bluuebunny/crossref_metadata_2025 huggingface dataset:
Complete Inhibition of Goiter in Mice Requires Combined Gene Therapy Modification of Angiopoietin, Vascular Endothelial Growth Factor, and Fibroblast Growth Factor Signaling
Authors: Ramsden James D. , Buchanan Malcolm A. , Egginton Stuart , Watkinson John C. , Mautner Vivien , Eggo Margaret C.
Published: April 2005

In goiter, increased expression of growth factors and their receptors occurs. We have inhibited the action of some of these growth factors, alone and in combination, to determine which are important in goitrogenesis. Recombinant adenovirus vectors (RAds) expressing truncated, secreted forms of human Tie2 (RAd-sTie2) and vascular endothelial growth factor receptor 1 (RAd-sVEGFR1) or a truncated, dominant-negative fibroblast growth factor receptor 1 (RAdDN-FGFR1) were used. Goiters in mice were induced by feeding an iodide-deficient diet, containing methimazole and sodium perchlorate. RAds were administered to mice simultaneously with the goitrogenic regimen, which was continued for 14 d. RAd treatment did not significantly affect increases in TSH or reductions in thyroid hormone or thyroid hyperactivity seen in goitrogen-treated controls mice, suggesting no effect on pituitary or thyroid responses to hypothyroidism. In control goiters, a 4-fold increase in vascular volume accompanied a 2-fold increase in thyroid mass. Complete inhibition of these increases was found when animals were treated with the three RAds in combination. In thyroids from three RAd-treated animals, there was marked, significant inhibition of Tie2, FGFR1, VEGFR1, FGF-2, and VEGF expression, compared with control goiters. When used individually, RAdDN-FGFR1 partially prevented goiter and RAd-sVEGFR1 partially reduced vascular volume. Their effects were not additive. RAd-sTie2 did not reduce goiter mass or vascular volume when used alone but was essential for complete goiter inhibition. VEGF and VEGFR1 expression was reduced in these thyroids. Limitation of physiologic organ growth is complex, requiring inhibition of multiple, interdependent growth factor axes.
Electroanalytical Chemistry with Carbon Film Electrodes and Micro and Nano-Structured Carbon Film-Based Electrodes
Authors: Niwa Osamu
Published: April 2005

The recent development of electroanalysis using carbon film electrodes and micro and nano-structured carbon film based electrodes is reviewed. Graphite-like carbon film was synthesized by various methods such as thermal chemical vapor deposition and the thermolysis of organic polymers. Highly stable diamond film electrodes with a wide potential window have been synthesized by using the plasma CVD process and then employed for electroanalysis. A carbon film consisting of electron cyclotron resonance (ECR) sputter-deposited carbon films containing a large portion of sp3 bonds was introduced. The film makes it possible to detect analytes with higher oxidation potential or electroactive species that foul the electrode surface after oxidation. ECR carbon film can be deposited at low temperature and is conductive without doping. Graphite-like carbon films have been formed in order to construct various microelectrodes and microarray electrodes by using photolithography and dry etching methods to meet the requirements for improving the detection limit and for miniaturizing electrochemical detectors for small volume samples. For example, carbon film fabricated into an interdigitated array (IDA) electrode has a very low detection limit for biochemicals such as catecholamines when used as an electrochemical detector for high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE). In contrast, composite carbon films containing various metal nanoparticles can be used for many analytes, including hydrogen peroxide and sugars. The films are deposited by the RF co-sputtering of metal and carbon. This is unlike other preparation methods such as the thermolysis of a polymer–metal complex or the electroplating of metal particles onto carbon film. The obtained carbon film contains 2–5 nm metal particles such as Pt, Ni, Cu, and Ir. The highly sensitive and extremely stable detection of hydrogen peroxide, which is known to be the product of various oxidase enzymatic reactions, was achieved with sputter-deposited carbon film in which Pt nano-particles were dispersed. In contrast, carbon films containing dispersed Ni and Cu nanoparticles provide a high electrocatalytic current for sugars such as glucose and lactose in alkaline solution. By using the film as a detection electrode for HPLC, one can obtain a lower detection limit for several sugars than when using bulk metal electrodes.
Growth of AOT Reversed Micelles and the Solvent Effect Investigated by Dielectric and Light-Scattering Measurements
Authors: Tanaka Reiji , Yokoyama Takuya , Sameshima Kaori , Kawase Tokuzo
Published: April 2005

The relative permittivity (εr) and the conductivity (κ) at a frequency (f) of 50 kHz, and the dynamic light-scattering were measured for ternary systems of (AOT + r·H2O) solved in cyclohexane, heptane, octane, decane, and dodecane at a temperature of 298.15 K as a function of the amount ratio (r) of water to AOT (r = [H2O]/[AOT]) up to the onset of percolation. The molality (m) of AOT for those solutions was 0.15 mol kg−1, and increased to 0.30 mol kg−1 for solutions with dodecane. By increasing r, spherical reversed micelles were formed at r ≈ 6 in straight-chain hydrocarbons. The light-scattering measurements indicated that the mean hydrodynamic diameter of the micelles increased with increasing r, showing a sigmoid curve. The growth of micelles was promoted in a longer chain hydrocarbon. The percolation transition occurred as the particles grew to a critical diameter of about 50 nm. On the other hand, the growth of particles in c-hexane was moderate, and percolation did not occur up to r = 90, where the solution turned turbid. The growth of particles found from light-scattering measurements was well correlated to dielectric observations.
Syntheses, Crystal Structures of Mo–S Clusters [Mo3S4(dtp)3(L)]2[μ-OOC(CH2)nCOO-μ] (L = dmf, dmso; n = 3, 4) and Their Supramolecular Architectures
Authors: Tang Yan-Hong , Qin Ye-Yan , Li Zhao-Ji , Zhang Jian , Kang Yao , Hu Rui-Feng , Wen Yi-Hang , Cheng Jian-Kai , Yao Yuan-Gen
Published: April 2005

