bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid activation of Mac‐1(CD11b/CD18) molecules on macrophages by a new chemotactic factor ‘Gasserokine’ produced by Lactobacillus gasseri JCM1131T
Authors: KITAZAWA Haruki , INO Tomohiko , KAWAI Yasushi , ITOH Takatoshi , SAITO Tadao 
Published: March 2003

ABSTRACTThe chemoattractant activity of a new chemotactic factor, ‘Gasserokine’ produced by Lactobacillus gasseri JCM1131T, has been proposed as a novel immunological function of probiotic lactic acid bacteria. The focus of the present study was to understand the mechanism of the chemotaxis induced by Gasserokine, using activation of an adhesion molecule, Mac‐1 (CD11b/CD18) on macrophages. The macrophage chemotaxis to Gasserokine was abolished by preincubation of macrophages with the anti‐Mac‐1 mAb. Gasserokine induced rapid serine phosphorylation of CD18 molecules within 1 min of stimulation, but the effect was short‐lived. Substantial tyrosine phosphorylation was observed in CD18‐associated protein of macrophages stimulated by Gasserokine. The tyrosine phosphorylation was confirmed in macrophages stimulated with Gasserokine and also serine/threonine phosphorylation was detected on CD18 molecules by laser microscopy using a double immunostaining method. These results suggest that selective activation of intracellular signaling cascades, such as the mitogen‐activated protein kinase pathway, are related to the macrophage chemotaxis induced by Gasserokine.
Molecular sexing of Japanese cormorants used for traditional fishing on the Nagara River in Gifu City
Authors: INOUE‐MURAYAMA Miho , UEDA Yuko , YAMASHITA Tetsuji , NISHIDA‐UMEHARA Chizuko , MATSUDA Yoichi , MASEGI Toshiaki , ITO Shin’ichi 
Published: March 2003

ABSTRACTThe Japanese cormorants used in traditional fishing in Japan are wild derived and their sex cannot be determined from their appearance. Applicability of molecular sex determination based on the size difference between CHD1Z and CHD1W introns was confirmed in male and female Japanese cormorants whose sexes had been ascertained by pathological autopsy. All of 21 birds of unknown sex reared by a cormorant fishing master were identified as males. The molecular sexing method will provide valuable information on sex differences of wild Japanese cormorants, including tameness, trainability, behavior and fishing capability, as well as for future trials involving artificial reproduction.
Effects of medium‐chain fatty acid‐cyclodextrin complexes on ruminal methane production in vitro
Authors: AJISAKA Noriko , MOHAMMED Nazimuddin , HARA Koji , MIKUNI Katsuhiko , HARA Kozo , HASHIMOTO Hitoshi , KUMATA Takako , KANDA Shuhei , ITABASHI Hisao 
Published: March 2003

ABSTRACTThe purpose of the present study was to evaluate effects of medium‐chain fatty acid‐cyclodextrin (CD) complexes on ruminal methane and volatile fatty acid production, and protozoal activity in vitro. Medium‐chain fatty acid‐CDs used in this study were caprylic acid (C8)‐αCD or ‐βCD, capric acid (C10)‐αCD or ‐βCD, and lauric acid (C12)‐αCD or ‐βCD. A 60‐mL of diluted rumen fluid was incubated anaerobically at 38°C for 6 h with the addition of the complex (10–40 mg as fatty acid). Each of the fatty acid‐CDs reduced the number of protozoa, with the order C10 > C12 > C8, and βCD complexes were more effective than αCD complexes. Molar proportions of acetic acid remained unchanged with the addition of fatty acid‐CD, while that of propionic acid increased, being significant for C8‐αCD and βCD, and C10‐αCD and βCD (P < 0.05). Hydrogen production decreased by about 70% of control with the addition of 40 mg of C8 and C10‐CD, on the other hand, it tended to increase with the addition of C12‐CD in both αCD and βCD. Methane production decreased by about 20% with the addition of 40 mg of complexes, except for C10‐βCD, which significantly reduced methane production by about 60%. In conclusion, the addition of C8 or C10‐CD to ruminant diets may be effective in reducing methane production.
Effects of intracerebroventricular infusions of corticotropin‐releasing hormone in sheep
Authors: YAYOU Ken‐ichi , OTANI Humihiro , TAKUSARI Naozumi , UETAKE Katsuji , OKAMOTO Takashi 
Published: March 2003

