bluuebunny/crossref_metadata_2025_split huggingface dataset:
Treatment with intravenous insulin followed by continuous subcutaneous insulin infusion improves glycaemic control in severely resistant Type 2 diabetic patients
Authors: Pouwels M.‐J. J. , Tack C. J. , Hermus A. R. , Lutterman J. A. 
Published: March 2003

AbstractAims Despite high‐dose s.c. insulin therapy, some Type 2 diabetes mellitus (DM) patients remain in poor metabolic control. We investigated whether a period of euglycaemia using i.v. insulin, followed by continuous subcutaneous insulin infusion (CSII), would ameliorate the deleterious effects of hyperglycaemia on insulin sensitivity and result in sustained, improved metabolic control.Methods In a prospective observational study, eight Type 2 DM patients with severe insulin resistance (insulin dose 1.92 ± 0.66 U/kg per day (mean ±sd)), in poor metabolic control (HbA1c 12.0 ± 1.7%), were treated with i.v. insulin for 31 ± 10 days aimed at euglycaemia, followed by CSII therapy for 12 months, using insulin lispro. Before and after 28 ± 6 days of i.v. insulin treatment, insulin sensitivity was measured by a hyperinsulinaemic euglycaemic clamp.Results Euglycaemia was reached after 12 ± 6 days of i.v. insulin treatment. Subsequently, the i.v. insulin dose required to maintain euglycaemia decreased from 1.7 ± 0.9 to 1.1 ± 0.6 U/kg per day (P < 0.005). Whole body glucose uptake increased from 12.7 ± 5.7 to 22.4 ± 8.8 µmol/kg per min (P < 0.0005). HbA1c decreased to 8.9 ± 1.2% after 28 ± 6 days, to 7.1 ± 0.6% after 6 months and to 8.3 ± 1.4% after 12 months (P < 0.001 vs. pretreatment, for all). Lipid profile improved and plasminogen activator inhibitor type 1 levels decreased significantly. Mean body weight did not change.Conclusions In Type 2 diabetic patients, who are poorly controlled despite high‐dose s.c. insulin treatment, a period of 2 weeks of euglycaemia achieved by i.v. insulin reverses hyperglycaemia‐induced insulin resistance and substantially improves metabolic control. Subsequent CSII treatment, using insulin analogues, appears to maintain improved metabolic control for at least 1 year. This approach is promising but needs further evaluation.
Impairment of cerebral autoregulation in diabetic patients with cardiovascular autonomic neuropathy and orthostatic hypotension
Authors: Mankovsky B. N. , Piolot R. , Mankovsky O. L. , Ziegler D. 
Published: March 2003

AbstractAims  Impaired cerebrovascular reactivity and autoregulation has been previously reported in patients with diabetes mellitus. However, the contribution of cardiovascular diabetic autonomic neuropathy and orthostatic hypotension to the pathogenesis of such disturbances is not known. The purpose of this study was to evaluate cerebral blood flow velocity in response to standing in patients with diabetes and cardiovascular autonomic neuropathy with or without orthostatic hypotension.Methods  We studied 27 patients with diabetes—eight had cardiovascular autonomic neuropathy and orthostatic hypotension (age 46.4 ± 13.5 years, diabetes duration 25.0 ± 11.0 years), seven had autonomic neuropathy without hypotension (age 47.3 ± 12.7 years, diabetes duration 26.4 ± 12.1 years), and 12 had no evidence of autonomic neuropathy (age 44.1 ± 13.8 years, diabetes duration 17.1 ± 10.2 years)—and 12 control subjects (age 42.6 ± 9.7 years). Flow velocity was recorded in the right middle cerebral artery using transcranial Doppler sonography in the supine position and after active standing.Results  Cerebral flow velocity in the supine position was not different between the groups studied. Active standing resulted in a significant drop of mean and diastolic flow velocities in autonomic neuropathy patients with orthostatic hypotension, while there were no such changes in the other groups. The relative changes in mean flow velocity 1 min after standing up were −22.7 ± 16.25% in patients with neuropathy and orthostatic hypotension, +0.02 ± 9.8% in those with neuropathy without hypotension, −2.8 ± 14.05% in patients without neuropathy, and −9.2 ± 15.1% in controls.Conclusions  Patients with diabetes and cardiovascular autonomic neuropathy with orthostatic hypotension show instability in cerebral blood flow upon active standing, which suggests impaired cerebral autoregulation.
Screening for Type 2 diabetes: is it worthwhile? Views of general practitioners and practice nurses
Authors: Whitford D. L. , Lamont S. S. , Crosland A. 
Published: March 2003

