bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Asian Soybean Rust Caused by Phakopsora pachyrhizi on Kudzu in South Africa
Authors: Pretorius Z. A. , Visser B. , du Preez P. J. 
Published: September 2007

Asian soybean rust was first reported on soybean in South Africa (SA) in 2001 (3). The disease has occurred in all ensuing seasons, particularly in the humid, eastern production regions, causing significant losses in soybean fields not protected by fungicides. In April 2005, rust-infected Pueraria lobata (kudzu) was detected near Nelspruit, Mpumalanga, SA. At this location (25°20′41″S, 30°43′30″E), kudzu plants occurred abundantly on road sides, edges of pine plantations, and in natural vegetation. Most vines were infected, with abaxial surfaces of older leaves often showing 100% severity. Following inoculation with rust spores collected from kudzu, soybean line PI200492 (Rpp1) produced tan lesions typical of a susceptible reaction for Asian soybean rust. PI230970 (Rpp2), PI462312 (Rpp3), and PI459025 (Rpp4) showed red-brown lesions typical of a resistant reaction. Using Ppm1/Ppa2 and Ppm1/Ppm2 primer combinations, the amplification profiles of the internal transcribed spacer region (1) of rust DNA extracted from primary leaves of line PI200492 infected with spores collected from kudzu positively identified the pathogen as Phakopsora pachyrhizi. The Ppm1/Pme2 primer combination specific for P. meibomiae (1) did not yield an amplification product. The Qualiplate ELISA test kit (EnviroLogix Inc., Portland, ME) verified the identification of P. pachyrhizi on an original kudzu sample as well as the leaf material used for DNA analysis. A survey of kudzu at the Nelspruit site during July 2005 confirmed the presence of the pathogen during the offseason for soybean. At that time, incidence of kudzu rust remained high, but few leaves showed high severity. The susceptibility of kudzu to Asian soybean rust has been reported in controlled infection studies in SA (2). To our knowledge, this is the first report of P. pachyrhizi causing rust on a large, naturally occurring kudzu population in SA. References: (1) R. D. Frederick et al. Phytopathology 92:217, 2002. (2) A. Nunkumar. M.Sc. thesis. University of KwaZulu-Natal, South Africa, 2006. (3) Z. A. Pretorius et al. Plant Dis. 85:1288, 2001.
Growth, decay and bifurcation of shock amplitudes under the type-II flux law
Authors: Jordan P.M 
Published: September 2007

By replacing Fick's diffusion law with Green and Nagdhi's type-II flux law, a hyperbolic counterpart to the classical Fisher–KPP equation is obtained. In this article, an analytical study of this partial differential equation is presented with an emphasis on shock and related kinematic wave phenomena. First, an exact travelling wave solution (TWS) is derived and examined. Then, using singular surface theory, exact amplitude expressions for both shock and acceleration waves are obtained. In addition, the issue of shock stability is addressed and the limitations of the model are noted.
It is shown that discontinuity (i.e. shock) formation in the TWS occurs only when the propagation speed, which must exceed the characteristic speed, tends to the latter. It is also shown that the shock amplitude equation undergoes a transcritical bifurcation. Lastly, numerical simulations of acceleration waves in a simple model problem are presented.
Sublingual administration of furosemide: new application of an old drug
Authors: Haegeli Laurent , Brunner‐La Rocca Hans Peter , Wenk Markus , Pfisterer Matthias , Drewe Jürgen , Krähenbühl Stephan 
Published: September 2007

