bluuebunny/crossref_metadata_2025_split huggingface dataset:
Granule matrix property and rapid “kiss-and-run” exocytosis contribute to the different kinetics of catecholamine release from carotid glomus and adrenal chromaffin cells at matched quantal size
Authors: Wang Nan , Lee Andy K. , Yan Lei , Simpson Michael R. , Tse Amy , Tse Frederick W. 
Published: May 2012

Catecholamine-containing small dense core granules (SDCGs, vesicular diameter of ∼100 nm) are prominent in carotid glomus (chemosensory) cells and some neurons, but the release kinetics from individual SDCGs has not been studied in detail. In this study, we compared the amperometric signals from glomus cells with those from adrenal chromaffin cells, which also secrete catecholamine but via large dense core granules (LDCGs, vesicular diameter of ∼200–250 nm). When exocytosis was triggered by whole-cell dialysis (which raised the concentration of intracellular Ca2+([Ca2+]i) to ∼0.5 µmol/L), the proportion of the type of signal that represents a flickering fusion pore was 9-fold higher for glomus cells. Yet, at the same range of quantal size (Q, the total amount of catecholamine that can be released from a granule), the kinetics of every phase of the amperometric spike signals from glomus cells was faster. Our data indicate that the last phenomenon involved at least 2 mechanisms: (i) the granule matrix of glomus cells can supply a higher concentration of free catecholamine during exocytosis; (ii) a modest elevation of [Ca2+]itriggers a form of rapid “kiss-and-run” exocytosis, which is very prevalent among glomus SDCGs and leads to incomplete release of their catecholamine content (and underestimation of their Q value).
The Informal Economy in South Africa: Debates, Issues and Policies
Authors: Valodia Imraan , Devey Richard 
Published: May 2012

The idea of dualism in the South African economy, characterised by a ‘first’ and ‘second’ economy, has come to dominate government thinking in recent years. Using the panel component of the Labour Force Survey (LFS), we explore linkages between the formal and informal economy. Our analysis suggests that there is a high level of interaction between formal and informal work at the lower end of the labour market. At the household level too, access to stable employment in the formal economy is associated with higher levels of earning in the informal economy. Our findings have implications for poverty analysis in South Africa. Policy which views poverty as being located outside the mainstream of the economy—in the so-called ‘second economy’—is misleading. JEL Classifications: O17, O55
Informality and Openness to Trade: Insights from Cross-sectional and Panel Analyses
Authors: Fiess Norbert , Fugazza Marco 
Published: May 2012

The relationship between trade liberalisation and informal activity has received little theoretical and empirical attention. The conventional view poses that trade liberalisation would cause a rise in the share of informal production and a rise in informal employment. This article uses three different datasets to assess econometrically the sign of these relationships. Empirical results suggest that while informal output increases with deeper openness to trade, informal employment falls. JEL Classification: F13, F16, O17, C23
IgG opsonization of bacteria promotes Th17 responses via synergy between TLRs and FcγRIIa in human dendritic cells
Authors: den Dunnen Jeroen , Vogelpoel Lisa T. C. , Wypych Tomasz , Muller Femke J. M. , de Boer Leonie , Kuijpers Taco W. , Zaat Sebastiaan A. J. , Kapsenberg Martien L. , de Jong Esther C. 
Published: May 2012

AbstractDendritic cells (DCs) are essential in inducing adaptive immune responses against bacteria by expressing cytokines that skew T-cell responses toward protective Th17 cells. Although it is widely recognized that induction of these cytokines by DCs involves activation of multiple receptors, it is still incompletely characterized which combination of receptors specifically skews Th17-cell responses. Here we have identified a novel role for FcγRIIa in promoting human Th17 cells. Activation of DCs by bacteria opsonized by serum IgG strongly promoted Th17 responses, which was FcγRIIa-dependent and coincided with enhanced production of selected cytokines by DCs, including Th17-promoting IL-1β and IL-23. Notably, FcγRIIa stimulation on DCs did not induce cytokine production when stimulated individually, but selectively amplified cytokine responses through synergy with TLR2, 4, or 5. Importantly, this synergy is mediated at 2 different levels. First, TLR-FcγRIIa costimulation strongly increased transcription of pro-IL-1β and IL-23p19. Second, FcγRIIa triggering induced activation of caspase-1, which cleaves pro-IL-1β into its bioactive form and thereby enhanced IL-1β secretion. Taken together, these data identified cross-talk between TLRs and FcγRIIa as a novel mechanism by which DCs promote protective effector Th17-cell responses against bacteria.
“Burden of osteoporotic fractures in primary health care in Catalonia (Spain): a population-based study”
Authors: Pagès-Castellà Aina , Carbonell-Abella Cristina , Avilés Francesc Fina , Alzamora Maite , Baena-Díez Jose Miguel , Laguna Daniel Martínez , Nogués Xavier , Díez-Pérez Adolfo , Prieto-Alhambra Daniel 
Published: May 2012

Abstract

Background
Knowledge on the epidemiology of non-hip fractures in Spain is limited and somewhat outdated. Using computerized primary care records from the SIDIAP database, we derived age and sex-specific fracture incidence rates for the region of Catalonia during the year 2009.

