bluuebunny/crossref_metadata_2025 huggingface dataset:
Liver transplantation for a hilar inflammatory myofibroblastic tumor
Authors: Dasgupta D. , Guthrie A. , McClean P. , Davison S. , Luntley J. , Rajwal S. , Lodge J. P. A. , Prasad K. R. , Wyatt J. I. , Stringer M. D.
Published: September 2004

Abstract:  A 7‐yr‐old boy presented with obstructive jaundice secondary to an inflammatory myofibroblastic tumor centered on the hepatic hilum and extending into the liver. The tumor was further complicated by portal vein phlebitis and occlusion. Attempted resection of the tumor with portal vein reconstruction and bilioenteric drainage was unsuccessful and he required urgent orthotopic liver transplantation. In contrast to more peripheral inflammatory myofibroblastic tumors in the liver, hilar lesions are locally aggressive, causing occlusive portal phlebitis and biliary obstruction. Successful management may include the need for liver transplantation.
Mechanism of Dimer Formation of the 90‐kDa Heat‐Shock Protein
Authors: Nemoto Takayuki , Ohara‐Nemoto Yuko , Ota Minoru , Takagi Takashi , Yokoyama Kazushige
Published: September 2004

This study describes the mechanism of homodimer formation of the 90‐kDa heat‐shock protein (HSP90). In eukaryotic cells, there are two HSP90 isoforms, α and β, encoded by two separate genes. HSP90α exists predominantly as a homodimer, HSP90β mainly as a monomer. Analysis by native PAGE revealed that bacterially expressed HSP90α fused to glutathione S‐transferase (GST) existed as a high‐molecular‐mass oligomer, and was converted to a homodimer following removal of the fusion enzyme by thrombin cleavage. A deletion mutant, HSP90αD44–603, formed a monomer and an N‐terminal truncated mutant, HSP90α533–732, existed as a dimer, indicating that the dimer‐forming ability resides somewhere in the C‐terminal 200 amino acids. Limited proteolysis of the C‐terminal 200 amino acids of HSP90α with chymotrypsin produced the C‐terminal 16‐kDa fragment (Met628/Ala629–Asp732) and its adjacent more N‐terminal 13‐kDa fragment (Val542–Tyr627/Met628). Size‐exclusion HPLC and two‐dimensional PAGE analyses demonstrated that these two chymotryptic fragments bound each other. The C‐terminal 198 amino acids as well as the full‐length form of HSP90β revealed a lower dimer‐forming activity than HSP90α. Expression of the chimeric proteins at the C‐terminal 198 amino acids of the α and β isoforms further indicated that the 16 amino acid substitutions locating between amino acids 561 and 685 account for the impeded dimerization of HSP90β. A leucine zipper motif (Met402–Leu423) was unlikely to be involved in the dimer formation. Taken together, these results indicate that the dimeric structure of HSP90α is mediated by the C‐terminal 191 amino acids and consists of duplicate interactions of the C‐terminal region (Met628/Ala629–Asp732) of one subunit and the adjacent more N‐terminal region (Val542–Try627/Met628) of the other subunit.
An Alternative Role for the Src‐Homology‐Domain‐Containing Phosphotyrosine Phosphatase (SH‐PTP2) in Regulating Epidermal‐Growth‐Factor‐Dependent Cell Growth
Authors: Reeves Steven Anthony , Sinha Bibrama , Baur Inge , Reinhold Dirk , Harsh Griffith
Published: September 2004

The association of the src homology 2 (SH2) domain‐containing tyrosine phosphatase (SH‐PTP2) with the activated epidermal growth factor (EGF) and platelet‐derived growth factor receptors, as well as the insulin receptor substrate 1 and growth‐factor‐receptor‐bound protein 2 and its intrinsic tyrosine phosphatase activity suggests an important role for this phosphatase in signal transduction. Previous studies have shown a positive role for SH‐PTP2 in growth‐factor‐mediated cell signaling. We show here that SH‐PTP2 can also function to negatively regulate EGF‐mediated signal transduction in the human glioma cell line SNB19. We demonstrate this by showing that, in SNB19 cells, which lack the ability to proliferate in response to EGF but retain the ability to bind EGF and also activate the EGF receptor as well as allow for the association of SH‐PTP2 with the phosphorylated receptor, stable overexpression of an interfering SH‐PTP2 mutant can restore the ability of these cells to proliferate in response to EGF.
Phosphorylation State of the RNA Polymerase II C‐Terminal Domain (CTD) in Heat‐Shocked Cells
Authors: Venetianer Aniko , Dubois Marie‐Françoise , Nguyen Van Trung , Bellier Sylvain , Seo Sook‐Jae , Bensaude Olivier
Published: September 2004

RNA polymerase (RNAP) II is a multisubunit enzyme composed of several different subunits. Phosphorylation of the C‐terminal domain (CTD) of the largest subunit is tightly regulated. In quiescent or in exponentially growing cells, both the unphosphorylated (IIa) and the multiphosphorylated (IIo) subunits of RNAP II are found in equivalent amounts as the result of the equilibrated antagonist action of protein kinases and phosphatases.

In Drosophila and mammalian cells, heat shock markedly modifies the phosphorylation of the RNAP II CTD. Mild heat shocks result in dephosphorylation of the RNAP II CTD. This dephosphorylation is blocked in the presence of actinomycin D, as the CTD dephosphorylation observed in the presence of protein kinase inhibitors. Thus, heat shock might inactivate CTD kinases which are operative at normal growth temperatures, as some protein kinase inhibitors do. In contrast, severe heat shocks are found to increase the amount of phosphorylated subunit independently of the transcriptional activity of the cells.

