bluuebunny/crossref_metadata_2025 huggingface dataset:
The High‐Frequency Responses of Australian Financial Futures to Unexpected Cash Rate Announcements*
Authors: LU XINSHENG , IN FRANCIS , KOU MINGTING
Published: August 2009

This study examines the high‐frequency responses of Australian financial futures to monetary surprises using intra‐day futures data. Using the event window method with tick data to control for the endogeneity between market interest rates and the cash rate, our empirical findings support the following. First, monetary policy announcements significantly impact not only short‐term interest rate futures but also longer‐term treasury security future markets. Second, the most significant responses of these markets occur in the event window that contains the policy announcement. Third, we also find that the monetary policy is not well anticipated by market participants until the Reserve Bank of Australia’s policy release.
Agonist efficacy and receptor desensitization: from partial truths to a fuller picture
Authors: Charlton Steven J
Published: August 2009

It has been demonstrated that the degree of agonist‐induced desensitization of the β2‐adrenoceptor is related to agonist efficacy (strength of signalling), whereby high‐efficacy agonists (e.g. formoterol) cause more phosphorylation and internalization of the receptor than low‐efficacy agonists (e.g. salmeterol). These early studies, however, used a protocol where agonists were matched for receptor occupancy rather than functional effect. In this issue of theBJP, Duringer and colleagues have extended these studies to compare the ability of agonists to cause desensitization at equi‐effective (cAMP signalling) concentrations rather than equal occupancy. Their data and conclusions are quite different from those previously described. After prolonged exposure, all the agonists caused a similar degree of desensitization, whereas a pulse protocol uncovered a greater loss of responsiveness with the low‐efficacy ligands. This is consistent with the notion that high‐efficacy agonists have ‘spare receptors’, and are therefore less sensitive to loss of receptors through desensitization. It also reflects experience in the clinic, where both formoterol and salmeterol show a similar early decline in bronchoprotection, after which their effects remain stable. These findings challenge the notion that high‐efficacy ligands always cause more functional desensitization.
Stimulation of cardiac β‐adrenoceptors targets connexin 43
Authors: Boengler Kerstin
Published: August 2009

Connexin 43 (Cx43) is the major protein of cardiac ventricular gap junctions and is crucial to cell–cell communication and cardiac function. The protein level of Cx43 is reduced in patients with heart failure or dilated cardiomyopathy (DCM), pathophysiological conditions often associated with arrhythmias. As catecholamines are often increased in cardiac diseases, Salameh et al., in this issue of the BJP, investigated the effect of β‐adrenoceptor stimulation of neonatal cardiomyocytes on Cx43 expression and found increased Cx43 mRNA and protein levels following 24 h stimulation. Up‐regulation of Cx43 was associated with phosphorylation of mitogen‐activated protein kinases and translocation of transcription factors into the nucleus. In patients with DCM, a situation often associated with desensitization of the β‐adrenoceptor system, Cx43 expression was reduced. The characterization of the signal transduction pathways involved in Cx43 expression and intracellular localization in human myocardium in vivo is a promising target for the development of new anti‐arrhythmic strategies.
Agonism and allosterism: the pharmacology of the free fatty acid receptors FFA2 and FFA3
Authors: Milligan Graeme , Stoddart Leigh A. , Smith Nicola J.
Published: August 2009

The free fatty acid receptors FFA2 and FFA3 are recently de‐orphanized G protein‐coupled receptors that share a group of short‐chain free fatty acids as endogenous ligands. The expression of FFA2 and FFA3 by immune cells, in parts of the gastro‐intestinal tract and by white adipocytes has suggested their potential as therapeutic targets in conditions including inflammation and obesity. However, although FFA2 and FFA3 display distinct structure–activity relationships for stimulation by short‐chain free fatty acids, the overlap between these endogenous agonists and the lack of synthetic small molecule ligands that display selectivity between these two receptors has, until recently, hindered efforts to resolve their individual functions. Recently, chloro‐α‐(1‐methylethyl)‐N‐2‐thiazolylbenzeneacetamide has been described as an FFA2 selective ago‐allosteric ligand, not only being a direct agonist but also acting as a positive allosteric modulator of the function of short‐chain free fatty acids at FFA2. Mutation of a pair of key arginine residues near the top of transmembrane domains V and VII of both FFA2 and FFA3 eliminates the function of short‐chain free fatty acids but is without effect on the direct agonist action of chloro‐α‐(1‐methylethyl)‐N‐2‐thiazolylbenzeneacetamide at FFA2, confirming the distinct nature of the binding site of the ago‐allosteric regulator from the orthosteric binding site for free fatty acids. An understanding of structure–activity relationships for ligands related to chloro‐α‐(1‐methylethyl)‐N‐2‐thiazolylbenzeneacetamide is likely to provide greater insight into the mode of action and site of binding of this ligand, but further FFA2 and FFA3 selective ligands, preferably with higher potency/affinity, will be required to fully explore the physiological function of these receptors.
Analysing Production Technology and Risk in Organic and Conventional Dutch Arable Farming using Panel Data
Authors: Gardebroek Cornelis , Chavez María Daniela , Lansink Alfons Oude
Published: August 2009