Methods
The SIDIAP database contains quality-checked clinical information from computerized medical records of a representative sample of >5,800,000 patients (80% of the population of Catalonia). We conducted a retrospective cohort study including all patients aged ≥50 years, and followed them from January 1 to December 31, 2009. Major osteoporotic fractures registered in SIDIAP were ascertained using ICD-10 codes and validated by comparing data to hospital admission and patient-reported fractures records. Incidence rates and 95% confidence intervals were calculated.

Results
In total, 2,011,430 subjects were studied (54.6% women). Overall fracture rates were 10.91/1,000 person-years (py) [95%CI 10.89–10.92]: 15.18/1,000 py [15.15–15.21] in women and 5.78/1,000 py [5.76–5.79] in men. The most common fracture among women was wrist/forearm (3.86/1,000 py [3.74–3.98]), while among men it was clinical spine (1.25/1,000 py [1.18–1.33]). All fracture rates increased with age, but varying patterns were observed: while most of the fractures (hip, proximal humerus, clinical spine and pelvis) increased continuously with age, wrist and multiple rib fractures peaked at age 75–80 and then reached a plateau.

Conclusions
Our study provides local estimates of age, sex and site-specific fracture burden in primary health care, which will be helpful for health-care planning and delivery. A proportion of fractures are not reported in primary care records, leading to underestimation of fracture incidence rates in these data.
Aboriginal Health Workers experience multilevel barriers to quitting smoking: a qualitative study
Authors: Dawson Anna P , Cargo Margaret , Stewart Harold , Chong Alwin , Daniel Mark 
Published: May 2012

AbstractIntroductionLong-term measures to reduce tobacco consumption in Australia have had differential effects in the population. The prevalence of smoking in Aboriginal peoples is currently more than double that of the non-Aboriginal population. Aboriginal Health Workers are responsible for providing primary health care to Aboriginal clients including smoking cessation programs. However, Aboriginal Health Workers are frequently smokers themselves, and their smoking undermines the smoking cessation services they deliver to Aboriginal clients. An understanding of the barriers to quitting smoking experienced by Aboriginal Health Workers is needed to design culturally relevant smoking cessation programs. Once smoking is reduced in Aboriginal Health Workers, they may then be able to support Aboriginal clients to quit smoking.MethodsWe undertook a fundamental qualitative description study underpinned by social ecological theory. The research was participatory, and academic researchers worked in partnership with personnel from the local Aboriginal health council. The barriers Aboriginal Health Workers experience in relation to quitting smoking were explored in 34 semi-structured interviews (with 23 Aboriginal Health Workers and 11 other health staff) and 3 focus groups (n = 17 participants) with key informants. Content analysis was performed on transcribed text and interview notes.ResultsAboriginal Health Workers spoke of burdensome stress and grief which made them unable to prioritise quitting smoking. They lacked knowledge about quitting and access to culturally relevant quitting resources. Interpersonal obstacles included a social pressure to smoke, social exclusion when quitting, and few role models. In many workplaces, smoking was part of organisational culture and there were challenges to implementation of Smokefree policy. Respondents identified inadequate funding of tobacco programs and a lack of Smokefree public spaces as policy level barriers. The normalisation of smoking in Aboriginal society was an overarching challenge to quitting.ConclusionsAboriginal Health Workers experience multilevel barriers to quitting smoking that include personal, social, cultural and environmental factors. Multidimensional smoking cessation programs are needed that reduce the stress and burden for Aboriginal Health Workers; provide access to culturally relevant quitting resources; and address the prevailing normalisation of smoking in the family, workplace and community.
Group I mGluR antagonist rescues the deficit of D1-induced LTP in a mouse model of fragile X syndrome
Authors: Xu Zhao-Hui , Yang Qi , Feng Bin , Liu Shui-bing , Zhang Nan , Xing Jiang-hao , Li Xiao-Qiang , Wu Yu-mei , Gao Guo-Dong , Zhao Ming-Gao 
Published: May 2012

