bluuebunny/crossref_metadata_2025 huggingface dataset:
Vulval vestibulitis: a common cause of dyspareunia?
Authors: Munday Pat , Green John , Randall Carina , Fox Deidre , Singh Maneesha , Ismailjee Fatima , Perreira Elizabeth
Published: March 2005

The prevalence of vulval vestibulitis was evaluated in a prospective observational study. Four hundred women from West Hertfordshire, 100 each from community family planning, antenatal, general practice and genitourinary clinics were investigated. Participants completed a questionnaire and were examined for vulval erythema and point tenderness. An algesiometer was also used to evaluate tenderness. The prevalence of vestibulitis varied from 2.9% to 9.8% depending on the stringency of diagnostic criteria and the method of ascertaining pain. Vulval vestibulitis cannot be accurately defined by current criteria, but superficial dyspareunia appears to be a frequent problem in the community in women consulting for unrelated matters.
Maternity care in the former Soviet Union
Authors: Chalmers Beverley
Published: March 2005

There are many projects to help reform maternity care in the former Soviet Union (FSU). Doctors and other health workers are visiting, conducting research in and offering clinical assistance to many such countries. Some understanding of the practices in these regions will help them prepare for, and plan, maternity reforms. This paper outlines key features of the maternity care systems in place in the FSU.
Time course of molecular responses of human skeletal muscle to acute bouts of resistance exercise
Authors: Bickel C. S. , Slade J. , Mahoney E. , Haddad F. , Dudley G. A. , Adams G. R.
Published: March 2005

Resistance exercise (RE) training, designed to induce hypertrophy, strives for optimal activation of anabolic and myogenic mechanisms to increase myofiber size. Clearly, activation of these mechanisms must precede skeletal muscle growth. Most mechanistic studies of RE have involved analysis of outcome variables after many training sessions. This study measured molecular level responses to RE on a scale of hours to establish a time course for the activation of myogenic mechanisms. Muscle biopsy samples were collected from nine subjects before and after acute bouts of RE. The response to a single bout was assessed at 12 and 24 h post‐exercise. Further samples were obtained 24 and 72 h after a second exercise bout. RE was induced by neuromuscular electrical stimulation to generate maximal isometric contractions in the muscle of interest. A single RE bout resulted in increased levels of mRNA for IGF binding protein‐4 (84%), MyoD (83%), myogenin (approximately threefold), cyclin D1 (50%), and p21‐Waf1 (16‐fold), and a transient decrease in IGF‐I mRNA (46%). A temporally conserved, significant correlation between myogenin and p21 mRNA was observed (r=0.70, P<or=0.02). The mRNAs for mechano‐growth factor, IGF binding protein‐5, and the IGF‐I receptor were unchanged by RE. Total skeletal muscle RNA was increased 72 h after the second serial bout of RE. These results indicate that molecular adaptations of skeletal muscle to loading respond in a very short time. This approach should provide insights on the mechanisms that modulate adaptation to RE and may be useful in evaluating RE training protocol variables with high temporal resolution.
Glucocorticoid adrenal steroids and glucocorticoid‐inducible kinase isoforms in the regulation of GluR6 expression
Authors: Strutz‐Seebohm Nathalie , Seebohm Guiscard , Shumilina Ekaterina , Mack Andreas F. , Wagner Hans‐Joachim , Lampert Angelika , Grahammer Florian , Henke Guido , Just Lothar , Skutella Thomas , Hollmann Michael , Lang Florian
Published: March 2005

Generation of memory is enhanced during stress, an effect attributed to stimulation of neuronal learning by adrenal glucocorticoids. The glucocorticoid‐dependent genes include the serum‐ and glucocorticoid‐inducible kinase SGK1. SGK1 is activated through the phosphatidylinositol 3 kinase (PI3‐kinase) pathway by growth factors such as insulin‐like growth factor‐1 (IGF1) or tumour growth factor β (TGF‐β). Previously, a fourfold higher expression of SGK1 has been observed in fast‐learning rats as compared with slow‐learning rats. The mechanisms linking glucocorticoids or SGK1 with neuronal function have, however, remained elusive. We show here that treatment of mice with the glucocorticoid dexamethasone (238 μg day−1 for 8–20 days) enhances hippocampal expression of GluR6. Immunohistochemistry reveals significantly enhanced GluR6 protein abundance at neurones but not at astrocytes in mice. Immunohistochemistry and patch clamp on hippocampal neurones in primary culture reveal upregulation of GluR6 protein abundance and kainate‐induced currents following treatment with dexamethasone (1 μm) and TGF‐β (1 μm). In Xenopus oocytes expressing rat GluR6, coexpression of SGK1 strongly increases glutamate‐induced current at least partially by increasing the abundance of GluR6 protein in the plasma membrane. The related kinases SGK2 and SGK3 similarly stimulate GluR6, but are less effective than SGK1. The observations point to a novel mechanism regulating GluR6 which contributes to the regulation of neuronal function by glucocorticoids.
AT1-receptor antagonism reverses the blood pressure elevation associated with diet-induced obesity
Authors: Boustany Carine M , Brown David R. , Randall David C. , Cassis Lisa A
Published: March 2005

