bluuebunny/crossref_metadata_2025 huggingface dataset:
Inorganic anions induce state changes in spinach thylakoid membranes
Authors: Jajoo Anjana , Bharti Sudhakar , Govindjee
Published: July 2002

The role of cations in excitation energy distribution between the two photosystems of photosynthesis is well established. This paper provides evidence, for the first time, for an important role of anions in the regulation of distribution of absorbed light energy between the two photosystems. Inorganic anions caused redistribution of energy more in favour of photosystem I, as judged from measurements of chlorophyll a fluorescence transients, rates of electron transport in low light and 77 K fluorescence emission spectra: the Fv/Fm ratio was decreased by inorganic anions even in the presence of DCMU, the PS II electron transport was decreased whereas PS I electron transport was increased and the F735 (77 K emission from PS I)/F685 (77 K emission from PS II) ratio was increased. Such changes were observed with inorganic anions having different valencies (Cl−, SO2−
4, PO3−
4): the higher the valency of the inorganic anion, the more the energy transferred towards PS I. Change in the valency of the inorganic anions thus regulates distribution of absorbed light energy between the two photosystems. However, organic anions like acetate, succinate, and citrate caused no significant changes in the Fv/Fm ratio, and in rates of PS I and PS II electron transport, showing their ineffectiveness in regulating light energy distribution.
TNF‐α converting enzyme (TACE) is inhibited by TIMP‐3
Authors: Amour Augustin , Slocombe Patrick M , Webster Ailsa , Butler Michael , Knight C.Graham , Smith Bryan J , Stephens Paul E , Shelley Chris , Hutton Mike , Knäuper Vera , Docherty Andrew J.P , Murphy Gillian
Published: July 2002

TNF‐α converting enzyme (TACE; ADAM‐17) is a membrane‐bound disintegrin metalloproteinase that processes the membrane‐associated cytokine proTNF‐α to a soluble form. Because of its putative involvement in inflammatory diseases, TACE represents a significant target for the design of specific synthetic inhibitors as therapeutic agents. In order to study its inhibition by tissue inhibitors of metalloproteinases (TIMPs) and synthetic inhibitors of metalloproteinases, the catalytic domain of mouse TACE (rTACE) was overexpressed as a soluble Ig fusion protein from NS0 cells. rTACE was found to be well inhibited by peptide hydroxamate inhibitors as well as by TIMP‐3 but not by TIMP‐1, ‐2 and ‐4. These results suggest that TIMP‐3, unlike the other TIMPs, may be important in the modulation of pathological events in which TNF‐α secretion is involved.
Synergistic upregulation of metalloproteinase‐9 by growth factors and inflammatory cytokines: an absolute requirement for transcription factor NF‐κB
Authors: Bond Mark , Fabunmi Rosalind P , Baker Andrew H , Newby Andrew C
Published: July 2002

Matrix metalloproteinase (MMPs) enzymes are implicated in matrix remodelling during proliferative inflammatory processes including wound healing. We report here synergistic upregulation of MMP‐9 protein and mRNA by platelet‐derived growth factor (PDGF) or basic fibroblast growth factor (bFGF) in combination with interleukin‐1α (IL‐1α) or tumour necrosis factor‐α (TNF‐α) in primary rabbit and human dermal fibroblasts. The synergistic interaction between growth factors and cytokines implies that basement membrane remodelling is maximal physiologically when both are present together. The signalling pathways mediating this synergistic regulation are not understood, although analysis of the MMP‐9 promoter has identified an essential proximal AP‐1 element and an upstream nuclear factor kappa‐B (NF‐κB) site. Using electromobility shift assays, binding to the AP‐1 site was only slightly increased by growth factors and cytokines. NF‐κB binding was rapidly induced by IL‐1α or TNF‐α but was neither induced nor potentiated by bFGF or PDGF. Neither AP‐1 nor NF‐κB was therefore sufficient on its own for synergistic regulation. Using a recently developed adenovirus that overexpresses the inhibitory subunit, IκBα, we demonstrated an absolute requirement for NF‐κB in upregulation of MMP‐9. Activation of NF‐κB binding by inflammatory cytokines was therefore necessary but not sufficient for synergistic upregulation of MMP‐9.
Activation of caspase‐3‐like protease by digitonin‐treated lysosomes
Authors: Ishisaka Rumi , Utsumi Toshihiko , Yabuki Munehisa , Kanno Tomoko , Furuno Takashi , Inoue Masayasu , Utsumi Kozo
Published: July 2002

Apoptosis, a naturally occurring programmed cell death or cell ‘suicide’, has been paid much attention as one of the critical mechanisms for morphogenesis and tissue remodeling. Activation of cysteine aspartases (caspases) is one of the critical steps leading to apoptosis. Although a mitochondria‐mediated pathway has been postulated to be one of the activation mechanism of caspase‐3, another subcellular compartment might be involved in the activation of the enzyme. The present study shows that the supernatant fraction of digitonin‐treated lysosomes strongly activates Ac‐DEVD‐CHO inhibitable caspase‐3‐like protease. Activation of caspase‐3‐like protease by digitonin‐treated lysosomal fractions was specifically suppressed by leupeptin and E‐64, inhibitors of cysteine protease. These results indicate that leakage of lysosomal cysteine protease(s) into the cytosolic compartment might be involved in the activation of caspase‐3‐like protease.
Microsome‐mediated transformation of O‐methylandrocymbine to demecolcine and colchicine
Authors: Rueffer Martina , Zenk Meinhart H
Published: July 2002

