bluuebunny/crossref_metadata_2025 huggingface dataset:
FORMATION OF NUCLEOSIDE DIPHOSPHATE MONOSACCHARIDES (NDP‐SUGARS) BY THE AGAROPHYTE PTEROCLADIA CAPILLACEA (RHODOPHYCEAE)1
Authors: Manley Steven L. , Burns Deborah J.
Published: October 2004

The following nucleoside diphosphate monosaccharides (sugar nucleotides) were identified by HPLC from Pterocladia capillacea Born and Thur.: ADP‐glucose, UDP‐glucose, UDP‐d‐galactose, and GDP‐glucose + mannose. GDP‐l‐galactose was not identified due to the lack of a standard. Several extraction methods were evaluated for their efficacy. A freeze/ thaw (liquid N2) step fallowed by formic acid (1 M) extraction, reduced pressure evaporation, and solubilization in water was the preferred method. Differences in media nitrate that resulted in different tissue‐N levels (1.8, 2.3, and 3.5% dry wt) and agar yields (34, 31, and 28% dry wt, respectively) also resulted in a marked difference in UDP‐d‐galactose and ADP‐glucose tissue levels (decrease with increasing tissue‐N) while the levels of the other sugar nucleotide agar precursors remained unchanged. Activities of UDP‐glucose, GDP‐glucose, and GDP‐mannose pyrophosphorylases, and UDP‐D‐glucose‐4‐epimerase were detected in cell‐free extracts using unlabeled and 14C‐labeled substrates. This study‐strongly supports the proposition that the d‐galactose component of agar is synthesized via G‐1‐P → UDP‐glucose→ UDP‐d‐galactose and that, the l‐galactoae component is produced via mannose‐1‐P → GDP‐mannose → GDP‐l‐galactose.
MFB‐1, an F‐box‐type ubiquitin ligase, regulates TGF‐β signalling
Authors: Aoyama Yukako , Urushiyama Seiichi , Yamada Misato , Kato Chikako , Ide Hiroko , Higuchi Satoshi , Akiyama Tetsu , Shibuya Hiroshi
Published: October 2004

TGF‐β signalling regulates cell growth, differentiation, morphogenesis and apoptosis. MAFbx/Atrogin‐1 has been identified as a regulator for skeletal muscle atrophy and encodes an F‐box‐type E3 ubiquitin ligase. However, little is known about how MAFbx/Atrogin‐1 regulates cellular signalling. Here, we identify and genetically characterize MFB‐1, a MAFbx/Atrogin‐1 homologue fromCaenorhabditis elegans. Themfb‐1deletion mutant significantly enhanced the dauer constitutive (Daf‐c) phenotype caused by mutations in the DAF‐7/TGF‐β‐like signalling pathway, but not the DAF‐2/insulin receptor‐like signalling pathway. Conversely, the Daf‐c phenotypes of DAF‐7 pathway mutants were partially suppressed bymfb‐1cDNA transgenes. Therefore, MFB‐1 acts genetically downstream in the DAF‐7 pathway. A mfb‐1::GFP fusion was found to be expressed in the nervous system, hypodermis and intestine and overlapped expression of many DAF‐7 pathway genes. We propose that MFB‐1 is a novel F‐box protein that negatively regulates dauer formation in concert with the DAF‐7 signalling pathway inC. elegans.
Internucleosomal DNA cleavage in apoptotic WEHI 231 cells is mediated by a chymotrypsin‐like protease
Authors: Murn Jernej , Urleb Uros , Mlinaric‐Rascan Irena
Published: October 2004

Although several lines of evidence support a role for serine proteases in apoptosis, little is known about the mechanisms involved. In the present study, we have examined the apoptosis‐inducing potential and dissected the death‐signalling pathways of N‐tosyl‐L‐phenylalanine chloromethyl ketone (TPCK) and N‐tosyl‐L‐lysine chloromethyl ketone (TLCK), inhibitors of chymotrypsin‐ and trypsin‐like proteases, respectively. Our results designate two distinct roles for serine proteases. Firstly, we show that both inhibitors induce biochemical and morphological characteristics of apoptosis, including proteolysis of poly(ADP‐ribose) polymerase 1 (PARP‐1) and inhibitor of caspase‐activated DNase (ICAD), as well as mitochondrial dysfunction, and that their action is abrogated by the caspase inhibitor benzyloxycarbonyl‐Val‐Ala‐Asp.fluoromethylketone (z‐VAD.fmk). These results suggest that inhibition of anti‐apoptotic serine proteases governs the onset of the caspase‐dependant apoptotic cascade. Secondly, we also demonstrate the involvement of a serine protease in the terminal stage of apoptosis. We showed that chymotrypsin‐like protease activity is required for internucleosomal DNA fragmentation in apoptotic cells. Hence, DNA fragmentation is abrogated in TPCK‐pre‐treated WEHI 231 cells undergoing apoptosis triggered either by anti‐IgM or TLCK. These results indicate that internucleosomal DNA cleavage in apoptotic cells is mediated by a chymotrypsin‐like protease.
Late relapse of stage I testicular seminoma metastatic to just a para‐ureteropelvic region
Authors: TADOKORO MANABU , MASUDA HITOSHI , FUJII YASUHISA , KOBAYASHI TSUYOSHI , KAGEYAMA YUKIO , KIHARA KAZUNORI
Published: October 2004

