bluuebunny/crossref_metadata_2025 huggingface dataset:
Initial repair strengths of two methods for acute medial collateral ligament injuries of the elbow
Authors: Pichora James E. , Furukawa Keizo , Ferreira Louis M. , Faber Kenneth J. , Johnson James A. , King Graham J.W.
Published: February 2007

The purposes of this study were to compare the initial repair strength of the medial collateral ligament (MCL) of the elbow using trans‐osseous sutures and suture anchor methods and to determine the effect of repair pretensioning. Twelve, fresh‐frozen upper extremities (66 ± 5 years) were mounted in a valgus‐loading system. MCL repairs were performed using trans‐osseous suture and suture anchor methods with 20 N or 40 N pretensioning. A cyclic (0.5 Hz), valgus 40 N load was applied 12 cm distal to the elbow axis of flexion. The load was increased by 10 N every 200 cycles until a length increase of 5 mm or catastrophic failure of the repair occurred. Repairs pretensioned with 40 N endured a significantly higher number of cycles and failed at higher loads than those pretensioned with 20 N (p < 0.05). No difference was found in the cycles or load to failure between trans‐osseous sutures and suture anchors (p > 0.05). A higher magnitude of pretensioning of MCL repairs was found to increase initial repair strength suggesting that pretensioning should be performed clinically. Despite the comparable failure loads of the trans‐osseous suture and suture anchor methods, the failure mechanism differed between the two techniques. The suture anchors usually failed catastrophically when the sutures broke as they passed through the anchor eyelet, while the trans‐osseous sutures gradually elongated to the defined failure length by stretching and sliding through the ligament. The use of different suture anchors, suture sizes, or suture materials would likely influence the findings of this study and should be considered when applying these findings clinically. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:612–616, 2007
Distinct roles of bone morphogenetic proteins in osteogenic differentiation of mesenchymal stem cells
Authors: Luu Hue H. , Song Wen‐Xin , Luo Xiaoji , Manning David , Luo Jinyong , Deng Zhong‐Liang , Sharff Katie A. , Montag Anthony G. , Haydon Rex C. , He Tong‐Chuan
Published: February 2007

Efficacious bone regeneration could revolutionize the clinical management of many bone and musculoskeletal disorders. Bone morphogenetic proteins (BMPs) can regulate the differentiation of mesenchymal stem cells into cartilage, bone, tendon/ligament, and fat lineages. Early data documented the osteogenic potential of rhBMP2 and rhBMP7/OP‐1. However, prior to this work that summarized several of our recent studies, no comprehensive analysis had been undertaken to characterize relative osteogenic activity of all BMPs. Using recombinant adenoviruses expressing 14 BMPs, we have demonstrated that, besides BMP2 and BMP7, BMP6 and BMP9 exhibit the highest osteogenic activity both in vitro and in vivo. We further demonstrated that several BMPs may exert synergistic effect on osteogenic differentiation, and that osteogenic BMPs produce a distinct set of molecular fingerprints during osteogenic differentiation. The reported work should expand our current understanding of BMP functions during osteogenic differentiation. It is conceivable that osteogenic BMPs (i.e., BMP2, 4, 6, 7, and 9) may be used to formulate synergistic pairs among themselves and/or with other less osteogenic BMPs for efficacious bone regeneration in clinical settings. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:665–677, 2007
In vivo medial and lateral tibial loads during dynamic and high flexion activities
Authors: Zhao Dong , Banks Scott A. , D'Lima Darryl D. , Colwell Clifford W. , Fregly Benjamin J.
Published: February 2007

Though asymmetric loading between the medial and lateral compartments of total knee replacements may contribute to implant loosening and failure, the in vivo contact force distribution during dynamic daily activities remains unknown. This study reports in vivo medial and lateral contact forces experienced by a well‐aligned knee implant for a variety of activities. In vivo implant motion and total axial load data were collected from a single knee replacement patient performing treadmill gait (hands resting on handlebars), step up/down, lunge, and kneel activities. In vivo motion was measured using video fluoroscopy, while in vivo axial loads were collected simultaneously using an instrumented tibial component. An elastic foundation contact model employing linear and nonlinear polyethylene material properties was constructed to calculate medial and lateral contact forces based on the measured kinematics, total axial loads, and centers of pressure. For all activities, the predicted medial and lateral contact forces were insensitive to the selected material model. The percentage of medial to total contact force ranged from 18 to 60 for gait, 47 to 65 for step up/down, and 55 to 60 for kneel and lunge. At maximum load during the motion cycle, medial force was 1.2 BW for gait and 2.0 BW for step up/down, while the corresponding lateral forces were 1.0 and 1.5 BW, respectively. At mean load in the final static pose, medial force was 0.2 BW for kneel and 0.9 BW for lunge, with corresponding lateral forces of 0.1 and 0.7 BW, respectively. For this patient, a constant load split of 55% medial–45% lateral during loaded activity would be a reasonable approximation for these test conditions. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:593–602, 2007
From experimental research to an on‐farm tool for participatory monitoring and evaluation: an assessment of soil erosion risk in organic olive orchards
Authors: Milgroom J. , Gómez J. A. , Soriano M. A. , Fereres E.
Published: February 2007

The conservation of soil in agricultural systems prone to erosion can occur as a result of conscientious soil management practices by individual farmers. Although soil is one of the world's most important and highly threatened natural resources, and should be among the top priorities in organic agriculture, soil management practices and the effect of those practices on erosion risk are rarely, if ever, taken into account as a part of organic certification. In order to fulfil the need for a tool to monitor soil erosion in organic olive orchards in Southern Spain, we have developed a methodology that assesses erosion risk through an easy to use, illustrated erosion risk field manual to be used by farmers, inspectors for certifying agencies and field technicians. The methodology developed for the assessment is based on a simplified version of the Revised Universal Soil Loss Equation (RUSLE), combined with an evaluation of key visual symptoms of soil erosion. The methodology is described, and the results from use of the assessment in the field and in workshops with farmers are presented. The potential for use of the methodology for other crops and in other regions is discussed and also the future relevance of farmer‐oriented tools in the context of changing regulations within the common agricultural policy of the European Union. Copyright © 2007 John Wiley & Sons, Ltd.
Workplace isolation: Exploring the construct and its measurement
Authors: Marshall Greg W. , Michaels Charles E. , Mulki Jay P.
Published: February 2007

