bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of effects of rofecoxib on platelet function in an in vitro model of thrombosis with circulating human blood
Authors: Hernandez M. R. , Tonda R. , Pino M. , Serradell M. , Arderiu G. , Escolar G. 
Published: April 2004

AbstractBackground  Cyclooxygenase (COX)‐2‐selective non‐steroidal anti‐inflammatory drugs have been used for anti‐inflammatory therapy. However, it has also been described that they may increase risk of cardiovascular events.Objectives  To study the effects of COX2 inhibitor rofecoxib on platelet function using in vitro tests. Results were compared with those obtained in a parallel experiment with acetyl salicylic acid (ASA).Methods  Studies of platelet aggregation, using different agonists, were performed by a turbidimetric method. Adhesive and cohesive function of platelets were analyzed by perfusion techniques, treated blood was exposed to thrombogenic surfaces and platelet interaction was morphometrically evaluated.Results  Twenty‐five µM of rofecoxib induced a prolonged lag time and a reduction in the percentage of aggregation when arachidonic acid, ADP or collagen were used as agonists. In perfusion studies with parallel chamber rofecoxib 50 µM and ASA 500 µM reduced overall platelet interaction with the collagen surface (17·4 ± 3·7, P < 0·05; vs. 32·1 ± 2·6%P < 0·05 and 17·9 ± 2·4, vs. 31·9 ± 3·24, P < 0·05, respectively). In studies performed on annular chambers, 25 µM of rofecoxib reduced platelet interaction; values of the thrombus and covered surface were 17·4 ± 4·5%; P < 0·05 and 21·1 ± 4·1%; P < 0·05, respectively, vs. 30·4 ± 7·5% and 33·5 ± 6·5 in the control. ASA did also impair thrombus formation but differences did not reach the levels of statistical significance. Moreover, rofecoxib but not ASA reduced significantly thrombus height and thrombus area (7·4 ± 0·5 µM; P < 0·005 and 96·0 ± 21·2 µM2; P < 0·05 vs. control 11·2 ± 0·9 µM and 220·0 ± 47·7µM2, respectively).Conclusion  We conclude that under our experimental conditions, rofecoxib diminished platelet aggregation induced by different agonists and inhibited platelet‐mediated thrombogenesis in an in vitro model of thrombosis.
2004 Spring Scientific Meeting of the British Endodontic Society
Authors: Desai M. , Gulabivala K. , Ng Y.‐L. , Spratt D. 
Published: April 2004

Co‐aggregation studies on bacteria from infected root canalsAim  Co‐aggregation phenomena may play a crucial role in root canal colonization and subsequent infection, and may be an important aspect of the selection process taking place. The aims were to determine intracanal and intercanal co‐aggregation partners in bacterial strains isolated from infected root canal systems.Methodology  Bacterial strains isolated from the root canals of four intact teeth, and one strain of Fusobacterium nucleatum from a separate tooth were selected for the study. The isolates were grown in static culture at 37 °C in brain heart infusion broth. The cells were harvested by centrifugation and prepared for the co‐aggregation study in an appropriate buffer. Aliquots (100 µL) of each pair of isolates (all combinations) were placed in a durham tube, mixed and left to settle. A visual co‐aggregation assay was performed after 1–2 h after pairing and again 6–7 h later. Co‐aggregation was judged by a predetermined 5‐point visual assessment scale, which showed good reproducibility.Results  Co‐aggregation results were identical at the different time points. Physical interaction between bacterial cells within a genus and between different genera was surprisingly infrequent; where it manifested in auto‐aggregation (within strain) or co‐aggregation, it was found to be species‐ and strain‐specific. Actinomyces viscosus, Rothia dentocariosa, Streptomyces scabei, Neiserria mucosa and two unidentified strains displayed auto‐aggregation. Intrageneric and intergeneric co‐aggregation was observed both between strains from the same tooth and those from different teeth. Sometimes, strains that showed no intracanal co‐aggregation were identified as co‐aggregation partners with strains from different teeth. Intrageneric co‐aggregation occurred between Streptococcus species, and intergeneric co‐aggregation involved Abiotrophia adiacens, A. naeslundii, Pediococcus urinaeequii, R. dentocariosa, S. scabei, Streptococcus gordonii and S. mitis. The F. nucleatum strain tested for co‐aggregation did not auto‐aggregate or co‐aggregate with any of the isolates it was paired with.Conclusions  This study showed that co‐aggregation is species‐ and strain‐dependent, and was surprisingly infrequent among the various pairings. The renowned associations between root canal isolates may be dominated by interactions other than physical, such as nutritional and physiological dependence.
Utilization of relevant nutritional resources by root canal isolates
Authors: Khot A. , Spratt D. , Ng Y.‐L. , Gulabivala K. 
Published: April 2004

