bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calcite and dolomite dissolution rates in the context of microbe–mineral surface interactions
Authors: DAVIS K. J. , NEALSON K. H. , LÜTTGE A. 
Published: May 2007

ABSTRACTAlthough microbes have been shown to alter the dissolution rate of carbonate minerals, a mechanistic understanding of the consequences of microbial surface colonization on carbonate dissolution has yet to be achieved. Here we report the use of vertical scanning interferometry (VSI) to study the effect of Shewanella oneidensis MR‐1 surface colonization on the dissolution rates of calcite (CaCO3) and dolomite (CaMg(CO3)2) through qualitative analysis of etch pit development and quantitative measurements of surface‐normal dissolution rates. By quantifying and comparing the significant processes occurring at the microbe–mineral interface, the dominant mechanism of mineral dissolution during surface colonization was determined. MR‐1 attachment under aerobic conditions was found to influence carbonate dissolution through two distinct mechanistic pathways: (1) inhibition of carbonate dissolution through interference with etch pit development and (2) excavation of carbonate material at the cell–mineral interface during irreversible attachment to the mineral surface. The relative importance of these two competing effects was found to vary with the solubility of the carbonate mineral studied. For the faster‐dissolving calcite substrates, inhibition of dissolution by attachment and subsequent extracellular polysaccharide (EPS) production was the dominant effect associated with MR‐1 surface colonization. This interference with etch pit development resulted in a 40–70% decrease in the surface normal dissolution rate relative to cell‐free controls, depending primarily on the concentration of cells in solution. However, in the case of the slower‐dissolving dolomite substrates, carbonate material displaced during the entrenchment of cells on the surface far outweighed the abiotic dissolution rate. Therefore, during the initial stages of surface colonization, dolomite dissolution rates were actually enhanced by MR‐1 attachment. This study demonstrates the dynamic and competitive relationship between microbial surface colonization and mineral dissolution that may be expected to occur in natural environments.
Dietary iron overload in the African and hepatocellular carcinoma
Authors: Kew Michael C. , Asare George A. 
Published: May 2007

AbstractDietary iron overload occurs commonly in parts of sub‐Saharan Africa. It results from the consumption of large volumes of traditional beer that is home‐brewed in iron pots or drums and consequently has a high iron content. The liver becomes iron overloaded and may develop portal fibrosis or, less often, cirrhosis. A genetic predisposition to the condition has been suggested, but no putative gene has yet been identified. Although originally believed not to cause hepatocellular carcinoma, recent case–control studies have shown African Blacks with dietary iron overload to be at increased risk for the tumour and a causal association has been confirmed in an animal model. The mechanisms of iron‐induced malignant transformation are yet to be fully characterised, but the close association between cirrhosis and hepatocellular carcinoma in patients with hereditary haemochromatosis and the lesser association in those with dietary iron overload, suggests that chronic necroinflammatory hepatic disease contributes to the malignant transformation. Increased hepatic iron may, however, also be directly carcinogenic. Probable mechanisms include the generation of reactive oxygen intermediates and the resultant chronic oxidative stress that damages hepatocytes and proteins, causes lipid peroxidation, and induces strand breaks, DNA unwinding, and mutations in tumour‐suppressor genes and critical DNA repair genes.
Planning for pandemic influenza: effect of a pandemic on the supply and demand for blood products in the United States
Authors: Zimrin Ann B. , Hess John R. 
Published: May 2007

BACKGROUND: Influenza causes episodic pandemics when viral antigens shift in ways that elude herd immunity. Avian influenza A H5N1, currently epizootic in bird populations in Asia and Europe, appears to have pandemic potential.STUDY DESIGN AND METHODS: The virology of influenza, the history of the 1918 pandemic, and the structure of the health care and the blood transfusion systems are briefly reviewed. Morbidity and mortality experience from the 1918 pandemic are projected onto the current health care structure to predict points of failure that are likely in a modern pandemic.RESULTS: Blood donor centers are likely to experience loss of donors, workers, and reliable transport of specimens to national testing laboratories and degradation of response times from national testing labs. Transfusion services are likely to experience critical losses of workers and of reagent red cells (RBCs) that will make their automated procedures unworkable. Loss of medical directors, supervisors, and lead technicians may make alternative procedures unworkable as well.CONCLUSIONS: Lower blood collection capacity and transfusion service support capability will reduce the availability of RBCs and especially of platelets. Plans for rationing medical care need to take the vulnerability of the blood transfusion system into account.
Randomized clinical trials in implant therapy: relationships among methodological, statistical, clinical, paratextual features and number of citations
Authors: Nieri Michele , Clauser Carlo , Franceschi Debora , Pagliaro Umberto , Saletta Daniele , Pini‐Prato Giovanpaolo 
Published: May 2007