A follow‐up ultrasonography study 43 months after an operation for left stage I testicular seminoma in a 39‐year‐old man revealed left hydronephrosis. Serum beta‐human chorionic gonadotropin (β‐hCG) levels were slightly increased. Computed tomography scans of the abdomen showed a bulky tumor around the ureteropelvic region without para‐aortic lymph node enlargement, but did not show a clear distinction between a recurrence of the testicular tumor and an invasive ureteral tumor. After the patient underwent two cycles of chemotherapy with cisplatin and etoposide, the tumor mass decreased by approximately 60% and β‐hCG levels returned to normal. We then performed a resection of the residual tumor involving the upper ureter and left kidney and a retroperitoneal lymph node dissection under a clinical diagnosis of recurrence of the testicular tumor. Histologically, no viable cancer cells remained. The patient has been well with no evidence of recurrence for more than two years.
Intravesical mass consisting of mucosa‐associated lymphoid tissue
Authors: SUZUKI TSUNEKI , MATSUMURA TSUYOSHI , ITO ICHIRO
Published: October 2004

We report on a patient with an intravesical mass consisting of hyperplastic follicles in mucosa‐associated lymphoid tissue. Computed tomography and ultrasonography revealed two intravesical masses measuring 3.5 cm and 1.5 cm along the long axis. Imaging diagnosis was invasive tumors of the bladder. However, the pathological diagnosis on transurethral bladder tumor biopsy was a lesion in lamina propria consisting of hyperplastic follicles and lymphatic infiltrate between them with no cell atypia. Light microscopically, the lesion was considered to be reactive follicular hyperplasia. Antibiotic therapy resulted in an almost complete disappearance of the tumors. Such large follicular hyperplasia in the lamina propria of the bladder is rare.
Evaluation of the impact of natural enemies on Plutella xylostella L. (Lepidoptera: Yponomeutidae) populations on commercial Brassica farms
Authors: Furlong Michael J. , Shi Zu‐hua , Liu Shu‐Sheng , Zalucki Myron P.
Published: October 2004

Abstract  1 Accurate assessment of the impact of natural enemies on pest populations is fundamental to the design of robust integrated pest management programmes. In most situations, diseases, predators and parasitoids act contemporaneously on insect pest populations and the impact of individual natural enemies, or specific groups of natural enemies, is difficult to interpret. These problems are exacerbated in agro‐ecosystems that are frequently disrupted by the application of insecticides.

2 A combination of life‐table and natural enemy exclusion techniques was utilized to develop a method for the assessment of the impact of endemic natural enemies on Plutella xylostella populations on commercial Brassica farms.

3 At two of the experimental sites, natural enemies had no impact on P. xylostella survival, at two other sites, natural enemy impact was low but, at a fifth site, natural enemies drastically reduced the P. xylostella population.

4 The calculation of marginal death rates and associated k‐values allowed the comparison of mortality factors between experimental sites, and indicated that larval disappearance was consistently the most important mortality factor, followed by egg disappearance, larval parasitism and pupal parasitism. The appropriateness of the methods and assumptions made to calculate the marginal death rates are discussed.

5 The technique represents a robust and easily repeatable method for the analysis of the activity of natural enemies of P. xylostella, which could be adapted for the study of other phytophagous pests.
Host plant preference and performance of the vine weevil Otiorhynchus sulcatus
Authors: Van Tol R. W. H. M. , Van Dijk N. , Sabelis M. W.
Published: October 2004

Abstract  1 The relationship between reproductive performance and preference for potential host plants of the vine weevil is investigated, as shown in tests on contact (or feeding) preference, presented herein, and tests on olfactory preference, published elsewhere.

2 Assessment of reproductive performance shows that the host‐plant range of the adult vine weevil Otiorhynchus sulcatus in Europe is limited to one gymnosperm genus (Taxus sp.) and a broad range of angiosperm plants in two subclasses of the Dicotyledonae, namely Dilleniidae and Rosidae. The successful reproduction on very distantly related plant taxa suggests that the original weevil‐ and plant‐habitat has mediated the current host‐plant range of the vine weevil.

3 Contact‐preference tests with equally suitable hosts, such as Aronia, Fragaria, Euonymus and Taxus, and one less suitable host, Humulus, indicate a mismatch between contact preference and performance and, as far as olfactory preferences are known, these match neither the contact preferences nor the performance. This mismatch may arise because (i) host plant species offered do not occur in weevil habitat in Europe (e.g. Aronia and the cultivated Fragaria come from North America) and (ii) predation (or disease) risks differ among host plants, thereby altering effective reproductive performance.

4 With respect to performance on novel hosts (Thuja, Prunus) and bad hosts (Rhododendron), some between‐individual variation is found within a single population, suggesting that local populations harbour (possibly genetic) variation for adaptation to new hosts. How this variation is maintained in the face of strong selection pressures on local populations of flightless and thelytokous weevils, is an important question for understanding the broad host plant range in the vine weevil.
INEQUALITY, REDISTRIBUTION, AND RENT‐SEEKING
Authors: Rodríguez Francisco
Published: October 2004

This paper presents a non‐median voter model of redistribution in which greater inequality leads to lower redistribution. Bargaining between interest groups and politicians over exemptions implies that individuals with sufficiently high income will not pay taxes in equilibrium. Therefore, voters will set tax rates low enough so as to control the incentives for rent‐seeking. An increase in inequality, by putting more income in the hands of individuals that can buy exemptions, will lead to lower equilibrium redistribution. The model can be used to account for a negative relationship between inequality and growth and provides a new explanation of why the poor do not expropriate the rich in democracies.
Conserved expression domains for genes upstream and within the HoxA and HoxD clusters suggests a long‐range enhancer existed before cluster duplication
Authors: Lehoczky Jessica A. , Williams Melissa E. , Innis Jeffrey W.
Published: October 2004

