bluuebunny/crossref_metadata_2025 huggingface dataset:
Mycoplasmas and Ureaplasmas as Neonatal Pathogens
Authors: Waites Ken B. , Katz Brenda , Schelonka Robert L.
Published: October 2005

The genital mycoplasmas represent a complex and unique group of microorganisms that have been associated with a wide array of infectious diseases in adults and infants. The lack of conclusive knowledge regarding the pathogenic potential ofMycoplasmaandUreaplasmaspp. in many conditions is due to a general unfamiliarity of physicians and microbiology laboratories with their fastidious growth requirements, leading to difficulty in their detection; their high prevalence in healthy persons; the poor design of research studies attempting to base association with disease on the mere presence of the organisms in the lower urogenital tract; the failure to consider multifactorial aspects of diseases; and considering these genital mycoplasmas only as a last resort. The situation is now changing because of a greater appreciation of the genital mycoplasmas as perinatal pathogens and improvements in laboratory detection, particularly with regard to the development of powerful molecular nucleic acid amplification tests. This review summarizes the epidemiology of genital mycoplasmas as causes of neonatal infections and premature birth; evidence linking ureaplasmas with bronchopulmonary dysplasia; recent changes in the taxonomy of the genusUreaplasma; the neonatal host response to mycoplasma and ureaplasma infections; advances in laboratory detection, including molecular methods; and therapeutic considerations for treatment of systemic diseases.
NON-UNIQUENESS AND RADIUS OF CYCLIC UNARY NFAs
Authors: DOMARATZKI MICHAEL , ELLUL KEITH , SHALLIT JEFFREY , WANG MING-WEI
Published: October 2005

In this paper we study some properties of cyclic unary regular languages. We find a connection between the uniqueness of the minimal NFA for certain cyclic unary regular languages and a Diophantine equation studied by Sylvester.

We also obtain some results on the radius of unary languages. We show that the nondeterministic radius of a cyclic unary regular language L is not necessarily obtained by any of the minimal NFAs for L. We give a class of examples which demonstrates that the nondeterministic radius of a regular language cannot necessarily even be approximated by the minimal radius of its minimal NFAs.
RESTRICTED SETS OF TRAJECTORIES AND DECIDABILITY OF SHUFFLE DECOMPOSITIONS
Authors: DOMARATZKI MICHAEL , SALOMAA KAI
Published: October 2005

The decidability of the shuffle decomposition problem for regular languages is a long standing open question. We consider decompositions of regular languages with respect to shuffle along a regular set of trajectories and obtain positive decidability results for restricted classes of trajectories. Also we consider decompositions of unary regular languages. Finally, we establish in the spirit of the Dassow-Hinz undecidability result an undecidability result for regular languages shuffled along a fixed linear context-free set of trajectories.
NON-RECURSIVE TRADE-OFFS FOR TWO-WAY MACHINES
Authors: KAPOUTSIS CHRISTOS
Published: October 2005

If the machines of some type A have enough resources to (i) solve problems that no machine of type B can solve, and (ii) simulate any unary two-way deterministic finite automaton that has access to a linearly-bounded counter, then typically no recursive function can upper bound the increase in the size of description when a machine of type A is replaced by an equivalent machine of type B.
ON THE DESCRIPTIONAL COMPLEXITY OF METALINEAR CD GRAMMAR SYSTEMS
Authors: SUNCKEL BETTINA
Published: October 2005

Metalinear CD grammar systems are context-free CD grammar systems where each component consists of metalinear productions. The maximal number of nonterminals in all starting productions is referred to as the width of a CD grammar system. It is shown that between the class of CD grammar systems of width m + 1 and of width m there are savings concerning the size of the grammar system not bounded by any recursive function. This is called a non-recursive trade-off. Furthermore, it is proven that there are non-recursive trade-offs between the class of metalinear CD grammar systems of width m and the class of (2m - 1)-linear context-free grammars. In addition, some decidability results are presented.
DYNAMICAL SYSTEMS IN GRAPH C*-ALGEBRAS
Authors: JEONG JA A , PARK GI HYUN
Published: October 2005

Let E be a row finite directed graph with no sinks and (XE, σE) the one-sided edge shift space. Then the graph C*-algebra C*(E) contains the commutative algebra C0(XE). Moreover if E is locally finite so that the canonical completely positive map ϕE on C*(E) is well-defined, ϕE|C0(XE) coincides with the *-homomorphism [Formula: see text]. In this paper we first show that if two edge shift spaces (XE, σE) and (XF, σF) are topologically conjugate, there is an isomorphism of C*(E) onto C*(F), and if the graphs are locally finite the isomorphism transforms ϕE|C0(XE) onto ϕF|C0(XF), which has been known for Cuntz–Krieger algebras. Let ht(ϕE) be Voiculescu–Brown topological entropy of ϕE. In case E is finite, it is well-known that the values ht(ϕE), [Formula: see text], hl(E) and hb(E) all coincide, where [Formula: see text] is the AF core of C*(E) and hl(E), hb(E) are the loop, block entropies of E respectively. If E is irreducible and infinite, [Formula: see text] has been known recently, and here we show that [Formula: see text], where Et is the transposed graph of E. Also some dynamical systems related with AF subalgebras [Formula: see text] of [Formula: see text] are examined to prove that [Formula: see text] for each vertex v.
SOME RESULTS ON HARMONIC MAPS FOR FINSLER MANIFOLDS
Authors: HE QUN , SHEN YI-BING
Published: October 2005

