bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyclic phosphatidic acid elicits neurotrophin‐like actions in embryonic hippocampal neurons
Authors: Fujiwara Yuko , Sebök Agnes , Meakin Susan , Kobayashi Tetsuyuki , Murakami‐Murofushi Kimiko , Tigyi Gabor 
Published: November 2003

AbstractCyclic phosphatidic acid (cPA; 1‐acyl‐sn‐glycerol‐2,3‐cyclic phosphate) is an analog of the growth factor‐like phospholipid mediator lysophosphatidic acid (LPA). As brain tissue is the richest source of cPA we tested its effects on hippocampal neurons from day 16/17 embryonic rat cultured in a serum‐free medium. Nanomolar concentrations of cPA elicited a neurotrophic effect and promoted neurite outgrowth that exceeded that of 50 ng/mL nerve growth factor (NGF). Pertussis toxin, the LPA1/LPA3 receptor‐selective antagonist dioctylglycerol pyrophosphate, the myristoylated inhibitory pseudosubstrate peptide of protein kinase A (PKI), Wortmannin and PD98059 abolished the neurite‐promoting effect. cPA elicited a sustained activation of extracellular signal‐related kinases (ERK) 1/2 and Akt. Clostridium difficile toxin B, an inhibitor of the Rho family of GTPases, reduced cPA‐induced enhancement of neurite outgrowth. In B5P cells, a clonal cell line of PC12 cells overexpressing tyrosine kinase NGF receptor (TrkA), cPA elicited transphosphorylation of TrkA. cPA‐elicited ERK activation was blocked by K252a and PKI. These results suggest that cPA mimics the effects of, and activates signaling pathways similar to, the neurotrophin NGF in cultured embryonic hippocampal neurons and B5P cells.
Isolation and characterization of 43 microsatellite DNA markers for guppy (Poecilia reticulata)
Authors: Watanabe T. , Yoshida M. , Nakajima M. , Taniguchi N. 
Published: November 2003

AbstractThirty‐nine polymorphic microsatellite DNA markers were isolated from the guppy (Poecilia reticulata) genomic library. All of the loci showed moderate allelic variation ranging from two to seven alleles, with observed heterozygosities from 0.000 to 0.938. The microsatellite DNA markers isolated will be available for use in analysis of quantitative trait loci in breeding programmes and for population genetic studies on experimental fish.
Isolation and characterization of highly polymorphic microsatellite markers from the marine invasive species Crepidula fornicata (Gastropoda: Calyptraeidae)
Authors: Dupont L. , Viard F. 
Published: November 2003

AbstractMany marine organisms have pelagic larvae and these are often important agents of dispersal and establishment of exotic species. The larval phase and the hermaphroditic reproductive system of the invasive marine gastropod Crepidula fornicata are crucial in determining the success of this species along the European coasts. To analyse these factors, we developed seven microsatellite loci specific to C. fornicata. On the same set of individuals, the microsatellite loci exhibited a greater level of polymorphism than previously studied allozyme markers and, thus, will permit fine‐scale analysis and larval pool studies.
Thirty‐four polymorphic microsatellites for European roe deer
Authors: Vial L. , Maudet C. , Luikart G. 
Published: November 2003

AbstractThe European roe deer (Capreolus capreolus) is an interesting model for molecular ecology studies because of its abundance and adaptability across a range of environments (including human‐modified habitats), and because of its increasing impacts on agricultural crops and on regenerating forests. We identify polymorphic microsatellites in two managed populations of roe deer in France by using cross‐species amplification of primers from other Cervids and from Bovids. Of the 62 primer pairs tested, 45 amplified microsatellites in roe deer, and 34 were polymorphic. Eleven primer pairs were selected for multiplex gel‐loading for routine genotyping of the studied populations.
Microsatellite loci isolated from narrow‐leaved cattail Typha angustifolia
Authors: Tsyusko‐Omeltchenko Olga V. , Schable Nancy A. , Smith Michael H. , Glenn Travis C. 
Published: November 2003

AbstractWe present 11 dinucleotide microsatellite DNA loci isolated from the narrow‐leaved cattail (Typha angustifolia) and describe conditions for their amplification. The PCR primers were tested on at least 20 individuals of Typha angustifolia and T. latifolia from two Ukrainian populations per species. The primers amplify loci with relatively high numbers of alleles (averaging 7.22 and 4.95 alleles per locus in T. angustifolia and T. latifolia, respectively), and polymorphic information content (averaging 0.61 and 0.46 in T. angustifolia and T. latifolia, respectively).
Development and characterization of polymorphic microsatellite markers from Fragaria viridis, a wild diploid strawberry
Authors: Sargent D. J. , Hadonou A. M. , Simpson D. W. 
Published: November 2003