Mild and severe heat shocks activate protein kinases, which then phosphorylate, in vitro and in vivo, the CTD fused to β‐galactosidase. Most of the heat‐shock‐activated CTD kinases present in cytosolic lysates co‐purify with the activated mitogen‐activated protein (MAP) kinases, p42mapk and p44mapk. The weak CTD kinase activation occurring upon mild heat shock might be insufficient to compensate for the heat inactivation of the already existing CTD kinases. However, under severe stress, the MAP kinases are strongly heat activated and might prevail over the phosphatases. A survey of different cells and different heat‐shock conditions shows that the RNAP II CTD hyperphosphorylation rates follow the extent of MAP kinase activation.

These observations lead to the proposal that the RNAP II CTD might be an in vivo target for the activated P42mapk and p44mapk MAP kinases.
A Cluster of Structural and Regulatory Genes for Light‐Induced Carotenogenesis in Myxococcus xanthus
Authors: Botella José A. , Murillo Francisco J. , Ruiz‐Vázquez Rosa
Published: September 2004

In the bacterium Myxococcus xanthus, several genes for carotenoid synthesis lie together at the carA‐carB chromosomal locus and are co‐ordinately activated by blue light. A 12‐kb DNA stretch from wild‐type M. xanthus has been sequenced that includes the entire carA‐carB gene cluster. According to sequence analysis, the cluster contains 11 different genes. Intergenic distances are very short or nil (implying translational coupling), giving further support to previous evidence indicating that most (or all) of the genes in the cluster form a single operon. At the promoter region, a potential –35 site for the binding of σ factors is found. However, the –10 region shows little similarity with analogous sites in other bacterial promoters. Five (possibly six) genes in the carA‐carB operon code for enzymes acting on early or late steps of the pathway for carotenoid synthesis. Other genes in the operon show no overall similarity with previously known genes. However, peptide stretches in the predicted products of two genes exhibit strong similarity with the DNA binding domain of the MerR family of transcriptional regulators. At least one of the predicted DNA‐binding domains is altered in a mutant strain affected in light‐regulation of the car genes.
Asters play only a dispensable role in the induction of the cleavage furrow in the blastomeres of early Xenopus embryos
Authors: Sakaida Tomoyuki , Inomata Shiho , Shinagawa Atsunori
Published: September 2004

Kuroda et al. (2001) of our laboratory have previously revealed that exposure of early Xenopus embryos to 150 mm urethane results in complete suppression of formation of the asters and the cleavage furrow, as well as significant reduction of the size of the spindle in the blastomeres, allowing only 1 or 2 cycles of mitosis but not cytokinesis. In the course of closer examination of the effect of urethane on the cleavage of blastomeres of early Xenopus embryos, we unexpectedly discovered that exposure of early Xenopus embryos to 75 mm urethane did not prevent cell division at all, though asters were not detected in the blastomeres. Instead, they contained a spindle that appeared rather normal. They also formed the diastema, a thin yolk‐free structure, which is considered to play an essential role in the induction of the cleavage furrow. Essentially the same results were obtained in the exposure of embryos to vinblastine, a well‐known microtubule inhibitor: exposure of embryos to 20 µg/mL vinblastine resulted in complete suppression of cleavage of the blastomeres, where formation of both the spindle and asters were perfectly suppressed. By contrast, exposure of embryos to 5 µg/mL vinblastine did not prevent cleavage in the blastomeres though asters were not detected, whereas the rather normal spindle was formed. Thus, there was a close correlation between the formation of the normal spindle, not asters, and that of the cell division furrow and the diastema in the blastomeres of early Xenopus embryos. We suggest that while the spindle plays an essential role, asters are likely to play only a dispensable role in the induction of the cleavage furrow in even very large cells like the blastomeres of early Xenopus embryos.
Paediatric outreach services
Authors: Williams ML , Smith AC
Published: September 2004

Abstract:  Paediatric outreach services are provided in Australia and overseas to regional and rural communities. More recently telehealth services have been established to support the delivery of paediatric services and clinical management at distant sites. It is suggested that with the large distances separating centres in Australia that a combination of telehealth clinics and outreach visits may provide the most efficient means of delivering paediatric specialty and subspecialty care to these centres.
Training in general paediatrics: Is it time for change?
Authors: Gunasekera H , Buckmaster A
Published: September 2004

Objective:  To determine current Australian general paediatrician's perceptions regarding the adequacy of their training particularly in the new morbidity (NM) area (developmental, behavioural and psychosocial). To ascertain if there is a perceived need to change training in this area, the level of support for change and to canvass opinion on how to achieve change.

Methods:  Australian general paediatricians were surveyed by mail in April 2002. The data obtained from those trained before and after the 1992 changes to training were compared by χ2 analysis.

Results:  The response rate was 76%. More than one in five new referrals were for NM problems according to 62% of the respondents. The majority (67%) of respondents reported that they were poorly or very poorly trained for NM work in contrast to a majority (82%) who rated that they were well or very well trained for general paediatric work (P < 0.001). Respondents believed that they were poorly or very poorly trained in the use of stimulants (74%), selective serotonin reuptake inhibitors (SSRIs) (93%), tricyclic antidepressants (TCAs) (79%) and clonidine (86%), despite a third of scripts being for one of these medications. The majority of all general paediatricians (90%) want changes to advanced training. Seminars/tutorials, organized visits to general paediatricians’ rooms and a mandatory 12 month NM term were the most highly supported options for change.

