bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anaphylaxis and cardiovascular disease: therapeutic dilemmas
Authors: Lieberman P. , Simons F. E. R. 
Published: February 2015

SummaryCardiovascular disease (CVD) increases the risk of severe or fatal anaphylaxis, and some medications for CVD treatment can exacerbate anaphylaxis. The aim of this article is to review the effect of anaphylaxis on the heart, the potential impact of medications for CVD on anaphylaxis and anaphylaxis treatment, and the cardiovascular effects of epinephrine. The therapeutic dilemmas arising from these issues are also discussed and management strategies proposed. PubMed searches were performed for the years 1990–2014 inclusive, using terms such as angiotensin‐converting enzyme (ACE) inhibitors, adrenaline, allergic myocardial infarction, anaphylaxis, angiotensin‐receptor blockers (ARBs), beta‐adrenergic blockers, epinephrine, and Kounis syndrome. Literature analysis indicated that: cardiac mast cells are key constituents of atherosclerotic plaques; mast cell mediators play an important role in acute coronary syndrome (ACS); patients with CVD are at increased risk of developing severe or fatal anaphylaxis; and medications for CVD treatment, including beta‐adrenergic blockers and ACE inhibitors, potentially exacerbate anaphylaxis or make it more difficult to treat. Epinephrine increases myocardial contractility, decreases the duration of systole relative to diastole, and enhances coronary blood flow. Its transient adverse effects include pallor, tremor, anxiety, and palpitations. Serious adverse effects (including ventricular arrhythmias and hypertension) are rare, and are significantly more likely after intravenous injection than after intramuscular injection. Epinephrine is life‐saving in anaphylaxis; second‐line medications (including antihistamines and glucocorticoids) are not. In CVD patients (especially those with ACS), the decision to administer epinephrine for anaphylaxis can be difficult, and its benefits and potential harms need to be carefully considered. Concerns about potential adverse effects need to be weighed against concerns about possible death from untreated anaphylaxis, but there is no absolute contraindication to epinephrine injection in anaphylaxis.
The Effectiveness of a Customized Titanium Mesh for Ridge Preservation with Immediate Implantation in Dogs
Authors: Lim Hyun‐Chang , Kim Min‐Soo , Yang Cheryl , Lee Jung‐Seok , Hong Ji‐Youn , Choi Seong‐Ho , Jung Ui‐Won 
Published: February 2015

AbstractPurposeThe purpose of this study was to determine the effect of a newly designed titanium mesh (TM) for preserving the buccal bone around an immediately placed implant following tooth extraction in dogs.Materials and MethodsImmediate implant placements were performed bilaterally in the mesial socket of the fourth premolar in five dogs. In one site, the TM was affixed to the fixture using its own stabilization components (TM group), and the contralateral site was left untreated (control group). All surgical sites were intended to be submerged with primary flap closure. Histologic and histomorphometric analyses were performed 16 weeks postoperatively.ResultsAll implants were histologically osseointegrated, and buccal bone resorption was evident in both groups with the high rate of TM exposure (4/5). The most coronal level of bone‐implant contact and the bone crest were not statistically different between the TM and the control group. A dense connective tissue layer consistently predominated under the TM, where mineralized tissue was not observed, and the vascularity and cellularity were minimal.ConclusionsIt can be conjectured that preservation of buccal plate by using the TM in immediate implantation was not predictable due to vulnerability to wound dehiscence and substantial pseudoperiosteum formation beneath the TM.
Sinus floor elevation outcomes following perforation of the Schneiderian membrane. An experimental study in sheep
Authors: Favero Vittorio , Lang Niklaus P. , Canullo Luigi , Urbizo Velez Joaquin , Bengazi Franco , Botticelli Daniele 
Published: February 2015

