bluuebunny/crossref_metadata_2025 huggingface dataset:
Strategies for Landslide Disaster Mitigation in Baktiraja’s Tourism Zones, Humbang Hasundutan Regency, Indonesia
Authors: Sitompul Astri Handayani , Toha Achmad Siddik , Slamet Bejo
Published: January 2024

Mitigation disaster is very important to develop region in many areas. This study addresses landslide mitigation for tourism development in the Baktiraja District, Humbang Hasundutan Regency. Four parameters, including slope inclination, rainfall, soil type, and land use, reveal four levels of landslide vulnerability: low, moderate, high, and very high. The method in this study used spatial analysis using ArcGIS (Geographic Information Systems) 10.8 identifies Tipang Village, Simangulampe Village, and Marbun Tonga Marbun Dolok Village as areas with the highest vulnerability, covering 77.60% of the Baktiraja District. MSP+DM analysis categorizes the tourism potential in these villages as "Embryonic." To elevate this status to "Growing" and "Self-sustaining," emphasis on improving marketability indicators through enhanced packaging, diverse promotional models, and an extensive marketing network is needed. Sustainable development efforts by the local government and active community participation in preserving local wisdom, natural attractions, and cultural heritage are crucial. Recommendations include regular updates on disaster vulnerability data, establishment of evacuation routes and shelters, early warning systems, and community training. Regulations on open land use for physical development need attention, and the government should allocate budget for tourism infrastructure. Ensuring synergy among the government, local community, and tourism stakeholders is key to sustainable tourism development in this area.
Effects of Water Deficit Stress at the Tillering Stage of Direct Seeded Rice (Oryza sativa L.)
Authors: Kant Kamal , Baraiya Shubham J. , Srivastva Alok , Karmakar Nilima , Narwade Ajay V. , Patel P. B.
Published: January 2024

The ten rice varieties viz. NAUR-1, Purna, GNR-6, NVSR-2227, NVSR-3093, NVSR-2285, NVSR-2278, NVSR-2852, NVSR-2601, and NVSR-2927 were grown in kharif season for observing their efficiency in terms of yield under a deficit of water at tillering stage. The effects of short-term water stress on various morpho-physiological and biochemical traits viz. leaf area index, number of panicles, chlorophyll content, number of stomata, relative water content, abscisic acid, proline, glycine betaine, ascorbic acid, and harvest index content were studied and they were observed higher in Purna as compared to other nine varieties. However, Plant height and Ionic leakage were recorded lower in Purna as compared to other varieties. The abscisic acid as well as proline and glycine betaine content recorded maximum in Purna which might help in keeping hydration in cells during water deficit stress. Thus, with short-term water deficit stress at tillering stage, the variety Purna would be better in terms of breeding for tolerant variety as well as yield among ten rice varieties.
Haematological Perturbations in Human Immunodeficiency Virus (HIV) Positive Patients Receiving Antiretroviral Therapy in Edo State, Nigeria
Authors: Chikezie K. , Uche C. L. , Ekeleme N. C. , Okite U. P. , Abali I. O. , Jibiro P. , Airaodion A. I.
Published: January 2024

Aim: This study sought to investigate the haematological perturbations in HIV-positive patients undergoing antiretroviral therapy (ART) in Edo State, Nigeria.

Methodology: This cross-sectional case-controlled study was conducted at the HIV clinic of the University of Benin Teaching Hospital. The research enrolled 150 HIV-positive patients and an equal number of sex and age-matched HIV-negative control subjects. Inclusion criteria encompassed individuals aged 18 years and older, confirmed HIV-positive, and receiving ART for at least six months. Exclusion criteria excluded those with sickle cell disorder, recent transfusions, or ongoing sepsis/malaria. Data collection involved self-administered questionnaires, HIV diagnosis via WHO-approved Nigerian National testing algorithms, and comprehensive haematological assessments. The obtained data were analysed using SPSS software, employing descriptive statistics and t-tests with a significance level of 0.05.

Results: Results revealed significant differences in demographic variables, duration of HIV infection, smoking history, and alcohol consumption between HIV-positive patients and control subjects. Furthermore, CD4+ T lymphocyte counts showed substantial variations, indicating immunological differences. Haematological parameters such as haemoglobin levels, packed cell volume, white blood cell, platelet counts, and erythrocyte sedimentation rate exhibited statistically significant differences between the two groups. Additionally, a sub-analysis of HIV-positive patients based on CD4+ T lymphocyte counts highlighted specific haematological changes associated with varying immunological statuses.

Conclusion: The findings underscore the impact of HIV and ART on haematological parameters, emphasizing the need for comprehensive monitoring and management strategies. This research contributes valuable insights into the context of HIV management in Nigeria, aiding healthcare professionals in optimizing patient care.
Parametric Analysis on Formability of SS304 Metal Bipolar Plate with Wave Flow Field Structure
Authors: Jiahao Feng , Pengyan Guo , Cunwu He , Chengwei Liu
Published: January 2024

The main production method of metal bipolar plate is stamping, and the size parameters of the flow field structure can not only change the performance of the fuel cell, but also affect the stamping quality of the metal bipolar plate. In the case of ensuring the performance of the fuel cell, it is necessary to study the stamping of the metal bipolar plate with different flow field structures. In the past, there were few studies on the wave flow field stamping forming. This paper analyzed the wave flow field, formulated several sets of bipolar plate structural dimension parameters, and evaluated the stamping forming quality of the reaction zone of SS304 metal bipolar plate through finite element simulation. By reducing the rib height ΔH=0.075mm in the corner part, the maximum thinning rate can be reduced from 34.833% to 24.689% and the thickness can reach 0.0753mm when the flow channel width S=1.0mm, the rib width W=1.5mm and the forming depth H=0.5mm. It provides some guidance for optimizing the structural dimension parameters of metal bipolar plates.
Efficacy and Safety of Unani Formulation in Loss of Appetite
Authors: Huma  , Habib Arif , Iqbal Arsheed , Zahoor  , Arjumand  , Sabia
Published: January 2024