Conclusions:  In view of the prevalence of the NM problems, the perception of inadequate training and the overwhelming support for change it is time for new models of training to be developed and tested.
A method for the isolation of glomerular and tubulointerstitial endothelial cells and a comparison of characteristics with the human umbilical vein endothelial cell model
Authors: MCGINN STELLA , PORONNIK PHILIP , GALLERY EILEEN DM , POLLOCK CAROL A
Published: September 2004

Background:  Abnormalities in the structure and function of glomerular endothelial cells play a pivotal role in the development of progressive renal disease. The vascular abnormalities observed in the renal tubulointerstitium, however, correlate more strongly with progressive renal failure. Therefore, the successful isolation and culture of human renal microvascular endothelial cells from both the glomerulus and tubulointerstitium are paramount in studying renal disease models.

Methods and Results:  This study describes a simple and reproducible method for the isolation of human tubulointerstitial and glomerular endothelial cells by using immunomagnetic separation with anti‐platelet endothelial‐cell adhesion (anti‐PECAM‐1) Dyna beads, followed by manual weeding of mesangial and fibroblast contamination. No significant changes in morphological or immunohistochemical characteristics were observed up to passage two of culture. The in vitro characteristics of the endothelial cells were compared to the renal cortical endothelial cells in vivo and the standard human umbilical vein endothelial cell model (HUVECs). Similar to HUVECs, both populations of renal microvascular endothelial cells had a classical cobblestone appearance, stained positively for von Willebrand Factor and PECAM‐1 and negatively for antifibroblast surface antigen and anticytokeratin. Differences in the expression of von Willebrand Factor, Wiebel Palade bodies and Flk‐1 staining were observed between glomerular and tubulointerstitial endothelial cells. These immunohistochemical characteristics suggested that tubulointerstital endothelial cells were more closely aligned to HUVECS than to the glomerular endothelial cells. This observation indicated that HUVECs may be a suitable model for determining the tubulointerstitial endothelial response to systemic injury.

Conclusion:  In conclusion, a unique and novel method for the differential isolation of both glomerular and tubulointerstitial endothelial cells has been developed. Significantly, characterization of these populations suggests a role for HUVECS in the study of renal tubulointerstitial disease.
Determinants of native arteriovenous fistula blood flow
Authors: POLKINGHORNE KEVAN R , ATKINS ROBERT C , KERR PETER G
Published: September 2004

Background:  Determinants of native arteriovenous fistula (AVF) placement have been well studied. Little is known on whether these factors impact on subsequent blood flow (Qa) in the mature AVF.

Methods:  Arteriovenous fistula Qa and cardiac index (CI) were determined by ultrasound dilution. Multiple linear regression was used to assess independent predictors of AVF Qa.

Results:  Of the 148 patients available for the analysis, 68% were male, with 61% using a radiocephalic AVF. Aetiology of renal disease was: 38% glomerulonephritis (GN), 22% diabetes mellitus (DM), 9% hypertension/ischaemic (HTN) and 31% other. Thirty per cent had coronary artery disease (CAD), 10% cerebrovascular disease and 11% peripheral vascular disease (PVD). Median (iqr) Qa was 1185 mL/min (790–1650) and CI was 3.15 L/min per 1.73 m2 (2.60–3.93). On univariable analysis, log CI (0.98, P < 0.001), age (−0.1 per 10 years, P = 0.002), access position (upper vs lower 0.26, P = 0.003, PVD (−0.35, P = 0.015), CAD (−0.25, P = 0.008), and primary renal disease (DM vs GN, −0.35, P = 0.003, HTN vs GN, −0.34, P = 0.04) were associated with Qa. On multivariable analysis, CI (0.84, P < 0.001), access position (upper vs lower, 0.17, P = 0.018) and primary renal disease (DM vs GN, −0.26, P = 0.005, and HTN vs GN, −0.26, P = 0.038) remained significant predictors of AVF Qa.

Conclusion:  Once established, CI, AVF position and primary renal disease (hypertension/ischaemic and diabetes) are the major determinants of AVF Qa while female gender, CAD, PVD and body mass index were not significant determinants of Qa in this cohort.
EFFICACY OF MAGNIFYING COLONOSCOPY FOR THE DIAGNOSIS OF COLORECTAL NEOPLASIA: COMPARISON WITH HISTOPATHOLOGICAL FINDINGS
Authors: Ohta Akihiko , Tominaga Kenji , Sakai Yoshihiro
Published: September 2004

Background:  Some authors have reported a good correlation between the shape and arrangement in the oriﬁce of mucosal crypt (pit pattern) in the diagnosis of colorectal lesions and histopathological ﬁndings. However, there remains no good consensus on the deﬁnition of irregularity in conﬁgurations.

Methods:  We studied 110 colorectal neoplasia of 110 cases that were examined using a magnifying colonoscope and resected endoscopically or surgically between 2001 and 2003. We divided the lesions into two groups according to Fujii's classiﬁcation as follows: type Non‐V showed type III or IV by Kudo's classiﬁcation and irregular pits not occurring in a demarcated area; and type V showed irregular pits, which occurred in a demarcated area in addition to type VN by Kudo. The diagnosis by this classiﬁcation correlated with the histopathological ﬁndings. We also addressed the causes of misdiagnosis in comparison with histopathological ﬁndings.