Aim  To identify nutritional sources potentially available within the root canal systems that may allow the growth of bacteria.Methodology  All the cultivable bacterial species (Aerococcus viridans, Actinomyces viscosus, Rothia dentocariosa, Streptococcus mitis, Corynebacterium durum, Pediococcus urinaeequi, Campylobacter gracilis, Fusobacterium nucleatum and Prevotella corporis) from a single tooth infection were used. The nutrient sources tested included those potentially available from teeth (enamel, dentine, cementum, pulp tissue, saliva, serum and blood), artificial media (reduced transport fluid (RTF), brain heart infusion (BHI) and nutrient broth) and a control (phosphate‐buffered saline (PBS)). Each medium was inoculated with each of the bacterial isolates in microtitre plates in doubling dilution series. All experiments were carried out in triplicate. The plates were incubated either aerobically or anaerobically, as appropriate. Bacterial growth was assessed as a function of relative optical densities (ODs) at different nutrient dilutions measured by spectrophotometry at 24 and 48 h. Mean values were calculated (n = 3) and the resultant data were analysed to determine the presence or absence of growth.Results  The effectiveness of artificial media in supporting the growth of the isolates was confirmed; BHI supported the growth of all isolates, but nutrient broth supported the growth of only six strains. As expected, PBS and RTF did not support bacterial growth. Of the dental tissues, enamel and dentine did not support bacterial growth, but cementum supported the growth of C. durum and C. gracilis. Pulp tissue only supported the growth of A. viscosus and C. gracilis. The body fluids supported bacterial growth well. Blood supported growth of all bacterial isolates except C. gracilis. Serum supported the growth of all isolates except P. urinaeequi and C. gracilis. Saliva supported the growth of A. viridans, A. viscosus, R. dentocariosa, C. durum and P. urinaeequi.Conclusions  The differential support of growth by the nutrient sources revealed in the present study support the conclusion that during root canal infection, the causative bacteria may derive nutrition from a variety of locally abundant key tissues, but the principal components of hard and soft tissue present within teeth support bacterial growth only to a limited extent or does not support at all. The principal requirements are body fluids.
Phylogeography of a game species: the red‐crested pochard (Netta rufina) and consequences for its management
Authors: Gay L. , Defos Du Rau P. , Mondain‐Monval J‐Y. , Crochet P‐A. 
Published: April 2004

AbstractWestern European populations of red‐crested pochard (Netta rufina) are characterized by low size and high fragmentation, which accentuate their sensitivity to hunting. Uncertainties regarding the demographic trends of these populations highlight the need for pertinent hunting regulations. This requires identification of the limits of the populations under exploitation, i.e. delimiting a management unit. We used the left domain of the mitochondrial control region and seven nuclear loci (four microsatellites and three introns) to assess the level of genetic structure and demographic independence between the fragmented Western European and the large Central Asian populations. The second objective was to investigate the colonization history of the Western European populations. This study demonstrated that the Western European populations of red‐crested pochard constitute a separate demographic conservation unit relative to the Asian population as a result of very low female dispersal (mitochondrial DNA: ΦST = 0.152). A morphometric analysis further suggested that Central Asian and Western European specimens of both sexes originate from different pools of individuals. Male dispersal seems higher than female dispersal, as suggested by the lack of clear genetic structure for the nuclear markers at this continental scale. Genetic data, in conjunction with historical demographic data, indicate that the current Western European populations probably originate from a recent colonization from Central Asia. As numbers of red‐crested pochards in Western Europe cannot be efficiently supplemented by immigration from the larger Asian populations, a management plan regulating the harvest in Western Europe is required.
Geographically specific heteroplasmy of mitochondrial DNA in the seaweed, Fucus serratus (Heterokontophyta: Phaeophyceae, Fucales)
Authors: Coyer J. A. , Hoarau G. , Stam W. T. , Olsen J. L. 
Published: April 2004