ABSTRACTTo provide new insights into the neural mechanisms of physiological and behavioral responses to stressors in sheep, acute changes in endocrine, autonomic and behavioral functions following 30 min infusions of ovine‐corticotropin‐releasing hormone (oCRH; 0, 0.5, 5 or 50 µg/0.5 mL of artificial cerebrospinal fluid/30 min) into the third ventricle of sheep (n = 7–8) were examined. Serial blood samples were collected through indwelling jugular catheters to determine plasma cortisol concentrations (CORT). Heart rate (HR) and rectal temperature (RT) were obtained via telemetry systems. The behaviors of the animal were monitored simultaneously. Intracerebroventricular infusions of CRH dose‐dependently induced an increase in CORT; there was a time–treatment interaction in CORT (P < 0.001). There was not a time–treatment interaction either in HR (P = 0.29) or in RT (P = 0.28). That RT showed a tendency to decrease with higher doses of CRH in sheep was in contradiction to previous reports in rats and pigs. As to changes in behavioral function, only the induction of bleating was marked. These results suggest that in physiological and behavioral responses of sheep to stressors, CRH regulates the increase in CORT and the induction of bleating. However, CRH might have little function in sympathetic nervous activation during physiological responses to stressors in sheep.
Lateritic and redoximorphic features in a faulted landscape near Manaus, Brazil
Authors: Fritsch E. , Montes‐Lauar C. R. , Boulet R. , Melfi A. J. , Balan E. , Magat P. 
Published: March 2003

SummaryThe soils and sediments of the uplands in the Manaus region are described and analysed along a representative cross‐section. There are two broad types of features, lateritic and redoximorphic. Their formation is linked to two main processes acting under contrasted hydrological regimes. The first process, acting under well‐drained conditions, is lateritization. It has transformed strongly weathered sediment into soil and led to depletion of silica (mainly quartz) as well as to relative accumulation of both kaolinite and iron oxides (haematite and goethite). Crystallographic changes observed in the latter have resulted from alternating dissolution and crystallization cycles without significant transfer of iron and alumina. However, in the uppermost soil, dissolution of kaolinite has prevailed over crystallization, leading to depletion of clay and the formation of tiny crystals of gibbsite disseminated throughout the groundmass. The second process results from the development of reducing conditions in groundwater giving redoximorphic features in lateritic soils and sediments. In the sediments, iron has been depleted by regional aquifers to form a pallid zone. In the soil, large amounts of iron and minor amounts of alumina, mainly from aluminous goethite, have been mobilized at first in small patches, which with further mobilization and vertical transfer of these elements have increased in size and have led to the formation of bleached horizons over thin iron pans. Iron has crystallized predominantly as haematite in the iron pans and alumina as large crystals of gibbsite in soil voids. Formation of impervious iron pans holds up fluctuating perched groundwater in the overlying horizons depending on rainfall events.Neotectonic events (formation of uplifted blocks and small grabens) have markedly altered the hydrological regimes. In the uplifted blocks, the soil has been deeply truncated and iron loss has been checked in the uppermost sediment. By contrast, mobilization of iron has been initiated at various places in the soil of the small grabens. In this way tectonic events have checked mobilization of iron in sediments but activated it in soils, leaving spectacular fingerprints on the landscape.
Gas exchange and photosynthetic acclimation over subambient to elevated CO2 in a C3–C4 grassland
Authors: Anderson Laurel J. , Maherali Hafiz , Johnson Hyrum B. , Polley H. Wayne , Jackson Robert B. 
Published: March 2003

AbstractAtmospheric CO2 (Ca) has risen dramatically since preglacial times and is projected to double in the next century. As part of a 4‐year study, we examined leaf gas exchange and photosynthetic acclimation in C3 and C4 plants using unique chambers that maintained a continuous Ca gradient from 200 to 550 µmol mol−1 in a natural grassland. Our goals were to characterize linear, nonlinear and threshold responses to increasing Ca from past to future Ca levels. Photosynthesis (A), stomatal conductance (gs), leaf water‐use efficiency (A/gs) and leaf N content were measured in three common species: Bothriochloa ischaemum, a C4 perennial grass, Bromus japonicus, a C3 annual grass, and Solanum dimidiatum, a C3 perennial forb. Assimilation responses to internal CO2 concentrations (A/Ci curves) and photosynthetically active radiation (A/PAR curves) were also assessed, and acclimation parameters estimated from these data. Photosynthesis increased linearly with Ca in all species (P < 0.05). S. dimidiatum and B. ischaemum had greater carboxylation rates for Rubisco and PEP carboxylase, respectively, at subambient than superambient Ca (P < 0.05). To our knowledge, this is the first published evidence of A up‐regulation at subambient Ca in the field. No species showed down‐regulation at superambient Ca. Stomatal conductance generally showed curvilinear decreases with Ca in the perennial species (P < 0.05), with steeper declines over subambient Ca than superambient, suggesting that plant water relations have already changed significantly with past Ca increases. Resource‐use efficiency (A/gs and A/leaf N) in all species increased linearly with Ca. As both C3 and C4 plants had significant responses in A, gs, A/gs and A/leaf N to Ca enrichment, future Ca increases in this grassland may not favour C3 species as much as originally thought. Non‐linear responses and acclimation to low Ca should be incorporated into mechanistic models to better predict the effects of past and present rising Ca on grassland ecosystems.
The impact of sampling frequency and sampling times on chamber‐based measurements of N2O emissions from fertilized soils
Authors: Smith Keith A. , Dobbie Karen E. 
Published: March 2003

