bluuebunny/crossref_metadata_2025_split huggingface dataset:
Healthcare costs of Staphylococcus aureus and Clostridium difficile infections in Veterans: role of vitamin D deficiency
Authors: YOUSSEF D. , BAILEY B. , EL ABBASSI A. , COPELAND R. , ADEBONOJO L. , MANNING T. , PEIRIS A. N. 
Published: January 2010

SUMMARYClostridium difficile and staphylococcal infections are associated with increased morbidity, mortality and healthcare costs. Vitamin D deficiency may also contribute to increased healthcare costs. There is increasing evidence that vitamin D may have an antimicrobial role. We examined the relationship of serum 25(OH)D levels to staphylococcal and C. difficile infections to determine if vitamin D deficiency was associated with adverse outcomes. In the outpatient setting, vitamin D deficiency in patients with C. difficile and staphylococcal infections were associated with significantly increased total outpatients costs and fee-based consultation. Laboratory expenses had a trend towards higher costs in the vitamin D-deficient group but did not reach statistical significance. The differences were most clearly seen in the in-patient group with enhanced laboratory, pharmacy and radiology costs. These differences resulted in vitamin D-deficient patients with C. difficile or staphylococcal infections having costs more than five times higher than the non-deficient patients. The total length of hospital stay was four times greater in the vitamin D-deficient group. In addition, the total number of hospitalizations was also significantly greater in the vitamin D-deficient group. Surgery costs demonstrated a tendency to be higher in the vitamin D-deficient group but failed to reach statistical significance. Vitamin D deficiency is intimately linked to adverse health outcomes and costs in Veterans with staphylococcal and C. difficile infections in North East Tennessee. We recommend that vitamin D status be checked in patients with these infections and appropriate therapy be instituted to restore vitamin D level to normal in an expeditious manner.
Mechanistic details of a protein–protein association pathway revealed by paramagnetic relaxation enhancement titration measurements
Authors: Fawzi Nicolas L. , Doucleff Michaeleen , Suh Jeong-Yong , Clore G. Marius 
Published: January 2010

Protein–protein association generally proceeds via the intermediary of a transient, lowly populated, encounter complex ensemble. The mechanism whereby the interacting molecules in this ensemble locate their final stereospecific structure is poorly understood. Further, a fundamental question is whether the encounter complex ensemble is an effectively homogeneous population of nonspecific complexes or whether it comprises a set of distinct structural and thermodynamic states. Here we use intermolecular paramagnetic relaxation enhancement (PRE), a technique that is exquisitely sensitive to lowly populated states in the fast exchange regime, to characterize the mechanistic details of the transient encounter complex interactions between the N-terminal domain of Enzyme I (EIN) and the histidine-containing phosphocarrier protein (HPr), two major bacterial signaling proteins. Experiments were conducted at an ionic strength of 150 mM NaCl to eliminate any spurious nonspecific associations not relevant under physiological conditions. By monitoring the dependence of the intermolecular transverse PRE (Γ
2
) rates measured on
15
N-labeled EIN on the concentration of paramagnetically labeled HPr, two distinct types of encounter complex configurations along the association pathway are identified and dissected. The first class, which is in equilibrium with and sterically occluded by the specific complex, probably involves rigid body rotations and small translations near or at the active site. In contrast, the second class of encounter complex configurations can coexist with the specific complex to form a ternary complex ensemble, which may help EIN compete with other HPr binding partners in vivo by increasing the effective local concentration of HPr even when the active site of EIN is occupied.
Observations of aminium salts in atmospheric nanoparticles and possible climatic implications
Authors: Smith James N. , Barsanti Kelley C. , Friedli Hans R. , Ehn Mikael , Kulmala Markku , Collins Donald R. , Scheckman Jacob H. , Williams Brent J. , McMurry Peter H. 
Published: January 2010

