bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric lateral inhibitory neural activity in the auditory system: a magnetoencephalographic study
Authors: Okamoto Hidehiko , Kakigi Ryusuke , Gunji Atsuko , Pantev Christo 
Published: May 2007

Abstract

Background
Decrements of auditory evoked responses elicited by repeatedly presented sounds with similar frequencies have been well investigated by means of electroencephalography and magnetoencephalography (MEG). However the possible inhibitory interactions between different neuronal populations remains poorly understood. In the present study, we investigated the effect of proceeding notch-filtered noises (NFNs) with different frequency spectra on a following test tone using MEG.

Results
Three-second exposure to the NFNs resulted in significantly different N1m responses to a 1000 Hz test tone presented 500 ms after the offset of the NFNs. The NFN with a lower spectral edge closest to the test tone mostly decreased the N1m amplitude.

Conclusion
The decrement of the N1m component after exposure to the NFNs could be explained partly in terms of lateral inhibition. The results demonstrated that the amplitude of the N1m was more effectively influenced by inhibitory lateral connections originating from neurons corresponding to lower rather than higher frequencies. We interpret this effect of asymmetric lateral inhibition in the auditory system as an important contribution to reduce the asymmetric neural activity profiles originating from the cochlea.
A review of the methodological features of systematic reviews in maternal medicine
Authors: Sheikh Lumaan , Johnston Shelley , Thangaratinam Shakila , Kilby Mark D , Khan Khalid S 
Published: May 2007

Abstract

Background
In maternal medicine, research evidence is scattered making it difficult to access information for clinical decision making. Systematic reviews of good methodological quality are essential to provide valid inferences and to produce usable evidence summaries to guide management. This review assesses the methodological features of existing systematic reviews in maternal medicine, comparing Cochrane and non-Cochrane reviews in maternal medicine.

Methods
Medline, Embase, Database of Reviews of Effectiveness (DARE) and Cochrane Database of Systematic Reviews (CDSR) were searched for relevant reviews published between 2001 and 2006. We selected those reviews in which a minimum of two databases were searched and the primary outcome was related to the maternal condition. The selected reviews were assessed for information on framing of question, literature search and methods of review.

Results
Out of 2846 citations, 68 reviews were selected. Among these, 39 (57%) were Cochrane reviews. Most of the reviews (50/68, 74%) evaluated therapeutic interventions. Overall, 54/68 (79%) addressed a focussed question. Although 64/68 (94%) reviews had a detailed search description, only 17/68 (25%) searched without language restriction. 32/68 (47%) attempted to include unpublished data and 11/68 (16%) assessed for the risk of missing studies quantitatively. The reviews had deficiencies in the assessment of validity of studies and exploration for heterogeneity. When compared to Cochrane reviews, other reviews were significantly inferior in specifying questions (OR 20.3, 95% CI 1.1–381.3, p = 0.04), framing focussed questions (OR 30.9, 95% CI 3.7- 256.2, p = 0.001), use of unpublished data (OR 5.6, 95% CI 1.9–16.4, p = 0.002), assessment for heterogeneity (OR 38.1, 95%CI 2.1, 688.2, p = 0.01) and use of meta-analyses (OR 3.7, 95% CI 1.3–10.8, p = 0.02).

Conclusion
This study identifies areas which have a strong influence on maternal morbidity and mortality but lack good quality systematic reviews. Overall quality of the existing systematic reviews was variable. Cochrane reviews were of better quality as compared to other reviews. There is a need for good quality systematic reviews to inform practice in maternal medicine.
Characterizing the expression of the human olfactory receptor gene family using a novel DNA microarray
Authors: Zhang Xiaohong , De la Cruz Omar , Pinto Jayant M , Nicolae Dan , Firestein Stuart , Gilad Yoav 
Published: May 2007

Abstract
Background
Olfactory receptor (OR) genes were discovered more than a decade ago, when Buck and Axel observed that, in rats, certain G-protein coupled receptors are expressed exclusively in the olfactory epithelium. Subsequently, protein sequence similarity was used to identify entire OR gene repertoires of a number of mammalian species, but only in mouse were these predictions followed up by expression studies in olfactory epithelium. To rectify this, we have developed a DNA microarray that contains probes for most predicted human OR loci and used that array to examine OR gene expression profiles in olfactory epithelium tissues from three individuals.

