bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chloroquine enhances the chemotherapeutic activity of 5‐fluorouracil in a colon cancer cell line via cell cycle alteration
Authors: Choi Jung‐Hye , Yoon Jin Sun , Won Young‐Woong , Park Byeong‐Bae , Lee Young Yiul 
Published: February 2012

Autophagy is a conserved catabolic process that degrades cytoplasmic proteins and organelles for recycling. The role of autophagy in tumorigenesis is controversial because autophagy can be either protective or damaging to tumor cells, and its effects may change during tumor progression. A number of cancer cell lines have been exposed to chloroquine, an anti‐malarial drug, with the aim of inhibiting cell growth and inducing cell death. In addition, chloroquine inhibits a late phase of autophagy. This study was conducted to investigate the anti‐cancer effect of autophagy inhibition, using chloroquine together with 5‐fluorouracil (5‐FU) in a colon cancer cell line. Human colon cancer DLD‐1 cells were treated with 5‐FU (10 μΜ) or chloroquine (100 μΜ), or a combination of both. Autophagy was evaluated by western blot analysis of microtubule‐associated protein light chain3 (LC3). Proliferative activity, alterations of the cell cycle, and apoptosis were measured by MTT assays, flow cytometry, and western blotting. LC3‐II protein increased after treatment with 5‐FU, and chloroquine potentiated the cytotoxicity of 5‐FU. MTT assays showed that 5‐FU inhibited proliferation of the DLD‐1 cells and that chloroquine enhanced this inhibitory effect of 5‐FU. The combination of 5‐FU and chloroquine induced G1 arrest, up‐regulation of p27 and p53, and down‐regulation of CDK2 and cyclin D1. These results suggest that chloroquine may potentiate the anti‐cancer effect of 5‐FU via cell cycle inhibition. Chloroquine potentiates the anti‐cancer effect of 5‐FU in colon cancer cells. Supplementation of conventional chemotherapy with chloroquine may provide a new cancer therapy modality.
Type III apparatus of Pseudomonas aeruginosa as a tool to diagnose pulmonary infection in cystic fibrosis patients
Authors: Cruz Aline C. , Neves Bianca C. , Higa Laurinda Y. S. , Folescu Tânia , Marques Elizabeth A. , Milagres Lucimar G. 
Published: February 2012

Pseudomonas aeruginosa is associated with increased mortality in cystic fibrosis (CF) patients, and expresses type III secretion system proteins (TTSP), which is a common mechanism used by gram‐negative pathogens for delivery of anti‐host factors. Our aim was to investigate whether or not these antigens (TTSP) would be recognized by CF sera, by Western blot reaction. We have showed herein that all patients (n = 11) not chronically infected by P. aeruginosa had their first serum positive for TTSP (ExoS, ExoT, PopB, and/or PopD). All chronic patients had a strong positive serology to TTSP, although relatively weak reactions to TTSP were observed for some individuals in the negative control group. Therefore, TTSP that were early produced in P. aeruginosa infected CF patients, induced a detectable antibody response in those patients and were easily detected by Western‐blot reaction.
The green tea polyphenol (−)‐epigallocatechin gallate precipitates salivary proteins including alpha‐amylase: biochemical implications for oral health
Authors: Hara Kumiko , Ohara Masaru , Hayashi Ikue , Hino Takamune , Nishimura Rumi , Iwasaki Yoriko , Ogawa Tetsuji , Ohyama Yoshihiko , Sugiyama Masaru , Amano Hideaki 
Published: February 2012

Hara K, Ohara M, Hayashi I, Hino T, Nishimura R, Iwasaki Y, Ogawa T, Ohyama Y, Sugiyama M, Amano H. The green tea polyphenol (−)‐epigallocatechin gallate precipitates salivary proteins including alpha‐amylase: biochemical implications for oral health.

