bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitric oxide agents impair insulin-mediated signal transduction in rat skeletal muscle
Authors: Badal Simone , Brown Paul D , Ragoobirsingh Dalip
Published: May 2006

Background

Evidence demonstrates that exogenously administered nitric oxide (NO) can induce insulin resistance in skeletal muscle. We have investigated the modulatory effects of two NO donors, S-nitroso-N-acetyl-D, L-penicillamine (SNAP) and S-nitrosoglutathione (GSNO) on the early events in insulin signaling in rat skeletal myocytes.

Results

Skeletal muscle cells from 6–8 week old Sprague-Dawley rats were treated with SNAP or GSNO (25 ng/ml) in the presence or absence of glucose (25 mM) and insulin (100 nM). Cellular insulin receptor-β levels and tyrosine phosphorylation in IRS-1 were significantly reduced, while serine phosphorylation in IRS-1 was significantly increased in these cells, when compared to the insulin-stimulated control. Reversal to near normal levels was achieved using the NO scavenger, 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl 3-oxide (carboxy-PTIO).

Conclusion

These data suggest that NO is a potent modulator of insulin-mediated signal transduction and may play a significant role in the pathogenesis of type 2 diabetes mellitus.
Improving the specificity of high-throughput ortholog prediction
Authors: Fulton Debra L , Li Yvonne Y , Laird Matthew R , Horsman Benjamin GS , Roche Fiona M , Brinkman Fiona SL
Published: May 2006

Background

Orthologs (genes that have diverged after a speciation event) tend to have similar function, and so their prediction has become an important component of comparative genomics and genome annotation. The gold standard phylogenetic analysis approach of comparing available organismal phylogeny to gene phylogeny is not easily automated for genome-wide analysis; therefore, ortholog prediction for large genome-scale datasets is typically performed using a reciprocal-best-BLAST-hits (RBH) approach. One problem with RBH is that it will incorrectly predict a paralog as an ortholog when incomplete genome sequences or gene loss is involved. In addition, there is an increasing interest in identifying orthologs most likely to have retained similar function.

Results

To address these issues, we present here a high-throughput computational method named Ortholuge that further evaluates previously predicted orthologs (including those predicted using an RBH-based approach) – identifying which orthologs most closely reflect species divergence and may more likely have similar function. Ortholuge analyzes phylogenetic distance ratios involving two comparison species and an outgroup species, noting cases where relative gene divergence is atypical. It also identifies some cases of gene duplication after species divergence. Through simulations of incomplete genome data/gene loss, we show that the vast majority of genes falsely predicted as orthologs by an RBH-based method can be identified. Ortholuge was then used to estimate the number of false-positives (predominantly paralogs) in selected RBH-predicted ortholog datasets, identifying approximately 10% paralogs in a eukaryotic data set (mouse-rat comparison) and 5% in a bacterial data set (Pseudomonas putida – Pseudomonas syringae species comparison). Higher quality (more precise) datasets of orthologs, which we term "ssd-orthologs" (s upporting-s pecies-d ivergence-orthologs), were also constructed. These datasets, as well as Ortholuge software that may be used to characterize other species' datasets, are available at http://www.pathogenomics.ca/ortholuge/ (software under GNU General Public License).

Conclusion

The Ortholuge method reported here appears to significantly improve the specificity (precision) of high-throughput ortholog prediction for both bacterial and eukaryotic species. This method, and its associated software, will aid those performing various comparative genomics-based analyses, such as the prediction of conserved regulatory elements upstream of orthologous genes.
Demonstration of two novel methods for predicting functional siRNA efficiency
Authors: Jia Peilin , Shi Tieliu , Cai Yudong , Li Yixue
Published: May 2006

Background

siRNAs are small RNAs that serve as sequence determinants during the gene silencing process called RNA interference (RNAi). It is well know that siRNA efficiency is crucial in the RNAi pathway, and the siRNA efficiency for targeting different sites of a specific gene varies greatly. Therefore, there is high demand for reliable siRNAs prediction tools and for the design methods able to pick up high silencing potential siRNAs.

Results

In this paper, two systems have been established for the prediction of functional siRNAs: (1) a statistical model based on sequence information and (2) a machine learning model based on three features of siRNA sequences, namely binary description, thermodynamic profile and nucleotide composition. Both of the two methods show high performance on the two datasets we have constructed for training the model.

Conclusion

Both of the two methods studied in this paper emphasize the importance of sequence information for the prediction of functional siRNAs. The way of denoting a bio-sequence by binary system in mathematical language might be helpful in other analysis work associated with fixed-length bio-sequence.
Bartonella quintana coinfection with Mycobacterium aviumcomplex and CMV in an AIDS patient: case presentation
Authors: Rovery Clarisse , Rolain Jean Marc , Lepidi Hubert , Zandotti Christine , Moreau Jacques , Brouqui Philippe
Published: May 2006

Background

As a greater number of HIV-infected patients survive despite profound immunodepression due to medical progress, we face complex infection with multiple agents in AIDS-patients.

Case presentation

We report the case of an AIDS patient with a primary clinical presentation suggestive of bacillary angiomatosis. We also found in cutaneous lesions Mycobacterium avium complex and cytomegalovirus.

