bluuebunny/crossref_metadata_2025 huggingface dataset:
In vitro effect of adenovirus‐mediated human Gamma Interferon gene transfer into human mesenchymal stem cells for chronic myelogenous leukemia
Authors: Li XiaoQing , Lu Yue , Huang WenLin , Xu HaiPeng , Chen XiaoQin , Geng QiRong , Fan HuiJie , Tan YinDuo , Xue Gang , Jiang XiangLi
Published: May 2006

For developing gene therapy for chronic myelogenous leukemia (CML), we evaluated the feasibility of using autologous bone marrow stromal cells (BMSCs) of one CML patient as a target cell population and studied the efficiency of recombinant adenovirus‐mediated human Gamma Interferon (hIFN‐γ) gene transfer into BMSCs. BMSCs can be readily obtained, expanded, and successfully transduced with adenoviral vectors in vitro. We studied the in vitro expression of hIFN‐γ in human BMSCs following transduction with Ad/hIFN‐γ. On transduction of BMSCs at a MOI of 50, the expression and secretion of hIFN‐γ were achieved as high as 5492 ± 660∼50647 ± 4049 ng/106 cells per 24 h over the course of 3 weeks. We further studied the effects of hIFN‐γ produced by transduced BMSCs on the proliferation of the human leukemia cell line K562 cells in vitro, proliferation of K562 cells was markedly inhibited in the experimental groups as compared with the other two control groups after 5 days of coculture. We also found that the percentage of K562 cells in the G1 phase of cell cycle can be increased by treatment of hIFN‐γ produced by Ad/hIFN‐γ transduced BMSCs, but the percentage of K562 cells in the S phase of cell cycle can be decreased in the same time. Apoptosis rate of K562 cells in the experimental groups was 30.8 ± 8.5%, as compared with the other two control groups (5.6 ± 1.3% and 5.5 ± 0.8%, respectively) (p < 0.01). Our results indicate that hIFN‐γ gene engineered BMSCs of CML donors could be successfully established and that local production of hIFN‐γ is sufficiently to inhibit the proliferation of K562 cells and induce apoptosis of K562 cells in vitro, suggesting an important potential use in the clinical gene therapy of CML. Copyright © 2006 John Wiley & Sons, Ltd.
Three‐dimensional structure of the zona pellucida at ovulation
Authors: Familiari Giuseppe , Relucenti Michela , Heyn Rosemarie , Micara Giulietta , Correr Silvia
Published: May 2006

The mammalian zona pellucida (ZP) is an extracellular matrix surrounding oocytes and early embryos, which is critical for normal fertilization and preimplantation development. It is made up of three/four glycoproteins arranged in a delicate filamentous matrix. Scanning electron microscopy (SEM) studies have shown that ZP has a porous, net‐like structure and/or nearly smooth and compact aspect. In this study, the fine 3‐D structure of the human and mouse ZP is reviewed with the aim to integrate ultrastructural and molecular data, considering that the mouse is still used as a good model for human fertilization. By conventional SEM observations, numerous evidences support that the spongy ZP appearance well correlates with mature oocytes. When observed through more sophisticated techniques at high resolution SEM, ZP showed a delicate meshwork of thin interconnected filaments, in a regular alternating pattern of wide and tight meshes. In mature oocytes, the wide meshes correspond to “pores” of the “spongy” ZP, whereas the tight meshes correspond to the compact parts of the ZP surrounding the pores. In conclusion, the traditional “spongy” or “compact” appearance of the ZP at conventional SEM appears to be only the consequence of a prevalence of different arrangements of microfilament networks, according to the maturation stage of the oocyte, and in agreement with the modern supramolecular model of the ZP at the basis of egg–sperm recognition. Despite great differences in molecular characterization of ZP glycoproteins between human and mouse ZP, there are no differences in the 3‐D organization of glycoproteic microfilaments in these species. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Immune system involvement in the regulation of ovarian function and augmentation of cancer
Authors: Bukovsky Antonin
Published: May 2006

Increasing evidence indicates a role for the immune system and mesenchymal–epithelial interactions in the regulation of ovarian function. Cytokines produced by mesenchymal cells can stimulate development and regression of ovarian structures. We report here that mesenchymal cells releasing surface molecules among epithelial cells—namely vascular pericytes and monocyte‐derived cells (MDC)—and intraepithelial T lymphocytes are associated with oogenesis and formation of new primary follicles in both fetal and adult human ovaries. These activated mesenchymal cells interact with the ovarian surface epithelium, which appears to be a source of secondary germ cells and granulosa cells. Activated pericytes and MDC are also associated with stimulation of thecal development during selection of growing secondary follicles from the cohort of primary follicles. However, survival of the dominant follicle during mid‐follicular phase selection is associated with a lack of activity of mesenchymal cells and retardation of thecal development, since immature granulosa cells lacking aromatase are unable to resist high levels of thecal androgens. Once the selected follicle matures (late follicular phase), it shows enhanced activity of thecal mesenchymal cells and advanced thecal development. Corpus luteum (CL) development is accompanied by a high activity of vascular pericytes and MDC. In mature CL and CL of pregnancy, luteal MDC and pericytes show a stable (inactive) state. Regression of the CL is associated with regression of pericytes, transformation of MDC into dendritic cells, infiltration by T lymphocytes, and binding of immunoglobulin G to the luteal cells. The immunoglobulin M (IgM) binds to young but not mature luteal cells. In the CL of pregnancy, IgM binds to luteal vessels, but not to luteal cells. Regressing CL shows IgM binding to both luteal cells and vessels. In ovarian cancers, highly activated MDC and sometimes activated pericytes (poorly differentiated carcinomas) are present. IgM binding is similar to that seen in the CL of pregnancy. These data indicate that vascular pericytes, MDC, T cells, and immunoglobulins may play an important role in the regulation of ovarian physiology and contribute to the augmentation of ovarian cancer growth. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Presence and significance of temperature gradients among different ovarian tissues
Authors: Hunter Ronald Henry Fraser , Einer‐Jensen Niels , Greve Torben
Published: May 2006