We present laboratory studies and field observations that explore the role of aminium salt formation in atmospheric nanoparticle growth. These measurements were performed using the Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) and Ultrafine Hygroscopicity Tandem Differential Mobility Analyzers. Laboratory measurements of alkylammonium—carboxylate salt nanoparticles show that these particles exhibit lower volatilities and only slightly lower hygroscopicities than ammonium sulfate nanoparticles. TDCIMS measurements of these aminium salts showed that the protonated amines underwent minimal decomposition during analysis, with detection sensitivities comparable to those of organic and inorganic deprotonated acids. TDCIMS observations made of a new particle formation event in an urban site in Tecamac, Mexico, clearly indicate the presence of protonated amines in 8–10 nm diameter particles accounting for about 47% of detected positive ions; 13 nm particles were hygroscopic with an average 90% RH growth factor of 1.42. Observations of a new particle formation event in a remote forested site in Hyytiälä, Finland, show the presence of aminium ions with deprotonated organic acids; 23% of the detected positive ions during this event are attributed to aminium salts while 10 nm particles had an average 90% RH growth factor of 1.27. Similar TDCIMS observations during events in Atlanta and in the vicinity of Boulder, Colorado, show that aminium salts accounted for 10–35% of detected positive ions. We conclude that aminium salts contribute significantly to nanoparticle growth and must be accounted for in models to accurately predict the impact of new particle formation on climate.
Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect
Authors: Swann Abigail L. , Fung Inez Y. , Levis Samuel , Bonan Gordon B. , Doney Scott C. 
Published: January 2010

Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice.
Optimizing Empirical Antimicrobial Therapy for Infection due to Gram-Negative Pathogens in the Intensive Care Unit: Utility of a Combination Antibiogram
Authors: Christoff Jennifer , Tolentino Jocelyn , Mawdsley Emily , Matushek Scott , Pitrak David , Weber Stephen G. 
Published: January 2010

Objective.To determine whether the use of dual antimicrobial therapy based on the results of a combination antibiotic susceptibility report (antibiogram) increases the likelihood of selecting adequate empirical coverage in critically ill patients with infection due to potentially resistant gram-negative pathogens.Design.Retrospective data analysis.Setting.Urban academic medical center.Methods.An analysis of culture results and susceptibility data from intensive care unit patients determined by the clinical microbiology laboratory was performed. The proportion of 5 common gram-negative pathogens susceptible to monotherapy with 1 of 3 antipseudomonal antibiotics (piperacillin-tazobactam, ceftazidime, or imipenem) was compared with the proportion susceptible to each of these 3 “backbone” agents plus 1 of 4 additional antimicrobial agents used in combination.Results.More than 5,000 clinical isolates were examined. When all isolates recovered during the entire study period were included, the addition of any of the second antibiotics studied to each of the 3 backbone agents significantly increased the likelihood of covering the causative pathogen (P<.01 for each). The benefit of combination therapy was variable when results for each of the 5 organisms were examined individually. When temporal trends in susceptibility were examined, the decrease in the proportion of organisms susceptible to monotherapy was statistically significant for both imipenem and ceftazidime (P<.01).Conclusions.Reporting antibiotic susceptibility data in the form of a combination antibiogram may be useful to clinicians who are considering empirical antimicrobial therapy in the intensive care unit.
Comment on “Towards a precautionary approach to managing Canada's commercial harp seal hunt” by Leaper et al.
Authors: Hammill Michael O. , Stenson Garry B. 
Published: January 2010

Abstract
Hammill, M. O., and Stenson, G. B. 2010. Comment on “Towards a precautionary approach to managing Canada's commercial harp seal hunt” by Leaper et al. – ICES Journal of Marine Science, 67: 321–322. The Objective-Based Fisheries Management used by Canada to manage the Northwest Atlantic seal hunt conforms to United Nations and Canadian Government precautionary approach frameworks in its structure and industry involvement. Managers and industry use clearly identified thresholds and harvest control rules to adjust quotas to respect the management framework. Although simulation testing is needed to evaluate management model performance under additional sources of uncertainty, this approach has successfully maintained the harp seal population at or near the highest level ever seen, during a period of intensive hunting.
First Report of Pilidium concavum on Paeonia suffruticosa in China
Authors: Duan Y. B. , Kang Y. B. , Yu Z. Z. 
Published: January 2010