Virtual offices are a growing trend in today's work environment and are expected to influence marketing roles dramatically, especially selling. These conditions may lead to perceptions of isolation, both socially and organizationally. Workplace isolation is a twodimensional construct that represents individuals' perceptions of isolation from others at work and includes perceived isolation from both colleagues and from the company's support network. This article reports the results of a four‐sample study to develop and validate a selfreport scale for measuring the two facets of workplace isolation. The scale's usefulness for future research and management applications are discussed. © 2007 Wiley Periodicals, Inc.
Determining the antecedents and consequences of donor‐perceived relationship quality—A dimensional qualitative research approach
Authors: Shabbir Haseeb , Palihawadana Dayananda , Thwaites Des
Published: February 2007

It is generally accepted that an understanding of quality conceptualizations is instrumental in the design and development of customer care programs. This study applies the dimensional qualitative research approach to develop a conceptual model, which demonstrates the antecedents and consequences of donor‐perceived relationship quality. This model shows that relationship benefits, service quality, trust, commitment, and satisfaction are the key antecedents of donor‐perceived relationship quality. Relationship benefits, service quality, and trust are also modeled as cognitive in nature, whereas commitment and satisfaction are modeled as affective variables. The model also highlights donor loyalty and positive word‐of‐mouth communications as the central consequences of donor‐perceived quality. The model gives rise to a useful research agenda for fund‐raising professionals. © 2007 Wiley Periodicals, Inc.
Nondigital tissue replantation and microsurgical spare part utilization in mutilated hands: Case reports and review
Authors: Nasir Serdar , Aydin Mustafa Asim , Gülgönen Ayan
Published: February 2007

Five cases with microsurgical utilization of spare parts from unreplantable amputated segments are presented. Besides, nondigital composite tissue replantations are firstly reported in hand. They all resulted in satisfactory outcomes compared to alternative treatments without any donor site morbidity. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Perfusion, viability, and pedicle dependence in acute and delayed rat island skin flaps
Authors: Komorowska‐Timek Ewa , Timek Tomasz A. , Brady Sandra , Buncke Harry J.
Published: February 2007

Purpose: Although surgical delay phenomenon has been widely investigated, its pathophysiology has not been fully elucidated. Methods: In 25 Spraque–Dawley rats, an 8 × 8 cm2 epigastric skin flap consisting of 4 vertical zones A through D (farthest from vascular pedicle) was outlined. All animals were perfused twice with colored fluorescent microspheres: immediately before and after flap elevation (Acute, n = 10) and before and after pedicle ligation on POD 8 (Delayed, n = 15). Results: After acute flap elevation, peripheral perfusion dropped significantly in zone C (0.29 ± 0.01 vs. 0.19 ± 0.04 ml g−1 min−1; P < 0.01) and zone D (0.33 ± 0.09 vs 0.01 ± 0.01 ml g−1 min−1; P < 0.01), while global flap perfusion remained unchanged. Total and regional blood flow did not change in the Delayed group after pedicle ligation. Conclusions: Elevation of a pedicled flap caused significant decrease in distal flap perfusion while maintaining proximal and total flap perfusion. Eight‐day delay was adequate to establish sufficient flap perfusion independent of the vascular pedicle. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Intramolecular hydrogen bonding of novel o‐hydroxythioacetophenones and related compounds evaluated by deuterium isotope effects on 13C chemical shifts
Authors: Nguyen Trung Thanh , Le Thach Ngoc , Duus Fritz , Hansen Bjarke K. V. , Hansen Poul Erik
Published: February 2007

A new class of compounds, the 2‐hydroxythioacetophenones, and related compounds have recently been synthesized. The hydrogen‐bond system has been characterized by NMR chemical shifts and deuterium isotope effects on these as well as by DFT calculations. Use of solid‐state 13C NMR has enabled measurements of the intrinsic deuterium isotope effects of the most abundant tautomer of β‐thioxoketones. The compounds show very interesting long‐range deuterium isotope effects on the thiocarbonyl carbon. The intramolecular hydrogen bonds of o‐hydroxythioacetophenones are found to be slightly stronger than those of the corresponding acetophenones. The reactivity and stability of the compounds can be related to hydrogen bonding and to the presence of electron donating substituents. Copyright © 2007 John Wiley & Sons, Ltd.
Structure elucidation and complete NMR spectral assignments of a novel sesquiterpene glycoside from Ixeris sonchifolia
Authors: Ye Guan , Fang Jing‐jing , Fan Ming‐song , Huang Cheng‐gang
Published: February 2007

A novel sesquiterpene glycoside was isolated from the whole plant of Ixeris sonchifolia. The structure was established as 1(10)E‐4Z‐3α‐hydroxy‐germacra‐1(10),4,11(13)‐trien‐6, 12‐olide‐14‐O‐β‐D‐glucopyranoside (1) on the basis of spectroscopic techniques and chemical analysis. Copyright © 2007 John Wiley & Sons, Ltd.
G2/M checkpoint gene expression in developing germ cells
Authors: Hasthorpe Suzanne , Tainton Kellie , Peart Melissa , Roeszler Kelly N. , Bell Katrina M. , Lusby Patricia E. , Hutson John M. , Tymms Martin J.
Published: February 2007

