bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal changes in morphometric and biochemical endpoints in northern pike (Esox lucius), burbot (Lota lota) and slimy sculpin (Cottus cognatus)
Authors: BENNETT PAMELA M. , JANZ DAVID M. 
Published: June 2007

Summary1. Morphometric and biochemical endpoints were used to assess growth and energetics in young‐of‐the‐year (YOY) northern pike (Esox lucius), YOY burbot (Lota lota) and slimy sculpin (Cottus cognatus) collected upstream and downstream of a uranium mining operation in northern Saskatchewan, Canada.2. Water sampled at sites downstream of uranium mining and milling effluent discharge was higher in certain trace metals (arsenic, molybdenum), ions (conductivity, hardness, ammonia and sulphate) and total dissolved solids compared with ecologically similar reference sites.3. Overwinter survival potential was estimated by determining total body lipids and total body triglycerides in fishes collected in late autumn and early spring. Two‐factor anova indicated no site or season differences in total body lipids or triglycerides in YOY northern pike. In spring, burbot collected from the exposure site were higher in total body lipids and triglycerides compared with the previous autumn and compared with fish collected from the reference site. Slimy sculpin from both exposure and reference sites had lower total body lipid and triglyceride content in spring compared with the previous autumn. In addition, sculpin from the exposure site had lower total body lipids and triglycerides in spring compared with fish collected from the reference site.4. Biochemical estimates of fish growth (muscle RNA/DNA ratio and muscle protein concentration) exhibited clear seasonal differences, with consistent decreases in this endpoint for all fish species in spring relative to the previous autumn at both exposure and reference sites.5. Results for total body lipids and triglycerides were inconclusive and inconsistent between species and exposure scenarios. However, all species exhibited a similar seasonal decrease in muscle protein and to a lesser extent, muscle RNA/DNA ratio.
Pleuston communities are buffered from regional flood pulses: the example of ostracods in the Paraná River floodplain, Brazil
Authors: HIGUTI JANET , VELHO LUIZ FELIPE MACHADO , LANSAC‐TÔHA FÁBIO AMODÊO , MARTENS KOEN 
Published: June 2007

Summary1. It is widely acknowledged that sudden, large‐scale flood pulses are drivers of benthic and planktonic biodiversity change in floodplains. The impact of such pulses on pleuston (biotic communities associated with root systems of floating plants) remains to be demonstrated. Here, we investigate the effects of local and regional drivers on seasonal changes in abundance and diversity of ostracod communities in pleuston.2. Temporal and spatial distribution patterns of species richness, abundance, diversity and evenness of ostracods associated with the floating water hyacinth, Eichhornia crassipes, in a lentic environment from the upper Paraná River floodplain, were investigated in relation to local, as well as regional, environmental factors. Ostracods were sampled monthly over an annual cycle (March 2004–February 2005). Twenty‐seven species were found, representing the families Cyprididae, Candonidae, Limnocytheridae and Darwinulidae. Both diversity and abundance of ostracod communities showed seasonal changes, although species turn‐over during the year was limited.3. We tested two hypotheses concerning the causality of these fluctuations: seasonal recruitment and influx of allochthonous ostracods during the flood pulse. Our results indicate that seasonal recruitment is more likely to be the driver of fluctuations in relation to the flood pulse. We postulate that pleuston communities are buffered against possible detrimental effects of flood pulses.
Implementation of a proficiency testing programme for bacterial screening in platelet preparations in Canada
Authors: Mastronardi C. , Martincic I. , Ramírez‐Arcos S. 
Published: June 2007

