bluuebunny/crossref_metadata_2025 huggingface dataset:
Modification of polyurethaneurea with PEG and YIGSR peptide to enhance endothelialization without platelet adhesion
Authors: Jun Ho‐Wook , West Jennifer L.
Published: August 2004

Improved endothelialization without platelet adhesion is essential to enhance the long‐term patency of synthetic vascular grafts and other blood‐contacting devices. We have developed a dually modified polyurethaneurea by incorporating endothelial cell adhesive YIGSR peptide sequences as chain extenders and nonthrombogenic PEG as a soft segment (PUUYIGSR‐PEG) in the polymer backbone. PUUYIGSR‐PEG was successfully synthesized and characterized by proton NMR, FTIR, GPC, DSC, ESCA, and contact angle measurement. Despite having similar molecular weight, the peptide/PEG‐modified polyurethaneurea (PUUYIGSR‐PEG) showed superior mechanical properties compared to the control PEG‐modified polyurethaneurea (PUUPPD‐PEG). Virtually no platelet adhesion was observed on PUUYIGSR‐PEG, while endothelial cell adhesion, spreading, and migration were significantly greater on PUUYIGSR‐PEG compared to PUUPPD‐PEG. Thus, this bioactive polymer may be an appropriate biomaterial for small diameter vascular grafts. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 131–139, 2005
Preprocessing of rotamers for protein design calculations
Authors: Shah Premal S. , Hom Geoffrey K. , Mayo Stephen L.
Published: August 2004

We have developed a process that significantly reduces the number of rotamers in computational protein design calculations. This process, which we call Vegas, results in dramatic computational performance increases when used with algorithms based on the dead‐end elimination (DEE) theorem. Vegas estimates the energy of each rotamer at each position by fixing each rotamer in turn and utilizing various search algorithms to optimize the remaining positions. Algorithms used for this context specific optimization can include Monte Carlo, self‐consistent mean field, and the evaluation of an expression that generates a lower bound energy for the fixed rotamer. Rotamers with energies above a user‐defined cutoff value are eliminated. We found that using Vegas to preprocess rotamers significantly reduced the calculation time of subsequent DEE‐based algorithms while retaining the global minimum energy conformation. For a full boundary design of a 51 amino acid fragment of engrailed homeodomain, the total calculation time was reduced by 12‐fold. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1797–1800, 2004
Lipid micelles stimulate the secretion of triglyceride‐enriched apolipoprotein B48‐containing lipoproteins by Caco‐2 cells
Authors: Chateau Danielle , Pauquai Thomas , Delers François , Rousset Monique , Chambaz Jean , Demignot Sylvie
Published: August 2004

Intestinal triglyceride‐rich lipoproteins (TRL) are synthesized from dietary lipids. This study was designed to evaluate the effects of lipid micelles, mimicking post‐digestive duodenal micelles, on the fate of apolipoprotein B (apoB)48‐containing lipoproteins by Caco‐2 cells. Such micelles, consisting of oleic acid (OA), taurocholate, 2‐monooleoylglycerol (2‐MO), cholesterol (Chol), and L‐α‐lysophospatidylcholine, were the most efficient inducers of OA uptake and esterification. The efficiency of TG and apoB48 secretion increased specifically as a function of cell differentiation. PAGE analysis of secreted lipoproteins separated by sequential ultracentrifugation after [35S] labeling revealed differences in the secretion of apoB100‐ and apoB48‐containing lipoproteins. In absence of micelles, apoB48 was secreted mostly in “HDL‐like” particles, as observed in enterocytes in vivo. Micelle application increased 2.7‐fold the secretion of apoB, resulting in 53 times more apoB48 being recovered as TG‐enriched lipoproteins at d < 1.006 g/ml. Electron microscopy revealed the presence of lipid droplets in the secretory pathway and the accumulation of newly synthesized TG in cytoplasmic lipid droplets, as in enterocytes in vivo. We showed that these droplets could be used for secretion. However, apoB48 preferentially bound to newly synthesized TG in the presence of micelles, accounting in part for the functional advantage of apoB editing in the intestine. While Caco‐2 cells express both apoB isoforms, our results show that the apical supply of complex lipid micelles favors the physiological route of apoB48‐containing TG‐enriched lipoproteins. © 2004 Wiley‐Liss, Inc.
Prospect of temperature determination using degenerate four‐wave mixing with sub‐20 fs pulses
Authors: Hornung Thomas , Skenderović Hrvoje , Kompa Karl‐Ludwig , Motzkus Marcus
Published: August 2004

Femtosecond time‐resolved degenerate four‐wave mixing (DFWM) spectroscopy with ultrashort laser pulses was applied to probe pure rotational Raman transitions of the H2 molecule. Owing to the broad bandwidth of the sub‐20 fs pulse, several pure rotational Stokes and anti‐Stokes transitions are simultaneously excited with the same pulse, making the experiment relevant for thermometry in combustion processes. Simulations of the DFWM signal accurately predict how the change in population distribution due to changes in temperature influences the shape of the transients and the corresponding Fourier transform. The influence of the pulse duration was also investigated. The relative peak intensities in fast Fourier transform spectra were employed for temperature determination. First measurements at room temperature show good agreement with theory. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of ergosterol in paddy rice using solid phase extraction
Authors: Srzednicki George , Craske John , Nimmuntavin Chintana , Mantais Linda George , Wattananon Saranya
Published: August 2004

