bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testing DNA barcoding in closely related groups of Lysimachia L. (Myrsinaceae)
Authors: ZHANG CAI‐YUN , WANG FENG‐YING , YAN HAI‐FEI , HAO GANG , HU CHI‐MING , GE XUE‐JUN 
Published: October 2011

AbstractIt has been suggested that rbcL and matK are the core barcodes in plants, but they are not powerful enough to distinguish between closely related plant groups. Additional barcodes need to be evaluated to improve the level of discrimination between plant species. Because of their well‐studied taxonomy and extreme diversity, we used Chinese Lysimachia (Myrsinaceae) species to test the performance of core barcodes (rbcL and matK) and two additional candidate barcodes (trnH‐psbA and the nuclear ribosomal ITS); 97 accessions from four subgenus representing 34 putative Lysimachia species were included in this study. And many closely related species pairs in subgen. Lysimachia were covered to detect their discriminatory power. The inefficiency of rbcL and matK alone or combined in closely related plant groups was validated in this study. TrnH‐psbA combined with rbcL + matK did not yet perform well in Lysimachia groups. In contrast, ITS, alone or combined with rbcL and/or matK, revealed high resolving ability in Lysimachia. We support ITS as a supplementary barcode on the basis of core barcode rbcL and matK. Besides, this study also illustrates several mistakes or underlying evolutionary events in Lysimachia detected by DNA barcoding.
Identification of
fusB
-Mediated Fusidic Acid Resistance Islands in Staphylococcus epidermidis Isolates
Authors: Chen Hsiao-Jan , Tsai Jui-Chang , Hung Wei-Chun , Tseng Sung-Pin , Hsueh Po-Ren , Teng Lee-Jene 
Published: October 2011

ABSTRACT

To understand the high prevalence of
fusB
genes in fusidic acid-resistant
Staphylococcus epidermidis
, analysis of resistance elements in 34 isolates was performed. First, sequence analysis of the
aj1
-LP-
fusB
region indicated that at least three types were present. Type I contained full-length
aj1
, type II contained a partial
aj1
truncated from nucleotide position 93 to 421, and type III contained a more truncated
aj1
that retained only the last 37 bp. Isolates with type I or type II
aj1
displayed slightly higher levels of resistance to fusidic acid (MICs, 8 to 32 μg/ml) than did those with type III
aj1
(MICs, 4 to 16 μg/ml). Subsequent sequencing of the flanking regions of
fusB
from four selected isolates carrying different types of
aj1
-LP-
fusB
regions revealed that the
fusB
genes were all located on phage-related resistance islands (RIs), referred to as SeRI

fusB

-2793
, SeRI

fusB

-704
, SeRI

fusB

-5907
, and SeRI

fusB

-7778
, respectively. Among them, three islands (SeRI

fusB

-2793
, SeRI

fusB

-704
, and SeRI

fusB

-5907
) were located downstream of
groEL
(corresponding to the 44-min position based on
Staphylococcus aureus
whole genomic sequences), and one (SeRI

fusB

-7778
) was located downstream of
rpsR
(corresponding to the 8-min position). All of the RIs were inserted into integrase-recognized
att
sites. Among 34 isolates, the insertion sites of
fusB
RIs were mostly (28/34, 82%) located downstream of
groEL
and two were located downstream of
rpsR
, but four remained unidentified. The pulsotype distribution indicated that
fusB
-containing
S. epidermidis
isolates were heterogeneous. In conclusion, the
fusB
resistance determinant in
S. epidermidis
was highly associated with phage-related RIs. This is the first report of
fusB
RI in
S. epidermidis
.
Polyethylenimine Is a Strong Inhibitor of Human Papillomavirus and Cytomegalovirus Infection
Authors: Spoden Gilles A. , Besold Katrin , Krauter Steffi , Plachter Bodo , Hanik Nils , Kilbinger Andreas F. M. , Lambert Carsten , Florin Luise 
Published: October 2011