Abstract

Background
Fragile X syndrome (FXS) is caused by the absence of the mRNA-binding protein Fragile X mental retardation protein (FMRP), encoded by the Fmr1 gene. Overactive signaling by group 1 metabotropic glutamate receptor (Grp1 mGluR) could contribute to slowed synaptic development and other symptoms of FXS. Our previous study has identified that facilitation of synaptic long-term potentiation (LTP) by D1 receptor is impaired in Fmr1 knockout (KO) mice. However, the contribution of Grp1 mGluR to the facilitation of synaptic plasticity by D1 receptor stimulation in the prefrontal cortex has been less extensively studied.

Results
Here we demonstrated that DL-AP3, a Grp1 mGluR antagonist, rescued LTP facilitation by D1 receptor agonist SKF81297 in Fmr1KO mice. Grp1 mGluR inhibition restored the GluR1-subtype AMPA receptors surface insertion by D1 activation in the cultured Fmr1KO neurons. Simultaneous treatment of Grp1 mGluR antagonist with D1 agonist recovered the D1 receptor signaling by reversing the subcellular redistribution of G protein-coupled receptor kinase 2 (GRK2) in the Fmr1KO neurons. Treatment of SKF81297 alone failed to increase the phosphorylation of NR2B-containing N-methyl D-aspartate receptors (NMDARs) at Tyr-1472 (p-NR2B-Tyr1472) in the cultures from KO mice. However, simultaneous treatment of DL-AP3 could rescue the level of p-NR2B-Tyr1472 by SKF81297 in the cultures from KO mice. Furthermore, behavioral tests indicated that simultaneous treatment of Grp1 mGluR antagonist with D1 agonist inhibited hyperactivity and improved the learning ability in the Fmr1KO mice.

Conclusion
The findings demonstrate that mGluR1 inhibition is a useful strategy to recover D1 receptor signaling in the Fmr1KO mice, and combination of Grp1 mGluR antagonist and D1 agonist is a potential drug therapy for the FXS.
Peripheral blood lymphocytes from low-grade squamous intraepithelial lesions patients recognize vaccine antigens in the presence of activated dendritic cells, and produced high levels of CD8 + IFNγ + T cells and low levels of IL-2 when induced to proliferate
Authors: Hernández-Montes Jorge , Rocha-Zavaleta Leticia , Monroy-García Alberto , Weiss-Steider Benny , Zaragoza-Ortega María del Carmen , Cruz-Talonia Fernando , Cruz Omar Cruz y , Bonifaz-Alfonso Laura , Chávez-Rueda Adriana Karina , Rojo-Aguilar Martha Patricia , Legorreta-Haquet María Victoria , Mora-García María de Lourdes 
Published: May 2012

Abstract

Background
Most infections with human papillomavirus (HPV) are resolved without clinical intervention, but a minority evolves into chronic lesions of distinct grades, including cervical-uterine cancer. It is known that in most cases the immune system mediates elimination of HPV infection. However, the mechanism of immune evasion leading to HPV persistence and development of early cervical lesions is not fully understood. The aim of the present work was to evaluate the potential of peripheral blood leukocytes (PBL) from low-grade squamous intraepithelial lesions (LSIL) patients to be activated ex-vivo by vaccine antigens, the participation of cytotoxic lymphocytes and regulatory T cells, and to determine the secretion of Th1 and Th2 cytokines mediated by stimulation of T cell receptors.

Results
We found that PBL from LSIL patients showed a significantly lower proliferation rate to vaccine antigens as compared to that of healthy donors, even though there was not a difference in the presence of antibodies to those antigens in sera from both groups. We did not find differences in either the frequency of CD4 + CD25 + FoxP3+ in PBL, or the levels of IL-4, IL-5 and IL-10 in plasma or conditioned media from PBL incubated with TcR agonists in vitro, between the two groups. However, we detected a lower production of IL-2 and a higher proportion of CD8 + IFNγ + cells in PBL from LSIL patients as compared with PBL from normal donors. We also observed that PBL from patients infected by HPV-16 and −18 were not able to proliferate in the presence of soluble HPV antigens added to the culture; however, a high level of proliferation was attained when these antigens were presented by activated dendritic cells.

