bluuebunny/crossref_metadata_2025_split huggingface dataset:
The blood–CSF barrier explained: when development is not immaturity
Authors: Johansson Pia A. , Dziegielewska Katarzyna M. , Liddelow Shane A. , Saunders Norman R. 
Published: February 2008

AbstractIt is often suggested that during development the brain barriers are immature. This argument stems from teleological interpretations and experimental observations of the high protein concentrations in fetal cerebrospinal fluid (CSF) and decreases in apparent permeability of passive markers during development. We argue that the developmental blood–CSF barrier restricts the passage of lipid‐insoluble molecules by the same mechanism as in the adult (tight junctions) rendering the paracellular pathway an unlikely route of entry. Instead, we suggest that both protein and passive markers are transferred across the epithelium through a transcellular route. We propose that changes in volume of distribution can largely explain the decrease in apparent permeability for passive markers and that developmentally regulated cellular transfer explains changes in CSF protein concentrations. The blood–CSF tight junctions are functionally mature from very early in development, and it appears that transfer from blood into embryonic brain occurs predominately via CSF rather than the vasculature. BioEssays 30:237–248, 2008. © 2008 Wiley Periodicals, Inc.
Whole genome amplification using single‐primer PCR
Authors: Lao Kaiqin , Xu Nan Lan , Straus Neil A. 
Published: February 2008

AbstractComprehensive genomic molecular analyses require relatively large DNA amounts that are often not available from forensic, clinical and other crucial biological samples. Numerous methods to amplify the whole genome have been proposed for cancer, forensic and taxonomic research. Unfortunately, when using truly random primers for the initial priming step, all of these procedures suffer from high background problems for sub‐nanogram quantities of input DNA. Here we report an approach to eliminate this problem for PCR‐based methods even at levels of DNA approaching that of a single cell.
Development of bioadhesives from marine mussels
Authors: Cha Hyung Joon , Hwang Dong Soo , Lim Seonghye 
Published: February 2008

AbstractMussel adhesive proteins have received increased attention as potential biomedical and environmentally friendly underwater adhesives thanks to their fascinating properties, including strong and flexible adhesion, adhesion to various material substrates, water displacement, that they are harmless to human body, and controlled biodegradability. Several mussel adhesive proteins have been identified and characterized from mussels, and profound biochemical knowledge for mussel adhesions has been accumulated. In addition, a lot of effort has been put into realizing the promise of these bioadhesive materials from marine mussels. Here, progress in the diverse developmental approaches, with particular emphasis on functional production of mussel adhesive proteins, are reviewed.
Infrared spectroscopic study of the binding of divalent cations to Akazara scallop troponin C: The effect of the methylene side chain of glutamate residue
Authors: Nara Masayuki , Yumoto Fumiaki , Kagi Hiroyuki , Tanokura Masaru 
Published: February 2008

AbstractAkazara scallop striated adductor muscle troponin C (TnC) binds only one Ca2+ because the three EF‐hand motifs are short of critical residues for the coordination of Ca2+. Fourier‐transform infrared spectroscopy was applied to study coordination structures of M2+ (= Mg2+, Ca2+, Sr2+, and Ba2+) bound in an Akazara scallop TnC mutant (E142D) and the wild‐type TnC C‐lobe in D2O solution. The region of the COO− antisymmetric stretch provides information regarding the coordination modes of a COO− group to a metal ion. The side chain COO− group of Asp142 did not bind to Ca2+ in the bidentate coordination mode, suggesting that the absence of a methylene group is critical for the Ca2+ coordination structure of Akazara scallop TnC (Nara et al., Vib Spect 2006, 42, 188–191). The present study has shown that the absence of a methylene group is not compensated for by a larger metal ion such as Sr2+ or Ba2+. CD spectra showed that the secondary structures are conserved between M2+‐free (apo), Mg2+‐loaded, Ca2+‐loaded, Sr2+‐loaded, and Ba2+‐loaded states, which was consistent with the results estimated from their amide I band patterns. The metal‐ligand interaction at position 12 of site IV is discussed in comparison with the coordination mode of the side chain COO− group of the wild‐type TnC C‐lobe. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 595–599, 2008.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Effects of reduction on the denaturation kinetics of human hair
Authors: Wortmann F.‐J. , Popescu C. , Sendelbach G. 
Published: February 2008

