bluuebunny/crossref_metadata_2025 huggingface dataset:
PROXIMATE EXPLANATIONS FOR FAILED PACK FORMATION IN LYCAON PICTUS
Authors: McCreery E. Kim , Robbins Robert
Published: July 2002

Among the most social of all canids, the endangered African wild dog lives in packs in which the alpha pair typically monopolizes breeding while nonreproductive members help care for the offspring. Consequently, the size of the breeding population is directly related to the number of packs in the population. Although the formation of new packs affects both individual fitness and population dynamics, little is known about the process of pack formation and the proximate factors that influence the outcome. In this paper, seven cases of attempted pack formation are documented, of which four failed. Three possible explanations for pack annulment are considered: group size, mate competition, and mate choice (i.e. group compatibility). Our observations suggest that group compatibility can influence whether stable reproductive units form. The influence of individual behavior, via the process of pack formation, on population dynamics is discussed. The potential conservation application of the theoretical study of wild dog pack formation is highlighted.
Prevalence of plant parasitic nematodes associated with rice in Ghana with a discussion of their importance
Authors: Coyne Daniel L. , Plowright Richard A. , Twumasi Joe , Hunt David J.
Published: July 2002

A survey of plant parasitic nematodes of rice was made in Ghana between
1994-1997. Fifty-one species in 29 genera were found in 145 fields from
upland, hydromorphic, rainfed lowland and irrigated lowland ecosystems in
the savannah and forest agroecological zones. Eighteen species were
endoparasites of roots. In upland/hydromorphic rice fields in the savannah
zone Pratylenchus spp. (80% of fields) and an undescribed species of
Ditylenchus (78%) were most prevalent, whilst Coslenchus franklinae (84%)
and Helicotylenchus spp. (76%) were most prevalent in the forest zone
fields. Maximum population densities encountered were 960 C. franklinae per
100 ml soil and 700 Ditylenchus n. sp. per g root. In the savannah zone
Hirschmanniella spp. (100%) were more prevalent than other nematodes in
lowland rice, but in the forest zone Xiphinema bergeri (71%) was the most
prevalent nematode in lowland rice. Occurrence of nematode species was
different in different agroecological zones and rice ecosystems. There was
no relationship between rice plant height and nematode population densities
in crops close to harvest time in upland/hydromorphic fields in the savannah
zone. Predominance des nematodes phytoparasites sur le riz au Ghana et
discussion sur leur importance - Une prospection concernant les nematodes
associes au riz a ete effectuee au Ghana de 1994 a 1997. Cinquante-et-une
especes appartenant a 29 genres ont ete trouvees dans 145 rizieres de
plateau, de bas-fonds, pluviales ou irriguees, tant en savane que dans des
zones agroecologiques forestieres. Dix-huit especes sont des endoparasites
racinaires. Dans les rizieres de plateau ou de bas-fonds en zone de savane
Pratylenchus spp. (80% des rizieres) et une espece non encore decrite de
Ditylenchus (78%) sont les plus abondants, tandis que Coslenchus franklinae
(84%) et Helicotylenchus spp. (78%) le sont dans les rizieres de zone
forestiere. Les densites maximales de population observees concernent C.
franklinae (960 per 100 cm3 de sol) et Ditylenchus n. sp. (700 per 1 g de
racines). Hirschmanniella spp. etaient plus abondants (100 %) que les autres
nematodes dans les rizieres de bas-fonds de savane, tandis c'etait Xiphinema
bergeri (71%) dans ce meme type de rizieres en zones forestieres. La
presence des differentes especes de nematodes varie suivant la zone
agroecologique et l'ecosysteme de la riziere. Il n'y a pas de relation entre
la hauteur des plants de riz et la densite des populations de nematodes pour
des cultures proches de la recolte dans les rizieres de plateau ou de
bas-fonds situees en savane.
Observations on three species of the subfamily Acrobelinae (Nematoda: Cephalobidae) from India
Authors: Tahseen Qudsia , Ahmad Irfan , Jairajpuri M. Shamim
Published: July 2002

Three populations belonging to Zeldia punctata , Chiloplacus subtenuis and
Seleborca complexa , respectively, were studied morphometrically, with
additional details provided by scanning electron microscopy. Z. punctata ,
Aligarh population, is characterised by a medium sized body with five
non-crenate lateral incisures, prominently cuticularized cheilostom, dentate
guard processes of primary cephalic axils reaching about 66% of cephalic
probolae length. C. subtenuis, population collected from Surat, India, shows
five lateral incisures, labial probolae bifurcate about 20% of length, with
short and blunt margins, female tail long with 22-24 annules, without
indented tip, males with four precloacal and four post-cloacal pairs genital
papillae and with inner lateral incisures interrupted at tail. The Aligarh
population of S. complexa shows double, coarsely striated cuticle, two
areolated lateral incisures, labial probolae bifurcate to about 67% of
length, each arm bearing seven to nine tines on the outer side, middle tine
on cephalic probolae at secondary cephalic axils enlarged, males with
strongly developed, cephalated spicules and with three paired and a single
median pre-cloacal and five post-cloacal pairs of genital papillae.
Observations sur trois especes de la sous-familledes Acrobelinae (Nematoda:
Cephalobidae) de l'Inde- Trois populations appartenant chacune a Zeldia
punctata , Chiloplacus tenuis et Seleborca complexa ont ete etudiees, des
donnees complementaires en microscopie electronique a balayage etant
fournies. Z. punctata , population Aligarh, est caracterise par un corps de
taille moyenne avec cinq incisures laterales non crenelees, un cheilostome
cuticularise proeminent, des proces de protection des axilles cephaliques
primaires atteignant environ 66% de la longueur des proboles cephaliques. La
population de C. subtenuis, collectee a Surat, Inde, montre cinq incisures
laterales, des proboles labiales bifurquees a 20% de leur longueur et a
sommets courts et lisses, la queue de la femelle comportant 22 a 24 anneaux
et a extremite non indentee, les males avec quatre paires precloacales et
quatre paires postcloacales de papilles genitales, les incisures laterales
internes etant interrompues sur la queue. La population de S. complexa
provenant d'Aligarh possede une cuticule double a annelation forte, deux
incisures laterales areolees, des proboles labiales bifurquees a environ 67%
de leur longueur, chaque branche portant sept a neuf pointes sur la marge
exterieure, la pointe mediane elargie des proboles cephaliques au niveau des
axilles cephaliques secondaires, les males a spicules fortement developpes
et renfles a l'extremite anterieure, les papilles genitales etant reparties
en trois paires pre-cloacales, une mediane unique pre-cloacale et cinq
paires post-cloacales.
Siderite zonation within the Brent Group: microbial influence or aquifer flow?
Authors: Wilkinson M. , Haszeldine R. S. , Fallick A. E. , Osborne M. J.
Published: July 2002

