bluuebunny/crossref_metadata_2025 huggingface dataset:
Lactoferrin inhibits the binding of lipopolysaccharides to L‐selectin and subsequent production of reactive oxygen species by neutrophils
Authors: Baveye Sophie , Elass Elisabeth , Mazurier Joël , Legrand Dominique
Published: July 2002

The activation of leukocytes by lipopolysaccharides (LPS), resulting in the oxidative burst, contributes to the pathogenesis of septic shock. The binding of LPS to L‐selectin, which was reported as a serum‐independent LPS receptor on neutrophils, induces the production of oxygen free radicals. Human lactoferrin (hLf), an anti‐inflammatory glycoprotein released from neutrophil granules during infection, binds to LPS. In this study, we investigated the capacity of hLf to inhibit the L‐selectin‐mediated activation of neutrophils. Our experiments revealed that hLf prevents the binding of LPS to L‐selectin in a concentration‐dependent manner. Inhibition was maximum (87.7±0.5%) at a concentration of 50 μg/ml of hLf. Furthermore, hLf inhibited up to 55.4±0.5% of the intracellular hydrogen peroxide production induced by LPS in neutrophils. These findings suggest that the anti‐inflammatory properties of hLf are due, at least in part, to their ability to prevent the binding of LPS to neutrophil L‐selectin.
Novel Dictyostelium unconventional myosin, MyoM, has a putative RhoGEF domain
Authors: Oishi Noboru , Adachi Hiroyuki , Sutoh Kazuo
Published: July 2002

We have cloned a novel unconventional myosin gene myoM in Dictyostelium. Phylogenetic analysis of the motor domain indicated that MyoM does not belong to any known subclass of the myosin superfamily. Following the motor domain, two calmodulin‐binding IQ motifs, a putative coiled‐coil region, and a Pro, Ser and Thr‐rich domain, lies a combination of dbl homology and pleckstrin homology domains. These are conserved in Rho GDP/GTP exchange factors (RhoGEFs). We have identified for the first time the RhoGEF domain in the myosin sequences. The growth and terminal developmental phenotype of Dictyostelium cells were not affected by the myoM
− mutation. Green fluorescent protein‐tagged MyoM, however, accumulated at crown‐shaped projections and membranes of phase lucent vesicles in growing cells, suggesting its possible roles in macropinocytosis.
Decreased expression of the gut‐enriched Krüppel‐like factor gene in intestinal adenomas of multiple intestinal neoplasia mice and in colonic adenomas of familial adenomatous polyposis patients
Authors: Dang Duyen T. , Bachman Kurtis E. , Mahatan Channing S. , Dang Long H. , Giardiello Francis M. , Yang Vincent W.
Published: July 2002

Gut‐enriched Krüppel‐like factor (GKLF) is a zinc finger‐containing transcription factor, the expression of which is associated with growth arrest. We compared Gklf expression in intestinal and colonic adenomas to normal mucosa in multiple intestinal neoplasia (Min) mice and familial adenomatous polyposis (FAP) patients, respectively, using semi‐quantitative RT‐PCR. In Min mice, the level of Gklf transcript is highest in normal‐appearing intestinal tissues and decreases as the size of the adenoma increases. In FAP patients, the level of GKLF transcript is lower in adenomas compared to paired normal‐appearing mucosa from the same patient or normal colonic mucosa from control individuals without FAP. The possibility of DNA methylation as a cause for the decreased expression of Gklf in adenomas of Min mice was investigated by methylation‐specific PCR. Results indicate that the Gklf gene is not methylated in either normal or tumorous tissues. The findings of our study are therefore consistent with the potential role of GKLF as a negative growth regulator of gut epithelial cells.
Selective stimulation of somatostatin receptor subtypes: differential effects on Ras/MAP kinase pathway and cell proliferation in human neuroblastoma cells
Authors: Cattaneo Maria Grazia , Taylor John E. , Culler Michael D. , Nisoli E. , Vicentini Lucia M.
Published: July 2002

In previous studies we have showed that somatostatin (SST) inhibits cell division, mitogen‐activated protein (MAP) kinase and Ras activity in the human neuroblastoma cell line SY5Y. In the present study, we have assessed the role of a series of SST analogs, three of which were selective for SSTR1, SSTR2 or SSTR5, in these cellular events. All the analogs inhibited forskolin‐induced cAMP accumulation. Selective stimulation of SSTR1 or SSTR2 but not of SSTR5 inhibited platelet‐derived growth factor (PDGF)‐induced [3H]thymidine incorporation. The three analogs inhibited PDGF‐stimulated MAP kinase activity, at least at an early time. In contrast, none of the analogs used individually was able to inhibit PDGF‐stimulated Ras activity. A combined stimulation of SSTR2 and SSTR5 was necessary to obtain a significant inhibitory effect, suggesting the possibility of receptor heterodimerization. These results indicate that SST inhibition of Ras and MAP kinase activities takes place via different pathways and that SST inhibition of PDGF‐induced cell proliferation occurs via a Ras‐independent pathway.
ATP‐driven rotation of the γ subunit in F1‐ATPase
Authors: Weber Joachim , Nadanaciva Sashi , Senior Alan E
Published: July 2002

