bluuebunny/crossref_metadata_2025_split huggingface dataset:
Esophageal pH Monitoring With the BRAVO Capsule
Authors: Cabrera José , Davis Miriam , Horn Debbie , Pfefferkorn Marian , Croffie Joseph M. 
Published: April 2011

ABSTRACTAim:The aim of the present study was to report the global experience with placement, complication rate, and recording of esophageal pH using the BRAVO capsule at our institution.Patients and Methods:We recorded the rate of any technical problems and complications during placement in all of the patients (ages 4–22 years) who received this device during a 2‐year period. All of the patients undergoing esophagogastroduodenoscopy with the placement of BRAVO pH capsule were included in this analysis. We also examined the pH data recorded on days 1 and 2 for significant day‐to‐day variability during 2 days of pH monitoring.Results:Two hundred eighty‐nine BRAVO pH probes were placed from January 1, 2006 to December 31, 2008. At least 1 day of data was obtained in 278 patients (96.2%). Two days of data were obtained in 274 patients (94.8%). Of all of the reported complications, 1% occurred before deployment of the capsule, 4% occurred during deployment of the capsule, and 9% occurred after successful deployment of the capsule. One patient experienced a superficial esophageal tear that was associated with failure of the capsule to release from the delivery system. No patient requested removal of the capsule and all of the capsules detached within 14 days. In 9.12% of our patients, reflux index was normal on day 1 and abnormal on day 2. There was no statistically significant difference between reflux index recorded on day 1 versus day 2 (P = 0.686).Conclusions:The BRAVO pH capsule is easy to place, safe, and well tolerated by children. Performing a 48‐hour study detected abnormal reflux in an additional 9% of our patients.
Decline of Leaf Hydraulic Conductance with Dehydration: Relationship to Leaf Size and Venation Architecture
Authors: Scoffoni Christine , Rawls Michael , McKown Athena , Cochard Hervé , Sack Lawren 
Published: April 2011

AbstractAcross plant species, leaves vary enormously in their size and their venation architecture, of which one major function is to replace water lost to transpiration. The leaf hydraulic conductance (K leaf) represents the capacity of the transport system to deliver water, allowing stomata to remain open for photosynthesis. Previous studies showed that K leaf relates to vein density (vein length per area). Additionally, venation architecture determines the sensitivity of K leaf to damage; severing the midrib caused K leaf and gas exchange to decline, with lesser impacts in leaves with higher major vein density that provided more numerous water flow pathways around the damaged vein. Because xylem embolism during dehydration also reduces K leaf, we hypothesized that higher major vein density would also reduce hydraulic vulnerability. Smaller leaves, which generally have higher major vein density, would thus have lower hydraulic vulnerability. Tests using simulations with a spatially explicit model confirmed that smaller leaves with higher major vein density were more tolerant of major vein embolism. Additionally, for 10 species ranging strongly in drought tolerance, hydraulic vulnerability, determined as the leaf water potential at 50% and 80% loss of K leaf, was lower with greater major vein density and smaller leaf size (|r| = 0.85–0.90; P &lt; 0.01). These relationships were independent of other aspects of physiological and morphological drought tolerance. These findings point to a new functional role of venation architecture and small leaf size in drought tolerance, potentially contributing to well-known biogeographic trends in leaf size.
Functional Analysis of Corn Husk Photosynthesis
Authors: Pengelly Jasper J.L. , Kwasny Scott , Bala Soumi , Evans John R. , Voznesenskaya Elena V. , Koteyeva Nuria K. , Edwards Gerald E. , Furbank Robert T. , von Caemmerer Susanne 
Published: April 2011

