bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dry Fractionation Methods to Produce Barley Meals Varying in Protein, Beta‐Glucan, and Starch Contents
Authors: Liu KeShun , Barrows Frederic T. , Obert Don 
Published: June 2009

ABSTRACT:  Barley contains several valuable nutrients including beta‐glucan (BG), protein, and starch. Each has additional value when concentrated. Dehulled and hulless barleys were sequentially pearled for 1 to 6 cycles, each with 8% removal. The 6 pearled kernels and the initial kernel were subjected to impact or abrasive milling, followed by sieving with a series of U.S. standard sieves. Results of pearling fines show that protein was most concentrated in the outer area, and decreased all the way toward the core area (near 100% surface removal). Starch showed an opposite trend. BG followed the starch trend, but reached a peak at about 60% surface removal. Upon milling and sieving of kernel samples, genotype and particle size had significant effects on nutrient contents in sieved fractions. The pearling cycle had significant effects on protein and starch contents but little effect on BG content, while the milling method had significant effects on protein and BG contents but little on starch content. Abrasive milling produced sieved fractions with much higher variation in protein content than impact milling, but the opposite effect was observed for shifting BG content. Mass frequency influenced more on recovery rates of nutrients than their concentrations in individual fractions. When the recovery rate was also taken into consideration, pearling alone was found to be the most effective way to enrich protein in barley kernels. However, a combination of pearling with the method of milling and sieving was needed for maximally shifting BG and starch contents.PRACTICAL APPLICATIONS: Although dry fractionation is the method of choice for separating barley into fractions with varying levels of protein, BG, and/or starch, selection of a specific single or combined method is needed for achieving maximum shifts of a particular nutrient. Such information is significant to those who use dry fractionation methods to enrich protein, BG, and/or starch.
Progress in diabetes research in China
Authors: NING Guang , HONG Jie , BI Yufang , GU Weiqiong , ZHANG Yifei , ZHANG Zhiguo , HUANG Yun , WANG Weiqing , LI Xiaoying 
Published: June 2009

AbstractThe prevalence of diabetes, especially Type 2 diabetes mellitus (T2DM), is increasing markedly throughout the world, including in China. Because T2DM and its complications are associated with considerable socioeconomic burden and mortality, there is increasing interest in developing strategies to prevent or delay progression of the disease. In recent decades, many researchers have focused on the mechanism of onset of diabetes, as well as examining the benefits of various interventions in subjects with different glucose tolerance status to prevent or delay development of the disease. In the present article, we focus on five areas (epidemiology, early intervention, insulin sensitivity and β‐cell function, adipocytokines, and traditional Chinese medicine) to review the progress of research into diabetes in China today. The prevalence of diabetes in China is one of the highest in the world. However, with lifestyle interventions and appropriate pharmacological therapies (including traditional Chinese medicine), T2DM may be prevented, well controlled, or even put into remission. Accurate estimation of insulin secretion and insulin sensitivity, as well as better characterization of the physiological function of adipocytokines, could give us a better understanding of the basic mechanisms underlying the onset of diabetes and could lead to better interventions in people with impaired glucose tolerance and T2DM.
Three nuclear genes for phylogenetic, SNP and population genetic studies of molluscs and other invertebrates
Authors: AUDZIJONYTE A. , VRIJENHOEK R. C. 
Published: June 2009

AbstractThe study reports new primers capable of amplifying fragments from three nuclear protein‐coding genes in a variety of deep‐sea molluscs and annelids – adenine nucleotide translocase (Ant), calmodulin (Cal) and cyclophilin A (CycA). The Ant primers appear to be restricted to bivalve molluscs, whereas the Cal and CycA primers also amplified appropriate gene fragments from Lepetodrilus gastropod molluscs and Osedax polychaete worms. The amplified fragment of Cal contains an intron in the molluscs, but no intron was detected in the Ant and CycA fragments from any of the tested animals. DNA sequences generated by the three primer sets exhibited one to 15 single nucleotide polymorphism sites in deep‐sea vesicomyid clams and Osedax boneworms. The observed levels of polymorphism indicate that the genes are likely to be useful in both population genetic and phylogenetic analyses of different invertebrate taxa.
Photodynamic Therapy for
Acinetobacter baumannii
Burn Infections in Mice
Authors: Dai Tianhong , Tegos George P. , Lu Zongshun , Huang Liyi , Zhiyentayev Timur , Franklin Michael J. , Baer David G. , Hamblin Michael R. 
Published: June 2009

