bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence of Venous Obstruction in Permanent Endovenous Pacing in Newborns and Infants: Follow‐Up Study
Authors: STOJANOV PETAR , VRANES MILE , VELIMIROVIC DUSAN , ZIVKOVIC MIRJANA , KOCICA MLADEN J. , DAVIDOVIC LAZAR , NESKOVIC VOISLAVA , STAJEVIC MILA 
Published: May 2005

Objective: We examined the prevalence of venous obstruction in 12 newborns and infants with permanent endovenous ventricular pacing, clinically, and by ultrasonographic assessment of hemodynamics (spontaneity, phasicity, velocity, and turbulence of flow) and morphologic parameters (compressibility, wall thickness, and thrombus presence).
Material and Methods: All implantations of single ventricular unipolar endovenous steroid leads, were performed via cephalic vein, and pacemakers were placed in subcutaneous pocket in right prepectoral region. After the vascular surgeon has carefully examined all children for presence of venous collaterals in the chest wall, morphologic and hemodynamic parameters of the subclavian, axillary, and internal jugular veins, were assessed by linear‐array color Doppler. Lead capacity (LC) was calculated for each patient.
Results: Mean age of patients at implant was 6.2 months (range 1 day–12 months), mean weight 6.5 kg (range 2.25–10 kg), and mean height 60.9 cm (range 48–78 cm). Mean LC was 1.99 (range 1.14–3.07). Total follow‐up was 1023 and mean follow‐up 85.2 pacing months (range 3–156). No clinical signs of venous obstruction were observed. Mild stenosis (20%) of subclavian vein was found by color Doppler in 2/12 patients. Both had adequate lead diameter for body surface.
Conclusion: Permanent endovenous pacing is a feasible procedure, even in children of body weight less than 10 kg, with quite acceptable impact on venous system patency.
Optimal Side of Implant for Single‐Lead VDD Pacing: Right‐Sided Versus Left‐Sided Implantation
Authors: HAGHJOO MAJID , ARYA ARASH , EMKANJOO ZAHRA , SADR‐AMELI MOHAMMAD ALI 
Published: May 2005

Background: Atrial undersensing occurs in a considerable number of patients with single‐lead VDD pacing. This study tried to determine the role of implant side in maintenance of the VDD mode in patients with isolated atrioventricular (AV) block.
Methods: Eighty‐two patients with isolated AV block (46 females; mean age, 58 ± 17 years) received a single‐lead VDD pacemaker (Medtronic Kappa, n = 70 and St. Jude Medical Affinity, n = 12). The patients were randomly assigned to one of two implantation groups (group I: right‐sided VDD and group II: left‐sided VDD). In each group, the P‐wave amplitudes were determined at implantation, predischarge, 2‐month, and 6‐month follow‐up. At each follow‐up visit, stored event histograms of pacemaker were also retrieved. The atrial sensing measurements were compared between two groups.
Results: Implantation was easier from right side (1.7 ± 1.0 vs 2.8 ± 1.7 attempts, P = 0.001). Implant P‐wave was higher in group I compared to group II (4.2 ± 1.7 vs 2.7 ± 1.0 mV, P < 0.0001). During follow‐up, higher P‐wave amplitudes were obtained in group I both at predischarge (2.6 ± 1.3 vs 1.4 ± 1.1 mV, P < 0.0001), 2‐month (2.8 ± 1.8 vs 1.3 ± 1.0 mV, P < 0.0001), and 6‐month (2.9 ± 1.7 vs 1.3 ± 0.9 mV, P < 0.0001) evaluations but remained stable throughout the 6 months in both groups. After implantation, VDD function was better maintained in group I than group II (100% vs 90%, P = 0.026). Incidence of atrial undersensing was lower in group I than group II (P = 0.026) in last follow‐up visit.
Conclusions: Implant side has a significant influence on atrial sensing performance in single‐lead VDD pacing. Thus, right‐side implantation should be the preferred approach for the implantation of VDD single‐lead systems.
Effect of IKr Blocker Nifekalant on Atrial Action Potential Duration After Successful Internal Cardioversion of Chronic Atrial Fibrillation
Authors: KOFUNE TATSUYA , WATANABE ICHIRO , OKUBO KIMIE , OKUMURA YASUO , MASAKI RIKO , SHINDO ATSUSHI , SAITO SATOSHI 
Published: May 2005

