bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can the EPIC food-frequency questionnaire be used in adolescent populations?
Authors: Lietz Georg , Barton Karen L , Longbottom Patricia J , Anderson Annie S 
Published: February 2003

AbstractObjective:To assess the validity of the food-frequency questionnaire used in the European Prospective Investigation of Cancer (EPIC FFQ) for estimating nutrient intake in an adolescent population.Design:Sixty-seven schoolchildren (mean age: 12.3±0.3 years) were recruited to complete a 7-day weighed dietary record (7-day WDR), the EPIC FFQ and supply one 24-hour urine collection.Setting:Harris Academy in Dundee (UK).Results:Fifty subjects completed both dietary assessment methods. Thirteen of these were classified as underreporters with energy intake/basal metabolic rate<1.14. The EPIC FFQ showed higher estimates than the 7-day WDR for all nutrients. The median Spearman correlation coefficient for the nutrients examined was found to be 0.31 and increased to 0.48 after adjustment for total energy. The limits of agreement were as far apart as 13.4 MJ, 120 g, 270 g, 120 g and 1170 mg for energy, fat, sugar, protein and calcium, respectively. Correlations between urine and 7-day WDR dietary nitrogen and potassium were found to be statistically significant with r = 0.45 (P<0.05) and r = 0.78 (P<0.001), respectively. The median proportion of subjects that appeared in the same and opposite third of intake was found to be 45.9% and 10.8%, respectively.Conclusions:The EPIC FFQ seems adequate to correctly classify low, medium and high consumers and might therefore be used to identify adolescent population groups at risk or for differences between populations. However, agreement between the EPIC FFQ and the 7-day WDR was very poor on both a group and an individual basis, and demonstrates that the EPIC FFQ is not an appropriate method for estimating absolute intakes in this age group.
How well do children aged 5–7 years recall food eaten at school lunch?
Authors: Warren Janet M , Henry C Jeya K , Livingstone M Barbara E , Lightowler Helen J , Bradshaw Suzanne M , Perwaiz Sylvia 
Published: February 2003

AbstractObjective:This study aimed to determine the accuracy with which children aged 5 to 7 years were able to report the food eaten at a school lunch.Subjects/setting:Two hundred and three children (103 boys, 100 girls) aged 5–7 years were recruited from three primary schools in Oxford.Design:Trained investigators made observational records of the school dinner and packed lunch intakes of four or five children per session. Children were interviewed within two hours of finishing the lunchtime meal and asked to provide a free recall of their meal. When the child had completed the recall, non-directive prompts were used to assess if the child was able to remember anything else. Foods recalled were classified as matches (recalled food agreed with observation), omissions (failed to report a food observed) or phantoms (recalled food was not observed).Results:The percentage of accurate recall was significantly higher (P<0.01) in children eating packed lunch (mean 70±29%) than in children consuming school dinners (mean 58±27%). This difference may have been due to increased familiarity of foods in packed lunches. Leftovers were not readily reported in this age group. Prompts and cues enhanced recall by all children.Conclusions:This study indicated that there was a wide range in the ability of children aged 5–7 years to recall intake from a packed lunch and/or school dinner. This dietary assessment method is unlikely to be suitable at an individual level. Investigators using dietary recall to estimate food intake in children aged 5–7 years need to be aware of the limitations of this method.
A Diet Quality Index for Pregnancy detects variation in diet and differences by sociodemographic factors
Authors: Bodnar Lisa M , Siega-Riz Anna Maria 
Published: February 2003

AbstractObjective:Methods currently used to assess nutritional status during pregnancy have limitations if one wishes to examine the overall quality of the diet. A Diet Quality Index for Pregnancy (DQI-P) was developed to reflect current nutritional recommendations for pregnancy and national dietary guidelines.Design:Dietary intake was assessed during the second trimester using a food-frequency questionnaire. The DQI-P includes eight components: % recommended servings of grains, vegetables and fruits, % recommendations for folate, iron and calcium, % energy from fat, and meal/snack patterning score. Scores can range from 0 to 80; each component contributed 10 points.Setting:Two public prenatal clinics in central North Carolina.Subjects:N= 2063 pregnant women who participated in the Pregnancy, Infection, and Nutrition (PIN) Study.Results:The DQI-P quantitatively differentiated diets. The mean score for the population was 56.0 (standard deviation 12.0). Women who were <30 years old, <350% of poverty, nulliparous and high school graduates had significantly higher overall DQI-P scores. Higher percentages of recommended vegetable servings were consumed by higher-income, older and better-educated women. Greater percentages of recommended intakes of folate and iron were seen among black, low-income and nulliparous women. Higher iron intakes were also seen among women who graduated high school and were less than 30 years old. Other differences were observed for intake of fat and meal/snack pattern. Because this index was based on national recommendations, the DQI-P may be a useful tool for research and public health settings to evaluating overall diet quality of pregnant women.
Relative efficiency of government and non-government organisations in implementing a nutrition intervention programme – a case study from Bangladesh
Authors: Khan M Mahmud , Ahmed Shakil 
Published: February 2003