AbstractTo date, the development of microsatellite (SSR) markers in the genus Fragaria has focused on F. vesca. However, further species are thought to have contributed to the complex allo‐octoploid genome of the cultivated strawberry, F.×ananassa. Here, we present 22 new SSR markers developed from the diploid species F. viridis. Twenty‐one of the primer pairs amplified polymorphisms in six F. viridis accessions, with an average of 4.95 alleles per primer pair and an average expected heterozygosity of 0.68. Fourteen of these primer pairs, and a locus monomorphic in F. viridis, amplified polymorphic alleles in the parents of a F. vesca mapping population.
Novel polymorphic microsatellite markers for the common pandora (Pagellus erythrinus)
Authors: RamŠak Andreja , Garoia Flavio , Guarniero Ilaria , Mannini Piero , Tinti Fausto 
Published: November 2003

AbstractDetails of six highly polymorphic dinucleotide and one highly polymorphic tetranucleotide microsatellite markers are provided for Pagellus erythrinus. These markers are highly polymorphic, with an expected heterozygosity ranging from 0.713 to 0.959 and allele numbers ranging from seven to 36. These microsatellite markers should help determine population genetic structure and fisheries stocks for management purposes.
Development of microsatellite DNA loci from the wood stork (Aves, Ciconiidae, Mycteria americana)
Authors: Tomasulo‐Seccomandi Alessandra M. , Schable Nancy A. , Lawrence Bryan A. , Lehr Brisbin I. , Del Lama Silvia N. , Glenn Travis C. 
Published: November 2003

AbstractWe isolated 11 polymorphic microsatellite loci for wood stork (Mycteria americana). Polymerase chain reaction (PCR) primers and conditions are described for the amplification of five dinucleotide, one trinucleotide and five tetranucleotide microsatellite loci. The PCR primers were tested on two wood stork populations, Fazenda Ipiranga, Mato Grosso, Brazil (n = 11) and Tamiami West, Everglades, Florida, USA (n = 20). The primers yielded two to four alleles per locus, an observed heterozygosity of 0.0–0.727 and a polymorphic information content of 0.048–0.604. The low level of polymorphism for these markers is consistent with previous studies of this species.
PCR primers for microsatellite loci in the desert tortoise (Gopherus agassizii, Testudinidae)
Authors: Edwards Taylor , Goldberg Caren S. , Kaplan Matthew E. , Schwalbe Cecil R. , Swann Don E. 
Published: November 2003

AbstractThe desert tortoise, Gopherus agassizii, is a threatened species native to the North American desert southwest and is recognized as having distinct Mojave and Sonoran populations. We identified six polymorphic microsatellite loci in the desert tortoise. All six loci were polymorphic in Sonoran samples. Five of the loci were variable in Mojave samples with varying degrees of amplification success. Two of the loci exhibited low allelic variation (2–3 alleles) while four were highly variable (8–27 alleles).
Microsatellite isolation and characterization in the beneficial parasitoid wasp Diaeretiella rapae (M’Intosh) (Hymenoptera: Braconidae: Aphidiinae)
Authors: Macdonald C. , Brookes C. P. , Edwards K. J. , Baker D. A. , Lockton S. , Loxdale H. D. 
Published: November 2003

AbstractThe primary parasitoid wasp, Diaeretiella rapae (M’Intosh), is used as a biological control agent in insect pest management strategies to combat aphid pests, mainly on cruciferous plants. To investigate the spatial scales over which this beneficial parasitoid wasp moves within an agricultural landscape, we developed five polymorphic microsatellite markers. The number of alleles per locus ranged from 11 to 21. Cross‐species amplification indicated that these loci may be useful in some other members of the Aphidiinae.
Isolation and characterization of microsatellite loci in the flour mite Acarus siro
Authors: Learmount J. , Conyers C. M. , Chaudhry M. Q. , Macnicoll A. D. 
Published: November 2003

AbstractThirteen microsatellites with dinucleotide repeats were isolated from genomic DNA in solution by hybridization capture. Eleven were evaluated against Acarus siro using a multiple‐tube approach to assess polymorphism and reliability of the results. The multiple‐tube method demonstrated the presence of null alleles due to low levels of DNA. Seven of the 11 microsatellite loci were polymorphic and six produced reliable amplification products, if results only from individuals that scored at all six loci were used in the analysis. These were evaluated in eight strains of A. siro. Two of the samples showed some genetic divergence using FST values.
Characterization of twenty‐four microsatellite markers for rainbow trout (Oncorhynchus mykiss)
Authors: Rodriguez F. , Rexroad C. E. , Palti Y. 
Published: November 2003

