bluuebunny/crossref_metadata_2025 huggingface dataset:
The C‐terminal domain of the human EP4 receptor confers agonist‐induced receptor desensitization in a receptor hybrid with the rat EP3β receptor
Authors: Neuschäfer-Rube Frank , Hänecke Kristina , Püschel Gerhard P
Published: July 2002

Prostaglandin E2 receptors (EPR), which belong to the family of heterotrimeric G protein‐coupled ectoreceptors with seven transmembrane domains, can be classified into four subtypes according to their ligand binding and G protein coupling specificity. Of these, EP3βR is coupled to Gi, whereas EP4R is coupled to Gs. EP4R, in contrast to EP3βR, shows agonist‐induced desensitization. The C‐terminal domain and the third intracellular loop of these receptors have been implicated in G protein coupling specificity and desensitization. Here, receptor hybrids consisting of the main portion of rat EP3βR and either the C‐terminal domain or the third intracellular loop of human EP4R were used to study the contribution of the respective receptor domains to G protein coupling and desensitization. Neither the EP4R C‐terminal domain nor the EP4R third intracellular loop alone was sufficient to change the coupling specificity of the rEP3hEP4 receptor hybrids from Gi to Gs or to confer additional Gs coupling. However, the EP4R C‐terminal domain but not the third intracellular loop was necessary and sufficient to mediate rapid agonist‐induced, second messenger‐independent desensitization in the Gi‐coupled hybrid receptors.
Mitochondrial cytochrome c oxidase subunit IV is phosphorylated by an endogenous kinase
Authors: Steenaart Nancy A.E. , Shore Gordon C.
Published: July 2002

This study was undertaken to identify novel mitochondrial membrane proteins that are potential targets for phosphorylation. Mitochondrial membranes were incubated in the presence of [γ‐32P]ATP and the Triton X‐114 extractable protein was subjected to ion‐exchange and polyacrylamide gel chromatography to purify a major phosphorylated protein of approximately 17 000 Da. The determined peptide sequence of the purified phosphoprotein corresponded to a segment of cytochrome c oxidase subunit IV, an inner membrane protein of 17 160 Da. The identity of the phosphoprotein was confirmed by two‐dimensional electrophoresis and Western blotting. The results identify mitochondrial cytochrome c oxidase subunit IV as a protein which is phosphorylated by an endogenous kinase.
Cell swelling increased the α2‐macroglobulin gene expression in cultured rat hepatocytes
Authors: Meisse Delphine , Renouf Sylvie , Husson Annie , Lavoinne Alain
Published: July 2002

The effect of cell swelling on the expression of the α2‐macroglobulin (α2M) gene was studied in hepatocytes in culture. Hypoosmolarity induced an increase (3‐fold increase) in the level of α2M mRNA through a corresponding stimulation of the rate of transcription of the α2M gene. The addition of raffinose (100 mM) corrected the effect of hypoosmolarity at both mRNA and transcriptional level, demonstrating that cell swelling per se was responsible for the observed effect on the expression of the α2M gene. Moreover, the effect of cell swelling was additive to that of interleukin 6, a major mediator of the acute‐phase response.
Stability of plasminogen activator inhibitor‐1: role of tyrosine221
Authors: Sui Guang-Chao , Wiman Björn
Published: July 2002

Using site‐directed mutagenesis, changes of Tyr221 in plasminogen activator inhibitor‐1 (PAI‐1) have provided mutants with normal activity, but with increased stability. At physiological conditions, the transition of the PAI‐1 mutants Tyr221His and Tyr221Ser to the latent form was significantly prolonged (half‐lives 14.8 and 4.1 h, respectively) as compared to wild‐type PAI‐1 (2.0 h). Their half‐lives, especially for the Tyr221Ser mutant, were even more prolonged in the presence of vitronectin (23.8 and 53.7 h, respectively). While wild‐type PAI‐1 was more stable at lower pH, the PAI‐1 mutants Tyr221His and Tyr221Ser had stability optima at about pH 6.5, but displayed shorter half‐lives at pH 5.5.
Oxygen induces fatty acid (n‐6)‐desaturation independently of temperature in Acanthamoeba castellanii
Authors: Thomas Katie , Rutter Andrew , Suller Marc , Harwood John , Lloyd David
Published: July 2002

Induction of a microsomal oleate Δ12 (n‐6) desaturase which is mainly responsible for an increase in membrane lipid unsaturation at low temperature has been observed in the free‐living amoeba Acanthamoeba castellanii. In this study we show that the enzyme can also be regulated by oxygen independently of temperature in batch cultures grown to O2‐limitation. Raising the oxygen concentration from below the lower limit of detection (<0.1 μM) to approximately air‐saturation (230 μM), whilst maintaining the growth temperature constant (30°C), increased lipid unsaturation and elevated n‐6‐desaturase activity 2.3‐fold. Addition of the protein synthesis inhibitor, anisomycin, showed that increased desaturase activity was due to new protein synthesis rather than activation of pre‐existing enzyme. These observations are important for future studies of the mechanism of temperature adaptation in poikilotherms.
Adrenomedullin production is correlated with differentiation in human leukemia cell lines and peripheral blood monocytes
Authors: Kubo Atsushi , Minamino Naoto , Isumi Yoshitaka , Kangawa Kenji , Dohi Kazuhiro , Matsuo Hisayuki
Published: July 2002