After recalling male gonadal physiology in respect of tissue temperatures within the scrotal sac, and raising questions concerning abdominal testes, attention turned to mature Graafian follicles and ovarian stroma. Temperature gradients between such tissues were summarized for human, rabbit, pig, and cow, and generally fell in the range of 1.3–1.7°C: follicles were always cooler than stroma. Measurements were made principally by means of a thermo‐sensing camera at midventral laparotomy, but also using microelectrodes or thermistor probes sited in the follicular antrum of rabbits and pigs, respectively. When thermo‐imaged under the fimbriated extremity of the Fallopian tube, mature pig follicles and stroma could still be distinguished. Such follicles cooled slightly more rapidly during the first 10 s of a 60‐s recording interval, after which curves for the two tissues remained parallel. Arresting ovarian blood supply for 5 min had a negligible influence on the temperature differentials. Endoscopy in three models recorded mean differentials of 0.6 ± 0.1°C – 1.1 ± 0.1°C between follicles and stroma, but such follicles had not attained mature diameter. Temperature gradients were thought to be generated at least in part by endothermic reactions within mature follicles, reflecting hydration of large extracellular matrix molecules such as proteoglycans. A contribution to the cooling process from the products of leukocyte activity in the follicle wall and antrum could also be involved. Temperature gradients would be maintained locally by counter‐current heat exchange mechanisms and, in this context, the microvasculature and lymphatic flow of individual follicles were found to be appropriate. Observations on the temperature of preovulatory follicles appear relevant to procedures of in vitro maturation and in vitro fertilization. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Antisymmetric flows on planar graphs
Authors: Marshall T. H.
Published: May 2006

We prove that every oriented planar graph admits a homomorphism to the Paley tournament P271 and hence that every oriented planar graph has an antisymmetric flow number and a strong oriented chromatic number of at most 271. © 2006 Wiley Periodicals, Inc. J Graph Theory 52: 200–210, 2006
Improper choosability of graphs and maximum average degree
Authors: Havet Frédéric , Sereni Jean‐Sébastien
Published: May 2006

Improper choosability of planar graphs has been widely studied. In particular, Škrekovski investigated the smallest integer gk such that every planar graph of girth at least gk is k‐improper 2‐choosable. He proved [9] that 6 ≤ g1 ≤ 9; 5 ≤  g2 ≤ 7; 5 ≤ g3 ≤ 6; and ∀ k ≥ 4, gk = 5. In this article, we study the greatest real M(k, l) such that every graph of maximum average degree less than M(k, l) is k‐improper l‐choosable. We prove that if l ≥ 2 then $M(k, l) \geq l + {l {\rm k} \over {l+k}}$. As a corollary, we deduce that g1 ≤ 8 and g2 ≤ 6, and we obtain new results for graphs of higher genus. We also provide an upper bound for M(k, l). This implies that for any fixed l, $M(k,l) \displaystyle\mathop{\longrightarrow}_{k \rightarrow \infty}{2l}$. © 2006 Wiley Periodicals, Inc. J Graph Theory 52: 181–199, 2006
Ion‐exchange macroporous hydrophilic gel monolith with grafted polymer brushes
Authors: Savina Irina N. , Galaev Igor Yu. , Mattiasson Bo
Published: May 2006

The grafting of functional polymers to the pore surface of macroporous monolithic polyacrylamide cryogels was found to be an efficient and convenient method for the preparation of macroporous polyacrylamide gels, so‐called cryogels (pAAm cryogels), with both controlled extent of functional group incorporated and with tailored surface chemistries. Anion‐exchange polymer chains of poly(2‐(dimethylamino)ethyl methacrylate) (pDMAEMA) and poly([2‐(methacryloyloxy)ethyl]‐trimethylammonium chloride) (pMETA), and cation‐exchange polymer chains of polyacrylate have been grafted onto pAAm cryogels using potassium diperiodatocuprate as initiator. It was possible to achieve the ion‐exchange capacity up to 0.2–0.5 mmol/ml. The graft polymerization did not alter the macroporous structure of the pAAm cryogel, however the flow rate of solutes through the cryogel matrix decreased with increase in the density of polymer grafted. The sorption of low‐molecular‐weight (metal ion, dye) and high‐molecular‐weight (protein) substances on the grafted monolithic pAAm column has been studied. The results indicate that a ‘tentacle’‐type binding of protein to grafted polymer depended on the architecture of the grafted polymer layer and took place after a certain degree of grafting has been reached. The binding of proteins by tentacle‐like polymer chains allowed for increasing the binding capacity for proteins on the grafted pAAm cryogels up to 6–12 mg/ml. Copyright © 2006 John Wiley & Sons, Ltd.
Macroporous polyacrylamide monolithic gels with immobilized metal affinity ligands: the effect of porous structure and ligand coupling chemistry on protein binding
Authors: Plieva Fatima , Bober Beata , Dainiak Maria , Galaev Igor Yu. , Mattiasson Bo
Published: May 2006