AbstractObjectiveTo assess the influence of a collagen membrane covering a perforation of the sinus (Schneiderian) membrane on the outcome (bone fill) of a sinus floor elevation.Materials and MethodsEighteen Pelibuey sheep were used. The animals underwent sinus floor elevation on both sides of the upper jaw. A perforation of 5 × 4 mm in dimension of the sinus mucosa was performed on both sides and, at a randomly selected test site, a collagen membrane was placed to cover the perforation. A graft of biphasic calcium phosphate (60% HA/40% beta‐TCP) was subsequently placed bilaterally, and the access window was closed with a membrane made of polylactic acid and a citric acid ester acetyl. The sacrifices were performed after 2, 4, and 12 weeks of healing.ResultsAfter 2 weeks of healing, the augmented volume was filled with biomaterial surrounded by connective tissue and minimal new bone was detected. After 4 weeks of healing, new bone was found mainly in connection with the sinus bony walls with percentages of 18.0 ± 12.9% at the test and 12.3 ± 7.9% at the control sites. After 12 weeks of healing, similar amounts of newly formed bone were found compared to the previous healing period, namely 16.7 ± 8.0% and 13.7 ± 10.1% at the test and control sites, respectively, with the highest amount detected in the bottom of the sinus cavity. The newly formed bone was distributed more evenly within the sinus cavity also including the central areas. The differences between test and control sites did not reach statistical significance.ConclusionEven though there were trends for more bone formation when applying a collagen membrane on a sinus mucosal perforation of relatively small dimensions, this study failed to establish the absolute necessity of such a procedure to achieve bone fill in the sinus cavity.
Comparison of alemtuzumab vs. antithymocyte globulin induction therapy in primary non‐sensitized renal transplant patients treated with rapid steroid withdrawal
Authors: Saull Harrison E. , Enderby Cher Y. , Gonwa Thomas A. , Wadei Hani M. 
Published: February 2015

AbstractAlemtuzumab and rabbit antithymocyte globulin (rATG) are commonly used for induction therapy in renal transplantation. This retrospective, single‐center, cohort study evaluated cumulative incidence of one‐yr biopsy‐proven acute rejection (BPAR) among 200 consecutive primary non‐sensitized kidney transplant recipients who received either alemtuzumab (n = 100) or rATG (n = 100) induction followed by rapid steroid taper, tacrolimus, and mycophenolate mofetil. Protocol biopsies, plasma and urine BK virus PCR, serum creatinine and iothalamate glomerular filtration rate (iGFR), were obtained at 1, 4, and 12 months from transplantation. The one‐yr BPAR rates were similar between the alemtuzumab and rATG groups; however, rejection Banff IA and higher was more common in the alemtuzumab arm (18% vs. 5%, p = 0.047). After adjusting for confounding variables, alemtuzumab was still associated with Banff IA and higher rejection (adjusted OR: 3.7, CI: 1.2–10.5, p = 0.02). Despite similar rates of BK viremia, more patients in the alemtuzumab arm developed BK nephropathy (16% vs. 3%, p = 0.046). One‐year iGFR (53.4 ± 20.2 vs. 71.9 ± 27.2 mL/min/1.73 m2, p = 0.002) and three‐yr graft survival (89.5% vs. 95%, p = 0.05) were lower in the alemtuzumab group. In low immunological risk kidney transplant recipients on steroid‐free immunosuppression, alemtuzumab was associated with more severe rejection and BK nephropathy compared to rATG.
AIDS Activism in Pakistan: Diminishing Funds, Evasive State
Authors: Qureshi Ayaz 
Published: February 2015

ABSTRACTThis article draws on a year of ethnographic fieldwork in the HIV/AIDS sector of Pakistan at the moment of rolling back a World Bank‐financed programme. Classified by UN agencies as at ‘high risk’ of a generalized HIV epidemic, Pakistan has an epidemiology driven by injecting drug use, and a Penal Code and Islamist legislation which criminalize non‐therapeutic drug use and extra‐marital sex. In recent years, a sharp increase in the numbers of registered HIV‐positive people has necessitated a shift from HIV prevention among ‘high risk groups’ to the provision of care to those living with HIV/AIDS. The rolling back of external funding, which was further compounded by the effects of devolution on the Ministry of Health, created challenges for AIDS activism in Pakistan, as reflected in the everyday lives — and deaths — of the patient‐activists and their community‐based organizations. This article recounts the story of one such aspiring AIDS activist caught in multiple dilemmas emanating from these macro‐processes. This story throws light on the limitations of the complex agency of actors in development, and shows how the shifting loci of power from the state to non‐state entities in the global neoliberal order impacts the provision of vital services like HIV prevention and AIDS control.
Emerging Markets for Nature and Challenges for the Ecosystem Service Approach
Authors: Pröpper Michael 
Published: February 2015