Abstract
The husk surrounding the ear of corn/maize (Zea mays) has widely spaced veins with a number of interveinal mesophyll (M) cells and has been described as operating a partial C3 photosynthetic pathway, in contrast to its leaves, which use the C4 photosynthetic pathway. Here, we characterized photosynthesis in maize husk and leaf by measuring combined gas exchange and carbon isotope discrimination, the oxygen dependence of the CO2 compensation point, and photosynthetic enzyme activity and localization together with anatomy. The CO2 assimilation rate in the husk was less than that in the leaves and did not saturate at high CO2, indicating CO2 diffusion limitations. However, maximal photosynthetic rates were similar between the leaf and husk when expressed on a chlorophyll basis. The CO2 compensation points of the husk were high compared with the leaf but did not vary with oxygen concentration. This and the low carbon isotope discrimination measured concurrently with gas exchange in the husk and leaf suggested C4-like photosynthesis in the husk. However, both Rubisco activity and the ratio of phosphoenolpyruvate carboxylase to Rubisco activity were reduced in the husk. Immunolocalization studies showed that phosphoenolpyruvate carboxylase is specifically localized in the layer of M cells surrounding the bundle sheath cells, while Rubisco and glycine decarboxylase were enriched in bundle sheath cells but also present in M cells. We conclude that maize husk operates C4 photosynthesis dispersed around the widely spaced veins (analogous to leaves) in a diffusion-limited manner due to low M surface area exposed to intercellular air space, with the functional role of Rubisco and glycine decarboxylase in distant M yet to be explained.
Quantitative computed tomography assessment of transfusional iron overload
Authors: Wood John C. , Mo Ashley , Gera Aakansha , Koh Montre , Coates Thomas , Gilsanz Vicente 
Published: April 2011

SummaryQuantitative computed tomography (QCT) has been proposed for iron quantification for more than 30 years, however there has been little clinical validation. We compared liver attenuation by QCT with magnetic resonance imaging (MRI)‐derived estimates of liver iron concentration (LIC) in 37 patients with transfusional siderosis. MRI and QCT measurements were performed as clinically indicated monitoring of LIC and vertebral bone‐density respectively, over a 6‐year period. Mean time difference between QCT and MRI studies was 14 d, with 25 studies performed on the same day. For liver attenuation outside the normal range, attenuation values rose linearly with LIC (r2 = 0·94). However, intersubject variability in intrinsic liver attenuation prevented quantitation of LIC <8 mg/g dry weight of liver, and was the dominant source of measurement uncertainty. Calculated QCT and MRI accuracies were equivalent for LIC values approaching 22 mg/g dry weight, with QCT having superior performance at higher LIC’s. Although not suitable for monitoring patients with good iron control, QCT may nonetheless represent a viable technique for liver iron quantitation in patients with moderate to severe iron in regions where MRI resources are limited because of its low cost, availability, and high throughput.
Diffusion‐weighted imaging for non‐invasive and quantitative monitoring of bone marrow infiltration in patients with monoclonal plasma cell disease: a comparative study with histology
Authors: Hillengass Jens , Bäuerle Tobias , Bartl Reiner , Andrulis Mindaugas , McClanahan Fabienne , Laun Frederik B. , Zechmann Christian Martin , Shah Rajiv , Wagner‐Gund Barbara , Simon Dirk , Heiss Christiane , Neben Kai , Ho Anthony D. , Schlemmer Heinz‐Peter , Goldschmidt Hartmut , Delorme Stefan , Stieltjes Bram 
Published: April 2011

SummaryBone marrow plasma cell infiltration is a crucial parameter of disease activity in monoclonal plasma cell disorders. Until now, the only way to quantify such infiltration was bone marrow biopsy or aspiration. Diffusion‐weighted imaging (DWI) is a magnetic resonance imaging‐technique that may mirror tissue cellularity by measuring random movements of water molecules. To investigate if DWI is capable of assessing bone marrow cellularity in monoclonal plasma cell disease, we investigated 56 patients with multiple myeloma or monoclonal gammopathy of undetermined significance, and 30 healthy controls using DWI of the pelvis and/or the lumbar spine. In 25 of 30 patients who underwent biopsy, bone marrow trephine and DWI could be compared. Of the patients with symptomatic disease 15 could be evaluated after systemic treatment. There was a positive correlation between the DWI‐parameter apparent diffusion coefficient (ADC) and bone marrow cellularity as well as micro‐vessel density (P < 0·001 respectively). ADC was significantly different between patients and controls (P < 0·01) and before and after systemic therapy (P < 0·001). In conclusion, DWI enabled bone marrow infiltration to be monitored in a non‐invasive, quantitative way, suggesting that after further investigations on larger patient groups this might become an useful tool in the clinical work‐up to assess tumour burden.
Improving the immediate management of neutropenic sepsis in the UK: lessons from a national audit
Authors: Clarke Rachel T. , Warnick Janine , Stretton Kate , Littlewood Tim J. 
Published: April 2011