Ergosterol, the predominant sterol found in most fungi, is considered as an indicator of fungal invasion in grain. An extraction method based on solid phase extraction (SPE) has been developed for determination of ergosterol in unmilled rice, generally called paddy. The samples obtained by extraction through SPE have been analysed by HPLC. The method has been validated in experiments with paddy subjected to different drying treatments and recoveries above 85% have been obtained. SPE appeared to be simple, quick, reliable and consistent for ergosterol analysis. The ergosterol levels obtained in the paddy samples were found to be within the expected range and were comparable with those found using conventional methods. Copyright © 2004 Society of Chemical Industry
Laser radiation tooth bleaching
Authors: Jelínková H , Dostálová T , Němec M , Šulc J , Koranda P , Houšová D , Miyagi M , Shi Y W , Matsuura Y
Published: August 2004

The study describes the preclinical experience with laser-activated bleaching agent for discolored teeth. Extracted human upper central incisors were selected and in a bleaching experiment 35% hydrogen peroxide was used. Three different laser systems and halogen-light unit for activation of the bleaching agent were used: alexandrite laser (wavelength 750 nm and SHG – 375 nm), Nd:YAG laser (wavelength 1.064 μm), and Er:YAG laser (wavelength 2.94 μm). The halogen light unit was used in a standard regime. The enamel surface was analyzed in the scanning electron microscope. The method of chemical oxidation results in a 2-3 shade change in one treatment. The halogen-light unit received the same effect with shorter time of bleaching process (from 630 s to 300 s). Alexandrite laser (750 nm) and bleaching agent helped to reach the desired color shade after shorter time (400 s). Alexandrite laser (375 nm) and Nd:YAG laser had no effect on the longevity of the process of bleaching. Overheating of chemical bleaching agent was visible after Er:YAG laser activation (195 s). This effect was only local, no crack or essential surface modifications were observed.
Thermosensitive Micelles Self‐Assembled by Novel N‐Isopropylacrylamide Oligomer Grafted Polyphosphazene
Authors: Zhang Jian Xiang , Qiu Li Yan , Zhu Kang Jie , Jin Yi
Published: August 2004

Summary: A novel thermosensitive amphiphilic copolymer of PNIPAm grafted polyphosphazene (PNIPAm‐g‐PPP) has been synthesized through a co‐substitution reaction of poly(dichlorophosphazene) with amino terminated NIPAm oligomer and glycine ethyl ester (GlyEt). The polymer obtained had a molar ratio of 1:5.25 PNIPAm to GlyEt and had a lower critical solution temperature (LCST) near 30 °C. The formation of polymeric micelles was confirmed by fluorescence, dynamic light scattering and transmission electron microscopy measurements.

The structure and formation of thermosensitive micelles of poly(N‐isopropylacrylamide) grafted polyphosphazenes synthesized here.

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The structure and formation of thermosensitive micelles of poly(N‐isopropylacrylamide) grafted polyphosphazenes synthesized here.
High‐Density Polyethylene Micro‐ and Nanocomposites: Effect of Particle Shape, Size and Surface Treatment on Polymer Crystallinity and Gas Permeability
Authors: Osman Maged A. , Atallah Ayman
Published: August 2004

Summary: High‐density polyethylene (HDPE) micro‐ and nanocomposites with spherical and platelike inclusions were prepared and the effect of filler particles on polymer crystallinity and gas permeability was investigated. Platelike inclusions strongly reduce the polymer permeability coefficient, while spherical ones have no influence on it, irrespective of their size. The reduction in gas permeability depends on the average aspect ratio of the inclusions, which in turn depends on the exfoliation of the organo‐montmorillonites (OM) and consequently on its surface treatment.

A TEM micrograph of 3 vol.‐% 2C18 · M‐HDPE nanocomposite, showing partial exfoliation of the organo‐montmorillonite.

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A TEM micrograph of 3 vol.‐% 2C18 · M‐HDPE nanocomposite, showing partial exfoliation of the organo‐montmorillonite.
Blastocysts produced by nuclear transfer between chicken blastodermal cells and rabbit oocytes
Authors: Liu Shu‐Zhen , Zhou Zhen‐Ming , Chen Tao , Zhang Yan‐Ling , Wen Duan‐Cheng , Kou Zhao‐Hui , Li Zan‐Dong , Sun Qing‐Yuan , Chen Da‐Yuan
Published: August 2004

