bluuebunny/crossref_metadata_2025 huggingface dataset:
Interactions of sperm perinuclear theca with the oocyte: Implications for oocyte activation, anti‐polyspermy defense, and assisted reproduction
Authors: Sutovsky Peter , Manandhar Gaurishankar , Wu Alex , Oko Richard
Published: June 2003

Perinuclear theca (PT) is the cytoskeletal coat of mammalian sperm nucleus that is removed from the sperm head at fertilization. PT harbors the sperm borne, oocyte‐activating factor (SOAF), a yet‐to‐be‐characterized substance responsible for triggering the signaling cascade of oocyte activation, thought to be dependent on intra‐oocyte calcium release. The present article reviews the current knowledge on the biogenesis and molecular composition of sperm PT. Possible functions of sperm PT during natural and assisted fertilization, and in the initiation of embryonic development are discussed. Furthermore, evidence is provided that SOAF is transferred from the sperm PT to oocyte cytoplasm through the internalization and rapid solubilization of the post‐acrosomal PT. It is shown that during natural fertilization the sperm PT dissolves in the oocyte cytoplasm concomitantly with sperm nuclear decondensation and the initiation of pronuclear development. SOAF activity is preserved in the differentially extracted sperm heads only if the integrity of PT is maintained. After intracytoplasmic sperm injection (ICSI), activation occurs only in those oocytes in which the injected spermatozoon displays complete or partial dissolution of PT. In the latter case, the residual PT of the sub‐acrosomal and/or post‐acrosomal sperm region may persist on the apical surface of the sperm nucleus/male pronucleus and may cause a delay or arrest of zygotic development. We propose that the sperm PT harbors SOAF in the post‐acrosomal sheath, as this is the first part of the sperm cytosol to enter the oocyte cytoplasm and its disassembly appears sufficient to initiate the early events of oocyte activation. Dissolution of the sub‐acrosomal part of the PT, on the other hand, appears necessary to insure complete DNA decondensation in the internalized sperm nucleus and initiate DNA synthesis of both pronuclei. The release of the SOAF from the sperm head into oocyte cytoplasm at fertilization ultimately leads to the activation of oocyte mechanism including the completion of the meiotic cell cycle, pronuclear development and anti‐polyspermy defense. Microsc. Res. Tech. 61:362–378, 2003. © 2003 Wiley‐Liss, Inc.
Polyspermy prevention in marine invertebrates
Authors: Gould Meredith C. , Stephano Jose Luis
Published: June 2003

In marine invertebrates, as in most other organisms, normal development requires that only one sperm nucleus joins with the egg nucleus at fertilization. The principal mechanisms employed are (1) prevention of sperm‐egg plasma membrane fusion and (2) modifications of the egg extracellular coat to prevent sperm binding and/or penetration. In a third strategy, fertilization is polyspermic, but only one sperm nucleus fuses with the egg nucleus. Other factors such as gamete density during spawning, chemotaxis, and localized sites for sperm entry may also affect the numbers of sperm reaching the egg. Microsc. Res. Tech. 61:379–388, 2003. © 2003 Wiley‐Liss, Inc.
The relationship between BCL6 bodies and nuclear sites of normal and halogenated DNA and RNA synthesis
Authors: Puvion‐Dutilleul Francine , Souquere‐Besse Sylvie , Albagli‐Curiel Olivier
Published: June 2003

BCL6 is a POZ/BTB and zinc finger transcription factor that self‐interacts and accumulates into discrete nuclear “bodies” of unknown function. We recently reported that BCL6 bodies associate with bromodeoxyuridine (BrdU)‐substituted DNA, suggesting their implication in replication. To examine this possibility, we examine here by electron and confocal microscopy the relation between BCL6 bodies and replication foci (RF) using incorporation of various halogenated nucleotides (BrdU, chlorodeoxyuridine, CldU, and iododeoxyuridine, IdU) or PCNA (proliferating cell nuclear antigen) staining. We show that BCL6 bodies are found associated with RF, as revealed by PCNA staining. However, such association is markedly prolonged upon BrdU or CldU incorporation, but less, or not at all, upon IdU incorporation. Pulse‐chase and double‐labeling experiments indicate that IdU‐substituted DNA leaves BCL6 bodies after a few tenths of minutes while BrdU‐ or CldU‐substituted DNA stalls in their vicinity for several hours, thereby giving the characteristic “crowns” of DNA entirely surrounding BCL6 bodies. In all cases, however, the halogenated DNA ends up undergoing a movement from BCL6 bodies toward nucleoplasm and nuclear periphery to reach euchromatin and heterochromatin, respectively. We propose that replicating DNA is prone to be bound by BCL6, while BrdU/CldU incorporation increases this propensity possibly because these two events have synergistic effects on the structure and chromatinisation of the newly synthesized DNA. Finally, despite the known proximity between nuclear sites of transcription and replication, we show via several approaches that BCL6 bodies do not appear to be involved either in RNA synthesis or storage. Microsc. Res. Tech. 61:389–407, 2003. © 2003 Wiley‐Liss, Inc.
Hexosaminidase A deficiency is an uncommon cause of a syndrome mimicking amyotrophic lateral sclerosis
Authors: Drory Vivian E. , Birnbaum Miriam , Peleg Leah , Goldman Boleslaw , Korczyn Amos D.
Published: June 2003