Background and Objectives  Bacterial screening in apheresis platelet preparations was implemented in March of 2004 by Canadian Blood Services (CBS) using the BacT/ALERT® system. The aim of this study was to develop, validate and implement an in‐house proficiency testing programme to evaluate CBS performance of bacterial screening in platelet preparations.Study Design and Methods  During development of the proficiency testing programme, apheresis platelet preparations were spiked with 101 and 102 colony forming units per ml of Staphylococcus epidermidis, Pseudomonas aeruginosa and Streptococcus pneumoniae. The preparations were stored at 2–8 °C prior to culture bottle inoculation with 4 or 6 ml on Days 7–10 (estimated time from panel preparation to testing at CBS centres). Upon implementation, a combination of four proficiency panel members, including positives and negatives, were distributed to each of the centres that participated in the programme. A survey was conducted with 43 America's Blood Centers to assess whether they screen for bacterial testing in platelet preparations and whether they have implemented a proficiency testing programme.Results  The development of the proficiency testing programme showed that S. epidermidis and P. aeruginosa produced positive results at both concentrations and volumes on Days 7–10 poststorage. Streptococcus pneumoniae did not grow consistently and therefore was not selected for implementation of the programme. Two proficiency testing panel sets have been issued (July 2006 and February 2007) with 14 out of 15 (93%) and 14 out of 14 (100%) of the participant centres meeting the expected results for bacterial screening, respectively. The majority (72%) of the America's Blood Centers that screen for bacterial contamination have not implemented a proficiency testing programme and 94.4% of these centres are interested in developing such a programme.Conclusion  Canadian Blood Services has successfully implemented a proficiency testing programme for bacterial screening in platelet preparations, which will contribute to improving the safety of the platelet supply in Canada.
ROLE OF OESTROGEN IN THE CENTRAL REGULATION OF AUTONOMIC FUNCTION
Authors: Saleh TM , Connell BJ 
Published: June 2007

SUMMARYIn recent years, the role of oestrogen in women's health has been a subject of considerable scientific and popular debate. There is unquestionable evidence that oestrogen has both potent and long‐lasting effects on several vital organ systems, including the cardiovascular system, the autonomic nervous system and, most recently, within the central nervous system itself.The research and medical community continues to debate whether the benefits of oestrogen therapy outweigh the risks in the treatment of the symptoms of menopause, the attenuation of the risk for cardiovascular insults, such as stroke and heart disease, and even the retardation of the progression of Alzheimer's disease.The recent evidence provided by the Heart and Estrogen/Progestin Replacement Study (HERS) II clinical trial suggesting that long‐term exposure to combined oestrogen and progestin in post‐menopausal women who have previously had a heart attack or stroke (for secondary prevention) may actually increase their risk of a subsequent cardiovascular insult has further fuelled the debate. However, there remain considerable gaps in our knowledge with respect to the actual mechanisms by which oestrogen exerts its various beneficial effects at the cellular level for the primary prevention of cardiovascular disease. This information is essential if we are to harness the positive aspects of oestrogen therapy in such a manner as to avoid or minimize the associated risks of increased oestrogen exposure in women who we know, with some certainty, to be at an increased risk of cancers of the uterus, cervix and breast tissue.
EFFECTS OF APOCYNIN AND ETHANOL ON INTRACEREBRAL HAEMORRHAGE‐INDUCED BRAIN INJURY IN RATS
Authors: Titova Elena , Ostrowski Robert P , Sowers Lawrence C , Zhang John H , Tang Jiping 
Published: June 2007

SUMMARY

In the present study, we investigated whether the administration of apocynin, an NADPH oxidase inhibitor, provided brain protection in a rat model of intracerebral haemorrhage (ICH).
Rats were divided into sham, ICH untreated, ICH treated with vehicle (ethanol) and ICH treated with apocynin groups. Intracerebral haemorrhage was induced by collagenase injection. Neurological function, haemorrhage volume and brain oedema were measured 24 h after ICH.
Intracerebral haemorrhage caused significant neurological deficit associated with brain oedema. Apocynin (3, 10 and 30 mg/kg) failed to reduce brain injury after ICH. Low dose ethanol (0.2 g/kg) improved neurological function and reduced brain oedema (ICH‐vehicle vs ICH‐untreated, P < 0.05).
In conclusion, apocynin has no neuroprotective effect when administered intraperitoneally after ICH.
VASODILATATION INDUCED BY SINOMENINE LOWERS BLOOD PRESSURE IN SPONTANEOUSLY HYPERTENSIVE RATS
Authors: Lee Ping‐Ying , Chen Wency , Liu I‐Min , Cheng Juei‐Tang 
Published: June 2007