Aims and Objectives: Loss of appetite (LOA) impacts individual well-being and quality of life. It can contribute to weight loss and nutritional deficiencies, and associated poor healthcare outcomes, including increased mortality. This study presents the efficacy and safety of Unani pharmacopeia formulation. Habb-e-TurshMushtahi in loss of appetite (Anorexia).

Study Design: Open-labelled, single arm, clinical trial.

Materials and Methods: The study was conducted on 100 patients having the complaint of loss of appetite; Patients of either sex in the age group of 18 to 65years and decreased appetite with SNAC ≤14 were included in the study. The treatment was given for two weeks and safety assessment was done before and after end of treatment. P-value 0.05 was considered significant. 

Results: Females were almost double than men who were suffered with the disease. The considered parameters show a good response p < 0.05 after the intervention of Unani pharmacopoeial formulation in both genders. In case of safety parameters, no significance p>0.05 has been seen for pathological and biochemical investigations.

Conclusion: The management for the loss of appetite can be easily treated with the unani drug which is effective for the rapid relief without any adverse effect.
Protein kinase C- and calcium-regulated pathways independently synergize with Gi pathways in agonist-induced fibrinogen receptor activation
Authors: QUINTON Todd M. , KIM Soochong , DANGELMAIER Carol , DORSAM Robert T. , JIN Jianguo , DANIEL James L. , KUNAPULI Satya P.
Published: November 2002

Platelet fibrinogen receptor activation is a critical step in platelet plug formation. The fibrinogen receptor (integrin αIIbβ3) is activated by agonist-mediated Gq stimulation and resultant phospholipase C activation. We investigated the role of downstream signalling events from phospholipase C, namely the activation of protein kinase C (PKC) and rise in intracellular calcium, in agonist-induced fibrinogen receptor activation using Ro 31-8220 (a PKC inhibitor) or dimethyl BAPTA [5,5′-dimethyl-bis-(o-aminophenoxy)ethane-N,N,N′,N′-tetra-acetic acid], a high-affinity calcium chelator. All the experiments were performed with human platelets treated with aspirin, to avoid positive feedback from thromboxane A2. In the presence of Ro 31-8220, platelet aggregation caused by U46619 was completely inhibited while no effect or partial inhibition was seen with ADP and the thrombin-receptor-activating peptide SFLLRN, respectively. In the presence of intracellular dimethyl BAPTA, ADP- and U46619-induced aggregation and anti-αIIbβ3 antibody PAC-1 binding were completely abolished. However, similar to the effects of Ro 31-8220, dimethyl BAPTA only partially inhibited SFLLRN-induced aggregation, and was accompanied by diminished dense-granule secretion. When either PKC activation or intracellular calcium release was abrogated, aggregation and fibrinogen receptor activation with U46619 or SFLLRN was partially restored by additional selective activation of the Gi signalling pathway. In contrast, when both PKC activity and intracellular calcium increase were simultaneously inhibited, the complete inhibition of aggregation that occurred in response to either U46619 or SFLLRN could not be restored with concomitant Gi signalling. We conclude that, while the PKC- and calcium-regulated signalling pathways are capable of inducing activating fibrinogen receptor independently and that each can synergize with Gi signalling to cause irreversible fibrinogen receptor activation, both pathways act synergistically to effect irreversible fibrinogen receptor activation.
Enhancement of iron toxicity in L929 cells by d-glucose: accelerated(re-)reduction
Authors: LEHNEN-BEYEL Ilka , GROOT Herbert de , RAUEN Ursula
Published: November 2002

It has recently been shown that an increase in the cellular chelatable iron pool is sufficient to cause cell damage. To further characterize this kind of injury, we artificially enhanced the chelatable iron pool in L929 mouse fibroblasts using the highly membrane-permeable complex Fe(III)/8-hydroxyquinoline. This iron complex induced a significant oxygen-dependent loss of viability during an incubation period of 5h. Surprisingly, the addition of d-glucose strongly enhanced this toxicity whereas no such effect was exerted by l-glucose and 2-deoxyglucose. The assumption that this increase in toxicity might be due to an enhanced availability of reducing equivalents formed during the metabolism of d-glucose was supported by NAD(P)H measurements which showed a 1.5—2-fold increase in the cellular NAD(P)H content upon addition of d-glucose. To assess the influence of this enhanced cellular reducing capacity on iron valence we established a new method to measure the reduction rate of iron based on the fluorescent iron(II) indicator PhenGreen SK. We could show that the rate of intracellular iron reduction was more than doubled in the presence of d-glucose. A similar acceleration was achieved by adding the reducing agents ascorbate and glutathione (the latter as membrane-permeable ethyl ester). Glutathione ethyl ester, as well as the thiol reagent N-acetylcysteine, also caused a toxicity increase comparable with d-glucose. These results suggest an enhancement of iron toxicity by d-glucose via an accelerated (re-)reduction of iron with NAD(P)H serving as central electron provider and ascorbate, glutathione or possibly NAD(P)H itself as final reducing agent.
Regulation of the 14-3-3-binding protein p39 by growth factors and nutrients in rat PC12 pheochromocytoma cells
Authors: HARTHILL Jean E. , RUBIO Mercedes POZUELO , MILNE Fiona C. , MacKINTOSH Carol
Published: November 2002