Patients with adult hexosaminidase A (Hex A) deficiency may have clinical manifestations similar to amyotrophic lateral sclerosis (ALS). Mutations in the hexosaminidase A (HEXA) gene are common in the Jewish Ashkenazi population in Israel. Serum samples of 115 Israeli patients with sporadic ALS were screened for enzymatic activity to detect “enzyme‐based carriers.” Fifteen samples with low (< 50%) enzymatic activity were subjected to mutation analysis, which included the two common mutations in the HEXA gene among Ashkenazi Jews (+1278TATC and IVS12+1G→C). Three “enzymatic carrier” patients of Moroccan origin were checked for two additional mutations (ΔF304/305 and Arg170→Gln), specific to this ethnic group. Two “enzymatic carrier” patients of Iraqi origin were analyzed for the mutation Gly250→Val, specific to this population. The mutation Gly 269→Ser was screened in carriers of Ashkenazi origin only (n = 10). The only abnormalities found were heterozygous +1278TATC mutations in two Ashkenazi patients. Their clinical presentation was not different from that usually encountered in ALS. The frequency of mutations in the HEXA gene among Israeli ALS patients was not higher than in the healthy Israeli population. Therefore, Hex A deficiency seems to be a very unlikely cause of an ALS‐mimic syndrome. Muscle Nerve 28: 109–112, 2003
Quantitative measurement of muscle fiber composition in a normal population
Authors: Toft Ingrid , Lindal Sigurd , Bønaa Kaare H. , Jenssen Trond
Published: June 2003

To obtain normative muscle morphology data on a healthy population recruited from a population survey, we examined vastus lateralis biopsies from 58 men and 33 women, aged 26–67 years. Biopsies were measured with automated, computer‐aided techniques. Data were analyzed according to gender and age, and the influence of blood pressure, body mass index (BMI), and smoking habits was also examined. Men had larger muscle fibers (fiber area ∼5,400 μm2) than women (∼4,000 μm2,P= 0.003). No gender differences were seen in fiber composition, fiber roundness, percentage of connective tissue, or capillary density. Blood pressure did not influence fiber size or composition, but was correlated with fiber roundness in men. BMI was associated with fiber area in men, but not in women. Variations in age, smoking habits, and physical activity did not influence muscle morphology data substantially. Thus, in a normal population, men have larger muscle fibers than women, but similar fiber composition. Variation in gender, BMI, blood pressure, and physical activity may influence morphological features to a minor degree. Muscle Nerve 28: 101–108, 2003
Adult Hallervorden–Spatz syndrome simulating amyotrophic lateral sclerosis
Authors: Vasconcelos O. M. , Harter D. H. , Duffy C. , McDonough B. , Seidman J. G. , Seidman C. E. , Campbell W. W.
Published: June 2003

Hallervorden–Spatz syndrome (HSS) is a neurodegenerative disorder characterized by progressive dementia, dystonia, ataxia, and rigidity. An atypical form of adult‐onset HSS was observed in a 36‐year‐old man presenting with progressive dysarthria. Markedly dysarthric speech and a weak atrophic tongue associated with a neurogenic pattern of motor unit recruitment in bulbar‐supplied muscles on electromyography led to an initial impression of bulbar amyotrophic lateral sclerosis (ALS). Lack of expected progression of symptoms, however, prompted reinvestigation. Repeat brain magnetic resonance imaging demonstrated an “eye‐of‐the‐tiger” pattern in the basal ganglia, characteristic of HSS, thus requiring genetic studies. DNA analyses of the pantothenate kinase gene (PANK2) was conducted and revealed two novel, disease‐causing exon 3 missense mutations (Cys231Ser and Tyr251Cys). This case broadens the genotypic and phenotypic spectrum of HSS to include a late‐onset syndrome resembling bulbar‐onset ALS. Muscle Nerve 28: 118–122, 2003
Masticator myopathy
Authors: Yamada Shigeo , Ogawa Tomoko , Nishimiya Jin , Yuasa Tatsuhiko , Taketazu Fumitoshi
Published: June 2003

A 31‐year‐old woman developed low‐grade fever and pain and swelling of the masticatory muscles. A T2‐weighted magnetic resonance image showed high signal intensity in these muscles. Coxsackie B3 and echo 30 viruses were detected from a nasopharyngeal swab and feces, respectively. The clinical symptoms accompanied a marked decline in the serum immunoglobulin G level with progressive eosinophilia. Her symptoms disappeared by 8 weeks after onset. She was diagnosed as having masticator myopathy, which has rarely been reported in humans. The present case suggests that masticator myopathy is associated with coxsackie or echo virus infection. Muscle Nerve 28: 123–127, 2003
Novel missense mutation and large deletion of GNE gene in autosomal‐recessive inclusion‐body myopathy
Authors: Del Bo Roberto , Baron Pierluigi , Prelle Alessandro , Serafini Massimo , Moggio Maurizio , Fonzo Alessio Di , Castagni Marina , Bresolin Nereo , Comi Giacomo Pietro
Published: June 2003

The UDP‐N‐acetylglucosamine 2‐epimerase/N‐acetylmannosamine kinase (GNE) gene is the causative gene for autosomal‐recessive hereditary inclusion‐body myopathy (h‐IBM). Two sisters affected with autosomal‐recessive h‐IBM were shown to be compound heterozygous for two novel GNE mutations: a large deletion involving exons 1—9, and a R162C amino acid change in the epimerase domain. This is the first deletion event observed in a GNE allele and expands the molecular pathogenesis of autosomal‐recessive h‐IBM. Muscle Nerve 28: 113–117, 2003
Strength training alters the viscoelastic properties of tendons in elderly humans
Authors: Reeves Neil D. , Narici Marco V. , Maganaris Constantinos N.
Published: June 2003