AbstractTwenty‐four new microsatellite markers were developed for genome mapping and population genetics studies in rainbow trout (Oncorhynchus mykiss). The amount of polymorphism, percentage heterozygosity and ability of each marker to amplify genomic DNA from other salmonids were recorded. Seven markers were observed to be duplicated in the rainbow trout genome by containing more than one allele in homozygous (clonal) fish.
bottlesim: a bottleneck simulation program for long‐lived species with overlapping generations
Authors: Kuo C.‐H. , Janzen F. J. 
Published: November 2003

AbstractPopulation bottlenecks reduce genetic diversity and thus cause great concern in conservation biology. Previous theoretical studies often assume discrete generations in projecting declines in genetic diversity caused by bottlenecks. This assumption creates complexities when applying the models to long‐lived species with overlapping generations. bottlesim is a program for simulating bottlenecks to estimate the impact on genetic diversity; the novelties include an overlapping‐generation model, a wide range of reproductive systems, and flexible population size settings. With these features, bottlesim will be a useful tool for estimating the genetic consequences of bottlenecks, evaluating conservation plans, and performing power analysis.
Black as Me: Narrative Identity
Authors: Baylis Françoise 
Published: November 2003

ABSTRACTThis commentary responds to genetic testing of African ancestry through a series of personal narratives that reveal a complex, intimate, and individualised process of identity formation. The author discusses both how her family and others outside her family have fostered and challenged her sense of black identity. She concludes by maintaining that racial identity is not in the genes but in the world in which we live and the stories we construct and are able to maintain.
Genomics of Helicobacter 2003
Authors: Björkholm Britta , Salama Nina R. 
Published: November 2003

ABSTRACTResearch on Helicobacter pylori has been driven by the field of genomics since the release of the first of two complete genome sequences in 1997. In this review we highlight progress made in the last year. New bioinformatics tools and methods promise better functional and strain comparative analyses of individual genes. Sequence‐based methods of strain comparison documented the coevolution of H. pylori with human populations. Several comprehensive analyses of the bacterial transcriptome were undertaken as well as two sophisticated studies of the transcriptional response of specific host tissues in response to H. pylori infection using different mouse models of H. pylori diseases. Some progress was made in developing genetic tools for mutational analysis of the genes required for infection. Finally, proteomic approaches were refined to delineate surface exposed and secreted proteins that represent potential antigens. In summary, while we do not have the full story of H. pylori, significant progress in deciphering the genome into functional biology has been made.
Helicobacter pylori– inflammation, immunity and vaccines
Authors: Michetti Pierre , Svennerholm Ann‐Mari 
Published: November 2003

ABSTRACTThe mechanisms by which Helicobacter pylori escape the host immune response remains an important topic. Regulatory T cells appear to play a role in the persistence of the infection and the control of tissue damage. In the thought that the host genetic background influences the cross‐talk between pathogens and hosts, the impact of cytokine polymorphisms on the outcome of H. pylori has been further delineated in the review period. On the other hand, several additional genes of H. pylori have been shown to participate in the pro‐inflammatory cytokine and chemokine response to the infection. Finally, progress has been achieved in vaccine development, with new vaccine delivery systems and routes of immunization tested in animal models and human volunteers.
Helicobacter pylori infection in pediatrics
Authors: Wewer Vibeke , Kalach Nicolas 
Published: November 2003

ABSTRACTA high prevalence and early colonization of Helicobacter pylori infection in childhood was described again this year in developing countries in contrast to developed ones. Upper gastrointestinal endoscopy including gastric biopsies remains the diagnostic gold standard method for this infection. Also noninvasive tests have been studied in children, including serology, 13C‐urea breath test and stool antigen test, showing good results in the different age groups as compared to the gold standard. However, the infection often remains asymptomatic in children and the role of this bacterium in gastric manifestations is the subject of conflicting reports. Extra‐digestive manifestations are also reported in the course of this infection. The treatment of H. pylori infection is influenced by resistance of the bacteria to the antibiotics used. We suggest that eradication of H. pylori should take place only after susceptibility testing. The association of a proton pump inhibitor and two antibiotics for 1 or 2 weeks gives the best eradication rates. The crucial question to elucidate is whether asymptomatic children should be treated to prevent cancer in the future.
Helicobacter pylori and extragastric diseases – Other Helicobacters
Authors: Gasbarrini Antonio , Carloni Emilia , Gasbarrini Giovanni , Ménard Armelle 
Published: November 2003

