bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myotonic dystrophy—no evidence for preferential transmission of the mutated allele: A prenatal analysis
Authors: Zunz Eran , Abeliovich Dvorah , Halpern Gabrielle J. , Magal Nurit , Shohat Mordechai 
Published: April 2004

AbstractMyotonic dystrophy is the commonest autosomal dominant type of muscular dystrophy in adults. It is one of the trinucleotide repeat expansion disorders, and its severity correlates with the number of CTG repeats in the myotonic dystrophy gene. It has been suggested that myotonic dystrophy exhibits the phenomenon of preferential transmission of the larger mutated alleles that has been described in other trinucleotide repeat disorders. Several authors have reported that the frequency of transmission of the mutated alleles is higher than 50%—a finding that, if true, does not comply with the Mendelian laws of segregation. However, these studies were based on data from the analysis of pedigrees with ascertainment bias. In our study, we determined the frequency of transmission of mutated alleles using data from prenatal molecular studies, which are not subject to ascertainment bias. This is the first study to examine the segregation of the mutated alleles in myotonic dystrophy in pregnancy. Eighty‐three fetuses were examined, 30 of 62 mothers (48.38%) and 8 of 21 fathers (38.09%) transmitted the mutated allele, giving an overall transmission rate of 45.78%. We found no evidence of statistically significant deviation of the frequency of transmission of the mutated alleles from the 50% expected in autosomal dominant disorders. This study, unlike previous ones, excludes preferential transmission in myotonic dystrophy, a finding that may be attributable to the lack of correction for ascertainment bias in previous studies and to the use of prenatal data in this study. © 2004 Wiley‐Liss, Inc.
Minimal clinical expression of the holoprosencephaly spectrum and of Currarino syndrome due to different cytogenetic rearrangements deleting the sonic hedgehog gene and the HLXB9 gene at 7q36.3
Authors: Horn Denise , Tönnies Holger , Neitzel Heidemarie , Wahl Dagmar , Hinkel Georg Klaus , Moers Arpad von , Bartsch Oliver 
Published: April 2004

AbstractWe report clinical, cytogenetic, and molecular cytogenetic studies on four patients with subtle or submicroscopic 7q36 deletions either of de novo origin or resulting from a cryptic parental translocation. Fluorescence in situ hybridization (FISH) studies indicated that in all four patients, the Sonic Hedgehog gene (SHH) and the homeobox gene HLXB9, among others, are comprised in the deletions. Besides mental retardation and short stature, all patients showed only minimal manifestations of the holoprosencephaly (HPE) spectrum and only one displayed symptoms of the Currarino syndrome. Patient 1 had a de novo 7q36.1‐qter deletion and showed microcephaly, ptosis, sacral agenesis, tethered cord, but no structural brain anomaly. Patient 2 had a submicroscopic de novo 7q36 deletion detected by FISH, and showed facial and cerebral microsigns of the HPE spectrum. Patient 3 had a 7q36 deletion found by subtelomere FISH testing that was the unbalanced product of a subtle maternal 7q;10q translocation. She presented facial and ocular microsigns, but no structural abnormality of the brain. Patient 4 showed no specific syndromal pattern and was found to have a cryptic unbalanced de novo translocation of the terminal parts of chromosomes 7q and 9p by subtelomere FISH. Patients 2, 3, and 4 represent the first report of a de novo submicroscopic 7q36 deletion, the second report of a familial subtle translocation of 7q36, and the first report of an unbalanced de novo submicroscopic translocation of 7q36, respectively. Our results stress the importance of 7q36 deletion studies by FISH in patients with microsigns of the HPE spectrum. © 2004 Wiley‐Liss, Inc.
Treacher Collins syndrome with craniosynostosis, choanal atresia, and esophageal regurgitation caused by a novel nonsense mutation in TCOF1
Authors: Horiuchi Katsumi , Ariga Tadashi , Fujioka Hirotaka , Kawashima Kunihiro , Yamamoto Yuhei , Igawa Hiroharu , Sakiyama Yukio , Sugihara Tsuneki 
Published: April 2004