ABSTRACT
Polyethylenimines are cationic polymers with potential as delivery vectors in gene therapy and with proven antimicrobial activity. However, the antiviral activity of polyethylenimines has not been addressed in detail thus far. We have studied the inhibitory effects of a linear 25-kDa polyethylenimine on infections with human papillomaviruses and human cytomegaloviruses. Preincubation of cells with polyethylenimine blocked primary attachment of both viruses to cells, resulting in a significant reduction of infection. In addition, the dissemination of human cytomegalovirus in culture cells was efficiently reduced by recurrent administration of polyethylenimine. Polyethylenimine concentrations required for inhibition of human papillomavirus and cytomegalovirus did not cause any cytotoxic effects. Polyethylenimines and their derivatives may thus be attractive molecules for the development of antiviral microbicides.
Relationship of
agr
Expression and Function with Virulence and Vancomycin Treatment Outcomes in Experimental Endocarditis Due to Methicillin-Resistant Staphylococcus aureus
Authors: Seidl Kati , Chen Liang , Bayer Arnold S. , Hady Wessam Abdel , Kreiswirth Barry N. , Xiong Yan Q. 
Published: October 2011

ABSTRACT

The accessory gene regulator (
agr
) locus has been shown to be important for virulence in several animal models of
Staphylococcus
aureus
infection. However, the role of
agr
in human infections, and specifically in antibiotic treatment, is controversial. Interestingly,
agr
dysfunction has been associated with reduced vancomycin responses. To systematically investigate the role of
agr
in virulence and treatment outcome in the context of endovascular infection, 10 well-characterized vancomycin-susceptible methicillin-resistant
S. aureus
(MRSA) bloodstream isolates (5
agr-I
[clonal complex 45, or CC45] and 5
agr-II
[CC5]) were studied for (i)
agr
function, (ii) RNAIII transcriptional profiles, (iii)
agr
locus sequences, (iv) intrinsic virulence and responses to vancomycin therapy in an experimental infective endocarditis (IE) model, and (v)
in vivo
RNAIII expression. Significant differences in
agr
function (determined by delta-hemolysin activity) correlated with the time point of RNAIII transcription (earlier RNAIII onset equals increased
agr
function). Unexpectedly, four MRSA strains with strong delta-hemolysin activities exhibited significant resistance to vancomycin treatment in experimental IE. In contrast, five of six MRSA strains with weak or no delta-hemolysin activity were highly susceptible to vancomycin therapy in the IE model.
agr
sequence analyses showed no common single-nucleotide polymorphism predictive of
agr
functionality.
In vivo
RNAIII expression in cardiac vegetations did not correlate with virulence or vancomycin treatment outcomes in the IE model. Inactivation of
agr
in two strains with strong delta-hemolysin activity did not affect virulence or the
in vivo
efficacy of vancomycin. Our findings suggest that
agr
dysfunction does not correlate with vancomycin treatment failures in this experimental IE model in two distinct MRSA genetic backgrounds.
Triple-Combination Antiviral Drug for Pandemic H1N1 Influenza Virus Infection in Critically Ill Patients on Mechanical Ventilation
Authors: Kim Won-Young , Young Suh Gee , Huh Jin Won , Kim Sung-Han , Kim Min-ju , Kim Yun Seong , Kim Hye-Ryoun , Ryu Yon Ju , Han Min Soo , Ko Young Gwan , Chon Gyu Rak , Lee Kwan Ho , Choi Sang-Ho , Hong Sang-Bum ,   for the Korean Society of Critical Care Medicine (KSCCM) H1N1 Collaborative
Published: October 2011