AbstractObjectives: The aim of the present study was to investigate the relationships among reported methodological, statistical, clinical and paratextual variables of randomized clinical trials (RCTs) in implant therapy, and their influence on subsequent research.Materials and Methods: The material consisted of the RCTs in implant therapy published through the end of the year 2000. Methodological, statistical, clinical and paratextual features of the articles were assessed and recorded. The perceived clinical relevance was subjectively evaluated by an experienced clinician on anonymous abstracts. The impact on research was measured by the number of citations found in the Science Citation Index. A new statistical technique (Structural learning of Bayesian Networks) was used to assess the relationships among the considered variables.Results: Descriptive statistics revealed that the reported methodology and statistics of RCTs in implant therapy were defective. Follow‐up of the studies was generally short. The perceived clinical relevance appeared to be associated with the objectives of the studies and with the number of published images in the original articles. The impact on research was related to the nationality of the involved institutions and to the number of published images.Conclusions: RCTs in implant therapy (until 2000) show important methodological and statistical flaws and may not be appropriate for guiding clinicians in their practice. The methodological and statistical quality of the studies did not appear to affect their impact on practice and research. Bayesian Networks suggest new and unexpected relationships among the methodological, statistical, clinical and paratextual features of RCTs.
Early functional loading of sand‐blasted and acid‐etched (SLA) Straumann implants following immediate placement in maxillary extraction sockets. Clinical and radiographic result
Authors: Nordin Thomas , Graf Johan , Frykholm Anders , Helldén Leif 
Published: May 2007

AbstractObjectives: To present the clinical and radiographic outcome of early loading of implants inserted into fresh extraction sockets and to present a treatment protocol for early loading of the implants by ‘passively fitting’ abutment‐free permanent fixed complete dentures (implant FCDs).Material and methods: The study included 19 dentate patients treatment planned for extraction of all remaining maxillary teeth. In all, 116 Straumann‐implants with sandblasted, large grit and acid etched (SLA) surface were placed: 77 (66%) inserted in fresh extraction sockets and 39 (34%) in healed bone. At least six implants were placed in each maxilla. One hundred and ten implants were loaded by permanent FCDs within 10 days after placements and six after 14 days. The patients were reexamined clinically and radiographically after 2–3 years of clinical function. All FCDs were removed for control of implant stability and evaluation of the peri‐implant status.Results: Owing to framework fracture, two implants were lost, corresponding to a failure rate of 2%. The radiographic measurements after 2–3 years did not reveal any difference in bone height mesial and distal of the implants placed in extraction sockets vs. in healed bone. This was interpreted as a bone gain around the implants placed in extraction sockets and a slight bone loss around the implants placed in healed bone.Conclusion: Early functional loading of SLA‐surfaced implants following immediate placement in maxillary extraction sockets by rigid and passively fitting permanent implant FCDs is a reliable treatment alternative.
Human tissue kallikrein expression in the stratum corneum and serum of atopic dermatitis patients
Authors: Komatsu Nahoko , Saijoh Kiyofumi , Kuk Cynthia , Liu Amber C. , Khan Saba , Shirasaki Fumiaki , Takehara Kazuhiko , Diamandis Eleftherios P. 
Published: May 2007

