bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic variation in pea (Pisum sativum L.) demonstrates the importance of root but not shoot C/N ratios in the control of plant morphology and reveals a unique relationship between shoot length and nodulation intensity
Authors: LUDIDI NDIKO N. , PELLNY TILL K. , KIDDLE GUY , DUTILLEUL CHRISTELLE , GROTEN KARIN , VAN HEERDEN PHILIPPUS D. R. , DUTT SOM , POWERS STEPHEN J. , RÖMER PETER , FOYER CHRISTINE H.
Published: July 2007

Nodule numbers are regulated through systemic auto‐regulatory signals produced by shoots and roots. The relative effects of shoot and root genotype on nodule numbers together with relationships to organ biomass, carbon (C) and nitrogen (N) status, and related parameters were measured in pea (Pisum sativum) exploiting natural genetic variation in maturity and apparent nodulation intensity. Reciprocal grafting experiments between the early (Athos), intermediate (Phönix) and late (S00182) maturity phenotypes were performed and Pearson's correlation coefficients for the parameters were calculated. No significant correlations were found between shoot C/N ratios and plant morphology parameters, but the root C/N ratio showed a strong correlation with root fresh and dry weights as well as with shoot fresh weight with less significant interactions with leaf number. Hence, the root C/N ratio rather than shoot C/N had a predominant influence on plant morphology when pea plants are grown under conditions of symbiotic nitrogen supply. The only phenotypic characteristic that showed a statistically significant correlation with nodulation intensity was shoot length, which accounted for 68.5% of the variation. A strong linear relationship was demonstrated between shoot length and nodule numbers. Hence, pea nodule numbers are controlled by factors related to shoot extension, but not by shoot or root biomass accumulation, total C or total N. The relationship between shoot length and nodule numbers persisted under field conditions. These results suggest that stem height could be used as a breeding marker for the selection of pea cultivars with high nodule numbers and high seed N contents.
Increase in respiratory cost at high growth temperature is attributed to high protein turnover cost in Petunia × hybrida petals
Authors: HACHIYA TAKUSHI , TERASHIMA ICHIRO , NOGUCHI KO
Published: July 2007

It is widely believed that turnover of nitrogenous (N) compounds (especially proteins) incurs a high respiratory cost. Thus, if protein turnover costs change with temperature, this would influence the dependence of respiration rate on growth temperature. Here, we examined the extent to which protein turnover cost explained differences in N‐utilization costs (nitrate uptake/reduction, ammonium assimilation, amino acid and protein syntheses, protein turnover and amino acid export) and in respiration rate with changes in growth temperature. By measurements and literature data, we evaluated each N‐utilization cost in Petunia × hybrida petals grown at 20, 25 or 35 °C throughout their whole lifespans. Protein turnover cost accounted for 73% of the integrated N‐utilization cost on a whole‐petal basis at 35 °C. The difference in this cost on a dry weight basis between 25 and 35 °C accounted for 75% of the difference in N‐utilization cost and 45% of the difference in respiratory cost. The cost of nitrate uptake/reduction was high at low growth temperatures. We concluded that respiratory cost in petals was strongly influenced by protein turnover and nitrate uptake/reduction, and on the shoot basis, C investment in biomass was highest at 25 °C.
The functional significance of C3–C4intermediate traits inHeliotropiumL. (Boraginaceae): gas exchange perspectives
Authors: VOGAN PATRICK J. , FROHLICH MICHAEL W. , SAGE ROWAN F.
Published: July 2007

We demonstrate for the first time the presence of species exhibiting C3–C4intermediacy inHeliotropium(sensu lato), a genus with over 100 C3and 150 C4species. CO2compensation points (Γ) and photosynthetic water‐use efficiencies (WUEs) were intermediate between C3and C4values in three species ofHeliotropium:Heliotropium convolvulaceum(Γ = 20 µmol CO2 mol−1air),Heliotropium racemosum(Γ = 22 µmol mol−1) andHeliotropium greggii(Γ = 17 µmol mol−1).Heliotropium procumbensmay also be a weak C3–C4intermediate based on a slight reduction inΓ(48.5 µmol CO2 mol−1) compared to C3Heliotropiumspecies (52–60 µmol mol−1). The intermediate speciesH. convolvulaceum,H. greggiiandH. racemosumexhibited over 50% enhancement of net CO2assimilation rates at low CO2levels (200–300 µmol mol−1); however, no significant differences in stomatal conductance were observed between the C3and C3–C4species. We also assessed the response ofΓto variation in O2concentration for these species.Heliotropium convolvulaceum,H. greggiiandH. racemosumexhibited similar responses ofΓto O2with response slopes that were intermediate between the responses of C3and C4species below 210 mmol O2 mol−1air. The presence of multiple species displaying C3–C4intermediate traits indicates thatHeliotropiumcould be a valuable new model for studying the evolutionary transition from C3to C4photosynthesis.
To what extent do current and projected increases in surface ozone affect photosynthesis and stomatal conductance of trees? A meta‐analytic review of the last 3 decades of experiments
Authors: WITTIG VICTORIA E. , AINSWORTH ELIZABETH A. , LONG STEPHEN P.
Published: July 2007