This paper compares the production technology and production risk of organic and conventional arable farms in the Netherlands. Just–Pope production functions that explicitly account for output variability are estimated using panel data of Dutch organic and conventional farms. Prior investigation of the data indicates that within variation of output is significantly higher for organic farms, indicating that organic farms face more output variation than conventional farms. The estimation results indicate that in both types of farms, unobserved farm‐specific factors like management skills and soil quality are important in explaining output variability and production risk. The results further indicate that land has the highest elasticity of production for both farm types. Labour and other variable inputs have significant production elasticities in the case of conventional farms and other variable inputs in the case of organic farms. Manure and fertilisers are risk‐increasing inputs on organic farms and risk‐reducing inputs on conventional farms. Other variable inputs and labour are risk increasing on both farm types; capital and land are risk‐reducing inputs.
Do Nutrition Claims Matter to Consumers? An Empirical Analysis Considering European Requirements
Authors: Stranieri Stefanella , Baldi Lucia , Banterle Alessandro
Published: August 2009

EU Regulation 1924/2006 introduced a European legal framework for nutrition messages for food product labels. The study analyses consumer interest towards nutrition labelling and claims, and examines the information consumers consider important during their purchasing decisions, and the main characteristics of those consumers interested in nutrition claims and nutrition labelling use. A total of 1,025 northern Italian consumers were surveyed. We estimate one binary logit model to investigate the use of nutrition labelling, and seven other ordinal regression models to analyse consumer interest towards nutrition claims and labelling. Consumers who use nutrition labelling have characteristics different from those who use nutrition claims. Consumers using nutrition labelling show a marked interest in food safety concerns, use experts as their source of information and have specific dietary habits. For consumers concerned about nutrition claims, the survey shows significant links with attributes influencing purchasing behaviour, such as price, brand, certification, etc. Socio‐demographic characteristics are statistically significant and show a positive link with age, gender and a negative linkage with income.
Inflammation, Immunity, and Vaccines for Helicobacter pylori
Authors: D’Elios Mario M. , Andersen Leif P.
Published: August 2009

Helicobacter pylori infects almost half of the population worldwide and represents the major cause of gastroduodenal diseases, such as duodenal and gastric ulcer, gastric adenocarcinoma, autoimmune gastritis, and B‐cell lymphoma of mucosa‐associated lymphoid tissue. Helicobacter pylori induces the activation of a complex and fascinating cytokine and chemokine network in the gastric mucosa. Different bacterial and environmental factors, other concomitant infections, and host genetics may influence the balance between mucosal tolerance and inflammation in the course of H. pylori infection. An inverse association between H. pylori prevalence and the frequencies of asthma and allergies was demonstrated, and the neutrophil activating protein of H. pylori was shown to inhibit the allergic inflammation of bronchial asthma. During the last year, significant progress was made on the road to the first efficient vaccine for H. pylori that will represent a novel and very important bullet against both infection and gastric cancer.
Helicobacter pylori Infection in Pediatrics
Authors: Kindermann Angelika , Lopes Ana I.
Published: August 2009

This review summarizes the articles published on Helicobacter pylori infection in children between April 2008 and March 2009. Recent evidence highlights the decreasing prevalence trend of H. pylori infection and supports both intrafamilial and extrafamilial transmission. The association with various symptoms is still being debated. Interestingly, H. pylori infection seems inversely associated with allergic diseases. Monoclonal stool antigen tests are widely used and accurate for the diagnosis of H. pylori infection, but less accurate in young children. The new biprobe real‐time PCR assay applied to stools showed a poor sensitivity in children. Using the urea hydrolysis rate next to the delta over baseline values, the 13C‐urea breath test provides excellent results for all age children, even for young children. Treatment of H. pylori infection remains a challenge, considering suboptimal efficacy of current therapy. Among emerging alternatives, sequential treatment appears promising. The adjunction of probiotics to conventional regimens, although eliciting great interest, has shown limited therapeutic benefit.
Utilization, Diagnosis, Treatment and Cost of Migraine Treatment in the Emergency Department
Authors: Friedman Deborah , Feldon Steven , Holloway Robert , Fisher Susan
Published: August 2009

Objective.— To determine the percentages of patients receiving migraine‐specific therapy and to estimate the rate of unnecessary neuroimaging studies in the emergency department (ED).

Methods.— A retrospective study was conducted analyzing medical records and hospital charge data of ED visits for migraine during 2005 in 2 university‐affiliated hospitals. Following a preliminary review of 23 randomly selected ED charts selected to determine the reliability of the coding process, 172 other charts were selected to include 1 visit per patient with a primary discharge diagnosis code of 346.0, 346.1, or 346.9. The diagnosis of migraine was confirmed using predefined criteria. Demographic information, treatment strategies, laboratory and neuroimaging tests, response to therapy, discharge planning, and charge data were evaluated.

Results.— Of 156 patients with completed visits, neuroimaging studies were performed in 36 patients (23%), and only 4 patients had no documented justification for obtaining imaging studies. Seventy‐eight patients (50%) had a potential contraindication to receiving migraine‐specific therapy. Nine patients (11.5% of eligible patients) received migraine‐specific therapy. Most patients were treated with a combination of parenteral antiemetics, narcotics, or ketorolac.

Conclusion.— This analysis supports previous studies indicating the underutilization of migraine‐specific treatment in the ED, and suggests that the ED is generally used as a “last resort” when the patient's home medication fails. Because of various contraindications, migraine‐specific medications may not be a treatment option in up to 50% of patients seen in the ED. Although almost all of the neuroimaging studies were justified, the radiology charges were a major contributing factor to the overall financial burden of emergency migraine care.
Noninvasive CBV Measurements During Epilepsy Using Multichannel NIRS
Authors: Watanabe Eiju , Mayanagi Yoshiaki
Published: August 2009

Purpose: Cerebral blood volume (CBV) was measured noninvasively during an epileptic seizure to localize the focus using near‐infrared spectroscopy (NIRS).