We demonstrated that adrenomedullin (AM) is produced and secreted from human leukemia cell lines (THP‐1 and HL‐60) as well as peripheral blood granulocytes, lymphocytes, monocytes and monocyte‐derived macrophages. Immunoreactive AM accumulated in the culture media of THP‐1 and HL‐60 cells increased according to their differentiation into macrophage‐like cells. Retinoic acid exerted synergistic effects on AM secretion from THP‐1 and HL‐60 cells when administered with tumor necrosis factor‐α, lipopolysaccharide or 12‐O‐tetradecanoyl phorbol‐13‐acetate. AM was shown to increase the scavenger receptor activity on THP‐1 cells. Thus, monocytes/macrophages should be recognized as sources of AM, and the secreted AM may modulate the function of macrophages.
A G·U base pair in the eukaryotic selenocysteine tRNA is important for interaction with SePF, the putative selenocysteine‐specific elongation factor
Authors: Mizutani Takaharu , Tanabe Kazutaka , Yamada Kenichiro
Published: July 2002

In Escherichia coli, selenocysteine biosynthesis and incorporation into selenoproteins requires the action of four gene products, including the specialized selenocysteine tRNASec and elongation factor SELB, different from the universal EF‐Tu. In this regard, the situation is less clear in eukaryotes, but we previously reported the existence of SePF, a putative SELB homologue. The secondary structure of the tRNASec differs slightly in eukaryotes, due to a change in the lengths of several stems. Two non‐Watson‐Crick base pairs, G5a·U67b and U6·U67, reside in the acceptor stem and are conserved in the course of evolution. Since it has already been reported that changing them to Watson‐Crick base pairs did not affect the serylation or selenylation levels of tRNASec, we asked whether these non‐Watson‐Crick base pairs are required for the interaction with SePF. To this end, tRNASec variants carrying Watson‐Crick changes at these positions were tested for their ability to maintain the interaction with SePF. In these assays, the tRNASec‐SePF interaction was determined by the protective action it confers against hydrolysis of the amino acid ester bond, under basic conditions. All the changes introduced at U6·U67 did not significantly affect the interaction. Interestingly, however, the G5a·U67b to G5a‐C67b substitution was sufficient, by itself, to lead to unprotection of the ester bond. Therefore, our finding strongly suggests that SePF is unable to interact with a tRNASec mutant version carrying a Watson‐Crick G5a‐C67b instead of the wild‐type G5a·U67b base pair, establishing that G5a·U67b constitutes a structural determinant for SePF interaction.
Functional characterization of Kunitz domains in hepatocyte growth factor activator inhibitor type 2
Authors: Qin Li , Denda Kimitoshi , Shimomura Takeshi , Kawaguchi Toshiya , Kitamura Naomi
Published: July 2002

Hepatocyte growth factor activator inhibitor type 2 (HAI‐2) was identified as a potent inhibitor of hepatocyte growth factor activator (HGF activator). The primary translation product of HAI‐2 contains two Kunitz domains. To characterize their function, we introduced a point mutation into the reactive site of each Kunitz domain, and assayed the mutants for their HGF activator inhibitory activity. A point mutation in the COOH‐terminal Kunitz domain did not affect the activity of HAI‐2, whereas a point mutation in the NH2‐terminal Kunitz domain markedly reduced the activity. These results suggest that the NH2‐terminal Kunitz domain is mainly responsible for the HGF activator inhibitory activity of HAI‐2.
Insulin‐independent glucose transport regulates insulin sensitivity
Authors: Ebeling Pertti , Koistinen Heikki A , Koivisto Veikko A
Published: July 2002

The glucose transport proteins (GLUT1 and GLUT4) facilitate glucose transport into insulin‐sensitive cells. GLUT1 is insulin‐independent and is widely distributed in different tissues. GLUT4 is insulin‐dependent and is responsible for the majority of glucose transport into muscle and adipose cells in anabolic conditions. We suggest the hypothesis that insulin resistance is dependent on whether glucose is entering through GLUT1 or GLUT4 and on the two functional compartments of glucose 6‐phosphate formation within the cell. Glucose entering the muscle cell through GLUT4 and phosphorylated by hexokinase II is mainly directed to glycogen synthesis and glycolysis. If glucose is entering through GLUT1 and phosphorylated by hexokinase I, the glucose 6‐phosphate so formed is available for all metabolic pathways, including the hexosamine pathway. Hexosamines have a negative feedback effect on GLUT4, and reduced GLUT4 activity decreases insulin‐mediated glucose uptake. Thus, insulin‐independent glucose transport through GLUT1 can meet the basal needs of the muscle cell. If glucose entrance through GLUT1 and the activation of the hexosamine pathway is abundant, it can decrease the insulin‐mediated glucose transport through GLUT4 leading to insulin resistance.
Rapid cytochrome c release, activation of caspases 3, 6, 7 and 8 followed by Bap31 cleavage in HeLa cells treated with photodynamic therapy
Authors: Granville David J , Carthy Chris M , Jiang Huijun , Shore Gordon C , McManus Bruce M , Hunt David W.C
Published: July 2002