AbstractObjective:The Bangladesh Integrated Nutrition Programme (BINP) experimented with two models of delivery: the first model uses the Government of Bangladesh's (GOB) own management structure and the second uses the non-government organisations (NGOs) working in the local community. This study compares the relative efficiency of GOB and NGO management in the provision of nutrition services.Design:A detailed costing survey was carried out to estimate the cost of delivering nutrition services from the Community Nutrition Centres (CNCs). The number of individuals enrolled, the number actually participating in the programme and person-days of service delivered were used as effectiveness measures.Setting:Thirty-five CNCs were randomly selected from five BINP areas, of which 21 were in GOB-run areas and 14 in NGO-run areas.Results:The cost of providing nutrition services per enrolee was US$ 24.43 for GOB-run CNCs and US$ 29.78 for NGO-run CNCs.Conclusions:Contrary to the widely held view, the analysis implies that the NGO facilities are not more efficient in the delivery of nutrition services when cost per person-days of service delivered is considered. The food cost component of BINP is so high that, irrespective of the delivery mode, policy makers should examine carefully the components of BINP in order to find the most cost-effective mix of services.
Effects of Sulfamethizole and Amdinocillin against
Escherichia coli
Strains (with Various Susceptibilities) in an Ascending Urinary Tract Infection Mouse Model
Authors: Kerrn M. B. , Frimodt-Møller N. , Espersen F. 
Published: February 2003

ABSTRACT

Resistance to antibiotics used for the treatment of urinary tract infections (UTIs) is increasing worldwide. The impact of in vitro resistance on clinical outcome in UTIs requires further study, since most studies of both humans and animals have evaluated only the efficacy of antibiotics toward bacteria susceptible in vitro. We were interested in evaluating the relationship between the in vitro antibacterial effect and the in vivo efficacy after antibiotic treatment. We simulated a natural ascending UTI by use of the ascending UTI mouse model and used
Escherichia coli
strains with various susceptibilities to amdinocillin (mecillinam) and sulfamethizole. Mice were treated for 3 days with antibiotic doses approximating human urinary tract concentrations after a standard oral dose. For a susceptible strain (MIC, 0.5 μg/ml) and a resistant strain (MIC, 128 μg/ml), respectively, there were significant reductions in bacterial counts in the urine, bladder, and kidneys after treatment with amdinocillin, whereas for a strain for which the MIC was 16 μg/ml, there was a significant reduction in bacterial counts in the kidneys only (
P
< 0.05). Treatment with sulfamethizole resulted in a significant reduction in bacterial counts in all samples from a susceptible strain (MIC, 128 μg/ml) and a resistant strain (MIC, 512 μg/ml). Infection with a
sulII
gene-positive strain (MIC, >2,048 μg/ml) could not be treated with sulfamethizole, as no effect could be demonstrated in the urine, bladder, or kidneys. For amdinocillin, there was no clear-cut relationship between the in vitro susceptibility and the in vivo outcome, while for sulfamethizole, we found a relationship between the MIC for the strain and the effect in the urinary tract.
Aminoglycoside Nephrotoxicity: Modeling, Simulation, and Control
Authors: Rougier Florent , Claude Daniel , Maurin Michel , Sedoglavic Alexandre , Ducher Michel , Corvaisier Stéphane , Jelliffe Roger , Maire Pascal 
Published: February 2003