The substitution reaction of [Mo3S4(dtp)3(ClCH2COO)(py)] (dtp = diethyl dithiophosphate) or [Mo3S4(dtp)4(H2O)] with adipic acid or glutaric acid in N,N′-dimethylformamide (dmf) or dimethyl sulfoxide (dmso) dimerized two discrete Mo3S4 clusters into novel Mo(IV) cluster compounds [Mo3S4(dtp)3(L)]2[μ-OOC(CH2)nCOO-μ] (L = dmf, n = 4 for 1, n = 3 for 2; L = dmso, n = 3 for 3). Their structures have been determined by X-ray crystallography and spectroscopically characterized. Each molecule of these clusters consists of two incomplete cubane-type [Mo3S4(dtp)3(L)] units, and each unit is respectively coordinated to one dicarboxylate group of the same dicarboxylic acid. Intermolecular S···S and C–H···S contacts, observed in the crystal packing diagram, establish three infinite two-dimensional supramolecular architectures.
Incorporation of Ethylenediamine as a Bi-layer in the Interlayer Space of Tetratitanic Acid by Re-stacking Exfoliated Nanosheets
Authors: Sugimoto Wataru , Ohuchi Kazunori , Murakami Yasushi , Takasu Yoshio
Published: April 2005

The reaction of ethylenediamine with a colloidal suspension containing exfoliated H2Ti4O9 nanosheets was studied. Characterization of the product by X-ray diffraction, thermogravimetry-differential thermal analysis, elemental analysis, and solid-state 13C NMR revealed that two types of ethylenediamine–H2Ti4O9 intercalation compounds, namely, compounds with ethylenediamine in a mono-layer or a bi-layer arrangement, could be prepared depending on the synthetic conditions. The latter composite material is a novel intercalation compound with the ethylenediamine arranged in a bi-layer with one amine group attached to the interlayer surface of H2Ti4O9 as an ammonium cation (–NH3+) and the other group present in the interlayer space in a neutral state (–NH2).
Association of trans-[PdCl2(NH=CPh2-κN)2] via Intermolecular N–H···Cl Hydrogen Bonding in the Solid State and in Solution
Authors: Kuwabara Junpei , Takeuchi Daisuke , Osakada Kohtaro
Published: April 2005

The crystal structure of a new complex, trans-[PdCl2(NH=CPh2-κN)2], shows an association of the two molecules via intermolecular N–H···Cl hydrogen bonds. The 1H NMR signal of the N–H hydrogen in CDCl3 changes its position depending on the concentration and temperature of the solution.
Stereoselective Synthesis of 19-Hydroxytaxoid by Utilizing Samarium(II) Iodide-Mediated Double Aldol Cyclization
Authors: Ogawa Yasuyuki , Kuroda Kiichi , Matsuo Jun-ichi , Mukaiyama Teruaki
Published: April 2005

The stereoselective synthesis of new 19-hydroxytaxoid 36, possessing a double-aldol skeleton was achieved by way of B to BC to ABC ring construction. Optically active 8-membered ring 6 corresponding to the B-ring of 19-hydroxytaxol has been synthesized in high yield from epoxyketo aldehyde 8 by intramolecular samarium(II) iodide-mediated double aldol cyclization. The bicyclic compound 5 corresponding to the BC ring system was prepared from the 8-membered ring 6 by successive trimethylaluminium-assisted stereoselective conjugated addition and intramolecular samarium(II) iodide-mediated double aldol cyclization. The ABC-ring system 4 was constructed by stereoselective homoallylation and pinacol coupling cyclization with low-valent titanium. The synthesis of new 19-hydroxytaxoid 36 was accomplished from ABC ring system 4 by olefination of vicinal diol unit.
Generation of Superoxide in a Water-Soluble Model System with FeTMPyP
Authors: Nakano Taku , Ohto Kanae , Okafuji Fumito , Mori Yoshihiro , Kakuda Hiroko , Hatanaka Yasumaru , Masuoka Noriyoshi
Published: April 2005

In a model system of a water-soluble hemin, tetrakis(4-methylpyridyl)porphinatoiron(III) pentachloride (FeTMPyPCl5), with 3-methyl-2-benzothiazolinone hydrazone (MBTH), superoxide anion radical (O2•−), hydrogen peroxide, and then hydroxyl radical were generated in a phosphate buffer solution (pH 6.0–7.5) under aerobic conditions. The hemin was degraded in this system. The reactive oxygen species were deduced from inhibition of the degradation by adding SOD and catalase, and one of them was trapped by 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a DMPO–hydroxyl radical adduct, which was detected by ESR. The mechanism for activating dioxygen and the degradation of hemin was examined, and it was proposed to be the initial one-electron reduction of hemin by MBTH forming a dioxygen complex and liberating superoxide as one of the routes during the reduction–autoxidation cycle in aqueous media.
Optically Active Seleninic Acid: Isolation, Absolute Configuration, Stability, and Chiral Crystallization
Authors: Nakashima Yusuke , Shimizu Toshio , Hirabayashi Kazunori , Yasui Masanori , Nakazato Masaki , Iwasaki Fujiko , Kamigata Nobumasa
Published: April 2005