Methods: In nine patients with intractable epilepsy (eight temporal and one parietal lobe), seizures were induced by bemegride. CBV was measured with an 8‐channel NIRS (1 Hz). The ictal single‐photon‐emission computed tomography (SPECT) also was evaluated.

Results: In all of the cases, CBV increased for 20–50 s on the same side as the focus within 2 s after the onset of seizures, compatible with the EEG and ictal SPECT findings.

Conclusions: NIRS is valid for the localization of the focus in epilepsy.
Effects of Antiepileptie Drugs on Seizure Thresholds in the Rat Kindling Model of Temporal Lobe Epilepsy
Authors: Morimoto Kiyoshi , Sato Hitoshi , Watanabe Takemi , Hirao Toru , Sato Keiko , Sato Soichiro , Yamada Norihito
Published: August 2009

Purpose: To determine the antiepileptic profiles of antiepileptic drugs (AEDs), we compared the effects of various AEDs, including phenytoin (PHT), carbamazepine (CBZ), valproate (VPA), and diazepam (DZP), on seizure thresholds in the rat kindling model of temporal lobe epilepsy.

Methods: Male Sprague‐Dawley rats were used. A tripolar electrode was implanted into the amygdala under pentobarbital anesthesia. All rats underwent daily kindling stimulation (100 Hz, 2 s) until stable generalized seizures were induced. The generalized seizure‐triggering threshold (GST) was then determined for each rat by the application of stimulation, which increased in intensity by 50 μA steps at intervals of 15 min. After intraperitoneal administration of PHT (180 mg/kg), CBZ (40 mg/kg), VPA (200 mg/kg), or DZP (2 mg/kg), electrical stimulation at the intensity of the GST, or 2 or 3 times the GST, was delivered to the amygdala, and reversal of the anticonvulsant effects was measured.

Results: All AEDs had potent anticonvulsant effects on amygdala‐kindled seizures induced by stimulation at the GST. After treatment with PHT and CBZ, when the stimulus intensity was increased to 2 or 3 times the GST, the anticonvulsant effects were completely eliminated. In contrast, the effects of VPA were partially reversed and those of DZP were only slightly reversed by increases in the stimulus intensity.

Conclusions: These findings suggest that the prinicipal mechanism for the anticonvulsant effects of PHT and CBZ, which act primarily on voltage‐sensitive Na+ channels, is the significant increase of seizure thresholds in epileptogenic foci. In our previous study, lamotrigine had the same effects as PHT and CBZ on seizure thresholds. In contrast, the fundamental profile of VPA and DZP, which enhance a‐aminobutyric acid (GABA)/benzodiazepine (BZD) systems, differs from that of PHT/CBZ‐type AEDs, and the main mechanism for the anticonvulsant effects of these two drugs is blockade of seizure propagation and generalization. This conclusion is consistent with our recent findings for tiagabine (a selective GABA uptake inhibitor) in the kindling model (Morimoto et al. Epilepsia 1997;38:966).
Development of Acoustic Priming‐Induced Abnormal Excitation in the Hippocampus of the Noda Epileptic Rat (NER)
Authors: Iida Koji , Sasa Masashi , Hanaya Ryosuke , Akimitsu Tomohide , Seri‐kawa Tadao , Noda Atsushi , Ishihara Kumatoshi , Arita Kazunori , Kurisu Kaoru
Published: August 2009

Purpose: The Noda epileptic rat (NER), which was found in a colony of Crj:Wistar rats, shows spontaneous tonicxlonic convulsions at a frequency of approximately once per 30 h. However, weekly applied acoustic priming consistently induces tonic‐clonic convulsion with sound stimuli. When NERs were given sound stimuli (95 dB, 8 kHz, 30 s) weekly from age 3 weeks, the percentage of animals with audiogenic seizures increased with age and was 100% after age 9 weeks. The audiogenic‐response score to quantify the intensity of seizure responses also increased with age. Frontal cortical and hippocampal electroencephalograms (EEGs) showed low‐voltage spike‐and‐wave complexes during tonic convulsions, which evolved into high‐amplitude spike‐ or polyspike‐and‐wave complexes during clonic convulsion. Immediately after cessation of the seizures, the EEG showed a flattening or diffuse slowing. To elucidate the development of the seizure induction by acoustic priming, we examined the epileptiform discharges in the in‐terictal EEG as a function of age.

Methods: The acoustic priming was applied to NERs from age 7 to 35 weeks. Cortical and hippocampal EEGs were recorded weekly during the interictal stage for 15 min after a 15‐min habituation by using implanted electrodes.

Results: Sporadic spikes were observed predominantly in the hippocampus with age, although they were rarely synchronized in the cortex. Hippocampal spikes were observed in two (33.3%) of six animals at age 7–10 weeks, 23 (82.4%) of 28 animals at age 11–15 weeks, 12 (85.7%) of 14 animals at age 16–19 weeks, and 21 (100%) of 21 animals at age >20 weeks. This development of abnormal hippocampal discharges with acoustic priming was in line with the development of convulsive seizures.