Macroporous polyacrylamide gels (MPAAG) with iminodiacetic acid (IDA) functionality were prepared by (i) chemical modification of polyacrylamide gel, (ii) co‐polymerization of acrylamide with allyl glycidyl ether (AGE) and N,N′metylene‐bis(acrylamide) (MBAAm) followed by coupling IDA ligand or (iii) by copolymerization of acrylamide and MBAAm with functional monomer carrying IDA‐functionality (1‐(N,N‐bis(carboxymethyl)amino‐3‐allylglycerol). Screening for optimized conditions for the production of the MPAAG with required porous properties was performed in a 96‐well chromatographic format that allowed parallel production and analysis of the MPAAG prepared from reaction mixtures with different compositions. Scanning electron microscopy of the fabricated MPAAG revealed two different types of the porous structures: monomodal macroporous structure with large interconnected pores separated by dense non‐porous pore walls in case of plain gels or gels produced via copolymerization with AGE. The other type of the MPAAG (gel produced via co‐polymerization with functional monomer carrying IDA‐functionality) had bimodal pore structure with large interconnected pores separated by the pore walls pierced through with micropores. The effect of different modifications of MPAAG monoliths and of porous structure of the MPAAG (monomodal and bimodal porous structure) on protein binding has been evaluated. Copyright © 2006 John Wiley & Sons, Ltd.
Role of chemical structure in molecular recognition by transferrin
Authors: Takátsy Anikó , Hodrea Judit , Majdik Cornelia , Dan Irimie Florin , Kilár Ferenc
Published: May 2006

Studies of molecular recognition of chiral compounds by proteins are of importance from many points of view. The biological role of proteins in their interaction with small molecules is of fundamental interest and can be used in many different fields, for instance for in vitro analysis of optically active compounds. Studies in these areas need a detailed study of the interaction sites on the protein surface and the relationship between chemical structure and the complex formation ability of small molecules, such as drugs. The electrophoretic migration of charged compounds through a protein zone may provide information about the surface properties of the macromolecule in the interaction site. The interaction of human serum transferrin with tryptophan‐methyl‐ (TME), ethyl‐ (TEE) and butyl‐esters (TBE) has been investigated by capillary electrophoresis (CE) and model calculations. Differences in the separation of tryptophan derivatives were obtained by varying experimental parameters such as, pH, ionic strength of background electrolyte and the length of transferrin zone. Limited separation of the enantiomer pairs were observed at pH 5 and 7 with a maximum resolution at pH 6. The size of the ligands coupled to the chiral centre has importance in stereoselective recognition; however, a direct comparison of resolution different in same runs may lead to false conclusion if the experimental conditions are not comparable. With a careful evaluation of the data we obtained significant differences between the resolution of the smallest enantiomer pair compared to those of tryptophan derivatives with longer alkyl chains. Copyright © 2006 John Wiley & Sons, Ltd.
Effect of the stage of growth, wilting and inoculation in field pea (Pisum sativum L.) silages. I. Herbage composition and silage fermentation
Authors: Borreani Giorgio , Cavallarin Laura , Antoniazzi Sara , Tabacco Ernesto
Published: May 2006

The stage of growth, field wilting and inoculation with lactic acid bacteria (LAB) effects were studied by ensiling herbage of field pea (Pisum sativum L.) at four consecutive stages. Stands of semi‐leafless field pea, sown in spring, were harvested at four progressive morphological stages (end of flowering, I; beginning of pod filling, II; advanced pod filling, III; beginning of ripening, IV). For each stage of growth, the herbage was field wilted to a dry matter (DM) content of 318, 300, 348 and 360 g kg−1 for stages I, II, III and IV, respectively. The unwilted and wilted herbages were ensiled in 5‐L silos, with (I) and without (C) a LAB inoculant (Lactobacillus plantarum). High levels of ethanol, lactic acid and volatile fatty acids (VFA) were observed in all silages, facilitated by the high levels of water‐soluble carbohydrates (WSC) at ensiling (from 111 to 198 g kg−1 DM). Despite the low pH values (4.3 and 4.1 for C and I silages, respectively), all the silages showed detectable levels of butyric acid. Field peas can be successfully ensiled after a short wilting period with reduced field curing and reduce DM losses onward from advanced pod filling stage, with the aid of LAB inoculum. Copyright © 2006 Society of Chemical Industry
Effect of the stage of growth, wilting and inoculation in field pea (Pisum sativum L.) silages. II. Nitrogen fractions and amino acid compositions of herbage and silage
Authors: Cavallarin Laura , Antoniazzi Sara , Tabacco Ernesto , Borreani Giorgio
Published: May 2006

The aim of the study was to investigate the effects of stage of maturity, wilting and inoculant application on proteolysis in field pea herbage and silage in northern Italy. Semi‐leafless field peas were harvested at four progressive morphological stages (end of flowering, I; beginning of pod filling, II; advanced pod filling, III; beginning of ripening, IV). For each stage of growth, the herbage was field wilted to a dry matter (DM) content around 330 g kg−1. The unwilted and wilted herbages were ensiled with (I) and without (C) a lactic acid bacteria (LAB) inoculant. The stage of growth significantly affected all the nitrogen fraction concentrations both in herbage and in silage. Extensive proteolysis took place in silages made at early morphological stages and characterised by a high crude protein content (around 240 g kg−1 DM), as shown by the non‐protein nitrogen (NPN) value (around 700 g kg−1 total N or higher). Neither inoculum nor wilting helped to reduce the protein degradation in these silages. The level of proteolysis was reduced in silages made from the pod filling stage onwards where most of the protein was localised in the seed and a better fermentation pattern was observed. The amino acid (AA) composition of silages made at stage IV was close to that of fresh herbage, with minimal losses of nutritionally essential amino acids for ruminants. Copyright © 2006 Society of Chemical Industry
The rise and fall of a community of practice: a descriptive case study
Authors: Chua Alton Y. K.
Published: May 2006