ABSTRACTA recentin vitrostudy showed that the three compounds of antiviral drugs with different mechanisms of action (amantadine, ribavirin, and oseltamivir) could result in synergistic antiviral activity against influenza virus. However, no clinical studies have evaluated the efficacy and safety of combination antiviral therapy in patients with severe influenza illness. A total of 245 adult patients who were critically ill with confirmed pandemic influenza A/H1N1 2009 (pH1N1) virus infection and were admitted to one of the intensive care units of 28 hospitals in Korea were reviewed. Patients who required ventilator support and received either triple-combination antiviral drug (TCAD) therapy or oseltamivir monotherapy were analyzed. A total of 127 patients were included in our analysis. Among them, 24 patients received TCAD therapy, and 103 patients received oseltamivir monotherapy. The 14-day mortality was 17% in the TCAD group and 35% in the oseltamivir group (P= 0.08), and the 90-day mortality was 46% in the TCAD group and 59% in the oseltamivir group (P= 0.23). None of the toxicities attributable to antiviral drugs occurred in either group of our study, including hemolytic anemia and hepatic toxicities related to the use of ribavirin. Logistic regression analysis indicated that the odds ratio for the association of TCAD with 90-day mortality was 0.58 (95% confidence interval, 0.24 to 1.42;P= 0.24). Although this study was retrospective and did not provide virologic outcomes, our results suggest that the treatment outcome of the triple combination of amantadine, ribavirin, and oseltamivir was comparable to that of oseltamivir monotherapy.
Plasma Drug Activity Assay for Treatment Optimization in Tuberculosis Patients
Authors: Heysell Scott K. , Mtabho Charles , Mpagama Stellah , Mwaigwisya Solomon , Pholwat Suporn , Ndusilo Norah , Gratz Jean , Aarnoutse Rob E. , Kibiki Gibson S. , Houpt Eric R. 
Published: October 2011

ABSTRACT

Low antituberculosis (TB) drug levels are common, but their clinical significance remains unclear, and methods of measurement are resource intensive. Subjects initiating treatment for sputum smear-positive pulmonary TB were enrolled from Kibong'oto National TB Hospital, Tanzania, and levels of isoniazid, rifampin, ethambutol, and pyrazinamide were measured at the time of typical peak plasma concentration (
C
2 h
). To evaluate the significance of the effect of observed drug levels on
Mycobacterium tuberculosis
growth, a plasma TB drug activity (TDA) assay was developed using the Bactec MGIT system. Time to detection of plasma-cocultured
M. tuberculosis
versus time to detection of control growth was defined as a TDA ratio. TDA assays were later performed using the subject's own
M. tuberculosis
isolate and
C
2 h
plasma from the Tanzanian cohort and compared to drug levels and clinical outcomes. Sixteen subjects with a mean age of 37.8 years ± 10.7 were enrolled. Fourteen (88%) had
C
2 h
rifampin levels and 11 (69%) had isoniazid levels below 90% of the lower limit of the expected range. Plasma spiked with various concentrations of antituberculosis medications found TDA assay results to be unaffected by ethambutol or pyrazinamide. Yet with a range of isoniazid and rifampin concentrations, TDA exhibited a statistically significant correlation with drug level and drug MIC, and a TDA of ∼1.0 indicated the presence of multidrug-resistant TB. In Tanzania, low (≤2.0) TDA was significantly associated with both lower isoniazid and rifampin
C
2 h
levels, and very low (≤1.5) TDA corresponded to a trend toward lack of cure. Study of TDA compared to additional clinical outcomes and as a therapeutic management tool is warranted.
Naturally Acquired Immune Responses to Plasmodium falciparum Sexual Stage Antigens Pfs48/45 and Pfs230 in an Area of Seasonal Transmission
Authors: Ouédraogo André Lin , Roeffen Will , Luty Adrian J. F. , de Vlas Sake J. , Nebie Issa , Ilboudo-Sanogo Edith , Cuzin-Ouattara Nadine , Teleen Karina , Tiono Alfred B. , Sirima Sodiomon Bienvenu , Verhave Jan-Peter , Bousema Teun , Sauerwein Robert 
Published: October 2011

ABSTRACT

Acquisition of immunity to
Plasmodium falciparum
sexual stages is a key determinant for reducing human-mosquito transmission by preventing the fertilization and the development of the parasite in the mosquito midgut. Naturally acquired immunity against sexual stages may therefore form the basis for the development of transmission-blocking vaccines, but studies conducted to date offer little in the way of consistent findings. Here, we describe the acquisition of antigametocyte immune responses in malaria-exposed individuals in Burkina Faso. A total of 719 blood samples were collected in a series of three cross-sectional surveys at the start, peak, and end of the wet season. The seroprevalence of antibodies with specificity for the sexual stage antigens Pfs48/45 and Pfs230 was 2-fold lower (22 to 28%) than that for an asexual blood stage antigen glutamate-rich protein (GLURP) (65%) or for the preerythrocytic stage antigen circumsporozoite protein (CSP) (54%). The youngest children responded at frequencies similar to those for all four antigens but, in contrast with the immune responses to GLURP and CSP that increased with age independently of season and area of residence, there was no evidence for a clear age dependence of responses to Pfs48/45 and Pfs230. Anti-Pfs230 antibodies were most prevalent at the peak of the wet season (
P
< 0.001). Our findings suggest that naturally acquired immunity against Pfs48/45 and Pfs230 is a function of recent exposure rather than of cumulative exposure to gametocytes.
Live Attenuated Shigella dysenteriae Type 1 Vaccine Strains Overexpressing Shiga Toxin B Subunit
Authors: Wu Tao , Grassel Christen , Levine Myron M. , Barry Eileen M. 
Published: October 2011