SUMMARY

Sinomenine is an alkaloid with a wide range of pharmacological actions. In the present study, we investigated the effect of sinomenine on blood pressure and its possible mechanisms of action.
Spontaneously hypertensive rats (SHR) and normotensive Wistar‐Kyoto (WKY) rats were given intraperitoneal injections of sinomenine. At 30 min, 2.5–10 mg/kg sinomenine decreased systolic blood pressure (SBP) in a dose‐dependent manner in SHR, but had no effect on the SBP in WKY rats.
The vascular effect of sinomenine was then examined in aortic rings isolated from Wistar rats. Sinomenine (0.1–10 mmol/L) produced concentration‐dependent relaxation in aortic rings precontracted with phenylephrine (10 nmol/L) or KCl (40 mmol/L). Glibenclamide (1–100 mmol/L), a specific inhibitor of ATP‐sensitive K+ channels attenuated the sinomenine‐induced relaxation, but this effect was not observed when inhibitors of other types of K+ channels were used.
We further investigated the effects of sinomenine on changes in intracellular Ca2+ concentrations ([Ca2+]i) in cultured aortic smooth muscle (A7r5) cells by using the Ca2+‐sensitive dye fura‐2 as an indicator. Sinomenine, over the concentration range 0.1–10 mmol/L, decreased the increases in [Ca2+]i elicited by phenylephrine (1 mmol/L) or KCl (40 mmol/L) in a concentration‐dependent manner. Glibenclamide (1–100 mmol/L) abolished the effects of sinomenine.
In conclusion, sinomenine causes vascular relaxation by opening ATP‐sensitive K+ channels, thus decreasing [Ca2+]i.
NEGATIVE INOTROPIC AND LUSITROPIC EFFECTS OF INTRAVENOUS AMIODARONE IN CONSCIOUS RATS
Authors: Salgado Helio C , Simões Géssica M , Santana Filho Valter J , Dias da Silva Valdo J , Salgado Maria Cristina O , Fazan Rubens 
Published: June 2007

SUMMARY

The acute effect of amiodarone on haemodynamics (mean arterial pressure and heart rate) and ventricular function (+dP/dtmax and –dP/dtmax) was investigated in conscious rats. In addition, the effects of amiodarone on dobutamine stress were determined.
Catheters were inserted in rats into the left ventricle and femoral artery and vein. Three groups of rats received 25 or 50 mg/kg, i.v., amiodarone or vehicle (a 1 : 1 : 8 mixture of Tween 80 : 99.5% ethanol : distilled water), followed by dobutamine (10 µg/kg).
The hypotensive effect of 50 mg/kg amiodarone was combined with marked bradycardia and attenuation of +dP/dtmax and –dP/dtmax. A slight, but significant, hypotension was caused by 25 mg/kg amiodarone, without affecting heart rate, +dP/dtmax and –dP/dtmax. However, although both doses of amiodarone attenuated the tachycardia caused by dobutamine, neither 25 nor 50 mg/kg amiodarone affected the increase in mean arterial pressure or the enhanced response of +dP/dtmax and –dP/dtmax.
In conclusion, amiodarone caused hypotension, bradycardia, negative inotropic (+dP/dtmax) and lusitropic (–dP/dtmax) effects in conscious rats. In addition, amiodarone attenuated the tachycardia without affecting the hypertensive, contractile (+dP/dtmax) and lusitropic (–dP/dtmax) responses to dobutamine stress.
In situ lateral transfer of symbiosis islands results in rapid evolution of diverse competitive strains of mesorhizobia suboptimal in symbiotic nitrogen fixation on the pasture legume Biserrula pelecinus L.
Authors: Nandasena Kemanthi G. , O'Hara Graham W. , Tiwari Ravi P. , Sezmiş Ertuğ , Howieson John G. 
Published: June 2007

