bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isomalto oligosaccharide sulfate inhibits tumor growth and metastasis of hepatocellular carcinoma in nude mice
Authors: Xiao Chun-Li , Tao Zhong-Hua , Guo Lin , Li Wei-Wei , Wan Jin-Liang , Sun Hui-Chuan , Wang Lu , Tang Zhao-You , Fan Jia , Wu Wei-Zhong 
Published: April 2011

Abstract

Background
Hepatocellular carcinoma (HCC) usually has a dismal prognosis because of its limited response to current pharmacotherapy and high metastatic rate. Sulfated oligosaccharide has been confirmed as having potent antitumor activities against solid tumors. Here, we explored the preclinical effects and molecular mechanisms of isomalto oligosaccharide sulfate (IMOS), another novel sulfated oligosaccharide, in HCC cell lines and a xenograft model.

Methods
The effects of IMOS on HCC proliferation, apoptosis, adhesion, migration, and invasiveness in vitro were assessed by cell counting, flow cytometry, adhesion, wound healing, and transwell assays, respectively. The roles of IMOS on HCC growth and metastasis in xenograft models were evaluated by tumor volumes and fluorescent signals. Total and phosphorylated protein levels of AKT, ERK, and JNK as well as total levels of c-MET were detected by Western blotting. IMOS-regulated genes were screened by quantitative reverse-transcription PCR (qRT-PCR) array in HCCLM3-red fluorescent protein (RFP) xenograft tissues and then confirmed by qRT-PCR in HepG2 and Hep3B cells.

Results
IMOS markedly inhibited cell proliferation and induced cell apoptosis of HCCLM3, HepG2, and Bel-7402 cells and also significantly suppressed cell adhesion, migration, and invasion of HCCLM3 in vitro. At doses of 60 and 90 mg/kg/d, IMOS displayed robust inhibitory effects on HCC growth and metastasis without obvious side effects in vivo. The levels of pERK, tERK, and pJNK as well as c-MET were significantly down-regulated after treatment with 16 mg/mL IMOS. No obvious changes were found in the levels of pAkt, tAkt, and tJNK. Ten differentially expressed genes were screened from HCCLM3-RFP xenograft tissues after treatment with IMOS at a dose of 90 mg/kg/d. Similar gene expression profiles were confirmed in HepG2 and Hep3B cells after treatment with 16 mg/mL IMOS.

Conclusions
IMOS is a potential anti-HCC candidate through inhibition of ERK and JNK signaling independent of p53 and worth studying further in patients with HCC, especially at advanced stages.
Factors affecting staff morale on inpatient mental health wards in England: a qualitative investigation
Authors: Totman Jonathan , Hundt Gillian Lewando , Wearn Elizabeth , Paul Moli , Johnson Sonia 
Published: April 2011

Abstract

Background
Good morale among staff on inpatient psychiatric wards is an important requirement for the maintenance of strong therapeutic alliances and positive patient experiences, and for the successful implementation of initiatives to improve care. More understanding is needed of mechanisms underlying good and poor morale.

Method
We conducted individual and group interviews with staff of a full range of disciplines and levels of seniority on seven NHS in-patient wards of varying types in England.

Results
Inpatient staff feel sustained in their potentially stressful roles by mutual loyalty and trust within cohesive ward teams. Clear roles, supportive ward managers and well designed organisational procedures and structures maintain good morale. Perceived threats to good morale include staffing levels that are insufficient for staff to feel safe and able to spend time with patients, the high risk of violence, and lack of voice in the wider organisation.

Conclusions
Increasing employee voice, designing jobs so as to maximise autonomy within clear and well-structured operational protocols, promoting greater staff-patient contact and improving responses to violence may contribute more to inpatient staff morale than formal support mechanisms.
Establishment of a murine epidermal cell line suitable for in vitro and in vivo skin modelling
Authors: Segrelles Carmen , Holguín Almudena , Hernández Pilar , Ariza José M , Paramio Jesús M , Lorz Corina 
Published: April 2011

Abstract

Background
Skin diseases are a major health problem. Some of the most severe conditions involve genetic disorders, including cancer. Several of these human diseases have been modelled in genetically modified mice, thus becoming a highly valuable preclinical tool for the treatment of these pathologies. However, development of three-dimensional models of skin using keratinocytes from normal and/or genetically modified mice has been hindered by the difficulty to subculture murine epidermal keratinocytes.

