bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wisconsin Glaciation of the Sierra Nevada (79,000–15,000 yr B.P.) as Recorded by Rock Flour in Sediments of Owens Lake, California
Authors: Bischoff James L. , Cummins Kathleen 
Published: September 2002

AbstractChemical analyses of the clay-sized fractions of 564 continuous sediment samples (200-yr resolution) from composite core OL90/92 allow quantification of an abundance of glacial rock flour. Rock flour produced during glacier advances is represented by clay-sized plagioclase, K-feldspar, and biotite in homogeneous internal composition. The abundance of rock flour is deemed proportional to the intensity of glacies advances. Age control for the composite section is provided by combining previously published radiocarbon dates on organics, U/Th dates on ostracode shells, and U/Th dates on saline minerals from nearby Searles Lake correlated to OL92 by pollen. The rock flour record displays three levels of variability: (1) a dominant one of about 20,000 yr related to summer insolation and precipitation; (2) an intermediate one of 3000–5000 yr, perhaps related to North Atlantic Heinrich events; and (3) a minor one of 1000–2000 yr, perhaps related to North Atlantic thermohaline-driven air-temperature variation.
Late Quaternary Upwelling Intensity and East Asian Monsoon Forcing in the South China Sea
Authors: Jian Zhimin , Huang Baoqi , Kuhnt Wolfgang , Lin Hui-Ling 
Published: September 2002

AbstractForaminifera from two cores off eastern Vietnam and the northwestern Philippines, where modern summer and winter monsoon-driven upwelling occurs in the South China Sea, respectively, were analyzed to evaluate the changes in paleoproductivity and upper water structure over the last 220,000 yr. We observed enhanced organic carbon flux and a shoaled thermocline when upwelling intensified off eastern Vietnam during interglacial ages and off the northwestern Philippines during glacial ages. This indicates that the East Asian summer monsoon increased while the winter monsoon decreased during interglacial ages. Particularly, the upwelling reached a maximum off eastern Vietnam during late marine isotopic stage (MIS) 5 and off the northwestern Philippines during MIS 2, implying that the summer monsoon decreased gradually since MIS 5 while the winter monsoon displayed an opposite trend. The variations in upwelling proxies exhibit a distinct cyclicity with frequencies near 41,000 yr and 23,000 yr off eastern Vietnam, in contrast to a strong frequency peak near 100,000 yr off the northwestern Philippines. We suggest that the East Asian summer monsoon has been forced by changes in solar insolation associated with precession and obliquity, while ice-volume forcing is probably a primary factor in determining the strength and timing of the East Asian winter monsoon but with less important insolation forcing.
Implications of a 24,000-Yr Palynological Record for a Younger Dryas Cooling and for Boreal Forest Development in Northeastern Siberia
Authors: Anderson Patricia M. , Lozhkin Anatoly V. , Brubaker Linda B. 
Published: September 2002

AbstractA sediment core from Smorodinovoye Lake (SML), northeastern Siberia (area to the east of the Verkhoyansk Range) spanning the last 24,000 14C yr indicates that vegetational and climatic changes in the upper Indigirka basin resemble those in eastern Siberia (Lena basin and westward). For example, maximum postglacial summer temperatures at SML probably occurred 6000–4000 14C yr B.P., an age more in accordance with eastern than northeastern records. Larix arrived near the lake by 9600 14C yr B.P., approximately when forests expanded in the east but ca. 1500 14C yr later than forests were established in the neighboring upper Kolyma basin. Paleobotanical data further suggest that Larix possibly migrated southward from populations in the arctic lowlands of eastern Siberia and did not originate from interior refugia of the upper Kolyma basin. Although a Younger Dryas cooling has been noted in eastern Siberia, SML provides the first evidence from the northeast for a similar climatic reversal. Climatic variations seemingly have persisted between the Indigirka and Kolyma basins over at least the last 11,000 14C yr, despite the proximity of the two drainages and the occurrence of major changes in boundary conditions (e.g., seasonal insolation, sea levels) that have influenced other regional climatic patterns.
Environments of the Russian Plain during the Middle Valdai Briansk Interstade (33,000–24,000 yr B.P.) Indicated by Fossil Mammals and Plants
Authors: Markova Anastasia K. , Simakova Alexandra N. , Puzachenko Andrei Yu , Kitaev Lev M. 
Published: September 2002