A three-fold zonation can be imaged within authigenic siderite from sandstones of the Brent Group using back-scatter SEM techniques. We interpret this zonation in terms of the biogeochemical zonation of shallow buried sediment. The innermost siderite crystal zone is very Fe rich (95.0±0.5 mol.% FeCO3), with high Mn levels relative to Ca and Mg. This is interpreted as forming within the Fe reduction zone, with Mn from the closely associated Mn reduction zone. The second siderite crystal zone is frequently represented either by an episode of dissolution, or is impure (80±1 mol.% FeCO3), and this corresponds to the sulphate reduction zone. The outer crystal zone is intermediate in composition, and is equated with the zone of methanogenesis (88±1 mol.% FeCO3). Isotopic values cannot be assigned to individual crystal zones. Bulk δ18O values (−2.7 to −13.0‰ V-PDB) are not consistent with precipitation from seawater at low temperatures, but suggest meteoric pore-waters. δ13C data (−4.3 to −15.7‰ V-PDB) are consistent with microbially-mediated precipitation.

Pyrite and siderite are usually mutually exclusive within a single sample. Sedimentary conditions which favour the development of a strong sulphate reduction zone, and hence the formation of pyrite, do not favour the formation of a strong sub-oxic zone, where siderite is preferentially precipitated, and vice versa. There is a strong facies control upon siderite formation, with ripple cross-laminated sands being most strongly siderite cemented.
Finite strain has no influence on the illite crystallinity of tectonized Eocene limestone breccias of the Morcles nappe, Swiss Alps
Authors: Burkhard M. , Badertscher N.
Published: July 2002

The relationship between illite crystallinity (IC) and finite strain as well as lattice strain and crystallite size of illite is examined in a series of 27 deformed breccia samples from the inverted limb of the Morcles nappe. The IC is determined independently for limestone components and a red/green clay-silt matrix. The finite strain varies widely (D= 0.8–2.5). The IC values vary from diagenetic to epizonal, but no correlation with finite strain could be established. The spread of IC values is explained by heterogeneities within the protolith which have not been homogenized/ obliterated by the anchizonal to epizonal metamorphic overprint. While limestone pebbles display IC values in agreement with the regional metamorphic conditions, the clay-silt matrix has anomalously high IC values, even after deconvolution of the 10 Å peak to correct for the presence of paragonite/muscovite. No correlation could be established between finite strain, lattice strain and/or crystallite size of illite.
The origin of iridescence in anthophyllite-gedrite from Simiuttat, Nuuk district, southern West Greenland
Authors: Champness P. E. , Rodgers K. A.
Published: July 2002

The golden iridescence observed in orthoamphiboles from the Nuuk district, southern West Greenland has been shown by analytical transmission electron microscopy to be the result of the interference of light reflected from alternate, coherent gedrite and anthophyllite exsolution lamellae parallel to (010). The lamellae are periodic with an average spacing of ∼180 nm; lamellae with this spacing would give rise to yellow iridescence. It is concluded that the exsolution lamellae are the origin of the features previously seen on cleaved surfaces of the amphiboles in the atomic force microscope (AFM). The suggestion is that the 0.75° difference in the cleavage angle for the two phases produces corrugations that are imaged by AFM. The morphology of the lamellae is consistent with an origin by spinodal decomposition.
Aluminium in quartz as an indicator of the temperature of formation of agate
Authors: Götze J. , Plötze M. , Tichomirowa M. , Fuchs H. , Pilot J.
Published: July 2002

An ‘Al-thermometer’ was applied to agate samples of volcanic parent rocks to provide information about the temperature of agate formation. The temperatures were calculated from concentrations of [AlO4]0 centres determined by electron paramagnetic resonance (EPR) measurements. The calculations for agate bands in some cases yield temperatures of up to 655°C, which are assumed to be invalid; they are thought to be artifacts resulting from non-equilibrium crystallization processes. In contrast, the formation temperatures (60–198°C) estimated for associated quartz incrustations within the agate geodes are in good accord with those calculated from oxygen isotope data. Direct estimation of the formation temperatures of agates is problematic. The best results will be obtained by analyses of associated phanerocrystalline quartz incrustations.
Goldmanite from the black slates of the Ogcheon belt, Korea
Authors: Jeong G. Y. , Kim Y. H.
Published: July 2002