We present a mechanism for F1‐ATPase in which hydrolysis of MgATP in the high‐affinity catalytic site at the α/β interface drives rotation of the γ subunit via conformational changes in the α subunit. During hydrolysis, transition state formation and separation of Pi from MgADP causes movement of portions of α, transmitted via two Arg residues which are hydrogen‐bonded to the γ‐phosphate of MgATP, αArg376 and βArg182; the latter is also hydrogen‐bonded to interfacial α residues between α346 and α349. Changes in α conformation then push on γ, resulting in rotation. Supporting evidence from the literature and from new data is discussed.
Regulation of cardiomyocyte apoptosis by redox‐sensitive transcription factors
Authors: Maulik N. , Sasaki H. , Addya S. , Das D.K.
Published: July 2002

Reperfusion of ischemic myocardium results in apoptotic cell death and DNA fragmentation. Several transcription factors are known to regulate the apoptotic cell death. This study sought to examine the regulation of cardiomyocyte apoptosis by these transcription factors. Isolated working rat hearts were divided into six groups: control, 15 min ischemia, 60 min ischemia, 15 min ischemia followed by 2 h reperfusion, ischemic stress adaptation by subjecting the hearts to four cyclic episodes to 5 min ischemia, each followed by 10 min of reperfusion, and adaptation followed by 15 min ischemia and 2 h reperfusion. Redox‐regulated transcription factors, NFκB and AP‐1 and the expression of two anti‐ and pro‐apoptotic genes, Bcl‐2 and p53 were determined. The results demonstrated NFκB and AP‐1 progressively and steadily increased as a function of the duration of ischemia. In the adapted heart, NFκB binding remained high while AP‐1 binding was lowered to almost baseline value. The anti‐oxidant gene, Bcl‐2 was downregulated in the ischemic/reperfused heart, but upregulated in the preconditioned myocardium. Significant induction of the expression of p53 occurred after ischemia and reperfusion. Apoptotic cells were barely detected in the adapted myocardium which was subjected to the same ischemia/reperfusion protocol. The results demonstrate for the first time differential regulation of cardiomyocyte apoptosis by pro‐ and anti‐apoptotic transcription factors and genes as a function of different durations of ischemia and reperfusion.
cis‐Inhibition of proteasomal degradation by viral repeats: impact of length and amino acid composition
Authors: Sharipo Anatoly , Imreh Martha , Leonchiks Ainars , Brändén Carl-Ivar , Masucci Maria G.
Published: July 2002

The Gly–Ala repeat (GAr) of the Epstein–Barr virus nuclear antigen 1 is a cis acting inhibitor of ubiquitin–proteasome proteolysis. We have investigated the capacity of various repeats to inhibit the turnover of the proteasomal substrate IκBα. Inhibition of TNFα‐induced degradation was achieved by insertion of octamers containing three alanines or valines, interspersed by no more then three consecutive glycines. The inhibitory activity was abolished by increasing the length of the spacer, by eliminating the spacers, or by substitution of a single hydrophobic residue with a polar or charged residue. A serine containing octamer was inactive but inhibition was partially restored by insertion of three consecutive repeats. These findings suggest a model where inhibition requires the interaction of at least three alanine residues of the GAr in a β‐strand conformation with adjacent hydrophobic binding pockets of a putative receptor.
AtBS14a and AtBS14b, twoBet1/Sft1‐like SNAREs fromArabidopsis thalianathat complement mutations in the yeastSFT1gene1
Authors: Tai William C.S. , Banfield David K.
Published: July 2002

SNAREs are membrane‐associated proteins that play a central role in vesicle targeting and intra‐cellular membrane fusion reactions in eukaryotic cells. Here we describe the identification of AtBS14a and AtBS14b, putative SNAREs fromArabidopsis thalianathat share 60% amino acid sequence identity. Both AtBS14a and BS14b are dosage suppressors of the temperature‐sensitive growth defect insft1‐1cells and over‐expression of either AtBS14a or AtBS14b can support the growth ofsft1Δ cells but notbet1Δ cells. These data together with structure–function and biochemical studies presented herein suggest that AtBS14a and AtBS14b share properties that are consistent with them being members of the Bet1/Sft1 SNARE protein family.
Dynamic chromatin remodeling on the HER2 promoter in human breast cancer cells
Authors: Mishra Sandip K , Mandal Mahitosh , Mazumdar Abhijit , Kumar Rakesh
Published: July 2002

Deregulation of the HER2 oncogene occurs in 30% of human breast cancers and correlates with poor prognosis and increased propensity for metastasis. Since the molecular basis of HER2 overexpression in human cancers is not known, we sought to determine whether chromatin remodeling pathways are involved in the regulation of HER2 expression. We report that compared with breast cancer cells expressing a low level of HER2, HER2‐overexpressing breast cancer cells contained significantly higher levels of acetylated and phosphorylated histone H3, and acetylated histone H4 associated with the HER2 promoter. Decreased recruitment of histone deacetylases in the promoter is also noted in the HER2‐overexpressing cell. The association of acetylated histone H4 with HER2 gene chromatin and HER2 expression in breast cancer cells was upregulated by an inhibitor of histone deacetylases. Treatment with histone deacetylase inhibitor also reduced the association of histone deacetylase‐1 and ‐2 with the HER2 promoter. In addition, the tumor promoters 12‐O‐tetradecanoylphorbol‐13‐acetate and okadaic acid stimulated the association of phosphorylated histone H3 on serine 10 with the HER2 promoter and also stimulated HER2 expression. These findings identify histone acetylation and histone phosphorylation as novel regulatory modifications that target HER2 gene chromatin, and suggest that elevated levels of these chromatin‐relaxing components in the vicinity of the HER2 gene promoter may constitute an important non‐genomic mechanism of HER2 overexpression in human breast cancer.
Tight‐binding inhibitory sequences against pp60c−src identified using a random 15‐amino‐acid peptide library
Authors: Nishi Toru , Budde Raymond J.A. , McMurray John S. , Obeyesekere Nihal U. , Safdar Naueen , Levin Victor A. , Saya Hideyuki
Published: July 2002