Results:  The diagnostic accuracy for Non‐V and V was 95.1% and 82.1%, respectively. Lesions classiﬁed as V showed a signiﬁcant correlation. Histologically, carcinoma consisted of high‐grade atypia (P < 0.0001), an erosive change of surface epithelium (P < 0.0001) and the appearance of desmoplastic reactions (P = 0.002) in comparison with Non‐V. Misdiagnosis was likely due to differences in the grade of atypia between superﬁcial and deeper glands and explainable erosive changes on the surface, as well as simple misreading of the pit pattern.

Conclusion:  Diagnosis of colorectal neoplasia by magnifying colonoscope using our classiﬁcation was useful for evaluating the depth of invasion and correlated well with histopathological ﬁndings.
Pricing Access to a Monopoly Input
Authors: Sibley David S. , Doane Michael J. , Williams Michael A. , Tsai Shu‐Yi
Published: September 2004

What price should downstream entrants pay a vertically integrated incumbent monopoly for use of its assets? Courts, legislators, and regulators have at times mandated that incumbent monopolies lease assets required for the production of a retail service to entrants in efforts to increase the competitiveness of retail markets. This paper compares two rules for pricing such monopoly inputs: marginal cost pricing (MCP) and generalized efficient component pricing rule (GECPR). The GECPR is not a fixed price, but is a rule that determines the input price to be paid by the entrant from the entrant's retail price. Comparing the retail market equilibrium under MCP and GECPR, the GECPR leads to lower equilibrium retail prices. If the incumbent is less efficient than the entrant, the GECPR also leads to lower production costs than does the MCP rule. If the incumbent is more efficient than the entrant, however, conditions may exist in which MCP leads to lower production costs than does the GECPR. The analysis is carried out assuming either Bertrand competition, quantity competition, or monopolistic competition between the incumbent and entrant in the downstream market.
A Theory of Broadcast Media Concentration and Commercial Advertising
Authors: Cunningham Brendan M. , Alexander Peter J.
Published: September 2004

We analyze a model in which the interaction of broadcasters, advertisers, and consumers determines the level of nonadvertising broadcasting produced and consumed. Our main finding is that an increase in concentration in broadcast media industries may lead to a decrease in the total amount of nonadvertising broadcasting. The strength of this inverse relationship depends, in part, on the behavioral response of the consumers to changes in advertising intensities. We also present a numerical general equilibrium solution to our model and demonstrate a positive relationship between consumer welfare and the number of firms in the broadcast industry.
Severance Payments and Unemployment Insurance: A Commitment Issue
Authors: Martin Richard , Mongrain Steeve , Parkinson Sean
Published: September 2004

In the event of a job termination, many workers receive severance payments from their employer, in addition to publicly provided unemployment insurance (UI). In the absence of a third party enforcer, contracts featuring severance payments must be supported by an implicit self‐enforcing contract. Workers believe employers will make severance payments only if it is in their best interest ex post. If firms discount the future deeply, they will reduce the severance payment they offer, in order to relax their incentive constraint. Workers are forced to bear risk, and too many workers are laid off. We show that a well‐designed public UI system can correct these distortions.
Contribution compliance in central and eastern European countries: Some relevant issues
Authors: Stanovnik Tine
Published: September 2004

A number of central and eastern European countries reformed their pension systems during the 1990s. In the preparation of these reforms, insufficient attention was given to the institutional and administrative aspects — and the related problem of contribution collection. This article presents a broad overview of what has actually been happening with contribution collection and contribution compliance in these countries. It also provides a brief description of administrative changes relevant for contribution collection.
Cytokines ‐ killers in the brain?
Authors: Rothwell Nancy J.
Published: September 2004

Given at the Meeting of the Physiological Society held at the University of Southampton on 10 September 1998
Characterization of spindle cell component of ferret (Mustela putorius furo) adrenal cortical neoplasms – correlation to clinical parameters and prognosis
Authors: Newman S. J. , Bergman P. J. , Williams B. , Scase T. , Craft D.
Published: September 2004

Adrenal cortical epithelial tumours are common in ferrets. A variant tumour type with prominent spindle cell proliferation has been identified. We characterized these variant tumours with light microscopy and immunohistochemical analysis and correlate these features to clinical parameters and prognosis.

We classified 24 ferret adrenal cortical masses with recognizable spindle cell proliferation obtained from the AMC and AFIP databases, based on percentage of spindle cells present and features of malignancy. These masses were separated into hyperplastic nodules and adenomas (both with 1–24% spindle cells), ‘mixed’ adenomas (≥25% spindle cells), adenocarcinomas (1–24%) and ‘mixed’ adenocarcinomas (≥25% spindle cells). Tumours were evaluated immunohistochemically for smooth muscle actin (SMA) and estrogen receptor (ER) expression. Disease‐free interval (DFI) and survival time (ST) were calculated using Kaplan–Meier product limit method.

Of 24 cases of spindle cell variant adrenal tumours, one was a hyperplastic nodule, 10 were adenomas, three were ‘mixed’ adenomas, six were adenocarcinomas and four were ‘mixed’ adenocarcinomas. The proliferative spindle cell cytoplasm was SMA‐positive (smooth muscle myocyte origin). ER positivity, seen in nine of 24 cases, was restricted to adenocarcinomas, ‘mixed’ adenomas and ‘mixed’ adenocarcinomas. DFI and ST were significantly reduced in ‘mixed’ adenocarcinomas or tumours with ER expression. DFI was significantly reduced in tumours with marked smooth muscle.