For more than a decade, the notion of communities of practice has drawn attention from both scholars and practitioners. Its popularity has been fuelled, in part, by the realisation that knowledge is heavily social in nature. Communities of practice therefore provide an ideal context for developing, sharing and stewarding knowledge in organisations. Many knowledge management researchers present communities of practice as a compelling form of informal organisational structure capable of producing remarkable outcomes. However, eclipsed by the celebrations of numerous success stories are unpublished but nonetheless important cases in which efforts to build and sustain communities of practice have failed. This paper traces the inception, development and eventual demise of a community of practice among e‐learning instructional designers at Holden College. It also attempts to explain why the initiative, which seemed to enjoy a promising start, fizzled out completely in less than one‐and‐a‐half years. The key learning points distilled from this case can be used to inform managers who are contemplating starting communities of practice in their own organisations. Copyright © 2006 John Wiley & Sons, Ltd.
Knowledge management and the vision machine: Paul Virilio and the technological constitution of knowledge
Authors: Styhre Alexander
Published: May 2006

Knowledge management has become an influential discourse within the field of management studies. Even though there are several competing perspectives and views of the notion of knowledge and its use in organization, there is relatively little emphasis on the relationship between the use of technological systems and the constitution of knowledge. This paper suggests that the writing of Paul Virilio, a though‐provoking French social and cultural theorist, may serve as a source of influence in a more active engagement with understanding the relationship between technology and knowledge. Drawing on two studies of knowledge in use in organizations, one in the domain of the juridical system and the other in new drug development in pharmaceutical industry, the paper points at the importance of integrating technologies into the analysis of how knowledge is produced. Copyright © 2006 John Wiley & Sons, Ltd.
Fracture risk after the diagnosis of Parkinson's disease: Influence of concomitant dementia
Authors: Melton L. Joseph , Leibson Cynthia L. , Achenbach Sara J. , Bower James H. , Maraganore Demetrius M. , Oberg Ann L. , Rocca Walter A.
Published: May 2006

In an inception cohort of 196 Olmsted County, Minnesota, residents with Parkinson's disease (PD) first recognized in 1976 to 1995, we tested whether the increased risk of bone fractures is associated with concomitant dementia. Using the data resources of the Rochester Epidemiology Project, information about PD, dementia, other clinical risk factors for fracture and fracture events was obtained from review of complete inpatient and outpatient medical records spanning each subject's residence in the community. Compared to an equal number of age‐ and sex‐matched non‐PD referent subjects from the community, PD patients were at a 2.2‐fold increased risk of fractures generally and a 3.2‐fold greater risk of hip fractures specifically. Adjusting for age, the independent predictors of overall fracture risk in the PD subjects included female sex (hazard ratio [HR] 1.6; 95% confidence interval [CI], 1.1–2.3), dementia (HR, 1.6; 95% CI, 1.1–2.4) and chronic depression, which was associated with a reduced risk (HR, 0.4; 95% CI, 0.2–0.8). Hip fractures were predicted by dementia (HR, 2.2; 95% CI, 1.2–4.1). The increased fracture risk in patients with PD is not entirely explained by concomitant dementia, and additional study is needed to determine the relative contributions to fracture risk of falls versus bone loss in these patients. © 2006 Movement Disorder Society
MEP latency shift after implantation of deep brain stimulation systems in the subthalamic nucleus in patients with advanced Parkinson's disease
Authors: Hidding Ute , Bäumer Tobias , Siebner Hartwig Roman , Demiralay Cüneyt , Buhmann Carsten , Weyh Thomas , Moll Christian , Hamel Wolfgang , Münchau Alexander
Published: May 2006

Deep brain stimulation (DBS) into the subthalamic nucleus (STN) is a highly effective treatment for advanced Parkinson's disease (PD). The consequences of STN stimulation on intracortical and corticospinal excitability have been addressed in a few studies using transcranial magnetic stimulation (TMS). Although excitability measurements were compared between the STN stimulation OFF and ON condition, in these experiments, there are no longitudinal studies examining the impact of electrode implantation per se on motor excitability. Here, we explored the effects of STN electrode implantation on resting motor thresholds (RMT), motor evoked potential (MEP) recruitment curves, and MEP onset latencies on 2 consecutive days before and shortly after STN surgery with the stimulator switched off, thus avoiding the effects of chronic DBS on the motor system, in 8 PD patients not taking any dopaminergic medication. After surgery, RMT and MEP recruitment curves were unchanged. In contrast, MEP onset latencies were significantly shorter when examined in relaxed muscles but were unchanged under preactivation. We hypothesize that postoperatively TMS pulses induced small currents in scalp leads underneath the TMS coil connecting the external stimulator with STN electrodes leading to inadvertent stimulation of fast‐conducting descending neural elements in the vicinity of the STN, thereby producing submotor threshold descending volleys. These “conditioning” volleys probably preactivated spinal motor neurons leading to earlier suprathreshold activation by the multiple corticospinal volleys produced by TMS of the motor cortex. These TMS effects need to be considered when interpreting results of excitability measurements in PD patients after implantation of STN electrodes. © 2006 Movement Disorder Society
Expression of the spermatogenic cell‐specific glyceraldehyde 3‐phosphate dehydrogenase (GAPDS) in rat testis
Authors: Welch Jeffrey E. , Barbee Randy R. , Magyar Patricia L. , Bunch Donna O. , O'Brien Deborah A.
Published: May 2006

