bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for structural and functional diversity among SDS-resistant SNARE complexes in neuroendocrine cells
Authors: Kubista Helmut , Edelbauer Hannah , Boehm Stefan 
Published: February 2004

The core complex, formed by the SNARE proteins synaptobrevin 2, syntaxin 1 and SNAP-25, is an important component of the synaptic fusion machinery and shows remarkable in vitro stability, as exemplified by its SDS-resistance. In western blots, antibodies against one of these SNARE proteins reveal the existence of not only an SDS-resistant ternary complex but also as many as five bands between 60 and &gt;200 kDa. Structural conformation as well as possible functions of these various complexes remained elusive.
In western blots of protein extracts from PC12 cell membranes, an antibody against SNAP-25 detected two heat-sensitive SDS-resistant bands with apparent molecular weights of 100 and 230 kDa. A syntaxin antibody recognized only the 230 kDa band and required heat-treatment of the blotting membrane to detect the 100 kDa band. Various antibodies against synaptobrevin failed to detect SNARE complexes in conventional western blots and detected either the 100 kDa band or the 230 kDa band on heat-treated blotting membranes.
When PC12 cells were exposed to various extracellular K+-concentrations (to evoke depolarization-induced Ca2+ influx) or permeabilized in the presence of basal or elevated free Ca2+, levels of these SNARE complexes were altered differentially: moderate Ca2+ rises (≤1 μM) caused an increase, whereas Ca2+ elevations of more than 1 μM led to a decrease in the 230 kDa band. Under both conditions the 100 kDa band was either increased or remained unchanged.
Our data show that various SDS-resistant complexes occur in living cells and indicate that they represent SNARE complexes with different structures and diverging functions. The distinct behavior of these complexes under release-promoting conditions indicates that these SNARE structures have different roles in exocytosis.
Cyclobutadiene Dianion
Authors: Matsuo Tsukasa , Sekiguchi Akira 
Published: February 2004

Abstract
In this account, we present the synthesis and chemistry of the dilithium salts of the cyclobutadiene dianion (CBD2−), which contains a doubly charged four-membered ring system. The transmetalation reaction of tetrasilyl-substituted cyclobutadiene (CBD) cobalt complexes (5,6) with lithium metal led to the formation of the corresponding dilithium salts of CBD2− (10,11). The aromaticity of the CBD2− species has been studied on the basis of structural characteristics and magnetic properties. The dilithium salts of CBD2− stabilized by both phenyl and silyl groups (12–14) were also prepared by a similar procedure, starting from the corresponding CBD cobalt complexes (7–9). The CBD2− species have been fully characterized by NMR studies and X-ray crystallography. The two-electron oxidation reaction of the tetrasilyl-CBD2− (10,11) with 1,2-dibromoethane produced the neutral CBD derivatives (17,22). The structures, properties, and reactivities of the tetrasilyl-substituted CBD are also reviewed here. Tetrakis(trimethylsilyl)tetrahedrane (26) was synthesized by irradiation of tetrakis(trimethylsilyl)cyclobutadiene (17). The structure and properties of tetrahedrane (26) are presented.
Optically Active Polymers for Chiral Separation
Authors: Yamamoto Chiyo , Okamoto Yoshio 
Published: February 2004

Abstract
One of the most practically important functions of optically active polymers is chiral recognition. In the past two decades, various optically active polymers have been utilized as the chiral stationary phases (CSPs) for high-performance liquid chromatography, which is today the most powerful and practical method not only for analyzing enantiomers but also for obtaining them in a pure form. In this account, the emphasis lies on the polymethacrylate and polysaccharide derivatives that we have developed. One-handed helical poly(triphenylmethyl methacrylate) has been prepared by asymmetric anionic polymerization and shows high chiral recognition, especially for the compounds which have no functional groups. Polysaccharide derivatives, particularly cellulose and amylose phenylcarbamates, can resolve a wide range of racemates, and their abilities are significantly influenced by the substituents introduced on the phenyl moieties. Cellulose and amylose cycloalkylcarbamates and chitin phenylcarbamates also show high chiral recognition; the former can be utilized as the CSPs for thin-layer chromatography because of the absence of UV absorption. The immobilization of the polysaccharide derivatives onto a silica support via chemical bonding improves their durability for various solvents and also their resolving ability for some compounds. Several phenylcarbamates are soluble in chloroform, which allowed one to study their chiral recognition mechanism at a molecular level, particularly by NMR spectroscopy. A computational method can also be applied for mechanistic studies.
ESR Spin Probe Investigation of Chain Ordering of a Triglycerol Membrane
Authors: Nakagawa Kouichi 
Published: February 2004