The effect of strength training for 14 weeks on patella tendon viscoelastic properties was investigated in a group of elderly individuals. Participants were assigned to training (age [mean ± SD] 73.6 ± 3.4 years; n = 7) or control (age 66.4 ± 1.7 years; n = 7) groups. Training was performed three times per week and consisted of two series of 10 repetitions of leg‐extension and leg‐press exercises at 80% of the 5‐repetition maximum. Tendon elongation during an isometric knee‐extension contraction–relaxation was measured using ultrasonography. Tendon stiffness was calculated from the gradient of the estimated force–elongation relationship and mechanical hysteresis was calculated as the area between loading–unloading curves. Knee‐flexor coactivation, estimated from biceps femoris muscle electromyographic activity, was unaltered (P > 0.05) after the training and control periods. No changes (P > 0.05) were observed in stiffness or hysteresis after the control period. In contrast, tendon stiffness increased from 1376 ± 811 to 2256 ± 1476 N.mm−1 (P < 0.01) and hysteresis decreased from 33 ± 5 to 24 ± 4% (P < 0.05), after training. These training‐induced adaptations have implications for maximal muscle force, rate of force development, and metabolic cost of locomotion. Muscle Nerve 28: 74–81, 2003
Compressive lumbar myelopathy presenting as segmental motor neuron disease
Authors: Kleopa Kleopas A. , Zamba‐Papanicolaou Eleni , Kyriakides Theodoros
Published: June 2003

Four patients presented with slowly progressive, bilateral, asymmetric weakness and muscle atrophy in the lower extremities, accompanied by cramps and fasciculations. Sensory symptoms were insignificant. There was no bladder or bowel disturbance. Upper extremities and cranial nerves were normal. Weakness was found in lumbosacral myotomes, ranging from L2 to S1. The tendon reflexes varied, and extensor plantar responses were found in one case with proximal leg involvement. Nerve conduction studies were normal, but segmental chronic and often active denervation confined to the weak myotomes in the lower extremities was found in the electromyogram. Magnetic resonance imaging showed evidence of spondylotic lumbosacral myelopathy associated with disc herniation or osteophytic arthropathy at the T11/T12 spinal level in all patients, with increased signal within the adjacent cord. This unusual purely motor presentation may result from ischemic myelopathy secondary to compression of the anterior spinal artery. Muscle Nerve 28: 69–73, 2003
F‐wave acquisition using low‐current stimulation
Authors: DiBenedetto Margarete , Gale Shawn D. , Adarmes Demitri , Schabacker Michael
Published: June 2003

The purpose of this study was to assess the feasibility of utilizing low‐current stimulation for F‐wave generation, thereby avoiding the discomfort of repetitive supramaximal stimulation. We employed the same technique as is used for generating F waves in the conventional way, except for using a stimulating current that was just strong enough to evoke a motor response on the oscilloscope. This usually required a stimulus of about 10–15 mA at 0.2‐ms duration. Both median nerves of 30 subjects were evaluated with this technique and with F waves generated by the conventional technique in the same subjects. Amplitudes were larger when using supramaximal current stimulation. However, there was no statistical difference between F‐wave latencies, chronodispersion, and persistence (penetrance) elicited with maximal and low‐current stimulation. This procedure should represent a significant improvement for patient comfort during electrodiagnostic procedures involving F‐wave studies. Muscle Nerve 28: 82–86, 2003
Comparison between impairment and disability scales in immune‐mediated polyneuropathies
Authors: Merkies Ingemar S.J. , Schmitz Paul I.M. , van der Meché Frans G.A. , van Doorn Pieter A.
Published: June 2003

The ability of a scale to detect clinical relevant changes over time, i.e., its “responsiveness,” may help clinicians to choose among valid and reliable measures. Therefore, we investigated the responsiveness' rank ordering (best to worse) of six selected valid and reliable scales, namely the Medical Research Council (MRC)‐sumscore, sensory‐sumscore, grip‐strength (Vigorimeter), nine‐hole peg, ten‐meters walking, and a disability‐sumscore, in immune‐mediated polyneuropathies. Patients with newly diagnosed Guillain–Barré syndrome (n = 7) or chronic inflammatory demyelinating polyneuropathy (n = 13) were examined over 52 weeks. Responsiveness of each scale was measured using different methods (effect‐size, standardized response mean score, Wilcoxon matched‐pairs signed‐rank, and a newly devised Schmitz's distribution‐free responsiveness score), and the obtained scores in each method were plotted against the follow‐up period, thus allowing area‐under‐the‐curve calculations (higher area‐under‐the‐curve indicating better responsiveness). Also, longitudinal correlations were performed between the scales' values and patients' own clinical judgments (deteriorated, unchanged, improved) (higher correlation = better responsiveness). A consistent rank ordering was observed in each technique with the disability‐sumscore, MRC‐sumscore, and Vigorimeter being among the best responsive scales. Hence, the primary use of these measures is suggested in studies of immune‐mediated polyneuropathies. Muscle Nerve 28: 93–100, 2003
Electrospray mass spectrometric study of anionic complexes of enkephalins with Cu(II): regioselective distinction of Leu/Ile at the C‐terminus induced by metal reduction
Authors: Bossée Anne , Fournier Françoise , Tasseau Olivier , Bellier Bruno , Tabet Jean‐Claude
Published: June 2003