Each optical isomer of methaneseleninic acid (1a) was isolated as chiral crystals by recrystallization from methanol/toluene. The absolute configuration of one of the enantiomers was determined by X-ray crystallographic analysis, and the relationship between the absolute configuration and the circular dichroism spectra of 1a was clarified. The optically active seleninic acid (R)-1a was stable toward racemization in the solid state, although it racemized very rapidly in solution. Each enantiomer of 1a was obtained in bulk by chiral crystallization in the presence of a seed crystal or chiral solvents. The absolute configuration of optically active methanesulfinic acid (4) was also assigned by comparing its circular dichroism spectra with those of 1a.
Intermolecular Communication on Lipid Bilayer Membrane. Tuning of Enzymatic Activity with Phase Transition of the Matrix Membranes
Authors: Tian Wen-Jie , Sasaki Yoshihiro , Fan Sheng-Di , Kikuchi Jun-ichi
Published: April 2005

A molecular device, in which the catalytic activity of lactate dehydrogenase was controlled by a response of ditopic molecular recognition of a lipid signal, was constructed on lipid bilayer membranes. The enzymatic activity was tuned up sensitively through phase transition of the matrix membrane as a platform for the intermolecular communication.
Novel Low-Molecular-Weight Gelators Based on Azobenzene Containing l-Amino Acids
Authors: Inoue Daisaku , Suzuki Masahiro , Shirai Hirofusa , Hanabusa Kenji
Published: April 2005

A series of azobenzene derivatives containing glycine, l-alanine, l-valine, l-leucine, and l-isoleucine were synthesized and their gelation properties were examined. Although the azobenzene derivatives containing glycine, l-alanine, and l-leucine exhibited very low gelation abilities, other compounds of l-isoleucine and l-valine acted as good gelators that formed organogels in many organic solvents and oils at relatively low concentrations. The electron microscopic observation demonstrated that a three-dimensional network was created by entanglement of self-assembled nanofibers. Furthermore, the spectroscopic studies suggested that the gelator molecules self-assembled into the nanofibers through hydrogen bonding and π–π interactions, including the H-aggregation mode of the azobenzene segments.
Analysis of Minor Hemoglobins by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry
Authors: Zurbriggen Karin , Schmugge Markus , Schmid Marlis , Durka Silke , Kleinert Peter , Kuster Thomas , Heizmann Claus W , Troxler Heinz
Published: April 2005

Background: Hemoglobin (Hb) heterogeneity arises mainly from posttranslational modifications of the globin chains, and cation-exchange chromatography reveals falsely increased concentrations of some minor Hbs in the presence of abnormal Hbs. Here we describe a method for identification of the globin chains and their posttranslational modifications contained in the Hb fractions.

Methods: We used cation-exchange HPLC (PolyCAT A column) for separation of Hb fractions and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for analysis of the separated globin chains. Globin chains were identified by their molecular masses. Posttranslational modifications of globin chains were identified by digestion of the proteins with endoproteinase V8 before MALDI-TOF MS of the resulting peptides.

Results: Analysis of the HbA2 fractions of patients with HbS revealed 4 different globin chains. We found, in addition to the expected α- and δ-chains, the carbamylated α- and the βS-chains. Additionally, we analyzed HbH, Hb Barts, HbA1b, pre-HbA1c, HbA1c, HbF1, HbF, HbA1d3a, HbA1d3b, HbA2, and HbC1 fractions from control and pathologic blood samples. We identified several posttranslational modifications of the globin chains, such as pyruvatization, glycation, acetylation, carbamylation, and acetaldehyde adduct formation.

Conclusions: The native and posttranslationally modified globin chains in minor and major Hbs are unambiguously identified by MALDI-TOF MS. A minor Hb containing the carbamylated α- and the βS-chain elutes at the same time as normal HbA2 (α2δ2) and thus leads to falsely increased HbA2 values in patients with HbS when blood is analyzed with PolyCAT A chromatography.
Developing Science in Developing Countries: The Harvard College Observatory and the Establishment of Modern Astrophysics in Mexico
Authors: Bartolucci Jorge
Published: April 2005

The 1942 creation of the National Astrophysical Observatory of Tonantzintla, Puebla, marked the beginning of the later establishment of modern astrophysics in Mexico. This advancement was made possible through the support given by the Harvard College Observatory to a group of young Mexican scientists who worked very hard to integrate their country into the international scientific community. Despite the efforts made by Mexican politicians and astronomers before 1940 to build scientific institutions to promote the progress of science in the country, public and private support was sporadic, fragmented, weak and directionless. What happened in the 1940s that made it possible to overcome these obstacles? According to this analysis, success can be explained as a consequence of the close interaction between Harlow Shapley and Luis E. Erro under very singular historical circumstances. Since their collaboration took place within the context of the Second World War, the influence of geopolitical affairs must be underlined. As a case study, the essay highlights the presence of social and historical factors that particularized the process of more globalized transference of modern science outside Western Europe and the United States.