AbstractAlthough human hair as an α‐keratinous fiber exhibits a complex morphology, it can be considered as a nano‐structured filament/matrix composite for the context of thermal analysis. Using differential scanning calorimetry (DSC) in water, the denaturation performance of the α‐helical protein fraction and the effects of reductive treatments were studied. The results are viewed in the context of a previous study for oxidative treatments. It was found that the course of the denaturation process remains generally unperturbed by the treatment, following an irreversible, one‐step, first‐order process. Arrhenius activation energies and pre‐exponential factors were determined from the DSC‐curves by applying the principles of the Friedman‐method. Comparing activation energy values between reductive and oxidative processes shows the differences of the effects on the components of the composite. In contrast, the values of the rate constant at the denaturation temperature, though showing differences in their trends with cumulative treatments, are very similar. This further emphasizes the theory that the viscosity of the matrix affects strict kinetic control over the denaturation of the α‐helical segments. Once the viscosity of the matrix has decreased enough for the denaturation process to occur, this follows a path that is largely independent of the temperature range and of the chemical pre‐history. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 600–605, 2008.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
In vitro interaction between calf thymus DNA and Escherichia coli LPS in the presence of divalent cation Ca2+
Authors: Panja Subrata , Jana Bimal , Aich Pulakesh , Basu Tarakdas 
Published: February 2008

AbstractWith increasing addition of Escherichia coli LPS to calf thymus DNA, both dissolved in CaCl2, absorption maxima of DNA at 260 nm decreased gradually with the appearance of isosbastic points at both ends of spectra, which implied some binding between DNA and LPS. Hill plot of absorbance data showed that the binding interaction was positive cooperative in nature. For any fixed concentration of DNA and LPS, extent of interaction increased as concentration of CaCl2 was raised from 1.0 to 100 mM, signifying the electrostatic nature of the interaction, mediated through Ca2+ ion. Stepwise addition of EDTA, a chelating agent for divalent cations, to DNA–LPS bound complex gradually reversed the spectral shift with increase in absorbance at 260 nm, which implied opening up of the complex, that is, reversible nature of the interaction. Circular dichroism spectral changes of DNA by the addition of LPS indicated partial transition of DNA from B to A form. Isothermal titration calorimetric (ITC) study showed that the DNA–LPS binding was an exothermic and enthalpy‐driven phenomenon. Moreover, in the presence of 100 mM CaCl2, binding constant of the interaction was found to be 2.6 × 104 M−1 and 3.1 × 104 M−1 from the analysis of Hill plot and ITC result, respectively. DNA‐melting study showed that the LPS binding had increased the melting temperature of DNA, indicating more stabilization of DNA double helix. The binding of LPS to DNA made the complex resistant to digestion with endonucleases EcoRI and DNase I. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 606–613, 2008.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Analysis of Organo–Silica Interactions during Valve Formation in Synchronously Growing Cells of the Diatom Navicula pelliculosa
Authors: Heredia Alejandro , van der Strate Han J. , Delgadillo Ivonne , Basiuk Vladimir A. , Vrieling Engel G. 
Published: February 2008