Conclusion

This clinical case illustrates the possibility of multiple coinfections in AIDS patients and the need to be exhaustive in evaluating infectious diseases in severely immunocompromised patients.
Rational antibiotic use in China: lessons learnt through introducing surgeons to Australian guidelines
Authors: Zhang Yan , Harvey Ken
Published: May 2006

Background

World-wide concern about increasing antibiotic resistance has focused attention on strategies to improve antibiotic use. This research adapted Australian best-practice guidelines on the prophylactic use of antibiotics in surgery to a Beijing teaching hospital and then used them as a quality assessment and improvement tool, supplemented by educational interventions. Qualitative data about factors influencing antibiotic use was also obtained.

Methods

Australian and international guideline materials were amalgamated with the help of Chinese experts. Antibiotics prescribed for surgical prophylaxis in 60 consecutive patients undergoing clean or clean-contaminated surgery (120 total) were then compared with guideline recommendations in three phases; a pre-intervention period from June to August, 2002, an intervention period from June to August 2003 and post-intervention period from September to November 2003. During the intervention phase, feedback about prescriptions not in accord with the guideline was discussed with around 25 prescribers every two weeks. In addition, local factors influencing antibiotic use were explored with 13 junior surgeons and 8 high level informants.

Results

While agreement was reached on the principles of antibiotic surgical prophylaxis there was no consensus on detail. Of 180 patients undergoing clean surgery throughout all phases of the study, antibiotic prophylaxis was administered to 78% compared to 98% of the 180 patients undergoing clean-contaminated surgery. Second and third generation cephalosporin antibiotics predominated in both low-risk clean and clean-contaminated operations. The timing of prophylaxis was correct in virtually all patients. The duration of prophylaxis was less than 24 hours in 96% of patients undergoing clean surgery compared to only 62% of patients undergoing clean-contaminated surgery. The intervention produced no improvement in the duration of prophylaxis nor the overuse and inappropriate choice of unnecessary broad-spectrum and expensive drugs. Interviews and focus groups revealed that an important explanation for the latter problem was Chinese government policy which expected hospitals to support themselves largely through the sale of drugs.

Conclusion

Improving antibiotic use in China will require hospital funding reform, more authoritative best-practice guidelines, and hospital authorities embracing quality improvement.
Self-assembly of a Surfactant-encapsulated Polyoxometalate Mediated by Coordination of Metal Ions
Authors: Zhang Hui , Li Haolong , Li Wen , Wu Lixin
Published: May 2006

The introduction of functional 4-(4-pyridylvinylene)phenyl group into surfactant encapsulated polyoxometalate complex (SEC) can form a terminal-group-modified organic/inorganic hybrid complex, SEC-1. This complex, which acts as basic building blocks, can aggregate into size controlled nanoensembles mediated by the addition and coordination of metal ions (ZnCl2) in organic phase.
Non-catalytic Anti-Markovnikov Phenol Alkylation with Supercritical Water
Authors: Sato Takafumi , Ishiyama Yasuyoshi , Itoh Naotsugu
Published: May 2006

The anti-Markovnikov alkylation of phenol with tert-butyl alcohol could be achieved without catalyst in supercritical water at 673 K. The dehydration of tert-butyl alcohol gave isobutene and was followed by the reaction with phenol to form 2-isobutylphenol as an anti-Markovnikov product, 2-tert-butylphenol and 4-tert-butylphenol. The hydroxy group probably participated in the anti-Markovnikov alkylation and the increase in water density enhanced the formation of 2-isobutylphenol as well as 4-tert-butylphenol.
Paricalcitol [19-Nor-1,25-(OH)2D2] in the Treatment of Experimental Renal Bone Disease
Authors: Jokihaara Jarkko , Pörsti Ilkka , Pajamäki Ilari , Vuohelainen Tuomo , Jolma Pasi , Kööbi Peeter , Kalliovalkama Jarkko , Niemelä Onni , Kannus Pekka , Sievänen Harri , Järvinen Teppo LN
Published: May 2006

Paricalcitol is a less hypercalcemic vitamin D analog that has been shown to suppress secondary hyperparathyroidism and to prevent the associated histomorphometric changes in bone. In this study, we show that paricalcitol also ameliorates the renal insufficiency-induced loss of bone mineral and the mechanical competence of bone.

Introduction: Renal bone disease is a common consequence of chronic renal insufficiency and the associated secondary hyperparathyroidism (SH). Paricalcitol [19-nor-1,25(OH)2D2] has been shown to ameliorate SH and prevent renal failure–induced histomorphometric changes in bone with minimal calcemic and phosphatemic activity. However, information about its efficacy on restoration of bone structural strength is lacking. In this study, we explored the effects of paricalcitol treatment on bone structure and strength in a model of advanced renal disease.

Materials and Methods: Forty-five 8-week-old rats were randomly assigned to either surgical 5/6 nephrectomy (NTX) or Sham-operation. After a 15-week postoperative disease progression period, the NTX rats were further allocated to uremic control (NTX) and treatment (NTX + paricalcitol) groups, the latter of which received paricalcitol for the subsequent 12 weeks. After 27 weeks, the animals were killed, plasma samples were collected, and both femora were excised for comprehensive analysis of the femoral neck and midshaft (pQCT and biomechanical testing).

