bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence, isolation, and partial sequence analysis of hepatitis E virus from domestic animals in China
Authors: Wang You‐Chun , Zhang Hua‐yuan , Xia Ning‐shao , Peng Geng , Lan Hai‐Yun , Zhuang Hui , Zhu Yong‐Hong , Li Shao‐Wei , Tian Ke‐Gong , Gu Wen‐Jie , Lin Jing‐Xiang , Wu Xing , Li He‐Min , Harrison Tim J.
Published: September 2002

Evidence that hepatitis E is zoonotic is accumulating. Serum samples were collected from pigs, cattle, and goats from various regions of China to determine whether they had been infected with hepatitis E virus (HEV). An in‐house enzyme immunoassay (EIA) and reverse transcriptase‐polymerase chain reaction (RT‐PCR) with primers from open reading frame (ORF) 2 were used to detect anti‐HEV antibodies and HEV RNA. The mean positivity rates of anti‐HEV antibody for pigs and cattle were 78.8% and 6.3% but none of the goat sera were positive. Pigs may be more susceptible to infection with HEV than cattle or goats. Five of 263 pig sera were positive for HEV RNA and four of these five were also positive for anti‐HEV. The PCR products (nt 6007–6354) were cloned and sequenced and compared to other HEV sequences in the nucleotide databases. The five sequences shared 83–93% identity to each other at the nucleotide level and 74–79%, 73–74%, 73–78%, and 83–99% identity to HEV genotypes 1, 2, 3, and 4, respectively. They were closely related to human isolates of HEV genotype 4. Phylogenetic analyses also place these swine sequences in HEV genotype 4, resembling most closely viruses isolated from Chinese patients with acute hepatitis. These data support the hypothesis that sporadic hepatitis E in China is zoonotic. J. Med. Virol. 67:516–521, 2002. © 2002 Wiley‐Liss, Inc.
HHV‐6 infects human aortic and heart microvascular endothelial cells, increasing their ability to secrete proinflammatory chemokines
Authors: Caruso Arnaldo , Rotola Antonella , Comar Manola , Favilli Flavia , Galvan Monica , Tosetti Maria , Campello Cesare , Caselli Elisabetta , Alessandri Giulio , Grassi Manuela , Garrafa Emirena , Cassai Enzo , Di Luca Dario
Published: September 2002

Endothelial cells are important targets for herpesvirus infection. To evaluate the biological effects of human herpesvirus‐6 (HHV‐6) infection, adult heart microvascular and aortic endothelial cells were examined for in vitro susceptibility to HHV‐6 and for the alterations induced by viral infection on the production of monocyte chemoattractant protein‐1 (MCP‐1) and interleukin‐8 (IL‐8). Analysis by reverse transcription‐polymerase chain reaction and by in situ polymerase chain reaction showed that HHV‐6 replicates in endothelium in the absence of cytopathic effects, and that viral sequences were present in 20% umbilical vein and in 10% aortic and 1% microvascular endothelium. HHV‐6 infection upregulated the production of MCP‐1 and IL‐8, with differences observed between aortic and microvascular endothelium. These findings demonstrate that endothelial cells represent a potential reservoir for HHV‐6 infection, and the altered pattern of chemokine production can lead to attraction of immunocompetent cells and to the development of inflammatory processes. J. Med. Virol. 67:528–533, 2002. © 2002 Wiley‐Liss, Inc.
Neuroinvasion during delayed primary HHV‐7 infection in an immunocompetent adult with encephalitis and flaccid paralysis
Authors: Ward K.N. , Kalima P. , MacLeod K.M. , Riordan T.
Published: September 2002

Antibody avidity tests have been used to detect primary human herpesvirus‐7 (HHV‐7) infection in an immunocompetent 19‐year‐old man with encephalitis and flaccid paralysis for which all other suspected causes had been excluded. The finding of the viral DNA in the cerebrospinal fluid (CSF) but not in serum samples suggests that primary HHV‐7 infection with invasion of the central nervous system and consequential disease had occurred. As almost all adults are infected with HHV‐7 in early childhood, the present case of delayed primary infection with serious symptoms must be exceptionally rare and no cases of such late acquisition of the virus have been documented in the literature. This report of HHV‐7 DNA in the CSF of an immunocompetent adult is also unique. J. Med. Virol. 67:538–541, 2002. © 2002 Wiley‐Liss, Inc.
Impaired fibrinolysis in the pathogenesis of dengue hemorrhagic fever
Authors: van Gorp Eric C.M. , Setiati Tatty E. , Mairuhu Albert T.A. , Suharti Catharina , Cate Hugo ten , Dolmans Wil M.V. , van der Meer Jos W.M. , Hack C. Erik , Brandjes Dees P.M.
Published: September 2002