Summary
The posterior HoxA and HoxD genes are essential in appendicular development. Studies have demonstrated that a “distal limb enhancer,” remotely located upstream of the HoxD complex, is required to drive embryonic autopod expression of the posterior Hox genes as well as the two additional non‐Hox genes in the region: Evx2 and Lnp. Our work demonstrates a similar mode of regulation for Hoxa13 and four upstream genes: Evx1, Hibadh, Tax1bp, and Jaz1. These genes all show embryonic (E11.5–E13.5) distal limb and genital bud expression, suggesting the existence of a nearby enhancer influencing the expression of a domain of genes. Comparative sequence analysis between homologous human and mouse genomic sequence upstream of Hoxa13 revealed a remote 2.25‐kb conserved noncoding sequence (mmA13CNS) within the fourth intron of the Hibadh gene. mmA13CNS shares a common 131‐bp core identity within a conserved noncoding sequence upstream of Hoxd13, which is located within the previously identified distal limb enhancer critical region. To test the function of this conserved sequence, we created mmA13CNS‐Hsp86‐lacZ transgenic mice. mmA13CNS directed a wide range of tissue expression, including the central nervous system, developing olfactory tissue, limb, and genital bud. Limb and genital bud expression directed by mmA13CNS is not identical to the patterns exhibited by Hoxa13/Evx1/Hibadh/Tax1bp1/Jaz1, suggesting that mmA13CNS is not sufficient to fully recapitulate their expression in those tissues. The Evx1‐ and Evx2‐like central nervous system expression observed in these mice suggests that the long‐range regulatory element(s) for the Hox cluster existed before the cluster duplication.
On the Structure of Tetralead(II) Complexes with OH Bridges
Authors: Breza Martin , Biskupič Stanislav
Published: October 2004

Using Hartree-Fock, B3LYP and MP2 treatments, the optimal geometries and corresponding electronic structures of tetrahedral [Pb4(μ3-OH)n]q and [Pb4O(μ3-OH)n]q-2 complex cations with total charges q = 8 - n , n = 2, 3, 4, are investigated. After OH- removal, the central oxygen atom in [Pb4O(μ3-OH)4]2+ is shifted to the apical position in [Pb4O(μ3-OH)3]3+ whereas the [Pb4(μ3-OH)2]6+ and [Pb4O(μ3-OH)2]4+ complex cations are unstable. Direct Pb-Pb and O-O interactions are weakly antibonding in all the systems under study. The clusters are held together exclusively by relatively weak Pb-O bonds. A higher stability of the complex cations with a larger number of OH- bridges may be confirmed.
Derivatives of (Phenylsulfanyl)benzoic Acids with Multiple Antileukotrienic Activity
Authors: Kuchař Miroslav , Kmoníček Vojtěch , Panajotová Vladimíra , Jandera Antonín , Brunová Bohumila , Junek Richard , Bucharová Věra , Čejka Jan , Šatinský Dalibor
Published: October 2004

A series of derivatives of (phenylsulfanyl)benzoic acids bearing quinoline, 2,4-dihydroxy-3-propylacetophenone and 2,4-difluorobiphenyl moieties were prepared and their antileukotrienic activities evaluated. Some of the compounds were found to display multiple antileukotrienic effect in the inhibition of LTB4biosynthesis, binding to LTD4and LTB4receptors, superior to the standards (zileuton and zafirlukast) used. The compounds had an antiinflammatory effect, manifested with quinoline derivatives by a significant inhibition of bronchospasm induced by LTD4and/or albumin. The results of regression analysis correspond to the observation that the most active compounds belong to quinoline derivatives with the lowest lipophilicity. X-ray analysis of the quinoline compounds revealed that an intramolecular hydrophobic interaction of their aromatic rings does not occur in the solid state.
Molecular strain identification of theMycobacterium tuberculosiscomplex in archival tissue samples
Authors: Zink A R , Nerlich A G
Published: October 2004

Aims:To investigate the use of different molecular analyses that can identify distinct strains of human pathogenic mycobacteria in formalin fixed and paraffin wax embedded archival tissue samples to see whether it is possible to differentiate between the members of theMycobacterium tuberculosiscomplex (M tuberculosis,M bovis,M africanum,M microti, orM canettii)and/or substrains in a high number of samples. This would be of interest for identifying individual infection traits and superinfection by different mycobacterial strains.

Methods:Forty nine archival tissue samples with clinically and/or histologically suspected tuberculosis infection were subjected to molecular DNA analysis.

Results:The molecular analysis revealed the presence ofM tuberculosiscomplex DNA in 20 samples, whereas acid fast bacilli could be detected by Ziehl-Neelsen staining in only eight samples. All IS6110 positive samples were further characterised by spoligotyping and seven cases providedM tuberculosisspecific signatures, whereasM bovisspecific signatures were obtained in four cases. The analysis of mtp40, oxyR, and pncA partial gene sequences confirmed the presence ofM tuberculosisin six cases andM bovisin one case. The amplification and sequencing of four further genetic regions (katG, gyrA, TbD1, RD9) characterised six “modern”M tuberculosisstrains belonging to genetic groups 2 or 3.

Conclusion:This study provides clear evidence that archival paraffin wax embedded material can be used for further studies on the strain identification ofM tuberculosiscomplex strains and can therefore unequivocally be used for the study of the epidemiology and evolution of tuberculosis pathogens.
ALCAM/CD166 is overexpressed in colorectal carcinoma and correlates with shortened patient survival
Authors: Weichert W , Knösel T , Bellach J , Dietel M , Kristiansen G
Published: October 2004

Background:Activated leucocyte cell adhesion molecule (ALCAM) has been implicated in tumorigenesis and tumour progression of malignant melanoma and prostate cancer.