Unstimulated PC12 pheochromocytoma cells contain many proteins that bound to 14-3-3s in competition with a 14-3-3-binding peptide. Additional proteins, including one of 39kDa (p39), became capable of binding to 14-3-3s in phosphatidylinositol 3-kinase-dependent responses to epidermal growth factor or nerve growth factor in vivo. The growth factor regulation was unaffected by inhibitors of the mitogen- or stress-activated protein kinase pathways, or by glucose starvation, but was blocked by amino acid starvation and only partially blocked by rapamycin. p39 in extracts of unstimulated, nutrient-fed cells, but not nutrient-starved cells, was able to bind to 14-3-3s after phosphorylation by protein kinase B (PKB) in vitro. Nutrient starvation did not affect the growth factor-stimulated activation of PKB in vivo. Either cycloheximide (CHX) or the cysteine protease inhibitor, MG132, restored the responsiveness of p39 to growth factors in nutrient-starved cells. In contrast, MG132 could not replace amino acids in supporting the growth factor-stimulated phosphorylation of two downstream targets of mTOR (mammalian target of rapamycin), namely eukaryotic initiation factor 4E binding protein 1 (4E-BP1) and p70 S6 kinase. CHX permitted complete growth factor-stimulated phosphorylation of both 4E-BP1 and p70 S6 kinase in nutrient- starved cells; however, unlike p39, phosphorylation of these proteins was blocked by rapamycin. These findings implicate PKB (or an enzyme with similar specificity) in the growth factor-triggered phosphorylation of p39. In addition, amino acidstarvation induces a CHX- and MG132-sensitive pathway that targets p39 and appears to be distinct from the mechanism of regulation of 4E-BP1 and p70 S6 kinase.
Protein kinase A translocation and insulin secretion in pancreatic β-cells: studies with adenylate cyclase toxin from Bordetella pertussis
Authors: GAO Zhiyong , YOUNG Robert A. , TRUCCO Matteo M. , GREENE Scott R. , HEWLETT Erik L. , MATSCHINSKY Franz M. , WOLF Bryan A.
Published: November 2002

Activation of protein kinase A (cAMP-dependent protein kinase; PKA) triggers insulin secretion in the β-cell. Adenylate cyclase toxin (ACT), a bacterial exotoxin with adenylate cyclase activity, and forskolin, an activator of adenylate cyclase, both dose-dependently increased insulin secretion in the presence, but not the absence, of glucose in insulin-secreting βTC3 cells. The stimulation of cAMP release by either agent was dose-dependent but glucose-independent. Omission of extracellular Ca2+ totally abolished the effects of ACT on insulin secretion and cytosolic cAMP accumulation. ACT and forskolin caused rapid and dramatic increases in cytosolic Ca2+, which were blocked by nifedipine and the omission of extracellular Ca2+. Omission of glucose completely blocked the effects of forskolin and partially blocked the effects of ACT on cytosolic Ca2+. PKA α, β and γ catalytic subunits (Cα, Cβ and Cγ respectively) were identified in βTC6 cells by confocal microscopy. Glucose and glucagon-like polypeptide-1 (GLP-1) caused translocation of Cα to the nucleus and of Cβ to the plasma membrane and the nucleus, but did not affect the distribution of Cγ. In conclusion, glucose and GLP-1 amplify insulin secretion via cAMP production and PKAβ activation.
Oxidative damage and phospholipid fatty acyl composition in skeletal muscle mitochondria from mice underexpressing or overexpressing uncoupling protein 3
Authors: BRAND Martin D. , PAMPLONA Reinald , PORTERO-OTÍN Manuel , REQUENA Jesús R. , ROEBUCK Stephen J. , BUCKINGHAM Julie A. , CLAPHAM John C. , CADENAS Susana
Published: November 2002

Five markers of different kinds of oxidative damage to proteins [glutamic semialdehyde, aminoadipic semialdehyde, N∊-(carboxymethyl)lysine, N∊-(carboxyethyl)lysine and N∊-(malondialdehyde)lysine] and phospholipid fatty acyl composition were identified and measured in skeletal muscle mitochondria isolated from mice genetically engineered to underexpress or overexpress uncoupling protein 3 (UCP3). Mitochondria from UCP3-underexpressing mice had significantly higher levels of oxidative damage than wild-type controls, suggesting that UCP3 functions in vivo as part of the antioxidant defences of the cell, but mitochondria from UCP3-overexpressing mice had unaltered oxidative damage, suggesting that mild uncoupling in vivo beyond the normal basal uncoupling provides little protection against oxidative stress. Mitochondria from UCP3-underexpressing mice showed little change, but mitochondria from UCP3-overexpressing mice showed marked changes in mitochondrial phospholipid fatty acyl composition. These changes were very similar to those previously found to correlate with basal proton conductance in mitochondria from a range of species and treatments, suggesting that high protein expression, or some secondary result of uncoupling, may cause the observed correlation between basal proton conductance and phospholipid fatty acyl composition.
Studies of a Mixed Adsorption Layer of Butan-1-ol and o-Toluidine on Mercury Electrode
Authors: Sieńko Dorota , Gugała Dorota , Nieszporek Jolanta , Jankowska Joanna , Saba Jadwiga
Published: November 2002

