bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of recovery properties of desflurane and sevoflurane according to gender differences
Authors: Tercan E. , Kotanoglu M. S. , Yildiz K. , Dogru K. , Boyaci A.
Published: February 2005

Background:  The aim of this study was to investigate the recovery properties of desflurane and sevoflurane in patients undergoing elective surgery, according to the gender differences.

Methods:  In the study, 160 ASA class I–II patients aged between 20 and 60 years were included. The patients were assigned into two groups according to their gender, and these groups were randomly divided into two groups according to a selected volatile anaesthetic agent. Intraoperative bispectral index, time of postoperative achievement for end‐tidal concentrations of volatile agents to decline 50% (ET‐AA%50), time for extubation, time for eye opening and orientation, and time for bispectral index values to reach control values were recorded. Aldrete scores and error points of a delayed memory recall test were determined.

Results:  Desflurane groups had a shorter ET‐AA%50 time, extubation and eye‐opening time in male and female patients compared to the sevoflurane groups, and these results were statistically significant (P < 0.05). In both the desflurane and sevoflurane groups, ET‐AA%50 time, extubation and eye‐opening time were shorter in male patients than in female patients, and these results were also statistically significant (P < 0.05). There were no significant differences among the groups in terms of Aldrete scores and error points of delayed memory recall test (P > 0.05).

Conclusion:  In conclusion, early recovery time was shorter in male patients compared to female patients in both the desflurane and sevoflurane groups. Additionally, in the desflurane groups it was shorter in the sevoflurane groups for both genders.
Bi‐level positive airway pressure ventilation reduces the oxygen cost of breathing in long‐standing post‐polio patients on invasive home mechanical ventilation
Authors: Barle H. , Söderberg P. , Haegerstrand C. , Markström A.
Published: February 2005

Background:  Today, patients with chronic respiratory failure are commonly treated with non‐invasive bi‐level positive airway pressure ventilation, supporting spontaneous breathing. However, in conformity with previous clinical routine, many post‐polio patients with chronic respiratory failure are still treated with invasive (i.e. via a tracheostomy) controlled mechanical ventilation (CMV). The aim of the study was to investigate the effect of invasive bi‐level positive airway pressure ventilation on the work of breathing compared with that during the patients' ordinary CMV and spontaneous breathing without mechanical support.

Methods:  Nine post‐polio patients on invasive (tracheostomy) nocturnal CMV were investigated. Work of breathing was analysed by assessing differences in oxygen consumption (VO2) using indirect calorimetry. Hereby, the oxygen cost of breathing during the various ventilatory modes could be estimated and related to one another. Data on energy expenditure were also obtained.

Results:  The oxygen cost of breathing decreased by approximately 15% during bi‐level positive airway pressure ventilation compared with CMV and spontaneous breathing. There was no difference between predicted (Harris–Benedict equation) and measured energy expenditure.

Conclusion:  Invasive bi‐level positive airway pressure ventilation reduces the oxygen cost of breathing in long‐standing tracheostomized post‐polio patients, compared with CMV. Furthermore, the Harris–Benedict equation provides a reasonable prediction of energy expenditure in this group of patients.
Change in anaesthetic practice for Caesarean section in Germany
Authors: Stamer U. M. , Wiese R. , Stüber F. , Wulf H. , Meuser T.
Published: February 2005

Background:  Initial data from 1996 revealed that in contrast to several other countries general anaesthesia was the preferred anaesthetic technique for Caesarean section in Germany. However, anaesthetic practice for Caesarean section has changed during the last decades world‐wide. This investigation was performed to obtain more actual data on anaesthetic procedures in obstetric patients in German hospitals.

Methods:  Questionnaires on the practice of anaesthesia for Caesarean section were mailed to 918 German departments of anaesthesiology. Furthermore, the survey evaluated severe perioperative complications in obstetric patients.

Results:  The 397 completed replies in this survey represent 41.3% of all German deliveries in 2002. Spinal anaesthesia is now the most common technique (50.5%) for elective Caesarean section. In case of urgent and emergency Caesarean, delivery figures decrease to 34.6% and 4.8%, respectively. Epidural anaesthesia is performed in 21.6% of scheduled and 13.2% and 1.0% of non‐scheduled urgent or emergency Caesarean sections, respectively. Four maternal deaths and several non‐fatal episodes of gastric content aspiration were reported by the respondents.

Conclusions:  Compared to data obtained 6 years ago a significant increase in regional anaesthesia for Caesarean section has developed, with spinal anaesthesia being the preferred technique. Surveys can help to initiate discussion and improve current practice of anaesthetic care.
Anaesthetic practice for groin hernia repair – A nation‐wide study in Denmark 1998–2003
Authors: Kehlet H. , Nielsen M. Bay
Published: February 2005

Background:  Recent scientific data suggest that local infiltration anaesthesia for inguinal hernia surgery may be preferable compared to general anaesthesia and regional anaesthesia, since it is cheaper and with less urinary morbidity. Regional anaesthesia may have specific side‐effects and is without documented advantages on morbidity in this small operation.

Methods:  To describe the use of the three anaesthetic techniques for elective open groin hernia surgery in Denmark from January 1st 1998 to December 31st 2003, based on the Danish Hernia Database collaboration.

