bluuebunny/crossref_metadata_2025 huggingface dataset:
Antinuclear autoantibodies in relation to bipolar affective disorder and lithium therapy
Authors: Spivak B , Radwan M , Bartur P , Mester R , Weizman A
Published: July 2002

We investigated the presence of antinuclear antibodies (ANA) in 63 drug free and lithium treated bipolar patients as compared to 37 healthy controls. Increased frequency of positive ANA was detected in bipolar patients in comparison to controls (19% vs 5%, respectively, P < 0.05). This finding was unrelated to lithium treatment. No antinative DNA antibodies or antihistone reactive antibodies were detected among the ANA positive subjects.
A new endogenous differentiating factor (myelopeptide‐4) for myeloid cells
Authors: Strelkov Leonid A , Mikhailova Augusta A , Fonina Larissa A , Petrov Rem V
Published: July 2002

Along with known lymphokines involved in the regulation of hematopoiesis, a new differentiating factor (myelopeptide‐4, MP‐4) for myeloid cells was found. The peptide (Phe‐Arg‐Pro‐Arg‐Ile‐Met‐Thr‐Pro) originally isolated from the culture medium of porcine bone marrow cell culture was examined for its ability to induce differentiation in two human myeloid leukemia cell lines, HL‐60 and K‐562. Agents with well‐known differentiation‐inducing activity, such as phorbol myristate acetate, dimethylsulfoxide and the lymphokines were used as a reference. It has been shown that MP‐4 significantly influences the integral characteristics of metabolism, expression of surface antigens and morphology of these cells. It decreased the level of chromosomal DNA synthesis and, in parallel, increased the total protein synthesis in both HL‐60 and K‐562 cells. MP‐4 induced the expression of CD14 monocyte‐specific surface antigen and the appearance of mature monocytes/macrophages in HL‐60 cell cultures. There was a good correlation of cell metabolic/morphological changes and the CD14 marker expression for HL‐60 cells. A similar phenomenon was observed in K‐562 cells treated with MP‐4 when the levels of hemoglobin synthesis were detected in their cytoplasm. Thus, we consider MP‐4 as a new endogenous differentiating factor for myeloid cells.
Bromodomain factor 1 (Bdf1) protein interacts with histones
Authors: Pamblanco Mercè , Poveda Ana , Sendra Ramon , Rodrı́guez-Navarro Susana , Pérez-Ortı́n José E. , Tordera Vicente
Published: July 2002

Using a yeast two‐hybrid assay we detected an interaction between the N‐terminal region of histone H4 (amino acids 1–59) and a fragment of the bromodomain factor 1 protein (Bdf1p) (amino acids 304–571) that includes one of the two bromodomains of this protein. No interaction was observed using fragments of histone H4 sequence smaller than the first 59 amino acids. Recombinant Bdf1p (rBdf1p) demonstrates binding affinity for histones H4 and H3 but not H2A and H2B in vitro. Moreover, rBdf1p is able to bind histones H3 and H4 having different degrees of acetylation. Finally, we have not detected histone acetyltransferase activity associated with Bdf1p.
A transient increase of snoN transcript by growth arrest upon serum deprivation and cell‐to‐cell contact
Authors: Mimura Naotoshi , Ichikawa Koji , Asano Akira , Nagase Takahiro , Ishii Shunsuke
Published: July 2002

To analyze the possible involvement of c‐ski and c‐sno during the course of in vitro myogenesis, expression of their transcripts during differentiation of a murine muscle cell line (C2C12) was monitored by competitive reverse transcription‐polymerase chain reaction (RT‐PCR). The transcripts of c‐snoN were temporarily increased 25‐fold above basal level at 12 h prior to the onset of transcription of muscle‐specific gene, e.g. myogenin and muscle creatine kinase, whereas c‐ski was expressed invariably. The transient increase of c‐snoN was blocked when myogenesis was interrupted by the presence of fetal calf serum in culture medium, probably due to growth factors being included; basic fibroblast growth factor (b‐FGF) blocked the transient increase whereas epidermal growth factor (EGF) did not, consistent with the inhibitory effect of b‐FGF and no effect of EGF on myotube formation of C2C12. In fibroblastic C3H10T1/2 cells, snoN exhibited a similar transient increase of transcript when growth arrested under the same conditions as for in vitro myogenesis, indicating that the expression of snoN is not sufficient to induce the onset of muscle differentiation and an unknown factor involved in myogenic cells is necessary. The transient increase of snoN transcript may represent a common entrance step of cells into the GO phase where muscle differentiation is substantiated, considering that it was observed upon growth arrest of fibroblastic C3H10T1/2 cells and prior to the elevation of MCK in C2C12 but undetected when entry into G0 was blocked by b‐FGF.
Liposome‐mediated DNA vaccination
Authors: Gregoriadis Gregory , Saffie Roghieh , de Souza J.Brian
Published: July 2002

Numerous reports have indicated that intramuscular injection of antigen‐coding naked plasmid DNA can trigger humoral and cell‐mediated protective immunity against infection. This follows DNA uptake by muscle fibres, leading to the expression and extracellular release of the antigen. Here it is shown for the first time that intramuscular immunization of mice with pRc/CMV HBS (encoding the S region of hepatitis B antigen; HBsAg) entrapped into positively charged (cationic) liposomes leads to greatly improved humoral and cell‐mediated immunity. These cationic liposome‐entrapped DNA vaccines generate titres of anti‐HBsAg IgG1 antibody isotype in excess of 100‐fold higher and increased levels of both IFN‐γ and IL‐4 when compared with naked DNA or DNA complexed with preformed similar (cationic) liposomes. It is likely that immunization with liposome‐entrapped plasmid DNA involves antigen‐presenting cells locally or in the regional draining lymph nodes.
The interaction of Ras with GTPase‐activating proteins
Authors: Wittinghofer Alfred , Scheffzek Klaus , Ahmadian Mohammad Reza
Published: July 2002