The results of thermodynamic analysis of o-toluidine adsorption on a mercury electrode in the presence of various butan-1-ol amounts complete our previous studies on properties of mixed adsorption layers of toluidine isomers-butan-1-ol. The values of the relative surface excess Γ'°T obtained for o-toluidine show that adsorption of this compound decreases with increasing of butan-1-ol concentration. Analysis of adsorption parameters derived from the Frumkin isotherm indicates that in the presence of 0.33 M BuOH in 1 M NaClO4 with adjusted pH 3 as supporting electrolyte, ∆G0 values for o-toluidine are the highest and, at the same time, the strongest repulsive interaction occurs. In the presence of 0.11 M butan-1-ol, smaller values of ∆G0 for o-toluidine correspond to weaker repulsive interaction. Therefore the change of the Γ'°T value for o-toluidine as a function of butan-1-ol concentration is the result of mutual changes of ∆G0 and interaction constant A between adsorbate molecules.
Syntheses and Characterization of Copper(II) and Cobalt(II) Complexes with Tris[2-(benzylamino)ethyl]amine
Authors: Xie Yong-Shu , Jiang Hui , Liu Xue-Ting , Zhou Zhong-Yuan , Liu Qing-Liang , Xu Xiao-Long
Published: November 2002

Two mononuclear complexes [Cu(NCS)(trenb)]ClO4 (1) and [Co(NCS)(trenb)]Cl·H2O (2), where trenb is tris[2-(benzylamino)ethyl]amine, were prepared and characterized by elemental analysis, IR, electronic and EPR spectra. Their crystal structures were determined by X-ray diffraction. Complexes 1 and 2 are both five-coordinated with their metal centers in the distorted trigonal-bipyramidal environment. Each metal(II) ion coordinates with the tetradentate trenb, and one isothiocyanate anion. The two complexes are not isostructural as there are also a chloride and a water molecule in the asymmetric unit of 2. Besides balancing the charge, the chlorides are also involved in intramolecular and intermolecular hydrogen bonds with the secondary amine groups, resulting in a one-dimensional chain structure. UV-VIS spectrum and EPR measurement for 1 have unambiguously confirmed that the five-coordinated structure is retained in solution, even in the donating solvent such as DMF.
Economic costs of post-natal depression in a high-risk British cohort
Authors: Petrou Stavros , Cooper Peter , Murray Lynne , Davidson Leslie L.
Published: November 2002

Background

Post-natal depression is a common condition that can result in distress for the mother and deleterious effects on the development of the infant.

Aims

To estimate the economic costs of post-natal depression in a geographically defined cohort of women at high risk of developing the condition.

Method

Unit costs were applied to estimates of health and social care resource use made by 206 women recruited from antenatal clinics and their infants. Net costs per mother–infant dyad over the first 18 months post-partum were estimated.

Results

Mean mother–infant dyad costs were estimated at £2419.00 for women with post-natal depression and £2026.90 for women without post-natal depression, a mean cost difference of £392.10 (P=0.17). The mean cost differences between women with and without post-natal depression reached statistical significance for community care services (P=0.01), but not for other categories of service. Economic costs were higher for women with extended experiences of the condition.

Conclusions

The results of this study should be used to facilitate the effective planning of services by different agencies.
Molecular cloning, expression and characterization of a novel class glutathione S-transferase from the fungus Cunninghamella elegans
Authors: CHA Chang-Jun , KIM Seong-Jae , KIM Yong-Hak , STINGLEY Robin , CERNIGLIA Carl E.
Published: November 2002

The structural gene for glutathione S-transferase (CeGST1-1) in the fungus Cunninghamella elegans was cloned by screening a cDNA library using a degenerate oligonucleotide probe based on the N-terminal sequence of the purified protein. Open reading frame analysis indicated that the cegst1 gene encodes a protein of 210 amino acid residues. The deduced amino acid sequence showed 25% sequence identity with the sequence of the Pi-class GST from Danio rerio (zebrafish). Similarity was also shown with the Alpha-class GST from Fasciola hepatica (liver fluke; 23% identity), the Mu class from Mus musculus (22%) and the Sigma class from Ommastrephes sloani (squid; 21%). Further screening of a cDNA library with the cegst1 gene probe revealed the presence of another GST isoenzyme (CeGST2-2) in this fungus, which shows 84% sequence identity with CeGST1-1 at the amino acid level. Reverse transcription PCR revealed that cegst2 was also expressed at the mRNA level in the fungus C. elegans. Both cegst genes were overexpressed in Escherichia coli using the expression vector pQE51, displaying specific activities with 1-chloro-2,4-dinitrobenzene of 2.04 and 0.75μmol/min permg of protein respectively. Both enzymes exhibited a similar substrate specificity and inhibition profile, indicating that CeGST1-1 and CeGST2-2 belong to the same GST class. Mutagenesis analysis revealed that Tyr10 in the N-terminal region is essential for catalysis of CeGST1-1. We propose from these results that the CeGSTs are novel Gamma-class GSTs and designated as GSTG1-1 and GSTG2-2 respectively.
DNA family shuffling of hyperthermostable β-glycosidases
Authors: KAPER Thijs , BROUNS Stan J.J. , GEERLING Ans C.M. , VOS Willem M. DE , VAN der OOST John
Published: November 2002