The surface concentration of ozone ([O3]) has risen from less than 10 ppb prior to the industrial revolution to a day‐time mean concentration of approximately 40 ppb over much of the northern temperate zone. If current global emission trends continue, surface [O3] is projected to rise a further 50% over this century, with larger increases in many locations including Northern Hemisphere forests. This review uses statistical meta‐analysis to determine mean effects, and their confidence limits, of both the current and projected elevations of [O3] on light‐saturated photosynthetic CO2 uptake (Asat) and stomatal conductance (gs) in trees. In total, 348 measurements of Asat from 61 studies and 266 measures of gs from 55 studies were reviewed. Results suggested that the elevation of [O3] that has occurred since the industrial revolution is depressing Asat and gs by 11% (CI 9–13%) and 13% (CI 11–15%), respectively, where CI is the 95% confidence interval. In contrast to angiosperms, gymnosperms were not significantly affected. Both drought and elevated [CO2] significantly decreased the effect of ambient [O3]. Younger trees (<4 years) were affected less than older trees. Elevation of [O3] above current levels caused progressively larger losses of Asat and gs, including gymnosperms. Results are consistent with the expectation that damage to photosynthesis depends on the cumulative uptake of ozone (O3) into the leaf. Thus, factors that lower gs lessen damage. Where both gs and [O3] were recorded, an overall decline in Asat of 0.21% per mmol m−2 of estimated cumulative O3 uptake was calculated. These findings suggest that rising [O3], an often overlooked aspect of global atmospheric change, is progressively depressing the ability of temperate and boreal forests to assimilate carbon and transfer water vapour to the atmosphere, with significant potential effects on terrestrial carbon sinks and regional hydrologies.
Phylogeny of the bees of the family Apidae based on larval characters with focus on the origin of cleptoparasitism (Hymenoptera: Apiformes)
Authors: STRAKA JAKUB , BOGUSCH PETR
Published: July 2007

AbstractFifty‐four genera of the bee family Apidae comprising almost all tribes were analysed based on 77 traditional and one new character of the mature larvae. Nine, especially cleptoparasitic species, were newly added. Analyses were performed by maximum parsimony and Bayesian inference. Trees inferred from the analysis of the complete dataset were rooted by taxa from the families Melittidae and Megachilidae. Unrooted trees inferred from the analysis of the partial dataset (excluding outgroup taxa) are also presented to preclude possible negative effects of the outgroup on the topology of the ingroup. Only the subfamily Nomadinae was statistically well supported. The monophyly of the subfamilies Xylocopinae and Apinae was not topologically recovered. The monophyly of the tribe Tetrapediini was supported, and this tribe was found to be related to xylocopine taxa. At the very least, larval morphology suggests thatTetrapediais not a member of the subfamily Apinae. Our analyses support the monophyly of the Eucerine line (Emphorini, Eucerini, Exomalopsini, Tapinotaspidini) and of the Apine line (Anthophorini, Apini, Bombini, Centridini, Euglossini, Meliponini). All analyses support the monophyly of totally cleptoparasitic tribes of the subfamily Apinae. We named this group the Melectine line (Ericrocidini, Isepeolini, Melectini, Osirini, Protepeolini, Rhathymini). In previous studies all these cleptoparasitic tribes were considered independent evolutionary lineages. Our results suggest that their similarities with hosts in morphology and pattern are probably the result of convergence and host–parasite co‐evolution than phylogenetic affinity. According to the present analysis, the cleptoparasitism has evolved independently only six times within the family Apidae.
Winter at the alpine timberline causes complex within‐tree patterns of water potential and embolism in Picea abies
Authors: Mayr Stefan , Charra‐Vaskou Katline
Published: July 2007

Winter temperatures at the alpine timberline cause ice formation in the xylem of conifers blocking water uptake as well as water shifts within the axes system. This amplifies drought stress that, in combination with freeze–thaw events, causes embolism. This study focussed on within‐tree patterns of water potential (ψ) and embolism in Norway spruce [Picea abies (L.) Karst.]. At five sampling dates in midwinter, ψ was determined at numerous positions in the crown of three trees, and at the end of March, the extent of embolism in representative sections of the axes system was analysed. Until 14 March, mean ψ decreased to −3.77 ± 0.11 MPa with less negative ψ in exposed crown parts. On 30 March, ψ was −1.60 ± 0.06 MPa, while loss of conductivity reached up to 100%. Conductivity losses increased with exposition and were highest in the smallest tree. The observed complex within‐tree patterns of ψ and embolism were caused by ice blockages and differences in stress intensities within the xylem. High conductivity losses despite moderate ψ in exposed crown parts indicated freeze–thaw events to be a major inducer of winter embolism. Tree size may play a critical role for winter water relations as trees profit from water stored in the stem and in crown parts below the snow cover.
Separating the effects of hypobaria and hypoxia on lettuce: growth and gas exchange
Authors: He Chuanjiu , Davies Fred T. , Lacey Ronald E.
Published: July 2007