Results:  In a total of 57,505 elective open operations 63.6% were performed in general anaesthesia, 18.3% in regional anaesthesia and 18.1% in local anaesthesia. Regional anaesthesia was utilized with an increased rate in elderly and hospitalized patients. Outpatient surgery was most common with local infiltration anaesthesia.

Conclusion:  Use/choice of anaesthesia for groin hernia repair is not in accordance with recent scientific data. Use of spinal anaesthesia should be reduced and increased use of local anaesthesia is recommended to enhance recovery and reduce costs.
Reduction of opioid‐related adverse events using opioid‐sparing analgesia with COX‐2 inhibitors lacks documentation: A systematic review
Authors: Rømsing J. , Møiniche S. , Mathiesen O. , Dahl J. B.
Published: February 2005

Background:  We have reviewed opioid‐related adverse events in studies of opioid sparing with cyclooxygenase‐2 (COX‐2) inhibitors compared with placebo in postoperative pain.

Methods:  Randomized, controlled trials were evaluated. Outcome measures were significant reduction in consumption of supplementary opioids with the COX‐2 inhibitors and reported opioid‐related adverse events (nausea, vomiting, constipation, dizziness, sedation, pruritus and/or urinary retention) 0–24 h after surgery.

Results:  Nineteen studies including 26 comparisons of four COX‐2 inhibitors (rofecoxib, celecoxib, parecoxib and valdecoxib) were evaluated, in which significant opioid‐sparing averaging about 35% with COX‐2 inhibitors and opioid‐related adverse events were reported. The trials were in general of high quality (median Oxford quality score 4) but the reporting quality of adverse events was poor. Opioid‐related adverse events, i.e. vomiting, constipation and pruritus, were only significantly reduced with COX‐2 inhibitors in four of the 26 comparisons. Quantitative analysis of combined data revealed a significantly reduced risk for only dizziness; the clinical relevance was minor as the number needed to treat (NNT) was about 33.

Conclusion:  The limitation of this review is the lack of quality of data of adverse events from the original trials. Although supplementary opioid consumption in all trials was significantly reduced by on average 35% with the COX‐2 inhibitors, it was only sporadically possible to demonstrate a clinically important reduction in opioid‐related adverse events. Data did not support the common opinion that opioid‐sparing with COX‐2 inhibitors provides much clinical beneficial effect with respect to opioid‐related adverse events. Future studies have to increase the awareness and proper reporting of adverse events in the postoperative period.
Rapid evolutionary change in a secondary sexual character linked to climatic change
Authors: Møller A. P. , Szép T.
Published: February 2005

The ability of organisms to respond evolutionarily to rapid climatic change is poorly known. Secondary sexual characters show the potential for rapid evolutionary change, as evidenced by strong divergence among species and high evolvability. Here we show that the length of the outermost tail feathers of males of the socially monogamous barn swallowHirundo rustica, feathers that provide a mating advantage to males, has increased by more than 1 standard deviation during the period from 1984 to 2003. Barn swallows from the Danish population studied here migrate through the Iberian Peninsula to South Africa in fall, and return along the same route in spring. Environmental conditions on the spring staging grounds in Algeria, as indexed by the Normalized Difference Vegetation Index, predicted tail length and change in tail length across generations. However, conditions in the winter quarters and at the breeding grounds did not predict change in tail length. Environmental conditions in Algeria in spring showed a temporal deterioration during the study period, associated with a reduction in annual survival rate of male barn swallows. Phenotypic plasticity in tail length of males, estimated as the increase in tail length from the age of 1 to 2 years, decreased during the course of the study. Estimates of directional selection differentials for male tail length with respect to mating success, breeding date, fecundity, survival and total selection showed temporal variation, with the intensity of breeding date selection, survival selection and total selection declining during the study. Response to selection as estimated from the product of heritability and total selection was very similar to the observed temporal change in tail length. These findings provide evidence of rapid micro‐evolutionary change in a secondary sexual character during a very short time period, which is associated with a rapid change in environmental conditions.
Consequence of herbivory for the fitness cost of herbicide resistance: photosynthetic variation in the context of plant–herbivore interactions
Authors: Gassmann A. J. , Futuyma D. J.
Published: February 2005

The cost of adaptations may depend on environmental conditions. We consider how the fitness cost of resistance to the herbicide triazine in Amaranthus hybridus interacts with folivory from the beetle Disonycha glabrata. Triazine‐resistant (TR) genotypes suffer a fitness cost because of a pleiotropic reduction in the light reaction of photosynthesis, which in turn often leads to a reduction in photosynthetic rate. We found that the fitness cost of triazine resistance was 360% greater in the presence than absence of D. glabrata. This resulted from multiple phenotypic trade‐offs, with TR plants suffering greater herbivory and displaying a diminished tolerance of damage. Our work highlights the importance of incorporating appropriate ecological variation into the assessment of fitness trade‐offs. The results of this study also illustrate the potential for herbivores to impose selection on photosynthetic variation, and for variation in resource acquisition to obscure fitness costs.
Sex and immunity in the yellow dung fly Scathophaga stercoraria
Authors: Schwarzenbach G. A. , Hosken D. J. , Ward P. I.
Published: February 2005