What is already known about this subject • Furosemide is an effective diuretic, but its absorption may be too slow to allow oral treatment in certain patients. What this study adds • In healthy volunteers, sublingual administration is associated with a higher Cmax, a higher bioavailability and a more accentuated initial natriuretic response than oral furosemide. Sublingual administration may offer advantages over oral administration of furosemide in certain clinical situations.BackgroundIn patients with decompensated heart failure, absorption of orally administered furosemide may be delayed, possibly leading to impaired pharmacodynamic effects. Sublingual administration may represent an alternative in such situations.MethodsIn a crossover study including 11 healthy men, 20 mg furosemide was administered intravenously, orally and sublingually on three different days. Pharmacokinetics and pharmacodynamics were assessed from repeated blood and urine samples.ResultsCompared with oral administration, sublingual administration was associated with 43% higher Cmax[difference 215 ng ml−1, 95% confidence interval (CI) 37, 392], a higher urinary recovery (8.9 vs. 7.3 mg, difference 1.6 mg, 95% CI 0.3, 2.9), an 28% higher AUC (difference 328 ng h−1 ml−1, 95% CI 24, 632) and a higher bioavailability of furosemide (59 vs. 47%, difference 12.0%, 95% CI −1.2, 25.2). Sodium excretion was higher after sublingual compared with oral administration (peak excretion rate 1.8 vs. 1.4 mmol min−1, P < 0.05), whereas urine volume did not differ significantly between the two application modes. In comparison, intravenous administration showed the expected more rapid and intense response.ConclusionSublingually administered furosemide tablets differ in certain kinetic and dynamic properties from identical tablets given orally. Sublingual administration of furosemide may offer therapeutic advantages in certain groups of patients.
The effect of dietary l‐carnitine supplementation on pulmonary hypertension syndrome mortality in broilers exposed to low temperatures
Authors: Tan X. , Hu S. H. , Wang X. L. 
Published: September 2007

SummaryOxidative stress is involved in the development of pulmonary hypertension syndrome (PHS) in broilers. l‐Carnitine has an antiperoxidative effect and supplemental l‐carnitine has been revealed to increase broiler heart weight. The present study was conducted to evaluate the effect of an addition of 100 mg/kg l‐carnitine to the basal diets on PHS mortality in cold‐exposed broilers. Two‐hundred and forty mixed‐sex broilers were equally assigned to three groups. The control group was reared in normal temperatures throughout the experiment. Starting on day 14 continuing until the end of the experiment, the other two groups were subjected to a step‐down temperature programme (by lowering the temperature 1–2 °C per day down to 12–14 °C) with or without l‐carnitine added to the basal diets. Cold exposure increased the right/total ventricle ratio (RV/TV) and plasma malondialdehyde (MDA), reduced superoxide dismutase (SOD) and led to pulmonary vascular remodelling in birds without feeding additional l‐carnitine. Supplemental l‐carnitine reduced plasma MDA, increased SOD, inhibited remodelling and postponed the occurrence of PHS for 1 week in cold‐exposed broilers; nevertheless, it did not significantly influence the cumulative PHS mortality (p > 0.05). On days 24 and 32, birds fed supplemental l‐carnitine had lower RV/TV and higher total ventricle/body weight (p < 0.05) but unchanged right ventricle/body weight ratios (p > 0.05) compared to their cold‐exposed counterparts, indicating an increase in left ventricle weight. However, from day 39 on, their RV/TV ratios were suddenly increased (p < 0.05). It was suggested that the l‐carnitine‐induced increase in left heart weight might partially account for the postponed occurrence of pulmonary hypertension in the early stage by elevating cardiac output, which might, in turn, lead to the resulting increase in pulmonary pressure. In view of its complex effects on cardiopulmonary haemodynamics, l‐carnitine supplementation may be impractical for reducing PHS.
A Comparative Clinical Study of Three Different Dosages of Intramuscular Midazolam–Medetomidine–Ketamine Immobilization in Cats
Authors: Ebner J. , Wehr U. , Busch R. , Erhardt W. , Henke J. 
Published: September 2007

