bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cellular and molecular mechanisms leading to cortical reaction and polyspermy block in mammalian eggs
Authors: Sun Qing‐Yuan 
Published: June 2003

AbstractFollowing fusion of sperm and egg, the contents of cortical granules (CG), a kind of special organelle in the egg, release into the perivitelline space (cortical reaction), causing the zona pellucida to become refractory to sperm binding and penetration (zona reaction). Accumulating evidence demonstrates that mammalian cortical reaction is probably mediated by activation of the inositol phosphate (PIP2) cascade. The sperm‐egg fusion, mediated by GTP‐binding protein (G‐protein), may elicit the generation of two second messengers, inositol 1,4,5 triphosphate (IP3) and diacylglycerol (DAG). The former induces Ca2+ release from intracellular stores and the latter activates protein kinase C (PKC), leading to CG exocytosis. Calmodulin‐dependent kinase II (CaMKII) may act as a switch in the transduction of the calcium signal. The CG exudates cause zona sperm receptor modification and zona hardening, and thus block polyspermic penetration. Oolemma modification after sperm‐egg fusion and formation of CG envelope following cortical reaction also contribute to polyspermy block. Microsc. Res. Tech. 61:342–348, 2003. © 2003 Wiley‐Liss, Inc.
Fertilization abnormalities following human in vitro fertilization and intracytoplasmic sperm injection
Authors: Feng H. , Hershlag A. 
Published: June 2003

AbstractFertilization abnormalities are commonly encountered following in vitro fertilization. The widespread introduction of assisted fertilization methods has rapidly led to a changes in both the incidence and types of these aberrations. Such abnormalities can be identified by careful morphological evaluation at the early zygote stage, of pronuclei as well as of polar body formation, and may be confirmed by cytogenetic assessment. The recognition and understanding of fertilization abnormalities have led to the development of novel techniques aimed at preventing them, as well as recent bold attempts at correction. Removal of one pronucleus may allow some triploid embryos to revert to a normal diploid stage. These new developments should provide insight into the understanding of parthenogenesis, androgenesis, and gynogenesis in the human. Microsc. Res. Tech. 61:358–361, 2003. © 2003 Wiley‐Liss, Inc.
Sphincter electromyography and multiple system atrophy
Authors: Nahm Frederick , Freeman Roy 
Published: June 2003

AbstractElectromyographic studies of the sphincter in patients with multiple system atrophy have shown increased duration and polyphasia of motor unit potentials. These electrophysiological markers have been used to argue for the selective degeneration of sacral motor neurons in Onuf's nucleus in patients with multiple system atrophy. Studies comparing sphincter electromyographic changes in patients with multiple system atrophy and Parkinson's disease have shown significant differences between these two patient populations. Despite the controversy surrounding this claim, recent studies using quantitative electromyographic techniques support the view that reinnervation of the anal sphincter muscles may be a useful diagnostic marker for distinguishing multiple system atrophy from Parkinson's disease. A critical review of these data is needed to assess the validity and reliability of electromyographic changes in multiple system atrophy. © 2003 Wiley Periodicals, Inc. Muscle Nerve 28: 18–26, 2003
Knee extensor torque, work, and EMG during subjectively graded dynamic contractions
Authors: Pincivero Danny M. , Dixon Paul T. , Coelho Alan J. 
Published: June 2003

AbstractWe examined knee extensor peak torque, work, and electromyogram (EMG) during dynamic contractions to perceived exertion levels in men and women. Thirty subjects performed three maximal effort isokinetic knee extensions (60 deg.s−1), followed by three contractions to each of nine separate levels of perceived exertion. Surface EMG of the vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF), and knee extensor peak torque and work were normalized to a percent of each respective value obtained during the maximal effort contractions. The results demonstrated a significant linear increase in voluntary knee extensor peak torque and work across perceived exertion levels. Knee extensor peak torque and work were less than 70%, 80%, and 90% maximal voluntary contraction (MVC) at perceived exertion levels 7, 8, and 9, respectively. A significant increase in VM, VL, and RF muscle EMG was observed across perceived exertion levels 1 through 9, with EMG increase highest for the VL. The findings demonstrate that dynamic contractions guided by perceived exertion are underproduced at relatively high perceptual intensities, and that reliance on VL activation occurs across submaximal torque levels. The overestimation of knee extensor peak torque and work at relatively high perceptual intensities may suggest the presence of a subconscious mechanism aiming to reduce high muscle and joint forces. Muscle Nerve 28: 54–61, 2003
Ethical review of research involving human subjects: When and why is IRB review necessary?
Authors: Wagner Richard M. 
Published: June 2003