The immune system is of increasing interest to evolutionary biologists. Immunity may trade‐off against other fitness components, with recent work suggesting reproduction in particular impinges on immune defence. There may also be sex differences in the immune system. Additionally, while life history traits typically have low heritability, little is known about additive genetic variance of immunity. An insect's major defence against multicellular pathogens is to encapsulate the invader. Phenoloxidase (PO) is a key enzyme in the cascade resulting in the melanized capsule, and is often used to estimate resistance to an immune insult. We examined the effects of copulation, egg laying, sex and age on PO in Scathophaga stercoraria. We also measured the heritability of PO activity. The sexes differed in haemolymph PO activity and PO was significantly affected by age, but not by copulation or egg laying. There was significant heritable variation for haemolymph PO.
Maternal genetic effects set the potential for evolution in a free‐living vertebrate population
Authors: Wilson A. J. , Coltman D. W. , Pemberton J. M. , Overall A. D. J. , Byrne K. A. , Kruuk L. E. B.
Published: February 2005

Heritable maternal effects have important consequences for the evolutionary dynamics of phenotypic traits under selection, but have only rarely been tested for or quantified in evolutionary studies. Here we estimate maternal effects on early‐life traits in a feral population of Soay sheep (Ovis aries) from St Kilda, Scotland. We then partition the maternal effects into genetic and environmental components to obtain the first direct estimates of maternal genetic effects in a free‐living population, and furthermore test for covariance between direct and maternal genetic effects. Using an animal model approach, direct heritabilities (h2) were low but maternal genetic effects (m2) represented a relatively large proportion of the total phenotypic variance for each trait (birth weightm2 = 0.119, birth datem2 = 0.197, natal litter sizem2 = 0.211). A negative correlation between direct and maternal genetic effects was estimated for each trait, but was only statistically significant for natal litter size (ram = −0.714). Total heritabilities (incorporating variance from heritable maternal effects and the direct‐maternal genetic covariance) were significant for birth weight and birth date but not for natal litter size. Inadequately specified models greatly overestimated additive genetic variance and hence directh2(by a factor of up to 6.45 in the case of birth date). We conclude that failure to model heritable maternal variance can result in over‐ or under‐estimation of the potential for traits to respond to selection, and advocate an increased effort to explicitly measure maternal genetic effects in evolutionary studies.
Rapid Miocene–Pliocene dispersal and evolution of Mediterranean rajid fauna as inferred by mitochondrial gene variation
Authors: Valsecchi E. , Pasolini P. , Bertozzi M. , Garoia F. , Ungaro N. , Vacchi M. , Sabelli B. , Tinti F.
Published: February 2005

Rajidae (colloquially known as skates and rays) experienced multiple and parallel adaptive radiations allowing high species diversity and great differences of species composition between regional faunas. Nevertheless, they show considerable conservation of bio‐ecological, morphological and reproductive traits. The evolutionary history and dispersal of North‐east Atlantic and Mediterranean rajid fauna were investigated throughout the sequence analysis of the control region and 16S rDNA mitochondrial genes. Molecular estimates of divergence times indicated recent origin and rapid dispersal of the present species. Compared with the ancient origin of the family (Late Cretaceous), the present species diversity arose in a relatively narrow time‐window (12 Myr) from Middle Miocene to Early Pleistocene, likely by speciation processes related to dramatic geological and climatic events in the Mediterranean. Nucleotide substitution rates and phylogenetic relationships indicated Mediterranean endemic skates derived from sister species with wider distribution during Late Pliocene–Pleistocene. Skate phylogeny and systematics obtained using mitochondrial gene variation were largely consistent with those based on morpho‐anatomical data.
Ecological components and evolution of selfing in the freshwater snail Galba truncatula
Authors: Trouve S. , Degen L. , Goudet J.
Published: February 2005

The reproductive assurance hypothesis emphasizes that self‐fertilization should evolve in species with reduced dispersal capability, low population size or experiencing recurrent bottlenecks. Our work investigates the ecological components of the habitats colonized by the snail, Galba truncatula, that may influence the evolution of selfing. Galba truncatula is a preferential selfer inhabiting freshwater habitats, which vary with respect to the degree of permanence. We considered with a population genetic approach the spatial and the temporal degree of isolation of populations of G. truncatula. We showed that patches at distances of only a few meters are highly structured. The effective population sizes appear quite low, in the order of 10 individuals or less. This study indicates that individuals of the species G. truncatula are likely to be alone in a site and have a low probability of finding a partner from a nearby site to reproduce. These results emphasize the advantage of selfing in this species.
Sex‐specific selective pressures on body mass in the greater white‐toothed shrew, Crocidura russula
Authors: Bouteiller‐Reuter C. , Perrin N.
Published: February 2005

The direction, intensity and shape of viability‐, sexual‐ and fecundity selection on body mass were investigated in a natural population of the greater white‐toothed shrew (Crocidura russula), combining parentage assignment through molecular techniques and mark–recapture data over several generations. A highly significant stabilizing viability selection was found in both sexes, presumably stemming from the constraints imposed by their insectivorous habits and high metabolic costs. Sexual selection, directional in both sexes, was twice as large in males than in females. Our results suggest that body mass matters in this context by facilitating the acquisition and defense of a breeding territory. No fecundity selection could be detected. The direction of sexual size dimorphism (SSD) was in agreement with the observed pattern of selective pressures: males were heavier than females, because of stronger sexual selection. SSD intensity, however, was low compared with other mammals, because of the low level of polygyny, the active role of females in territory defense and the intensity of stabilizing viability selection.
A new locus for resistance to brown planthopper identified in the indica rice variety DV85
Authors: Su C. C. , Wan J. , Zhai H. Q. , Wang C. M. , Sun L. H. , Yasui H. , Yoshimura A.
Published: February 2005