AbstractThe presence of more than one type of mitochondrial DNA within the same organism (mtDNA heteroplasmy) has been reported in vertebrates, invertebrates, basidiomycetes and some angiosperms, but never in marine (macro)algae. We examined sequence differences in a 135‐base pair (bp) region of the nad11 gene in mitochondria of the intertidal rockweed, Fucus serratus, using single‐strand conformation polymorphism (SSCP). Each of 70 and 22 individuals from Blushøj (Denmark) and Oskarshamn (Sweden), respectively, displayed haplotypes 2, 3, and 4 (= mtDNA heteroplasmy), whereas only haplotype 2 was found in each of 24 individuals from locations in Spain, France, Ireland, Iceland and Norway. As Blushøj and Oskarshamn were among the last areas to emerge from ice cover during the Last Glacial Maximum (18 000–20 000 years bp), the geographically specific heteroplasmy may represent a founder effect and therefore, a valuable marker for understanding the role of post‐Ice Age recolonization. Geographically specific heteroplasmy also has important implications in phylogeographical studies based on mtDNA sequences.
Natural hybridization and the evolution of domesticated, pest and disease organisms
Authors: Arnold Michael L. 
Published: April 2004

AbstractThe role of natural hybridization in the evolutionary history of numerous species is well recognized. The impact of introgressive hybridization and hybrid speciation has been documented especially in plant and animal assemblages. However, there remain certain areas of investigation for which natural hybridization and its consequences remain under‐studied and under‐appreciated. One such area involves the evolution of organisms that positively or negatively affect human populations. In this review, I highlight exemplars of how natural hybridization has contributed to the evolution of (i) domesticated plants and animals; (ii) pests; (iii) human disease vectors; and (iv) human pathogens. I focus on the effects from genetic exchange that may lead to the acquisition of novel phenotypes and thus increase the beneficial or detrimental (to human populations) aspects of the various taxa.
Population genetic structure of Arctic Charr, Salvelinus alpinus from northwest Europe on large and small spatial scales
Authors: Wilson A. J. , Gíslason D. , Skúlason S. , Snorrason S. S. , Adams C. E. , Alexander G. , Danzmann R. G. , Ferguson M. M. 
Published: April 2004

AbstractTo examine the population genetic structure of lake‐resident Arctic charr, Salvelinus alpinus from northwest Europe on multiple spatial scales, 2367 individuals from 43 lakes located in three geographical regions (Iceland, the British Isles and Scandinavia) were genotyped at six microsatellite loci. On a large scale, data provided little evidence to support clustering of populations according to geographical region. Hierarchical analysis of molecular variance indicated that, although statistically significant, only 2.17% of the variance in allelic frequencies was partitioned at the among‐region level. Within regions, high levels of genetic differentiation were typically found between lakes regardless of the geographical distance separating them. These results are consistent with the hypothesis of rapid postglacial recolonization of all of northwest Europe from a single charr lineage, with subsequent restriction of gene flow. On a smaller scale, there was evidence for close genetic relationships among lakes from within common drainage basins in Scotland. Thus, interlake genetic structure reflects localized patterns of recent (or contemporary) gene flow superimposed onto a larger scale structure that is largely a result of historical processes. There was also evidence for widespread genetic structuring at the within‐lake level, with sympatric populations detected in 10 lakes, and multilocus heterozygote deficits found in 23 lakes. This evidence of the Wahlund effect was found in all lakes known to contain discrete phenotypic morphs, as well as many others, suggesting that morphs may often represent separate breeding populations, and also that the phenomenon of polymorphism in this species may be more widespread than is currently realized.
Antimalarial efficacy of sulfadoxine–pyrimethamine, amodiaquine and a combination of chloroquine plus sulfadoxine–pyrimethamine in Bundi Bugyo, western Uganda
Authors: Checchi Francesco , Piola Patrice , Kosack Cara , Ardizzoni Elisa , Klarkowski Derryck , Kwezi Eric , Priotto Gerardo , Balkan Suna , Bakyaita Nathan , Brockman Alan , Guthmann Jean‐Paul 
Published: April 2004