The spindle cell component of these variant adrenal tumours is smooth muscle in origin. The presence of abundant smooth muscle, a more malignant histologic grade (‘mixed’ adenocarcinomas) and ER expression are significantly positively correlated to both decreased DFI and decreased ST.
Metastatic synovial cell sarcoma in two cats
Authors: Liptak J. M. , Withrow S. J. , Macy D. W. , Frankel D. J. , Ehrhart E. J.
Published: September 2004

Synovial cell sarcoma (SCS) with metastasis to the regional lymph node was diagnosed in two cats. Synovial cell sarcomas are rare in cats and metastatic SCS has not previously been reported. In both cases, treatment consisted of limb amputation and adjuvant doxorubicin. Local tumour recurrence and pulmonary metastases were diagnosed in one cat 316 days postoperatively. This cat died of chronic renal failure 444 days after limb amputation. The second cat died of an acute pulmonary thromboembolism 41 days postoperatively without evidence of local tumour recurrence or metastatic disease.
Washing away poverty: Water, democracy and gendered poverty eradication in South Africa
Authors: Schreiner Barbara , Mohapi Ndileka , Van Koppen Barbara
Published: September 2004

This article discusses ways in which the South African Government and grassroots organizations envisage and implement democracy achieved since 1994 in the field of water resources management. The focus is on the democratic, political and economic freedom and equality in resource rights for poor black women, who are central to poverty eradication. While the new water policy and law provide an enabling framework for achieving these goals, implementation on the ground encounters both new opportunities and constraints. This is illustrated by several cases of establishing South Africa's new water management institutions: catchment management agencies and water user associations. The important nexus between state‐led democratization of water resources management and bottom‐up grassroots movements is also discussed. The article concludes that the Government's affirmative and targeted intervention is indispensable for redressing gender inequalities and eradicating poverty.
Dominant and Marginalized Discourses in Interracial Couples' Narratives: Implications for Family Therapists
Authors: Killian Kyle D.
Published: September 2004

This study explores interracial couples' family histories, their experiences of their life together, and the dominant and subordinate discoures employed in negotiating racial and ethnic differences. Ten black‐white couples were interviewed individually and conjointly. Dominant discourses that emerged from the couples' narratives included those of homogamy, hypersensitivity of persons of color, and the insignificance of familial and societal history. Interracial partners also simultaneously subverted these prevailing ideologies by voicing expriences associated with life at the margins of the society. Dominant and subordinate discoureses used by therapists and interracial couples in the therapy room are examined to integrate marginalized “truths” crucial to effective work with interracial couples and persons of color.
Measurement accuracy of reconstructed 2‐D images obtained by multi‐slice helical computed tomography
Authors: Naitoh Munetaka , Katsumata Akitoshi , Nohara Eiji , Ohsaki Chiaki , Ariji Eiichiro
Published: September 2004

Abstract: The present dental reconstructed computed tomography (CT) images consist of continuously piled‐up axial CT images that are perpendicular to the axial CT plane. In the mandibular posterior region, the angles of designed implants frequently differ from the angles perpendicular to the axial CT plane and the measurement of mandibular height is inaccurate. This study was performed to clarify the measurement accuracy of double‐oblique reconstructed images in multi‐slice helical CT, using dried mandibles. The mandibular height was measured from the alveolar crest immediately below the aluminum tube to the superior border of the mandibular canal using the double‐oblique reconstructed images and the micro‐CT average images of three semi‐lateral dried mandibles. The mean of the differences between the double‐oblique reconstructed images with a table pitch of 1.5 in a helical scan and the micro‐CT average images was 0.31 mm. It is concluded that the accuracy of the double‐oblique reconstructed image measurements with helical scan is high. So this double‐oblique program can be applied to the imaging diagnosis in dental implant treatment.
Correlation of peri‐implant health and myeloperoxidase levels: a cross‐sectional clinical study
Authors: Liskmann Stanislav , Zilmer Mihkel , Vihalemm Tiiu , Salum Olev , Fischer Krista
Published: September 2004

Objectives: At present, there are no diagnostic tools that permit early detection of peri‐implantitis. The purpose of this cross‐sectional study was to evaluate the correlation of myeloperoxidase (MPO) levels with traditional periodontal clinical parameters around dental implants including peri‐implant pocket probing depth (PPD), gingival index (GI) and bleeding on probing (BOP), since MPO has been associated with destruction of periodontal tissues.

Material and methods: Twenty‐four healthy adult volunteers (9 men and 15 women) with 64 Ankylos® Biofunctional implants (DentsplyFriadent, Mannheim, Germany) were recruited from Tallinn Dental Clinic. Biochemical and clinical parameters evaluated were the following ones: the level of MPO in the peri‐implant sulcus fluid (PISF) (an analog for gingival crevicular fluid in natural teeth), PPD (mm), GI (0,1,2 or 3), and BOP (0 or 1).

