bluuebunny/crossref_metadata_2025_split huggingface dataset:
A first trimester trisomy 13/trisomy 18 risk algorithm combining fetal nuchal translucency thickness, maternal serum free β‐hCG and PAPP‐A
Authors: Spencer Kevin , Nicolaides Kypros H. 
Published: October 2002

AbstractThis study examines 45 cases of trisomy 13 and 59 cases of trisomy 18 and reports an algorithm to identify pregnancies with a fetus affected by trisomy 13 or 18 by a combination of maternal age fetal nuchal translucency (NT) thickness, and maternal serum free β‐hCG and PAPP‐A at 11–14 weeks of gestation. In this mixed trisomy group the median MoM NT was increased at 2.819, whilst the median MoMs for free β‐hCG and PAPP‐A were reduced at 0.375 and 0.201 respectively. We predict that with the use of the combined trisomy 13 and 18 algorithm and a risk cut‐off of 1 in 150 will for a 0.3% false positive rate allow 95% of these chromosomal defects to be identified at 11–14 weeks. Such algorithms will enhance existing first trimester screening algorithms for trisomy 21. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis of trisomy 21 by i(21q): a rare case of fetoplacental chromosomal discrepancy
Authors: Gilardi J. L. , Perrotin F. , Paillet C. , Blesson S. , Cave H. , Briault S. , Moraine C. 
Published: October 2002

AbstractObjectiveA study was conducted to explain the mechanism of an unusual discrepancy between short‐ and long‐term culture examination methods of chorionic villus sampling (CVS).MethodIn a 29‐year‐old Caucasian woman, transabdominal CVS was carried out at 12 weeks of gestation. Non‐mosaic karyotype 46,XX,i(21q) was found on long‐term CVS culture but number and morphology of chromosomes were normal on short‐term culture, amniocyte culture, hygroma colli fluid and fetal fibroblast.ResultsChromosomal aberration probably appeared after the trophoblast cell line differentiation, four days after fertilization, by means of a 21 centromere misdivision and formation of a i(21q) with secondary positive selection of the 46,XX,i(21q) cell line and loss of the 46,XX in the fetus.ConclusionThe restricted number of cases with this type of discrepancy limits the possibility of drawing generalised conclusions. In case of discrepancy, we recommend confirmation by amniocentesis or by fetal blood combined with sonographic examination to provide a more definitive diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis of Crigler–Najjar syndrome type I by single‐strand conformation polymorphism (SSCP)
Authors: Francoual Jeanne , Trioche Pascale , Mokrani Chahnez , Seboui Hassen , Khrouf Naïma , Chalas Jacqueline , Clement Marina , Capel Liliane , Tachdjian Gérard , Labrune Philippe 
Published: October 2002

AbstractCrigler–Najjar syndrome type I (CN‐I) is a rare and severe inherited disorder of bilirubin metabolism, caused by the total deficiency of bilirubin‐UDP‐glucuronosyltransferase (UGT) activity. Enzymatic diagnosis cannot be performed in chorionic villi or amniocytes as UGT is not active in these tissues. The cloning of the UGT1 gene and the identification of disease‐causing mutations have led to the possibility of performing DNA‐based diagnosis. Here we report DNA‐based prenatal diagnosis of CN‐I in two Tunisian families in whom CN‐I patients were diagnosed. As we had previously shown that CN‐I was, in Tunisia, associated with homozygosity for the Q357R mutation within the UGT1 gene, we were able to detect this mutation in both families and to show that it was easily recognized by single‐strand conformation polymorphism (SSCP) analysis. In both cases, SSCP analysis of fetal DNA showed that the fetus was heterozygous for the Q357R mutation. In one family, the pregnancy was carried to term and a healthy baby was born, whereas, in the other family, the pregnancy is still continuing. Thus the prenatal diagnosis of CN‐I is possible, provided disease‐causing mutations have been identified. SSCP analysis of DNA prepared either from amniocytes or from chorionic villi is a simple, reliable and fast method for prenatal diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.
Using a qualitative research method for building a software maintenance methodology
Authors: Polo Macario , Piattini Mario , Ruiz Francisco 
Published: October 2002