Previous studies in our laboratory demonstrated that rats exhibiting obesity in response to a moderately high-fat (MHF) diet developed hypertension associated with activation of the local and systemic renin-angiotensin system. In this study, we examined the effect of the angiotensin type 1 (AT1)-receptor antagonist, losartan, on blood pressure in obesity-prone (OP) and obesity-resistant (OR) rats fed a MHF diet. Using telemetry monitoring, we characterized the evolution of blood pressure elevations during the development of obesity. Male Sprague-Dawley rats were implanted with telemetry transducers for chronic monitoring of blood pressure, and baseline measurements were obtained. Rats were then switched to the MHF diet (32% kcal as fat) and were segregated into OP and OR groups at week 5. At week 9 on the MHF diet, OP rats exhibited significantly greater 24-h mean arterial blood pressure compared with OR rats (OP: 105 ± 4 mmHg, OR: 96 ± 2 mmHg; P < 0.05). Elevations in blood pressure in OP rats were manifest as an increase in systolic pressure. Administration of losartan to all rats at week 9 resulted in a reduction in blood pressure; however, losartan had the greatest effect in OP rats (percent decrease in mean arterial pressure by losartan; OP: 19 ± 4, OR: 10 ± 2%; P < 0.05). These results demonstrate that elevations in blood pressure occur subsequent to established obesity in rats fed a high-fat diet. Moreover, these results demonstrate the ability of losartan to reverse the blood pressure increase from diet-induced obesity, supporting a primary role for the renin-angiotensin system in obesity-associated hypertension.
Preconditioning with 1,25-Dihydroxyvitamin D3 Protects against Subsequent Ischemia-Reperfusion Injury in the Rat Kidney
Authors: Kim Young Ok , Li Can , Sun Bo Kyung , Kim Jung Sim , Lim Sun Woo , Choi Bun Soon , Kim Yong Soo , Kim Jin , Bang Byung Kee , Yang Chul Woo
Published: March 2005

Background/Aim: Induction of heat shock protein 70 (HSP70) is important in the tolerance of subsequent ischemia-reperfusion (I/R) injury. The aim of this study was to evaluate the effect of HSP70 induction by 1,25-dihydroxyvitamin D3 (VD3) on subsequent I/R injury in rats. Methods: HSP70 was induced in Sprague-Dawley rats by VD3 treatment for 7 days, and the effect of VD3 pretreatment on subsequent I/R injury was evaluated in terms of renal function, tubular necrosis score, tumor necrosis factor alpha mRNA expression, mitogen-activated protein kinase expression, and proliferating cell nuclear antigen expression. Results: VD3 treatment increased HSP70 expression which was localized to renal tubular cells in the outer medulla. Pretreatment with VD3 before I/R injury resulted in (1) decreased blood urea nitrogen and serum creatinine levels; (2) decreased tubular cell necrosis; (3) increased tubular cell proliferation as determined by proliferating cell nuclear antigen expression; (4) decreased tumor necrosis factor alpha mRNA expression, and (5) increased extracellular signal regulated protein kinase and decreased c-Jun N-terminal kinase expression. Conclusion: Our study demonstrates that VD3 is a nontoxic inducer of HSP70 and exerts a protective effect against subsequent I/R injury.
Activation of ATP-Binding Cassette Transporter A1 Transcription by Chromatin Remodeling Complex
Authors: Huuskonen Jarkko , Vishnu Meeta , Fielding Phoebe E. , Fielding Christopher J.
Published: March 2005

Objective—

Liver X receptor (LXR) regulates the transcription of ATP-binding cassette transporter A1 (ABCA1) by binding to the DR-4 promoter element as a heterodimer with retinoid X receptor (RXR). The role of chromatin remodeling complex in LXR or ABCA1 activation has not been established previously. In this study, we investigated the activation of ABCA1 by brahma-related gene 1 (BRG-1) and brahma, members of the SWI/SNF (mating type switching/sucrose nonfermenting) chromatin remodeling complex.

Methods and Results—

Overexpression of wild-type BRG-1 in SW-13 cells, but not a catalytically inactive mutant, increased ABCA1 mRNA levels determined by RT-PCR. These effects were enhanced by LXR and RXR agonists. In 293T (epithelial kidney cell line) and Hep3B (hepatocyte cell line) cells, small interfering RNA against BRG-1/brm also affected ABCA1 mRNA levels. Synergistic activation of ABCA1 was obtained after coexpressing BRG-1 and SRC-1, a coactivator of LXR. Luciferase assays showed that this activation of ABCA1 was dependent on the promoter DR-4 element. Coimmunoprecipitation and chromatin immunoprecipitation studies indicated that the mechanism of BRG-1–mediated activation of ABCA1 involved interaction of LXR/RXR with BRG-1 and binding of this complex to ABCA1 promoter.

Conclusions—

Catalytic subunits of SWI/SNF chromatin remodeling complex, BRG-1 and brahma, play significant roles in enhancing LXR/RXR–mediated transcription of ABCA1 via the promoter DR-4 element.
Sequencing of Chemotherapy and Radiation Therapy in Early-Stage Breast Cancer: Updated Results of a Prospective Randomized Trial
Authors: Bellon Jennifer R. , Come Steven E. , Gelman Rebecca S. , Henderson I. Craig , Shulman Lawrence N. , Silver Barbara J. , Harris Jay R. , Recht Abram
Published: March 2005

Purpose

The optimal integration of chemotherapy with radiation (RT) for patients with early-stage breast cancer remains uncertain. We present the long-term results of a prospective randomized trial to address this question.

Patients and Methods

Two hundred forty-four patients were randomly assigned after conservative breast surgery to receive 12 weeks of cyclophosphamide, doxorubicin, methotrexate, fluorouracil, and prednisone (CAMFP) before RT (CT-first) or after RT (RT-first). Median follow-up for surviving patients was 135 months.

Results

There were no significant differences between the CT-first and RT-first arms in time to any event, distant metastasis, or death. Sites of first failure were also not significantly different.

