bluuebunny/crossref_metadata_2025_split huggingface dataset:
A confirmatory factor analysis evaluation of the coronary heart disease risk factors of metabolic syndrome with emphasis on the insulin resistance factor
Authors: Novak S. , Stapleton L. M. , Litaker J. R. , Lawson K. A. 
Published: November 2003

Aim:  The goals of this study were: (1) to analyse the underlying associations between coronary risk factors and the metabolic syndrome and (2) to evaluate the construct validity of the variables used to measure each factor.Methods:  The subjects were from a previously studied cohort of 284 middle‐aged Caucasian males from Goteborg, Sweden, who were selected from the National Population Register. A confirmatory factor analysis was performed using EQS Multivariate Software Version 5.7b with maximum likelihood estimation. Hypertension, obesity, insulin resistance and hyperlipidaemia were the latent factors hypothesized.Results:  The final, four‐factor model showed good fit, with significant intercorrelations noted between all factors. The highest correlations were noted between the insulin resistance factor and the obesity factor (r = 0.887) and the insulin resistance factor and the lipid factor (r = 0.835). All factors exhibited good values for construct reliability and variance extracted except for the insulin resistance factor, which was measured with the variables of fasting insulin and fasting glucose levels.Conclusions:  A four‐factor model of metabolic syndrome including the coronary heart disease risk factors of hypertension, obesity, insulin resistance and hyperlipidaemia was developed using this sample of European, middle‐aged Caucasian males. Insulin resistance was not well defined using the variables of fasting insulin and fasting glucose levels. Other possible variables to include in the measurement of this factor are discussed.
SEM studies on the early larval development of Triops cancriformis (Bosc)(Crustacea: Branchiopoda, Notostraca)
Authors: Møller Ole S. , Olesen Jørgen , Høeg Jens T. 
Published: November 2003

AbstractWe investigated early larval development in the notostracan Triops cancriformis (Bosc, 1801–1802) raised from dried cysts under laboratory conditions. We document the five earliest stages using scanning electron microscopy. The stage I larva is a typical nauplius, lecithotropic and without trunk limbs. The stage II larva is feeding and has trunk limb precursors and a larger carapace. Stage III larvae have larger trunk limbs and a more adult shape. Stage IV larvae have well developed trunk limbs, and stage V larvae show atrophy of the antennae. We describe the ontogeny of selected features such as trunk limbs and carapace, discuss ontogeny and homologization of head appendages, follow the development of the feeding mechanism, and discuss trunk limb ontogeny.
The subepithelial gland in ants: a novel exocrine gland closely associated with the cuticle surface
Authors: Gobin Bruno , Ito Fuminori , Billen Johan 
Published: November 2003

AbstractTwo glandular systems were discovered that secrete their products onto the cuticular surface in ants. The first, the subepithelial gland, was previously undescribed in ants, and is found throughout the body just beneath the epithelium. This gland consists of independent secretory units, each made up of a single gland cell and an associated duct cell that penetrates the cuticle. Its ultrastructural appearance is consistent with possible hydrocarbon production. Examining 84 ant species, the subepithelial gland was found in eight subfamilies (out of 13), although not necessarily in all species. In a single ant species, Harpegnathos saltator, it was the epithelium itself that was enlarged and functioned as a gland. The enlarged epithelial cells secrete their products directly onto the cuticle through distinct cuticular crevasses.
The effects of kin and familiarity on interactions between fish
Authors: Ward Ashley J W , Hart Paul J B 
Published: November 2003

AbstractFish have been shown to discriminate between individuals on very general bases such as species, body length and colour. More recently, evidence has been accumulating from a number of species that relatedness and familiarity may be extremely important in mediating a range of interactions between individual fish. Studies have shown that fish are able to recognize kin and/or familiars, and that this ability potentially conveys significant benefits, including increased inclusive fitness, reduced inbreeding costs, reduced competition and enhanced antipredator behaviour. Here, we review the literature and consider future directions and applications for this research.
Co‐evolution in Strategic Renewal Behaviour of British, Dutch and French Financial Incumbents: Interaction of Environmental Selection, Institutional Effects and Managerial Intentionality*
Authors: Flier Bert , Bosch Frans A. J. Van Den , Volberda Henk W. 
Published: November 2003