ABSTRACTThe main constraints on the administration of aminoglycosides are the risks of nephrotoxicity and ototoxicity, which can lead to acute, renal, vestibular, and auditory toxicities. In the present study we focused on nephrotoxicity. No reliable predictor of nephrotoxicity has been found to date. We have developed a deterministic model which describes the pharmacokinetic behavior of aminoglycosides (with a two-compartment model), the kinetics of aminoglycoside accumulation in the renal cortex, the effects of aminoglycosides on renal cells, the resulting effects on renal function by tubuloglomerular feedback, and the resulting effects on serum creatinine concentrations. The pharmacokinetic parameter values were estimated by use of the NPEM program. The estimated pharmacodynamic parameter values were obtained after minimization of the least-squares objective function between the measured and the calculated serum creatinine concentrations. A simulation program assessed the influences of the dosage regimens on the occurrence of nephrotoxicity. We have also demonstrated the relevancy of modeling of the circadian rhythm of the renal function. We have shown the ability of the model to fit with 49 observed serum creatinine concentrations for a group of eight patients treated for endocarditis by comparison with 49 calculated serum creatinine concentrations (r2= 0.988;P< 0.001). We have found that for the same daily dose, the nephrotoxicity observed with a thrice-daily administration schedule appears more rapidly, induces a greater decrease in renal function, and is more prolonged than those that occur with less frequent administration schedules (for example, once-daily administration). Moreover, for once-daily administration, we have demonstrated that the time of day of administration can influence the incidence of aminoglycoside nephrotoxicity. The lowest level of nephrotoxicity was observed when aminoglycosides were administered at 1:30 p.m. Clinical application of this model might make it possible to adjust aminoglycoside dosage regimens by taking into account both the efficacies and toxicities of the drugs.
Effects of an Efflux Mechanism and Ribosomal Mutations on Macrolide Susceptibility of
Haemophilus influenzae
Clinical Isolates
Authors: Peric Mihaela , Bozdogan Bülent , Jacobs Michael R. , Appelbaum Peter C. 
Published: February 2003

ABSTRACT

This study investigated macrolide resistance mechanisms in clinical
Haemophilus influenzae
strains with different levels of susceptibility to macrolides. A total of 6,382 isolates were collected during the Alexander Project from 1997 to 2000. For 96.9% of these isolates, the azithromycin MICs were 0.25 to 4 μg/ml, and these were defined as baseline strains. For 1.8% of the isolates, the azithromycin MICs were lower (<0.25 μg/ml), and for 1.3% of the isolates, the MICs were higher (>4 μg/ml). These isolates were defined as hypersusceptible and high-level macrolide-resistant strains, respectively. To identify the mechanisms associated with these three susceptibility patterns, representative strains were studied for the presence of macrolide efflux pumps and for ribosomal alterations. Macrolide efflux was studied by measuring the accumulation of radioactive azithromycin and clarithromycin in the presence or absence of carbonyl cyanide
m
-chlorophenylhydrazone (CCCP), a protonophore. Treatment with CCCP increased the accumulation of macrolides in baseline as well as high-level resistant strains, demonstrating the presence of an efflux mechanism, but not in the 20 hypersusceptible strains tested. Among the 31 strains studied that showed high-level resistance to both azithromycin and clarithromycin, 28 had ribosomal alterations, 7 had mutations in ribosomal protein L4, 11 had mutations in L22, 2 had mutations in 23S rRNA, 8 had multiple mutations, and 3 had no mutations. From these results, we conclude that the vast majority (>98%) of
H. influenzae
strains have a macrolide efflux mechanism, with a few of these being hyperresistant (1.3%) due to one or several ribosomal mutations. Occasional hypersusceptible strains (1.8%) were found and had no macrolide resistance mechanisms and appeared to be the only truly macrolide-susceptible variants of
H. influenzae
.
Mutant Prevention Concentration of Garenoxacin (BMS-284756) for Ciprofloxacin-Susceptible or -Resistant
Staphylococcus aureus
Authors: Zhao Xilin , Eisner William , Perl-Rosenthal Nathan , Kreiswirth Barry , Drlica Karl 
Published: February 2003

ABSTRACT

The new quinolone garenoxacin (BMS-284756), which lacks a C-6 fluorine, was examined for its ability to block the growth of
Staphylococcus aureus
. Measurement of the MIC and the mutant prevention concentration (MPC) revealed that garenoxacin was 20-fold more potent than ciprofloxacin for a variety of ciprofloxacin-susceptible isolates, some of which were resistant to methicillin. The MPC for 90% of the isolates (MPC
90
) was below published serum drug concentrations achieved with recommended doses of garenoxacin. These in vitro observations suggest that garenoxacin has a low propensity for selective enrichment of fluoroquinolone-resistant mutants among ciprofloxacin-susceptible isolates of
S. aureus
. For ciprofloxacin-resistant isolates, the MIC at which 90% of the isolates tested were inhibited was below serum drug concentrations while the MPC
90
was not. Thus, for these strains, garenoxacin concentrations are expected to fall inside the mutant selection window (between the MIC and the MPC) for much of the treatment time. As a result, garenoxacin is expected to selectively enrich mutants with even lower susceptibility.
Transcriptional Induction of the Penicillin-Binding Protein 2 Gene in
Staphylococcus aureus
by Cell Wall-Active Antibiotics Oxacillin and Vancomycin
Authors: Boyle-Vavra Susan , Yin Shaohui , Challapalli Mamatha , Daum Robert S. 
Published: February 2003

