSH were persistently enhanced during the early (30 min) and the later reperfusion period (from 1 to 3 days) compared with sham controls. Consistently, MLK3–MKK4–JNK activation was rapidly increased with peaks both at 30 min and 3 days of reperfusion. Intracerebroventricular infusion of POSH antisense oligodeoxynucleotides (AS‐ODNs) not only significantly reduced the protein level of POSH, markedly decreased its interactions with MLK3, MKK4 and phospho‐JNKs, but also attenuated the activation of the JNK signalling pathway. In addition, infusion of POSH AS‐ODNs significantly increased the neuronal density in the CA1 region at 5 days of reperfusion. Our results suggest that POSH might serve as a scaffold mediating JNK signalling activation in the hippocampal CA1 region following cerebral ischaemia, and POSH AS‐ODNs exerts its protective effects on ischaemic injury through a mechanism of inhibition of the MLK3–MKK4–JNK signalling pathway, involving c‐Jun and caspase 3 activation.
The scaffolding protein PSD‐95 interacts with the glycine transporter GLYT1 and impairs its internalization
Authors: Cubelos Beatriz , González‐González Inmaculada M. , Giménez Cecilio , Zafra Francisco
Published: September 2005

Recent evidence indicates that the glycine transporter‐1 (GLYT1) plays a role in regulation of NMDA receptor function through tight control of glycine concentration in its surrounding medium. Immunohistochemical studies have demonstrated that, as well as being found in glial cells, GLYT1 is also associated with the pre‐ and postsynaptic aspects of glutamatergic synapses. In this article, we describe the interaction between GLYT1 and PSD‐95 in the rat brain, PSD‐95 being a scaffolding protein that participates in the organization of glutamatergic synapses. Mutational analysis reveals that the C‐terminal sequence of GLYT1 (–SRI) is necessary for the transporter to interact with the PDZ domains I and II of PSD‐95. This C‐terminal tripeptide motif also seems to be involved in the trafficking of GLYT1 to the membrane, although this process does not involve PDZ proteins. GLYT1 is able to recruit PSD‐95 to the plasma membrane, but it does not affect its clustering. However, the interaction stabilizes this transporter at the plasma membrane, blocking its internalization and producing a significant increase in the Vmax of glycine uptake. We hypothesize that PSD‐95 might act as a scaffold for GLYT1 and NMDA receptors, allowing GLYT1 to regulate the concentrations of glycine in the micro‐environment of NMDA receptors.
Dopamine neurons express multiple isoforms of the nuclear receptor nurr1 with diminished transcriptional activity
Authors: Michelhaugh Sharon K. , Vaitkevicius Henrikas , Wang Jun , Bouhamdan Mohamad , Krieg Alexys R. , Walker Jennifer L. , Mendiratta Varsha , Bannon Michael J.
Published: September 2005

Nurr1 (NR4A2) is an orphan nuclear receptor required for the development and maintenance of the dopaminergic phenotype in neurons of the ventral midbrain. This study demonstrates that multiple splice variants of nurr1 are produced in rat and human dopamine neurons. Formed by alternative RNA splicing in exon 7, nurr1a has a truncated carboxy‐terminus, nurr1b has an internal deletion in the ligand‐binding domain and nurr1c, newly identified in this study, has a novel carboxy‐terminus produced by a frame shift downstream of the splice junction. Alternative RNA splicing in exon 3 produces the isoform known as the transcriptionally‐inducible nuclear receptor (TINUR), lacking the amino‐terminus. Nurr2 and the newly identified nurr2c are produced by utilization of both exon 3 and exon 7 alternative splice sites. In rat midbrain, variants other than full‐length nurr1 constitute 20–35% of NR4A2 transcripts. Transfection studies in dopaminergic SK‐N‐AS cells demonstrate that nurr1a, nurr1b, nurr1c and TINUR have significantly reduced transcriptional activities compared with full‐length nurr1, while nurr2 and nurr2c are inactive. Furthermore, in these experiments, nurr2 and nurr2c both act as dominant negatives. Production of these nurr1 variants in vivo as demonstrated here could represent a novel regulatory mechanism of nurr1 transcriptional activity and therefore, dopaminergic phenotype.
Apparent effect on blood pressure is only partly responsible for the risk reduction due to antihypertensive treatments
Authors: Boissel Jean‐Pierre , Gueyffier François , Boutitie Florent , Pocock Stuart , Fagard Robert
Published: September 2005

The mechanism of risk reduction obtained by blood pressure‐lowering pharmacological treatment remains unclear. We explored the amount of risk reduction attributable to the apparent effect of antihypertensive medicines on blood pressure by using the capture approach. Five randomized, placebo or nil controlled trials with a total of 28 997 subjects and 1935 cardiovascular fatal or non‐fatal events from the INDANA database met the eligibility criteria. Computations were performed on the original individual records using multiple Cox's proportional hazard regression models designed for meeting the assumed treatment mode of action and comparing relevant assumptions. For coronary event, the results are inconclusive essentially because the risk reduction is mild. However, for stroke the risk reduction adjusted for baseline risk factors is 34% (P < 0.0001). The part explained by the effect of treatment on systolic blood pressure is 49% of this reduction, with 95% confidence interval not including 100%. This result suggests that the apparent effect on blood pressure is not the only cause of stroke risk reduction in hypertensive subjects submitted to an antihypertensive medicine.
Exercise training protects the renal circulation against high glucose challenge
Authors: De Moraes Roger , Gioseffi Giovanni , Lopes Nuno do Nascimento , Gomes Marilia Brito , Nóbrega Antonio Claudio Lucas , Tibiriçá Eduardo
Published: September 2005