The brown planthopper (BPH) is one of the most destructive insect pests of rice. Resistant varieties have proved to be one of the most economic and effective measures for BPH management. In this study, an indica rice ‘DV85’ showed resistance to biotype 2 of BPH by bulked seedling test, and a recombinant inbred line (RIL) population derived from a cross between a susceptible rice ‘Kinmaze’ and ‘DV85’ was phenotyped to map genetic factors conferring BPH resistance in ‘DV85′. Composite interval mapping revealed that one quantitative trait locus (QTL) with a LOD score of 10.1 was detected between XNpb202 and C1172 on chromosome 11. This QTL was designated as Qbph11. Qbph11 explained 68.4% of the phenotypic variance of BPH resistance in this population. The allele from the resistant parent ‘DV85’ at Qbph11 reduced the damage caused by BPH feeding and would be very useful in breeding resistant rice varieties via marker‐assisted selection.
Analysis of genomic variability in transgenic sugarcane plants produced by Agrobacterium tumefaciens infection
Authors: Carmona E. R. , Arencibia A. D. , Lopez J. , Simpson J. , Vargas D. , Sala F.
Published: February 2005

Three transgenic sugarcane populations produced by Agrobacterium tumefaciens infection were analysed for the presence of genomic variability. Plants of the original cultivar, plants regenerated without transformation, as well as transformed and untransformed calli were used as control treatments. Amplified fragment length polymorphism (AFLP) of DNA extracted from leaves or calli assessed genomic profiling. The average DNA polymorphism within each population was determined by calculating the polymorphism index, while the extent of genomic dissimilarity among individual plants within transgenic populations was verified in unweighted pair group method using arithmetic averages dendrograms. The results showed that the production of transgenic sugarcane plants by A. tumefaciens infection is accompanied by limited but detectable genomic changes and that, on average, these occur at the same rate in plant populations carrying different transgenes. Main factors contributing to somaclonal variation in transgenic sugarcane plants have been verified by pre‐existing DNA polymorphism into the donor genotype and in vitro culture steps during the transformation procedure. The relevant practical conclusion from this finding is that the AFLP analysis may be effectively used to identify individual transgenic plants with the least genomic deviation from the parental ones. The selected genotype would be conserved as cultivated sugarcane is asexually propagated.
Resynthesis of Brassica napus L. for self‐incompatibility: self‐incompatibility reaction, inheritance and breeding potential
Authors: Rahman M. H.
Published: February 2005

Self‐incompatibility (SI) in Brassica has been considered as a pollination control mechanism for commercial hybrid seed production, and so far has been extensively used in vegetable types of Brassicas. Oilseed rape Brassica napus (AACC) is naturally self‐compatible in contrast to its parental species that are generally self‐incompatible. Introduction of S‐alleles from its parental species into oilseed rape is therefore needed to use this pollination control mechanism in commercial hybrid seed production. Self‐incompatible lines of B. napus, carrying SI alleles in both A and C genomes, were resynthesized from self‐incompatible B. oleracea var. italica (CC) cv.‘Green Duke’ and self‐incompatible B. rapa ssp. oleifera (AA) cv. ‘Horizon’, ‘Colt’ and ‘AC Parkland’. All resynthesized B. napus lines exhibited strong dominant SI phenotype. Reciprocal cross‐compatibility was found between some of these self‐incompatible lines. The inheritance of S‐alleles in these resynthesized B. napus was digenic confirming that each of the parental genomes contributed one S‐locus in the resynthesized B. napus lines. However, the presence of two S‐loci in the two genomes was found not to be essential for imparting a strong SI phenotype. Possible use of these dominant self‐incompatible resynthesized B. napus lines in hybrid breeding is discussed.
Inheritance and mapping of a restorer gene for the rapeseed cytoplasmic male sterile line 681A
Authors: Liu Z. , Guan C. , Zhao F. , Chen S.
Published: February 2005

A novel cytoplasmic male sterility‐fertility restoration system has been developed in rapeseed (Brassica napus). The cytoplasmic male sterile line 681A was derived from a spontaneous male sterile mutant in a newly released double‐low rapeseed cultivar ‘Xiangyou 13′. The restorer line 714R was identified in the interspecific progeny from a B. napus×B. juncea‐cross. Genetic analysis showed that fertility restoration for 681A cytoplasmic male sterility was controlled by a single dominant nuclear gene which might originate from B. juncea. The RAPD marker S1039‐520 was found to be linked to the restorer gene in F2 progeny of 681A × 714R with a recombination frequency of 5.45%.
Identification and inheritance of a partially dominant gene for yellow seed colour in Brassica napus
Authors: Liu X. P. , Tu J. X. , Chen B. Y. , Fu T. D.
Published: February 2005