Conclusion

Among breast cancer patients treated with conservative surgery, there is no advantage to giving RT before adjuvant chemotherapy. However, this study does not have enough statistical power to rule out a clinically important survival benefit for either sequence.
Gasphasenkatalyse mit atomaren und Cluster‐Metall‐Ionen: ultimative “Single‐Site”‐Katalysatoren
Authors: Böhme Diethard K. , Schwarz Helmut
Published: March 2005

Gasphasenexperimente mithilfe moderner massenspektrometrischer Methoden geben detaillierte Einblicke in vielerlei Elementarprozesse. Reaktionen, denen vollständige Katalysezyklen unter thermischen Bedingungen zugrunde liegen, bilden den Schwerpunkt dieses Aufsatzes. Die hier aufgeführten Beispiele decken Aspekte der Katalyse ab, die zu so unterschiedlichen Gebieten wie der Atmosphärenchemie und der Oberflächenchemie gehören. Wir werden beschreiben, wie atomare und Cluster‐Metall‐Ionen den Transfer von Sauerstoffatomen, die Aktivierung von Bindungen und die Kupplung von Fragmenten ermöglichen. Zum Teil zeigt die idealisierte Gasphasenkatalyse mit Ionen ungeahnte Analogien zu verwandten chemischen Prozessen in Lösung oder in Feststoffen, und wir lernen die intrinsischen Vorgänge an Katalysatoren auf rein molekularer Ebene besser zu verstehen.
Organic and carbon aerogels from the NaOH‐catalyzed polycondensation of resorcinol–furfural and supercritical drying in ethanol
Authors: Wu Dingcai , Fu Ruowen , Yu Zhiquan
Published: March 2005

Organic aerogels and related carbon aerogels were prepared from the NaOH‐catalyzed polycondensation of resorcinol–furfural (RF) and supercritical drying in ethanol. The effect of the preparation conditions, including the RF concentration, molar ratio of resorcinol (R) to NaOH, and molar ratio of R to furfural, on the gelation time and bulk density was studied. The chemical structure of the organic aerogel was revealed by IR spectroscopy. The pyrolysis process of the organic aerogel was investigated by thermogravimetric analysis. According to characterizations of transmission electron microscopy and nitrogen adsorption, the organic and carbon aerogels we obtained had a three‐dimensional network that consisted of around 30‐nm particles, which defined numerous mesopores of less than 30 nm. As a result, the aerogels had high Brunauer–Emmett–Teller surface areas (698–753 m2/g) and large mesopore volumes (1.09–1.64 cm3/g). X‐ray diffraction characterization indicated that the carbon aerogel was more crystalline than activated carbon but less activated than graphite. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1429–1435, 2005
Hepatitis C is a risk factor for death after liver retransplantation
Authors: Pelletier Shawn J. , Schaubel Douglas E. , Punch Jeffrey D. , Wolfe Robert A. , Port Friedrich K. , Merion Robert M.
Published: March 2005

Retransplantation for liver allograft failure associated with hepatitis C virus (HCV) has been increasing due to nearly universal posttransplant HCV recurrence and has been demonstrated to be associated with poor outcomes. We report on the risk factors for death after retransplantation among liver recipients with HCV. A retrospective cohort of liver transplant recipients who underwent retransplantation between January 1997 and December 2002 was identified in the Scientific Registry of Transplant Recipients database. Cox regression was used to assess the relative effect of HCV diagnosis on mortality risk after retransplantation and was adjusted for multiple covariates. Of 1,718 liver retransplantations during the study period, 464 (27%) were associated with a diagnosis of HCV infection. Based on Cox regression, retransplant recipients with HCV had a 30% higher covariate-adjusted mortality risk than those without HCV diagnosis (hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.10-1.54;

P

= 0.002). Other covariates associated with significant relative risk of death after retransplantation included older recipient age, presence in an intensive care unit (ICU), serum creatinine, and donor age. Additional regression analysis revealed that the increase in mortality risk associated with HCV was concentrated between 3 and 24 months postretransplantation, among patients age 18 to 39 at retransplant, and in patients retransplanted during the years 2000 to 2002. In conclusion, HCV liver recipients account for a considerable proportion of all retransplantations performed. Surprisingly, younger age predicted a higher mortality for recipients with HCV undergoing liver retransplantation. This may reflect a willingness to retransplant younger patients with an increased severity of illness or a more virulent HCV infection in this population. Although HCV was predictive of an increased risk of death, consideration of other characteristics of HCV patients, including donor and recipient age and need for preoperative ICU care may identify those at significantly higher risk. (Liver Transpl 2005;11:434–440.)
Hepatocyte expression of minichromosome maintenance protein-2 predicts fibrosis progression after transplantation for chronic hepatitis C virus: A pilot study
Authors: Marshall Aileen , Rushbrook Simon , Morris Lesley S. , Scott Ian S. , Vowler Sarah L. , Davies Susan E. , Coleman Nicholas , Alexander Graeme
Published: March 2005