AbstractTreacher Collins syndrome (TCS) is caused by mutations in TCOF1 of the nonsense, small deletion, and small insertion types, which most likely result in haploinsufficiency. We report a novel de novo nonsense mutation 2731C → T, resulting in Arg911Stop, which truncates the protein. Our patient had the classic findings of TCS, but with documented craniosynostosis, choanal atresia, and esophageal regurgitation. © 2004 Wiley‐Liss, Inc.
A retrospective survey of perinatal risk factors of 104 living children with holoprosencephaly
Authors: Stashinko Elaine E. , Clegg Nancy J. , Kammann Heather A. , Sweet Vicki T. , Delgado Mauricio R. , Hahn Jin S. , Levey Eric B. 
Published: April 2004

AbstractHoloprosencephaly (HPE) is a brain malformation resulting from a primary defect in development of the basal forebrain during early gestation. Prenatal genetic and environmental factors and birth outcomes were described in a population of 104 children with holoprosencephaly referred to three clinical centers from 1998 through 2002. The mean child age was 4 years. Of cases karyotyped, 9% presented with a chromosomal abnormality. This study of living children with holoprosencephaly, the majority of whom are cytogenetically normal, provides new information on the subsample of children with a less severe phenotype. Most children were born at term; about 51% were microcephalic at birth. Consistent with previous research, the association between HPE and maternal history of diabetes merits further investigation. Several findings have important implications for future research. Only 22% of the children in this study sample were diagnosed with holoprosencephaly prenatally. The vast majority of children (72%) were diagnosed with HPE between birth and 1 year of age. Also, 19% of the cases referred to the Carter Centers with HPE were not confirmed on scan review. When possible, future population‐based epidemiological studies should emphasize mechanisms that identify children with HPE outside of the newborn period and confirm the diagnosis by review of MRI or high quality CT brain scan. © 2004 Wiley‐Liss, Inc.
Serotonin transporter regulatory region polymorphism is associated with anorexia nervosa
Authors: Matsushita Sachio , Suzuki Kenji , Murayama Masanobu , Nishiguchi Naoki , Hishimoto Akitoyo , Takeda Aya , Shirakawa Osamu , Higuchi Susumu 
Published: April 2004

AbstractSeveral lines of evidence support possible serotonin transporter (5‐HTT) involvement in modulating eating disorders (ED). The 5‐HTT gene is a good candidate for genetic studies on the course of ED, despite controversy concerning the association between polymorphism in the 5‐HTT gene promoter region (5‐HTTLPR) and ED. Comparison of 5‐HTTLPR distribution in 195 female Japanese ED patients and 290 age‐ and gender‐matched control subjects facilitated examining the association between the course of the disease and 5‐HTTLPR in 138 of 195 ED subjects. The 5‐HTTLPR S allele frequency was significantly higher in subjects with anorexia nervosa (AN) than in control subjects. Among subjects observed ≥3 years, the S allele frequency was significantly higher in those diagnosed as AN at ED onset than in those diagnosed as AN in this study. The 5‐HTTLPR S allele might play some role in the development of AN with persistent disease. © 2004 Wiley‐Liss, Inc.
Fracture toughness of mountain gorilla (Gorilla gorilla beringei) food plants
Authors: Elgart‐Berry Alison 
Published: April 2004

AbstractMountain gorillas, the largest extant primates, subsist almost entirely on plant matter. Moreover, their diet includes a substantial amount of structural material, such as bark and stems, which other primates tend to avoid. Accordingly, the robust masticatory apparatus of gorillas may be adaptive to this presumably tough diet; however, quantitative information on this subject is lacking. In this study the fracture toughness of mountain gorilla foods was examined for the first time. Samples of 44 food plants from Bwindi‐Impenetrable National Park (BINP) and Mgahinga Gorilla National Park (MGNP) were tested. These parks are inhabited by two gorilla populations that regarded by some as being distinct at the subspecific taxonomic level. Although food toughness did not differ between the two populations, both diets contained tough items. Tree barks were the toughest food items (varying from 0.23 to 8.2 kJ/m2), followed by shrub barks, pith, and stems. The toughness of leaves and fruit was negligible compared to that of bark. The toughness of bamboo was low in comparison to the toughest food items. Accordingly, the prominent toughness of bark, pith, and stems may be key factors in the evolution of orofacial robusticity in mountain gorillas. Am. J. Primatol. 62:275–285, 2004. © 2004 Wiley‐Liss, Inc.
Effect of glycerol and dimethyl sulfoxide on cryopreservation of rhesus monkey (Macaca mulatta) sperm
Authors: Si Wei , Zheng Ping , Li Yahui , Dinnyes Andras , Ji Weizhi 
Published: April 2004