ABSTRACTEcosystem services (ESS) are a burdened concept. They are supposed to function as a protective mechanism to make nature economically visible, while simultaneously contributing to economic development. At the core of the concept is the ideal of concisely valued and well‐accounted‐for goods traded in markets by rational and moral actors. This virtual idea is being challenged by real local processes of short‐term commodification and market‐based incentives for profit making in ‘messy’, unequal and illegitimate ESS markets. This article presents a local case‐study perspective focusing on the thatch grass ESS in the Kavango Regions of Namibia, where harvesters have become involved in an emerging capitalist value chain. It shows how, against the background of a post‐colonial political‐institutional setting that leaves plenty of leeway for exploitation, the real‐life conflation of market incentives and cash desires transforms local subsistence, causes a revaluation of ESS, and poses a real challenge to the virtual ESS conservation approach. Instead of viewing ESS as countable items involved in beneficial market interactions, we need to come to a more precise understanding of the consequences, local vulnerabilities and externalities of ESS marketizations.
Firing properties of Renshaw cells defined by Chrna2 are modulated by hyperpolarizing and small conductance ion currents Ih and ISK
Authors: Perry Sharn , Gezelius Henrik , Larhammar Martin , Hilscher Markus M. , Lamotte d'Incamps Boris , Leao Katarina E. , Kullander Klas 
Published: February 2015

AbstractRenshaw cells in the spinal cord ventral horn regulate motoneuron output through recurrent inhibition. Renshaw cells can be identified in vitro using anatomical and cellular criteria; however, their functional role in locomotion remains poorly defined because of the difficulty of functionally isolating Renshaw cells from surrounding motor circuits. Here we aimed to investigate whether the cholinergic nicotinic receptor alpha2 (Chrna2) can be used to identify Renshaw cells (RCsα2) in the mouse spinal cord. Immunohistochemistry and electrophysiological characterization of passive and active RCsα2 properties confirmed that neurons genetically marked by the Chrna2‐Cre mouse line together with a fluorescent reporter mouse line are Renshaw cells. Whole‐cell patch‐clamp recordings revealed that RCsα2 constitute an electrophysiologically stereotyped population with a resting membrane potential of −50.5 ± 0.4 mV and an input resistance of 233.1 ± 11 MΩ. We identified a ZD7288‐sensitive hyperpolarization‐activated cation current (Ih) in all RCsα2, contributing to membrane repolarization but not to the resting membrane potential in neonatal mice. Additionally, we found RCsα2 to express small calcium‐activated potassium currents (ISK) that, when blocked by apamin, resulted in a complete attenuation of the afterhyperpolarisation potential, increasing cellular firing frequency. We conclude that RCsα2 can be genetically targeted through their selective Chrna2 expression and that they display currents known to modulate rebound excitation and firing frequency. The genetic identification of Renshaw cells and their electrophysiological profile is required for genetic and pharmacological manipulation as well as computational simulations with the aim to understand their functional role.
Downregulation of natriuretic peptide clearance receptor mRNA in vascular smooth muscle cells by angiotensin II
Authors: Jiao Yuhang , Yang Qing 
Published: February 2015

AbstractAngiotensin II can downregulate atrial natriuretic peptide binding to rat vascular smooth muscle cells (VSMCs), but the mechanism is not known. Because protein kinase C (PKC) mimetic phorbol myristate acetate (PMA) can destabilize natriuretic peptide clearance receptor (NPR‐C) mRNA and angiotensin II activates several PKC isoforms in VSMCs, we hypothesized that angiotensin II treatment decreases NPR‐C mRNA stability and exerts this effect through PKC. This study demonstrated that angiotensin II induced time‐ and concentration‐dependent downregulation of NPR‐C, which was completely inhibited by an angiotensin II type I receptor blocker losartan. NPR‐C mRNA disappearance rate over 6 h was nearly doubled by exposure of VSMCs to 100 nm angiotensin II, compared with that observed after inhibition of RNA synthesis alone. However, this response to angiotensin II was undiminished by the PKC inhibitor chelerythrine, or by depletion of PKC by prior exposure of cells to PMA for 48 h. Inhibitors of tyrosine kinases, phospholipase C, or mitogen‐activated protein kinase kinase also failed to reverse the angiotensin II effect. We conclude that at least two distinct proximal signaling pathways, one involved and one independent of phorbol ester‐sensitive protein kinase C, lead to downregulation of NPR‐C gene expression by destabilizing its mRNA.
5‐HT3 receptors antagonists reduce serotonin‐induced scratching in mice
Authors: Ostadhadi Sattar , Kordjazy Nastaran , Haj‐Mirzaian Arya , Mansouri Parvin , Dehpour Ahmad Reza 
Published: February 2015