Abstract:  Human tissue kallikreins are a family of 15 trypsin‐ or chymotrypsin‐like secreted serine proteases (KLK1–KLK15). Many KLKs have been identified in normal stratum corneum (SC) and sweat, and are candidate desquamation‐related proteases.We report quantification by enzyme‐linked immunosorbent assay (ELISA) of KLK5, KLK6, KLK7, KLK8, KLK10, KLK11, KLK13 and KLK14 in the SC and serum of atopic dermatitis (AD) patients by ELISA, and examine their variation with clinical phenotype, correlation with blood levels of eosinophils, lactate dehydrogenase (LDH) and immunoglobulin E. The overall SC serine protease activities were also measured.In the SC of AD, all KLKs, except KLK11, were significantly elevated. The elevation of chymotrypsin‐like KLK7 was predominant, compared with trypsin‐like KLKs. The SC overall plasmin‐ and furin‐like activities were significantly elevated, while trypsin‐ and chymotrypsin‐like activities did not differ significantly. In the serum of AD patients, KLK8 was significantly elevated and KLK5 and KLK11 were significantly decreased. However, their serum levels were not modified by corticosteroid topical agents. The alterations of KLK levels in the SC of AD were more pronounced than those in the serum. KLK7 in the serum was significantly correlated with eosinophil counts in the blood of AD patients, while KLK5, KLK8 and KLK11 were significantly correlated with LDH in the serum.In conclusion, we report abnormal kallikrein levels in the SC and the serum of AD patients. KLKs might be involved in skin manifestation and/or focal/systemic inflammatory reactions in AD. Our data may contribute to a better understanding of the pathogenesis of AD.
Microarray analysis of nicotine‐induced changes in gene expression in a macrophage‐like human cell line
Authors: Koshi R. , Sugano N. , Orii H. , Fukuda T. , Ito K. 
Published: May 2007

Background and Objective:  Cigarette smoking has been suggested as a risk factor for periodontitis. Thousands of components are present in cigarette smoke, including nicotine, which may play an important role in the observed effects of smoking on cell metabolism. However, the mechanisms underlying these effects are unclear. Using DNA microarrays, we monitored differentially expressed genes, responsive to nicotine, in a macrophage‐like human cell line.Material and Methods:  Human U937 cells were treated for 1 h, with or without 1.0 µg/ml of nicotine. For differentiation, cultures were incubated with 10 nm phorbol myristate acetate for 48 h. Analysis of gene expression was performed using a DNA microarray of 8500 genes.Results:  The expression of 4914 genes was detected. Screening was carried out on those genes whose expression in three separate experiments showed an average change of twofold or greater, and 118 up‐regulated genes and 97 down‐regulated genes were identified. Among these were genes related to inflammation and other immune responses, such as phospholipase A2 and interferon. Consistent with the array findings, we found similar changes in mRNA expression after analysis using the real‐time polymerase chain reaction.Conclusion:  The results suggest that nicotine causes excess inflammation and disturbs host defense mechanisms against pathogens.
Genetic factors associated with skin cancer in renal transplant patients
Authors: Laing Mary Elizabeth , Kay Elaine , Conlon Peter , Murphy Gillian M. 
Published: May 2007

Background: Non‐melanoma skin cancer represents a significant cause of morbidity and mortality among renal transplant recipients. Established risk factors that increase susceptibility to skin cancer after transplantation include skin type, sun exposure and level of immunosuppression.Methods: A comprehensive literature review was carried out to discuss relevant genetic polymorphism for the development of skin cancer in organ transplant recipients. These include genetic polymorphisms in glutathione S‐transferase, interleukin‐10, retinoblastoma and p53 genes. We also discuss genetic polymorphisms in the folate pathway, melanocortin 1 receptor and vitamin D receptor recently discovered in our group.Results: No single factor is causative in cutaneous carcinogenesis in transplant recipients. Interactions of some of the above mechanisms with known environmental factors lead to increased risk.Conclusion: Polymorphisms in methylenetetrahydrofolate reductase are potentially correctable with folic acid supplementation; however, further evaluation is required in adequately powered prospective clinical trials. Avoidance of known oncogenic environmental factors and genetic risk evaluation may improve outcomes in transplant patients.
Topical application of plant extracts containing xanthine derivatives can prevent UV‐induced wrinkle formation in hairless mice
Authors: Mitani Hiroaki , Ryu Akemi , Suzuki Tadashi , Yamashita Mika , Arakane Kumi , Koide Chiharu 
Published: May 2007