AbstractBiologically formed silica is produced at ambient conditions under the control of molecular and physicochemical processes that are apparently integrated in biosilica morphogenesis, but the mechanisms are not yet fully understood. With the recent identification of small polypeptides and proteins that are encapsulated inside the biosilica and functional in silica polymerization in vitro, it is of importance to determine whether interactions between inorganic silica species and these organic compounds occur in vivo. A time‐resolved analysis of valve formation in synchronously growing cells of the diatom species Navicula pelliculosa enabled us to characterize the relevant chemical bonds by attenuated total reflectance Fourier‐transformed infrared (ATR‐FTIR) spectroscopy. Typically, inorganic bonds of SiOSi (bands at 1058, 843 cm−1), SiOH (3689 cm−1), and PO (1239 cm−1) and organic bonds of proteinaceous matter (with the amide I and II bands at 1642 and 1543 cm−1, respectively) were positively identified during one cycle of valve formation. The observed variations in FTIR band intensity and location represented specific interactions between organic and inorganic molecules during the major silicification event, during which stretching of the SiO bonds was predominantly noticed. The experimentally obtained frequencies (ν) of the major bonds corresponded to those that were obtained by MM+ and PM3 FTIR simulations for organo–silica interactions based on biomolecules that are proposed to be involved in biosilica formation. The results indicated that hydrogen bonds originated from interactions, albeit weak, between organic phosphate or amine groups to the inorganic hydroxyl groups or oxygen atoms from the silicic acid and/or silica. The existence of covalent POSi bonds and electrostatic interactions could not be excluded. These interactions clearly suggest that biomolecules actively contribute to the silica polymerization process during valve formation in N. pelliculosa, and also might act comparably in other diatoms species in which similar biomolecules have been identified.
Patent foramen ovale closure with the Intrasept occluder: Complete 6–56 months follow‐up of 247 patients after presumed paradoxical embolism
Authors: Spies Christian , Timmermanns Ines , Reissmann Ulrich , van Essen Jörg , Schräder Rainer 
Published: February 2008

AbstractObjective:We report our experience of transcatheter patent foramen ovale (PFO) closure with the new Intrasept occluder.Background:The Intrasept device is the fourth generation of the Cardia occluder family. Developed for transcatheter closure of PFO, the main difference between the Intrasept and prior generations of the Cardia occluder is its articulating center post. This modification allows better alignment of the umbrellas on both sides of the atrial septum. We report our experience with this new PFO occluder.Methods:From July 2002 until October 2006, PFO closure with the Intrasept occluder was attempted in 247 patients with presumed paradoxical embolism. Prior to PFO closure, a total of 269 cerebrovascular thromboembolic events (TEs) had occurred. Implantation of the device was guided by fluoroscopy and transesophageal echocardiography with conscious sedation.Results:Median age was 53 years (range, 21–77). One hundred twenty‐seven (51%) patients had an atrial septal aneurysm. The device was implanted successfully in all cases. Acute complications occurred in 4 (1.6%) patients (air embolism = 2, pericardial effusion = 1, supraventricular tachycardia = 1). Follow‐up information is available for all 247 (100%) patients. Median follow‐up time was 14 months (range 6–56). Residual shunt at 6 months follow‐up was 13%. After 1 year, the presence of residual shunt rate decreased to 10%. Following PFO closure, seven recurrent TEs (TIA = 4, CVA = 3) were observed in 6 patients. No wire fractures or device‐associated thrombi were seen.Conclusions:PFO closure with the Intrasept occluder is safe and efficient. Rates of residual shunt and recurrent TE compare favorably with other contemporary devices. © 2008 Wiley‐Liss, Inc.
Pseudoasymmetry: A final twist?
Authors: Chandrasekhar Sosale 
Published: February 2008

AbstractThe original definition of “pseudoasymmetry” conveyed the apparent paradox that a tetrahedral center with four different groups did not result in overall chirality. However, there are problems in applying the concept to cyclic systems that do not contain chirotopic centers. Pseudoasymmetry appears most appropriate to acyclic systems with chirotopic carbon centers, e.g. the meso trihydroxyglutaric acids. Analogous cyclic cases, e.g. the isomeric 1,4‐dimethylcyclobutanes, are best treated as diastereomers, and may indeed be described by an interesting extension of the like–unlike notation. Remarkably, in several tri‐ and tetramethylcyclohexanes, CIP descriptors cannot be applied even to chirotopic centers, which can only be described by the modified l–u notation. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Microscale HPLC enables a new paradigm for commercialization of complex chiral stationary phases
Authors: Welch Christopher J. , Hyun Myung Ho , Kubota Takateru , Schafer Wes , Bernardoni Frank , Choi Hee Jung , Wu Naijun , Gong Xiaoyi , Lipshutz Bruce 
Published: February 2008