AbstractAn automated closed‐chamber system was developed to measure N2O fluxes in the field. It was deployed at two N‐fertilized grassland sites in two successive years, together with replicated manual chambers, to investigate the spatial and temporal variability in fluxes, and the likely impact of sampling frequency on cumulative flux values. The automated system provided flux data at 8‐h intervals, while manual sampling was conducted at intervals of 3–7 days. The autochambers showed fluctuations in emissions not detected by manual sampling. However, integrated flux values based on the more intensive measurements were on average no more than 14% greater than those based on data from the autochambers that were obtained at the same time as manual sampling. This difference was not significant and well within the spatial variability determined with manual chambers. If daily sampling intervals were used immediately after fertilization, the agreement was closer still, increasing the confidence that can be placed in manual procedures. Diurnal variations in temperature and flux were small, and results from sampling at mid‐day were not significantly different from those based on early morning or evening sampling. Where diurnal fluctuations in temperature and flux are likely to be much larger, the autochamber/sampler system could prove very useful to quantify the effect.
Growth enhancement due to global atmospheric change as predicted by terrestrial ecosystem models: consistent with US forest inventory data
Authors: Joos Fortunat , Prentice I. Colin , House Joanna I. 
Published: March 2003

AbstractSmall reported growth enhancement factors based on analyses of forest inventory data from the eastern USA (Caspersen et al. 2000, Science, 290, 1148–1151) have been interpreted as evidence against CO2 fertilization in natural forests. We show to the contrary that growth enhancement in response to rising CO2, as found in ecosystems with experimental CO2 enrichment and implemented in terrestrial ecosystem models, is consistent with the data that have been presented within their uncertainties. Comparing forest inventory data with results of an empirical model of age‐dependent biomass accumulation, we find that growth enhancement of plausible magnitude could not be detected in these data, even if it were present. Although forest regrowth due to land‐use change is recognized as an important cause of carbon uptake by eastern US forests, forest inventory data do not provide a basis for eliminating environmentally induced growth enhancement as a substantial contribution to the global terrestrial carbon sink.
Replication fork block protein, Fob1, acts as an rDNA region specific recombinator in S. cerevisiae
Authors: Johzuka Katsuki , Horiuchi Takashi 
Published: March 2003

AbstractBackground: The analysis of homologous recombination in the tandemly repeating rDNA array of Saccharomyces cerevisiae should provide useful information about the stability of not only the rDNA repeat but also the abundant repeated sequences on higher eukaryotic genomes. However, the data obtained so far are not yet conclusive, due to the absence of a reliable assay for detecting products of recombination in the rDNA array.Results: We developed an assay method to detect the products of unequal sister‐chromatid recombination (marker‐duplication products) in yeast rDNA. This assay, together with the circular rDNA detection assay, was used for the analysis. Marker‐duplication occurred throughout the rDNA cluster, preferentially between nearby repeat units. The FOB1 and RAD52 genes were required for both types of recombinant formation. FOB1 showed a gene dosage effect on not only the amounts of both recombinants, but also on the copy number of the repeat. However, unlike the RAD52 gene, the FOB1 gene was not involved in homologous recombination in a non‐rDNA locus. In addition, the marker‐duplication products were drastically decreased in the mre11 mutant.Conclusion: Our data demonstrate that FOB1‐ and RAD52‐dependent homologous recombination cause the gain and loss of a few copies of the rDNA unit, and this must be a basic mechanism responsible for amplification and reduction of the rDNA copy number. In addition, FOB1 may also play a role in the copy number regulation of rDNA tandem repeats.
Meu10 is required for spore wall maturation in Schizosaccharomyces pombe
Authors: Tougan Takahiro , Chiba Yasuyoshi , Kakihara Yoshito , Hirata Aiko , Nojima Hiroshi 
Published: March 2003