El establecimiento de la astronomía moderna en México fue una historia de desventuras. A pesar de los sucesivos esfuerzos iniciados en 1842 para erigir un observatorio nacional que promoviese el progreso de la ciencia astronómica, el respaldo público y privado fue esporádico, fragmentario, débil y errático. Con la fundación del Observatorio Astronómico Nacional en 1878, las condiciones para hacer estudios astronómicos mejoraron; sin embargo, las circunstancias económicas, políticas e intelectuales de la época no fueron las adecuadas para que los astrónomos locales se incorporaran al vigoroso proceso de crecimiento y consolidación de la astrofísica moderna. Esto cambió apenas en 1942, con la fundación del Observatorio Astrofísico de Tonantzintla. En esa oportunidad se sentaron las bases para el establecimiento de la astrofísica en México. La construcción de este observatorio fue posible gracias a la solidaridad del director del Observatorio de la Universidad de Harvard, Harlow Shapley, y al apoyo incondicional del gobierno de México a un grupo de jóvenes científicos mexicanos, encabezado por Luis Enrique Erro, que trabajaron arduamente para actualizar la astronomía local. Dicho proceso tuvo lugar entre 1938 y 1942, en medio de una situación interna muy particular de la política mexicana y de los problemas geopolíticos planteados por la Segunda Guerra Mundial.
The Political Origins of Social Security in Mexico during the Cárdenas and Ávila Camacho Administrations
Authors: Dion Michelle
Published: April 2005

This study compares efforts to adopt social insurance legislation in the administrations of Lázaro Cárdenas and Manuel Ávila Camacho in Mexico to explain the political origins of the welfare state in Latin America. The author argues that the adoption and implementation of social insurance in Mexico was the outcome of an implicit bargain between organized labor and the state following the 1940 presidential election. This bargain signifies the rebuilding by the Ávila Camacho administration of the cross-class coalition originally designed by President Cárdenas and jeopardized by the nationalization of petroleum and presidential succession struggles of the late 1930s.

Este trabajo compara esfuerzos a implantar legislación del seguro social en las administraciones de Lázaro Cárdenas y de Manuel Ávila Camacho en México para explicar los orígenes políticos del Estado de bienestar en América Latina. La autora discute que la adopción y la implantación del seguro social en México fueron resultados de un negocio implícito entre la clase trabajadora organizada y el Estado que seguía la elección presidencial de 1940. Este negocio significa la reconstrucción por la administración de Ávila Camacho de la coalición de clases diseñada por presidente Cárdenas y comprometida originalmente por la nacionalización del petróleo y de las luchas de la sucesión presidencial de los finales de los 30s.
Decadence and the Organic Metaphor
Authors: DAVIS WHITNEY
Published: April 2005

ABSTRACT While Charles Darwin's evolutionary account of organic decay, decline, and extinction provided a model for accounts of supposedly similar processes in the domain of human culture and society, Darwin's own theory of natural selection depended on models of cultural and social transformation, degeneration, and destruction. In the full circuit of the organic metaphor of decadence, then, a theory of culture was applied to nature and then re-applied to the cultural world even though cultural forms do not always literally display processes of organic morbidity, and natural forms do not always literally display the results of intentional human artistry, cultivation, and collection. The organic metaphor of decadence was some-times used to imagine a continuous and regenerating life; sometimes, however, the organic metaphor was used to imagine the necessity of all-pervasive death. The essay compares and contrasts these two approaches—exemplified, on the one hand, by Darwin's own writings and, on the other hand, by Joris-Karl Huysmans's Against Nature.
Cancer Incidence among Workers Potentially Exposed to Chlorinated Solvents in an Electronics Factory
Authors: Chang Yung‐Ming , Tai Chi‐Fu , Yang Sweo‐Chung , Lin Ruey S. , Sung Fung‐Chang , Shih Tung‐Sheng , Liou Saou‐Hsing
Published: April 2005

Cancer Incidence among Workers Potentially Exposed to Chlorinated Solvents in an Electronics Factory: Yung‐Ming Chang, et al. Graduate Institute of Life Sciences, National Defense Medical Center, National Defense University, Taiwan, R.O.C.—A retrospective cohort morbidity study based on standardized incidence ratios (SIRs) was conducted to investigate the possible association between exposure to chlorinated organic solvents and various types of cancers in an electronics factory. The cohort of the exposed group was retrieved from the Bureau of Labor Insurance (BLI) computer database records dating from 1978 through December 31, 1997. Person‐year accumulation began on the date of entry to the cohort, or January 1, 1979 (whichever came later), and ended on the closing date of the study (December 31, 1997), if alive without contracting any type of cancers, or the date of death, or the date of the cancer diagnosis. Vital status and cases of cancer of study subjects were determined from January 1, 1979 to December 31, 1997 by linking cohort data with the National Cancer Registry Database. The cancer incidence of the general population was used for comparison. After adjustment for age and calendar year, only SIR for breast cancer in the exposed female employees were significantly elevated when compared with the Taiwanese general population, based on the entire cohort without exclusion. The SIR of female breast cancer also showed a significant trend of period effect, but no significant dose‐response relationship on duration of employment. Although the total cancer as well as the cancer for trachea, bronchus and lung for the entire female cohort was not significantly elevated, trend analysis by calendar‐year interval suggested an upward trend. However, when duration of employment or latency was taken into consideration, no significantly elevated SIR was found for any type of cancer in either male or female exposed workers. In particular, the risk of female breast cancer was not indicated to be increased. No significant dose‐response relationship on duration of employment and secular trend was found for the above‐mentioned cancers. This study provides no evidence that exposure to chlorinated organic solvents at the electronics factory was associated with elevated human cancers. Dominant short‐term employees may bias the cancer risk toward false positive.
Effects of Waterfall Dimensions and Light Intensity on Age‐0 Brook Trout Jumping Performance
Authors: Brandt Mandi M. , Holloway J. Preston , Myrick Christopher A. , Kondratieff Matthew C.
Published: April 2005