Cell cycle progression is prevented by signal transduction pathways known as checkpoints which are activated in response to replication interference and DNA damage. We cloned a G2/M cell cycle phase‐related checkpoint gene from a neonatal mouse testis cDNA library which was identified as mouse claspin, a proposed adaptor protein for Chk1. As part of a study on germ cell differentiation we examined the expression of the checkpoint gene, Chk1, and claspin at 12.5 and 14.5 days post coitum (dpc) and in the post‐natal phase. Chk1 mRNA expression increased from 12.5 to 14.5 dpc in female gonads and was strong in males at both time points. Claspin however, was not detected until 14.5 dpc. This suggests there may be some dissociation of claspin expression from Chk1 in fetal germ cell development. Chk1 and claspin expression was also studied in testis over the first 3 days following birth, when apoptosis regulates germ stem cell number. We modulated checkpoint‐related gene expression in testis using the anti‐metabolite, 5‐fluorouracil, resulting in increased apoptosis and upregulation of Chk1 (P < 0.0001) and Cdc2 (P < 0.02) mRNA. Although we do not fully understand the role checkpoint gene expression has during mammalian germ cell development this report is the first to show the expression of checkpoint‐related genes in early mammalian germ cells. Mol. Reprod. Dev. 74: 531–538, 2007. © 2007 Wiley‐Liss, Inc.
Differential expression and localization of four connexins in the ovary of the ayu (Plecoglossus Altivelis)
Authors: Yamamoto Yoji , Yoshizaki Goro , Takeuchi Toshio , Soyano Kiyoshi , Itoh Fuminari , Patiño Reynaldo
Published: February 2007

The post‐vitellogenic oocytes of teleost fish are generally unresponsive to maturation‐inducing hormone (MIH) until a luteinizing hormone (LH) surge stimulates sensitivity via the acquisition of oocyte‐maturational competence (OMC). Heterologous gap junctions (GJs) between granulosa cells and the oocyte have been previously implicated in the regulation of oocyte maturation in various vertebrate species. Although heterologous GJ are present in ovarian follicles of ayu (Plecoglossus altivelis), their role in maturation remains unclear. In the present study, we cloned and characterized complementary DNAs for GJ protein connexin (Cx), and examined the expression pattern of Cx messenger RNAs in the ayu ovary. Four Cx cDNAs with predicted molecular masses of 32.1 (Cx32.1), 34.9 (Cx34.9), 44.1 (Cx44.1), and 44.2 (Cx44.2) kDa, respectively, were cloned. Northern blot analysis revealed that the levels of Cx44.1 and Cx44.2 transcripts were similar during the vitellogenic and ovulatory stages. Cx32.1 transcripts were more abundant during the vitellogenic stage, but their levels declined thereafter. Cx34.9 transcript levels increased during the vitellogenic stage and remained high during the acquisition of OMC. In situ hybridization revealed that Cx44.1 and Cx44.2 signals were restricted to the oocyte, whereas the Cx32.1 and Cx34.9 signals were detected in both cellular fractions. Furthermore, a dye‐transfer assay revealed the presence of functional GJs between the oocytes and follicle cells. These results suggest that Cx34.9 contributes to the formation of heterologous GJs between oocytes and granulosa cells. Moreover, GJs formed by Cx34.9 may function during the LH‐dependent acquisition of OMC and the MIH‐dependent resumption of meiosis in ayu. Mol. Reprod. Dev. 74: 1113–1123, 2007. © 2007 Wiley‐Liss, Inc.
Vitrification devices affect structural and molecular status of in vitro matured ovine oocytes
Authors: Succu S. , Leoni G.G. , Bebbere D. , Berlinguer F. , Mossa F. , Bogliolo L. , Madeddu M. , Ledda S. , Naitana S.
Published: February 2007

We evaluated the effect of three different cryodevices on membrane integrity, tubulin polymerization, maturation promoting factor (MPF) activity and developmental competence of in vitro matured (IVM) ovine oocytes. IVM oocytes were exposed during 3 min to 7.5% DMSO and 7.5% ethylene glycol (EG) in TCM199 and 25 sec to 0.5 M sucrose, 16.5% DMSO and 16.5% EG, loaded in open pulled straws (OPS), cryoloops (CL) or cryotops (CT) and immersed into liquid nitrogen. Untreated (CTR) or exposed to vitrification solutions but not cryopreserved (EXP) oocytes were used as controls. After warming, double fluorescent staining evidenced a lower membrane integrity in vitrified groups compared to the controls (P < 0.01). After in vitro fertilization and culture OPS and CL groups evidenced a lower cleavage rate than CT and controls (P < 0.01) while blastocysts were obtained only in CL and EXP, at a lower rate than CTR (P < 0.01). All vitrified groups showed alterations in spindle conformation, which were partially recovered in OPS and CT groups. MPF activity was lower in treated compared to CTR and CT showed the lowest value (P < 0.01). After 2 hr culture MPF activity was restored in all groups except CT. Parthenogenetic activation was higher in treated compared to CTR and CT evidenced the highest value. Our results indicate that cryodevice influences not only the ability to survive cryopreservation but is also associated with molecular alterations which affect developmental competence. Mol. Reprod. Dev. 74: 1337–1344, 2007. © 2007 Wiley‐Liss, Inc.
Dynamics of DNA‐demethylation in early mouse and rat embryos developed in vivo and in vitro
Authors: Zaitseva Ioulia , Zaitsev Sergei , Alenina Natalia , Bader Michael , Krivokharchenko Alexander
Published: February 2007

Virtually all mammalian species including mouse, rat, pig, cow, and human, but not sheep and rabbit, undergo genome‐wide epigenetic reprogramming by demethylation of the male pronucleus in early preimplantation development. In this study, we have investigated and compared the dynamics of DNA demethylation in preimplantation mouse and rat embryos by immunofluorescence staining with an antibody against 5‐methylcytosine. We performed for the first time a detailed analysis of demethylation kinetics of early rat preimplantation embryos and have shown that active demethylation of the male pronucleus in rat zygotes proceeds with a slower kinetic than that in mouse embryos. Using dated mating we found that equally methylated male and female pronuclei were observed at 3 hr after copulation for mouse and 6 hr for rat embryos. However, a difference in methylation levels between male and female pronuclei could be observed already at 8 hr after copulation in mouse and 10 hr in rat. At 10 hr after copulation, mouse male pronuclei were completely demethylated, whereas rat zygotes at 16 hr after copulation still exhibited detectable methylation of the male pronucleus. In addition in both species, a higher DNA methylation level was found in embryos developed in vitro compared to in vivo, which may be one of the possible reasons for the described aberrations in embryonic gene expression after in vitro embryo manipulation and culture. Mol. Reprod. Dev. 74: 1255–1261, 2007. © 2007 Wiley‐Liss, Inc.
Possible involvement of CD81 in acrosome reaction of sperm in mice
Authors: Tanigawa Maya , Miyamoto Kiyoko , Kobayashi Satoshi , Sato Masahiro , Akutsu Hidenori , Okabe Masaru , Mekada Eisuke , Sakakibara Keiichi , Miyado Mami , Umezawa Akihiro , Miyado Kenji
Published: February 2007