AbstractAbundant mammal (45 localities) and plant (52 sections) fossil data collected from the Russian Plain deposits of the Middle Valdai Briansk Interstade indicate a period of noticeable warming. These materials were jointly analyzed. The data were organized in the database software PARADOX and then moved to the GIS program ARC/INFO. Mathematical methods as well as traditional research methods were used for the analysis. The reconstructed biogeographical provinces illustrate the specific environmental and climatic conditions of the Briansk Interstade. Analogues of modern natural zones did not exist at this time on the Russian Plain. The Briansk landscapes reflect the moderate-cool climate of this period, when the majority of northern subarctic plant and mammal species extended their ranges considerably to the south to the Central Russian Plain. At the same time, steppe species penetrated farther north and west. This combination shows that the continuous forest zone was destroyed during the Briansk Inter-stade. Five biogeographical provinces have been reconstructed from the north to the south for the Russian Plain during the Briansk warming on the basis of joint analysis of mammalian and botanical data.
Charybdotoxin‐sensitive small conductance KCa channel activated by bradykinin and substance P in endothelial cells
Authors: Sollini M , Frieden M , Bény J‐L 
Published: September 2002

In cultured porcine coronary artery endothelial cells, we have recently shown that substance P and bradykinin stimulated different types of Ca2+‐dependent K+ (KCa) current. A large part of this current was insensitive to iberiotoxin and apamin. The aim of the present study was to characterize the KCa channel responsible for this current.
In cell‐attached configuration and asymmetrical K+ concentration, 100 nM bradykinin or substance P activated a 10 pS K+ channel. In inside‐out configuration, the channel was half‐maximally activated by 795 nM free Ca2+.
Apamin (1 μM) added to the pipette solution failed to inhibit the channel activity while charybdotoxin (50 nM), completely blocked it. Perfusion at the intracellular face of the cell, of an opener of intermediate conductance KCa channel, 500 μM 1‐ethyl‐benzimidazolinone (1‐EBIO) increased the channel activity by about 4.5 fold.
In whole‐cell mode, bradykinin and substance P stimulated an outward K+ current of similar amplitude. Charybdotoxin inhibited by 75% the bradykinin‐induced current and by 80% the substance P‐induced current. Charybdotoxin plus iberiotoxin (50 nM each) inhibited by 97% the bradykinin‐response. Charybdotoxin plus apamin did not increase the inhibition of the substance P‐response obtained in the presence of charybdotoxin alone.
1‐EBIO activated a transient outward K+ current and hyperpolarized the membrane potential by about 13 mV. Charybdotoxin reduced the hyperpolarization to about 3 mV.
Taken together these results show that bradykinin and substance P activate a 10 pS KCa channel, which largely contributes to the total K+ current activated by these agonists. Despite its small conductance, this channel shares pharmacological characteristics with intermediate conductance KCa channels.

British Journal of Pharmacology (2002) 136, 1201–1209. doi:10.1038/sj.bjp.0704819
Pharmacology and thermosensitivity of the dartos muscle isolated from rat scrotum
Authors: Gibson Alan , Akinrinsola Adetokunbo , Patel Tejesh , Ray Arijit , Tucker John , McFadzean Ian 
Published: September 2002

The dartos is a thin sheet of smooth muscle closely associated with the skin of the scrotum. Although known to play an important role in scrotal thermoregulation, there has been no detailed study into the pharmacology, or thermosensitivity, of the dartos from any species. Here, we investigate these two parameters in the isolated dartos muscle from rat.
Field stimulation of the rat dartos caused contractions that were abolished by tetrodotoxin, phentolamine and guanethidine, but unaffected by atropine or L‐NG‐nitroarginine. Exogenous noradrenaline also produced contractions blocked by both phentolamine and prazosin. In muscles with raised tone and negated sympathetic function, field stimulation failed to elicit relaxation. The dartos muscle did not contract in response to carbachol, nicotine, histamine, 5‐hydroxytryptamine (all up to 100 μM) or substance P (up to 1 μM).
Contractile responses to field stimulation and noradrenaline were much greater at 30°C compared with 40°C; indeed, contractions to 1 μM noradrenaline at 30°C were relaxed by around 80% on heating to 40°C. Similar heat‐induced relaxations were observed during contractions to both U46619 (100 nM) and high K (70 mM).
In contrast, contractile responses to the myosin phosphatase inhibitor calyculin‐A (1 μM), either in the presence or absence of external calcium, were resistant to relaxation by heating. In calcium‐free medium at 30°C, U46619 continued to produce contractions that were again relaxed by 80% on heating to 40°C. However, in the presence of calyculin‐A, this heat‐induced relaxation was greatly reduced.
Thus, the rat dartos muscle receives a functional sympathetic innervation and contracts to noradrenaline via α‐adrenoceptors. There is no functional inhibitory innervation. Experiments with calyculin‐A suggest that myosin phosphatase is a major contributor to the marked thermosensitivity of the dartos muscle.