Photodynamic therapy (PDT) is a clinical approach that utilizes light‐activated drugs for the treatment of a variety of pathologic conditions. The initiating events of PDT‐induced apoptosis are poorly defined. It has been shown for other pro‐apoptotic stimuli that the integral endoplasmic reticulum protein Bap31 is cleaved by caspases 1 and 8, but not by caspase‐3. Further, a 20 kDa Bap31 cleavage fragment is generated which can induce apoptosis. In the current report, we sought to determine whether Bap31 cleavage and generation of p20 is an early event in PDT‐induced apoptosis. The mitochondrial release of cytochrome c, involvement of caspases 1, 2, 3, 4, 6, 7, 8, and 10 and the status of several known caspase substrates, including Bap31, were evaluated in PDT‐treated HeLa cells. Cytochrome c appeared in the cytosol immediately following light activation of the photosensitizer benzoporphyrin derivative monoacid ring A. Activation of caspases 3, 6, 7, and 8 was evident within 1–2 h post PDT. Processing of caspases 1, 2, 4, and 10 was not observed. Cleavage of Bap31 was observed at 2–3 h post PDT. The caspase‐3 inhibitor DEVD‐fmk blocked caspase‐8 and Bap31 cleavage suggesting that caspase‐8 and Bap31 processing occur downstream of caspase‐3 activation in PDT‐induced apoptosis. These results demonstrate that release of mitochondrial cytochrome c into the cytoplasm is a primary event following PDT, preceding caspase activation and cleavage of Bap31. To our knowledge, this is the first example of a chemotherapeutic agent inducing caspase‐8 activation and demonstrates that caspase‐8 activation can occur after cytochrome c release.
The SH2 domain containing inositol 5‐phosphatase SHIP2 displays phosphatidylinositol 3,4,5‐trisphosphate and inositol 1,3,4,5‐tetrakisphosphate 5‐phosphatase activity
Authors: Pesesse Xavier , Moreau Colette , Drayer A.Lyndsay , Woscholski Rüdiger , Parker Peter , Erneux Christophe
Published: July 2002

Distinct forms of inositol and phosphatidylinositol polyphosphate 5‐phosphatases selectively remove the phosphate from the 5‐position of the inositol ring from both soluble and lipid substrates. SHIP1 is the 145‐kDa SH2 domain‐containing inositol 5‐phosphatase expressed in haematopoietic cells. SHIP2 is a related but distinct gene product. We report here that SHIP2 can be expressed in an active form both in Escherichia coli and in COS‐7 cells. A truncated 103‐kDa recombinant protein could be purified from bacteria that display both inositol 1,3,4,5‐tetrakisphosphate (InsP4) and phosphatidylinositol 3,4,5‐trisphosphate (PtdIns(3,4,5)P3) phosphatase activities. COS‐7 cell lysates transfected with SHIP2 had increased PtdIns(3,4,5)P3 phosphatase activity as compared to the vector alone.
Arfaptin 1, an ARF‐binding protein, inhibits phospholipase D and endoplasmic reticulum/Golgi protein transport
Authors: Williger Ben-Tsion , Ostermann Joachim , Exton J.H.
Published: July 2002

Class I ADP‐ribosylation factors (ARFs) are essential for coatomer and clathrin coat assembly and vesicular transport in the Golgi apparatus. However, little is known about the in vivo regulation of ARF actions. Recently we cloned arfaptin 1, a 39 kDa protein that binds active, GTPγS‐liganded ARF and translocates with it to Golgi membranes. Here we show that phorbol ester‐stimulated phospholipase D (PLD) activity is inhibited in arfaptin 1‐overexpressing NIH 3T3 cells and that arfaptin 1 inhibits ARF activation of Golgi‐associated PLD. Since PLD activity is thought to play a role in regulating vesicular transport in the secretory pathway, we determined the rate of glycosylation of vesicular stomatitis virus glycoprotein as a measure of protein transport from the endoplasmic reticulum through the Golgi apparatus. Arfaptin 1 overexpression was found to decrease the rate of this reaction approximately two‐fold. These data suggest that arfaptin 1 is a regulator of ARF action in the Golgi apparatus.
DNA binding protein dbpA binds Cdk5 and inhibits its activity
Authors: Moorthamer Mark , Zumstein-Mecker Sabine , Chaudhuri Bhabatosh
Published: July 2002

Progress in the cell cycle is governed by the activity of cyclin dependent kinases (Cdks). Unlike other Cdks, the Cdk5 catalytic subunit is found mostly in differentiated neurons. Interestingly, the only known protein that activates Cdk5 (i.e. p35) is expressed solely in the brain. It has been suggested that, besides its requirement in neuronal differentiation, Cdk5 activity is induced during myogenesis. However, it is not clear how this activity is regulated in the pathway that leads proliferative cells to differentiation. In order to find if there exists any Cdk5‐interacting protein, the yeast two‐hybrid system was used to screen a HeLa cDNA library. We have determined that a C‐terminal 172 amino acid domain of the DNA binding protein, dbpA, binds to Cdk5. Biochemical analyses reveal that this fragment (dbpA(CΔ)) strongly inhibits p35‐activated Cdk5 kinase. The protein also interacts with Cdk4 and inhibits the Cdk4/cyclin D1 enzyme. Surprisingly, dbpA(CΔ) does not bind Cdk2 in the two‐hybrid assay nor does it inhibit Cdk2 activated by cyclin A. It could be that dbpA's ability to inhibit Cdk5 and Cdk4 reflects an apparent cross‐talk between distinct signal transduction pathways controlled by dbpA on the one hand and Cdk5 or Cdk4 on the other.
Metabolism of progesterone to DOC, corticosterone and 18OHDOC in cultured human melanoma cells
Authors: Slominski Andrzej , Gomez-Sanchez Celso E. , Foecking Mark F. , Wortsman Jacobo
Published: July 2002

We are now showing that cultured human melanoma cells can synthesize steroids such as corticosterone from progesterone or deoxycorticosterone. Corticosterone production is strongly responsive to deoxycorticosterone substrate addition (12‐fold increase), but unresponsive to the adrenal stimulating factors ACTH and angiotensin II. This is the first demonstration that skin cells (malignant melanocytes) have the capability to synthesize 11‐deoxycorticosterone, corticosterone, and 18‐hydroxydeoxycorticosterone.
Interaction between a mutant release factor one and P‐site peptidyl‐tRNA is influenced by the identity of the two bases downstream of the stop codon UAG
Authors: Zhang Shaoping , Rydén-Aulin Monica , Isaksson Leif A
Published: July 2002