AbstractBackground: Many genes are meiosis and/or sporulation‐specifically transcribed during this process. Isolation and analysis of these genes might help us to understand how meiosis and sporulation are regulated. For this purpose, we have isolated a large number of cDNA clones from Schizosaccharomyces pombe whose expression is up‐regulated during meiosis.Results: We have isolated meu10+ gene, which encodes 416 amino acids and bears homology to SPS2 of Saccharomyces cerevisiae. A strain whose meu10+ gene has been deleted forms no viable spores. Thin‐section electron micrographs showed that the meu10Δ strain has abnormally formed spore walls, and then they disrupt, allowing cytoplasmic material to escape. The Meu10‐GFP fusion protein is localized to the spore periphery, thereafter returned to the cytoplasm after sporulation. Meu10‐GFP localization to the spore wall was almost normal in the bgs2Δ or chs1Δ mutants that lack 1,3‐β‐glucan or chitin, respectively. In contrast, 1,3‐β‐glucan is abnormally localized in meu10Δ cells. Meu10 has an N‐terminal domain with homology to the mammalian insulin receptor and a C‐terminal domain with a transmembrane motif. Mutants whose N‐terminal or C‐terminal domain was truncated were severely defective for sporulation.Conclusions: Meu10 is a spore wall component and plays a pivotal role in the formation of the mature spore wall structure.
Effects of paternal drinking, conduct disorder and childhood home environment on the development of alcohol use disorders in a Thai population
Authors: Assanangkornchai Sawitri , Geater Alan F. , Saunders John B. , McNeil Donald R. 
Published: March 2003

ABSTRACTAimsTo identify influences on the development of alcohol use disorders in a Thai population, particularly parental drinking and childhood environment.DesignCase–control study.SettingA university hospital, a regional hospital and a community hospital in southern Thailand.ParticipantsNinety‐one alcohol‐dependents and 77 hazardous/harmful drinkers were recruited as cases and 144 non‐ or infrequent drinkers as controls.MeasurementsData on parental drinking, family demographic characteristics, family activities, parental disciplinary practice, early religious life and conduct disorder were obtained using a structured interview questionnaire. The main outcome measure was the subject's classification as alcohol‐dependent, hazardous/harmful drinker or non‐/infrequent drinker.FindingsA significant relationship was found between having a drinking father and the occurrence of hazardous/harmful drinking or alcohol dependence in the subjects. Childhood factors (conduct disorder and having been a temple boy, relative probability ratios, RPRs and 95% CI: 6.39, 2.81–14.55 and 2.21, 1.19–4.08, respectively) also significantly predicted alcohol dependence, while perceived poverty and ethnic alienation was reported less frequently by hazardous/harmful drinkers and alcohol‐dependents (RPRs and 95% CIs = 0.34, 0.19–0.62 and 0.59, 0.38–0.93, respectively) than the controls. The relative probability ratio for the effect of the father's infrequent drinking on the son's alcohol dependence was 2.92 (95% CI = 1.42–6.02) and for the father's heavy or dependent drinking 2.84 (95% CI = 1.31–6.15).ConclusionsBeing exposed to a light‐drinking father increases the risk of a son's alcohol use disorders exhibited either as hazardous–harmful or dependent drinking. However, exposure to a heavy‐ or dependent‐drinking father is associated more uniquely with an increased risk of his son being alcohol‐dependent. The extent to which this is seen in other cultures is worthy of exploration.
Receptor potential characteristics during direct stereocilia stimulation of isolated outer hair cells from the guinea‐pig
Authors: SHVAREV  , CANLON  
Published: March 2003