Background: Chronic atrial fibrillation (AF) is characterized by a marked decrease in the atrial effective refractory period (ERP) and in the ERP adaptation to rate as well as a decrease in the atrial conduction velocity. Little information is available about the ionic mechanisms underlying AF in humans.
Materials and Methods: We studied the effect of IKr blocker nifekalant on the rate‐dependent changes in atrial action potential duration in 11 patients after successful internal cardioversion of chronic AF of >2 months duration and in 7 patients without AF. In AF patients, right atrial (RA) monophasic action potential (MAP) was recorded at pacing cycle lengths (CLs) of 800–250 ms before and after administration of nifekalant. In control patients, RAMAP was recorded at CLs of 600 and 350 ms before and after administration of nifekalant.
Results: Nifekalant significantly increased RAMAPD at 90% repolarization (RAMAPD90) at CLs of 800–300 ms in the AF patients. The increase in RAMAPD90 by nifekalant became significantly smaller at shorter CLs (42.5 ± 12.4 ms at a CL of 600 ms vs 32.8 ± 14.5 ms at a CL of 350 ms, P < 0.05). Effect of nifekalant on RAPMAPD was attenuated at CL of 600 ms in AF patients in comparison to control patients (increase in RAMAPD in control; 73.0 ± 36.6 ms vs increase in RAMAPD in AF; 42.5 ± 12.4 ms, P < 0.05); however, it was similar at a CL of 350 ms between control and AF patients.
Conclusions: Electrophysiological effects of nifekalant are significantly attenuated in the chronically remodeled human atrium at slower heart rates, but the beneficial effect of RAMAPD prolongation by IKr blocker was well‐preserved even at shorter CLs after chronic AF.
Reduced fitness of the leafhopper vector Scaphoideus titanus exposed to Flavescence dorée phytoplasma
Authors: Bressan Alberto , Girolami Vincenzo , Boudon‐Padieu Elisabeth 
Published: May 2005

Abstract Scaphoideus titanus Ball (Homoptera: Cicadellidae), a specialist and univoltine leafhopper on grapevine (Vitis vinifera L.) (Vitaceae), is a vector of Flavescence dorée phytoplasma (FDP) in vineyards of European temperate areas. Males and females of the leafhopper were exposed to FDP by feeding on infected broad bean (Vicia faba L.) (Fabaceae). Detection of FDP by the amplification of phytoplasma DNA with polymerase chain reaction assays of individual insects revealed an acquisition rate of 91.4% (96/105) after an acquisition access period of 13 days. The adult life span of FD‐exposed males and females was much less than that of leafhoppers fed on healthy broad bean, as revealed by ANOVA on the quartiles of survival distribution and Weibull scale parameter. The progeny of exposed females (number of nymphs emerging from eggs deposited on woody cane segments) was significantly less than the progeny of unexposed females. Eggs produced by FD‐exposed females were slightly but significantly delayed in hatching. Reduced fecundity was confirmed by dissecting FD‐exposed and non‐exposed 42‐day‐old females and counting the number of fully sized eggs in each leafhopper. There was no evidence of transovarial passage of FDP in the offspring of infected females after 72 nymphs were reared on a healthy grapevine until the fifth instar or adult appearance and then confined on broad bean seedlings.
Plant quality, progeny sequence, and the sex ratio of the sycamore aphid, Drepanosiphum platanoidis
Authors: Leather S.R. , Wade F.A. , Godfray H.C.J. 
Published: May 2005

AbstractThe reproductive sequence of sexuparae of the sycamore aphid, Drepanosiphum platanoidis (Schrank) (Homoptera: Callaphididae), observed in the field and glasshouse was examined to elucidate the relationship between host nutrition and sex ratio. The observations were made in autumn when the transition from parthenogenetic to sexual reproduction occurred. A switch occurred in the reproductive sequence of the sexuparae. The production of apterous sexual females (oviparae) was followed by alate males, after a brief reproductive pause lasting 2.5–4.0 days. The switchover period was relatively constant across treatments and years. On poor hosts, the first appearance of the oviparae was a day later, whereas the first appearance of males was a day earlier than those on good nutrition. The primary sex ratio (i.e., proportion of males) was numerically female biased. Under semi‐natural field conditions it was 0.22, but altered to 0.18 and 0.29, respectively, under poor and good host nutrition in the glasshouse. In both the field and glasshouse, nymphal development time was significantly longer in oviparae (ca. 22 days) than in males (ca. 18 days). The time from birth to adult was significantly shorter on good hosts (oviparae: 20 days; males: 17 days) than on poor hosts (oviparae: 23 days; males: 19 days). The proportion of nymphs surviving to the adult moult was not dependent on sex in both the field and glasshouse, but the chances of survival were slightly enhanced under good (88%) compared with poor (82%) host nutritive status. In conclusion, the order of morph production and differences in maturation times ensured the synchronisation of the sexes so that mating and oviposition opportunities were optimised before the onset of winter. The female‐bias in the sex ratio maximised the fitness of sexuparae, and reduced the chances of local mate competition by economising in members of the competing sex.
Sexual dimorphism and the impact of temperature on the pupal and adult stages of Sepedon spinipes spinipes, a potential biological control agent of fascioliasis
Authors: McDonnell R. J. , Mulkeen C. J. , Gormally M. J. 
Published: May 2005