Eur J Oral Sci 2012; 120: 132–139. © 2012 Eur J Oral SciGreen tea is a popular drink throughout the world, and it contains various components, including the green tea polyphenol (−)‐epigallocatechin gallate (EGCG). Tea interacts with saliva upon entering the mouth, so the interaction between saliva and EGCG interested us, especially with respect to EGCG–protein binding. SDS‐PAGE revealed that several salivary proteins were precipitated after adding EGCG to saliva. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) peptide mass fingerprinting indicated that the major proteins precipitated by EGCG were alpha‐amylase, S100, and cystatins. Surface plasmon resonance revealed that EGCG bound to alpha‐amylase at dissociation constant (Kd) = 2.74 × 10−6 M, suggesting that EGCG interacts with salivary proteins with a relatively strong affinity. In addition, EGCG inhibited the activity of alpha‐amylase by non‐competitive inhibition, indicating that EGCG is effective at inhibiting the formation of fermentable carbohydrates involved in caries formation. Interestingly, alpha‐amylase reduced the antimicrobial activity of EGCG against the periodontal bacterium Aggregatibacter actinomycetemcomitans. Therefore, we considered that EGCG–salivary protein interactions might have both protective and detrimental effects with respect to oral health.
Microbial profiles in saliva from children with and without caries in mixed dentition
Authors: Luo AH , Yang DQ , Xin BC , Paster BJ , Qin J 
Published: February 2012

Oral Diseases (2012) 18, 595–601Objective:  The purpose of this study was to determine the bacterial profiles in saliva of the isolated children for studying caries etiology.Materials and methods:  Samples were collected from isolated children from 6 to 8 years old including 20 caries‐free (dmfs = 0) (healthy) and 30 caries‐active individuals (dmfs > 8) (patients). 16S rRNA genes were amplified by PCR from bacterial DNA of saliva sample and labeled via incorporation of Cy3‐dCTP in second nested PCR. After hybridization of labeled amplicons on HOMIM, the microarray slides were scanned and original data acquired from professional software.Results:  Collectively, 94 bacterial species or clusters representing six bacterial phyla and 30 genera were detected. A higher bacterial diversity was observed in patients than in healthy samples. Statistical analyses revealed eight species or clusters were detected more frequently in diseased patients than in healthy samples, while six different species were detected more frequently in healthy as compared to diseased patients.Conclusion:  The diversity of microbe within saliva derived from isolated population increased in caries‐active status, and there are some bacteria in salivary flora can be as candidate biomarkers for caries prognosis in mixed dentition. The imbalances in the resident microflora may be the ultimate mechanism of dental caries.
Role of phosphate in the central metabolism of two lactic acid bacteria – a comparative systems biology approach
Authors: Levering Jennifer , Musters Mark W. J. M. , Bekker Martijn , Bellomo Domenico , Fiedler Tomas , de Vos Willem M. , Hugenholtz Jeroen , Kreikemeyer Bernd , Kummer Ursula , Teusink Bas 
Published: February 2012

Lactic acid‐producing bacteria survive in distinct environments, but show common metabolic characteristics. Here we studied the dynamic interactions of the central metabolism in Lactococcus lactis, extensively used as a starter culture in the dairy industry, and Streptococcus pyogenes, a human pathogen. Glucose‐pulse experiments and enzymatic measurements were performed to parameterize kinetic models of glycolysis. Significant improvements were made to existing kinetic models for L. lactis, which subsequently accelerated the development of the first kinetic model of S. pyogenes glycolysis. The models revealed an important role for extracellular phosphate in the regulation of central metabolism and the efficient use of glucose. Thus, phosphate, which is rarely taken into account as an independent species in models of central metabolism, should be considered more thoroughly in the analysis of metabolic systems in the future. Insufficient phosphate supply can lead to a strong inhibition of glycolysis at high glucose concentrations in both species, but this was more severe in S. pyogenes. S. pyogenes is more efficient at converting glucose to ATP, showing a higher tendency towards heterofermentative energy metabolism than L. lactis. Our comparative systems biology approach revealed that the glycolysis of L. lactis and S. pyogenes have similar characteristics, but are adapted to their individual natural habitats with respect to phosphate regulation.DatabaseThe mathematical models described here have been submitted to the Online Cellular Systems Modelling Database and can be accessed at http://jjj.biochem.sun.ac.za/database/Levering/index.html free of charge.
FMN fluorescence in inducible NOS constructs reveals a series of conformational states involved in the reductase catalytic cycle
Authors: Ghosh Dipak K. , Ray Krishanu , Rogers Albert J. , Nahm Nicholas J. , Salerno John C. 
Published: February 2012

