bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

SummaryObjective  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

SummaryThin 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

SummaryWe 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

SummaryMost 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

SummaryThin, 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

AbstractLeptin 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

AbstractIndividual 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

AbstractWe 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

AbstractCentral 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

AbstractEmpirical 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

AbstractCognitive 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

AbstractIn 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

SummaryMore 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.