AbstractThis article explains our experience of using Action Research to develop a software maintenance methodology involving two organizations: a group of university researchers and a software services organization. The concept of ‘methodology’ comprises a wide set of elements whose identification, definition and integration is not a trivial task, due to the magnitude of the project and to the different nature of the organizations. The use of Action Research was a key factor in the progress of the research and has been essential in the adoption of the methodology within the software services organization. Copyright © 2002 John Wiley & Sons, Ltd.
CD++: a toolkit to develop DEVS models
Authors: Wainer Gabriel 
Published: October 2002

AbstractThe features of a toolkit for modeling and simulation based on the DEVS formalism are presented. The tool is built as a set of independent software pieces running on different platforms. Not only are the main characteristics of the environment presented, a focus on its use is also considered by inclusion of application examples for a variety of problems. Many models can be defined in an automated fashion, simplifying the construction of new models and easing their verification. The use of this formal approach has allowed the development of safe and cost‐effective simulations, significantly reducing development time. Copyright © 2002 John Wiley & Sons, Ltd.
Primary Hyperparathyroidism Revisited in Menopausal Women with Serum Calcium in the Upper Normal Range at Population‐based Screening 8 Years Ago
Authors: Lundgren Ewa , Hagström Emil G. , Lundin Jonas , Winnerbäck Kajsa , Roos Johanna , Ljunghall Sverker , Rastad Jonas 
Published: October 2002

Population‐based screening showed 2.1% prevalence of primary hyperparathyroidism (pHPT) in postmenopausal women. Individuals with total serum (s)‐calcium levels of 2.55 mmol/L or more at screening were diagnosed with pHPT when subsequent analysis supported inappropriately elevated intact parathormone (PTH) levels in relation to even normal s‐calcium levels. The arbitrary diagnostic criteria were validated by parathyroidectomy. Herein we reinvestigated biochemical signs of pHPT in women not diagnosed with pHPT due to s‐calcium 2.50 to 2.54 mmol/L (group A, n = 160) at screening or due to appropriate PTH levels on two occasions after screening (group B, n = 70). Altogether, 99 women in group A and 47 in group B underwent reinvestigation 8.8 years after screening when they were 65 to 84 years old. The s‐calcium levels averaged 2.56 mmol/L and had increased in group A (mean 0.04 mmol/L) and decreased in group B (mean 0.05 mmol/L). A total of 48 and 18 females (48%, 38%), respectively, met the previously validated criteria of pHPT. Altogether 21% of them were hypercalcemic (range 2.60–3.12 mmol/L). Subgroup analysis showed that PTH had not increased with time (n = 47) and that atherogenic blood lipids, but not glucose levels, were similar in pHPT patients and matched controls (n = 37). Assuming the existence of pHPT already at screening, the prevalence of pHPT could be adjusted to 3.4%. Even the most liberal diagnostic criteria utilized at pHPT screening seemed to underdiagnose the disease by inefficient cutoff limits for s‐calcium and PTH. Because one‐fifth of the women with pHPT progressed to hypercalcemia, long‐term follow‐up is advocated for those with s‐calcium in the upper normal range.
Clinical value of early cleavage embryo
Authors: Tsai Y.C , Chung M.T , Sung Y.H , Tsai T.F , Tsai Y.T , Lin L.Y 
Published: October 2002

AbstractObjective: This study was undertaken to see if embryo transfer containing early cleavage embryos resulted in better clinical pregnancy rate. Method: The treatment outcomes of IVF‐ET were retrospectively reviewed. Out of 258 transfer cycles, 160 cycles contained no early cleavage embryos (Group I) and 98 cycles contained at least one early cleavage embryo (Group II). The definition of early cleavage embryo is the presence of two blastomeres 24–26 h after insemination. The implantation rate, clinical pregnancy rate were compared between two groups. Student's t‐test and the Mann–Whitney U‐test were used for continuous variables, and the Chi‐squared (χ2) test was used for binary variables. Differences were considered statistically significant at P<0.05. Result: The implantation rate and clinical pregnancy rate were 11.6% and 25.6% in Group I, 18.6% and 38.8% in Group II (P<0.05). Conclusion: Early cleavage embryos possess greater implantation potential. Embryo transfer containing early cleavage embryos had a better clinical pregnancy rate.
Interleukin‐6 and interleukin‐1 receptor antagonist in amniotic fluid and cord blood in patients with pre‐term, premature rupture of the membranes
Authors: Fukuda H. , Masuzaki H. , Ishimaru T. 
Published: October 2002