Results
We detected expression of 437 (76%) human OR genes in these olfactory epithelia. Interestingly, we detected widespread expression of OR pseudogenes, an observation that may shed light on the mechanism of OR gene choice in the olfactory sensory neurons. To address the hypothesis that OR genes may carry out additional functions, we also characterized the expression of OR genes in a number of non-olfactory tissues.

Conclusion
While our results corroborate the functional annotation of the majority of predicted human odorant receptors, we find that a large number of putative human OR genes are expressed in non-olfactory tissues, sometimes exclusively so. Our evolutionary analysis of ectopically expressed human OR genes does not lend support to the hypothesis that these genes have alternative functions.
Optimal stabilization and path-following controls for a bicycle
Authors: Sharp R S 
Published: May 2007

The article is about stabilizing and path-tracking control of a bicycle by a rider. It is based on previously published work, in which it has been shown how a driver's or rider's preview of the roadway can be combined with the linear dynamics of an appropriate vehicle to yield a problem of discrete-time optimal-linear-control-theory form. In the previous work, it was shown how an optimal ‘driver’ converts path preview sample values, modelled as deriving from a Gaussian white-noise process, into steering control inputs to cause the vehicle to follow the previewed path. The control compromises between precision and ease, to an extent that is controllable through choice of weights in the optimal control calculations. Research into the dynamics of bicycles has yielded a benchmark model, with equations of motion firmly established by extensive cross-checking. Model predictions have been verified for modest speeds by experimental testing. The established optimal linear preview stabilizing and tracking control theory is now brought together with the benchmark bicycle description to yield optimal controls for the bicycle for variations in speed and performance objectives. The resulting controls are installed in the bicycle, giving a virtual rider-controlled system, and frequency responses of the rider-controlled system are calculated to demonstrate tracking capability. Then path-tracking simulations are used to illustrate the behaviour of the controlled system. Tight and loose controls, representing different balances between tracking accuracy and control effort, are calculated and illustrated through the simulations.
Optimization of High-Resolution Melting Analysis for Low-Cost and Rapid Screening of Allelic Variants of Bacillus anthracis by Multiple-Locus Variable-Number Tandem Repeat Analysis
Authors: Fortini Daniela , Ciammaruconi Andrea , De Santis Riccardo , Fasanella Antonio , Battisti Antonio , D’Amelio Raffaele , Lista Florigio , Cassone Antonio , Carattoli Alessandra 
Published: May 2007

AbstractBackground: Molecular genotyping of Bacillus anthracis, the etiologic agent of anthrax, is important for differentiating and identifying strains from different geographic areas and for tracing strains deliberately released in a bioterrorism attack. We previously described a multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) based on 25 marker loci. Although the method has great differentiating power and reproducibility, faster genotyping at low cost may be requested to accurately identify B. anthracis strains in the field.Methods: We used the High Resolution Melter-1 (Idaho Technology) and a saturating dye of double-stranded DNA (LCGreen I) to identify alleles via PCR and melting-curve analysis of the amplicons. We applied high-resolution melting analysis (HRMA) to a collection of 19 B. anthracis strains.Results: HRMA produced reproducible results for 6 of the 25 B. anthracis loci tested. These easily interpretable and distinguishable melting curve results were consistent with MLVA results obtained for the same alleles. The feasibility of this method was demonstrated in testing of different allelic variants for the 6 selected loci.Conclusions: The described HRMA application for screening B. anthracis VNTR loci is fast and widely accessible and may prove particularly useful under field conditions.
Increased Serum Lipoprotein(a) Concentrations and Low Molecular Weight Phenotypes of Apolipoprotein(a) Are Associated with Symptomatic Peripheral Arterial Disease
Authors: Dieplinger Benjamin , Lingenhel Arno , Baumgartner Nadja , Poelz Werner , Dieplinger Hans , Haltmayer Meinhard , Kronenberg Florian , Mueller Thomas 
Published: May 2007