AbstractAims  Screening for Type 2 diabetes does not meet all the criteria for screening, yet is increasingly proposed. The views of health care professionals towards screening for Type 2 diabetes are not known. We set out to explore the attitudes and beliefs held by general practitioners (GPs) and practice nurses towards screening for Type 2 diabetes.Methods  Semistructured interviews with 10 GPs and nine practice nurses in eight general practices in North‐east England. Data collection and analysis proceeded in an iterative manner in accordance with grounded theory.Results  Practitioners who perceive themselves to be most aware of the evid‐ence base surrounding screening for Type 2 diabetes are least likely to support its introduction. Those who support screening for Type 2 diabetes hold a ‘common sense’ viewpoint that earlier detection must be better and believe that patients demand and respect early diagnosis. Practitioners acknowledge a lack of knowledge and skills to promote lifestyle changes. This deficiency is combined with workload issues, contributing towards a medicalized view of diabetes screening.Conclusions  The belief that screening for Type 2 diabetes is worthwhile is based not on evidence for the effectiveness of screening, but rather on a complex interaction of factors including perceptions of patient desires and an interplay of previous experience and evidence from other sources. Increased resources would be most likely to promote screening in primary care.
Modelling canopy CO2 fluxes: are ‘big‐leaf’ simplifications justified?
Authors: Friend A. D. 
Published: March 2003

Abstract

The ‘big‐leaf’ approach to calculating the carbon balance of plant canopies is evaluated for inclusion in the ETEMA model framework. This approach assumes that canopy carbon fluxes have the same relative responses to the environment as any single leaf, and that the scaling from leaf to canopy is therefore linear.
A series of model simulations was performed with two models of leaf photosynthesis, three distributions of canopy nitrogen, and two levels of canopy radiation detail. Leaf‐ and canopy‐level responses to light and nitrogen, both as instantaneous rates and daily integrals, are presented.
Observed leaf nitrogen contents of unshaded leaves are over 40% lower than the big‐leaf approach requires. Scaling from these leaves to the canopy using the big‐leaf approach may underestimate canopy photosynthesis by ~20%. A leaf photosynthesis model that treats within‐leaf light extinction displays characteristics that contradict the big‐leaf theory. Observed distributions of canopy nitrogen are closer to those required to optimize this model than the homogeneous model used in the big‐leaf approach.
It is theoretically consistent to use the big‐leaf approach with the homogeneous photosynthesis model to estimate canopy carbon fluxes if canopy nitrogen and leaf area are known and if the distribution of nitrogen is assumed optimal. However, real nitrogen profiles are not optimal for this photosynthesis model, and caution is necessary in using the big‐leaf approach to scale satellite estimates of leaf physiology to canopies. Accurate prediction of canopy carbon fluxes requires canopy nitrogen, leaf area, declining nitrogen with canopy depth, the heterogeneous model of leaf photosynthesis and the separation of sunlit and shaded leaves. The exact nitrogen profile is not critical, but realistic distributions can be predicted using a simple model of canopy nitrogen allocation.
The vertical distribution of pronophiline butterflies (Nymphalidae, Satyrinae) along an elevational transect in Monte Zerpa (Cordillera de Mérida, Venezuela) with remarks on their diversity and parapatric distribution
Authors: Pyrcz Tomasz W. , Wojtusiak Janusz 
Published: March 2003