Background: Plants are the source of important products with nutritional and therapeutic value. Topical or oral administration of some plant extracts has been shown to reduce photodamage. Cacao bean and cola nut are popular edible plants that contain polyphenols and xanthine derivatives. These plant extracts possess protective effects against UV‐induced erythema when taken orally, and an H2O2‐scavenging effect.Methods: Plant extracts containing xanthine derivatives and three xanthine derivatives were topically applied to the dorsal skin of hairless mice, and the mice were exposed to a resemblance of solar ultraviolet irradiation at a dose of 13.0 J/cm2 (UVA) for 15 weeks, five times a week on weekdays. After the final irradiation, histological, and analytical studies were performed.Results: Topical application of plant extracts (cacao beans, cola nuts) and caffeine, theobromine, and theophylline markedly prevented photodamage including wrinkle formation and histological alterations. A significant increase in total hydroxyproline content caused by UV irradiation was observed. In contrast, topical application of plant extracts and xanthine derivatives reduced total hydroxyproline and pepsin‐resistant hydroxyproline content in comparison with that of the control (vehicle, UV‐irradiation group). Moreover, naphthol AS‐D chloroacetate esterase staining and diaminobenzidine staining suggested that leukocytes including neutrophils increased in the UV‐exposed skin. In contrast, weak staining was observed in skin treated with xanthine derivatives.Conclusion: Topical application of plant extracts and xanthine derivatives suppressed wrinkle formation, dermal connective alteration, and collagen accumulation. It is suggested that xanthine derivatives prevented neutrophil infiltration caused by UV‐irradiation.
Single nucleotide polymorphisms in mannan‐binding lectins and ficolins in various strains of mice
Authors: Phaneuf L. R. , Lillie B. N. , Hayes M. A. , Turner P. V. 
Published: May 2007

SummaryMannan‐binding lectin (MBL) and ficolin are collagenous lectins produced primarily by the liver and are involved in innate resistance to microbial pathogens. Mice have two MBL genes (Mbl1 and Mbl2) that encode MBL‐A and MBL‐C, respectively. Similarly, the murine Fcna and Fcnb genes encode ficolin‐A and ficolin‐B. Several single nucleotide polymorphisms (SNP) in the human MBL2 gene are responsible for various innate immune dysfunctions due to abnormal structure or expression of human MBL‐C. In these studies, we identified SNPs in the expressed collagenous lectin genes Mbl1, Mbl2, Fcna, and Fcnb in 10 strains of mice designated high priority Group A strains by the Mouse Phenome Project (129S1/SvImJ, A/J, BALB/cByJ, C3H/HeJ, C57BL/6 J, DBA/2 J, FVB/NJ, SJL/J, CAST/EiJ and SPRET/EiJ) by sequencing gene exons by reverse transcription‐polymerase chain reaction (RT‐PCR). Sequence comparisons identified a total of 15 structural SNPs in Mbl1 in two strains, 27 SNPs in Mbl2 in five strains, and 19 and 15 SNPs in Fcna and Fcnb, respectively, in two strains. Two non‐synonymous SNPs were identified in the collagen‐like domain of mouse Fcnb that are similar to the coding polymorphisms in the collagen‐like domain of human MBL2. Most of the non‐synonymous SNPs identified in Mbl1 and Mbl2 occurred in the carbohydrate‐recognition domains (CRDs), and some resulted in altered residues close to known ligand binding sites. Similarly, most non‐synonymous SNPs of Fcna and Fcnb were identified in the fibrinogen‐like CRD. The miscoding SNPs found in the CRD regions of mouse Mbl1, Mbl2, Fcna and Fcnb may be associated with strain differences in glycan binding avidity and disposition of microbial or host ligands. Furthermore, the non‐synonymous mutations in the collagen‐like domain of Fcnb may alter the structure of the mature ficolin‐B protein leading to functional deficiencies. These differences may be important in the pathogenesis of susceptibility differences between inbred strains to various infectious microorganisms.
A method for the direct determination of the surface gravities of transiting extrasolar planets
Authors: Southworth John , Wheatley Peter J. , Sams Giles 
Published: May 2007