SummaryRecent disquiet at inadequacies in the immediate management of neutropenic sepsis in the UK led to a new, gold standard ‘door‐to‐needle’ time of 1 h for the administration of intravenous antibiotics. The aim of this audit was to identify whether that target is being met nationally, the potential barriers to its achievement, and concrete recommendations for how to overcome these. We also sought to establish the degree of regional heterogeneity in current local management protocols. Questionnaires were sent to haematologists across the UK to determine their unit’s immediate management of patients presenting from the community with possible neutropenic sepsis. Local protocols and audits were also requested. Data covering 95 different hospitals were received, covering a combined catchment area of nearly 30 million people. There were marked regional inconsistencies in the definition of ‘neutropenic sepsis’ and almost every aspect of its immediate management. Only 26% of audited patients (n = 627) received intravenous antibiotics within the target time of 1 h. Median door‐to‐needle times ranged from 30 min to 4 h. Long delays of over 5 h were not uncommon.
AtKC1 is a general modulator of Arabidopsis inward Shaker channel activity
Authors: Jeanguenin Linda , Alcon Carine , Duby Geoffrey , Boeglin Martin , Chérel Isabelle , Gaillard Isabelle , Zimmermann Sabine , Sentenac Hervé , Véry Anne‐Aliénor 
Published: April 2011

SummaryA functional Shaker potassium channel requires assembly of four α‐subunits encoded by a single gene or various genes from the Shaker family. In Arabidopsis thaliana, AtKC1, a Shaker α‐subunit that is silent when expressed alone, has been shown to regulate the activity of AKT1 by forming heteromeric AtKC1–AKT1 channels. Here, we investigated whether AtKC1 is a general regulator of channel activity. Co‐expression in Xenopus oocytes of a dominant negative (pore‐mutated) AtKC1 subunit with the inward Shaker channel subunits KAT1, KAT2 or AKT2, or the outward subunits SKOR or GORK, revealed that the three inward subunits functionally interact with AtKC1 while the outward ones cannot. Localization experiments in plant protoplasts showed that KAT2 was able to re‐locate AtKC1 fused to GFP from endomembranes to the plasma membrane, indicating that heteromeric AtKC1–KAT2 channels are efficiently targeted to the plasma membrane. Functional properties of heteromeric channels involving AtKC1 and KAT1, KAT2 or AKT2 were analysed by voltage clamp after co‐expression of the respective subunits in Xenopus oocytes. AtKC1 behaved as a regulatory subunit within the heterotetrameric channel, reducing the macroscopic conductance and negatively shifting the channel activation potential. Expression studies showed that AtKC1 and its identified Shaker partners have overlapping expression patterns, supporting the hypothesis of a general regulation of inward channel activity by AtKC1 in planta. Lastly, AtKC1 disruption appeared to reduce plant biomass production, showing that AtKC1‐mediated channel activity regulation is required for normal plant growth.
Presence of amplifiable mRNA in acellular hair shafts: utilization to analyze gene expression profiles of black and white hairs
Authors: Tochio Takumi , Tanaka Hiroshi , Nakata Satoru , Yoshizato Katsutoshi 
Published: April 2011

AbstractBackground  We postulated that hair shafts preserve amplifiable messenger RNAs (mRNAs) and that these mRNAs could be utilized to characterize phenotypic differences in hairs at the gene expression level.Objectives  This study aimed to prove the presence of amplifiable mRNAs in the hair shaft and then to utilize them to characterize black and white hairs at the gene expression level.Methods  RNAs were extracted from black and white scalp hair shafts and amplified by quantitative real‐time polymerase chain reaction (qRT‐PCR). Microarray analysis was performed using T7 RNA polymerase‐amplified mRNAs derived from the hair shaft to examine the gene expression profiles of black and white hairs.Results  We showed that hair shaft RNAs contained trace amounts of mRNAs and concluded that the acellular hair shaft contained mRNAs usable for microarray analysis. We termed the mRNA “fossil mRNA” (fmRNA) in this study. Totals of 10 and 2% of the detected genes were expressed at levels more than two‐fold higher in black and white hairs compared with white and black hairs, respectively. We selected five genes and examined their expression levels in five donors by qRT‐PCR. Among them, only hypothetical protein (L1H3 region) human was found to be expressed at 2.69 ± 1.81 (relative ratio) in black hairs.Conclusions  We demonstrated that the scalp hair shaft conserves fmRNAs which are probably remnants that have been expressed during hair differentiation. Consequently, fmRNA is expected to be a useful source of information for the study of phenotypic changes in hairs at the molecular level.
Adaptive responses for seed and leaf phenology in natural populations of sessile oak along an altitudinal gradient
Authors: ALBERTO F. , BOUFFIER L. , LOUVET J.‐M. , LAMY J.‐B. , DELZON S. , KREMER A. 
Published: April 2011