ABSTRACT

Multidrug-resistant
Acinetobacter baumannii
infections represent a growing problem, especially in traumatic wounds and burns suffered by military personnel injured in Middle Eastern conflicts. Effective treatment with traditional antibiotics can be extremely difficult, and new antimicrobial approaches are being investigated. One of these alternatives to antimicrobials could be the combination of nontoxic photosensitizers (PSs) and visible light, known as photodynamic therapy (PDT). We report on the establishment of a new mouse model of full-thickness thermal burns infected with a bioluminescent derivative of a clinical Iraqi isolate of
A. baumannii
and its PDT treatment by topical application of a PS produced by the covalent conjugation of chlorin(e6) to polyethylenimine, followed by illumination of the burn surface with red light. Application of 10
8
A. baumannii
cells to the surface of 10-s burns made on the dorsal surface of shaved female BALB/c mice led to chronic infections that lasted, on average, 22 days and that were characterized by a remarkably stable bacterial bioluminescence. PDT carried out on day 0 soon after application of the bacteria gave over 3 log units of loss of bacterial luminescence in a light exposure-dependent manner, while PDT carried out on day 1 and day 2 gave an approximately 1.7-log reduction. The application of PS dissolved in 10% or 20% dimethyl sulfoxide without light gave only a modest reduction in the bacterial luminescence from mouse burns. Some bacterial regrowth in the treated burn was observed but was generally modest. It was also found that PDT did not lead to the inhibition of wound healing. The data suggest that PDT may be an effective new treatment for multidrug-resistant localized
A. baumannii
infections.
Activities of Daptomycin and Vancomycin Alone and in Combination with Rifampin and Gentamicin against Biofilm-Forming Methicillin-Resistant
Staphylococcus aureus
Isolates in an Experimental Model of Endocarditis
Authors: LaPlante Kerry L. , Woodmansee Suzanne 
Published: June 2009

ABSTRACT

The findings of clinical and in vitro research support the theory that infective endocarditis (IE)-causing bacteria form biofilms and that biofilms negatively affect treatment outcomes. The purpose of the present study was to quantify the biofilm formation of methicillin (meticillin)-resistant
Staphylococcus aureus
(MRSA) isolates obtained from patients with IE and to evaluate the in vitro activities of daptomycin and vancomycin alone and in combination with rifampin (rifampicin) or gentamicin while monitoring the isolates for the development of resistance. A high-inoculum, stationary-phase infection model of IE was used to simulate the pharmacokinetics in humans of daptomycin at 6 mg/kg of body weight/day, vancomycin at 1.25 g every 12 h (q12h) alone and in combination with rifampin at 300 mg every 8 h, and gentamicin at 1.3 mg/kg q12h. Two randomly selected clinical MRSA isolates were obtained from patients with IE; both MRSA isolates quantitatively produced biofilms. The time to bactericidal activity in the presence of daptomycin was isolate dependent but was achieved by 24 h for both MRSA isolates. Vancomycin did not achieve bactericidal activity throughout the experiment. At 24, 48, and 72 h, daptomycin-containing regimens had significantly more activity (greater declines in the mean number of CFU/g) than any of the vancomycin-containing regimens (
P =
0.03). Rifampin and gentamicin antagonized or delayed the bactericidal activity of daptomycin (against MRSA B346846 for rifampin and against both isolates for gentamicin) in the first 24 h. Increases in the daptomycin and vancomycin MICs were not observed. We conclude that in an IE model of biofilm-forming MRSA, daptomycin monotherapy has better in vitro activity than daptomycin in combination with rifampin or gentamicin or any vancomycin-containing regimen studied within the first 24 h. Further investigations are needed to understand the initial delay in bactericidal activity observed when gentamicin or rifampin is combined with daptomycin.
Population Pharmacokinetics of Lumefantrine in Pregnant Women Treated with Artemether-Lumefantrine for UncomplicatedPlasmodium falciparumMalaria
Authors: Tarning Joel , McGready Rose , Lindegardh Niklas , Ashley Elizabeth A. , Pimanpanarak Mupawjay , Kamanikom Benjamas , Annerberg Anna , Day Nicholas P. J. , Stepniewska Kasia , Singhasivanon Pratap , White Nicholas J. , Nosten François 
Published: June 2009