The structural compatibility of two hyperthermostable family 1 glycoside hydrolases, Pyrococcus furiosus CelB and Sulfolobus solfataricus LacS, as well as their kinetic potential were studied by construction of a library of 2048 hybrid β-glycosidases using DNA family shuffling. The hybrids were tested for their thermostability, ability to hydrolyse lactose and sensitivity towards inhibition by glucose. Three screening rounds at 70°C led to the isolation of three high-performance hybrid enzymes (hybrid 11, 18 and 20) that had 1.5—3.5-fold and 3.5—8.6-fold increased lactose hydrolysis rates compared with parental CelB and LacS respectively. The three variants were the result of a single crossover event, which gave rise to hybrids with a LacS N-terminus and a main CelB sequence. Constructed three-dimensional models of the hybrid enzymes revealed that the catalytic (βα)8-barrel was composed of both LacS and CelB elements. In addition, an extra intersubunit hydrogen bond in hybrids 18 and 20 might explain their superior stability over hybrid 11. This study demonstrates that extremely thermostable enzymes with limited homology and different mechanisms of stabilization can be efficiently shuffled to form stable hybrids with improved catalytic features.
Identification of two domains and distal histidine ligands to the four haems in the bacterial c-type cytochrome NapC; the prototype connector between quinol/quinone and periplasmic oxido-reductases
Authors: CARTRON Michaël L. , ROLDÁN M. Dolores , FERGUSON Stuart J. , BERKS Ben C. , RICHARDSON David J.
Published: November 2002

NapC is a tetra-haem member of a family of bacterial membrane-anchored multi-haem c-type cytochromes implicated in electron transfer between membrane quinols and periplasmic enzymes. The water-soluble tetra-haem fragment of Paracoccus pantotrophus NapC has been expressed as a periplasmic protein (NapCsol) in Paracoccus denitrificans, P. pantotrophus and Escherichia coli. Site-specific mutagenesis of NapCsol, combined with spectroscopic studies, suggests that each haem iron centre has bis-histidinyl co-ordination. Four proximal ligands arise from each of four Cys-Xaa-Xaa-Cys-His haem-binding motifs; candidates for the four distal ligands are His81, His99, His174 and His194. NapCH81A, NapCH99A, NapCH174A and NapCH194A mutants (with alanine substituted for each of the four candidate residues) have all been purified from E. coli. In each case, one of the haems has become high-spin, as judged by the presence of a broad absorption band between 620nm and 650nm for the oxidized cytochrome; this feature is absent for wild-type protein and presumably arises because of the absence of the distal histidine ligand from one of the haems. NapCH81A and NapCH174A are less well expressed in E. coli than NapCH99A and NapCH194A and cannot be detected when expressed in P. denitrificans or P. pantotrophus. In vitro and in vivo complementation studies demonstrate that the soluble periplasmic NapC can mediate electron transfer from quinols to the periplasmic nitrate reductase. This capacity was retained in vitro with the NapCH99A and NapCH194A mutants but was lost in vivo. A model for the structural organization of NapCsol into two domains, each containing a di-haem pair, is proposed. In this model, each haem pair obtains one distal haem ligand from its own domain and a second from the other domain. The suggestion of two domains is supported by observations that the 24kDa NapCsol cleaves to yield a 12kDa haem-staining band. Determination of the cleavage site showed it was between two equally sized di-haem domains predicted from sequence analysis.
Active Snf1 protein kinase inhibits expression of the Saccharomyces cerevisiae HXT1 glucose transporter gene
Authors: TOMÁS-COBOS Lidia , SANZ Pascual
Published: November 2002

Expression of HXT1, a gene encoding a Saccharomyces cerevisiae low-affinity glucose transporter, is regulated by glucose availability, being activated in the presence of glucose and inhibited when the levels of the sugar are scarce. In this study we show that Snf1 protein kinase participates actively in the inhibition of HXT1 expression. Activation of Snf1, either by physiological conditions (growth in low-glucose conditions) or by eliminating any of its negative regulators, such as Hxk2 or Reg1, leads to an inhibition of HXT1 expression. We also show that Std1, another known negative regulator of HXT1 expression, interacts physically with active Snf1 protein kinase. Std1 also interacts physically with Rgt1, a transcription factor involved in HXT1 expression, suggesting that the transcriptional properties of Rgt1 could be modulated either directly or indirectly by Std1 and Snf1 protein kinase. Finally, we show that Rgt1 interacts physically with Ssn6, a major transcriptional repressor, to regulate negatively HXT1 expression when glucose is depleted.
The role of myosin in vesicle transport during bovine chromaffin cell secretion
Authors: ÑECO Patricia , GIL Anabel , MAR FRANCÉS María del , VINIEGRA Salvador , GUTIÉRREZ Luis M.
Published: November 2002

Bovine adrenomedullary cells in culture have been used to study the role of myosin in vesicle transport during exocytosis. Amperometric determination of calcium-dependent catecholamine release from individual digitonin-permeabilized cells treated with 3μM wortmannin or 20mM 2,3-butanedione monoxime (BDM) and stimulated by continuous as well as repetitive calcium pulses showed alteration of slow phases of secretion when compared with control untreated cells. The specificity of these drugs for myosin inhibition was further supported by the use of peptide-18, a potent peptide affecting myosin light-chain kinase activity. These results were supported also by studying the impact of these myosin inhibitors on chromaffin granule mobility using direct visualization by dynamic confocal microscopy. Wortmannin and BDM affect drastically vesicle transport throughout the cell cytoplasm, including the region beneath the plasma membrane. Immunocytochemical studies demonstrate the presence of myosin types II and V in the cell periphery. The capability of antibodies to myosin II in abrogating the secretory response from populations of digitonin-permeabilized cells compared with the modest effect caused by anti-myosin V suggests that myosin II plays a fundamental role in the active transport of vesicles occurring in the sub-plasmalemmal area during chromaffin cell secretory activity.
Complex I-mediated reactive oxygen species generation: modulation by cytochrome c and NAD(P)+ oxidation–reduction state
Authors: KUSHNAREVA Yulia , MURPHY Anne N. , ANDREYEV Alexander
Published: November 2002