The receptor potential as a function of stimulus amplitude and frequency was studied with the patch‐clamp technique in isolated outer hair cells (OHCs) with a length ranging from 30 to 87 μm during direct mechanical stimulation of the stereocilia. The amplitude and frequency of the stimulation were varied from 125 nm to 2 μm and from 100 Hz to 2.5 kHz, respectively. The mean resting membrane potential before stimulation was −64.25 ± 1.4 mV (mean ± SE, n = 26). Irrespective of the frequency used, stereocilia stimulation produced a combination of AC and DC responses, and both components showed saturation with increasing stimulation. Frequency responses appeared to be a function of intensity and resembled a low‐pass filter with a time constant ranging from 0.2 to 2.0 ms. With increasing stereocilia stimulation, the relative contribution of high frequencies to the AC component decreased, suggesting a decrease of the corner frequency. The saturated amplitude of the AC component for low‐frequency stimulation (100 Hz) was proportional to cell length and increased with a mean rate of 0.014 mV μm−1.A relationship between the DC response of the receptor potential and the pre‐stimulus membrane potential was found. Recordings with more negative membrane potentials had greater DC components, while more depolarized recordings demonstrated smaller DC components. These fluctuations seemed to be defined by the interaction between the probe and stereocilia bundle and could be in the range of the transfer function for each cell.
The relationship of natural killer cell counts, perforin mRNA and CD2 expression to post‐exercise natural killer cell activity in humans
Authors: MILES M. P. , MACKINNON L. T. , GROVE D. S. , WILLIAMS N. I. , BUSH J. A. , MARX J. O. , KRAEMER W. J. , MASTRO A. M. 
Published: March 2003

ABSTRACTThe aim of this study was to further investigate the mechanism of suppression of natural killer (NK) cell cytotoxic activity in peripheral blood following strenuous exercise. Blood was collected for analysis of NK cell concentration, cytotoxic activity, CD2 surface expression and perforin gene expression from runners (RUN, n=6) and resting controls (CONTROL, n=4) pre‐exercise, 0, 1.5, 5, and 24 h following a 60‐min treadmill run at 80% of VO2 peak. Natural killer cytotoxic activity, measured using a whole blood chromium release assay, fluctuated minimally in the CONTROL group and increased by 63% and decreased by 43% 0 and 1.5 h post‐exercise, respectively, in the RUN group (group × time, P < 0.001). Lytic index (cytotoxic activity per cell) did not change. Perforin mRNA, measured using quantitative real‐time polymerase chain reaction (QRT–PCR) decreased from pre‐ to post‐exercise and remained decreased through 24 h. The decrease from pre‐ to 0 h post‐exercise was seen predominately in the RUN group and was inversely correlated (r=– 0.95) to pre‐exercise perforin mRNA. The NK cell surface expression of CD2 (lymphocyte function‐associated antigen‐2) was determined using fluorescent antibodies and flow cytometry. There was no change in the proportion of NK cells expressing CD2 or CD2 density. We conclude that (1) numerical redistribution accounted for most of the change in NK cytotoxic activity following a strenuous run, (2) decrease in perforin gene expression during the run was inversely related to pre‐exercise levels but did not parallel changes in cytotoxic activity, and (3) CD2 surface expression was not affected by exercise.
Analysis of the tubuloglomerular feedback mechanism in renal autoregulation
Authors: KIIL F. 
Published: March 2003

ABSTRACTAlong the juxtaglomerular segment of the afferent arteriole the luminal pressure p approaches the glomerular capillary pressure of 55–60 mmHg. At such low luminal pressures the myogenic mechanism contracts only if extravascular pressure pex is subatmospheric. According to Poiseuille's formula complete autoregulation requires that blood flow is F=5Kr04/Δx at arterial pressures exceeding 65 mmHg; r0 is the radius of the relaxed segment at transmural pressure p – pex ≤ 60 mmHg, where pex is the extravascular pressure; Δx is the length of the main preglomerular segment, 10 times longer than the juxtaglomerular segment. Consistent with in vitro studies a myogenic mechanism may reduce the relaxed juxtaglomerular radius rjx=0.7r0 by 40% at a transmural pressure of 140 mmHg. Fifty and 60% reductions are also considered. Integration of Poiseuille's formula shows that complete autoregulation of preglomerular blood flow requires negative extravascular pressures pex=–90 to –55 mmHg dependent on contractile force. Negative pressure of this magnitude is generated by effective hyperosmolality <5 mOsm across the membrane separating cleft from pole cushion. Negative pressure stays constant at arterial pressures exceeding 90–110 mmHg, implying constant tubuloglomerular feedback, but approaches atmospheric pressure at lower arterial pressure, suggesting maintenance of blood flow by reduction in the glomerular filtration rate; a rise in macula densa concentrations [NaCl]md by 0.15 mM or [NaHCO3]md by 2 mM raises extravascular pressure towards atmospheric levels by ≈40 mmHg. A 40‐mmHg rise in interstitial pressure exerts the same effect. Loop diuretics nullify osmotic force and dilate juxtaglomerular and main segments by raising juxtaglomerular extravascular pressure towards atmospheric levels.