Abstract
The chain ordering of a triglycerol membrane was investigated by continuous wave (CW) electron spin resonance (ESR) in conjunction with a spin probe method. Order parameters (S0) obtained by a slow-tumbling computational analysis for 7-doxylstearic acids (7-DSA), 12-DSA, and 16-DSA in poly(oxyethylene) hydrogenated castor oil (HCO) membrane at 20 °C were 0.68, 0.25, and 0.04, respectively. The S0 results suggest that the membrane chains are well ordered around the probe moiety for 7-DSA and very fluid around the 16-DSA moiety in the HCO membrane. The relative magnitude of the chain order for 12-DSA was very different from that obtained by the conventional order parameter using hyperfine coupling values. The conventional hyperfine analysis cannot verify the subtle spectral changes for 12-DSA. Moreover, the S0 values for 7- and 12-DSA decreased differently when the temperature increased. Thus, the results obtained by a slow-tumbling simulation revealed detailed membrane chain ordering.
Three Types of Nickel(II) Complexes Derived from 2-Substituted Benzothiazoline; Formation of a Tetranuclear Complex by a Sterically Induced Orthometallation Reaction
Authors: Kawamoto Tatsuya , Kushi Yoshihiko 
Published: February 2004

Abstract
The reaction of 2-(2,4-dichlorophenyl)benzothiazoline with nickel(II) acetate tetrahydrate in ethanol has afforded the monohelical bis[2-(2,4-dichlorophenylmethyleneamino)benzenethiolato]nickel(II) ([Ni(HL1)2] (1)). The X-ray structure of 1 has revealed that ortho-phenyl hydrogen atoms of pendant arms are oriented to the nickel center in a monohelical structure. The low-field resonance for their ortho-protons in the 1H NMR spectrum indicates that the Ni···H–C interaction is maintained in solution. Heating 1 in toluene gave a square-planar nickel(II) complex with a non-innocent ligand ([Ni(L2)] (2)), and prolonged heating yielded a thiolato-bridged tetranuclear nickel(II) complex ([Ni4(L1)4] (3)). The tetranuclear complex 3 was formed from activation of the ortho C–H bond, not the C–Cl bond, through sterically controlled Ni···H–C contacts in 1. The molecular structures of 2 and 3 have also been determined by X-ray crystallographic methods.
Determination of the Toxic Lead Level in Cosmetic-Hair Dye Formulations Using a Screen-Printed Silver Electrode
Authors: Shih Ying , Zen Jyh-Myng , Senthil Kumar Annamalai , Lee Yi-Chien , Huang Hui-Rou 
Published: February 2004

Abstract
A disposable-type screen-printed non-single crystal silver electrode (AgSPE) surface has been demonstrated for the sensitive and selective quantification of lead in cosmetic hair-dye formulations using its underpotential deposition (UPD-Pb) process.
Exciplex Emission of Carbazole–Terephthalate Cyclophane and Its Application as a Fluorescent Probe for Local Polarity of Solvents
Authors: Benten Hiroaki , Ohkita Hideo , Ito Shinzaburo , Yamamoto Masahide , Tohda Yasuo , Tani Keita 
Published: February 2004