Tetraspanin CD81 is closely homologous in amino acid sequence with CD9. CD9 is well known to be involved in sperm–egg fusion, and CD81 has also been reported to be involved in membrane fusion events. However, the function of CD81 as well as that of CD9 in membrane fusion remains unclear. Here, we report that disruption of the mouse CD81 gene led to a reduction in the fecundity of female mice, and CD81−/− eggs had impaired ability to fuse with sperm. Furthermore, we demonstrated that when CD81−/− eggs were incubated with sperm, some of the sperm that penetrated into the perivitelline space of CD81−/− eggs had not yet undergone the acrosome reaction, indicating that the impaired fusibility of CD81−/− eggs may be in part caused by failure of the acrosome reaction of sperm. In addition, we showed that CD81 was highly expressed in granulosa cells, somatic cells that surround oocytes. Our observations suggest that there is an interaction between sperm and CD81 on somatic cells surrounding eggs before the direct interaction of sperm and eggs. Our results may provide new clues for clarifying the cellular mechanism of the acrosome reaction, which is required for sperm–egg fusion. Mol. Reprod. Dev. 75: 150–155, 2008. © 2007 Wiley‐Liss, Inc.
Confined blood chimerism in monochorionic dizygous (MCDZ) twins
Authors: Walker Susan P. , Meagher Simon , White Susan M.
Published: February 2007

Objective

To present the risk factors, prenatal and postnatal implications of monochorionic dyzygotic twinning.

Methods

We present a case of monochorionic twins diagnosed on first‐trimester ultrasound following a 2‐embryo transfer in vitro fertilisation pregnancy. Postnatal buccal smears performed as part of a twin research study revealed the twins to be dizygous, and DNA testing on peripheral blood lymphocytes confirmed the presence of blood chimerism.

Results

Despite the monochorionic placentation, buccal swabs revealed discordant results for all four microsatellite loci tested, consistent with dizygosity. Zygosity testing on peripheral blood lymphocytes revealed that, of the nine DNA microsatellite loci tested, three had all four parental alleles represented. This result was concordant between the twins. The diagnosis of blood chimerism was thus confirmed, presumably due to the inter‐twin vascular anastomoses of the monochorionic placenta.

Conclusion

Monochorionic dizygous twinning is rare, but appears to be more common after assisted reproduction. It is presumed that outer cell mass fusion may occur when two embryos are replaced in close proximity. These pregnancies are not only at risk for the usual complications of monochorionicity, but also have the potential to be heterokaryotypic. Postnatally, the twins may have long‐term blood chimerism. Copyright © 2007 John Wiley & Sons, Ltd.
Microphthalmia with linear skin defects (MLS) syndrome evaluated by prenatal karyotyping, FISH and array comparative genomic hybridization
Authors: Cain Colyn Cargile , Saul Daniel , Attanasio Lisa , Oehler Erin , Hamosh Ada , Blakemore Karin , Stetten Gail
Published: February 2007

Objective

To explore the utility of comparative genomic hybridization to BAC arrays (array CGH) for prenatal diagnosis of microphthalmia and linear skin defects syndrome.

Methods

We used karyotype analysis, FISH and array CGH to investigate an X;Y translocation. Replication studies were done on cultured amniocytes and lymphoblasts.

Results

We describe a severe case of MLS syndrome that presented prenatally with multiple anomalies including cystic hygroma, microphthalmia, intrauterine growth restriction and a complex congenital heart defect. Cytogenetic analysis of amniocytes revealed an unbalanced de novo translocation between chromosomes X and Y [karyotype 46,X,der(X)t(X;Y)(p22.3;q11.2).ish der(X)(DXZ1+,DMD+,KAL−,STS−,SRY−),22q11.2 (Tuple1 × 2)]. MLS diagnosis was made at birth and the prenatal karyotype was confirmed. Replication studies showed the derivative X chromosome was the inactive X. Array CGH confirmed the X and Y imbalances seen in the karyotype and also showed twelve BACs in the MLS region were deleted as a result of the translocation. FISH with BAC clones verified the array findings and placed the X breakpoint in Xp22.2, resulting in the amended karyotype, 46,X,der(X)t(X;Y)(p22.2;q11.2).ish der(X)(DXZ1+,DMD+,KAL−,STS−,SRY−),22q11.2(Tuple1 × 2) arr cgh Xp22.33p22.2(LLNOYCO3M15D10 →GS1‐590J6)× 1,Yq11.222q23(RP11‐20H21→RP11‐79J10)× 1.

Conclusion

The sensitivity of array CGH was valuable in detecting monosomy of the MLS critical region. Array CGH should be considered for the prenatal diagnosis of this syndrome. Copyright © 2007 John Wiley & Sons, Ltd.
Complete discrepancy between QF‐PCR analysis of uncultured villi and karyotyping of cultured cells in the prenatal diagnosis of trisomy 21 in three CVS
Authors: Waters Jonathan J. , Mann Kathy , Grimsley Lee , Ogilvie Caroline Mackie , Donaghue Celia , Staples Leonie , Hills Alison , Adams Tracey , Wilson Christine
Published: February 2007

Objective

To investigate complete discrepancies in the prenatal diagnosis of trisomy 21 between QF‐PCR analysis of uncultured villi and karyotyping of cultured cells in three chorion villus samples.