AbstractGlycerol and dimethyl sulfoxide (DMSO) are widely used as penetrating cryoprotectants in the freezing of sperm, and various concentrations are applied in different species and laboratories. The present study aimed to examine the effect of these two cryoprotectants at different concentrations (2%, 5%, 10%, and 15% glycerol or DMSO) on rhesus monkey sperm cryopreservation. The results showed that the highest recovery of post‐thaw sperm motility, and plasma membrane and acrosome integrity was achieved when the sperm was frozen with 5% glycerol. Spermatozoa cryopreserved with 15% DMSO showed the lowest post‐thaw sperm motility, and spermatozoa cryopreserved with 15% glycerol and 15% DMSO showed the lowest plasma membrane integrity among the eight groups. The results achieved with 5% glycerol were significantly better for all parameters than those obtained with 5% DMSO. The functional cryosurvival of sperm frozen with 5% glycerol was further assessed by in vitro fertilization (IVF). Overall, 85.7% of the oocytes were successfully fertilized, and 51.4% and 5.7% of the resulting zygotes developed into morulae and blastocysts, respectively. The results indicate that the type and concentration of the penetrating cryoprotectant used can greatly affect the survival of rhesus monkey sperm after it is frozen and thawed. The suitable glycerol level for rhesus monkey sperm freezing is 5%, and DMSO is not suitable for rhesus monkey sperm cryopreservation. Am. J. Primatol. 62:301;–306, 2004. © 2004 Wiley‐Liss, Inc.
Characterization of rice hull ash
Authors: Chaudhary D. S. , Jollands M. C. 
Published: April 2004

AbstractRice hulls, a byproduct of the rice industry, contain 60–90% silica and are unique within nature. The annual worldwide output of rice‐hull‐derived silica is more than 3.2 million tons, which poses environmental concerns because of disposal issues. Burning rice hulls, as a preparative step for energy production, is a useful solution to the growing environmental concern, a desirable outcome would be the economic use of the resulting silica‐rich hull ash. The economical usefulness of this silica ash in the filler market has been undermined by its limited dispersion abilities and poor interaction capability with polymers. In this study, some of the reasons for the poor performance of silica ash as a reinforcing filler in various polymeric composites were linked to its inherent characteristics: factors such as its impurity, irregular topography, porosity, and chemical and thermodynamic nature arising from its surface polarity that negatively influence the filler–matrix interactions. The silica ash obtained from a novel combustion process had about 6% (w/w) impurity, of which around 3% was volatile. We also propose that the silanation efficiency of silica ash is lower compared to other commercial silicas because of its porosity, which could hide a fraction of the silane used. Also, processing changed the particle size distribution, and this could have affected the agglomerating tendencies and seriously marked the reinforcing capabilities of the silica ash. The estimation of the surface silanol groups of the rice hull ash by thermogravimetric studies indicated that the surface silanol density was about 16/nm2. On a comparative scale, this value is comparable to the silanol density on precipitated silica, but a thermodynamic study of silica ash surface revealed a high surface free energy that contributed to its high aggregation tendencies and poor distribution and dispersion abilities. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1–8, 2004
Structure development in melt spinning of poly(ethylene‐co‐octene) filaments with various comonomer contents
Authors: Shan Haifeng , White James L. 
Published: April 2004

AbstractAn experimental study of the spinnability and the variation in crystallinity and orientation of melt spinning of poly(ethylene‐co‐octene) with different contents of comonomers was carried out. The spinning behavior of these polymers was investigated under different draw‐down ratios and temperatures and correlated to spinline stress. The melt‐spun filaments were characterized by wide‐angle X‐ray diffraction birefringence, and differential scanning calorimetry. S‐1 is a high‐density polyethylene and S‐2, S‐3, and S‐4 have 16, 22, and 38 wt % octene. An orthorhombic unit cell was found in all four polymers, but a dominant hexagonal structure (perhaps mesophase) was found for the highest octene level (S‐4). The orientation factors for the a‐, b‐, and c‐axis of the orthorhombic crystal structure and a‐axis of the hexagonal phase were then calculated. The crystalline orientation behavior of the lower octene copolymers (S‐1, S‐2, and S‐3) are similar and can be represented as a “row‐nucleated“ structure. However, the orientation behavior of S‐4 was different. The uniaxial mechanical properties were also measured. The Young's modulus and tensile strength generally increased with birefringence for all polymers. With increasing content of octene, the Young's modulus showed a decrease from semicrystalline thermoplastic toward an elastomer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 9–22, 2004
Innovative polyamide‐based packaging of fresh meat
Authors: Laurino C. , Laurienzo P. , Malinconico M. , Scoponi M. , Sorrentino A. , Vacca P. , Volpe M. G. 
Published: April 2004