ABSTRACT

Shigella dysenteriae
serotype 1 (
S. dysenteriae
1) is unique among the
Shigella
species and serotypes in the expression of Shiga toxin which contributes to more severe disease sequelae and the ability to cause explosive outbreaks and pandemics.
S. dysenteriae
1 shares characteristics with other
Shigella
species, including the capability of causing clinical illness with a very low inoculum (10 to 100 CFU) and resistance to multiple antibiotics, underscoring the need for efficacious vaccines and therapeutics. Following the demonstration of the successful attenuating capacity of deletion mutations in the
guaBA
operon in
S. flexneri
2a vaccine strains in clinical studies, we developed a series of
S. dysenteriae
1 vaccine candidates containing the fundamental attenuating mutation in
guaBA.
All strains are devoid of Shiga toxin activity by specific deletion of the gene encoding the StxA subunit, which encodes enzymatic activity. The StxB subunit was overexpressed in several derivatives by either plasmid-based constructs or chromosomal manipulation to include a strong promoter. All strains are attenuated for growth
in vitro
in the HeLa cell assay and for plaque formation and were safe in the Serény test and immunogenic in the guinea pigs. Each strain induced robust serum and mucosal anti-
S. dysenteriae
1 lipopolysaccharide (LPS) responses and protected against wild-type challenge. Two strains engineered to overexpress StxB induced high titers of Shiga toxin neutralizing antibodies. These candidates demonstrate the potential for a live attenuated vaccine to protect against disease caused by
S. dysenteriae
1 and potentially to protect against the toxic effects of other Shiga toxin 1-expressing pathogens.
Factors affecting individual variation in nest-defense intensity in colonially breeding Black-tailed Gulls (Larus crassirostris)
Authors: Kazama Kentaro , Niizuma Yasuaki , Sakamoto Kentaro Q. , Watanuki Yutaka 
Published: October 2011

The physiological state of parent birds combined with the value of their clutch may affect the intensity of their nest defense. In colonially breeding birds, nest-defense intensity may also be affected by the behavior of neighbors. We investigated individual variation in the nest-defense intensity among colonial Black-tailed Gulls ( Larus crassirostris Vieillot, 1818) over 2 years. Only 30%–40% of males attacked a decoy of an egg predator (Large-billed Crow ( Corvus macrorhynchos Wagler, 1827)), and the other males and females rarely attacked. Males attacking the decoy had higher levels of plasma testosterone than males that did not attack. Each male’s, but not female’s, nest-defense intensity was consistent throughout the incubation period and also across years. The intensity was not related to egg-laying date, clutch size, or age of offspring. The intensity was likely to be higher when individuals had one or more neighbors, representing higher nest-defense intensity in the year where gulls had larger number of adjacent neighboring nests (5.23 nests), but this trend was not observed in the year where they had smaller number of the neighboring nests (3.73 nests). Thus, in addition to testosterone levels, behavior of neighbors also influences the nest-defense intensity.
Reproduction and denning by urban and rural San Clemente Island foxes (Urocyon littoralis clementae)
Authors: Gould N.P. , Andelt W.F. 
Published: October 2011