SummaryA low dose of midazolam–medetomidine–ketamine (MMK) combination was evaluated in three increasing dosages. Each of the 18 cats was randomly allocated for several times to one of four groups. Five minutes after premedication with intramuscular (IM) 0.04 mg/kg atropine, group A (n = 43), B (n = 40) and C (n = 28) all were anaesthetized with 0.5 mg/kg midazolam, combined with 10, 20 or 30 μg/kg medetomidine, and 1.0, 2.0 or 3.0 mg/kg ketamine, respectively, IM in one syringe. Group D (n = 11) received the established combination of 50 μg/kg medetomidine and 10.0 mg/kg ketamine for comparison. Because this study was in cooperation with a project on dental prophylaxis, cats had to be immobilized for approximately 1 h. Therefore, anaesthesia was prolonged with propofol to effect, if necessary. Duration of MMK anaesthesia was between 30 ± 15, 45 ± 19 and 68 ± 28 min in groups A, B and C respectively. A significant decrease of respiratory rate was observed with increasing dosage, but venous carbon dioxide (pCO2) and pH values in combination with arterial oxygen saturation (SpO2) values were not alarming. The diastolic blood pressure particularly showed an increase. MMK combination A showed the best cardiovascular results, but it cannot be recommended due to disadvantages like a long induction time sometimes accompanied by excitations and the short duration of surgical immobilization. Dosage C in contrast had fewer side effects but less favourable cardiovascular results and a longer recovery period. However, either dosage B or C was suitable as a repeatable IM immobilization method for non‐invasive procedures in healthy cats.
Effects of Abdominal Surgery on Thiobarbituric acid Reactive Substances and Plasma Anti‐oxidative Capacity in Dairy Cows
Authors: Mudron P. , Herzog K. , Höltershinken M. , Rehage J. 
Published: September 2007

SummaryThe present investigation was undertaken to study the effects of surgical stress on thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) in dairy cows. Ten Holstein–Friesian dairy cows, mean age 5.26 years, admitted for treatment of left abomasal displacement (omentopexy), were used in our study. Blood samples were collected from the jugular vein prior to surgery, immediately and then 15, 30, 60, 90 min, and 2, 5, 10, and 24 h after reposition of abomasum. Surgical stress resulted in a significant increase in plasma cortisol concentrations (P < 0.001) with the highest mean levels 15 min after surgery (32.4 ± 18.1 μg/l) as well as in serum levels of glucose (P < 0.001) and non‐esterified fatty acids (P < 0.001). Similarly, surgery transiently enhanced the plasma levels of TBARS (P < 0.001). The highest TBARS plasma levels (0.91 ± 0.18 μmol/l) were recognized 60 min after reposition of abomasums. There were no significant differences in FRAP in dairy cows before and after reposition of abomasum. In conclusion, these data indicate that stress reaction caused by surgical correction of left displacement of abomasum can be associated with higher production of TBARS.
Extensive structural remodeling of the injured spinal cord revealed by phosphorylated MAP1B in sprouting axons and degenerating neurons
Authors: Soares Sylvia , Barnat Monia , Salim Claudio , Von Boxberg Ysander , Ravaille‐Veron Michèle , Nothias Fatiha 
Published: September 2007

AbstractSpinal cord injury (SCI) results in loss of sensory and motor function because injured axons do not regenerate and neurons that die are not replaced. Nevertheless, there is evidence for spontaneous reorganization of spared pathways (i.e. sprouting) that could be exploited to improve functional recovery. The extent of morphological remodeling after spinal cord injury is, however, not understood. We have previously shown that a phosphorylated form of microtubule‐associated protein‐1B, MAP1B‐P, is expressed by growing axons, but is detected in intact adult SC in fibers exhibiting a somatotopic distribution of myelinated sensory fibers. We now demonstrate that after adult SCI, MAP1B‐P is up‐regulated in other classes of axons. We used immunohistochemistry to show changing levels and distributions of MAP1B‐P after a right thoracic hemisection of adult rat spinal cord. MAP1B‐P labeling suggests rearrangements of the axonal circuitry that go well beyond previous descriptions. MAP1B‐P‐positive fibers are present in ectopic locations in gray matter in both dorsal and ventral horns and around the central canal. Double staining reveals that primary sensory and descending serotonergic and corticospinal axons are MAP1B‐P positive. In white matter, high MAP1B‐P expression is found on terminal enlargements near the injury, reflecting retraction of transected axons. MAP1B‐P also accumulates in pre‐apoptotic neuronal somata axotomized by the lesion, indicating association of MAP1B‐P not only with axon extension and retraction, but also with neuronal degeneration. Finally, we provide evidence that MAP1B phosphorylation is correlated with activation of JNK MAP‐kinase, providing a step towards unraveling the mechanisms of regulation of this plasticity‐related cytoskeletal protein.
Iron uptake by the ichthyotoxic Chattonella marina (Raphidophyceae): impact of superoxide generation1
Authors: Garg Shikha , Rose Andrew L. , Godrant Aurélie , Waite T. David 
Published: September 2007