We conducted three experiments to understand the effects of (1) waterfall design (width, height, and plunge pool depth) and (2) light intensity on the ability of age‐0 brook trout Salvelinus fontinalis to successfully jump over small waterfalls or vertical obstacles, such as pool‐and‐weir fishways. We measured the jumping performance of brook trout as a function of waterfall height (2–24 cm), plunge pool depth (8–18 cm), and fish size (total length (TL), mm). Waterfall height and TL had the largest effects on jumping performance. Maximum heights jumped decreased as waterfall height increased or TL decreased. Our second experiment measured the effects of waterfall widths of 10, 20, and 30 cm on age‐0 brook trout jumping ability for a fixed waterfall height of 20 cm and a plunge pool depth of 40 cm. Significantly fewer fish jumped through the 10‐cm‐wide waterfall than through either the 20‐ or 30‐cm‐wide waterfalls. Our third experiment measured the jumping success of brook trout at light levels of 0, 0.23, and 1.70 lx/μA. Brook trout successfully jumped over 4‐ and 20‐cm‐high waterfalls at all light intensities, providing evidence that they can see very well under low light conditions and may also use senses like the acoustico‐lateralis system to help them negotiate obstacles. We conclude that narrow waterfalls with heights more than three body lengths and shallow plunge pools will probably restrict the movement of age‐0 brook trout, while light intensity does not appear to have much of an impact on their movements.
Preoperative Assessment of Surgical Risk in Oncogeriatric Patients
Authors: Audisio Riccardo A. , Ramesh Hodigere , Longo Walter E. , Zbar Andrew P. , Pope Daniel
Published: April 2005

Cancer is a prevalent disease in our aging population; however, few oncologists are familiar with caring for oncogeriatric patients. Surgery is presently the treatment of choice for most solid tumors, but it is frequently delivered in a suboptimal way in this patient subsetting. Undertreatment is often justified with the concern of an unsustainable toxicity, while overtreatment can be related to the lack of knowledge in optimizing preoperative risk assessment. To draw new light on this issue, several surgeons presented their series, providing hard evidence that surgical options can be offered to the elderly with cancer, with only a limited postoperative mortality and morbidity. As it is likely that much of these data suffer from selection bias, we concentrated on Comprehensive Geriatric Assessment (CGA), which can add substantial information on the functional assessment of elderly cancer patients. A validated instrument such as the CGA allows a comparison of series, predicting short-term surgical outcomes more precisely, and offers appropriate information when consenting elderly patients. Preoperative Assessment of Cancer in the Elderly is a prospective international study conceived and launched to outline the fitness of elderly surgical patients with malignant tumors. This paper reports on preliminary results and analysis from the ongoing study.
T-Cell Lymphoma of the Rectum in a Patient with AIDS and Hepatitis C: A Case Report and Discussion
Authors: Tisdale Gus , Mahadevan Anand , Matthews Richard H.
Published: April 2005

Primary T-cell non-Hodgkin's lymphoma (NHL) occurring in the context of acquired immune deficiency syndrome (AIDS) is uncommon. Here, we report and discuss such a case presenting in the rectum, and review relevant literature. Although typical in some respects, the case is, in other ways, somewhat unusual for an AIDS-related NHL (ARL); ARL tends to be B cell and advanced stage and our case was T cell and stage IE. In addition, the patient suffered from concomitant cirrhosis related to hepatitis C. Chemotherapeutic options for ARL were limited early in the AIDS epidemic due to poor tolerability. Although this has largely been mitigated by the advent of highly active antiretroviral therapy, our patient eventually suffered complications of chemotherapy, apparently related more to his liver disease than to either his lymphoma or AIDS, that ultimately brought about his demise.
Regulation of functional steroid receptors and ligand-induced responses in telomerase-immortalized human endometrial epithelial cells
Authors: Hombach-Klonisch S , Kehlen A , Fowler P A , Huppertz B , Jugert J F , Bischoff G , Schlüter E , Buchmann J , Klonisch T
Published: April 2005

Information on the regulation of steroid hormone receptors and their distinct functions within the human endometrial epithelium is largely unavailable. We have immortalized human primary endometrial epithelial cells (EECs) isolated from a normal proliferative phase endometrium by stably transfecting the catalytic subunit (hTERT) of the human telomerase complex and cultured these hTERT-EECs now for over 350 population doublings. Active hTERT was detected in hTERT-EECs employing the telomerase repeat amplification assay protocol. hTERT-EECs revealed a polarized, non-invasive epithelial phenotype with apical microvilli and production of a basal lamina when grown on a three-dimensional collagen–fibroblast lattice. Employing atomic force microscopy, living hTERT-EECs were shown to produce extracellular matrix (ECM) components and ECM secretion was modified by estrogen and progesterone (P4). hTERT-EECs expressed inducible and functional endogenous estrogen receptor-alpha (ER-alpha) as demonstrated by estrogen response element reporter assays and induction of P4 receptor (PR). P4 treatment down-regulated PR expression, induced MUC-1 gene activity and resulted in increased ER-beta transcriptional activity. Gene activities of cytokines and their receptors interleukin (IL)-6, leukemia inhibitory factor (LIF), IL-11 and IL-6 receptor (IL6-R), LIF receptor and gp130 relevant to implantation revealed a 17 beta-estradiol (E2)-mediated up-regulation of IL-6 and an E2- and P4-mediated up-regulation of IL6-R in hTERT-EECs. Thus, hTERT-EECs may be regarded as a novel in vitro model to investigate the role of human EECs in steroid hormone-dependent normal physiology and pathologies, including implantation failure, endometriosis and endometrial cancer.
Gene regulation by NMDA receptor activation in the SDN-POA neurons of male rats during sexual development
Authors: Hsu Hseng-Kuang , Shao Pei-Lin , Tsai Ke-Li , Shih Huei-Chuan , Lee Tzu-Ying , Hsu Chin
Published: April 2005