Although graft infection with hepatitis C virus (HCV) occurs in virtually all patients transplanted for HCV-related liver disease, the outcome ranges from minimal disease to the rapid development of cirrhosis. Induction of hepatocyte cell cycle entry followed by inhibition of cell cycle progression has been proposed as a potential mechanism whereby HCV may cause hepatocyte dysfunction and may promote fibrogenesis. The aim of this study was to assess whether early hepatocyte cell cycle entry might predict subsequent fibrosis progression in patients with graft HCV infection after liver transplantation. Liver biopsies from 21 liver transplant recipients diagnostic of graft HCV infection but before development of significant fibrosis were studied. Patients were classed as nonprogressors, intermediate progressors, or rapid progressors according to the rate of fibrosis progression calculated from the most recent biopsy. Minichromosome maintenance protein 2 (Mcm-2), a highly sensitive and specific marker of cell cycle entry, and cyclin-dependent kinase inhibitor p21 were detected by immunohistochemistry. Hepatocyte Mcm-2 expression increased significantly according to rate of fibrosis. For nonprogressors, the median percentage of positive hepatocytes was 5.3% (range, 0.92%-11.2%) compared with 20.7% (4.6%-43.7%) in intermediate progressors and 23.7% (11.6%-55.2%) in rapid progressors (

P

= 0.002). By contrast, there was no evidence of a difference in hepatocyte p21 expression. Median values and ranges were 3.4% (range, 1.1%-30%), 13.3% (range, 1.4%-42.3%), and 11.8% (range, 7.6%-52.3%) for nonprogressors, intermediate progressors, and rapid progressors, respectively (

P

= 0.11). In conclusion, hepatocyte cell cycle entry may be important in the pathogenesis of posttransplant HCV hepatitis. Early assessment of hepatocyte Mcm-2 expression could help identify patients at high risk for progressive fibrosis before it occurs. (Liver Transpl 2005;11:427–433.)
Alcohol recidivism impairs long-term patient survival after orthotopic liver transplantation for alcoholic liver disease
Authors: Cuadrado Antonio , Fábrega Emilio , Casafont Fernando , Pons-Romero Fernando
Published: March 2005

The aim of this study was to evaluate the rate of alcohol recidivism after orthotopic liver transplantation (OLT) for alcoholic liver disease (ALD) and its influence on the allograft and patient survival, as well as the development of comorbidities and de novo cancers. The study was performed on 54 subjects previously analyzed and transplanted in our center for ALD, whose follow-up was prolonged to a mean of 99.2 (SD 31.7) months (range, 14–155). Medical records were reviewed, and data on alcohol consumption, therapeutic compliance, graft evolution, rejection, infections, comorbidities, rates of de novo malignancies and other clinical events, and survival were collected. Comparisons between groups were performed by the Fisher's exact test, and survival was assessed by the Kaplan-Meier method. Survival curves were compared using the Mantel-Cox statistic. The risk of death resulting from alcohol recidivism was analyzed with a Cox proportional hazards model. Fourteen patients who underwent transplantation for ALD (25.9%) returned to alcohol use between 5.0 and 86.9 months after OLT (median, 47.5). There was no significant association between the presence or absence of alcohol recidivism and the occurrence of graft rejection, infections, associated comorbidities after OLT, or compliance. The 5- and 10-year survival rates for patients with alcohol recidivism were 92.9% and 45.1%, respectively, compared with 92.4% and 85.5%, respectively, for patients without alcohol recidivism. These figures show significantly lower survival rates in recidivistic patients after 10 years (

P

< 0.01, Mantel-Cox). The fact that patients who resumed alcohol consumption have a worse 10-year survival rate might be attributed to a higher frequency of deaths, primarily from cancer and cardiovascular events. (Liver Transpl 2005;11:420–426.)
Myocardial osteopontin expression is associated with collagen fibrillogenesis in human dilated cardiomyopathy
Authors: Satoh Mamoru , Nakamura Motoyuki , Akatsu Tomonari , Shimoda Yudai , Segawa Ikuo , Hiramori Katsuhiko
Published: March 2005

Background

Osteopontin (OPN), an extracellular matrix (ECM) protein, plays an important role in myocardial remodeling by promoting collagen synthesis and accumulation in experimental animal models.

Aims

We hypothesized that OPN could be expressed in myocardial tissues and contribute to collagen accumulation and myocardial dysfunction in human dilated cardiomyopathy (DCM).

Methods and results

Endomyocardial biopsy tissues were obtained from 51 patients with DCM and 15 controls by right ventricular endomyocardial biopsy. OPN, collagen types I (Col I) and III (Col III) mRNA levels were measured by real‐time reverse transcriptase polymerase chain reaction (RT–PCR). The cellular source of OPN was analyzed using immunohistochemistry and in situ hybridization. Myocardial collagen volume fraction (CVF) was determined by digital planimetry. OPN, Col I and Col III mRNA levels were higher in DCM patients than in controls (P<0.01). OPN mRNA levels were positively correlated with Col I levels and CVF in DCM patients (OPN vs. Col I: r=0.60, P<0.01; OPN vs. CVF: r=0.52, P<0.001). Immunostaining of OPN was present in cardiomyocytes from DCM patients. In situ hybridization identified cardiomyocytes as the major source of OPN mRNA transcription in DCM patients. OPN and Col I mRNA levels were highly expressed in the DCM subgroup with large left ventricular (LV) end‐systolic diameter (LVESD≥54.5 mm) or low LV ejection fraction (LVEF<29.5%). There was a weak positive correlation between OPN mRNA levels and LV end‐systolic diameter (r=0.39, P<0.01). Levels of OPN mRNA were also negatively correlated with LV ejection fraction (r=−0.43, P<0.01).