Microsomal preparations from immature seeds of Colchicum autumnale L. catalyse the ring expansion reaction of O‐methylandrocymbine to demecolcine in the presence of NADPH and O2. In addition evidence is given for further transformation of demecolcine to colchicine in the presence of acetyl‐CoA and NADPH.
Studies on the binding of wheat germ agglutinin (Triticum vulgaris) to O‐glycans
Authors: Wu Albert M. , Wu June H. , Song Shuh-Chyung , Tsai Ming-Sung , Herp Anthony
Published: July 2002

The binding profile of Triticum vulgaris (WGA, wheat germ) agglutinin to 23 O‐glycans (GalNAcα1→Ser/Thr containing glycoproteins, GPs) was quantitated by the precipitin assay and its specific interactions with O‐glycans were confirmed by the precipitin inhibition assay. Of the 28 glycoforms tested, six complex O‐glycans (hog gastric mucins, one human blood group A active and two precursor cyst GPs) reacted strongly with WGA and completely precipitated the lectin added. All of the other human blood group A active O‐glycans and human blood group precursor GPs also reacted well with the lectin and precipitated over two‐thirds of the agglutinin used. They reacted 4–50 times stronger than N‐glycans (asialo‐fetuin and asialo‐human α1 acid GP). The binding of WGA to O‐glycans was inhibited by either p‐NO2‐phenyl α,βGlcNAc or GalNAc. From these results, it is highly possible that cluster (multivalent) effects through the high density of weak inhibitory determinants on glycans, such as GalNAcα1→Ser/Thr (Tn), GalNAc at the non‐reducing terminal, GlcNAcβ1→ at the non‐reducing end and/or as an internal residue, play important roles in precipitation, while the GlcNAcβ1→4GlcNAc disaccharide may play a minor role in the precipitation of mammalian glycan‐WGA complexes.
Unequal cross‐over is involved in human alpha satellite DNA rearrangements on a border of the satellite domain
Authors: Mashkova Tamara , Oparina Nina , Alexandrov Ivan , Zinovieva Olga , Marusina Alina , Yurov Yuri , Lacroix Marie-Helene , Kisselev Lev
Published: July 2002

It can be invoked from the theory of tandem repeat homogenization that DNA on a satellite/non‐satellite border may carry sequence marks of molecular processes basic to satellite evolution. We have sequenced a continuous 17‐kb alpha satellite fragment bordering the non‐satellite in human chromosome 21, which is devoid of higher‐order repeated structure, contains multiple rearrangements, and exhibits higher divergence of monomers towards the border, indicating the lack of efficient homogenization. Remarkably, monomers have been found with mutually supplementary deletions matching each other as reciprocal products of unequal recombination, which provide evidence for unequal cross‐over as a mechanism generating deletions in satellite DNA.
Generation of hydrogen peroxide precedes loss of mitochondrial membrane potential during DNA alkylation‐induced apoptosis
Authors: Tada-Oikawa Saeko , Oikawa Shinji , Kawanishi Michiko , Yamada Michiyuki , Kawanishi Shosuke
Published: July 2002

Pulsed field gel electrophoresis showed that the initiation time of DNA breakage induced by the DNA alkylating agent duocarmycin A, which is not a redox‐cycling agent, was almost the same in the human leukemia cell line HL‐60 and its H2O2‐resistant clone HP100. Catalase activity of HP100 cells was much higher than that of HL‐60 cells. Duocarmycin A‐mediated DNA ladder formation in HP100 cells was delayed compared with that in HL‐60 cells, suggesting the involvement of H2O2 in duocarmycin A‐induced apoptosis. Flow cytometry demonstrated that peroxide formation preceded loss of mitochondrial membrane potential (ΔΨm) in cells treated with duocarmycin A. Then, caspase‐3 was activated, followed by DNA ladder formation. These findings suggest that DNA damage by duocarmycin A induces H2O2 generation, which causes ΔΨm loss and subsequently caspase‐3 activation, resulting in apoptosis.
Dermal fibroblast proliferation is improved by β‐catenin overexpression and inhibited by E‐cadherin expression
Authors: Soler C. , Grangeasse C. , Baggetto L.G. , Damour O.
Published: July 2002

Several recent studies have shown that proteins of the cadherin‐catenin complex are not only involved in cell‐cell adhesion but also in the proliferation and differentiation processes. For the first time, we investigated the effect of the quantity of cytoplasmic β‐catenin on dermal fibroblast proliferation by overexpressing human β‐catenin in human dermal fibroblasts. Our results show that dermal fibroblasts overexpressing normal β‐catenin or a stabilized β‐catenin mutant have a higher growth rate than control fibroblasts. Moreover, when confluence is reached, the number of fibroblasts is increased when the cells overexpress β‐catenin suggesting a role for β‐catenin in the regulation of contact growth arrest. Finally, by comparing proliferation in normal dermal fibroblasts and dermal fibroblasts expressing E‐cadherin we observed a negative regulatory effect of E‐cadherin expression on fibroblast proliferation. These data demonstrate the involvement of β‐catenin and cadherin in the dermal fibroblast proliferation process and in contact growth arrest.
Concatemerization of tRNA molecules in the presence of trivaline derivative
Authors: Streltsov Sergey A. , Martinkina Larissa P. , Vengerov Yuri Yu.
Published: July 2002

