bluuebunny/crossref_metadata_2025_split huggingface dataset:
How does polyspermy happen in mammalian oocytes?
Authors: Wang Wei‐Hua , Day Billy N. , Wu Guang‐Ming 
Published: June 2003

AbstractPolyspermy is one of the most commonly observed abnormal types of fertilization in mammalian oocytes. In vitro fertilization (IVF) provides approaches to study the mechanisms by which oocytes block polyspermic fertilization. Accumulated data indicate that oocyte, sperm and insemination conditions are all related to the occurrence of polyspermic fertilization. A high proportion of immature and aged oocytes showed polyspermy as compared with mature oocytes. Preincubation of oocytes and/or sperm with oviductal epithelial cells or collected oviductal fluid before IVF reduces polyspermic penetration. Recently, it was found that an abnormal zona pellucida is one of main causes of polyspermy in human eggs. A high proportion of polyspermy has resulted from the use of a high concentration of capacitated spermatozoa at the site of fertilization, irrespective of in the in vivo or in vitro environment. Oviductal secretions or oviductal epithelial cells themselves can regulate the number of spermatozoa reaching or binding to the zona pellucida thus reducing multiple sperm penetration. Suboptimal in vitro conditions, such as supplementations in IVF media, pH, and temperature during IVF, also induce polyspermic fertilization in some mammals. Species‐specific differences are present regarding the relationship between insemination conditions and polyspermy. Microsc. Res. Tech. 61:335–341, 2003. © 2003 Wiley‐Liss, Inc.
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

AbstractPerinuclear 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

AbstractIn 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

AbstractBCL6 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

AbstractPatients 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

AbstractTo 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

AbstractHallervorden–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

AbstractA 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

AbstractThe 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

AbstractThe 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

AbstractFour 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

AbstractThe 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

AbstractThe 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

AbstractThe 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

AbstractCarbon 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.