AbstractSerotonin (5‐hydroxytryptamine, 5‐HT) acts as a pruritogen in humans and animals, but the mechanisms of action through that serotonin induces itch response have not been extensively discovered. In our study, we attempted to investigate the role of 5‐HT3 receptors in scratching behavior due to intradermal serotonin injection. Intradermal injection of serotonin (14.1–235 nmol/site) into the nape of the neck of mice was performed to elicit itch. Scratching behavior was evaluated by measuring the number of bouts during 60 min after injection. We evaluated the effect of intraperitoneal pretreatment with ondansetron and tropisetron (0.1, 0.3, and 1 mg/kg) on itch induced by serotonin. Also, intradermal ondansetron and tropisetron at doses 50, 100, and 200 nmol/site were concurrently administrated with serotonin. Serotonin produced a significant enhancement in scratching at dose 141 nmol/site. Concurrent administration of ondansetron (50, 100, and 200 nmol/site) and tropisetron (100 and 200 nmol/site) with serotonin reduced scratching activity compared to the animals that only received serotonin. Also, pretreatment with intraperitoneal ondansetron and tropisetron (0.3 and 1 mg/kg) 30 min before serotonin attenuated the itch response. We showed that the scratching induced by intradermal serotonin is mediated by 5‐HT3 receptors subtype. It can be concluded that 5‐HT3 may play a role in mediating serotonin‐associated itch responses, and we introduce 5‐HT3 receptors as possible targets for antipruritic agents.
Kinetic mechanism of l–α–glycerophosphate oxidase from Mycoplasma pneumoniae
Authors: Maenpuen Somchart , Watthaisong Pratchaya , Supon Pacharee , Sucharitakul Jeerus , Parsonage Derek , Karplus P. Andrew , Claiborne Al , Chaiyen Pimchai 
Published: February 2015

l–α‐glycerophosphate oxidase is an FAD‐dependent enzyme that catalyzes the oxidation of l–α‐glycerophosphate (Glp) by molecular oxygen to generate dihydroxyacetone phosphate (DHAP) and hydrogen peroxide (H2O2). The catalytic properties of recombinant His6‐GlpO from Mycoplasma pneumoniae (His6‐MpGlpO) were investigated through transient and steady‐state kinetics and ligand binding studies. The results indicate that the reaction mechanism of His6‐MpGlpO follows a ping‐pong model. Double‐mixing mode stopped‐flow experiments show that, after flavin‐mediated substrate oxidation, DHAP leaves rapidly prior to the oxygen reaction. The values determined for the individual rate constants and kcat (4.2 s−1 at 4 °C), in addition to the finding that H2O2 binds to the oxidized enzyme, suggest that H2O2 release is the rate‐limiting step for the overall reaction. The results indicate that His6‐MpGlpO contains mixed populations of fast‐ and slow‐reacting species. It is predominantly the fast‐reacting species that participates in turnover. In contrast to other GlpO enzymes previously described, His6‐MpGlpO is able to catalyze the reverse reaction of reduced enzyme and DHAP. This result may be explained by the standard reduction potential value of His6‐MpGlpO (−167 ± 1 mV), which is lower than those of GlpO from other species. We found that d,l–glyceraldehyde 3–phosphate (GAP) may be used as a substrate in the His6‐MpGlpO reaction, although it exhibited an approximately 100‐fold lower kcat value in comparison with the reaction of Glp. These results also imply involvement of GlpO in glycolysis, as well as in lipid and glycerol metabolism. The kinetic models and distinctive properties of His6‐MpGlpO reported here should be useful for future drug development against Mycoplasma pneumoniae infection.
Lignin decomposition is sustained under fluctuating redox conditions in humid tropical forest soils
Authors: Hall Steven J. , Silver Whendee L. , Timokhin Vitaliy I. , Hammel Kenneth E. 
Published: February 2015