Aims:To clarify the expression patterns of ALCAM in colon cancer and to correlate these with clinicopathological parameters, including patient survival.

Methods:One hundred and eleven colorectal carcinomas were immunostained for ALCAM (clone MOG/07) using a standard detection system. Cytoplasmic and membranous immunoreactivity were scored semiquantitatively. Fisher’s exact test, χ2test for trends, Kaplan–Meier analysis, and Cox’s regression were applied.

Results:In colorectal cancer, 58.6% and 30.6% of cases showed strong cytoplasmic and membranous expression of ALCAM, respectively. No significant correlation with patient age, tumour grade, stage, or nodal status was apparent. In survival analyses, membranous ALCAM expression correlated significantly (Cox’s regression, p  =  0.028; relative risk, 2.3) with shortened patient survival.

Conclusions:ALCAM is frequently upregulated in colorectal cancer and is a new independent prognostic marker, underscoring the importance of ALCAM in tumour progression in this disease.
Lymphocytic gastritis-like T cell lymphoma: molecular evidence of an unusual recurrence
Authors: Nga M E , Tan S H , Teh M , Koay E S C , Chong S M , Putti T C , Salto-Tellez M
Published: October 2004

This report describes a patient with a gastric biopsy specimen showing histomorphological and immunohistochemical appearances indistinguishable from those usually present in lymphocytic gastritis, a rare condition of unknown aetiology with a distinctive phenotype. The patient had a history of a biopsy confirmed T cell non-Hodgkin lymphoma at two anatomical sites (bladder and stomach), which was subsequently treated. Molecular analysis of the T cell receptor (TCR) γ chain gene rearrangements showed a distinct monoclonal T cell population in the bladder and gastric biopsies. The same analysis in the lymphocytic gastritis-like biopsy sample showed a monoclonal population with identical base pair size to that identified in the other specimens. This report highlights the importance of TCR gene rearrangement analysis in the diagnosis of unusual gastric inflammation, and the use of capillary electrophoresis based polymerase chain reaction in the follow up of lymphoproliferative disorders.
Histopathological assessment of lymph nodes in colorectal carcinoma: does triple levelling detect significantly more metastases?: Figure 1
Authors: Verrill C , Carr N J , Wilkinson-Smith E , Seel E H
Published: October 2004

Aims:Standard practice is to take one section from every lymph node found in colorectal carcinoma resection specimens, to look for metastatic carcinoma. This study evaluates whether assessing three sections separated by 100 μm detects significantly more metastases in nodes than the conventional single section.

Methods:A retrospective study of 100 colorectal carcinoma resection specimens. All blocks containing lymph nodes had two extra histological sections cut (separated by 100 μm) and stained with haematoxylin and eosin. The original slide was called level 1, and the extra two sections levels 2 and 3.

Results:Twenty Dukes’s A (equivalent to WHO-UICC stage grouping I, pTNM stage pT1/2N0), 43 Dukes’s B (equivalent to WHO-UICC stage grouping II, pTNM stage pT3/4N0), and 37 Dukes’s C (equivalent to WHO-UICC stage grouping III, pTNM stage at least pN1) cases were examined (total 1453 nodes). Twelve extra metastases (in 11 patients) were discovered in nodes at levels 2 and 3, which were negative in level 1. Ten cases were Dukes’s C and, in one patient, this led to upstaging from N1 to N2 (pTNM classification system). One case was Dukes’s B and the discovery of a single metastasis on level 2 upstaged it to Dukes’s C.

Conclusions:Triple levelling detected more tumour deposits than the conventional single section. In two patients, the staging classification of the lesion was changed, with potentially important implications for prognosis and management.
PKC-δ-dependent activation of oxidative stress in adipocytes of obese and insulin-resistant mice: role for NADPH oxidase
Authors: Talior Ilana , Tennenbaum Tamar , Kuroki Toshio , Eldar-Finkelman Hagit
Published: October 2004

Oxidative stress is thought to be one of the causative factors contributing to insulin resistance and type 2 diabetes. Previously, we showed that reactive oxygen species (ROS) production is significantly increased in adipocytes from high-fat diet-induced obese and insulin-resistant mice (HF). ROS production was also associated with the increased activity of PKC-δ. In the present studies, we hypothesized that PKC-δ contributes to ROS generation and determined their intracellular source. NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI) reduced ROS levels by 50% in HF adipocytes, and inhibitors of NO synthase (l-NAME, 1 mM), xanthine oxidase (allopurinol, 100 μM), AGE formation (aminoguanidine, 10 μM), or the mitochondrial uncoupler (FCCP, 10 μM) had no effect. Rottlerin, a selective PKC-δ inhibitor, suppressed ROS levels by ∼50%. However, neither GÖ-6976 nor LY-333531, effective inhibitors toward conventional PKC or PKC-β, respectively, significantly altered ROS levels in HF adipocytes. Subsequently, adenoviral-mediated expression of wild-type PKC-δ or its dominant negative mutant (DN-PKC-δ) in HF adipocytes resulted in either a twofold increase in ROS levels or their suppression by 20%, respectively. In addition, both ROS levels and PKC-δ activity were sharply reduced by glucose depletion. Taken together, these results suggest that PKC-δ is responsible for elevated intracellular ROS production in HF adipocytes, and this is mediated by high glucose and NADPH oxidase.
The calcium-sensing receptor: a key factor in the pathogenesis of secondary hyperparathyroidism
Authors: Rodriguez Mariano , Nemeth Edward , Martin David
Published: October 2004