Abstract
Photophysical properties of carbazole–terephthalate cyclophane (Cz–TP) were studied. The absorption spectra of Cz–TP in various solvents were slightly broadened due to the distortion of the carbazole (Cz) moiety and became similar to that of a reference compound of carbazole–benzene cyclophane (Cz–Bz). The absorption spectrum and the peak wavelengths of Cz–TP were insensitive to the solvent polarity. These findings show that there is transannular π–π electronic interaction between the Cz and TP moieties but that the charge transfer interaction from the Cz to TP moieties is small in the ground state. On the other hand, the emission spectrum was broad, structureless, and red-shifted compared with that of the reference compound. The peak wavelength of the emission was shifted to a longer wavelength with increases in the dielectric constant of solvents. The peak shift was quantitatively explained by the Lippert–Mataga formula. Therefore, we conclude that the broad emission is due to the intramolecular exciplex in Cz–TP. The dielectric constant of 2-methyl tetrahydrofuran was evaluated from the exciplex emission of Cz–TP ranging from 77 to 292 K, indicating that the Cz–TP molecule is an excellent polarity probe not only in a liquid phase but also in a solid phase over a wide temperature range.
Post-exposure prophylaxis for human immunodeficiency virus infection in the Royal Infirmary of Edinburgh - an audit
Authors: Manavi K , McMillan A , Paterson J 
Published: February 2004

The purpose of the audit was to assess the implementation of the protocols developed by Lothian University National Health Service Trust for post-exposure prophylaxis (PEP) against blood-borne virus infections. Patients at risk of infection after an injury were referred to the Department of Genitourinary Medicine (GUM) Edinburgh Royal Infirmary for assessment. A brief description of the incident, the time of the incident, the time of referral and the decision made was documented. The notes of these patients were reviewed 12 months later for the results of prospective HIV test after each incident. There were 76 referrals to the GUM Department in year 2001. Occupational Health (OH) and the Accident and Emergency (A&E) Departments each made 35 referrals. The latter cases were exposures in community settings. Amongst A&E referrals the time interval between the incident and assessment was significantly longer than for OH referrals ( P = 0.001). Female health workers reported exposure incidents sooner than their male counterparts ( P = 0.01). Post-exposure prophylaxis for HIV was offered to 22 (29%) of 76 referred individuals, and was accepted by 13 (59%) persons. The course of PEP drugs was discontinued by five (38%) of the 13 individuals after consented postincident HIV testing of the source patients showed that they were HIV-seronegative. Five of eight individuals completed the course of PEP medication. Only 11 (14%) persons attended for serological testing for blood-borne virus infection three or more months after exposure. None of these 11 persons, one of whom had been given PEP medication, had become infected. Further training and emphasis on the necessity of immediate reporting of occupational incidents and consented post-incident HIV testing of the source patient is needed. The current guidelines appear to work fairly well, but further counselling of those with significant injuries to undertake HIV serological testing after appropriate time interval is required.
Remission of Behçet's disease and keratoconjunctivitis sicca in an HIV-infected patient treated with HAART
Authors: Cicalini S , Gigli B , Palmieri F , Boumis E , Froio N , Petrosillo N 
Published: February 2004

A 34-year-old woman presented with a 10-year history of recurrent oral and genital ulcerations and recurrent episodes of bilateral conjunctivitis associated with HIV infection. A diagnosis of Behçet's disease (BD) in association with keratoconjunctivitis sicca (KCS) was made after exclusion of other viral and autoimmune diseases according to the international criteria for BD. This is the first reported case of a combination of BD and KCS in a patient with HIV infection in which a complete resolution was observed as a result of successful highly active antiretroviral therapy. The likelihood that a direct viral effect or HIV-induced autoimmune mechanisms act in the pathogenesis of both BD and KCS in HIV-infected patients is discussed.
Extramammary Paget's disease masquerading as lichen sclerosus
Authors: Bansal D , Bowman C A 
Published: February 2004

A wide range of genital infections and skin conditions may present with vulval pruritus. Lichen sclerosus is one cause. This is often associated with visible skin changes which include atrophy, resorption or fusion of the labia, sclerosis and excoriation. Ulceration may indicate malignant transformation and requires urgent biopsy. Many experienced clinicians diagnose lichen sclerosus on clinical appearance, however we recommend a low threshold for biopsy, especially for non-responding or odd looking lesions. We report a patient whose vulval skin biopsy for clinically suspected lichen sclerosus revealed extramammary Paget's disease of the vulva. We review the pathology, prognosis and treatment of this condition.
Early Experiences and Clinical Implications of Drug-Eluting Stents: Part 1
Authors: Chong Pang H , Cheng Judy WM 
Published: February 2004