Significant production of superoxide, a known reductant of both inorganic and organically complexed iron(III), occurs in natural systems by both biotic and abiotic pathways. We have investigated the generation of superoxide by Chattonella marina (Subrahman.) Y. Hara et Chihara, a phytoplankton taxon known to produce high levels of this reactive oxygen species, and examined the role of superoxide in the acquisition of iron by this organism. Additionally, a generalized model for iron acquisition by C. marina has been developed, which includes three pathways of iron acquisition from organically complexed iron(III): nondissociative reductive uptake, dissociative reductive uptake, and nonreductive dissociative uptake. The model is shown to be particularly useful in ascertaining the relative importance of these various iron‐uptake pathways as a function of solution parameters including concentration and iron‐binding strength of the organic ligand and superoxide concentration. Our results suggest that superoxide can participate in the C. marina iron‐uptake process when iron is complexed to weak ligands, such as citrate, but plays only a minor role when iron is bound to a strong ligand. It thus appears that facilitation of iron acquisition is not the sole purpose of superoxide production by these organisms.
Physician end‐of‐life decision‐making in newborns in a less developed health care setting: insight in considerations and implementation
Authors: Verhagen AAE , Spijkerman J , Muskiet FD , Sauer PJ 
Published: September 2007

AbstractBackground: A substantial proportion of the decisions to withhold or withdraw life‐prolonging treatment are based on the newborn's predicted poor quality of life. All previous studies on end‐of‐life decisions were done in countries with adequate support for disabled neonatal intensive care units (NICU) survivors. Data on quality‐of‐life considerations in countries with developing health care are not available yet.Aim: The aim of the study was to examine the considerations of physicians taking end‐of‐life decisions in sick newborns and how those decisions are carried out in practice in a less developed health care setting.Method: Thirty‐two deaths over 18 months in a neonatal unit were retrospectively analyzed.Results: Twenty‐four deaths (75%) were attributable to withholding or withdrawing of treatment. In 7 of these cases (29%), the decisions were based on quality‐of‐life considerations, mostly predicted suffering and expected hospital dependency. For the majority of paediatricians, end‐of‐life decision making was not influenced by legal or economic considerations or by considerations regarding availability of supportive care after discharge.Conclusion: Our study suggests that physician end‐of‐life decision making in this unit in a less developed health care setting is found to be similar to that in developed health care settings and is independent of availability of supportive care after discharge for infants with disabilities.
Promoting adolescent health
Authors: Kelly Kristina Berg 
Published: September 2007

AbstractThe aim is to discuss why paediatricians should be involved in adolescent health care and provide youth‐friendly‐health‐services. Global epidemiological data on morbidity and mortality demonstrate that much of ill health in the short and long run are connected to adolescent behaviour and in theory available for prevention. Young people seemingly lose their heads and do not consider dangers. Recent research on brain development provides us with an understanding how this may have a biological base. Also psychology has long taught us how adolescents use experimental behaviours as means to satisfy developmental needs and explore identity. Prevention and health promotion are areas of research where much more needs to be done. There is also a lack of venues for publishing even excellent studies in this field.
A Substituted Tetrahydro-Tetrazolo-Pyrimidine Is a Specific and Novel Inhibitor of Hepatitis B Virus Surface Antigen Secretion
Authors: Dougherty Anne Marie , Guo Haitao , Westby Gael , Liu Yuanjie , Simsek Ender , Guo Ju-Tao , Mehta Anand , Norton Pamela , Gu Baohua , Block Timothy , Cuconati Andrea 
Published: September 2007

