bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analyses of Climate Variability and Trends in the Oil Palm Belt of Ghana
Authors: Zutah Victor Tetteh , Sarkodie-Addo Joseph , Tuffour Henry Oppong , Tandoh Paul Kweku 
Published: February 2024

The current production of oil palm in Africa has been severely limited by long periods of drought and perennial floods due to the increased rates of climate change. The study was aimed at assessing the climatic variability trends in 7 major Oil Palm growing areas (Benso, Mpohor, Bogoso, Twifo Praso, Kade, Juabeng and Brewaniese) located in the oil palm belt in Ghana spanning the semideciduous and the wet evergreen rainforest zones of Ghana using 30 years of historical weather data (1993-2022). The data was analysed to evaluate the extent of seasonal changes in weather over the 30-year period using the Statistical Package for Social Sciences (SPSS 20.0 version), using descriptive statistics and time series analysis. Trend analysis was conducted using the non-parametric Mann-Kendall (MK) and Sen’s slope estimator tests. A seasonal trend in rainfall was observed at all sites with maximum levels observed between May and July as well as a minor rainy season in September to Mid-November. The Mann-Kendall trend analysis showed a generally increasing trend at most stations in rainfall, temperature and solar radiation. A generally increasing trend in annual rainfall was observed from 1993-2022 with significant trends at Mpohor and Juabeng. The trend was higher in the moist evergreen rainforest zone than in the semi-deciduous rainforest zone. An average increase of 6.7 mm/yr in rainfall trend was observed for the period. An increasing trend in monthly maximum, minimum and mean temperatures were also observed. Significant increases in mean temperatures were observed at Bogoso (0.022°C/yr), Benso (0.018°C/yr), Juabeng (0.011°C/yr) and Mpohor (0.017°C/yr). The trend in mean annual solar radiation was generally not significant except in Benso where the mean solar radiation increased at the rate of 0.044 MJ/day. Higher drought levels in the first half year combined with very heavy rains later in the year are features of the ongoing climate change menace.
Structural double-mutant cycle analysis of a hydrogen bond network in ketosteroid isomerase from Pseudomonas putida biotype B
Authors: JANG Do Soo , CHA Hyung Jin , CHA Sun-Shin , HONG Bee Hak , HA Nam-Chul , LEE Ja Young , OH Byung-Ha , LEE Heung-Soo , CHOI Kwan Yong 
Published: September 2004

KSI (ketosteroid isomerase) catalyses an allylic isomerization reaction at a diffusion-controlled rate. A hydrogen bond network, Asp99···Water504···Tyr14···Tyr55···Tyr30, connects two critical catalytic residues, Tyr14 and Asp99, with Tyr30, Tyr55 and a water molecule in the highly apolar active site of the Pseudomonas putida KSI. In order to characterize the interactions among these amino acids in the hydrogen bond network of KSI, double-mutant cycle analysis was performed, and the crystal structure of each mutant protein within the cycle was determined respectively to interpret the coupling energy. The ΔΔGo values of Y14F/D99L (Tyr14→Phe/Asp99→Leu) KSI, 25.5 kJ/mol for catalysis and 28.9 kJ/mol for stability, were smaller than the sums (i.e. 29.7 kJ/mol for catalysis and 34.3 kJ/mol for stability) for single mutant KSIs respectively, indicating that the effect of the Y14F/D99L mutation was partially additive for both catalysis and stability. The partially additive effect of the Y14F/D99L mutation suggests that Tyr14 and Asp99 should interact positively for the stabilization of the transition state during the catalysis. The crystal structure of Y14F/D99L KSI indicated that the Y14F/D99L mutation increased the hydrophobic interaction while disrupting the hydrogen bond network. The ΔΔGo values of both Y30F/D99L and Y55F/D99L KSIs for the catalysis and stability were larger than the sum of single mutants, suggesting that either Tyr30 and Asp99 or Tyr55 and Asp99 should interact negatively for the catalysis and stability. These synergistic effects of both Y30F/D99L and Y55F/D99L mutations resulted from the disruption of the hydrogen bond network. The synergistic effect of the Y55F/D99L mutation was larger than that of the Y30F/D99L mutation, since the former mutation impaired the proper positioning of a critical catalytic residue, Tyr14, involved in the catalysis of KSI. The present study can provide insight into interpreting the coupling energy measured by double-mutant cycle analysis based on the crystal structures of the wild-type and mutant proteins.
Characterization and functional analysis of the 5′-flanking region of the mouse 20α-hydroxysteroid dehydrogenase gene
Authors: HIRABAYASHI Keiji , ISHIDA Maho , SUZUKI Masatoshi , YAMANOUCHI Keitaro , NISHIHARA Masugi 
Published: September 2004

