bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacillus subtilis RecG branch migration translocase is required for DNA repair and chromosomal segregation
Authors: Sanchez Humberto , Carrasco Begoña , Cozar M. Castillo , Alonso Juan C. 
Published: July 2007

SummaryThe absence of Bacillus subtilis RecG branch migration translocase causes a defect in cell proliferation, renders cells very sensitive to DNA‐damaging agents and increases ∼150‐fold the amount of non‐partitioned chromosomes. Inactivation of recF, addA, recH, recV or recU increases both the sensitivity to DNA‐damaging agents and the chromosomal segregation defect of recG mutants. Deletion of recS or recN gene partially suppresses cell proliferation, DNA repair and segregation defects of ΔrecG cells, whereas deletion of recA only partially suppresses the segregation defect of ΔrecG cells. Deletion of recG and ripX render cells with very poor viability, extremely sensitive to DNA‐damaging agents, and with a drastic segregation defect. After exposure to mitomycin C recG or ripX cells show a drastic defect in chromosome partitioning (∼40% of the cells), and this defect is even larger (∼60% of the cells) in recG ripX cells. Taken together, these data indicate that: (i) RecG defines a new epistatic group (η), (ii) RecG is required for proper chromosomal segregation even in the presence of other proteins that process and resolve Holliday junctions, and (iii) different avenues could process Holliday junctions.
The essential peptidoglycan glycosyltransferase MurG forms a complex with proteins involved in lateral envelope growth as well as with proteins involved in cell division in Escherichia coli
Authors: Mohammadi Tamimount , Karczmarek Aneta , Crouvoisier Muriel , Bouhss Ahmed , Mengin‐Lecreulx Dominique , Den Blaauwen Tanneke 
Published: July 2007

SummaryIn Escherichia coli many enzymes including MurG are directly involved in the synthesis and assembly of peptidoglycan. MurG is an essential glycosyltransferase catalysing the last intracellular step of peptidoglycan synthesis. To elucidate its role during elongation and division events, localization of MurG using immunofluorescence microscopy was performed. MurG exhibited a random distribution in the cell envelope with a relatively higher intensity at the division site. This mid‐cell localization was dependent on the presence of a mature divisome. Its localization in the lateral cell wall appeared to require the presence of MreCD. This could be indicative of a potential interaction between MurG and other proteins. Investigating this by immunoprecipitation revealed the association of MurG with MreB and MraY in the same protein complex. In view of this, the loss of rod shape of ΔmreBCD strain could be ascribed to the loss of MurG membrane localization. Consequently, this could prevent the localized supply of the lipid II precursor to the peptidoglycan synthesizing machinery involved in cell elongation. It is postulated that the involvement of MurG in the peptidoglycan synthesis concurs with two complexes, one implicated in cell elongation and the other in division. A model representing the first complex is proposed.
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

ABSTRACTNodule 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

ABSTRACTIt 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

ABSTRACTWe 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

ABSTRACTThe 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.
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.
Clostridium difficile‐associated diarrhoea
Authors: Elliott B. , Chang B. J. , Golledge C. L. , Riley T. V. 
Published: July 2007

Abstract 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

SummaryBackground:  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

SummaryThe 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

SummaryBackground:  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

AbstractAims  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.
Public–Private Partnerships: Implications for Primary Schooling in Pakistan
Authors: Farah Iffat , Rizvi Sadaf 
Published: July 2007

Abstract 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

Abstract 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.