The interaction of tRNA with trivaline dansyl hydrazide trifluoroacetate (DHTV) has been studied. The shape of curves of fluorimetric titration of tRNA with DHTV and vice versa can be explained only by formation of DHTV dimers on tRNA molecules, and subsequent association of DHTV‐saturated tRNA molecules with each other. The ability of tRNA molecules to form concatemers in solution in the presence of DHTV has been demonstrated by electron microscopy. Electron microscopy of the tRNA‐DHTV complexes stained with uranyl acetate revealed flexible rods 6–7 nm thick and up to several micrometers long.
Phosphatidylinositol 3′‐kinase and tyrosine‐phosphatase activation positively modulate Convulxin‐induced platelet activation. Comparison with collagen
Authors: Lagrue Anne-Helène , Francischetti Ivo M.B. , Guimarães Jorge A. , Jandrot-Perrus Martine
Published: July 2002

In this report we have studied the role of phosphatidylinositol 3′‐kinase (PI3‐K) and tyrosine phosphatase activation on platelet activation by Convulxin (Cvx). Wortmannin, a specific PI3‐K inhibitor, and phenylarsine oxide (PAO), a sulfhydryl reagent that inhibits tyrosine phosphatase (PTPase), block Cvx‐induced platelet aggregation, granule secretion, inositol phosphate production, and increase in [Ca2+]i. However, PAO does not inhibit Cvx‐induced tyrosine phosphorylation of platelet proteins, including Syk and PLCγ2, but blocked collagen‐induced platelet aggregation as well as tyrosine phosphorylation of PLCγ2. In contrast, Cvx‐induced PLCγ2 tyrosyl phosphorylation was partially inhibited by wortmannin. We conclude that (i) although Cvx and collagen activate platelets by a similar mechanism, different regulatory processes are specific to each agonist; (ii) mechanisms other than tyrosine phosphorylation regulate PLCγ2 activity; and (iii) besides protein tyrosine kinases, PI3‐K (and PTPase) positively modulate platelet activation by both Cvx and collagen, and this enzyme is required for effective transmission of GPVI‐Fc receptor γ chain signal to result in full activation and tyrosine phosphorylation of PLCγ2 in Cvx‐stimulated platelets.
Polymeric IgA are sulfated proteins
Authors: Boisgard Raphaël , Charpigny Gilles , Chanat Eric
Published: July 2002

The main sulfated proteins secreted by rabbit mammary gland tissue had M
r of ∼67 000, 63 000 and 23 000, and one component which most likely corresponded to proteoglycans had a diffuse electrophoretic mobility (M
r>200 000). The sulfate groups in the 67–63 kDa proteins were mostly linked to carbohydrates. These proteins and the 23 kDa protein were co‐purified and identified to heavy chains of immunoglobulin A (IgA) and J chain, respectively. Sulfation of α‐chains also occurred in rat mammary and rabbit lacrimal glands. We conclude that polymeric IgA which are produced by plasma cells and released in secretion fluids after transcytosis through epithelia are sulfated.
C‐reactive protein and the treatment of pelvic inflammatory disease
Authors: Reljič M , Gorišek B
Published: July 2002

Objective: The significance of C‐reactive protein (CRP) in assessing the treatment of pelvic inflammatory disease (PID) was established and compared with body temperature (BT), erythrocyte sedimentation rate (ESR) and serum leukocyte concentration (L). Method: In 51 patients with PID, 20 (39%) of them with tubo‐ovarial abscess (TOA), measurement of BT and laboratory investigations were carried out on admission and during treatment on days 3–4, 6–8 and 18–21. The changes in these values were compared with the changes in clinical condition. Result: Prior to treatment, the majority — 49 patients or 96.1% — had increased CRP values. In successful treatment, the CRP values decreased significantly in PID patients without TOA on day 3–4, in patients with TOA on day 6–8 and reached normal values in both groups on day 18–21. Changes in clinical condition were most concurrent with changes in CRP. Conclusion: In assessing PID treatment, the determination of CRP has precedence over L, ESR and BT as the percentage of patients with increased CRP is higher and because the changes in value follow the changes in clinical condition more reliably.
Calcium‐phosphorus‐magnesium homeostasis in women with threatened preterm delivery
Authors: Smolarczyk R. , Wójcicka‐Jagodzińska J. , Romejko E. , Piekarski P. , Czajkowski K. , Teliga J.
Published: July 2002

Objective: The effect of threatened preterm delivery on calcium, phosphorus, magnesium homeostasis in the third trimester of pregnancy was investigated. Methods: Serum concentrations of total and ionized calcium, inorganic phosphorus, magnesium, total protein, albumin, total estrogens and human placental lactogen were determined in women with threatened preterm delivery at 29–36 weeks of gestation (the studied group) and in women with uncomplicated pregnancy of the same duration (the control group). Additionally, activities of total alkaline phosphatase and heat‐stable alkaline phosphatase fraction were measured. Results: Patients of the studied group compared to the control group showed decreased concentration of total calcium (2.17 ± 0.09 vs. 2.28 ± 0.13 mmol/l, P < 0.0005), inorganic phosphorus (1.13 ± 0.27 vs. 1.32 ± 0.23 mmol/l, P < 0.001) and magnesium (0.64 ± 0.07 vs. 0.70 ± 0.10 mmol/l, P < 0.003); they also demonstrated decreased activity of total alkaline phosphatase (70.8 ± 23.2 vs. 81.9 ± 14.9 IU/l, P < 0.01) and its heat‐stable fraction (30.2 ± 15.6 vs. 59.6 ± 14.9 IU/l, P < 0.001). In the studied group no difference was found in concentrations of investigated ions and enzymes between women who delivered at term and women who delivered prematurely. Patients with threatened preterm delivery showed serum deficiency of total calcium, phosphorus and magnesium which might be related to premature uterine contractility but does not predict premature labor by week 36 of gestation (66% of patients delivered at term). Conclusion: The deficiency of minerals and lowered activity of total alkaline phosphatase is observed in women with threatened preterm delivery. Laboratory tests of calcium‐phosphorus‐magnesium homeostatsis have limited predictive value in regard to the term of delivery in women with threatened preterm delivery.
Manufacturing technology and strategy formulation: keys to enhancing competitiveness and improving performance
Authors: Tracey Michael , Vonderembse Mark A , Lim Jeen‐Su
Published: July 2002