AbstractThe small column size (0.3 mm i.d. × 15 cm) used in microscale HPLC contains only a small fraction (<1%) of the chromatographic packing material of a typical analytical HPLC column. Consequently, chromatographic stationary phases that are prohibitively expensive in conventional HPLC, owing either to synthetic complexity or costly starting materials, may become commercially viable in the microscale format. To illustrate this point, a previously described, synthetically complex, crown ether chiral stationary phase was prepared and evaluated in the microscale format, showing excellent separation of the enantiomers of underivatized amine analytes. Chirality 2008. © 2008 Wiley‐Liss, Inc.
Is there an optimal comorbidity index for prostate cancer?
Authors: Alibhai Shabbir M. H. , Leach Marc , Tomlinson George A. , Krahn Murray D. , Fleshner Neil E. , Naglie Gary 
Published: February 2008

AbstractBACKGROUND.Comorbidity is an important consideration in oncology practice, particularly among older patients. Although a variety of comorbidity indices have been employed in research studies, it is unclear whether any one index is preferred.METHODS.An age‐stratified random sample of 345 men (mean age of 69 years) who were newly diagnosed with prostate cancer were identified from a cancer registry in Ontario, Canada. Comorbidity and treatment information were obtained from chart review. Four comorbidity indices were utilized: Charlson Index, Diagnosis Count, Index of Coexistent Disease (ICED), and number of medications. Logistic regression analysis was used to compare the performance of comorbidity measures with respect to predicting receipt of curative treatment (radical prostatectomy or radiotherapy) and overall 6‐year survival. Multivariable model performance including each of the comorbidity measures was compared by calculating the area under the receiver operating characteristic curve (AUROC).RESULTS.Among men with localized disease (n = 231), in models adjusted for age, Gleason score, and prostate‐specific antigen level, only the Charlson Index was found to be a statistically significant predictor of receipt of curative treatment (P < .05), although all comorbidity indices had similar AUROC in adjusted models. After a median follow‐up of 6.5 years, 116 of 345 men (33.6%) had died. In adjusted models, all 4 comorbidity indices performed similarly in predicting overall survival.CONCLUSIONS.Although comorbidity is an important predictor of both curative treatment and overall survival in prostate cancer, the optimal comorbidity index for use in research remains unclear. Selecting the optimal comorbidity index may depend on both the specific patient population and the outcome being considered. Cancer 2008. © 2008 American Cancer Society.
A nomogram predicting long‐term biochemical recurrence after radical prostatectomy
Authors: Suardi Nazareno , Porter Christopher R. , Reuther Alwyn M. , Walz Jochen , Kodama Koichi , Gibbons Robert P. , Correa Roy , Montorsi Francesco , Graefen Markus , Huland Hartwig , Klein Eric A. , Karakiewicz Pierre I. 
Published: February 2008

AbstractBACKGROUNDMen who undergo radical prostatectomy (RP) are at long‐term risk of biochemical recurrence (BCR). In this report, the authors have described a model capable of predicting BCR up to at least 15 years after RP that can adjust predictions according to the disease‐free interval.METHODSCox regression was used to model the probability of BCR (a prostate‐specific antigen level >0.1 ng/mL and rising) in 601 men who underwent RP with a median follow‐up of 11.4 years. The statistical significance of nomogram predictors was confirmed with a competing‐risks regression model. The model was validated internally with 200 bootstraps and externally at 5 years, 10 years, and 15 years in 2 independent cohorts of 2963 and 3178 contemporary RP patients from 2 institutions.RESULTSThe 5‐year, 10‐year, 15‐year, and 20‐year actuarial rates of BCR‐free survival were 84.8%, 71.2%, 61.1%, and 58.6%, respectively. Pathologic stage, surgical margin status, pathologic Gleason sum, type of RP, and adjuvant radiotherapy represented independent predictors of BCR in both Cox and competing‐risks regression models and constituted the nomogram predictor variables. In internal validation, the nomogram accuracy was 79.3%, 77.2%, 79.7%, and 80.6% at 5 years, 10 years, 15 years, and 20 years, respectively, after RP. In external validation, the nomogram was 77.4% accurate at 5 years in the first cohort and 77.9%, 79.4%, and 86.3% accurate at 5 years, 10 years, and 15 years, respectively, in the second cohort.CONCLUSIONSPatients who undergo RP remain at risk of BCR beyond 10 years after RP. The nomogram described in this report distinguishes itself from other tools by its ability to accurately predict the conditional probability of BCR up to at least 15 years after surgery. Cancer 2008. © 2008 American Cancer Society.
Multiple gene methylation of nonsmall cell lung cancers evaluated with 3‐dimensional microarray
Authors: Wang Yan , Zhang Dingdong , Zheng Wenli , Luo Junfeng , Bai Yunfei , Lu Zuhong 
Published: February 2008

