bluuebunny/crossref_metadata_2025 huggingface dataset:
The Permanence in a Single Species Nonautonomous System with Delays and Feedback Control
Authors: Feng Xiaomei , Zhang Fengqin
Published: February 2010

We consider a single species nonautonomous system with delays and feedback control. A general criterion on the permanence for all positive solutions is established. The results show that the feedback control does not influence the permanence of species.
Effect of Ghrelin on Glucose-Insulin Homeostasis: Therapeutic Implications
Authors: Sangiao-Alvarellos Susana , Cordido Fernando
Published: February 2010

Ghrelin is a 28-amino-acid peptide that displays a strong growth hormone- (GH-) releasing activity through the activation of the growth hormone secretagogue receptor (GHSR). The first studies about role of ghrelin were focused on its orexigenic ability, but despite indisputable pharmacological data, the evidence for a physiological role for ghrelin in the control of appetite is much less clear. Mice with targeted deletion of either ghrelin or the GHSR exhibit an essentially normal metabolic phenotype when fed a regular chow diet, suggesting that ghrelin may have a redundant role in the regulation of food intake. RNAs for ghrelin as well as GHSR are expressed in the pancreas of rats and humans and several studies propose that ghrelin could have an important function in glucose homeostasis and insulin release, independent of GH secretion. Low plasma ghrelin levels are associated with elevated fasting insulin levels and insulin resistance, suggesting both physiological and pathophysiological roles for ghrelin. For this reason, at least theoretically, ghrelin and/or its signalling manipulation could be useful for the treatment or prevention of diseases of glucose homeostasis such as type 2 diabetes.
Statistical Evaluations of the Reproducibility and Reliability of 3‐Tesla High Resolution Magnetization Transfer Brain Images: A Pilot Study on Healthy Subjects
Authors: Zou Kelly H. , Du Hongyan , Sidharthan Shawn , DeTora Lisa M. , Chen Yunmei , Ragin Ann B. , Edelman Robert R. , Wu Ying
Published: February 2010

Magnetization transfer imaging (MT) may have considerable promise for early detection and monitoring of subtle brain changes before they are apparent on conventional magnetic resonance images. At 3 Tesla (T), MT affords higher resolution and increased tissue contrast associated with macromolecules. The reliability and reproducibility of a new high‐resolution MT strategy were assessed in brain images acquired from 9 healthy subjects. Repeated measures were taken for 12 brain regions of interest (ROIs): genu, splenium, and the left and right hemispheres of the hippocampus, caudate, putamen, thalamus, and cerebral white matter. Spearman′s correlation coefficient, coefficient of variation, and intraclass correlation coefficient (ICC) were computed. Multivariate mixed‐effects regression models were used to fit the mean ROI values and to test the significance of the effects due to region, subject, observer, time, and manual repetition. A sensitivity analysis of various model specifications and the corresponding ICCs was conducted. Our statistical methods may be generalized to many similar evaluative studies of the reliability and reproducibility of various imaging modalities.
Long-Term Effects of Metformin and Lifestyle Modification on Nonalcoholic Fatty Liver Disease Obese Adolescents
Authors: Tock Lian , Dâmaso Ana R. , de Piano Aline , Carnier June , Sanches Priscila L. , Lederman Henrique Manoel , Ernandes Regina M. Y. , de Mello Marco Túlio , Tufik Sérgio
Published: February 2010

Objective. To assess the long-term effects of metformin in combination with lifestyle intervention and its association between insulin levels and the degree of steatosis at ultrasonography (US) in obese adolescents.Methods. Thirty-five postpubertal obese boys were randomized into two groups: one receiving metformin in combination with a multidisciplinary lifestyle intervention versus a placebo group, which also received the same intervention. The visceral, subcutaneous fat and degree of steatosis were measured by ultrasonography. Fasting blood samples were collected to analyze glucose, insulin, insulin resistance, and aminotransferases. Repeated ANOVA measures were used to compare changes over time and between groups, and Spearman's correlations were used to identify an association between insulin and the degree of steatosis at US.Results. There was a positive correlation between the degree of steatosis at US with insulin concentrations and HOMA-IR. Long-term therapy plus metformin significantly reduced body weight, body mass index, insulin, HOMA-IR, and visceral fat.Conclusions. Metformin was more effective than the placebo in improving clinical parameters associated with obesity and steatosis.
Validation of a Novel Physical Activity Assessment Device in Morbidly Obese Females
Authors: Kwon Soyang , Jamal Mohammad , Zamba Gideon K. D. , Stumbo Phyllis , Samuel Isaac
Published: February 2010

Assessment of physical activity in morbidly obese subjects is important especially in bariatric surgery. We examined the validity of Intelligent Device for Energy Expenditure and Activity (IDEEA) for measuring physical activity and sedentary behavior in morbidly obese women. Activity types, gait counts, and speed detected by the IDEEA monitor were compared to those reported by an observer. The IDEEA monitor detected activity types and gait counts with relatively high accuracy, although slightly lower in extremely obese women than in normal weight controls. The IDEEA monitor accurately estimated gait speeds in both groups. Since gait speed predicts energy expenditure more accurately than gait counts, it is of greater clinical relevance. Reliability of the IDEEA monitor was excellent. The IDEEA monitor is a valid instrument for measuring physical activity and sedentary behavior in extremely obese women, and therefore has potential applications in bariatric surgery both in preoperative evaluation and long-term follow-up.
Variational Approaches for the Existence of Multiple Periodic Solutions of Differential Delay Equations
Authors: Cheng Rong , Hu Jianhua
Published: February 2010