Ras plays a major role as a molecular switch in many signal transduction pathways which lead to cell growth and differentiation. The GTPase reaction of Ras is of central importance in the function of the switch since it terminates Ras‐effector interactions. GTPase‐activating proteins (GAPs) accelerate the very slow intrinsic hydrolysis reaction of the GTP‐bound Ras by several orders of magnitude and thereby act as presumably negative regulators of Ras action. The GTP hydrolysis of oncogenic mutants of Ras remains unaltered. In this review we discuss recent biochemical and structural findings relating to the mechanism of GAP action, which strengthen the hypothesis that GAP accelerates the actual cleavage step by stabilizing the transition state of the phosphoryl transfer reaction.
Detection and quantitation of cellularly derived amyloid β peptides by immunoprecipitation‐HPLC‐MS
Authors: Clarke Nigel J , Tomlinson Andy J , Ohyagi Yasumasa , Younkin Steven , Naylor Stephen
Published: July 2002

A quantitative method for detection of amyloid β peptides using immunoprecipitation‐HPLC‐mass spectrometry (IP‐LC‐MS) is described. Comparison of IP‐LC‐MS with sandwich ELISA revealed comparable results in the analysis of Aβ 1–40 and Aβ 1–42 derived from fetal guinea pig cell media and cell lysates. The use of IP‐LC‐MS not only allows a quantitative method for Aβ 1–40 and Aβ 1–42 peptides present in Alzheimer's disease (AD), but allows detection of other Aβ peptide species that may also play a role in the onset of AD in humans.
In vivo and in vitro evidence of basic fibroblast growth factor action in mouse mammary gland development
Authors: Lavandero Sergio , Chappuzeau Andrés , Sapag-Hagar Mario , Oka Takami
Published: July 2002

Basic fibroblast growth factor (bFGF) stimulated [3H]thymidine incorporation at all stages of development, although the magnitude of this effect was the greatest in cells derived from pregnant mice. Cells primed with insulin and bFGF synthesized more casein than cells not exposed to either hormone. bFGF inhibited casein synthesis and decreased the amounts of β‐casein and α‐lactalbumin transcripts in cells from pregnant animals simultaneously incubated with insulin, hydrocortisone and prolactin. bFGF content in mammary gland increased with puberty and pregnancy, but decreased markedly in lactation; the number of bFGF receptors in epithelial cells changed in parallel. These data suggest that bFGF may have a physiological role both in stimulating growth and in inhibiting functional differentiation of normal mouse mammary epithelial cells.
A novel mouse beta defensin, Defb2, which is upregulated in the airways by lipopolysaccharide
Authors: Morrison Gillian M , Davidson Donald J , Dorin Julia R
Published: July 2002

Studies have shown that beta defensins are present in the human airways and may be relevant to the pathogenesis of cystic fibrosis lung disease. Here we report the identification of a novel mouse gene, Defb2, which shows sequence similarity to previously described mouse and human airway beta defensins. Defb2 does not appear to be expressed in the airways of untreated mice but it is upregulated in response to lipopolysaccharide. The induced expression of this gene by an inflammatory stimulus strongly suggests that this defensin contributes to host defence at the mucosal surface of the airways.
Demonstration of cell‐specific phosphorylation of LTC4 synthase
Authors: Gupta Namrata , Nicholson Donald W. , Ford-Hutchinson Anthony W.
Published: July 2002

PMA‐induced leukotriene C4 synthase (LTC4S) phosphorylation was investigated over a period of 8 h in a monocytic cell line (THP‐1). The level of LTC4S phosphorylation was increased 3–5 fold over a 4 h period decreasing to basal levels after 8 h. This phosphorylation event was found to be specific to THP‐1 cells as there was a lack of LTC4S phosphorylation in both COS‐7 and K‐562 cells, and was also found to be dependent on the cellular confluency. In the presence of specific protein kinase C (PKC) inhibitors, a dose‐dependent inhibition of the phosphorylation of LTC4S became evident, an effect not seen with PKA and tyrosine kinase inhibitors. This represents the first direct demonstration of LTC4S phosphorylation in whole cells.
cDNA cloning, expression and characterization of human prostaglandin F synthase1
Authors: Suzuki-Yamamoto Toshiko , Nishizawa Mikio , Fukui Motonari , Okuda-Ashitaka Emiko , Nakajima Tatsuya , Ito Seiji , Watanabe Kikuko
Published: July 2002