British Journal of Pharmacology (2002) 136, 1194–1200. doi:10.1038/sj.bjp.0704830
Sphingosine 1‐phosphate enhances spontaneous transmitter release at the frog neuromuscular junction
Authors: Brailoiu Eugen , Cooper Robin L , Dun Nae J 
Published: September 2002

Intracellular recordings were made from isolated frog sciatic‐sartorius nerve‐muscle preparations, and the effects of sphingosine 1‐phosphate (S1‐P) on miniature endplate potentials (MEPPs) were studied. Extracellular application of S1‐P (1 and 30 μM) had no significant effects on the frequency and amplitude of MEPPs. Delivery into nerve terminals by liposomes containing 10−5, 10−4 or 10−3 M S1‐P was associated with a concentration‐dependent increase in MEPP frequency of 37, 63 and 86%. The per cent of median MEPP amplitude was not significantly changed, but there was an increase in the number of ‘giant’ MEPPs. Pre‐exposure of the preparations to S1‐P 10−5 but not 10−8 M entrapped in liposomes for 15 min blocked the effects of subsequent superfusion of S1‐P (10−4 M)‐filled liposomes on MEPP frequency. Thus, intracellular S1‐P receptors seem to undergo ‘desensitization’ to higher concentrations of S1‐P. The result provides the first evidence that S1‐P acting intracellularly but not extracellularly enhances spontaneous transmitter release at the frog neuromuscular junction.British Journal of Pharmacology (2002) 136, 1093–1097. doi:10.1038/sj.bjp.0704839
Validation of cytokeratin 5/6 as an effective substitute for keratin 903 in the differentiation of benign from malignant glands in prostate needle biopsies
Authors: Abrahams N A , Ormsby A H , Brainard J 
Published: September 2002

Aims:  Keratin 903 (also known as anti‐cytokeratin antibody 34βE12) is widely used to differentiate benign glands from malignant glands in prostate needle biopsies. However, it is subject to considerable staining heterogeneity. We sought to evaluate the use of cytokeratin 5/6 (CK5/6) as an effective alternative to K903 in the evaluation of prostate needle biopsies in clinical practice.Methods and results:  Thirty Hollandes‐fixed prostate needle biopsies were randomly selected over a period of 2 months from the surgical specimens accessioned over that period of time. Twelve cases had diagnosed prostatic adenocarcinoma (Gleason scores 3 + 3, 3 + 4 and 4 + 4) and the remaining cases (n = 18) were negative for carcinoma. Four sequential sections were stained with H&E (×2), K903, and CK5/6. Care was taken to preserve tissue so that matching glands were evaluated on all four sections. All cases were run routinely over a period of 3 weeks on a daily basis with matching positive controls. All slides were evaluated in a blinded fashion independently by two pathologists using a semiquantitative analysis of staining: <25%, 25–50%, 50–75%, >75% and >95% of benign glands (verified on H&E). Cases that showed no staining were repeated to ensure no false negatives. Both observers agreed with respect to percentage of staining in 96% of the cases. Twenty‐nine of 30 cases (97%) showed staining in >95% of benign glands with CK5/6. In contrast, K903 staining was seen in <50% of benign glands in five of 30 (17%), 50–75% in nine of 30 (30%), and >75% in 10 of 30 (33%), with only two cases (7%) showing >95% staining for K903. In four cases (13%) the K903 failed to stain any tissue even after repeat staining. K903 was conspicuously negative in atrophic glands in three of 30 cases (10%). Neither K903 nor CK5/6 stained malignant glands. Using a cut‐off of >75% staining in benign glands the sensitivity of CK5/6 and K903 was 97% and 40%, respectively.Conclusions:  CK5/6 has superior sensitivity and reliability compared with that of K903 when evaluating routine prostate needle biopsies, including improved staining of atrophic prostatic glands. While K903 is traditionally used to differentiate benign glands from malignant glands, these results support the use of CK5/6 as an effective and reliable substitute for K903 in routine clinical practice.
A Comparison of the Findings of Wrist Arthroscopy and Magnetic Resonance Imaging in the Investigation of Wrist Pain
Authors: MORLEY J. , BIDWELL J. , BRANSBY-ZACHARY M. 
Published: September 2002