Results: High mortality that exceeded 30% was observed in both NTX groups. NTX induced over a 13-fold increase in plasma PTH, whereas this increase was only 5-fold after paricalcitol treatment. At the femoral neck, NTX was associated with an 8.1% decrease (p < 0.05) in vBMD and a 16% decrease in breaking load (p < 0.05) compared with the Sham group, whereas paricalcitol treatment completely prevented these changes. At the femoral midshaft, the NTX resulted in a 6.6% decrease in cortical BMD (p < 0.01 versus Sham), and this change was also prevented by paricalcitol.

Conclusions: Paricalcitol administration prevented renal insufficiency-associated decreases in BMD in the femoral neck and the femoral midshaft and restored bone strength in the femoral neck. Therefore, paricalcitol can efficiently ameliorate renal insufficiency-induced loss of bone mineral and mechanical competence of bone.
VEGF Scaffolds Enhance Angiogenesis and Bone Regeneration in Irradiated Osseous Defects
Authors: Kaigler Darnell , Wang Zhuo , Horger Kim , Mooney David J , Krebsbach Paul H
Published: May 2006

Bone regeneration is challenging in sites where the blood supply has been compromised by radiation. We examined the potential of a growth factor (VEGF) delivery system to enhance angiogenesis and bone formation in irradiated calvarial defects. VEGF-releasing polymers significantly increased blood vessel density and vascular perfusion in irradiated defects and increased bone formation relative to control conditions.

Introduction: Radiation therapy causes damage to tissues and inhibits its regenerative capacity. Tissue injury from radiation is in large part caused by a compromised vascular supply and reduced perfusion of tissues. The aim of this study was to determine if delivery of vascular endothelial growth factor (VEGF) from a biodegradable PLGA (copolymer of d,l-lactide and glycolide) scaffold could enhance neovascularization and bone regeneration in irradiated osseous defects.

Materials and Methods: An isolated area of the calvarium of Fisher rats was irradiated (12 Gy) 2 weeks preoperatively, and two 3.5-mm osseous defects were created in this area, followed by the placement of PLGA scaffolds or VEGF scaffolds (PLGA scaffolds with incorporated VEGF) into the defects. Laser Doppler perfusion imaging was performed to measure perfusion of these areas at 1, 2, and 6 weeks. Implants were retrieved at 2, 6, and 12 weeks, and histologic and μCT analyses were performed to determine neovascularization and bone regeneration.

Results: Histological analyses revealed statistically significant increases in blood vessel formation (>2-fold) and function (30%) within the VEGF scaffolds compared with PLGA scaffolds. Additionally, evaluation of bone regeneration through bone histomorphometric and μCT analyses revealed significantly greater bone coverage (26.36 ± 6.91% versus 7.05 ± 2.09% [SD]) and increased BMD (130.80 ± 58.05 versus 71.28 ± 42.94 mg/cm3) in VEGF scaffolds compared with PLGA scaffolds.

Conclusions: Our findings show that VEGF scaffolds have the ability to enhance neovascularization and bone regeneration in irradiated osseous defects, outlining a novel approach for engineering tissues in hypovascular environments.
Ubiquitin Ligase Cbl-b Downregulates Bone Formation Through Suppression of IGF-I Signaling in Osteoblasts During Denervation
Authors: Suzue Naoto , Nikawa Takeshi , Onishi Yuko , Yamada Chiharu , Hirasaka Katsuya , Ogawa Takayuki , Furochi Harumi , Kosaka Hirofumi , Ishidoh Kazumi , Gu Hua , Takeda Shin'ichi , Ishimaru Naozumi , Hayashi Yoshio , Yamamoto Hironori , Kishi Kyoichi , Yasui Natsuo
Published: May 2006

Unloading can prevent bone formation by osteoblasts. To study this mechanism, we focused on a ubiquitin ligase, Cbl-b, which was highly expressed in osteoblastic cells during denervation. Our results suggest that Cbl-b may mediate denervation-induced osteopenia by inhibiting IGF-I signaling in osteoblasts.

Introduction: Unloading, such as denervation (sciatic neurectomy) and spaceflight, suppresses bone formation by osteoblasts, leading to osteopenia. The resistance of osteoblasts to growth factors contributes to such unloading-mediated osteopenia. However, a detailed mechanism of this resistance is unknown. We first found that a RING-type ubiquitin ligase, Cbl-b, was highly expressed in osteoblastic cells after sciatic neurectomy in mice. In this study, we reasoned that Cbl-b played an important role in the resistance of osteoblasts to IGF-I.

Materials and Methods: Cbl-b–deficient (Cbl-b–/–) or wildtype (Cbl-b+/+) mice were subjected to sciatic neurectomy. Bone formation in these mice was assessed by calcein labeling and histomorphometric analyses. We examined IGF-I signaling molecules in femora of these mice by Western blot and immunohistochemical analyses. We also examined the mitogenic response of Cbl-b–overexpressing or –deficient osteoblastic cells to various growth factors.