Goldmanite, the vanadium analogue of grossular and andradite, was found as subrounded green porphyroblasts ranging from 0.1 to 1.7 mm in size in the carbonaceous black slates from the Deokpyeong area of the Ogcheon belt in Korea. A radiating aggregate of slightly curved blades of goldmanite crystals displays birefringence and replaces the fine-grained black matrix. The V2O3 content ranges from 21.9 to 26.6 wt.% (24.0 wt.% average), higher than previously reported values. The calculated mole % of the goldmanite end-member ranges from 72 to 91. Its cell dimension was calculated to be 12.04 Å from X-ray diffraction. The black slate in the Deokpyeong area is the richest known accessible source of relatively pure goldmanite.
Loparite and ‘metaloparite’ from the Burpala alkaline complex, Baikal Alkaline
Province (Russia)
Authors: Chakhmouradian A. R. , Mitchell R. H. , Pankov A. V. , Chukanov N. V.
Published: July 2002

Loparite-(Ce) is a ubiquitous accessory mineral in modally diverse
albite-rich metasomatic rocks of the Burpala alkaline complex, Siberia.
Compositionally, the mineral approaches the ideal formula
NaREETi2O6
(REE = Ce > La > Nd > Pr > Sm), and
contains minor CaTiO3 (<4.8 mol.%),
SrTiO3 (<4.7 mol.%) and NaNbO3
(<6.4 mol.%), The mineral is pseudocubic
[ap = 3.8815(3) Å], and
produces an XRD pattern similar to that of synthetic
NaCeTi2O6
[Pnma, a = 5.4517(4),
b = 7.7058(9), c =
5.4333(6) Å]. The atomic coordinates and isotropic thermal parameters of synthetic
NaCeTi2O6 refined from an XRD powder
pattern using the Rietveld method, are given. At Burpala, loparite precipitated
from an alkaline REE-rich fluid during the metasomatic
alteration of earlier-formed intrusive rocks. In some parageneses, loparite was
replaced by ‘metaloparite’ during the final stages of metasomatism. ‘Metaloparite’
has the empirical formula
REETi2O6-x(OH,F)x·nH2O,
and shows minor enrichment in Ca and depletion in Sr, compared to co-existing
loparite. The formation of ‘metaloparite’ involved cation leaching, hydration and
ion-exchange between loparite and a fluid. ‘Metaloparite’ is metamict at room
temperature, but some samples regain the perovskite-type structure upon
heating.
Controlled trial of filgrastim for acceleration of neutrophil recovery after allogeneic blood stem cell transplantation from human leukocyte antigen–matched related donors
Authors: Przepiorka Donna , Smith Terry L. , Folloder Jody , Anderlini Paolo , Chan Ka-Wah , Körbling Martin , Lichtiger Benjamin , Norfleet Frank , Champlin Richard
Published: July 2002

The rapid recovery of hematopoiesis after allogeneic blood stem cell transplantation has been attributed to the quality and quantity of hematopoietic progenitors in the blood stem cell grafts from filgrastim-stimulated donors. To determine whether further stimulation with filgrastim after transplantation would affect hematopoietic recovery, a prospective, randomized, controlled study was performed. Forty-two adult recipients of allogeneic blood stem cells from human leukocyte antigen-matched related donors were randomized to receive 10 μg/kg per day filgrastim subcutaneously from day 1 through neutrophil recovery or no growth factor support after transplantation. There was no significant difference between the 2 groups in the number of CD34+ cells infused (median, 4.8 vs 4.3 × 106/kg). Graft-versus-host (GVHD) disease prophylaxis consisted of tacrolimus and steroids for 9 patients and tacrolimus and minimethotrexate for 33 patients. The group receiving filgrastim had a shorter time to neutrophil levels greater than 0.5 × 109/L (day 12 vs day 15, P = .002) and to neutrophil levels greater than 1.0 × 109/L (day 12 vs day 16, P = .01). The filgrastim group also had a trend for earlier discharge (day 16 vs 20, P = .05). There was no significant difference between the groups in time to platelet recovery, number of transfusions, regimen-related toxicity, infection, incidence of GVHD, relapse, survival, or hospital charges. It can be concluded that the administration of filgrastim after allogeneic blood stem cell transplantation shortens the time to neutrophil recovery.
Verotoxin-1–induced up-regulation of adhesive molecules renders microvascular endothelial cells thrombogenic at high shear stress
Authors: Morigi Marina , Galbusera Miriam , Binda Elena , Imberti Barbara , Gastoldi Sara , Remuzzi Andrea , Zoja Carla , Remuzzi Giuseppe
Published: July 2002

Verotoxin-1 (VT-1)–producing Escherichia coli is the causative agent of postdiarrheal hemolytic uremic syndrome (D+HUS) of children, which leads to renal and other organ microvascular thrombosis. Why thrombi form only on arterioles and capillaries is not known. This study investigated whether VT-1 directly affected endothelial antithrombogenic properties promoting platelet deposition and thrombus formation on human microvascular endothelial cell line (HMEC-1) under high shear stress. Human umbilical vein endothelial cells (HUVECs) were used for comparison as a large-vessel endothelium. HMEC-1 and HUVECs were pre-exposed for 24 hours to increasing concentrations of VT-1 (2-50 pM) and then perfused at 60 dynes/cm2 with heparinized human blood prelabeled with mepacrine. Results showed that VT-1 significantly increased platelet adhesion and thrombus formation on HMEC-1 in comparison with unstimulated control cells. An increase in thrombus formation was also observed on HUVECs exposed to VT-1, but to a remarkably lower extent. The greater sensitivity of HMEC-1 to the toxin in comparison with HUVECs was at least in part due to a higher expression of VT-1 receptor (20-fold more) as documented by FACS analysis. The HMEC-1 line had a comparable susceptibility to the thrombogenic effect of VT-1 as primary human microvascular cells of the same dermal origin (HDMECs). The adhesive molecules involved in VT-induced thrombus formation were also studied. Blocking the binding of von Willebrand factor to platelet glycoprotein Ib by aurintricarboxylic acid (ATA) or inhibition of platelet αIIbβ3-integrin by chimeric 7E3 Fab resulted in a significant reduction of VT-1–induced thrombus formation, suggesting the involvement of von Willebrand factor–platelet interaction at high shear stress in this phenomenon. Functional blockade of endothelial β3-integrin subunit, vitronectin receptor, P-selectin, and PECAM-1 with specific antibodies was associated with a significant decrease of the endothelial area covered by thrombi. Confocal microscopy studies revealed that VT-1 increased the expression of vitronectin receptor and P-selectin and redistributed PECAM-1 away from the cell-cell border of HMEC-1, as well as of HDMECs, thus indicating that the above endothelial adhesion molecules are directly involved and possibly determine the effect of VT-1 on enhancing platelet adhesion and thrombus formation in microvascular endothelium. These results might help to explain why thrombi in HUS localize in microvessels rather than in larger ones and provide insights on the molecular events involved in the process of microvascular thrombosis associated with D+HUS.
Sustained multilineage gene persistence and expression in dogs transplanted with CD34+ marrow cells transduced by RD114-pseudotype oncoretrovirus vectors
Authors: Goerner Martin , Horn Peter A. , Peterson Laura , Kurre Peter , Storb Rainer , Rasko John E. J. , Kiem Hans-Peter
Published: July 2002