Methods

Clinical details were obtained from all three patients. Follow‐up studies were undertaken where possible by evaluation of chromosome 21 copy number with QF‐PCR, interphase FISH, MLPA and karyotyping, and by post‐mortem examination.

Results

Case 1: severe oligohydramnios and microcephaly on scan. QF‐PCR: trisomy 21; MLPA: trisomy 21; cultured karyotype: 46,XY[48]. Placental and fetal tissue results and post‐mortem examination indicated a euploid fetus with trisomy 21 mosaicism confined to the placenta. Case 2: Down screen risk 1:16; NT = 4.4 mm; absent nasal bone (Caucasian mother). QF‐PCR: disomy 21; cultured karyotype: 47,XY,+ 21[23]. Neck thickening noted at delivery—post‐mortem refused, no fetal tissue available. Placental tissue indicated mosaicism for trisomy 21. Case 3: Down screen risk 1:91; NT = 6.7 mm. QF‐PCR: disomy 21; cultured karyotype: 46,XX,der(21;21)(q10;q10)[60]. No follow‐up possible. PCR genotyping of cultured cells confirmed sample identity in all three cases. Chromosome 21 markers observed by PCR were biallelic in all three cases, indicating that a mitotic error could account for the presence of the abnormal cell lines in each case.

Conclusion

QF‐PCR analysis of uncultured villi and cultured karyotyping may rarely show complete discrepancy in the prediction of fetal trisomy 21 in CVS. Within‐biopsy sample mosaicism, together with the testing of different cell populations, provide an explanation for these results. Practical ways to minimise the risk of such discrepancy are proposed. Copyright © 2007 John Wiley & Sons, Ltd.
Free fetal DNA in maternal plasma in anembryonic pregnancies: confirmation that the origin is the trophoblast
Authors: Alberry M. , Maddocks D. , Jones M. , Abdel Hadi M. , Abdel‐Fattah S. , Avent N. , Soothill P. W.
Published: February 2007

Objective

To test the hypothesis that free fetal DNA (ffDNA) circulating in maternal plasma originates mainly from the placenta we studied ffDNA levels in anembryonic pregnancies.

Methods

Maternal blood samples were collected from 15 normal first‐trimester pregnancies in which fetal sex was subsequently determined and nine patients with a diagnosis of anembryonic gestation (AG). The Y chromosome DYS14 gene was quantified by real‐time quantitative PCR (RT‐PCR) for the determination of fetal sex in both plasma and chorionic tissue samples. Fetal sex in chorionic tissue samples was also determined using quantitative fluorescence PCR (QF‐PCR).

Results

The correct sex result was obtained from maternal plasma in all. Four AG pregnancies were female (DYS14 negative) results. In five of the AG cases, the chorionic tissue was found to be male (by both QF‐PCR and RT‐PCR which agreed) and positive male signal was found in maternal plasma by RT‐PCR. There was no statistical difference between median free fetal DNA concentration in plasma between the AG male cases (148.3 GE/mL) and controls (145.8 GE/mL).

Conclusion

Since ffDNA levels are normal in pregnancies without a fetus, the data support the hypothesis that the trophoblastic cells are the major source ffDNA in maternal plasma. Copyright © 2007 John Wiley & Sons, Ltd.
Statins and fracture risk. A systematic review
Authors: Toh Sengwee , Hernández‐Díaz Sonia
Published: February 2007

Purpose

To summarize current evidence on statin use and fracture risk and to explore potential sources of heterogeneity among study results.

Methods

A computerized search was conducted on MEDLINE, EMBASE, and the Cochrane databases using the keywords HMG‐CoA reductase inhibitor, osteoporosis, and fractures. A meta‐analysis was performed to summarize results of studies identified.

Results

Statin use was associated with a 23% lower fracture risk (OR = 0.77, 95%CI: 0.66–0.90). An effect of statins was found in case‐control (OR = 0.62, 0.45–0.85, n = 6) and cohort (OR = 0.77, 0.59–1.00, n = 8) studies, but not in post hoc analyses of randomized trials (OR = 1.03, 0.91–1.16, n = 4). A reduced risk with statin use was found for fractures of the hip (OR = 0.58, 0.46–0.74, n = 16), spine (OR = 0.65, 0.48–0.88, n = 8) and other sites (OR = 0.77, 0.60–1.00, n = 7), and both in women (OR = 0.80, 0.66–0.96, n = 11) and men (OR = 0.62, 0.36–1.08, n = 3). Among the observational studies that also evaluated the effect of other lipid‐lowering drugs, no reduced fracture risk was found for these agents (OR = 0.96, 0.85–1.09, n = 10). The test for heterogeneity was significant for study results of statin use versus no‐use (p < 0.01). Meta‐regression analyses suggested that study design might partly account for the heterogeneity. There was an indication of publication bias by examining Begg's plot, although Egger's test was not significant (p = 0.13).

Conclusions

Current evidence does not support an effect of statins in preventing fractures given (i) the lack of association in randomized trials, (ii) the heterogeneity among observational studies, (iii) the potential residual confounding, and (iv) the potential publication bias. Copyright © 2007 John Wiley & Sons, Ltd.
Clinical interest: a study of the influence on general practitioners' prescribing
Authors: Hansen Dorte Gilså , Dybdahl Torben , Jarbøl Dorte , Vach Werner
Published: February 2007

Purpose

To analyse the association between general practitioners' clinical interest and prescribing rates in four clinical areas: dyspepsia, depression, headache and diabetes.

Methods

Data concerning general practitioners' prescribing during 2004 were retrieved from a pharmacy database and linked with data from a physician questionnaire and the National Health Insurance Register. To counterbalance differences in practice populations all 1‐year prevalences of prescribing were standardised according to age and gender. Participants were asked ‘To what extent do you find the following areas interesting from a professional point‐of‐ view?’ Four rating categories were used. The association between clinical interest and standardised prescribing rates was investigated using logistic regression, the Kruskal‐Wallis test and a trend test.