The spermatogenic cell‐specific variant of glyceraldehyde 3‐phosphate dehydrogenase (GAPDS) has been cloned from a rat testis cDNA library and its pattern of expression determined. A 1,417 nucleotide cDNA has been found to encode an enzyme with substantial homology to mouse GAPDS (94% identity) and human GAPD2 (83% identity) isozymes. Northern blotting of rat tissue RNAs detected the 1.5 kb Gapds transcript in the testis and not in RNA from liver, spleen, epididymis, heart, skeletal muscle, brain, seminal vesicle, and kidney. The rat Gapds mRNA was first detected at day 29 of postnatal testis development, an age which coincides with the initial post‐meiotic differentiation of round spermatids. When isolated rat spermatogenic cell RNA was probed for Gapds expression, transcripts were detected only in round spermatids and condensing spermatids, but not in pachytene spermatocytes, demonstrating haploid expression of the Gapds gene. However, immunohistochemical staining of rat testis sections with anti‐GAPDS antisera did not detect GAPDS in round spermatids, but localized the protein only to stage XIII and later condensing spermatids as well as testicular spermatozoa, indicating that Gapds expression is translationally regulated. The current results are similar to those previously obtained for mouse GAPDS and human GAPD2, suggesting that reliable comparisons can be made between these species in toxicant screening and contraceptive development. Mol. Reprod. Dev. 1052–1060, 2006. Published 2006 Wiley‐Liss, Inc.
Characterization of the mRNA expression of StAR and steroidogenic enzymes in zebrafish ovarian follicles
Authors: Ings Jennifer S. , Van Der Kraak Glen J.
Published: May 2006

The objective of this study was to investigate the levels of expression of steroid biosynthetic enzymes and steroidogenic acute regulatory protein (StAR) at different stages of ovarian follicular development in zebrafish (Danio rerio), and to investigate the sites within the steroid biosynthetic pathway that may be regulated by gonadotropins. Ovarian follicles of sexually mature fish were separated into primary, previtellogenic, vitellogenic, and mature stages and the expression of StAR, P450 side chain cleavage (P450scc), 3β‐hydroxysteroid dehydrogenase (3β‐HSD), P450 hydroxylase/lyase (P450c17), 17β‐hydroxysteroid dehydrogenase type 1 (17β‐HSD1), 17β‐hydroxysteroid dehydrogenase type 3 (17β‐HSD3), and P450 aromatase (P450aromA) was determined by Real time RT‐PCR. The expression of all genes changed significantly as follicles grew, with a decrease in the expression of StAR, P450scc, 3β‐HSD and P450c17 with maturation, and an increase in the expression of 17β‐HSD3 during vitellogenesis and 17β‐HSD1 and P450aromA during previtellogenesis. In vitro incubation of vitellogenic follicles demonstrated that the expression of StAR, 17β‐HSD3, and P450aromA increased in response to hCG, and decreased in the absence of hCG. In contrast, the expression of P450scc, 3β‐HSD, P450c17, and 17β‐HSD1 remained constant between treatments and over time. Testosterone and estradiol production in the culture medium was stimulated by human chorionic gonadotropin (hCG). These experiments aid in the characterization of the roles and regulation of steroids throughout ovarian development, and suggest that gonadotropins play a key role in the regulation of StAR, 17β‐HSD3, and P450aromA in zebrafish. Mol. Reprod. Dev. 943–954, 2006. © 2006 Wiley‐Liss, Inc.
Antioxidant status of the lower oviduct in the chicken varies with age and dietary vitamin E supplementation
Authors: Breque Christelle , Surai Peter , Brillard Jean‐Pierre
Published: May 2006

Protection of sperm membranes against lipid peroxidation is a pre‐requisite to prolonged sperm storage, both in vivo and in vitro. As females from avian species can store spermatozoa in the utero‐vaginal junction (UVJ) for prolonged periods, we investigated the mechanisms involved in antioxidative protection of the plasma membrane of chicken sperm in this region. Comparisons of concentrations in nonenzymatic (α‐tocopherol, ascorbic acid, and GSH) and enzymatic (GSH‐Px, SOD) antioxidants among the vagina, UVJ and uterus of sexually mature chicken hens revealed tissue‐specific profiles, with higher ascorbic acid content and increased GSH‐Px and SOD activity in the UVJ compared to other regions of the lower oviduct (vagina, uterus). Deterioration of the antioxidant profile in the UVJ was observed in aging hens, but it was partially compensated by dietary supplementation with vitamin E (130 ppm). It is concluded that the chicken UVJ provides a complex defense barrier against lipid peroxidation of the sperm membrane during in vivo storage, which can be partially improved by dietary supplementation with vitamin E. The protective effects of this barrier decline over time during the reproductive season. Mol. Reprod. Dev. 1045–1051, 2006. © 2006 Wiley‐Liss, Inc.
Sexually dimorphic expression of secreted frizzled‐related (SFRP) genes in the developing mouse Müllerian duct
Authors: Cox Sam , Smith Lee , Bogani Debora , Cheeseman Michael , Siggers Pam , Greenfield Andy
Published: May 2006