Methods
We have generated a murine epidermal cell line by serially passaging keratinocytes isolated from the back skin of adult mice. We have termed this cell line COCA. Cell culture is done in fully defined media and does not require feeder cells or any other coating methods.

Results
COCA retained its capacity to differentiate and stratify in response to increased calcium concentration in the cell culture medium for more than 75 passages. These cells, including late passage, can form epidermis-like structures in three-dimensional in vitro models with a well-preserved pattern of proliferation and differentiation. Furthermore, these cells form epidermis in grafting assays in vivo, and do not develop tumorigenic ability.

Conclusions
We propose that COCA constitutes a good experimental system for in vitro and in vivo skin modelling. Also, cell lines from genetically modified mice of interest in skin biology could be established using the method we have developed. COCA keratinocytes would be a suitable control, within a similar background, when studying the biological implications of these alterations.
Exploiting the high-resolution crystal structure of Staphylococcus aureus MenH to gain insight into enzyme activity
Authors: Dawson Alice , Fyfe Paul K , Gillet Florian , Hunter William N 
Published: April 2011

Abstract

Background
MenH (2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase) is a key enzyme in the biosynthesis of menaquinone, catalyzing an unusual 2,5-elimination of pyruvate from 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexadiene-1-carboxylate.

Results
The crystal structure of Staphylococcus aureus MenH has been determined at 2 Å resolution. In the absence of a complex to inform on aspects of specificity a model of the enzyme-substrate complex has been used in conjunction with previously published kinetic analyses, site-directed mutagenesis studies and comparisons with orthologues to investigate the structure and reactivity of MenH.

Conclusions
The overall basic active site displays pronounced hydrophobic character on one side and these properties complement those of the substrate. A complex network of hydrogen bonds involving well-ordered water molecules serves to position key residues participating in the recognition of substrate and subsequent catalysis. We propose a proton shuttle mechanism, reliant on a catalytic triad consisting of Ser89, Asp216 and His243. The reaction is initiated by proton abstraction from the substrate by an activated Ser89. The propensity to form a conjugated system provides the driving force for pyruvate elimination. During the elimination, a methylene group is converted to a methyl and we judge it likely that His243 provides a proton, previously acquired from Ser89 for that reduction. A conformational change of the protonated His243 may be encouraged by the presence of an anionic intermediate in the active site.
Suppression of low-density lipoprotein oxidation, vascular smooth muscle cell proliferation and migration by a herbal extract of Radix Astragali, Radix Codonopsis and Cortex Lycii
Authors: Chan Judy Y , Koon Johnny C , Leung Ping-Chung , Che Chun-Tao , Fung Kwok-Pui 
Published: April 2011

Abstract

Background
Atherosclerosis is a major cause of death in developed world. Atherosclerosis is characterized by low-density lipoprotein deposition in the arterial wall which ultimately begets the formation of lesions. Rupture of lesions finally leads to clinical events such as heart attack and stroke. Atherosclerosis is a complication associated with diabetes. In patients with diabetes, the risk of atherosclerosis is three to five folds greater than in non-diabetics. Our previous study showed that a herbal extract of Radix Astragali, Radix Codonopsis and Cortex Lycii, namely SR10, could improve glucose homeostasis both in vitro and in vivo. In this study, we want to further investigate the efficacy of SR10 in treating atherosclerosis.

Method
The inhibitory effect of SR10 on low-density lipoprotein oxidation was investigated using free radical-induced erythrocyte hemolysis model and copper ion-induced low-density lipoprotein oxidation model. Since vascular smooth muscle cell proliferation and migration are important processes in atherogenesis, we also examined the effect of SR10 in inhibiting these events.