Nitric oxide synthases (NOSs) produce NO as a molecular signal in the nervous and cardiovascular systems and as a cytotoxin in the immune response. NO production in the constitutive isoforms is controlled by calmodulin regulation of electron transfer. In the tethered shuttle model for NOS reductase function, the FMN domain moves between NADPH dehydrogenase and oxygenase catalytic centers. Crystal structures of neuronal NOS reductase domain and homologs correspond to an ‘input state’, with FMN in close contact with FAD. We recently produced two domain ‘output state’ (oxyFMN) constructs showing calmodulin dependent FMN domain association with the oxygenase domain. FMN fluorescence is sensitive to enzyme conformation and calmodulin binding. The inducible NOS (iNOS) oxyFMN construct is more fluorescent than iNOS holoenzyme. The difference in steady state fluorescence is rationalized by the observation of a series of characteristic states in the two constructs, which we assign to FMN in different environments. OxyFMN and holoenzyme share open conformations with an average lifetime of ∼ 4.3 ns. The majority state in holoenzyme has a short lifetime of ∼ 90 ps, probably because of FAD–FMN interactions. In oxyFMN about 25–30% of the FMN is in a state with a lifetime of 0.9 ns, which we attribute to quenching by heme in the output state. Occupancy of the output state together with our previous kinetic results yields a heme edge to FMN distance estimate of 12–15 Å. These results indicate that FMN fluorescence is a valuable tool to study conformational states involved in the NOS reductase catalytic cycle.Database
NOS, EC 1.14.13.39
Birth weight, early weight gain and pubertal maturation: a longitudinal study
Authors: Wang Y. , Dinse G. E. , Rogan W. J. 
Published: February 2012

SummaryObjectiveTo investigate the effect of birth weight and early weight gain on the timing of various measures of puberty in both girls and boys.MethodsA total of 856 newborns enrolled in the North Carolina Infant Feeding Study were followed to age 5 years, with 600 children followed up at adolescence. Birth weight was obtained from medical records and children were weighed at study visits until age 5 years; gains in standardized weights were calculated over four early age intervals: 0–6 months, 6–12 months, 1–2 years and 2–5 years. Age at menarche in girls and age at advanced Tanner stages in both girls and boys were reported by adolescents and their parents. Survival models were used to analyse the effects of birth weight and early weight gain on these outcomes.esultsGirls with higher birth weight and greater weight gains during the four early age intervals were younger when they reached menarche and advanced Tanner stages; boys with greater early weight gains also were younger when they reached advanced Tanner stages, but few of these effects were statistically significant.ConclusionsHigher birth weights and greater weight gains during infancy and early childhood can lead to earlier sexual maturation in girls.
Gestational weight gain and predicted changes in offspring anthropometrics between early infancy and 3 years
Authors: Deierlein A. L. , Siega‐Riz A. M. , Herring A. H. , Adair L. S. , Daniels J. L. 
Published: February 2012

SummaryObjectiveTo determine how gestational weight gain (GWG), categorized using the 2009 Institute of Medicine recommendations, relates to changes in offspring weight‐for‐age (WAZ), length‐for‐age (LAZ) and weight‐for‐length z‐scores (WLZ) between early infancy and 3 years.MethodsWomen with singleton infants were recruited from the third cohort of the Pregnancy, Infection, and Nutrition Study (2001–2005). Term infants with at least one weight or length measurement during the study period were included (n = 476). Multivariable linear mixed effects regression models estimated longitudinal changes in WAZ, LAZ and WLZ associated with GWG.ResultsIn early infancy, compared with infants of women with adequate weight gain, those of women with excessive weight gains had higher WAZ, LAZ and WLZ. Excessive GWG ≥ 200% of the recommended amount was associated with faster rates of change in WAZ and LAZ and noticeably higher predicted mean WAZ and WLZ that persisted across the study period.ConclusionsGWG is associated with significant differences in offspring anthropometrics in early infancy that persisted to 3 years of age. More longitudinal studies that utilize maternal and paediatric body composition measures are necessary to understand the nature of this association.
Key Residues for Controlling Enantioselectivity of Halohydrin Dehalogenase from Arthrobacter sp. Strain AD2, Revealed by Structure-Guided Directed Evolution
Authors: Tang Lixia , Zhu Xuechen , Zheng Huayu , Jiang Rongxiang , Majerić Elenkov Maja 
Published: February 2012

