bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insights into type IV pilus biogenesis and dynamics from genetic analysis of a C‐terminally tagged pilin: a role for O‐linked glycosylation
Authors: Vik Åshild , Aspholm Marina , Anonsen Jan Haug , Børud Bente , Roos Norbert , Koomey Michael 
Published: August 2012

SummaryType IV pili are surface organelles essential for pathogenicity of many Gram‐negative bacteria. In Neisseria gonorrhoeae, the major subunit of type IV pili, PilE, is a target of its general O‐linked glycosylation system. This system modifies a diverse set of periplasmic and extracellular gonococcal proteins with a variable set of glycans. Here we show that expression of a particular hexa‐histidine‐tagged PilE was associated with growth arrest. By studying intra‐ and extragenic suppressors, we found that this phenotype was dependent on pilus assembly and retraction. Based on these results, we developed a sensitive tool to identify factors with subtle effects on pilus dynamics. Using this approach, we found that glycan chain length has differential effects on the growth arrest that appears to be mediated at the level of pilin subunit–subunit interactions and bidirectional remodelling of pilin between its membrane‐associated and assembled states. Gonococcal pilin glycosylation thus plays both an intracellular role in pilus dynamics and potential extracellular roles mediated through type IV pili. In addition to demonstrating the effect of glycosylation on pilus dynamics, the study provides a new way of identifying factors with less dramatic effects on processes involved in type IV pilus biogenesis.
The opening of the Magellan Strait and its geodynamic implications
Authors: Ghiglione Matías C. , Navarrete‐Rodríguez Angela Teresa , González‐Guillot Mauricio , Bujalesky Gustavo 
Published: August 2012

Terra Nova, 25, 13–20, 2013AbstractThe existence of a Neogene‐Quaternary rift system responsible for the opening of the eastern Magellan strait has been one of the more peculiar tectonic features of the southernmost Andes since its discovery more than a decade ago. However, until now there has been no explanation pinpointing the specific tectonic factors that led to the development of the rift. This work focuses on the interaction between the fault systems and the tectonic regimes that have affected Tierra del Fuego north of the South America–Scotia left lateral strike‐slip plate boundary. Due to a good match between a Jurassic extensional fault array orientation and the principal stress directions related to the strike‐slip plate boundary, we conclude that Jurassic transfer faults reactivated extensionally generating the Magellan rift system. This process was enhanced by northward continental drift, and has implications for the geodynamic behind the separation of South America from Antarctica.
MYB46 directly regulates the gene expression of secondary wall‐associated cellulose synthases in Arabidopsis
Authors: Kim Won‐Chan , Ko Jae‐Heung , Kim Joo‐Yeol , Kim Jungmook , Bae Hyeun‐Jong , Han Kyung‐Hwan 
Published: August 2012

SummaryCellulose is the most abundant biopolymer on Earth. Three cellulose synthases (CESA4, CESA7 and CESA8) are necessary for cellulose production in the secondary cell walls of Arabidopsis. Little is known about how expression of these CESA genes is regulated. We recently identified a cis‐regulatory element (M46RE) that is recognized by MYB46, which is a master switch for secondary wall formation in Arabidopsis. A genome‐wide survey of promoter sequences for the presence of M46REs led to the hypothesis that MYB46 may function as a direct regulator of all three secondary wall‐associated cellulose synthase genes: CESA4, CESA7 and CESA8. We tested this hypothesis using several lines of experimental evidence. All three CESA genes are highly up‐regulated by both constitutive and inducible over‐expression of MYB46 in planta. Using a steroid receptor‐based inducible activation system, we show that MYB46 directly activates transcription of the three CESA genes. We then used an electrophoretic mobility shift assay and chromatin immunoprecipitation analysis to confirm that MYB46 protein directly binds to the promoters of the three CESA genes both in vitro and in vivo. Furthermore, ectopic up‐regulation of MYB46 resulted in a significant increase of crystalline cellulose content in Arabidopsis. Taken together, we have identified MYB46 as a transcription factor that directly regulates all three secondary wall‐associated CESA genes. Yeast one‐hybrid screening identified additional transcription factors that regulate the CESA genes. However, none of the putative regulators appears to be regulated by MYB46, suggesting the multi‐faceted nature of transcriptional regulation of secondary wall cellulose biosynthesis.
Post‐kala‐azar dermal leishmaniasis in visceral leishmaniasis‐endemic communities in Bihar, India
Authors: Singh Rudra Pratap , Picado Albert , Alam Shahnawaz , Hasker Epco , Singh Shri Prakash , Ostyn Bart , Chappuis François , Sundar Shyam , Boelaert Marleen 
Published: August 2012