ABSTRACT

We found an increased abundance of
pbpB
-specific transcripts in vancomycin intermediate-resistant
Staphylococcus aureus
(VISA) isolates compared with that found in paired, genetically identical, susceptible isolates. This difference in expression cannot be explained by differences in the
pbpB
promoter sequence. Since the factors controlling
pbpB
gene expression have remained largely unexplored, various conditions that might affect
pbpB
transcript abundance were examined. In both vancomycin-susceptible and VISA strains,
pbpB
expression varied with the growth phase, with the highest abundance of
pbpB
-specific transcripts detected during mid-log phase. Interestingly, both vancomycin and oxacillin were able to induce
pbpB
transcription above a constitutive level. When vancomycin was absent, one of the three
pbpB
-specific transcripts that were usually faintly detected in non-VISA strains was more readily detected in VISA strains during mid-log but not stationary phase. This transcript was enhanced in non-VISA strains by vancomycin induction. Gel shift assays indicated that an increased amount of the putative transcription factor that binds to both P1 and P1′ promoter regions is present in the cytosol of vancomycin-induced cells. Neither the SigB sigma factor nor the quorum-sensing
agr
locus was required for growth phase-variable
pbpB
expression or transcriptional induction of
pbpB
by vancomycin or oxacillin. Also, MecI, MecR1, BlaI, and BlaR1, regulatory proteins that mediate β-lactam-inducible expression of
mecA
and β-lactamase, were not required for antibiotic induction of
pbpB
transcription. These data support the idea that
pbpB
expression is modulated by a
trans
-acting factor in response to the presence of the cell wall-active antibiotics vancomycin and oxacillin.
Active-Site Residues of
Escherichia coli
DNA Gyrase Required in Coupling ATP Hydrolysis to DNA Supercoiling and Amino Acid Substitutions Leading to Novobiocin Resistance
Authors: Gross Christian H. , Parsons Jonathan D. , Grossman Trudy H. , Charifson Paul S. , Bellon Steven , Jernee James , Dwyer Maureen , Chambers Stephen P. , Markland William , Botfield Martyn , Raybuck Scott A. 
Published: February 2003

ABSTRACT

DNA gyrase is a bacterial type II topoisomerase which couples the free energy of ATP hydrolysis to the introduction of negative supercoils into DNA. Amino acids in proximity to bound nonhydrolyzable ATP analog (AMP · PNP) or novobiocin in the gyrase B (GyrB) subunit crystal structures were examined for their roles in enzyme function and novobiocin resistance by site-directed mutagenesis. Purified
Escherichia coli
GyrB mutant proteins were complexed with the gyrase A subunit to form the functional A
2
B
2
gyrase enzyme. Mutant proteins with alanine substitutions at residues E42, N46, E50, D73, R76, G77, and I78 had reduced or no detectable ATPase activity, indicating a role for these residues in ATP hydrolysis. Interestingly, GyrB proteins with P79A and K103A substitutions retained significant levels of ATPase activity yet demonstrated no DNA supercoiling activity, even with 40-fold more enzyme than the wild-type enzyme, suggesting that these amino acid side chains have a role in the coupling of the two activities. All enzymes relaxed supercoiled DNA to the same extent as the wild-type enzyme did, implying that only ATP-dependent reactions were affected. Mutant genes were examined in vivo for their abilities to complement a temperature-sensitive
E. coli gyrB
mutant, and the activities correlated well with the in vitro activities. We show that the known R136 novobiocin resistance mutations bestow a significant loss of inhibitor potency in the ATPase assay. Four new residues (D73, G77, I78, and T165) that, when changed to the appropriate amino acid, result in both significant levels of novobiocin resistance and maintain in vivo function were identified in
E. coli
.
Influence of P-Glycoprotein Inhibitors on Accumulationof Macrolides in J774 MurineMacrophages
Authors: Seral Cristina , Michot Jean-Michel , Chanteux Hugues , Mingeot-Leclercq Marie-Paule , Tulkens Paul M. , Van Bambeke Françoise 
Published: February 2003