Porter [Porter, M.E., 1996. What is strategy? Harvard Business Review 74 (6), 61–78.] claims that a proper link between strategy and manufacturing operations is a key to developing sustainable competitive advantage. To be successful in this globally competitive, rapidly changing environment, organizations must formulate strategic plans that are consistent with their investment in and use of manufacturing technology. This study proposes that organizations that invest in advanced manufacturing technology and develop mechanisms for manufacturing managers to participate in strategy formulation will have improved competitive capabilities and better performance than firms that do not. Using the result from a large‐sample survey, this study develops valid and reliable measures of advanced manufacturing technology and manufacturing managers' participation in strategy formulation as well as the competitive capabilities of a firm. Linear structural equation analysis (LISREL) results show that the relationships between a firm's practices in these two areas and its competitive capabilities are found to be statistically significant and positive. Also, high levels of these competitive capabilities lead to high levels of performance as measured by customer satisfaction and marketing performance.
Quantitative variation in vascular endothelial growth factor mRNA expression during early flexor tendon healing: an investigation in a canine model
Authors: Boyer Martin I. , Watson Jeffry T. , Lou Jueren , Manske Paul R. , Gelberman Richard H. , Cai Shi Rong
Published: July 2002

Vascular endothelial growth factor (VEGF) is a potent mediator of angiogenesis, with direct mitogenic activity on cells of endothelial origin. We quantified the temporal accumulation of VEGF mRNA at the repair site of an in vivo canine intrasynovial flexor tendon repair and rehabilitation model by means of quantitative Northern blot analysis, in order to detail a molecular signal involved in the intrinsic angiogenic process that accompanies early flexor tendon healing. Significant accumulation of VEGF mRNA occurred at the flexor tendon repair site at 7 days post‐operatively, with peak levels seen at post‐operative days 7 and 10. Levels returned to baseline by day 14.

Local VEGF mRNA accumulation at the repair site temporally precedes and is spatially distinct from the vascular ingrowth itself, which has been shown to occur maximally at day 17. These data suggest that cells within the flexor tendon repair site are involved in molecular processes other than the synthesis of extracellular matrix, such as modulation of angiogenesis. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Isolation of neuronal precursors from differentiating P19 embryonal carcinoma cells by neuronal Tα1‐promoter‐driven GFP
Authors: Kim Joon , Choi Seung Cheol , Kim Tae Hyung , Kim Ki Dong , Cho Si Young , Park Sung Soo , Lee Sang Ho
Published: July 2002

The induction of pluripotent P19 embryonal carcinoma (EC) cells with retinoic acid results in their differentiation into cells that resemble neurons, glia, and fibroblasts. To isolate and enrich the developing neurons from heterogeneously differentiating P19 EC cells, we used a recently introduced protocol combining the expression of green fluorescent protein (GFP) driven by a tissue‐specific promoter and fluorescence‐activated cell sorting. Cells were transfected with the gene for GFP, which is under the control of the neuronal Tα1 tubulin promoter. After four days of retinoic acid treatment, GFP was specifically detected in cells undergoing neuronal differentiation. Sorting of fluorescent differentiating P19 EC transfectants yielded populations highly enriched in neuronal precursors and neurons. Immunoreactivity for nestin and neurofilament was observed in 80 and 25% of the sorted cell population, respectively. These results demonstrate that differentiated neuronal precursor cells can be efficiently isolated from differentiating pluripotent embryonic cells in vitro, suggesting that this method can reproducibly provide homogeneous materials for further studies on neurogenesis.
Correlation of in vitro anti‐proliferative potential with in vivo teratogenicity in a series of valproate analogues
Authors: Courage‐Maguire Carol , Bacon Christopher L. , Nau Heinz , Regan Ciaran M.
Published: July 2002

The prediction that an anti‐proliferative effect coupled with a pro‐differentiative action will detect a neural tube teratogen has been validated by comparison of these in vitro endpoints with in vivo teratogenicity in a series of closely allied valproate structural analogues. The majority of the compounds significantly inhibited C6 glioma proliferation, the most potent compounds being ranked as octanoic acid >2‐propylhexanoic acid≥2‐ethylhexanoic acid≥valproic acid. The anti‐proliferative potency of these compounds did not correlate strictly to their relative in vivo teratogenic potential. Valproic acid exhibited an anti‐proliferative ic50 of 1.45 mM, whereas 2‐propyl‐2‐pentenoic acid and 2‐propyl‐4‐pentenoic acid were virtually indistinguishable, exhibiting significantly lower ic50 values of 2.5 and 2.55 mM, respectively. The concanavalin A lectin affinity assay was employed to establish whether an anti‐proliferative action was coupled with an increased state of cell differentiation. In this lectin affinity assay, the most potent analogues to significantly attenuate the affinity of exposed C6 glioma cells for concanavalin A lectin‐coated plastic included 2‐butylhexanoic acid, 2‐propyl‐4‐pentenoic acid, 2‐propylhexanoic acid and 2‐ethylhexanoic acid in a manner which can be related to their relative teratogenic potencies in vivo. All compounds screened positive in both the anti‐proliferative and pro‐differentiative assays exhibited in vivo exencephalic rates of 5–44%. These included valproic acid, 2‐ethylhexanoic acid, 2‐propylhexanoic acid and 2‐butylhexanoic acid. It would appear that combined anti‐proliferative and pro‐differentiative screens provide a promising detection system for teratogenic status in a series of valproate analogues.
Immortalized cell lines from embryonic avian and murine otocysts: Tools for molecular studies of the developing inner ear
Authors: Barald K.F. , Lindberg K.H. , Hardiman K. , Kavka A.I. , Lewis J.E. , Victor J.C. , Gardner C.A. , Poniatowski A.
Published: July 2002