AbstractWe assessed the adaptive potential of seed and leaf phenology in 10 natural populations of sessile oak (Quercus petraea) sampled along two altitudinal transects using common garden experiments. Population differentiation for both phenological traits was observed with high‐altitude populations germinating and flushing later than low altitude ones. However, high genetic variation and heritability values were also maintained within populations, despite slightly decreasing for dates of leaf unfolding with increasing altitude. We suggest that biotic and abiotic fluctuating selection pressures within populations and high gene flow are the main mechanisms maintaining high genetic variation for these fitness related traits. Moreover, changes in selection intensity and/or selection pressures along the altitudinal gradient can explain the reduction in genetic variation observed for leaf phenology. We anticipate that the maintenance of high genetic variation will be a valuable resource for future adaptation of sessile oak populations undergoing an upslope shift caused by climate change.
Vitamin K prophylaxis and late vitamin K deficiency bleeding in infants: Fifth nationwide survey in Japan
Authors: Takahashi Daijiro , Shirahata Akira , Itoh Susumu , Takahashi Yukihiro , Nishiguchi Tomizo , Matsuda Yoshio 
Published: April 2011

AbstractBackground:  In 1980, the first nationwide survey on late vitamin K deficiency bleeding (VKDB) in infants was conducted in Japan, and it was followed by the second, third and fourth nationwide surveys in 1985, 1988 and 1991, respectively. The fifth nationwide survey was designed to ascertain the epidemiology of late VKDB between January 1999 and December 2004.Patients and methods:  Questionnaires were sent to 2161 hospitals in Japan that employed members of the Japan Pediatric Society in March 2005. Responses were received from 1373 hospitals, for a response rate of 63.5%.Results:  The total number of reported cases was 71, including 21 idiopathic type and 16 secondary type. The incidence of late VKDB was estimated to be 1.9 cases per 100 000 births (95% confidence interval: 1.2–3.0) during this survey period. In 34 cases, the presence or absence of any underlying disease was not clarified. A total of 67/71 infants were entirely breast‐fed. Intracranial hemorrhaging was observed in 26 (63.4%) out of 41 infants whose bleeding sites were described in the questionnaires. In 63 cases (88.7%) of late VKDB found in the present survey, however, vitamin K had been given at least once either during or after the neonatal period.Conclusions:  A reevaluation of the current prophylaxis strategy for late VKDB in infants is necessary.
Economic impact of moderate weight loss in patients with Type 2 diabetes: The Fremantle Diabetes Study
Authors: Davis W. A. , Bruce D. G. , Davis T. M. E. 
Published: April 2011

Diabet. Med. 28, 1131–1135 (2011)AbstractAim  To assess the change in the cost of diabetes medication attributable to moderate weight loss in patients with Type 2 diabetes.Methods  Longitudinal data collected annually from 590 patients participating in the observational, community‐based Fremantle Diabetes Study were examined to determine whether moderate weight loss (≥ 5% of initial body weight) was independently associated with diabetes medication cost during 4 years’ follow‐up.Results  Overall, the weight of the cohort decreased significantly during 4.3 ± 0.4 years’ follow‐up by 1.3 ± 6.2 kg (−1.4 ± 7.9% baseline body weight; trend P < 0.001). Moderate weight loss was achieved by 31%. HbA1c improved significantly in the group with moderate weight loss compared with the group without moderate weight loss [−4 ± 16 mmol/mol (−0.3 ± 1.5%) vs. 0 ± 17 mmol/mol (0.0 ± 1.5%), P = 0.015]. Mean (bias‐corrected 95% confidence intervals) diabetes medication costs were $A820 ($A744−907) during follow‐up. As the cost distribution was highly right‐skewed and contained zeros, it was square root (√) transformed before multiple linear regression analysis. The most parsimonious model of baseline associates of √(diabetes medication cost) included glycaemic control, diabetes treatment, diabetes duration, BMI, systolic blood pressure, serum HDL cholesterol (negative), taking lipid‐lowering medication and age (negative) (adjusted R2 = 73.6%). After adjusting for these variables, √(diabetes medication cost) was negatively associated with moderate weight loss (P = 0.026). After entering average values for the cohort into the model, the cost of diabetes medications between baseline and fourth review for an average patient with no weight loss was $A752 compared with $A652 for a patient who attained moderate weight loss, a saving of $A100 (−13.3%).Discussion  These data highlight the economic and clinical benefits of moderate weight loss in Type 2 diabetes.
Waist circumference and metabolic risk factors have separate and additive effects on the risk of future Type 2 diabetes in patients with vascular diseases. A cohort study
Authors: Wassink A. M. J. , van der Graaf Y. , van Haeften T. W. , Spiering W. , Soedamah‐Muthu S. S. , Visseren F. L. J. ,   on behalf of the SMART Study Group
Published: April 2011