Conclusions: Development of hippocampal excitation induced by acoustic priming is thought to lead to the induction of convulsive seizures in the NERs.
EVIDENCE FOR IMPACTS OF NONINDIGENOUS MACROALGAE: A META‐ANALYSIS OF EXPERIMENTAL FIELD STUDIES1
Authors: Thomsen Mads S. , Wernberg Thomas , Tuya Fernando , Silliman Brian R.
Published: August 2009

Invasions by nonindigenous macroalgal species (NIMS) potentially cause severe impacts on native species. We conducted a meta‐analysis of 18 field‐based manipulative experiments to quantify the direction and magnitude of impacts (Hedges effect sized, hereafter ES). We found significant small‐to‐medium negative effects on “macrophyte abundance” (cover, biomass of native taxa; EScumulative = −0.30) and medium‐to‐large negative effects on “macrophyte assemblages” (richness, diversity, total abundance; EScumulative = −0.70). In contrast, EScumulativewere not significant for “macrophyte processes” (growth, mortality; EScumulative = −0.39), “animal abundance” (densities; EScumulative = −0.13), or “animal assemblages” (richness, diversity; EScumulative = 0.75). The nonsignificant effect sizes were characterized by low sample sizes and should be interpreted with caution. Three study‐specific effect sizes were particularly large (<−2.0), showing that, in specific cases, impacts can be highly negative. From a conservation perspective, focus could be on such worst‐case scenarios. Still, the reported EScumulativeare likely biased toward larger effects because only the most conspicuous NIMS have been tested and because nonsignificant results are less likely to be published. To better understand the impacts of NIMS, more manipulative experiments are needed, testing more species and under contrasting environmental conditions. Future studies should include procedural control treatments and report the abundance of the NIMS to avoid ambiguous interpretations. In conclusion, current experimental evidence shows that NIMS have, on average, small‐to‐large negative impacts on native plant species and assemblages. It is possible that these effects can result in severe consequences when accumulated over long time periods and large spatial scales.
DISTRIBUTION OF ALGAL EPIPHYTES ACROSS ENVIRONMENTAL GRADIENTS AT DIFFERENT SCALES: INTERTIDAL ELEVATION, HOST CANOPIES, AND HOST FRONDS1
Authors: Longtin Caroline M. , Scrosati Ricardo A. , Whalen Gillian B. , Garbary David J.
Published: August 2009

Understanding epiphyte distribution in coastal communities is important because these organisms affect many others directly or indirectly. Yet, their distribution has been considerably less studied than that of their hosts and other primary‐space holders. Identifying major sources of variation in epiphyte abundance is thus still a need. Environmental gradients help predict species distribution and are pervasive on marine shores. In this study, we test the notion that environmental gradients across intertidal elevation, throughout host canopies, and along host fronds explain a large variation in the abundance of sympatric epiphytes. Our model system was the assemblage ofAscophyllum nodosum(L.) Le Jol. and its epiphytesVertebrata lanosa(L.) T. A. Chr. [=Polysiphonia lanosa(L.) Tandy],Elachista fucicola(Velley) Aresch., andPylaiella littoralis(L.) Kjellm. On the coast of Nova Scotia (Canada), we found evidence of a spatial segregation among these species at almost all scales. While the red epiphyteV. lanosawas more common at high‐ and midintertidal elevations (peaking at midelevations) and on middle segments of host fronds, the brown epiphytesE. fucicolaandP. littoraliswere more common at low elevations and restricted to distal segments of host fronds. Canopy habitat affected abundance only forV. lanosa, which was more common within the host canopy than on its periphery at midelevations. Since the studied gradients are related to predictable changes in abiotic factors, the identification of likely causes behind the observed patterns was facilitated. Our study ends by proposing abiotic and biotic factors that deserve priority in the experimental testing of the forces structuring this assemblage.
Variability on red blood cell transfusion practices among Brazilian neonatal intensive care units
Authors: Dos Santos Amélia M.N. , Guinsburg Ruth , Procianoy Renato S. , Sadeck Lílian dos S. R. , Netto Abimael Aranha , Rugolo Ligia M. , Luz Jorge H. , Bomfim Olga , Martinez Francisco E. , De Almeida Maria Fernanda B.
Published: August 2009

BACKGROUND: Guidelines for red blood cell (RBC) transfusions exist; however, transfusion practices vary among centers. This study aimed to analyze transfusion practices and the impact of patients and institutional characteristics on the indications of RBC transfusions in preterm infants.

STUDY DESIGN AND METHODS: RBC transfusion practices were investigated in a multicenter prospective cohort of preterm infants with a birth weight of less than 1500 g born at eight public university neonatal intensive care units of the Brazilian Network on Neonatal Research. Variables associated with any RBC transfusions were analyzed by logistic regression analysis.

RESULTS: Of 952 very‐low‐birth‐weight infants, 532 (55.9%) received at least one RBC transfusion. The percentages of transfused neonates were 48.9, 54.5, 56.0, 61.2, 56.3, 47.8, 75.4, and 44.7%, respectively, for Centers 1 through 8. The number of transfusions during the first 28 days of life was higher in Center 4 and 7 than in other centers. After 28 days, the number of transfusions decreased, except for Center 7. Multivariate logistic regression analysis showed higher likelihood of transfusion in infants with late onset sepsis (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.8‐4.4), intraventricular hemorrhage (OR, 9.4; 95% CI, 3.3‐26.8), intubation at birth (OR, 1.7; 95% CI, 1.0‐2.8), need for umbilical catheter (OR, 2.4; 95% CI, 1.3‐4.4), days on mechanical ventilation (OR, 1.1; 95% CI, 1.0‐1.2), oxygen therapy (OR, 1.1; 95% CI, 1.0‐1.1), parenteral nutrition (OR, 1.1; 95% CI, 1.0‐1.1), and birth center (p < 0.001).