Serum calcium levels are regulated by the action of parathyroid hormone (PTH). Major drivers of PTH hypersecretion and parathyroid cell proliferation are the hypocalcemia and hyperphosphatemia that develop in chronic kidney disease patients with secondary hyperparathyroidism (SHPT) as a result of low calcitriol levels and decreased kidney function. Increased PTH production in response to systemic hypocalcemia is mediated by the calcium-sensing receptor (CaR). Furthermore, as SHPT progresses, reduced expression of CaRs and vitamin D receptors (VDRs) in hyperplastic parathyroid glands may limit the ability of calcium and calcitriol to regulate PTH secretion. Current treatment for SHPT includes the administration of vitamin D sterols and phosphate binders. Treatment with vitamin D is initially effective, but efficacy often wanes with further disease progression. The actions of vitamin D sterols are undermined by reduced expression of VDRs in the parathyroid gland. Furthermore, the calcemic and phosphatemic actions of vitamin D mean that it has the potential to exacerbate abnormal mineral metabolism, resulting in the formation of vascular calcifications. Effective new treatments for SHPT that have a positive impact on mineral metabolism are clearly needed. Recent research shows that drugs that selectively target the CaR, calcimimetics, have the potential to meet these requirements.
Identification of MEF2-regulated genes during muscle differentiation
Authors: Paris James , Virtanen Carl , Lu Zhibin , Takahashi Mark
Published: October 2004

Although a great deal has been elucidated concerning the mechanisms regulating muscle differentiation, little is known about transcription factor-specific gene regulation. Our understanding of the genetic mechanisms regulating cell differentiation is quite limited. Much of what has been defined centers on regulatory signaling cascades and transcription factors. Surprisingly few studies have investigated the association of genes with specific transcription factors. To address these issues, we have utilized a method coupling chromatin immunoprecipitation and CpG microarrays to characterize the genes associated with MEF2 in differentiating C2C12cells. Results demonstrated a defined binding pattern over the course of differentiation. Filtered data demonstrated 9 clones to be elevated at 0 h, 792 at 6 h, 163 by 1 day, and 316 at 3 days. Using unbiased selection parameters, we selected a subset of 291 prospective candidates. Clones were sequenced and filtered for removal of redundancy between clones and for the presence of repetitive elements. We were able to place 50 of these on the mouse genome, and 20 were found to be located near well-annotated genes. From this list, previously undefined associations with MEF2 were discovered. Many of these genes represent proteins involved in neurogenesis, neuromuscular junctions, signaling and metabolism. The remaining clones include many full-length cDNA and represent novel gene targets. The results of this study provides for the first time, a unique look at gene regulation at the level of transcription factor binding in differentiating muscle.
Childhoods Across the Generations
Authors: Brannen Julia
Published: October 2004

This article draws upon new analysis from a qualitative study of four-generation English families. It takes a historical generational perspective and explores perspectives on the childhoods of three generations of women. The article also offers a number of theoretical and methodological reflections upon the interpretation of life stories: the need to make sense of accounts in relation to life course phase; the need to examine the nature of the account being given and the time frames to which different parts of an account refer; the problems in treating accounts as reflections of historical conditions; and the difficulties in contextualizing accounts where context is assumed or ignored.
Between Reality and Representation
Authors: Rajasingham-Senanayake Darini
Published: October 2004

During two decades of armed conflict in north east Sri Lanka, women have carved new spaces of agency and new roles as armed combatants, principal income generators or heads of household in the absence of men folk. Will they be pushed back ‘into the kitchen’ with a return to peace, also often indexed as a return to the pre-war gender status quo? This article focuses on women’s agency in post-conflict Sri Lanka, where a peace process has been ongoing for two years, and asks if and how a return of peace may affect women’s empowerment. Based on ethnographic fieldwork and analysis of the political economy of armed conflict, the article suggests that, contrary to nationalist imaginaries, the structure of the ‘new war’ in Sri Lanka may not permit a return to a pre-war gender status quo.
Adjudicating Pluralism: The Hijab, Law and Social Change in Post-Colonial Trinidad
Authors: Mahabir Cynthia
Published: October 2004

In 1994, fundamentalist Muslim Islamists in the Caribbean island nation of Trinidad and Tobago organized a campaign to institutionalize the wearing of the traditional Muslim headscarf – the hijab – in nonIslamic schools. A lawsuit was brought on behalf of an 11 year old Muslim schoolgirl who had been told that she would not be allowed to wear the hijab while attending the Catholic run but state supported Holy Name Convent school. The ‘ hijab case’, as it came to be known, was framed as a religious matter, but it was essentially a political contest that was played out in court in an unprecedented case in which law was mobilized as a mechanism for cultural change. Drawing on extensive research and participant interviews, this article examines the strengths and limitations revealed in this attempt to use the law as a means of promoting religious pluralism in a complex, multicultural, secular society.
Non-Stationary Responses in Externally Excited Two-Degrees-of-Freedom Nonlinear Systems with 1: 2 Internal Resonance
Authors: Bajaj Anil K. , Davies Patricia , Banerjee Bappaditya
Published: October 2004

The dynamics of two-degrees-of-freedom dynamical systems with weak quadratic nonlinearities is analyzed in the neighborhood of bifurcation points when the excitation frequency varies slowly through the region of primary resonance. The two modes of vibration are in 1: 2 subharmonic internal resonance. The slowly evolving averaged equations are numerically studied for motions initiated in the vicinity of stationary responses, and observations are made about the nature of responses of the system near the transition from single-mode to coupled-mode solutions (pitchfork points), and near jump and Hopf bifurcations in the coupled-mode solutions. An analytical technique based on the dynamic bifurcation theory is developed to explain the numerical observations for passage through the bifurcations. A numerical study is carried out to determine the effects of system parameters on the dynamics near the pitchfork bifurcation points and results are compared with analytical and numerical descriptions of dynamics.
Inhibition of vascular endothelial growth factor receptor 2–mediated endothelial cell activation by Axl tyrosine kinase receptor
Authors: Gallicchio Margherita , Mitola Stefania , Valdembri Donatella , Fantozzi Roberto , Varnum Brian , Avanzi Gian Carlo , Bussolino Federico
Published: October 2004