The present study was designed to identify possible signaling pathways, which may play a role in prevention of neuronal apoptosis in the sexually dimorphic nucleus of the preoptic area (SDN-POA) after physiological activation of the N-methyl-D-aspartate (NMDA) receptor. Gene response to the blockage of the NMDA receptor by an antagonist (dizocilpine hydrogen maleate; MK-801) was screened after suppression subtractive hybridization (SSH). The results showed that dfferential screening after SSH detected the presence of some neurotrophic genes (RNA binding motif protein 3 (RBM3), α-tubulin) as well as apoptosis-related genes (Bcl-2, cytochrome oxidase subunit II, cytochrome oxidase subunit III) in the SDN-POA of male rats, which were down-regulated by blocking the NMDA receptor. The RT-PCR products of the aforementioned genes in MK-801-treated males were significantly less than that in untreated males. In particular, the expression of Bcl-2 mRNA, including Bcl-2 protein, in male rats were significantly suppressed by MK-801 treatment. Moreover, the binding activity of nuclear factor κB (NFκB) was significantly higher in male rats than in females, but significantly diminished by blocking the NMDA receptor with MK-801 in male rats. No significant difference in cAMP response element-binding protein (CREB) binding activity was observed among untreated male, MK-801-treated male, untreated female and MK-801-treated female groups. These results suggest that genes regulated by NMDA receptor activation might participate in neuronal growth and/or anti-apoptosis, and support an important signaling pathway of NFκB activation and its target gene, Bcl-2, in preventing neuronal apoptosis in the SDN-POA of male rats during sexual development.
The −514 C/T polymorphism in the hepatic lipase gene promoter is associated with insulin sensitivity in a healthy young population
Authors: Gómez Purificación , Pérez-Jiménez Francisco , Marín Carmen , Moreno Juan Antonio , Gómez María José , Bellido Cecilia , Pérez-Martínez Pablo , Fuentes Francisco , Paniagua Juan Antonio , López-Miranda José
Published: April 2005

Impaired insulin action has been associated with diabetes, dyslipidemia and atherosclerotic vascular disease. The expression of insulin resistance results from the interaction of environmental and genetic factors. Human hepatic lipase (HL) is a lipolytic enzyme that plays a role in the metabolism of several lipoproteins, while insulin up-regulates the activity of HL via insulin-responsive elements in the HL promoter. We have examined the influence of −514 C/T polymorphism in the hepatic lipase gene promoter on insulin sensitivity in 59 healthy young subjects (30 males and 29 females). The volunteers were subjected to three dietary periods, each lasting four weeks. During the first period all subjects consumed a saturated fat (SFA)-enriched diet with 38% as fat (20% SFA, 12% monounsaturated fatty acids (MUFA) and 6% polyunsaturated fatty acids (PUFA)). In the second and third dietary periods, a randomized crossover design was used, consisting of a low fat, high carbohydrate diet (CHO diet) (< 10% SFA, 12% MUFA and 6% PUFA) and a high-MUFA, or Mediterranean diet, with < 10% SFA, 22% MUFA and 6% PUFA. We determined the in vivo insulin resistance using the insulin suppression test with somatostatin. Steady-state plasma glucose (SSPG) concentrations (a measure of insulin sensitivity) were significantly higher in men carriers of the −514T allele after the consumption of the SFA diet than after the CHO diet and the Mediterranean diet. This effect was not observed in women. Moreover, there were no significant differences in insulin sensitivity after the three diets in men and women with the CC genotype. In summary, our results show an improvement in insulin sensitivity in men with the −514T allele of the HL promoter polymorphism, when MUFA and carbohydrates are consumed instead of SFA fat.
Atrial natriuretic peptide inhibits the actions of FSH and forskolin in meiotic maturation of pig oocytes via different signalling pathways
Authors: Zhang M , Tao Y , Zhou B , Xie H , Wang F , Lei L , Huo L , Sun Q , Xia G
Published: April 2005

Atrial natriuretic peptide (ANP) as well as its receptors is found in mammalian ovary and follicular cells and its function in oocyte meiotic maturation has also been reported in Xenopus, hamster and rat. But the results are controversial and the physiological mechanism of ANP on oocyte maturation is not clear, especially the relationship between gonadotrophin and ANP as well as the signal transduction, and these need further study. The present study conducted experiments to examine these questions by using drug treatment and Western blot analysis and focused on pig oocyte meiotic maturation and cumulus expansion in vitro. The results revealed that ANP could inhibited FSH-induced pig oocyte maturation and cumulus expansion and prevent the full phosphorylation of mitogen-activated protein kinase in both oocytes and cumulus cells, and that these inhibitory effects could be mimicked by 8-Br-cyclic guanosine 5′-monophosphate (8-Br-cGMP), but blocked by a protein kinase G (PKG) inhibitor KT5823. Zaprinast, a cGMP-specific phosphodiesterase inhibitor, could enhance the inhibitory effect of ANP on oocyte maturation. A specific analogue of ANP, C-ANP-(4–23), which binds to the natriuretic peptide receptor-C (NPRC), had no effect in either FSH-induced or spontaneous oocyte maturation. Treatment with forskolin, a stimulator of adenylate cyclase, had a biphasic effect; 44 h treatment induced cumulus expansion but inhibited oocyte maturation while 2 h treatment induced maturation of cumulus-enclosed oocytes (CEOs). Both ANP and C-ANP-(4–23) could inhibit the effect of forskolin on CEO maturation, and these inhibitory effects of ANP/C-ANP-(4–23) could be blocked by preincubation with pertussis toxin (PT), consistent with mediation by a Gi protein(s) in the cumulus cells. All these results suggest that ANP is a multifunctional regulator of FSH and forskolin on pig CEO maturation by two signalling mechanisms: one is via a cGMP/PKG pathway, the other is via NPRC receptors in cumulus cells and the activation of the PT-sensitive Gi protein(s).
Linking the ubiquitin–proteasome pathway to chromatin remodeling/modification by nuclear receptors
Authors: Kinyamu H K , Chen J , Archer T K
Published: April 2005