Conclusions
Our results suggest that the immunodeficiency reported in LSIL patients could be due to the inability of specific cytotoxic T lymphocytes that for some unknown reason are present but unable to mount a response when challenged with their antigens, probably related to an in situ IL-2 production deficiency.
Elevated serum leptin levels in patients with acute myocardial infarction; correlation with coronary angiographic and echocardiographic findings
Authors: Khafaji Hadi AR Hadi , Bener Abdul Bari , Rizk Nasser M , Al Suwaidi Jassim 
Published: May 2012

Abstract

Background
To assess the relationship between serial serum leptin levels in patients with acute myocardial infarction (AMI) who received thrombolysis and the degree of coronary atherosclerosis, coronary reperfusion, echocardiographic findings, and clinical outcome. 51 consecutive patients presenting with AMI were studied. Clinical characteristics including age, sex, body mass index (BMI) and cardiovascular risk factors were recorded. Serial serum leptin levels at the time of admission and subsequently at 0, 6, 12, 24, 36, 60 hours afterwards were obtained. Coronary angiography was performed in 34 patients; the relation between serum leptin levels and evidence of coronary reperfusion as well as the extent of coronary atherosclerosis according to the coronary artery surgery study classification (CASS) were evaluated. Echocardiographic evaluation was performed in all patients. 36 matched patients were enrolled as control group who had serum leptin level 9.4 ± 6.5 ng/ml.

Results
The patients mean age was 50.5 ± 10.6 years. There were 47 males and 3 females. 37.1% were diabetics, 23.5% were hypertensive, 21.6% were dyslipidemic and 22.7% were obese (BMI ≥ 30). Leptin concentrations (ng/ml) increased and peaked at the 4th sample (36 hrs) after admission (mean ± SD) sample (1) =9.55 ± 7.4, sample (2) =12.9 ± 8.4, sample (3) =13.8 ± 10.4, sample (4) =18.9 ± 18.1, sample (5) =11.4 ± 6.5, sample (6) =10.8 ± 8.9 ng/ml. There was a significant correlation between serum leptin and BMI (r = 0.342; p = 0.03). Leptin levels correlated significantly to creatine kinase level on the second day (r = 0.43, p ≤ 0.01). Significant correlation of mean serum leptin with the ejection fraction (P < 0.05) was found. No difference in timing of peak serum leptin between patients who achieved coronary reperfusion vs. those who did not (p = 0.8). There was a trend for an increase in the mean serum leptin levels with increasing number of diseased vessels. There was no correlation between serum leptin levels and outcome neither during the hospitalization nor at 9 months follow up.

Conclusion
Serum leptin levels increase after myocardial infarction. Serum leptin level may be a predictor of the left ventricular ejection fraction and the degree of atherosclerosis but not of coronary reperfusion.
Erratum to: A whole genome association study of mother-to-child transmission of HIV in Malawi
Authors: Joubert Bonnie R , Lange Ethan M , Franceschini Nora , Mwapasa Victor , North Kari E , Meshnick Steven R ,   the NIAID Center for HIV/AIDS Vaccine Immunology
Published: May 2012

AbstractA correction to: Bonnie R Joubert, Ethan M Lange, Nora Franceschini, Victor Mwapasa, Kari E North, Steven R Meshnick andthe NIAID Center for HIV/AIDS Vaccine Immunology. A whole genome association study of mother-to-child transmission of HIV in Malawi. Genome Medicine 2010, 2:17.
High-resolution computed tomography findings of swine-origin influenza A (H1N1) virus (S-OIV) infection: comparison with scrub typhus
Authors: Jo Bang Sil , Lee In Jae , Im Hyoung June , Lee Kwanseop 
Published: May 2012