By simplifying the first and the second variation formulas of the energy functional and generalizing the Weitzenböck formula, we study the stability and the rigidity of harmonic maps between Finsler manifolds. It is proved that any nondegenerate harmonic map from a compact Einstein Riemannian manifold with nonnegative scalar curvature to a Berwald manifold with nonpositive flag curvature is totally geodesic and there is no nondegenerate stable harmonic map from a Riemannian unit sphere Sn (n > 2) to any Finsler manifold.
ISLAND ENTREPRENEURS: INSIGHTS FROM EXCEPTIONALLY SUCCESSFUL KNOWLEDGE-DRIVEN SMES FROM 5 EUROPEAN ISLAND TERRITORIES
Authors: BALDACCHINO GODFREY
Published: October 2005

Developing successful, indigenously-owned, small scale, export-oriented, manufacturing firms from small island locations is difficult but not impossible. This paper describes key outcomes of a research project which is reviewing a selection of such successful firms from 5 European island territories. Operating in the information and communication technology sector allows small island firms to compete successfully in export markets. They often do so by depending on the wide, 'extra-island' contacts and experiences of their 'global-local' entrepreneurial founder-owners, who often leverage start-up funds from private and personal sources. The absence of notable local market opportunities induces island entrepreneurs to 'export or perish', obliging a competitive strategy from inception.
Urocortin 2 acts centrally to delay gastric emptying through sympathetic pathways while CRF and urocortin 1 inhibitory actions are vagal dependent in rats
Authors: Czimmer József , Million Mulugeta , Taché Yvette
Published: October 2005

We characterized the influence of the selective corticotropin-releasing factor 2 (CRF2) receptor agonist human urocortin 2 (Ucn 2), injected intracisternally, on gastric emptying and its mechanism of action compared with intracisternal CRF or urocortin (Ucn 1) in conscious rats. The methylcellulose phenol red solution was gavaged 20 min after peptide injection, and gastric emptying was measured 20 min later. The intracisternal injection of Ucn 2 (0.1 and 1 μg) and Ucn 1 (1 μg) decreased gastric emptying to 37.8 ± 6.9%, 23.1 ± 8.6%, and 21.6 ± 5.9%, respectively, compared with 58.4 ± 3.8% after intracisternal vehicle. At lower doses, Ucn 2 (0.03 μg) and Ucn 1 (0.1 μg) had no effect. The CRF2 antagonist astressin2-B (3 μg ic) antagonized intracisternal Ucn 2 (0.1 μg) and CRF (0.3 μg)-induced inhibition of gastric emptying. Vagotomy enhanced intracisternal Ucn 2 (0.1 or 1 μg)-induced inhibition of gastric emptying compared with sham-operated group, whereas it blocked intracisternal CRF (1 μg) inhibitory action (45.5 ± 8.4% vs. 9.7 ± 9.7%). Sympathetic blockade by bretylium prevented intracisternal and intracerebroventricular Ucn 2-induced delayed gastric emptying, whereas it did not influence intravenous Ucn 2-, intracisternal CRF-, and intracisternal Ucn 1-induced inhibition of gastric emptying. Prazosin abolished the intracisternal Ucn 2 inhibitory effect, whereas yohimbine and propranolol did not. None of the pretreatments modified basal gastric emptying. These data indicate that intracisternal Ucn 2 induced a central CRF2-mediated inhibition of gastric emptying involving sympathetic α1-adrenergic mechanisms independent from the vagus contrasting with the vagal-dependent inhibitory actions of CRF and Ucn 1.
Time-Course of Vibratory Adaptation and Recovery in Cutaneous Mechanoreceptive Afferents
Authors: Leung Y. Y. , Bensmaïa S. J. , Hsiao S. S. , Johnson K. O.
Published: October 2005

Extended suprathreshold vibratory stimulation applied to the skin results in a desensitization of cutaneous mechanoreceptive afferents. In a companion paper, we describe the dependence of the threshold shift on the parameters of the adapting stimulus and discuss neural mechanisms underlying afferent adaptation. Here we describe the time-course of afferent adaptation and recovery. We found that absolute and entrainment thresholds rise and fall exponentially during adaptation and recovery with time constants that vary with fiber type. slowly adapting type I (SA1) afferents adapt most rapidly, and pacinian (PC) afferents adapt most slowly, whereas rapidly adapting (RA) afferents exhibit intermediate rates of adaptation; SA1 fibers also recover more rapidly from adaptation than RA and PC fibers. We also showed that threshold adaptation is accompanied by a shift in the timing of the spikes within individual cycles of the adapting stimulus (i.e., a shift in the impulse phase). We invoked an integrate-and-fire model to explore possible mechanisms underlying afferent adaptation. Finally, we found that the time-course of afferent adaptation is more rapid than that of its psychophysical counterpart, as is the time-course of recovery from adaptation, suggesting that central factors play a role in the psychophysical phenomenon.
Cancer Metastasis–Suppressing Peptide Metastin Upregulates Excitatory Synaptic Transmission in Hippocampal Dentate Granule Cells
Authors: Arai Amy C. , Xia Yan-Fang , Suzuki Erika , Kessler Markus , Civelli Olivier , Nothacker Hans-Peter
Published: October 2005