Conclusions

These results suggest that OPN may play a pivotal role in the development of Col‐I‐induced cardiac fibrosis and dysfunction in human DCM.
Environmental NGOs and Institutional Dynamics in China
Authors: Yang Guobin
Published: March 2005

Environmental non-governmental organizations are becoming increasingly visible players in China's environmental politics. Adopting a field perspective, this article shows how the rise of environmental NGOs has taken place in interactions with four institutional fields. They not only respond to political conditions, but also to opportunities offered by the media, the internet and international NGOs. In this process, organizational entrepreneurs play a crucial role in mobilizing resources while other individuals participate in search of self-fulfilment or social experience. These arguments underscore the multi-institutional dynamics of civil society development without underestimating state-centred and market-centred explanations. In conclusion, the article discusses how environmental NGOs can serve as both sites and agents of democratic social change in China.
Interannual, solar cycle, and trend terms in middle atmospheric temperature time series from HALOE
Authors: Remsberg E. E. , Deaver L. E.
Published: March 2005

Temperature versus pressure or T(p) time series from the Halogen Occultation Experiment (HALOE) have been generated and analyzed for the period of 1991–2004 and for the mesosphere and upper stratosphere for latitude zones from 40N to 40S. Multiple linear regression (MLR) techniques were used for the analysis of the seasonal and the significant interannual and solar cycle (or decadal‐scale) terms. An 11‐yr solar cycle (SC) term of amplitude 0.5 to 1.7 K was found for the middle to upper mesosphere; its phase was determined by a Fourier fit to the de‐seasonalized residual. This SC term is largest and has a lag of several years for northern hemisphere middle latitudes of the middle mesosphere, perhaps due to the interfering effects of wintertime wave dissipation. The SC response from the MLR models is weaker but essentially in‐phase at low latitudes and in the southern hemisphere. An in‐phase SC response term is also significant near the tropical stratopause with an amplitude of about 0.4 to 0.6 K, which is somewhat less than predicted from models. Both sub‐biennial (688‐dy) and QBO (800‐dy) terms are resolved for the mid to upper stratosphere along with a decadal‐scale term that is presumed to have a 13.5‐yr period due to their predicted modulation. This decadal‐scale term is out‐of‐phase with the SC during 1991–2004. However, the true nature and source of this term is still uncertain, especially at 5 hPa. Significant linear cooling trends ranging from −0.3 K to −1.1 K per decade were found in the tropical upper stratosphere and subtropical mesosphere. Trends have not emerged so far for the tropical mesosphere, so it is concluded that the cooling rates that have been resolved for the subtropics are likely upper limits. As HALOE‐like measurements continue and their time series lengthen, it is anticipated that better accuracy can be achieved for these interannual, SC, and trend terms.
Columnar aerosol optical properties at AERONET sites in central eastern Asia and aerosol transport to the tropical mid‐Pacific
Authors: Eck T. F. , Holben B. N. , Dubovik O. , Smirnov A. , Goloub P. , Chen H. B. , Chatenet B. , Gomes L. , Zhang X.‐Y. , Tsay S.‐C. , Ji Q. , Giles D. , Slutsker I.
Published: March 2005

The column‐integrated optical properties of aerosol in the central eastern region of Asia and midtropical Pacific were investigated based on Sun/sky radiometer measurements made at Aerosol Robotic Network (AERONET) sites in these regions. Characterization of aerosol properties in the Asian region is important due to the rapid growth of both population and economic activity, with associated increases in fossil fuel combustion, and the possible regional and global climatic impacts of related aerosol emissions. Multiyear monitoring over the complete annual cycle at sites in China, Mongolia, South Korea, and Japan suggest spring and/or summer maximum in aerosol optical depth (τa) and a winter minimum; however, more monitoring is needed to establish accurate climatologies. The annual cycle of Angstrom wavelength exponent (α) showed a springtime minimum associated with dust storm activity; however, the monthly mean α440–870 was >0.8 even for the peak dust season at eastern Asian sites suggesting that fine mode pollution aerosol emitted from population centers in eastern Asia dominates the monthly aerosol optical influence even in spring as pollution aerosol mixes with coarse mode dust originating in western source regions. Aerosol optical depth peaks in spring in the tropical mid‐Pacific Ocean associated with seasonal shifts in atmospheric transport from Asia, and ∼35% of the springtime τa500 enhancement occurs at altitudes above 3.4 km. For predominately fine mode aerosol pollution cases, the average midvisible (∼550 nm) single scattering albedo (ω0) at two continental urban sites in China averaged ∼0.89, while it was significantly higher, ∼0.93, at two relatively rural coastal sites in South Korea and Japan. Differences in fine mode absorption between these regions may result from a combination of factors including aerosol aging during transport, relative humidity differences, sea salt at coastal sites, and fuel type and combustion differences in the two regions. For cases where τa was predominately coarse mode dust aerosol in the spring of 2001, the absorption was greater in eastern Asia compared to the source regions, with ω0 at Dunhuang, China (near to the major Taklamakan dust source), ∼0.04 higher than at Beijing at all wavelengths, and Anmyon, South Korea, showing an intermediate level of absorption. Possible reasons for differences in dust absorption magnitude include interactions between dust and fine mode pollution aerosol and also variability of dust optical properties from different source regions in China and Mongolia.
Variant histone H3.3 marks promoters of transcriptionally active genes during mammalian cell division
Authors: Chow Cheok‐Man , Georgiou Andrew , Szutorisz Henrietta , Maia e Silva Alexandra , Pombo Ana , Barahona Isabel , Dargelos Elise , Canzonetta Claudia , Dillon Niall
Published: March 2005

Variant histone H3.3 is incorporated into nucleosomes by a mechanism that does not require DNA replication and has also been implicated as a potential mediator of epigenetic memory of active transcriptional states. In this study, we have used chromatin immunoprecipitation analysis to show that H3.3 is found mainly at the promoters of transcriptionally active genes. We also show that H3.3 combines with H3 acetylation and K4 methylation to form a stable mark that persists during mitosis. Our results suggest that H3.3 is deposited principally through the action of chromatin‐remodelling complexes associated with transcriptional initiation, with deposition mediated by RNA polymerase II elongation having only a minor role.
Monitoring agonist‐promoted conformational changes of β‐arrestin in living cells by intramolecular BRET
Authors: Charest Pascale G , Terrillon Sonia , Bouvier Michel
Published: March 2005