The mechanisms contributing to bleeding complications in dengue hemorrhagic fever were studied by investigating the pattern of activation of the coagulation and fibrinolytic systems in 50 children with severe dengue hemorrhagic fever. Thirteen patients (26%) died, and activation of coagulation was most pronounced in the deceased group. Fibrinolysis was also activated, but this activation was relatively weak compared with that of coagulation as a result of persistently high plasminogen activator inhibitor levels. Plasminogen activator inhibitor also prevented a switch from the procoagulant to the profibrinolytic state in lethal dengue hemorrhagic fever, which was further enhanced by an acquired protein C deficiency. The present study is the first to demonstrate such a mechanism in a viral infection. This imbalance between coagulation and fibrinolysis may be used as a prognostic marker, but it may also be a target for future therapeutic intervention. J. Med. Virol. 67:549–554, 2002. © 2002 Wiley‐Liss, Inc.
Foodborne outbreak caused by a Norwalk‐like virus in India
Authors: Girish R. , Broor S. , Dar L. , Ghosh D.
Published: September 2002

An outbreak of acute gastroenteritis occurred in the nurses' hostel of a civil hospital in Delhi, after a farewell party involving 130 nurses and some of the housekeeping staff. All affected persons had eaten salad sandwiches at the party. Stool samples were collected from six of these patients on the second day of infection. All six samples, when tested for the presence of common bacteria, parasites, and rotavirus, were found to be negative. The clinical features of this outbreak matched the criteria set for outbreaks caused by Norwalk‐like viruses (NLVs). Reverse transcription‐polymerase chain reaction (RT‐PCR) was carried out on these six samples, using primers from the RNA‐dependent RNA polymerase (RdRp) gene of NLVs. Immunoelectron microscopy was carried out on two of the samples, using convalescent phase serum. All six samples were positive for genogroup (GG) II NLVs by RT‐nested PCR. Aggregates of 32‐nm viral particles were visualized by immunoelectron microscopy in one of the two samples. Sequencing of the RdRp gene was done on amplicons from three samples; phylogenetic analysis placed the isolates NDV/1999 in a Toronto virus cluster of GG II NLVs. This is the first report of a food‐borne outbreak attributable to NLVs from India. J. Med. Virol. 67:603–607, 2002. © 2002 Wiley‐Liss, Inc.
Circulation of the novel G9 and G8 rotavirus strains in Nigeria in 1998/1999
Authors: Steele A.D. , Nimzing L. , Peenze I. , de Beer M.C. , Geyer A. , Angyo I. , Gomwalk N.E.
Published: September 2002

An epidemiological survey investigating the prevalence of rotavirus infection in infants and young children with acute diarrhoea was undertaken in Jos State, Nigeria, between January 1998 and April 1999. In total, 672 faecal specimens were collected from children aged between 1 and 60 months with acute infantile gastroenteritis. The 10–20% stool suspensions were examined by an ELISA for the presence of group A rotavirus antigen (Rotavirus IDEIA, Dako, UK). Only 116 specimens (17.3%) were positive for the group A rotavirus antigen detected by this ELISA. The rotavirus‐positive specimens were analysed with monoclonal antibodies specific for rotavirus VP6 subgroup I and II, and for VP7 serotypes G1–G4, G8, and G9. Of the rotavirus strains that could be subgrouped, VP6 subgroup I and II strains circulated at similar levels. Amongst the strains that could be serotyped, VP7 G9 strains predominated occurring in 17 cases, with G3 (n = 10) and G1 (n = 9) strains occurring in lower numbers. Four G8 strains were detected and only one G2 and no G4 strains were identified. This report extends the description of the global distribution of G9 rotavirus strains. J. Med. Virol. 67:608–612, 2002. © 2002 Wiley‐Liss, Inc.
Time domain global modelling of EM propagation in semiconductor using irregular grids
Authors: Tsai Hsiao‐Ping , Coccioli Roberto , Itoh Tatsuo
Published: September 2002