Metastin is an antimetastatic peptide encoded by the KiSS-1 gene in cancer cells. Recent studies found that metastin is a ligand for the orphan G-protein–coupled receptor GPR54, which is highly expressed in specific brain regions such as the hypothalamus and parts of the hippocampus. This study shows that activation of GPR54 by submicromolar concentrations of metastin reversibly enhances excitatory synaptic transmission in hippocampal dentate granule cells in a mitogen-activated protein (MAP) kinase–dependent manner. Synaptic enhancement by metastin was suppressed by intracellular application of the G-protein inhibitor GDP-β-S and the calcium chelator BAPTA. Analysis of miniature excitatory postsynaptic currents (mEPSCs) revealed an increase in the mean amplitude but no change in event frequency. This indicates that GPR54 and the mechanism responsible for the increase in EPSCs are postsynaptic. Metastin-induced synaptic potentiation was abolished by 50 μM PD98059 and 20 μM U0126, two inhibitors of the MAP kinases ERK1 and ERK2. The effect was also blocked by inhibitors of calcium/calmodulin-dependent kinases and tyrosine kinases. RT-PCR experiments showed that both KiSS-1 and GPR54 are expressed in the hippocampal dentate gyrus. Metastin is thus a novel endogenous factor that modulates synaptic excitability in the dentate gyrus through mechanisms involving MAP kinases, which in turn may be controlled upstream by calcium-activated kinases and tyrosine kinases.
Orientation-Selective Adaptation to First- and Second-Order Patterns in Human Visual Cortex
Authors: Larsson Jonas , Landy Michael S. , Heeger David J.
Published: October 2005

Second-order textures—patterns that cannot be detected by mechanisms sensitive only to luminance changes—are ubiquitous in visual scenes, but the neuronal mechanisms mediating perception of such stimuli are not well understood. We used an adaptation protocol to measure neural activity in the human brain selective for the orientation of second-order textures. Functional MRI (fMRI) responses were measured in three subjects to presentations of first- and second-order probe gratings after adapting to a high-contrast first- or second-order grating that was either parallel or orthogonal to the probe gratings. First-order (LM) stimuli were generated by modulating the stimulus luminance. Second-order stimuli were generated by modulating the contrast (CM) or orientation (OM) of a first-order carrier. We used four combinations of adapter and probe stimuli: LM:LM, CM:CM, OM:OM, and LM:OM. The fourth condition tested for cross-modal adaptation with first-order adapter and second-order probe stimuli. Attention was diverted from the stimulus by a demanding task at fixation. Both first- and second-order stimuli elicited orientation-selective adaptation in multiple cortical visual areas, including V1, V2, V3, V3A/B, a newly identified visual area anterior to dorsal V3 that we have termed LO1, hV4, and VO1. For first-order stimuli (condition LM:LM), the adaptation was no larger in extrastriate areas than in V1, implying that the orientation-selective first-order (luminance) adaptation originated in V1. For second-order stimuli (conditions CM:CM and OM:OM), the magnitude of adaptation, relative to the absolute response magnitude, was significantly larger in VO1 (and for condition CM:CM, also in V3A/B and LO1) than in V1, suggesting that second-order stimulus orientation was extracted by additional processing after V1. There was little difference in the amplitude of adaptation between the second-order conditions. No consistent effect of adaptation was found in the cross-modal condition LM:OM, in agreement with psychophysical evidence for weak interactions between first- and second-order stimuli and computational models of separate mechanisms for first- and second-order visual processing.
Representation of Eye Position in Primate Inferior Colliculus
Authors: Porter Kristin Kelly , Metzger Ryan R. , Groh Jennifer M.
Published: October 2005

We studied the representation of eye-position information in the primate inferior colliculus (IC). Monkeys fixated visual stimuli at one of eight or nine locations along the horizontal meridian between −24 and 24° while sounds were presented from loudspeakers at locations within that same range. Approximately 40% of our sample of 153 neurons showed statistically significant sensitivity to eye position during either the presentation of an auditory stimulus or in the absence of sound (Bonferroni corrected P < 0.05). The representation for eye position was predominantly monotonic and favored contralateral eye positions. Eye-position sensitivity was more prevalent among neurons without sound-location sensitivity: about half of neurons that were insensitive to sound location were sensitive to eye position, whereas only about one-quarter of sound-location-sensitive neurons were also sensitive to eye position. Our findings suggest that sound location and eye position are encoded using independent but overlapping rate codes at the level of the IC. The use of a common format has computational advantages for integrating these two signals. The differential distribution of eye-position sensitivity and sound-location sensitivity suggests that this process has begun by the level of the IC but is not yet complete at this stage. We discuss how these signals might fit into Groh and Sparks' vector subtraction model for coordinate transformations.
Attenuation of Sensory and Affective Responses to Heat Pain: Evidence for Contralateral Mechanisms
Authors: Gallez Ariane , Albanese Marie-Claire , Rainville Pierre , Duncan Gary H.
Published: October 2005