Island foxes ( Urocyon littoralis (Baird, 1858)) have experienced severe reductions in populations on 4 out of 6 California Channel Islands. Although numbers of foxes on San Clemente Island (SCLI; Urocyon littoralis clementae Merriam, 1903) have remained relatively stable, data on reproductive success in urban and rural areas are necessary to better understand population dynamics of foxes and manage the population if it sustains declines. Determining locations and characteristics of den sites will also assist in minimizing possible impacts of humans on foxes. We found that 10 female foxes produced at least 19 kits during 2008. Female foxes that spent a greater proportion of time within an urban area had greater probability of reproducing compared with foxes that infrequently utilized urban areas. However, these “urban” foxes often selected den sites nearer to roads, which may expose them to increased mortalities. We located 23 den sites on a mean of 17°–18° slopes with 40% having westerly facing aspects. We recommend avoiding human disturbance to these areas from February through June, which may minimize potential impacts on foxes. Our study should provide insight into managing island foxes, especially in respect to urban areas on other Channel Islands.
Food limitation causes female haglids to mate more often
Authors: Judge Kevin A. , De Luca Paul A. , Morris Glenn K. 
Published: October 2011

Sexual conflict over mating rate has selected for male adaptations to induce females to mate. These inducements can be either coercive or enticing, and there is a growing realization that males of a given species may employ both tactics simultaneously to acquire mating success. Insects in the genus Cyphoderris Uhler, 1864 (Orthoptera: Haglidae) have a unique breeding system in which females feed on the fleshy hind wings of males during copulation, but as mating proceeds males use a specialized abdominal pinching organ known as a gin trap to hold the female until she copulates with him. Previous research has demonstrated the coercive nature of the gin trap, but evidence for a beneficial effect of hind-wing feeding is lacking. Here we tested whether hind-wing feeding provides material benefits to females by manipulating females’ access to nutrition—food restricted or ad lib food—and then providing females with four opportunities to mate over 8 days. As predicted, food-restricted females were more likely to feed on male hind wings, did more hind-wing damage, and were more likely to copulate with males than females provided ad lib food. We discuss these results in the context of the evolution of polyandry and sexual conflict.
Formal Reasoning about Physical Properties of Security Protocols
Authors: Basin David , Capkun Srdjan , Schaller Patrick , Schmidt Benedikt 
Published: October 2011

Traditional security protocols are mainly concerned with authentication and key establishment and rely on predistributed keys and properties of cryptographic operators. In contrast, new application areas are emerging that establish and rely on properties of the physical world. Examples include protocols for secure localization, distance bounding, and secure time synchronization.
We present a formal model for modeling and reasoning about such physical security protocols. Our model extends standard, inductive, trace-based, symbolic approaches with a formalization of physical properties of the environment, namely communication, location, and time. In particular, communication is subject to physical constraints, for example, message transmission takes time determined by the communication medium used and the distance between nodes. All agents, including intruders, are subject to these constraints and this results in a distributed intruder with restricted, but more realistic, communication capabilities than those of the standard Dolev-Yao intruder. We have formalized our model in Isabelle/HOL and have used it to verify protocols for authenticated ranging, distance bounding, broadcast authentication based on delayed key disclosure, and time synchronization.
Agency theory and consultant management in enterprise resource planning systems implementation
Authors: Basu Vedabrata , Lederer Al 
Published: October 2011

Enterprise resource planning (ERP) systems are rapidly becoming the foundations to the decision support systems of many organizations, but have all too often failed to deliver their expected benefits. Most ERP implementation projects are carried out using implementation consultants hired from outside the client firm. The current study treated the consultants as agents and the clients as principals, and applied agency theory to test the consultant-client relationship as a predictor of ERP implementation project success.A survey collected responses from 192 client project managers who worked on the ERP implementation process in their organizations. Data analysis via structural equation modeling showed that more consultant monitoring predicts less moral hazard (i.e., consultant shirking), that less moral hazard predicts greater ERP project success, and that more monitoring directly predicts such success. However, the analysis failed to support expectations that more pre-qualification efforts (i.e., screening of the consultant) would lead to less adverse selection (i.e., the consultant's misrepresentation of skills) or that less adverse selection would lead to greater ERP success. Surprisingly greater incentive alignment predicted greater moral hazard, thus suggesting the potential of incentives to de-motivate rather than motivate.This study contributed by extending agency theory to outsourced information systems project implementation. It provided new, validated measures of prequalification efforts, monitoring, incentive alignment, moral hazard, and adverse selection constructs. The findings suggest that future researchers may want to learn more about incentive alignment and its impact, and that information systems project managers may want to monitor more to improve ERP and other large-scale system implementation success.