In developing male embryos, the female reproductive tract primordia (Müllerian ducts) regress due to the production of testicular anti‐Müllerian hormone (AMH). Because of the association between secreted frizzled‐related proteins (SFRPs) and apoptosis, their reported developmental expression patterns and the role of WNT signaling in female reproductive tract development, we examined expression of Sfrp2 and Sfrp5 during development of the Müllerian duct in male (XY) and female (XX) mouse embryos. We show that expression of both Sfrp2 and Sfrp5 is dynamic and sexually dimorphic. In addition, the male‐specific expression observed for both genes prior to the onset of regression is absent in mutant male embryos that fail to undergo Müllerian duct regression. We identified ENU‐induced point mutations in Sfrp5 and Sfrp2 that are predicted to severely disrupt the function of these genes. Male embryos and adults homozygous for these mutations, both individually and in combination, are viable and apparently fertile with no overt abnormalities of reproductive tract development. Mol. Reprod. Dev. 1008–1016, 2006. © 2006 Wiley‐Liss, Inc.
Spermatocyte responses in vitro to induced DNA damage
Authors: Matulis Shannon , Handel Mary Ann
Published: May 2006

Spermatocytes normally sustain many meiotically induced double‐strand DNA breaks (DSBs) early in meiotic prophase; in autosomal chromatin, these are repaired by initiation of meiotic homologous‐recombination processes. Little is known about how spermatocytes respond to environmentally induced DNA damage after recombination‐related DSBs have been repaired. The experiments described here tested the hypothesis that, even though actively completing meiotic recombination, pachytene spermatocytes cultured in the absence of testicular somatic cells initiate appropriate chromatin remodeling and cell‐cycle responses to environmentally induced DNA damage. Two DNA‐damaging agents were employed for in vitro treatment of pachytene spermatocytes: γ‐irradiation and etoposide, a topoisomerase II (TOP2) inhibitor that results in persistent unligated DSBs. Chromatin modifications associated with DSBs were monitored after exposure by labeling surface‐spread chromatin with antibodies against RAD51 (which recognizes DSBs) and the phosphorylated variant of histone H2AFX (herein designated by its commonly used symbol, H2AX), γH2AX (which modifies chromatin associated with DSBs). Both γH2AX and RAD51 were rapidly recruited to irradiation‐ or etoposide‐damaged chromatin. These chromatin modifications imply that spermatocytes recruit active DNA damage responses, even after recombination is substantially completed. Furthermore, irradiation‐induced DNA damage inhibited okadaic acid‐induced progression of spermatocytes from meiotic prophase to metaphase I (MI), implying efficacy of DNA damage checkpoint mechanisms. Apoptotic responses of spermatocytes with DNA damage differed, with an increase in frequency of early apoptotic spermatocytes after etoposide treatment, but not following irradiation. Taken together, these results demonstrate modification of pachytene spermatocyte chromatin and inhibition of meiotic progress after DNA damage by mechanisms that may ensure gametic genetic integrity. Mol. Reprod. Dev. 1061–1072, 2006. © 2006 Wiley‐Liss, Inc.
Steroid hormones acutely regulate expression of a nudix protein‐encoding gene in the endometrial epithelium of sheep
Authors: Ing Nancy H. , Wolfskill Rebecca L. , Clark Shauna , deGraauw Jennifer A. , Gill Clare A.
Published: May 2006

Steroid hormones regulate endometrial gene expression to meet the needs of developing embryos. Our hypothesis is that steroid hormones transiently induce expression of genes in the endometrial epithelium to make the uterine environment different between the earliest days of pregnancy. We identified one such gene product using differential display‐polymerase chain reactions. The gene product that was strongly induced in ewes between day 3 and 6 of the estrous cycle was cloned and sequenced to identify it as encoding a member of the Nudix family of hydrolase enzymes. Northern blot analyses indicated that NUDT16 mRNA concentrations were elevated 10‐fold in the endometrium of sheep from day 5 to 9 of the estrous cycle and returned to basal levels by day 11. In assays of RNA samples from 15 different tissues from an adult ewe, the concentrations of NUDT16 mRNA were greatest in endometrium. In situ hybridization localized NUDT16 mRNA exclusively to the endometrial epithelial cells of the glands and uterine lumen. In ovariectomized ewes, NUDT16 mRNA was induced by a regimen of alternating estrogen and progesterone therapy designed to mimic the hormonal experiences of a ewe at day 6 of the estrous cycle. The final estrogen treatment in the regimen was critical to the expression of NUDT16 as well as progesterone receptor and estrogen receptor‐β genes. Characterization of the NUDT16 gene identified putative steroid hormone response elements, which can now be investigated to understand its unique pattern of regulation in the earliest days of pregnancy. Mol. Reprod. Dev. 967–976, 2006. © 2006 Wiley‐Liss, Inc.
Culturing in vitro produced blastocysts in sequential media promotes ES cell derivation
Authors: Liu J. , Schoonjans L. , Tielens S. , Speleman F. , Cornelissen M. , De Sutter P. , Dhont M. , Van der Elst J.
Published: May 2006

Embryonic stem (ES) cell lines are routinely derived from in vivo produced blastocysts. We investigated the efficiency of ES cells derivation from in vitro produced blastocysts either in monoculture or sequential culture. Zygotes from hybrid F1 B6D2 mice were cultured in vitro to the blastocyst stage in Potassium (K+) simplex optimised medium (KSOM) throughout or in KSOM and switched to COOK blastocyst medium on day 3 (KSOM–CBM). Blastocysts were explanted on a feeder layer of mitomycin C‐inactivated murine embryonic fibroblasts (MEF) in TX‐WES medium for ES cell derivation. Sequential KSOM–CBM resulted in improved blastocyst formation compared to KSOM monoculture. ES cells were obtained from 32.1% of explanted blastocsyts cultured in KSOM–CBM versus18.4% in KSOM alone. ES cell lines were characterized by morphology, expression of SSEA‐1, Oct‐4 and alkaline phosphatase activity, and normal karyotype. These results indicate that in vitro culture systems to produce blastocysts can influence the efficiency of ES cell line derivation. Mol. Reprod. Dev. 1017–1021, 2006. © 2006 Wiley‐Liss, Inc.
Addition of glutathione or thioredoxin to culture medium reduces intracellular redox status of porcine IVM/IVF embryos, resulting in improved development to the blastocyst stage
Authors: Ozawa Manabu , Nagai Takashi , Fahrudin Mokhamad , Karja Ni Wayan Kurniani , Kaneko Hiroyuki , Noguchi Junko , Ohnuma Katsuhiko , Kikuchi Kazuhiro
Published: May 2006