Results: In Cbl-b+/+ mice, denervation decreased femur mass and bone formation, whereas it increased the expression of Cbl-b protein in osteoprogenitor cells and in osteocalcin-positive cells (osteoblastic cells) in hindlimb bone. In contrast, in Cbl-b−/− mice, bone mass and bone formation were sustained during denervation. Denervation inhibited the mitogenic response of osteoprogenitor cells most significantly to IGF-I. Therefore, we focused on Cbl-b–mediated modification of IGF-I signaling. Denervation decreased the amounts of insulin receptor substrate-1 (IRS-1), phosphatidly inositol 3-phosphate kinase (PI3K), and Akt-1 proteins in femora of Cbl-b+/+ mice, whereas the amounts of these IGF-I signaling molecules in femora of Cbl-b–/– mice were constant after denervation. On a cellular level, primary osteoblastic cells from Cbl-b–/– mice were more stimulated to proliferate by IGF-I treatment compared with those from Cbl-b+/+ mice. Furthermore, overexpression of Cbl-b increased ubiquitination and degradation of IRS-1 in primary Cbl-b–/– osteoblastic cells, leading to their impaired mitogenic response to IGF-I.

Conclusions: These results suggest that Cbl-b induces resistance of osteoblasts to IGF-I during denervation by increasing IRS-1 degradation and that Cbl-b–mediated modification of IGF-I signaling may contribute to decreased bone formation during denervation.
Ghrelin and Bone: Is There an Association in Older Adults?: The Rancho Bernardo Study
Authors: Weiss Lauren A , Langenberg Claudia , Barrett-Connor Elizabeth
Published: May 2006

Laboratory studies suggest that ghrelin is involved in bone metabolism, but studies of ghrelin and bone in humans are limited. We studied sex-specific associations of ghrelin with BMD, NTX, and bone loss. Ghrelin was not associated with BMD or bone loss in either sex. There was a significant inverse association with NTX in men but not in women.

Introduction: Ghrelin is a gastric hormone recently shown to be associated with bone metabolism in animal and in vitro studies. Studies in humans are limited. We investigated the association of ghrelin with BMD, the bone resorption marker N-telopeptide (NTX), and bone loss in older men and women.

Materials and Methods: Participants were 977 community-dwelling men and non–estrogen-using postmenopausal women, 50–91 years of age. Plasma ghrelin was measured by radioimmunoassay from blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA. Axial BMD measurements were repeated an average of 4 years later in 544 participants. Bone turnover was assessed by NTX in urine obtained at the same time as the initial BMD. Multiple regression analyses were used to test sex-specific associations of ghrelin with BMD, NTX, and bone loss in both sexes.

Results: No significant ghrelin–BMD or ghrelin–bone loss associations were observed in either sex, after adjusting for age and body mass index (BMI). Ghrelin was inversely associated with NTX in men and positively associated with NTX in women, independent of age. After adjusting for both age and BMI, this association reached statistical significance in men and was weakened in women.

Conclusions: Ghrelin may be associated with bone turnover, but there is no evidence for an association with BMD or short-term change in BMD in older adults.
Beyond Lucian Freud: Exploring body representations in children's culture
Authors: Vidiella Judit , Hernndez Fernando
Published: May 2006

In this article we show how theory of Visual Culture Studies can be put into practice in schools. We report on a collaboration between the Department of Art Education in the Fine Art Faculty of the University of Barcelona and an urban primary school. It took the form of Inquiry-based
Project Work focussing on alternative ways of understanding and implementing Visual Art Education. Specifically, we investigated a traditional Art History topic (the life and work of the artist Lucian Freud) and explored this from the perspective of Visual Culture Studies. Three aspects of
this work are presented and discussed: (a) how art historical representations fix discourse about the body in everyday situations; (b) how Lucian Freud represents people's experience of their bodies and how this affects them; and (c) how pupils experience their bodies given the way the body
is represented in media culture and everyday life.
Design for learning through the arts
Authors: Sahasrabudhe Prabha
Published: May 2006

In 1999 the Director-General of UNESCO issued an international appeal for the promotion of arts education and creativity at school. Since then UNESCO has been quite remarkable in its World-wide initiatives on behalf of art education. This article welcomes UNESCO's advocacy effort and
invites InSEA and other arts education professional groups to take notice of this activity and enjoin this worldwide dialogue as full and critical partners. This paper suggests a beginning agenda for this dialogue in two parts: a brief commentary on issues that are central to this much needed
debate, namely - arts-in-education, interdisciplinarity and school curricula, art and cognition, learning in the arts and transfer of learning to other subjects; and a model that identifies the critical curricular influences that need to be taken into account when arts are introduced into
schools as a way of knowing and as a distinctive way of learning.
Capturing the attention of readers? Stylistic and psychological perspectives on the use and effect of text fragmentation in narratives
Authors: Emmott Catherine , Sanford Anthony J , Morrow Lorna I
Published: May 2006

This article brings together researchers from Stylistics and Psychology to study whether text fragmentation, which appears often to be used by writers as a foregrounding device
(Mukařovský 1964), is able to capture the attention of readers of narratives. We examine two types of text fragmentation: sentence fragments and mini-paragraphs. Firstly, we study the stylistic functions of fragmentation, including its cumulative use at plot crucial moments and its use for local rhetorical purposes. We then turn to psychological research on depth of processing
(e.g. Sanford and Sturt 2002) and introduce a new method of testing, the text change detection method (Sturt at al. 2004). We report an experiment using this method to examine whether text fragments and very short sentences can increase the amount of detail that readers notice in a text, and then discuss the results in relation to potential applications. The work provides both a case study of the empirical analysis of foregrounding devices, and also, more generally, a case study of inter-disciplinary research across the Humanities and Social Sciences.
Induction of labour at the start of the new millennium
Authors: MacKenzie I Z
Published: May 2006