Termination efficiency of a mutant form of RF (release facor) 1, as compared to the wild‐type enzyme, is influenced by the P‐site peptidyl‐tRNA if the termination signal is UAGA. This effect is weaker at the stronger termination signal UAGU. Similarly, low efficiency of the mutant RF1, together with certain peptidyl‐tRNAs, can be increased by changing the second base of the 3′‐flanking codon from C to G. The data suggest that the mutant RF1 interacts with the P‐site peptidyl‐tRNA in conjunction with the context at the 3′‐side of the termination codon.
Tropoelastin binding to fibulins, nidogen‐2 and other extracellular matrix proteins
Authors: Sasaki Takako , Göhring Walter , Miosge Nicolai , Abrams William R , Rosenbloom Joel , Timpl Rupert
Published: July 2002

Elastic fibers in vessel walls and other tissues consist of cross‐linked tropoelastin in association with several microfibrillar proteins. In order to understand the molecular basis of these structures, we examined the binding of recombinant human tropoelastin to other extracellular matrix ligands in solid phase binding and surface plasmon resonance assays. These studies demonstrated a particularly high affinity (K
d about 1 nM) of tropoelastin for microfibrillar fibulin‐2 and the recently described nidogen‐2 isoform. More moderate affinities were observed for fibulin‐1, laminin‐1 and perlecan, while several other ligands such as collagens, nidogen‐1, fibronectin and BM‐40 showed little or no binding. In immunogold staining of mouse aortic media, elastic fibers were heavily decorated with tropoelastin, fibulin‐2 and nidogen‐2, while the reaction with fibulin‐1 was lower. The colocalization of these proteins emphasizes the potential for in vivo interactions.
The mammalian homologues of frog Bv8 are mainly expressed in spermatocytes
Authors: Wechselberger Christian , Puglisi Rossella , Engel Edwin , Lepperdinger Günter , Boitani Carla , Kreil Günther
Published: July 2002

Bv8, a protein from skin secretions of Bombina variegata, reacts with receptors present in mammalian brain and intestine (Mollay et al. (1999) Eur. J. Pharmacol. 374, 189–196). As deduced from cloned cDNAs, the murine and human Bv8 homologues have identical amino‐terminal sequences and also contain 10 cysteines. From mouse testes, two forms of Bv8 mRNA have been characterized, of which one contains an additional exon which codes for 21 mostly basic amino acids. The mouse Bv8 gene is most active in mid‐late pachytene spermatocytes. In mouse testes, Bv8 mRNA can first be detected at the end of the second week post partum.
Formation of cyclopentenones from all‐(E) hydroperoxides of linoleic acid via allene oxides. New insight into the mechanism of cyclization
Authors: Grechkin Alexander N. , Hamberg Mats
Published: July 2002

Conversions of (Z,E)‐ and (E,E)‐isomers of linoleic acid 13‐ and 9‐hydroperoxides with flax and maize allene oxide synthase were studied. All‐(E) but not (Z,E) hydroperoxides readily undergo cyclization via allene oxides into trans‐cyclopentenones. These results suggest that double bond geometry dramatically affects the formation of pericyclic pentadienyl cation intermediate and thus the capability of 18:2‐allene oxides to undergo electrocyclization into cyclopentenones.
Pregnancy following uterine fibroid embolization
Authors: McLucas B , Goodwin S , Adler L , Rappaport A , Reed R , Perrella R
Published: July 2002

Objective: This paper seeks to evaluate the ability to deliver term pregnancies following uterine fibroid embolization, and to identify impediments to pregnancy in the embolization procedure. Study design: Four physicians performed embolization procedures at various facilities. Patients were asked if fertility was an issue prior to embolization. We measured follicle‐stimulating hormone levels before and after embolization. Clinical follow‐up, six months following embolization was obtained by interview. Patients were questioned regarding attempts to conceive, menstrual history, and subsequent pregnancy. Main outcome measures: Complications were calculated upon the entire patient population, whether or not fertility was identified as a goal. Fertility risks from embolization were identified. We measured radiation exposure in a random consecutive group of 50 women undergoing embolization. All patients who conceived were asked the details of the pregnancy. Results: Four hundred women underwent uterine fibroid embolization between 1996 and 1999. One hundred and thirty nine patients stated a desire for fertility after embolization. Of these, 52 were <40 years old. Seventeen pregnancies have been reported in 14 women. Five spontaneous abortions were observed. Ten women have had normal term deliveries and two women are currently pregnant. No perfusion problems, either during the pregnancy or labor, were reported. The average radiation dosage calculated for 50 women undergoing embolization was 14 rads. Four women under 45 years old suffered premature menopause (10/1000). Two women underwent hysterectomy as a complication of embolization (5/1000). Conclusion: The risks of infertility following embolization, premature menopause, and hysterectomy are small, as is the radiation exposure during embolization. These risks compare favorably with those associated with myomectomy. Fertility rates appear similar to patients undergoing myomectomy. No problems, either during pregnancy or delivery, have been observed after embolization. The course of pregnancy and delivery was normal after embolization with no maternal or fetal complications reported. These findings confirm results from other centers. Desire for future pregnancy is not a contraindication to fibroid embolization.
A socio‐technical systems approach to cell design: case study and analysis
Authors: Hyer Nancy Lea , Brown Karen A , Zimmerman Sharon
Published: July 2002