AbstractThe malacophagous feeding behaviour of larvae of members of the family Sciomyzidae makes the group ideal for the selection of potential biological control agents of snail hosts of trematode diseases. The aim of this study was to investigate the effects of temperature (14 °C, 17 °C, 20 °C, 23 °C, and 26 °C) on the pupal and adult stages of Sepedon spinipes spinipes (Scopoli) (Diptera: Sciomyzidae). Larval prey density effects on the pupal stage and the extent of sexual dimorphism within the species are also assessed. Optimum growth conditions for the pupal stage and pre‐oviposition/oviposition periods, and female fecundity are identified for mass culturing purposes. The tendency of mature third instar larvae to engage in wandering behaviour is highlighted, and the biological control implications of such behaviour are discussed. Female puparia were significantly (P<0.001) heavier than males for both larval prey densities. Such sexual dimorphism would enable the prediction of adult sex from puparial weight prior to eclosion, thereby facilitating culture establishment. The effect of three food types [honey/yeast mixture only, crushed Radix balthica (L.) (Gastropoda: Pulmonata: Lymnaeidae) only, and honey/yeast mixture plus a crushed snail] on adult longevity (laboratory conditions) was also determined and the results suggest that adults live longest when provided with a crushed snail and a honey/yeast mixture.
Extended life cycle in the chestnut weevil: prolonged or repeated diapause?
Authors: Soula Bertrand , Menu Frédéric 
Published: May 2005

AbstractMany insect species extend the life cycle of a part of their population over several years. The adaptive value of these long cycles is now well documented, but the physiological processes underlying them have been little studied. Long life cycles are usually viewed as resulting from prolonged diapause proceeding from a simple extension of the usual winter diapause. However, this hypothesis has not been greatly tested, and information is lacking for species with a larval diapause. The energetic cost of a prolonged larval diapause also needs to be measured, because the few published estimates of lipid consumption concern an imaginal diapause. It is not therefore clear whether the negligible lipid consumption observed during adult prolonged diapause can be extrapolated to larval diapause. From microrespirometry and lipid measures in the chestnut weevil, Curculio elephas Gyllenhal (Coleoptera: Curculionidae), we show that: (1) in contrast to the usual hypothesis, the long cycle does not result from an extension of larval winter diapause, but is due to a prolonged diapause occurring secondarily to a developmental phase, and (2) energy consumption during the prolonged diapause is not negligible, but is provided for by a higher initial lipid content in the long cycle individuals. The adaptive value of the observed cycle is discussed.
Potential Uptake of
Escherichia coli
O157:H7 from Organic Manure into Crisphead Lettuce
Authors: Johannessen Gro S. , Bengtsson Gunnar B. , Heier Berit T. , Bredholt Sylvia , Wasteson Yngvild , Rørvik Liv Marit 
Published: May 2005

ABSTRACT

To investigate the potential transfer of
Escherichia coli
O157:H7 from contaminated manure to fresh produce, lettuce seedlings were transplanted into soil fertilized with bovine manure which had been inoculated with approximately 10
4
CFU g
−1
E. coli
O157:H7. The lettuce was grown for approximately 50 days in beds in climate-controlled rooms in a greenhouse. As the bacterium was not detected in the edible parts of the lettuce, the outer leaves of the lettuce, or the lettuce roots at harvest it was concluded that transmission of
E. coli
O157:H7 from contaminated soil to lettuce did not occur. The pathogen persisted in the soil for at least 8 weeks after fertilizing but was not detected after 12 weeks. Indigenous
E. coli
was detected only sporadically on the lettuce at harvest, and enterococci were not detected at all. The numbers of enterococci declined more rapidly than those of
E. coli
in the soil.
Pseudomonas fluorescens
, which inhibited growth of
E. coli
O157:H7 in vitro, was isolated from the rhizosphere.
Relationship between Bacterioplankton Richness, Respiration, and Production in the Southern North Sea
Authors: Reinthaler Thomas , Winter Christian , Herndl Gerhard J. 
Published: May 2005