AbstractBackground: Increased concentrations of lipoprotein(a) [Lp(a)] have been considered a genetically determined risk factor for coronary artery and cerebrovascular disease. Only 2 small and conflicting studies have investigated the possibility of an association of peripheral arterial disease (PAD) with high serum Lp(a) concentrations and low molecular weight (LMW) phenotypes of apolipoprotein(a) [apo(a)].Methods: We measured serum concentrations of Lp(a) and apo(a) phenotypes in 213 patients with symptomatic PAD and 213 controls matched for sex, age (within 2 years), and presence of diabetes.Results: Patients with PAD showed significantly higher median serum concentrations of Lp(a) (76 vs 47 mg/L; P = 0.003) and a higher frequency of LMW apo(a) phenotypes (41% vs 26%; P = 0.002) than controls. After adjustment for several potential confounders, increased Lp(a) concentrations (&gt;195 mg/L, i.e., 75th percentile of the entire study sample) and LMW apo(a) phenotypes were significant predictors of PAD, with odds ratios of 3.73 (95% CI 2.08–6.67; P &lt;0.001) and 2.21 (95% CI 1.33–3.67; P = 0.002), respectively.Conclusions: In this study sample, both increased serum concentrations of Lp(a) and the presence of LMW apo(a) phenotypes were associated with the presence of symptomatic PAD independent of traditional and nontraditional cardiovascular risk factors. Because PAD is considered an indicator of systemic atherosclerotic disease, our results suggest a possible role of Lp(a) as a genetically determined marker for systemic atherosclerosis.
Concise Review: Dendritic Cell Development in the Context of the Spleen Microenvironment
Authors: Tan Jonathan K. H. , O'Neill Helen C. 
Published: May 2007

Abstract
The dendritic cell (DC) population in spleen comprises a mixture of cells including endogenous DC progenitors, DC precursors migrating in from blood and bone marrow, and DC in different states of differentiation and activation. A role for different microenvironments in supporting the dynamic development of murine DC of different types or lineages is considered here. Recent evidence for production of DC dependent on splenic stromal cells is reviewed in the light of evidence that cell production is dependent on cells comprising an endothelial niche in spleen. The possibility that self-renewing progenitors in spleen give rise to DC with tolerogenic or regulatory rather than immunostimulatory function is considered.
Disclosure of potential conflicts of interest is found at the end of this article.
What Is the Best Predictor of Future Type 2 Diabetes?
Authors: Abdul-Ghani Muhammad A. , Williams Ken , DeFronzo Ralph A. , Stern Michael 
Published: May 2007

OBJECTIVE—We sought to assess insulin secretion/insulin resistance index in predicting the risk for future type 2 diabetes
RESEARCH DESIGN AND METHODS—A total of 1,551 nondiabetic subjects from the San Antonio Heart Study received an oral glucose tolerance test (OGTT) with measurement of plasma glucose and insulin concentrations at 0, 30, 60, and 120 min at baseline and after 7–8 years of follow-up. Insulin secretion/insulin resistance index was calculated as the product of Matsuda index and ΔI0–30/ΔG0–30 or ΔI0–120/ΔG0–120. The discriminatory power of various prediction models for development of type 2 diabetes was tested with the area under the receiver-operating characteristic (ROC) curve.
RESULTS—Insulin secretion/insulin resistance index (0- to 30- and 0- to 120-min time periods) had the greatest areas under the ROC curve (0.85 and 0.86, respectively), which were significantly greater than the 2-h plasma glucose concentration during the OGTT or the San Antonio Diabetes Prediction Model (SADPM) (P &lt; 0.001 and P &lt; 0.0001, respectively). A model based on the combination of the SADPM and a modified version of the insulin secretion/insulin resistance index or 1-h plasma glucose concentration had equal power to predict the risk for future type 2 diabetes compared with the insulin secretion/insulin resistance index.
CONCLUSIONS—The insulin secretion/insulin resistance index is useful as a predictor of future development of type 2 diabetes. A model based on the combination of the SADPM and either a modified version of the insulin secretion/insulin resistance index or 1-h plasma glucose concentration can equally predict future type 2 diabetes.
Vitamin D, Parathyroid Hormone Levels, and the Prevalence of Metabolic Syndrome in Community-Dwelling Older Adults
Authors: Reis Jared P. , von Mühlen Denise , Kritz-Silverstein Donna , Wingard Deborah L. , Barrett-Connor Elizabeth 
Published: May 2007