There exists a large and growing body of academic research exploring various facets of cell design. Most of this research adopts a micro‐level focus, investigating one or a few issues within this large and complex process. Further, most of this research can be characterized as technically focused, giving only limited attention to the significant human dimensions. This has led to a situation where we know a great deal about certain steps in technical design of cells (for example, how to form machine groups and parts families among small data sets), but lack a well‐developed and broadly‐focused theory of cell design and its human consequences. Based on a review of both existing cell design approaches and socio‐technical systems (STS) theory literature, this paper proposes a comprehensive model of cell system design that considers both technical and social dimensions. We illustrate the viability of this model via an observational case study of a very successful cell manufacturing implementation effort in a Fortune 500 company. We highlight the ways in which STS principles influenced and enhanced the cell system design and draw conclusions about the elements of cell system design which appear to be the most significant determinants of sustainable success.
Trabecular bone strain changes associated with cartilage defects in the proximal and distal tibia
Authors: McKinley Todd O. , Bay Brian K.
Published: July 2002

Intraarticular fractures with cartilage defects can lead to post‐traumatic arthritis (PTA). The purpose of this study was to determine how cartilage defects affect load transmission through subchondral trabecular bone in human cadaveric knees and ankles to further understand the pathomechanics of PTA. We created full‐thickness cartilage defects in the meniscectomized proximal tibia and distal tibia and measured changes in trabecular bone strain using Texture Correlation. Texture Correlation compares high quality digital images made from contact radiographs of unloaded samples to images of the same sample under load to measure trabecular bone strain. Cartilage defects caused trabecular bone strain to decrease in the proximal tibia and increase in the distal tibia. The column of bone directly beneath the defect in the tibial plateau had the most significant reduction in strain. In the distal tibia, strain near the jointline and in the anterior third had the most significant increases in strain. The distal tibia had greater strain changes with small defects. The clinical course of intraarticular fractures of the proximal and distal tibia are markedly different. We postulate that disturbances in load transmission through the subchondral bone caused by cartilage defects may be important mechanical determinants of PTA. © 2001 Orthopaedic Research Society. Punlished by Elsevier Science Ltd. All rights reserved.
Lead‐induced developmental changes in AP‐1 DNA binding in rat brain
Authors: Pennypacker Keith R. , Xiao Yang , Xu Ruo H. , Harry G.Jean
Published: July 2002

Exposure to lead during ontogeny is detrimental to the growth and development of the brain. Morphological abnormalities occur in the developing brain, which are manifested as mental retardation and other neurological disorders. Despite extensive research, the biochemical mechanism for neurological effects of lead has not been established but appears to be at the level of the genome since aberrant expression of developmentally‐important genes has been reported. Basal levels of activator protein 1 (AP‐1) transcription factor DNA binding are elevated in the rat brain during the early postnatal period. The AP‐1 DNA binding complex is composed of a Jun:cAMP responsive element binding protein dimer, which appears to modulate expression of developmentally‐important genes that contain AP‐1 binding sites in their promoter. Brain regions from perinatally lead‐exposed rats were examined on postnatal days 3, 9 and 15 for DNA binding activity to the AP‐1 DNA sequence. AP‐1 DNA binding activities were significantly increased on postnatal day 3 in hippocampus and cortex from lead‐treated rats with no other area (frontal lobe or brainstem) or timepoint showing significant changes. Since no increases were detected in the level of Jun protein which is a component of the AP‐1 binding complex, post‐translational modification may be involved in enhancing DNA binding activity. By altering levels of AP‐1 DNA binding to the promoter regions, lead exposure may be changing the levels of mRNA synthesis of developmentally‐important genes.
Laminin expression by glial fibrillary acidic protein positive cells in human gliomas
Authors: Tysnes Berit BØlge , Mahesparan Rupavathana , Thorsen Frits , Haugland Hans Kristian , Porwol Torsten , Enger Per Øyvind , Lund‐Johansen Morten , Bjerkvig Rolf
Published: July 2002

Extracellular matrix components are regarded as important substrates for invasive tumor cells. The present work focuses on the expression of laminin in the brain in response to invading brain tumors. Biopsies obtained from tissue macroscopically evaluated as the border zone between tumor and normal brain, in 5 patients undergoing surgery for glioblastoma multiforme, were examined by immunocytochemistry and scanning confocal microscopy for the expression of laminin and glial fibrillary acidic protein. Laminin was mainly found in all the specimens associated with the basal lamina of blood vessels, but a variable degree of punctate laminin deposits were also observed in the parenchyma not associated with blood vessels. In the specimens with substantial deposits, scanning confocal microscopy showed that some of the laminin co‐localized with intracellular glial fibrillary acidic protein.

Punctate deposits of laminin were also seen in an intracranial BT4C rat glioma model, where it was particularly abundant in the brain/tumor confrontation zone. Previous in vitro studies have shown that laminin, among several extracellular matrix components, represent a highly permissive substrate for glioma cell migration. The presented results indicate that laminin can be produced by glial fibrillary acidic protein positive cells during glioma cell invasion in humans. This glycoprotein may thus represent one important substrate among many, which contribute to the invasive phenotype of gliomas.
Modelling suicide risk in affective disorders
Authors: Boardman A.P. , Healy D.
Published: July 2002

Background

The lifetime risk of suicide in affective disorders is commonly quoted as 15%. This stems from hospital populations of affective disorders.

Aims

To model the lifetime prevalence of suicide using data on completed suicides from one English Health District and community-based rates of prevalence of affective disorders.