Previous studies have shown that the choice of envelope protein (pseudotype) can have a significant effect on the efficiency of retroviral gene transfer into hematopoietic stem cells. This study used a competitive repopulation assay in the dog model to evaluate oncoretroviral vectors carrying the envelope protein of the endogenous feline virus, RD114. CD34-enriched marrow cells were divided into equal aliquots and transduced with vectors produced by the RD114-pseudotype packaging cells FLYRD (LgGLSN and LNX) or by the gibbon ape leukemia virus (GALV)–pseudotype packaging cells PG13 (LNY). A total of 5 dogs were studied. One dog died because of infection before sustained engraftment could be achieved, and monitoring was discontinued after 9 months in another animal that had very low overall gene-marking levels. The 3 remaining animals are alive with follow-ups at 11, 22, and 23 months. Analyses of gene marking frequencies in peripheral blood and marrow by polymerase chain reaction revealed no significant differences between the RD114 and GALV-pseudotype vectors. The LgGLSN vector also contained the enhanced green fluorescent protein (GFP), enabling us to monitor proviral expression by flow cytometry. Up to 10% of peripheral blood cells expressed GFP shortly after transplantation and approximately 6% after the longest follow-up of 23 months. Flow cytometric analysis of hematopoietic subpopulations showed that most of the GFP-expressing cells were granulocytes, although GFP-positive lymphocytes and monocytes were also detected. In summary, these results show that RD114-pseudotype oncoretroviral vectors are able to transduce hematopoietic long-term repopulating cells and, thus, may be useful for human stem cell gene therapy.
Genetic polymorphism in exon 4 of cytochrome P450 CYP2C9 may be associated with warfarin sensitivity in Chinese patients
Authors: Leung Anskar Y. H. , Chow Howard C. H. , Kwong Y. L. , Lie Albert K. W. , Fung Alvin T. K. , Chow W. H. , Yip Alex S. B. , Liang Raymond
Published: July 2002

CYP2C9 polymorphisms reported in Caucasians (Arg144Cys in exon 3 and Ile359Leu in exon 7) are extremely uncommon in Chinese persons. The genotype of CYP2C9 in this population was characterized to investigate its relation with the interindividual variation in warfarin dosages. Eighty-nine Chinese patients receiving warfarin were recruited. Target sequences inCYP2C9 in exons 1, 4, and 5 were amplified by polymerase chain reaction, followed by direct sequencing. Polymorphisms at 4 positions were demonstrated in exon 4. Heterozygosities for 608TTG>GTG (Leu208Val), 561CAG>CCG (Gln192Pro), 537CAT>CCT (His184Pro), and 527ATT>CTT (Ile181Leu) existed at frequencies 0.75, 0.20, 0.10, and 0.09, respectively. Seventeen patients (frequency, 0.19) were homozygous for Val208. The common genotypic combinations at these loci are Ile181/His184/Gln192/Leu208Val (n = 50), Ile181/His184/Gln192/Val208 (n = 15), Ile181/His184/Gln192/Leu208 (n = 4), Ile181/His184/Gln192Pro/Leu208Val (n = 6), Ile181/His184Pro/Gln192Pro/Leu208Val (n = 4), and Ile181Leu/His184/Gln192Pro/ Leu208Val (n = 4). At codon 208, heterozygous Leu208Val and homozygous Val208 appeared to have a lower warfarin dose requirement than the homozygous Leu208. Patients who are heterozygous for Ile181Leu had a higher warfarin dose requirement than the homozygous Ile181. Amplified sequences in exons 1 and 5 did not exhibit polymorphism. In conclusion, Chinese patients showed genetic polymorphisms of CYP2C9 in exon 4 and at codon 208; most were heterozygous Leu208Val and homozygous Val208. Homozygous Leu208, a common allele in Caucasians, is uncommon in this cohort. The significance of these CYP2C9 polymorphic alleles remains to be determined.
Treatment of chronic myelogenous leukemia with the tyrosine kinase inhibitor STI571 results in marked regression of bone marrow fibrosis
Authors: Beham-Schmid Christine , Apfelbeck Ute , Sill Heinz , Tsybrovsky Oleksiy , Höfler Gerald , Haas Oskar A. , Linkesch Werner
Published: July 2002