The existence of multiple periodic solutions of the following differential delay equation x′(t) = −f(x(t − r)) is established by applying variational approaches directly, where x ∈ ℝ, f ∈ C(ℝ, ℝ) and r > 0 is a given constant. This means that we do not need to use Kaplan and Yorke′s reduction technique to reduce the existence problem of the above equation to an existence problem for a related coupled system. Such a reduction method introduced first by Kaplan and Yorke in (1974) is often employed in previous papers to study the existence of periodic solutions for the above equation and its similar ones by variational approaches.
Aided Air Conduction Threshold as a Predictor of Cochlear Reserve in Otosclerosis Patients
Authors: Abdelghaffar H. , Fakhry S. , Fawzy T.
Published: February 2010

Otosclerosis classically presents with conductive deafness. However, mainly in older patients or those with a progressive (active) form of this disease, it presents with elevated bone conduction (BC) thresholds. In many cases, an elevation in the BC threshold during otosclerosis is not a true indicator of ‘cochlear reserve’ and this apparent loss can be corrected by surgery. It is generally accepted that in those patients, elevated BC thresholds are not due to pure sensorineural hearing loss but to the Carhart effect. Speech discrimination tests are routinely done, and the results of these tests determine if a patient is a good candidate for surgery. In most institutions, those with poor speech discrimination scores are considered to be poor candidates due to inadequate cochlear reserve. Using hearing-aid-assisted pure-tone audiometry, we developed an accurate method to identify suitable candidates for surgery among the patients with elevated BC thresholds. This method is meant to complement speech discrimination tests in predicting the success of surgery in those patients. Different variables render speech discrimination tests unreliable in many patients. The rationale behind the current study was the lack of an easy and accurate clinical method to determine if a patient has a good cochlear reserve, and to predict the postoperative hearing threshold outcome.
Impact of Surgical Severity and Analgesic Treatment on Plasma Corticosterone in Rats during Surgery
Authors: Goldkuhl R. , Klockars A. , Carlsson H.-E. , Hau J. , Abelson K.S.P.
Published: February 2010

Tissue injury and anaesthesia during surgery induce a stress response associated with increased glucocorticoid secretion from the adrenal glands. This response alters the normal physiology and may cause postoperative morbidity, as well as affect the results during acute experiments. The aim of the present investigation was to study the effect of surgical severity and analgesic treatment on circulating corticosterone in male Sprague-Dawley rats. Male rats were treated with either lidocaine infiltrated during surgery, buprenorphine (0.05 or 0.1 mg/kg subcutaneously) or saline subcutaneously. Each treatment group was subjected to either arterial catheterisation or arterial catheterisation and laparotomy. A catheter was inserted in the common carotid artery and blood was collected during surgery and during anaesthesia 6 h after surgery. Lidocaine treatment reduced the corticosterone levels compared to saline treatment after catheterisation but not after laparotomy. Buprenorphine treatment reduced the corticosterone levels during the first hour after surgery after both catheterisation and laparotomy. The higher buprenorphine dose led to an earlier and more pronounced reduction, especially after laparotomy. In the present study, the corticosterone response during surgery in laboratory rats is correlated with the severity of the procedure, and buprenorphine reduces the surgical stress response more effectively than lidocaine treatment.
Relationship between Helicobacter pylori Tyrosine-Phosphorylated CagA-Related Markers and the Development of Diffuse-Type Gastric Cancers: A Case-Control Study
Authors: Wada Yoshihiro , Ito Masanori , Takata Shunsuke , Tanaka Shinji , Yoshihara Masaharu , Chayama Kazuaki
Published: February 2010

Background/Aims: Tyrosine phosphorylation of the EPIYA motif in Helicobacter pylori CagA (CagA-P) plays an important role in toxic reaction. Diffuse-type gastric cancer (DGC) has a poor prognosis. We tried to clarify the expression level of CagA-P in DGC patients. Methods: We enrolled 42 early-stage DGC patients (DGC group; 20 males, 22 females, mean age 58.2 years) and 42 age- and gender-matched atrophic gastritis (AG) patients (AG group) as controls. We evaluated histological and serological gastritis and examined two markers; the serum titer of anti-CagA-P antibody and CagA-P expression in gastric mucosa. Results: In the DGC group, we found significantly higher corpus histological gastritis scores for activity, atrophy, and intestinal metaplasia. The titer of anti-CagA-P antibody and CagA-P expression in the corpus were significantly higher in the DGC group, especially in females (p < 0.05). Sixteen patients (38.1%) in the DGC group showed both positive markers, and the odds ratio for DGC occurrence was 4.00 (95% CI = 1.07–14.91), while that for females was 9.00 (95% CI = 1.29–62.97). Conclusions: CagA-P plays a role in active corpus gastritis, which may link to DGC carcinogenesis. Clinical quantification of CagA-P-related markers may be useful for the evaluation of DGC risk, especially in females.
Gene Expression Profiles in Fetal and Neonatal Rat Offspring of Energy-Restricted Dams
Authors: Hietaniemi Mirella , Santaniemi Merja , Malo Elina , Ukkola Olavi , Kesäniemi Y. Antero , Jokela Maarit
Published: February 2010