20α-Hydroxysteroid dehydrogenase (20α-HSD), which metabolizes progesterone to an inactive steroid in the corpus luteum of mice and rats but not of humans, is thought to play a crucial role in shortening the oestrous cycles in these rodent species. We determined the nucleotide sequence of the 5′-flanking region of the mouse 20α-HSD gene, and examined its promoter activity using a rat luteinized granulosa cell culture. A reporter assay, using reporter constructs of various lengths of the 5′-flanking region, revealed that the region between −83 and 60 bp upstream of the transcription start site was essential for transcriptional activity. Furthermore, mutational analysis demonstrated that a putative Sp1 site in this region was critical to the expression of the reporter gene. Electrophoretic mobility-shift assays showed that the interaction of proteins in a nuclear extract from rat luteinized granulosa cells with this region was inhibited by a competitor having the wild-type Sp1 sequence in its promoter, but not a mutated Sp1 sequence. Supershift analysis confirmed that Sp1 and Sp3 were present in the nuclear extract of these cells, and that these factors bound to the element. Finally, promoter activity was elevated by the co-transfection of an Sp1 expression vector, and, to a lesser extent, by an Sp3 expression vector, supporting further the involvement of these factors in the expression of the 20α-HSD gene.
Myristoylated alanine-rich C kinase substrate (MARCKS) is involved in myoblast fusion through its regulation by protein kinase Cα and calpain proteolytic cleavage
Authors: DULONG Sandrine , GOUDENEGE Sebastien , VUILLIER-DEVILLERS Karine , MANENTI Stéphane , POUSSARD Sylvie , COTTIN Patrick 
Published: September 2004

MARCKS (myristoylated alanine-rich C kinase substrate) is a major cytoskeletal protein substrate of PKC (protein kinase C) whose cellular functions are still unclear. However numerous studies have implicated MARCKS in the stabilization of cytoskeletal structures during cell differentiation. The present study was performed to investigate the potential role of Ca2+-dependent proteinases (calpains) during myogenesis via proteolysis of MARCKS. It was first demonstrated that MARCKS is a calpain substrate in vitro. Then, the subcellular expression of MARCKS was examined during the myogenesis process. Under such conditions, there was a significant decrease in MARCKS expression associated with the appearance of a 55 kDa proteolytic fragment at the time of intense fusion. The addition of calpastatin peptide, a specific calpain inhibitor, induced a significant decrease in the appearance of this fragment. Interestingly, MARCKS proteolysis was dependent of its phosphorylation by the conventional PKCα. Finally, ectopic expression of MARCKS significantly decreased the myoblast fusion process, while reduced expression of the protein with antisense oligonucleotides increased the fusion. Altogether, these data demonstrate that MARCKS proteolysis is necessary for the fusion of myoblasts and that cleavage of the protein by calpains is involved in this regulation.
Cytochrome c oxidase subunit IV as a marker of protein kinase Cε function in neonatal cardiac myocytes: implications for cytochrome c oxidase activity
Authors: OGBI Mourad , CHEW Catherine S. , POHL Jan , STUCHLIK Olga , OGBI Safia , JOHNSON John A. 
Published: September 2004

We have previously demonstrated that low concentrations of phorbol esters stimulate the selective translocation of protein kinase C (PKC) α and ε from the cell soluble to the particulate fraction in NCMs (neonatal rat cardiac myocytes). We therefore determined if the in vitro phosphorylation of substrates in these fractions could be used as assays of PKCα or ε activation. Intact cell phorbol ester treatment caused a decline in the in vitro32P-incorporation into several proteins in the cell-soluble fraction. These declines occurred in the presence or absence of in vitro Ca2+ and probably reflected the exit of PKC isoenzymes from the soluble fraction. In contrast, an approx. 18 kDa protein incorporated 32P in particulate fractions isolated from 4β-PMA-treated cells in a Ca2+-independent manner. Proteomic and immunoprecipitation analyses indicated that the protein is subunit IV of the cytochrome c oxidase complex (COIV). In vitro phosphorylation of COIV was attenuated by PKC pseudosubstrate peptides. Introduction of an PKCε-selective translocation inhibitor [Johnson, Gray, Chen and Mochly-Rosen (1996) J. Biol. Chem. 271, 24962–24966] into NCMs before 4β-PMA treatments also attenuated the in vitro phosphorylation of COIV. In mitochondrial extracts from 4β-PMA-treated NCMs, the PKCε isoenzyme coimmunoprecipitated with COIV, and cytochrome c oxidase activity was enhanced 2-fold. The in vitro phosphorylation of COIV reflects a novel approach for monitoring PKCε function in NCMs. Furthermore, PKCε probably interacts with COIV in NCM mitochondria to enhance electron-transport chain complex IV activity.
Membrane-bound carboxypeptidase E facilitates the entry of eosinophil cationic protein into neuroendocrine cells
Authors: WU Chia-Mao , CHANG Hao-Teng , CHANG Margaret Dah-Tsyr 
Published: September 2004