Between 1996 and 1999, 54 patients with wrist pain had magnetic resonance imaging performed using a 1.5 Tesla scanner without a wrist coil. Wrist arthroscopy was performed using a standard technique. The findings were then compared. Magnetic resonance imaging had a low sensitivity for the detection of triangular fibrocartilage complex injuries (0.44) and scapholunate ligament injuries (0.11) when wrist arthroscopy was used as the standard of reference. We conclude that when a magnetoresonance technique that does not employ a dedicated wrist coil is used, a negative magnetic resonance imaging scan does not exclude these two significant injuries.
New insights into intracellular lipid binding proteins: The role of buried water
Authors: Lücke Christian , Huang Sinian , Rademacher Martin , Rüterjans Heinz 
Published: September 2002

AbstractThe crystal structures of most intracellular lipid binding proteins (LBPs) show between 5 and 20 internally bound water molecules, depending on the presence or the absence of ligand inside the protein cavity. The structural and functional significance of these waters has been discussed for several LBPs based on studies that used various biophysical techniques. The present work focuses on two very different LBPs, heart‐type fatty acid binding protein (H‐FABP) and ileal lipid binding protein (ILBP). Using high‐resolution nuclear magnetic resonance spectroscopy, certain resonances belonging to side‐chain protons that are located inside the water‐filled lipid binding cavity were observed. In the case of H‐FABP, the pH‐ and temperature‐dependent behavior of selected side‐chain resonances (Ser82 OgH and the imidazole ring protons of His93) indicated an unusually slow exchange with the solvent, implying that the intricate hydrogen‐bonding network of amino‐acid side‐chains and water molecules in the protein interior is very rigid. In addition, holo H‐FABP appeared to display a reversible self‐aggregation at physiological pH. For ILBP, on the other hand, a more solvent‐accessible protein cavity was deduced based on the pH titration behavior of its histidine residues. Comparison with data from other LBPs implies that the evolutionary specialization of LBPs for certain ligand types was not only because of mutations of residues directly involved in ligand binding but also to a refinement of the internal water scaffold.
Characterization of an Enteropathogenic Bovine Calicivirus Representing a Potentially New Calicivirus Genus
Authors: Smiley J. R. , Chang K. O. , Hayes J. , Vinjé J. , Saif L. J. 
Published: September 2002

ABSTRACTBovine enteric caliciviruses (BEC) are associated with diarrhea in young calves. The BEC strains detected in Europe form a third genogroup within the genus “Norwalk-like viruses” (NLV) of the familyCaliciviridae. In this report, we present sequence, clinical, and histological data characterizing a novel enteropathogenic BEC strain, NB, detected in fecal specimens from calves in the United States. The complete RNA genome of the NB virus is 7,453 bases long and is organized into two open reading frames (ORFs). ORF-1 is 2,210 amino acids long and encodes a large nonstructural polyprotein contiguous with the major capsid protein (VP1), similar to the lagoviruses and “Sapporo-like viruses” (SLV). The conserved calicivirus motifs were identified in the nonstructural proteins. ORF-2 is located at the 3′ end of the genome and encodes a small basic protein (VP2) of 225 amino acids. The 5′ and 3′ untranslated regions are 74 and 67 bases long, respectively. Among caliciviruses, NB virus shows amino acid identities of 14.1 to 22.6% over the entire ORF-1 nonstructural-protein sequence with NLV, SLV, vesivirus, and lagovirus strains, while the overall sequence identity of the complete NB VP-1 with other caliciviruses is low, varying between 14.6 and 26.7%. Phylogenetic analysis of the complete VP1 protein, including strains from all four calicivirus genera, showed the closest grouping of NB virus to be with viruses in the genusLagovirus, which cause liver infections and systemic hemorrhage in rabbits. In gnotobiotic calves, however, NB virus elicited only diarrhea and intestinal lesions that were most severe in the upper small intestine (duodenum and jejunum), similar to the NLV BEC strains. The tissues of major organs, including the lung, liver, kidney, and spleen, had no visible microscopic lesions.
Nonspecific Nucleoside Triphosphatase P4 of Double-Stranded RNA Bacteriophage φ6 Is Required for Single-Stranded RNA Packaging and Transcription
Authors: Pirttimaa Markus J. , Paatero Anja O. , Frilander Mikko J. , Bamford Dennis H. 
Published: September 2002