Results
Our results showed that SR10 inhibited erythrocyte hemolysis with IC50 value at 0.25 mg/ml and significantly prolonged low-density lipoprotein oxidation in vitro. SR10 attenuated platelet derived growth factor-BB-induced vascular smooth muscle cell proliferation by promoting cell cycle arrest at G0/G1 phase as well as inhibiting vascular smooth muscle cell migration.

Conclusion
The potential application of SR10 in treating atherosclerosis has been implied in this study. Animal model will be needed to further verify the efficacy of SR10 in future.
Evaluation of the Pichia pastoris expression system for the production of GPCRs for structural analysis
Authors: Asada Hidetsugu , Uemura Tomoko , Yurugi-Kobayashi Takami , Shiroishi Mitsunori , Shimamura Tatsuro , Tsujimoto Hirokazu , Ito Keisuke , Sugawara Taishi , Nakane Takanori , Nomura Norimichi , Murata Takeshi , Haga Tatsuya , Iwata So , Kobayashi Takuya 
Published: April 2011

Abstract

Background
Various protein expression systems, such as Escherichia coli (E. coli), Saccharomyces cerevisiae (S. cerevisiae), Pichia pastoris (P. pastoris), insect cells and mammalian cell lines, have been developed for the synthesis of G protein-coupled receptors (GPCRs) for structural studies. Recently, the crystal structures of four recombinant human GPCRs, namely β2 adrenergic receptor, adenosine A2a receptor, CXCR4 and dopamine D3 receptor, were successfully determined using an insect cell expression system. GPCRs expressed in insect cells are believed to undergo mammalian-like posttranscriptional modifications and have similar functional properties than in mammals. Crystal structures of GPCRs have not yet been solved using yeast expression systems. In the present study, P. pastoris and insect cell expression systems for the human muscarinic acetylcholine receptor M2 subtype (CHRM2) were developed and the quantity and quality of CHRM2 synthesized by both expression systems were compared for the application in structural studies.

Results
The ideal conditions for the expression of CHRM2 in P. pastoris were 60 hr at 20°C in a buffer of pH 7.0. The specific activity of the expressed CHRM2 was 28.9 pmol/mg of membrane protein as determined by binding assays using [3H]-quinuclidinyl benzilate (QNB). Although the specific activity of the protein produced by P. pastoris was lower than that of Sf9 insect cells, CHRM2 yield in P. pastoris was 2-fold higher than in Sf9 insect cells because P. pastoris was cultured at high cell density. The dissociation constant (Kd) for QNB in P. pastoris was 101.14 ± 15.07 pM, which was similar to that in Sf9 insect cells (86.23 ± 8.57 pM). There were no differences in the binding affinity of CHRM2 for QNB between P. pastoris and Sf9 insect cells.

Conclusion
Compared to insect cells, P. pastoris is easier to handle, can be grown at lower cost, and can be expressed quicker at a large scale. Yeast, P. pastoris, and insect cells are all effective expression systems for GPCRs. The results of the present study strongly suggested that protein expression in P. pastoris can be applied to the structural and biochemical studies of GPCRs.
Revealing the beneficial effect of protease supplementation to high gravity beer fermentations using "-omics" techniques
Authors: Piddocke Maya P , Fazio Alessandro , Vongsangnak Wanwipa , Wong Man L , Heldt-Hansen Hans P , Workman Chris , Nielsen Jens , Olsson Lisbeth 
Published: April 2011

Abstract

Background
Addition of sugar syrups to the basic wort is a popular technique to achieve higher gravity in beer fermentations, but it results in dilution of the free amino nitrogen (FAN) content in the medium. The multicomponent protease enzyme Flavourzyme has beneficial effect on the brewer's yeast fermentation performance during high gravity fermentations as it increases the initial FAN value and results in higher FAN uptake, higher specific growth rate, higher ethanol yield and improved flavour profile.

Results
In the present study, transcriptome and metabolome analysis were used to elucidate the effect on the addition of the multicomponent protease enzyme Flavourzyme and its influence on the metabolism of the brewer's yeast strain Weihenstephan 34/70. The study underlines the importance of sufficient nitrogen availability during the course of beer fermentation. The applied metabolome and transcriptome analysis allowed mapping the effect of the wort sugar composition on the nitrogen uptake.