Paeonia suffruticosa Andrews, a deciduous perennial shrub, is known for its beautiful and charming flowers. It is regarded as the flower symbol of China and cultivated throughout the country. Since 2006, large, brown necrotic spots have been observed on numerous P. suffruticosa plants in gardens in Luoyang, China. Spots appeared each year and were observed on more than 50% of the plants, sometimes affecting more than half of the leaf. Initial symptoms appeared as small, round, water-soaked lesions in the middle or on the margin of leaves. These areas enlarged up to 1 to 3 cm in diameter and were circular or irregular, brown to dark brown, and pale brown on the margins. In a humid atmosphere, black, sessile, discoid conidiomata developed on the spots and exuded a pink spore mass that turned brown with age. Conidiophores were hyaline, unicellular, cylindrical, and fusiform and 5.0 to 8.0 μm long and 1.4 to 2.0 μm wide. Pure cultures were obtained by plating the spores on potato dextrose agar (PDA) medium. In culture, the fungus produced a gray-to-brown colony with whitish aerial mycelium. The morphology and size of conidia were comparable with previous descriptions of Pilidium concavum (Desm.) Höhn. (1). The ITS1-5.8S-ITS2 region of the isolate was amplified by PCR with primers ITS1 and ITS4 and sequenced. The 472-nt sequence was 100% identical to that of the Pilidium concavum specimen voucher BPI 1107275 (GenBank Accession No. AY487094). To validate Koch's postulates, pathogenicity was tested by inoculating 10 leaves of P. suffruticosa with mycelia plugs from a colony growing on PDA; leaves inoculated with the plugs of PDA medium only served as the control. Leaves were covered with plastic for 24 h to maintain high relative humidity. After 7 days, 100% of the mycelium-inoculated leaves showed symptoms identical to those observed on P. suffruticosa leaves affected in the field, whereas all leaves inoculated with PDA medium only remained free of symptoms. Reisolation of the fungus from leaf lesions confirmed that the causal agent was Pilidium concavum. Thus, we concluded that Pilidium concavum is the causal agent of leaf spots of P. suffruticosa. This disease has been reported to be frequently occurring on P. suffruticosa stems imported from Japan (1), but to our knowledge, this is the first report of Pilidium concavum on P. suffruticosa in China. References: (1) M. E. Palm. Mycologia 83:787, 1991.
First Report of Tomato leaf curl Palampur virus on Bitter Gourd in Pakistan
Authors: Ali I. , Malik A. H. , Mansoor S. 
Published: January 2010

Bitter gourd (Momordica charantia L.) is widely grown and consumed as a vegetable in Pakistan and other countries in the region. In 2007, a severe disease appeared on bitter gourd that reduced yield significantly. Symptoms of the disease included chlorosis, leaf crumpling, vein thickening, and stunting of plants that were suggestive of a virus infection. Symptomatic leaf samples were collected from fields in the vicinity of Faisalabad, Pakistan (Thikriwala, 12 km from Faisalabad, 31°22′0″N, 72°53′0″E). Seven infected samples were tested for the presence of Zucchini yellow mosaic virus (ZYMV), Cucumber mosaic virus, Papaya ringspot virus, Melon necrotic spot virus, and Squash mosaic virus by double-antibody sandwich-ELISA according to the manufacturer's instructions (Bio-Rad, Hercules, CA). All samples of bitter gourd were found to be negative for all five RNA viruses, whereas melon samples collected from the same area (Thikriwala) were infected by ZYMV as reported earlier (3). Samples were also screened for begomoviruses by molecular tests. Total DNA was extracted with the cetyltrimethylammoniumbromide method (4). All seven symptomatic samples were positive for a begomovirus when DNA A of Tomato leaf curl New Delhi virus (ToLCNDV) was used as a general probe by Southern hybridization. A probe of the movement protein (MP) gene of ToLCNDV was also positive by Southern hybridization, suggesting the infection of a bipartite begomovirus. The presence of a begomovirus was confirmed by PCR with universal primers designed for amplification of begomoviruses (BegomoRe F 5′ACGCGT GCCGTGCTGCTGCCCCCATTGTCC3′ and BegomoRe R 5′ACGCGT ATGGGCTGYCGAAGTTSAGACG3′). A fragment of the expected length (approximately 2.8 kb) was cloned in a T/A cloning vector (ptz57R/t; Fermentas, Burlington, Ontario, Canada) and partially sequenced. Sequence analysis of partial sequences (925 bp, GenBank Accession No. FN555137; 719 bp, GenBank Accession No. FN555138) showed maximum identity (97%) with Tomato leaf curl Palampur virus (ToLCPaV) recently reported from India and Iran (1,2). To our knowledge, this is the first report of ToLCPaV in Pakistan and the first report of the virus on bitter gourd. References: (1) J. Heydarnejad et al. Arch. Virol. 154:1015, 2009. (2) Y. Kumar et al. Virus Genes 38:193, 2009. (3) A. H. Malik et al. Plant Pathol. 55:285, 2006. (4) M. G. Murray and W. F. Thompson. Nucleic Acids Res.8:4321, 1980.
First Report of Powdery Mildew Caused by Podosphaera leucotricha on Callery Pear in North America
Authors: Minnis A. M. , Rossman A. Y. , Clement D. L. , Malinoski M. K. , Rane K. K. 
Published: January 2010