Background/Aims: Nutrition during fetal and early postnatal development can have permanent effects on physiology resulting in an increased risk for disease in later life. The aim of this study was to explore changes in gene expression related to maternal energy restriction during pregnancy in rat fetuses and in neonatal rat offspring. Methods: From day 4 of gestation until parturition, energy-restricted dams received either 75 or 50% of ad libitum food intake. Microarray analyses were performed on whole 13- and 17-day fetuses and 1-day-old pups. Protein and fat contents of the dams’ milk were analyzed in the different feeding groups. Results: A surprisingly small number of genes were differentially expressed between the groups, probably due to the strict control of fetal development. Interestingly, the expressions of many pancreatic digestion enzymes were reduced in the 1-day-old pups of the energy-restricted dams. A statistically significant difference in milk protein content was observed on day 1 post-partum between the gestationally food-restricted groups. Conclusions: The expressions of several genes that may have an important role in the normal development of organs were affected by undernutrition during fetal development. In addition, undernutrition may have affected the function of the exocrine pancreas.
Preprandial Single Oral Dose of Sitagliptin Does Not Affect Circulating Ghrelin and Gastrin Levels in Normal Subjects
Authors: Huang Chen-Ling , Hsu Chung-Huei , Huang Kuo-Cherh , Su Hsiu-Yueh , Weng Shuen-Fu
Published: February 2010

Aims: To determine the effect of an oral dose of sitagliptin on the secretion of ghrelin and gastrin hormones. Methods: Ten healthy volunteers were recruited in this study. A baseline blood sample was drawn before oral dosing with a 100-mg tablet of sitagliptin. Two blood samples were obtained 0.5 and 1 h after dosing. Three additional postprandial blood samples were drawn at 0.5, 1, and 2 h. Radioimmunoassay was used for determining hormonal levels. A Student’s t test, Pearson correlation analysis, and multivariate approach to repeated-measures analysis of variance were used for statistics. Results: After sitagliptin dosing, but before the meal, there was no significant change in circulating ghrelin, gastrin, insulin, and glucose levels. Only after meal loading was there a progressive and persistent decline in ghrelin levels until the end of the study, while a rapid and temporary rise in gastrin, insulin, and glucose levels at 0.5 h was observed. The levels of gastrin, insulin, and glucose then declined progressively. Conclusions: Preprandial oral dose of sitagliptin does not affect circulating ghrelin, gastrin, insulin, and glucose concentrations in normal subjects. Decreased ghrelin and increased gastrin and insulin levels occurred only after meal loading. These results support the theory that sitagliptin might not cause appetite-enhanced body weight gain and insulin-induced hypoglycemia.
Functional and Histologic Assessment of Rat Gastric Mucosa after Chronic Treatment with Sulphurous Thermal Water
Authors: Coruzzi Gabriella , Adami Maristella , Pozzoli Cristina , Solenghi Elvira , Grandi Daniela
Published: February 2010

The effect of a chronic (4 weeks) administration of sulphurous thermal water on gastric acid secretion and mucosal defense was investigated in rats. Animals were randomized to receive daily intake of tap water or of thermal water obtained from a local spa center (Tabiano, Parma, Italy). Rats were followed for one month as for water and food consumption, body weight and general conditions. At the end of the watering period, the following study protocols were carried out: (a) study of basal and stimulated gastric acid secretion under general anesthesia, and (b) study of the gastric mucosal resistance against the damage induced by ethanol and indomethacin in conscious rats. Basal acid secretion and the acid response to pentagastrin or to histamine were similar in rats assuming ordinary drinking water or thermal water. As for resistance to gastric damage, histological, but not macroscopic, evaluation revealed that rats which assumed thermal water were slightly more resistant to the gastrolesive effect of ethanol (either absolute or diluted). Again, when indomethacin was used as a noxious stimulus, no difference was noted between the two groups as for macroscopic damage; only a nonsignificant reduction of damage was observed histologically in stomachs of rats assuming thermal water. In conclusion, these results indicate that chronic treatment of rats with thermal water, rich in sulphur compounds, may have only minimal effects on the rat gastric mucosa and did not significantly affect mucosal defense mechanisms. The observed tendency to gastroprotection would possibly need further investigation with longer periods of administration.
One-Year Case Fatality and Disability after Posterior Circulation Infarction in a Chinese Hospital-Based Stroke Study
Authors: Tao Wen-Dan , Kong Fan-Yi , Hao Zi-Long , Lin Sen , Wang De-Ren , Wu Bo , Liu Ming
Published: February 2010

Background and Purpose: Controversy exists as to whether posterior circulation infarction (PCI) has a poorer outcome compared to anterior circulation infarction (ACI). We aimed to investigate whether PCI had different clinical outcomes from ACI in Chinese patients with ischemic stroke. Methods: Data on ischemic stroke patients with ACI or PCI were collected including demographics, risk factors and 1-month, 3-month, and 1-year case fatality and disability (defined as modified Rankin Scale 3–5). Multivariate regression models were used to analyze predictors for death and disability. Results: Of the 1,962 enrolled cases, 433 (22.1%) had PCI. The case fatality of PCI at 1-month, 3-month and 1-year follow-up (FU) were lower than that of ACI (3.93, 5.3 and 9.7% vs. 7.26, 9.3 and 13.7%, p <0.05), and the proportion of disability was also lower in PCI at 3-month FU (19.6 vs. 29.1%, p<0.001) and 1-year FU (6.5 vs. 15.2%, p<0.001). The adjusted hazard ratio of death for PCI was 0.52 at 1 month (95% CI 0.29–0.94) and 0.52 at 3 months (95% CI 0.31–0.85), and the adjusted odds of disability in patients with PCI was 0.53 at 1 year (95% CI 0.35–0.81). Conclusions: In our cohort, patients with PCI have a lower risk of death at 1- and 3-month FU and a lower proportion of disability at 1-year FU, which needs to be verified by future studies.
Use of a Tunnelled Pleural Catheter for the Management of Refractory Hepatic Hydrothorax: A New Therapeutic Option
Authors: Mercky Pascale , Sakr Lama , Heyries Laurent , Lagrange Xavier , Sahel José , Dutau Hervé
Published: February 2010