ABSTRACT

We investigated the relationship between bacterioplankton production (BP), respiration (BR), and community composition measured by terminal restriction fragment length polymorphism in the southern North Sea over a seasonal cycle. Major changes in bacterioplankton richness were apparent from April to December. While cell-specific BP decreased highly significantly with increasing bacterioplankton richness, cell-specific BR was found to be variable along the richness gradient, suggesting that bacterioplankton respiration is rather independent from shifts in the bacterial community composition. As a consequence, the bacterial growth efficiency [BGE = BP/(BP + BR)] was negatively related to bacterioplankton richness, explaining ∼43% of the variation in BGE. Our results indicate that despite the observed shifts in the community composition, the main function of the bacterioplankton, the remineralization of dissolved organic carbon to CO
2
, is rather stable.
Metabolic Network Analysis of
Streptomyces tenebrarius
, a
Streptomyces
Species with an Active Entner-Doudoroff Pathway
Authors: Borodina Irina , Schöller Charlotte , Eliasson Anna , Nielsen Jens 
Published: May 2005

ABSTRACT

Streptomyces tenebrarius
is an industrially important microorganism, producing an antibiotic complex that mainly consists of the aminoglycosides apramycin, tobramycin carbamate, and kanamycin B carbamate. When
S. tenebrarius
is used for industrial tobramycin production, kanamycin B carbamate is an unwanted by-product. The two compounds differ only by one hydroxyl group, which is present in kanamycin carbamate but is reduced during biosynthesis of tobramycin.
13
C metabolic flux analysis was used for elucidating connections between the primary carbon metabolism and the composition of the antibiotic complex. Metabolic flux maps were constructed for the cells grown on minimal medium with glucose or with a glucose-glycerol mixture as the carbon source. The addition of glycerol, which is more reduced than glucose, led to a three-times-greater reduction of the kanamycin portion of the antibiotic complex. The labeling indicated an active Entner-Doudoroff (ED) pathway, which was previously considered to be nonfunctional in
Streptomyces
. The activity of the pentose phosphate (PP) pathway was low (10 to 20% of the glucose uptake rate). The fluxes through Embden-Meyerhof-Parnas (EMP) and ED pathways were almost evenly distributed during the exponential growth on glucose. During the transition from growth phase to production phase, a metabolic shift was observed, characterized by a decreased flux through the ED pathway and increased fluxes through the EMP and PP pathways. Higher specific NADH and NADPH production rates were calculated in the cultivation on glucose-glycerol, which was associated with a lower percentage of nonreduced antibiotic kanamycin B carbamate.
Contribution of
Archaea
to Total Prokaryotic Production in the Deep Atlantic Ocean
Authors: Herndl Gerhard J. , Reinthaler Thomas , Teira Eva , van Aken Hendrik , Veth Cornelius , Pernthaler Annelie , Pernthaler Jakob 
Published: May 2005

ABSTRACT

Fluorescence in situ hybridization (FISH) in combination with polynucleotide probes revealed that the two major groups of planktonic
Archaea
(
Crenarchaeota
and
Euryarchaeota
) exhibit a different distribution pattern in the water column of the Pacific subtropical gyre and in the Antarctic Circumpolar Current system. While
Euryarchaeota
were found to be more dominant in nearsurface waters,
Crenarchaeota
were relatively more abundant in the mesopelagic and bathypelagic waters. We determined the abundance of archaea in the mesopelagic and bathypelagic North Atlantic along a south-north transect of more than 4,000 km. Using an improved catalyzed reporter deposition-FISH (CARD-FISH) method and specific oligonucleotide probes, we found that archaea were consistently more abundant than bacteria below a 100-m depth. Combining microautoradiography with CARD-FISH revealed a high fraction of metabolically active cells in the deep ocean. Even at a 3,000-m depth, about 16% of the bacteria were taking up leucine. The percentage of
Euryarchaeota
and
Crenarchaeaota
taking up leucine did not follow a specific trend, with depths ranging from 6 to 35% and 3 to 18%, respectively. The fraction of
Crenarchaeota
taking up inorganic carbon increased with depth, while
Euryarchaeota
taking up inorganic carbon decreased from 200 m to 3,000 m in depth. The ability of archaea to take up inorganic carbon was used as a proxy to estimate archaeal cell production and to compare this archaeal production with total prokaryotic production measured via leucine incorporation. We estimate that archaeal production in the mesopelagic and bathypelagic North Atlantic contributes between 13 to 27% to the total prokaryotic production in the oxygen minimum layer and 41 to 84% in the Labrador Sea Water, declining to 10 to 20% in the North Atlantic Deep Water. Thus, planktonic archaea are actively growing in the dark ocean although at lower growth rates than bacteria and might play a significant role in the oceanic carbon cycle.
Reduced Proteolysis of Secreted Gelatin and Yps1-Mediated α-Factor Leader Processing in a
Pichia pastoris kex2
Disruptant
Authors: Werten Marc W. T. , de Wolf Frits A. 
Published: May 2005