abstractHow do incumbent firms and environments co‐evolve and how are firm‐level adaptation and selection at industry level interrelated? Can and do large established organizations renew themselves to adapt to their environment? Three single‐lens theories, relating to environmental selection, institutional theory, managerial intentionality, and a co‐evolutionary perspective are used to investigate strategic renewal of incumbent firms. We derive propositions and distinguish between three dimensions of strategic renewal and develop metrics to investigate our propositions in a multi‐level, multi‐country, longitudinal study of the European financial services industry.Our results provide the following insights. From an environmental selection perspective, we found incumbents have a preference for exploitation renewal actions. Country institutional environments appear to explain to what extent incumbents prefer internal and/or external renewal actions. Managerial intentionality seems to explain outlier behaviour and firm‐specific frequency and timing of renewal actions. From a co‐evolutionary perspective, interaction effects explain deviations from predictions derived from the single‐lens theories applied in this paper.
Spontaneous ‘baroreflex sequences’ occur as deterministic functions of breathing phase
Authors: Rothlisberger Brian W. , Badra Leslie J. , Hoag Jeffrey B. , Cooke William H. , Kuusela Tom A. , Tahvanainen Kari U.O. , Eckberg Dwain L. 
Published: November 2003

SummaryParallel increases or decreases of systolic pressures and R–R intervals occur spontaneously in healthy resting humans, and are thought to be expressions of vagal baroreflex physiology. We studied ten healthy supine young adults, and tested the null hypothesis that spontaneous baroreflex sequences are distributed uniformly throughout the breathing cycle. We recorded the electrocardiogram, photoplethysmographic arterial pressure, respiration (pneumobelt), and peroneal nerve muscle sympathetic activity in supine subjects who breathed spontaneously, or held their breaths in inspiration after 2 min of hyperventilation with 100% oxygen. We analysed pairs of three or more increasing or decreasing systolic pressures and R–R intervals with linear regression, and related the gain and timing of the onset of such sequences to the phase of respiration, and to preceding muscle sympathetic nerve activity. We found that baroreflex sequences occur erratically, at a frequency about one‐third that of breathing. However, when baroreflex sequences do occur, the timing of their onset is dictated by the phase of respiration. Parallel increases of systolic pressures and R–R intervals (‘up’ sequences) begin just before and after the beginning of expiration, and parallel decreases of systolic pressures and R–R intervals (‘down’ sequences) begin during late expiration and inspiration. Average gains of up and down baroreflex sequences triggered by muscle sympathetic bursts are comparable during breathing and apnoea. However, the latencies between sympathetic bursts and baroreflex sequences are less during breathing than during apnoea. We propose that parallel systolic pressure – R–R interval sequences are expressions of arterial baroreflex physiology, and that the nearly fixed timing of such sequences within breaths reflects simply respiratory gating of muscle sympathetic bursts.
Circulating norepinephrine and cerebrovascular control in conscious humans
Authors: Kimmerly D. S. , Tutungi E. , Wilson T. D. , Serrador J. M. , Gelb A. W. , Hughson R. L. , Shoemaker J. K. 
Published: November 2003