OBJECTIVE—Accumulating research suggests low-circulating vitamin D concentrations, i.e., 25-hydroxyvitamin-D [25(OH)D], may be associated with an increased prevalence of metabolic syndrome; however, previous studies have not accounted for parathyroid hormone (PTH) levels. We examined the association of 25(OH)D and PTH with the prevalence of metabolic syndrome in a community-based cohort of older adults.
RESEARCH DESIGN AND METHODS—Participants included 410 men and 660 women, 44–96 years old, who completed a follow-up clinic visit in 1997–1999 as part of the Rancho Bernardo Study. Sex-specific logistic regression models were fit to estimate the odds of ATP III (Adult Treatment Panel III)-defined metabolic syndrome across quintiles of 25(OH)D and PTH, adjusting for age, season, and major lifestyle factors.
RESULTS—In men, there was a significant trend (P = 0.03) of increasing adjusted odds for metabolic syndrome with increasing PTH concentrations, primarily due to an odds ratio of 2.02 (95% CI 0.96–4.24) in men in the top quintile (≥63 ng/l) of PTH concentration. This association remained unchanged after taking into account 25(OH)D levels and excluding men with diabetes or impaired renal function; it was attenuated after adjustment for the homeostasis model assessment of insulin resistance. Neither PTH in women nor 25(OH)D levels in either sex was related to the metabolic syndrome.
CONCLUSIONS—These findings suggest an increased risk of metabolic syndrome with elevated PTH levels in older men and no effect of 25(OH)D concentrations in either sex. The reason for the sex difference in the PTH–metabolic syndrome association is unknown. Prospective studies are necessary to better determine the roles of 25(OH)D and PTH in the etiology of metabolic syndrome.
Objectively Measured Light-Intensity Physical Activity Is Independently Associated With 2-h Plasma Glucose
Authors: Healy Genevieve N. , Dunstan David W. , Salmon Jo , Cerin Ester , Shaw Jonathan E. , Zimmet Paul Z. , Owen Neville 
Published: May 2007

OBJECTIVE—We examined the associations of objectively measured sedentary time, light-intensity physical activity, and moderate- to vigorous-intensity activity with fasting and 2-h postchallenge plasma glucose in Australian adults.
RESEARCH DESIGN AND METHODS—A total of 67 men and 106 women (mean age ± SD 53.3 ± 11.9 years) without diagnosed diabetes were recruited from the 2004–2005 Australian Diabetes, Obesity, and Lifestyle (AusDiab) study. Physical activity was measured by Actigraph accelerometers worn during waking hours for 7 consecutive days and summarized as sedentary time (accelerometer counts/min &lt;100; average hours/day), light-intensity (counts/min 100-1951), and moderate- to vigorous-intensity (counts/min ≥1,952). An oral glucose tolerance test was used to ascertain 2-h plasma glucose and fasting plasma glucose.
RESULTS—After adjustment for confounders (including waist circumference), sedentary time was positively associated with 2-h plasma glucose (b = 0.29, 95% CI 0.11–0.48, P = 0.002); light-intensity activity time (b = −0.25, −0.45 to −0.06, P = 0.012) and moderate- to vigorous-intensity activity time (b = −1.07, −1.77 to −0.37, P = 0.003) were negatively associated. Light-intensity activity remained significantly associated with 2-h plasma glucose following further adjustment for moderate- to vigorous-intensity activity (b = −0.22, −0.42 to −0.03, P = 0.023). Associations of all activity measures with fasting plasma glucose were nonsignificant (P &gt; 0.05).
CONCLUSIONS—These data provide the first objective evidence that light-intensity physical activity is beneficially associated with blood glucose and that sedentary time is unfavorably associated with blood glucose. These objective data support previous findings from studies using self-report measures, and suggest that substituting light-intensity activity for television viewing or other sedentary time may be a practical and achievable preventive strategy to reduce the risk of type 2 diabetes and cardiovascular disease.
Mechanical strain-induced human vascular matrix synthesis: The role of angiotensin II
Authors: Stanley Adrian G , Patel Hash , Knight Abigail L , Williams Bryan 
Published: May 2007