SummaryThe multi‐billion dollar asset attributed to symbiotic nitrogen fixation is often threatened by the nodulation of legumes by rhizobia that are ineffective or poorly effective in N2 fixation. This study investigated the development of rhizobial diversity for the pasture legume Biserrula pelecinus L., 6 years after its introduction, and inoculation with Mesorhizobium ciceri bv. biserrulae strain WSM1271, to Western Australia. Molecular fingerprinting of 88 nodule isolates indicated seven were distinctive. Two of these were ineffective while five were poorly effective in N2 fixation on B. pelecinus. Three novel isolates had wider host ranges for nodulation than WSM1271, and four had distinct carbon utilization patterns. Novel isolates were identified as Mesorhizobium sp. using 16S rRNA, dnaK and GSII phylogenies. In a second study, a large number of nodules were collected from commercially grown B. pelecinus from a broader geographical area. These plants were originally inoculated with M. c bv. biserrulae WSM1497 5–6 years prior to isolation of strains for this study. Nearly 50% of isolates from these nodules had distinct molecular fingerprints. At two sites diverse strains dominated nodule occupancy indicating recently evolved strains are highly competitive. All isolates tested were less effective and six were ineffective in N2 fixation. Twelve randomly selected diverse isolates clustered together, based on dnaK sequences, within Mesorhizobium and distantly to M. c bv. biserrulae. All 12 had identical sequences for the symbiosis island insertion region with WSM1497. This study shows the rapid evolution of competitive, yet suboptimal strains for N2 fixation on B. pelecinus following the lateral transfer of a symbiosis island from inoculants to other soil bacteria.
The attribution of attention: 9‐month‐olds’ interpretation of gaze as goal‐directed action
Authors: Johnson Susan C. , Ok Su‐Jeong , Luo Yuyan 
Published: June 2007

Abstract The current study distinguishes between attributions of goal‐directed perception (i.e. attention) and non‐goal‐directed perception to examine 9‐month‐olds’ interpretation of others’ head and eye turns. In a looking time task, 9‐month‐olds encoded the relationship between an actor's head and eye turns and a target object if the head and eye turns were embedded in a sequence of multiple, variable actions with equifinal outcomes, but not otherwise. This evidence supports the claim that infants of this age may attribute perception, at least goal‐directed perception, to others and undermines arguments that gaze‐following at this age consists only of uninterpreted reflexes. The evidence also suggests alternative interpretations of the typical errors infants make in standard gaze‐following procedures. Implications for infants’ understanding of perception and attention in both human and non‐human agents are discussed.
Fourteen‐month‐olds know what others experience only in joint engagement
Authors: Moll Henrike , Carpenter Malinda , Tomasello Michael 
Published: June 2007

AbstractWe investigated how 14‐month‐old infants know what others know. In two studies, an infant played with each of two objects in turn while an experimenter was present. Then the experimenter left the room, and the infant played with a third object with an assistant. The experimenter returned, faced all three objects, and said excitedly ‘Look! Can you give it to me?’ In Study 1, the experimenter experienced each of the first two toys in episodes of joint visual engagement (without manipulation) with the infant. In response to her excited request infants gave the experimenter the object she did not know, thus demonstrating that they knew which ones she knew. In Study 2, infants witnessed the experimenter jointly engage around each of the experienced toys with the assistant, from a third‐person perspective. In response to her request, infants did not give the experimenter the object she had not experienced. In combination with other studies, these results suggest that to know what others have experienced 14‐month‐old infants must do more than just perceive others perceiving something; they must engage with them actively in joint engagement.
TRUST AND VIRTUAL DISTRICTS: EVIDENCE FROM THE MILAN INTERNET EXCHANGE
Authors: Giovannetti Emanuele , Neuhoff Karsten , Spagnolo Giancarlo 
Published: June 2007

ABSTRACTPeering decisions between Internet Service Providers (ISPs) contain substantial non‐measurable aspects requiring trust and informal cooperation among peering partners. We study whether virtual districts are observed between Internet peers. Our empirical analysis of the bilateral peering decisions at the Milan Internet Exchange confirms that these decisions are significantly influenced by: travel time either between ISPs' headquarters or towards the exchange—a proxy for distance, bandwidth—a proxy for size, and European connectivity. Proximity still plays a role in reducing the transaction costs of monitoring and punishing deviant behavior within an industry where trust is essential for Internet universal connectivity.
Mitochondrial and Y Chromosome Diversity in the English‐Speaking Caribbean
Authors: Torres J. Benn , Kittles R. A. , Stone A. C. 
Published: June 2007