AbstractObjective: We investigated the role of interleukin (IL)‐6 and IL‐1 receptor antagonist (IL‐1ra) in pre‐term premature rupture of the membranes (PROM). Method: Amniotic fluid samples were collected from 10 patients with pre‐term PROM (group 1a), 13 patients undergoing genetic amniocentesis (group 2), seven patients with normal vaginal delivery (group 3a), and 11 patients with elective cesarean section (group 4a). Umbilical venous blood was collected from nine cases of pre‐term PROM (group 1b), 19 cases of normal delivery (group 3b) and nine cases of elective cesarean section (group 4b). Results: The concentration of IL‐6 in the amniotic fluid in group 1a was significantly higher than in group 2 (P<0.001), and that in group 3a was significantly higher than in group 4a (P<0.001). The concentration of IL‐1ra in amniotic fluid in group 1a was significantly higher than in group 2 (P<0.001). The concentrations of IL‐6 in umbilical venous blood were not significant among the groups. The concentration of IL‐1ra in umbilical venous blood in group 1b was significantly higher than in group 3b (P<0.05) and group 4b (P<0.05). Conclusions: High concentrations of amniotic fluid IL‐6 present in pre‐term PROM, are indicative of intrauterine inflammation, probably due to sub‐clinical infection. The high concentrations of IL‐1ra in amniotic fluid and umbilical venous blood suggest the possibility that the presence of this anti‐inflammatory cytokine serves to prevent the development of overt inflammation.
An exploratory analysis of new competencies: a resource based view perspective
Authors: Coates Theresa Taylor , McDermott Christopher M 
Published: October 2002

AbstractThe resource based view (RBV) theory of the firm widely acknowledges that capabilities that are unique and are important for achieving sustained competitive advantage. It has been argued in the manufacturing literature that manufacturing facilities, technology and policies are important to gain performance. However, little has been done to examine the capabilities from a resource based perspective. Nor has there been an exploration in how firms develop and leverage new capabilities. The literature also tends to neglect how complex and often intertwined these capabilities are within the firms. This study addresses this gap in the literature by examining the successful development of new resources and competencies that were created when Analog Devices developed an emerging technology. The paper is exploratory and identifies the new competencies and Analog Devices’ ability to capitalize upon them.
Cellular manufacturing for small businesses: key cultural factors that impact the conversion process
Authors: Yauch Charlene A , Steudel Harold J 
Published: October 2002

AbstractCompanies converting to cellular manufacturing (CM) often struggle with implementation and achieve results that are less than anticipated. The existing body of CM research, with its strong emphasis on technical aspects, does not provide practitioners with the assistance needed for successful implementation. Since organizational culture is a strong barrier to change, this research aimed to reveal how culture impacts the CM conversion process. Two exploratory case studies were conducted at small manufacturing companies leading to the identification of eight key cultural factors that impact CM conversion.
Inheritance of symmetry for positive solutions of semilinear elliptic boundary value problems
Authors: Kawohl Bernd , Sweers Guido 
Published: October 2002

The paper addresses symmetry results for positive solutions of semilinear elliptic differential equations on a class of non-convex symmetrical domains. An example in two dimensions is the star of David. The moving plane method just shows that solutions coincide on three alternate corners of the star. We will show that the solution is symmetric with respect to remaining reflections, that is, the solution will have the full symmetry. To obtain such type of result, even for domains in higher dimensions, we use a variant of the sliding-method and the maximum principle for domains with small measure.

Résumé
Des résultats concernant la symétrie des solutions positives d' équations elliptiques semilinéaires sur une classe de domaines symétriques nonconvexes sont établis. Un exemple en dimension deux est l' étoile de David. La méthode des plans mobiles dans sa forme habituelle permet de montrer le symétrie de telles solutions seulement par rapport à trois axes. Nous sommes en mesure de prouver la symétrie par rapport au centre et donc la symétrie totale. Pour obtenir ce type de résultat, même pour des domaines en dimension supérieure à deux, nous utilisons la méthode des balayages et le principe du maximum pour les domaines de mesure petite.
A nonexistence result for Yamabe type problems on thin annuli
Authors: Ben Ayed Mohamed , El Mehdi Khalil , Hammami Mokhless 
Published: October 2002

Given any constant

C>0

, we show that there exists

ε_0>0

such that for any

ε<ε_0

, the problem

P_{ɛ}: - \Delta u_{ɛ} = u_{ɛ}^{\left(n + 2\right)/ \left(n - 2\right)},u_{ɛ} > 0

in

A_{ɛ}

;

u_{ɛ} = 0

on

\partial A_{ɛ}

, has no solution

u_ε

, whose energy,

∫_{A_ε}|∇u_ε|^2

, is less than

C

, where

A_ε

is a ringshaped open set in

ℝ^{n}

and

n⩾4

.