GAS6, the product of a growth arrest specific (GAS) gene, is the ligand of the tyrosine kinase receptor Axl. GAS6 and Axl are both expressed in endothelial cells, where they are involved in many processes such as leukocyte transmigration through capillaries and neointima formation in injured vessels. Here, we show that Axl stimulation by GAS6 results in inhibition of the ligand-dependent activation of vascular endothelial growth factor (VEGF) receptor 2 and the consequent activation of an angiogenic program in vascular endothelial cells. GAS6 inhibits chemotaxis of endothelial cells stimulated by VEGF-A isoforms, but not that triggered by fibroblast growth factor-2 or hepatocyte growth factor. Furthermore, it inhibits endothelial cell morphogenesis on Matrigel and VEGF-A–dependent vascularization of chick chorion allantoid membrane. GAS6 activates the tyrosine phosphatase SHP-2 (SH2 domain-containing tyrosine phosphatase 2), which is instrumental in the negative feedback exerted by Axl on VEGF-A activities. A dominant-negative SHP-2 mutant, in which Cys 459 is substituted by Ser, reverted the effect of GAS6 on stimulation of VEGF receptor 2 and endothelial chemotaxis triggered by VEGF-A. These studies provide the first demonstration of a cross talk between Axl and VEGF receptor 2 and add new information on the regulation of VEGF-A activities during tissue vascularization.
Peroxynitrite-mediated inactivation of heme oxygenases
Authors: Kinobe Robert , Ji Yanbin , Nakatsu Kanji
Published: October 2004

Background

Endogenous nitric oxide (NO) and carbon monoxide (CO) are generated by nitric oxide synthase and heme oxygenase, respectively. Like NO, CO has been accepted as an important cellular signaling molecule in biological systems. An up-regulation in both gene and protein expression of heme oxygenase-1 (HO-1) under oxidative/nitrosative stress has been well documented, and the protective role of HO-1 and HO-2 against oxidative damage is proposed. However, data on the direct effect of reactive oxygen/nitrogen species (ROS/RNS) on HO function is incomplete. Using gas chromatography to quantify carbon monoxide (CO) formation from heme oxidation, we investigated the effects of peroxynitrite (ONOO-) on the in vitro catalytic activity of rat spleen (HO-1) and brain (HO-2) microsomal heme oxygenases.

Results

Exposure to ONOO- led to concentration-dependent but reversible decreases in the activity of microsomal rat spleen and brain HO activity. Spleen HO activity was 100-fold more sensitive to ONOO--dependent inactivation compared to that of the brain, with IC50 values of 0.015 ± 0.005 mM and 1.25 ± 0.25 mM respectively. Inhibition of both rat spleen and brain microsomal HO activity was also observed with tetra-nitromethane, a tyrosine nitrating agent, as well as two NO donors, S-nitrosoglutathione (GSNO) and diethylamine NONOate (DEA-NONOate). However, no additive effect was found following the application of NO donors and ONOO- together.

Conclusion

These results indicate that ONOO- may regulate HO-1 and HO-2 activities by mechanisms that involve different interactions with these proteins. It is suggested that while nitration of tyrosine residues and oxidation of sulfhydryl groups may be involved, consideration should be given to other facets of ONOO- chemistry. This inhibition of HO activity offers a mechanism for cross talk between the nitric oxide synthase and HO systems.
Readmission and overstay after day case nasal surgery
Authors: Singh Gurminder , McCormack David , Roberts David R
Published: October 2004

Background

A readmission is classified as a patient necessitating readmission to hospital due to a post-operative complication following discharge. An overstay however, is classified as a patient having to stay longer than the planned duration in hospital (not having been discharged in the interim) due to a post-operative complication. This study aims to investigate patient-related factors that predispose to readmission or overstay and thus make recommendations to decrease the likelihood of readmission or overstay.

Method

In this retrospective study 312 'day-case nasal procedures', were selected from a total cohort of 4274 ENT patients over a 17-month period. This sub-group was investigated for a range of demographic factors including, age, gender and ethnicity with regards to their relationship to readmission rates and overstay frequency and duration.

Results

The rates were 2.88% and 9.62% for readmission and overstay respectively. The total number of days spent in hospital as a result of readmission was 27. Epistaxis was the leading cause for readmission/overstay (28.9%) followed by high levels of post-operative pain preventing them from being discharged (23.7%). All procedures in this study had readmission rates that were below those recommended in the guidelines set by the Royal College of Surgeons of England. Women overstayed significantly longer (t = 1.65, p < 0.05) than men.