Methods

A secondary analysis of a primary data set based on 212 suicides in North Staffordshire was undertaken. The population rates of psychiatric morbidity were obtained from the National Comorbidity Survey.

Results

The model suggests a lifetime prevalence rate of suicide for any affective disorder at 2.4%, with a rate for those uncomplicated by substance abuse, personality disorder or non-affective psychosis at 2.4%, and a rate for uncomplicated cases who had no mental health service contact at 1.1%.

Conclusions

Lifetime prevalence rates of suicide in subgroups of affective disorders may be lower than the traditional rates cited for hospital depression. This has implications for primary care projects designed to investigate the occurrence of and the prevention of suicide.
Measuring quality of life in schizophrenia
Authors: McKenna SP
Published: July 2002

A literature review identified nearly 500 papers in which references to quality of life (QoL) were made in the context of schizophrenia. Despite this, only two studies could be found where efforts had been made to assess the impact of pharmaceutical products on the QoL of patients with schizophrenia. It is argued that lack of progress in this area of research results from the absence of an adequate schizophrenia-specific QoL instrument. The present paper details the requirements for such an instrument, reviews health status instruments that have been used with schizophrenic patients and describes the methodology required for producing a new instrument. It is argued that the pharmaceutical industry should consider joint financing of such development work, given the importance of a reliable, valid and responsive outcome instrument for clinical trials. Such an instrument would also prove valuable when assessing alternative management programmes.
When the lifeboat is overloaded: social support and state enterprise reform in China1
Authors: Chan Kin-man , Qiu Haixiong
Published: July 2002

Based on a survey of ‘off-duty workers’ in Guangzhou, this paper explores the changing structure of social support in China. It focuses on the material aid and guidance in job search received by these workers. It concludes that while the state and its enterprises still play an important role in workers’ economic life, informal social networks have become more pertinent. These social support networks reduce workers’ dependence on the state and provide a social buffer for the transformation of state socialism into market socialism. They also imply a revival of autonomous space in a society that will have more resources to negotiate with the state in the future.
Determinants of planned retirement age
Authors: Montalto Catherine Phillips , Yuh Yoonkyung , Hanna Sherman
Published: July 2002

Determinants of planned retirement age are analyzed. The prediction equation indicates that planned retirement age increases substantially as people get older, and increases somewhat with higher noninvestment income. Social Security reform should recognize that the capacity to continue working and the ability to afford to retire both influence the age at which people plan to retire. The range of planned retirement ages suggests that research on the adequacy of retirement preparation should focus on planned retirement age. Financial planners should consider the finding that planned retirement age increases with age. © 2000 Elsevier Science Inc. All rights reserved.
“Wall street week with Louis Rukheyser” recommendations:Trading activity and performance
Authors: Beltz Jess , Jennings Robert
Published: July 2002

We investigate short‐term volume activity and short‐ and longer‐ term returns associated with recommendations made by regular panelists and special guests on the television show “Wall Street Week with Louis Rukheyser”. In particular, we investigate whether selections made on the show have information content and whether the audience appears to discern differing levels of reliability among recommenders. Overall performance statistics are unimpressive. There are, however, differences in return performance between the recommendations of different individuals, and between favorable and unfavorable recommendations. There is little correlation between the 6‐month performance of a recommendation and the abnormal volume at the date the recommendation is made, suggesting the market cannot discern the more insightful recommendations from the less insightful.
Growth hormone alone or combined with metoprolol preserves cardiac function after myocardial infarction in rats
Authors: Bollano Entela , Bergh Claes‐Håkan , Kjellström Christer , Omerovic Elmir , Kujacic Vuk , Caidahl Kenneth , Bengtsson Bengt‐Åke , Waagstein Finn , Isgaard Jörgen
Published: July 2002

Background and objective:

Beta‐adrenoreceptor blocking agents are important for the treatment of myocardial infarction (MI). Accumulating evidence also indicates that growth hormone (GH) improves cardiac function after MI in rats. We aimed to investigate the cardiovascular effects of combined treatment in an animal model of MI.

Methods:

MI was induced in rats by ligation of the left coronary artery. Three days after MI, animals were randomly assigned to one of four groups: controls (C) (n‐19); GH (n‐19) receiving s.c. 2 mg/kg per day rhGH; metoprolol (M) group (n‐19) receiving 24 mg/kg per day and combined group (GHM) (n‐20) treated with both GH (2 mg/kg per day s.c.) and M (24 mg/kg per day) for 9 days. Transthoracic echocardiography was performed before and after treatment.

Results:

Serum levels of insulin‐like growth factor I were significantly elevated in the GH‐group but not in the GHM group compared to controls. Left ventricular volumes, cardiac index, systolic blood pressure, were similar in all groups. Percent changes in ejection fraction compared to baseline were; GH (6.1±5.0%) and GHM (6.1±4.2%) vs. C (−12.5±3.0%), P<0.01, M (−7.3±4.2%). The occurrence of aneurysms was not significantly different between the various treatment regimes.