AbstractAim The distribution of neotropical butterflies of the tribe Pronophilini (Lepidoptera, Satyridae) was analysed with the aim of determining (i) the elevational ranges of distribution of each species (ii) the elevational gradient in diversity, and (iii) the existence of parapatric distributions of some closely related species pairs.Location The field study was carried out in the middle and upper section of the valley of the Río Albarregas, a tributary of the Río Chama on the southern slopes of the Serranía de la Culata, in the central part of the Cordillera de Mérida, Venezuela.Methods The material was collected along an elevational transect set on a trail leading from Merida to the Páramo de Los Conejos in the area known as Monte Zerpa. It consisted of a series of 32 collection sites set at every 25 m of altitude and covered an elevation from 2250 m to 3025 m.Results The ranges of Lymanopoda obsoleta, L. albocincta, L. zapatoza, Corades chelonis, C. pannonia, C. medeba, Mygona irmina, Pedaliodes epidipnis, P. japhleta, P. montagna and P. panyasis were all restricted to the lower half of the cloud forest zone and L. diezti, C. pax, P. polla, P. ornata and P. ferratilis were all restricted to the upper part. Two species, Erethris porphyria and Steroma bega, crossed the entire elevational range of the cloud forest zone.The biodiversity, as measured by Shannon’s index, attained a maximum at 2700 m, beyond which it gradually decreased. A parapatric distribution was confirmed for three pairs of closely related species: L. obsoleta and L. diezti, C. chelonis and C. pax and P. montagna and P. ferratilis.Main conclusions The peak in diversity at middle elevations seems to result from the overlapping ranges of species distributed over lower and upper parts of the cloud forest. Correlation of species composition at particular transect sites with elevation showed that increase in elevation was associated with an increase in species composition difference. Post‐mating isolation was suggested as a primary factor responsible for maintaining the parapatric distributions of species occupying the upper and lower zones and preventing their respective distributions from expanding.
Patterns of diversity, depth range and body size among pelagic fishes along a gradient of depth
Authors: Smith Katherine F. , Brown James H. 
Published: March 2003

AbstractStudies of geographical patterns of diversity have focused largely on compiling and analysing data to evaluate alternative hypotheses for the near‐universal decrease in species richness from the equator to the poles. Valuable insights into the mechanisms that promote diversity can come from studies of other patterns, such as variation in species distributions with elevation in terrestrial systems or with depth in marine systems. To obtain such insights, we analysed and interpreted data on species diversity, depth of occurrence and body size of pelagic fishes along an oceanic depth gradient. We used a database on pelagic marine fishes native to the north‐east Pacific Ocean between 40°N and 50°N. We used data from the Pacific Rim Fisheries Program that were obtained from commercial, management and scientific surveys between 1999 and 2000. Depth of occurrence and maximum body length were used to assess the distributions of 409 species of pelagic fishes along a depth gradient from 0 to 8000 m. A presence–absence matrix was used to classify the depth range of each species into 100‐m intervals. Atmar & Patterson's (1995) software was used to quantify the degree of nestedness of species distributions. Pelagic fish species diversity decreased steeply with increasing depth; diversity peaked at less than 200 m and more than half of the species had mean depths of occurrence between 0 and 300 m. The distribution of species showed a very strong nested subset pattern along the depth gradient. Whereas species with narrow ranges were generally restricted to shallow waters, wide‐ranging species occurred from near the surface to great depths. The relationship between maximum body size and mean depth range differed between teleost and elasmobranch fishes: being positive for teleosts, but negative for elasmobranches. Results support hypotheses that some combination of high productivity and warm temperature promote high species diversity, and reject those that would attribute the pattern of species richness to the mid‐domain effect, habitat area, or environmental constancy. The data provided a clear example of Rapoport's rule, a negative correlation between average depth range and species diversity.
Pattern and process in the geographical ranges of freshwater fishes
Authors: Rosenfield Jonathan A. 
Published: March 2003