CONCLUSIONS: The need of RBC transfusions in very‐low‐birth‐weight preterm infants was associated with clinical conditions and birth center. The distribution of the number of transfusions during hospital stay may be used as a measure of neonatal care quality.
Some Problems of and Futures for Urban Sociology: Toward a Sociology of Settlements
Authors: Gans Herbert J.
Published: August 2009

Forty years ago, Manuel Castells asked whether urban sociology had a subject matter and whether the term urban still had meaning—and this article reopens these and related questions. It also wonders why today's American urban sociology has concentrated on cities, especially big ones, concurrently virtually ignoring the three other types of communities—suburbs, towns, and rural areas—in which a majority of Americans live and work. Further, it argues that this four–community typology is logically dubious and empirically obsolete. If the field were redefined as a sociology of settlements, analytically more logical and substantively more relevant typologies could be developed. Another politically and organizationally more realistic alternative would split the field into four: a sociology of the city and one concentrating on other settlements, with a third field devoted to community studies, and the fourth to spatial sociology.
Why the Community Reinvestment Act Cannot be Blamed for the Subprime Crisis
Authors: Aalbers Manuel B.
Published: August 2009

It has  become common practice—and in particular, but not exclusively, in conservative media—to blame the Community Reinvestment Act (CRA) of 1977 for the U.S. subprime mortgage and foreclosure crisis that triggered the global financial crisis. It is argued that the CRA forced lenders to give mortgage loans to high–risk borrowers. This is nonsense for at least five reasons.
Time and Risk Diversification in Real Estate Investments: Assessing the Ex Post Economic Value
Authors: Fugazza Carolina , Guidolin Massimo , Nicodano Giovanna
Published: August 2009

Welfare gains to long‐horizon investors may derive from time diversification that exploits nonzero intertemporal return correlations associated with predictable returns. Real estate may thus become more desirable if its returns are negatively serially correlated. While it could be important for long‐horizon investors, time diversification has been mostly investigated in asset menus without real estate and focusing on in‐sample experiments. This article evaluates, ex post, the out‐of‐sample gains from diversification when equity real estate investment trusts (REITs) belong to the investment opportunity set. We find that diversification into REITs increases both the Sharpe ratio and the certainty equivalent of wealth for all investment horizons and for both classical and Bayesian (who account for parameter uncertainty) investors. The increases in Sharpe ratios are often statistically significant. However, the out‐of‐sample average Sharpe ratio and realized expected utility of long‐horizon portfolios are frequently lower than that of a one‐period portfolio, which casts doubt on the value of time diversification.
Financial Constraints, Liquidity Management and Investment
Authors: Riddiough Timothy J. , Wu Zhonghua
Published: August 2009

Investment and liquidity management are analyzed in a sector in which firms are exogenously cash constrained and empirical estimates of Tobin's q provide reliable measures of investment opportunity. Across the entire sector, we document substantial realized investment as well as high investment sensitivity to q. Investment is also sensitive to measures of financial market frictions, suggesting that constraints on retention of cash flow distort investment decisions. Liquidity is managed through dividend policy and access to short‐term bank finance, in which bank lines of credit smooth variation in available cash flow and accelerate investment. Using the Kaplan–Zingales method for measuring the degree of financial constraint, we identify substantial differences between investment and liquidity management policies of firms, in which more (less) financially constrained firms in our sample exhibit high (low) investment and liquidity management sensitivity to variables that measure financial market frictions.
QT Duration and Dispersion in Patients with Anomalous Origins of Coronary Arteries
Authors: KARGIN RAMAZAN , PALA SELCUK , AKÇAKOYUN MUSTAFA , ESEN ÖZLEM , DEMIRKIRAN AYKUT , KARAPINAR HEKIM , RASULZADA MUBARIZ , BITIGEN ATILA , EMIROGLU YUNUS , ÖZDEMIR NIHAL
Published: August 2009

Background: Coronary artery anomalies have been reported to show various symptoms ranging from chest pain and dyspnea to cardio‐respiratory arrest and sudden death. In this study, we attempted to assess the changes in QT interval duration and dispersion in anomalous origins of coronary arteries (AOCA).

Methods: Nineteen AOCA patients (mean age: 52 ± 11 years) and 30 healthy control subjects (mean age: 50 ± 12 years) were included in the study. Minimum and maximum corrected QT intervals, and corrected QT dispersion were calculated. The two groups were compared in terms of QT dispersion and QT duration.

Results: There was no difference between the two groups in terms of baseline demographic characteristics. Maximum corrected QT intervals (QTc max), minimum corrected QT intervals (QTc min), and corrected QT dispersion were higher in AOCA patients than controls (452 ± 38 vs 411 ± 25 ms [P = 0.0001], 402 ± 31 vs 383 ± 28 ms [P = 0.048], and 51 ± 30 vs 28 ± 12 ms [P = 0.001], respectively).

Conclusion: In the patients with anomalous origins of coronary arteries, QT dispersion that is an indicator of sudden cardiac death and arrhythmias frequency increased. QTc max, QTc min, and corrected QT dispersion are higher in patients with anomalous origin of the coronary artery than in control subjects.
Right Atrial Appendage Versus Bachmann's Bundle Stimulation: A Two‐Year Comparative Study of Electrical Parameters in Myotonic Dystrophy Type‐1 Patients
Authors: NIGRO GERARDO , RUSSO VINCENZO , POLITANO LUISA , CIOPPA NADIA DELLA , MANFREDI DONATELLA , CHIANESE RAFFAELE , DE CHIARA ANNABELLA , RAGO ANNA , ARENA GIULIA , PALLADINO ALBERTO , CALABRÒ RAFFAELE
Published: August 2009

Aim: We performed a two‐year follow‐up comparative study of long‐term electrical parameters between the right atrial appendage (RAA) and Bachmann's Bundle (BB) stimulation in myotonic dystrophy type 1 (MD1) patients.