The yield of metallation of methionine‐enkephalin and leucine‐enkephalin isomers by copper(II) chloride was investigated by electrospray ionization ion trap mass spectrometry (ESI‐ITMS) in negative ionization mode. Binary ([(M3H)+CuII]−) and ternary ([(M2H)+CuIICl]−) complexes were observed. Soft and hard desolvation conditions (by changing the declustering voltage) were applied to study their influence on the metallation yield and on the observed deprotonated and metallated species. Structures of the binary complexes with defined charge locations are proposed, based on the observed in‐source fragmentations. It was demonstrated that the in‐source fragmentations under hard desolvation conditions could differentiate the Leu/Ile isomers if located at the C‐terminal position but not at the N‐terminal position. This behavior was also observed using a triple quadrupole analyzer. This facile distinction, due to a different radical loss from the [(M3HCO2)+CuII]− species (loss of [C3H7]. for YGGFL and [C2H5]. for YGGFI), was facilitated by the reduction of the oxidation state of Cu(II). This in‐source differentiation of YGGFI and YGGFL was also implemented in LC/ESI‐MS analysis by post‐column addition of the copper salt with a syringe pump. Copyright © 2003 John Wiley & Sons, Ltd.
Reconstruction of the isotopic history of animal diets by hair segmental analysis
Authors: Schwertl Michael , Auerswald Karl , Schnyder Hans
Published: June 2003

Carbon and nitrogen isotope signatures (δ13C and δ15N) of animal tissues provide information about the diet and, hence, the environment in which the animals are living. Hair is particularly useful as it provides a stable archive of temporal (e.g. seasonal) fluctuations in diet isotope composition. It can be sampled easily and with minimal disturbance from living subjects. However, derivation of the temporal record along the hair length may be subject to errors and uncertainties. This study investigates (and suggests means to minimize) several sources of error, including (a) incomplete sampling, (b) sampling during the quiescent (telogen) phase, (c) non‐representative sub‐sampling, (d) ignorance of hair growth rate, i.e. time–position relationship of isotope signatures, and (e) non‐optimal compromise between analytical/procedural precision and effort/cost. Cattle tail switch hair was collected from animals of different breed, sex and age. Hair was washed, sectioned, and 5‐ or 10‐mm‐long sections were analyzed for C and N isotope composition. Signatures along paired hairs were similar (r2 ≈ 0.8) and distances between isotopic minima and maxima nearly identical, indicating that a single hair constituted a representative sample and (except for telogen hair) hair growth rate was the same for paired hairs. However, cutting hair, instead of plucking, caused a variable loss of recently grown hair and information. Telogen hair was identified and data loss due to cutting error reduced when more than one hair from the same animal and sampling region was compared to spot and delimit common and missing regions. Similarly, comparison of isotopic profiles from hair collected at different times identified the segment produced during the respective interval and allowed calculation of average hair growth rate, which varied between animals (0.69–1.06 mm d−1). Analysis of alternate 10‐mm‐long sections for two hairs per animal provided a good compromise between precision/resolution and effort. The method should be applicable to other mammalian species including man. Copyright © 2003 John Wiley & Sons, Ltd.
Protein abundance quantification in embryonic stem cells using incomplete metabolic labelling with 15N amino acids, matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry, and analysis of relative isotopologue abundances of peptides
Authors: Vogt Josef A. , Schroer Klaus , Hölzer Kerstin , Hunzinger Christian , Klemm Martina , Biefang‐Arndt Katja , Schillo Simone , Cahill Michael A. , Schrattenholz André , Matthies Helmut , Stegmann Werner
Published: June 2003

An isotope dilution method for protein quantification is presented in the context of matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI‐TOFMS) and mass fingerprinting experiments, revealing an unappreciated high reproducibility and accuracy of relative peak intensity measurements. Labelled proteins were generated by growing cells in a medium containing 15N‐enriched amino acids, and were mixed with proteins of natural isotopic composition from control cells in ratios of approximately 0:1, 1:7, 1:2, 2:1, 7:1, and 1:0 (labelled/unlabelled). Mixtures were separated by two‐dimensional gel electrophoresis and analysed by MALDI‐TOFMS using typical experimental conditions. A linear relationship is demonstrated between the relative isotopologue abundances (RIA values) for particular peaks in the isotopic distribution of tryptic peptide fragments of the proteins, and the mole fractions of labelled proteins in the mixture. Analysis of RIA values (ARIA quantification) for peptides of six typical silver‐stained protein spots for the various mixtures could reproduce the experimentally contrived ratios with approximate errors between 4% (2:1 mixture) and about 18% (1:7 mixture). A consideration of error and its propagation is discussed. ARIA does not require complete separation of the isotope patterns of labelled and unlabelled peptides, and is therefore advantageous in combination with all kinds of labelling experiments in biological systems, because it is compatible with minimal metabolic incorporation of labelling reagent. Simulations indicate that the minimum required 15N enrichment of the total amino acid pool sufficient for ARIA is less than 4%. In an accompanying paper in this issue, we apply ARIA to proteins differentially labelled with isotope‐coded alkylation reagents. Copyright © 2003 John Wiley & Sons, Ltd.
Analysis of relative isotopologue abundances for quantitative profiling of complex protein mixtures labelled with the acrylamide/D3‐acrylamide alkylation tag system
Authors: Cahill Michael A. , Wozny Wojciech , Schwall Gerhard , Schroer Klaus , Hölzer Kerstin , Poznanovic Slobodan , Hunzinger Christian , Vogt Josef A. , Stegmann Werner , Matthies Helmut , Schrattenholz André
Published: June 2003