AbstractWe assessed the prevalence of post‐kala‐azar dermal leishmaniasis (PKDL), a late cutaneous manifestation of visceral leishmaniasis (VL), in 16 VL‐endemic communities in Bihar, India. The prevalence of confirmed PKDL cases was 4.4 per 10 000 individuals and 7.8 if probable cases were also considered. The clinical history and treatment of the post‐kala‐azar dermal leishmaniasis cases are discussed.
Physiological and morphological changes during early and later stages of fruit growth in Capsicum annuum
Authors: Tiwari Aparna , Vivian‐Smith Adam , Ljung Karin , Offringa Remko , Heuvelink Ep 
Published: August 2012

Fruit‐set involves a series of physiological and morphological changes that are well described for tomato and Arabidopsis, but largely unknown for sweet pepper (Capsicum annuum). The aim of this paper is to investigate whether mechanisms of fruit‐set observed in Arabidopsis and tomato are also applicable to C. annuum. To do this, we accurately timed the physiological and morphological changes in a post‐pollinated and un‐pollinated ovary. A vascular connection between ovule and replum was observed in fertilized ovaries that undergo fruit development, and this connection was absent in unfertilized ovaries that abort. This indicates that vascular connection between ovule and replum is an early indicator for successful fruit development after pollination and fertilization. Evaluation of histological changes in the carpel of a fertilized and unfertilized ovary indicated that increase in cell number and cell diameter both contribute to early fruit growth. Cell division contributes more during early fruit growth while cell expansion contributes more at later stages of fruit growth in C. annuum. The simultaneous occurrence of a peak in auxin concentration and a strong increase in cell diameter in the carpel of seeded fruits suggest that indole‐3‐acetic acid stimulates a major increase in cell diameter at later stages of fruit growth. The series of physiological and morphological events observed during fruit‐set in C. annuum are similar to what has been reported for tomato and Arabidopsis. This indicates that tomato and Arabidopsis are suitable model plants to understand details of fruit‐set mechanisms in C. annuum.
Antibody response to the non‐adjuvanted and adjuvanted influenza A H1N1/09 monovalent vaccines in renal transplant recipients
Authors: Salles M.J.C. , Sens Y.A.S. , Malafronte P. , Souza J.F. , Vilas Boas L.S. , Machado C.M. 
Published: August 2012

AbstractBackgroundThe 2009 pandemic influenza A (H1N1) virus spread rapidly throughout Brazil. Non‐adjuvanted and the adjuvanted influenza A H1N1/09 monovalent vaccine were recommended as a single dose to persons at risk including renal transplant recipients (RTR). We analyzed the safety and the immune response of 2 influenza A H1N1/09 monovalent vaccines in RTR, and identified factors influencing the immune response.MethodsA total of 78 RTR received a single dose of either influenza A H1N1 2009 monovalent AS03‐adjuvanted vaccine or a non‐adjuvanted vaccine, and 58 healthy controls received a single dose of non‐adjuvanted vaccine. Antibody responses to influenza A H1N1 were measured by hemagglutination inhibition assay and were compared between groups on the day of vaccination and 21–30 days thereafter, using geometric mean titer (GMT), and seroprotection (SP) and seroconversion (SC) rates.ResultsAmong RTR, after adjuvanted and non‐adjuvanted H1N1 vaccination, the SP rate increased from 16.7% to 61.7% (P < 0.001) and to 50% (P < 0.001), and SC rates were 61.7% and 50%, respectively. For healthy controls, SP rate increased from 25.8% to 89.7% (P < 0.001), and SC rate was 87.9% after vaccination. Pre‐vaccination GMT for the adjuvanted and non‐adjuvanted RTR vaccine groups and healthy controls was 9.7 (95% confidence interval [CI] 7.3–13.1), 8.9 (95% CI 5.4–14.7), and 12.5 (95% CI8.7–18.2), and significantly increased to 49.8 (95% CI 31.3–79.4, P < 0.001), 43.2 (95% CI 16.3–114.4, P < 0.001), and 323.8 (95% CI 213.9–490.2, P < 0.001), respectively. Deceased‐donor type transplant significantly reduced SP (odds ratio [OR] = 4.62, 95% CI 1.36–15.69, P = 0.014) and SC (OR = 6.29, 95% CI 1.89–20.98, P = 0.003) rates, and younger age positively affected SP (OR = 0.11; 95% CI 0.03–0.04, P = 0.001). Adverse events were mild, and renal function showed no change post vaccination.ConclusionRTR vaccinated with either an adjuvanted or non‐adjuvanted monovalent influenza vaccine presented poor response compared with healthy controls. Post‐vaccination adverse events were mild, and no rejection episode or renal dysfunction was observed.
Clonidine abolishes the adverse effects on apoptosis and behaviour after neonatal ketamine exposure in mice
Authors: PONTÉN E. , VIBERG H. , GORDH T. , ERIKSSON P. , FREDRIKSSON A. 
Published: August 2012