Recruitment of β‐arrestin (β‐arr) to agonist‐stimulated G‐protein‐coupled receptors (GPCRs) has a crucial role in controlling signalling efficacy and selectivity. When translocated to the receptor, β‐arr is believed to undergo important conformational rearrangement necessary for its downstream actions. To probe these changes in living cells, we constructed an intramolecular bioluminescence resonance energy transfer (BRET)‐based biosensor, in which β‐arr is sandwiched between the Renilla luciferase (Luc) and the yellow fluorescent protein (YFP). We show that the intramolecular BRET between Luc and YFP was significantly increased following GPCR activation, suggesting a conformational rearrangement bringing the amino terminus and carboxyl terminus of β‐arr in closer proximity. Kinetic analysis showed that this conformational change follows the initial β‐arr/receptor engagement. In addition to providing new insights into the agonist‐induced conformational rearrangements of β‐arr in living cells, the double‐brilliance β‐arr offers a universal biosensor for GPCR activation, allowing the study of native receptors in large‐scale screening analysis.
Leading-order relativistic effects on nuclear magnetic resonance shielding tensors
Authors: Manninen Pekka , Ruud Kenneth , Lantto Perttu , Vaara Juha
Published: March 2005

We present perturbational ab initio calculations of the nuclear-spin-dependent relativistic corrections to the nuclear magnetic resonance shielding tensors that constitute, together with the other relativistic terms reported by us earlier, the full leading-order perturbational set of results for the one-electron relativistic contributions to this observable, based on the (Breit–)Pauli Hamiltonian. These contributions are considered for the H2X (X=O,S,Se,Te,Po) and HX (X=F,Cl,Br,I,At) molecules, as well as the noble gas (Ne, Ar, Kr, Xe, Rn) atoms. The corrections are evaluated using the relativistic and magnetic operators as perturbations on an equal footing, calculated using analytical linear and quadratic response theory applied on top of a nonrelativistic reference state provided by self-consistent field calculations. The H1 and heavy-atom nuclear magnetic shielding tensors are compared with four component, nearly basis-set-limit Dirac–Hartree–Fock calculations that include positronic excitations, as well as available literature data. Besides the easy interpretability of the different contributions in terms of familiar nonrelativistic concepts, the accuracy of the present perturbational scheme is striking for the isotropic part of the shielding tensor, for systems including elements up to Xe.
Charge-carrier properties in synthetic single-crystal diamond measured with the transient-current technique
Authors: Pernegger H. , Roe S. , Weilhammer P. , Eremin V. , Frais-Kölbl H. , Griesmayer E. , Kagan H. , Schnetzer S. , Stone R. , Trischuk W. , Twitchen D. , Whitehead A.
Published: March 2005

For optimal operation of chemical-vapor deposition (CVD) diamonds as charged particle detectors it is important to have a detailed understanding of the charge-carrier transport mechanism. This includes the determination of electron and hole drift velocities as a function of electric field, charge carrier lifetimes, as well as effective concentration of space charge in the detector bulk. We use the transient-current technique, which allows a direct determination of these parameters in a single measurement, to investigate the charge-carrier properties in a sample of single-crystal CVD diamond. The method is based on the injection of charge using an α source close to the surface and measuring the induced current in the detector electrodes as a function of time.
Adsorption and desorption of oxygen probed from ZnO nanowire films by photocurrent measurements
Authors: Li Q. H. , Gao T. , Wang Y. G. , Wang T. H.
Published: March 2005

Sensing mechanisms of ZnO nanowire films are investigated by performing transient photocurrent measurements. The current jumps upon ultraviolet or green laser illumination. The amplitude in the jump is strongly dependent on the ambient atmosphere. The decay rate is much more sensitive to the ambient atmosphere than the rise rate. The fast rise is due to rapid photogenerated carriers and the slow decay is controlled by slow surface process. Our experimental results indicate that the oxygen physisorption rate is slower than the chemisorption rate.
Glutamate receptor antagonist infusions into the basolateral and medial amygdala reveal differential contributions to olfactory vs. context fear conditioning and expression
Authors: Walker David L. , Paschall Gayla Y. , Davis Michael
Published: March 2005

The basolateral amygdala's involvement in fear acquisition and expression to visual and auditory stimuli is well known. The involvement of the basolateral and other amygdala areas in fear acquisition and expression to stimuli of other modalities is less certain. We evaluated the contribution of the basolateral and medial amygdala to olfactory and to context fear and fear conditioning by infusing into these areas the NMDA receptor antagonist AP5, the AMPA/kainate receptor antagonist NBQX, or vehicle prior to either odor-shock pairings or fear-potentiated startle testing. Pre-training AP5 infusions into the basolateral amygdala disrupted fear conditioning to the odor but not the context conditioned stimulus (CS). Pre-test NBQX infusions disrupted fear-potentiated startle to the odor but not context CS. Neither compound blocked fear conditioning when infused into the medial amygdala prior to training, but pre-test NBQX infusions did block fear-potentiated startle. The results confirm and extend recent findings suggesting a role for the basolateral amygdala in olfactory fear and fear conditioning, reveal an unexpected dissociation of the basolateral amygdala's involvement in discrete cue versus context fear and fear conditioning, and implicate for the first time the medial amygdala in fear-potentiated startle.
Victims of chronic dating violence: How women's vulnerabilities link to their decisions to stay*
Authors: Few April L. , Rosen Karen H.
Published: March 2005