SummaryWe report below an in vivo antimalarial efficacy study conducted in 2002 in Bundi Bugyo, a district of western Uganda housing a large displaced population. We tested sulfadoxine–pyrimethamine (SP), amodiaquine (AQ) and the combination chloroquine plus SP (CQ + SP). A total of 268 children with uncomplicated Plasmodium falciparum malaria were followed‐up for 28 days according to WHO recommendations, with PCR genotyping to distinguish late recrudescences from re‐infections. PCR‐adjusted failure proportions at day 28 were 37.0% (34/92, 95% CI 27.1–47.7) in the SP group, 20.6% (14/68, 95% CI 11.7–32.1) in the AQ group and 22.8% (18/79, 95% CI 14.1–33.6) in the CQ + SP group. Early failures were particularly frequent in the SP group (15.2%). Clearance of gametocytes was slower in the SP and CQ + SP groups than in the AQ group. This study suggests that, in Bundi Bugyo, CQ + SP (Uganda's first‐line regimen) will need to be replaced by a more efficacious regimen. Across Uganda, the deployment of SP containing combinations may not be a feasible long‐term strategy. For Bundi Bugyo, we recommend a combination of artesunate and AQ. Our study also confirms previous findings that resistance is considerably underestimated by 14‐day follow‐ups. Antimalarial policy decisions should therefore be based on 28‐day studies, with PCR adjustment to distinguish re‐infections.
Urinary tract infections and genitourinary abnormalities in Cameroonian men
Authors: Yuyun Matthew F. , Angwafo III Fru F. , Koulla‐Shiro Sinata , Zoung‐Kanyi Jimmy 
Published: April 2004

SummaryObjective  To compare the prevalence of genitourinary abnormalities in men diagnosed with urinary tract infection (UTI) in a Cameroonian hospital and those without.Patients and methods  Consecutive adult men aged 18–75 years, whose midstream urine samples were received for microscopy, culture and sensitivity at the microbiology laboratory of the Yaounde University Teaching Hospital, Cameroon, constituted the study population. Genitourinary abnormalities were diagnosed from history, physical examination, abdominal and transrectal ultrasonography, plain abdominal X‐ray, and if indicated urethrocystoscopy and biopsy.Results  Of the 206 patients who qualified, 179 completed the study and 63 (35.2%) were found to have UTI. A total of 41 (65.1%) patients with UTI (mean age 69.2 years) had at least one genitourinary abnormality, compared to 13 (11.2%) of those without UTI (mean age 61.9 years) (P < 0.001). The age‐adjusted prevalence of genitourinary abnormalities was 59.4% in the UTI group and 12.1% in the non‐UTI group (P < 0.001). The most frequent genitourinary abnormality in men with UTI was benign prostatic enlargement, followed by urethral stricture. The crude odds ratio (95% confidence intervals) for UTI associated with genitourinary abnormality was 14.77 (6.80–32.05), and the adjusted odds ratio 11.51 (7.08–29.46).Conclusion  Urological evaluation of Cameroonian men with UTI, using simple history taking, physical examination, ultrasound examination and plain abdominal X‐ray, could have significant clinical benefits in this tropical African region.
Duodenal gastric metaplasia and Helicobacter pylori infection in high and low duodenal ulcer‐prevalent areas in India
Authors: TOVEY FRANK I , HOBSLEY MICHAEL , KAUSHIK SATYENDRA P , PANDEY RAKESH , KURIAN GEORGE , SINGH KARTAR , SOOD AJIT , JEHANGIR ERNEST 
Published: April 2004

AbstractBackground:  Previous reports, based on surgery, showed duodenal ulcer (DU) to be more common in the rice‐eating areas of southern India than in the northern wheat‐eating areas.Aims:  Does this difference persist? Can it be explained by risk factors other than diet?Methods:  A total of 20 053 records from patients undergoing endoscopy for dyspepsia, and 590 endoscopy patients from two northern and two southern centers in India were studied prospectively. Records were scrutinized to determine the relative incidence of DU and non‐ulcer dyspepsia in wheat‐ and rice‐eating areas. Age, sex, length of history, smoking and medication were recorded. Three antral biopsies and one from each duodenal quadrant were taken. A rapid urease test was carried out on one of the antral biopsies; the others were examined for Helicobacter pylori, gastritis, duodenitis and duodenal gastric metaplasia.Results:  The difference in diet‐associated prevalence persisted. No differences in smoking, Helicobacter pylori infection or duodenal gastric metaplasia were found between the two regions, but all three were more common in DU than in non‐ulcer dyspeptic patients from both dietary areas.Conclusions:  The dietary differences between the regions remain the only factor to account for the differences in DU prevalence. A strong interrelationship between duodenal gastric metaplasia and cigarette smoking is demonstrated.
It is Possible to Just Give Money to the Poor
Authors: Hanlon Joseph 
Published: April 2004