A yellow‐seeded doubled haploid (DH) line no. 2127‐17, derived from a resynthesized Brassica napus L., was crossed with two black‐seeded Brassica cultivars ‘Quantum’ and ‘Sprint’ of spring type. The inheritance of seed colour was investigated in the F2, and BC1 populations of the two crosses and also in the DH population derived from the F1 of the cross ‘Quantum’× no. 2127‐17. Seed colour analysis was performed with the colorimeter CR‐300 (Minolta, Japan) together with a visual classification system. The immediate F1 seeds of the reciprocals in the two crosses had the same colour as the self‐pollinated seeds of the respective black‐ and yellow‐seeded female parents, indicating the maternal control of seed colour. The F1 plants produced yellow‐brown seeds that were darker in colour than the seeds of no. 2127‐17, indicating the partial dominance of yellow seed over black. In the segregating BC1 progenies of the two crosses, the frequencies of the black‐ and yellow‐seeded plants fit well with a 1 : 1 ratio. In the cross with ‘Quantum’, the frequencies of yellow‐seeded and black‐seeded plants fit with a 13 : 3 ratio in the F2 progeny, and with a 3 : 1 ratio in the DH progeny. However, a 49 : 15 segregation ratio was observed for the yellow‐seeded and black‐seeded plants in the F2 progeny of the cross with ‘Sprint’. It was postulated from these results that seed colour was controlled by three pairs of genes. A dominant yellow‐seeded gene (Y) was identified in no. 2127‐17 that had epistatic effects on the two independent dominant black‐seeded genes (B and C), thereby inhibiting the biosynthesis of seed coat pigments.
Evaluation of resistance to sharka (Plum pox virus) of several Prunus rootstocks
Authors: Rubio M. , Martínez‐Gómez P. , Pinochet J. , Dicenta F.
Published: February 2005

Sharka (Plum pox virus, PPV) severely affects the production of most Prunus species in the areas affected by the disease. In this study, the resistance of 15 Prunus rootstocks to a Dideron type isolate of PPV was evaluated under controlled conditions in an insect‐proof greenhouse. After four cycles of study,‘GF677’ almond x peach hybrid,‘Myrobolan 29C plum and ‘L2’ cherry did not show any symptoms and were ELISA‐DASI and RT‐PCR negative. These were considered resistant to PPV. The rest of the rootstocks assayed showed symptoms of sharka (confirmed by ELISA‐DASI or RT‐PCR), although the level of susceptibility was different for each rootstock.‘GF305’ peach, ‘Puebla de Soto’ plum and ‘Real Fino’ apricot, were highly susceptible to PPV, showing strong sharka symptoms and being ELISA and RT‐PCR positive. ‘Marianna 2624’ plum,‘AC 9921‐07’ hybrid and ‘CP‐2’ plum showed susceptibility to PPV confirmed by ELISA‐DASI and RT‐PCR positives.‘Nemaguard’ and ‘Nemared’ hybrids, ‘Torinel’ plum and ‘STN2’ hybrid showed an intermediate susceptibility to PPV with slight sharka symptoms and were ELISA‐DASI and RT‐PCR positive. Whereas, ‘Montclar’ peach and ‘Evrica’ hybrid showed moderate resistance to PPV with slight sharka symptoms and were ELISA positive but RT‐PCR negative. The results open new possibilities in the search for different sources of resistance to PPV within Prunus.
QTL analysis of important pith characteristics in a cross between two inbred lines of chicory (Cichorium intybus var. foliosum): a preliminary study
Authors: Van Stallen N. , Vandenbussche B. , Londers E. , Noten V. , De Proft M.
Published: February 2005

The genetic basis of pith characteristics in chicory (Cichorium intybus L. var. foliosum Hegi) was investigated. Quantitative trait loci (QTL) were mapped in an F2 population (565 F2 plants) derived from a cross between two inbred chicory lines. A molecular marker linkage map of this cross had previously been constructed based on 129 random amplified polymorphic DNA markers. Each F2 plant was selfed and plant characteristics were measured in the F3 populations. Although variation in pith characteristics was largely environmentally influenced, QTL for the characteristics length of pith, browning of the pith, hollow pith and apple pith were detected in many linkage groups. Interactions between QTL were found for the three characteristics: pith length, browning of the pith and hollow pith. The QTL detected confirmed the early forcing suitability of the one parent inbred line and late forcing suitability of the other.
Germinable soil seed banks in a tropical savanna: seasonal dynamics and effects of fire.
Authors: Williams Paul R. , Congdon Robert A. , Grice Anthony C. , Clarke Peter J.
Published: February 2005

Abstract  The germinable soil seed bank of a tropical eucalypt savanna of north‐eastern Australia was found to be dominated by grasses and forbs, with seed bank density ranging from 58 to 792 seeds per square metre, from a total of 53 species. Late dry season fires and the fire‐related cues, heat shock and smoke, broke the seed dormancy of a range of tropical savanna species. Heat shock promoted the germination of the species groups natives, exotics, subshrubs, ephemeral and twining perennial forbs, and the common species Indigofera hirsuta, Pycnospora lutescens and Triumfetta rhomboidea. Exposure to smoke at ambient temperature promoted germination from the soil seed bank of the species groups combined natives, upright perennial forbs and grasses, as well as the common grasses Digitaria breviglumis and Heteropogon triticeus. The germinable soil seed bank varied seasonally, increasing from the mid wet season (February) and early dry season (May) to a maximum in the late dry season (October). The effect of recent fire history on soil seed bank dynamics was limited to the immediate release of some seed from dormancy; a reduction in seed densities of subshrubs and monocots, other than grasses, in recently burnt savanna; and enhanced seed density of the ephemeral I. hirsuta in the year following fire. The seed banks of most savanna species were replenished in the year following burning.
Estimating abundance and spatial distribution patterns of the bubble crab Dotilla fenestrata (Crustacea: Brachyura)
Authors: Flores Augusto A. V. , Abrantes Katya G. , Paula José
Published: February 2005

