bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dimensional vs. categorical diagnosis in psychosis
Authors: Rosenman S. , Korten A. , Medway J. , Evans M. 
Published: May 2003

Objective:  To compare dimensional measures vs. categorical diagnosis of psychopathology in their prediction of disability and outcome in psychotic illness.Method:  A community study of 980 subjects with psychotic illness was included in the Australian National Survey of Mental Health and Wellbeing. The study instrument [including the Schedules for Clinical Assessment in Neuropsychiatry (SCAN)] yielded symptom data along with Operational Criteria for Psychotic Illness (OPCRIT) diagnoses by several diagnostic schemata. Factor analysis of symptoms yielded five dimensions of psychopathology (positive symptoms, negative symptoms, dysphoria, mania and substance use). Variance in service demand and disability explained by the diagnostic schemata was compared with the variance explained by the dimensions of psychopathology.Results:  Dimensional measures of psychopathology explained more of the variance in service demand, dysfunctional behaviour, social adaptation and global occupation and function. Only use of support services and illness course were better predicted by categorical diagnosis. Dimensional scores explained significant extra variance when added to categorical diagnoses.Conclusion:  Dimensional measures of psychopathology explain more variance in behaviour, disability and outcome than does categorical diagnosis in functional psychosis. Dimensions provided significant extra information not provided by diagnosis and would be a more useful basis for clinical management.
The relationship between insulin, IGF‐I and weight gain in cystic fibrosis
Authors: Taylor A. M. , Thomson A. , Bruce‐Morgan C. , Ahmed M. L. , Watts A. , Harris D. , Holly J. M. P. , Dunger D. B. 
Published: May 2003

OBJECTIVEIn cystic fibrosis, reduced body mass is related to low levels of IGF‐I and changes in the IGF binding proteins. Our aim was to determine whether these abnormalities are linked to pancreatic endocrine dysfunction.PATIENTS AND DESIGNWe measured serum levels of insulin, IGF‐I, IGFBP‐I, IGFBP‐3 and IGF bioactivity in 77 fasting subjects (43 male) mean age 9.6 years (range 2.99–17.98 years). Data were analysed with respect of body mass, puberty and stature and compared with control data established in the same laboratory.RESULTSThe mean height standard deviation score (SDS (SD)) was −0.54 (0.97) and the body mass index SDS −0.24 (1.09). Both body mass index SDS (r = −0.40, P = 0.0003) and IGF‐I SDS (r = − 0.32, P = 0.009) declined with age. Insulin levels were also low and correlated with IGF‐I and IGFBP‐3 (r = 0.42, P = 0.0004, and r = 0.45, P = 0.0002, respectively) whereas levels of IGFBP‐I were inversely related to those of IGF‐I and insulin (r = − 0.43, P = 0.0004, r = − 0.52, P < 0.0001). IGF bioactivity was reduced and inversely related to IGFBP‐I (r = − 0.31, P = 0.009). In multiple regression analysis, body mass index SDS was negatively related to age (P < 0.0001) and positively related to insulin and IGF‐I (P = 0.04, P = 0.03, respectively). Height SDS was correlated with IGF bioactivity (P = 0.003) and negatively with IGFBP‐I (P = 0.01).CONCLUSIONSWe conclude that progressive insulin deficiency may result in reduced IGF‐I levels and IGF‐bioactivity and may determine weight gain and statural growth in cystic fibrosis.
Relationship between ovarian cortisol:cortisone ratios and the clinical outcome of in vitro fertilization and embryo transfer (IVF‐ET)
Authors: Michael Anthony E. , Collins Tracey D. , Norgate Dean P. , Gregory Linda , Wood Peter J. , Cooke Brian A. 
Published: May 2003