AbstractRequirements for ethical review of research involving human subjects are based on widely accepted international standards that are implemented by various national regulations and institutional policies. In the United States, most human research is reviewed by institutional review boards (IRBs) applying federal standards. Researchers may not realize the variety of studies that should be submitted for review. Studies involving interventions must be reviewed regardless of whether these are standard interventions, nonmedical interventions, or retrospective studies. Quality improvement activities require IRB review if the results may be published. Research use of information from medical records or of biomedical specimens requires review unless no identifiers are recorded. Review must be sought at least annually and whenever the research changes. Even human research that is technically exempt from Federal regulations usually needs to have that exemption certified by someone other than the researcher. Muscle Nerve 28: 27–39, 2003
Analysis of high mass peptides using a novel matrix‐assisted laser desorption/ionisation quadrupole ion trap time‐of‐flight mass spectrometer
Authors: Martin Rachel L. , Brancia Francesco L. 
Published: June 2003

AbstractA novel matrix‐assisted laser desorption/ionisation quadrupole ion trap time‐of‐flight (MALDI QIT ToF) mass spectrometer has been used to analyse high mass peptide ions exceeding 2000 Da. Human adrenocorticotropic hormone (fragment 18–39) and oxidised bovine insulin chain B were utilised to evaluate the performance of the instrument both in MS and in MS/MS mode. Its ability to efficiently isolate ions and to fragment them using collisionally activated decomposition (CAD) has been demonstrated using mixtures diluted to the low‐femtomole level on target. Additionally, multiple stage mass spectrometry (MS/MS/MS) provides a second‐generation product ion spectrum in which new fragment ions are detected and new stretches of amino acids are identified. Copyright © 2003 John Wiley & Sons, Ltd.
Cluster chemical ionization for improved confidence level in sample identification by gas chromatography/mass spectrometry
Authors: Fialkov Alexander B. , Amirav Aviv 
Published: June 2003

AbstractUpon the supersonic expansion of helium mixed with vapor from an organic solvent (e.g. methanol), various clusters of the solvent with the sample molecules can be formed. As a result of 70 eV electron ionization of these clusters, cluster chemical ionization (cluster CI) mass spectra are obtained. These spectra are characterized by the combination of EI mass spectra of vibrationally cold molecules in the supersonic molecular beam (cold EI) with CI‐like appearance of abundant protonated molecules, together with satellite peaks corresponding to protonated or non‐protonated clusters of sample compounds with 1–3 solvent molecules. Like CI, cluster CI preferably occurs for polar compounds with high proton affinity. However, in contrast to conventional CI, for non‐polar compounds or those with reduced proton affinity the cluster CI mass spectrum converges to that of cold EI. The appearance of a protonated molecule and its solvent cluster peaks, plus the lack of protonation and cluster satellites for prominent EI fragments, enable the unambiguous identification of the molecular ion. In turn, the insertion of the proper molecular ion into the NIST library search of the cold EI mass spectra eliminates those candidates with incorrect molecular mass and thus significantly increases the confidence level in sample identification. Furthermore, molecular mass identification is of prime importance for the analysis of unknown compounds that are absent in the library. Examples are given with emphasis on the cluster CI analysis of carbamate pesticides, high explosives and unknown samples, to demonstrate the usefulness of Supersonic GC/MS (GC/MS with supersonic molecular beam) in the analysis of these thermally labile compounds. Cluster CI is shown to be a practical ionization method, due to its ease‐of‐use and fast instrumental conversion between EI and cluster CI, which involves the opening of only one valve located at the make‐up gas path. The ease‐of‐use of cluster CI is analogous to that of liquid CI in ion traps with internal ionization, and is in marked contrast to that of CI with most other standard GC/MS systems that require a change of the ion source. Copyright © 2003 John Wiley & Sons, Ltd.
Quantification of isoflavones and lignans in serum using isotope dilution liquid chromatography/tandem mass spectrometry
Authors: Grace Philip B. , Taylor James I. , Botting Nigel P. , Fryatt Tara , Oldfield Mark F. , Al‐Maharik Nawaf , Bingham Sheila A. 
Published: June 2003