Abstract  The bubble crab Dotilla fenestrata forms very dense populations on the sand flats of the eastern coast of Inhaca Island, Mozambique, making it an interesting biological model to examine spatial distribution patterns and test the relative efficiency of common sampling methods. Due to its apparent ecological importance within the sandy intertidal community, understanding the factors ruling the dynamics of Dotilla populations is also a key issue. In this study, different techniques of estimating crab density are described, and the trends of spatial distribution of the different population categories are shown. The studied populations are arranged in discrete patches located at the well‐drained crests of nearly parallel mega sand ripples. For a given sample size, there was an obvious gain in precision by using a stratified random sampling technique, considering discrete patches as strata, compared to the simple random design. Density average and variance differed considerably among patches since juveniles and ovigerous females were found clumped, with higher densities at the lower and upper shore levels, respectively. Burrow counting was found to be an adequate method for large‐scale sampling, although consistently underestimating actual crab density by nearly half. Regression analyses suggested that crabs smaller than 2.9 mm carapace width tend to be undetected in visual burrow counts. A visual survey of sampling plots over several patches of a large Dotilla population showed that crab density varied in an interesting oscillating pattern, apparently following the topography of the sand flat. Patches extending to the lower shore contained higher densities than those mostly covering the higher shore. Within‐patch density variability also pointed to the same trend, but the density increment towards the lowest shore level varied greatly among the patches compared.
Fungal endophyte infection changes growth attributes inLolium multiflorumLam
Authors: Vila‐Aiub Martin M. , Gundel Pedro E. , Ghersa Claudio M.
Published: February 2005

Abstract Lolium multiflorumis a successful invader of postagricultural succession in the Inland Pampa grasslands in Argentina, becoming a dominant species in the plant community. Individual plants of this annual species are naturally highly infected with fungal endophytes (Neotyphodiumsp.) from early successional stages. We assessed the effect ofNeotyphodiuminfection on the biology ofL. multiflorum. We evaluated growth attributes between endophyte infected (E+) and uninfected (E–) plants under non‐competitive conditions during the normal growing season. E+ plants produced significantly more vegetative tillers and allocated more biomass to roots and seeds. Although seed germination rates were greater in endophyte free plants, the rate of emergence and the final proportion of emerged seedlings were similar between the biotypes. The greater production of vegetative tillers, and the greater resource allocation to roots and seeds are likely to confer an ecological advantage to E+ plants, thus enabling their dominance over the E– individuals in natural grasslands.
Food web structure in a tropical stream ecosystem
Authors: Motta Rosinês L. , Uieda Virginia S.
Published: February 2005

Abstract  This study investigated the structure and properties of a tropical stream food web in a small spatial scale, characterizing its planktonic, epiphytic and benthic compartments. The study was carried out in the Potreirinho Creek, a second‐order stream located in the south‐east of Brazil. Some attributes of the three subwebs and of the conglomerate food web, composed by the trophic links of the three compartments plus the fish species, were determined. Among compartments, the food webs showed considerable variation in structure. The epiphytic food web was consistently more complex than the planktonic and benthic webs. The values of number of species, number of links and maximum food chain length were significantly higher in the epiphytic compartment than in the other two. Otherwise, the connectance was significantly lower in epiphyton. The significant differences of most food web parameters were determined by the increase in the number of trophic species, represented mainly by basal and intermediate species. High species richness, detritus‐based system and high degree of omnivory characterized the stream food web studied. The aquatic macrophytes probably provide a substratum more stable and structurally complex than the sediment. We suggest that the greater species richness and trophic complexity in the epiphytic subweb might be due to the higher degree of habitat complexity supported by macrophyte substrate. Despite differences observed in the structure of the three subwebs, they are highly connected by trophic interactions, mainly by fishes. The high degree of fish omnivory associated with their movements at different spatial scales suggests that these animals have a significant role in the food web dynamic of Potreirinho Creek. This interface between macrophytes and the interconnections resultant from fish foraging, diluted the compartmentalization of the Potreirinho food web.
QT dispersion in type 2 diabetic patients with altered diurnal blood pressure rhythm
Authors: Deyneli O. , Ersöz H. Ö. , Yavuz D. , Fak A. S. , Akalin S.
Published: February 2005

Background:  QT dispersion (QTd) is a good prognostic marker in type 2 diabetic patients without previous cardiovascular disease. Diabetic patients with an attenuated decline in nocturnal blood pressure (non‐dippers) have been shown to have increased risk of diabetic complications, vascular events and mortality.

Aim:  The aim of this study was to evaluate the relationship between diurnal blood pressure rhythm, QTd and microvascular complications in type 2 diabetic patients.