A cDNA clone of prostaglandin F synthase (PGFS) was isolated from human lung by using cDNA of bovine lung‐type PGFS as a probe and its protein expressed in Escherichia coli was purified to apparent homogeneity. The human PGFS catalyzed the reduction of prostaglandin (PG) D2, PGH2 and phenanthrenequinone (PQ), and the oxidation of 9α,11β‐PGF2 to PGD2. The k
cat/K
m values for PGD2 and 9α,11β‐PGF2 were 21 000 and 1800 min−1 mM−1, respectively, indicating that the catalytic efficiency for PGD2 and 9α,11β‐PGF2 was the highest among the various substrates, except for PQ. The PGFS activity in the cytosol of human lung was completely absorbed with anti‐human PGFS antiserum. Moreover, mRNA of PGFS was expressed in peripheral blood lymphocytes and the expression in lymphocytes was markedly suppressed by the T cell mitogen concanavalin A. These results support the notion that human PGFS plays an important role in the pathogenesis of allergic diseases such as asthma.
Apoptosis in the placenta of pregnancies complicated with IUGR
Authors: Erel C.T , Dane B , Calay Z , Kaleli S , Aydinli K
Published: July 2002

Objective: In this study we have investigated the presence of apoptosis in the placental tissue of pregnancies complicated with intra‐uterine growth restriction (IUGR). Method: Placental samples were obtained from 22 normal third trimester pregnancies and 20 pregnancies complicated with IUGR. The criteria for fetal growth impairment were clinical evidence of sub‐optimal growth, ultrasonographic demonstration of deviation from normal percentiles of growth and birth weight under 10th percentile. Terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labelling (TUNEL) staining was used to demonstrate the apoptotic cells in all samples. Student‐t, Mann–Withney U‐test, Fisher exact test and Spearman correlation were used for statistical analysis. Result: We detected apoptosis in 10 placentas in the study group vs. none in the control group. Placentas from pregnancies complicated with IUGR demonstrated 0.12% (0.1%–0.4%) apoptotic cells. The rate of apoptotic cells in the placenta was significantly higher in pregnancies complicated with IUGR than normal uncomplicated pregnancy (P=0.0019). Apoptosis were more abundant in the trophoblasts, especially cytotrophoblasts, in the placenta. We could not find a correlation between the apoptosis in the placenta of pregnancies complicated with IUGR and birth weight, multi‐parity, gestational age, birth weight percentile and mode of delivery (C/S vs. vaginal delivery). Conclusion: We believe that the increased number of apoptosis in the placenta of pregnancies complicated with IUGR may have an important compensatory role to transmit nutrition and gas exchange easily to the fetus.
Breech labor on the WHO partograph
Authors: Lennox C.E , Kwast B.E , Farley T.M.M
Published: July 2002

Objectives: To assess the impact of breech labor management using the WHO partograph on fetal and maternal outcomes of labor. Method: All 1,740 breech presentations in a larger multicentre hospital‐based study in South East Asia of the use of the WHO partograph in labor management were studied. The partograph was introduced into each hospital during the study and a before and after analysis of various outcomes was conducted. Results: There were 923 breech presentations prior to implementation of the partograph and 817 after. The overall Cesarean section rate was 29.7% (21.6% emergency and 7.6% elective). Introducing the partograph reduced Cesarean sections for multigravida from 27.1% to 19.3% (non‐significant) but had no impact on the rate for primigravida (38.5% to 38.7%). Prolonged labor (>18 hours) was reduced significantly among multigravida and primigravida (P<0.05), despite a reduced use of oxytocin. Intrapartum stillbirths fell (non‐significantly) from 1.9% to 11.1% (all parties combined). Fetal outcome, as measured by intrapartum deaths and Apgar scores <7 at 1 minute, was significantly better (P<0.05) when delivery was by Cesarean section rather than vaginally, regardless of use of the partograph. Conclusion: The use of the WHO partograph in the management of breech labor reduces prolonged labor and (among multigravida) Cesarean sections and improves fetal outcome. In this study, however, Casarean section was a safer method of delivery for the baby, regardless of use of the partograph.
Persistent subchorionic hematoma with clinical symptoms until delivery
Authors: Seki H , Kuromaki K , Takeda S , Kinoshita K
Published: July 2002

Objective: This study was performed retrospectively to clarify the clinical features of persistent subchorionic hematoma with clinical symptoms until delivery. Methods: We studied all the 22 cases of persistent subchorionic hematoma with symptoms until delivery from 4763 singleton pregnant women delivered in our hospital from 1985 to 1996 inclusive to investigate their clinical course and pregnancy outcome. Results: The initial symptom of subchorionic hematoma was vaginal bleeding and/or uterine contractions. The onset of the symptoms showed two peaks at 9–11 and 30–31 weeks of gestation. The pregnancy outcome was spontaneous abortion in three cases (13.6%), premature labor in 17 cases (77.3%) or full‐term delivery in two cases (9.1%). Tocolysis was needed in 17 of the 22 cases (77.3%), of which 16 cases failed to prevent premature delivery. Conclusion: Persistent subchorionic hematoma with clinical symptoms until delivery is likely to result in abortion or premature labor, because that may be thought to be a severe type.
The influence of abortion legislation on maternal mortality
Authors: Singh K , Ratnam S.S
Published: July 2002

Worldwide some 20 million unsafe abortions take place each year and account for approximately 13% of all maternal mortality and serious complications associated with it, such as sepsis, hemorrhage and trauma. Only a quarter of all women in the world do not have any access to legal abortion, whereas 40% have a legal right to decide for themselves. This liberalization of abortion legislation has seen a tremendous drop in abortion‐related maternal mortality. Death from unsafe abortions are almost unknown in countries where abortion is available on request. Reduction of the need for induced abortion through the provision of good family planning services should be an integral part of healthcare. Consistent use of contraception greatly reduces the need for abortion, but it cannot completely eliminate this need. Thus, it is essential that safe medical abortion services should be made available to all women in the world in cases of contraceptive failure.
Construction of entropy solutions for one dimensional elastodynamics via time discretisation
Authors: Demoulini Sophia , Stuart David M.A , Tzavaras Athanasios E
Published: July 2002

It is shown that the variational approximation scheme for one-dimensional elastodynamics given by time discretisation converges, subsequentially, weakly and a.e. to a weak solution which satisfies the entropy inequalities. We also prove convergence under the restriction of positive spatial derivative (for longitudinal motions).