AbstractNorth American freshwater fishes were studied to determine whether they displayed the same relationships between log (geographical range size) and log (body size) and the same pattern of range shape as found among North American birds and mammals. The forces that produce these patterns were also investigated. The log (geographical range size) : log (body size) relationship was analysed for 121 North American freshwater fish species. Thirty‐two imperilled species were compared with 89 non‐imperilled species to determine if the overall relationship could result from differential extinction. Range geometries were analysed, within and among habitat guilds, to determine if general patterns could be detected. The log (geographical range size) : log (body size) pattern among freshwater fish species was triangular and qualitatively similar to that found for North American birds and mammals. The results suggest that below a minimum geographical range, the likelihood of extinction increases dramatically for freshwater fishes and that this minimum range size increases with body size. The pattern of fish species’ range shapes differs from that found for other North American vertebrate taxa because, on average, fish possess much smaller ranges than terrestrial species and most fish species’ geographical ranges extend further on a north–south axis than on an east–west axis. The log (geographical range size) : log (body size) pattern reveals that fish species’ geographical ranges are more constrained than those of terrestrial species. The triangular relationship may be caused by differential extinction of species with large bodies and small geographical ranges as well as higher speciation rates of small‐bodied fish. The restricted geographical ranges of freshwater fishes gives them much in common with terrestrial species on oceanic islands. Range shape patterns within habitat guilds reflect guild‐specific historical and current ecological forces. The overall pattern of range shapes emerges from the combination of ecologically different subunits.
Plant species richness of nature reserves: the interplay of area, climate and habitat in a central European landscape
Authors: Pyšek Petr , Kučera Tomáš , Jarošík Vojtěch 
Published: March 2003

AbstractAim To detect regional patterns of plant species richness in temperate nature reserves and determine the unbiased effects of environmental variables by mutual correlation with operating factors.Location The Czech Republic.Methods Plant species richness in 302 nature reserves was studied by using 14 explanatory variables reflecting the reserve area, altitude, climate, habitat diversity and prevailing vegetation type. Backward elimination of explanatory variables was used to analyse the data, taking into account their interactive nature, until the model contained only significant terms.Results A minimal adequate model with reserve area, mean altitude, prevailing vegetation type and habitat diversity (expressed as the number of major habitat types in the reserve) accounted for 53.9% of the variance in species number. After removing the area effect, habitat diversity explained 15.6% of variance, while prevailing vegetation type explained 29.6%. After removing the effect of both area and vegetation type, the resulting model explained 10.3% of the variance, indicating that species richness further increased with habitat diversity, and most obviously towards warm districts. After removing the effects of area, habitat diversity and climatic district, the model still explained 9.4% of the variance, and showed that species richness (i) significantly decreased with increasing mean altitude and annual precipitation, and with decreasing January temperature in the region of the mountain flora, and (ii) increased with altitudinal range in regions of temperate and thermophilous flora.Main conclusions We described, in quantitative terms, the effects of the main factors that might be considered to be determining plant species richness in temperate nature reserves, and evaluated their relative importance. The direct habitat effect on species richness was roughly equal to the direct area effect, but the total direct and indirect effects of area slightly exceeded that of habitat. It was shown that the overall effect of composite variables such as altitude or climatic district can be separated into particular climatic variables, which influence the richness of flora in a context‐specific manner. The statistical explanation of richness variation at the level of families yielded similar results to that for species, indicating that the system of nature conservation provides similar degrees of protection at different taxonomic levels.
Simulation of a putative susceptibility risk factor to explain the findings of the Heart and Estrogen/progestin Replacement Study (HERS)
Authors: Psaty Bruce M. , Cushman Mary , Rosendaal Frits R. 
Published: March 2003

AbstractIn the HERS trial, hormone therapy did not reduce the risk of coronary events. In post hoc analyses, treatment was associated with early harm and late benefit. According to one hypothesis, a risk factor may well distinguish a susceptible subgroup with early events associated with hormone therapy from a nonsusceptible subgroup who benefit from hormone therapy. In simulation studies, it appeared that only a susceptibility factor with a low prevalence (3–5%) and a high risk ratio (13–25‐fold) can produce the pattern of risks seen in HERS. The number of candidate factors is likely to be small.
Evidence for a quantitative trait locus for plasma fibrinogen from a family–based association study
Authors: Mayosi B. M. , Vickers M. A. , Green F. R. , Ratcliffe P. J. , Julier C. , Lathrop G. M. , Watkins H. , Keavney B. 
Published: March 2003