OBJECTIVEPreviously, we have reported an association between low levels of intraovarian cortisol metabolism, mediated by 11β‐hydroxysteroid dehydrogenase (11βHSD), and the establishment of pregnancies by in vitro fertilization and embryo transfer (IVF‐ET). The objective of the present study was to investigate the relationship between the clinical outcome of IVF‐ET and the intraovarian concentrations of cortisol and cortisone and the cortisol:cortisone ratios in random samples of ovarian follicular fluid (FF).DESIGNRetrospective, double‐blind correlation analyses.PATIENTSFF samples (n = 41) were obtained from 23 women undergoing gonadotrophin‐stimulated IVF‐ET cycles at the Cardiff Assisted Reproduction Unit.MEASUREMENTSClinical pregnancy was confirmed by ultrasonography. Intrafollicular steroid concentrations were measured by radioimmunoassays.RESULTSConcentrations of both cortisol and cortisone were significantly lower in FF samples obtained from 6 patients that conceived than in samples obtained from 17 patients that did not achieve pregnancy (cortisol (mean ± SEM) = 304 ± 29 vs. 407 ± 26 nmol/l, P = 0.0411; cortisone = 32 ± 3 vs. 65 ± 7 nmol/l, P = 0.0002). Intrafollicular cortisol:cortisone ratios were significantly higher in samples from conception cycles than in those samples obtained from nonconception cycles (9.7 ± 0.7 vs. 6.9 ± 0.5, respectively, P = 0.0060). Whereas 5 of 10 women with intrafollicular cortisol:cortisone ratios greater than the outcome‐independent mean of 7.7 became pregnant, only 1 of the 13 patients with intrafollicular cortisol:cortisone ratios < 7.7 conceived (χ2 = 5.247, P = 0.0220).CONCLUSIONSConcentrations of both cortisol and cortisone were significantly lower in FF samples obtained from patients that conceived by IVF‐ET than in those obtained from nonconception cycles. Conception by gonadotrophin‐stimulated IVF‐ET was associated with an elevated intrafollicular ratio of cortisol:cortisone, consistent with a low level of intraovarian cortisol oxidation by 11βHSD.
Automated quantification and reconstruction of collagen matrix from 3D confocal datasets
Authors: Wu J. , Rajwa B. , Filmer D. L. , Hoffmann C. M. , Yuan B. , Chiang C. , Sturgis J. , Robinson J. P. 
Published: May 2003

SummaryThe geometrical structure of fibrous extracellular matrix (ECM) impacts on its biological function. In this report, we demonstrate a new algorithm designed to extract quantitative structural information about individual collagen fibres (orientation, length and diameter) from 3D backscattered‐light confocal images of collagen gels. The computed quantitative data allowed us to create surface‐rendered 3D images of the investigated sample.
Daytime sleepiness during Ramadan intermittent fasting: polysomnographic and quantitative waking EEG study
Authors: Roky Rachida , Chapotot Florian , Benchekroun Majda Taoudi , Benaji Brahim , Hakkou Farid , Elkhalifi Hassan , Buguet Alain 
Published: May 2003

SummaryDuring the lunar month of Ramadan, Muslims abstain from eating, drinking and smoking from sunrise to sunset. We reported previously that Ramadan provokes a shortening in nocturnal total sleep time by 40 min, an increase in sleep latency, and a decrease in slow‐wave sleep (SWS) and rapid eye movement (REM) sleep duration during Ramadan. During the same study, the effects of Ramadan intermittent fasting on daytime sleepiness were also investigated in eight healthy young male subjects using a quantitative waking electroencephalograph (EEG) analysis following the multiple sleep latency test (MSLT) procedure. This procedure was combined with subjective alertness and mood ratings and was conducted during four successive experimental sessions: (1) baseline (BL) 15 days before Ramadan, (2) beginning of Ramadan (R11) on the 11th day of Ramadan, (3) end of Ramadan (R25) on the 25th day of Ramadan, (4) recovery 2 weeks after Ramadan (AR). During each session, four 20‐min nap opportunities (MSLTs) were given at 10:00, 12:00, 14:00 and 16:00 h and were preceded by rectal temperature readings. Nocturnal sleep was recorded before each daytime session. Subjective daytime alertness did not change in R25 but decreased in R11 at 12:00 h, and subjective mood decreased at 16:00 h, both in R11 and R25. During the MSLT, mean sleep latency decreased by an average of 2 min in R11 (especially at 10:00 and 16:00 h) and 6 min in R25 (especially at 10:00 and 12:00 h) compared with BL. There was an increase in the daily mean of waking EEG absolute power in the theta (5.5–8.5 Hz) frequency band. Significant correlations were found between sleep latency during the MSLT and the waking EEG absolute power of the fast alpha (10.5–12.5 Hz), sigma (11.5–15.5 Hz) and beta (12.5–30 Hz) frequency bands. Sleep latency was also related to rectal temperature. In conclusion, Ramadan diurnal fasting induced an increase in subjective and objective daytime sleepiness associated with changes in diurnal rectal temperature.
Practicality of the Sleepstrip™ in postal screening for obstructive sleep apnoea
Authors: Hollingworth Linda , Tooby Mary , Roberts Deborah , Hanning Christopher D. 
Published: May 2003