Résumé

Etant donné une constante positive

C

arbitraire, nous montrons qu'il existe

ε_0>0

tel que pour tout

ε<ε_0

, le problème

p_{ɛ}: - \Delta u_{ɛ} = u_{ɛ}^{\left(n + 2\right)/ \left(n - 2\right)},u_{ɛ} > 0

dans

A_{ɛ}

;

u_{ɛ} = 0

sur

\partial A_{ɛ}

, ne possède pas de solution

u_ε

dont l'energie,

∫_{A_ε}|∇u_ε|^2

, est plus petite que

C

, où

A_ε

est un ouvert de

ℝ^{n}

ayant la forme d'un anneau et

n⩾4

.
Biosynthetic response and mechanical properties of articular cartilage after injurious compression
Authors: Kurz Bodo , Jin Moonsoo , Patwari Parth , Cheng Debbie M. , Lark Michael W. , Grodzinsky Alan J. 
Published: October 2002

AbstractTraumatic joint injury is known to produce osteoarthritic degeneration of articular cartilage. To study the effects of injurious compression on the degradation and repair of cartilage in vitro, we developed a model that allows strain and strain rate‐controlled loading of cartilage explants. The influence of strain rate on both cartilage matrix biosynthesis and mechanical properties was assessed after single injurious compressions. Loading with a strain rate of 0.01 s−1 to a final strain of 50% resulted in no measured effect on the cells or on the extracellular matrix, although peak stresses reached levels of about 12 MPa. However, compression with strain rates of 0.1 and 1 s−1 caused peak stresses of approximately 18 and 24 MPa, respectively, and resulted in significant decreases in both proteoglycan and total protein biosynthesis. The mechanical properties of the explants (compressive and shear stiffness) were also reduced with increasing strain rate. Additionally, cell viability decreased with increasing strain rate, and the remaining viable cells lost their ability to exhibit an increase in biosynthesis in response to low‐amplitude dynamic mechanical stimulation. This latter decrease in reparative response was most dramatic in the tissue compressed at the highest strain rates. We conclude that strain rate (like peak stress or strain) is an important parameter in defining mechanical injury, and that cartilage injuriously compressed at high strain rates can lose its characteristic anabolic response to low‐amplitude cyclic mechanical loading. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Integrative cartilage repair: adhesive strength is correlated with collagen deposition
Authors: Dimicco Michael A. , Sah Robert L. 
Published: October 2002

AbstractProcedures to repair focal articular cartilage defects often result in poor integration between the host cartilage and the graft tissue, and this may be related to the lack of matrix deposition and the death of chondrocytes near a cut cartilage surface. The objective of this study was to determine if cartilage repair was related to deposition of newly synthesized collagen. The mechanical integration that occurred between two live adult bovine cartilage blocks cultured in partial apposition for two weeks was correlated with [3H]proline incorporation, a measure of protein synthesis, of which more than 66% was accounted for by collagen. A similar level of mechanical integration occurred in sample pairs consisting of a live and killed cartilage block, and this adhesive strength was also correlated with [3H]proline deposition into both the live and the killed blocks. In these samples, the [3H]proline deposited into the killed cartilage appeared to originate from chondrocytes in the live cartilage, since live cells were not detected in the killed cartilage block by either viability staining or [35S]sulfate incorporation. These results suggest a mechanism of integrative cartilage repair in which live chondrocytes within cartilage secrete matrix molecules that are components of a collagen network, and subsequent deposition of these molecules near the repair interface contributes to functional integration. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
BMP‐12 gene transfer augmentation of lacerated tendon repair
Authors: Lou Jueren , Tu Yizheng , Burns Meghan , Silva Matthew. J. , Manske Paul 
Published: October 2002