Interspecies nuclear transfer (INT) has been used as an invaluable tool for studying nucleus–cytoplasm interactions; and it may also be a method for rescuing endangered species whose oocytes are difficult to obtain. In the present study, we investigated interaction of the chicken genome with the rabbit oocyte cytoplasm. When chicken blastodermal cells were transferred into the perivitelline space of rabbit oocytes, 79.3% of the couplets were fused and 9.7% of the fused embryos developed to the blastocyst stage. Both M199 and SOF medium were used for culturing chicken–rabbit cloned embryos; embryo development was arrested at the 8‐cell stage obtained in SOF medium, while the rates of morulae and blastocysts were 12.1 and 9.7%, respectively, in M199 medium. Polymerase chain reaction (PCR) amplification of nuclear DNA and karyotype analyses confirmed that genetic material of morulae and blastocysts was derived from the chicken donor cells. Analysis mitochondrial constitution of the chicken–rabbit cloned embryos found that mitochondria, from both donor cells and enucleated oocytes, co‐existed. Our results suggest that: (1) chicken genome can coordinate with rabbit oocyte cytoplasm in early embryo development; (2) there may be an 8‐ to 16‐cell stage block for the chicken–rabbit cloned embryos when cultured in vitro; (3) mitochondrial DNA from the chicken donor cells was not eliminated until the blastocyst stage in the chicken–rabbit cloned embryos; (4) factors existing in ooplasm for somatic nucleus reprogramming may be highly conservative. Mol. Reprod. Dev. 69: 296–302, 2004. © 2004 Wiley‐Liss, Inc.
Tension‐free vaginal tape (TVT) for the treatment of occult stress urinary incontinence in women undergoing prolapse repair: A prospective study of 100 consecutive cases
Authors: Groutz Asnat , Gold Ronen , Pauzner David , Lessing Joseph B. , Gordon David
Published: August 2004

Aims

Clinically continent women with genitourinary prolapse and occult stress urinary incontinence (SUI) are considered to be at high risk of developing symptomatic SUI once the prolapse is repaired. We studied the efficacy and safety of tension‐free vaginal tape (TVT) procedure in preventing postoperative SUI in these women.

Methods

One hundred consecutive women (mean age 66.7 ± 9.9 years) with significant genitourinary prolapse and occult SUI were prospectively enrolled. Preoperatively, none of the women complained of SUI. However, all had urodynamically‐confirmed occult SUI, revealed by repositioning of the prolapse. Surgical intervention was comprised of transvaginal prolapse repair and prophylactic TVT procedure. Main outcome end points included operative morbidity, postoperative SUI, persistent or de novo urge incontinence, and voiding dysfunction.

Results

The mean follow‐up period was 27 months (range: 12–52 months). There was only one case of technique‐related bladder perforation with no adverse outcome. Two other patients had postoperative urinary retention necessitating catheterization for more than 7 days, none of whom required any surgical intervention. Vaginal erosion of the tape was diagnosed in three patients, all of whom were successfully treated by excision of the eroded tape. Two (2%) patients developed urodynamically‐confirmed SUI within 1 year postoperatively. However, postoperative urodynamics revealed asymptomatic sphincteric incontinence in 15 (15%) other patients. Thirteen (72%) of 18 patients with preoperative urge incontinence had postoperative persistent urge incontinence. De novo urge incontinence developed postoperatively in 8 (8%) patients.

Conclusions

TVT procedure is effective and safe in patients with occult SUI undergoing prolapse repair. Long‐term durability of this procedure is yet to be established. © 2004 Wiley‐Liss, Inc.
Quantifying optimal mesh and ring design costs
Authors: Stidsen Thomas , Glenstrup Arne John
Published: August 2004

During the last decade telecommunication operators have been deploying WDM (Wavelength Division Multiplexing) technology to satisfy the exponential growth in global communication. While facilitating the advanced information society of today, this has also led to a higher dependency on the networks, and furthermore the high capacity utilization of optical fibers means that a single link failure will influence many users and enterprises. For these reasons, protection of network connections has become a major competitive parameter for the operators. Currently, the most popular protection method is ring protection, due to its simplicity, requiring only basic management functionality and operating with local restoration control. While many optical rings have been deployed, little work has been published on exactly what the cost of ring networks are, compared to general mesh networks. In this article we perform a quantitative comparison between ring protection and mesh protection, using real world network data and realistic prices for network components. Extending classic LP flow models to take rings and node costs into account, and using a link‐path based mesh network LP model, we are able to perform a total cost comparison of the two architectures, and of manual ring network design. The results suggest that the price of mesh network components must be reduced significantly to be competitive with ring based networks, and also that manual network design does not necessarily lead to the most cost‐efficient designs. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2005
A distributed memory parallel implementation of the multigrid method for solving three‐dimensional implicit solid mechanics problems
Authors: Namazifard A. , Parsons I. D.
Published: August 2004

We describe the parallel implementation of a multigrid method for unstructured finite element discretizations of solid mechanics problems. We focus on a distributed memory programming model and use the MPI library to perform the required interprocessor communications. We present an algebraic framework for our parallel computations, and describe an object‐based programming methodology using Fortran90. The performance of the implementation is measured by solving both fixed‐ and scaled‐size problems on three different parallel computers (an SGI Origin2000, an IBM SP2 and a Cray T3E). The code performs well in terms of speedup, parallel efficiency and scalability. However, the floating point performance is considerably below the peak values attributed to these machines. Lazy processors are documented on the Origin that produce reduced performance statistics. The solution of two problems on an SGI Origin2000, an IBM PowerPC SMP and a Linux cluster demonstrate that the algorithm performs well when applied to the unstructured meshes required for practical engineering analysis. Copyright © 2004 John Wiley & Sons, Ltd.
The perfectly matched layer for the ultra weak variational formulation of the 3D Helmholtz equation
Authors: Huttunen Tomi , Kaipio Jari P. , Monk Peter
Published: August 2004

We investigate the feasibility of using the perfectly matched layer (PML) as an absorbing boundary condition for the ultra weak variational formulation (UWVF) of the 3D Helmholtz equation. The PML is derived using complex stretching of the spatial variables. This leads to a modified Helmholtz equation for which the UWVF can be derived. In the standard discrete UWVF, the approximating subspace is constructed from local solutions of the Helmholtz equation. In previous studies plane wave basis functions have been advocated because they simplify the building of the UWVF matrices. For the PML domain we propose a special set of plane wave basis functions which allow fast computations and efficiently reduce spurious numerical reflections.