Refractory hepatic hydrothorax poses a challenging therapeutic dilemma, as treatment options are limited. Herein, we describe the case of a 48-year-old lady with advanced cirrhosis and recurrent transudative pleural effusion despite a sodium-restricted diet, optimal diuretic therapy and transjugular intrahepatic portosystemic shunt. Given the patient’s platelet and coagulation disorders, thoracoscopic pleurodesis was deemed unsafe. Instead, a tunneled pleural catheter (PleurX®) was inserted under local anesthesia. Pleural drainage was achieved at the time of catheter placement and subsequently according to the patient’s symptoms. Symptomatic improvement and gradual decrease of drainage volumes were noted. Six months following placement of PleurX, methicillin-resistant Staphylococcus aureus cellulitis at the insertion site prompted catheter removal. No pleural effusion was seen on chest X-ray at that time. Subsequent follow-up revealed spontaneous pleurodesis, as no recurrence of pleural effusion was seen over a 6-month follow-up period. Very few data are available with regard to the use of indwelling pleural catheters for benign transudative pleural effusion, and more specifically hepatic hydrothorax. Herein, we present this novel potential indication of the indwelling pleural catheter and illustrate the successful clinical outcome.
Preventive Effect of Commercial Desensitizing Toothpastes on Bovine Enamel Erosion in vitro
Authors: Kato M.T. , Lancia M. , Sales-Peres S.H.C. , Buzalaf M.A.R.
Published: February 2010

This study evaluated in vitro commercial desensitizing toothpastes with respect to the prevention of erosion and explored the effect of their agents alone or in combination with fluoride. Bovine enamel blocks were randomly allocated to five groups of 20 and exposed to: Sensodyne ProNamel (1,425 ppm F as NaF, 5% KNO3), Sensodyne Original (no fluoride, 10% SrCl2), Colgate Sensitive (1,450 ppm F as sodium monofluorophosphate, 5% K citrate), Crest (fluoride-only toothpaste, 1,100 ppm F as NaF) and water (negative control). A second experiment was conducted with experimental dentifrices containing fluoride (NaF, 1,100 ppm F), 10% SrCl2, 5% KNO3 or 5% K citrate alone or the latter three combined with F. The samples were submitted to four cycles, alternating demineralization (cola, 10 min) and remineralization (artificial saliva, 1 h). Before and between cyclic de- and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 min). Erosive tissue loss was analyzed by profilometry. Data were analyzed by Kruskal-Wallis and Dunn’s tests (p < 0.05). The mean erosion depth (± SE, µm) was significantly less for Colgate Sensitive (0.04 ± 0.00), Sensodyne Original (0.06 ± 0.01) and Crest (0.07 ± 0.01) than for Sensodyne ProNamel (2.36 ± 0.25) or water (2.92 ± 0.24), which did not significantly differ from each other. Both F and the desensitizing agents alone reduced erosion, but no additive effect was found. In addition, the combination of F and KNO3 did not reduce erosion. These in vitro results suggest that the presence of fluoride or desensitizing substances in toothpastes, alone or in combination, can reduce erosion of enamel, but this is not valid for all the formulations.
Nosological Status of Endogenous Anxiety: ‘Anxious Thymopathy’ Revisited
Authors: López-Ibor J.J., Jr.
Published: February 2010

In 1950 LÓpez Ibor described a nosological entity called anxious thymopathy (‘timopatÍa ansiosa’). The origin of his description was the observation of recoveries of neurotic patients during psychotherapy which were not directly related to the psychodynamic process. Such a spontaneous fading of neurotic anxiety was suspected to be of an endogenous character. This led to the description of a vital anxiety, a mood disturbance similar to Schneider’s [1950] vital sadness present in endogenous depressions. Normal and pathological (vital) anxiety were thought to be different, vital anxiety having a biological origin, so that biological treatment was applied to it. In the course of the years, LÓpez Ibor came to the conclusion that anxious thymopathy was not an independent nosological entity, rather that vital (also called endothymic) anxiety was an element present in all forms of neurotic disorders integrated with personality and biographical factors. This research led to the concept of neuroses as mood disorders [LÓpez Ibor, 1966].
Th17 and Th1 T-Cell Responses in Giant Cell Arteritis
Authors: Deng Jiusheng , Younge Brian R. , Olshen Richard A. , Goronzy Jörg J. , Weyand Cornelia M.
Published: February 2010

Background—

In giant cell arteritis (GCA), vasculitic damage of the aorta and its branches is combined with a syndrome of intense systemic inflammation. Therapeutically, glucocorticoids remain the gold standard because they promptly and effectively suppress acute manifestations; however, they fail to eradicate vessel wall infiltrates. The effects of glucocorticoids on the systemic and vascular components of GCA are not understood.