Over 25 years ago, eukaryotic cells were shown to contain a highly specific system for the selective degradation of short-lived proteins, this system is known as the ubiquitin–proteasome pathway. In this pathway, proteins are targeted for degradation by covalent modification by a small highly conserved protein named ubiquitin. Ubiquitin-mediated degradation of regulatory proteins plays an important role in numerous cell processes, including cell cycle progression, signal transduction and transcriptional regulation. Recent experiments have shown that the ubiquitin–proteasome pathway is also involved in nuclear hormone receptor (NR)-mediated transcriptional regulation. The idea that the ubiquitin–proteasome pathway is involved in NR-mediated transcription is strengthened by experiments showing that ubiquitin–proteasome components are recruited to NR target gene promoters. However, it is not clear how these components modulate NR-mediated chromatin remodeling and gene expression. In this review, we postulate the role of the ubiquitin–proteasome pathway on NR-mediated chromatin remodeling and gene regulation based on the current knowledge from studies implicating the pathway in chromatin structure modifications that are applicable to NR function. Since evidence from this laboratory, using the glucocorticoid receptor responsive mouse mammary tumor virus (MMTV) promoter organized as chromatin, suggest that the ubiquitin–proteasome system may be involved in the elongation phase of transcription, we particularly concentrate on chromatin modifications associated with the elongation phase.
Inducible upregulation of oestrogen receptor-β1 affects oestrogen and tamoxifen responsiveness in MCF7 human breast cancer cells
Authors: Murphy L C , Peng B , Lewis A , Davie J R , Leygue E , Kemp A , Ung K , Vendetti M , Shiu R
Published: April 2005

To investigate the effect of altered oestrogen receptor (ER)α and ERβ expression on oestrogen and anti-oestrogen action in breast cancer, we have stably expressed an inducible ERβ1 in MCF7 breast cancer cells. Stably expressing clones were isolated and over-expression of ERβ1 correlated with increased levels of specific radiolabelled oestradiol (E2) binding. Increased ERβ1 did not affect endogenous levels of ERα but increased progesterone receptor (PR) levels. Over-expression of ERβ1 reduced growth responses to E2 in contrast to little if any effect of over-expression of ERα. In oestrogen-replete conditions, over-expression of ERβ1 but not ERα reduced proliferation. Over-expression of ERβ1 did not result in anti-oestrogen resistance but was associated with increased sensitivity to 4-hydroxytamoxifen. Our results suggested that over-expression of ERβ1 in the presence of an endogenously expressed ERα was associated with tamoxifen sensitivity but may negatively modulate ERα-mediated growth. However, not all ERα activities were inhibited since endogenous PR expression was increased by both ERα and ERβ1 over-expression. These data paralleled those seen in some in vivo studies showing a relationship between PR and ERβ expression as well as ERβ expression and tamoxifen sensitivity of ER-positive breast cancer patients. These models are relevant and will be useful for dissecting the role of ERβ1 expression in ER-positive breast cancer.
Experimental and bioinformatic approaches for interrogating protein–protein interactions to determine protein function
Authors: Droit Arnaud , Poirier Guy G , Hunter Joanna M
Published: April 2005

An ambitious goal of proteomics is to elucidate the structure, interactions and functions of all proteins within cells and organisms. One strategy to determine protein function is to identify the protein–protein interactions. The increasing use of high-throughput and large-scale bioinformatics-based studies has generated a massive amount of data stored in a number of different databases. A challenge for bioinformatics is to explore this disparate data and to uncover biologically relevant interactions and pathways. In parallel, there is clearly a need for the development of approaches that can predict novel protein–protein interaction networks in silico. Here, we present an overview of different experimental and bioinformatic methods to elucidate protein–protein interactions.
A conserved retinoid X receptor (RXR) from the mollusk Biomphalaria glabrata transactivates transcription in the presence of retinoids
Authors: Bouton D , Escriva H , de Mendonça R L , Glineur C , Bertin B , Noël C , Robinson-Rechavi M , de Groot A , Cornette J , Laudet V , Pierce R J
Published: April 2005