BackgroundAn increasing amount of both experimental and epidemiological data indicates that neonatal anaesthesia causes disruption of normal brain development in rodents and primates, as manifested by acute increased apoptosis and long‐lasting altered behaviour and learning. It is necessary to seek strategies that avoid the possible adverse effects after anaesthesia. Our purpose is to show that increased apoptosis and behavioural alterations after ketamine exposure during this period may be prevented by clonidine, a compound already used by paediatric anaesthetists for sedation.MethodsTo investigate the protective properties of clonidine pre‐treatment, five groups of 10‐day‐old mice were injected with either ketamine 50 mg/kg, clonidine 40 μg/kg, ketamine 50 mg/kg 30 min after 10 μg/kg clonidine, ketamine 50 mg/kg 30 min after 40 μg/kg clonidine or saline (control). Apoptosis was measured 24 h after treatment usingFlouro‐Jade staining. Spontaneous activity in a novel environment was tested at an age of 55 days.ResultsPre‐treatment with 40 μg/kg clonidine, but not 10 μg/kg clonidine, 30 min before ketamine exposure abolished ketamine‐induced apoptosis and the behavioural changes observed in the young adult mice. The mice exposed to clonidine alone showed no differences from the saline‐treated (control) mice.ConclusionThe administration of clonidine eliminated the adverse effects of ketamine in this mouse model, suggesting a possible strategy for protection. Alone, clonidine did not cause any adverse effects in these tests.
New graduate occupational therapists feelings of preparedness for practice in Australia and Aotearoa/New Zealand
Authors: Gray Marion , Clark Michele , Penman Merrolee , Smith Julie , Bell Joanna , Thomas Yvonne , Trevan‐Hawke Judith 
Published: August 2012

AimThe development of competent future allied health professionals through academic programmes, professional support and practical education is continually evolving. The aim of this study was to explore the feelings of newly graduated occupational therapists in Australia and Aotearoa/New Zealand regarding their education and work preparedness.MethodsNewly graduated occupational therapists from Australia (n = 178) and Aotearoa/New Zealand (n = 53) who had completed their occupational therapy studies in 2007 were recruited. Participants completed an online survey which explored their preparedness for work; based on professional competencies.ResultsMost newly graduated occupational therapists felt somewhat prepared for practice. However, only 17.1% of Australian new graduates, and even fewer (8.5%) of Aotearoa/New Zealand new graduates felt very well prepared. Participants felt more prepared for the competencies required for ‘managing inwards’ (including interpersonal skills) and less prepared for those required for ‘managing outwards’ (including evidence‐based practice).ConclusionsThis study provides the first international comparison into the feelings of competence and preparedness for practice of new graduates of occupational therapy from Australia and Aotearoa/New Zealand. Given the importance of competencies, such as evidence‐based practice to the progress of the profession, there is a need to further explore methods to increase feelings of preparedness in these areas.
Cd2+ affects the growth, hierarchical structure and peptide composition of the biosilica of the freshwater diatom Nitzschia palea (Kützing) W. Smith
Authors: Heredia Alejandro , Figueira Etelvina , Rodrigues Carina T. , Rodríguez‐Galván Andrés , Basiuk Vladimir A. , Vrieling Engel G. , Almeida Salomé F. P. 
Published: August 2012