AbstractPhytoestrogens (isoflavones and lignans) are receiving increasing attention due to a potential protective effect against a number of complex diseases. However, in order to investigate these associations, it is necessary to accurately quantify the levels of phytoestrogens in foods and biological fluids. We report an assay for three isoflavones (daidzein, genistein, and glycitein), two metabolites of daidzein (O‐desmethylangolensin and equol), and two lignans (enterodiol and enterolactone) in human serum using electrospray ionisation liquid chromatography/mass spectrometry (LC/MS) with selective reaction monitoring. A simple, highly automated sample preparation procedure requires only 200 μL of sample and utilises one solid‐phase extraction stage. Limits of detection are in the region of 10 pg/mL for all analytes except equol, which had a limit of detection of approximately 100 pg/mL. The method developed is suitable for measuring the concentrations of phytoestrogens in blood samples collected from large epidemiological studies. The results of the analysis of serum samples from 300 men and women living in the UK are reported. Copyright © 2003 John Wiley & Sons, Ltd.
Status and perspectives of capillary optics at a third‐generation synchrotron radiation source
Authors: Vincze L. , Riekel C. 
Published: June 2003

AbstractGlass capillary optics has been used routinely at the ESRF microfocus beamline for several years. A large fraction of applications has been to solid polymers and biopolymers. Flux densities up to 108 photons s−1µm−2 mA−1 at 13 keV have been obtained for a beam size down to 2 µm fwb (full‐width‐at‐base). By better matching the divergence from the condensing mirror system to the acceptance of the capillary and increasing the brilliance by an undulator optimized to 13 keV, the flux density is expected to increase by up to a factor of 100. A reduction of beam size to about 100 nm by maintaining current flux density levels is in principle possible. Copyright © 2003 John Wiley & Sons, Ltd.
Characterization of a polycapillary lens for use in micro‐XANES experiments
Authors: Proost K. , Vincze L. , Janssens K. , Gao N. , Bulska E. , Schreiner M. , Falkenberg G. 
Published: June 2003

AbstractPolycapillary lenses permit x‐rays to be focused down to relatively small (<50 µm) beam diameters. A polycapillary device, suitable for focusing of synchrotron radiation, was characterized at beam line L of HASYLAB (Hamburg, Germany). Beam parameters such as beam size, transmission efficiency and gain in flux density were determined as a function of the energy of the primary monochromatic beam entering the polycapillary. At a distance of 4 mm between the lens tip and the sample, the smallest beam diameters were recorded: 30 µm at 7 keV, decreasing to 8 µm at 21 keV. In the energy range from 7 to 15 keV, the transmission efficiency varied between 30 and 45%, while the maximum gain in flux density was calculated to be around 3500. When the energy was changed from 7 to 30 keV, a vertical translation of only 7–8 µm was observed, indicating that this optic is highly suitable for use in µ‐XANES investigations. To illustrate this point, the investigation of paper corrosion due to iron gall inks and the speciation of Ni in environmental particles is described. Copyright © 2003 John Wiley & Sons, Ltd.
Interference and diffraction in capillary x‐ray optics
Authors: Kukhlevsky S. V. 
Published: June 2003

AbstractThe optical guiding of x‐ray radiation by capillary waveguides is analysed by using the Fresnel–Kirchhoff diffraction theory and the method of images. The guiding of the continuous, short‐pulse, coherent, partially coherent and incoherent waves is presented as the diffraction and interference of several x‐ray beams produced in free space by the Fresnel source of the waveguide. Using the Fresnel source properties, the necessary conditions for influence of the diffraction and interference on the output characteristics of the capillary x‐ray optics in the near‐ and far‐field diffraction zones are derived. The experimental data and computer simulations presented confirm the wave optics behaviour of x‐rays under such conditions. Copyright © 2003 John Wiley & Sons, Ltd.
Reconstruction of the three‐dimensional distribution of elements in fly‐ash particles by micro‐XRF spectroscopy
Authors: Rindby Anders , Janssens Koen , Osan Janos 
Published: June 2003