The method is validated by numerical experiments. In comparison to a low‐order absorbing boundary condition, the PML shows superior performance. Copyright © 2004 John Wiley & Sons, Ltd.
Immigrants, welfare reform, and the economy
Authors: Haider Steven J. , Schoeni Robert F. , Bao Yuhua , Danielson Caroline
Published: August 2004

The welfare reform bill adopted in the United States in 1996 limited the eligibility of immigrants for several government assistance programs, and early projections estimated that nearly half of the savings associated with the reforms would come from these immigrant restrictions. Several studies have found that subsequent program participation declined more for immigrants relative to natives, seemingly verifying the early projections. However, many of these restrictions were either rescinded by the federal government or superceded by state and local policies. In this paper, we first reproduce earlier findings that show the relative declines in program use among immigrants. We then show that much, but not all, of the relative decline in program use among immigrants can be explained by changing macroeconomic conditions. © 2004 by the Association for Public Policy Analysis and Management.
Waiting times for cancer care in Canadian children: Impact of distance, clinical, and demographic factors
Authors: Klein‐Geltink Julia E. , Pogany Lisa M. , Barr Ronald D. , Greenberg Mark L. , Mery Leslie S.
Published: August 2004

Background

The objective of this study was to evaluate the impact of distance from residence to pediatric oncology centers on waiting times to diagnostic assessment and treatment in Canadian children with cancer.

Procedure

Two thousand three hundred sixteen children (<15 years of age) captured by the Canadian Childhood Cancer Surveillance and Control Program's (CCCSCP) Treatment and Outcome Surveillance (TOS) system were included in the analysis. The number of days between onset of symptoms and first anti‐cancer therapy was compared for those living less than 25, 25–99, and more than 100 kilometers from their treating center. For each time period, the adjusted odds of falling into the longest time quartiles were estimated using logistic regression analysis.

Results

Thirty‐four percent (n = 786) of children lived more than 100 kilometers from their treating center. There were no significant differences in age at diagnosis (P = 0.33), sex (P = 0.68), or ICCC diagnosis (P = 0.02) by distance from center, though there was a significant difference in region of residence (P < 0.01) and the first health care professional contacted (P < 0.01). Except for waiting time from first health care contact to first assessment by treating oncologist which increased with increasing distance (P < 0.01), there were no significant differences in waiting times by distance. When adjusted for important demographic and clinical characteristics, distance to center did not affect the odds of waiting longer for any event.

Conclusions

Distance to treating center had no significant impact on waiting times for important diagnostic and treatment events, when adjusted for age at diagnosis, diagnosis, region, and first health care professional seen. © 2004 Wiley‐Liss, Inc.
Evaluation of selective toxicity of five pesticides against Plutella xylostella (Lep: Plutellidae) and their side‐effects against Cotesia plutellae (Hym: Braconidae) and Oomyzus sokolowskii (Hym: Eulophidae)
Authors: Shi Zu‐hua , Guo Shi‐jian , Lin Wen‐cai , Liu Shu‐sheng
Published: August 2004

The toxicities of five pesticides commonly used in vegetable fields to the larvae of the diamondback moth, Plutella xylostella (L) and its two major parasitoids, Cotesia plutellae (Kurdjumov) and Oomyzus sokolowskii (Kurdjumov), were evaluated in the laboratory using several bioassays. When tested at the rates recommended for field application by the manufacturer, fipronil, avermectin and chlorfluazuron produced over 95% mortality on third‐instar larvae of P xylostella, but fenvalerate and methomyl did not produce any substantial mortality to such larvae, and over 70% of P xylostella larvae could still pupate normally after feeding on cabbage leaf treated with the two pesticides. In a residual contact assay with adult parasitoids, fipronil and methomyl caused over 93% mortality within 24 h; fenvalerate killed approximately 55% of the adults within 24 h; avermectin and chlorfluazuron showed differential toxicity to the two parasitoids. Avermectin was extremely harmful to O sokolowskii but slightly toxic to C plutellae, while chlorfluazuron was more toxic to C plutellae than to O sokolowskii. In the residue assay with cocoons of C plutellae and pupae of O sokolowskii developed within P xylostella pupae, treatments with pesticides did not reduce adult emergence. However, the mortality of C plutellae adults emerged from the fipronil‐treated cocoons increased greatly within 24 h post‐emergence; adults from the fenvalerate‐treated cocoons parasitized less host larvae. Treatments with fenvalerate and methomyl significantly increased the mortality of O sokolowskii adults within 24 h post‐emergence. Recommendations of choosing pesticides for the control of P xylostella are given. Copyright © 2004 Society of Chemical Industry
Hydrogen bonding interaction in sarcosine–water complex using ab initio and DFT method
Authors: Chaudhari Ajay , Sahu Prabhat K. , Lee Shyi‐Long
Published: August 2004