Conclusion:

Treatment with growth hormone alone or in combination with metoprolol preserved left ventricular function after MI.
Substrate specificities of inteins investigated by QuickDrop‐cassette mutagenesis
Authors: Oeemig Jesper S. , Beyer Hannes M. , Aranko A. Sesilja , Mutanen Justus , Iwaï Hideo
Published: August 2020

Inteins catalyze self‐excision from host precursor proteins while concomitantly ligating the flanking substrates (exteins) with a peptide bond. Noncatalytic extein residues near the splice junctions, such as the residues at the −1 and +2 positions, often strongly influence the protein‐splicing efficiency. The substrate specificities of inteins have not been studied for many inteins. We developed a convenient mutagenesis platform termed “QuickDrop”‐cassette mutagenesis for investigating the influences of 20 amino acid types at the −1 and +2 positions of different inteins. We elucidated 17 different profiles of the 20 amino acid dependencies across different inteins. The substrate specificities will accelerate our understanding of the structure–function relationship at the splicing junctions for broader applications of inteins in biotechnology and molecular biosciences.
Chirality Transfer from Sub‐Nanometer Biochemical Molecules to Sub‐Micrometer Plasmonic Metastructures: Physiochemical Mechanisms, Biosensing, and Bioimaging Opportunities
Authors: Cao Zhaolong , Gao Han , Qiu Meng , Jin Wei , Deng Shaozhi , Wong Kwok‐Yin , Lei Dangyuan
Published: August 2020

Determining the structural chirality of biomolecules is of vital importance in bioscience and biomedicine. Conventional methods for characterizing molecular chirality, e.g., circular dichroism (CD) spectroscopy, require high‐concentration specimens due to the weak electronic CD signals of biomolecules such as amino acids. Artificially designed chiral plasmonic metastructures exhibit strong intrinsic chirality. However, the significant size mismatch between metastructures and biomolecules makes the former unsuitable for chirality‐recognition‐based molecular discrimination. Fortunately, constructing metallic architectures through molecular self‐assembly allows chirality transfer from sub‐nanometer biomolecules to sub‐micrometer, intrinsically achiral plasmonic metastructures by means of either near‐field interaction or chirality inheritance, resulting in hybrid systems with CD signals orders of magnitude larger than that of pristine biomolecules. This exotic property provides a new means to determine molecular chirality at extremely low concentrations (ideally at the single‐molecule level). Herein, three strategies of chirality transfer from sub‐nanometer biomolecules to sub‐micrometer metallic metastructures are analyzed. The physiochemical mechanisms responsible for chirality transfer are elaborated and new fascinating opportunities for employing plasmonic metastructures in chirality‐based biosensing and bioimaging are outlined.
Enabling High‐Performance Tandem Organic Photovoltaic Cells by Balancing the Front and Rear Subcells
Authors: Cheng Pei , Wang Hao‐Cheng , Zheng Ran , Zhu Yuan , Dai Shuixing , Li Zeyuan , Chen Chung‐Hao , Zhao Yepin , Wang Rui , Meng Dong , Zhu Chenhui , Wei Kung‐Hwa , Zhan Xiaowei , Yang Yang
Published: August 2020

In tandem organic photovoltaics, the front subcell is based on large‐bandgap materials, whereas the case of the rear subcell is more complicated. The rear subcell is generally composed of a narrow‐bandgap acceptor for infrared absorption but a large‐bandgap donor to realize a high open‐circuit voltage. Unfortunately, most of the ultraviolet–visible part of the photons are absorbed by the front subcell; as a result, in the rear subcell, the number of excitons generated on large‐bandgap donors will be reduced significantly. This reduces the (photo) conductivity and finally limits the hole‐transporting property of the rear subcell. In this work, a simple and effective way is proposed to resolve this critical issue. To ensure sufficient photogenerated holes in the rear subcell, a small amount of an infrared‐absorbing polymer donor as a third component is introduced, which provides a second hole‐generation and transporting mechanism to minimize the aforementioned detrimental effects. Finally, the short‐circuit current density of the two‐terminal tandem organic photovoltaic is significantly enhanced from 10.3 to 11.7 mA cm−2 (while retaining the open‐circuit voltage and fill factor) to result in an enhanced power conversion efficiency of 15.1%.
An Efficient Approach to Fabricate Air‐Stable Perovskite Solar Cells via Addition of a Self‐Polymerizing Ionic Liquid
Authors: Xia Rui , Gao Xiao‐Xin , Zhang Yi , Drigo Nikita , Queloz Valentin I. E. , Tirani Farzaneh Fadaei , Scopelliti Rosario , Huang Zhangjun , Fang Xiaodong , Kinge Sachin , Fei Zhaofu , Roldán‐Carmona Cristina , Nazeeruddin Mohammad Khaja , Dyson Paul J.
Published: August 2020

Despite the excellent photovoltaic properties achieved by perovskite solar cells at the laboratory scale, hybrid perovskites decompose in the presence of air, especially at high temperatures and in humid environments. Consequently, high‐efficiency perovskites are usually prepared in dry/inert environments, which are expensive and less convenient for scale‐up purposes. Here, a new approach based on the inclusion of an in situ polymerizable ionic liquid, 1,3‐bis(4‐vinylbenzyl)imidazolium chloride ([bvbim]Cl), is presented, which allows perovskite films to be manufactured under humid environments, additionally leading to a material with improved quality and long‐term stability. The approach, which is transferrable to several perovskite formulations, allows efficiencies as high as 17% for MAPbI3 processed in air % relative humidity (RH) ≥30 (from an initial 15%), and 19.92% for FAMAPbI3 fabricated in %RH ≥50 (from an initial 17%), providing one of the best performances to date under similar conditions.
A Machine‐Fabricated 3D Honeycomb‐Structured Flame‐Retardant Triboelectric Fabric for Fire Escape and Rescue
Authors: Ma Liyun , Wu Ronghui , Liu Sai , Patil Aniruddha , Gong Hao , Yi Jia , Sheng Feifan , Zhang Yuzei , Wang Jiang , Wang Jun , Guo Wenxi , Wang Zhong Lin
Published: August 2020