Attenuation of responses to repeated sensory events has been thoroughly studied in many modalities; however, attenuation of pain perception has not yet benefitted from such extensive investigation. Described here are two psychophysical studies that examined the effects of repeated exposure to thermal stimuli, assessing potential attenuation of the perception of pain and its possible spatial specificity. Twenty-two subjects were presented thermal stimuli to the volar surface of the right and left forearms. Twelve subjects in study 1 received the same stimuli and conditions on each of five daily experimental sessions, whereas 10 subjects in study 2 received thermal stimuli, which were restricted to one side for four daily sessions and then applied to the other side on the fifth session. Ratings of warmth intensity, pain intensity, and pain unpleasantness were recorded while the subjects performed a thermal sensory discrimination task. Results of study 1 demonstrate that repeated stimulation with noxious heat can lead to long-term attenuation of pain perception; results of study 2 extend these findings of attenuation to both pain intensity and unpleasantness and show that this effect is highly specific to the exposed body side for both aspects of the pain experience. We suggest that the functional plasticity underlying this attenuation effect lies in brain areas with a strong contralateral pattern of pain-related activation.
Measurement of Tracheal Humidity and Temperature
Authors: Liener Kristina , Dürr Jochen , Leiacker Richard , Rozsasi Ajnacska , Keck Tilman
Published: October 2005

Background: After tracheostomy, patients often present with chest complaints. Measurement of objective parameters of the tracheal climate is important to evaluate ‘artificial noses’ or humidifying devices. Objectives: The purpose of this study was to present an experimental setup for measurement of tracheal temperature and humidity for possible use in clinical studies in tracheotomized patients. Methods: The study design was a prospective study. Patients with tracheal stoma were chosen as study participants. Tracheal temperature and humidity during the respiratory cycle were measured using a miniaturized thermocouple and a humidity sensor connected to a suction system. Results: Accurate measurement of tracheal temperature and humidity was feasible in patients with tracheal stoma. Tracheal humidity and temperature values measured in this study were similar to values reported earlier by other working groups. Conclusions: The experimental setup presented may reliably be used in the evaluation of ‘artificial noses’ or other passive humidifiers in tracheotomized patients.
Respiratory Failure Secondary to Organizing Pneumonia in a Patient with Membranoproliferative Glomerulonephritis and Lung Haemorrhage
Authors: Sánchez Rosario , Gil Joan , Barroso Encarnación , Rivera Francisco , Aranda Ignacio , Romero Santiago
Published: October 2005

We report the case of a woman with membranoproliferative glomerulonephritis type I who presented with acute respiratory failure secondary to alveolar haemorrhage. The persistence of the respiratory failure, once the alveolar haemorrhage had ceased, was apparently due to diffuse alveolar damage in organization. The recognition of this proliferative reaction through the performance of transbronchial biopsy allowed the initiation of a correct treatment with which a favourable response was obtained.
Health-Related Quality of Life in Community-Dwelling Men with Pneumoconiosis
Authors: Tang Wai Kwong , Lum C.M. , Ungvari Gabor S. , Chiu Helen F.K.
Published: October 2005

Background: There have been few data on the health-related quality of life (HRQOL) in patients with pneumoconiosis. HRQOL is an important aspect of daily living in patients with industrial diseases. Objectives: To investigate the HRQOL and factors that contribute to the impairment of HRQOL in patients with pneumoconiosis. Methods: 297 patients with pneumoconiosis were recruited from a community-based case registry. The HRQOL was measured with the St. George’s Respiratory Questionnaire (SGRQ). Pulmonary function, comorbidity and psychosocial variables were also assessed. Patients’ mood state was evaluated with the Geriatric Depression Scale (GDS). Results: The mean SGRQ symptom, activity, impact and total scores were 38.0 ± 19.3, 44.5 ± 21.9, 34.2 ± 17.9 and 39.4 ± 17.4, respectively. These figures were lower than those reported in patients with chronic obstructive pulmonary disease who attended chest clinics. The GDS score (r = 0.38), forced expiratory volume in 1 s predicted (FEV1% predicted;r = –0.33) and comorbidity (r = 0.21) were the most important predictors of the HRQOL. Conclusions: Besides lung functions, chest clinicians should consider the impact of mood symptoms and comorbidity on the HRQOL in the management of patients with pneumoconiosis.
Disseminated Mycobacterium avium Infection in a 20-Year-Old Female with Partial Recessive IFNγR1 Deficiency
Authors: Remiszewski Paweł , Roszkowska-Śliz Barbara , Winek Jolanta , Chapgier Ariane , Feinberg Jacquelin , Langfort Renata , Bestry Iwona , Augustynowicz-Kopeć Ewa , Ptak Jakub , Casanova Jean-Laurent , Rowińska-Zakrzewska Ewa
Published: October 2005

We report the case of a 20-year-old female with disseminated Mycobacterium avium disease involving bones, lungs and brain. She was completely healthy up until the present illness and had been vaccinated with BCG in infancy without complications. Mycobacteriosis progressed in spite of treatment with antituberculous drugs and was controlled only after addition of interferon-γ subcutaneously. A homozygous hypomorphic I87T mutation was found in the gene encoding the ligand-binding chain of the IFN-γ receptor (IFNγR1). This mutation is the only known recessive hypomorphic lesion in IFNGR1 and had been reported before in only 1 child with curable BCG infection and his sibling with primary tuberculosis. Our report illustrates the clinical heterogeneity of patients sharing exactly the same form of partial recessive IFNγR1 deficiency. A diagnosis of partial recessive IFNγR1 deficiency should be contemplated in adults with unexplained environmental mycobacterial diseases.
Overexpression of Bcl-2 Protein in Bronchoalveolar Lavage Lymphocytes and Macrophages in Sarcoidosis
Authors: Mermigkis C. , Polychronopoulos V. , Mermigkis D. , Tsakanika K. , Heretis M. , Karagianidis N. , Bouros D.
Published: October 2005