Methods: Twenty‐five MD1 patients (18 men; age: 54 ± 13 years) with no difference in the electrical parameters between the RAA site and the BB region at implantation were randomized into two groups: in group I (13 patients; age: 52 ± 14 years; four women) the atrial lead was placed in the RAA and in group II (12 patients, age: 56 ± 12 years, three women) the lead was placed in the BB region. Measurements of electrical parameters were recorded at follow‐up intervals of 6 weeks and then 12 and 24 months postimplant.

Results: There was no statistically significant different in P‐wave amplitude, pacing threshold, and impedance values between the two groups at 6 weeks. At 24 months follow‐up, the intrinsic P‐wave amplitude was 2.05 ± 1.45 mV in the RAA group versus 3.28 ± 1.09 mV in the BB group (P < 0.05); the pacing threshold was 1.85 ± 1.8 V in the RAA group versus 0.50 ± 0.39 V in the BB group (P = 0.03); there were no differences in the atrial impedance between the two groups during the follow‐up period.

Conclusions: In a direct two‐year follow‐up comparison between the RAA and BB atrial pacing sites, we showed a statistically significant increased pacing threshold and decreased intrinsic P‐wave amplitude during RAA stimulation in MD1 patients.
Cryoablation at Growing Myocardium: No Evidence of Coronary Artery Obstruction or Intimal Plaque Formation Early and Late after Energy Application
Authors: KRIEBEL THOMAS , HERMANN HANS‐PETER , SCHNEIDER HEIKE , KROLL MAJA , SELLE JAKOB , OVERWAUL ANNA , SIGLER MATTHIAS , PAUL THOMAS
Published: August 2009

Background: Animal studies and clinical observations have demonstrated that radiofrequency current application at growing myocardium may result in coronary artery obstruction. Recently, cryoenergy has emerged as an effective alternative to radiofrequency ablation of arrhythmogenic substrates in pediatric patients. Up to now, there has been a lack of experimental data concerning the effects of cryoenergy application at growing myocardium.

Methods: During general anesthesia, selective coronary angiography of the right and left coronary artery was performed in 10 piglets (age: 6 weeks, body weight: 14–18 kg). Subsequently, cryoenergy was delivered at −75°C for 4 minutes using a 7‐F catheter with a 6‐mm‐tip electrode at the atrial aspect of the tricuspid valve annulus in a posterior and lateral position. Additional cryoenergy lesions were induced via a retrograde approach at the lateral and posterior atrial and ventricular aspect of the mitral valve annulus, respectively. Five animals were restudied after 48 hours by coronary angiography and intracoronary ultrasound and in the remaining five piglets after 3 and 6 months, respectively.

Results: Selective coronary angiography and intracoronary ultrasound studies did not demonstrate any evidence for coronary artery obstruction after 48 hours, 3 months, or 6 months after cryoenergy application. In addition, histological examinations of the cryolesions after 48 hours and after 6 months did not demonstrate any intimal proliferations of the coronary arteries, respectively.

Conclusions: By means of the present study, we did not observe any affection of the coronary arteries after cryoenergy application at growing myocardium in young piglets.
Low‐Loss Microwave Dielectrics Using Mg2(Ti1−xSnx)O4 (x=0.01–0.09) Solid Solution
Authors: Huang Cheng‐Liang , Chen Jhih‐Yong
Published: August 2009

Low‐loss ceramics having the chemical formula Mg2(Ti1−xSnx)O4 for x ranging from 0.01 to 0.09 have been prepared by the conventional mixed oxide route and their microwave dielectric properties have been investigated. X‐ray powder diffraction patterns indicate the corundum‐structured solid solutions for the prepared compounds. In addition, lattice parameters, which linearly increase from 8.4414 to 8.4441 Å with the rise of x from 0.01 to 0.09, also confirm the forming of solid solutions. By increasing x from 0.01 to 0.05, the Q×f of the specimen can be tremendously boosted from 173 000 GHz to a maximum 318 000 GHz. A fine combination of microwave dielectric properties (ɛr∼15.57, Q×f∼318 000 GHz at 10.8 GHz, τf∼−45.1 ppm/°C) was achieved for Mg2(Ti0.95Sn0.05)O4 ceramics sintered at 1390°C for 4 h. Ilmenite‐structured Mg(Ti0.95Sn0.05)O3 (ɛr∼16.67, Q×f∼275 000 GHz at 10.3 GHz, τf∼−53.2 ppm/°C) was detected as a second phase. The presence of the second phase, however, would cause no significant variation in the dielectric properties of the specimen, because the second phase properties are very similar to the primary phase. These unique properties, in particular, low ɛr and high Q×f, can be utilized as a very promising dielectric material for ultra‐high‐frequency applications.
Influence of repeated screw tightening on bacterial leakage along the implant–abutment interface
Authors: Do Nascimento Cássio , Pedrazzi Vinícius , Miani Paola Kirsten , Moreira Larissa Daher , De Albuquerque Junior Rubens Ferreira
Published: August 2009

Objectives: Bacterial penetration along the implant–abutment interface as a consequence of abutment screw loosening has been reported in a number of recent studies. The aim of this in vitro study was to investigate the influence of repeated tightening of the abutment screw on leakage of Streptococcus mutans along the interface between implants and pre‐machined abutments.

Materials and methods: Twenty pre‐machined abutments with a plastic sleeve were used. The abutment screws were tightened to 32 N cm in group 1 (n=10 – control) and to 32 N cm, loosened and re‐tightened with the same torque twice in group 2 (n=10). The assemblies were completely immersed in 5 ml of Tryptic Soy Broth medium inoculated with S. mutans and incubated for 14 days. After this period, contamination of the implant internal threaded chamber was evaluated using the DNA Checkerboard method.