Around 20% of all deliveries are preceded by labour induction, a proportion that has not varied dramatically over recent years. Fetal death was the only indication for labour induction centuries ago, while this is now a very rare indication, with prolonged pregnancy and maternal hypertensive disorders being the major indications for the last 50–60 years. Techniques for inducing labour have also changed from dietary delicacies and verbal threats giving way to physical stimulation mainly achieved by cervical stretching and amniotomy and more recently to sophisticated pharmacological manipulation using oxytocin and prostaglandins, based on our expanding knowledge of the physiological processes involved in spontaneous parturition. Relaxin, antiprogestins, nitric oxide as well as complementary medicines have also been explored in recent years. Successful induction is, however, still not guaranteed and there has been increasing emphasis during the past decade on exploring strategies for identifying the probability of success. Measurement of fetal fibronectin in cervical mucus, maternal serum nitrite/nitrate concentrations, ultrasound delineation of cervical form and electrical impedance measurements across the cervix are all being investigated. Safety, success, and patient satisfaction continue to be the major objectives with economic evaluations now becoming a significant factor in the search for the ideal induction method.
Chromatin remodeling in somatic cells injected into mature pig oocytes
Authors: Bui Hong-Thuy , Van Thuan Nguyen , Wakayama Teruhiko , Miyano Takashi
Published: May 2006

We examined the involvement of histone H3 modifications in the chromosome condensation and decondensation of somatic cell nuclei injected into mature pig oocytes. Nuclei of pig granulosa cells were transferred into in vitro matured intact pig oocytes, and histone H3 phosphorylation, acetylation, and methylation were examined by immunostaining with specific antibodies in relation to changes in chromosome morphology. In the condensed chromosomes of pig oocytes at metaphase II, histone H3 was phosphorylated at serine 10 (H3–S10) and serine 28 (H3–S28), and methylated at lysine 9 (H3–K9), but was not acetylated at lysine 9, 14 and 18 (H3–K9, H3–K14 and H3–K18). During the first 2 h after nuclear transfer, a series of events were observed in the somatic nuclei: nuclear membrane disassembly; chromosome condensation to form a metaphase-like configuration; an increase in histone H3 phosphorylation levels (H3–S10 and H3–S28). Next, pig oocytes injected with nuclei of somatic cells were electroactivated and the chromosome morphology of oocytes and somatic cells was examined along with histone modifications. Generally, chromosomes of the somatic cells showed a similar progression of cell cycle stage to that of oocytes, through anaphase II- and telophase II-like stages then formed pronucleus-like structures, although the morphology of the spindles differed from that of oocyte spindles. The chromosomes of somatic cells also showed changes in histone H3 dephosphorylation and reacetylation, similar to oocytes. In contrast, histone H3 methylation (H3–K9) of somatic cell nuclei did not show any significant change after injection and electroactivation of the oocytes. These results suggest that nuclear remodeling including histone H3 phosphorylation and acetylation of injected somatic nuclei took place in the oocytes under regulation by the oocyte cytoplasm.
The importance of aneuploidy screening in reciprocal translocation carriers
Authors: Pujol Aïda , Benet Jordi , Staessen Catherine , Van Assche Elvire , Campillo Mercedes , Egozcue Josep , Navarro Joaquima
Published: May 2006

The purpose of this study is to investigate the aneuploidy rate and the mosaicism of chromosomes not involved in reciprocal translocations. Aneuploidy screening (AS) (13, 16, 18, 21 and 22) was performed as a re-analysis on fixed blastomeres from 126 embryos already analysed in preimplantation genetic diagnosis (PGD) cycles of eight female and five male reciprocal translocation carriers who had not achieved a pregnancy. A successful diagnosis for AS was achieved in 91.3% of embryos; 30.9% were euploid and 60.3% were aneuploid for the five chromosomes analysed. Of the embryos, 8.7% were euploid for AS and normal-balanced for the translocation and 22.2% were euploid for AS but unbalanced for the translocation; 8% of the embryos were aneuploid for AS but normal-balanced for the translocation and 52.4% were aneuploid for AS and also unbalanced for the translocation. At least 58.7% of the embryos were mosaic regarding mosaicism for the chromosomes involved and not involved in the translocations. Six of the 16 embryos transferred in the PGD cycles were aneuploid for the AS study; four of them were also mosaics. AS should be performed in reciprocal translocation carriers after segregation analysis in PGD.
Testosterone antagonist (flutamide) blocks ovulation and preovulatory surges of progesterone, luteinizing hormone and oestradiol in laying hens
Authors: Rangel P L , Sharp P J , Gutierrez C G
Published: May 2006