Retinoid X receptors (RXR) are members of the nuclear receptor superfamily of ligand-activated transcription factors that have been characterized in a wide variety of metazoan phyla. They act as heterodimer partners of other nuclear receptors, and in vertebrates also activate transcription as homodimers in the presence of a ligand, 9-cis retinoic acid. In order to test the hypothesis that retinoic acid signaling pathways involving RXRs are present in the Lophotrochozoa, we have sought to isolate conserved members of this family from the platyhelminth parasite Schistosoma mansoni and its intermediate host, the mollusk Biomphalaria glabrata. Here we report that an RXR ortholog from B. glabrata (BgRXR) is better conserved, compared with mouse RXRα, both in the DNA-binding domain (89% identity) and in the ligand-binding domain (LBD) (81% identity), than are arthropod homologs. In EMSA, BgRXR binds to the direct repeat response element DR1 as a homodimer or as a heterodimer with mammalian RARα, LXR, FXR or PPARα. When transfected alone into mammalian cell lines, BgRXR transactivated transcription of a reporter gene from the Apo-A1 promoter in the presence of 9-cis retinoic acid or DHA. Constructs with the Gal4 DNA binding domain fused to the hinge and LBDs of BgRXR were used to show that ligand-dependent activation of transcription by BgRXR required its intact AF-2 activation domain, and that the LBD can form homodimers. Finally, the binding of 9-cis retinoic acid preferentially protected the LBD of BgRXR from degradation by trypsin in a proteolysis protection assay. Our results show that BgRXR binds and is activated by retinoids and suggest that retinoid signaling pathways are conserved in the Lophotrochozoa. The nucleotide sequence reported in this paper has been submitted to the GenBank/EBI Data Bank with accession no. AY048663.
Toxicity assessment of environmentally relevant pollutant mixtures using a heuristic model
Authors: Olmstead Allen W. , LeBlanc Gerald A.
Published: April 2005

In this study, 9 chemicals were chosen from a recent report on surface water concentrations of a variety of xenobiotics to test the hypothesis that the toxicity of chemical mixtures could be estimated using a model based on the toxicity of the individual chemicals. Concentration-response curves for the endpoints of lifespan, growth rate, and fecundity were generated for each chemical experimentally using the crustacean, Daphnia magna. From this data, a mathematical model for the combined toxicity of these chemicals was generated that merged the concepts of concentration addition and independent joint action. Toxicity of a mixture was modeled at various levels at which the ratio of the chemicals within the mixture was maintained at that reported for median detected environmental levels. Toxicity of the mixture was then determined experimentally and compared to model predictions. The model accurately predicted the most sensitive endpoint, as well as the lowest toxic effect level of the mixture. Results demonstrated that, for this mixture of chemicals, toxicity was not influenced significantly by interactions among the chemicals and a single constituent dominated toxicity. According to model predictions and experimental results, the median detected environmental concentrations of chemicals constituting this mixture provided no margin of safety.
Flammability
Authors: Lyon Richard E. , Janssens Marc L.
Published: April 2005

This article provides an overview of polymer flammability from a materials seience perspective and describes currently accepted test methods to quantify burning behavior. Simplifying assumptions about the gas and condensed phase processes of flaming combustion provide mathematical relationships between polymer properties, chemical structure, flame resistance, and fire behavior.
Polymer Vesicles
Authors: Förster Stephan , Borchert Kwe
Published: April 2005

Vesicles are self‐supported closed bilayer assemblies of amphiphiles that enclose an aqueous interior volume. The most important vesicle‐forming amphiphiles are phospholipids formingliposomes, as well as amphiphilic block copolymers formingpolymersomes. Vesicles are investigated with respect to biomedical and cosmetic applications. The article covers energy and kinetic aspects of bilayer and vesicle formation, vesicle preparation methods, classification of vesicle shapes and shape transitions, mechanical properties of vesicle membranes, methods to improve vesicle stability, and biomedical aspects such as loading and sustained or triggered release of encapsulants, reconstitution of membrane proteins, and cell adhesion. An overview of all vesicle‐forming polymers is given. Theoretical concepts such as curvature and elasticity energy are introduced and their consequence for vesicle formation, size, and shape are discussed.
Ionic Liquids, Polymerization in
Authors: Zhang Hongwei , Mays Jimmy W.
Published: April 2005

Room temperature ionic liquids (RTILs) are also call molten salts because they exist in the liquid state at or around room temperature. They are nonvolatile and chemically, thermally, air and moisture stable. They are also noncoordinating and highly polar solvents and have been used extensively as alternative reaction media for various chemical reactions. Reactions in RTILs are often characterized by faster reaction rates and higher selectivities, as compared to those in common organic solvents. Polymerizations in RTILs were not widely investigated until the introduction of the 2nd generation of RTILs. Conventional free radical polymerization and living/controlled radical polymerization in RTILs have both demonstrated the advantages of using RTILs as reaction media in place of common solvents: faster propagation rates, diminished termination, easy product separation, and reduced side reactions. Other types of polymerizations have also been successfully carried out in RTILs. This review summarizes the current status of this rapidly evolving field of research.
Clinical report of a pure subtelomeric 1qter deletion in a boy with mental retardation and multiple anomalies adds further evidence for a specific phenotype
Authors: van Bever Yolande , Rooms Liesbeth , Laridon Annick , Reyniers Edwin , van Luijk Rob , Scheers Stefaan , Wauters Jan , Kooy R. Frank
Published: April 2005

Deletions of the 1q telomere have been reported in several studies screening for subtelomeric rearrangements. However, an adequate clinical description is available from only a few patients. We provide a clinical description of a patient with a subtelomeric deletion of chromosome 1q, previously detected by us in a screening study. Comparison of the clinical presentation of our patient with rare cases reported previously provides further evidence for a specific phenotype of 1q patients, including mental retardation, growth retardation, sometimes with prenatal onset, progressive microcephaly, seizures, hand and foot abnormalities and a variety of midline defects, including corpus callosum, cardiac, genital and gastro–esophageal abnormalities. This clinical presentation is remniscent of that of patients with larger, microscopically visible deletions of chromosome 1q (>3 Mb) characterized by growth and mental retardation, coarse faces with thin upper lip, epilepsy, and variable other anomalies. In addition, the breakpoint region was mapped to a 26 kb region within the RGS7 gene. Among the 17 known genes in the candidate region, are zinc‐finger genes. Other members of this gene family have been implicated in different forms of mental retardation. © 2005 Wiley‐Liss, Inc.