Several lines of evidence indicate that mitochondrial reactive oxygen species (ROS) generation is the major source of oxidative stress in the cell. It has been shown that ROS production accompanies cytochrome c release in different apoptotic paradigms, but the site(s) of ROS production remain obscure. In the current study, we demonstrate that loss of cytochrome c by mitochondria oxidizing NAD+-linked substrates results in a dramatic increase of ROS production and respiratory inhibition. This increased ROS production can be mimicked by rotenone, a complex I inhibitor, as well as other chemical inhibitors of electron flow that act further downstream in the electron transport chain. The effects of cytochrome c depletion from mitoplasts on ROS production and respiration are reversible upon addition of exogenous cytochrome c. Thus in these models of mitochondrial injury, a primary site of ROS generation in both brain and heart mitochondria is proximal to the rotenone inhibitory site, rather than in complex III. ROS production at complex I is critically dependent upon a highly reduced state of the mitochondrial NAD(P)+ pool and is achieved upon nearly complete inhibition of the respiratory chain. Redox clamp experiments using the acetoacetate/d-β-hydroxybutyrate couple in the presence of a maximally inhibitory rotenone concentration suggest that the site is approx. 50mV more electronegative than the NADH/NAD+ couple. In the absence of inhibitors, this highly reduced state of mitochondria can be induced by reverse electron flow from succinate to NAD+, accounting for profound ROS production in the presence of succinate. These results lead us to propose a model of thermodynamic control of mitochondrial ROS production which suggests that the ROS-generating site of complex I is the Fe—S centre N-1a.
Stigma and expressed emotion: a study of people with schizophrenia and their family members in China
Authors: Phillips Michael R. , Pearson Veronica , Li Feifei , Xu Minjie , Yang Lawrence
Published: November 2002

Background

The most damaging effect of stigma is the internalisation of others' negative valuations.

Aims

To explore the factors that mediate patients' emotional and cognitive responses to stigma.

Method

Based on responses to 10 open-ended questions about stigma appended to the Chinese version of the Camberwell Family Interview, trained coders rated the effect of stigma on both patients and family members in 1491 interviews conducted with 952 family members of 608 patients with schizophrenia at 5 sites around China from 1990 to 2000.

Results

Family members reported that stigma had had a moderate to severe effect on the lives of patients over the previous 3 months in 60% of the interviews, and on the lives of other family members in 26% of the interviews. The effect of stigma on patients and family members was significantly greater if the respondent had a high level of expressed emotion, if the patient had more severe positive symptoms, if the respondent was highly educated and if the family lived in a highly urbanised area.

Conclusions

Clinicians should assess the effect of stigma as part of the standard work-up for patients with mental illness, and help patients and family members reduce the effect of stigma on their lives.
Focus on psychiatry in Italy
Authors: Piccinelli Marco , Politi Pierluigi , Barale Francesco
Published: November 2002

Italy has experienced a significant change in its mental health sector, with a radical shift from old mental institutions to new community-based psychiatric services. The Italian experience attracted international attention and, in some instances, led to similar changes occurring abroad. Recently, economic considerations are imposing additional challenges on the health care system in general, with psychiatry facing distinct and peculiar problems due to its unique organisation and objectives. This paper aims:

(a) to provide a historical overview of the changes in mental health provision in Italy over the past century;

(b) to describe the present organisation of mental health services;

(c) to show the impact of financing on the mental health sector;

(d) to acknowledge the education and training programmes in mental health;

(e) to outline research directions and activities.
Tyrosine phosphorylation and dissociation of occludin–ZO-1 and E-cadherin–β-catenin complexes from the cytoskeleton by oxidative stress
Authors: RAO Radhakrishna K. , BASUROY Shyamali , RAO Vijay U. , KARNAKY Karl J. , GUPTA Akshay
Published: November 2002

The oxidative-stress-induced alteration in paracellular junctional complexes was analysed in Caco-2 cell monolayer. Oxidative stress induced a rapid increase in tyrosine phosphorylation of occludin, zonula occludens (ZO)-1, E-cadherin and β-catenin. An oxidative-stress-induced decrease in transepithelial electrical resistance was associated with a redistribution of occludin—ZO-1 and E-cadherin—β-catenin complexes from the intercellular junctions. Genistein, a tyrosine kinase inhibitor, prevented the oxidative-stress-induced decrease in resistance and redistribution of protein complexes. Occludin, ZO-1, E-cadherin and β-catenin in the Triton-insoluble cytoskeletal fraction were reduced by oxidative stress, which was prevented by genistein. Oxidative stress also reduced the co-immunoprecipitation of ZO-1 with occludin, which was prevented by genistein. Co-immunoprecipitation of β-catenin with E-cadherin was unaffected by oxidative stress or genistein. ZO-1, E-cadherin and β-catenin in the plasma membrane or membrane-cytoskeleton were either slightly reduced or unaffected by oxidative stress or genistein. These results show that oxidative stress induces tyrosine phosphorylation and cellular redistribution of occludin—ZO-1 and E-cadherin—β-catenin complexes by a tyrosine-kinase-dependent mechanism.
Substance P-stimulated interleukin-8 expression in human colonic epithelial cells involves Rho family small GTPases
Authors: ZHAO Dezheng , KUHNT-MOORE Sabina , ZENG Huiyan , PAN Amy , WU Jack S. , SIMEONIDIS Simos , MOYER Mary P. , POTHOULAKIS Charalabos
Published: November 2002