SummaryThe SleepStrip™, a disposable screening device for the detection of obstructive sleep apnoea (OSA), which displays an estimated apnoea–hypopnoea index (AHISS) was posted, with instructions, to 48 patients referred for sleep study for suspected OSA. The patients subsequently underwent a cardiorespiratory sleep study from which the AHIE was derived. Thirty patients (63%) returned the SleepStrip™, the device displayed an AHISS in 22 patients (73%), of which 17 (57%) was deemed valid by the device. Twelve of the 30 patients who returned the SleepStrip™ had an AHIE ≥ 20 on the detailed sleep study. Of these, the SleepStrip™ recording was valid in seven of which only two had an AHISS ≥ 20. We concluded that the SleepStrip™ was not suitable for unsupervised postal screening for OSA.
The effect of sleep loss on next day effort
Authors: Engle‐Friedman Mindy , Riela Suzanne , Golan Rama , Ventuneac Ana M. , Davis Christine M. , Jefferson Angela D. , Major Donna 
Published: May 2003

SummaryThe study had two primary objectives. The first was to determine whether sleep loss results in a preference for tasks demanding minimal effort. The second was to evaluate the quality of performance when participants, under conditions of sleep loss, have control over task demands. In experiment 1, using a repeated‐measures design, 50 undergraduate college students were evaluated, following one night of no sleep loss and one night of sleep loss. The Math Effort Task (MET) presented addition problems via computer. Participants were able to select additions at one of five levels of difficulty. Less‐demanding problems were selected and more additions were solved correctly when the participants were subject to sleep loss. In experiment 2, 58 undergraduate college students were randomly assigned to a no sleep deprivation or a sleep deprivation condition. Sleep‐deprived participants selected less‐demanding problems on the MET. Percentage correct on the MET was equivalent for both the non‐sleep‐deprived and sleep‐deprived groups. On a task selection question, the sleep‐deprived participants also selected significantly less‐demanding non‐academic tasks. Increased sleepiness, fatigue, and reaction time were associated with the selection of less difficult tasks. Both groups of participants reported equivalent effort expenditures; sleep‐deprived participants did not perceive a reduction in effort. These studies demonstrate that sleep loss results in the choice of low‐effort behavior that helps maintain accurate responding.
Computerized calculation scheme for bitoric eikonic intraocular lenses
Authors: Langenbucher Achim , Seitz Berthold 
Published: May 2003

AbstractDespite full correction of the corneal astigmatism with toric intraocular lenses, the retinal image is distorted and the lateral image‐object magnification is different in different meridians. The purpose of this study is to describe an iteration strategy for tracing an axial pencil of rays through the ‘optical system eye’ containing astigmatic refractive surfaces with their axes at random to calculate a thick bitoric lens implant which eliminates image distortion. The capabilities of this computing scheme are demonstrated with two clinical examples. We present a mathematically straightforward computer‐based strategy for the calculation of thick bitoric eikonic lens implants. The iteration algorithm is initialized with a spherical front and a toric back surface and stepwise decreases the image distortion by adding cylinder lenses to the front lens surface corrected by the toric lens back surface. Total magnification can be modulated by varying the front‐to‐back surface power of the thick lens.
Open‐ and closed‐loop regressions compared in myopic and emmetropic subjects
Authors: Hazel Charlotte A. , Strang Niall C. , Vera‐Díaz Fuensanta A. 
Published: May 2003

AbstractPost‐near task accommodation regressions have been measured in a number of studies to investigate the association between myopia and nearwork. The slow nature of the regression found when measuring both open‐ and closed‐loop regressions in some subjects has been hypothesised to be associated with myopia development and progression. However, it is not known whether the speed and characteristics of the regression for an individual is the same under open‐ and closed‐loop conditions. In this study we measured post‐near task accommodation regression functions under open‐ and closed‐loop conditions for myopic and emmetropic subjects. We compared the responses of each subject under the two conditions and found that some subjects responded differently depending on the condition (i.e. a fast regression under one condition and a slow regression under the other condition). When compared as a group, the myopic subjects showed significantly more prolonged open‐loop regressions than closed‐loop regressions. In terms of the effect on the post‐task accommodation, the myopes appear to be more affected by the measurement conditions than the emmetropes in this study. The results highlight the importance of the type of accommodation stimulus when investigating the accommodation response.
A Simple Method to Identify Sleep Apnea Using Holter Recordings
Authors: Stein Phyllis K. , Duntley Stephen P. , Domitrovich Peter P. , Nishith Pallavi , Carney Robert M. 
Published: May 2003