Abstract
We show that the surface gravity of a transiting extrasolar planet can be calculated from only the spectroscopic orbit of its parent star and the analysis of its transit light curve. This does not require additional constraints, such as are often inferred from theoretical stellar models or model atmospheres. The surface gravity of the planet can therefore be measured precisely and from only directly observable quantities. We outline the method and apply it to the case of the first known transiting extrasolar planet, HD 209458b. We find a surface gravity of gp= 9.28 ± 0.15 m s−2, which is an order of magnitude more precise than the best available measurements of its mass, radius and density. This confirms that the planet has a much lower surface gravity than that predicted by published theoretical models of gas giant planets. We apply our method to all 14 known transiting extrasolar planets and find a significant correlation between surface gravity and orbital period, which is related to the known correlation between mass and period. This correlation may be the underlying effect as surface gravity is a fundamental parameter in the evaporation of planetary atmospheres.
PHYSICOCHEMICAL AND SENSORY PROPERTIES OF TOFU PREPARED WITH HEAT‐TREATED SOYBEANS
Authors: YOON HYE HYUN , KIM MEERA 
Published: May 2007

ABSTRACT The sensory characteristics of tofu made from soybeans (var. TaeKwang) heat treated at 60C for 60, 120 and 180 min were investigated to determine the effects of heat shock on the texture and flavor of tofu, which play an important role in consumer preference. Hardness and chewiness increased with heat treatment, reaching maxima at 120 min, while cohesiveness decreased significantly with heat treatment in the 120 min sample. Sensory evaluation showed that the smoothness and homogeneity of the surface of the tofu increased with heat treatment from those of the control. Grassy aroma, which is one of the main undesirable flavors of tofu, was decreased by the heat treatment. Firmness and elasticity both had a maximum value of 8.4 by the 15‐cm line‐scale evaluation in the 120 min treated samples, showing the practical possibility of using mild heat treatment to produce firm and elastic tofu. Increases in the 7S globulin due to heat treatment are thought to be responsible for the textural changes observed. PRACTICAL APPLICATIONSTexture and flavor are major factors in determining the quality of tofu. Tofu has become popular as a healthy food and its consumption is increasing, hence the necessity of producing tofu with various kinds of texture. We found that heat treatment on soybean used in tofu preparation can be one of the methods to control the texture of tofu. The grassy flavor of soy products is the limiting factor that seriously affects their consumption. According to our sensory evaluation, the grassy aroma was decreased significantly by heat treatment, showing that controlled heat treatment has a positive effect on the overall quality of tofu. This study suggests that heat treatment of soybeans can be applied to produce tofu with less grassy flavor and firmer texture.
EFFECTS OF BIOPOLYMER ADDITION ON THE DYNAMIC RHEOLOGY AND MICROSTRUCTURE OF RENNETED SKIM MILK SYSTEMS
Authors: TAN Y.L. , YE A. , SINGH H. , HEMAR Y. 
Published: May 2007

ABSTRACT The influence of κ‐carrageenan, xanthan gum, guar gum, high‐methoxyl (HM) pectin and gelatin addition on the rheological and microstructural properties of rennet‐induced skim milk gels was investigated using a stress‐controlled rheometer, syneresis measurement and confocal laser scanning microscopy. The elasticity, aggregation and gelation times of renneted skim milk decreased with increasing amounts of added κ‐carrageenan, xanthan gum and guar gum, whereas they increased with increasing amounts of added HM pectin and gelatin. Syneresis of the rennet‐induced skim milk gels decreased when HM pectin and gelatin were added, but increased when κ‐carrageenan, xanthan gum and guar gum were added. The changes in the viscoelastic properties and syneresis of renneted skim milk were attributed to the change in the microstructure of the rennet‐induced skim milk gel after the addition of the biopolymers. The branched protein network structure of the rennet‐induced skim milk gel could not be formed in the presence of high concentrations of xanthan gum, κ‐carrageenan and guar gum because of the formation of large protein aggregates or an open network structure with large voids. PRACTICAL APPLICATIONSThere has been a steady growth in cheese sales over the last decade, mainly because of the increased use of cheese as an ingredient in a number of prepared foods, in which the cheese is used to add taste, texture and nutritional quality. However, because of the high cost associated with natural cheese production and storage, as well as its functional variability, the dairy industry has been aggressively seeking alternatives. Polysaccharides are used extensively in a variety of commercial dairy products as stabilizers and thickening or gelling agents. Furthermore, the use of polysaccharides is an attractive route to cost reduction in dairy products. However, as demonstrated in the present study, under certain conditions of biopolymer concentration, e.g., the use of some polysaccharides in cheese making can result in a decrease in the gel strength and whey holding ability of the cheese. Thus, avoiding the use of polysaccharides, which are known to phase separate when mixed with milk proteins, is highly recommended.