SUMMARYBiosilica from diatoms is formed at ambient conditions under the control of biological and physicochemical processes. The changes in growth and biosilica formation through uptake of different concentrations of Cd2+ by the diatom Nitzschia palea (Kützing) W. Smith was investigated, correlating Cd2+ effects to changes in the biosilica nanostructure and the relative content of the encapsulated biomolecules. Diatom growth rates at different Cd2+ concentrations (as 1, 2, 3, 4, and 5 × 10−1 mg L−1 CdCl2) were studied in order to determine the concentrations at which sublethal effects were visible, allowing the harvest of sufficient diatom cells for further experiments. We found a clear correlation between the Cd2+ concentrations and both the nanostructure of the biosilica and content of encapsulated peptides. Cd2+ induced biosilica deformation was assessed by scanning electron microscopy and attenuated total reflectance‐Fourier Transformed Infrared Spectroscopy (FTIR), revealing that micromorphological changes in frustule features (striae, costae, pores) and nanostructural modifications (structure of the silica and conformation of the encapsulated peptides) occurred at applied Cd2+ concentrations of 2 and 3 × 10−1 mg L−1. In particular the FTIR contribution of peptides decreased at elevated Cd2+ concentrations, whereas shifts in wave number of several relevant organic bonds as C = O stretching (1765 cm−1) and possibly hydrated sulfate (1160, 1110 and 980 cm−1) were assigned. Additional analysis of the amide I band showed a relative increase in β‐sheet structure (1680–1620 cm−1) when Cd2+ concentration increased. Cadmium uptake clearly affected the molecular ordering of the biosilica in Nitzschia palea, most probably by interfering in biological or physicochemical processes involved in diatom biosilicification.
Growth and uptake kinetics of phosphate by benthic microalga Nitzschia sp. isolated from Hiroshima Bay, Japan
Authors: Yamamoto Tamiji , Suzuki Masami , Kim Kyunghoi , Asaoka Satoshi 
Published: August 2012

SUMMARYIn the present study, we experimentally investigated the phosphate uptake kinetics of benthic microalga Nitzschia sp. isolated from Hiroshima Bay, Japan. The maximum uptake rate (ρmax) obtained by short‐term experiments was 6.84 pmol cell−1 h−1 for phosphate. The half‐saturation constant for uptake (KS) was 61.2 µmol cell−1 h−1. Both the ρmax and Ks of this species were extremely high, suggesting that Nitzschia sp. is adapted to benthic environments, where nutrient concentrations are much higher than in the water column. The specific maximum growth rate (µ'max) and minimum cell quota (Q0) for the P‐limited condition, obtained by a semi‐continuous growth experiment, were 0.48 day−1 and 0.045 pmol cell−1, respectively. It is concluded that Nitzschia sp. could be a ‘storage strategist’ species, meaning it adapts so as to minimize the influence of fluctuations in phosphate conditions resulting from the change in redox conditions of sediment due to bioturbation.
GNB3 C825T polymorphism is associated with postural tachycardia syndrome in children
Authors: Nakao Ryota , Tanaka Hidetaka , Takitani Kimitaka , Kajiura Mitsugu , Okamoto Naoyuki , Kanbara Yukiko , Tamai Hiroshi 
Published: August 2012

AbstractAimPostural tachycardia syndrome (POTS) is one of the most frequent forms of chronic orthostatic intolerance in children and adolescents. The aim of the present study was to examine the influence of a genetic background on POTS.MethodsA total of 96 children and adolescents with orthostatic dysregulation were studied. The polymorphism of the G protein β3 subunit (GNB3) C825T and G protein α subunit (GNAS1) T131C of genes encoding components of the autonomic nervous system were determined and compared with circulatory responses to active standing.ResultsIn the GNB3 gene C825T polymorphism, the CT and TT genotype had a significant lower supine heart rate and a larger increase of heart rate by standing than the CC, associated with evaluated power of the high‐frequency component of heart rate variability. According to the criteria of the Japanese clinical guidelines, 48 children were diagnosed as POTS and 30 were as normal responder with somatoform disorder (SD). In GNB3 C825T polymorphism, the TT genotype was more frequently found in the POTS group (45.8%) than in the SD group (25.0%; P = 0.036). In the GNAS1 T393C, the genotype frequencies for the T393C polymorphisms of GNA1 did not differ significantly between the groups.ConclusionThe gene polymorphisms GNB3 C825T might be a risk factor for POTS through the enhanced vagal withdrawal of the heart in children and adolescents.
Treatment of preterm infants with West syndrome: Differences due to etiology
Authors: Mure Takeo , Nakagawa Taku , Okizuka Yo , Takami Yuichi , Oyazato Yoshinobu , Nagase Hiroaki , Maruyama Azusa , Adachi Masao , Takada Satoshi , Matsuo Masafumi 
Published: August 2012