ABSTRACT

Halohydrin dehalogenase from
Agrobacterium radiobacter
AD1 (HheC) is a valuable tool in the preparation of
R
enantiomers of epoxides and β-substituted alcohols. In contrast, the halohydrin dehalogenase from
Arthrobacter
sp. AD2 (HheA) shows a low
S
enantioselectivity toward most aromatic substrates. Here, three amino acids (V136, L141, and N178) located in the two neighboring active-site loops of HheA were proposed to be the key residues for controlling enantioselectivity. They were subjected to saturation mutagenesis aimed at evolving an
S
-selective enzyme. This led to the selection of two outstanding mutants (the V136Y/L141G and N178A mutants). The double mutant displayed an inverted enantioselectivity (from
S
enantioselectivity [

E
S

] = 1.7 to
R
enantioselectivity [

E
R

] = 13) toward 2-chloro-1-phenylethanol without compromising enzyme activity. Strikingly, the N178A mutant showed a large enantioselectivity improvement (

E
S

> 200) and a 5- to 6-fold-enhanced specific activity toward (
S
)-2-chloro-1-phenylethanol. Further analysis revealed that those mutations produced some interference for the binding of nonfavored enantiomers which could account for the observed enantioselectivities. Our work demonstrated that those three active-site residues are indeed crucial in modulating the enantioselectivity of HheA and that a semirational design strategy has great potential for rapid creation of novel industrial biocatalysts.
Pathogen Prevalence in Ticks Collected from the Vegetation and Livestock in Nigeria
Authors: Reye Anna L. , Arinola Olatunbosun G. , Hübschen Judith M. , Muller Claude P. 
Published: February 2012

ABSTRACT

Ticks are important disease vectors that can cause considerable economic losses by affecting animal health and productivity, especially in tropical and subtropical regions. In this study, we investigated the prevalence and diversity of bacterial and protozoan tick-borne pathogens in ticks collected from the vegetation and cattle in Nigeria by PCR. The infection rates of questing ticks were 3.1% for
Rickettsia
species, 0.1% for
Coxiella burnetii
and 0.4% for
Borrelia
species. Other pathogens, such as
Babesia
,
Theileria
,
Anaplasma
, and
Ehrlichia
species, were not detected in ticks from the vegetation. Feeding ticks collected from cattle displayed infection rates of 12.5% for
Rickettsia
species, 14% for
Coxiella burnetii
, 5.9% for
Anaplasma
species, 5.1% for
Ehrlichia
species, and 2.9% for
Theileria mutans. Babesia
and
Borrelia
species were not detected in ticks collected from cattle. Mixed infections were found only in feeding ticks and mainly
Rickettsia
species and
Coxiella burnetii
were involved. The diversity of tick-borne pathogens in Nigeria was higher in feeding than in questing ticks, suggesting that cattle serve as reservoirs for at least some of the pathogens studied, in particular
C. burnetii
. The total estimated herd infection rates of 20.6% for a
Rickettsia africae
-like species, 27% for
Coxiella burnetii
, and 8.5% for
Anaplasma marginale/centrale
suggest that these pathogens may have considerable implications for human and animal health.
Inactivation of Recombinant Bacteriophage Lambda by Use of Chemical Agents and UV Radiation
Authors: Clark Ewan M. , Wright Harry , Lennon Kelly-Anne , Craik Vicki A. , Clark Jason R. , March John B. 
Published: February 2012

ABSTRACT

Several approaches for the inactivation of bacteriophage lambda, including UV germicidal irradiation (UVGI) and the chemical agents Virkon-S, Chloros, Decon-90, and sodium hydroxide (NaOH), were compared. Virkon, NaOH, and UVGI caused a ≥7-log
10
reduction in phage titers. This study successfully describes several methods with potential for bacteriophage inactivation in industrial settings.
Pseudomonad Swarming Motility Is Restricted to a Narrow Range of High Matric Water Potentials
Authors: Dechesne Arnaud , Smets Barth F. 
Published: February 2012