ABSTRACTThe role of Helicobacter pylori infection is explored in more and more extragastric diseases without definite proof in most of the studies, except possibly some hematologic diseases. In cardiovascular diseases, including stroke, the presence of CagA positive strains may be involved. The possible role of helicobacters in hepatobiliary diseases goes beyond that of H. pylori to involve enterohepatic helicobacters. New Helicobacter species are regularly described and molecular methods are developed to improve their detection. Helicobacter felis remains the major species to be used in animal models of Helicobacter infection.
Development of an Optrode for Intramural Multisite Optical Recordings of Vm in the Heart
Authors: BYARS JONATHAN L. , SMITH WILLIAM M. , IDEKER RAYMOND E. , FAST VLADIMIR G. 
Published: November 2003

Introduction: Optical mapping of transmembrane potential (Vm) is an important tool in the investigation of impulse propagation in the heart. It provides valuable information about spatiotemporal changes of Vm that cannot be obtained by other techniques, but it presently is limited to measurements from the heart surfaces. Therefore, the goal of this work was to develop a technique for intramural multisite optical measurements of Vm using fiberoptic technology. Methods and Results: An optrode, a bundle of thin optical fibers, was developed for measuring intramural optical signals at multiple sites in the heart. The optrode consisted of seven fibers with diameter of 225 μm arranged in a hexagonal pattern that were used to deliver excitation light to the myocardium, to collect the emitted fluorescence, and to project the light onto a 16 × 16 array of photodiode detectors. Rabbit hearts were stained with the Vm‐sensitive dye RH‐237. Fluorescence was excited using a 100‐W Hg lamp. Intramural action potentials were recorded at multiple sites separated by 2 mm inside the left ventricle. Signal‐to‐noise (RMS) ratio was 21.2 ± 12 (n = 7) without averaging or ratiometry and with negligible cross‐talk (<1.9%) between the neighboring photodiodes. The size of the recording area for an individual fiber was estimated at approximately 0.8 mm. Conclusion: These data demonstrate feasibility of multisite transmural measurements of Vm without signal averaging and ratiometry. This technique might become useful in studies of transmural impulse conduction during arrhythmias and defibrillation. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1196‐1202, November 2003)
Arterial desaturation during exercise in man: implication for O2 uptake and work capacity
Authors: Nielsen Henning Bay 
Published: November 2003

Exercise‐induced arterial hypoxaemia is defined as a reduction in the arterial O2 pressure (PaO2) by more than 1 kPa and/or a haemoglobin O2 saturation (SaO2) below 95%. With blood gas analyses ideally reported at the actual body temperature, desaturation is a consistent finding during maximal ergometer rowing. Arterial desaturation is most pronounced at the end of a maximal exercise bout, whereas the reduction in PaO2 is established from the onset of exercise. Exercise‐induced arterial hypoxaemia is multifactorial. The ability to maintain a high alveolar O2 pressure (PAO2) is critical for blood oxygenation and this appears to be difficult in large individuals. A large lung capacity and, in turn, diffusion capacity seem to protect PaO2. A widening of the PAO2–PaO2 difference does indicate that a diffusion limitation, a ventilation–perfusion mismatch and/or a shunt influence the transport of O2 from alveoli to the pulmonary capillaries. An inspired O2 fraction of 0.30 reduces the widened PAO2–PaO2 difference by 75% and prevents a reduction of PaO2 and SaO2. With a marked increase in cardiac output, diffusion limitation combined with a fast transit time dominates the O2 transport problem. Furthermore, a postexercise reduction in pulmonary diffusion capacity suggests that the alveolo‐capillary membrane is affected. An antioxidant attenuates oxidative burst by neutrophilic granulocytes, but it does not affect PaO2, SaO2 or O2 uptake (VO2), and the ventilatory response to maximal exercise also remains the same. It is proposed, though, that increased concentration of certain cytokines correlates to exercise‐induced hypoxaemia as cytokines stimulate mast cells and basophilic granulocytes to degranulate histamine. The basophil count increases during maximal rowing. Equally, histamine release is associated with hypoxaemia and when the release of histamine is prevented, the reduction in PaO2 is attenuated.During maximal exercise, an extreme lactate spill‐over to blood allows pH decrease to below 7.1 and according to the O2 dissociation curve this is critical for SaO2. When infusion of sodium bicarbonate maintains a stable blood buffer capacity, acidosis is attenuated and SaO2 increases from 89% to 95%. This enables exercise capacity to increase, an effect also seen when O2 supplementation to inspired air restores arterial oxygenation. In that case, exercise capacity increases less than can be explained by VO2 and CaO2. Furthermore, the change in muscle oxygenation during maximal exercise is not affected when hyperoxia and sodium bicarbonate attenuate desaturation. It is proposed that other organs benefit from enhanced O2 availability, and especially the brain appears to increase its oxygenation during maximal exercise with hyperoxia.
Identification and Characterization of the Nickel Uptake System for Urease Biogenesis in
Streptococcus salivarius
57.I
Authors: Chen Yi-Ywan M. , Burne Robert A. 
Published: November 2003