Pour les équations d’élasticité dynamiques à une variable d’espace on démontre que la méthode de discrétisation en la variable temps, résolue variationellement, produit une suite de solutions approchées convergeant, par une sous suite, faiblement et presque partout vers une solution faible classique qui satisfait les inégalités d’entropie. Nous prouvons aussi que le même résultat reste valable sous la restriction de positivité des dérivées partielles en la variable spatiale.
On the thermodynamic limit for Hartree–Fock type models
Authors: Lions P.-L , Catto I , Le Bris C
Published: July 2002

We continue here our study [10–13] of the thermodynamic limit for various models of Quantum Chemistry, this time focusing on the Hartree–Fock type models. For the reduced Hartree–Fock models, we prove the existence of the thermodynamic limit for the energy per unit volume. We also define a periodic problem associated to the Hartree–Fock model, and prove that it is well-posed.

Nous poursuivons dans cet article notre étude systématique [10–13] de la limite thermodynamique de divers modèles issus de la Chimie Quantique Moléculaire, en nous consacrant cette fois aux modèles de type Hartree–Fock. Pour le modèle de Hartree–Fock réduit, nous prouvons que l’énergie par unité de volume a une limite thermodynamique, que nous identifions. Nous définissons également un modèle périodique associé au modèle de Hartree–Fock, et nous démontrons qu’il est bien posé.
Hyaluronan suppressed nitric oxide production in the meniscus and synovium of rabbit osteoarthritis model
Authors: Takahashi Kenji , Hashimoto Sanshiro , Kubo Toshikazu , Hirasawa Yasusuke , Lotz Martin , Amiel David
Published: July 2002

Nitric oxide (NO) plays an important role in cartilage degeneration, and NO donors induce meniscus degeneration and synovium inflammation. This study evaluated the effect of intraarticular injections of hyaluronan (HA) on NO production in meniscus and synovium using an experimental osteoarthritis (OA) model. Thirty‐six New Zealand white rabbits underwent unilateral anterior cruciate ligament transection (ACLT), and were divided into three groups. Four weeks after ACLT, the HA group started to receive intraarticular HA injections once a week for 5 weeks; the vehicle group started to receive the carrier of HA; and the no injection group, no treatment. All ACLT knees were harvested at the 9th week. Meniscus and synovium sections were examined by immunohistochemistry for nitrotyrosine. The pieces of these two tissues were cultured for 24 h. Culture supernatants were analyzed for nitrite concentration. The amount of NO produced by the meniscus was much larger than that produced by the synovium. NO productions in the meniscus and synovium of the HA group were significantly lower than those of the other groups. The results suggest that the inhibition of NO production in meniscus and synovium might be a part of the mechanism of the therapeutic effect of HA on OA. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Maternal stress induces synaptic loss and developmental disabilities of offspring
Authors: Hayashi Aska , Nagaoka Masaaki , Yamada Kazuo , Ichitani Yukio , Miake Yoshiaki , Okado Nobuo
Published: July 2002

Mild prenatal stress affects the serotonergic system in the hippocampus of rat offspring. Pregnant rats were daily exposed to mild stress treatments (consisting of crowding and saline injection) during days 15 to 21 of pregnancy. Their offspring were assessed by a series of biochemical, histological and behavioral tests. On 35 days after birth, 5‐hydroxytryptamine (5‐HT) level was decreased by 17% (P< 0.05), whereas 5‐hydroxyindolacetic acid (5‐HIAA) level was increased by 18% (P< 0.05) in the offspring of prenatally stressed rats. The metabolic rate (5‐HIAA/5‐HT) was increased by 49% (P< 0.01). Synaptic density in the hippocampus of prenatally stressed offspring was also decreased by 32% (P< 0.0001) on postnatal day 35. There was no significant group difference in the spatial learning acquisition test of the Morris water maze ; however, in the reversal task, prenatally stressed 5‐week old rats spent more time than control animals searching for the platform of the pool. Escape latency in the cued test showed no significant difference. Together with data in our previous studies, that have shown 5‐HT to facilitate synapse formation and maintenance in the central nervous system, synaptic loss is suggested to occur in relation to changes of 5‐HT system in the hippocampus of prenatally stressed offspring. This may be associated with reported changes in behavior and learning ability in prenatally stressed offspring.
The neural mechanisms underlying cholinergic celldeath within the basal FOREBRAIN
Authors: Wenk Gary L. , Willard Lauren B.
Published: July 2002

The basal forebrain region includes a large group of cholinergic neurons within themedial septal area and nucleus basalis magnocellularis (NBM) that project to the hippocampusand throughout the neocortex, respectively. This chapter will consider the mechanisms thatinfluence why cholinergic cells within the NBM die and discuss studies that have manipulated thefeatures of these cells that could make them differentially vulnerable to degeneration with agingand Alzheimer's Disease (AD). This chapter will focus upon the NBM cholinergic system because thisregions typically demonstrates a greater degree of cell loss with aging and AD.
A double-blind placebo-controlled multicentre study of sertraline in the acute and continuation treatment of major depression
Authors: Olie JP , Gunn KP , Katz E
Published: July 2002