Abstract: This article describes relational and situational vulnerabilities that emerged from interviews with 28 women (7 Black and 21 White) who were victims of chronic abuse suffered at the hands of male dating partners. Based on a qualitative content analysis, we explore how these vulnerabilities relate to women's decisions to stay in their abusive relationships and consider the implications of racial differences that emerged. Prevention and intervention strategies that help women see themselves as active choice makers are discussed.
Pharmacy Utilization and the Medicare Modernization Act
Authors: MAIO VITTORIO , PIZZI LAURA , ROUMM ADAM R. , CLARKE JANICE , GOLDFARB NEIL I. , NASH DAVID B. , CHESS DAVID
Published: March 2005

To control expenditures and use medications appropriately, the Medicare drug coverage program has established pharmacy utilization management (PUM) measures. This article assesses the effects of these strategies on the care of seniors. The literature suggests that although caps on drug benefits lower pharmaceutical costs, they may also increase the use of other health care services and hurt health outcomes. Our review raises concerns regarding the potential unintended effects of the Medicare drug program's PUM policies for beneficiaries. Therefore, the economic and clinical impact of PUM measures on seniors should be studied further to help policymakers design better drug benefit plans.
CONTINUOUS‐TIME MEAN‐VARIANCE PORTFOLIO SELECTION WITH BANKRUPTCY PROHIBITION
Authors: Bielecki Tomasz R. , Jin Hanqing , Pliska Stanley R. , Zhou Xun Yu
Published: March 2005

A continuous‐time mean‐variance portfolio selection problem is studied where all the market coefficients are random and the wealth process under any admissible trading strategy is not allowed to be below zero at any time. The trading strategy under consideration is defined in terms of the dollar amounts, rather than the proportions of wealth, allocated in individual stocks. The problem is completely solved using a decomposition approach. Specifically, a (constrained) variance minimizing problem is formulated and its feasibility is characterized. Then, after a system of equations for two Lagrange multipliers is solved, variance minimizing portfolios are derived as the replicating portfolios of some contingent claims, and the variance minimizing frontier is obtained. Finally, the efficient frontier is identified as an appropriate portion of the variance minimizing frontier after the monotonicity of the minimum variance on the expected terminal wealth over this portion is proved and all the efficient portfolios are found. In the special case where the market coefficients are deterministic, efficient portfolios are explicitly expressed as feedback of the current wealth, and the efficient frontier is represented by parameterized equations. Our results indicate that the efficient policy for a mean‐variance investor is simply to purchase a European put option that is chosen, according to his or her risk preferences, from a particular class of options.
Euglenoid morphospecies replacement along a hydraulic gradient of the Lower Paraná Basin (Argentina)
Authors: TELL GUILLERMO , O'FARRELL INÉS , LOMBARDO RUBEN JORGE
Published: March 2005

1. This study deals with the distribution of euglenoid morphospecies along the length of the Lower Paraná River floodplain. Six sites located in the Paraná River, Estevez stream and Montiel shallow lake were surveyed monthly from May 1995 to April 1996.

2. Eighty‐eight infrageneric taxa were registered though the total density percentage of euglenoids seldom exceeded 15% of total phytoplankton. The increasing species richness towards the lake is mostly the result of a high contribution of species of Trachelomonas and naked infrageneric taxa of Euglena, Lepocinclis and Phacus, while the distribution of Strombomonas species along the transect is fairly constant.

3. The richness of euglenoid morphospecies follows a pattern opposite to that found for the entire phytoplankton community. The distribution of euglenoids differs among the three habitats defined in this study: river, stream, shallow lake. These differences depend on the hydraulic condition of each habitat, as revealed by canonical correspondence analysis.

4. The degree of association with each type of aquatic habitat varied among the species and differed between water phases. Strombomonas fluviatilis was equally constant along the length of the ecotone, while S. girardiana and S. scabra were particularly associated with the Paraná River and P. longicauda, L. truncata, T. hispida and T. similis with the lake.

5. The flood pulse establishes a clear pattern both in species richness and abundance of euglenoids. The number of species recorded during high water was more than twice that recorded during low water.
Effect of bleaching agents on bonding to pulp chamber dentine
Authors: Timpawat S. , Nipattamanon C. , Kijsamanmith K. , Messer H. H.
Published: March 2005

Aim  To determine the effect of intracoronal bleaching agents on adhesion of bonding agents to pulp chamber dentine.

Methodology  Forty extracted human maxillary anterior teeth were randomly divided into four groups of 10 teeth each. Bleaching agents were sealed in pulp chambers for 7 days, as in clinical use. Group 1 (control): distilled water, group 2: 35% hydrogen peroxide, group 3: sodium perborate mixed with water, and group 4: sodium perborate mixed with 35% hydrogen peroxide. Teeth were stored in saline at 37 °C for 7 days. After the bleaching agent was removed, teeth were leached in water for a further 7 days prior to bonding. The crown was cut vertically from mesial to distal and the labial pulp chamber dentine was prepared for bonding with Clearfil SE‐Bond and filled with resin composite (Clearfil AP‐X). The bonded specimens were kept moist at 37 °C for 24 h. Microtensile bond strengths were determined using a universal testing machine. Additional teeth were prepared using the same bleaching procedures to investigate the scanning electron microscopic appearance of the dentine surface.