Recently, our studies have focused on genes expressed at the earliest stages of inner ear development. Our aim is to identify and characterize genes that are involved in determining the axes of the semicircular canals, in otic crest delamination and in early innervation of the inner ear. Many elegant studies of auditory development have been done in animal models. However, the need for large amounts of well‐characterized embryonic material for molecular studies makes the development of otocyst cell lines with different genetic repertoires attractive. We have therefore derived immortalized otocyst cells from two of the most widely used animal models of ear development: avians and mice. Avian cell isolates were produced from quail otocysts (embryonic stage 19) that were transformed with temperature‐sensitive variants of the Rous sarcoma virus (RSV). Among the individual transformed cells are those that produce neuron‐like derivatives in response to treatment with 10−9 M retinoic acid. Mammalian cell isolates were derived from otocysts, of 9 day (post coitus) embryos of the H2kbtsA58 transgennc mouse (Immortomouse), which carries a temperature‐sensitive variant of the Simian Virus 40 Tumor antigen. The vast majority of cells of the Immortomouse are capable of being immortalized at 33°C, the permissive temperature for transgene expression, in the presence of γterferon. Several putative clones of these cells differentiated into neuron‐like cells after temperature shift and withdrawal of γ‐interferon; another isolate of cells assumed a neuron‐like morphology on exposure to brain‐derived neurotrophic factor even at the permissive temperature. We describe also a cell isolate that expresses the Pax‐2 protein product and two putative cell lines that express the protein product of the chicken equivalent of the Drosophila segmentation gene engrailed. These genes and their protein products are expressed in specific subpopulations of otocyst cells at early stages. Both mouse and quail immortalized cell lines will be used to study inner ear development at the molecular level.
In Vitro pattern formation during neurogenesis in neuroectodermal progenitor cells immortalized by p53‐deficiency
Authors: Schlett Katalin , Herberth Balázs , Madarász Emilia
Published: July 2002

In vitro neural differentiation was induced in a p53‐deficient immortalized neuroectodermal progenitor cell line, NE‐4C, by treatment with retinoic acid [K. Schlett and E. Madarász (1997) J. Neurosci. Res.47, 405–416]. Rearrangement of nestin filaments was an early marker of neuron‐formation. The increase in neurofilament protein content was accompanied by a decrease in the expression of nestin filaments in induced precursors. Cells with astroglial features appeared with a delay of 4–5 days compared to the appearence of neurons.

Future neurons were sorted out from the substrate‐attached population of apparently non‐induced cells. The sorting out of future neurons resembled the separation of neural precursorsin vivo. The continuous changes in the shape and also in the position of the cells resulted in the formation of characteristic morphological patterns. On the basis of morphological changes, five characteristic stages of in vitro neural differentiation were distinguished.

The analysis of the morphological changes revealed that cell‐to‐cell interactions played an essential role in the cell fate decision made by induced precursors. Our observations indicate that the NE‐4C cell line can serve as an in vitro model to investigate some early steps of neurogenesis.
China: alternative futures
Authors: Clemens Walter C.
Published: July 2002

What alternatives are available to China in the next one or two decades? ‘More of the same’ is not a likely scenario, because one-party rule is not optimal for coping with the challenges of modernization and global interdependence. A second model, Singapore's authoritarian capitalism, appeals to many CCP leaders. But Singapore's scale and way of life are so different that its example cannot be very relevant to China. Nor does the Soviet imperial model fit, because China does not suffer from imperial overreach as did the USSR. The post-Soviet Russian model—a move from rigid hierarchy to free enterprise anarchy—could await China. Both countries have lacked institutions of civil society that could stabilize the country if central authority collapses. Another alterative would be a return to regionalism, spurred by economic and ethnic differences within China. Some PRC leaders hope to find a Chinese way that transcends other models, but this is not realistic. The most useful model for China and the world would be a gradual transition from authoritarianism to multi-party democracy, as has taken place in Taiwan. In one or two decades, China could edge in that direction. If so, animosities between the mainland and Taiwan would also diminish, removing a thorn from U.S.–Chinese relations. Opportunities for mutual gain may then overshadow present tensions.
Breath isoprene in patients with heart failure
Authors: Lawrence T. McGrath , Robin Patrick , Bernard Silke
Published: July 2002

Background:

Chronic heart failure (CHF) is characterised by increased vascular resistance. This increased after load on the left ventricle contributes to the vicious cycle that leads to progression of myocardial failure, multiple organ failure and death. There is evidence for increased oxidative stress in heart failure, which will influence the myocardium but also peripheral vasculature endothelium.

Aims:

The aim of the present study was to examine the production of isoprene, reputed to reflect oxidative stress, in patients with CHF compared to control subjects.