Morphologic bone marrow changes in patients with BCR-ABL–positive chronic myelogenous leukemia (CML) were investigated during treatment with the tyrosine kinase inhibitor STI571. Bone marrow trephine biopsy specimens from 23 pretreated patients with CML were examined morphologically and by morphometry before and 6 weeks and 3 months after the initiation of STI571 therapy (Glivec, Novartis, Basel, Switzerland). Bone marrow changes during treatment showed a quantitative normalization of erythropoiesis, a marked reduction of granulopoiesis, and a significant decrease in megakaryocytes with the reappearance of normal-sized forms. Furthermore, a significant regression of bone marrow fibrosis was observed in patients with initial fibrosis (P < .000 000 001). These results may expand the profile of STI571 and may offer novel therapeutic possibilities in diseases with bone marrow fibrosis.
Retrovirus-mediated gene transfer in primary T lymphocytes impairs their anti–Epstein-Barr virus potential through both culture-dependent and selection process–dependent mechanisms
Authors: Sauce Delphine , Bodinier Marie , Garin Marina , Petracca Bruno , Tonnelier Nicolas , Duperrier Anne , Melo Junia V. , Apperley Jane F. , Ferrand Christophe , Hervé Patrick , Lang François , Tiberghien Pierre , Robinet Eric
Published: July 2002

To modulate alloreactivity after hematopoietic stem cell transplantation, suicide gene–expressing donor T cells can be administered with an allogeneic T-cell–depleted bone marrow graft. Immune competence of such cells is a critical issue. The impact of the ex vivo gene transfer protocol (12-day culture period including CD3/interleukin-2 [IL-2] activation, retroviral-mediated gene transfer, and G418-based selection) on the anti–Epstein-Barr virus (EBV) potential of gene-modified cells has been examined. Cytotoxic (pCTL) and helper (pTh) cell precursor limiting dilution assays, interferon-γ enzyme-linked immunospot, or fluorescence-activated cell sorter analysis after tetrameric HLA-A2/EBV peptide complexes revealed that the frequency of anti-EBV T cells was lower in gene-modified cells (GMCs) than in similarly cultured but untransduced T cells and was even lower than in fresh peripheral blood mononuclear cells, demonstrating both an effect of the culture and of the transduction or selection. The culture-dependent loss of EBV-reactive cells resulted from the preferential induction of activation-induced cell death in tetramer+ cells. Replacing the initial CD3/IL-2 activation by CD3/CD28/IL-2 partially restored the anti-EBV response of GMCs by reducing the initial activation-induced cell death and enhancing the proliferation of EBV-tetramer+cells. Moreover, the G418 selection, and not the transduction, was directly toxic to transduced tetramer+ cells. Replacing the G418 selection by an immunomagnetic selection significantly prevented the selection-dependent loss of EBV-specific cells. Overall, ex vivo gene modification of primary T cells can result in a significant reduction in EBV-reactive T cells through both culture-dependent and selection-dependent mechanisms. Improving immune functions of GMCs through modifications of the cell culture conditions and transduction/selection processes is critical for further clinical studies.
Abnormally spliced β-globin mRNAs: a single point mutation generates transcripts sensitive and insensitive to nonsense-mediated mRNA decay
Authors: Danckwardt Sven , Neu-Yilik Gabriele , Thermann Rolf , Frede Ute , Hentze Matthias W. , Kulozik Andreas E.
Published: July 2002

Nonsense-mediated mRNA decay (NMD) represents a phylogenetically widely conserved splicing- and translation-dependent mechanism that eliminates transcripts with premature translation stop codons and suppresses the accumulation of C-terminally truncated peptides. Elimination of frameshifted transcripts that result from faulty splicing may be an important function of NMD. To test this hypothesis directly, this study used the IVS1 + 5 G>A thalassemia mutation of the human β-globin gene as a model system. We generated β-globin gene constructs with this mutation and an iron-responsive element in the 5′ untranslated region, which allowed specific experimental activation and inactivation of translation and, hence, NMD of this transcript. Premessenger RNAs with IVS1 + 5 G>A were spliced at normal sites and cryptic sites, enabling a direct comparison of the effect of NMD on the accumulation of normal and frameshifted messenger RNAs. In transfected HeLa cells, the predominant frameshifted transcript was degraded under conditions of active NMD, whereas accumulation to high levels occurred under conditions of specifically disabled NMD, thereby indicating an important physiologic function of NMD in the control of the splicing process. An unexpected finding was that accumulation of a second aberrant transcript remained unaffected by NMD. The IVS1 + 5 G>A mutation thus revealed the presence of an unknown cis-acting determinant that influences the NMD sensitivity of a putative NMD substrate. It can therefore serve as a useful tool for defining the mechanisms that permit specific transcripts to circumvent the NMD pathway.
Method effects on reading comprehension test performance: text organization and response format
Authors: Kobayashi Miyoko
Published: July 2002

If tests are to provide an accurate measure of learners’ language abilities, examiners must minimize the influence of intervening factors such as text organization and response format on test results. The purpose of this article is to investigate the effects of these two factors on second language learners’ performance in reading comprehension tests. The study analyses the results of reading comprehension tests which were delivered to 754 Japanese university students. The main finding is that text organization and test format had a significant impact on the students’ performance. When texts were clearly structured, the more proficient students achieved better results in summary writing and open-ended questions. By contrast the structure of the text made little difference to the performance of the less proficient students. This suggests that well-structured texts make it easier to differentiate between students with different levels of proficiency. Examiners have hitherto taken little notice of the impact of text structure and test format on students’ results. By paying more attention to these factors, they will enhance the validity of their tests.
Pitfalls in effectiveness research: a comparative analysis of treatment goals and outcome measures in stroke rehabilitation
Authors: Lettinga A T , Reynders K , Mulder T H , Mol A
Published: July 2002

Problem: There is a great diversity of movement therapies in stroke rehabilitation, each of which is treated as a more or less independent system.

Objective: To articulate pitfalls in effectiveness research that has been employed to reduce the number of different forms of treatment.