The new method of analysis of relative isotopologue abundances (ARIA) applied here is based on the evaluation of total isotope patterns of tryptic protein fragments measured by matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI‐TOFMS) to calculate the mixing ratios of composites consisting of stable isotope labelled and isotopically natural (unlabelled) proteins, as described in an accompanying paper in this issue. Recently, Sechi (Rapid Commun. Mass Spectrom. 2002; 16: 1416–1424) and Gehanne et al. (Rapid Commun. Mass Spectrom. 2002; 16: 1692–1698) introduced the use of differential quantitative mass analysis by MALDI‐TOFMS using mixtures of standard proteins alkylated prior to two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) with either acrylamide (AA) or deuterium‐labelled [2,3,3′‐D3]‐acrylamide (D3AA). In the present study we validate the AA/D3AA system, firstly by measuring the yield of proteins alkylated with AA, and secondly by using differential radioactive labels (125I and 131I) to quantitatively establish that non‐comigration in 2D‐PAGE is negligible. ARIA is then applied to quantitatively estimate the relative proportions of peptides labelled with AA or D3AA in the validated system, using typical silver‐stained 2D‐PAGE protein spots from 2D gels loaded with 150 μg of total liver protein. The precision and limitations of ARIA quantification of peptides differentially alkylated with isotopomeric reagents are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Preliminary study of the stability of calix[4]arene crown compounds under radiolysis
Authors: Jankowski C. K. , Allain F. , Dozol J. F. , Virelizier H. , Tabet J. C. , Moulin C. , Lamouroux C.
Published: June 2003

The extraction of 135Cs from high activity waste arising from reprocessing of spent fuel can be achieved by using calix[4]arene crown compounds. The radiolytic degradation of calix[4]arene crowns as well as their solvent, o‐nitrophenyloctyl ether (NPOE), was studied using electrospray ionization mass spectrometry (ESI‐MS) (that formed Cs+ or Na+ adducts) in nitric acid, as well as by chemical ionization tandem mass spectrometry (MS/MS) experiments. The structures of major degradation products were identified with MS and specifically labelled nitric acid. Although NPOE and calix[4]arene crowns alone are relatively stable, under simulated conditions resembling the real industrial processes involving radiolysis in the presence of nitric acid, several products resulting from nitration and oxidation were observed. Copyright © 2003 John Wiley & Sons, Ltd.
Nano‐high‐performance liquid chromatography in combination with nano‐electrospray ionization Fourier transform ion‐cyclotron resonance mass spectrometry for proteome analysis
Authors: Ihling Christian , Berger Kerstin , Höfliger Martin M. , Führer Dagmar , Beck‐Sickinger Annette G. , Sinz Andrea
Published: June 2003

Fourier transform ion‐cyclotron resonance (FTICR) mass spectrometry offers several advantages for the analysis of biological samples, including excellent mass resolution, ultra‐high mass measurement accuracy, high sensitivity, and wide mass range. We report the application of a nano‐HPLC system coupled to an FTICR mass spectrometer equipped with nanoelectrospray source (nano‐HPLC/nano‐ESI‐FTICRMS) for proteome analysis. Protein identification in proteomics is usually conducted by accurately determining peptide masses resulting from enzymatic protein digests and comparing them with theoretically digested protein sequences from databases. A tryptic in‐solution digest of bovine serum albumin was used to optimize experimental conditions and data processing. Spots from Coomassie Blue and silver‐stained two‐dimensional (2D) gels of human thyroid tissue were excised, in‐gel digested with trypsin, and subsequently analyzed by nano‐HPLC/nano‐ESI‐FTICRMS. Additionally, we analyzed 1D‐gel bands of membrane preparations of COS‐6 cells from African green monkey kidney as an example of more complex protein mixtures. Nano‐HPLC was performed using 1‐mm reverse‐phase C‐18 columns for pre‐concentration of the samples and reverse‐phase C‐18 capillary columns for separation, applying water/acetonitrile gradient elution conditions at flow rates of 200 nL/min. Mass measurement accuracies smaller than 3 ppm were routinely obtained. Different methods for processing the raw data were compared in order to identify a maximum number of peptides with the highest possible degree of automation. Parallel identification of proteins from complex mixtures down to low‐femtomole levels makes nano‐HPLC/nano‐ESI‐FTICRMS an attractive approach for proteome analysis. Copyright © 2003 John Wiley & Sons, Ltd.
Identification of phytoestrogens in bovine milk using liquid chromatography/electrospray tandem mass spectrometry
Authors: Antignac Jean‐Philippe , Cariou Ronan , Le Bizec Bruno , Cravedi Jean‐Pierre , Andre François
Published: June 2003