SummaryThe transatlantic slave trade lasted over three centuries and represents one of the largest forced migrations in human history. The biological repercussions are not well understood especially in African‐Caribbean populations. This paper explores the effects of the forced migration, isolation, and admixture on genetic diversity using mitochondrial and Y chromosome markers for 501 individuals from Dominica, Grenada, Jamaica, St. Kitts, St. Lucia, St. Thomas, St. Vincent, and Trinidad. Genetic diversity and population genetic structure analyses of mitochondrial data and Y chromosome data indicate that there was no post‐migration loss in genetic diversity in the African derived lineages. Genetic structure was observed between the islands for both genetic systems. This may be due to isolation, differences in the number and source of Africans imported, depopulation of indigenous populations, and/or differences in colonization history. Nearly 10% of the individuals belonged to a non‐African mitochondrial haplogroup. In contrast, Y chromosome admixture estimates showed that there was nearly 30% European contribution to these Caribbean populations. This study sheds light on the history of Africans in the Americas as well as contributing to our understanding of the nature and extent of diversity within the African Diaspora.
Characterization, multiplex conditions, and cross‐species utility of tetranucleotide microsatellite loci for Blanchard's cricket frog (Acris crepitans blanchardi)
Authors: BEAUCLERC KAELA B. , JOHNSON BOB , WHITE BRADLEY N. 
Published: June 2007

AbstractWe have isolated and characterized 17 tetranucleotide microsatellite loci for Blanchard's cricket frog (Acris crepitans blanchardi), an anuran common in the central USA. Sixteen loci were organized into four multiplex amplification reactions. These loci were highly polymorphic when screened in 55 individuals from two distant populations, with 11–48 alleles per locus (average = 24.8). Observed and expected heterozygosities ranged from 0.18 to 0.97 and from 0.17 to 0.96, respectively. Nine loci were also polymorphic in Acris crepitans crepitans, with seven polymorphic in Acris gryllus. Five loci amplified in all three taxa. These loci will be useful for population‐ and species‐level investigations of this widespread group.
Nondestructive DNA extraction from blackflies (Diptera: Simuliidae): retaining voucher specimens for DNA barcoding projects
Authors: HUNTER STEPHANIE J. , GOODALL TIM I. , WALSH KERRY A. , OWEN RICHARD , DAY JOHN C. 
Published: June 2007

AbstractA nondestructive, chemical‐free method is presented for the extraction of DNA from small insects. Blackflies were submerged in sterile, distilled water and sonicated for varying lengths of time to provide DNA which was assessed in terms of quantity, purity and amplification efficiency. A verified DNA barcode was produced from DNA extracted from blackfly larvae, pupae and adult specimens. A 60‐second sonication period was found to release the highest quality and quantity of DNA although the amplification efficiency was found to be similar regardless of sonication time. Overall, a 66% amplification efficiency was observed. Examination of post‐sonicated material confirmed retention of morphological characters. Sonication was found to be a reliable DNA extraction approach for barcoding, providing sufficient quality template for polymerase chain reaction amplification as well as retaining the voucher specimen for post‐barcoding morphological evaluation.
Low rates of hydrogen peroxide production by isolated heart mitochondria associate with long maximum lifespan in vertebrate homeotherms
Authors: Lambert Adrian J. , Boysen Helen M. , Buckingham Julie A. , Yang Ting , Podlutsky Andrej , Austad Steven N. , Kunz Thomas H. , Buffenstein Rochelle , Brand Martin D. 
Published: June 2007

SummaryAn inverse correlation between free radical production by isolated mitochondria and longevity in homeotherms has been reported, but previous comparative studies ignored possible confounding effects of body mass and phylogeny. We investigated this correlation by comparing rates of hydrogen peroxide (H2O2) production by heart mitochondria isolated from groups or pairs of species selected to have very different maximum lifespans but similar body masses (small mammals, medium‐sized mammals, birds). During succinate oxidation, H2O2production rates were generally lower in the longer‐lived species; the differences arose at complex I of the electron transport chain during reverse electron transport. Additional data were obtained from large species and the final dataset comprised mouse, rat, white‐footed mouse, naked mole‐rat, Damara mole‐rat, guinea pig, baboon, little brown bat, Brazilian free‐tailed bat, ox, pigeon and quail. In this dataset, maximum lifespan was negatively correlated with H2O2production at complex I during reverse electron transport. Analysis of residual maximum lifespan and residual H2O2production revealed that this correlation was even more significant after correction for effects of body mass. To remove effects of phylogeny, independent phylogenetic contrasts were obtained from the residuals. These revealed an inverse association between maximum lifespan and H2O2production that was significant by sign test, but fell short of significance by regression analysis. These findings indicate that enhanced longevity may be causally associated with low free radical production by mitochondria across species over two classes of vertebrate homeotherms.