AbstractWith the very large information depth available in micro‐beam XRF, it is possible to generate two‐dimensional maps of the elemental distribution over large spherical fly‐ash particles with a resolution down to about 1 µm. These particles possess a large degree of spherical symmetry owing to the process of their formation. By applying special reconstruction algorithms, the symmetric part of the elemental distribution can be reconstructed from the two‐dimensional projection maps and subtracted from the original map. The results show that such a fly‐ash particle can be split into a radial symmetric part containing non‐volatile carbonaceous compounds and an asymmetric part representing precipitates or sub‐particles formed within the fly‐ash particle. The symmetric part shows a distinctly visible outer and an inner shell. By using the asymmetric part of the distribution, the interior of the fly‐ash particle can be studied without interference from the inner and outer shells. Copyright © 2003 John Wiley & Sons, Ltd.
Chronic basophilic leukemia: a distinct clinico‐pathologic entity?
Authors: Pardanani Animesh D. , Morice William G. , Hoyer James D. , Tefferi Ayalew 
Published: June 2003

Abstract: Objective: We sought to better define a group of rare and poorly understood myeloproliferative disorders that are characterized by prominent chronic basophilia in the absence of the Philadelphia chromosome (Ph) or its molecular equivalent.Methods: We screened our institution's electronic database from 1975 onwards, and identified four such cases. Clinical data and bone marrow pathology were carefully reviewed for these patients.Results: Two patients had prominent manifestations of basophil mediator‐release and another presented with pituitary dysfunction. Bone marrow examination uniformly revealed trilineage hyperplasia with basophilia and eosinophilia, dysplastic megakaryocytic hyperplasia, and the absence of megakaryocyte clustering. An abnormal pattern of atypical mast cells was noted in two cases. While disease palliation was effectively achieved with hydroxyurea for one patient, transformation to acute myeloid leukemia was eventually observed in this case. Another patient has achieved long‐term disease‐free survival after undergoing allogeneic stem cell transplantation.Conclusions: Our observations reveal a striking pathologic similarity among all four cases, and suggest this disease, which may be aggressive with the potential to transform into acute leukemia, to possibly represent a distinct clinico‐pathologic entity (chronic basophilic leukemia).
Fludarabine plus cyclophosphamide for the treatment of advanced chronic lymphocytic leukemia
Authors: Schiavone Ettore Mariano , De Simone Mariacarla , Palmieri Salvatore , Annunziata Mario , Pocali Barbara , Copia Carolina , D'Amico Maria Rosaria , Vecchio Luigi Del , Ferrara Felicetto 
Published: June 2003

Abstract:Objectives:Therapeutic results in advanced chronic lymphocytic leukemia (CLL) are still unsatisfactory in terms of complete remission achievement and duration, in spite of the extensive use of purine analogs. The objective of this study was to describe the clinical characteristics and treatment results from a series of 32 patients managed with a therapeutic program based on the combination of fludarabine and cyclophosphamide (CTX).Methods:Thirty‐two patients (median age 63 yr, range 42–75 yr) with newly diagnosed (47%) or refractory‐relapsed (53%) CLL were programmed to receive six courses of a 3‐d combination of fludarabine at 30 mg/m2/d plus CTX at 300 mg/m2/d. Refractory‐relapsed patients had previously received different chemotherapy lines from 1 to 5.Results:Fourteen of 32 (44%) patients achieved a complete remission, 16 (50%) obtained partial remission and two (6%) failed to respond. The CR rate was higher in untreated patients; in particular, CR was achieved in nine of 15 (60%) newly diagnosed cases as opposed to five of 17 (29%) among pretreated patients. Toxicity was caused by myelosuppression and/or infections in most cases. After a median follow‐up of 24 months (range 8–48 months), 20 of 32 patients (62%) are alive, and 14 of 32 (44%) are free from progression. Median overall survival and median time to progression were 35 and 25 months, respectively.Conclusion:The combination of fludarabine with CTX is effective in advanced CLL with acceptable toxicity, either as first‐line therapy or in refractory‐relapsed patients. In particular, a considerable rate of complete remission can be achieved in untreated patients. Myelosuppression represents the major side‐effect.
Antitumor effect of new local hyperthermia using dextran magnetite complex in hamster tongue carcinoma
Authors: Wada S , Tazawa K , Furuta I , Nagae H 
Published: June 2003