The hydrogen bonding interaction in the Sarcosine (N‐methylglycine)–water complex is studied using ab initio, MP2, and density functional theory (DFT/B3LYP). For this complex, binding energies, dipole–dipole interactions, chemical hardness, and chemical potential have been calculated. Three different basis sets, viz. 6‐311+G, 6‐311++G, and 6‐311++G*, have been used to optimize the geometries by all three methods. The basis set superposition errors are also calculated, and the corrected binding energies are reported for this complex. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Impact of a school district's science reform effort on the achievement and attitudes of third‐ and fourth‐grade students
Authors: Shymansky James A. , Yore Larry D. , Anderson John O.
Published: August 2004

This article is about one school district's effort to reform its elementary science curriculum through a program of professional development called Science, Parents, Activities and Literature (Science PALs). The differential exposure of the district's K–6 teachers to Science PALs and differences in how well teachers implemented Science PALs‐type inquiry strategies allowed us to conduct a quasi‐experimental study of the impact of Science PALs on student achievement and attitudes. We measured achievement with an instrument based on items taken from the Third International Mathematics and Science Study (TIMSS; International Association for the Evaluation of Educational Achievement, 1997) and selected attitudes about science with the Student Perceptions of Classroom Climate (SPOCC; Yore et al., 1998), an instrument that we designed. Our analyses of student attitude scores as a function of years of teacher participation in Science PALs and supervisor's rating of a teacher's implementation of the project's instructional approaches showed a significant overall positive impact on student attitudes toward school science. Student TIMSS scores on multiple‐choice items or constructed‐response items did not improve significantly when analyzed by the number of years a student's teacher was involved in the Science PALs effort or by the supervisor's rating of that implementation. We found no significant differences in attitude or achievement scores among students taught by a series of teachers rated high, medium, or low in quality of implementation by the district's science supervisor. We discuss possible explanations for the lack of clear and positive connections between Science PALs and student performance in light of the increased focus on accountability in reform projects. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 771–790, 2004
The value of ultrasound in the prediction of successful induction of labor
Authors: Rane S. M. , Guirgis R. R. , Higgins B. , Nicolaides K. H.
Published: August 2004

Objectives

To examine the value of pre‐induction sonographic assessment of cervical length, posterior cervical angle and occipital position in the prediction of the induction‐to‐delivery interval within 24 h, the likelihood of vaginal delivery within 24 h, the likelihood of Cesarean section and to compare sonographic assessment with the Bishop score.

Methods

In 604 singleton pregnancies, induction of labor was carried out at 35–42 weeks of gestation. Immediately before induction, transvaginal sonography was performed for measurement of cervical length and posterior cervical angle and a transabdominal scan was carried out to determine the position of the fetal occiput. The value of occipital position, posterior cervical angle, cervical length, parity, gestational age, maternal age, and body mass index (BMI) on the induction‐to‐delivery interval within 24 h, the likelihood of vaginal delivery within 24 h and the likelihood of Cesarean section were investigated by Cox proportional hazard model or logistic regression analysis.

Results

Vaginal delivery occurred in 484 (80.1%) women and this was within 24 h of induction in 388 (64.2%). Cesarean section was performed in 120 (19.9%). Occiput‐anterior (OA) and transverse (OT) positions were analyzed as one group as the odds ratios (OR) and the HR were similar and different from occiput‐posterior (OP), which was analyzed as another group. Prediction of the induction‐to‐delivery interval was provided by the occipital position, pre‐induction cervical length, parity and posterior cervical angle. Prediction of the likelihood of vaginal delivery within 24 h was provided by the occipital position, cervical length, posterior cervical angle and BMI. Prediction of the likelihood of Cesarean section was provided by the occipital position, cervical length, parity, maternal age and BMI. In the prediction of vaginal delivery within 24 h, for a specificity of 75%, the sensitivity for ultrasound findings was 89% and for the Bishop score it was 65%. The respective sensitivities for Cesarean section were 78% and 53%.

Conclusion

In women undergoing induction of labor, significant independent prediction of the induction‐to‐delivery interval within 24 h, the likelihood of vaginal delivery within 24 h and the likelihood of Cesarean section are provided by pre‐induction cervical length, occipital position, posterior cervical angle and maternal characteristics. Sonographic parameters were superior to the Bishop score in the prediction of the outcome of induction. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Clinical significance of uterine artery blood flow velocity waveforms during provoked uterine contractions in high‐risk pregnancy
Authors: Li H. , Gudmundsson S. , Olofsson P.
Published: August 2004

Objective

To determine whether, in a group of high‐risk pregnancies undergoing an oxytocin challenge test (OCT), uterine artery Doppler velocimetry will identify fetuses at risk of distress during the provoked contractions.

Methods

Bilateral uterine artery Doppler velocimetry was performed simultaneously with electronic fetal heart rate (FHR) recordings in 67 high‐risk pregnancies subjected to an OCT. Flow velocity waveforms (FVWs) were classified according to pulsatility index (PI), presence of diastolic notching and a novel classification of FVW shapes. The OCT was classified as negative (normal) or positive (late FHR decelerations). Only OCT‐negative cases were allowed a trial of vaginal delivery. Non‐parametric statistical methods were used to test for differences between the OCT groups.

Results

There was no difference in prevalence of high PI or diastolic notching in OCT‐positive (n = 10) and OCT‐negative (n = 57) cases at basal (resting) measurements or between uterine contractions in either uterine artery (P ≥ 0.3). During contractions the PI could not be used for assessment due to the biphasic shape of the FVWs, but there was no difference in distribution of FVW classes between the groups in either the placental side (P ≥ 0.3) or contraplacental side (P ≥ 0.6) uterine artery. No significant associations between PI or FVW class distribution and birth asphyxia or operative delivery for fetal distress in labor were found (P ≥ 0.1).