Background and Objectives: Apoptosis, also known as programmed cell death, probably correlates with the pathophysiologic mechanisms of alveolitis in sarcoidosis. Our purpose was to investigate any changes in the expression of the antiapoptotic protein Bcl-2, one of the most important inhibiting factors of apoptosis, in bronchoalveolar lavage fluid (BALF) cell populations in patients with sarcoidosis. Subjects and Methods: Fiberoptic bronchoscopy with BAL was performed in 13 patients with active sarcoidosis (10 patients with stage I and 3 with stage II disease based on chest radiography). None of them was under treatment with corticosteroids. Cellular Bcl-2 expression was identified using an immunoperoxidase staining method. Ten normal subjects served as control group. Results: BALF lymphocytes and macrophages in sarcoid patients exhibited a significant increase in the expression of Bcl-2 compared with the control group (p < 0.001). A Bcl-2 expression of 80.7 ± 8.5% in the lymphocytes and 77.4 ± 8.9% in the macrophages was observed in sarcoidosis versus 32.2 ± 13.8% and 19.6% ± 7.6% in normal subjects, respectively. The percentages of Bcl-2 expression in the lymphocytes were positively correlated with BALF CD4/CD8 ratio values (p = 0.02, r = 0.63). Conclusions: Our results suggest that the antiapoptotic protein Bcl-2 is overexpressed in alveolar lymphocytes and macrophages, which characterize the alveolitis in sarcoidosis and could provide insights into the pathogenesis of the disease and prove useful as a marker of disease activity or response to therapy.
Serum Adiponectin Levels in Adult Male Patients with Obstructive Sleep Apnea Hypopnea Syndrome
Authors: Zhang Xi-Long , Yin Kai-Sheng , Wang Hong , Su Shicheng
Published: October 2005

Background: Adiponectin has been found to be associated with the pathogenesis of diabetes, obesity and some cardiovascular diseases, which usually coexist with obstructive sleep apnea hypopnea syndrome (OSAHS). However, an association between adiponectin and OSAHS has rarely been reported. Objectives: To investigate the levels of serum adiponectin in adult male patients with OSAHS. Methods: Following polysomnographic examination, 86 adult male habitual snorers were divided into simple snorers (control group) and OSAHS patients (OSAHS group) who were further divided into mild, moderateandsevere OSAHS subgroups based on their apnea hypopnea index (AHI). There was no significant difference in age, body mass index (BMI), fasting blood glucose (FBG) and insulin resistance expressed as homeostasis model assessment (HOMA) between the two groups. The serum adiponectin levels were measured by radioimmunoassay. Results: Serum adiponectin levels were significantly lower in the OSAHS group than in the control (p< 0.01). Such a decrease in adiponectin level was most significant in patients with moderate and severe OSAHS. Pearson correlation analysis showed that in OSAHS patients, serum adiponectin level was negatively correlated with BMI, waist (WC) and neck (NC) circumferences, AHI and HOMA, but positively correlated with nadir pulse oxyhemoglobin saturation (nadir SpO2). After controlling for HOMA, BMI, NC and WC in OSAHS patients, a partial correlation analysis showed that adiponectin levels were negatively correlated with AHI but positively correlated with nadir SpO2. Multiple logistic regression analysis indicated that adiponectin was independently associated with OSAHS. Conclusions: Serum adiponectin levels were significantly lower in OSAHS patients than in simple snorers. OSAHS may cause a decrease in serum adiponectin level.
An Unusual Iatrogenic Foreign Body (Surgical Gauze) in the Trachea
Authors: Tabuena Rollin P. , Zuccatosta Lina , Tubaldi Alberto , Gasparini Stefano
Published: October 2005

We report the case of a 60-year-old male with history of surgery for tracheal stenosis 21 years prior to the onset of difficult asthma-like symptoms. Upon exploring the tracheobronchial tree using the fiberoptic bronchoscope, a surgical gauze was found. The foreign body migrated transluminally from the mediastinum into the trachea and its removal was possible with rigid bronchoscopy leading to a rapid recovery of his symptoms.
Alveolar Volume Determined by Single-Breath Helium Dilution Correlates with the High-Resolution Computed Tomography-Derived Nonemphysematous Lung Volume
Authors: van der Lee I. , van Es H.W. , Noordmans H.J. , van den Bosch J.M.M. , Zanen P.
Published: October 2005