In an international context of promoting scientific research on food safety, the interest in molecules having potential hormonal disrupting effects is growing. While industrial endocrine disruptors (phthalates, alkylphenols, PCBs, etc.) have been studied for several years, natural compounds like phytoestrogens remain less investigated. Accordingly, a research project was initiated with its main objectives to develop efficient analytical methods for a wide range of phytoestrogens in various food matrices, and to evaluate their occurrence in food products. Electrospray ionization with tandem mass spectrometric (MS/MS) analysis of isoflavones (genistein, daidzein, equol, formononetin, biochanin A), lignans (enterolactone, enterodiol), and coumestans (coumestrol) was investigated. This study revealed the formation of a large number of fragment ions in both positive and negative modes, corresponding to specific cleavages of the hydroxyl, carbonyl, and/or methoxy groups, and to Retro‐Diels‐Alder reactions. An LC/ESI‐MS/MS method was developed consistent with the 2002/657/EC European decision criteria. An extraction and clean‐up method was developed for milk samples. The identification limit for the proposed method appears to be under 1 ng/mL. The developed methodology was applied to various milk samples, and the occurrence of isoflavones (particularly equol) was demonstrated in the concentration range 1–30 ng/mL. The efficiency of the proposed analytical method permitted evaluation of a new and promising approach to a global risk assessment of natural estrogenic active substances including phytoestrogens and their metabolites. Copyright © 2003 John Wiley & Sons, Ltd.
ESI‐MS/MS analysis of underivatised amino acids: a new tool for the diagnosis of inherited disorders of amino acid metabolism. Fragmentation study of 79 molecules of biological interest in positive and negative ionisation mode
Authors: Piraud Monique , Vianey‐Saban Christine , Petritis Konstantinos , Elfakir Claire , Steghens Jean‐Paul , Morla Aymeric , Bouchu Denis
Published: June 2003

The diagnosis of inherited disorders of amino acids (AA) metabolism is usually performed on automated analysers by ion‐exchange chromatography and quantification after ninhydrin derivatisation of about 50 different AA. A single run liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for these molecules can be an alternative to this time‐consuming technique. The first step of this development is the infusion study of the fragmentation of 79 molecules of biological interest in electrospray ionisation tandem mass spectrometry (ESI‐MS/MS), in positive and in negative ionisation mode. Among them, three molecules can be detected only in negative ionisation mode, 38 only in positive mode and 38 in the two modes. All the most abundant fragmentations are presented, with optimisation of the MS/MS parameters. The positive ionisation mode was retained for the simultaneous analysis of 76 molecules. One sensitive and/or specific transition is proposed for the monitoring of each molecule. Improvement in sensitivity of detection was obtained with the use of an acidic mobile phase. Flow injection analysis studies led us to highlight a number of interferences—due to isobaric molecules, to in‐source collision‐induced dissociation, or to natural isotopic distribution of the elements—which are listed. For a reliable quantification method, these molecules have to be separated by LC before analysis in the tandem mass spectrometer. Ion‐pairing reversed‐phase liquid chromatography (RPLC) using perfluorinated carboxylic acids as ion‐pairing agents has already been found suitable for analysis of AA in MS/MS positive ionisation mode and is under development. Copyright © 2003 John Wiley & Sons, Ltd.
Fast high‐precision on‐line determination of hydrogen isotope ratios of water or ice by continuous‐flow isotope ratio mass spectrometry
Authors: Huber C. , Leuenberger M.
Published: June 2003

A new fast high‐precision on‐line technique is described for the determination of hydrogen isotope ratios of water by continuous‐flow mass spectrometry. For the first time H2/H2O‐equilibration using a platinum catalyst has been used in a fully continuous process. A significant reduction in the H2/H2O‐equilibration time is achieved by a complete vaporization of the water and by increasing the exchange temperature to 100°C. The analysis time is only ∼5 min/sample which includes equilibration and processing. Measurement precision and accuracy are better than 1‰ and sample consumption is only ∼5 μL. This new technique allows the measurement of a wide range of aqueous samples either in a semi‐continuous way (discrete samples are injected one after another) or in a fully continuous way. This allows us, for the first time, to make continuous measurements of ice cores. Copyright © 2003 John Wiley & Sons, Ltd.
Wave theory of x‐ray scattering in capillary structures
Authors: Dabagov S. B.
Published: June 2003

Recently, several coherent phenomena associated with the propagation of x‐rays in capillary optical elements (polycapillary lenses and systems of capillaries) have been observed. In order to describe these effects, a quantum‐wave theory of channeling was developed. In this paper, a theoretical analysis of scattering of x‐rays in capillary micro‐ and nanostructures within the frame of the wave approach is presented. Copyright © 2003 John Wiley & Sons, Ltd.
Review of capillary x‐ray optics from the 2nd International Capillary Optics Meeting
Authors: Bilderback Donald H.
Published: June 2003

The 2nd International Capillary Optics Meeting (ICOM2001) took place at the University of Antwerp, 17–21 June 2001. One of the meeting aims was to provide a forum to review the progress in x‐ray optics made from monocapillaries, polycapillaries and waveguides. These optics are often employed to better match the properties of a tube or synchrotron x‐ray source to x‐ray applications such as diffraction, fluorescence, spectroscopy, etc. Many of the applications involve small beams on the size scale from 30 nm to 50µm. The focus on the initial capillary optics meeting 5 years ago at Cornell University was on how to make and characterize optics. At this meeting, however, the highlights were more centered on how to use optics in interesting applications. Steady progress has been made in the manufacture of higher performance optics and this improvement in technical performance is continuing to drive the interest in commercialization and utilization of these novel forms of x‐ray optics in many areas of science and technology. This paper gives a brief overview of the meeting presentations and also describes some of the recent progress in capillary optics manufacture and application at CHESS at Cornell University. Copyright © 2003 John Wiley & Sons, Ltd.
Examination of poly‐capillary lenses for their use in micro‐XRF spectrometers
Authors: Haschke M. , Haller M.
Published: June 2003