The present series of experiments investigated the effect of a reducing environment created by addition of reduced glutathione (GSH) or thioredoxin (TRX) to in vitro culture medium on the developmental competence of in vitro produced porcine embryos, and their intracellular redox status. Porcine cumulus–oocyte complexes were collected from ovaries matured and fertilized in vitro. The putative zygotes were then cultured for 6 days in modified NCSU‐37 medium with or without (control) GSH or TRX, and their developmental competence was evaluated. In addition, the intracellular redox status of the cultured embryos was compared quantitatively using an index based on the ratio of the intracellular GSH content relative to the intracellular H2O2 level. The proportion of embryos that developed to the blastocyst stage was significantly increased when 0.5 or 1.0 µM GSH (29.6% or 30.4%, P < 0.05 or 0.01, respectively) or 1.0 mg/ml TRX (30.6%, P < 0.01) was added to the medium compared to that without any supplementation (control; 20.1%). The intracellular redox status of embryos at the 8‐ to 12‐cell stage or the blastocyst stage in the group cultured in the presence of GSH or TRX was significantly reduced in comparison with the control (P < 0.05 to 0.001). Furthermore, administration of GSH or TRX enhanced the total cell number (from 48.3 to 49.2) and lowered the proportion of apoptotic cells (from 6.2% to 7.0%) in blastocysts compared with the control (cell number 39.3; apoptosis rate 11.1%, P < 0.05). These results suggest that GSH or TRX can improve the in vitro development of porcine embryos, while maintaining an intracellular reductive status. Mol. Reprod. Dev. 998–1007, 2006. © 2006 Wiley‐Liss, Inc.
A difference scheme for a parabolic system modelling the thermoelastic contacts of two rods
Authors: Sun Zhi‐zhong , Zhao Lei , Li Fu‐Le
Published: May 2006

In this article, we study a sequence of finite difference approximate solutions to a parabolic system, which models two dissimilar rods that each rod is fixed at one end and is free to expand or contact at the other end. A finite difference scheme is derived by the method of reduction of order on nonuniform mesh. The unique solvability, unconditional stability, and convergence of the difference scheme are proved. The convergence order is of order two in both time and space. The convergence of iterative algorithm for the difference scheme are also discussed. A numerical example is presented to demonstrate the theoretical results. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
Cribra orbitalia and porotic hyperostosis in a Greek colonial population (5th to 3rd centuries BC) from the Black Sea
Authors: Keenleyside A. , Panayotova K.
Published: May 2006

Cribra orbitalia and porotic hyperostosis in Greek skeletal remains have typically been attributed to a genetic anaemia, most notably thalassemia due to the presence of endemic malaria in the Mediterranean region. This paper reports the results of an analysis of cribra orbitalia and porotic hyperostosis in a Greek colonial population (5th to 3rd centuries BC) from the Black Sea. Archaeological evidence, stable isotopic data, and other skeletal indicators of physiological stress are examined to determine the most likely cause(s) of these lesions. While the possibility that some of the colonists of Apollonia suffered from thalassemia cannot be entirely discounted, the skeletal evidence examined in this study is not consistent with a diagnosis of thalassemia. We must therefore be cautious in assuming that cribra orbitalia and porotic hyperostosis in Greek skeletal remains, and indeed skeletal remains from any region where malaria was endemic in the past, is always indicative of this condition. Nutritional deficiencies and exposure to infectious diseases probably played an equally, if not more, important role in the development of these lesions. Copyright © 2006 John Wiley & Sons, Ltd.
Online learning: The potential for occupational therapy education
Authors: Hollis Vivien , Madill Helen
Published: May 2006

Online learning continues to have a significant impact on higher education. Increasingly students seek a combination of online learning and face‐to‐face instruction at undergraduate and graduate levels and occupational therapists ask for online continuing professional development opportunities. However, occupational therapy educators have been slow to adopt web‐based instructional technology. This paper presents background information on the use of web‐based learning in the general sphere of higher education and outlines the current range of usage in occupational therapy education. Research findings are presented to stimulate discussion regarding online learning and occupational therapy professional socialisation, student satisfaction and outcomes. There is a fine line between full and partial online course delivery, so research on technology‐enhanced campus‐based delivery is also included in the review. Evidence suggests that blending combinations of technologies with computer mediated learning enhances interaction and could address the higher order learning needs of professional programmes such as occupational therapy. Copyright © 2006 John Wiley & Sons, Ltd.
Engagement in occupations among men and women with schizophrenia
Authors: Bejerholm Ulrika , Eklund Mona
Published: May 2006