Diabet. Med. 28, 932–940 (2011)AbstractAims  To assess the effect of various measures of adiposity and of metabolic risk factors, both separately and in combination, on the risk of future Type 2 diabetes in patients with manifest vascular diseases.Methods  This was a prospective cohort study in 2924 patients (mean age 59 ± 12 years) with manifest atherosclerosis. Metabolic risk factors were defined according to National Cholesterol Education Program criteria for the metabolic syndrome. Incidence of Type 2 diabetes was assessed by questionnaire and subsequent verification.Results  During a median follow‐up of 4.9 years (range 3.0–7.6 years) there were 178 cases (6.1%) of incident Type 2 diabetes. An increase with 1 sd waist circumference showed a strong association with incident Type 2 diabetes in both men (hazard ratio 2.45, 95% CI 1.97–3.04) and women (hazard ratio 1.77, 95% CI 1.38–2.26). Compared with patients with normal (i.e. below the National Cholesterol Education Program criteria for abdominal adiposity) waist circumference and < 3 metabolic risk factors, both patients with normal waist circumference and ≥ 3 metabolic risk factors and patients with high (i.e. above the National Cholesterol Education Program criteria for abdominal adiposity) waist circumference and < 3 metabolic risk factors had an increased risk of Type 2 diabetes (hazard ratio 2.44, 95% CI 1.37–4.36 and hazard ratio 3.61, 95% CI 2.23–5.85, respectively). Patients with both high waist circumference and ≥ 3 metabolic risk factors had the highest risk of developing Type 2 diabetes (hazard ratio 10.76, 95% CI 6.95–16.64).Conclusions  In patients with manifest atherosclerosis, both presence of ≥ 3 metabolic risk factors and presence of a high waist circumference alone are associated with increased risk for developing Type 2 diabetes. The combined presence of ≥ 3 metabolic risk factors and high waist circumference, which is present in 15% of patients, is associated with a 10‐fold increased risk of future Type 2 diabetes. To identify patients with manifest atherosclerosis at the highest risk of developing Type 2 diabetes, fat distribution in combination with metabolic risk factors should be considered.
The prevalence of acne among a group of Portuguese medical students
Authors: Gonçalves G. , Amado J.M. , Matos M.E. , Massa A. 
Published: April 2011

AbstractBackground  Worldwide, very few studies have been published on the prevalence of acne among university students.Objective  The main objective of this study was to estimate the prevalence of acne among Portuguese medical students. We also assessed associated factors and opinions.Methods  Participants were recruited among 145 fifth year medical students. They were asked to complete a questionnaire, and were observed to grade their acne. Acne grading was done using Pillsbury criteria.Results  Ninety‐eight students were assessed and returned the self‐completed questionnaire, 67 (68%) were female students and 31 (32%) male students. The observed prevalence of acne was 61 students (62.2%); 42 (69%) and 18 (30%) had acne grades I and II, respectively; only one was classified as grade III. The prevalence of acne was not significantly associated with gender (P = 0.72), family history of acne (P = 0.65), greasy hair (P = 0.18), smoking habits (P = 0.25) or self‐perceived presence of acne (P = 0.48). Regularity of menstrual cycles was not associated (P = 0.73) with the presence of acne among the 67 women. The majority thought that acne strongly affects self‐image and, to a much lesser extent, personal relationships, academic performance or recruitment to a job.Conclusion  The prevalence of acne in this study was higher than that observed in previous studies among medical students and other non‐university young adults. Opinions about the causes of acne (with hormones in top of the list) were similar to previous studies. Our study sample perceived more serious consequences for self‐image than university students elsewhere and younger Portuguese school children.