The availability of poly‐capillary lenses opens up a wide variety of possibilities for the analysis of small sample areas because a large part of the tube radiation can captured and focused on the sample. Propagation in the glass capillaries is achieved by external total reflection on their internal surface. At first the intensity gain of the lenses and their spot size were the most interesting parameters. However, by using these lenses in commercial instruments, other parameters became more important for characterizing their performance for spectroscopic use, e.g. the energy dependence of the spot size and of the transmission efficiency and their influence to the tube spectrum. In this paper, the examination of various lenses from different manufacturers is described. It is shown that for the main parameters spot size and intensity gain, the differences are negligible. However, other parameters can be influenced by the change in geometric parameters of the lens such as the diameter of the single capillaries and bending radius of the lenses. These changes need high perfection in lens manufacturing. It seems that at present only one of the manufacturers is able to control the process in this way. However, there is also another requirement for the implementation of lenses for commercial instruments, namely the uniformity of the outer dimensions. Only in this case can these components be used without special adaptation in a routine instrument. This also requires the complete control of the manufacturing process. Because the use of poly‐capillary lenses is in its early stages, it seems necessary to define more exactly the parameters that characterize the x‐ray optical components. Only in this case will it be possible to define the performance of the optics with high precision and compare lenses from different manufacturers. Copyright © 2003 John Wiley & Sons, Ltd.
Metal capillary optics: novel fabrication methods and characterization
Authors: Hirsch Gregory
Published: June 2003

A method for manufacturing metal monocapillary optics is described. The fabrication process begins by withdrawing an initially uniform wire from an etchant bath at a variable rate using a computer‐controlled translation stage. This generates a precise taper profile on the wire that corresponds to the bore of a capillary that will be produced in subsequent steps. Paraboloidal, ellipsoidal or other capillary figures can be programmed into the motion controller. Two different methods are discussed for generating the completed optic from the etched wire. In both of these techniques, the wire functions as an expendable mandrel. In the first method, the wire is first coated with a radiation‐reflecting material and then bonded to a rigid substrate. The wire is then dissolved using a chemical process to produce the hollow capillary optic. In the second method, a purely mechanical process imprints the wire figure into a softer material to create the capillary optic. Both manufacturing processes permit the production of capillaries that are accurately figured, extremely straight and have very low surface roughness. Wide latitude is possible in the selection of reflective materials that coat the internal surface of the optics. Experimental measurements using the optics with synchrotron radiation have demonstrated 5–10 µm diameter beams having flux‐density gains near 100. Potential improvements to the capillaries for achieving higher gains and smaller sizes are discussed. In addition to synchrotron radiation experiments, applications with small laboratory instruments are considered. The ultimate limitations of the optics and their comparison with glass capillaries are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Peatland responses to varying interannual moisture conditions as measured by automatic CO2 chambers
Authors: Bubier Jill , Crill Patrick , Mosedale Andrew , Frolking Steve , Linder Ernst
Published: June 2003

Net ecosystem CO2 exchange (NEE) was measured from June 2000 through October 2001 by 10 automatic chambers at a peatland in southeastern New Hampshire. The high temporal frequency of this sampling method permitted detailed examination of NEE as it varied daily and seasonally. Summer of 2001 was significantly drier than the 30‐year average, while summer of 2000 was wetter than normal. Although NEE varied spatially across the peatland with differences in plant species composition and biomass, maximum CO2 uptake was 30–40% larger in the drier summer in evergreen and deciduous shrub communities but the same or lower in sedge sites. Ecosystem respiration rates were 13–84% larger in the drier summer depending on plant growth form with water table and temperature as strong predictors. Ecosystem respiration was also correlated with maximum ecosystem productivity and foliar biomass suggesting that plant processes, water table, and temperature are tightly linked in their control of respiratory losses. The ratio between maximum productivity and respiration declined for evergreen shrub and sedge sites between the wet and dry summer, but increased in deciduous shrub sites. A drier climate may reduce the CO2 sink function of peatlands for some growth forms and increase it for others, suggesting that ecosystem carbon and climate models should account for differences in growth form responses to climate change. It also implies that plant functional types respond on short timescales to changes in moisture, and that the transition from sedges to shrubs could occur rapidly in peatlands under a drier and warmer climate.
Global magnetospheric‐ionospheric oscillations initiated by a solar wind pressure impulse
Authors: Huang Chao‐Song , Foster J. C. , Reeves G. D. , Watermann J. , Sastri J. H. , Yumoto K. , Song P.
Published: June 2003

We present simultaneous observations of long‐period (∼1 hour) global magnetospheric‐ionospheric oscillations with multiple spacecraft and ground‐based instruments. These oscillations occurred following a major increase in the solar wind dynamic pressure. When the solar wind pressure impulse impinged on the magnetosphere, oscillations of energetic plasma particles in the ring current region were excited. The strongest oscillations came from electrons in the energy range of 75–225 keV with periods of 55–80 min. Ground magnetometers measured periodic (∼1 hour) enhancements of ionospheric currents from the auroral to equatorial latitudes. However, the solar wind pressure and IMF in this event did not show variations similar to the energetic particle oscillations and/or ground magnetometer deviations. We suggest that the magnetosphere has an intrinsic period of ∼1 hour during quiet times. The magnetospheric oscillations with this period can be initiated by a solar wind pressure impulse. After the initiation the solar wind no longer plays a role in the subsequent evolution of the magnetospheric oscillations.
Variability of Arctic and North Atlantic sea ice: A combined analysis of model results and observations from 1978 to 2001
Authors: Kauker Frank , Gerdes Rüdiger , Karcher Michael , Köberle Cornelia , Lieser Jan L.
Published: June 2003