The objectives of this research were to determine the influence of hypobaria (reduced atmospheric pressure) and reduced partial pressure of oxygen (pO2) [hypoxia] on carbon dioxide (CO2) assimilation (CA), dark‐period respiration (DPR) and growth of lettuce (Lactuca sativa L. cv. Buttercrunch). Lettuce plants were grown under variable total gas pressures [25 and 101 kPa (ambient)] at 6, 12 or 21 kPa pO2 (approximately the partial pressure in air at normal pressure). Growth of lettuce was comparable between ambient and low total pressure but lower at 6 kPa pO2 (hypoxic) than at 12 or 21 kPa pO2. The specific leaf area of 6 kPa pO2 plants was lower, indicating thicker leaves associated with hypoxia. Roots were most sensitive to hypoxia, with a 50–70% growth reduction. Leaf chlorophyll levels were greater at low than at ambient pressure. Hypobaria and hypoxia did not affect plant water relations. While hypobaria did not adversely affect plant growth or CA, hypoxia did. There was comparable CA and a lower DPR in low than in ambient total pressure plants under non‐limiting CO2 levels (100 Pa pCO2, nearly three‐fold that in normal air). The CA/DPR ratio was higher at low than at ambient total pressure, particularly at 6 kPa pO2– indicating a greater efficiency of CA/DPR in low‐pressure plants. There was generally no significant interaction between hypoxia and hypobaria. We conclude that lettuce can be grown under subambient pressure (≅25% of normal earth ambient total pressure) without adverse effects on plant growth or gas exchange. Furthermore, hypobaric plants were more resistant to hypoxic conditions that reduced gas exchange and plant growth.
Voltage‐dependent action potentials in Arabidopsis thaliana
Authors: Favre Patrick , Agosti Robert Degli
Published: July 2007

Voltage‐elicited action potentials (APs) have been reproducibly obtained in Arabidopsis thaliana ecotype col. Excitations pulses (voltage–duration: V–t) were given in the 0‐ to 18‐V and 0‐ to 35‐s ranges, respectively, by two galvanically isolated Pt/Ir small wires inserted trough the main vein in the distal part of the leaf. Conventional liquid junction Ag/AgCl electrodes were placed at the zone between leaf/petiole (e1) and a second one on the petiole, near the central axis of the rosette (e2). A typical hyperbolic V–t relationship was obtained. The most excitable plants did have a chronaxy of 0.1 s and a rheobase of 2 V. Although the amplitude of the APs was highly variable (range 10–80 mV), it was related neither to the intensity nor to the duration of the stimulation pulse: the phenomenon is a typical all‐or‐none response. The APs were moving away from the excitation zone and could successively be detected at e1 and then at e2: their propagation speed was 1.15 ± 0.26 mm s−1. The absolute refractory period was approximately 20 min and the relative one approximately 80 min. The reproducibility of the voltage elicitation was in A. thaliana col ecotype 91%, with 83% of the APs propagating from the leaf to the petiole. In the Wassilewskija ecotype, 45% of the plants were responsive, with 78% of APs transmitted (propagation speed was 0.76 ± 0.17 mm s−1), whereas in the Lansberg erecta ecotype none of the plant tested elicited a voltage‐dependent AP.
Red to far‐red ratio correction in plant growth chambers – growth responses and influence of thermal load on garden pea
Authors: Cummings Ian G. , Reid James B. , Koutoulis Anthony
Published: July 2007

Plant growth chambers are commonly used to minimize environmental variation but the light sources used vary considerably from natural light and from each other. Incandescent globes are often used to add more far‐red light, with the aim of producing a more natural red to far‐red ratio (R:FR), but also add to thermal load. High‐intensity discharge lamps are often used to produce higher irradiances, more akin to natural light, but the thermal implications are rarely considered because air temperature is controlled. This paper examines the spectral properties and thermal implications of growth chamber light sources and takes a whole‐plant physiology approach, by examining growth responses of a photoperiodic pea line (Pisum sativum L. cv. Torsdag) in the same growth chamber type under different light sources – in essence using plants to study the controlled environments rather than vice‐versa. High R:FR delayed flowering and inhibited internode extension in pea. However, the addition of far‐red‐rich incandescent globes in the proportions provided in the growth chambers (400–500 W) did little to reduce R:FR, did not induce earlier flowering and actually further inhibited internode length. Leaflet size and yield were significantly reduced. While air temperature was maintained at 20°C in all experiments, radiant temperature was significantly higher under high irradiance and/or with incandescent added, and soil temperatures were elevated. Growth responses under these lights were similar to the effect caused by elevating the air temperature. An alternative method of controlling R:FR, without thermal load implications, using light‐emitting diodes is described.
Evaluating nurse prescribing behaviour using constipation as a case study
Authors: Davis Kathy , Drennan Vari
Published: July 2007

Non‐medical nurse prescribing in the UK continues to evolve with new legislative frameworks. Studies evaluating patterns of prescribing by nurses remain scarce. This secondary data analysis of national prescribing data investigated the prescribing behaviours of community‐based nurses and general practitioners (GPs), using constipation as a case study. Currently, 37 683 registered nurses, midwives and health visitors are qualified to independently prescribe in the UK; however, only 16.6% of nurses prescribed items for constipation. Prescribing practices differed between nurses employed by primary care trusts (PCTs) and general practice, between nurses and GPs, and across regions. PCT‐employed nurses undertook 83% of nurse prescribing although activity increased steadily among general practice‐employed nurses. Pharmacological treatment choices differed between nurses and GPs. Over 60% of all nurses predominantly prescribed from one class of laxative compared with a wider range prescribed by GPs. The extent, impact and outcomes of medical prescribing need further study.
Body composition of children with chronic and end‐stage renal failure
Authors: Nydegger Andreas , Strauss Boyd JG , Heine Ralf G , Asmaningsih Ninik , Jones Colin L , Bines Julie E
Published: July 2007

Aim:  Protein energy malnutrition is common in children with chronic renal failure (CRF) and may negatively impact on clinical outcome. Although the aetiology of malnutrition is multifactorial, descriptive information on body composition may guide nutritional interventions aimed at optimising nutritional status.