Interaction of the neuropeptide substance P (SP) and its neurokinin-1 receptor (NK-1R) plays an important role in the pathophysiology of intestinal inflammation. SP is known to stimulate production of interleukin (IL)-6 and IL-8 in the U-373-MG human astrocytoma cell line via activation of p38 MAPK (mitogen-activated protein kinase) and nuclear factor (NF)-κB, respectively. However, the signalling mechanisms by which SP-NK-1R interaction induces NF-κB activation and IL-8 expression are still not clear. In this study we demonstrate that SP stimulates IL-8 secretion and IL-8 promoter activity in the NCM460 non-transformed human colonic epithelial cell line transfected with NK-1R cDNA. Our results indicate that inhibition of endogenous Rho family proteins (RhoA, Rac1 and Cdc42) by their respective dominant negative mutants significantly decreases SP-induced IL-8 secretion and IL-8 promoter activity. We also demonstrate that SP rapidly activates RhoA, Rac1 and Cdc42 and that co-expression of the dominant negative mutants of RhoA, Rac1 and Cdc42 in NK-1R cDNA-transfected NCM460 cells significantly inhibits SP-induced NF-κB-dependent gene expression. These results demonstrate that Rho family small GTPases RhoA, Rac1 and Cdc42 are novel signal transducers for SP-stimulated IL-8 expression.
Pd-Catalyzed Cross-Coupling Reaction of Sterically Hindered Vinyl Iodides and Organozinc Reagents. Synthesis of Vitamin D Analogues with an Aromatic Ring Attached at C-17
Authors: Przezdziecka Agnieszka , Kurek-Tyrlik Alicja , Wicha Jerzy
Published: November 2002

Palladium-catalyzed coupling of steroid 17-iodo-6β-methoxy-3α,5-cyclo-5α-androst-16-ene (4) 17-iodoandrosta-5,16-dien-3β-ol (5), and structurally similar (3aS,7R,7aR)-benzenesulfonyl-3-iodo-3a-methyl-3a,4,5,6,7,7a-hexahydro-1H-indene (6) with various arylzinc chlorides, which were generated from aryl bromides 8 [1-bromomethylbenzene (8a), O-(triethylsilyl-2-bromophenyl)propan-2-ol (8b), 2-(4-bromophenyl)propan-2-ol (8c), 4-bromobenzonitrile (8d), 4-bromobenzoic acid methyl ester (8e), 4-bromobenzoic acid tert-butyl ester (8f) and 3-bromopyridine (8g)] via aryllihium derivatives (the Negishi coupling) was examined. The respective cross-coupling products were obtained in good yields for all aryl bromides except of 8c and 8e. Building blocks for synthesis of certain vitamin D analogues have been prepared.
Characterization of iron-binding motifs in Candida albicans high-affinity iron permease CaFtr1p by site-directed mutagenesis
Authors: FANG Hao-Ming , WANG Yue
Published: November 2002

A peptide motif Glu-Xaa-Xaa-Glu has been implicated in direct binding of ferric iron in several proteins involved in iron transport, sensing or storage. However, it is not known whether the motif alone is sufficient for iron binding and whether functional replacement of the conserved residues by other amino acids with similar properties is possible. We previously identified a Candida albicans iron permease, CaFtr1p, which contains five Glu-Xaa-Xaa-Glu motifs [Ramanan and Wang (2000) Science 288, 1062—1065]. In this study, we investigated the role of each of these motifs in iron uptake by site-directed mutagenesis. Substitution of Ala for any one of the two Glu residues in Glu-Gly-Leu-Glu158—161 abolished iron-uptake activity, while the same substitution in any of the other four motifs had little effect, indicating that only the motif at position 158—161 is required for iron transport. We then evaluated the importance of each of the residues within and immediately adjacent to this motif in iron uptake. The permease remained active when any one of the Glu residues was replaced by Asp, while it became inactive when both were replaced. We also found that the amino acid immediately in front of Glu-Gly-Leu-Glu158—161 must be either Arg or Lys. In addition, substitution of any of the two residues in the middle with several structurally distinct amino acids had no detectable effect on iron uptake. Here we propose to extend the iron-binding motif to Arg/Lys-Glu/Asp-Xaa-Xaa-Glu or Arg/Lys-Glu-Xaa-Xaa-Glu/Asp, which may serve as a guide for the identification of potential iron-binding sites in proteins.
Cell population modelling of yeast glycolytic oscillations
Authors: HENSON Michael A. , MÜLLER Dirk , REUSS Matthias
Published: November 2002

We investigated a cell-population modelling technique in which the population is constructed from an ensemble of individual cell models. The average value or the number distribution of any intracellular property captured by the individual cell model can be calculated by simulation of a sufficient number of individual cells. The proposed method is applied to a simple model of yeast glycolytic oscillations where synchronization of the cell population is mediated by the action of an excreted metabolite. We show that smooth one-dimensional distributions can be obtained with ensembles comprising 1000 individual cells. Random variations in the state and/or structure of individual cells are shown to produce complex dynamic behaviours which cannot be adequately captured by small ensembles.
In vitro aggregation of the regulated secretory protein chromogranin A
Authors: JAIN Renu K. , CHANG Wen Tzu , GEETHA Chitta , JOYCE Paul B.M. , GORR Sven-Ulrik
Published: November 2002