It has been shown previously that high glucose causes direct and acute endothelial dysfunction in non‐diabetic isolated rabbit kidney. This study assessed whether exercise training is able to maintain normal renal vascular endothelial function despite high glucose exposure. Animals were pen confined (SED) or treadmill trained over a 12‐week period (ExT). Kidneys isolated from SED and ExT rabbits were continuously perfused ex vivo during 3 h with Krebs–Henseleit solutions containing normal (5.5 mm) or high (15 mm) concentrations of d‐glucose. In the SED 5.5 group, acetylcholine (ACh) induced dose‐related vasodilator responses, reaching the maximum of 41 ± 2% (n = 10; P < 0.05). In the kidneys perfused with high concentrations of glucose (SED 15), endothelium‐dependent vasodilation was significantly blunted. Maximal relaxation in the presence of 15 mm glucose was of 19 ± 2%, which was significantly different from the SED 5.5 group (41 ± 2%, n = 10, P < 0.01). In the ExT 5.5 group, ACh‐induced vasodilation was significantly enhanced when compared with the SED 5.5 group, reaching the maximum of (52 ± 2%, n = 10, P < 0.05). Moreover, the exposure of the renal circulation of ExT animals to high glucose did not change endothelium‐dependent vasodilation induced by ACh (46 ± 3%, n = 6), when compared with the ExT 5.5 group. Finally, exercise training prevented the deleterious effects of high glucose on endothelial‐dependent renal vasodilation (SED 15: 19 ± 2% vs. ExT 15: 46 ± 3%; P < 0.05). It is concluded that exercise training protects the rabbit renal circulation against endothelial dysfunction elicited by acute exposure to moderately elevated glucose levels, corresponding to the postprandial glycemia of diabetes type 2 patients under treatment. The enhanced renal vasodilator reserve elicited by exercise training turns out to be a response that protects the kidney from the deleterious effects of glycemic peaks.
Investigating the protective effects of aged garlic extract on cyclosporin‐induced nephrotoxicity in rats
Authors: Wongmekiat Orawan , Thamprasert Kamthorn
Published: September 2005

Cyclosporin A (CsA) nephrotoxicity has been described in solid organ recipients and in the patients who were treated for autoimmune diseases. Reactive oxygen species‐induced oxidative stress and lipid peroxidations are implicated in the pathophysiology of CsA‐induced renal injury. Aged garlic extract (AGE) has been reported to exhibit potent antioxidative and free radical scavenging abilities in various disease conditions. The present study was designed to investigate whether AGE could possibly have a protective effect against nephrotoxicity induced by CsA. Male Wistar rats were treated orally with CsA (50 mg/kg/day), CsA + AGE (0.25, 0.5, 1, and 2 g/kg/day started 3 days before the first dose of CsA), or the vehicle of CsA for a period of 10 days. Blood urea nitrogen, serum creatinine, creatinine clearance, and renal histopathological changes were evaluated after 24 h of the last treatment. CsA caused an increase in blood urea nitrogen and serum creatinine by 117 and 100%, respectively, whereas it decreased creatinine clearance by 78% compared with the vehicle‐treated rats (all P < 0.001). AGE treatment (0.5, 1 and 2 g/kg) significantly protected animals against CsA‐induced biochemical changes, albeit blood urea nitrogen and creatinine clearance in the 0.5 g/kg AGE treated‐animals were only partially restored. Kidney sections taken from CsA‐treated rats showed severe vacuolations and tubular necrosis. These histopathological changes were markedly improved by pretreatment of rats with AGE at the dose of 0.5–2 g/kg. The results indicate that AGE ameliorates renal dysfunction and morphological changes induced by CsA, and imply that it could be a beneficial remedy for attenuating the CsA nephrotoxicity.
Public Sector Decentralisation: Measurement Concepts and Recent International Trends*
Authors: Stegarescu Dan
Published: September 2005

This paper deals with the problems encountered in defining and measuring the degree of fiscal decentralisation. Drawing on a recent analytical framework of the OECD, different measures of tax autonomy and revenue decentralisation are presented which consider the tax‐raising powers of sub‐central governments. Taking account of changes in the assignment of decision‐making competencies over the course of time, new time series of annual data on the degree of fiscal decentralisation are provided for 23 OECD countries over the period between 1965 and 2001. It is shown that common measures usually employed tend to overestimate the extent of fiscal decentralisation considerably. Evidence is also provided of increasing fiscal decentralisation in a majority of OECD countries during the last three decades.