ECP (eosinophil cationic protein) is a major component of eosinophil granule proteins, and is used as a clinical biomarker for asthma and allergic inflammatory disease. ECP has been implicated in damage to the cell membrane of many tissue types, but the mechanism is not well known. In the present study, mECP–eGFP–6H, a recombinant fusion protein containing mature ECP (mECP), enhanced green fluorescence protein (eGFP) and a His6 tag (6H), has been expressed, purified and added to GH3 neuroendocrine cells to study the internalization ability of ECP. We found that mECP–eGFP–6H entered into GH3 neuroendocrine cells and inhibited the growth of the cells with an IC50 of 0.8 μM. By yeast two-hybrid screening and immunoprecipitation, we have identified a specific protein–protein interaction between mECP and CPE (carboxypeptidase E), a well characterized metalloprotease. Further in vivo yeast two-hybrid screening has also revealed that residues 318–387 located in a region of unknown function in mature CPE are indispensable for association with mECP. In addition, the uptake of mECP–eGFP–6H is suppressed by dominant-negative expression of the recycling defect mutant pre-pro-HA–CPES471A,E472A in GH3 cells, suggesting that the entry of mECP–eGFP–6H is associated with the recycling of CPE in GH3 cells. Taken together, we have demonstrated that CPE possesses a novel function to facilitate the entry of ECP to neuroendocrine cells, and such an endocytotic process allows the cytotoxic ECP to inhibit growth of the target cells.
Localization of Nox2 N-terminus using polyclonal antipeptide antibodies
Authors: PACLET Marie-Hélène , HENDERSON Lydia M. , CAMPION Yannick , MOREL Françoise , DAGHER Marie-Claire 
Published: September 2004

Nox2/gp91phox (where phox is phagocyte oxidase) is the catalytic membrane subunit of the granulocyte NADPH oxidase complex involved in host defence. The current model of membrane topology of Nox2 is based upon the identification of glycosylation sites, of regions that interact with the regulatory cytosolic factors and of the epitopes recognized by antibodies. So far, the localization of the N-terminus of Nox2 was only speculative. In order to clarify this localization, we raised a polyclonal antiserum against the N-terminal sequence M1GNWVAVNEGL11. Purified antibodies recognize the mature protein as a broad band at 91 kDa (glycosylated form) or a band at 55 kDa after deglycosylation. Immunocytochemistry and flow-cytometry analysis show a strong binding of the anti-N-terminal antibodies to differentiated HL60 cells and neutrophils respectively, after permeabilization only. The N-terminus of Nox2 is therefore present in the mature protein and is located to the cytoplasmic side of the plasma membrane.
Slow-binding inhibitors of prolyl oligopeptidase with different functional groups at the P1 site
Authors: VENÄLÄINEN Jarkko I. , JUVONEN Risto O. , GARCIA-HORSMAN J. Arturo , WALLÉN Erik A. A. , CHRISTIAANS Johannes A. M. , JARHO Elina M. , GYNTHER Jukka , MÄNNISTÖ Pekka T. 
Published: September 2004

POP (prolyl oligopeptidase) specifically hydrolyses a number of small proline-containing peptides at the carboxy end of the proline residue and POP inhibitors have been shown to have cognition-enhancing properties. It has been noted that certain functional groups at the P1 site of the inhibitor, which correspond to the substrate residue on the N-terminal side of the bond to be cleaved, increase the inhibitory potency. However, detailed mechanistic and kinetic analysis of the inhibition has not been studied. In the present study, we examined the effect of different functional groups at the P1 site of the parent inhibitor isophthalic acid bis-(L-prolylpyrrolidine) amide on the binding kinetics to POP. Addition of CHO, CN or COCH2OH groups to the P1 site increased the inhibitory potency by two orders of magnitude (Ki=11.8–0.1 nM) and caused a clear slow-binding inhibition. The inhibitor containing a CHO group had the lowest association rate constant, kon=(2.43±0.12)×105 M−1·s−1, whereas the inhibitor with a CN group exhibited the fastest binding, kon=(12.0±0.08)×105 M−1·s−1. In addition, the dissociation rate was found to be crucially dependent on the type of the functional group. Compounds with COCH2OH and CHO groups had much longer half-lives of dissociation (over 5 h) compared with the compound with the CN group (25 min), although the Ki values of the compounds were relatively similar. A possibility to optimize the duration of inhibition by changing the functional group at the P1 site is important when planning therapeutically useful POP inhibitors.
Thrombangiitis obliterans: Eine Übersicht
Authors: Hoeft Daniela , Kroger Knut , Grabbe Stephan , Dissemond Joachim 
Published: September 2004