Methods: The contents of treatment goals and outcome measures in clinical and scienti”c texts on stroke rehabilitation were analysed and contrasted in order to uncover discrepancies.

Issues: The main issue is that theory and conceptualization of therapy play a diminished role in treatment effectiveness research, which may hinder the interpretation of data. The notion that the methodological and statistical tools, if correctly applied, provide researchers with the distance that is thought to be necessary for an objective judgement will be challenged.

Conclusion: The analyses indicate that although scienti”cally credible measurement tools may be neutral with regard to the user, they are not necessarily neutral with regard to the therapies being compared in effectiveness research.
A 1400-year high-resolution record of atmospheric circulation over the North Atlantic and Asia
Authors: Meeker Loren D. , Mayewski Paul A.
Published: July 2002

Major ion series developed from new subannual scale sampling of an ice core from central Greenland are calibrated with instrumental series of atmospheric sea-level pressure recording major marine (Icelandic Low) and terrestrial (Siberian High) atmospheric circulation systems to provide proxy records of atmospheric circulation over the past 1400 years. Examination of the proxy records reveals: major changes in behaviour of these systems c. ad 1400, multidecadal- and centennial-scale periodic components, characterization of mean sea-level pressure anomaly fields during the ‘Little Ice Age’ and the ‘Mediaeval Warm Period’, the potential role of solar forcing, coupled ocean-atmosphere associations, and a perspective within which the characteristics of instrumental-era climate can be assessed.
Oophorectomy and Tamoxifen Adjuvant Therapy in Premenopausal Vietnamese and Chinese Women With Operable Breast Cancer
Authors: Love Richard R. , Duc Nguyen Ba , Allred D. Craig , Binh Nguyen Cong , Dinh Nguyen Van , Kha Nguyen Ngoc , Thuan Tran Van , Mohsin Syed K. , Roanh Le Dinh , Khang Hoang Xuan , Tran Trinh Luong , Quy Tran Tu , Thuy Nguyen Van , Thé Pham Nhu , Cau Ton That , Tung Nguyen Dinh , Huong Dang Thanh , Quang Le Minh , Hien Nguyen Ngoc , Thuong Le , Shen Tian-zhen , Xin Ye , Zhang Qian , Havighurst Thomas C. , Yang Yonghong Fred , Hillner Bruce E. , DeMets David L.
Published: July 2002

PURPOSE: In 1992, the Early Breast Cancer Trialists’ Collaborative Group reported that a meta-analysis of six randomized trials in European and North American women begun from 1948 to 1972 demonstrated disease-free and overall survival benefit from adjuvant ovarian ablation. Approximately 350,000 new cases of breast cancer are diagnosed annually in premenopausal Asian women who have lower levels of estrogen than western women.

PATIENTS AND METHODS: From 1993 to 1999, we recruited 709 premenopausal women with operable breast cancer (652 from Vietnam, 47 from China) to a randomized clinical trial of adjuvant oophorectomy and tamoxifen (20 mg orally every day) for 5 years or observation and this combined hormonal treatment on recurrence. At later dates estrogen- and progesterone-receptor protein assays by immunohistochemistry were performed for 470 of the cases (66%).

RESULTS: Treatment arms were well balanced. With a median follow-up of 3.6 years, there have been 84 events and 69 deaths in the adjuvant treatment group and 127 events and 91 deaths in the observation group, with 5-year disease-free survival rates of 75% and 58% (P = .0003 unadjusted; P = .0075 adjusted), and overall survival rates of 78% and 70% (P = .041 unadjusted) for the adjuvant and observation groups, respectively. Only patients with hormone receptor–positive tumors benefited from the adjuvant treatment. In Vietnam, for women unselected for hormone receptor status, a cost-effectiveness analysis suggests that this intervention costs $350 per year of life saved.

CONCLUSION: Vietnamese and Chinese women with hormone receptor–positive operable breast cancer benefit from adjuvant treatment with surgical oophorectomy and tamoxifen.
Susceptibility of ribosomes of the tetracycline‐producing strain of Streptomyces aureofaciens to tetracyclines
Authors: Mikulík Karel , Jiráňová Anna , Janda Ivan , Weiser Jaroslav
Published: July 2002

Ribosomes from cells of Streptomyces aureofaciens producing tetracycline antibiotics (Tc‐ribosomes) differ in electrophoretic mobility of ribosomal proteins S2, S10 and L19 from those of the same strain, where the production of tetracyclines was suppressed by changed cultivation conditions (C‐ribosomes). Purified tight vacant couples C‐ and Tc‐ribosomes are equally active in the translation of poly(U). Both types of S. aureofaciens ribosomes are more sensitive to tetracycline and chlortetracycline than ribosomes of Escherichia coli in the Phe‐tRNA binding and the translation of poly(U).
The transverse membrane orientation of the light‐harvesting and reaction centre polypeptides of Rhodopseudomonas capsulata, investigated by surface iodination
Authors: Peters Jürgen D. , Drews Gerhart
Published: July 2002

The transverse orientation of photosynthetic polypeptides in the membrane of Rhodopseudomonas capsulata was investigated using surface radioiodination of chromatophores and spheroplasts with the reagent 1,3,4,6‐tetrachloro‐3α, 6α‐diphenylglycoluril. Native pigment‐protein complexes were isolated by Triton X‐100‐polyacrylamide gel electrophoresis to identify and distinguish polypeptides not separated by sodium dodecylsulphate‐polyacrylamide gel electrophoresis. The two antenna light‐harvesting complexes were found to be asymmetrically oriented with polypeptides 14 kDa and 8 kDa of complex B800‐850 and 12 kDa of B870 being exposed on either membrane surface. Subunits H and M of the photochemical reaction centre, and probably L, span the membrane.
Interaction of nucleic acids with the DNA‐dependent RNA polymerases of Drosophila
Authors: Gundelfinger Eckart D.
Published: July 2002