ABSTRACT

Using a novel experimental system that allows control of the matric potential of an agar slab, we explored the hydration conditions under which swarming motility is possible. If there is recognition that this physical parameter is a key determinant of swarming, it is usually neither controlled nor measured rigorously but only manipulated through proxies, namely, the agar concentration and the drying time of “soft” agar plates (swarming plates). We contend that this not only obscures the biophysical mechanisms underlying swarming but also impedes a full assessment of its clinical and environmental significances. Our results indicate that swarming motility is restricted to a narrow range of high matric water potentials in the three pseudomonads tested (
Pseudomonas
sp. DSS73,
Pseudomonas syringae
B728a, and
Pseudomonas aeruginosa
PA14). The threshold below which no swarming was observed was about −0.45 kPa for the first and about −0.1 kPa for the latter two. Above the threshold, the expansion rate of DSS73 swarms increased exponentially with the matric potential. Mutants deficient in surfactant production were totally or partially unable to expand rapidly on the surface of the agar slab. Our results thus suggest that swarming motility in pseudomonads is restricted to (micro)sites where ambient humidity is very high (relative humidity of >99.99%). The spatiotemporal occurrence of such sites is limited in many types of terrestrial environments.
Persistence and Growth of the Fecal Indicator Bacteria Enterococci in Detritus and Natural Estuarine Plankton Communities
Authors: Mote Beth L. , Turner Jeffrey W. , Lipp Erin K. 
Published: February 2012

ABSTRACT

Enterococci are used to evaluate recreational-water quality and health risks in marine environments. In addition to their occurrence in feces of warm blooded animals, they are also common epiphytes. We investigated the contribution of plankton- or particle-associated enterococci in estuarine and coastal water. Seven water and size-fractionated plankton samples were collected monthly between April 2008 and January 2009 in the tidal reaches of the Skidaway River (Georgia, USA). Each size fraction, along with filtered (<30 μm) and bulk estuarine water, was processed according to U.S. Environmental Protection Agency method 1600. Presumptive enterococci were selected and species were identified using carbon substrate utilization patterns. The highest average densities occurred within the 30-, 63-, 105-, and 150-μm size fractions, which also represented the majority (>99%) of the particles within the sampled water. Particle-associated enterococci accounted for as little as 1% of enterococci in bulk water in April to as much as 95% in July.
Enterococcus faecalis
was the most commonly isolated species from both water and plankton and represented 31% (16/51) and 35% (6/17) of the identified
Enterococcus
species from water and plankton, respectively.
Enterococcus casseliflavus
represented 29% of the selected isolates from plankton and 16% from water. Both
E. faecalis
and
E. casseliflavus
were able to survive and grow in plankton suspensions significantly longer than in artificial seawater.
Enterococcus
spp. may be highly concentrated in plankton and associated particles, especially during summer and fall months. These findings could have implications for the effectiveness of enterococci as an indicator of coastal water quality, especially in particle-rich environments.
Two Novel Type II Restriction-Modification Systems Occupying Genomically Equivalent Locations on the Chromosomes of Listeria monocytogenes Strains
Authors: Lee Sangmi , Ward T. J. , Siletzky R. M. , Kathariou S. 
Published: February 2012

ABSTRACT

Listeria monocytogenes
is responsible for the potentially life-threatening food-borne disease listeriosis. One epidemic-associated clonal group of
L. monocytogenes
, epidemic clone I (ECI), harbors a Sau3AI-like restriction-modification (RM) system also present in the same genomic region in certain strains of other lineages. In this study, we identified and characterized two other, novel type II RM systems, LmoJ2 and LmoJ3, at this same locus. LmoJ2 and LmoJ3 appeared to recognize GCWGC (W = A or T) and GCNGC, respectively. Both RM systems consisted of genes with GC content below the genome average and were in the same genomic region in strains of different serotypes and lineages, suggesting site-specific horizontal gene transfer. Genomic DNA from the LmoJ2 and LmoJ3 strains grown at various temperatures (4 to 42°C) was resistant to digestion with restriction enzymes recognizing GCWGC or GCNGC, indicating that the methyltransferases were expressed under these conditions. Phages propagated in an LmoJ2-harboring strain exhibited moderately increased infectivity for this strain at 4 and 8°C but not at higher temperatures, while phages propagated in an LmoJ3 strain had dramatically increased infectivity for this strain at all temperatures. Among the sequenced
Listeria
phages, lytic phages possessed significantly fewer recognition sites for these RM systems than lysogenic phages, suggesting that in lytic phages sequence content evolved toward reduced susceptibility to such RM systems. The ability of LmoJ2 and LmoJ3 to protect against phages may affect the efficiency of phages as biocontrol agents for
L. monocytogenes
strains harboring these RM systems.