Conclusions

During uterine contractions there is no difference in uterine artery FVW pattern between OCT‐positive and OCT‐negative cases. Recording of uterine artery FVWs during the OCT seems to be of limited clinical relevance. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
A possible association between the CCK-AR gene and persistent auditory hallucinations in schizophrenia
Authors: Sanjuan J. , Toirac I. , González J.C. , Leal C. , Moltó M.D. , Nájera C. , de Frutos R.
Published: August 2004

Recent studies have suggested that DNA variations in the CCK-AR gene might predispose individuals to schizophrenia and particularly to auditory hallucinations (AH). The aim of this study is to assess the association between AH, using a specific scale for AH in schizophrenia (PSYRATS), and the CCK-AR polymorphism at 779 in a Spanish sample. A total of 105 DSM-IV schizophrenic patients with AH and 93 unrelated controls were studied. Twenty-two patients were considered as persistent auditory hallucinators, which showed similar clinical and demographic characteristic than patients with episodic AH, but with the exception of the PSYRATS values. The persistent AH group showed an excess of the A1 allele when was compared with episodic or control groups. Our data support the possible role of the CCK-AR gene in the development of persistent AH in schizophrenic patients.
Genome based identification and analysis of the pre‐replicative complex of Arabidopsis thaliana
Authors: Masuda H.P. , Ramos G.B.A. , de Almeida-Engler J. , Cabral L.M. , Coqueiro V.M. , Macrini C.M.T. , Ferreira P.C.G. , Hemerly A.S.
Published: August 2004

Eukaryotic DNA replication requires an ordered and regulated machinery to control G1/S transition. The formation of the pre‐replicative complex (pre‐RC) is a key step involved in licensing DNA for replication. Here, we identify all putative components of the full pre‐RC in the genome of the model plant Arabidopsis thaliana. Different from the other eukaryotes, Arabidopsis houses in its genome two putative homologs of ORC1, CDC6 and CDT1. Two mRNA variants of AtORC4 subunit, with different temporal expression patterns, were also identified. Two‐hybrid binary interaction assays suggest a primary architectural organization of the Arabidopsis ORC, in which AtORC3 plays a central role in maintaining the complex associations. Expression profiles differ among pre‐RC components suggesting the existence of various forms of the complex, possibly playing different roles during development. In addition, the expression of the putative pre‐RC genes in non‐proliferating plant tissues suggests that they might have roles in processes other than DNA replication licensing.
RecQ helicase enhances homologous recombination in plants
Authors: Li Hong-Qing , Li Mei-Ru
Published: August 2004

RecQ helicase is a key component in the RecF pathway of Escherichia coli for initiation of homologous recombination. Here, we demonstrate that transient expression of RecQ gene in rice embryogenic cell increases the homologous recombination efficiency as much as 4‐fold. Further experiments reveal that this effect is influenced by the RecQ dosage. Stable expression of RecQ in rice dramatically increases the homologous recombination events 20‐ to 40‐fold in leaf tissue from different transgenic lines. This is the first evidence indicating that overexpression of RecQ gene can stimulate homologous recombination in plants.
Diel patterns in pelagic fish behaviour and distribution observed from a stationary, bottom-mounted, and upward-facing transducer
Authors: Axenrot Thomas , Didrikas Tomas , Danielsson Charlotte , Hansson Sture
Published: August 2004

Diel variation in pelagic fish distribution influences hydroacoustic abundance estimates. To study and quantify diel patterns in behaviour and spatial distribution in pelagic fish without causing avoidance reactions or attraction to any floating equipment or vessel we used a bottom-mounted, upward-facing transducer. Light intensities were measured as skylight and underwater light (at 5-m depth). The study was performed in a coastal area in the Baltic Sea, late July to mid-August in 2001 and 2002. The results provided additional information on fish behaviour and distribution valuable for future survey planning and in the analyses of hydroacoustic data from regular surveys in this area. At night, the data on hydroacoustic backscattering (sA) were less variable, the vertical distribution of fish was more even, with fewer fish in the deepest layer, and the percentage of single-echo detections was higher. The tilt angle of fish seemed to differ day and night, but trawling and target-strength distribution results taken together also implied a partial diel change in the fish assemblage in the midwater layers. The processes of formation and disintegration of schools happened rapidly and coincided with day and night transition periods.
Vaginal Birth After Cesarean Section: A Pilot Study of Outcomes in Women Receiving Midwifery Care
Authors: Avery Melissa D. , Carr Catherine A. , Burkhardt Patricia
Published: August 2004