Methods and Results—

The immunoprofile of untreated and glucocorticoid-treated GCA was examined in peripheral blood and temporal artery biopsies with protein quantification assays, flow cytometry, quantitative real-time polymerase chain reaction, and immunohistochemistry. Plasma interferon-γ and interleukin (IL)-17 and frequencies of interferon-γ-producing and IL-17-producing T cells were markedly elevated before therapy. Glucocorticoid treatment suppressed the Th17 but not the Th1 arm in the blood and the vascular lesions. Analysis of monocytes/macrophages in the circulation and in temporal arteries revealed glucocorticoid-mediated suppression of Th17-promoting cytokines (IL-1β, IL-6, and IL-23) but sparing of Th1-promoting cytokines (IL-12). In human artery-severe combined immunodeficiency mouse chimeras, in which patient-derived T cells cause inflammation of engrafted human temporal arteries, glucocorticoids were similarly selective in inhibiting Th17 cells and leaving Th1 cells unaffected.

Conclusions—

Two pathogenic pathways mediated by Th17 and Th1 cells contribute to the systemic and vascular manifestations of GCA. IL-17-producing Th17 cells are sensitive to glucocorticoid-mediated suppression, but interferon-γ-producing Th1 responses persist in treated patients. Targeting steroid-resistant Th1 responses will be necessary to resolve chronic smoldering vasculitis. Monitoring Th17 and Th1 frequencies can aid in assessing disease activity in GCA.
Age-Dependent Profile of Left-Sided Infective Endocarditis
Authors: López Javier , Revilla Ana , Vilacosta Isidre , Sevilla Teresa , Villacorta Eduardo , Sarriá Cristina , Pozo Eduardo , Rollán María Jesús , Gómez Itziar , Mota Pedro , San Román José Alberto
Published: February 2010

Background—

The influence of age on the main epidemiological, clinical, echocardiographic, microbiological, and prognostic features of patients with infective endocarditis remains unknown. We present the series with the largest numbers and range of ages of subjects to date that analyzes the influence of age on the main characteristics of patients with isolated left-sided infective endocarditis. Furthermore, this series is the first one in which patients have been distributed according to age quartile.

Methods and Results—

A total of 600 episodes of left-sided endocarditis consecutively diagnosed in 3 tertiary centers were stratified into age-specific quartiles and 107 variables compared between the different groups. With increasing age, the percentage of women, previous heart disease, predisposing disease (diabetes mellitus and cancer), and infection by enterococci and
Streptococcus bovis
also increased. Valvular insufficiency and perforation and
S
taphylococcus
aureus
infection were more common in younger patients. The therapeutic approach differed depending on patient age because of the growing proportion of older patients who only received medical treatment. Clinical course and hospital prognosis were worse in the older patients because of increased surgical mortality among them.

Conclusions—

Increasing age is associated with less valvular impairment (insufficiency and perforation), a more favorable microbiological profile, and increased surgical mortality among adults with left-sided infective endocarditis.
Predictors of Outcomes in Medically Treated Patients With Acute Coronary Syndromes After Angiographic Triage
Authors: Goto Kenji , Lansky Alexandra J. , Fahy Martin , Cristea Ecatarina , Feit Frederick , Ohman E. Magnus , White Harvey D. , Alexander Karen P. , Bertrand Michel E. , Desmet Walter , Hamon Martial , Mehran Roxana , Stone Gregg W.
Published: February 2010

Background—

Outcomes of patients presenting with acute coronary syndromes are improved with an early invasive approach; however, approximately one third of these patients are treated medically after angiographic screening. We sought to assess the predictors of adverse cardiac events in patients with acute coronary syndrome assigned to medical management.

Methods and Results—

This substudy of the Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trial included 4491 acute coronary syndrome patients treated medically after angiographic triage. Rates of bleeding and composite ischemia (death, myocardial infarction, revascularization) were compared among the 3 antithrombotic treatment arms. Composite ischemia occurred in 399 patients (9.5%) at 1 year. Treatment with bivalirudin glycoprotein IIb/IIIa inhibitors significantly reduced major bleeding at 30 days (2.5% bivalirudin monotherapy;
P
=0.005, 2.0% bivalirudin plus glycoprotein IIb/IIIa inhibitors;
P
=0.0002 versus 4.4% heparin with glycoprotein IIb/IIIa inhibitors). Composite ischemic events at 1 year were not significantly different in the 3 groups (bivalirudin monotherapy, 9.6%; bivalirudin plus glycoprotein IIb/IIIa inhibitors, 9.7%; heparin plus glycoprotein IIb/IIIa inhibitors, 9.1%). Independent predictors of composite ischemia were mostly angiographic factors at 30 days, including jeopardy score and coronary ectasia, and at 1 year, including previous percutaneous coronary intervention, jeopardy score, coronary ectasia, and increasing number of diseased vessels.

Conclusions—

Among the ACUITY acute coronary syndrome patients treated medically after angiographic triage, bivalirudin therapy significantly reduced bleeding complications compared with heparin without any negative impact on ischemic outcomes at 1 year. The most powerful predictors of ischemic outcomes were angiographic rather than traditional clinical parameters, supporting the early use of angiographic screening in the moderate- and high-risk but medically treated acute coronary syndrome population.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00093158.
Age-Related Differences in Characteristics, Performance Measures, Treatment Trends, and Outcomes in Patients With Ischemic Stroke
Authors: Fonarow Gregg C. , Reeves Mathew J. , Zhao Xin , Olson DaiWai M. , Smith Eric E. , Saver Jeffrey L. , Schwamm Lee H.
Published: February 2010

Background—

Prior studies have suggested lower use of guideline-recommended therapy and worse poststroke outcomes in older patients. We sought to examine age-related differences in characteristics, performance measures, temporal trends, and early clinical outcomes for acute ischemic stroke in a large contemporary cohort.