BackgroundSwine-origin influenza A (H1N1) virus (S-OIV) infection and scrub typhus, also known as tsutsugamushi disease can manifest as acute respiratory illnesses, particularly during the late fall or early winter, with similar radiographic findings, such as a predominance of ground-glass opacity (GGO).PurposeTo differentiate S-OIV infection from scrub typhus using high-resolution computed tomography (HRCT).Material and MethodsWe retrospectively reviewed the HRCT findings of 14 patients with S-OIV infection and 10 patients with scrub typhus. We assessed the location, cross-sectional distribution, and the presence of a peribronchovascular distribution of GGO and consolidations on HRCT. We also assessed the presence of interlobular septal thickening, bronchial wall thickening, pneumothorax, pneumomediastinum, pleural effusion, and mediastinal or axillary lymph node enlargement.ResultsScrub typhus was more common than S-OIV in elderly patients ( P < 0.001). The monthly incidences of S-OIV and scrub typhus infection reached a peak between October and November. About 86% of S-OIV patients and 80% of scrub typhus patients presented with GGO. About 67% of the GGO lesions in S-OIV had a peribronchovascular distribution, but this was absent in scrub typhus ( P = 0.005). Consolidation (93% vs. 10%, P < 0.001) and bronchial wall thickening (43% vs. 0%, P = 0.024) were more frequent in S-OIV infection than scrub typhus. Interlobular septal thickening (90% vs. 36%, P = 0.013) and axillary lymphadenopathy (90% vs. 0%, P < 0.001) were more common in scrub typhus than S-OIV infection.ConclusionThere was considerable overlap in HRCT findings between S-OIV infection and scrub typhus. However, S-OIV showed a distinctive peribronchovascular distribution of GGO lesions. Consolidation and bronchial wall thickening were seen more frequently in S-OIV infection, whereas interlobular septal thickening and axillary lymphadenopathy were more common in scrub typhus. Thus, CT could be helpful for differential diagnosis between S-OIV infection and scrub typhus.
Prevalence of extravertebral cement leakage after vertebroplasty: procedural documentation versus CT detection
Authors: Martin Douglas J , Rad Arash Ehteshami , Kallmes David F 
Published: May 2012

Background Reported incidence of extravertebral cement leakage after vertebroplasty varies widely across studies. Purpose To retrospectively compare the relative detection rates of extravertebral leakage noted under intra-procedural fluoroscopic surveillance, postprocedure plain radiographs, and postprocedure computed tomography (CT) in a cohort of patients undergoing vertebroplasty. Material and Methods With IRB approval, we retrospectively identified 181 patients with 277 levels treated with percutaneous vertebroplasty among a total of 1255 patients undergoing vertebroplasty between 1999 and 2010 who had subsequently undergone a CT examination that included the treated level(s). Categories of leakage were paravertebral, end plate, epidural, and prevertebral venous leakage. CT-detected leak rates were then compared to those noted on the vertebroplasty procedure reports and the archived fluoroscopic images for this same cohort using Pearson's χ2 test. Results One hundred and forty-nine (82%, 95% CI 76–87%) of 181 patients demonstrated evidence of some type of leakage on CT at one or more treated levels. Sixty-two (34%, 95% CI 28–42%) and seventy-seven (50%, 95% CI 43–57%) of 149 CT-detected leaks were reported in the procedural dictation or detected on plain radiography ( P = 0.01 and 0.006, respectively). The most common type of leakage noted on CT was end plate ( n = 81, 45%, 95% CI 38–52%), followed by paravertebral ( n = 64, 35%, 95% CI 29–43%), epidural ( n = 36, 20%, 95% CI 15–26%), and prevertebral venous ( n = 32, 18%, 95% CI 13–24%). Conclusion Cement leakage after vertebroplasty is common and is often not reported by operators in procedural dictations. CT detects substantially more leaks than plain radiography.
Fluctuations of Fitness Distributions and the Rate of Muller’s Ratchet
Authors: Neher Richard A , Shraiman Boris I 
Published: May 2012

AbstractThe accumulation of deleterious mutations is driven by rare fluctuations that lead to the loss of all mutation free individuals, a process known as Muller’s ratchet. Even though Muller’s ratchet is a paradigmatic process in population genetics, a quantitative understanding of its rate is still lacking. The difficulty lies in the nontrivial nature of fluctuations in the fitness distribution, which control the rate of extinction of the fittest genotype. We address this problem using the simple but classic model of mutation selection balance with deleterious mutations all having the same effect on fitness. We show analytically how fluctuations among the fittest individuals propagate to individuals of lower fitness and have dramatically amplified effects on the bulk of the population at a later time. If a reduction in the size of the fittest class reduces the mean fitness only after a delay, selection opposing this reduction is also delayed. This delayed restoring force speeds up Muller’s ratchet. We show how the delayed response can be accounted for using a path-integral formulation of the stochastic dynamics and provide an expression for the rate of the ratchet that is accurate across a broad range of parameters.
Simulation of space charge limited organic non volatile memory elements
Authors: Santoni Francesco , Gagliardi Alessio , Di Carlo Aldo 
Published: May 2012

ABSTRACTWe present a model for organic bistable devices (OBDs) embedded with metallic nanoparticles. In particular, two device architectures have been studied: a single layer device with metallic nanoparticles dispersed in a organic material matrix and a three layer device where two organic material regions are separated by a layer of heavy packed nanoparticles. The model describes the different behavior, the internal charge and potential distributions in the ON-OFF states. The OFF state is represented by charged nanoparticles forming a space charge layer which limits the current. The ON state occurs with neutral nanoparticles.