Results

A total of 68 (72%) single‐handed general practitioners representative of the total group completed the questionnaire. We observed a two‐fold ratio between the 90% and the 10% percentiles of the 1‐year prevalences of antisecretory drugs, antidepressants, migraine drugs as well as anti‐diabetics. The variation in prescribing of antidepressant and antisecretory drugs was far above chance level. No significant association with clinical interest could, however, be observed for any of the four clinical areas.

Conclusion

General practitioners' prescribing of the four classes of medical drugs varied considerably. However, only part of this variation was based on chance. This study did not confirm our hypothesis that general practitioners' level of clinical interest in one area corresponds with their prescribing of drugs used within that area. Copyright © 2007 John Wiley & Sons, Ltd.
Inadequacy of fluconazole dosing in patients with candidemia based on Infectious Diseases Society of America (IDSA) guidelines
Authors: Garey Kevin W. , Pai Manjunath P. , Suda Katie J. , Turpin Robin S. , Rege Milind D. , Mingo Dana E. , Bearden David T.
Published: February 2007

Introduction

Based on Infectious Diseases Society of America (IDSA) guidelines, inappropriate fluconazole therapy in patients with candidemia is defined as an empiric dose <6 mg/kg/d, <12 mg/kg/d after Candida glabrata identification, or continued fluconazole use after identification of Candida krusei. However, the extent to which inappropriate antifungal therapy is due to improper dosing or drug selection has not been well investigated. The objectives of this study were to assess the incidence of inappropriate fluconazole therapy in patients with candidemia and to identify variables associated with inappropriate therapy.

Methods

Retrospective cohort study from four medical centers of hospitalized patients with candidemia prescribed fluconazole. Appropriateness of fluconazole dosages (adjusted for renal dysfunction) was assessed at the time of symptom onset and after Candida identification.

Results

Patients (206) were identified. Sixty‐one of 112 (55%) patients who were given empiric therapy received an initial dose of fluconazole <6 mg/kg. After identification of the Candida species, 97 of 206 (47%) patients received inadequate fluconazole therapy based on IDSA guideline recommendations due to a fluconazole dose <12 mg/kg after isolation of C. glabrata (12%), continued use of fluconazole after isolation of C. krusei (3%), or a dose <6 mg/kg for all other Candida species (32%).Using multivariate logistic regression, increased weight in 1‐kg increments (OR: 1.02; p = 0.0142) and a creatinine clearance (CRCL) >50 ml/minute (OR: 3.17; p = 0.0003) were associated with increased risk of inadequate fluconazole therapy.

Conclusion

A high prevalence of suboptimal dosing of fluconazole given empirically or after Candida species identification was documented. Increased weight and CRCL were significant predictors of inadequate fluconazole doses. Copyright © 2007 John Wiley & Sons, Ltd.
Fetal growth and congenital malformations
Authors: Nikkilä A. , Källén B. , Maršál K.
Published: February 2007

Objectives

To ascertain whether the risk for congenital malformations is increased in pregnancies with deviating fetal growth, i.e. in those in which the estimated date of delivery (EDD) was postponed more than 1 week at the second‐trimester ultrasound fetometry scan, or those suspected of intrauterine growth restriction at routine ultrasound fetometry in the third trimester.

Methods

The study period was 1994–2003. We used the Swedish Medical Birth Register to identify pregnancies with appropriate data (n = 605 845). A regional ultrasound database consisting of 73 092 pregnancies was used for more detailed data and analysis of the third‐trimester fetal growth. The number of congenital malformations was ascertained from three national health registers.

Results

We found a moderately increased risk for any malformation in the group of fetuses in which the EDD was postponed > 1 week. The strongest effect was seen for chromosome anomalies and central nervous system malformations, including neural tube defects. In the third trimester, an increased risk for fetal malformations was found in asymmetrically vs. symmetrically growth‐restricted fetuses, perhaps more strongly when adjustment of the EDD had been done at the dating scan.

Conclusions

Fetuses in which the EDD differs between that calculated by the last menstrual period and that calculated by second‐trimester ultrasound measurement seem to have an increased risk for congenital malformations, including chromosomal anomalies. A targeted ultrasound examination for malformation screening might be recommended for this group. A similar policy might be recommended when intrauterine growth restriction, especially of the asymmetrical type, is suspected later in pregnancy. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Clinical and ultrasound estimation of birth weight prior to induction of labor at term
Authors: Peregrine E. , O'Brien P. , Jauniaux E.
Published: February 2007

Objectives

To assess and compare the accuracy of clinical and sonographic fetal weight estimation in predicting birth weight prior to induction of labor.

Methods

In a prospective study of 262 women immediately prior to induction of labor, the fetal weight was estimated clinically by both the doctor (DR EFW) and the woman herself (WM EFW). A transabdominal scan was then performed to estimate the fetal weight sonographically using two different formulae—Shepard (SHEP EFW) and Hadlock (HAD EFW). The four estimated fetal weights were compared with the actual birth weight.

Results

The mean percentage error was − 1.9 ± 9.3% for DR EFW, − 3.4 ± 12.6% for WM EFW, − 2.3 ± 11.6% for SHEP EFW and − 7.6 ± 10.6% for HAD EFW. All four EFWs were significantly different from birth weight (t = − 4.7, − 5.5, − 3.5 and − 11.4, respectively, all P < 0.01). The corresponding proportion of the EFWs which were within 10% of birth weight were 71%, 59%, 62% and 42%, respectively. The sensitivity and specificity of detecting a fetus weighing < 3000 g were 56% and 98% for DR EFW, 90% and 89% for WM EFW, 93% and 83% for SHEP EFW and 100% and 76% for HAD EFW. The corresponding values for detecting a fetus weighing > 4000 g were 16% and 99%, 29% and 96%, 48% and 92% and 40% and 94%, respectively.