Conclusions

Suitable candidates for day-case ENT surgery highlighted by this study include healthy individuals between the ages of 20 and 60. Operating in the morning would increase the immediate post-operative recovery time, which may reduce the numbers of patients who complain of high levels of pain at the time of discharge. Procedures such as septorhinoplasty being performed routinely in the ambulatory setting require additional research into more effective methods of pain control. Standards need to be improved so that the causes of overstay and readmission are clearly identifiable in patient records.
Translocation of theDictyosteliumTRAP1 homologue to mitochondria induces a novel prestarvation response
Authors: Morita Tsuyoshi , Amagai Aiko , Maeda Yasuo
Published: October 2004

Dd-TRAP1 is a Dictyostelium homologue of tumor necrosis factor receptor-associated protein 1 (TRAP-1). Dd-TRAP1 is located in the cortex of cells growing at a low density, but was found to be translocated to mitochondria with the help of a novel prestarvation factor that was accumulated in growth medium along with increased cell densities. The knockdown mutant of Dd-TRAP1 (TRAP1-RNAi cells) exhibited a significant defect in prestarvation response. Although TRAP1-RNAi cells showed normal expressions of classical prestarvation genes [dscA (discoidin I) and car1 (carA; cAMP receptor)], the expression of differentiation-associated genes (dia1 and dia3) induced by the prestarvation response were markedly repressed. By contrast, transformants overexpressing Dd-TRAP1 showed an early prestarvation response and also increased expression of dia1 and dia3 in a cell-density-dependent manner. Importantly, introduction of Dd-TRAP1 antibody into D. discoideum Ax-2 cells by electroporation inhibited the translocation of Dd-TRAP1 from the cortex to mitochondria and greatly inhibited the initiation of differentiation. Taken together, these results indicate that Dd-TRAP1 is translocated to mitochondria by sensing the cell density in growth medium and enhances the early developmental program through a novel prestarvation response.
Population Pharmacokinetics III: Design, Analysis, and Application of Population Pharmacokinetic Studies
Authors: Ette Ene I , Williams Paul J , Lane James R
Published: October 2004

OBJECTIVE

To present a framework within which population pharmacokinetic (PPK) studies should be designed and analyzed and discuss the application of developed PPK models.

METHODS

Information on PPK was retrieved from a MEDLINE search (1979–December 2003) of the literature and a bibliographic evaluation of review articles and books. This information is used in conjunction with experience to explain the design and analysis of PPK studies. Also, examples are included to demonstrate the usefulness of PPK.

SYNTHESIS

A great deal of thought must be given to the design and analysis of PPK studies (ie, development of PPK models). Models are of 2 primary types—descriptive and predictive—and the process applied to these models is necessarily different. An approach that ensures model applicability is presented.

CONCLUSIONS

PPK models have great utility, and the applications are many. They are very different from single-subject pharmacokinetic models and therefore require different approaches to model estimation.
Localization and temporal regulation of tissue inhibitors of metalloproteinases 3 and 4 in bovine preovulatory follicles
Authors: Li Qinglei , Bakke Leanne J , Pursley J Richard , Smith George W
Published: October 2004

The matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are potential regulators of the focalized extracellular matrix degradation required for ovulation. The objectives of the present study were to determine localization and temporal regulation of TIMP-3 and TIMP-4 mRNA and protein in bovine preovulatory follicles. Ovaries containing preovulatory follicles were collected at 0, 12 and 20 h after GnRH injection for real-time PCR quantification of TIMP-3 and TIMP-4 mRNAs and immunohistochemical localization studies. Additional samples collected at 0, 6, 12, 18 and 24 h post GnRH injection were subjected to Western analysis to determine temporal changes in TIMP-3 and TIMP-4 proteins in the apex and base of preovulatory follicles. Results indicate the gonadotropin surge regulates TIMP-3 and TIMP-4 expression. TIMP-3 and TIMP-4 mRNAs increased within 12 h after GnRH injection. TIMP-3 protein was localized to granulosal and thecal layers of preovulatory follicles and adjacent ovarian stroma, whereas TIMP-4 immunoreactivity was localized to granulosal and thecal cells and ovarian blood vessels. Amounts of TIMP-3 and TIMP-4 proteins in the follicular apex peaked within 12 h post GnRH injection and subsequently declined by 24 h. However, amounts of TIMP-3 and TIMP-4 proteins in the base were not elevated after GnRH administration. Results demonstrate that mRNA and protein for both TIMP-3 and TIMP-4 are increased in bovine preovulatory follicles following the gonadotropin surge. Coordinate expression of TIMPs and MMPs may help regulate the extracellular matrix remodeling characteristic of the ovulatory process.
Cellular localization and changes in expression of prolactin receptor isoforms in sheep ovary throughout the estrous cycle
Authors: Picazo R A , García Ruiz J P , Santiago Moreno J , González de Bulnes A , Muñoz J , Silván G , Lorenzo P L , Illera J C
Published: October 2004

The actions of prolactin (PRL) on target cells depend on the type of prolactin receptor (PRLr) predominantly expressed, particularly whether the long PRLr isoform is expressed. The aims of this study were to determine the cellular localization and the changes in expression of long and short PRLr isoforms in sheep ovary throughout the estrous cycle. Long and short PRLrs were localized mostly in the same ovarian cells. Maximum signal intensity, particularly for long PRLrs, was found in stromal cells surrounding primordial and primary follicles, and, for both PRLrs, in granulosa cells of preantral follicles and in luteal cells. Moderate signal intensity for PRLrs was found in theca cells of preantral to ovulatory follicles, and in granulosa cells of antral follicles up to the gonadotropin-dependent stage. Decreasing immunoreactivity to PRLrs was found in granulosa cells of gonadotropin-dependent to ovulatory follicles. For long PRLrs in particular, no signal was found in mural granulosa cells of gonadotropin-dependent follicles; for both isoforms, no signal was found in most granulosa cells of ovulatory follicles. In primordial to gonadotropin-dependent follicles, cellular localization of PRLr was similar on days 0, 10 and 15 of the cycle. Oocytes consistently showed positive immunostaining for PRLrs. Comparative RT-PCR analysis of long and short PRLr expression showed that the short isoform is evenly expressed throughout the estrous cycle, whereas the expression of the long form increases at the time of estrus and decreases at mid-luteal phase and at the onset of the follicular phase. Expression of long PRLrs was greater than that of short PRLrs on day 0 of cycle; expression of both isoforms was similar on day 10 and on day 15, long PRLrs expression was lower than that of short PRLrs. Our results indicate that in sheep ovary, the maximum responsiveness to PRL might occur during the preovulatory phase of the estrous cycle.
Aggregate States and Energetic Disorder in Highly Ordered Nanostructures ofpara‐Sexiphenyl Grown by Hot Wall Epitaxy
Authors: Kadashchuk A. , Andreev A. , Sitter H. , Sariciftci N. S. , Skryshevski Y. , Piryatinski Y. , Blonsky I. , Meissner D.
Published: October 2004