AbstractBackgroundThis study was conducted with a particular focus on preterm infants with West syndrome (WS) to evaluate differences in the first responses to oral medication based on etiology.MethodsMedical records of 53 patients with WS, treated at five institutions between 2005 and 2009, were reviewed retrospectively. Patients were divided into six groups based on the time of brain insult, and evaluated for short‐term outcomes using oral anti‐epileptic agents and synthetic adrenocorticotropic hormone.ResultsThe sample consisted of 15, six, 14, two, four, and 12 patients classified, on the basis of apparent time of acquisition of etiology, into the prenatal, term, preterm, postnatal, other, and no identified etiology groups, respectively. Average age of onset in the term group was 3.3 ± 1.0 months, significantly earlier than in the prenatal, preterm, postnatal and no identified etiology groups (P < 0.05). All patients in the term group had experienced seizures before the onset of WS. Only patients in the preterm group had only experienced neonatal seizures, and responded better to treatment. Patients in the preterm group had better responses to treatment, especially oral medication, compared with those in the prenatal and term groups. The prevalence of relapse of seizures in the preterm group (14%) was significantly lower than that in the prenatal group.ConclusionsPreterm WS patients responded well to treatment. Distinguishing WS patients on the basis of different etiologies is important for evaluating the effectiveness of treatment.
Risk factors for community‐acquired urinary tract infection caused by ESBL‐producing bacteria in children
Authors: Kizilca Ozgur , Siraneci Rengin , Yilmaz Alev , Hatipoglu Nevin , Ozturk Erkut , Kiyak Aysel , Ozkok Dilek 
Published: August 2012

AbstractBackgroundThe aim of the present study was to investigate the risk factors of antimicrobial resistance in children with urinary tract infection caused by extended‐spectrum beta‐lactamase (ESBL)‐producing bacteria.MethodsA total of 344 patients diagnosed with urinary tract infection (UTI) between January 2008 and December 2009 were enrolled in this retrospective study. Causative microorganisms were ESBL‐producing bacteria in 148 patients and non‐ESBL‐producing bacteria in 196 patients. There was no difference between the two groups regarding distribution of age, sex and length of follow up.ResultsThe most frequent causative agent was Escherichia coli, of which 41.4% were ESBL producing. Among Klebsiella species, 53.2% were ESBL producing. The proportion of ESBL‐producing bacteria that were resistant to antibiotics was 83.1% for trimethoprim/sulfamethoxazole, 18.2% for nitrofurantoin, 47.3% for quinolones, and 39.9% for aminoglycosides. For non‐ESBL‐producing bacteria, the resistance rate was 62.2% for trimethoprim/sulfamethoxazole, 4.6% for nitrofurantoin, 9.7% for quinolones, and 9.7% for aminoglycosides. Age <1 year, high UTI recurrence rate, long duration of prophylaxis, use of cephalosporins for prophylaxis, hospitalization within the previous 3 months and clean intermittent catheterization were found to be significant risk factors for ESBL‐producing bacteria (P < 0.05). Logistic regression analysis identified age <1 year and high recurrence UTI rate to be independent risk factors, increasing the risk 1.74‐fold and 2.25‐fold, respectively.ConclusionsRecognition of the risk factors for ESBL‐producing bacteria may be helpful to determine new policies in the management of UTI. Recurrence of UTI should be prevented especially in the first year of life, and prophylactic cephalosporins should be avoided.
Effects of aggressive parenteral nutrition on growth and clinical outcome in preterm infants
Authors: Can Emrah , Bülbül Ali , Uslu Sinan , Cömert Serdar , Bolat Fatih , Nuhoğlu Asiye 
Published: August 2012

AbstractBackgroundThe goal of nutrition in the preterm infant is to achieve postnatal growth approximating normal fetal growth. During the early postnatal period, protein intake must be sufficient to achieve normal postnatal growth in extremely low‐birthweight infants. The aim of this study was to test the hypothesis that giving higher amounts of amino acids and lipids to infants born at <34 gestational weeks (GW) may improve growth at the 40th week of gestation and have a positive preventive effect on development of retinopathy of prematurity (ROP).MethodsFifty‐three neonates born at <34 GW and hospitalized in the neonatal intensive care unit (NICU) were included in this prospective study. They were randomly divided into two groups. Group 1 received aggressive parenteral nutrition (PN) (amino acids 3 g/kg per day and lipids 2 g/kg per day on first day of life). Group 2 received conventional PN (amino acids 1.5 g/kg per day and lipids 1 g/kg per day on first day of life). The anthropometric measurements, clinical outcomes and serum levels of insulin‐like growth factor‐I (IGF‐I), IGF binding protein (IGFBP) and thyroid hormones were compared between groups.ResultsAt 40 weeks of gestation, height, head circumference and serum IGF‐I and IGFBP3 were statistically higher in the group receiving aggressive PN. Thyroid hormones were not affected by aggressive PN. The lower levels of IGF‐I and IGFBP3 in the group receiving conventional PN were negatively correlated with development of ROP.ConclusionAggressive PN seems to positively affect neonates' anthropometric measurements at the 40th gestational week and the development of ROP. These effects may be related to high levels of IGF‐I and IGFBP3.