Results  Mean values (±SD) of microtensile bond strength for the experimental groups were: group 1: 5.29 ± 2.21 MPa, group 2: 5.99 ± 1.51 MPa, group 3: 9.17 ± 1.65 MPa and group 4: 3.99 ± 1.31 MPa. Dentine treated with sodium perborate in water (group 3) had significantly higher mean bond strength when compared with the other three groups (P < 0.05, Tukey's test). Mean bond strength was lowest when dentine was treated with sodium perborate plus hydrogen peroxide (group 4).

Conclusions  In terms of subsequent bond strength during restoration, sodium perborate mixed with distilled water appears to be the best intracoronal bleaching agent.
Transfusion‐transmitted malaria: current donor selection guidelines are not sufficient
Authors: Kitchen A. , Mijovic A. , Hewitt P.
Published: March 2005

A case of transfusion‐transmitted malaria was identified in a 50‐year‐old male patient with sickle cell disease. The donor was Ghanaian, but had migrated to the UK some years previously and had not left the UK for 8 years. The donor met all of the extant donor selection guidelines [1] and a donation was consequently collected. However, on subsequent investigation of the case, the donor was found to be parasitaemic and have high titre malarial antibodies. As a result of this case, changes to the United Kingdom donor selection guidelines have been proposed. These changes will prevent any such further transmissions.
A prospective trial on the safety of long‐term intensive plasmapheresis in donors
Authors: Bechtloff S. , Tran‐My B. , Haubelt H. , Stelzer G. , Anders C. , Hellstern P.
Published: March 2005

Background and Objectives  There are still concerns about the safety of long‐term intensive donor plasmapheresis, because the reasons that donors drop out of plasmapheresis programmes have not been determined in prospective studies.

Materials and Methods  Seventy‐two donors were switched from a moderate plasmapheresis programme to an intensive plasmapheresis programme and observed over a 3‐year period. In addition to measuring total serum protein (TSP), albumin, immunoglobulin G (IgG) and haemoglobin (Hb) levels, parameters of iron metabolism and blood coagulation, and biochemical cardiovascular risk markers, were determined at baseline and at every 15th donation. We also collected statements from donors who dropped out of the plasmapheresis programme about their reasons for withdrawal.

Results  Dropouts were predominantly related to socioeconomic (n = 34) or medical reasons not related to plasma donations (n = 8). Three donors had to drop out when their TSP levels fell below threshold for the third time within a 5‐week period. At baseline, donors had significantly lower TSP, albumin, IgG, Hb and ferritin levels than gender‐matched and age‐matched non‐donor controls. However, subsequent intensive plasmapheresis over 3 years did not impair the individuals’ ability to donate plasma. TSP, IgG, Hb, ferritin, transferrin, cardiovascular risk markers and parameters of blood coagulation did not change significantly during the observation period.

Conclusions  The reasons why donors cease to participate in intensive plasmapheresis programmes are predominantly not directly related to the plasma donation itself.
Relationship between dietary intake of cod liver oil in early pregnancy and birthweight
Authors: Olafsdottir Anna S. , Magnusardottir Anna R. , Thorgeirsdottir Holmfridur , Hauksson Arnar , Skuladottir Gudrun V. , Steingrimsdottir Laufey
Published: March 2005

Objective  To investigate the possible association between birth outcome and marine food and cod liver oil intake of healthy women in early (prior to 15 weeks of gestation) pregnancy.

Design  An observational study.

Setting  Free‐living conditions in a community with traditional fish and cod liver oil consumption.

Population  Four hundred and thirty‐five healthy pregnant Icelandic women without antenatal and intrapartum complications.

Methods  Dietary intake of the women was estimated with a semi‐quantitative food frequency questionnaire (FFQ) covering food intake together with lifestyle factors for the previous three months. Questionnaires were filled out at between 11 and 15 weeks and between 34 and 37 weeks of gestation. The estimated intake of marine food and cod liver oil was compared with birthweight by linear and logistic regression controlling for potential confounding.

Main outcome measures  Birthweight, cod liver oil intake, lifestyle factors (alcohol, smoking).

Results  Fourteen percent of the study population used liquid cod liver oil in early pregnancy. Regression analysis shows that these women gave birth to heavier babies (P < 0.001), even after adjusting for the length of gestation and other confounding.

Conclusions  Maternal intake of liquid cod liver oil early in pregnancy was associated with a higher birthweight. Higher birthweight has been associated with a lower risk of diseases later in life and maternal cod liver oil intake might be one of the means for achieving higher birthweight.
Sequential, Bayesian Geostatistics: A Principled Method for Large Data Sets
Authors: Cornford Dan , Csató Lehel , Opper Manfred
Published: March 2005

The principled statistical application of Gaussian random field models used in geostatistics has historically been limited to data sets of a small size. This limitation is imposed by the requirement to store and invert the covariance matrix of all the samples to obtain a predictive distribution at unsampled locations, or to use likelihood‐based covariance estimation. Various ad hoc approaches to solve this problem have been adopted, such as selecting a neighborhood region and/or a small number of observations to use in the kriging process, but these have no sound theoretical basis and it is unclear what information is being lost. In this article, we present a Bayesian method for estimating the posterior mean and covariance structures of a Gaussian random field using a sequential estimation algorithm. By imposing sparsity in a well‐defined framework, the algorithm retains a subset of “basis vectors” that best represent the “true” posterior Gaussian random field model in the relative entropy sense. This allows a principled treatment of Gaussian random field models on very large data sets. The method is particularly appropriate when the Gaussian random field model is regarded as a latent variable model, which may be nonlinearly related to the observations. We show the application of the sequential, sparse Bayesian estimation in Gaussian random field models and discuss its merits and drawbacks.