ABSTRACTArtemether-lumefantrine has become one of the most widely used antimalarial drugs in the world. The objective of this study was to determine the population pharmacokinetic properties of lumefantrine in pregnant women with uncomplicated multidrug-resistantPlasmodium falciparummalaria on the northwestern border of Thailand. Burmese and Karen women (n= 103) withP. falciparummalaria and in the second and third trimesters of pregnancy were treated with artemether-lumefantrine (80/480 mg) twice daily for 3 days. All patients provided five capillary plasma samples for drug quantification, and the collection times were randomly distributed over 14 days. The concentration-time profiles of lumefantrine were assessed by nonlinear mixed-effects modeling. The treatment failure rate (PCR-confirmed recrudescent infections at delivery) was high; 16.5% (95% confidence interval, 9.9 to 25.1). The population pharmacokinetics of lumefantrine were described well by a two-compartment open model with first-order absorption and elimination. The final model included interindividual variability in all pharmacokinetic parameters and a linear covariate relationship between the estimated gestational age and the central volume of distribution. A high proportion of all women (40%, 41/103) had day 7 capillary plasma concentrations of <355 ng/ml (which corresponds to approximately <280 ng/ml in venous plasma), a threshold previously associated with an increased risk of therapeutic failure in nonpregnant patients in this area. Predictive modeling suggests that a twice-daily regimen given for 5 days would be preferable in later pregnancy. In conclusion, altered pharmacokinetic properties of lumefantrine contribute to the high rates of failure of artemether-lumefantrine treatment in later pregnancy. Dose optimization is urgently needed.
Role of the
Mycobacterium tuberculosis
P55 Efflux Pump in Intrinsic Drug Resistance, Oxidative Stress Responses, and Growth
Authors: Ramón-García Santiago , Martín Carlos , Thompson Charles J. , Aínsa José A. 
Published: June 2009

ABSTRACT

Bacterial efflux pumps have traditionally been studied as low-level drug resistance determinants. Recent insights have suggested that efflux systems are often involved with fundamental cellular physiological processes, suggesting that drug extrusion may be a secondary function. In
Mycobacterium tuberculosis
, little is known about the physiological or drug resistance roles of efflux pumps. Using
Mycobacterium bovis
BCG as a model system, we showed that deletion of the
Rv1410c
gene encoding the P55 efflux pump made the strain more susceptible to a range of toxic compounds, including rifampin (rifampicin) and clofazimine, which are first- and second-line antituberculosis drugs. The efflux pump inhibitors carbonyl cyanide
m
-chlorophenylhydrazone (CCCP) and valinomycin inhibited the P55-determined drug resistance, suggesting the active export of the compounds by use of the transmembrane proton and electrochemical gradients as sources of energy. In addition, the P55 efflux pump mutant was more susceptible to redox compounds and displayed increased intracellular redox potential, suggesting an essential role of the efflux pump in detoxification processes coupled to oxidative balance within the cell. Finally, cells that lacked the
p55
gene displayed smaller colony sizes and had a growth defect in liquid culture. This, together with an increased susceptibility to the cell wall-targeting compounds bacitracin and vancomycin, suggested that P55 is needed for proper cell wall assembly and normal growth in vitro. Thus, P55 plays a fundamental role in oxidative stress responses and in vitro cell growth, in addition to contributing to intrinsic antibiotic resistance. Inhibitors of the P55 efflux pump could help to improve current treatments for tuberculosis.
Candida albicans
and
Staphylococcus aureus
Form Polymicrobial Biofilms: Effects on Antimicrobial Resistance
Authors: Harriott Melphine M. , Noverr Mairi C. 
Published: June 2009

ABSTRACT

Candida albicans
readily forms biofilms on the surface on indwelling medical devices, and these biofilms serve as a source of local and systemic infections. It is estimated that 27% of nosocomial
C. albicans
bloodstream infections are polymicrobial, with
Staphylococcus aureus
as the third most common organism isolated in conjunction with
C. albicans
. We tested whether
S. aureus
and
C. albicans
are able to form a polymicrobial biofilm. Although
S. aureus
formed poor monoculture biofilms in serum, it formed a substantial polymicrobial biofilm in the presence of
C. albicans
. In terms of architecture,
S. aureus
formed microcolonies on the surface of the biofilm, with
C. albicans
serving as the underlying scaffolding. In addition,
S. aureus
matrix staining revealed a different phenotype in polymicrobial versus monomicrobial biofilms, suggesting that
S. aureus
may become coated in the matrix secreted by
C. albicans. S. aureus
resistance to vancomycin was enhanced within the polymicrobial biofilm, required viable
C. albicans
, and was in part mediated by
C. albicans
matrix. However, the growth or sensitivity to amphotericin B of
C. albicans
is not altered in the polymicrobial biofilm.
Competitive Inhibition of Renal Tubular Secretion of Gemifloxacin by Probenecid
Authors: Landersdorfer Cornelia B. , Kirkpatrick Carl M. J. , Kinzig Martina , Bulitta Jürgen B. , Holzgrabe Ulrike , Drusano George L. , Sörgel Fritz 
Published: June 2009