AbstractStudies in unrelated individuals have shown an association between fibrinogen gene polymorphisms and plasma fibrinogen levels, which is itself a risk factor for coronary heart disease. Family‐based studies have complementary strengths in the investigation of such hypothesized genetic associations. Genotypes at the β‐fibrinogen ‐455G/A promoter polymorphism, and a neighbouring highly polymorphic microsatellite in the α‐fibrinogen gene were examined for evidence of genetic linkage and association with plasma fibrinogen in 568 members of 97 Caucasian families. The heritability of plasma fibrinogen was 0.22 ± 0.08, P = 0.0007. There was no significant evidence of genetic linkage between the fibrinogen locus and plasma fibrinogen with either marker. In contrast, there was evidence for association of plasma fibrinogen with genotype at the β‐455G/A polymorphism (χ12 = 11.12; P = 0.0009). Tests examining allelic transmission from heterozygous parents confirmed this association (Monk’s test, T = 2.17; P = 0.03). Genotype at the β‐455G/A polymorphism accounted for 2% of the observed variation in fibrinogen. This is equivalent to about 10% of the heritable component, suggesting the presence of other quantitative trait loci (QTL) in unlinked genes. Confirmation of the association of plasma fibrinogen with genotype at the β‐455G/A polymorphism in families indicates that the association is due to the physical proximity of this marker to a QTL, although the effect of this QTL was too small to be detected by linkage in this study. These findings are of potential importance for the design of genetic studies of multifactorial quantitative traits.
Methods to identify population outliers using genetic markers
Authors: Fisher Sheila A. , Lewis Cathryn M. 
Published: March 2003

AbstractIntroduction  Genetic studies to identify linkage or association usually assume participants are sampled from a genetically homogeneous population, so that a single set of marker allele frequencies is appropriate for all individuals in the study.MethodsWe have developed a method to identify individuals who are population outliers, because the marker allele frequency distributions from which their genotypes arise differ from the distributions of the remaining individuals in the study. Using allele frequencies estimated from an independent sample, the genotype log likelihood (GLL) test statistic calculates the likelihood of each individual’s genotypes across all markers. Extreme values of the statistic indicate that the individual arises from a different population. The distribution of the test statistic is derived and its convergence under the central limit theorem discussed.Results and DiscussionThis method was applied to genome search data from rheumatoid arthritis which identified a single population outlier family. We used allele frequencies from different populations to show that 100 markers provides high power to identify outliers across a range of populations. The GLL test statistic can be used as a screening tool to identify outlier families in any genetic study with genotyping at independent markers.
Hunting became a secondary activity 2000 years ago: marine fishing did the same in 2021
Authors: Cury Philippe , Cayré Patrice 
Published: March 2003

Ghoti papersGhoti aims to serve as a forum for stimulating and pertinent ideas. Ghoti publishes succinct commentary and opinion that addresses important areas in fish and fisheries science. Ghoti contributions will be innovative and have a perspective that may lead to fresh and productive insight of concepts, issues and research agendas. All Ghoti contributions will be selected by the editors and peer reviewed. Etymology of Ghoti George Bernard Shaw (1856–1950), polymath, playwright, Nobel prize winner and the most prolific letter writer in history, was an advocate of English spelling reform. He was reportedly fond of pointing out its absurdities by proving that ‘fish’ could be spelt ‘ghoti’. That is: ‘gh’ as in ‘rough’, ‘o’ as in ‘women’ and ‘ti’ as in palatial.AbstractMan has been domesticating plants and animals for 10 000 years. Domestication increased so that 2000 years ago, following the ‘Neolithic’ or ‘food‐producing’ revolution, the overwhelming majority of people were making a living by farming. Nowadays hunting, an uncertain way of collecting food, has shifted from a survival activity to a secondary (and most often recreational) activity. Within less than a century, marine fisheries, which constitute the last major world industry exploiting wild animal resources, have reached many ecological and economic limits and they face many uncertainties. In the context of generalised overexploitation, fishing could rapidly follow the same history as hunting and become a marginal activity for the collection of luxury items. This is not only a major concern for the future of an important food source, it also seriously questions our ability to preserve our last and unique relationship with renewable wild animal resources. If we do not want fisheries to be the counterpart of hunting, fisheries and fisheries research need to be ‘modernised’ in a way amenable to integrating new objectives, paradigms and ethical concerns. As scientists, we must direct our efforts toward reconciling long‐term environmental objectives and short‐term constraints by defining new indicators and reference points for management. Will we be able to initiate a ‘human and wild food reconciliation’ revolution?