AbstractBACKGROUNDAberrant DNA methylation of the CpG islands for cancer‐related genes is among the earliest and most frequent alterations in cancer and may be useful for diagnosing cancer or evaluating recurrent disease.METHODSIn this study, a 3‐dimensional (3‐D), polyacrylamide gel‐based DNA microarray coupled with linker‐polymerase chain reaction (PCR) was developed to detect hypermethylation of CpG islands in multiple genes from a large group of different samples. The authors determined the frequency of aberrant promoter methylation of 15 genes in 28 resected primary nonsmall cell lung cancers (NSCLCs) and in 12 corresponding nonmalignant lung tissues.RESULTSMethylation frequencies in the tumor samples were detected in 18% of samples for the breast cancer 1 gene BRCA1, in 43% of samples for the tissue inhibitor of metalloproteinase 3 gene TIMP‐3, in 38% of samples for the cyclin‐dependent kinase inhibitor 4A gene p16INK4a, in 54% of samples for the cadherin 13 gene CDH13, in 50% of samples for the death‐associated protein kinase gene DAPK, in 11% of samples for the E‐cadherin gene ECAD, in 25% of samples for the insulin‐like growth factor binding protein 7 gene IGFBP7, in 18% of samples for the Ras association domain family 1 gene RASSF1, in 68% of samples for the adenomatous polyposis coli gene APC, in 7% of samples for the cyclin‐dependent kinase inhibitor gene p15, in 18% of samples for the CD44 cell adhesion molecule gene, in 29% of samples for the human Mut‐L homolog gene hMLH, in 32% of samples for the human telomerase reverse transcriptase gene hTERT, in 64% of samples for the calcitonin gene‐related polypeptide α gene CALCA, and in 54% of samples for the estrogen receptor gene ER; however, methylation was not observed in the majority of corresponding nonmalignant tissues. Six samples in from 28 tumors had >6 genes methylated, and 1 sample had 13 genes methylated. Methylation of these genes was correlated with some clinicopathologic patient characteristics.CONCLUSIONSThis study demonstrated that a 3‐D microarray could be used to detect DNA hypermethylation and provided a high‐throughput platform for DNA hypermethylation analysis. Cancer 2008. © 2008 American Cancer Society.
Dying with cancer
Authors: Kendal Wayne S. 
Published: February 2008

AbstractBACKGROUNDCancer survival is influenced by age, comorbidity, and type of cancer. A population‐based study was conducted to compare the interplay between age and mortality for different cancers.METHODSThis study analyzed 784,378 cases, comprising 22 of the commonest SEER cancers diagnosed between 1984 and 1993. Competing hazards and proportional hazard analyses for cancer‐specific and comorbid death were performed.RESULTSMedian follow‐up was up to 159 months, and the median age of diagnosis was 67 years. Cancer‐specific and comorbid deaths accumulated most within the first years of diagnosis. With the more biologically aggressive cancers, cancer deaths invariably exceeded comorbid deaths. For the remaining 70% of cancers, comorbidity remained the dominant mode of death. Deaths attributable to both cancer and comorbidity accumulated mostly after the seventh decade of life. Cancer site had a 3‐fold greater effect on overall survival than age at diagnosis and a 30‐fold effect with cancer‐specific survival; age at diagnosis had a 5‐fold greater effect on comorbid deaths than site.CONCLUSIONSBoth the age of the affected individual and the biology of the particular cancer have major influences on cancer survival and mode of death. Cancer is largely a disease of the elderly. Within affected individuals, fatalities attributable to cancer and comorbidity appeared inter‐related, with cancer‐specific deaths dominating for more lethal cancers and comorbid deaths dominating for the remaining majority. For these reasons, further improvements in overall survival may be best anticipated from better geriatric and general medical management as much as from better cancer management. Cancer 2008. © 2008 American Cancer Society.