ABSTRACT

Heterologous proteins secreted by yeast and fungal expression hosts are occasionally degraded at basic amino acids. We cloned
Pichia pastoris
homologs of the
Saccharomyces cerevisiae
basic residue-specific endoproteases Kex2 and Yps1 to evaluate their involvement in the degradation of a secreted mammalian gelatin. Disruption of the
P. pastoris KEX2
gene prevented proteolysis of the foreign protein at specific monoarginylic sites. The
S. cerevisiae
α-factor preproleader used to direct high-level gelatin secretion was correctly processed at its dibasic site in the absence of the prototypical proprotein convertase Kex2. Disruption of the
YPS1
gene had no effect on gelatin degradation or processing of the α-factor propeptide. When both the
KEX2
and
YPS1
genes were disrupted, correct precursor maturation no longer occurred. The different substrate specificities of both proteases and their mutual redundancy for propeptide processing indicate that
P. pastoris kex2
and
yps1
single-gene disruptants can be used for the α-factor leader-directed secretion of heterologous proteins otherwise degraded at basic residues.
Construction, Analysis, and β-Glucanase Screening of a Bacterial Artificial Chromosome Library from the Large-Bowel Microbiota of Mice
Authors: Walter Jens , Mangold Marco , Tannock Gerald W. 
Published: May 2005

ABSTRACT

A metagenomic (community genomic) library consisting of 5,760 bacterial
artificial chromosome clones was prepared in
Escherichia coli
DH10B from DNA extracted from the large-bowel microbiota of BALB/c
mice. DNA inserts detected in 61 randomly chosen clones averaged 55 kbp
(range, 8 to 150 kbp) in size. A functional screen of the library forβ
-glucanase activity was conducted using lichenin agar plates
and Congo red solution. Three clones with β-glucanase activity
were detected. The inserts of these three clones were sequenced and
annotated. Open reading frames (ORF) that encoded putative proteins
with identity to glucanolytic enzymes (lichenases and laminarinases)
were detected by reference to databases. Other putative genes were
detected, some of which might have a role in environmental sensing,
nutrient acquisition, or coaggregation. The insert DNA from two clones
probably originated from uncultivated bacteria because the ORF had low
sequence identity with database entries, but the genes associated with
the remaining clone resembled sequences reported in
Bacteroides
species.
Utilization of the Plant Hormone Indole-3-Acetic Acid for Growth by
Pseudomonas putida
Strain 1290
Authors: Leveau Johan H. J. , Lindow Steven E. 
Published: May 2005

ABSTRACT

We have isolated from plant surfaces several bacteria with the ability to catabolize indole-3-acetic acid (IAA). One of them, isolate 1290, was able to utilize IAA as a sole source of carbon, nitrogen, and energy. The strain was identified by its 16S rRNA sequence as
Pseudomonas putida
. Activity of the enzyme catechol 1,2-dioxygenase was induced during growth on IAA, suggesting that catechol is an intermediate of the IAA catabolic pathway. This was in agreement with the observation that the oxygen uptake by IAA-grown
P. putida
1290 cells was elevated in response to the addition of catechol. The inability of a
catR
mutant of
P. putida
1290 to grow at the expense of IAA also suggests a central role for catechol as an intermediate in IAA metabolism. Besides being able to destroy IAA, strain 1290 was also capable of producing IAA in media supplemented with tryptophan. In root elongation assays,
P. putida
strain 1290 completely abolished the inhibitory effect of exogenous IAA on the elongation of radish roots. In fact, coinoculation of roots with
P. putida
1290 and 1 mM concentration of IAA had a positive effect on root development. In coinoculation experiments on radish roots, strain 1290 was only partially able to alleviate the inhibitory effect of bacteria that in culture overproduce IAA. Our findings imply a biological role for strain 1290 as a sink or recycler of IAA in its association with plants and plant-associated bacteria.