The preovulatory release of luteinizing hormone (LH) in the domestic hen occurs after the initiation of a preovulatory surge of testosterone. The objective of this study was to determine whether this testosterone surge has functional significance in the endocrine control of ovulation. Groups of laying hens (n=10–22) were treated with the androgen receptor antagonist, flutamide, at 8 h intervals for 24 h at doses of 0, 31.25, 62.5, 125 and 250 mg. All doses reduced egg laying (P < 0.001), with the highest dose being the most effective. In a second study, laying hens (n=9) were treated with 250 mg flutamide at 8 h intervals for 24 h with a control group being given placebo (n=10). Blood samples were taken for hormone measurements at 2 h intervals for 18 h starting 4 h before the onset of darkness. The percentage of hens laying per day did not differ between groups before treatment (control, 88% vs flutamide, 86%). Ovulation was blocked in all hens treated with flutamide within 2 days while the control hens continued to lay at the pretreatment rate (80%). Preovulatory surges of plasma testosterone, progesterone, oestradiol and LH were observed in control hens but with the exception of testosterone, flutamide treatment blocked the progesterone, oestradiol and LH surges. LH concentrations declined progressively with time in the flutamide-treated hens. It is concluded that inhibition of testosterone action blocks egg laying and the preovulatory surges of progesterone, luteinizing hormone and oestradiol demonstrating a key role for the preovulatory release of testosterone in the endocrine control of ovulation in the domestic hen.
Production of horse foals via direct injection of roscovitine-treated donor cells and activation by injection of sperm extract
Authors: Hinrichs K , Choi Y H , Love C C , Chung Y G , Varner D D
Published: May 2006

We evaluated the effects of different donor cell treatments and activation methods on production of blastocysts after equine nuclear transfer. Nuclear transfer was performed by direct injection of donor cells, using a piezo drill, and standard activation was by injection of sperm factor followed by culture with 6-dimethylaminopurine. There was no difference in blastocyst development between embryos produced with roscovitine-treated or confluent donor cells (3.6% for either treatment). Addition of injection of roscovitine or culture with cycloheximide at the time of activation did not affect blastocyst development. Overall, transfer of eight blastocysts produced using roscovitine-treated donor cells and our standard activation protocol yielded three pregnancies, of which two (25% of transferred embryos) resulted in delivery of viable foals. Flow cytometric evaluation showed that roscovitine treatment significantly increased the proportion of cells classified as small, in comparison to growth to confluence or serum deprivation, but did not significantly affect the proportion of cells in G0/G1 (2N DNA content). Transfer of one blastocyst produced using roscovitine-treated donor cells, with addition of roscovitine injection at activation, yielded one pregnancy which was lost before 114 days’ gestation. Transfer to recipients of two blastocysts produced using confluent donor cells with addition of cycloheximide at activation gave no resulting pregnancies. We conclude that roscovitine treatment of donor cells yields equivalent blastocyst production after nuclear transfer to that for confluent donor cells, and that direct injection of roscovitine-treated donor cells, followed by activation using sperm extract, is compatible with efficient production of viable cloned foals.
Performance of Endangered Bonytails Fed Four Commercial Diets
Authors: Henne James P , Romero Matthew M , Martinez Teresa V , Fillmore Brian M , Gannam Ann L , Carmichael Gary J
Published: May 2006

The bonytail Gila elegans is a critically endangered cyprinid that is endemic to the southwestern United States, where it is cultured in ponds and water reuse systems as part of recovery efforts. Unlike in extensive outdoor pond culture, where natural food productivity plays a primary nutritional role, manufactured feed must provide complete nourishment for fish reared indoors in recirculating systems. The objective of this study was to determine the effects of diet on the growth and survival of juvenile bonytails fed four commercially available feeds over a 120-d period. The four treatment diets were identified as a catfish diet, a trout diet, a high-protein shrimp diet, and a low-protein shrimp diet. Significant (P < 0.05) differences in growth among treatments were observed on sampling day 102. By day 120, the average weight of fish fed the high-protein shrimp diet (36.3 g) was significantly higher than the weights of fish fed the catfish (26.6 g), trout (24.7 g), and low-protein shrimp diets (24.2 g). The specific growth rates measured on days 102 and 120 were significantly greater for bonytails fed the high-protein shrimp diet than for fish fed the other treatments. The feed conversion ratio of fish fed the high-protein shrimp diet was significantly better than those of fish fed the trout and low-protein shrimp diets, while the protein efficiency ratio and apparent net protein retention were generally higher in the high- and low-protein shrimp diet treatment groups than in the other two treatment groups. Overall survival was high (93.5%) and did not differ significantly among treatment groups (P ≥ 0.05) through 120 d.
Evaluation of Six Feeding Regimens for Survival and Growth of Shortnose Sturgeon Fry
Authors: Ware Kent M , Henne James P , Hickson Brian H , Charlesworth Kevin
Published: May 2006

The shortnose sturgeon Acipenser brevirostrum is a federally listed endangered fish species cultured for recovery efforts. Since high mortality and labor costs are associated with first-feeding sturgeon culture, particularly during the period of dietary conversion from live to formulated feed, we investigated the effects of six feeding regimens on the survival and growth of cultured shortnose sturgeon fry. During the 30-d trial, five replicate groups (100 fish/replicate) of first-feeding shortnose sturgeon were fed according to six regimens: (1) live feed (live nauplii of brine shrimp Artemia spp.); (2) formulated (commercially formulated salmonid starter diet); (3) alternate (alternate feedings of the live and formulated feed); (4) transition (slow transition from the live to the formulated feed); (5) automatic (cofeeding the live and formulated feeds with the use of an automatic feeder); and (6) starvation (no feeding). Significantly greater survival rates were observed in the transition (97.4%), automatic (96.0%), alternate (93.8%), and live feed regimens (92.6%) than in the formulated (71.8%) and starvation regimens (31.6%). Length and weight of fish in the alternate (52.4 mm and 0.62 g), automatic (52.3 mm and 0.63 g), transition (46.9 mm and 0.48 g), and live feed regimens (46.4 mm and 0.43 g) were significantly greater than the length and weight of fish in the formulated (31.4 mm and 0.18 g) and starvation regimens (20.6 mm and 0.04 g). Fish weights in the alternate and automatic regimens were significantly greater than those in the live feed regimen. Based on the results of this study, we recommend the automatic regimen for first-feeding shortnose sturgeon culture. This feeding regimen produced heavier fish than the live feed regimen, appeared to reduce labor costs compared with the other feeding regimens, and alleviated possible complications associated with diet conversion.
Efficacy of 17-α-Methyltestosterone for Expression of Male Secondary Sexual Characteristics in the Green Swordtail
Authors: Yanong Roy P E , Hill Jeffrey E , Daniels Chris J , Watson Craig A
Published: May 2006