A bacteriophage peptide library containing a random 15‐amino‐acid insert was screened for identification of peptide sequence(s) that bind pp60
c−src
. Sequencing the random insert from more than 100 virions indicated that more than 60% of the phage virions that bound to this enzyme contained a GXXG sequence motif in which X was frequently a hydrophobic residue. The GXXG sequence was often repeated as GXXGXXG. Two nonameric peptides were synthesized to determine whether or not the peptide inhibits pp60
c−src
tyrosine kinase activity and the importance of the glycine residues within this sequence. The peptide containing glycine had a K

i
of μM, whereas replacing the glycines with proline increased the K

i
value to 3.1 mM.
The nitric oxide synthase of mouse spermatozoa
Authors: Herrero M.B , Goin J.C , Boquet M , Canteros M.G , Franchi A.M , Perez Martinez S , Polak J.M , Viggiano J.M , Gimeno M.A.F
Published: July 2002

Nitric oxide synthase (NOS) was evidenced in mature mouse spermatozoa by means of biochemical techniques and Western blot. During 120 min of incubation, 107 spermatozoa synthesized 7±2 pmol of l‐[14C]citrulline. Besides, l‐citrulline formation depended on the incubation time and on the concentration of l‐arginine present in the incubation medium. Different concentrations of N
G‐nitro‐l‐arginine methyl ester (L‐NAME) but not aminoguanidine, inhibited l‐[14C]citrulline formation. Western‐blot analysis of solubilized sperm proteins revealed a unique band of M
r=140 kDa with the neural, endothelial and inducible NOS antisera tested. These results provide evidence that mature mouse sperm contains a NOS isoform and that spermatozoa have the potential ability to synthesize NO, suggesting a role for endogenous NO on mammalian sperm function.
TPA induces translocation but not down‐regulation of new PKC isoform η in macrophages, MDCK cells and astrocytes
Authors: Chen Ching-Chow , Wang Jia-Kae , Chen Wei-Chyuan
Published: July 2002

New type protein kinase C (PKC) η was found to be expressed in RAW 264.7 and J774A.1 macrophages, Madin‐Darby canine kidney (MDCK) cells and astrocytes by Western blot analysis. Both cytosol and membrane in macrophages and astrocytes express this isoform, however, the expression in the membrane is more abundant than that in the cytosol. On the other hand, only membrane PKCη was detected in MDCK cells. Exposure of the cells to 1 μM TPA for 10 min resulted in the translocation of PKCη from the cytosolic to the membrane fraction. This translocation maintained at a constant level after 1.5, 3, 6 and 24 h TPA treatment. However, another new type PKCδ which expressed in the macrophages and astrocytes was down‐regulated after long‐term (6 and 24 h) TPA treatment. The immunoreactive band of PKCη in J774A.1 macrophages was blocked by the control PKCη antigenic peptide. Incubation of RAW 264.7 macrophages with UTP (1, 10 and 100 μM) resulted in the accumulation of inositol phosphates, indicating the presence of P2 receptor‐coupled PLC pathway in these cells. This natural activator UTP also induced translocation of PKCη from cytosol to the membrane in RAW 264.7 macrophages after 1, 5 or 10 min treatment. Immunofluorescence microscopy revealed that in RAW 264.7 cells, PKCη is located in the cytoplasm organelle, plasma membrane and nuclear envelope. Stimulation of the cells with TPA resulted in translocation to the plasma membrane. This translocation of PKCη was still apparent after 24 h treatment with TPA.
Comparison of control analysis data using different approaches: modelling and experiments with muscle extract
Authors: Puigjaner Joaquim , Raı̈s Badr , Burgos Montse , Comin Begoña , Ovádi Judit , Cascante Marta
Published: July 2002

Experimental and model studies have been performed to characterize the control properties of hexokinase and phosphofructokinase in muscle glycolysis and to examine the nature of error associated with experimental flux control coefficient determinations. Different approaches of metabolic control analysis, classical titration, co‐response analysis and kinetic modelling indicated that flux control coefficients could be reliably estimated experimentally for the upper part of glycolysis. The kinetic parameters applied to construct the mathematical model were determined in muscle extract under similar conditions used for flux studies. If the kinetic parameters of commercial enzymes are introduced into the model the control analysis data cannot be trusted. Co‐response analysis can also be successfully applied to determination of the flux control coefficients of the system. However, the involvement of a rapid‐equilibrium enzyme, such as glucose 6‐phosphate isomerase, could result in estimation errors for the relevant co‐response coefficients that are propagated into the elasticity matrix. If the co‐response coefficients related to isomerase activity are replaced by the values obtained by kinetic modelling, the values of elasticities are correct. Our data also suggest that in the upper part of glycolysis hexokinase mainly controls the pathway flux whereas phosphofructokinase exerts dominant control on the turnover of internal metabolite stocks inside the system.
Purification and characterization of sulfide dehydrogenase from alkaliphilic chemolithoautotrophic sulfur‐oxidizing bacteria
Authors: Sorokin Dimitry Yu , de Jong Govardus A.H , Robertson Lesley A , Kuenen Gijs J
Published: July 2002