Conclusions

Although, in general, clinical estimates of birth weight perform favorably compared with ultrasonographic estimates, ultrasound immediately prior to labor is more accurate at predicting the low‐ or high‐birth‐weight fetus. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Superior balance of weatherability and impact performance with acrylic‐capped vinyl siding
Authors: Szamborski Gene
Published: February 2007

Vinyl siding, particularly in darker colors, has to be durable and be able to retain most of its original color when exposed outdoors. As the color palette for vinyl siding has been expanding and more and more colors are being offered to the homeowner, the need exists to improve color hold. A new acrylic capstock polymer, based on core‐shell technology, which can be coextruded onto vinyl siding, has been shown to provide excellent color retention, with good processability, impact and impact retention, and suitable gloss. The properties of this new capstock polymer are compared to other choices for capping vinyl siding. J. VINYL ADDIT. TECHNOL., 13:26–30, 2007. © 2007 Society of Plastics Engineers.
Kaliumpolysulfide: [K(THF)]2S6 und [K2(THF)]S9
Authors: Dornhaus Franz , Bolte Michael , Wagner Matthias , Lerner Hans‐Wolfram
Published: February 2007

Potassiumpolysulfides: [K(THF)]2S6 and [K2(THF)]S9

The polysulfide [K2(THF)]S9 is accessible from reaction of S8 with [KSPPh2(BH3)]. Degradation reaction of S8 with [KPPh2(BH3)] results in [K(THF)]2S6. X‐ray quality crystals of [K(THF)]2S6 (orthorhombic, Pbca) and of [K2(THF)]S9 (orthorhombic, Pbcm) are obtained each from THF / diethyl ether solution at ambient temperature. According to the result of the X‐ray structural analysis, [K(THF)]2S6 and [K2(THF)]S9 contain a S6‐ and S9‐zigzag chain. The conformation of both polysulfide anions is all‐transoid.
Synthesis and Crystal Structures of Octahedral Metal Complexes containing the New Dianion [PhP(Se,O)Se‐Se(O,Se)PPh]2−
Authors: Shi Weifeng , Zhang Le , Shafaei‐Fallah Maryam , Rothenberger Alexander
Published: February 2007

The synthesis and structures of three new compounds are reported. [Mg2{PhP(Se,O)Se‐Se(O,Se)PPh}2(thf)7(H2O)3] (1), [Mg{PhP(Se,O)Se‐Se(O,Se)PPh}(thf)3(H2O)] (2), and [Mn{PhP(Se,O)Se‐Se(O,Se)PPh}(thf)3(H2O)] (3) were prepared by treatment of Woollins' reagent [PhP(Se)(μ‐Se)]2 with the corresponding hydrated metal acetates.
Zur Elektronenstruktur metallorganischer Komplexe der f‐Elemente. 65 Erstmalige Beobachtung des linearen Dichroismus bei einem homoleptischen metallorganischen π‐Komplex der f‐Elemente: Tris(η5‐tetramethylcyclopenta‐dienyl)neodym(III)
Authors: Amberger Hanns‐Dieter , Reddmann Hauke
Published: February 2007

Electronic Structures of Organometallic Complexes of f Elements. 65 First Observation of Linear Dichroism of a Homoleptic Organometallic π Complex of f Elements: Tris(η5‐tetramethylcyclopentadienyl)neodymium(III)

The absorption spectrum of a powder sample of pseudo (Ψ) trigonal planar Nd(η5‐C5Me4H)3 (1) has been measured at room temperature and ca. 40 K, respectively, and the linear dichroism spectra of σ‐ and π‐type of an oriented single crystal at ambient temperature and 77 K. Neglecting the signals of the C–H combination vibrations and overtones extracted from the absorption spectrum of La(η5‐C5Me4H)3 (2), the observed polarization properties of the remaining f‐f transitions allowed the derivation of a truncated crystal field splitting pattern. The free parameters of a phenomenological Hamiltonian were fitted to this pattern leading to a reduced r.m.s. deviation of 16.1 cm−1 for 38 assignments. The temperature dependence of the paramagnetic susceptibility of 1 was calculated, making use of the crystal field energies and wavefunctions of the fit. Introducing an orbital reduction factor of 0.98, calculated values of 1 agree well with the experimental ones of Ψ trigonal planar Nd(C5H4tBu)3.
Monomeric Homoleptic (2‐Pyridylmethyl)(tert‐butyldimethylsilyl)amido Complexes of the Divalent Metals Mg, Mn, Fe, Co, and Zn
Authors: Koch Christian , Malassa Astrid , Agthe Christine , Görls Helmar , Biedermann Ralf , Krautscheid Harald , Westerhausen Matthias
Published: February 2007

The transamination reaction of M[N(SiMe3)2]2 with (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amine yields the corresponding homoleptic metal bis[(2‐pyridylmethyl)(tert‐butyldimethylsilyl)amides] of Mg (1), Mn (2), Fe (3), Co (4) and Zn (5). All these compounds crystallize from hexane isotypic in the space group C2/c. From toluene the zinc derivative precipitates as toluene solvate 5·toluene. The molecular structures of these compounds are very similar with large NMN angles to the amide nitrogen atoms with NMN values of 148° (1) and 150° (5) for the diamagnetic compounds and 156° for the paramagnetic derivatives 2 and 3. The Co derivative 4 displays a rather small NCoN angle of 142°. Different synthetic routes have been explored for compound 3 which is also available via the metallation reaction of bis(2,4,6‐trimethylphenyl)iron with (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amine and via the metathesis reaction of lithium (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amide with [(thf)2FeCl2]. In course of the metathesis reaction, an equimolar amount of lithium (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amide and [(thf)2FeCl2] yields heteroleptic (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amido iron(II) chloride (6) which crystallizes as a centrosymmetric dimeric molecule. The oxidative C‐C coupling reaction of 5 with Sn[N(SiMe3)2]2 leads to the formation of tin(II) 1,2‐bis(2‐pyridyl)‐1,2‐bis(tert‐butyldimethylsilylamido)ethane, tin metal and Zn[N(SiMe3)2]2.
Copper(II) Complexes of ω‐Hydroxy‐Functionalized N‐Salicylidenehydrazides show pH‐Controlled Switching between Dicationic Dimers and Neutral One‐Dimensional Coordination Polymers
Authors: Roth Arne , Buchholz Axel , Plass Winfried
Published: February 2007