In a double-blind multicentre study of outpatients with DSM-III-R major depressive disorder, 129 sertraline and 129 placebo patients were evaluated over a 6-week period. Sertraline exhibited a significantly greater (P < 0.001) antidepressant effect compared to placebo as measured by the HAM-D, MADRS, CGI-S and CGI-I. In the subset of patients with severe depression (baseline HAM-D ≥ 25), sertraline was also significantly more effective than placebo (P < 0.05). Side effects were more commonly reported in sertraline (59%) compared to placebo (38%) patients; the most common being nausea, headache and insomnia. A subset of 107 patients (66 sertraline; 41 placebo) who were defined as responders (CGI-I of 1 or 2) after 6 weeks treatment were entered into a 20-week continuation phase. In this responder subset, there was continuing improvement in both groups of patients, but with no significant differences in mean HAM-D or MADRS between the groups. However, a higher number of sertraline patients were associated with a persistent pattern of improvement relative to placebo (P < 0.05). The incidence of side effects was similar in sertraline (52%) and placebo (49%) treated patients in the continuation period.
Quality of life instruments in depression
Authors: Bech P
Published: July 2002

Major depression is one of the medical disorders in which quality of life instruments have most often been applied. It is important to distinguish between disease-dependent scales (ie, scales measuring the symptoms of major depression, such as the Beck Depression Inventory) and generic scales (ie, scales measuring self-reported states without reference to a specific disorder, such as the WHO well-being scale). The empirical use of generic scales for quality of life major depression has indicated that they can predict relapse and compliance. In the future, more trials comparing the different treatments with cost-effectiveness vs quality of life in major depression are required.
Progressive cardiac dysfunction in adriamycin‐induced cardiomyopathy rats
Authors: Teraoka Kunihiko , Hirano Masaharu , Yamaguchi Kyoko , Yamashina Akira
Published: July 2002

Cardiotoxicity is a limiting factor in the treatment of cancer with adriamycin. We administered adriamycin by a method which minimizes the risk of peritonitis in an adriamycin‐induced cardiomyopathy rat model. Sixty male Wistar rats were given 1 mg/kg of adriamycin intraperitoneally 15 times over a 3‐week period (total dose, 15 mg/kg) to induce the cardiomyopathy model. Fifteen control rats received 10 ml/kg body wt. saline 15 times over 3 weeks. The animals were observed for 12 weeks and assessed for mortality, and cardiac volume and function was analyzed by echocardiography at 4, 8, and 12 weeks. In rats treated with adriamycin, the cumulative mortality was 35.8% while in the controls, none of the rats died. Left ventricular diameter of the systole (LVDs) was significantly increased at 4 weeks (4.5 vs. 3.3 mm; P<0.001). Left ventricular diameter of the diastole (LVDd) was significantly increased at 12 weeks (7.9 vs. 7.0 mm; P<0.01) and the fractional shortening (FS) was significantly decreased at 8 weeks (33.4% vs. 50.0%; P<0.01) in the adriamycin‐treated rats. This administration method appears to be useful for investigating the cardiac effect of adriamycin while avoiding the influence of peritonitis typically caused by an intraperitoneal injection of higher single doses of adriamycin.
That's my spot! Examining spatial habit formation in a naturalistic setting
Authors: Zhu Mona J. H. , Risko Evan F.
Published: April 2021

Although we are constantly making spatial decisions about where to place our objects and ourselves, few studies in psychology have investigated this phenomenon in‐depth. In the current study, we examined how spatial decisions are made over time by tracking students' seating choices in classrooms over the course of a semester (i.e., 12 weeks). We found that seating choice became more fixed over time (i.e., a decrease in the distance between seats chosen on adjacent days), though this was disrupted by individuals' time of arrival to class; latecomers often sat further away from where they last sat. We also observed a surprising de‐stabilization of this pattern on the last day of class wherein seating choices became more varied. These results suggest that although spatial preference stabilizes over time, this pattern of stabilization may weaken once individuals no longer expect to occupy that space in the future.
Asymmetric Allylation Catalyzed by Chiral Phosphoric Acids: Stereoselective Synthesis of Tertiary Alcohols and a Reagent‐Based Switch in Stereopreference
Authors: Lazzarotto Mattia , Hartmann Peter , Pletz Jakob , Belaj Ferdinand , Kroutil Wolfgang , Payer Stefan E. , Fuchs Michael
Published: April 2021

The substrate scope of the asymmetric allylation with zinc organyls catalyzed by 3,3‐bis(2,4,6‐triisopropylphenyl)‐1,1‐binaphthyl‐2,2‐diyl hydrogenphosphate (TRIP) has been extended to non‐cyclic ester organozinc reagents and ketones. Tertiary chiral alcohols are obtained with ee's up to 94% and two stereogenic centers can be created. Compared to the previous lactone reagent the stereopreference switches almost completely, proving the fact that the nature of the organometallic compound is of immense importance for the asymmetry of the product.