Extracts of the alkaliphilic sulfur‐oxidizing autotroph strain AL3 contained sulfide:cytochrome c oxidoreductase. This was active above pH 8, and was associated with the cell membranes. Although up to 60% of the initial activity was lost during Triton X‐100 extraction, further purification resulted in an enzyme that catalyzed sulfide oxidation with horse heart cytochrome c. This enzyme was a 41 kDa protein containing heme c
554. The optimum pH of the membrane bound enzyme was 9.0, but after extraction this fell to 8.0. The enzyme catalyzed a single electron oxidation of HS−. Hydrosulfide radical is therefore the most probable product.
Cellular regulation of prostaglandin H synthase catalysis
Authors: Kulmacz Richard J
Published: July 2002

Prostanoids are a group of potent bioactive lipids produced by oxygenation of arachidonate or one of several related polyunsaturated fatty acids. Cellular prostaglandin biosynthesis is tightly regulated, with a large part of the control exerted at the level of cyclooxygenase catalysis by prostaglandin H synthase (PGHS). The two known isoforms of PGHS have been assigned distinct pathophysiological functions, and their cyclooxygenase activities are subject to differential cellular control. This review considers the contributions to cellular catalytic control of the two PGHS isoforms by intracellular compartmentation, accessory proteins, arachidonate levels, and availability of hydroperoxide activator.
Non‐inhibiting perturbation of the primary energy conversion site (Qo site) in Rhodobacter capsulatus ubihydroquinone:cytochrome c oxidoreductase (cytochrome bc1 complex)
Authors: Sharp R.Eryl , Palmitessa Aimee , Gibney Brian R , Moser Christopher C , Daldal Fevzi , Dutton P.Leslie
Published: July 2002

Ethanol added to Rhodobacter capsulatus chromatophore membranes containing the cytochrome bc
1 complex effectively uncouples the sensitivity of the [2Fe‐2S] cluster EPR spectrum to the number and redox state of ubiquinone/ubihydroquinone within the Qo site. Ethanol has no effect upon the rate of catalysis, leading to a non‐inhibiting perturbation of cytochrome bc
1 function. We suggest that displacement occurs by ethanol acting from the aqueous phase to successfully compete with the Qo site ubiquinones and water to hydrogen bond the NϵH atom(s) of the coordinating [2Fe‐2S] cluster histidines.
The evolution of starch‐binding domain
Authors: Janeček Štefan , Ševčı́k Jozef
Published: July 2002

Amylolytic enzymes belonging to three distinct families of glycosidases (13, 14, 15) contain the starch‐binding domain (SBD) positioned almost exclusively at the C‐terminus. Detailed analysis of all available SBD sequences from 43 different amylases revealed its independent evolutionary behaviour with regard to the catalytic domains. In the evolutionary tree based on sequence alignment of the SBDs, taxonomy is respected so that fungi and actinomycetes form their own separate parts surrounded by bacteria that are also clustered according to taxonomy. The only known N‐terminal SBD from Rhizopus oryzae glucoamylase is on the longest branch separated from all C‐terminal SBDs. The 3‐dimensional (3‐D) structures of fungal glucoamylase and bacterial CGTase SBDs are compared and used to discuss the interesting SBD evolution.
Somatostatin inhibits PDGF‐stimulated Ras activation in human neuroblastoma cells
Authors: Cattaneo Maria Grazia , Scita Giorgio , Vicentini Lucia M.
Published: July 2002

The main physiological role of somatostatin (SST) is the control of hormone secretion. Recently, SST has been shown to exert antiproliferative effects on some human tumors via both direct and indirect mechanisms. We have previously found that in the human neuroblastoma cell line SY5Y the SST analogue lanreotide (BIM 23014) inhibited serum‐stimulated cell proliferation and MAP kinase activity. Here, we examine the effect of SST on PDGF‐induced Ras activation. We found that SST suppressed PDGF‐induced Ras activation in a pertussis toxin (PTx)‐independent and peroxovanadate‐dependent manner. Ras‐specific GTPase activating protein (GAP) activities were not altered by SST treatment. On the contrary, PDGF‐induced PDGF receptor phosphorylation was decreased by SST in a PTx‐independent, peroxovanadate‐dependent manner, likely accounting for the SST‐mediated inhibition of PDGF‐induced Ras activation.
Subcellular trafficking abnormalities of a prion protein with a disrupted disulfide loop
Authors: Yanai Anat , Meiner Zeev , Gahali Inbar , Gabizon Ruth , Taraboulos Albert
Published: July 2002

The single disulfide loop (Cys178‐Cys213) of the prion protein (PrP) may stabilize the conformation of this protein by bridging the C‐terminal α‐helices. The substitution mutant Cys178Ala fails to form the prion isoform PrPSc when expressed in scrapie‐infected neuroblastoma ScN2a cells (Muramoto et al., Proc. Natl. Acad. Sci. USA 93, 15457–15462). To investigate the reasons for this failure, we introduced the C178A substitution in the full length mouse PrP gene as well as in its N‐terminally truncated Δ23‐88 version. The resulting mutants (C178A and ΔC178A, respectively) were transiently expressed in N2a and CHO cells. Wild‐type PrP, wild‐type Δ23‐88 and the point mutant E199K served as controls in these experiments. Compared to the wild‐type controls, the C178A mutants were markedly resistant to proteolysis and they were also vastly insoluble in sarcosyl. Studying the metabolic fate of the C178A mutants, we found that in contrast to control PrP molecules, these mutants (i) remained sensitive to the diagnostic endoglycosidase EndoH, (ii) failed to reach the cell surface and (iii) congregated in large juxtanuclear spots. We surmise that these severe trafficking abnormalities may contribute both to the spontaneous aggregation of the C178A mutants and to their reported inability to form PrPSc.
Transient expression assays with the proximal promoter of a newly characterized actin gene from the oyster Crassostrea gigas
Authors: Cadoret J.-P. , Debón R. , Cornudella L. , Lardans V. , Morvan A. , Roch P. , Boulo V.
Published: July 2002