Methods:

Twelve patients with CHF and thirty‐one healthy control subjects free from heart disease were studied. Breath was collected via a two‐way non‐re‐breathing valve into a 60‐l gas collection bag. A sample of ambient air was collected at the same time. A measured aliquot of patient breath and ambient air (approx. 1.5 l) was adsorbed onto a gas adsorption tube packed with poropak‐Q. Isoprene was measured using GC/MS and the production rate calculated. All samples of breath were collected at 10.00 h after subjects had been sitting at rest for 15 min.

Results:

Breath isoprene production in subjects with CHF was significantly reduced compared to controls 83(23) vs. 168(20) pmol min−1 kg−1.

Conclusion:

Breath isoprene does not directly reflect oxidative stress in CHF.
THE LIVED PREGNANCY EXPERIENCE OF WOMEN IN PRISON
Authors: Wismont Judith Merenda
Published: July 2002

The professional literature reflects limited awareness of and/or concern for the effects of incarceration on the physical and psychological dimensions of childbearing. The purpose of this study was to describe the childbearing experience as reported by pregnant incarcerated women. Giorgi's phenomenological method was used. Apprehension, grief, subjugation, and relatedness were the essential themes related to the experience of childbearing in prison which emerged from the analysis of the transcripts of the journal entries and interview data. Incarceration was the fulcrum on which the women's pregnancy experiences balanced.

Rapidly rising numbers of women imprisoned in the United States underscore the urgency to better understand their experiences. Health care providers must find ways to help female inmates cope more effectively with the role diffusion/confusion they experience as they live two diametrically opposing roles—those of inmate and mother. Correctional facilities must also be assisted in establishing policies that recognize the unique needs of pregnant incarcerated women.
Herbicide effects on the establishment of a native bunchgrass in annual grass invaded areas: Indaziflam versus imazapic
Authors: Terry Tyson J. , Madsen Matthew D. , Gill Richard A. , Anderson Val Jo , St. Clair Samuel B.
Published: March 2021

1. Annual grass invasion is transforming the western United States and driving a need for restoration techniques that can both reduce exotic annual grass abundance and allow revegetation of native species. Pre‐emergent herbicides can provide control of annual grasses, but when applied concurrently with direct seeding efforts, the herbicide can also impact seeded species. Indaziflam is a relatively new herbicide that may provide extended control of exotic annual grasses, but little is known about its effects when applied at the time of seeding.

2. In this study, we compared indaziflam to imazapic, a popular herbicide used in restoration efforts, to understand how indaziflam affects plant establishment of a native species, bluebunch wheatgrass Pseudoroegneria spicata (Pursh) Á. Löve. We created furrows on half our treatments to limit herbicide concentrations and potentially create a safe‐site for seeding bluebunch wheatgrass.

3. During the 2‐year study, indaziflam provided consistent control of the annual weed, downy brome Bromus tectorum L., whereas imazapic control decreased sharply with time. Indaziflam and imazapic decreased bluebunch wheatgrass seedling emergence by 96% and 46%, and 2‐year plant density by 91% and 65%, respectively, compared to non‐herbicide treatments. Both herbicides reduced aboveground biomass of bluebunch wheatgrass by over 85% 2 years after seeding/herbicide application.

4. Furrow treatments mitigated imazapic's effect on bluebunch wheatgrass, but did not limit the impacts by indaziflam.

5. Herbicide can be used in conjunction with direct seeding efforts, but mitigation of the effects to native seeds will depend on herbicide specifics such as mode of action and soil mobility.
Using macroecological species distribution models to estimate changes in the suitability of sites for threatened species reintroduction
Authors: Bellis Joe , Longden Mike , Styles Joshua , Dalrymple Sarah
Published: March 2021

1. Species reintroductions often aim to establish populations of threatened taxa over the long‐term. However, climate change may jeopardize reintroduction efforts by altering the conditions of a recipient site beyond the tolerances of the focal species. To aid the selection of recipient sites that will retain their suitability under climate change, species distribution models (SDMs) have been proposed as a method of locating areas with a greater likelihood of facilitating species persistence.

2. We applied SDMs to predict macroclimatic suitability changes for 13 threatened plant and invertebrate species considered for reintroduction at four lowland raised bog sites undergoing restoration. We estimated suitability based on current and projected future conditions under two greenhouse gas concentration scenarios – one low (RCP2.6) and one high (RCP8.5) – using three general circulation models, for the period 2041–2060.

3. When considering current predicted suitability, our models indicated that nine species were viable candidates for reintroduction to at least one of the restoration sites. But when accounting for potential future changes in suitability, the number of candidates was reduced to seven species, based on the RCP8.5 climate change scenario. While three of the sites received consistently similar predictions of suitability across species and scenarios, the most northerly site, Red Moss, received divergent suitability predictions for some species. This site is predicted to remain suitable forMetrioptera brachypteraandGenista anglicaunder at least one scenario despite substantial losses forecast across the rest of their U.K. ranges, suggesting that it could act as a macroclimatic refuge as climate change advances.