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Recent Advances in Metal‐Catalyzed Functionalization of Indoles
Authors: Urbina Kelvin , Tresp David , Sipps Karli , Szostak Michal
Published: April 2021

Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances in the selective functionalization of indoles have been reported. Although the most important advances have been powered by transition metal catalysis, exceedingly useful methods in the absence of transition metals have also been reported. In this review, we provide an overview of functionalization reactions of indoles that have been published in the last years with a focus on the most recent advances, aims, and future trends. The review is organized by the positional selectivity and type of methods used for functionalization. In particular, we discuss major advances in transition‐metal‐catalyzed C−H functionalization at the classical C2/C3 positions, transition‐metal‐catalyzed C−H functionalization at the remote C4/C7 positions, transition‐metal‐catalyzed cross‐coupling, and transition‐metal‐free functionalization.

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Swelling‐Induced Symmetry Breaking: A Versatile Approach to the Scalable Production of Colloidal Particles with a Janus Structure
Authors: Qiu Jichuan , Chen Zitao , Chi Miaofang , Xia Younan
Published: April 2021

Janus particles are widely sought for applications related to colloidal assembly, stabilization of emulsions, and development of active colloids, among others. Here we report a versatile route to the fabrication of well‐controlled Janus particles by simply breaking the symmetry of spherical particles with swelling. When a polystyrene (PS) sphere covered by a rigid shell made of silica or polydopamine is exposed to a good solvent for PS, a gradually increased pressure will be created inside the shell. If the pressure becomes high enough to poke a hole in the shell, the spherical symmetry will break while pushing out the swollen PS through the opening to generate a Janus particle comprised of two distinct components. One of the components is made of PS and its size is controlled by the extent of swelling. The other component is comprised of the rigid shell and remaining PS, with its overall diameter determined by the original PS sphere and the rigid shell. This solution‐based route holds promises for the scalable production of complex Janus particles with a variety of compositions and in large quantities.
Bridging Thermal Catalysis and Electrocatalysis: Catalyzing CO2 Conversion with Carbon‐Based Materials
Authors: Koshy David M. , Nathan Sindhu S. , Asundi Arun S. , Abdellah Ahmed M. , Dull Samuel M. , Cullen David A. , Higgins Drew , Bao Zhenan , Bent Stacey F. , Jaramillo Thomas F.
Published: April 2021

Understanding the differences between reactions driven by elevated temperature or electric potential remains challenging, largely due to materials incompatibilities between thermal catalytic and electrocatalytic environments. We show that Ni, N‐doped carbon (NiPACN), an electrocatalyst for the reduction of CO2 to CO (CO2R), can also selectively catalyze thermal CO2 to CO via the reverse water gas shift (RWGS) representing a direct analogy between catalytic phenomena across the two reaction environments. Advanced characterization techniques reveal that NiPACN likely facilitates RWGS on dispersed Ni sites in agreement with CO2R active site studies. Finally, we construct a generalized reaction driving‐force that includes temperature and potential and suggest that NiPACN could facilitate faster kinetics in CO2R relative to RWGS due to lower intrinsic barriers. This report motivates further studies that quantitatively link catalytic phenomena across disparate reaction environments.
Palladium‐Catalyzed Cascade to Benzoxepins by Using Vinyl‐Substituted Donor–Acceptor Cyclopropanes
Authors: Faltracco Matteo , van de Vrande Koen N. A. , Dijkstra Martijn , Saya Jordy M. , Hamlin Trevor A. , Ruijter Eelco
Published: April 2021

A palladium‐catalyzed intermolecular cascade (4+3) cyclocondensation of salicylaldehydes and vinylcyclopropanes is reported. A key feature of the reaction is the use of a phosphonate group as an acceptor moiety on the cyclopropane, exploiting its propensity to undergo olefination with aldehydes. Subsequent O‐allylation enabled the formation of a range of substituted benzoxepinsWith a novel chiral ligand, the products were obtained in generally good yield and with reasonable enantioselectivity.
Fe(III)‐catalyzed Oxidative Povarov Reaction with Molecular Oxygen Oxidant
Authors: Park Du Yong , Hwang Joon Young , Kang Eun Joo
Published: April 2021

The synthesis of tetrahydroquinoline derivatives from dimethyl anilines and enamides has been developed by Fe(III)‐phenanthroline complex under aerobic condition. The oxidation of tertiary anilines involving a single electron transfer of Fe(phen)3(PF6)3 afforded the iminium ion intermediate, which reacted with electron‐rich alkenes to build a six‐membered N‐heterocycles containing quaternary carbon center via the oxidative Povarov reaction process.
Tuning a pyrazoline‐based fluorogenic reagent, 3‐naphthyl‐1‐(4‐trifluoromethyl)‐5‐(4‐carboxy phenyl)‐2‐pyrazoline for sensitive precolumn derivatization of aliphatic alcohols and trace analysis by RP‐HPLC with fluorescence detection
Authors: Al‐Sabahi Amal , Al‐Busafi Saleh , Varghese Beena , Al‐Kindy Salma , Suliman Fakhreldin
Published: April 2021

A new member of the pyrazoline family, 3‐naphthyl‐1‐(4‐trifluoromethyl)‐5‐(4‐carboxy phenyl)‐2‐pyrazoline has been evaluated as a precolumn derivatization reagent for the analysis of primary alcohols using HPLC. The simultaneous separation of eight alcohol derivatives (C1–C8) within 15 min was achieved on a reverse‐phase C8 column with an isocratic elution mode. The derivatives were detected with fluorescence at an emission wavelength of 470 nm when excited at 360 nm. The identification of the corresponding derivatives was carried out by LC–MS/MS and all showed their characteristic parent peak in negative ion mode. The proposed method was validated using normal analytical tools and was found to be excellent. As a preliminary application, our method was used to determine ethanol concentration in alcohol‐containing chocolates and cough syrup.
Sustainable development in the craft brewing industry: A case study of Iowa brewers
Authors: Rosburg Alicia , Grebitus Carola
Published: April 2021