SummaryBackground:  Cerebral vasoconstriction without concurrent changes in systemic arterial blood pressure has been observed in both normal individuals and those with idiopathic orthostatic intolerance following several minutes of postural stress when circulating catecholamines are elevated. Therefore, we tested the hypothesis that α‐adrenergic activation with and without elevated circulating norepinephrine (NE) directly affects cerebrovascular tone in healthy individuals.Methods:  Mean arterial pressure (MAP; tonometry) and cerebral blood flow velocity (MFV) in the middle cerebral artery (transcranial Doppler) were measured in seven healthy individuals during 15 min periods of saline and of 50 (low NE) and 100 (high NE) ng kg−1 min−1 infusions of NE. Following this, phentolamine (PHO) was administered to return MAP back to baseline while high NE infusion continued (high NE + PHO). Finally, NE infusion was stopped allowing the persistent effects of PHO to dominate.Results:  Circulating NE caused a dose‐dependent increase in MAP (P<0·05). During combined high NE + PHO, blood pressure was initially reduced to baseline levels but then increased a second time (P<0·05) during the final ∼5 min of this phase. MFV remained constant during both low NE and high NE. In contrast, the secondary increase in BP during the late high NE + PHO phase was associated with elevated MFV. Cerebral vascular resistance (CVR) increased during high NE but was reduced to baseline during both early and late portions of the combined high NE + PHO phase (i.e. despite the late‐phase increase in blood pressure).Conclusions:  The increase in CVR during NE infusion was explained by an autoregulatory response to the increased blood pressure and not an α‐mediated constriction. However, PHO appeared to interfere with the normal autoregulatory response to increasing blood pressure.
Prognostic predictors for survival in patients with COPD using cardiopulmonary exercise testing
Authors: Hiraga Toru , Maekura Ryoji , Okuda Yoshinari , Okamoto Takashi , Hirotani Atsushi , Kitada Seigo , Yoshimura Kenji , Yokota Soichiro , Ito Masami , Ogura Takeshi 
Published: November 2003

SummaryWe studied the relationship between physiologic parameters in cardiopulmonary exercise testing (CPET) and prognosis in terms of survival time in patients with chronic obstructive pulmonary disease (COPD) in order to accurately assess the severity of the disease. From a group of 195 patients with COPD who had consecutively undergone CPET between July 1989 and October 1997, we enrolled 120 subjects (mean age 67·6 years, 104 males) with exertional dyspnoea into a cohort protocol. Of these subjects, 34 (28·3%) died during the 3–5‐year follow‐up period after CPET. By univariate analysis, the following factors were significantly associated with survival time: age, body mass index, %FVC, %FEV1, FEV1%, Paco2 at rest, severity of exercise‐induced hypoxemia evaluated by ΔPao2/ΔV̇o2 (Pao2‐slope), oxygen uptake, ventilation, tidal volume, Paco2 and oxygen pulse at maximum exercise, as well as prescribing long‐term oxygen therapy. By multivariate analysis, age and the Pao2‐slope showed significance as independent prognostic factors, and the Pao2‐slope was most closely associated with the survival time. These results reveal that CPET is a useful technique to accurately assess the relationship between the functional impairments and the prognosis of patients with COPD.
Influence of oxygen administration on pulmonary haemodynamics and tissue oxygenation during exercise in COPD patients with different ACE genotypes
Authors: Kanazawa Hiroshi , Hirata Kazuto , Yoshikawa Junichi 
Published: November 2003

SummaryWe previously found that the angiotensin‐converting enzyme (ACE) DD genotype is associated with exaggerated pulmonary hypertension and disturbance of tissue oxygenation during exercise in chronic obstructive pulmonary disease (COPD) patients. This study was designed to compare the effect of oxygen administration on pulmonary haemodynamics and tissue oxygenation during exercise in COPD patients with different ACE genotypes. Forty‐three COPD patients (II = 16, ID = 12, DD = 15) underwent right heart catheterization, and then performed an exercise test with room air or oxygen. We measured pulmonary haemodynamic variables and indices of tissue oxygenation such as mixed venous oxygen tension (Pvo2) and arterial lactate concentration, both at rest and after exercise. The magnitude of difference in mean pulmonary arterial pressure and pulmonary vascular resistance after exercise between breathing of room air and breathing of oxygen did not significantly differ among the three groups. Pvo2 after exercise with room air or oxygen was significantly higher in patients with the II genotype than in those with the ID or DD genotype. In contrast, lactate concentration after exercise with room air or oxygen was significantly lower in patients with the II genotype than in those with the ID or DD genotype. Moreover, the magnitude of difference in Pvo2 and lactate concentration after exercise between breathing of room air and breathing of oxygen was the II > ID > DD genotype. These findings suggest that the ability of oxygen administration to improve tissue oxygenation during exercise is associated with the ACE genotypes in COPD patients.
Quantification of inspiratory‐induced vasoconstrictive episodes: a comparison of laser Doppler fluxmetry and photoplethysmography
Authors: Rauh Robert , Posfay Alexander , Mück‐Weymann Michael 
Published: November 2003