Callery pear, often referred to as Bradford pear, is a species native to China that is planted throughout North America as an ornamental tree for its white flowers in spring, bright colored foliage in autumn, and resistance to disease. In some regions it is becoming an invasive species that is replacing native trees. In May 2009, leaves of Pyrus calleryana ‘Cleveland Select’ showing distortion and signs of powdery mildew were collected in Columbia (Howard County), Maryland. A survey of the surrounding area found numerous similarly diseased trees of this cultivar. Microscopic observation of the leaves revealed a fungus with an Oidium anamorph having nipple-shaped appressoria; conidiophores erect, foot cells cylindric, straight, of terminal origin, 41 to 55 × 9.5 to 12.5 μm, with the following cells present in variable numbers; conidia catenulate, broadly ellipsoid to rarely slightly ovoid, 22 to 27 × 11 to 17 μm, with fibrosin bodies. Chasmothecia were absent. On the basis of morphology and host, the fungus was identified as Podosphaera leucotricha (Ellis & Everh.) E.S. Salmon (Leotiomycetes, Erysiphales) (1). The specimen on P. calleryana was deposited in the U.S. National Fungus Collections as BPI 879141. Additional confirmation resulted from a comparison of internal transcribed spacer (ITS) region DNA sequence data (GenBank Accession No. GU122230) obtained with the custom designed primer, Podoprimer Forward (5′-3′ ACTCGTTCTGCGCGGCTGAC), and the ITS4 primer. The sequence of the fungus on Callery pear was identical to available GenBank sequences of P. leucotricha. P. leucotricha is the etiological agent of a powdery mildew disease that occurs on rosaceous plants, primarily Malus and Pyrus. This fungus occurs nearly worldwide (1), and the pathology of the disease on Callery pear is similar to that of known hosts (1,4). To our knowledge, this is the first report of P. leucotricha on Pyrus calleryana in North America. P. leucotricha has been reported previously only once on Callery pear, Pyrus calleryana ‘Chanticleer’, in Hungary (4). Additionally, the powdery mildew fungus was heavily parasitized by Ampelomyces quisqualis Ces. sensu lato, a cosmopolitan coelomycetous mycoparasite of the Erysiphales that is well known on this species (2,3). ITS region DNA sequence data from the Ampelomyces (GenBank Accession No. GU122231) obtained with the ITS1 and ITS4 primers was identical to that of other isolates parasitic on P. leucotricha (2). References: (1) U. Braun. The Powdery Mildews (Erysiphales) of Europe. Gustav Fischer Verlag, Jena, Germany, 1995. (2) C. Liang et al. Fungal Divers. 24:225, 2007. (3) B. C. Sutton. The Coelomycetes. Fungi Imperfecti with Pycnidia, Acervuli and Stromata. Commonwealth Mycological Institute, Kew, England, 1980. (4) L. Vajna and L. Kiss. Plant Dis. 92:176, 2008.
Occurrence of Powdery Mildew Caused by Leveillula taurica on Onion (Allium cepa) in Iran
Authors: Mirzaee M. R. , Mohammadi M. 
Published: January 2010