OBJECTIVE To review the pathogenesis of in-stent restenosis and the evolution of drug-eluting stents (DES). DATA SOURCES Using the search terms sirolimus, paclitaxel, and drug-eluting stents, a literature review was conducted to identify peer-reviewed articles and abstracts in MEDLINE (1966—June 2003). Recent meeting abstracts were accessed through the American Heart Association and the American College of Cardiology Web sites. Citations from available articles were also reviewed for additional references. STUDY SELECTION AND DATA EXTRACTION Published reviews and studies showing the effects of in-stent restenosis and drug-coated and -eluting stents were evaluated and reviewed. DATA SYNTHESIS Coronary stent implantation is a common form of percutaneous coronary interventions. Approximately 20–30% of patients undergoing stent placement develop restenosis 6 months after the procedure. The primary cause of in-stent restenosis is neointimal proliferation and subsequent accumulation of extracellular matrix, collagen, and macrophages. Eluting stents with an antimitotic agent may reduce the extent of restenosis. Research is ongoing in terms of finding the ideal combination of antimitotic agent, stent, and eluting medium to create the perfect stent. CONCLUSIONS Research over the last decade has led to a better understanding of the pathogenesis of in-stent restenosis and ways to prevent restenosis. DES are being developed as one of the strategies to prevent restenosis.
Inert Medication Ingredients Causing Nonadherence Due to Religious Beliefs
Authors: Sattar S Pirzada , Ahmed Mohammed Shakeel , Majeed Farhan , Petty Frederick 
Published: February 2004

OBJECTIVE To report 4 cases of medication nonadherence due to presence of inert ingredients forbidden by the patients’ religion. CASE SUMMARIES We describe 4 cases in which religious concerns about prescribed medications’ inert components led to discontinuation of these medications. These inert components are gelatin and stearic acid, which might be derived from pork or beef products. In these 4 cases, patients of Muslim, Orthodox Christian, and Seventh Day Adventist faiths, who consider it against their religion to consume pork products, stopped their medications on discovering this possibility. This led to relapse of their illnesses. DISCUSSION These cases demonstrate that, for some patients, inert medication components that are forbidden by their religion may lead to discontinuation of medications. This could lead to relapse of symptoms and might even lead to hospitalization. Therefore, it is important for prescribers to inform patients of this possibility when treating patients whose religious background might conflict with these inert medication components. CONCLUSIONS Patients with religion prohibitions against consumption of pork and/or beef products might stop their medications when prescribed those with pork- and beef-derived gelatin and/or stearic acid. Prescribers should discuss this possibility with their patients, perhaps as part of informed consent.
Improvement in Sensitivity of Allele-specific PCR Facilitates Reliable Noninvasive Prenatal Detection of Cystic Fibrosis
Authors: Nasis Ourania , Thompson Shanel , Hong Tom , Sherwood Margaret , Radcliffe Shawn , Jackson Laird , Otevrel Tomas 
Published: February 2004

Abstract
Background: Cell-free fetal DNA circulating in maternal blood has potential as a safer alternative to invasive methods of prenatal testing for paternally inherited genetic alterations, such as cystic fibrosis (CF) mutations.
Methods: We used allele-specific PCR to detect mutated CF D1152H DNA in the presence of an excess of the corresponding wild-type sequence. Pfx buffer (Invitrogen) containing replication accessory proteins and Taq polymerase with no proofreading activity was combined with TaqMaster PCR Enhancer (Eppendorf) to suppress nonspecific amplification of the wild-type allele. The procedure was tested on DNA isolated from plasma drawn from 11 pregnant women (gestational age, 11–19.2 weeks), with mutation confirmation by chorionic villus sampling.
Results: The method detected 5 copies of the CF D1152H mutant allele in the presence of up to ∼100 000 copies of wild-type allele without interference from the wild-type sequence. The D1152H mutation was correctly identified in one positive sample; the only false-positive result was seen in a mishandled sample.
Conclusions: This procedure allows for reliable detection of the paternally inherited D1152H mutation and has potential application for detection of other mutations, which may help reduce the need for invasive testing.
Analytic Performance of Immunoassays for Drugs of Abuse Below Established Cutoff Values
Authors: Luzzi Veronica I , Saunders Al N , Koenig John W , Turk John , Lo Stanley F , Garg Uttam C , Dietzen Dennis J 
Published: February 2004