AbstractInnovative polymeric films based on blends of nylon 6 and ethylene‐co‐vinyl alcohol, previously tested by contact with the simulating fat‐containing foods, were further tested as packaging for fresh minced meat. As quality attributes for the shelf‐life evaluation, the microbiological parameters and some chemical–physical parameters were chosen. The changes that occurred during the evaluation period of 6 days were monitored by several means on both the polymer films and the fresh meat. The results suggest that the barrier properties of the polymeric films were shown to play a determinant role in the lipid oxidation, thus confirming the previous evaluation of the simulating foods. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 23–29, 2004
Effect of chemically modified waste rubber powder as a filler in natural rubber vulcanizates
Authors: Yehia A. A. , Mull M. A. , Ismail M. N. , Hefny Y. A. , Abdel‐Bary E. M. 
Published: April 2004

AbstractWaste rubber powder (RP) was subjected to chemical modification by using different concentrations of oxidizing agents such as nitric acid and 30% hydrogen peroxide solution. This treatment leads to introducing some functional groups onto the surface of RP. The chemically modified RP was incorporated in natural rubber mixes either alone or in combination with carbon black (HAF). The physicomechanical properties of NR vulcanizates obtained were studied and compared to NR vulcanizates filled with untreated RP. It was found that the chemically modified RP improves tensile strength and aging resistance of NR vulcanizates compared with untreated RP. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 30–36, 2004
Dynamic mechanical properties of agricultural residues‐filled polystyrene
Authors: Abdel‐Goad Mahmoud A.‐Halim 
Published: April 2004

AbstractAgricultural residues (cotton straw) were added as very small particles to polystyrene (PS) at different weight ratios by using a melt‐mixing technique. The dynamic mechanical tests were performed over a wide range of temperatures and frequencies by using an ARES rheometer (Rheometrics Scientific) operated in the dynamic mode. The dynamic mechanical properties in terms of the storage modulus (G′), loss modulus (G″), compliance moduli, loss tangent, and dynamic viscosity were studied and compared for PS and PS composite. The results showed that the dynamic mechanical moduli and viscosity were found to increase with the addition of cotton straw and rise further with its loading increasing. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 37–40, 2004
Effect of molecular weight on the rheological properties of atactic poly(vinyl alcohol)/dimethylsulfoxide/water solution
Authors: Lyoo Won Seok , Lee Sung Jun , Kim Joon Ho , Noh Seok Kyun , Ji Byung Chul , Kim Byoung Chul 
Published: April 2004

AbstractThis article describes the molecular weight effect of atactic poly(vinyl alcohol) (a‐PVA) on the rheological properties of 7.5, 10.0, and 12.5 g/dL solutions of a‐PVA with number‐average degrees of polymerization (Pn) of 4000 and 1700 in dimethylsulfoxide/water mixture. a‐PVA with a Pn of 1700 solutions exhibited almost Newtonian flow behavior, whereas high molecular weight a‐PVA, with a Pn of 4000 solutions, exhibited shear‐thinning behavior. On the plot of storage and loss moduli of a‐PVA with a Pn of 1700 solutions, the dynamic storage modulus of a‐PVA, with a Pn of 1700 solutions, was smaller than the dynamic loss modulus over the frequency range of 10−1 to 102 rad/s. However, the dynamic storage modulus of a‐PVA, with a Pn of 4000 solutions, was smaller than the dynamic loss modulus in the sol state and, in the postgel state, the dynamic storage modulus became larger than the dynamic loss modulus, indicating the evolution of viscoelastic solid properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 41–46, 2004
Activation energy, free energy, enthalpy, and entropy changes associated with viscometric changes of extremely to moderately dilute aqueous solutions of polyvinylpyrrolidone at 288.15–313.15 K
Authors: Singh Man , Kumar Sanjay 
Published: April 2004