A two‐dimensional finite volume time domain (FVTD) method using a triangular grid is applied to the analysis of electromagnetic wave propagation in a semiconductor. Maxwell's equations form the basis of all electromagnetic phenomena in semiconductors and the drift‐diffusion model is employed to simulate charge transport phenomena in the semiconductor. The FVTD technique is employed to solve Maxwell's equations on an irregular grid and the finite box method is implemented on the same grid to solve the drift‐diffusion model for carrier concentration. The locations of unknowns have been chosen to allow linking coupled Maxwell's equations and transport equations in a seamless way. To achieve suitable accuracy and computational efficiency, using irregular grid topology allows a finer mesh in doped region and at junction, and a coarser mesh in substrate and insulting regions. The proposed scheme has been implemented and verified by characterizing electromagnetic wave propagation at microwave frequency in a semiconductor slab with arbitrary doping profile. Copyright © 2002 John Wiley & Sons, Ltd.
Direct isolation of committed neuronal progenitor cells from transgenic mice coexpressing spectrally distinct fluorescent proteins regulated by stage‐specific neural promoters
Authors: Sawamoto Kazunobu , Yamamoto Atsuyo , Kawaguchi Ayano , Yamaguchi Masahiro , Mori Kensaku , Goldman Steven A. , Okano Hideyuki
Published: September 2002

Many tissues arise from pluripotent stem cells through cell‐type specification and maturation. In the bone marrow, primitive stem cells generate all the different types of blood cells via the sequential differentiation of increasingly committed progenitor cells. Cell‐surface markers that clearly distinguish stem cells, restricted progenitors, and differentiated progeny have enabled researchers to isolate these cells and to study the regulatory mechanisms of hematopoiesis. Neuronal differentiation appears to involve similar mechanisms. However, neural progenitor cells that are restricted to a neuronal fate have not been characterized in vivo, because specific cell‐surface markers are not available. We have developed an alternative strategy to identify and isolate neuronal progenitor cells based on dual‐color fluorescent proteins. To identify and isolate directly progenitor cells from brain tissue without the need for either transfection or intervening cell culture, we established lines of transgenic mice bearing fluorescent transgenes regulated by neural promoters. One set of transgenic lines expressed enhanced yellow fluorescent protein (EYFP) in neuronal progenitor cells and neurons under the control of the Tα1 α‐tubulin promoter. Another line expressed enhanced green fluorescent protein (EGFP) in immature neural cells under the control of the enhancer/promoter elements of the nestin gene. By crossing these lines we obtained mice expressing both transgenes. To isolate neuronal progenitor cells directly from the developing brain, we used flow cytometry, selecting cells that expressed EGFP and EYFP simultaneously. We expect this strategy to provide valuable material with which to study the mechanisms of neurogenesis and to develop cell‐based therapies for neurological disorders. J. Neurosci. Res. 65:220–227, 2001. © 2001 Wiley‐Liss, Inc.
Models of brain injury and alterations in synaptic plasticity
Authors: Albensi Benedict C.
Published: September 2002

Animal models are crucial for understanding human pathophysiological processes and for understanding how connections are injured, lost, or even regenerated and/or repaired. When animal models are used in conjunction with theoretical computational models, an ideal combination is achieved that potentially yields insight and encourages the formation of new theories concerning connectionism, cognitive functioning, and synaptic mechanisms. Mechanisms regulating glutamate receptor activation and intracellular calcium levels are important for normal synaptic transmission. These mechanisms (and others) are also critical during and after brain injury when the potential exists for these mechanisms to function pathologically. Interestingly enough, the regulation of glutamate receptor activation and intracellular calcium levels is also involved in normal processes of neuronal and synaptic plasticity. In addition, studies have shown that neurotrophins and cytokines, which are released after brain injury, can be neuroprotective and may also be important in synaptic plasticity. Furthermore, synaptic plasticity is a phenomenon thought by many to be necessary for memory encoding. If this is the case, then research described in this review has significant scientific merit concerning plasticity and memory and clinical benefit for understanding pathophysiologic processes associated with brain injury and memory impairment. This paper reviews the application of experimental animal models of brain injury for simulating conditions of stroke, trauma, and epilepsy (and/or seizure generation) and the associated cellular mechanisms of brain injury. The paper also briefly addresses the advantage of using computational models in combination with experimental models for hypothesis building and for aiding in the interpretation of empirical data. Finally, it reviews studies concerning brain injury and synaptic plasticity. J. Neurosci. Res. 65:279–283, 2001. © 2001 Wiley‐Liss, Inc.
Neurotrophin secretion from cultured microglia
Authors: Nakajima Kazuyuki , Honda Shizuyo , Tohyama Yoko , Imai Yoshinori , Kohsaka Shinichi , Kurihara Tadashi
Published: September 2002