4. The findings presented here made a valuable contribution to the reintroduction planning process, by facilitating the prioritization of reintroduction efforts towards species with a greater likelihood of establishing long‐term populations at the prospective recipient sites.
3D Porous Oxidation‐Resistant MXene/Graphene Architectures Induced by In Situ Zinc Template toward High‐Performance Supercapacitors
Authors: Yang Xue , Wang Qian , Zhu Kai , Ye Ke , Wang Guiling , Cao Dianxue , Yan Jun
Published: March 2021

2D MXene materials have attracted intensive attention in energy storage application. However, MXene usually undergoes serious face‐to‐face restacking and inferior stability, significantly preventing its further commercial application. Herein, to suppress the oxidation and self‐restacking of MXene, an efficient and fast self‐assembly route to prepare a 3D porous oxidation‐resistant MXene/graphene (PMG) composite with the assistance of an in situ sacrificial metallic zinc template is demonstrated. The self‐assembled 3D porous architecture can effectively prevent the oxidation of MXene layers with no evident variation in electrical conductivity in air at room temperature after two months, guaranteeing outstanding electrical conductivity and abundant electrochemical active sites accessible to electrolyte ions. Consequently, the PMG‐5 electrode possesses a striking specific capacitance of 393 F g−1, superb rate performance (32.7% at 10 V s−1), and outstanding cycling stability. Furthermore, the as‐assembled asymmetric supercapacitor possesses a pronounced energy density of 50.8 Wh kg−1 and remarkable cycling stability with a 4.3% deterioration of specific capacitance after 10 000 cycles. This work paves a new avenue to solve the two long‐standing significant challenges of MXene in the future.
Minimalist Tissue Engineering Approaches Using Low Material‐Based Bioengineered Systems
Authors: Correia Clara R. , Bjørge Isabel M. , Nadine Sara , Mano João F.
Published: March 2021

From an “over‐engineering” era in which biomaterials played a central role, now it is observed to the emergence of “developmental” tissue engineering (TE) strategies which rely on an integrative cell‐material perspective that paves the way for cell self‐organization. The current challenge is to engineer the microenvironment without hampering the spontaneous collective arrangement ability of cells, while simultaneously providing biochemical, geometrical, and biophysical cues that positively influence tissue healing. These efforts have resulted in the development of low‐material based TE strategies focused on minimizing the amount of biomaterial provided to the living key players of the regenerative process. Through a “minimalist‐engineering” approach, the main idea is to fine‐tune the spatial balance occupied by the inanimate region of the regenerative niche toward maximum actuation of the key living components during the healing process.
Rare‐Earth Incorporated Alloy Catalysts: Synthesis, Properties, and Applications
Authors: Zhang Shuai , Saji Sandra Elizabeth , Yin Zongyou , Zhang Hongbo , Du Yaping , Yan Chun‐Hua
Published: March 2021

To improve the performance of metallic catalysts, alloying provides an efficient methodology to design state‐of‐the‐art materials. As emerging functional materials, rare‐earth metal compounds can integrate the unique orbital structure and catalytic behavior of rare earth elements into metallic materials. Such rare‐earth containing alloy catalysts proffer an opportunity to tailor electronic properties, tune charged carrier transport, and synergize surface reactivity, which are expected to significantly improve the performance and stability of catalysis. Despite its significance, there are only few reviews on rare earth containing alloys or related topics. This review summarizes the composition, synthesis, and applications of rare earth containing alloys in the field of catalysis. Subsequent to comprehensively summarizing and constructively discussing the existing work, the challenges and possibilities of future research on rare‐earth metal compound materials are evaluated.
Smart Self‐Assembly Amphiphilic Cyclopeptide‐Dye for Near‐Infrared Window‐II Imaging
Authors: Chen Hao , Shou Kangquan , Chen Si , Qu Chunrong , Wang Zhiming , Jiang Lei , Zhu Mark , Ding Bingbing , Qian Kun , Ji Aiyan , Lou Hongyue , Tong Ling , Hsu Alexander , Wang Yuebing , Felsher Dean W. , Hu Zhenhua , Tian Jie , Cheng Zhen
Published: March 2021

Development of novel nanomaterials for disease theranostics represents an important direction in chemistry and precision medicine. Fluorescent molecular probes in the second near‐infrared window (NIR‐II, 1000–1700 nm) show high promise because of their exceptional high detection sensitivity, resolution, and deep imaging depth. Here, a sharp pH‐sensitive self‐assembling cyclopeptide‐dye, SIMM1000, as a smart nanoprobe for NIR‐II imaging of diseases in living animals, is reported. This small molecule assembled nanoprobe exhibits smart properties by responding to a sharp decrease of pH in the tumor microenvironment (pH 7.0 to 6.8), aggregating from small nanoprobe (80 nm at pH 7.0) into large nanoparticles (>500 nm at pH 6.8) with ≈20–30 times enhanced fluorescence compared with the non‐self‐assembled CH‐4T. It yields micrometer‐scale resolution in blood vessel imaging and high contrast and resolution in bone and tumor imaging in mice. Because of its self‐aggregation in acidic tumor microenvironments in situ, SIMM1000 exhibits high tumor accumulation and extremely long tumor retention (>19 days), while being excretable from normal tissues and safe. This smart self‐assembling small molecule strategy can shift the paradigm of designing new nanomaterials for molecular imaging and drug development.
Tip‐Induced Nano‐Engineering of Strain, Bandgap, and Exciton Funneling in 2D Semiconductors
Authors: Koo Yeonjeong , Kim Yongchul , Choi Soo Ho , Lee Hyeongwoo , Choi Jinseong , Lee Dong Yun , Kang Mingu , Lee Hyun Seok , Kim Ki Kang , Lee Geunsik , Park Kyoung‐Duck
Published: March 2021