AbstractViscometric behavior of polyvinylpyrrolidone (PVP) was investigated for extremely dilute (0.002–0.010 g dL−1), dilute (0.02–0.10 g dL−1), and moderately dilute (0.20–1.00 g dL−1) solutions at 288.15, 290.15, 293.15, 295.15, 298.15, 300.15, 303.15, 305.15, 308.15, 311.15, and 313.15 K. The experimental data were plotted according to Jones–Dole, Fuoss, and Fedors equations. Intrinsic viscosity ([η]) variation with temperature indicated the existence of different hydrodynamic states of PVP in solution at different temperatures. The PVP was found to show polyelectrolyte behavior in extremely dilute solutions, probably attributable to the presence of partially polarizable >CO groups in the chain. Activation energy (ΔE), differential enthalpy (∂ΔH), entropy (∂ΔS), and free energy (∂ΔG) changes of viscous flow were derived from flow velocity and taken into account for interpretation of the results to better understand the hydrodynamic and conformational behavior of PVP. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 47–55, 2004
Propylene polymerization using MgCl2/ethylbenzoate/TiCl4 catalyst: Determination of titanium oxidation states
Authors: Al‐Arifi A. S. N. 
Published: April 2004

AbstractThe chemical interaction of the catalyst MgCl2/ethylbenzoate/TiCl4 with the cocatalysts triethylaluminum and trisobutylaluminum was investigated to establish a relationship between the titanium oxidation states and the catalytic activity, polymer isotacticity, and polymer molecular weight in propylene polymerizations. This interaction was studied using different Al : Ti molar ratios by measuring the changes of the titanium oxidation states at different polymerization times. Both hydrogen and alkyl aluminum caused a reduction of Ti4+ species to lower oxidation states species Ti3+ and Ti2+. However, the Ti4+ species reduction appeared to be incomplete. It was found that the Ti4+ species undergoes a severe reduction as the Al : Ti molar ratio increases from 50 to 230 as overreduction takes place. This change of the Ti3+ species percentage with time was found to correlate with the rate–time profiles of propylene polymerization. From this observation, it would be fair to conclude that the trivalent titanium species is more likely to be the active titanium species for propylene polymerization than the aforementioned catalyst system. On the other hand, hydrogen addition was found to cause an increase in Ti3+ species. The increases in both hydrogen amount and/or Al : Ti molar ratio were found to cause a decrease in both molecular weight and polypropylene isotactic index. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 56–62, 2004
Short‐beam and three‐point‐bending tests for the study of shear and flexural properties in unidirectional‐fiber‐reinforced epoxy composites
Authors: Sideridis E. , Papadopoulos G. A. 
Published: April 2004

AbstractThe bending properties of composite materials are often characterized with simply supported beams under concentrated loads. The results from such tests are commonly based on homogeneous beam equations. For laminated materials, however, these formulas must be modified to account for the stacking sequence of the individual plies. The horizontal shear test with a short‐beam specimen in three‐point bending appears suitable as a general method of evaluation for the shear properties in fiber‐reinforced composites because of its simplicity. In the experimental part of this work, the shear strength of unidirectional‐glass‐fiber‐reinforced epoxy resin composites was determined in different fiber directions with the short‐beam three‐point‐bending test. Also, the elastic constants and flexural properties of the same materials were determined from bending experiments carried out on specimens in the 0, 15, 30, 45, 60, 75, and 90° fiber directions with high span–thickness ratios. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 63–74, 2004
Crosslinking of high‐density polyethylene in the presence of organic peroxides
Authors: Anbarasan Ramasatamy , Babot Odile , Maillard Bernard 
Published: April 2004

AbstractThe crosslinking efficiency of various commercially available organic peroxides (dicumyl peroxide, O,O‐t‐butyl O‐2‐ethylhexylperoxycarbonate, t‐butyl peroxybenzoate, t‐butyl 3,5,5‐trimethylperoxyhexanoate, and t‐butyl 2‐ethylperoxyhexanoate) was tested on high‐density polyethylene (HDPE) in its molten state. The variations of the concentrations of the peroxides versus the crosslinking extent were plotted for these peroxides, and the values were compared. Dicumyl peroxide was found to be the best crosslinking agent for HDPE. The efficiency of the HDPE crosslinking with each peroxy derivative was analyzed on the basis of the behavior of the radicals generated from it. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 75–81, 2004