OBJECTIVE: This study was performed to clarify the usefulness of Dextran magnetite (DM) for the oral cancer hyperthermia. METHODS: Tumors were induced in golden hamster tongue by 9,10‐dimethyl 1‐1,2‐benzanthracene (DMBA) application. DM suspension was locally injected into the tumor‐bearing tongue and tongues were heated up to 43.0–45.0°C, by AC magnetic field of 500 kHz. RESULTS: The average time taken for the temperature to rise to 43.0°C or above was 162 s (n = 17) at the margin of the tumor and 420 s (n = 17) at the center of the tumor. According to the tumor volume, the time required for an increase in the central temperature of tumor to 43.0°C tended to be prolonged. Both temperatures could be maintained at approximately 43.0–45.0°C for 30 min. The inhibition of the growth of tongue carcinoma in the four‐time heating group was significantly greater than in the control group (P < 0.01). Moreover, the survival rate was significantly higher in the heated groups than in the control group (P < 0.01). Histological examination revealed a brown uniform DM accumulation at the stroma in the margin of the tumors. Many of tumor cells disappeared at the site adjacent to this accumulation. CONCLUSION: These results strongly suggest the usefulness of this local hyperthermic system in the oral region that is accessible to this treatment.
Oral health condition in southern Chinese after radiotherapy for nasopharyngeal carcinoma: extent and nature of the problem
Authors: Pow EHN , McMillan AS , Leung WK , Kwong DLW , Wong MCM 
Published: June 2003

Objective: To measure the oral health status of southern Chinese nasopharyngeal carcinoma (NPC) survivors 1–4 years after radiotherapy.Subjects and Methods: A total of 109 subjects participated in this cross‐sectional study. Thirty‐eight subjects were NPC survivors, 40 subjects were patients newly diagnosed with NPC and 31 were healthy subjects. Verified clinical examination techniques were used to assess limitation of jaw opening, the presence of mucositis, candidiasis, dental caries, periodontal disease [community periodontal index (CPI)] including attachment loss (ALoss) and prosthetic status/need. Differences among three groups were tested by chi‐squared and Kruskal–Wallis tests. Relationships between selected clinical variables and radiation parameters were analysed using Spearman's rank correlation coefficients.Results: The NPC survivors attended for dental treatment more frequently than the other groups (P < 0.01). NPC survivors had significant xerostomia (92%, P < 0.01), trismus (29%, P < 0.01), a higher prevalence of clinical candidiasis (24%, P < 0.01), a greater DMFT (16.4 ± 7.0, P < 0.01), more decay/filled roots (2.1 ± 2.9, P = 0.01) compared with new NPC patients and controls. No difference was found in CPI, ALoss, prosthetic status and need between groups. Dry mouth and tooth hypersensitivity were the most common oral problems perceived by the NPC survivors.Conclusion: Despite having regular dental follow‐ups, oral health was compromised in NPC survivors 1–4 years postradiotherapy.
The prevalence of tongue lesions in 5150 Turkish dental outpatients
Authors: Avcu N , Kanli A 
Published: June 2003

Objective: The aim of this study was to assess the prevalence of nine tongue conditions and relate to data obtained about oral hygiene or habits in Turkish dental outpatients.Subjects: A total of 5150 subjects (2837 women, 2313 men) were included in this study.Results: Of the 5150 subjects, 2690 subjects were detected as having tongue lesions with a prevalence of 44.2 and 62.0% for women and men, respectively. The difference was found to be statistically significant (P < 0.0001). There was a strong correlation between tongue lesions and increasing age. There was also a strong association between tongue lesions and smoking, black tea drinking, and fair or poor oral hygiene. Hairy and coated tongue was significantly higher in males. Contrary to this, papillary atrophy was more prominent in women.Conclusion: A strong correlation was found between tongue lesions and age, sex, oral hygiene and habits in Turkish dental outpatients. An efficient oral health program such as the elimination of risk habits and attention to cultural practices may improve tongue hygiene.