Methods and Results—

The relationships between age and clinical characteristics, performance measures, and in-hospital outcomes were analyzed in 502 036 ischemic stroke admissions from 1256 hospitals in the Get With the Guidelines–Stroke program from 2003 to 2009. Data were analyzed by age groups (<50, 50 to 59, 60 to 69, 70 to 79, 80 to 89, and ≥90 years) and with age as a continuous variable. Seven predefined performance measures and 2 summary measures were analyzed. Mean age of ischemic stroke patients was 71.0±14.6 years; 52.5% were women. Older patients were more likely to have a history of atrial fibrillation or hypertension and less likely to be black, Hispanic, or current/recent smokers. Although modest age-related differences in each individual performance measure were identified, there were substantial temporal improvements in performance measures from 2003 to 2009 in each age group, and many age-related treatment gaps were narrowed or eliminated over time. Older patients were less likely to be discharged home (adjusted odds ratio, 0.69; 95% confidence interval, 0.68 to 0.69) and more likely to die in hospital (adjusted odds ratio, 1.27; 95% confidence interval, 1.25 to 1.29) for each 10-year age increase.

Conclusions—

Older patients with ischemic stroke differ in clinical characteristics and experience higher in-hospital mortality than younger patients. Performance measure–based treatment rates improved substantially over time for ischemic stroke patients in all age groups, resulting in smaller age-related treatment gaps.
Mononuclear Phagocyte System Depletion Blocks Interstitial Tonicity-Responsive Enhancer Binding Protein/Vascular Endothelial Growth Factor C Expression and Induces Salt-Sensitive Hypertension in Rats
Authors: Machnik Agnes , Dahlmann Anke , Kopp Christoph , Goss Jennifer , Wagner Hubertus , van Rooijen Nico , Eckardt Kai-Uwe , Müller Dominik N. , Park Joon-Keun , Luft Friedrich C. , Kerjaschki Dontscho , Titze Jens
Published: February 2010

We showed recently that mononuclear phagocyte system (MPS) cells provide a buffering mechanism for salt-sensitive hypertension by driving interstitial lymphangiogenesis, modulating interstitial Na
+
clearance, and increasing endothelial NO synthase protein expression in response to very high dietary salt via a tonicity-responsive enhancer binding protein/vascular endothelial growth factor C regulatory mechanism. We now tested whether isotonic saline and deoxycorticosterone acetate (DOCA)-salt treatment leads to a similar regulatory response in Sprague-Dawley rats. Male rats were fed a low-salt diet and received tap water (low-salt diet LSD), 1.0% saline (high-salt diet HSD), or DOCA+1.0% saline (DOCA-HSD). To test the regulatory role of interstitial MPS cells, we further depleted MPS cells with clodronate liposomes. HSD and DOCA-HSD led to Na
+
accumulation in the skin, MPS-driven tonicity-responsive enhancer binding protein/vascular endothelial growth factor C–mediated hyperplasia of interstitial lymph capillaries, and increased endothelial NO synthase protein expression in skin interstitium. Clodronate liposome MPS cell depletion blocked MPS infiltration in the skin interstitium, resulting in unchanged tonicity-responsive enhance binding protein/vascular endothelial growth factor C levels and absent hyperplasia of the lymph capillary network. Moreover, no increased skin endothelial NO synthase protein expression occurred in either clodronate liposome–treated HSD or DOCA-salt rats. Thus, absence of the MPS-cell regulatory response converted a salt-resistant blood-pressure state to a salt-sensitive state in HSD rats. Furthermore, salt-sensitive hypertension in DOCA-salt rats was aggravated. We conclude that MPS cells act as onsite controllers of interstitial volume and blood pressure homeostasis, providing a local regulatory salt-sensitive tonicity-responsive enhancer binding protein/vascular endothelial growth factor C–mediated mechanism in the skin to maintain normal blood pressure in states of interstitial Na
+
and Cl
−
accumulation. Failure of this physiological extrarenal regulatory mechanism leads to a salt-sensitive blood pressure response.
Vasopressin V1a Receptor Polymorphism and Interval Walking Training Effects in Middle-Aged and Older People
Authors: Masuki Shizue , Mori Masayuki , Tabara Yasuharu , Miki Tetsuro , Sakurai Akihiro , Morikawa Mayuko , Miyagawa Ken , Higuchi Keiichi , Nose Hiroshi
Published: February 2010

We assessed whether single nucleotide polymorphism rs1042615 of the vasopressin V1a receptor altered the indices of lifestyle-related diseases in middle-aged and older people (mean±SD: 64±7 years), and, if so, whether it also altered the effects of interval walking training (IWT). CC, CT, and TT carriers of rs1042615 (42, 118, and 64 men, respectively; 113, 263, and 154 women, respectively) performed IWT. We included 5 sets of 3-minute fast walking at ≥70% peak aerobic capacity for walking and 3-minute slow walking at 40% peak aerobic capacity per day for ≥4 days per week for 5 months. Before IWT, the body mass index and diastolic blood pressure (DBP) for men were 25.1±0.3 kg/m
2
(mean±SE) and 84±1 mm Hg in TT, higher than the 23.6±0.4 kg/m
2
and 78±1 mm Hg in CC, respectively (
P
<0.01), differences that disappeared after IWT despite similar training achievement between groups (
P
>0.6). After IWT, body mass index and DBP decreased in TT (−0.9±0.1 kg/m
2
and −5±1 mm Hg, respectively), more than in CC (−0.5±0.1 kg/m
2
and 1±1 mm Hg, respectively;
P
<0.05), with a greater decrease in low-density lipoprotein cholesterol in TT than CC carriers (
P
<0.01). The decreases in DBP and low-density lipoprotein cholesterol were still greater in TT carriers even after adjustment for their pretraining values. On the other hand, for women, these parameters before IWT and their changes after IWT were similar among CC, CT, and TT carriers. Thus, polymorphism rs1042615 of the V1a receptor altered body mass index and DBP in middle-aged and older men and the training-induced responses of DBP and low-density lipoprotein cholesterol, whereas women did not show any of these responses.
Lagrangian Coherent Structures near a Subtropical Jet Stream
Authors: Tang Wenbo , Mathur Manikandan , Haller George , Hahn Douglas C. , Ruggiero Frank H.
Published: February 2010