Fire disaster is one of the most common hazards that threaten public safety and social development: how to improve the fire escape and rescue capacity remains a huge challenge. Here, a 3D honeycomb‐structured woven fabric triboelectric nanogenerator (F‐TENG) based on a flame‐retardant wrapping yarn is developed. The wrapping yarn is fabricated through a continuous hollow spindle fancy twister technology, which is compatible with traditional textile production processes. The resulting 3D F‐TENG can be used in smart carpets as a self‐powered escape and rescue system that can precisely locate the survivor position and point out the escape route to timely assist victim search and rescuing. As interior decoration, the unique design of the honeycomb weaving structure endows the F‐TENG fabric with an excellent noise‐reduction ability. In addition, combining with its good machine washability, air permeability, flame‐retardency, durability, and repeatability features, the 3D F‐TENG may have great potential applications in fire rescue and wearable sensors as well as smart home decoration.
A Cyclometalated Iridium (III) Complex as a Microtubule Probe for Correlative Super‐Resolution Fluorescence and Electron Microscopy
Authors: Tian Xiaohe , De Pace Cesare , Ruiz‐Perez Lorena , Chen Bo , Su Rina , Zhang Mingzhu , Zhang Ruilong , Zhang Qiong , Wang Qin , Zhou Hongping , Wu Jieying , Zhang Zhongping , Tian Yupeng , Battaglia Giuseppe
Published: August 2020

The visualization of microtubules by combining optical and electron microscopy techniques provides valuable information to understand correlated intracellular activities. However, the lack of appropriate probes to bridge both microscopic resolutions restricts the areas and structures that can be comprehended within such highly assembled structures. Here, a versatile cyclometalated iridium (III) complex is designed that achieves synchronous fluorescence–electron microscopy correlation. The selective insertion of the probe into a microtubule triggers remarkable fluorescence enhancement and promising electron contrast. The long‐life, highly photostable probe allows live‐cell super‐resolution imaging of tubulin localization and motion with a resolution of ≈30 nm. Furthermore, correlative light–electron microscopy and energy‐filtered transmission electron microscopy reveal the well‐associated optical and electron signal at a high specificity, with an interspace of ≈41 Å of microtubule monomer in cells.
Fabrication of CdS Frame‐in‐Cage Particles for Efficient Photocatalytic Hydrogen Generation under Visible‐Light Irradiation
Authors: Zhang Peng , Luan Deyan , Lou Xiong Wen (David)
Published: August 2020

The design of advanced structures for semiconductor photocatalysts is an effective approach to enhance their performance toward solar‐to‐chemical energy conversion. Hollow and frame‐like structures show advantageous features for photocatalytic reactions with enlarged surface area, shortened charge‐transfer distance, promoted light‐absorption ability, and enhanced mass‐transfer capability. Here, a facile two‐step sulfidation strategy is developed to fabricate unique CdS frame‐in‐cage particles for photocatalytic hydrogen generation. Cd‐based Prussian blue analog (Cd‐PBA) cubes are first converted to Cd‐PBA cube‐in‐CdS cage particles, which are further transformed to CdS frame‐in‐cage particles. Benefiting from the novel frame‐in‐cage structure, the obtained CdS photocatalyst exhibits high activity under visible‐light irradiation with the hydrogen generation rate of 13.6 mmol h−1 g−1, which is much enhanced compared with those of the CdS cubes and cages.
Boosting the Performance of Nitrogen‐Doped Mesoporous Carbon Oxygen Electrode with Ultrathin 2D Iron/Cobalt Selenides
Authors: Hong Xuekun , Xu Yuyang , Wang Ruyue , Du Peng , Zhao Zebi , Huang Kai , Tang Haolin , Liu Yushen , Lei Ming , Wu Hui
Published: August 2020

High‐performance and low‐cost oxygen electrode catalysts for rechargeable metal–air battery have been regarded as one pivotal issue for the ever‐increasing energy‐demanding devices like electric vehicles, domestic appliances, and consumer electronics. To develop an effective substitute of noble‐metal‐based catalysts, the modified nitrogen‐doped mesoporous carbon (NMC) is proposed as composite catalysts with a series of 2D transition metal selenides (MSe, M = Fe and/or Co) by liquid exfoliation, anchoring, and thermal activation. By varying the transition metal elements, CoSe@NMC is confirmed as the competitive alternative relative to the coupled commercial catalysts (IrO2 and Pt/C), with a comparable overpotential for oxygen evolution reaction at 10 mA cm−2 and positively shifted half‐wave potential for oxygen reduction reaction even after accelerated durability tests for 5000 cycles. Therefore, this postmodification strategy can promote further design toward the advanced electrode materials for other energy conversion and storage techniques.
Perovskite Emitters as a Platform Material for Down‐Conversion Applications
Authors: Lee Hyeokjae , Park Jinwoo , Kim Sungjin , Lee Seung‐Chul , Kim Young‐Hoon , Lee Tae‐Woo
Published: August 2020

Methods to overcome the instability of perovskites to moisture, light, and heat in down‐converted displays (DCDs), in which films of perovskite emitters are placed on top of the backlight unit and convert its light to a desired color, are reviewed here. First, the photophysical properties of perovskite emitters as light converters in DCDs are discussed. Second, five strategies to improve stability of perovskite emitting materials (PeMs) mostly in a form of perovskite nanoparticles (PeNPs) are summarized: i) encapsulation in inorganics, ii) encapsulation in polymer, iii) semiconductor shelling, iv) ligand engineering, and v) defect engineering. Third, examples of DCDs that use perovskite emitters are presented. Finally, future perspectives for the commercialization of perovskite emitters as a next‐generation material that can be applied to DCDs are outlined.