The tunability of the bandgap, absorption and emission energies, photoluminescence (PL) quantum yield, exciton transport, and energy transfer in transition metal dichalcogenide (TMD) monolayers provides a new class of functions for a wide range of ultrathin photonic devices. Recent strain‐engineering approaches have enabled to tune some of these properties, yet dynamic control at the nanoscale with real‐time and ‐space characterizations remains a challenge. Here, a dynamic nano‐mechanical strain‐engineering of naturally‐formed wrinkles in a WSe2 monolayer, with real‐time investigation of nano‐spectroscopic properties is demonstrated using hyperspectral adaptive tip‐enhanced PL (a‐TEPL) spectroscopy. First, nanoscale wrinkles are characterized through hyperspectral a‐TEPL nano‐imaging with <15 nm spatial resolution, which reveals the modified nano‐excitonic properties by the induced tensile strain at the wrinkle apex, for example, an increase in the quantum yield due to the exciton funneling, decrease in PL energy up to ≈10 meV, and a symmetry change in the TEPL spectra caused by the reconfigured electronic bandstructure. Then the local strain is dynamically engineered by pressing and releasing the wrinkle apex through an atomic force tip control. This nano‐mechanical strain‐engineering allows to tune the exciton dynamics and emission properties at the nanoscale in a reversible fashion. In addition, a systematic switching and modulation platform of the wrinkle emission is demonstrated, which provides a new strategy for robust, tunable, and ultracompact nano‐optical sources in atomically thin semiconductors.
Self‐Healable and Eco‐Friendly Hydrogels for Flexible Supercapacitors
Authors: Babeli Ismael , Ruano Guillem , Puiggalí‐Jou Anna , Ginebra Maria‐Pau , Alemán Carlos , Garcia‐Torres Jose
Published: March 2021

One limitation of wearable electronics, and at the same time a challenge, is the lack of energy storage devices with multiple functionalities produced using clean and environmental‐friendly strategies. Here, a multifunctional conductive hydrogel containing poly(3,4‐ethylenedioxythiophene) (PEDOT) and alginate is fabricated, to be used as electrodes in supercapacitors, by applying water‐mediated self‐assembly and polymerization processes at room temperature. The interpenetration of both polymers allows the combination of flexibility and self‐healing properties within the same hydrogel together with the intrinsic biocompatibility and sustainability of such materials. Initially, PEDOT:polystyrene sulfonate and alginate aqueous solutions are mixed in two different proportions (1:1 and 1:3) and ionically crosslinked with CaCl2. Subsequently, re‐interpenetration of poly(hydroxymethyl‐3,4‐ethylenedioxythiophene) by anodic polymerization in CaCl2 aqueous solution is achieved. Re‐interpenetrated 1:3 PEDOT/alginate hydrogels show excellent capacitance values (35 mF cm−2) and good capacitance retention. In addition, the electrochemical properties are not significantly changed after many cutting/self‐healing cycles as observed by cyclic voltammetry. Therefore, this sustainably produced hydrogel shows promising properties for use in wearable energy storage devices.
Integration of High‐Performance Cost‐Effective Copper‐Metal‐Organic‐Nanocluster‐based Gate Dielectric for Next‐Generation CMOS Applications
Authors: Gupta Prachi , Kumar Rudra , Sharma Satinder K.
Published: March 2021

The suitability of metal‐organic frameworks (MOFs) as functional materials for future electronic logic devices with desirable dielectric constant, bandgap, high‐quality interface, low leakage current, and better compatibility is still an open challenge. Owing to the synergistic complementary properties of MOFs systems, a low‐cost copper‐metal‐organic nanoclusters (Cu‐MOCs) has been synthesized comprising inorganic copper metal unit allied organic m‐toluic acid ligand by facile sol–gel strategy. It offers large‐area thin‐films uniformity, high dielectric constant (κ ≈ 5.49), improved interfacial properties, dynamic switching behavior with the stimuli field, and extends the realization of metal‐organic‐framework dielectric for scalable complementary‐metal‐oxide‐semiconductor (CMOS) logic applications over customary hybrid counterparts. Various techniques such as single crystal X‐ray diffraction, X‐ray photoelectron spectroscopy, thermogravimetric analysis, and energy dispersive X‐ray spectroscopy have been used to validate the Cu‐MOCs formulation. In particular, the fabricated Cu‐MOCs, metal–insulator–semiconductor structures exhibit promising dynamic switching behavior responsive to the applied field, hysteresis‐free capacitance–voltage characteristics, low interfacial trap density (≈1.4 × 1011 eV−1 cm−2), low effective oxide charges (≈1.1 × 1011 cm−2), and noteworthy small leakage current density (≈1.29 nA cm−2 @ 1 V) ever since in electrical analysis. Cost‐effective novel Cu‐MOCs successfully demonstrate high‐performance, reliable gate dielectrics for next‐generation CMOS logic devices.
Patternable Semi‐Transparent Cathode using Thermal Evaporation for OLED Display Applications
Authors: Jung Sang Won , Kim Kwan‐Soo , Park Han‐un , Lampande Raju , Kim Seong Keun , Kim Jae‐Hyeon , Han Chang‐Wook , Choi Hyun‐Chul , Kwon Jang Hyuk
Published: March 2021

A new patternable semi‐transparent metal cathode, Zn:Mg (4:1 and 10:1) using the thermal evaporation process for organic light‐emitting diode (OLED) display applications is reported. A new Zn:Mg alloy film shows good surface morphology and almost no temperature effect on the shadow mask. The Zn:Mg layer with ratio of 4:1 and 10:1 shows sheet resistance of 33.2 and 39.2 Ω ϒ−1, respectively, at the thickness of 12 nm. The fabricated green top‐emitting OLED (TEOLED) with Zn:Mg cathode shows current efficiency of 79.3 cd A−1 and a color coordinates of (0.166, 0.755). These results show the possibility of high‐quality cathode patterning for various OLED display and sensor applications.