Methods:  This prospective cohort study in children with CRF was conducted from April 1999 to November 2000. Patients were categorised according to their glomerular filtration rate (GFR) into CRF and end‐stage renal failure (ESRF). Body composition was assessed based on anthropometry, total body potassium (TBK), total body protein (TBP) and dual X‐ray absorptiometry (DEXA).

Results:  Fifteen patients (10 male, 5 female; mean age: 13.4 ± 4.3 years) were studied, including eight patients with CRF (mean GFR: 17.0 ± 7.2 mL/min/1.73 m2) and seven patients with ESRF (mean GFR: 6.4 ± 1.7 mL/min/1.73 m2). Patients in both groups (n = 15) had deficits in height and TBP (mean z‐score height‐for‐age: −1.19 ± 1.05, P < 0.01; mean z‐score TBP: −0.71 ± 0.71, P < 0.05). There were no significant differences in weight, height, fat‐free mass, TBK and TBP between patients with CRF and ESRF.

Conclusions:  Linear growth impairment and decreased TBP are common in children with chronic and ESRF. TBK and DEXA may underestimate the degree of malnutrition in these patients.
Estimating inspired oxygen concentration delivered by nasal prongs in children with bronchiolitis
Authors: Sung Valerie , Massie John , Hochmann Mark A , Carlin John B , Jamsen Kris , Robertson Colin F
Published: July 2007

Aims:  The inspired oxygen concentration (FiO2) is an important criterion for assessing the severity of bronchiolitis. Oxygen delivery by nasal prongs is a measure of oxygen flow, but not FiO2. We aimed to determine whether FiO2 of oxygen delivered by nasal prongs could be predicted from nasal flow by relating arterial oxygen concentrations achieved with prongs to those achieved via head box in children with bronchiolitis.

Methods:  This is a pilot study conducted at a tertiary referral paediatric hospital. We studied hospitalised children less than 24 months old requiring supplemental oxygen because of bronchiolitis, an acute viral lower respiratory tract infection. Children admitted to the intensive care unit, and those with congenital cardiac disease or recent bronchodilator use were excluded. Subjects were studied in nasal prong, then head box oxygen. Arterial oxygen concentration was measured by a transcutaneous probe (tcPO2). Oxygen flows by nasal prongs and FiO2 by head box were adjusted to achieve similar tcPO2 readings. FiO2 values were plotted against oxygen flow rates based on matching tcPO2.

Results:  We recorded tcPO2 across a satisfactory range of values in eight children. TcPO2 increased with increasing FiO2 and nasal oxygen flow, but at variable rates between subjects. FiO2 increased with increasing nasal oxygen flow, but this relationship was highly variable.

Conclusions:  In this study, it was not possible to estimate FiO2 reliably from nasal oxygen flow rates in children with bronchiolitis. Nasal prong oxygen flow rates should be used with caution when assessing the severity of bronchiolitis in children.
Enhanced Aquaporin‐4 immunoreactivity in sporadic Creutzfeldt‐Jakob disease
Authors: Iwasaki Yasushi , Mimuro Maya , Yoshida Mari , Hashizume Yoshio , Ito Masumi , Kitamoto Tetsuyuki , Wakayama Yoshihiro , Sobue Gen
Published: July 2007

Aquaporin‐4 (AQP‐4) is a water channel protein located on the plasma membrane of astrocytes and is regulated under various conditions. In the present study, a series of brains with sporadic Creutzfeldt‐Jakob disease (sCJD) were investigated to determine the possible contribution of AQP‐4 in the development of sCJD pathology. Six cases of subacute spongiform encephalopathy (SSE) and four cases of panencephalopathic (PE)‐type sCJD were included. Increased AQP‐4 immunoreactivity compared to that in controls was observed in all sCJD patients, particularly in the cerebral neocortex and cerebellar cortex. AQP‐4 immunoreactivity was present in the cell bodies and processes of protoplasmic astrocytes in SSE and around cell bodies and processes of hypertrophic astrocytes in PE‐type sCJD. Analysis of serial sections showed the development of sCJD pathology, particularly in neocortical lesions, as follows: PrP deposition; spongiform change and gliosis; enhanced staining for AQP‐4; hypertrophic astrocytosis; and neuronal loss and tissue rarefaction. Strong AQP‐4 immunoreactivity was present in burnt‐out lesions such as those of status spongiosus. These results indicate that increased AQP‐4 expression in sCJD is an early pathologic event and appears to remain until the late disease stage. We suggest that increased expression of AQP‐4 is a pathologic feature of sCJD.
Dysembryoplastic neuroepithelial tumor (DNT)‐like oligodendrogliomas or DNTs evolving into oligodendrogliomas: Two illustrative cases
Authors: Gonzales Michael , Dale Susan , Susman Marleen , Nolan Prudence , Ng Wai Hoe , Maixner Wirginia , Laidlaw John
Published: July 2007

A review of dysembryoplastic neuroepithelial tumors (DNTs) in 14 patients over a 12‐year period revealed four patients re‐operated because of changes on magnetic resonance imaging (MRI) suggesting tumor recurrence or progression. In three of these, the histological features were identical to the initial DNT. In the fourth patient, persistent DNT was surrounded by WHO grade 2 oligoastrocytoma. In one of the other 10 patients, WHO grade 2 oligodendroglioma was present in white matter deep to and completely separate from a cortically based DNT. Fluorescence in situ hybridization showed codeletion of 1p and 19q in both the DNT and oligodendroglioma and oligoastrocytoma components. Deletions were not identified in any other tumor. Our findings corroborate other studies that 1p and 19q deletions are uncommon in DNT. These two unusual tumors also raise the possibility that rare DNTs may evolve into oligodendroglioma or oligoastrocytoma. DNTs with this altered biology can be identified by 1p and 19q deletion analysis.
RASSF1A promoter is highly methylated in primitive neuroectodermal tumors of the central nervous system
Authors: Inda María‐del‐Mar , Castresana Javier S
Published: July 2007