ABSTRACTProbenecid interacts with transport processes of drugs at several sites in the body. For most quinolones, renal clearance is reduced by concomitant administration of probenecid. The interaction between gemifloxacin and probenecid has not yet been studied. We studied the extent, time course, site(s), and mechanism of this interaction. Seventeen healthy volunteers participated in a randomized, two-way crossover study. Subjects received 320 mg gemifloxacin as an oral tablet without and with 4.5 g probenecid divided in eight oral doses. Drug concentrations in plasma and urine were analyzed by liquid chromatography-tandem mass spectrometry. WinNonlin was used for noncompartmental analysis, compartmental modeling, and statistics, and NONMEM was used for visual predictive checks. Concomitant administration of probenecid increased plasma gemifloxacin concentrations and amounts excreted in urine compared to baseline amounts. Data are average estimates (percent coefficients of variation). Modeling showed a competitive inhibition of the renal tubular secretion of gemifloxacin by probenecid as the most likely mechanism of the interaction. The estimatedKmandVmaxfor the saturable part of renal elimination were 9.16 mg/liter (20%) and 113 mg/h (21%), respectively. Based on the molar ratio, the affinity for the renal transporter was 10-fold higher for gemifloxacin than for probenecid. Since probenecid reached an ∼200-times-higher area under the molar concentration-time curve from 0 to 24 h than gemifloxacin, probenecid inhibited the active tubular secretion of gemifloxacin. Probenecid also reduced the nonrenal clearance of gemifloxacin from 25.2 (26%) to 21.0 (23%) liters/h. Probenecid inhibited the renal tubular secretion of gemifloxacin, most likely by a competitive mechanism, and slightly decreased nonrenal clearance of gemifloxacin.
Vancomycin and Daptomycin Pharmacodynamics Differ against a Site-Directed
Staphylococcus epidermidis
Mutant Displaying the Small-Colony-Variant Phenotype
Authors: Wu Marina , von Eiff Christof , Al Laham Nahed , Tsuji Brian T. 
Published: June 2009

ABSTRACT

Catheter-related bloodstream infections due to slow-growing
Staphylococcus epidermidis
small-colony variants (SCVs) are extremely difficult to treat. Daptomycin and vancomycin pharmacodynamics were evaluated against a site-directed
hemB
mutant of
S. epidermidis
displaying the SCV phenotype and compared to that of the parental strain. The maximal killing effect decreased by 7.7-fold for vancomycin and 1.5-fold for daptomycin against the SCV mutant and were well characterized by a Hill-type mathematical model (
R
2
> 0.97).
Tuberculosis and Trimethoprim-Sulfamethoxazole
Authors: Forgacs Pierre , Wengenack Nancy L. , Hall Leslie , Zimmerman Sarah K. , Silverman Mark L. , Roberts Glenn D. 
Published: June 2009

ABSTRACTThe sulfonamides were the first drugs with antituberculous effects. Their use was abandoned and basically forgotten with the advent of streptomycin and isoniazid combination treatment. There is a widespread belief, apparently based on testing a single isolate on questionable media, thatMycobacterium tuberculosisis resistant to trimethoprim-sulfamethoxazole (TMP-SMX). We saw a complex immunocompromised patient with tuberculosis who was initially treated with TMP-SMX without antituberculous drugs and defervesced on this treatment. An isolate ofM. tuberculosisfrom this patient was found to be sensitive to TMP-SMX. We examined how frequentlyM. tuberculosisis sensitive to TMP-SMX. Isolates were tested for susceptibility to TMP-SMX on supplemented Middlebrook 7H10 plates. We found that 43 of 44 (98%) isolates ofM. tuberculosiswere susceptible to the combination of ≤1 μg/ml of TMP and 19 μg/ml of SMX (≤1/19 μg/ml). Thus, the vast majority of ourM. tuberculosisisolates were susceptible to TMP-SMX at an MIC similar to that forMycobacterium kansasii,Mycobacterium marinum, and sensitive rapidly growing mycobacteria, organisms successfully treated with TMP-SMX as part of the treatment regimen. It is possible that TMP-SMX may be useful in treating patients with multiple-drug-resistant and extended drug-resistant tuberculosis. We feel that a clinical trial looking at the effectiveness of TMP-SMX as an antituberculous drug is worthwhile.
Strain-Specific Duffy Binding Protein Antibodies Correlate with Protection against Infection with Homologous Compared to Heterologous
Plasmodium vivax
Strains in Papua New Guinean Children
Authors: Cole-Tobian Jennifer L. , Michon Pascal , Biasor Moses , Richards Jack S. , Beeson James G. , Mueller Ivo , King Christopher L. 
Published: June 2009