The green swordtail Xiphophorus hellerii is a commercially important ornamental species. Because phenotypic males (specifically, fish with the sword extension of the caudal fin) are more valuable economically than fish lacking the sword, masculinization by means of 17-α-methyltestosterone (MT) was tested. Populations of market-size experimental fish, a mix of females and late-maturing males (i.e., lacking male secondary characteristics) were fed MT-treated feed (60 mg MT/kg feed) at a rate of 30 or 50 g of MT-treated feed per kilogram of fish biomass (3% or 5% body weight [BW]) for 28 consecutive days to cause development of male secondary sexual characteristics, specifically the growth of the sword extension. Use of MT feed at 3% or 5% BW for 28 d resulted in 100% masculinization, whereas 0% masculinization occurred in green swordtails fed control feed. No regression of swords was seen 28 d after the last day of experimental feed treatment. There were no significant differences in mortality among treatments. The use of MT-treated feeds can increase the production of higher-value phenotypic male green swordtails and enhance profitability for aquaculturists.
Evaluation of a Sodium Hydroxymethanesulfonate Product for Reducing Total Ammonia Nitrogen in a Small-Scale Rotifer Batch Culture System
Authors: Riche Marty , Pfeiffer Timothy J , Garcia Javier
Published: May 2006

The total ammonia nitrogen (TAN) produced as metabolic waste in rotifer batch culture systems can reach toxic concentrations as un-ionized ammonia (UIA). Sodium hydroxymethanesulfonate has been used to neutralize TAN in hauling and shipping containers for fish, crustaceans, and mollusks. The objective of this study was to determine the efficacy of a sodium hydroxymethanesulfonate product to neutralize ammonia in a rotifer batch culture system. Rotifers Brachionus rotundiformis were stocked at an initial concentration of 80 individuals/mL and were batch-cultured without water exchange for 7 d. We evaluated response variables that included TAN concentration, rotifer production, egg count, and egg : female ratio. Mean maximum TAN was 3.3 mg/L (0.08 mg UIA per liter of water) and 9.5 mg/L (0.84 mg/L UIA) for treated and control groups, respectively. Significant differences were detected in TAN, rotifer density, egg count, and egg : female ratio beginning on day 3 (P < 0.05). Beginning on day 2, mean rotifer density declined exponentially in the control group (y = 293.4 · e  −0.249x; R  2 = 0.98) but remained constant in the treated group. Correlation coefficients indicated that TAN explained 72% of the population decrease. We conclude that the use of a sodium hydroxymethanesulfonate product as an ammonia neutralizer is effective in decreasing TAN and UIA in a small-scale rotifer batch culture system.
Production of Recombinant Adeno‐Associated Viral Vectors and Use for In Vitro and In Vivo Administration
Authors: Choi Vivian W. , Asokan Aravind , Haberman Rebecca A. , McCown Thomas J. , Samulski Richard Jude
Published: May 2006

Adeno‐associated virus is a nonpathogenic human virus that has been developed into a gene‐delivery vector due to its high efficiency of infection for many different cell types and its ability to persist and lead to long‐term gene expression. This unit describes efficient methods to generate high‐titer, research‐grade, adenovirus‐free recombinant single‐stranded and self‐complementary adeno‐associated virus in various serotypes, along with methods to quantify the viral vectors. Two detailed methods are provided for viral vector injection into rat brain and for histological detection of transgene expression, including lacZ and GFP.
Flow Rate Calibration for Absolute Cell Counting Rationale and Design
Authors: Walker Clare , Barnett David
Published: May 2006

There is a need for absolute leukocyte enumeration in the clinical setting, and accurate, reliable (and affordable) technology to determine absolute leukocyte counts has been developed. Such technology includes single platform and dual platform approaches. Derivations of these counts commonly incorporate the addition of a known number of latex microsphere beads to a blood sample, although it has been suggested that the addition of beads to a sample may only be required to act as an internal quality control procedure for assessing the pipetting error. This unit provides the technical details for undertaking flow rate calibration that obviates the need to add reference beads to each sample. It is envisaged that this report will provide the basis for subsequent clinical evaluations of this novel approach.
Thermochemistry of Organic and Heteroorganic Species. Part 19. Structural Aspects and Thermochemical Approach to Isomerization and Fragmentation of Negative Ions: Skeletal Rearrangements, Molecular Ion and Artifacts
Authors: Ponomarev Dmitry , Takhistov Viatcheslav
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Examination of granule layer cell count, cell density, and single‐pulse brdu incorporation in rat organotypic hippocampal slice cultures with respect to culture medium, septotemporal position, and time in vitro
Authors: Sadgrove Matthew P. , Laskowski Alexandra , Gray William P.
Published: May 2006