ABSTRACTThe high levels of hepatitis B virus (HBV) surface antigen (HBsAg)-bearing subviral particles in the serum of chronically infected individuals are thought to play a role in suppressing the HBV-specific immune response. Current therapeutics are not directed at reducing this viral antigenemia; thus, our group has focused on identifying inhibitors of HBsAg secretion. By using the HBV-expressing cell line HepG2.2.15, high-throughput screening of an 80,288-compound synthetic small-molecule library identified HBF-0259, an aromatically substituted tetrahydro-tetrazolo-(1, 5-a)-pyrimidine. Following resynthesis, HBF-0259 had a 50% effective concentration of approximately 1.5 μM in a secondary, HBV-expressing cell line, with a concentration that exhibited 50% cytotoxicity of >50 μM. The equilibrium concentration of HBF-0259 in aqueous solution at physiological pH was 15 to 16 μM; the selective index was thus >9. As intended by our screening paradigm, HBF-0259 is a selective, potent inhibitor of secretion of both subviral and DNA-containing viral particles, while the secretion of α-1-acid glycoprotein and α-1-antitrypsin was unaffected. The HBV e antigen, which is not a constituent of HBV particles, was also unaffected, suggesting that the secretion of particles bearing HBV structural glycoproteins is targeted directly. Inhibitory activity was also confirmed by transfection of HBsAg, indicating that the action of the compound is independent of those of other viral proteins. HBF-0259 had no effect on HBV DNA synthesis, demonstrating that inhibition is independent of viral genomic replication. Finally, HBF-0259 had little or no effect on the cell-to-cell spread of two unrelated viruses, suggesting that it is a specific inhibitor of secretion of HBsAg. Possible mechanisms of action and the implications for its development are discussed.
Ribosome Protection Prevents Azithromycin-Mediated Quorum-Sensing Modulation and Stationary-Phase Killing of
Pseudomonas aeruginosa
Authors: Köhler Thilo , Dumas Jean-Luc , Van Delden Christian 
Published: September 2007

ABSTRACT

In
Pseudomonas aeruginosa
, azithromycin has been shown to reduce virulence factor production, to retard biofilm formation, and to exhibit bactericidal effects on stationary-phase cells. In this study we analyzed whether these azithromycin-mediated effects require interaction with the ribosome. We blocked the access of azithromycin to the ribosome in
P. aeruginosa
PAO1 by expressing the 23S rRNA methylase ErmBP from
Clostridium perfringens
. Ribosome protection prevented the azithromycin-mediated reduction of elastase and rhamnolipid production, as well as the inhibition of swarming motility. Ribosome protection also prevented the killing of stationary-phase cells, suggesting that the cell-killing effect of azithromycin does not result solely from membrane destabilization. We further show that rhamnolipids are involved in cell killing, probably by increasing the uptake of the hydrophobic azithromycin molecule. These results have important implications for the treatment with azithromycin of patients chronically colonized by
P. aeruginosa
and might explain the variability in the efficacy of azithromycin treatments.
Role of Neutrophils in Preventing and Resolving Acute Fungal Sinusitis
Authors: Rodriguez Tobias E. , Falkowski Nicole R. , Harkema Jack R. , Huffnagle Gary B. 
Published: September 2007

ABSTRACTAcute fungal sinusitis (AFS) is a devastating disease of the paranasal sinuses afflicting immunocompromised individuals. Knowledge about this disease is limited to clinical observations because there are no animal models in which to study the pathogenesis of the infection. Our goal was to develop a murine model of AFS and examine the role of neutrophils in host defense within the nasal cavity. Female C57BL/6 mice were depleted of neutrophils using anti-Gr-1 monoclonal antibody from day −1 to day 5 postinfection to initiate a transient neutropenia within the mice. At day 0,Aspergillus fumigatusconidia were administered intranasally. The untreatedAspergillus-exposed group had significant neutrophil recruitment by day 3, but by day 7 the leukocyte numbers had returned to unexposed levels. There was not a significant influx of mononuclear cells at either time point. In contrast, beginning at day 3 postinfection and continuing through day 7, anti-Gr-1-treated mice had increased cellular recruitment consisting of banded neutrophils at day 3 and mature neutrophils at day 7. Hyphal masses developed only in the anti-Gr-1-treated mice (25 to 36%) but only during the period of treatment. When the treatment was discontinued, hyphal masses could no longer be detected in the nasal cavities of these mice. In contrast, cyclophosphamide treatment did not induce neutropenia, and the nasal cavity remained free of hyphal masses. These studies demonstrate the feasibility of using this model to study AFS and implicate neutrophils in protection of the sinuses against acuteAspergillusinfection and in clearance of established hyphal masses.