The interaction between the three Drosophila DNA‐dependent RNA polymerases (EC 2.7.7.6) and the DNA template or the RNA product was investigated by photochemical cross‐linking and binding studies, using RNA polymerase subunits immobilized on nitro‐cellulose filters. It can be shown that the two largest subunits are responsible for the binding of the enzymes to both template and newly‐synthesized RNA.
On a non‐pyridine nucleotide‐dependent 2‐oxo‐acid reductase of broad substrate specificity from two Proteus species
Authors: Neumann Stefan , Simon Helmut
Published: July 2002

Proteus mirabilis and Proteus vulgaris contain in the crude extract a non‐pyridine nucleotide dependent reductase for 2‐oxo‐acids as well as 2‐oxo‐dicarboxylic acids of specific activities of 1–10 units/mg protein. The enzyme catalyzes the reduction of very different 2‐oxo‐acids to the corresponding (2R)‐hydroxy‐acid. Reduced methyl‐ or benzylviologen act as artifical electron donors. The membrane‐bound enzyme has been enriched 167‐fold to a purity 90% as judged by electrophoresis. It seems that the enzyme does not contain flavin.
Action of two alkaline proteases and a trypsin inhibitor from white croaker skeletal muscle (Micropogon opercularis) in the degradation of myofibrillar proteins
Authors: Folco E.J. , Busconi L. , Marione C. , Trucco R.E. , Sánchez J.J.
Published: July 2002

The action of two alkaline proteases from white skeletal muscle on myofibrillar proteins is shown. Purified myosin was readily degraded by both proteases, but only protease I was able to degrade myosin heavy chain from actomyosin. The effect of inhibitor on both proteases was also studied. The activity of protease II on azocasein was not affected, while the action of protease I on both azocasein and myosin was inhibited. The implication of proteases and inhibitor on the turnover of myofibrillar proteins is considered.
Crystallization of the photosynthetic light‐harvesting pigment‐protein complex B800‐850 of Rhodopseudomonas capsulata
Authors: Welte Wolfram , Wacker Thomas , Leis Monika , Kreutz Werner , Shiozawa Judith , Gad'on Nasser , Drews Gerhart
Published: July 2002

The B800‐850 light‐harvesting complex of Rhodopseudomonas capsulata was crystallized in the presence of detergents. The crystals were obtained by a vapour diffusion technique, using polyethylene glycol as a precipitant. Crystals grew to a size of 0.5 × 0.5 × 0.3 mm within two weeks. Two different crystal forms were obtained; one is supposed to be triclinic, space group PI, the other orthorhombic, space group C2221. Both crystal forms diffract to approximately 1.0 nm. Absorption spectra and polyacrylamide gel electrophoresis demonstrate that all expected components, i.e. three polypeptides of apparent M
r,8000, 10000 and 14000, bacteriochlorophyll a and carotenoids, are present and in native conformation.
Isolation and characterization of dipeptidyl peptidase IV from human meconium
Authors: Caporale Carlo , Fontanella Angiola , Petrilli Pasquale , Pucci Piero , Molinaro Maria Francesca , Picone Delia , Auricchio Salvatore
Published: July 2002

Dipeptidyl aminopeptidase IV (DAP‐IV) (EC 3.4.14.1) was purified from meconium particles sedimenting at 105000 × g. Its molecular properties and activity on synthetic and natural substrates (casomorphin and procasomorphin) were investigated.
Effect of asorbic acid on secreted proteoglycans from rabbit articular chondrocytes
Authors: Jouis Veronique , Bocquet Jean , Pujol Jean-Pierre , Brisset Martine , Loyau Gerard
Published: July 2002

Addition of ascorbic acid (25, 50 100 ) to cultures of rabbit articular chondrocytes did not change the total amount of proteoglycans produced. However, it induced an increased retention of these macromolecules in the pericellular fraction. The size of the proteoglycan subunits and the length of glycosaminoglycan chains, released in the medium, were not modified on exposure to ascorbic acid (25 ). On the other hand, the rate of non‐sulfated chondroitin was increased 2.5‐fold, whereas chondroitin‐4‐sulfate was depressed 1.5‐fold.
Biochemical analysis of bovine testicular anti‐Müllerian hormone
Authors: Picard Jean-Yves , Goulut Chantal , Bourrillon R. , Josso Nathalie
Published: July 2002

Direct biochemical analysis has been applied to bovine testicular anti‐Müllerian hormone (AMH), purified from incubation medium of bovine fetal testes by immunochromatography on a monoclonal antibody. The hormone contains a high proportion of hydrophobic amino acids and 13.5% carbohydrate. The oligosaccharide composition suggests that both N‐ and O‐glycosidically linked chains are present. The molecular extinction coefficient is 3.27 ± 0.06. One RIA unit, defined as the amount of hormone released by 1 g fetal bovine testicular tissue incubated during 4 h, corresponds to 3.06 ± 0.17 /smg protein.
Leukotriene B4 stimulation of phosphatidylinositol turnover in macrophages and inhibition by pertussis toxin
Authors: Holian Andrij
Published: July 2002