New copper(II) complexes of the hydrazone ligands H2salhyhb, H2salhyhp, and H2salhyhh, derived from salicylaldehyde and ω‐hydroxy carbonic acid hydrazides, have been synthesized and physically characterized. Two fundamental structures were found in solid state depending on the pH‐value of the reaction solution. Acidic conditions lead to the formation of the di‐μ‐phenoxo‐bridged dicationic complex dimers [{Cu(Hsalhyhb)}2]2+ (1a), [{Cu(Hsalhyhp)}2]2+ (2a), and [{Cu(Hsalhyhh)}2]2+ (3a), isolated as perchlorate salts. The dimeric complexes show strong antiferromagnetic coupling with J = −399 (1a), −410 (2a), and −311 cm−1 (3a). Higher pH‐values resulted in the aggregation of neutral copper ligand fragments to the one‐dimensional coordination polymers [{Cu(salhyhb)}n] (1b), [{Cu(salhyhp)}n] (2b), and [{Cu(salhyhh)}n] (3b). 3b has been examined by means of X‐ray crystallography and represents the first example of a structurally characterized neutral copper(II) N‐salicylidenehydrazide complex without additional ligands. The magnetic interactions in the polymers are also antiferromagnetic with J = −125 (1b), −136 (2b), and −148 cm−1 (3b), but strongly reduced compared to the corresponding dimeric complexes. The two basic structure types can be reversibly interconverted simply by pH‐control.
Formation and Crystal Structure of the Salt (IC(PPh3)2)2I[I3]·(I2)2 with a new Polyiodide Chain
Authors: Petz Wolfgang , Heimann Samuel , Öxler Florian , Neumüller Bernhard
Published: February 2007

The reaction of the carbodiphosphorane Ph3P=C=PPh3 (1) with MeI in the presence of iodine gives the oxidation product (IC(PPh3)2)2I[I3]·(I2)2 (2). In the solid state dimeric units linked by indefinite ···I−···I2···I3−···I2···I−··· chains are found. An additional I···I contact between the cation and the I2 molecule is formed, amounting to 359.23(5) pm. 2 crystallizes in the monoclinic space group P2/c, with the unit cell dimensions a = 2053.9(1), b = 1011.4(1), c = 1889.8(1) pm; β = 105.21(1)° and Z = 4.
Structural Investigations and Thermal Behaviour of Mercury(II) Sulfito Complexes
Authors: Weil Matthias , Breitinger Dietrich K. , Liehr Günther , Zürbig Jürgen
Published: February 2007

The crystal structures of (NH4)[HgSO3Cl] (1) and of (NH4)2[Hg(SO3)2] (2) were determined from single crystal diffractometer data sets. 1: 22 °C, Pnma, Z = 4, a = 15.430(3), b = 5.525(1), c = 6.679(1) Å, R(F) = 0.0256, Rw(F2) = 0.0642 (all 1056 unique reflections). 2: −108 °C, P212121, Z = 4, a = 6.2240(4), b = 9.3908(6), c = 13.6110(8) Å, R(F) = 0.0179, Rw(F2) = 0.0493 (all 2699 unique reflections). The structure of 1 contains bent Cl‐Hg‐SO3 entities (site symmetry m; d(Hg‐Cl) = 2.3403(13) Å, d(Hg‐S) = 2.3636(12) Å, ∠(Cl‐Hg‐S) = 164.51(5)°, d(S‐O) 2×1.458(3) Å, 1.468(4) Å, ${\bar d}\rm (S-O)$= 1.461Å) linked to undulated ribbons parallel to the b‐axis by intermolecular secondary bonds SO···Hg (d(O···Hg) = 2×2.595(3) Å). These ribbons in turn aggregate to layers around the bc‐plane. The layers are stacked along the a‐axis with interlayer distances of a/2. The structure of 2 is made up of O3S‐Hg‐SO3 moieties (d(Hg‐S) = 2.3935(7), 2.3935(8) Å; ∠(Hg‐S‐Hg) = 174.41(3)°; ${\bar d}\rm (S-O)$ = 1.474Å), that are linked to ribbons parallel to the a axis by coordination of Hg to three remote O atoms (2.801(4) < d(Hg‐O) < 2.844(3) Å). Adjacent ribbons are joined together by an additional Hg‐O contact of 2.733(3) Å, leading to a three‐dimensional anionic framework. Both crystal structures are stabilised by disordered NH4+ cations, placed between the anionic layers or in the vacancies of the framework, via moderate hydrogen bonding interactions N‐H···O with donor‐acceptor distances ranging from 2.8 to 3.2Å. 1 and 2 were further characterised by thermal analysis (TG, DSC). They start to decompose at temperatures above 130 °C.
Synthese und Kristallstruktur des Lewis‐Säure/Base‐Addukts AlCl3·C3N3Cl3
Authors: Tragl Sonja , Gibson Katharina , Meyer H.‐Jürgen
Published: February 2007

Synthesis and Crystal Structure of the Lewis Acid‐Base Adduct AlCl3·C3N3Cl3

The reaction between cyanuric chloride (C3N3Cl3) and the strong Lewis acid AlCl3 yielded colorless crystals of the adduct AlCl3·C3N3Cl3. The crystal structure was determined by single crystal X‐ray diffraction at room temperature and was solved in the space group $P{\bar1}$ with Z = 4, a = 7.3802(7) Å, b = 9.688(1) Å, c = 16.272(2) Å, α = 72.80(1)°, β = 89.97(1)°, γ = 87.23(1)°, and V = 1110.0(2) Å3. In the crystal structure, AlCl3 is closely associated to the triazine ring with Al–N distances of 2.042(3) Å and 2.067(4) Å, respectively. The AlCl3·C3N3Cl3 units are connected with each other via intermolecular N···Cl donor–acceptor interactions, forming tape‐like arrangements in the ac‐plane, with tapes running parallel to the a‐axis.