SummaryLaser Doppler fluxmetry (LDF) or photoplethysmography (PPG) are frequently used as non‐invasive tools to assess skin blood flow. They are both thought to be suitable and interchangeable methods for the detection of sympathetically activated vasoconstrictive episodes that can be provoked by a voluntary deep inspiration (DI), the so‐called inspiratory gasp response (IGR). However, a rigorous comparison of the two methods has not been reported in the literature. The aim of this study was to compare the detection of IGR with LDF and PPG. We investigated 14 healthy volunteers (five female, nine male, 25·4 ± 2·7 years). A PPG probe was applied to the tip of the thumb of the dominant hand, a LDF sensor to the tip of the adjacent index finger. After adaptation and baseline measurements the subjects were asked to perform a DI with time intervals of 90, 60, 30 and 15 s. We found that both methods are useful to detect individual IGR. Overall correlation of IGR amplitude detected with LDF and PPG was significant (r = 0·433). Surprisingly, there was a continuous increase of the correlation coefficient from the first (r = 0·105) or second (r = −0·184) IGR to the fifth (r = 0·727) IGR. This implies that experimental data obtained with PPG and LDF are not equivalent and that one has to be cautious regarding the comparison and interpretation of results obtained with these two different methods.
Maximum rate of oxygen consumption related to succinate dehydrogenase activity in skeletal muscle fibres of chronic heart failure patients and controls
Authors: Bekedam Martijn A. , Van Beek‐Harmsen Brechje J. , Boonstra Anco , Van Mechelen Willem , Visser Frans C. , Van Der Laarse Willem J. 
Published: November 2003

SummaryPrevious studies indicate that the low maximum rate of oxygen consumption (VO2max) of chronic heart failure (CHF) patients is not because of impaired pump function of the heart. We hypothesize that VO2 during maximum exercise is determined by the total oxidative capacity of skeletal muscle. VO2max of six controls and 14 CHF patients, New York Heart Association class I–III, was determined using an incremental bicycle ergometer test. Cryostat sections of a biopsy from the quadriceps femoris muscle were incubated for succinate dehydrogenase (SDH) using quantitative histochemistry. VO2max (range: 29 ml O2 kg min−1 in a class III patient to 118 ml O2 kg min−1 in a control subject) correlates with the mean SDH activity of skeletal muscle fibres (r = 0·79 or r = 0·81, including or excluding oxygen uptake at rest, respectively; P<0·001). The relationship between VO2max and SDH activity is similar to that determined previously using isolated single muscle fibres and myocardial trabeculae under hyperoxic conditions. From the product of SDH activity and the cross‐sectional area of the fibre (i.e. spatially integrated SDH activity), it is possible to calculate the maximum oxygen uptake rate per unit muscle fibre length. This uptake rate is linearly related to the number of capillaries per fibre (r = 0·76, P<0·001) in all subjects, suggesting that oxidative capacity of skeletal muscle fibres in CHF patients decreases in proportion to the oxygen supply capacity of the microcirculation.
Injurious ventilation strategies cause systemic release of IL‐6 and MIP‐2 in rats in vivo*
Authors: Haitsma Jack J. , Uhlig Stefan , Verbrugge Serge J. , Göggel Rolf , Poelma Davey L. H. , Lachmann Burkhard 
Published: November 2003

Summary In vivo experiments showed no increased production of tumour necrosis factor (TNF) in response to injurious ventilation strategies in otherwise untreated animals. Because interleukin‐6 (IL‐6) and macrophage inflammatory protein‐2 (MIP‐2) are more sensitive markers of ventilation‐induced cytokine release, serum and bronchoalveolar lavage (BAL) samples were examined for these mediators. Eighty‐five adult rats were randomized to three different ventilation strategies. Rats were ventilated with low pressures and low tidal volumes [13/3; peak inspiratory pressure (PIP)/positive end‐expiratory pressure (PEEP) in cmH2O], the second group of rats was ventilated with high pressures and low PEEP resulting in high tidal volumes (32/6), and the third group was ventilated with the same high pressures but without PEEP (32/0). Animals were ventilated either for 90 or 240 min, subsequently serum and BAL were collected for analyses on IL‐6 and MIP‐2 content. Non‐ventilated animals served as healthy controls. Ventilation with 32/0 for 90 or 240 min, led to increased serum IL‐6 levels. Serum MIP‐2 levels were increased by ventilation with 32/6 (90 min) and 32/0 (240 min). Ventilation under any condition, even at 13/3, resulted in elevated MIP‐2 levels in the BAL fluid. Even at normal pressures pulmonary MIP‐2 levels were increased, suggesting that ventilation may promote pro‐inflammatory responses in healthy subjects.
Heel skin hyperaemia: direct compression versus vascular occlusion
Authors: Mayrovitz Harvey N. , Sims Nancy , Dribin Lori 
Published: November 2003