Aggregation chaperones, consisting of secretory proteins that contain a hexa-histidine epitope tag, enhance the calcium-induced aggregation of regulated secretory proteins and their sorting to secretory granules. The goal of this study was to gain a better understanding of this unusual aggregation mechanism. Hexa-histidine-epitope-tagged secreted alkaline phosphatase, an aggregation chaperone, enhanced the in vitro aggregation of chromogranin A in the presence of calcium, but not in the presence of magnesium or other divalent cations. As an exception, chromogranin was completely aggregated by zinc, even in the absence of the aggregation chaperone. In addition, fluorescence spectroscopy of the aggregation reaction mixture showed an increase in fluorescence intensity consistent with the formation of protein aggregates. The calcium-induced aggregation of chromogranin A was completely inhibited by 0.2% Triton X-100, suggesting that it involves hydrophobic interactions. In contrast, the detergent did not affect chaperone-enhanced aggregation, suggesting that this aggregation does not depend on hydrophobic interactions. EDTA-treated chaperone did not enhance chromogranin A aggregation, indicating that divalent cations are necessary for chaperone action. Although the structure of the aggregation chaperone was not important, the size of the chaperone was. Thus the free His-hexapeptide could not substitute for the aggregation chaperone. Based on these results, we propose that the hexa-histidine tag, in the context of a polypeptide, acts as a divalent cation-dependent nucleation site for chromogranin A aggregation.
Synthesis of Tricarbonyl(diacetylarene)chromium and Tricarbonyl(diformylarene)chromium Complexes
Authors: Kmentová Iveta , Toma Štefan
Published: November 2002

Tricarbonylchromium complexes of diacetylbenzenes and 2,2'-diacetylbiphenyl were prepared in reasonable yields by direct complexation of the starting materials. Tricarbonylchromium complexes of diformylbenzenes and 2,2'-diformylbiphenyl were prepared in good yields by the complexation of the corresponding dioxolanes followed by acidic hydrolysis of the protective groups.
Long-term hospital attendance of children and adults who have undergone removal of normal or inflamed appendices
Authors: Dummett Nicola J. , Maughan Nicola J. , Worrall-Davies Anne
Published: November 2002

Background

Early studies suggested that presentations with unexplained acute abdominal pain were associated with increased long-term rates of hospital attendance and self-harm, especially in women, but few studies were large enough for definitive findings.

Aims

To test the hypothesis that such presentations are followed by higher long-term utilisation rates of secondary health care even excluding further abdominal symptoms, and particularly for self-harm, than presentations with acute appendicitis.

Method

New hospital attendance rates, liaison psychiatry attendances and self-harm attendances of patients with normal appendices at emergency appendicectomy were compared with those of appendicitis patients.

Results

Attendance rates of all kinds were significantly higher for normal appendix patients than for appendicitis patients, with equal strengths of finding for males and females.

Conclusions

People with normal appendices at emergency appendicectomy show higher long-term rates of hospital attendance. This has implications for how these patients are best managed by health care systems.
Geographical variations in substance misuse services waiting
times and methadone treatment of opiate dependence in England and
Wales
Authors: Luty Jason
Published: November 2002

AIMS AND METHODS

A postal and telephone survey of 140 community drug teams was undertaken
to determine geographical variations in waiting times and methadone
prescribing policies.

Results

The average waiting time was 7.2 weeks for assessment and 10.6 weeks from
referral to receiving methadone. ‘Methadone maintenance’ was not
available in 25 units, although it was commonly provided in 41 units.
In-patient detoxification for illicit drug dependence was available in
108 units, of which 59 units had access to beds in dedicated
drug-dependency units, while the remaining 49 units referred in-patients
to general psychiatry wards.

Clinical Implications

Despite government guidelines, it was clear that methadone was readily
available to opiate users in some units whereas prescribing was very
limited in others. The great variation in prescribing policies and
waiting lists between community drug teams will make it extremely
difficult to compare their effectiveness. Waiting lists are an explicit
target for the National Treatment Agency involved in commissioning
substance misuse services.
Dual role for mitogen-activated protein kinase (Erk) in insulin-dependent regulation of Fra-1 (fos-related antigen-1) transcription and phosphorylation
Authors: HURD Toby W. , CULBERT Ainsley A. , WEBSTER Kenneth J. , TAVARÉ Jeremy M.
Published: November 2002

Insulin regulates the activity of the AP-1 (activator protein-1) transcriptional complex in several cell types. One component of the AP-1 complex is the transcription factor Fra-1 (fos-related antigen-1), and we have demonstrated previously that insulin stimulates the expression of Fra-1 mRNA in CHO.T cells [Griffiths, Black, Culbert, Dickens, Shaw, Gillespie and Tavaré (1998) Biochem. J. 335, 19—26]. Here we demonstrate that insulin stimulates the activity of a fra-1 promoter linked to a luciferase reporter gene, indicating that the ability of insulin to induce expression of Fra-1 mRNA is due, at least in part, to an increase in gene transcription. Furthermore, we found that insulin induces the serine phosphorylation of Fra-1 and reduces its mobility during SDS/PAGE as a result of phosphorylation. The ability of insulin to induce the accumulation of Fra-1 mRNA, stimulate the fra-1 promoter and stimulate phosphorylation of Fra-1 all require the mitogen-activated protein (MAP) kinase cascade, which leads to the activation of extracellular-signal-regulated kinase (Erk) 1/2. Consequently, our results demonstrate that the Erk cascade plays a dual role in the co-ordinated regulation of the transcription and the phosphorylation of Fra-1 by insulin.