Although cancer is rare in children, primary brain tumors constitute the most frequent location of solid tumors in childhood. Primitive neuroectodermal tumors (PNET) of the central nervous system can be divided into infratentorial PNET or medulloblastoma (MB), and supratentorial (sPNET) tumors. Although MB and sPNET are histologically similar, clinical evolution differs, sPNET being more aggressive than MB. Some studies have suggested that MB and sPNET present different molecular genetic aberrations. The RASSF1A (Ras Association Domain Family Protein 1) gene, located at 3p21.3, is highly methylated in multiple primary tumor samples, including neuroblastoma. In order to define whether there are genetic differences in the methylation frequency of RASSF1A between MB and sPNET, we analyzed 32 PNET paraffin‐embedded samples (23 MB and 9 sPNET) by methylation specific polymerase chain reaction (MSP). We also analyzed RASSF1A expression by reverse transcription polymerase chain reaction in five PNET cell lines. All PNET cell lines showed lack of RASSF1A expression that was correlated with RASSF1A promoter hypermethylation. RASSF1A methylation was detected in 19 of 21 MB cases (91%) and in five of six sPNET samples (83%). Although the methylation frequency found in MB was slightly higher than in sPNET, no statistical differences were found for the RASSF1A hypermethylation frequency (P > 0.05) presented at MB versus sPNET. Therefore, the inactivation of the RASSF1A gene seems to be an important step in the tumorigenesis of PNET of the central nervous sytem. More studies should be performed in order to determine genetic differences between MB and sPNET.
Decreased neuronal nitric oxide synthase expression and cell migration in the peri‐infarction after focal cerebral ischemia in rats
Authors: Zhang Pengbo , Liu Yong , Li Jie , Kang Qianyan , Tian Yingfang , Chen Xinlin , Zhao Jianjun , Shi Qindong , Song Tusheng
Published: July 2007

Neuronal nitric oxide synthase (nNOS) regulates neurogenesis in the normal developing brain, but the role of nNOS in neurogenesis of the adult ischemic brain remains unclear. The aim of this study was to investigate the temporal and spatial relationship between cell migration from the ependymal/subventricular zone (SVZ) to peri‐infarction and nNOS expression in the rat. Ependymal/subventricular zone cells were prelabeled with fluorescence dye DiI. Focal cerebral ischemia was induced by occlusion of the left middle cerebral artery. At 1, 3, 7, 14 and 21 days after ischemia, the rats were killed in order to determine the number of migrating cells, the colocalization of DiI and nNOS as well as nNOS quantity in specific regions. Compared to non‐ischemic control and 1 day post‐ischemia, the number of DiI‐labeled cells in the selected regions increased at 3 days and peaked 14 days following ischemia. During 3–7 days post‐ischemia, none of the migrating cells expressed nNOS and decreased nNOS expression was observed in the regions where migrating cells passed through. These results suggest the possible association between ependymal/SVZ cell migration and decreased nNOS expression within the areas including the migrating routes towards the peri‐infarction.
Clostridium difficile‐associated diarrhoea
Authors: Elliott B. , Chang B. J. , Golledge C. L. , Riley T. V.
Published: July 2007

Clostridium difficile is an important nosocomial pathogen and the most frequently diagnosed cause of infectious hospital‐acquired diarrhoea. Toxigenic strains usually produce toxin A and toxin B, which are the primary virulence factors of C. difficile. Some recently described strains produce an additional toxin, an adenosine‐diphosphate ribosyltransferase known as binary toxin, the role of which in pathogenicity is unknown. There has been concern about the emergence of a hypervirulent fluoroquinolone‐resistant strain of C. difficile in North America and Europe. The use of fluoroquinolone antimicrobials appears to be acting as a selective pressure in the emergence of this strain. In this review, we describe the current state of knowledge about C. difficile as a cause of diarrhoeal illness.
Insertion characteristics, sealing pressure and fiberoptic positioning of CobraPLA in children
Authors: PASSARIELLO MAURIZIO , ALMENRADER NICOLE , COCCETTI BRUNO , HAIBERGER ROBERTA , PIETROPAOLI PAOLO
Published: July 2007

Background:  The CobraPLATM is a new supraglottic airway device designed for the use in spontaneously breathing and mechanically ventilated patients. In adults it has been found as effective as the LMA, but with better sealing qualities. The aim of the present study was to evaluate fit and sealing characteristics of CobraPLA size 1.5 and 2 in mechanically ventilated children.

Methods:  Forty children, ASA I/II, aged 1–10 years, weighing 10–35 kg were scheduled for minor surgical procedures. The number of attempts for insertion and fiberoptic positioning of the CobraPLA was assessed. After muscle relaxation had been achieved, airway sealing pressure was measured by gradually increasing maximum inspiratory pressure to a maximum of 30 cmH2O.