Methods:  Cardiovascular autonomic function tests, 24‐h ambulatory blood pressure monitoring and urinary albumin excretion measurements were performed in healthy controls (n = 25), normoalbuminuric (n = 34) and microalbuminuric (n = 23) type 2 diabetic patients. QTd was assessed manually from 12‐lead surface electrocardiograms.

Results:  Compared with the controls, both normoalbuminuric and microalbuminuric diabetic patients had increased QTd (59.11 ± 15.86; 60.27 ± 17.95 vs. 40.48 ± 10.92, p < 0.001 and p < 0.001, respectively). Similarly, diabetic patients had increased QTd regardless of the presence of autonomic neuropathy. On the other hand, non‐dipper diabetic patients had increased QTd compared with the controls and dipper diabetic patients (69.73 ± 14.50 vs. 40.48 ± 10.92; 47.84 ± 9.62 ms, p < 0.001). There was a negative correlation between QTd and diurnal diastolic blood pressure change (r = −0.48, p < 0.0005).

Conclusion:  Patients with type 2 diabetes mellitus were found to have increased QT dispersion irrespective of the presence of diabetic autonomic neuropathy. However, QT dispersion in dipper diabetic patients was similar to the controls. This finding might point out that attenuated decline of nocturnal blood pressure could be a more sensitive marker for autonomic neuropathy.
Inverse relationship between cord blood adiponectin concentrations and the number of cigarettes smoked during pregnancy
Authors: Pardo I. M. C. G. , Geloneze B. , Tambascia M. A. , Barros A. A.
Published: February 2005

Background:  Maternal smoking is linked with several neonatal metabolic disorders. Adiponectin is an adipose‐specific hormone with anti‐inflammatory and antiatherogenic properties.

Aim:  The aim of this study was to evaluate the effect of maternal smoking on cord blood adiponectin concentrations.

Methods:  We evaluate the effect of maternal smoking on cord blood adiponectin concentrations comparing 14 full‐term and seven preterm newborns born to mothers who smoked during pregnancy with 77 full‐term and 10 preterm neonates born to non‐smokers mothers.

Results:  Maternal smoking during pregnancy was significantly associated with decreased adiponectin levels of preterm newborns (p < 0.05).

Conclusions:  Our findings also reveal a significant relationship between the reported number of cigarettes smoked during pregnancy and cord blood adiponectin concentrations (p = 0.01), suggesting that this association could have a causal relationship.
An algorithm for the treatment of type 2 diabetes in Latin America
Authors: Chacra A. R. , Davidson J. A. , Diaz J. , Escalante‐Pulido M. , Litwak L. E. , Mestman J. H. , More L. , Violante R. M.
Published: February 2005

Summary:  Diabetes is a principal and growing health concern in Latin America, accounting for significant mortality and morbidities. Large, randomized, prospective trials of various interventional therapies in patients with both type 1 and type 2 diabetes have demonstrated that reductions in hyperglycaemia and management of diabetes‐related risk factors can significantly reduce the micro‐ and macrovascular complications of diabetes. Therefore, patients with type 2 diabetes will benefit from more aggressive treatment regimens to help decrease the occurrence and rate of progression of diabetic complications. Given the many complexities of diabetes management, it is often difficult for general practice physicians to stay abreast of emerging treatment strategies and therapies. Owing to the high prevalence of type 2 diabetes in Latin America, the majority of patients with diabetes are treated by generalists rather than specialists. This article was intended to assist physicians and other healthcare professionals in developing and using effective treatment strategies to stem the growing epidemic of diabetes and its complications in Latin America.
Comparison of pioglitazone with other antidiabetic drugs for associated incidence of liver failure: no evidence of increased risk of liver failure with pioglitazone
Authors: Rajagopalan R. , Iyer S. , Perez A.
Published: February 2005

Aim:  The aim of this study was to assess the incidence of liver failure in association with antidiabetic treatment using pioglitazone vs. other oral antidiabetic medications.

Methods:  The study was a retrospective analysis of claim data from the PharMetrics Patient‐Centric Database that had over 1.12 million enrollees with type 2 diabetes. All patients, ≥18 years of age with type 2 diabetes, who had initiated treatment either with a thiazolidinedione (pioglitazone and rosiglitazone), sulfonylurea or metformin were identified and matched on the basis of propensity scores, which served as a proxy for severity of disease. The primary measure of interest was the incidence of liver failure or hepatitis post‐index date. In addition to unadjusted comparisons, Cox proportional hazard models were employed to estimate the risk of developing liver failure or hepatitis.

Results:  There was no significant difference in the 1‐ and 2‐year incidence rates of liver failure or hepatitis (primary and secondary diagnoses) between the pioglitazone monotherapy group and the respective comparator groups. In Cox proportional hazard models controlling for age, pre‐index total healthcare costs, Charlson comorbidity index, procedures and a hospitalization or Emergency room (ER) visit for pre‐index hyperglycaemia, and pioglitazone were not associated with an increased risk of liver failure or hepatitis, compared to all other defined groups. Furthermore, no primary or secondary diagnosis of liver failure was reported in the pioglitazone group during the follow‐up period.