ABSTRACT

Ureases are multisubunit enzymes requiring Ni
2+
for activity. The low pH-inducible urease gene cluster in
Streptococcus salivarius
57.I is organized as an operon, beginning with
ureI
, followed by
ureABC
(structural genes), and
ureEFGD
(accessory genes). Urease biogenesis also requires a high-affinity Ni
2+
uptake system. By searching the partial genome sequence of a closely related organism,
Streptococcus thermophilus
LMG18311, three open reading frame (ORFs) homologous to those encoding proteins involved in cobalamin biosynthesis and cobalt transport (
cbiMQO
) were identified immediately 3′ to the
ure
operon. To determine whether these genes were involved in urease biogenesis by catalyzing Ni
2+
uptake in
S. salivarius
, regions 3′ to
ureD
were amplified by PCRs from
S. salivarius
by using primers identical to the
S. thermophilus
sequences. Sequence analysis of the products revealed three ORFs. Reverse transcriptase PCR was used to demonstrate that the ORFs are transcribed as part of the
ure
operon. Insertional inactivation of ORF1 with a polar kanamycin marker completely abolished urease activity and the ability to accumulate
63
Ni
2+
during growth. Supplementation of the growth medium with NiCl
2
at concentrations as low as 2.5 μM partially restored urease activity in the mutant. Both wild-type and mutant strains showed enhanced urease activity when exogenous Ni
2+
was provided at neutral pH. Enhancement of urease activity by adding nickel was regulated at the posttranslational level. Thus, ORF1, ORF2, and ORF3 are part of the
ure
operon, and these genes, designated
ureM
,
ureQ
, and
ureO
, respectively, likely encode a Ni
2+
-specific ATP-binding cassette transporter.
Factors Contributing to Hydrogen Peroxide Resistance in
Streptococcus pneumoniae
Include Pyruvate Oxidase (SpxB) and Avoidance of the Toxic Effects of the Fenton Reaction
Authors: Pericone Christopher D. , Park Sunny , Imlay James A. , Weiser Jeffrey N. 
Published: November 2003

ABSTRACT

Aerobic growth of
Streptococcus pneumoniae
results in production of amounts of hydrogen peroxide (H
2
O
2
) that may exceed 1 mM in the surrounding media. H
2
O
2
production by
S. pneumoniae
has been shown to kill or inhibit the growth of other respiratory tract flora, as well as to have cytotoxic effects on host cells and tissue. The mechanisms allowing
S. pneumoniae
, a catalase-deficient species, to survive endogenously generated concentrations of H
2
O
2
that are sufficient to kill other bacterial species is unknown. In the present study, pyruvate oxidase (SpxB), the enzyme responsible for endogenous H
2
O
2
production, was required for survival during exposure to high levels (20 mM) of exogenously added H
2
O
2
. Pretreatment with H
2
O
2
did not increase H
2
O
2
resistance in the mutant, suggesting that SpxB activity itself is required, rather than an H
2
O
2
-inducible pathway.
SpxB
mutants synthesized 85% less acetyl-phosphate, a potential source of ATP. During H
2
O
2
exposure, ATP levels decreased more rapidly in
spxB
mutants than in wild-type cells, suggesting that the increased killing of
spxB
mutants was due to more rapid ATP depletion. Together, these data support the hypothesis that
S. pneumoniae
SpxB contributes to an H
2
O
2
-resistant energy source that maintains viability during oxidative stress. Thus, SpxB is required for resistance to the toxic by-product of its own activity. Although H
2
O
2
-dependent hydroxyl radical production and the intracellular concentration of free iron were similar to that of
Escherichia coli
, killing by H
2
O
2
was unaffected by iron chelators, suggesting that
S. pneumoniae
has a novel mechanism to avoid the toxic effects of the Fenton reaction.