During September of 2009, leaves of a local cultivar (yellow bulb) of onion (Allium cepa L.) in the late vegetative growth stage were heavily infected with powdery mildew in the Birjand Region (Giuq Sofla), southern Khorasan, Iran. Disease symptoms included circular to oblong, chlorotic to necrotic lesions that were 1 to 2 cm in diameter as well as white and effuse colonies on young and mature leaves. On the basis of microscopic examination, the whitish powdery colonies consisted of conidiophores and conidia. Conidiophores emerged from stomata, singly or branched in groups of two to three, and formed dimorphic conidia. The primary conidia were lanceolate with a narrowed apex (17.5 to 20 × 55.4 to 67.5 μm) and the secondary conidia were cylindrical to ellipsoid (17.5 to 22.5 × 55 to 70 μm). The teleomorph of the fungus was not observed. Leveillula taurica (Lév.) G. Arnaud (anamorph Oidiopsis sicula Scalia) was subsequently identified by the presence of endophytic mycelia emerging through stomata, branched conidiophores, and hyaline, single-celled, dimorphic conidia borne singly (1,3). To confirm pathogenicity, conidia from diseased onion leaves were brushed onto leaves of 35- to 40-day-old onion plants in triplicate. The inoculated plants were subsequently covered with plastic bags for 3 days to maintain high humidity. After 12 to 14 days, symptoms of powdery mildew appeared on the leaves of inoculated plants. No symptoms developed on the noninoculated plants. Powdery mildew caused by L. taurica on onion has previously been reported from the United States, Brazil, Israel, and Sudan (4). Although this pathogen has previously been reported on Allium spp. by Khodaparast et al. (2) in Iran, to our knowledge, this is the first record of powdery mildew of onion (A. cepa L.) from Iran. The disease outbreak has recently been noted on onion in Aryan Shahr, 70 km north of Giuq Sofla where the pathogen was originally identified. Voucher specimens have been deposited at the Fungal Collection of the Ministry of Agriculture, Tehran, Iran. References: (1) L. J. du Toit et al. Online publication. doi:10.1094.PHP/1129-01-HN. Plant Health Progress. 2004. (2) S. A. Khodaparast et al. Rostaniha 4:108, 2003. (3) S. K. Mohan and N. D. Molenaar. Plant Dis. 89:431, 2005. (4) A. Reis et al. Hortic. Bras. 22:758, 2004.
First Report of Southern Blight of Pepper Caused by Sclerotium rolfsii in Southern Spain
Authors: Remesal E. , Lucena C. , Azpilicueta A. , Landa B. B. , Navas-Cortés J. A. 
Published: January 2010

In May 2009, a stem rot of pepper (Capsicum annuum L.) occurred in a 20-ha field in Hacienda de Tarazona, Seville, in southern Spain. Affected plants appeared singly or were grouped in circular patches as much as 8 to 10 m in diameter. Early symptoms consisted of water-soaked lesions on crown and lower stem tissue in contact with the soil. Plant foliage became pale green and wilted, followed by a complete collapse of the plant. A dense white mycelial mat formed on the lower stem and crown with 1- to 2-mm-diameter, spherical, tan-to-dark brown sclerotia. Lower stem pieces of 12 plants with early disease symptoms were surface sterilized in 0.5% NaOCl, dried, transferred to acidified potato dextrose agar, and incubated at 25 ± 1°C in the dark. Fast-growing fungal colonies with white mycelium and abundant sclerotia developed after 6 to 10 days of incubation. On the basis of morphological characters, the fungus was identified as Sclerotium rolfsii Sacc. (2). To confirm the identity of the pathogen, the ribosomal DNA internal transcribed spacer was amplified and sequenced for two isolates (one of the two exact sequences was deposited as GenBank Accession No. GU080230). The sequence was 99% similar to sequences of Athelia rolfsii (S. rolfsii) in GenBank. Pathogenicity of two isolates was determined by placing two oat seeds colonized by each isolate 0.5 to 1 cm from the stem of 2-week-old pepper plants cv. Cristal (one plant per pot, eight replicates). Plants were incubated in a growth chamber maintained at 28 ± 1°C with a 14-h photoperiod of 360 μE·m–2·s–1 and 60 to 90% relative humidity for 10 days. By the sixth day, discoloration and blight of the foliage and stem was observed. Sclerotia formed around the crown and 88% of the plants died 7 days after inoculation. S. rolfsii was recovered from all affected pepper plants. Noninoculated control plants did not develop symptoms. In southern Spain, S. rolfsii is widely distributed in areas of sugar beet production (1). Because of the wide host range of the pathogen, southern blight could become an important disease of vegetable production in southern Spain. References: (1) R. Jordán-Ramírez et al. IOBC/WPRS Bull. 42:101. 2009. (2) J. E. M. Mordue. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 410, 1974.