We undertook the characterization of an actin gene and its proximal promoter in the oyster Crassostrea gigas. A complete actin cDNA was identified, sequenced and its amino acid sequence deduced. Comparative analysis showed a high homology with actin of other species and that this gene is closer to the cytoplasmic form of actins than to the muscle type. A probe derived from the 5′‐untranslated region of the cDNA was then used to isolate the actin gene from a genomic library. The gene was sequenced and shown to contain a single 643 bp intron. A 1670 bp fragment upstream from the open reading frame was isolated and sequenced. This upstream region displays typical features of actins such as a serum response element (CarG box). This fragment was cloned into the promoterless vector pGL3‐basic and the resulting construct was transfected into cells of dissociated oyster heart primary cultures. Its capacity to express the luciferase in this in vitro homologous system was monitored and showed high expression levels. This is the first complete actin sequence reported so far for the oyster C. gigas and its promoter is the first available among bivalves.
Glucose degradation product methylglyoxal enhances the production of vascular endothelial growth factor in peritoneal cells: role in the functional and morphological alterations of peritoneal membranes in peritoneal dialysis
Authors: Inagi Reiko , Miyata Toshio , Yamamoto Takashi , Suzuki Daisuke , Urakami Ken-ichi , Saito Akira , van Ypersele de Strihou Charles , Kurokawa Kiyoshi
Published: July 2002

Peritoneal membrane permeability deteriorates in peritoneal dialysis (PD) patients. We test whether glucose degradation products (GDPs) in PD fluids, glyoxal, methylglyoxal and 3‐deoxyglucosone, stimulate the production of vascular endothelial growth factor (VEGF), a factor known to enhance vascular permeability and angiogenesis. VEGF increased in cultured rat mesothelial and human endothelial cells exposed to methylglyoxal, but not to glyoxal or 3‐deoxyglucosone. VEGF also increased in peritoneal tissue of rats given intraperitoneally methylglyoxal. VEGF and carboxymethyllysine (CML) (formed from GDPs) co‐localized immunohistochemically in mesothelial layer and vascular walls of the peritoneal membrane of patients given chronic PD. By contrast, in the peritoneum of non‐uremic subjects, VEGF was identified only in vascular walls, in the absence of CML. VEGF production induced by GDPs may play a role in the progressive deterioration of the peritoneal membrane.
Hormone replacement therapy to improve left ventricular diastolic functions in healthy postmenopausal women
Authors: Yildirir A , Yarali H , Kabakci G , Aybar F , Akgul E , Bukulmez O
Published: July 2002

Objectives: To investigate the effects of estrogen and estrogen plus progesterone replacement therapy on left ventricular systolic and diastolic function parameters in healthy postmenopausal women. Methods: Forty‐six healthy consecutive postmenopausal women were prospectively enrolled. Hormone replacement therapy (HRT), which was either 0.625 mg/day conjugated equine estrogen (CEE) alone, or with 2.5 mg/day medroxyprogesterone acetate (MPA) was administered depending on the hysterectomy status. Left ventricular systolic and diastolic function parameters were evaluated with echocardiography before and after 6 months of HRT. The paired t‐test was used for statistical analysis. Results: Estrogen or estrogen plus progesterone did not significantly alter the left ventricular dimensions and systolic function parameters. However, significant improvements were noted in several diastolic function parameters including late diastolic mitral flow velocity, ratio of early to late mitral flow velocity and isovolumic relaxation time (P=0.003, P=0.001 and P=0.005, respectively, for the CEE group; all P<0.001 for the CEE+MPA group). Conclusions: Estrogen or estrogen plus progesterone replacement therapy may significantly improve left ventricular diastolic functions in healthy postmenopausal women.
Barriers to uptake and use of modern methods of contraception in developing countries
Authors: Konje J.C. , Ladipo O.A.
Published: July 2002

As the next millennium approaches, the current world population of 5.9 billion will continue to increase by 81 million per year — 93% of which will come from the developing countries. Poor uptake and utilisation of various modern methods of contraception in the developing countries is mainly responsible. In this article, we identify various barriers responsible for the low prevalence of contraceptive uptake in these countries and suggest how these barriers may be eliminated. We conclude that by increasing contraceptive availability and utilisation, population explosion can be significantly controlled.
A 10‐year follow‐up study of contraceptive Norplant implants
Authors: Du M.K. , Chow L.P. , Zheng H.M. , Chen C.H.C.
Published: July 2002

Objectives: To evaluate the long‐term efficacy and health problems associated with Norplant implants and re‐implants after 5 full years of first implants. Method: From 1984 to 1988, 1657 women accepted first implants of Type I and Type II of Norplant, and 394 first acceptors had a re‐implant, at a clinic for study. The clinical records and annual follow‐up data of acceptors were analyzed. The life‐table technique was the main method used. Results: The continuation rates were very high. The cumulative pregnancy rates at 1, 3 and 5 full years of use were 0.0%, 0.1% and 0.7%, respectively. Users with heavier body weight had higher pregnancy rates. The rate of menstrual disturbances peaked at 73% after 3 months and consistently decreased to 20% at 5 years of use. Rates of menstrual disturbances associated with re‐implants were much lower. Conclusion: Norplant is extremely effective and safe for long‐term use.
Bilateral asymmetry of the inositol trisphosphate‐mediated calcium signaling in two‐cell ascidian embryos
Authors: Albrieux Mireille , Villaz Michel
Published: July 2002