A recent trend discouraging or not offering women a choice to labor after a cesarean birth has resulted in higher cesarean birth rates and lower rates of vaginal birth after cesarean birth (VBAC). The few studies describing midwifery practice have demonstrated favorable outcomes; however, the studies are too small to thoroughly evaluate critical outcomes. In this retrospective descriptive study, clinical outcome data were obtained from eight midwifery practices. The aims were to collect, aggregate, and analyze data from multiple midwifery practices and then describe outcomes. Usable data representing 649 trials of labor were submitted. Overall, 72% (range 64%‐100%) of women gave birth vaginally. Mean infant birth weight was 3,501 (SD = 534) g, and the mean Apgar scores were 7.99 (SD = 1.4; median 8) at 1 minute and 8.84 (SD = 0.8; median 9) at 5 minutes. Only 5.3% (n = 14) of infants were admitted to the neonatal intensive care unit. This small retrospective study demonstrates similar outcomes to those reported in the current literature. A larger prospective study to carefully describe midwifery care outcomes using a common data collection method is needed to provide evidence for determining the continuation of VBAC as part of midwifery care.
Cervical Cancer Screening in Low Resource Settings Using Visual Inspection With Acetic Acid
Authors: Carr Katherine Camacho , Sellors John W.
Published: August 2004

Cervical cancer is one of the leading causes of death for middle‐aged women in the developing world, yet it is almost completely preventable, if precancerous lesions are identified and treated in a timely manner. Cervical cancer screening based on cytologic examination is largely unavailable in developing countries or made available to a small, select group of women in private facilities, maternal child health sites, or family‐planning clinics, missing the age groups at highest risk for precancerous lesions. Visual inspection with acetic acid (VIA) can be used to screen women. It can be done by nurses or midwives with appropriate training. Although still under investigation, research results show that VIA is simple, accurate, cost‐effective, and acceptable to most women. This article reviews the natural history of cervical cancer and important aspects to consider related to cervical cancer screening in low resource settings. The VIA technique is described in detail.
The American College of Nurse‐Midwives' Home‐Based Lifesaving Skills Program: A Review of the Ethiopia Field Test
Authors: CNM Lynn Sibley , Buffington Sandra Tebben , Haileyesus Degafech
Published: August 2004

The Home‐Based Lifesaving Skills program (HBLSS) is a family‐ and community‐focused, competency‐based program that aims to reduce maternal and newborn mortality by increasing access to basic lifesaving measures within the home and community and by decreasing delays in reaching referral facilities where obstetric complications, such as postpartum hemorrhage and newborn asphyxia, can be managed. HBLSS was field tested in rural southern Ethiopia where over 90% of births take place at home with unskilled attendants. The program review assessed 1) the performance of HBLSS‐trained guides; 2) management of postpartum hemorrhage and newborn infection by women, family, and birth attendants; 3) exposure of women and families to HBLSS training; and 4) community support. There was improved performance in management of postpartum hemorrhage, a leading cause of maternal death. Findings for management of newborn infection were less compelling. None of the communities had established reliable emergency transportation. Exposure to HBLSS training in the community was estimated at 38%, and there was strong community support. Organizations incorporating HBLSS into proposals focusing on maternal and newborn health during birth and the immediate postpartum period are encouraged to conduct research necessary to establish the evidence base for this promising new approach.
Continuous Female Companionship During Childbirth: A Crucial Resource in Times of Stress or Calm
Authors: Pascali‐Bonaro Debra , Kroeger Mary
Published: August 2004

Continuous support by a lay woman during labor and delivery facilitates birth, enhances the mother's memory of the experience, strengthens mother‐infant bonding, increases breastfeeding success, and significantly reduces many forms of medical intervention, including cesarean delivery and the use of analgesia, anesthesia, vacuum extraction, and forceps. The contribution of doula care has become increasingly available in industrial countries and is beginning to be adopted in hospitals in underdeveloped countries. Research continues to demonstrate the far‐reaching value of supportive companionship as a corollary to professional health care during birth. Mothers who are at risk because of medical or social factors and those delivering in situations of stress, including disasters, can benefit greatly from labor support.
Newborns in Adverse Conditions: Issues, Challenges, and Interventions
Authors: Davanzo Riccardo
Published: August 2004

Neonatal mortality is intolerably high in developing countries and in situations of crisis or disaster as a result of inequity, poverty, and lack of health care services. A series of effective, low‐cost interventions, based on appropriate technologies can be used to address the main causes of neonatal deaths. Among these interventions, promotion of exclusive breastfeeding and thermal control of the newborn infant are very effective ones. Although the effectiveness of interventions such as kangaroo mother care, newborn resuscitation, and infant massage is not widely recognized, they may have important complementary roles in providing heath care to newborn infants in adverse conditions.
Pediatric Sleep Questionnaire Scores Predict PostOp Improvement on PSG and Behavior
Authors: Garetz Susan L , Weatherly Robert A , Dillon James E , Champine Donna J , Ruzicka Deborah L , Guire Kenneth E , Hodges Elise K , Hervin Ronald D
Published: August 2004

Problem

Children scheduled for adenotonsillectomy frequently also have reversible disruptive behavior disorders (DBD). We examined whether preoperative scores on a sleep questionnaire could assist in predicting postoperative improvement of both polysomnographic variables and disruptive behavior disorders.

Methods

Sixty children, (mean age, 8.3 years) were studied. Behavior assessment, a sleep questionnaire, and nocturnal polysomnography were completed shortly before and 1 year after adenotonsillectomy. Psychiatric evaluation was performed by a child psychiatrist. The Sleep Disordered Breathing Subscale Questionnaire included questions pertaining to symptoms of nocturnal obstruction and behavior items. Obstructive apneas and hypopneas were defined as 2 breaths or longer in duration. Rates of respiratory event‐related arousals plus apneas and hypopneas defined the respiratory disturbance index (RDI).