Ice cover data simulated by a coupled sea ice‐ocean model of the North Atlantic and the Arctic Ocean are compared with satellite observations for the period 1978–2001. The capability of the model in reproducing the long‐term mean state and the interseasonal variability is demonstrated. The main modes of variability of the satellite data and the simulation in the summer and winter half years are highly similar. Using NCEP/NCAR reanalysis data and the results from the sea ice‐ocean model, we describe the relationship with atmospheric and oceanic variables for the first two modes of sea ice concentration variability in winter and in summer. The first winter mode shows a time‐delayed response to the Arctic Oscillation due to advection of heat anomalies in the ocean. The second winter mode is dominated by an event in the late 1990s that is characterized by anomalously high pressure over the eastern Arctic. The first summer mode is strongly influenced by the Arctic Oscillation of the previous winter. The second summer mode is caused by anomalous air temperature in the Arctic. This mode shows a distinctive trend and is related to an ice extent reduction of about 4 · 105 km2 over the 23 years of analysis.
Generation of recent massive water floods at Cerberus Fossae, Mars by dike emplacement, cryospheric cracking, and confined aquifer groundwater release
Authors: Head James W. , Wilson Lionel , Mitchell Karl L.
Published: June 2003

Previous studies noted the close association of geologically very recent lava flows and fluvial channels emanating from Cerberus Fossae. To assess these relationships, we outline a model of magmatic dike emplacement that involves 1) surface fractures and localized volcanic eruptions, 2) attendant cryospheric cracking to fracture the surface and release pressurized groundwater confined beneath the cryosphere, 3) effusion of water along a segment of the fracture to form Athabasca Valles, and 4) heating of the regions adjacent to the dike to cause melting and subsequent subsidence of the surface, forming late‐stage pits and depressions. Previous estimates of the aqueous discharge were ∼1–2 × 106 m3 s −1. Our models show that this flux could be readily accommodated by flow through adjacent dike‐related cryospheric fractures at water rise speeds of ∼60 m/s. The required aquifer permeability, however, is far larger than commonly encountered over similar depths and scales on Earth. This suggests that water may be transported in the subsurface by mechanism more efficient than porous flow, and/or that the previously proposed volume flux values are overestimates.
Effects of angiogenic regulators on in vitro proliferation and cytokine secretion by native human acute myelogenous leukemia blasts
Authors: Bruserud Øystein , Glenjen Nils , Ryningen Anita
Published: June 2003

Abstract: Angiogenesis seems to be important in the pathogenesis of acute myelogenous leukemia (AML). The endothelial cell proliferation and microvessel formation are regulated by a wide range of soluble mediators, including angiogenin, angiopoietin‐2, basic fibroblast growth factors, vascular endothelial growth factor (VEGF), VEGF‐D, angiostatin and endostatin. In the present study, it has been investigated whether these mediators have an additional direct effect on the proliferation and cytokine release by native human AML blasts. AML cells derived from a large group of consecutive patients were investigated. All these mediators could alter the proliferation and cytokine release [interleukin (IL) 1β, IL6, IL8, tumor necrosis factor α] for a minority of patients. Alteration of spontaneous proliferation by at least one mediator was detected in five of 38 patients; whereas, altered cytokine (Flt3‐ligand, granulocyte‐macrophage colony‐stimulating factor, stem cell factor)‐dependant proliferation was observed for 10 patients. Growth enhancement was most frequently observed, whereas growth inhibition was uncommon. The effects on AML blast proliferation were often dependant on or were modulated by the presence of the three hematopoietic growth factors. Based on the present results, it is concluded that angioregulatory mediators have additional growth‐enhancing effects directly on the AML blasts for certain patients. However, based on the results from this investigation and previous studies it is suggested that their major contribution to the pathogenesis of AML is through their effects on regulation of bone marrow angiogenesis, and future studies of these mediators in AML should probably focus on these effects.
Analysis of natural killer (NK) cell activity and adhesion molecules on NK cells from umbilical cord blood
Authors: Tanaka Hidehisa , Kai Shunro , Yamaguchi Masao , Misawa Mahito , Fujimori Yoshihiro , Yamamoto Masuji , Hara Hiroshi
Published: June 2003

Abstract: The activity of natural killer (NK) cells in human umbilical cord blood (CB) has been reported to be low, compared with that in adult peripheral blood (PB) in vitro. To examine the cause of this, after dividing the CD56+/CD3− cells in CB and PB into CD56bright and CD56dim NK cells, the NK cell activities and the expression of various surface antigens were assayed for each fraction. The NK cell activity of CD56dim NK cells in CB was significantly lower than that in PB (P = 0.0003), whereas, there was no significant difference between the NK cell activity of CD56bright NK cells in PB and CB. The expression levels of adhesion molecules (CD2, CD11a, CD18, DNAX accessory molecule‐1), CD16, and CD57 for CD56dim NK cells in CB were significantly lower than those in PB, and approximately one‐third of CB CD56dim NK cells were capable of forming conjugates with K562 cells, compared with PB CD56dim NK cells. Furthermore, the inhibition of both the NK cell activities and binding of CD56dim NK cells in PB and CB by monoclonal antibody against each of these adhesion molecules suggests that they play an important role in NK cell activity. These findings show that the low NK cell activity in CB is caused by the low NK cell activity of CD56dim NK cells and that the low expression level of adhesion molecules on CB CD56dim NK cells may contribute to this low NK cell activity.