Introduction: Reduced vascular compliance in patients with hypertension results from an increase in extra-cellular matrix (ECM) protein deposition in blood vessels. At least two key factors, namely mechanical strain and neurohumoral mediators, for example Angiotensin II (Ang II), promote fibrogenesis within vessel walls; however potential interactions between these have not been clearly defined. This work examined the direct effect of mechanical strain on matrix mRNA expression and protein synthesis by human vascular smooth muscle (VSM) cells and identified the importance of renin-angiotensin system (RAS) activation in stretch-induced matrix production. Methods: Human VSM cells were exposed either to a cyclical mechanical strain regimen or to Ang II in the presence or absence of the Ang II receptor (AT1 R) antagonist losartan or its more potent metabolite EXP3174. Analysis of matrix mRNA expression (Northerns) and protein synthesis (ELISA) and cellular AT1-receptor protein expression (Westerns) were determined. Results: Ang II increased both collagen α1 (92%, SEM +/-20%) mRNA expression and fibronectin (21% +/- 6%) protein synthesis in static VSM cells compared with unstimulated controls.The effect of Ang II was attenuated by antagonism of the AT 1-receptor (AT1 R). Similarly, mechanical strain induced an increase in both collagen α1 (102% +/- 30%) mRNA expression and fibronectin (50% +/-21%) protein synthesis. Surprisingly, in the absence of exogenous Ang II, AT1-receptor blockade attenuated this stretch-induced increase in matrix synthesis. Mechanical strain also induced an increase in total cellular AT1-receptor protein (30.7% +/- 3.5%) compared with static cells. Conclusion: Both mechanical strain and Ang II increased matrix gene expression and protein synthesis by human VSM cells. The effect of strain was attenuated by AT 1-receptor antagonism. Our results further suggest that mechanical strain may sensitise human VSM cells to the fibrogenic actions of Ang II, perhaps via upregulation of the AT1-receptor.
Losartan reduces sympathetic nerve outflow from the brain of rats with chronic renal failure
Authors: Campese Vito M , Shaohua Ye  , Truong Rex H , Gamburd Michael 
Published: May 2007

Sympathetic nervous system (SNS) activity, measured by norepinephrine (NE) turnover rate, was greater in the posterior hypothalamic (PH) nuclei, the paraventricular nuclei (PVN), and the locus coeruleus (LC) of 5/6 nephrectomised (CRF) rats than of control rats. NE secretion from the PH was also greater in CRF than in control rats. These findings demonstrate that SNS activity plays an important role in the genesis of hypertension associated with CRF. The increase in central SNS activity was mitigated by increased local expression of nitric oxide synthase (NOS)-mRNA and nitric oxide (NOx) production. Because angiotensin II may stimulate the central SNS, we tested the hypothesis that losartan, a specific angiotensin II AT1-receptor antagonist, may lower blood pressure (BP), at least in part, by central noradrenergic inhibition. To this end, we studied two groups of CRF rats. One group received losartan (10 mg/kg body weight) in drinking water between the 3rd and 4th week after nephrectomy, the second group received drinking water without losartan. SNS activity was measured by NE secretion from the PH using the microdialysis technique. NOS-mRNA gene expression was also measured by RT-PCR in the PH, PVN, and LC of CRF and control rats. Losartan reduced systolic BP from 184±3.7 to 152±3.1 mmHg and NE secretion from the PH from 340±9.7 to 247±4.8 pg/ml. CRF rats treated with losartan manifested a significant (p<0.01) increase in the expression of nNOS-mRNA in the PH (from 84±1.2 to 99±2.6), the PVN (from 44±1.5 to 63±2.1), and the LC (from 59±6.7 to 76±2.1). CRF rats also manifested a significant increase (p<0.01) in the expression of IL-1β in the PH (from 41.6±2.8 to 54.3±1.4), PVN (from 44±1.9 to 54±1.5), and LC (from 35.5±1.6 to 53.5±1.9). In conclusion, these studies suggest that the antihypertensive action of losartan in CRF rats may be mediated, at least in part, by inhibition of central SNS outflow. The studies also suggest that the inhibitory action of losartan on the SNS may be mediated by activation of IL-1β, which, in turn, stimulates nNOS, an important modulator of central SNS activity.
Hypertension and its management: A problem in need of new treatment strategies
Authors: Neutel Joel M 
Published: May 2007

Summary Although treatments of hypertension have significantly decreased morbidity and mortality from cerebrovascular disease, the associated reductions in coronary artery disease have been very disappointing. Hypertension is a complex inherited syndrome of cardiovascular risk factors, all of which contribute to the development of heart disease. Angiotensin II receptor blockers (ARBs), such as the highly selective ARB valsartan, provide an alternative treatment strategy to address the multiple issues in coronary artery disease. These agents are well-tolerated and have a once-daily regimen that improves compliance. They bring multiple cardiovascular benefits beyond blood pressure (BP) control, such as renoprotection and cardiovascular growth reduction.