Introduction: Despite its severe cardiovascular and other consequences, sleep apnea syndrome frequently is undiagnosed. Because apneas result in repeated autonomic arousals associated with cyclic variations in heart rate (CVHR), we hypothesized that sleep apnea syndrome could be identified from simple HR tachograms (graphs of HR vs time) derived from ECG monitoring.
Methods and Results: HR tachograms were generated from 57 digitized ECGs (46 clinical patients undergoing diagnostic studies and 11 research subjects) obtained during overnight polysomnography. Thirty‐three had significant sleep apnea syndrome (apnea‐hypopnea index ≥15). Eight patients had simultaneous Holter recordings during sleep studies (3 with digitized ECGs and 5 with paper ECGs). Duration of CVHR on tachograms was determined. CVHR patterns were characterized as high amplitude (HR changes ≥20 beats/min per cycle) versus lower amplitude (6–19 beats/min per cycle); or regular (in frequency, amplitude, and morphology) versus irregular. Tachograms were classified as having visible HR changes versus not visible (flat). Twenty‐four studies proved to be split‐night, so CVHR was quantified for the first 3 hours of each study only. When subjects were dichotomized into shorter (<20%, <36 min) and longer (≥20%) durations of CVHR, longer CVHR had a positive predictive accuracy of 86% for significant sleep apnea syndrome and 100% for abnormal sleep. When flat tachograms were excluded, negative predictive accuracy for shorter CVHR was 100%. All patients

(N = 13)

with >36 min high‐amplitude CVHR had significant obstructive sleep apnea. All predictions from Holter‐only data were concordant with clinical diagnoses.
Conclusion: HR tachogram patterns derived from ambulatory ECGs provide a simple method for identifying sleep apnea syndrome and other sleep disturbances in patients without major autonomic dysfunction.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 467‐473, May 2003)
Novel Concept of Atrial Tachyarrhythmias Originating from the Superior Vena Cava:
Authors: Liu Tu‐Ying , Tai Ching‐Tai , Lee Pi‐Chang , Hsieh Ming‐Hsiung , Higa Satoshi , Ding Yu‐An , Chen Shih‐Ann 
Published: May 2003

Introduction: Information about the activation patterns inside the superior vena cava (SVC) and entry and exit sites at the SVC‐right atrial (RA) junction during SVC tachyarrhythmia is limited.
Methods and Results: A detailed characterization of electrophysiologic mechanisms and ablation strategies was performed using a noncontact three‐dimensional mapping system in two cases of SVC tachycardia. The first case demonstrated SVC tachycardia originating from an ectopic focus inside the SVC, with sustained depolarization and conduction to the atrium. Entry and exit sites across the SVC‐RA junction were located very close to each other. The second case demonstrated two different reentrant circuits, one inside the SVC and the other into and out of the SVC‐RA junction. The entry and exit sites were located far away from each other.
Conclusion: Noncontact mapping may help to reveal the mechanism of SVC tachyarrhythmias and to locate entry and exit sites at the SVC‐RA junction as a guide for catheter ablation.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 533‐539, May 2003)
Natural History of Brugada Syndrome:
Authors: Brugada Pedro , Brugada Ramon , Mont Lluis , Rivero Maximo , Geelen Peter , Brugada Josep 
Published: May 2003

Introduction: The prognostic value of electrophysiologic studies in individuals with the syndrome of right bundle branch block and ST segment elevation in precordial leads V1 to V3 (Brugada syndrome) remains controversial. Our previous data from 252 individuals with the syndrome suggested that programmed ventricular stimulation had a good overall accuracy to predict events. However, studies from independent investigators questioned our results. We report here the largest population with Brugada syndrome ever studied by programmed electrical stimulation of the heart.
Methods and Results: Four hundred forty‐three individuals with an ECG diagnostic of Brugada syndrome were studied by programmed electrical stimulation of the heart. The diagnosis was made because of the classic ECG showing a coved‐type ST segment elevation in precordial leads V1 to V3. Of the 443 individuals, 180 had developed spontaneous symptoms (syncope or aborted sudden cardiac death) and 263 were asymptomatic at the time the diagnosis was made. The ventricular stimulation protocol included a minimum of two basic pacing cycle lengths with two ventricular premature beats from the right ventricular apex. A sustained ventricular arrhythmia was induced in 217 cases (49%). Symptomatic patients were more frequently inducible [126/180 (70%)] than asymptomatic individuals [91/263 (34%);