Abstract
Background: The analytic performance and accuracy of drug detection below Substance Abuse and Mental Health Services Administration (SAMHSA) cutoffs is not well known. In some patient populations, clinically significant concentrations of abused drugs in urine may not be detected when current SAMHSA cutoffs are used. Our objectives were to define the precision profiles of three immunoassay systems for drugs of abuse and to evaluate the accuracy of testing at concentrations at which the CV was &lt;20%.
Methods: Drug-free urine was supplemented with analytes to assess the precision in three commercial drugs-of-abuse immunoassay systems below the SAMHSA-dictated cutoffs for amphetamines, opiates, benzoylecgonine, phencyclidine, and cannabinoids. Consecutive urine samples with signals associated with a CV &lt;20% by Emit® immunoassay and below SAMHSA cutoffs were then subjected to confirmatory analysis.
Results: The CV of all immunoassay systems tested remained &lt;20% to drug concentrations well below SAMHSA cutoffs. The accuracy of urine drug-screening results between the SAMHSA-specified cutoffs and the precision-based cutoffs was less than accuracy for specimens above the SAMHSA cutoffs, but the use of the precision-based cutoff produced a 15.6% increase in the number of screen-positive specimens and a 7.8% increase in the detection of specimens that yielded positive results on confirmatory testing.
Conclusion: The precision of three commercial immunoassay systems for drugs-of-abuse screening is adequate to detect drugs below SAMHSA cutoffs. Knowledge of the positive predictive values of screening immunoassays at lower cutoff concentrations could enable efficient use of confirmatory testing resources and improved detection of illicit drug use.
Development of an Immunofluorometric Assay and Quantification of Human Kallikrein 7 in Tissue Extracts and Biological Fluids
Authors: Kishi Tadaaki , Soosaipillai Antoninus , Grass Linda , Little Sheila P , Johnstone Edward M , Diamandis Eleftherios P 
Published: February 2004

AbstractBackground: Human kallikrein 7 (hK7), also known as human stratum corneum chymotryptic enzyme, is a chymotrypsin-like serine protease first identified in human skin extracts and predicted to be a secreted protease. The aim of this study was to develop a sensitive and specific immunoassay for hK7 and to examine the distribution of hK7 in tissue extracts and biological fluids.Methods: Recombinant hK7 was produced in human embryonic kidney cells (HEK293T) and purified by a three-step column chromatographic procedure. The purified hK7 was injected into mice for antibody generation. A sandwich-type immunoassay was developed with the anti-hK7 monoclonal antibodies.Results: The assay had imprecision (CV) &lt;10% through the dynamic range of 0.2–20 μg/L and had no detectable cross-reactivity from other members in the human kallikrein gene family. Highest concentrations were found in skin, esophagus, and kidney. hK7 was also found in amniotic fluid, ascites from ovarian cancer patients, breast milk, cerebrospinal fluid, saliva, seminal plasma, serum, sweat, synovial fluid, and urine.Conclusions: This study describes the first ELISA-type immunoassay for hK7 protein quantification. hK7 is found many human tissues and in various biological fluids.
Mathematical comparison between volume of distribution (V) and volume of distribution at steady‐state (Vss) utilizing model‐independent approach
Authors: Sobol Eyal , Bialer Meir 
Published: February 2004

AbstractPharmacokinetic textbooks state that the (apparent) volume of distribution based on drug concentration in plasma (V or Vβ) is always greater than the volume of distribution (apparent) under steady state conditions (Vss), but do not provide a general model‐independent mathematical proof. Wagner's mathematical comparison between Vβ and Vss is based on microscopic rate constants of either specific models and is restricted solely to the two‐compartment open body model. Nakashima and Benet utilizing a model‐dependent approach showed a mathematical relationship between Vβ and Vss for a multicompartment model, but again by using microscopic model constants. The limitation of these two above mentioned mathematical comparisons is the necessity of knowledge of the model's structure and its microscopic rate constants. The present article describes a new non‐compartmental, model‐independent, general mathematical proof for Vβ to be always greater than Vss. This new method does not require any knowledge of microscopical rate constants and is based solely on an exponentially decreasing function, which is the common way to describe drug disposition following i.v. bolus. Copyright © 2004 John Wiley & Sons, Ltd.