Background: The alveolar volume (VA), determined by single-breath helium dilution, is a measure for the total lung capacity (TLC) that is very sensitive to ventilatory disturbances. In chronic obstructive pulmonary disease (COPD), the emphysematous lung parts are less accessible to test gas; therefore, the VA is smaller than TLC measured by multiple-breath helium dilution (TLCHe). Objectives: The aim of this study was to investigate whether the VA represents the nonemphysematous lung parts. Methods: We measured VA as part of the diffusing capacity for carbon monoxide (DLCO), TLCHe and spirometry in 50 patients with COPD. High-resolution computed tomography (HRCT) scans of all subjects were analyzed with the density mask method, where parts with an attenuation of less than –950 Hounsfield units were considered as emphysematous. Results: A strong correlation was observed between the VA (mean 5.2 liters) and nonemphysematous HRCT lung volume (mean 5.2 liters, r2 = 0.9) and between the TLCHe (mean 6.6 liters) and total HRCT lung volume (mean 6.4 liters, r2 = 0.9). Bland-Altman plots showed considerable disagreement between the VA and the nonemphysematous HRCT lung volume. A weak correlation between the forced expiratory volume in 1 s (mean 46% predicted) and DLCO (mean 46% predicted) versus the HRCT emphysema ratio (nonemphysematous/total HRCT lung volume) was observed (r2 = 0.3 and 0.3, respectively). Conclusion: We concluded that the VA correlates with the nonemphysematous HRCT lung volume, although the two measurements are not equivalent, possibly due to technical factors.
Bronchoscopic Surfactant Administration in Pediatric Patients with Persistent Lobar Atelectasis
Authors: Krause Martin F. , von Bismarck Philipp , Oppermann Hans C. , Ankermann Tobias
Published: October 2005

Persistent lobar atelectasis in pediatric patients on mechanical ventilation results in impaired gas exchange and lung mechanics and contributes to a further need for mechanical ventilation. The most common types of atelectasis in children are resorption atelectasis following airway obstruction, and atelectasis due to surfactant deficiency or dysfunction. We aimed to determine whether bronchoscopic suctioning and surfactant application to atelectatic lung segments would result in improved oxygenation, ventilation, chest X-ray scoring, and early extubation. Five children with heterogeneous lung diseases (aged between 7 months and 15 years) were treated with a diluted surfactant preparation (CurosurfTM) in a concentration of 5–10 mg/ml (total dose 120–240 mg) which was instilled into the affected segments. Outcome parameters were gas exchange, radiographic resolution of atelectasis and extubation. All mechanically ventilated patients could be extubated within 24 h following the intervention. Bronchoscopic surfactant application could be carried out without adverse effects and brought improvements in oxygenation, respiratory rate, and partial or complete resolution of atelectases without recurrence.
Heart Valve Tissue Engineering
Authors: Vesely Ivan
Published: October 2005

Tissue-engineered heart valves have been proposed by physicians and scientists alike to be the ultimate solution for treating valvular heart disease. Rather than replacing a diseased or defective native valve with a mechanical or animal tissue–derived artificial valve, a tissue-engineered valve would be a living organ, able to respond to growth and physiological forces in the same way that the native aortic valve does. Two main approaches have been attempted over the past 10 to 15 years: regeneration and repopulation. Regeneration involves the implantation of a resorbable matrix that is expected to remodel in vivo and yield a functional valve composed of the cells and connective tissue proteins of the patient. Repopulation involves implanting a whole porcine aortic valve that has been previously cleaned of all pig cells, leaving an intact, mechanically sound connective tissue matrix. The cells of the patients are expected to repopulate and revitalize the acellular matrix, creating living tissue that already has the complex microstructure necessary for proper function and durability. Regrettably, neither of the 2 approaches has fared well in animal experiments, and the only clinical experience with tissue-engineered valves resulted in a number of early failures and patient death. This article reviews the technological details of the 2 main approaches, their rationale, their strengths and weaknesses, and the likely mechanisms for their failure. Alternative approaches to valvular tissue engineering, as well as the role of industry in shaping this field in the future, are also reviewed.
Reading Derrida's New Testament: A Critical Appraisal
Authors: Twomey Jay
Published: October 2005

Derrida is a source of profound inspiration for many scholars in recent New Testament studies. He makes available a variety of critical tools with which to examine the fissures and rough edges of the New Testament texts, not (as with source and form critics) in order to reconstitute their origins and original meanings, but rather in recognition of the indeterminacies which constitute the texts themselves. Given his growing importance to the field, however, it is surprising to note that Derrida's own readings of the New Testament often fail to exemplify even the most basic possibilities that deconstruction has to offer. In his hands, the New Testament can take on a surprising resistance to deconstructive critique. This essay is primarily an effort at encouraging New Testament scholars (who clearly can out-Derrida Derrida with regard to the New Testament) to return to Derrida's readings of certain New Testament texts with a fresh, critical eye. It examines a number of Derrida's New Testament interventions, and in the process shows (a) the ways in which his reading of the texts is at odds with the critical project within which it is embedded, and (b) what a more adequately deconstructive reading of the same texts might look like. The article concludes with a complex of tentative thoughts on why Derrida's readings of the New Testament can seem so inadequately Derridean.
Lady Boards of Managers: Subjugated Legacies of Governance and Administration
Authors: Netting F. Ellen , O’Connor Mary Katherine
Published: October 2005

Three traditions of women’s organizations emerged in the 1800s: benevolence, reform, and rights. This article focuses primarily on women who founded the forerunners of today’s nonprofit health and human service agencies. Using Richmond, Virginia, as an example, it draws from historical documents, as well as the literature, to reframe the importance of what Lady Boards of Managers did in shaping the governance and administration of early human service organizations. Of particular importance is the invisibility of their actions, which were extraordinary for the times in which they lived, in the theories and practice models that drive current macro-social work practice.
The Era of Meanness: Welfare Reform and Barriers to a College Degree
Authors: Weikart Lynne A.
Published: October 2005