Adult neurogenesis in the dentate gyrus is assuming an increasingly important role in supporting hippocampal‐dependent learning and the modulation of mood and anxiety. Moreover, injury to the developing postnatal dentate gyrus has profound effects on neurogenesis and hippocampal learning throughout life. Organotypic hippocampal slice cultures represent an attractive model for studying neurogenesis both in the early postnatal and adult hippocampus, as they retain much of their anatomical and functional circuitry in vitro. Ongoing neurogenesis has been recently demonstrated in organotypic hippocampal slice cultures. However, cell proliferation, one of the critical components of neurogenesis, has yet to be characterized in this culture system. We examined single‐pulse S‐phase bromo‐deoxyuridine (BrdU) labeling in the dentate granule layer with respect to the septotemporal position of origin of the slice culture, the medium the cultures were grown in, and the time the cultures were maintained in vitro up to 14 days, when they are believed to have matured to a near adult state. Using single 10‐μm sections through a culture as our reference volume, we report significant effects of septotemporal position on the number of granule layer cells and the number of cells in S‐phase, as estimated by short‐survival (2 hours) BrdU studies. We report a declining rate of BrdU incorporation, evidence of significant structural changes within the granule cell layer, and differences in cell death between culture media over the first 14 days in vitro. We report caution with the use of BrdU cell density and changes in cell number to indirectly estimate proliferation. J. Comp. Neurol. 497:397–415, 2006. © 2006 Wiley‐Liss, Inc.
DISC1 immunoreactivity at the light and ultrastructural level in the human neocortex
Authors: Kirkpatrick Brian , Xu Leyan , Cascella Nicola , Ozeki Yuji , Sawa Akira , Roberts Rosalinda C.
Published: May 2006

Disrupted‐In‐Schizophrenia 1 (DISC1) is one of two genes that straddle the chromosome 1 breakpoint of a translocation associated with an increased risk of schizophrenia. DISC1 has been identified in the brain of various mammalian species, but no previous immunocytochemical studies have been conducted in human neocortex. We examined DISC1 immunoreactivity in frontal and parietal cortex (BA 4, 9, 39, and 46) in normal human brain. At the light microscopic level, immunolabeling was prominent in the neuropil, in multiple populations of cells, and in the white matter. At the ultrastructural level, staining was prominent in structures associated with synaptic function. Immunolabeled axon terminals comprised 8% of all terminals and formed both asymmetric and symmetric synapses. Labeled axon terminals formed synapses with labeled spines and dendrites; in some, only the postsynaptic density (PSD) of the postsynaptic structure was labeled. The most common configuration, however, was an unlabeled axon terminal forming an asymmetric synapse with a spine that had immunoreactivity deposited on the PSD and throughout the spine. The presence of DISC1 in multiple types of synapses suggests the involvement of DISC1 in corticocortical as well as thalamocortical connections. Staining was also present in ribosomes, parts of the chromatin, in dendritic shafts, and on some microtubules. Labeling was absent from the Golgi apparatus and multivesicular bodies, which are associated with protein excretion. These anatomical localization data suggest that DISC1 participates in synaptic activity and microtubule function, and are consistent with the limited data on its adult function. J. Comp. Neurol. 497:436–450, 2006. © 2006 Wiley‐Liss, Inc.
Embryogenesis of the serotonergic system in the earthworm Eisenia fetida (Annelida, Oligochaeta): Immunohistochemical and biochemical studies
Authors: Koza Anna , Wilhelm Márta , Hiripi László , Elekes Károly , Csoknya Mária
Published: May 2006

Organization of the serotonergic system and changes of the serotonin (5‐HT) content were studied during the embryogenesis of the earthworm Eisenia fetida, using immunocytochemistry and HPLC. A gradual emergence of 5‐HT immunoreactive (IR) cells and their axon projections in the several ganglia of the central (CNS) and peripheral nervous system are described in the context of a staged time‐scale of development. The first 5‐HT‐IR neurons appear in the subesophageal ganglion at an early embryonic stage (E2), followed by neurons in some rostrally located ventral ganglia. In the cerebral ganglion, 5‐HT‐IR cells can be detected only from stage E5. The number of labeled cells in each ganglion of the embryo increases until hatching, when it is still considerably lower than that observed in adults. This shows that the development of the 5‐HTergic system is far from complete by the end of embryogenesis. Organization of 5‐HT‐IR innervation of the body wall starts by stages E3 to E4. In the stomatogastric nervous system the first 5‐HT‐IR fibers can be detected by stage E5. By stage E9 5‐HT immunopositive neurons can be observed in both the stomatogastric ganglia and the enteric plexus. Both 5‐HT levels and the numbers of the labeled cells show a significant increase before hatching, which indicate a functional maturation of the 5‐HTergic system. Based on the early appearance of 5‐HT, we suppose that it may play a regulatory role in both the gangliogenesis and the maturation of peripheral functions necessary during postembryonic life. J. Comp. Neurol. 497:451–467, 2006. © 2006 Wiley‐Liss, Inc.