ZusammenfassungDie Thrombangiitis obliterans (TAO) ist eine Erkrankung, die durch eine segmentale, nicht‐arteriosklerotische Entzündung der kleinen und mittleren Arterien und Venen charakterisiert ist. Die pathologischen vaskulären Veränderungen finden sich zumeist im Bereich der distalen Extremitäten, selten sind auch die Gefäße viszeraler Organe beteiligt. Betroffen sind vor allem junge männliche Raucher, bei denen es infolge einer Gefäßischämie zur Ausbildung von Ulzerationen und Gangrän der Zehen und Finger kommen kann. Die Diagnose wird aufgrund typischer klinischer Kriterien gestellt, sowie anhand von pathologischen Veränderungen, die sich angiographisch und histologisch nachweisen lassen. Die exakte Ätiologie der TAO ist bis heute unklar, es besteht jedoch eine nachgewiesene Assoziation mit Tabakkonsum. In der aktuellen Literatur wird auch eine autoimmunologische Genese diskutiert, wobei das initiierende Antigen bislang nicht identifiziert werden konnte.Grundlage der Therapie der TAO ist der vollständige Verzicht auf jede Form des Tabakkonsums. Auf der Basis dieses Verzichtes kann eine medikamentöse Therapie, beispielsweise mit repetitiver Gabe von Prostacyclin‐Analoga eingeleitet werden. Die Lebenserwartung der Patienten mit TAO ist unverändert gegenüber der Normalbevölkerung, allerdings besteht bei einer Vielzahl der Patienten die Gefahr der Exulzeration mit nachfolgender Amputation.
15 % Azelainsäuregel in der Behandlung der Akne. Zwei doppelblinde klinische Vergleichsstudien
Authors: Gollnick Harald P. M. , Graupe Klaus , Zaumseil Rolf‐Peter 
Published: September 2004

Zusammenfassung Hintergrund: Die topische Behandlung ist die Therapie erster Wahl für die milde bis mittelschwer ausgeprägte Acne vulgaris. Azelainsäure ist als 20%ige Cremeformulierung seit 15 Jahren als ein wirksames und sicheres Externum etabliert. Eine neue, nicht‐alkoholische Hydrogelformulierung mit 15 % Azelainsäure wurde klinisch gegenüber den Standardexterna 5 % Benzoylperoxid (BPO) und 1 % Clindamycin getestet. Patienten und Methodik: In zwei unabhängigen, multizentrischen, randomisierten Vergleichsstudien bei 351 und 229 Patienten mit papulopustulöser Acne vulgaris wurde das 15 % Azleainsäuregel mit 5 % BPO‐ und 1 % Clindamycingel verglichen. Die Medikamente wurden zweimal täglich über 4 Monate angewendet. Ergebnisse: Das Azelainsäuregel erwies sich dabei mit 70 bzw. 71 % prozentualer Reduktion der entzündlichen Effloreszenzen (Papeln und Pusteln) als genauso wirksam wie BPO und Clindamycin. Das Azelainsäuregel wurde gut vertragen; die Nebenwirkungen (lokales Brennen und Irritationszeichen) traten deutlich weniger als bei BPO, aber häufiger als bei Clindamycin auf. Trotz der Nebenwirkungen wurde das Azelainsäuregel von der überwiegenden Mehrheit der Patienten gut akzeptiert. Schlußfolgerungen: Das Azelainsäuregel stellt eine wirksame topische Monotherapie der milden bis mittelschweren Acne vulgaris dar und ist in der neuen galenischen Formulierung eine Bereicherung in der Therapie der Akne.
The Effect of a Radome on Submillimeter Site-Testing Measurements
Authors: G. Calisse Paolo 
Published: September 2004