AbstractMeghnad Desai of the London School of Economics recently suggested that, rather than ‘giving fifty billion dollars of overseas aid’, we should simply ‘find the poor and give them one dollar a week … That would probably do more to relieve poverty than anything else’. Two experiences in Mozambique of simply handing out money show this is possible. Payments to demobilized soldiers over a two year period and single payments to flood victims were of the order of magnitude suggested by Desai. Rural people had no difficulty cashing cheques and used the money prudently. The money stimulated the rural economy and thus had a development impact. Administrative costs were between 5 and 10 per cent, much less than in other aid projects. Using the Mozambique experience, this article concludes by suggesting that Desai's proposed one dollar per person per week could be paid as a family grant bi‐monthly, which would keep administrative costs low.
Eletriptan for the Short‐term Prophylaxis of Cluster Headache
Authors: Zebenholzer Karin , Wöber Christian , Vigl Marion , Wessely Peter 
Published: April 2004

Background.—A beneficial prophylactic effect from eletriptan 40 mg given to a single patient with cluster headache was observed.Objective.—To further evaluate the efficacy of eletriptan in the short‐term prophylaxis of cluster headache.Methods.—We treated 18 patients; mean age, 40.5 years (standard deviation [SD], 9.9). The number of cluster headache attacks was recorded during a baseline period of 6 days, and during 6 days of treatment with eletriptan 40 mg twice daily. The primary outcome measure was the reduction in the number of attacks during the treatment period.Results.—In the 16 patients who completed the study (2 patients were lost to follow‐up), the mean total number of attacks decreased from 10.9 (SD, 5.6) during baseline to 6.3 (SD, 3.7) during treatment with eletriptan (P= .01) The reduction in the number of attacks exceeded 50% in 6 patients.Conclusion.—This small open‐label study suggests that eletriptan 40 mg twice daily may be useful for the short‐term prophylaxis of cluster headache.
Vectorcardiography Risk Stratifies Emergency Department Chest Pain Patients with Left Ventricular Hypertrophy on the Initial 12‐Lead ECG
Authors: Fesmire Francis M. , Eriksson Sven V. 
Published: April 2004

Background: Vectorcardiographic (VCG) measurements of ST‐vector magnitude (VM) and QRS‐vector difference (VD) have been demonstrated to be independent predictors of adverse outcome (AO) and acute myocardial infarction (AMI) in emergency department (ED) chest pain patients with absence of bundle branch block or left ventricular hypertrophy (LVH) on the initial 12‐lead electrocardiogram (ECG). The prognostic value of ST‐VM and QRS‐VD in ED chest pain patients with LVH on the initial 12‐lead ECG has not been previously investigated. Methods: A prospective observational study was performed in 196 consecutive ED chest pain patients with suspected AMI and presence of voltage criteria for LVH on initial ECG who underwent continuous VCG monitoring during the initial evaluation. The optimal baseline ST‐VM value and 2‐hour QRS‐VD value were defined as the most accurate value on the receiver operator characteristic curve (value with lowest false‐negative and false‐positive rate). Thirty‐day AO was defined as AMI, percutaneous coronary intervention, coronary artery bypass grafting (CABG), or cardiac death occurring within 30 days of initial ED visit. Results: Fourteen patients (7.1%) were diagnosed as 24‐hour AMI and 28 patients (14.3%) experienced 30‐day AO. The optimal cut‐off value for predicting 30‐day AO was >124 μV for ST‐VM and >21.7 μV for QRS‐VD. Patients with either a positive ST‐VM or a positive QRS‐VD had 8.8 times increased odds of AMI (95% confidence interval, CI, 1.9–40.3; P = 0.003); 4.3 times increased odds of 30‐day PTCA/CABG (95% CI 1.3–13.8; P = 0.019); and 3.8 times increased odds of 30‐day AO (95% CI 1.6–9.3; P = 0.003). Conclusions: Baseline ST‐VM and 2‐hour QRS‐VD risk stratifies ED chest pain patients with LVH voltage criteria on the initial 12‐lead ECG.