Conclusions:  Results of retrospective data analysis demonstrate no evidence of increased risk of liver failure or hepatitis for patients initiating therapy on pioglitazone, compared to other oral antidiabetic agents. Pioglitazone therapy was not associated with an increased risk of liver failure at 2 years relative to other oral antidiabetic therapies.
Effects of metformin on the body composition in subjects with risk factors for type 2 diabetes
Authors: Rodríguez‐Moctezuma J. R. , Robles‐López G. , López‐Carmona J. M. , Gutiérrez‐Rosas M. J.
Published: February 2005

Objectives:  To measure the effect of metformin on the body composition, insulin resistance and sensitivity in subjects with risk factors for type 2 diabetes mellitus (type 2 DM).

Design:  Placebo‐controlled clinical trial.

Material and methods:  Twenty‐three subjects with risk factors for type 2 DM were randomly assigned to receive 850 mg of metformin or a placebo twice a day for 2 months. Before and after the treatment, the body mass index and waist/hip ratio were calculated, the body composition was measured through bioelectric impedance and the fasting levels of blood glucose, insulin, triglycerides and cholesterol were measured. The level of insulin resistance was calculated by the homeostatic model and the level of sensitivity by the quantitative insulin sensitivity check index method. The Wilcoxon rank test was used.

Results:  Twenty‐one subjects completed the study, 12 of the metformin group and nine of the placebo group. In the metformin group, there was a decrease in fat weight from 25.9 ± 9.4 to 20.8 ± 9.2 kg, p < 0.01, an increase in lean weight from 57.05 ± 13.6 to 61.9 ± 16.5 kg, p < 0.01, an increase in basal metabolism from 1735 ± 413 to 1878 ± 505 calories/day, p < 0.05 and an increase in body water, p < 0.05. There was no significant decrease in insulin resistance. In the placebo group, the blood glucose increased from 84.7 ± 13 to 96.7 ± 16 mg/dl, p < 0.05. There were no significant modifications in lipids.

Conclusions:  The administration of metformin for 2 months improves the parameters of body composition and insulin dynamics in subjects with risk factors for type 2 DM.
Effects of a novel formulation of essential oils on glucose– insulin metabolism in diabetic and hypertensive rats: a pilot study
Authors: Talpur N. , Echard B. , Ingram C. , Bagchi D. , Preuss H.
Published: February 2005

Background:  Insulin resistance and its most severe form type 2 diabetes mellitus are rapidly increasing throughout the world. It is generally recognized that natural products with a long history of safety can increase insulin sensitivity.

Aims:  The present investigation examined the ability of various combinations of essential oils such as fenugreek, cinnamon, cumin, oregano, etc. to enhance insulin sensitivity. As a first approximation, we examined the effects of these natural products on Zucker fatty rats (ZFRs), a model of obesity and insulin resistance, and spontaneously hypertensive rats (SHRs), a model of genetic hypertension.

Material and Methods:  Water or essential oils were given orally via droplets, and insulin sensitivity was estimated by systolic blood pressure (SBP) changes and circulating glucose and/or insulin concentrations.

Results:  We have found that the ability to alter SBP in rat models is the most sensitive early index of insulin sensitivity. The combined essential oils lowered circulating glucose levels and SBP in both ZFRs and SHRs, suggesting that these natural products are enhancing insulin sensitivity. The second series of studies examined two additional combinations of essential oils along with the original formula. The major differences were in the types and proportions of individual oils contributing to a given formula.

Conclusions:  Although all the three formulae decreased SBP in ZFRs, one of the formulae was more effective than the others in lowering circulating glucose in the glucose tolerance testing. Accordingly, some essential oils may be added to the long list of natural products that can affect insulin sensitivity.
Genetics of type 2 diabetes mellitus: status and perspectives
Authors: Hansen Lars , Pedersen Oluf
Published: February 2005

Throughout the last decade, molecular genetic studies of non‐autoimmune diabetes mellitus have contributed significantly to our present understanding of this disease's complex aetiopathogenesis. Monogenic forms of diabetes (maturity‐onset diabetes of the young, MODY) have been identified and classified into MODY1–6 according to the mutated genes that by being expressed in the pancreatic β‐cells confirm at the molecular level the clinical presentation of MODY as a predominantly insulin secretory deficient form of diabetes mellitus. Genomewide linkage studies of presumed polygenic type 2 diabetic populations indicate that loci on chromosomes 1q, 5q, 8p, 10q, 12q and 20q contain susceptibility genes. Yet, so far, the only susceptibility gene, calpain‐10 (CAPN10), which has been identified using genomewide linkage studies, is located on chromosome 2q37. Mutation analyses of selected ‘candidate’ susceptibility genes in various populations have also identified the widespread Pro12Ala variant of the peroxisome proliferator‐activated receptor‐γ and the common Glu23Lys variant of the ATP‐sensitive potassium channel, Kir6.2 (KCNJ11). These variants may contribute significantly to the risk type 2 diabetes conferring insulin resistance of liver, muscle and fat (Pro12Ala) and a relative insulin secretory deficiency (Glu23Lys). It is likely that, in the near future, the recent more detailed knowledge of the human genome and insights into its haploblocks together with the developments of high‐throughput and cheap genotyping will facilitate the discovery of many more type 2 diabetes gene variants in study materials, which are statistically powered and phenotypically well characterized. The results of these efforts are likely to be the platform for major progress in the development of personalized antidiabetic drugs with higher efficacy and few side effects.