The rapid expansion of the resource‐intensive brewing industry has led to U.S. and state‐level initiatives to encourage sustainable craft brewing practices. These efforts raise questions about brewers' current brewing practices and the conditions and factors that might influence a brewer's decision to adopt sustainable practices. We conducted an in‐depth survey of Iowa craft brewers in 2019 to evaluate current sustainability practices within breweries. In addition, we elicited brewer perceptions regarding consumer preferences and willingness‐to‐pay for sustainably produced beer. We analyze these factors together with data on brewery production characteristics and the brewer's personal beliefs and demographics. While most breweries in our sample track key environmental metrics to some degree, many of them lack environmental plans. Further, we find significant variation in the degree to which brewers believe there is opportunity to leverage sustainable brewing practices to charge consumers a higher price. We also provide insight on relationships between environmental practices and potential resources provided to breweries. These findings improve our understanding of craft brewers' tradeoffs regarding sustainable brewing practices that could apply more generally to other resource‐intensive sectors.
The challenges of migrating an active learning classroom online in a crisis
Authors: Luburić Nikola , Slivka Jelena , Sladić Goran , Milosavljević Gordana
Published: April 2021

The coronavirus disease of 2019 (COVID‐19) pandemic has severely crippled our globalized society. Despite the chaos, much of our civilization continued to function, thanks to contemporary information and communication technologies. In education, this situation required instructors and students to abandon the traditional face‐to‐face lectures and move to a fully online learning environment. Such a transition is challenging, both for the teacher tasked with creating digital educational content, and the student who needs to study in a new and isolated working environment. As educators, we have experienced these challenges when migrating our university courses to an online environment. Through this paper, we look to assist educators with building and running an online course. Before we needed to transition online, we researched and followed the best practices to establish various digital educational elements in our online classroom. We present these elements, along with guidance regarding their development and use. Next, we designed an empirical study consisting of two surveys, focus group discussions, and observations to understand the factors that influenced students' engagement with our online classroom. We used the same study to evaluate students' perceptions regarding our digital educational elements. We report the findings and define a set of recommendations from these results to help educators motivate their students and develop engaging digital educational content. Although our research is motivated by the pandemic, our findings and contributions are useful to all educators looking to establish some form of online learning. This includes developers of massive open online courses and teachers promoting blended learning in their classrooms.
From systematic literature review to a conceptual framework for consumer disposal behavior towards personal communication devices
Authors: Phulwani Payal R. , Kumar Divesh , Goyal Praveen
Published: April 2021

Personal communication devices have made their way into each and every household. The complex nature of e‐waste, and its generation at an amplified pace calls for serious attention of policy makers, managers, educators and researchers. The paper presents a structured literature review of peer‐reviewed journal publications in the research area of disposal behavior of consumers with respect to their personal electronics. Also, it discusses the concepts and theoretical underpinnings to understand consumer disposal behavior based on extensive literature review. These theoretical foundations further help in framing the hypothesis and proposing the conceptual model. The proposed model is based on Theory of Planned Behavior. It studies the relationship between the core constructs: attitude, subjective norms and perceived behavioral control, and includes awareness of consequences derived from the Value‐Belief‐Norm Theory. The model will also prove useful in understanding the impact of environmentally responsible disposal intention of personal electronics and its relationship with actual behavior. The role of external influences in the form of moderators is also taken into consideration while developing the model. It is expected that the research will help provide useful insights to literature on environmentally responsible disposal.
Angiotensin II, ATP and high extracellular potassium induced intracellular calcium responses in primary rat brain endothelial cell cultures
Authors: García‐Carlos Carlos Antonio , Camargo‐Loaiza Julio Andrés , García‐Villa Denisse , López‐Cervantes José Guillermo , Domínguez‐Avila J. Abraham , González‐Aguilar Gustavo A. , Astiazaran‐Garcia Humberto , Montiel‐Herrera Marcelino
Published: April 2021

The meninges shield the nervous system from diverse, rather harmful stimuli and pathogens from the periphery. This tissue is composed of brain endothelial cells (BECs) that express diverse ion channels and chemical‐transmitter receptors also expressed by neurons and glial cells to communicate with each other. However, information about the effects of ATP and angiotensin II on BECs is scarce, despite their essential roles in blood physiology. This work investigated in vitro if BECs from the meninges from rat forebrain respond to ATP, angiotensin II and high extracellular potassium, with intracellular calcium mobilizations and its second messenger‐associated pathways. We found that in primary BEC cultures, both ATP and angiotensin II produced intracellular calcium responses linked to the activation of inositol trisphosphate receptors and ryanodine receptors, which led to calcium release from intracellular stores. We also used RT‐PCR to explore what potassium channel subunits are expressed by primary BEC cultures and freshly isolated meningeal tissue, and which might be linked to the observed effects. We found that BECs mainly expressed the inward rectifier potassium channel subunits Kir1.1, Kir3.3, Kir 4.1 and Kir6.2. This study contributes to the understanding of the functions elicited by ATP and angiotensin II in BECs from rat meninges.