Conclusion
Both the transcriptome and the metabolome analysis revealed that there is a significantly higher impact of protease addition for maltose syrup supplemented fermentations, while addition of glucose syrup to increase the gravity in the wort resulted in increased glucose repression that lead to inhibition of amino acid uptake and hereby inhibited the effect of the protease addition.
ABO blood group and the risk of placental malaria in sub-Saharan Africa
Authors: Adegnika Ayola A , Luty Adrian JF , Grobusch Martin P , Ramharter Michael , Yazdanbakhsh Maria , Kremsner Peter G , Schwarz Norbert G 
Published: April 2011

Abstract

Background
In malarious areas of the world, a higher proportion of the population has blood group O than in non-malarious areas. This is probably due to a survival advantage conferred either by an attenuating effect on the course of or reduction in the risk of infection by plasmodial parasites. Here, the association between ABO blood group and incidence of placental malaria was assessed in order to determine the possible influence of the former on the latter.

Methods
Data from a study in Lambaréné, Gabon, and data from three previously published reports of studies in The Gambia, Malawi and Sudan, were compiled and compared. ABO blood groups were cross-tabulated with placental malaria stratified by parity. Odds ratios (OR), stratified by parity, were calculated for the outcome, placental parasitaemia, and compared between blood group O vs. non-O mothers in all four studies. Random effects meta-analysis of data from individual studies from areas with perennial hyper/holoendemic transmission was performed.

Results
In Gabon, the odds ratio (OR) for active placental parasitaemia in mothers with group O was 0.3 (95% CI 0.05-1.8) for primiparae and 0.7 (95% CI 0.3-1.8) for multiparae. The OR for primiparae in the published study from The Gambia was 3.0 (95% CI 1.2-7.3) and, in Malawi, 2.2 (95% CI 1.1-4.3). In the Sudanese study, no OR for primiparae could be calculated. The OR for placental parasitaemia in group O multiparae was 0.8 (95% CI 0.3-1.7) in the Gambia, 0.6 (95% CI 0.4-1.0) in Malawi and 0.4 (95% CI 0.1-1.8) in Sudan. Combining data from the three studies conducted in hyper-/holo-endemic settings (Gambia, Malawi, Gabon) the OR for placental malaria in blood group O multiparae was 0.65 (95% CI 0.44-0.96) and for primiparae 1.70 (95% CI 0.67-4.33).

Conclusion
Studies conducted in The Gambia and Malawi suggest that blood group O confers a higher risk of active placental infection in primiparae, but a significantly lower risk in multiparae. These findings were not confirmed by the study from Gabon, in which statistically non-significant trends for reduced risk of placental parasitaemia in those with blood group O, regardless of parity, were observed.
Molecular epidemiology of Plasmodium vivax anti-folate resistance in India
Authors: Prajapati Surendra K , Joshi Hema , Dev Vas , Dua Virendra K 
Published: April 2011

Abstract

Background
Sulphadoxine and pyrimethamine are anti-folate drugs that show synergistic anti-malarial effect. Point mutations in dihydrofolate reductase (dhfr) and dihydropteorate synthatase (dhps) cause anti-folate drug resistance phenotype in human malaria parasites. This study presents pattern of point mutations in dhfr/dhps genes among Indian sub-continent.

Methods
Microscopically diagnosed one hundred Plasmodium vivax field isolates were collected from five widely separated geographical regions of India. Dhfr and dhps genes were PCR amplified and sequenced. Previously published mutations data were collected and analyzed using Chi square test to identify geographical cluster of mutant/wild type genotypes.

Results
Sequence analysis revealed single (S58R), double (S58R/S117N) and quadruple (F57L/S58R/T61M/S117T/) point mutations at dhfr and single (A383G) to double (A383G/A553G) mutations at dhps in P. vivax field isolates. In addition, three new mutations were also observed at dhfr. Both, dhfr and dhps genes revealed tandem repeat variations in field isolates. Dhps revealed very low mutation frequency (14.0%) compared to dhfr (50.70%). Comparative analysis revealed a progressive increase in frequency of quadruple mutant dhfr genotype (p < 0.001) within five years in north-eastern state (Kamrup, Assam). Frequency of dhfr genotypes revealed three distinct geographical clusters of wild (northern India), double mutant (southern India), and quadruple mutant (north-eastern and island regions of India) on the Indian sub-continent.