Results: Microorganisms were found on the internal surfaces of both groups evaluated. However, bacterial counts in group 2 were significantly higher than that in the control group (P<0.05).

Conclusion: These results suggest that bacterial leakage between implants and abutments occurs even under unloaded conditions and at a higher intensity when the abutment screw is tightened and loosened repeatedly.
Response of osteoblast‐like SAOS‐2 cells to zirconia ceramics with different surface topographies
Authors: Hempel Ute , Hefti Thomas , Kalbacova Marie , Wolf‐Brandstetter Cornelia , Dieter Peter , Schlottig Falko
Published: August 2009

Objectives: Zirconia is a suitable biomaterial for use in medicine (stomatology, orthopaedics) due to its good biocompatibility and outstanding mechanical properties. This study compares the effect of (i) zirconia to the widely used titanium and (ii) zirconia with two different surface topographies (sandblasted and sandblasted/etched) on the adhesion, proliferation and differentiation of SAOS‐2 osteoblasts.

Methods: SAOS‐2 cells were cultured on either sandblasted or sandblasted/etched zirconia and compared with sandblasted/etched titanium. 2 and 24 h after plating, cell morphology was investigated by scanning electron microscope (SEM) and fluorescence imaging. At 24 and 48 h, cell number‐relevant parameters were determined. Alkaline phosphatase (ALP) activity and mineral accumulation were measured at days 8, 11, 15 and day 22 of culture, respectively.

Results: SEM and fluorescence images revealed a faster spreading as well as higher number of adherent cells after 24 h incubation on zirconia compared with titanium. Also, the cellular metabolic activity after 24 h and the proliferation rate after 48 h is higher with zirconia compared with titanium. Zirconia had a more pronounced effect compared with titanium on the differentiation of SAOS‐2 cells: ALP activity, an early differentiation marker increased earlier and mineralization, a late differentiation marker was increased. Only minor differences were found between zirconia with two different surface topographies; etched zirconia promoted slightly greater the differentiation of SAOS‐2 cells.

Conclusions: These data indicate that zirconia mediates a pronounced stronger effect on the adhesion, proliferation and differentiation compared with titanium; and that topographical differences of zirconia have minor effects on osteoblast biology.

To cite this article:
 Hempel U, Hefti T, Kalbacova M, Wolf‐Brandstetter C, Dieter P, Schlottig F. Response of osteoblast‐like SAOS‐2 cells to zirconia ceramics with different surface topographies. Clin. Oral Impl. Res. 21, 2010; 174–181. doi: 10.1111/j.1600‐0501.2009.01797.x
ORIGINAL ARTICLE: Maternal Circulating TNF‐α Levels are Highly Correlated with IL‐10 Levels, but not IL‐6 and IL‐8 Levels, in Women with Pre‐Eclampsia
Authors: Lewis David F. , Canzoneri Bernard J. , Wang Yuping
Published: August 2009

Problem  Several lines of evidence have shown that maternal cytokine levels of tumor necrosis factor‐α (TNF‐α), interleukin (IL)‐6, IL‐8, and IL‐10 were altered in women with pre‐eclampsia (PE) compared to those from normal pregnancies. In this study, we determined whether these cytokine levels are correlated before and after delivery in patients with PE.

Method of study  Venous blood was obtained from 50 women diagnosed with severe PE at the time of admission and 24 hr after delivery. Plasma concentrations for TNF‐α, IL‐6, IL‐8, and IL‐10 were measured by ELISA.

Results  There were no statistical differences for maternal levels of TNF‐α, IL‐6, IL‐8, and IL‐10 before and 24 hr postpartum. TNF‐α and IL‐10, but not IL‐6 and IL‐8, levels were significantly correlated before and 24 hr after delivery: TNF‐α: y = 19.963 + 0.953*x; r2 = 0.924; IL‐10: y = 10.521 + 1.113*x; r2 = 0.984, P < 0.001, respectively. Furthermore, TNF‐α levels were correlated with IL‐10 levels, but not with IL‐6 and IL‐8 levels.

Conclusion  The correlation patterns of TNF‐α with IL‐10 and TNF‐α with IL‐6 and IL‐8 suggest disparity in functional regulations between these cytokines in maternal circulation in PE.
Dermatology in the Darwin anniversary. Part 1: Evolution of the integument
Authors: Schempp Christoph , Emde Matthias , Wölfle Ute
Published: August 2009

The present review highlights the development of the integument and its adnexa from the primitive metazoans to man. The different stages of development represent independent, partially convergent evolutions rather than a continuous evolutionary line. The epidermis of the invertebrates (sponges, cnidaria, worms, echinoderms and arthropods) always consists of one layer of pluripotent cells. The barrier function of the integument at this level is achieved with physico‐chemical barriers, toxin production, fortification of the epidermis in the form of a cuticula, a syncytium or a neodermis. The lower vertebrates (cyclostoma, fishes and amphibians) have a stratified epidermis harboring many secretory cells. In terrestrial amphibians the outermost cell layer of the epidermis is cornified, and the secretory cells are relocated in the dermis. Terminal differentiation and cornification of the epidermis in the birds and mammals result in a more uniform shape of the epithelium. Stem cells are now restricted to some basal regions of the epithelium. In the mammals the glands are located in the deeper layers of the skin. In contrast to other vertebrate integuments the human skin does not possess specialized structures such as feathers, scales or coats. However, waiving specialization allows for unique universality of the human skin compared to other vertebrates.
Cholinergic and oxidative stress mechanisms in sudden infant death syndrome
Authors: Dick Anne , Ford Rodney
Published: August 2009

Aim: To determine whether biochemical parameters of cholinergic and oxidative stress function including red cell acetylcholinesterase (AChE), serum/plasma thyroglobulin, selenium, iron, ferritin, vitamins C, E, and A affect risk in apparent life‐threatening event (ALTE), sudden infant death syndrome (SIDS), and sudden unexpected death in infancy (SUDI). To assess these biochemical parameters as a function of age; and for influence of pharmacology and epidemiology, including infant health, care, and feeding practices.