ABSTRACT
Bacteriophage φ6 has a segmented double-stranded RNA genome. The genomic single-stranded RNA (ssRNA) precursors are packaged into a preformed protein capsid, the polymerase complex, composed of viral proteins P1, P2, P4, and P7. Packaging of the genomic precursors is an energy-dependent process requiring nucleoside triphosphates. Protein P4, a nonspecific nucleoside triphosphatase, has previously been suggested to be the prime candidate for the viral packaging engine, based on its location at the vertices of the viral capsid and its biochemical characteristics. In this study we were able to obtain stable polymerase complex particles that are completely devoid of P4. Such particles were not able to package ssRNA segments and did not display RNA polymerase (either minus- or plus-strand synthesis) activity. Surprisingly, a mutation in P4, S250Q, which reduced the level of P4 in the particles to about 10% of the wild-type level, did not affect RNA packaging activity or change the kinetics of packaging. Moreover, such particles displayed minus-strand synthesis activity. However, no plus-strand synthesis was observed, suggesting that P4 has a role in the plus-strand synthesis reaction also.
Vesicular Stomatitis Virus Infection Alters the eIF4F Translation Initiation Complex and Causes Dephosphorylation of the eIF4E Binding Protein 4E-BP1
Authors: Connor John H. , Lyles Douglas S. 
Published: September 2002

ABSTRACTVesicular stomatitis virus (VSV) modulates protein synthesis in infected cells in a way that allows the translation of its own 5′-capped mRNA but inhibits the translation of host mRNA. Previous data have shown that inactivation of eIF2α is important for VSV-induced inhibition of host protein synthesis. We tested whether there is a role for eIF4F in this inhibition. The multisubunit eIF4F complex is involved in the regulation of protein synthesis via phosphorylation of cap-binding protein eIF4E, a subunit of eIF4F. Translation of host mRNA is significantly reduced under conditions in which eIF4E is dephosphorylated. To determine whether VSV infection alters the eIF4F complex, we analyzed eIF4E phosphorylation and the association of eIF4E with other translation initiation factors, such as eIF4G and the translation inhibitor 4E-BP1. VSV infection of HeLa cells resulted in the dephosphorylation of eIF4E at serine 209 between 3 and 6 h postinfection. This time course corresponded well to that of the inhibition of host protein synthesis induced by VSV infection. Cells infected with a VSV mutant that is delayed in the ability to inhibit host protein synthesis were also delayed in dephosphorylation of eIF4E. In addition to decreasing eIF4E phosphorylation, VSV infection also resulted in the dephosphorylation and activation of eIF4E-binding protein 4E-BP1 between 3 and 6 h postinfection. Analysis of cap-binding complexes showed that VSV infection reduced the association of eIF4E with the eIF4G scaffolding subunit at the same time as its association with 4E-BP1 increased and that these time courses correlated with the dephosphorylation of eIF4E. These changes in the eIF4F complex occurred over the same time period as the onset of viral protein synthesis, suggesting that activation of 4E-BP1 does not inhibit translation of viral mRNAs. In support of this idea, VSV protein synthesis was not affected by the presence of rapamycin, a drug that blocks 4E-BP1 phosphorylation. These data show that VSV infection results in modifications of the eIF4F complex that are correlated with the inhibition of host protein synthesis and that translation of VSV mRNAs occurs despite lowered concentrations of the active cap-binding eIF4F complex. This is the first noted modification of both eIF4E and 4E-BP1 phosphorylation levels among viruses that produce capped mRNA for protein translation.