In response to the passage of the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 and the accompanying block grant, Temporary Assistance for Needy Families, broad-based advocacy coalitions formed in many states to lobby for meaningful college programs for welfare recipients. State by state, these coalitions wrestled with creating programs that would allow welfare recipients to remain in 4-year colleges, but only a few states managed to develop such programs. This article compares the advocacy coalitions in two states, Maine and New York, where welfare advocates struggled to achieve progressive state welfare higher educational policies and, in some instances, succeeded in keeping welfare recipients in 4-year colleges.
Trained Volunteers as Mental Health Counselors: Addressing the Enormous Shortage of Trained Counselors
Authors: Wilson Ann M.
Published: October 2005

The spirit of service and volunteering in nonprofit and community-based organizations has been a staple of American life for hundreds of years. Although courts have referred clients to mental health agencies since the end of the 19th century, volunteers who are trained mental health counselors are a phenomenon that agencies have only recently used to address both court-ordered and other referrals. This article highlights one successful countywide model that can be replicated nationwide and can be a powerful tool in any community.
A Narrative Principle for Feminist Social Work With Survivors of Male Violence
Authors: Roche Susan E. , Wood Gale Goldberg
Published: October 2005

Blame surrounds and embeds male violence against women, acting as oppressive propaganda that shapes survivors’ identities, which, in turn, reduce their options. This article challenges the notion that violence against women renders women passive and precludes their resistance. It describes a narrative practice principle—coconstructing women’s new identity stories—to guide social work in countering this propaganda with women survivors of male violence. Blame is addressed as a cultural narrative within which some women are targeted by male violence and all women construct their identities. As a feminist social work principle, coconstructing women’s new identity stories connects the political and the individual facets of male violence, expanding women’s options for action. Specifically, the article presents the principle and three processes for translating it into action.
Gender differences in respiratory symptoms in 19-year-old adults born preterm
Authors: Vrijlandt Elianne JLE , Gerritsen Jorrit , Boezen H Marike , Duiverman Eric J ,   the Dutch POPS-19 Collaborative Study Group*
Published: October 2005

Objective

To study the prevalence of respiratory and atopic symptoms in (young) adults born prematurely, differences between those who did and did not develop Bronchopulmonary Disease (BPD) at neonatal age and differences in respiratory health between males and females.

Methods

Design: Prospective cohort study.

Setting:Nation wide follow-up study, the Netherlands.

Participants:690 adults (19 year old) born with a gestational age below 32 completed weeks and/or with a birth weight less than 1500 g. Controls were Dutch participants of the European Community Respiratory Health Survey (ECRHS).

Main outcome measures:Presence of wheeze, shortness of breath, asthma, hay fever and eczema using the ECRHS-questionnaire

Results

The prevalence of doctor-diagnosed asthma was significantly higher in the ex-preterms than in the general population, whereas eczema and hay fever were significant lower. Women reported more symptoms than men. Preterm women vs controls: asthma 13% vs 5% (p < 0.001); hay fever 8% vs 20% (p < 0.001); eczema 10% vs 42% (p < 0.001). Preterm men vs controls: asthma 9% vs 4% (p = 0.007); hay fever 8% vs 17% (p = 0.005); eczema 9% vs 31% (p < 0.001) Preterm women reported more wheeze and shortness of breath during exercise (sob) than controls: wheeze 30% vs 22% (p = 0.009); sob 27% vs 16% (p < 0.001); 19-year-old women with BPD reported a higher prevalence of doctor diagnosed asthma compared to controls (24% vs 5% p < 0.001) and shortness of breath during exercise (43% vs 16% p = 0.008). The prevalence of reported symptoms by men with BPD were comparable with the controls.

Conclusion

Our large follow-up study shows a higher prevalence of asthma, wheeze and shortness of breath in the prematurely born young adults. 19-year-old women reported more respiratory symptoms than men. Compared to the general population atopic diseases as hay fever and eczema were reported less often.
Nonnatural amino acid incorporation into the methionine 214 position of the metzincin Pseudomonas aeruginosa alkaline protease
Authors: Walasek Paula , Honek John F
Published: October 2005

Background

The alkaline protease fromPseudomonas aeruginosa(AprA) is a member of the metzincin superfamily of metalloendoproteases. A key feature of these proteases is a conserved methionine-containing 1,4-tight β turn at the base of the active site zinc binding region.

Results

To explore the invariant methionine position in this class of protease, incorporation of a nonnatural fluorinated methionine, L-difluoromethionine (DFM), into this site was accomplished. Although overproduction of the N-terminal catalytic fragment of AprA resulted in protein aggregates which could not be resolved, successful heterologous production of the entire AprA was accomplished in the presence and absence of the nonnatural amino acid. DFM incorporation was found to only slightly alter the enzyme kinetics of AprA. In addition, differential scanning calorimetry indicated no significant alteration in the thermal stability of the modified enzyme.