Direct Lyapunov exponents and stability results are used to extract and distinguish Lagrangian coherent structures (LCS) from a three-dimensional atmospheric dataset generated from the Weather Research and Forecasting (WRF) model. The numerical model is centered at 19.78°N, 155.55°W, initialized from the Global Forecast System for the case of a subtropical jet stream near Hawaii on 12 December 2002. The LCS are identified that appear to create optical and mechanical turbulence, as evidenced by balloon data collected during a measurement campaign near Hawaii.
Genesis of Tropical Storm Eugene (2005) from Merging Vortices Associated with ITCZ Breakdowns. Part III: Sensitivity to Various Genesis Parameters
Authors: Kieu Chanh Q. , Zhang Da-Lin
Published: February 2010

In this study, a series of sensitivity simulations is performed to examine the processes leading to the genesis of Tropical Storm Eugene (2005) from merging vortices associated with the breakdowns of the intertropical convergence zone (ITCZ) over the eastern Pacific. This is achieved by removing or modifying one of the two vortices in the model initial conditions or one physical process during the model integration using the results presented in Parts I and II as a control run. Results reveal that while the ITCZ breakdowns and subsequent poleward rollup (through a continuous potential vorticity supply) provide favorable conditions for the genesis of Eugene, the vortex merger is the most effective process in transforming weak tropical disturbances into a tropical storm. The sensitivity experiments confirm the authors’ previous conclusions that Eugene would not reach its observed tropical storm intensity in the absence of the merger and would become much shorter lived without the potential vorticity supply from the ITCZ.

It is found that the merging process is sensitive not only to larger-scale steering flows but also to the intensity of their associated cyclonic circulations and frictional convergence. When one of the vortices is initialized at a weaker intensity, the two vortices bifurcate in track and fail to merge. The frictional convergence in the boundary layer appears to play an important role in accelerating the mutual attraction of the two vortices leading to their final merger. It is also found from simulations with different storm realizations that the storm-scale cyclonic vorticity grows at the fastest rate in the lowest layers, regardless of the merger, because of the important contribution of the convergence associated with the boundary layer friction and latent heating.
The Mutual Interaction between External Rossby Waves and Thermal Forcing: The Subpolar Regions
Authors: Orlanski Isidoro , Solman Silvina
Published: February 2010

The authors hypothesize a simple feedback mechanism between external Rossby waves and diabatic heating from convection. This mechanism could explain the large amplitude that external Rossby waves attain as they propagate to mid- and high latitudes. A series of experiments has been carried out with a core dynamic global spectral model. These simulations with the idealized atmospheric GCM and a simple parameterization of thermal forcing proportional to the low-level wave meridional velocity suggest that external Rossby waves can be enhanced by convection, which they themselves induce. It is shown that in the tropospheric upper levels the amplitude of the external waves can be twice as large with feedback as for a control simulation that does not allow feedback.
In Situ Chemical Characterization of Aged Biomass-Burning Aerosols Impacting Cold Wave Clouds
Authors: Pratt Kerri A. , Heymsfield Andrew J. , Twohy Cynthia H. , Murphy Shane M. , DeMott Paul J. , Hudson James G. , Subramanian R. , Wang Zhien , Seinfeld John H. , Prather Kimberly A.
Published: February 2010

During the Ice in Clouds Experiment–Layer Clouds (ICE-L), aged biomass-burning particles were identified within two orographic wave cloud regions over Wyoming using single-particle mass spectrometry and electron microscopy. Using a suite of instrumentation, particle chemistry was characterized in tandem with cloud microphysics. The aged biomass-burning particles comprised ∼30%–40% by number of the 0.1–1.0-μm clear-air particles and were composed of potassium, organic carbon, elemental carbon, and sulfate. Aerosol mass spectrometry measurements suggested these cloud-processed particles were predominantly sulfate by mass. The first cloud region sampled was characterized by primarily homogeneously nucleated ice particles formed at temperatures near −40°C. The second cloud period was characterized by high cloud droplet concentrations (∼150–300 cm−3) and lower heterogeneously nucleated ice concentrations (7–18 L−1) at cloud temperatures of −24° to −25°C. As expected for the observed particle chemistry and dynamics of the observed wave clouds, few significant differences were observed between the clear-air particles and cloud residues. However, suggestive of a possible heterogeneous nucleation mechanism within the first cloud region, ice residues showed enrichments in the number fractions of soot and mass fractions of black carbon, measured by a single-particle mass spectrometer and a single-particle soot photometer, respectively. In addition, enrichment of biomass-burning particles internally mixed with oxalic acid in both the homogeneously nucleated ice and cloud droplets compared to clear air suggests either preferential activation as cloud condensation nuclei or aqueous phase cloud processing.
Observed Climate–Snowpack Relationships in California and their Implications for the Future
Authors: Kapnick Sarah , Hall Alex
Published: February 2010