SummaryVulnerability of the heel to ulceration in bed‐bound persons is related to direct pressure‐induced blood flow decreases. Periodic pressure reduction is a clinical strategy to help prevent ulcers by allowing flow‐repayment hyperaemia that has a magnitude and duration thought to be related to the duration of the prior interval of ischaemia. However, there are reasons to question whether effects of flow stoppages caused by direct tissue loading are similar to those because of ischaemia without superimposed direct pressure. This question was investigated by comparing posterior heel skin blood flow responses via laser‐Doppler perfusion monitoring of 27 supine‐lying subjects in whom blood flow was reduced by 5‐min of direct heel loading on a support surface and by 5‐min of ankle‐cuff compression. Results showed that blood flow reductions were the same for both methods but the hyperaemia was significantly greater when flow reduction was produced by direct heel loading. This was true for ratio of peak hyperaemic flow to baseline (8·20 ± 1·32 s versus 4·68 ± 0·80 s, P≤0·001), hyperaemic to baseline 3‐min flow‐time area ratios (4·70 ± 0·65 s versus 1·95 ± 0·29 s, P≤0·001) and for total hyperaemia durations (352 ± 39 s versus 181 ± 14 s, P<0·001). These findings raise new questions regarding the precise physiological effects of heel and tissue loading in general, the factors that contribute to the hyperaemic response and their clinical impact and interpretation. Possible sources of the observed greater post‐loading hyperaemia responses are discussed.
Is the International Convergence of Capital Adequacy Regulation Desirable?
Authors: Acharya Viral V. 
Published: November 2003

AbstractThe merit of international convergence of bank capital requirements in the presence of divergent closure policies of different central banks is examined. The lack of a complementary variation between minimum bank capital requirements and regulatory forbearance leads to a spillover from more forbearing to less forbearing economies and reduces the competitive advantage of banks in less forbearing economies. Linking the central bank's forbearance to its alignment with domestic bank owners, it is shown that in equilibrium, a regression toward the worst closure policy may result: The central banks of initially less forbearing economies also adopt greater forbearance.
TheTIME FOR COFFEEGene Maintains the Amplitude and Timing of Arabidopsis Circadian Clocks[W]
Authors: Hall Anthony , Bastow Ruth M. , Davis Seth J. , Hanano Shigeru , McWatters Harriet G. , Hibberd Victoria , Doyle Mark R. , Sung Sibum , Halliday Karen J. , Amasino Richard M. , Millar Andrew J. 
Published: November 2003

AbstractPlants synchronize developmental and metabolic processes with the earth's 24-h rotation through the integration of circadian rhythms and responses to light. We characterize the time for coffee (tic) mutant that disrupts circadian gating, photoperiodism, and multiple circadian rhythms, with differential effects among rhythms. TIC is distinct in physiological functions and genetic map position from other rhythm mutants and their homologous loci. Detailed rhythm analysis shows that the chlorophyll a/b-binding protein gene expression rhythm requires TIC function in the mid to late subjective night, when human activity may require coffee, in contrast to the function of EARLY-FLOWERING3 (ELF3) in the late day to early night. tic mutants misexpress genes that are thought to be critical for circadian timing, consistent with our functional analysis. Thus, we identify TIC as a regulator of the clock gene circuit. In contrast to tic and elf3 single mutants, tic elf3 double mutants are completely arrhythmic. Even the robust circadian clock of plants cannot function with defects at two different phases.