Results:  Insertion of CobraPLA was successful at the first attempt in 90% of patients. The vocal cords were visualized in 90% of patients (grade 0: 2.5%, grade 1: 7.5%, grade 2: 30%, grade 3: 15%, grade 4: 45%). Median sealing pressure was 20.0 ± 6.0 cmH2O. In 21% of patients gastric insufflation was observed at a peak inspiratory pressure of 20 cmH2O or below.

Conclusions:  The CobraPLA was found to have easy insertion characteristics and good anatomical fitting in children between 10 and 35 kg.

If positive pressure ventilation with CobraPLA size 1.5 and 2.0 is required, peak inspiratory pressure should be kept below the leak pressure and the abdomen closely monitored for signs of gastric insufflation.
Evidence based medicine methods (part 2): extension into the clinical area
Authors: MACKINNON RALPH JAMES
Published: July 2007

The principles of evidence‐based medicine (EBM) applied to pediatric anesthesia could result in a potent educational tool. At present there is a limited structured evidence base to pediatric anesthesia. However, the wide array of pediatric anesthetic research and clinical practice itself are well suited to the principles of EBM. Best evidence topics could be considered the starting point for a potentially extremely useful evidence‐based pediatric anesthesia database.
Changes in respiratory and hemodynamic parameters during low‐dose propofol sedation in combination with regional anesthesia for herniorrhaphy and genitourinary surgery in children
Authors: ZANABONI SILVIO , KRAUSS BARUCH , BUSCAGLIA RAFFAELLA , MONTAGNINI CLAUDIA , GRATAROLA ANGELO , GUALINO JENNY , COLOMBO ROBERTO , CORTE FRANCESCO DELLA
Published: July 2007

Background:  Spontaneous vs mechanical ventilation during propofol sedation has been a subject of debate. We evaluated the safety of low‐dose propofol sedation as an adjunct to regional anesthesia during herniorrhaphy and genitourinary surgery in infants and children.

Methods:  The study was conducted in a prospective, nonrandomized manner using a consecutive sample of 62 American Society of Anesthesiologists physical status class I patients between 5 months to 11 years of age in the surgery unit of an urban University Hospital. Propofol sedation (4–8 mg·kg−1·h−1 continuous infusion) was used with regional anesthesia (caudal, ilioinguinal/iliohypogastric nerve or penile block with 0.2–0.375% ropivacaine). All children were spontaneously breathing without an anesthesia circuit. Respiratory and hemodynamic parameters were continuously recorded on all patients. One‐way analysis of variance (anova) for repeated measurements was used to analyze changes in respiratory and hemodynamic parameters during the procedure.

Results:  Spontaneous ventilation was maintained in all patients with minimal changes in hemodynamic parameters. Heart rate, mean arterial pressure, and PECO2 remained stable throughout the study period: 23/62 (37%) patients exhibited signs of developing intrinsic endexpiratory pressure (PEEPi) or the presence of PEEPi because of progressive reduction of expiratory time.

Conclusions:  Low‐dose propofol sedation in combination with regional anesthesia for elective herniorrhaphy and genitourinary surgery in children maintains spontaneous ventilation and has minimal effects on hemodynamic parameters for sedation lasting <1 h. The presence of PEEPi is a relative contraindication to the use of this regimen in children with asthma or history of upper airway infections.
Glycated haemoglobin as a predictor for metabolic syndrome in non‐diabetic Korean adults
Authors: Sung K. C. , Rhee E. J.
Published: July 2007

Aims  With increasing prevalence of diabetes mellitus and metabolic syndrome (MS), the importance of early detection of insulin resistance is emphasized. However, a simple and practical method of measurement is not readily available. Therefore, we examined the sensitivity and specificity of HbA1c for predicting impaired fasting glucose (IFG) and MS and its association with cardiovascular risk factors, particularly in the normal range of HbA1c levels in non‐diabetic Korean subjects.

Methods  In 40 155 participants (median age 40 years) participating in a medical check‐up programme, analysis of the distribution of HbA1c and its association with various cardiovascular risk factors was performed. In 22 465 selected participants, an analysis was conducted of the ability of HbA1c to predict MS and IFG. Anthropometric measurements were made in all subjects and fasting glucose, lipid profiles and HbA1c were measured. The presence of MS was defined according to the definitions of the Adult Treatment Panel III (ATP III) guideline and the new International Diabetes Federation (IDF) guideline. Patients with diabetes were excluded from the study.

Results  The incidence of MS was 12.2% according to ATP III criteria and 7.6% according to IDF criteria. When subjects were grouped by quartile of HbA1c, cardiovascular risk factors significantly increased as the HbA1c increased. An HbA1c of 5.45% predicted the presence of MS (ATP III: sensitivity/specificity 57.4/64.3%, area under the curve 64.8%; IDF: sensitivity 60.2/63.4%, area under the curve 66.1%) and fasting blood glucose ≥ 5.6 mmol/l (sensitivity/specificity 53.7/70%, area under the curve 66.1%). When the analyses were done separately by gender, female subjects showed higher cut‐off of HbA1c for the prediction of MS (5.55% for both ATP III and IDF criteria).