Conclusion
Study suggests that SP may be susceptible to P. vivax in India, except Andaman and north-eastern state. The distinction of geographical regions with sensitive and resistant parasite phenotypes would be highly useful for designing and administering national anti-malarial drug policy.
A practical guide to bioelectrical impedance analysis using the example of chronic obstructive pulmonary disease
Authors: Walter-Kroker Anja , Kroker Axel , Mattiucci-Guehlke Muriel , Glaab Thomas 
Published: April 2011

Abstract
Bioelectrical impedance analysis (BIA) is a simple, inexpensive, quick and non-invasive technique for measuring body composition. The clinical benefit of BIA can be further enhanced by combining it with bioelectrical impedance vector analysis (BIVA). However, there is a substantial lack of information on the practical aspects of BIA/BIVA for those primarily interested in learning how to use and interpret this method in practice. The purpose of this article is to provide some guidance on the use of BIA/BIVA with special attention to practical considerations.
This report reflects the authors' practical experience with the use of single-frequency BIA in combination with BIVA, particularly in COPD patients. First, the method and principles of BIA/BIVA are briefly described. Then, a practice-oriented approach to the interpretation and analysis of characteristic examples of altered nutritional and fluid status as seen with BIA/BIVA in COPD patients (e.g. malnutrition in obese and underweight patients with COPD, water retention) is presented.
As our examples show BIA/BIVA is an attractive and easy-to-learn tool for quick nutritional assessment and is therefore of great clinical benefit in daily practice.
Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan
Authors: Li Shi , Batterman Stuart , Wasilevich Elizabeth , Elasaad Huda , Wahl Robert , Mukherjee Bhramar 
Published: April 2011

Abstract

Background
The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases.

Method
This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression.

Results
Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model.

Conclusions
There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based matched case-control study.
Role of bile salt in regulating Mcl-1 phosphorylation and chemoresistance in hepatocellular carcinoma cells
Authors: Liao Mingmei , Zhao Jinfeng , Wang Ton , Duan Jinghua , Zhang Yangde , Deng Xingming 
Published: April 2011

Abstract

Background
Glycochenodeoxycholate (GCDA) is one of the major human bile salts. Bile salts stimulate cell survival and proliferation through the mitogen-activated protein kinase, but the downstream signaling mechanism(s) remains enigmatic. Mcl-1 is an antiapoptotic molecule of the Bcl2 family that is extensively overexpressed in tumor tissues of patients with hepatocellular carcinoma (HCC).

Results
Here we found that exposure of HepG2 cells to GCDA results in activation of ERK1 and ERK2 and phosphorylation of Mcl-1 in a PD98059 (MEK inhibitor)-sensitive manner. GCDA stimulates Mcl-1 phosphorylation in cells expressing WT but not T163A Mcl-1 mutant, indicating that GCDA-induced Mcl-1 phosphorylation occurs exclusively at the T163 site in its PEST region. GCDA-induced Mcl-1 phosphorylation at T163 enhances the half-life of Mcl-1. Treatment of HepG2 cells with GCDA facilitates Mcl-1 dissociation from Mule (a physiological Mcl-1 ubiquitin E3 ligase). Specific depletion of Mcl-1 from HepG2 cells by RNA interference increases sensitivity of HepG2 cells to chemotherapeutic drugs (i.e. cisplatin and irinotecan). In addition to activation of the ERK/Mcl-1 survival pathway, GCDA can also induce dose-dependent apurinic/apyrimidinic (AP) sites of DNA lesions, which may partially neutralize its survival activity.

Conclusion
Our findings suggest that bile salt may function as a survival agonist and/or potential carcinogen in the development of HCC. Molecular approaches that inactivate Mcl-1 by blocking its T163 phosphorylation may represent new strategies for treatment of HCC.