AbstractWe evaluate the effect that radome transparency has on atmospheric opacity measurements performed by the skydip technique. We show that, except at rather high opacities, it is not sufficient to ignore losses in the radome (or ‘window’) during the data analysis and then subtract them from the derived atmospheric opacity. Perhaps surprisingly, unless radome transparency is correctly modelled, the atmosphere will appear to have a minimum opacity that is many times greater that the radome losses. Our conclusion is that some previous site studies may have significantly underestimated the quality of the best submilli-metre sites, and that the difference between these sites and poorer sites may be much greater than currently believed. We also show that part of the residual 857-GHz opacity at the best sites, currently ascribed to ‘dry-air opacity’, can in fact be just an artefact caused by not properly modelling the radome during the data analysis.
An Historical Light Curve of CF Octantis from Digitised Images of the Bamberg Plate Archive
Authors: Innis J. L. , Heil P. , Thompson K. , Coates D. W. 
Published: September 2004

AbstractDigital images were made of Bamberg Observatory Sky Patrol plates of the field surrounding the active-chromosphere star CF Octantis (HD 196818). These images, taken with an inexpensive camera, were analysed using standard aperture photometry techniques. Good agreement was found with catalogued photographic magnitudes for stars in the range mpg ∼8.5 to ∼10.5. The root-mean-square deviations in the measured differences for non-variable field stars was found to be of order 0.10 mag, although a small number of larger differences occurred. For CF Oct, a period search of data from 1966 recovered the known 20 d variation due to starspot rotational modulation, with a range of variation of order 0.5 mag photographic. For active-chromosphere stars with moderately large photometric variations (>∼0.3 mag), and moderate to long rotation periods (>∼1 week), careful analysis of similarly obtained digital copies of archive plates may provide valuable insights into historical actvity.
The HI Content of Compact Groups of Galaxies
Authors: Stevens J. B. , Webster R. L. , Barnes D. G. , Pisano D. J. , Drinkwater M. J. 
Published: September 2004

AbstractThe HI content of Hickson Compact Groups in the southern hemisphere is measured using data from the HI Parkes All-Sky Survey (HIPASS), and dedicated observations using the narrow band filter on the Multibeam instrument on the Parkes telescope. The expected HI mass of these groups was estimated using the luminosity, diameter, and morphological types of the member galaxies, calibrated from published data. Taking careful account of non-detection limits, the results show that the compact group population that has been detected by these observations has an HI content similar to that of galaxies in the reference field sample. The upper limits for the undetected groups lie within the normal range; improvement of these limits will require a large increase in sensitivity.
Comprehensive Analysis of RGU Photometry in the Direction to M5
Authors: Karaali S. , Bilir S. , Buser R. 
Published: September 2004

AbstractThe RGU-photographic investigation of an intermediate latitude field in the direction to the Galactic centre is presented. 164 extra-galactic objects, identified by comparison of Minnesota and Basel charts, are excluded from the program. Also, a region with size 0.104 square-degrees, contaminated by cluster (M5) stars and affected by background light of the bright star HD 136202 is omitted. Contrary to previous investigations, a reddening of E(B – V) = 0.046, corresponding to E(G – R) = 0.07 mag is adopted. The separation of dwarfs and evolved stars is carried out by an empirical method, already applied in some of our works. A new calibration for the metallicity determination is used for dwarfs, while the absolute magnitude determination for stars of all categories is performed using the procedures given in the literature. There is good agreement between the observed logarithmic space density histograms and the galactic model gradients. Also, the local luminosity function agrees with Gliese's (1969) and Hipparcos (Jahreiss & Wielen 1997) luminosity functions, for stars with 2 < M(G) ≤ 8 mag. For giants, we obtained two different local space densities from comparison with two Galactic models, i.e. D*(0) = 6.63, close to that of Gliese (1969), and D*(0) = 6.79. A metallicity gradient, d[Fe/H]/dz = –0.20 dex kpc–1, is detected for dwarfs (only) with absolute magnitudes 4 < M(G) ≤ 6, corresponding to a spectral type interval F5–K0.
psrchive and psrfits: An Open Approach to Radio Pulsar Data Storage and Analysis
Authors: Hotan A. W. , van Straten W. , Manchester R. N. 
Published: September 2004

AbstractA new set of software applications and libraries for use in the archival and analysis of pulsar astronomical data is introduced. Known collectively as the psrchive scheme, the code was developed in parallel with a new data storage format called psrfits, which is based on the Flexible Image Transport System (FITS). Both of these projects utilise a modular, object-oriented design philosophy. psrchive is an open source development environment that incorporates an extensive range of c++ object classes and pre-built command line and graphical utilities. These deal transparently and simultaneously with multiple data storage formats, thereby enhancing data portability and facilitating the adoption of the psrfits file format. Here, data are stored in a series of modular header–data units that provide flexibility and scope for future expansion. As it is based on FITS, various standard libraries and applications may be used for data input, output, and visualisation. Both psrchive and psrfits are made publicly available to the academic community in the hope that this will promote their widespread use and acceptance.