The influence of leukotriene B4 (LTB4) on phosphatidylinositol (PI) cycle activity was investigated in the guinea pig alveolar macrophage. In contrast to the observation reported in leukocytes [(1984) Proc. Natl. Acad. Sci. USA 81, 5966‐5969], LTB4 was found to stimulate PI cycle activity in the macrophage (transient decrease in phosphatidylinositol 4,5‐bisphosphate and phosphatidylinositol 4‐phosphate, transient elevation of 1,2‐diacylglycerol and elevation of phosphatidic acid) similar to the stimulation of the PI cycle by the chemotactic formyi peptides. Preincubation of macrophages with 1 μ/ml of pertussis toxin, for 1 h at 37°C, blocked LTB4 and formyl peptide stimulated O2
− production and PI cycle activity. Therefore, both stimulants are proposed to act through the same coupling protein to activate phospholipase C in the early stages of macrophage activation.
The synergistic effect of serotonin and epinephrine on the human platelet at the level of signal transduction
Authors: de Chaffoy de Courcelles D. , Roevens P. , Van Belle H. , De Clerck F.
Published: July 2002

Simultaneous addition to platelets of submaximal amounts of excitatory agonists acts synergistically in provoking secretory and aggregatory responses. By measuring changes in intracellular free Ca2+ concentration, inositol phospholipid metabolism and protein phosphorylation, we verified whether synergism could be evidenced at the level of signal transduction. Challenging platelets with epinephrine only induced minor changes on the measured parameters. However, when added together with serotonin, epinephrine amplified mobilisation of intracellular C2+, PA formation, PIP formation, protein kinase C and myosin light chain kinase activity as compared to the alterations induced by serotonin alone. It is concluded that synergistic effects on simultaneous addition of serotonin and epinephrine might originate at the level of signal transduction.
Release of repetitive transient potentials and opening of potassium channels by barium in Eremosphaera viridis
Authors: Thaler Manfred , Steigner Wieland , Köhler Kurt , Simonis Wilhelm , Urbach Wolfgang
Published: July 2002

A concentration‐dependent effect of Ba2+ on voltage‐independent opening of K+ channels in Eremosphaera was examined. Low concentrations of external Ba2+ (10−2mM) cause the release of repetitive transient potentials. Higher concentrations of Ba2+, however, inhibit these Ba2+‐induced repetitive and also light‐off triggered transient potentials. Experiments with different Ca2+ concentrations in the medium and the treatment with La3+ suggest the interaction of Ba2+ with Ca2+ channels and the participation of internal Ca2+ in the activation of K+ channels.
Biotransformation of aromatic compounds Monitoring fluorinated analogues by NMR
Authors: Cass Anthony E.G. , Ribbons Douglas W. , Rossiter John T. , Williams Steve R.
Published: July 2002

The results presented here illustrate the power of NMR in the non‐invasive analysis of microbial transformations. Whilst the definitive identification of products requires purification and full structural elucidation, NMR can provide rapid insights into the nature of these reactions and their regulation in vivo. In addition, once the products have been identified NMR methods allow rapid assessment of the effects of genetic and physiological manipulation, and on competing metabolic fluxes with mixed substrates and branched pathways.
Thyroid hormones regulate expression of the neural cell adhesion molecule in adult skeletal muscle
Authors: Thompson Joanne , Moore Stephen E. , Walsh Frank S.
Published: July 2002

Adult rat skeletal muscle does not express detectable levels of neural cell adhesion molecule (N‐CAM) and membrane activity mediated by nerve appears to repress the N‐CAM gene. N‐CAM expression in skeletal muscle can however be reinduced by hypothyroidism. Thyroidectomised rats re‐express N‐CAM mRNAs of 5.2 and 2.9 kb and Western blot analysis showed protein bands of 125 and 155 kDa. Immunofluorescence analysis also showed high levels of N‐CAM in the sarcolemma. These changes in N‐CAM expression could be reversed by treatment of hypothyroid rats with thyroxine. Thus thyroid hormones as well as neural influences appear to control N‐CAM expression in skeletal muscle.
Temporal changes in intracellular distribution of protein kinase C during differentiation of human leukemia HL60 cells induced by phorbol ester
Authors: Kiss Zoltan , Deli Eva , Kuo J.F.
Published: July 2002

Immunocytochemical methods were used to study protein kinase C (PKC) distribution in HL60 cells during the entire course of 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐induced differentiation. After an initial translocation of PKC from cytoplasm to plasma membrane, the enzyme was localized close to the nuclear membrane region at day 1 of TPA treatment. PKC was associated with nuclei at day 2 and with nuclei, cytoplasm and plasma membrane at days 3 and 5. Attachment of cells to substratum (day 2) was accompanied by increased phosphorylation of several nuclear proteins. At day 7, the differentiated cells became detached and PKC in these cells was largely cytoplasmic. In view of the crucial role of PKC in cell differentiation, it is expected that changes in its intracellular localization have physiological significance.
Rapid transducin deactivation in intact stacks of bovine rod outer segment disks as studied by light scattering techniques Arrestin requires additional soluble proteins for rapid quenching of rhodopsin catalytic activity
Authors: Wagner Rafael , Ryba Nicholas , Uhl Rainer
Published: July 2002

In photoreceptors of the living retina both activation and deactivation of transducin must occur in less than 1 s. In ROS preparations used for in vitro studies, however, deactivation takes minutes. This is due to the fact that activated transducin is released into the free aqueous space, whereby GTPase activity and consequent deactivation of the protein are slowed down, and due to the dilution of soluble ROS proteins involved in the quenching of rhodopsin activity. In this paper, using a convenient, non‐invasive light scattering assay, we demonstrate that in an intact stack of disks, where active transducin stays membrane associated and is rapidly deactivated, the activity of rhodopsin can also be quenched in the time range of seconds when soluble ROS proteins are supplemented. Arrestin, the 48 kDa protein of the photoreceptor, is one of the proteins required for rapid recovery, however, it requires the synergistic action of other soluble proteins (besides rhodopsin kinase) in order to exert its effect: When arrestin is included in the reaction mixture without the ‘helper protein(s)’, it cannot speed recovery, and when a mixture of soluble proteins is added which lacks arrestin, there is also no effect. The nature and identity of this (these) helper protein(s) are still unclear.