A study of the California Sierra Nevada snowpack has been conducted using snow station observations and reanalysis surface temperature data. Monthly snow water equivalent (SWE) measurements were combined from two datasets to provide sufficient data from 1930 to 2008. The monthly snapshots are used to calculate peak snow mass timing for each snow season. Since 1930, there has been an overall trend toward earlier snow mass peak timing by 0.6 days per decade. The trend toward earlier timing also occurs at nearly all individual stations. Even stations showing an increase in 1 April SWE exhibit the trend toward earlier timing, indicating that enhanced melting is occurring at nearly all stations. Analysis of individual years and stations reveals that warm daily maximum temperatures averaged over March and April are associated with earlier snow mass peak timing for all spatial and temporal scales included in the dataset. The influence is particularly pronounced for low accumulation years indicating the potential importance of albedo feedback for the melting of shallow snow. The robustness of the early spring temperature influence on peak timing suggests the trend toward earlier peak timing is attributable to the simultaneous warming trend (0.1°C decade−1 since 1930, with an acceleration in warming in later time periods). Given future scenarios of warming in California, one can expect acceleration in the trend toward earlier peak timing; this will reduce the warm season storage capacity of the California snowpack.
Regional Interdecadal Variability in Bias-Corrected Ocean Temperature Data*
Authors: Carson Mark , Harrison D. E.
Published: February 2010

Regional interdecadal variability, on subbasin to basin scales, is shown to be a robust feature of the post–World War II (WWII) historical temperature record, even after a recently proposed bias correction to XBT fall rates is applied. This study shows that the previously reported strong regional variability is generally unaffected by this correction, even though the interdecadal variability in the most recently published estimates of global ocean heat content is much reduced after a correction is applied. Following methods used in previous trend analysis work, estimates of interdecadal trends are calculated for individual regions of the global ocean where there are sufficient data. Spatial maps of temperature trends for the surface and three subsurface depths (50, 100, and 300 m) are presented, with both bias-corrected and uncorrected data trends at 100 and 300 m shown for comparison. In the upper two depths and at the surface, interdecadal variability is shown to be present and strong in most of the analysis regions. At 100 m, the differences between trends based on bias-corrected versus uncorrected data are small, and barely distinguishable for much of the ocean analyzed. There are more differences at 300 m between the two data treatments, but large-scale patterns are still present in the bias-corrected trends, especially where the trends are stronger.

Given the sampling issues discussed in previous works, the presence of strong interdecadal variability on smaller scales raises concerns that global interdecadal variability in the historical record still may not be properly resolved.
Loss of Significance and Multidecadal Variability of the Madden–Julian Oscillation
Authors: Suhas E. , Goswami B. N.
Published: February 2010

Change in significance and multidecadal variability of the Northern Hemispheric winter MJO during 1948–2006 is examined using NCEP–NCAR reanalysis data. Variation of the MJO power relative to a red background is estimated by isolating the MJO signal through frequency–wavenumber spectral analysis using a 10-yr sliding window. It is shown that during the period of study, the rate of increase of background power has been larger than the rate of increase of the MJO power, leading to a decreasing trend of significant MJO power. It is also found that a multidecadal variation rides on the decreasing trend of significant power of the MJO. Another finding is that the zonal mean component of the zonal wind at 200 hPa on a MJO time scale has a significant increasing trend. Both of the above trends are statistically significant at the 95% confidence level.

Energetics calculations in the wavenumber domain were carried out to understand why the significant MJO power is not increasing as fast as the red background. It is shown that long waves (wavenumbers 1–3, i.e., the MJO scale) lose energy to the zonal mean flow and the rate of kinetic energy gain by the zonal mean flow from the long waves has a linear increasing trend. Thus, while the MJO is also being energized by a warming ocean, it is losing increasingly more energy to the zonal mean flow, making the zonal mean more energetic while losing its own significance at the same time. It is found that the observed multidecadal variability of the significant MJO power has no relationship with other well-known multidecadal variability. However, the authors find that the multidecadal variability of the MJO and the rate of kinetic energy exchange between the zonal mean flow and long waves are closely linked, indicating that the observed multidecadal variability of the MJO is internally driven.
The Influence of Large-Scale Climate Variability on Winter Maximum Daily Precipitation over North America
Authors: Zhang Xuebin , Wang Jiafeng , Zwiers Francis W. , Groisman Pavel Ya
Published: February 2010

The generalized extreme value (GEV) distribution is fitted to winter season daily maximum precipitation over North America, with indices representing El Niño–Southern Oscillation (ENSO), the Pacific decadal oscillation (PDO), and the North Atlantic Oscillation (NAO) as predictors. It was found that ENSO and PDO have spatially consistent and statistically significant influences on extreme precipitation, while the influence of NAO is regional and is not field significant. The spatial pattern of extreme precipitation response to large-scale climate variability is similar to that of total precipitation but somewhat weaker in terms of statistical significance. An El Niño condition or high phase of PDO corresponds to a substantially increased likelihood of extreme precipitation over a vast region of southern North America but a decreased likelihood of extreme precipitation in the north, especially in the Great Plains and Canadian prairies and the Great Lakes/Ohio River valley.