In ascidian oocytes, numerous calcium signaling events occur at fertilization which contribute to resume and complete meiosis, and determine the three embryonic axes. The main ooplasmic and intracellular calcium channels at work in the calcium signaling of the one‐cell embryo have different roles and fates when the first mitosis begins. By whole‐cell patch‐clamp recording, we observed different families of these calcium channels in the blastomeres of Phallusia mammillata two‐cell ascidian embryos. Membrane capacitance has been measured to evaluate the oocyte and blastomere surface area, allowing certification of the exact time of cell division. At the two‐cell stage, no difference was observed in the density of voltage‐dependent calcium channels in each blastomere, or in the ryanodine‐sensitive calcium stores. In contrast, a bilateral asymmetry was recorded for the ooplasmic channels responsible for calcium entry after calcium store depletion: they could be activated only in the blastomere not wearing the polar bodies. The same laterality was observed in the InsP3‐induced internal calcium release. Moreover, this asymmetry included a one‐way communication in the InsP3‐dependent calcium signaling between the two blastomeres. These results enhance the understanding of the early steps of development, and underscore the interest for ascidians in studies of polarity patterning.
Isolation of the major basic nuclear protein and its localization on chromosomes of the dinoflagellate, Oxyrrhis marina
Authors: Kato Koichi H , Moriyama Akihiko , Huitorel Philippe , Cosson Jacky , Cachon Monique , Sato Hidemi
Published: July 2002

Basic nuclear proteins were extracted from isolated nuclei of Oxyrrhis marina. The HPLC pattern of the extract showed a single major peak, which consisted of a major band with an apparent molecular mass of 23 kDa on an SDS‐PAGE gel. We designated this protein as Np23 because of its apparent molecular mass. The amino acid composition of this protein revealed its extremely basic nature with a high lysine content. Polyclonal antibodies were raised against Np23. Immunofluorescence microscopy showed that Np23 was localized within the nucleus of dividing and non‐dividing cells as well, and immuno‐electron microscopy showed that the protein was localized only on chromosomes. These data established that Np23 is the major basic chromosome protein of Oxyrrhis marina.
Factors influencing the validity of relatives' reports about symptoms of first-episode schizophrenia
Authors: Hambrecht M
Published: July 2002

Valid information on the early course of schizophrenia is necessary for clinical and research purposes, for example, to determine the onset of the disorder. Since reports given by psychotic patients are questionable, relatives are often asked about their observations. In order to test the quality of these reports, the recollections of emerging symptomatology were assessed systematically from 30 recent onset, postpsychotic schizophrenic patients and from 69 informants (mostly their close relatives) by means of the Interview for the Retrospective Assessment of the Onset of Schizophrenia (IRAOS). Patient-informant agreement rates like kappa were compared between the relatives of every single case. Multiple regression analyses demonstrated that personality and attributional factors, particularly causal attributions and the image the informant has about him/herself and about the patient, determine the quality of the informants' reports. Highest kappas over all symptoms, for instance, were reached by relatives who described the patient as “dominant” and themselves as “reserved”, and who attributed the disease to current psychosocial stress. Long and close contact to the patient tends to impair the quality of reports.
The Nordic comparative study on sectorized psychiatry: characteristics of repeat users of emergency outpatient services in two Nordic psychiatric services. A 1-year follow-up study
Authors: Saarento O , Kastrup M , Hansson L
Published: July 2002

To characterise frequent use of psychiatric emergency outpatients services, this paper reports results from a prospective investigation of use of psychiatric services by new patients in two Nordic psychiatric services, Frederiksberg in Denmark and Oulu in Finland. One year treated incidence cohorts were used. Total number of patients included was 1,055. The repeat user was defined as a patient having at least three emergency outpatient contacts during a 1-year follow-up. The repeat users constituted 15.8% of the sample and 70.8% of all the emergency contacts in Frederiksberg. In Oulu the respective figures were 9.3% and 33.8%. The number of planned outpatient contacts or the number of hospital admissions of the repeat users did not differ from the non-repeaters. Repeaters in Frederiksberg were more likely to be self-referrals, male, divorced or unmarried, living with their parents, without their own housing, unemployed, aged between 25 and 44 years, and to have a diagnosis of dependency or personality disorder. In Oulu they did not differ from the other patients with regard to sociodemographic or diagnostic characteristics.
Psychometric qualities of the French version of the Heinrichs quality of life rating scale
Authors: Simon-Abbadi S. , Guelfi J.D. , Ginestet D.
Published: July 2002

The quality of life concept has been increasingly used as a major tool for patient care and clinical investigations. The Heinrichs quality of life scale (QLS) is the quality of life assessment method widely used in schizophrenic patients. The QLS was translated into its French version by J.D.Guelfi according the back-translation method. This version of the validation study included 60 schizophrenic inpatients. The scale possesses acceptable psychometric qualities. The test-retest reliability is good for nearly all items of the scale and for the categories and overall score. The internal consistency alpha-coefficients were 0.9 for the global score and varied between 0.6 and 0.9 according to the category. Factor analysis elicited four factors. Convergent validity is good. Recommendations for future use of the QLS are proposed.
Factors associated with vascular and neurological complications of hand-arm vibration syndrome among tire shop workers in Kelantan, Malaysia
Authors: Qamruddin Asraf A , Nik Husain Nik Rosmawati , Sidek Mohd Y , Hanafi Muhammad H , Mohd Ripin Zaidi
Published: May 2021

Objective

Prolonged exposure to hand-arm vibration (HAV) at the workplace is associated with hand-arm vascular syndrome (HAVS). This study aimed to determine the prevalence and the factors associated with the vascular and neurological complications of HAVS among tire shop workers in Kelantan, Malaysia.