AbstractLignin mineralization represents a critical flux in the terrestrial carbon (C) cycle, yet little is known about mechanisms and environmental factors controlling lignin breakdown in mineral soils. Hypoxia is thought to suppress lignin decomposition, yet potential effects of oxygen (O2) variability in surface soils have not been explored. Here, we tested the impact of redox fluctuations on lignin breakdown in humid tropical forest soils during ten‐week laboratory incubations. We used synthetic lignins labeled with 13C in either of two positions (aromatic methoxyl or propyl side chain Cβ) to provide highly sensitive and specific measures of lignin mineralization seldom employed in soils. Four‐day redox fluctuations increased the percent contribution of methoxyl C to soil respiration relative to static aerobic conditions, and cumulative methoxyl‐C mineralization was statistically equivalent under static aerobic and fluctuating redox conditions despite lower soil respiration in the latter treatment. Contributions of the less labile lignin Cβ to soil respiration were equivalent in the static aerobic and fluctuating redox treatments during periods of O2 exposure, and tended to decline during periods of O2 limitation, resulting in lower cumulative Cβ mineralization in the fluctuating treatment relative to the static aerobic treatment. However, cumulative mineralization of both the Cβ‐ and methoxyl‐labeled lignins nearly doubled in the fluctuating treatment relative to the static aerobic treatment when total lignin mineralization was normalized to total O2 exposure. Oxygen fluctuations are thought to be suboptimal for canonical lignin‐degrading microorganisms. However, O2 fluctuations drove substantial Fe reduction and oxidation, and reactive oxygen species generated during abiotic Fe oxidation might explain the elevated contribution of lignin to C mineralization. Iron redox cycling provides a potential mechanism for lignin depletion in soil organic matter. Couplings between soil moisture, redox fluctuations, and lignin breakdown provide a potential link between climate variability and the biochemical composition of soil organic matter.
Antecedent moisture and temperature conditions modulate the response of ecosystem respiration to elevated CO2 and warming
Authors: Ryan Edmund M. , Ogle Kiona , Zelikova Tamara J. , LeCain Dan R. , Williams David G. , Morgan Jack A. , Pendall Elise 
Published: February 2015

AbstractTerrestrial plant and soil respiration, or ecosystem respiration (Reco), represents a major CO2 flux in the global carbon cycle. However, there is disagreement in how Reco will respond to future global changes, such as elevated atmosphere CO2 and warming. To address this, we synthesized six years (2007–2012) of Reco data from the Prairie Heating And CO2 Enrichment (PHACE) experiment. We applied a semi‐mechanistic temperature–response model to simultaneously evaluate the response of Reco to three treatment factors (elevated CO2, warming, and soil water manipulation) and their interactions with antecedent soil conditions [e.g., past soil water content (SWC) and temperature (SoilT)] and aboveground factors (e.g., vapor pressure deficit, photosynthetically active radiation, vegetation greenness). The model fits the observed Reco well (R2 = 0.77). We applied the model to estimate annual (March–October) Reco, which was stimulated under elevated CO2 in most years, likely due to the indirect effect of elevated CO2 on SWC. When aggregated from 2007 to 2012, total six‐year Reco was stimulated by elevated CO2 singly (24%) or in combination with warming (28%). Warming had little effect on annual Reco under ambient CO2, but stimulated it under elevated CO2 (32% across all years) when precipitation was high (e.g., 44% in 2009, a ‘wet’ year). Treatment‐level differences in Reco can be partly attributed to the effects of antecedent SoilT and vegetation greenness on the apparent temperature sensitivity of Reco and to the effects of antecedent and current SWC and vegetation activity (greenness modulated by VPD) on Reco base rates. Thus, this study indicates that the incorporation of both antecedent environmental conditions and aboveground vegetation activity are critical to predicting Reco at multiple timescales (subdaily to annual) and under a future climate of elevated CO2 and warming.