This study describes engagement in daily occupations of 10 women and 10 men with schizophrenia. A 24‐hour diary of time use and interview were used and analysed by content analysis. Three levels of occupational engagement were identified; (1) mainly disengaged throughout the day, (2) disengaged during some part of the day, and (3) largely engaged in occupations during the day. Each level of occupational engagement was related to a daily rhythm and a sense of meaning. The results of the content analysis showed that levels of engagement ranged from performing mostly quiet activities, alone, with little sense of meaning, to engaging in meaningful occupations that involved social interactions. In general female participants preferred activities in their home environment while males preferred activities outside their home environment. Although this study was limited by geographic and cultural boundaries, as well by the sample size, the results showed that being diagnosed as having schizophrenia does not necessarily mean having an impoverished lifestyle. Thus, it is important for occupational therapists to identify these variations in engagement in order to have a realistic point of departure in the evaluation process and in forming a therapeutic alliance with the client. In future research, methods need to be developed that can gather extensive information on how occupational engagement is related to health and well‐being in individuals diagnosed with schizophrenia. Copyright © 2006 John Wiley & Sons, Ltd.
Screening in early pregnancy for pre‐eclampsia using down syndrome quadruple test markers
Authors: Wald Nicholas J. , Morris Joan K. , Ibison Judith , Wu Tiesheng , George Lynne M.
Published: May 2006

Objectives

To estimate the screening performance of early second‐trimester prenatal serum markers for Down syndrome, in screening for the development of pre‐eclampsia, and analyse the uncertainty over its screening performance.

Methods

A nested case‐control study was carried out on 96 women with pre‐eclampsia and 5 controls for each case from among the women attending three hospitals in London for their prenatal care. Record linkage between computerized obstetric and screening databases identified women with pre‐eclampsia and unaffected control women. The stored frozen serum samples collected from these pregnancies between 15 and 22 weeks' gestation were retrieved and assayed for α‐fetoprotein (AFP), unconjugated estriol (uE3), total human chorionic gonadotrophin (hCG), free β‐hCG and inhibin‐A.

Results

Pre‐eclampsia was identified from the computerized obstetric records and confirmed by examination of the medical notes. In the pregnancies that went on to develop pre‐eclampsia, early second trimester inhibin‐A and hCG values were significantly raised and uE3 values were significantly lowered, while AFP values were not significantly altered. Using the Quadruple test markers (AFP, uE3, hCG (total or free β) and inhibin‐A), an estimated 34% of pregnancies that developed pre‐eclampsia were detected at a 5% false‐positive rate. If all the women who had pre‐eclampsia in a previous pregnancy (assuming a pre‐eclampsia prevalence of 4%) are considered as screen positive and the serum test is applied to the remaining women, then around 42% of pre‐eclamptic pregnancies would be detected at a 6.5% false‐positive rate. Pre‐eclampsia screening performance using the Quadruple test markers was materially better than that using the Triple test markers.

Conclusion

Adding screening for pre‐eclampsia to an existing Down syndrome screening programme using the Quadruple test markers is simple and worthwhile. It will detect over 40% of pregnancies with pre‐eclampsia at an acceptable false‐positive rate (about 6%) and with minimal additional costs. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnosis of de novo deletions of 8p23.1 or 15q26.1 in two fetuses with diaphragmatic hernia and congenital heart defects
Authors: López Isabel , Bafalliu Juan A. , Bernabé M. Carmen , García Francisco , Costa Miguel , Guillén‐Navarro Encarna
Published: May 2006

Objective

To show the importance of using high‐resolution chromosome analysis and FISH‐technique for finding subtle chromosomal lesions in prenatal diagnosis specially when there are abnormal ultrasound findings.

Methods

Ecographic examination of the fetus. GTG banded chromosome and FISH analysis using subtelomeric probes on amniocytes.

Results

We report two prenatal cases with congenital diaphragmatic hernia (CDH) and congenital heart defects (CHDs) with different deletions confirmed by FISH: del(8)(p23.1p23.1) and del(15)(q26.1).

Conclusion

These cases support the evidence that the regions 15q26.1 and 8p23.1 may play an important role in the development of the diaphragm. A deletion 8p23.1 or 15q26.1 should be considered whenever a CDH and/or a cardiac abnormality are detected on ultrasound. Copyright © 2006 John Wiley & Sons, Ltd.
National patterns of medication use during pregnancy
Authors: Lee Euni , Maneno Mary K. , Smith Leah , Weiss Sheila R. , Zuckerman Ilene H. , Wutoh Anthony K. , Xue Zhenyi
Published: May 2006

Purpose

To describe patterns of medication use during pregnancy in ambulatory care settings according to the U.S. Food and Drug Administration (FDA) pregnancy risk classification.

Methods

A cross‐sectional study of two national ambulatory care surveys, sampling all office visits made by pregnant women in 1999 and 2000, was conducted. Using the FDA pregnancy risk classification, patterns of medication use and predictive factors for FDA pregnancy risk D or X (D/X) medications were evaluated.

Results

In 1999 and 2000, about half of all pregnant visits had one or more medications. Among the total visits, FDA Class A was the majority (private = 65.7%; hospital = 79.5%; p < 0.05) followed by Class C (private = 26.5%; hospital = 36.4%; p < 0.05). Class D/X medications accounted for 6.4% and 2.9% of visits in private and hospital, respectively (p < 0.05). Medications with unknown pregnancy categories were predominant in the private setting (12.0% and 3.9%; p < 0.05). Age, insurance type, region, physician specialty, and number of medications were associated with a category D/X prescription. Among hospital visits, those from the West region and with private insurance were more likely to receive category D/X prescriptions. Number of medications was strongly associated with high‐risk drugs in both settings.

Conclusions

This study shows considerable medication use among pregnant women. The prevalence of visits with FDA pregnancy category D/X drugs was moderate, but still indicates exposure to high‐risk medications. Copyright © 2006 John Wiley & Sons, Ltd.