ABSTRACTThe influence of inhibitors of P-glycoprotein (verapamil [VE], cyclosporine [CY], and GF120918 [GF]) on the cell handling of macrolides (erythromycin [ERY], clarithromycin [CLR], roxithromycin [ROX], azithromycin [AZM], and telithromycin [TEL]) was examined in J774 murine macrophages. The net influx rates of AZM and TEL were increased from 2- to 3.5-fold in the presence of these inhibitors, but their efflux was slowed only marginally. At 3 h, the inhibitors increased the levels of AZM, ERY, and TEL accumulation approximately three- to fourfold (the effect of VE, however, was lower) but did not influence CLR accumulation (the inhibitors had an intermediate behavior on ROX accumulation). The effect was concentration dependent (half-maximal increases in the level of accumulation of AZM were obtained with GF, CY, and VE at 0.5, 5, and 10μ M, respectively). ATP depletion also caused an approximately threefold increase in the level of accumulation of AZM. Two inhibitors of MRP (probenecid [2.5 mM] and gemfibrozil [0.25 mM]) had no effect. Monensin (a proton ionophore) completely suppressed the accumulation of AZM in control cells as well as in cells incubated in the presence of VE, demonstrating that transmembrane proton gradients are the driving force causing the accumulation of AZM in both cases. Yet, VE did not alter the pH of the lysosomes (approximately 5) or of the cytosol (approximately 7.1). P-glycoprotein was detected by immunostaining at the cell surface as well as in intracellular vacuoles (endosomes and lysosomes). The data suggest that the influx of AZM, ERY, TEL, and ROX is adversely influenced by the activity of P-glycoprotein in J774 macrophages, resulting in suboptimal drug accumulation.
Structure-Based Design and Engineering of a Nontoxic Recombinant Pokeweed Antiviral Protein with Potent Anti-Human Immunodeficiency Virus Activity
Authors: Uckun Fatih M. , Rajamohan Francis , Pendergrass Sharon , Ozer Zahide , Waurzyniak Barbara , Mao Chen 
Published: February 2003

ABSTRACTA molecular model of pokeweed antiviral protein (PAP)-RNA interactions was used to rationally engineer FLP-102(151AA152) and FLP-105(191AA192) as nontoxic PAPs with potent anti-human immunodeficiency virus (anti-HIV) activities. FLP-102 and FLP-105 have been produced inEscherichia coliand tested both in vitro and in vivo. These proteins depurinate HIV type 1 (HIV-1) RNA much better than rRNA and are more potent anti-HIV agents than native PAP or recombinant wild-type PAP. They are substantially less toxic than native PAP in BALB/c mice and exhibit potent in vivo activities against genotypically and phenotypically nucleoside reverse transcriptase inhibitor-resistant HIV-1 in a surrogate human peripheral blood lymphocyte (Hu-PBL) SCID mouse model of human AIDS. Rationally engineered nontoxic recombinant PAPs such as FLP-102 and FLP-105 may provide the basis for effective salvage therapies for patients harboring highly drug-resistant strains of HIV-1. The documented in vitro potencies of FLP-102 and FLP-105, their in vivo antiretroviral activities in the HIV-infected Hu-PBL SCID mouse model, and their favorable toxicity profiles in BALB/c mice warrant the further development of these promising new biotherapeutic agents.
Amino Acid Sequence Requirements at Residues 69 and 238 for the SME-1 β-Lactamase To Confer Resistance to β-Lactam Antibiotics
Authors: Majiduddin Fahd K. , Palzkill Timothy 
Published: February 2003

ABSTRACT

Carbapenem antibiotics have been used to counteract resistant strains of bacteria harboring β-lactamases and extended-spectrum β-lactamases. Four enzymes from the class A group of β-lactamases, NMC-A, IMI-1, SME-1
,
and KPC-1, efficiently hydrolyze carbapenem antibiotics. Sequence comparisons and structural information indicate that cysteines at amino acid residues 69 and 238, which are conserved in all four of these enzymes, form a disulfide bond that is unique to these β-lactamases. To test whether this disulfide bond is required for catalytic activity, the codons for residues Cys69 and Cys238 were randomized individually and simultaneously by PCR-based mutagenesis to create random replacement libraries for these positions. Mutants that were able to confer resistance to ampicillin, imipenem, or cefotaxime were selected from these libraries. The results indicate that positions Cys69 and Cys238 are critical for hydrolysis of all of the antibiotics tested, suggesting that the disulfide bond is generally required for this enzyme to catalyze the hydrolysis of β-lactam antibiotics.