AbstractBone morphogenetic protein (BMP) 12 is a recently discovered member of the human BMP family. It is the human homolog of mouse growth/differentiation factor (GDF)‐7. Previously we reported that injection of mesenchymal progenitor cells transferred with the BMP‐12 gene into the muscles of nude mice induced tendon‐like tissue formation. In this study, we further investigated the effect of BMP‐12 gene transfer on tendon cells. We observed that adenovirus mediated in vitro BMP‐12 gene transfer into chicken tendon cells increased type I collagen synthesis. No change in alkaline phosphatase activity was observed following BMP‐12 gene transfer. We also determined that BMP‐12 gene transfer into a complete tendon laceration chicken model resulted in a two‐fold increase of tensile strength and stiffness of repaired tendons, indicating improved tendon healing in vivo. We conclude that BMP‐12 gene transfer is a promising procedure for improving the tendon repair process. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Controlled‐release of IGF‐I and TGF‐β1 in a photopolymerizing hydrogel for cartilage tissue engineering
Authors: Elisseeff Jennifer , McIntosh Winnette , Fu Karen , Blunk Torsten , Langer Robert 
Published: October 2002

AbstractPhotopolymerizing hydrogel systems provide a method to encapsulate cells and implant materials in a minimally invasive manner. Controlled release of growth factors in the hydrogels may enhance the ability to engineer tissues. IGF‐I and TGF‐β were loaded in PLGA microspheres using a double emulsion technique. 125 ng and 200 pg of active IGF‐I and TGF‐β, respectively, as measured by ELISA, were released over 15 days. The growth factor containing microspheres were photoencapsulated with bovine articular chondrocytes in PEO‐based hydrogels and incubated in vitro for two weeks. Statistically significant changes in glycosaminoglycan (GAG) production compared to control gels either without microspheres or with blank spheres were observed after a 14 day incubation with IGF‐I and IGF‐I/TGF‐β microspheres combined, with a maximum density of 8.41 ± 2.5% wet weight GAG. Total collagen density was low and decreased with the IGF‐I/TGF‐β microspheres after two weeks incubation, but otherwise remained unchanged in all other experimental groups. Cell content increased 10‐fold to 0.18 ± 0.056 × 106 cells/mg wet weight and extracellular matrix (ECM) staining by H&E increased in hydrogels with IGF‐I/TGF‐β microspheres. In conclusion, photoencapsulation of microspheres in PEO‐based hydrogels provides a method to deliver molecules such as growth factors in porous hydrogel systems. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Measurement of material elastic constants of trabecular bone: a micromechanical analytic study using a 1 GHz acoustic microscope
Authors: Jørgensen C. S. , Kundu T. 
Published: October 2002

AbstractThe propagation speed (C) of surface acoustic waves (SAW), e.g. Rayleigh (R‐waves) and longitudinal lateral waves (L‐waves), the latter being the surface manifestation of the longitudinal waves, strongly reflect mechanical properties of materials. In view of an increasing interest in ultrasonic methodology in the field of bone biomechanics, we tested the hypothesis that both R‐ and L‐waves can be excited in trabecular bone using an acoustic microscope at 1 GHz and that their speeds (CR and CL) can be extracted from V(z)‐curves, i.e. plots of lens output voltage as a function of the lens focal point position with respect to the specimen surface. In accordance with V(z)‐curves theoretically synthesized on the basis of incident field theory, experimental curves for canine femoral trabecular bone showed evidence of both R‐ and L‐waves in almost all regions of recording. The measured CR ranged between 1.93 and 2.07 km/s (mean ± SD.: 2.00 ± 0.06 km/s) and the CL ranged between 2.33 and 4.33 km/s (3.37 ± 0.61 km/s). Knowledge of both speeds allowed computation of a number of material constants by means of simple theory of elasticity and assumptions of the material density. We found values of Poisson ratio (v) ranging from 0.14 to 0.32 (0.23 ± 0.07), Young's modulus (E) from 15 to 22.8 GPa (19.9 ± 2.5 GPa) and the shear modulus (G) from 7.6 to 8.9 GPa (8.4 ± 0.5 GPa). Anisotropy in the trabecular bone material was clearly detected at the micrometer level. In conclusion, the V(z)‐curve method was successfully used to determine the distribution of material elastic constants of trabecular bone with micrometer resolution. © 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.