P = 0.0001

]. Males were more frequently inducible than females (54% vs 32%,

P < 0.0001

). Inducible individuals had a longer HV interval than noninducible patients (

50 ± 12 msec

vs

46 ± 10 msec, P < 0.002

). HV interval and number of premature beats needed to induce VF were not related to outcome. Inducibility was statistically a powerful predictor of arrhythmic events during follow‐up. Sixty of 217 inducible patients (28%) had spontaneous ventricular fibrillation compared with 5 of 221 noninducible patients

(2%; P = 0.0001)
.
Conclusion: Inducibility of sustained ventricular arrhythmias during programmed ventricular stimulation of the heart is a good predictor of outcome in Brugada syndrome.
(J Cardiovasc Electrophysiol, Vol. 14, pp. 455‐457, May 2003)
Complete Sequence and Comparative Analysis of the Genome of Herpes B Virus (
Cercopithecine Herpesvirus 1
) from a Rhesus Monkey
Authors: Perelygina Ludmila , Zhu Li , Zurkuhlen Holley , Mills Ryan , Borodovsky Mark , Hilliard Julia K. 
Published: May 2003

ABSTRACT

The complete DNA sequence of herpes B virus
(Cercopithecine herpesvirus 1)
strain E2490, isolated from a rhesus macaque, was determined. The total genome length is 156,789 bp, with 74.5% G+C composition and overall genome organization characteristic of alphaherpesviruses. The first and last residues of the genome were defined by sequencing the cloned genomic termini. There were six origins of DNA replication in the genome due to tandem duplication of both
oriL
and
oriS
regions. Seventy-four genes were identified, and sequence homology to proteins known in herpes simplex viruses (HSVs) was observed in all cases but one. The degree of amino acid identity between B virus and HSV proteins ranged from 26.6% (US5) to 87.7% (US15). Unexpectedly, B virus lacked a homolog of the HSV γ
1
34.5 gene, which encodes a neurovirulence factor. Absence of this gene was verified in two low-passage clinical isolates derived from a rhesus macaque and a zoonotically infected human. This finding suggests that B virus most likely utilizes mechanisms distinct from those of HSV to sustain efficient replication in neuronal cells. Despite the considerable differences in G+C content of the macaque and B virus genes (51% and 74.2%, respectively), codons used by B virus are optimal for the tRNA population of macaque cells. Complete sequence of the B virus genome will certainly facilitate identification of the genetic basis and possible molecular mechanisms of enhanced B virus neurovirulence in humans, which results in an 80% mortality rate following zoonotic infection.
Resolution of Parvovirus Dimer Junctions Proceeds through a Novel Heterocruciform Intermediate
Authors: Cotmore Susan F. , Tattersall Peter 
Published: May 2003

ABSTRACT

The minute virus of mice initiator protein, NS1, excises new copies of the left viral telomere in a single sequence orientation, dubbed flip, during resolution of the junction between monomer genomes in palindromic dimer intermediate duplexes. We examined this reaction in vitro using both
32
P-end-labeled linear substrates and similar unlabeled templates labeled by incorporation of [α-
32
P]TTP during the synthesis. The observed products suggest a resolution model that explains conservation of the hairpin sequence and in which a novel heterocruciform intermediate plays a crucial role. In vitro, NS1 initiates two replication pathways from OriL
TC
, the single active origin embedded in one arm of the dimer junction. NS1-mediated nicking liberates a base-paired 3′ nucleotide to prime DNA synthesis and, in a reaction we call “read-through synthesis,” forks established while the substrate is a linear duplex synthesize DNA in the flop orientation, leading to DNA amplification but not to junction resolution. Nicking leaves NS1 covalently attached to the 5′ end of the DNA, where it can serve as a 3′-to-5′ helicase, unwinding the NS1-associated strand. In the second pathway, resolution substrates are created when such unwinding induces the palindrome to reconfigure into a cruciform prior to fork assembly. New forks can then synthesize DNA in the flip orientation, copying one cruciform arm and creating a heterocruciform intermediate. Resolution proceeds via hairpin transfer in the extended arm of the heterocruciform, which releases one covalently closed duplex telomere and a partially single-stranded junction intermediate. We suggest that the latter intermediate is finally resolved via an NS1-induced single-strand nick at the otherwise inactive origin, OriL
GAA
.