Conclusions  HbA1c increased as cardiovascular risk factors increased and HbA1c of 5.45% predicted the presence of MS. HbA1c might be a predictive measure of IFG and MS, and also cardiovascular risk factors in the Korean population.
The Timing of Middle‐Childhood Peer Rejection and Friendship: Linking Early Behavior to Early‐Adolescent Adjustment
Authors: Pedersen Sara , Vitaro Frank , Barker Edward D. , Borge Anne I. H.
Published: July 2007

This study used a sample of 551 children surveyed yearly from ages 6 to 13 to examine the longitudinal associations among early behavior, middle‐childhood peer rejection and friendedness, and early‐adolescent depressive symptoms, loneliness, and delinquency. The study tested a sequential mediation hypothesis in which (a) behavior problems in the early school years are associated with middle‐childhood peer rejection and (b) rejection, in turn, leads to lower friendedness and subsequently higher adolescent internalizing—but not externalizing—problems. Results supported this sequential mediation model for internalizing outcomes and revealed an additional path from early disruptiveness to loneliness via peer rejection alone. No evidence of sequential mediation was observed for delinquency.
Mothers’ Use of Cognitive State Verbs in Picture‐Book Reading and the Development of Children’s Understanding of Mind: A Longitudinal Study
Authors: Adrián Juan E. , Clemente Rosa Ana , Villanueva Lidón
Published: July 2007

Mothers read stories to their children (N = 41) aged between 3.3 years and 5.11 years old, and children then completed two false‐belief tasks. One year later, mothers read a story to 37 of those children who were also given four tasks to assess their advanced understanding of mental states. Mothers’ early use of cognitive verbs in picture‐book reading correlated with their children’s later understanding of mental states. Some pragmatic aspects of maternal input correlated with children’s later outcomes. Two different factors in mothers’ cognitive discourse were identified, suggesting a zone of proximal development in children’s understanding of mental states.
Autonomy and Children’s Reactions to Being Controlled: Evidence That Both Compliance and Defiance May Be Positive Markers in Early Development
Authors: Dix Theodore , Stewart Amanda D. , Gershoff Elizabeth T. , Day William H.
Published: July 2007

This study examined reactions of 1‐year‐olds and young 2‐year‐olds to being controlled by mothers. Mothers’ supportive behavior predicted children’s willing compliance. However, contrary to research with older children, defiance was also associated with variables linked to maternal competence, specifically, mothers’ supportive behavior, autonomy‐granting controls, and low depressive symptoms. At this age high‐defiant children initiated positive interaction with mothers more than did low‐defiant children. With age, children displayed more willing compliance and more active resistance (defiance, low passivity). However, developmental increases in active resistance were absent when mothers were high in depressive symptoms. Findings are consistent with the proposal that in early development active resistance to parents often reflects children’s motivation to control events, not poor parenting or strained parent–child relationships.
Lost in Translation: Methodological Considerations in Cross‐Cultural Research
Authors: Peña Elizabeth D.
Published: July 2007

In cross‐cultural child development research there is often a need to translate instruments and instructions to languages other than English. Typically, the translation process focuses on ensuring linguistic equivalence. However, establishment of linguistic equivalence through translation techniques is often not sufficient to guard against validity threats. In addition to linguistic equivalence, functional equivalence, cultural equivalence, and metric equivalence are factors that need to be considered when research methods are translated to other languages. This article first examines cross‐cultural threats to validity in research. Next, each of the preceding factors is illustrated with examples from the literature. Finally, suggestions for incorporating each factor into research studies of child development are given.
Public–Private Partnerships: Implications for Primary Schooling in Pakistan
Authors: Farah Iffat , Rizvi Sadaf
Published: July 2007

Since the early 1990s, the government of Pakistan has promoted a policy of public–private partnerships to increase access and improve the quality of education in Pakistan. This article describes the evolution of the policy and discusses a variety of partnership arrangements aimed to establish and govern primary schools. It suggests that, while partnerships have positive outcomes and may be a viable option for resourceful communities, they are located in a hierarchical structure and lack equal distribution of power and trust between partners. Partnerships are often temporary and established for the purpose of a transition to privatization. These problems make them an unlikely strategy for a sustained increase in the chances of access to good‐quality schooling for the poor and disadvantaged.
Healthcare in India: Changing the Financing Strategy
Authors: Duggal Ravi
Published: July 2007

The way in which healthcare is financed is critical for equity in access to healthcare. At present the proportion of public resources committed to healthcare in India is one of the lowest in the world, with less than one‐fifth of health expenditure being publicly financed. India has large‐scale poverty and yet the main source of financing healthcare is out‐of‐pocket expenditure. This is a cause of the huge inequities we see in access to healthcare. The article argues for strengthening public investment and expenditure in the health sector and suggests possible options for doing this. It also calls for a reform of the existing healthcare system by restructuring it to create a universal access mechanism which also factors in the private health sector. The article concludes that it is important to over‐emphasize the fact that health is a public or social good and so cannot be left to the vagaries of the market.
“Everyone with Eyes Can See the Problem”: Moral Citizens and the Space of Irish Nationhood
Authors: Tormey Anwen
Published: July 2007