We report on photoluminescence (PL) and thermally stimulated luminescence (TSL) in highly ordered nanostructures ofpara‐sexiphenyl (PSP) grown by hot wall epitaxy (HWE). A low‐energy broad band is observed in the PL spectra that can be attributed to the emission from molecular aggregates. While the intrinsic exciton emission in steady‐state PL dominates at low temperatures, the emission from aggregates increases with elevating temperature and its magnitude depends sensitively on film preparation conditions. Time‐resolved PL measurements showed that the aggregate emission decays with a life‐time of ≈ 4 ns, which is approximately an order of magnitude larger than the lifetime of singlet excitons. TSL data suggests the presence of an energetically disordered distribution of localized states for charge carriers in PSP films, which results from an intrinsic disorder in this material. A low‐temperature TSL peak with the maximum at around 30 K evidences for a weak energy disorder in PSP films, and has been interpreted in terms of a hopping model of TSL in disordered organic materials.
Obtaining Characteristic 4f–4f Luminescence from Rare Earth Organic Chelates
Authors: Thompson J. , Blyth R. I. R. , Gigli G. , Cingolani R.
Published: October 2004

We report a study of a series of heavy rare earth tris‐8‐hydroxyquinolines (REQ3s), using UV‐visible absorption spectroscopy, infrared absorption spectroscopy, and photoluminescence (PL) measurements. We show that the heavy REQ3s are all chemically similar to each other and to aluminium tris‐8‐hydroxyquinoline, at least in terms of the ligand behavior. Characteristic rare earth 4f–4f luminescence is only observed for ErQ3 and YbQ3 due to the relatively low energy of the ligand triplet state. We show that a triplet transfer mechanism cannot be responsible for the observed Yb 4f–4f luminescence observed in YbQ3. Instead, an internal chemiluminescent process is shown to be energetically favorable. The thin film PL spectra of all the heavy REQ3s are dominated by triplet emission, except for that of ErQ3, for which transfer to the Er3+ ion represents an efficient alternative. The PL spectra of powder samples, which would be expected to consist of approximately equal amounts of both isomers, are dominated by singlet emission. This is in contrast to the results from the thin films, and suggests that the isomer which predominates in the thin films has a much higher intersystem crossing rate than the other isomer.
Macroporous Zeolitic Membrane Bioreactors
Authors: Wang Y. , Caruso F.
Published: October 2004

A simple and effective method is described for the fabrication of robust zeolitic membranes with three‐dimensional (3D) interconnected macroporous structures. The membranes were prepared by electrostatically seeding mesoporous silica sphere (MSS) self‐assembled films with silicalite‐1 nanoparticles, followed by hydrothermal treatment. The membrane thickness, which is determined by the MSS film thickness, can be easily adjusted from tens to hundreds of micrometers by varying the concentration of the MSS dispersion and the solution volume. Biomacromolecule‐functionalized macroporous zeolitic membrane bioreactors were subsequently prepared via the layer‐by‐layer (LbL) electrostatic assembly of polyelectrolytes and enzyme (catalase) on the 3D macroporous membranes. The enzyme‐modified membranes with interconnected macroporous structures display enzyme loading amounts and activities that are one order of magnitude higher than corresponding 3D zeolite films with closed macropores, and approximately three orders of magnitude higher than their non‐porous planar film counterparts assembled on silica substrates. The enzyme loadings and activities were found to be approximately linearly dependent on the thicknesses of the membranes. Furthermore, the immobilized enzyme exhibits enhanced reaction stability in comparison with enzyme in bulk solution. These membranes are potentially useful for separations as they could be used to simultaneously perform reaction and separation steps.
Semiconducting and Piezoelectric Oxide Nanostructures Induced by Polar Surfaces
Authors: Wang Z. L. , Kong X. Y. , Ding Y. , Gao P. , Hughes W. L. , Yang R. , Zhang Y.
Published: October 2004

Zinc oxide, an important semiconducting and piezoelectric material, has three key characteristics. First, it is a semiconductor, with a direct bandgap of 3.37 eV and a large excitation binding energy (60 meV), and exhibits near‐UV emission and transparent conductivity. Secondly, due to its non‐centrosymmetric symmetry, it is piezoelectric, which is a key phenomenon in building electro‐mechanical coupled sensors and transducers. Finally, ZnO is bio‐safe and bio‐compatible, and can be used for biomedical applications without coating. With these unique advantages, ZnO is one of the most important nanomaterials for integration with microsystems and biotechnology. Structurally, due to the three types of fastest growth directions—<0001>, <01$ \bar 1 $0>, and <2$ \bar 1 $$ \bar 1 $0>—as well as the ±(0001) polar surfaces, a diverse group of ZnO nanostructures have been grown in our laboratory. These include nanocombs, nanosaws, nanosprings, nanorings, nanobows, and nanopropellers. This article reviews our recent progress in the synthesis and characterization of polar‐surface‐induced ZnO nanostructures, their growth mechanisms, and possible applications as sensors, transducers, and resonators. It is suggested that ZnO could be the next most important nanomaterial after carbon nanotubes.