Results

Severity of SDB generally improved after adeno‐tonsillectomy. DBDs were initially diagnosed in 25 (42%) of subjects and resolved in 12 (48%) of the diagnosed children postoperatively. There were no significant differences noted in the preoperative obstructive apnea index, apnea/hypopnea index, RDI or minimum oxygen saturation (t tests, all P > 0.05) in children whose DBD resolved as compared to those whose DBD did not. There were, however, significant correlations between high scores on the preoperative SDB subscale and postoperative improvement in apnea/hypopnea index (Pearson correlation coefficient r =. 28, P < 0.03), obstructive apnea index (r = 0.32, P < 0.02), and RDI (r = 0.28, P < 0.04). There was also a strong correlation seen between high preoperative questionnaire scores and resolution of DBD (r = 0.28, P < 0.02).

Conclusion

Questionnaires about preoperative symptoms of SDB are predictive of improvement in polysomnographic abnormalities and DBD after adenotonsillectomy. The use of a Pediatric Sleep Questionnaire may be useful in determining which patients have behavioral disorders potentially treatable with surgical intervention.

Significance

Questionnaires may provide a simple, inexpensive method of predicting clinical improvement after adenotonsillectomy in children with SDB and DBDs.

Support

None reported.
Continuous Laryngeal Nerve Monitoring during Thyroidectomy: Does It Reduce the Injury Rate?
Authors: Robertson Matt , Steward David L , Gluckman Jack L
Published: August 2004

Problem

To determine if continuous laryngeal nerve integrity monitoring (NIM) during thyroidectomy is associated with a decreased risk of postoperative recurrent laryngeal nerve (RLN) injury.

Methods

This was a cohort study of 165 patients who underwent thyroidectomy at a resident teaching institution between 1999 and 2002. The control group had 120 nerves at risk (NAR) while the NIM group consisted of 116 NAR. Primary outcome measures included postoperative RLN paralysis, paresis, and total injury rates.

Results

RLN paralysis occurred in 2.54% of NAR in the control group and 0.86% in the NIM group (RR = 0.34, CI95 = 0.04−3.27, P = 0.62). Temporary RLN paresis occurred in 4.24% of NAR in the control group and 3.45% in the NIM group (RR = 0.9, CI95 = 0.23−3.55, P = 0.89). Total RLN injury occurred in 6.78% of NAR in the control group and 4.31% in the NIM group (RR = 0.66, CI95 = 0.21−2.09, P = 0.48). When compared to all other NAR, advanced T‐stage malignancy was associated with a significantly increased risk of RLN paresis (T4 RR = 9.0, CI95 = 2.56−31.67, P = 0.0006; T3+T4 RR = 7.5, CI95 = 2.17−25.86, P = 0.0001) but not paralysis. NIM use did not significantly reduce risk of RLN paresis in the advanced T‐stage subset (T3+T4 RR = 0.36, CI95 = 0.04−3.0, P = 0.59).

Conclusion

There were no statistically significant differences in RLN paralysis, paresis, or total injury rates between control and NIM groups, even in subsets with advanced T‐stage and increased baseline risk. Advanced T‐stage is a significant predictor of RLN paresis in this cohort.

Significance

NIM does not appear necessary in routine thyroidectomy, although it may be considered in patients with T3 and T4 tumors given an increased risk of RLN injury in these patients.

Support

None reported.
Influences of Laryngeal Afferent Blockade on Laryngeal Muscle Activity during Speech
Authors: Saxon Keith G , Poletto Christopher , Kearney Pamela R , Mann Eric , Bidus Kimberly A , Ludlow Christy L
Published: August 2004

Problem

A previous study determined that sensory blockade reduced symptoms in spasmodic dysphonia. The purpose of this study was to determine how laryngeal afferent feedback blockade alters laryngeal muscle activity during speech, to explain this benefit in patients with spasmodic dysphonia.

Methods

We used hooked wire electrodes to record from intrinsic laryngeal muscles (thyroarytenoid, cricothyroid, and posterior cricoarytenoid) during sentence production in subjects with either adductor and abductor spasmodic dysphonia before and after bilateral superior laryngeal nerve blockade with lidocaine. Prior to the block, sensory thresholds were determined for air puff stimuli presented to the mucosa overlying the arytenoid cartilages. Following the block, laryngeal muscle activity during production of the same sentences was recorded again and sensory testing confirmed blockade on both sides. Measures included the mean muscle activity during the first syllable of each sentence, syllable duration, and the pre‐phonatory interval between muscle activity onset and voice onset for the first syllable of each sentence.

Results

No changes occurred in mean muscle activity level following afferent blockade in all 3 muscles. Significant within‐subject reductions were found in the duration of the first syllable of the sentence and in the pre‐phonatory interval between thyroarytenoid muscle activity onset and vocalization onset for speech. The pre‐phonatory interval decreased in 7 of the 8 subjects. No significant changes in pre‐phonatory interval were found in the posterior cricoarytenoid or cricothyroid muscles.

Conclusion

Symptom benefits following a reduction in afferent feedback are not a result of reduced muscle activity level but may reflect changes in central patterning of muscle activity in patients with spasmodic dysphonia.

Significance

These results provide further understanding of the pathophysiology of symptom generation in spasmodic dysphonia.

Support

The research was supported by the National Institute of Neurological Disorders and Stroke, 1 Z01 NS002980‐05.