This paper examines Ireland's 2004 Constitutional Amendment which removes birthright citizenship from any future Irish‐born children of immigrant parents. I argue that for particular historical reasons, the ability of the state to convince its citizens of the necessity for this Amendment was remarkable and I suggest that it was able to do so by constructing citizenship as a moral regime and foreign‐nationals and their foetuses as ‘suspect patriots.’ I describe how the notion of immorality is laminated upon black bodies — specifically black pregnant women — and how the presence of black migrant workers, refugees and asylees consequently comes to be experienced in Irish national space as transgressive, their political subjecthood constrained by the supposedly legible abjectivity of their bodies. The issue of race remains unenunciated, and yet, as the Minister for Justice stated during the referendum debate, ‘anyone with eyes can see the problem.’ The Irish government's privileging of moral rather than cultural incommensurability is strikingly similar to culturalist rhetorics of exclusion that are often invoked when race is at issue in European public debate on immigration. Configured upon, and therefore experienced as a type of body, immorality becomes an alibi for race and is naturalized as a form of exclusion and as a potential site of state intervention in the form of xenophobic legislation and policymaking. Reading this decision as merely racist however, fails to give voice to the experiences of Irish Citizens who voted for this Amendment. Their struggle to build a “New Ireland” and to accept a multiculturalist framework in the face of neo‐liberal restructuring policies and a European‐wide retreat from the welfare state must be considered as being in dialectical tension with the ideological smearing of immigrants if we are to fully grasp the complex interaction between relations of power and the privileging of difference.
Evaluation of the Thyroid Transcription Factor‐1 Gene (TITF1) as a Hirschsprung's Disease Locus
Authors: Garcia‐Barceló Maria‐Mercè , Lau Danny Ko‐chun , Ngan Elly Sau‐wai , Leon Thomas Yuk‐yu , Liu Ting‐ting , So Man‐ting , Miao Xiao‐ping , Lui Vincent Chi‐hang , Wong Kenneth Kak‐yuen , Ganster Raymond William , Cass Daniel Thomas , Croaker Geoffrey David Hain , Tam Paul Kwong‐hang
Published: July 2007

Hirschsprung's disease (HSCR, colonic aganglionosis) is an oligogenic entity that usually requires mutations in RET and other interacting loci. Decreased levels of RET expression may lead to the manifestation of HSCR. We previously showed that RET transcription was decreased due to alteration of the TITF1 binding site by two HSCR‐associated RET promoter single nucleotide polymorphisms (SNPs). This prompted us to investigate whether DNA alterations in TITF1 could play a role in HSCR by affecting the RET‐regulatory properties of the TITF1 protein. Our initial study on 86 Chinese HSCR patients revealed a Gly322Ser amino acid substitution in the TITF1protein. In this study we have examined an additional 102 Chinese and 70 Caucasian patients, and 194 Chinese and 60 Caucasian unselected, unrelated, subjects as controls. The relevance of the DNA changes detected in TITF1 by direct sequencing were evaluated using bioinformatics, reporter and binding‐assays, mouse neurosphere culture, immunohistochemistry and immunofluorescence techniques. Met3Leu and Pro48Pro were identified in 2 Caucasian patients and 1 Chinese patient, respectively. In vitro analysis showed that Met3Leu reduced the activity of the RET promoter by 100% in the presence of the wild‐type or HSCR‐associated RET promoter SNP alleles. The apparent binding affinity of the TITF1 mutated protein was not decreased. The Met3Leu mutation may affect the interaction of TITF1 with its protein partners. The absence of Titf1 expression in mouse gut but not in human gut suggests that the role of TITF1 in gut development differs between the two species. TITF1 mutations could contribute to HSCR by affecting RET expression through defective interactions with other transcription factors.
Isolation and characterization of 39 microsatellite loci in the endangered Japanese loach Leptobotia curta
Authors: WATANABE KATSUTOSHI , TAKESHIMA HIROHIKO , IWATA AKIHISA , ABE TSUKASA , UEHARA KAZUHIKO , KAKIOKA RYO , KIHIRA DAIJIRO , NISHIDA MUTSUMI
Published: July 2007

A microsatellite‐enriched genomic library was obtained for the endangered Japanese loach Leptobotia curta, and 39 dinucleotide markers were successfully isolated and characterized. These markers had between one and nine alleles, with expected heterozygosity ranging from 0 to 0.839, in a population from the Lake Biwa–Yodo River system of Japan. Linkage equilibrium was observed in most loci, and only one locus showed significant deviation from Hardy–Weinberg equilibrium. These microsatellite markers will be useful for genetic diversity studies of wild and captive L. curta populations.
fingerprint: visual depiction of variation in multiple sequence alignments
Authors: LOU MELANIE , GOLDING G. BRIAN
Published: July 2007

There is a lack of programs available that focus on providing an overview of an aligned set of sequences such that the comparison of homologous sites becomes comprehensible and intuitive. Being able to identify similarities, differences, and patterns within a multiple sequence alignment is biologically valuable because it permits visualization of the distribution of a particular feature and inferences about the structure, function, and evolution of the sequences in question. We have therefore created a web server, fingerprint, which combines the characteristics of existing programs that represent identity, variability, charge, hydrophobicity, solvent accessibility, and structure along with new visualizations based on composition, heterogeneity, heterozygosity, dN/dS and nucleotide diversity. fingerprint is easy to use and globally accessible through any computer using any major browser. fingerprint is available at http://evol.mcmaster.ca/fingerprint/.
Isolation and characterization of polymorphic microsatellite loci from RAPD product in half‐smooth tongue sole (Cynoglossus semilaevis) and a test of cross‐species amplification
Authors: LIU Y. G. , BAO B. L. , LIU L. X. , WANG L. , LIN H.
Published: July 2007

Eleven polymorphic microsatellite loci have been isolated and characterized from random amplified polymorphic DNA product in half‐smooth tongue sole, Cynoglossus semilaevis. Twenty‐one microsatellites were selected for designing microsatellite primers, of which 11 gave working primer pairs. They had between three and 12 alleles. Observed and expected heterozygosities varied from 0.53 to 0.93, and from 0.52 to 0.80, respectively. Five additional fish species assessed for cross‐species amplification revealed between one and three positive amplifications and between zero and three polymorphic loci per species.