Methods

A cross-sectional study involving 200 tire shop workers from two districts in Kelantan was conducted. Data were collected at the field using Malay Translated HAVS questionnaire, and hand-arm vibration was measured. Multiple logistic regression analysis was used to determine the associated factors.

Results

The prevalence of vascular and neurological complications of HAVS among the tire shop workers was 12.5% (95% CI: 10.16, 14.84) and 37.0% (95% CI: 30.31, 43.69), respectively. From multiple logistic regression analysis, only A(8) of HAV exposure was significantly associated with the development of vascular complications and A(8) of HAV exposure, age. and body mass index were significantly associated with the development of neurological complications of HAVS.

Conclusion

This study has identified that HAVS is a significant problem among workers exposed to HAV in a warm environment. A(8) of HAV exposure is significantly associated with the development of both vascular and neurological complications. Therefore, there is a need for better control of vibration exposure in Malaysia.
Progress in housing policy research activity in Dōjunkai: A study on the discussion and research in the process of establishing housing policy during World War II (2)
Authors: Horiuchi Keisuke , Nakae Ken
Published: May 2021

Dōjunkai was a nonprofit government foundation set up in 1924 to rebuild the areas hardest hit by the Great Kantō Earthquake of 1923. In the late 1930s, Dōjunkai established the Housing Policy Research Committee (HPRC). Previous studies have pointed out the importance of the research activity of this committee and demonstrated that some of its findings shaped the housing policy of wartime and postwar Japan. Less well known are the circumstances in which Dōjunkai became increasingly involved in policy research. This article is distinctive in that it examines Dōjunkai's research within a broad temporal lens, beginning with the founding of the corporation, and in doing so, it analyzes the circumstances in which the HPRC was established. Two novel findings are revealed: 1. Dōjunkai increasingly developed an organizational footing for research after establishing the Research Section and launching a research series titled, “Research into Building and Maintenance of Small Houses.” 2. Having accumulated a body of findings on the housing policies of foreign governments, Dōjunkai established the HPRC because the relevant government ministry lacked its own organizational apparatus for researching housing policy.
Validation of accuracy deformable image registration contour propagation using a benchmark virtual HN phantom dataset
Authors: Boyd Robert , Basavatia Amar , Tomé Wolfgang A.
Published: May 2021

Virtual anatomic phantoms offer precise voxel mapping of the variation of anatomy with ground truth deformation vector fields (DVFs). Dice similarity coefficient (DSC) and mean distance to agreement (MDA) are the standard metrics for evaluating geometric contour congruence when testing deformable registration (DIR) algorithms. A HN virtual patient phantom data set was used for a kVCT‐kVCT automatic propagation contour validation study employing the Accuray DIR algorithm. Furthermore, since TomoTherapy uses MVCT images of the relevant anatomy for adaptive monitoring, the kVCT image data set quality was transformed to an MVCT image data set quality to study intermodal kVCT‐MVCT DIR accuracy. The results of the study indicate that the Accuray DIR algorithm can be expected to autopropagate HN contours adequately, on average, within tolerances recommended by TG‐132 (DSC 0.8‐0.9, MDA within voxel width). However, contours critical to dosimetric planning should always be visually proofed for accuracy. Using standard reconstruction MVCT image quality causes slightly less, but acceptable, agreement with ground truth contours.
Substrate‐Versatile Direct‐Write Printing of Carbon Nanotube‐Based Flexible Conductors, Circuits, and Sensors
Authors: Owens Crystal E. , Headrick Robert J. , Williams Steven M. , Fike Amanda J. , Pasquali Matteo , McKinley Gareth H. , Hart A. John
Published: May 2021

Manufacturing of printed electronics relies on the deposition of conductive liquid inks, typically onto polymeric or paper substrates. Among available conductive fillers for use in electronic inks, carbon nanotubes (CNTs) have high conductivity, low density, processability at low temperatures, and intrinsic mechanical flexibility. However, the electrical conductivity of printed CNT structures has been limited by CNT quality and concentration, and by the need for nonconductive modifiers to make the ink stable and extrudable. This study introduces a polymer‐free, printable aqueous CNT ink, and, via an ambient direct‐write printing process, presents the relationships between printing resolution, ink rheology, and ink‐substrate interactions. A model is constructed to predict printed feature sizes on impermeable substrates based on Wenzel wetting. Printed lines have conductivity up to 10 000 S m−1. The lines are flexible, with <5% change in DC resistance after 1000 bending cycles, and <3% change in DC resistance with a bending radius down to 1 mm. Demonstrations focus on i) conformality, via printing CNTs onto stickers that can be applied to curved surfaces, ii) interactivity using a CNT‐based button printed onto folded paper structure, and iii) capacitive sensing of liquid wicking into the substrate itself. Facile integration of surface mount components on printed circuits is enabled by the intrinsic adhesion of the wet ink.
Maskless Preparation of Spatially‐Resolved Plasmonic Nanoparticles on Polydimethylsiloxane via In Situ Fluoride‐Assisted Synthesis
Authors: Mariani Stefano , La Mattina Antonino Amedeo , Paghi Alessandro , Strambini Lucanos , Barillaro Giuseppe
Published: May 2021