Results and conclusion: In comparison to the clinically healthy implants, total amounts of MPO were significantly higher in PISF collected around implants with inflammatory lesions. In addition, the levels of MPO were correlated with the clinical parameters. The results confirm the similarity of the inflammatory response of tissues surrounding implants and natural teeth, and suggest that MPO could be promising marker of inflammation around dental implants.
Influence of transport stress on serum cortisol and thyroid hormones in pigs with Halothane gene
Authors: YOSHIOKA Gou , IMAEDA Noriaki , TORIMOTO Yasuo , OHTANI Tsuyoshi , HAYASHI Kunioki
Published: September 2004

The influence of transport stress on rectal temperature, respiratory rate and serum concentrations of cortisol, thyroxine and triiodothyronine (T3) in normal pigs (NN) and in heterozygous (Nn) pigs with Halothane gene (n), a major gene that causes the pale, soft, exudative meat (PSE), were examined in a hot environment (32–34°C). Easily releasable myofilament content of Longissimus dorsi taken by needle biopsy was also measured as an index of myofibrillar disassembly. Rectal temperature and respiratory rate were significantly increased by the transport. However, the influence was higher (P < 0.01) in Nn pigs. Serum concentration of cortisol was increased (P < 0.01) by the transport despite the genotypes. Serum concentration of T3 was not changed by the transport in Nn pigs, whereas in NN pigs it was significantly decreased after the transport (P < 0.01). Easily releasable myofilament content after the transport was higher in Nn pigs than that of NN pigs (P < 0.05). These results suggest that response of thyroid function might relate to the stimulation of muscle proteolysis and PSE in Nn pigs under stressful conditions.
MAGNETIC RESONANCE IMAGING OF ARTICULAR PROCESS JOINT GEOMETRY AND INTERVERTEBRAL DISK DEGENERATION IN THE CAUDAL LUMBAR SPINE (L5–S1) OF DOGS WITH CLINICAL SIGNS OF CAUDA EQUINA COMPRESSION
Authors: Rossi F. , Seiler G. , Busato A. , Wacker C. , Lang J.
Published: September 2004

The geometry of the lumbosacral region has been suspected to play a role in the development of degenerative lumbosacral stenosis in the dog. In this study, 50 dogs (21 German Shepherd dogs and 29 dogs of other breeds) with clinical signs of cauda equina compression were studied by magnetic resonance (MR) imaging. The orientation of the articular process joints in the L5‐S1 region and the angle difference between two adjacent motion segments were calculated. Intervertebral disc degeneration of the same region was identified and classified in four stages. A positive association between MR‐imaging stage and articular process joint angle difference in the transverse plane was found in the two groups of animals. German Shepherd dogs and dogs of other breeds had different geometry of the lumbosacral region with different articular process joint angles in the transverse plane and statistically different stages of disc degeneration.
Performance of Strongly Bowed Stators in a Four-Stage High-Speed Compressor
Authors: Fischer Axel , Riess Walter , Seume Joerg R.
Published: September 2004

The FVV sponsored project “Bow Blading” (cf. acknowledgments) at the Turbomachinery Laboratory of the University of Hannover addresses the effect of strongly bowed stator vanes on the flow field in a four-stage high-speed axial compressor with controlled diffusion airfoil (CDA) blading. The compressor is equipped with more strongly bowed vanes than have previously been reported in the literature. The performance map of the present compressor is being investigated experimentally and numerically. The results show that the pressure ratio and the efficiency at the design point and at the choke limit are reduced by the increase in friction losses on the surface of the bowed vanes, whose surface area is greater than that of the reference (CDA) vanes. The mass flow at the choke limit decreases for the same reason. Because of the change in the radial distribution of axial velocity, pressure rise shifts from stage 3 to stage 4 between the choke limit and maximum pressure ratio. Beyond the point of maximum pressure ratio, this effect is not distinguishable from the reduction of separation by the bow of the vanes. Experimental results show that in cases of high aerodynamic loading, i.e., between maximum pressure ratio and the stall limit, separation is reduced in the bowed stator vanes so that the stagnation pressure ratio and efficiency are increased by the change to bowed stators. It is shown that the reduction of separation with bowed vanes leads to a increase of static pressure rise towards lower mass flow so that the present bow bladed compressor achieves higher static pressure ratios at the stall limit.
A Numerical Investigation of the Flow Mechanisms in a High Pressure Compressor Front Stage With Axial Slots
Authors: Wilke Ingo , Kau Hans-Peter
Published: September 2004

This paper describes the impact of axial slots on the flow field in a transonic rotor blade row. The presented results are completely based on time-accurate three-dimensional numerical simulations of a high pressure compressor front stage with and without casing treatment. Two different axial positions of a casing treatment consisting of axial slots were tested for their impact on flow stability and efficiency. The first tested position (configuration 1) was chosen in a conventional way. The slots extend approximately from the leading up to the trailing edge of the rotor blades. As expected, the simulations of the compressor stage with this configuration showed a significant increase in flow stability near surge compared to the solid wall case. However, a non-negligible decrease in efficiency is also observed. Analyses of flow interactions between casing treatment and rotor blade rows under transonic conditions lead to the general conclusion that the stabilizing effect of circumferential grooves or axial slots mainly results from their impact on the tip leakage flow and its resulting vortex. A characteristic vortex inside the slots is observed in the simulations with the conventionally positioned casing treatment. This vortex removes fluid out of downstream parts of the blade passage and feeds it back into the main flow further upstream. The resulting impact on the tip leakage flow is responsible for the increased flow stability. However, the interaction between the configuration 1 casing treatment flow and the blade passage flow results in a significant relocation of the blade passage shock in the downstream direction. This fact is a main explanation for the observed decrease in compressor efficiency. A second slot position (configuration 2) was tested with the objective to improve compressor efficiency. The casing treatment was shifted upstream, so that only 25% of the blade chord remained under the slots. The simulations carried out demonstrate that this shift positively affects the resulting efficiency, but maintains the increased level of flow stability. A time-accurate analysis of the flow shows clearly that the modified casing treatment stabilizes the tip leakage vortex and reduces the influence on the flow inside the blade passage.
Intermittency Transport Modeling of Separated Flow Transition
Authors: Vicedo J. , Vilmin S. , Dawes W. N. , Savill A. M.
Published: September 2004