Methods: A multicentre, case–control study with blood samples from 34 ALTE and 67 non‐ALTE (control) infants matched for age, and 30 SIDS/SUDI and four non‐SIDS/non‐SUDI (post‐mortem control) infants.

Results: Levels/activity of the biochemical parameters were not significantly different in ALTE vs. control infants, with the exception of higher vitamin C levels in the ALTE group (p = 0.009). In ALTE and control groups, AChE and thyroglobulin levels increased and decreased respectively from birth to attain normal adult levels from 6 months. Levels of iron and ferritin were higher in the first 6 month period for all infant groups studied, intersecting with vitamin C levels peaking around 4 months of age.

Conclusion: Lower AChE levels and higher combined levels of iron and vitamin C in the first 6 months of life may augment cholinergic and oxidative stress effect, particularly at the age when SIDS is most prevalent. This may contribute to risk of ALTE and SIDS/SUDI events during infancy.
Psychopathology among preterm infants using the Diagnostic Classification Zero to Three
Authors: Janssens A , Uvin K , Van Impe H , Laroche SMF , Van Reempts P , Deboutte D
Published: August 2009

Aim: To compare the prevalence of psychopathology in infants born preterm with matched full‐term infants at the corrected age of 1 year.

Methods: Between June 2003 and April 2005, a case‐control longitudinal cohort study was conducted at the neonatal unit of the University Hospital of Antwerp, Belgium. We prospectively enrolled 123 live‐born infants between 25 and 35 weeks of gestation and/or infants with a birth‐weight of <1500 g. Thirty full‐term infants were recruited among day care centres in the region. Diagnoses were based on the Diagnostic Classification Zero to Three (DC: 0–3), using the MacArthur Communicative Developmental Inventory Dutch version, Infant–Toddler Sensory Profile, Bayley Scales of Infant Development II, Parent Infant Relationship Global Assessment Scale and Functional Emotional Assessment Scale.

Results: At the (corrected) age of 12 months, 89 infants were eligible for follow‐up and complete data were available for 69 (77%) infants. Fifty‐four percentage of the preterm infants fulfilled one or more DC 0–3 diagnoses. Premature infants had significantly more diagnoses than full‐term infants on axis I, axis III and axis V of the DC: 0–3.

Conclusion: In this study, the prevalence of psychopathology was significantly higher among preterm infants in comparison with full‐term infants. This study did not confirm previous findings of higher rates of relationship disorders among preterm infants.
Effect of fatty acids added to the milk replacer on white scour and excretion of fatty acids in Holstein calves
Authors: OKADA Keiji , GOTO Yoshie , FURUKAWA Takehiro , IKUTA Kentaro , YASUDA Jun
Published: August 2009

In order to examine the relationship between white scour and fatty acids, we added fatty acids to the milk replacer. Twenty healthy Holstein calves were divided into 4 groups, five calves per group; a control group with no fortified fatty acid, and 3 groups fed either with oleic, stearic, or palmitic acid, respectively. The calves were fed milk replacer (5% of the calf's body weight) twice a day but the fatty acids (2 wt % of milk replacer) were added only once. The fecal and blood samples were obtained at 0, 12, 24, 36, and 48 h after feeding of the acids. All five calves in the palmitic acid group, and 3 out of 5 calves each in the stealic and the oleic acid groups had whitish feces after feeding fatty acid. The stearic acid group had a significantly elevated stearic acid concentration in the feces during 24–36 h compared to the pre‐feeding level. The fecal concentration of palmitic acid increased significantly at 24–36 h in the palmitic acid group. We concluded that the long‐chain saturated fatty acids are one of the causes of white scour in calves.
Development of olfactory epithelium in the human fetus: Scanning electron microscopic observations
Authors: Kimura Mitsuhiro , Umehara Tsuyoshi , Udagawa Jun , Kawauchi Hideyuki , Otani Hiroki
Published: August 2009

Aims:  Human olfactory epithelium becomes functional at birth, but prenatal development remains unclear. In the present study, we aimed to clarify the development of human olfactory epithelium using scanning electron microscopy (SEM).

Methods:  The development of human olfactory epithelium was observed in 24 externally normal fetuses, which were formalin‐fixed and long‐preserved, with a crown‐rump length (CRL) of 102–336 mm (gestational week 14–38). The olfactory mucosa in the superior wall of the nasal septum near the choana were dissected and observed under SEM. We examined the number of olfactory vesicles per unit area, diameter of olfactory vesicles, and number and length of cilia on olfactory vesicles.

Results:  At circa (ca) CRL 100 mm (ca 14 weeks), olfactory epithelium displayed several olfactory vesicles with 1–2 short cilia per unit area. At ca CRL 150 mm (ca 18 weeks), olfactory vesicles were present in small clusters, and cilia were longer. At CRL lager than 225 mm (ca 26 weeks), olfactory vesicles became located separately from each other, while length and number of cilia per olfactory vesicle were further increased.

Conclusion:  The present findings suggest that fetal olfactory epithelium becomes morphologically almost the same as that in adults in late gestation, much later than previously thought.