Conclusion

Although invariant in all metzincin proteases, the methionine 214 position in AprA can be successfully replaced by the nonnatural amino acid DFM resulting in little effect on protein structure and function. This study indicates that the increased size of the methyl group by the introduction of two fluorines is still sufficiently non-sterically demanding, and bodes well for the application of DFM to biophysical studies of protein structure and function in this class of protease.
MASQOT: a method for cDNA microarray spot quality control
Authors: Bylesjö Max , Eriksson Daniel , Sjödin Andreas , Sjöström Michael , Jansson Stefan , Antti Henrik , Trygg Johan
Published: October 2005

Background

cDNA microarray technology has emerged as a major player in the parallel detection of biomolecules, but still suffers from fundamental technical problems. Identifying and removing unreliable data is crucial to prevent the risk of receiving illusive analysis results. Visual assessment of spot quality is still a common procedure, despite the time-consuming work of manually inspecting spots in the range of hundreds of thousands or more.

Results

A novel methodology for cDNA microarray spot quality control is outlined. Multivariate discriminant analysis was used to assess spot quality based on existing and novel descriptors. The presented methodology displays high reproducibility and was found superior in identifying unreliable data compared to other evaluated methodologies.

Conclusion

The proposed methodology for cDNA microarray spot quality control generates non-discrete values of spot quality which can be utilized as weights in subsequent analysis procedures as well as to discard spots of undesired quality using the suggested threshold values. The MASQOT approach provides a consistent assessment of spot quality and can be considered an alternative to the labor-intensive manual quality assessment process.
Polyamine stress at high pH in Escherichia coli K-12
Authors: Yohannes Elizabeth , Thurber Amy E , Wilks Jessica C , Tate Daniel P , Slonczewski Joan L
Published: October 2005

Background

Polyamines such as spermine and spermidine are required for growth of Escherichia coli; they interact with nucleic acids, and they bind to ribosomes. Polyamines block porins and decrease membrane permeability, activities that may protect cells in acid. At high concentrations, however, polyamines impair growth. They impair growth more severely at high pH, probably due to their increased uptake as membrane-permeant weak bases. The role of pH is critical in understanding polyamine stress.

Results

The effect of polyamines was tested on survival of Escherichia coli K-12 W3110 in extreme acid or base (pH conditions outside the growth range). At pH 2, 10 mM spermine increased survival by 2-fold, and putrescine increased survival by 30%. At pH 9.8, however, E. coli survival was decreased 100-fold by 10 mM spermine, putrescine, cadaverine, or spermidine. At pH 8.5, spermine decreased the growth rate substantially, whereas little effect was seen at pH 5.5. Spermidine required ten-fold higher concentrations to impair growth. On proteomic 2-D gels, spermine and spermidine caused differential expression of 31 different proteins. During log-phase growth at pH 7.0, 1 mM spermine induced eight proteins, including PykF, GlpK, SerS, DeaD, OmpC and OmpF. Proteins repressed included acetate-inducible enzymes (YfiD, Pta, Lpd) as well as RapA (HepA), and FabB. At pH 8.5, spermine induced additional proteins: TnaA, OmpA, YrdA and NanA (YhcJ) and also repressed 17 proteins. Four of the proteins that spermine induced (GlpK, OmpA, OmpF, TnaA) and five that were repressed (Lpd, Pta, SucB, TpiA, YfiD) show similar induction or repression, respectively, in base compared to acid. Most of these base stress proteins were also regulated by spermidine, but only at ten-fold higher concentration (10 mM) at high pH (pH 8.5).

Conclusion

Polyamines increase survival in extreme acid, but decrease E. coli survival in extreme base. Growth inhibition by spermine and spermidine requires neutral or higher pH. At or above pH 7, spermine and spermidine regulate specific proteins, many of which are known to be regulated by base stress. High pH amplifies polyamine stress; and naturally occurring polyamines may play an important role in base stress.
Genometrics as an essential tool for the assembly of whole genome sequences: the example of the chromosome of Bifidobacterium longum NCC2705
Authors: Guy Lionel , Karamata Dimitri , Moreillon Philippe , Roten Claude-Alain H
Published: October 2005

Background

Analysis of the first reported complete genome sequence ofBifidobacterium longumNCC2705, an actinobacterium colonizing the gastrointestinal tract, uncovered its proteomic relatedness toStreptomyces coelicolorandMycobacterium tuberculosis. However, a rapid scrutiny by genometric methods revealed a genome organization totally different from all so far sequenced high-GC Gram-positive chromosomes.

Results

Generally, the cumulative GC- and ORF orientation skew curves of prokaryotic genomes consist of two linear segments of opposite slope: the minimum and the maximum of the curves correspond to the origin and the terminus of chromosome replication, respectively. However, analyses of theB. longumNCC2705 chromosome yielded six, instead of two, linear segments, while itsdnaAlocus, usually associated with the origin of replication, was not located at the minimum of the curves. Furthermore, the coorientation of gene transcription with replication was very low.

Comparison with closely related actinobacteria strongly suggested that the chromosome ofB. longumwas misassembled, and the identification of two pairs of relatively long homologous DNA sequences offers the possibility for an alternative genome assembly proposed here below. By genometric criteria, this configuration displays all of the characters common to bacteria, in particular to related high-GC Gram-positives. In addition, it is compatible with the partially sequenced genome of DJO10AB. longumstrain. Recently, a corrected sequence ofB. longumNCC2705, with a configuration similar to the one proposed here below, has been deposited in GenBank, confirming our predictions.

Conclusion

Genometric analyses, in conjunction with standard bioinformatic tools and knowledge of bacterial chromosome architecture, represent fast and straightforward methods for the evaluation of chromosome assembly.