An intermittency transport model is proposed for modeling separated-flow transition. The model is based on earlier work on prediction of attached flow bypass transition and is applied for the first time to model transition in a separation bubble at various degrees of freestream turbulence. The model has been developed so that it takes into account the entrainment of the surrounding fluid. Experimental investigations suggest that it is this phenomena which ultimately determines the extent of the separation bubble. Transition onset is determined via a boundary layer correlation based on momentum thickness at the point of separation. The intermittent flow characteristic of the transition process is modeled via an intermittency transport equation. This accounts for both normal and streamwise variation of intermittency and hence models the entrainment of surrounding flow in a more accurate manner than alternative prescribed intermittency models. The model has been validated against the well-established T3L semicircular leading edge flat plate test case for three different degrees of freestream turbulence characteristic of turbomachinery blade applications.
The Nimitz Freeway Collapse
Authors: Feldman Bernard J.
Published: September 2004

One of the most tragic sights created by the Loma Prieta earthquake of Oct. 17, 1989, was the collapse of the double-deck Nimitz Freeway (the Cypress Street Viaduct on Interstate 880) just south and east of the San Francisco-Oakland Bay Bridge in Oakland. Along a 1.4-km north-south stretch, the upper deck of the freeway fell on top of the lower deck of the freeway, killing 42 motorists (see Fig. 1). Even though the earthquake occurred during rush hour (5:04 p.m.), traffic was extremely light that day because the third game of the World Series between the Oakland Athletics and the San Francisco Giants was about to begin and many commuters were already at home in front of their television sets.
The Siren
Authors: Greenslade Thomas B.
Published: September 2004

One evening in the fall of 1964, early in my first semester of teaching physics at Kenyon College, I decided to try out the siren in Fig. 1. In those days we had a compressed air line in the lecture hall, and I connected the siren to it. It gave out a satisfyingly loud scream like a legion of cats having their tails stepped on, and within seconds the entire campus security force (two men) arrived in the lecture hall asking about the emergency. I have not done the demonstration since. The siren is a blessing and a curse of modern life. It is used to warn us of approaching storms, and also of overtaking police cars. However, it began as a scientific instrument in the first part of the 19th century.1
Defining T-Cell-Mediated Immune Responses in Rotavirus-Infected Juvenile Rhesus Macaques
Authors: Sestak K. , McNeal M. M. , Choi A. , Cole M. J. , Ramesh G. , Alvarez X. , Aye P. P. , Bohm R. P. , Mohamadzadeh M. , Ward R. L.
Published: September 2004

The appearance of virus-specific CD4
+
and/or CD8
+
T lymphocytes in peripheral blood of captive juvenile rhesus macaques (
Macaca mulatta
) was observed following rotavirus infection. These cell-mediated immune responses were measured following experimental or natural infection after rotavirus was isolated from stool specimens of asymptomatic animals. The virus isolated was a new strain of simian rotavirus that we named TUCH (for Tulane University and Cincinnati Children's Hospital). Restimulation of peripheral T lymphocytes by inactivated double- or triple-layered TUCH rotavirus particles containing either VP6 or VP4 and VP7 on their respective surfaces resulted in increased quantities of interleukin-6 (IL-6) and IL-12 in cell culture supernatants. Recall responses to rotavirus by CD4
+
and CD8
+
T lymphocytes were associated with accumulation of intracellular IL-6 and gamma interferon. Antigen presentation of TUCH rotavirus to lymphocytes was mediated via differentiated cultures of monocyte-derived dendritic (HLA-DR
+
) cells. This is the first report demonstrating cell-mediated immune responses to rotavirus in nonhuman primates. Further exploration of rhesus macaques in vaccine trials with human rotavirus vaccine candidates is the major objective of future studies.
Increased Ubiquitination and Other Covariant Phenotypes Attributed to a Strain- and Temperature-Dependent Defect of Reovirus Core Protein μ2
Authors: Miller Cathy L. , Parker John S. L. , Dinoso Jason B. , Piggott Caroline D. S. , Perron Michel J. , Nibert Max L.
Published: September 2004

Reovirus replication and assembly are thought to occur within cytoplasmic inclusion bodies, which we call viral factories. A strain-dependent difference in the morphology of these structures reflects more effective microtubule association by the μ2 core proteins of some viral strains, which form filamentous factories, than by those of others, which form globular factories. For this report, we identified and characterized another strain-dependent attribute of the factories, namely, the extent to which they colocalized with conjugated ubiquitin (cUb). Among 16 laboratory strains and field isolates, the extent of factory costaining for cUb paralleled factory morphology, with globular strains exhibiting higher levels by far. In reassortant viruses, factory costaining for cUb mapped primarily to the μ2-encoding M1 genome segment, although contributions by the λ3- and λ2-encoding L1 and L2 genome segments were also evident. Immunoprecipitations revealed that cells infected with globular strains contained higher levels of ubiquitinated μ2 (Ub-μ2). In M1-transfected cells, cUb commonly colocalized with aggregates formed by μ2 from globular strains but not with microtubules coated by μ2 from filamentous strains, and immunoprecipitations revealed that μ2 from globular strains displayed higher levels of Ub-μ2. Allelic changes at μ2 residue 208 determined these differences. Nocodazole treatment of cells infected with filamentous strains resulted in globular factories that still showed low levels of costaining for cUb, indicating that higher levels of costaining were not a direct result of decreased microtubule association. The factories of globular strains, or their μ2 proteins expressed in transfected cells, were furthermore shown to gain microtubule association and to lose colocalization with cUb when cells were grown at reduced temperature. From the sum of these findings, we propose that μ2 from globular strains is more prone to temperature-dependent misfolding and as a result displays increased aggregation, increased levels of Ub-μ2, and decreased association with microtubules. Because so few of the viral strains formed factories that were regularly associated with ubiquitinated proteins, we conclude that reovirus factories are generally distinct from cellular aggresomes.
Signaling through the Prostaglandin I2Receptor IP Protects against Respiratory Syncytial Virus-Induced Illness
Authors: Hashimoto Koichi , Graham Barney S. , Geraci Mark W. , FitzGerald Garret A. , Egan Karine , Zhou Weisong , Goleniewska Kasia , O'Neal Jamye F. , Morrow Jason D. , Durbin Russell K. , Wright Peter F. , Collins Robert D. , Suzutani Tatsuo , Peebles R. Stokes
Published: September 2004