SIGNIFICANCE OF THE STUDY

Brain endothelial cells (BECs) express diverse ion channels and membrane receptors, which they might use to communicate with neurons and glia. This work investigated in vitro, if BECs from the rat forebrain respond to angiotensin II and ATP with intracellular calcium mobilizations. We found that these cells did respond to said substances with intracellular calcium mobilizations linked to inositol trisphosphate and ryanodine receptor activation, which led to calcium release from intracellular stores. These findings are important because they might uncover routes of active communication between brain cells and endothelial cells.
Direct Observation of the Self‐Aggregation of R3R4 Bi‐repeat of Tau Protein
Authors: Jayan Parvathy , Vahid Arshad A. , Kizhakkeduth Safwa T. , Muhammed Shafeek O. H. , Shibina Ajmala B. , Vijayan Vinesh
Published: April 2021

Abstract: Different cryo‐EM derived atomic models of in vivo tau filaments from patients with tauopathies consisted of R3 and R4 repeats of the microtubule‐binding domain. In comparison, only the R3 repeat forms the core of the heparin‐induced fibrils of the three repeat tau isoforms. For developing therapeutics, it is desirable to have an in vitro tau aggregation system producing fibrils corresponding to the disease morphology. Here we report the self‐aggregation of truncated tau segment R3R4 peptide without requiring heparin for aggregation induction. We used NMR spectroscopy and other biophysical methods to monitor the self‐aggregation of R3R4. We identified the hexapeptide region in R3 and β‐turn region in R4 as the aggregation initiating region of the protein. The solid‐state NMR of self‐aggregated R3R4 fibrils demonstrated that in addition to R3 residues, residues of R4 were also part of the fibril filaments. The presence of both R3 and R4 residues in the aggregation process and the core of fibril filaments suggest that the aggregation of R3R4 might resemble the in vivo aggregation process.
Quadruply BN‐Fused Tetrathia[8]circulenes with Flexible Frameworks: Synthesis, Structures and Properties
Authors: Akahori Shuhei , Sasamori Takahiro , Shinokubo Hiroshi , Miyake Yoshihiro
Published: April 2021

Quadruply BN‐fused tetrathia[8]circulenes were synthesized through four‐fold electrophilic borylation. The single‐crystal X‐ray diffraction analysis revealed that the BN‐fused tetrathia[8]circulene with peripheral phenyl groups exhibits crystal polymorphism, in which the circulene core adopts both planar and saddle conformations in the solid state. The experimental and theoretical studies revealed that the weaker aromaticity of azaborine compared with benzene renders the flexibility of the BN‐fused tetrathia[8]circulenes.
Activation of a Copper Biscarbene Mechano‐Catalyst Using Single‐Molecule Force Spectroscopy Supported by Quantum Chemical Calculations
Authors: Sammon Matthew S. , Biewend Michel , Michael Philipp , Schirra Simone , Ončák Milan , Binder Wolfgang H. , Beyer Martin K.
Published: April 2021

Single‐molecule force spectroscopy allows investigation of the effect of mechanical force on individual bonds. By determining the forces necessary to sufficiently activate bonds to trigger dissociation, it is possible to predict the behavior of mechanophores. The force necessary to activate a copper biscarbene mechano‐catalyst intended for self‐healing materials was measured. By using a safety line bypassing the mechanophore, it was possible to pinpoint the dissociation of the investigated bond and determine rupture forces to range from 1.6 to 2.6 nN at room temperature in dimethyl sulfoxide. The average length‐increase upon rupture of the Cu−C bond, due to the stretching of the safety line, agrees with quantum chemical calculations, but the values exhibit an unusual scattering. This scattering was assigned to the conformational flexibility of the mechanophore, which includes formation of a threaded structure and recoiling of the safety line.
A Cytotoxic Bis(1,2,3‐triazol‐5‐ylidene)carbazolide Gold(III) Complex Targets DNA by Partial Intercalation
Authors: van der Westhuizen Danielle , Slabber Cathryn A. , Fernandes Manuel A. , Joubert Daniël F. , Kleinhans George , van der Westhuizen C. Johan , Stander André , Munro Orde Q. , Bezuidenhout Daniela I.
Published: April 2021

The syntheses of bis(triazolium)carbazole precursors and their corresponding coinage metal (Au, Ag) complexes are reported. For alkylated triazolium salts, di‐ or tetranuclear complexes with bridging ligands were isolated, while the bis(aryl) analogue afforded a bis(carbene) AuI‐CNC pincer complex suitable for oxidation to the redox‐stable [AuIII(CNC)Cl]+ cation. Although the ligand salt and the [AuIII(CNC)Cl]+ complex were both notably cytotoxic toward the breast cancer cell line MDA‐MB‐231, the AuIII complex was somewhat more selective. Electrophoresis, viscometry, UV‐vis, CD and LD spectroscopy suggest the cytotoxic [AuIII(CNC)Cl]+ complex behaves as a partial DNA intercalator. In silico screening indicated that the [AuIII(CNC)Cl]+ complex can target DNA three‐way junctions with good specificity, several other regular B‐DNA forms, and Z‐DNA. Multiple hydrophobic π‐type interactions involving T and A bases appear to be important for B‐form DNA binding, while phosphate O⋅⋅⋅Au interactions evidently underpin Z‐DNA binding. The CNC ligand effectively stabilizes the AuIII ion, preventing reduction in the presence of glutathione. Both the redox stability and DNA affinity of the hit compound might be key factors underpinning its cytotoxicity in vitro.