Here, a fluoride‐assisted route for the controlled in‐situ synthesis of metal nanoparticles (NPs) (i.e., AgNPs, AuNPs) on polydimethylsiloxane (PDMS) is reported. The size and coverage of the NPs on the PDMS surface are modulated with time and over space during the synthetic process, leveraging the improved yield (10×) and faster kinetics (100×) of NP formation in the presence of F−ions, compared to fluoride‐free approaches. This enables the maskless preparation of both linear and step gradients and patterns of NPs in 1D and 2D on the PDMS surface. As an application in flexible plasmonics/photonics, continuous and step‐wise spatial modulations of the plasmonic features of PDMS slabs with 1D and 2D AgNP gradients on the surface are demonstrated. An excellent spatially resolved tuning of key optical parameters, namely, optical density from zero to 5 and extinction ratio up to 100 dB, is achieved with AgNP gradients prepared in AgF solution for 12 minutes; the performance are comparable to those of commercial dielectric/interference filters. When used as a rejection filter in optical fluorescence microscopy, the AgNP‐PDMS slabs are able to reject the excitation laser at 405 nm and retain the green fluorescence of microbeads (100 µm) used as test cases.
A One‐Pot Universal Approach to Fabricate Lubricant‐Infused Slippery Surfaces on Solid Substrates
Authors: Tesler Alexander B. , Prado Lucia H. , Khusniyarov Marat M. , Thievessen Ingo , Mazare Anca , Fischer Lena , Virtanen Sannakaisa , Goldmann Wolfgang H. , Schmuki Patrik
Published: May 2021

Wetting is a surface phenomenon that commonly occurs in nature and has an enormous influence on human life. Slippery liquid‐infused porous surfaces have recently been developed to support the growing demand for anti‐fouling coatings. While short‐chain fluorinated compounds, commonly used to reduce the surface energy of substrates, are banned due to environmental toxicity, silane‐based compounds are expensive and barely scalable. In this sense, silicone‐based chemistry may match the gap as a real alternative. However, the grafting approaches demonstrated so far suffered from either slow binding kinetics or are applied under harsh conditions. Here, it is demonstrated that polydimethylsiloxanes graft to virtually any substrate when illuminated by UV light serving simultaneously as a reducing surface energy agent and infusing lubricant. This procedure is applied on metals, metal oxides, and ceramics of various surface morphologies. The proposed approach is simple, fast, scalable, environmentally friendly, and of low‐cost, yet forms stable lubricant‐infused slippery surfaces by a one‐pot process. Due to the biocompatibility of silicone‐based compounds, the process is examined on plain medically applicable substrates such as scalpel blades and glass lenses that display enhanced corrosion resistance, reduced friction through incision, and repel blood staining and bacterial adhesion without deteriorating their mechanical and optical characteristics.
Interfacial Engineering of Nickel Hydroxide on Cobalt Phosphide for Alkaline Water Electrocatalysis
Authors: Yu Xiaowen , Zhao Jun , Johnsson Mats
Published: May 2021

Catalysts based on earth‐abundant non‐noble metals are interesting candidates for alkaline water electrolysis in sustainable hydrogen economies. However, such catalysts often suffer from high overpotential and sluggish kinetics in both the hydrogen and oxygen evolution reactions (HER and OER). In this study, a hybrid catalyst made of iron‐doped cobalt phosphide (Fe‐CoP) nanowire arrays and Ni(OH)2 nanosheets is introduced that displays strong electronic interactions at the interface, which significantly improves the interfacial reactivity of reactants and/or intermediates with the hybrid catalyst surface. The combined experimental and theoretical study further confirms that the hybrid catalyst promotes the sluggish rate‐limiting steps in both the HER and OER. Full water electrolysis is thus enabled to take place at such a low cell voltage as 1.52 V to reach the current density of 10 mA cm−2 along with superior durability and high conversion efficiency.
2D Honeycomb‐Kagome Polymer Tandem as Effective Metal‐Free Photocatalysts for Water Splitting
Authors: Jing Yu , Zhou Zhenpei , Geng Weixiang , Zhu Xinyue , Heine Thomas
Published: May 2021

On the basis of first‐principles calculations, the potential of applying 2D honeycomb‐kagome polymers made of heteroatom‐centered triangulene derivatives to photocatalyze water splitting is explored. The designed 2D polymers possess indirect bandgaps in the range of 1.80–2.84 eV and show pronounced light absorption in the ultraviolet and visible region of the solar spectrum. With suitable band edge alignment, the examined N‐ and B‐center polymers can generate sufficient photon‐excited electrons and holes to activate the hydrogen and oxygen evolution reactions, respectively. The combination of lattice‐inherent band features (flat bands) with chemical functionalization (potential shift due to heteroatoms) makes it possible to construct tandem cells with suppressed electron/hole recombination for effective overall water splitting. In addition, there is a potential difference between the half‐electrodes that can be utlized to power​ auxiliary components in self‐sufficient photocatalyzers.
Long‐Persistent Luminescence from an Exciplex‐Based Organic Light‐Emitting Diode
Authors: Tan Shinichi , Jinnai Kazuya , Kabe Ryota , Adachi Chihaya
Published: May 2021

Organic long‐persistent luminescent systems (OLPLs) exhibiting long‐lasting emission after photoexcitation consist of organic electron donors and acceptors, that are widely used in organic light‐emitting diodes (OLEDs). Although OLPLs and OLEDs include very similar excitonic processes, long‐lasting emission has never been observed in OLEDs. This study confirms the presence of long‐persistent luminescence (LPL) under electrical excitation.