The role of prostanoids in modulating respiratory syncytial virus (RSV) infection is unknown. We found that RSV infection in mice increases production of prostaglandin I2(PGI2). Mice that overexpress PGI2synthase selectively in bronchial epithelium are protected against RSV-induced weight loss and have decreased peak viral replication and gamma interferon levels in the lung compared to nontransgenic littermates. In contrast, mice deficient in the PGI2receptor IP have exacerbated RSV-induced weight loss with delayed viral clearance and increased levels of gamma interferon in the lung compared to wild-type mice. These results suggest that signaling through IP has antiviral effects while protecting against RSV-induced illness and that PGI2is a potential therapeutic target in the treatment of RSV.
Structural Properties of a Multifunctional T-Shaped RNA Domain That Mediate Efficient Tomato Bushy Stunt Virus RNA Replication
Authors: Ray Debashish , Na Hong , White K. Andrew
Published: September 2004

In positive-strand RNA viruses, 5′ untranslated regions (5′ UTRs) mediate many essential viral processes, including genome replication. Previously, we proposed that the 5′-terminal portion of the genomic leader sequence of
Tomato bushy stunt virus
(TBSV) forms an RNA structure containing a 3-helix junction, termed the T-shaped domain (TSD). In the present study, we have carried out structure-function analysis of the proposed TSD and have confirmed an important role for this domain in mediating efficient viral RNA amplification. Using a model TBSV defective interfering RNA replicon and a protoplast system, we demonstrated that various TSD subelements contribute to the efficiency of viral RNA replication. In particular, the stabilities of all three stems (S1, S2, and S4) forming the 3-helix junction are important, while stem-loop 3—a terminal extension of S2—is largely dispensable. Additionally, some of the sequences forming the 3-helix junction are required in an identity-dependent manner. Thus, both secondary structure and nucleotide identity are important for TSD-mediated viral RNA replication. Importantly, these results are fully consistent with the dual functions we defined previously for the sequences corresponding to loops 3 and 4, respectively, in facilitating 5′ cap- and 3′ poly(A) tail-independent translation of the genome by forming a loop-loop interaction with the 3′-proximal translational enhancer and in mediating viral RNA replication through formation of a pseudoknot with the adjacent downstream RNA domain. Also, since comparable TSDs and associated interactions are predicted in the 5′ UTRs of all sequenced
Aureusvirus
genomes, members of at least one other genus in the family
Tombusviridae
appear to utilize this type of multifunctional RNA domain.
Dual Role of Prostratin in Inhibition of Infection and Reactivation of Human Immunodeficiency Virus from Latency in Primary Blood Lymphocytes and Lymphoid Tissue
Authors: Biancotto Angélique , Grivel Jean-Charles , Gondois-Rey Françoise , Bettendroffer Lise , Vigne Robert , Brown Stephen , Margolis Leonid B. , Hirsch Ivan
Published: September 2004

To design strategies to purge latent reservoirs of human immunodeficiency virus type 1 (HIV-1), we investigated mechanisms by which a non-tumor-promoting phorbol ester, prostratin, inhibits infection of CD4+T lymphocytes and at the same time reactivates virus from latency. CD4+T lymphocytes from primary blood mononuclear cells (PBMC) and in blocks of human lymphoid tissue were stimulated with prostratin and infected with HIV-1 to investigate the effects of prostratin on cellular susceptibility to the virus. The capacity of prostratin to reactivate HIV from latency was tested in CD4+T cells harboring preintegrated and integrated latent provirus. Prostratin stimulated CD4+T cells in an aberrant way. It induced expression of the activation markers CD25 and CD69 but inhibited cell cycling. HIV-1 uptake was reduced in prostratin-stimulated CD4+T PBMC and tissues in a manner consistent with a downregulation of CD4 and CXCR4 receptors in these systems. At the postentry level, prostratin inhibited completion of reverse transcription of the viral genome in lymphoid tissue. However, prostratin facilitated integration of the reverse-transcribed HIV-1 genome in nondividing CD4+T cells and facilitated expression of already integrated HIV-1, including latent forms. Thus, while stimulation with prostratin restricts susceptibility of primary resting CD4+T cells to HIV infection at the virus cell-entry level and at the reverse transcription level, it efficiently reactivates HIV-1 from pre- and postintegration latency in resting CD4+T cells.