ABSTRACT

Individuals repeatedly infected with malaria acquire protection from infection and disease; immunity is thought to be primarily antibody-mediated and directed to blood-stage infection. Merozoite surface proteins involved in the invasion of host erythrocytes are likely targets of protective antibodies. We hypothesized that Papua New Guinean children (
n
= 206) who acquire high antibody levels to two
Plasmodium vivax
merozoite proteins, Duffy binding protein region II (PvDBPII) and the 19-kDa C-terminal region of
P. vivax
merozoite surface protein 1 (PvMSP1
19
), would have a delay in the time to reinfection following treatment to clear all blood-stage malaria infections. Ninety-four percent of the children were reinfected with
P. vivax
during biweekly follow-ups for 6 months. Since PvDBPII is polymorphic, we examined whether individuals acquired strain-specific immunity to PvDBPII. Children with high antibody levels to a prevalent PvDBPII allele (O) were associated with a delay in the time to reinfection with the same variant of
P. vivax
by 25% compared to parasites expressing other PvDBPII alleles (age-adjusted hazard ratio, 0.75 [95% confidence interval, 0.56 to 1.00 by Cox regression]) and 39% lower incidence density parasitemia (
P
= 0.01). Two other prevalent alleles (AH and P) showed a similar trend of 16% and 18% protection, respectively, against parasites with the same PvDBPII allele and reduced incidence density parasitemia. Antibodies directed to PvDBPII PNG-P and -O were both associated with a 21 to 26% reduction in the risk of
P. vivax
infections with higher levels of parasitemia (>150 parasites/μl), respectively. There was no association with high antibody levels to PvMSP1
19
and a delay in the time to
P. vivax
reinfection. Thus, anti-PvDBPII antibodies are associated with strain-specific immunity to
P. vivax
and support the use of PvDBPII for a vaccine against
P. vivax
.
Roles of RseB, σ
E
, and DegP in Virulence and Phase Variation of Colony Morphotype of
Vibrio vulnificus
Authors: Brown Roslyn N. , Gulig Paul A. 
Published: June 2009

ABSTRACT

Vibrio vulnificus
is an estuarine bacterium capable of causing serious and often fatal wound infections and primary septicemia. We used alkaline phosphatase insertion mutagenesis to identify genes necessary for the virulence of this pathogen. One mutant had an in-frame fusion of ′
phoA
to the gene encoding RseB, a periplasmic negative regulator of the alternative sigma factor σ
E
. σ
E
controls an extensive regulon involved in responding to cell envelope stresses. Colonies of the
rseB
mutant were less opaque than wild-type colonies and underwent phase variation between translucent and opaque morphologies.
rseB
mutants were attenuated for virulence in subcutaneously inoculated iron-dextran-treated mice. To obtain insight into the role of
rseB
and the extracytoplasmic stress response in
V. vulnificus
, mutants with defined mutations in
rseB
and two important members of the extracytoplasmic stress regulon,
rpoE
and
degP
, were constructed for analysis of virulence, colony morphology, and stress-associated phenotypes. Deletion of
rseB
caused reversible phase variation in the colony morphotype that was associated with extracellular polysaccharides. Translucent and transparent morphotype strains were attenuated for virulence.
rpoE
and
degP
deletion mutants were sensitive to membrane-perturbing agents and heat but were not significantly attenuated for
V. vulnificus
virulence in mice. These results reveal complex relationships between regulation of the extracytoplasmic stress response, exopolysaccharides, and the virulence of
V. vulnificus
.