Because microglia have been suggested to produce neurotrophins, we tested this ability in vitro. Rat primary microglia were found to constitutively secrete a limited amount of brain‐derived neurotrophic factor (BDNF), but nerve growth factor (NGF) and neurotrophin‐3 (NT‐3) were undetectable in the conditioned medium. Stimulation of the cells with lipopolysaccharide (LPS) increased BDNF secretion, and induced NGF secretion. As a first step to examine this regulation system, the association of protein kinase C (PKC) was pharmacologically analyzed. A PKC activator, phorbol‐12‐myristate‐13‐acetate, enhanced the secretion of BDNF. Pre‐treatment of microglia with a PKC inhibitor, bisindolylmaleimide, suppressed LPS‐stimulated BDNF secretion as well as the constitutive one. These results suggest that the PKC signaling cascade is closely associated with BDNF secretion. Among PKC isoforms, PKCα probably plays a role in BDNF secretion, based on the results of experiments using a specific PKC activator, 1‐oleoyl‐2‐acetyl‐sn‐glycerol, and a specific PKC inhibitor, Gö 6976, and by immunoblotting. Taken together, these findings suggest that the secretion of BDNF from microglia is regulated through PKCα‐associated signal transduction mechanism. J. Neurosci. Res. 65:322–331, 2001. © 2001 Wiley‐Liss, Inc.
The cross‐level effects of culture and climate in human service teams
Authors: Glisson Charles , James Lawrence R.
Published: September 2002

This two‐level study of child welfare and juvenile justice case management teams addresses construct, measurement, and composition issues that plague multilevel research on organizational culture and climate. Very few empirical studies have examined both culture and climate simultaneously, and none have provided evidence that culture and climate are distinct or similar constructs. Confirmatory factor analysis (CFA), within‐group consistency analysis (rwg), between‐group differences (ICC and eta‐squared), and hierarchical linear models (HLM) analysis provide evidence that climate and culture are separate constructs that vary by organizational unit, and are related to work attitudes, perceptions, and behavior. Findings link team‐level culture and climate to individual‐level job satisfaction and commitment, perceptions of service quality, and turnover. Copyright © 2002 John Wiley & Sons, Ltd.
The need for and meaning of positive organizational behavior
Authors: Luthans Fred
Published: September 2002

This essay draws from the emerging positive psychology movement and the author's recent articles on the need for and meaning of a positive approach to organizational behavior. Specifically, the argument is made that at this time, the OB field needs a proactive, positive approach emphasizing strengths, rather than continuing in the downward spiral of negativity trying to fix weaknesses. However, to avoid the surface positivity represented by the non‐sustainable best‐sellers, the case is made for positive organizational behavior (POB) to take advantage of the OB field's strength of being theory and research driven. Additional criteria for this version of POB are to identify unique, state‐like psychological capacities that can not only be validly measured, but also be open to development and performance management. Confidence, hope, and resiliency are offered as meeting such POB inclusion criteria. The overall intent of the essay is to generate some positive thinking and excitement for the OB field and ‘hopefully’ stimulate some new theory building, research, and effective application. Copyright © 2002 John Wiley & Sons, Ltd.
Impacts of low frequency variability modes on Canadian winter temperature
Authors: Bonsal Barrie R. , Shabbar Amir , Higuchi Kaz
Published: September 2002

The impacts of El Niño–Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), and the North Atlantic Oscillation (NAO) on winter (January–February–March) temperature variability over Canada are analysed for the period 1900–1995. Through linear regression, regional characteristics in the interannual temperature variability explained by these oscillations are firstly identified. Modulation of El Niño and La Niña winter temperature responses by various combinations of the PDO and NAO is then investigated via composite analysis. Results show the NAO as the dominant low frequency variability mode affecting winter temperature, however, the effects are mainly confined to north‐eastern regions of the country. The ENSO and PDO influences are somewhat weaker and occur over western and central Canada. It is determined that the associated winter PDO pattern has a significant modulating effect on ENSO related temperature responses. Impacts are stronger and more spatially coherent during El Niño episodes when positive PDO winters are associated with strong positive temperature anomalies over most of Canada, neutral PDO with weaker anomalies (positive in the west and negative in the east), and negative PDO with strong negative anomalies over western Canada. Analysis also suggests that La Niña and negative PDO combinations are associated with negative temperature anomalies, especially in the far west. Over eastern regions of Canada, El Niño (La Niña) events modulate the typical positive (negative) NAO temperature responses by generally making them warmer (colder). All observed relationships are explained by variations in associated mid‐tropospheric circulation over the north Pacific (i.e. Aleutian low region), and western and central North America. Results from this investigation aid in the understanding of relationships between low frequency oscillations and winter temperature variability over Canada. They also suggest the possibility of improved winter temperature forecasts based on conditions in the tropical and north Pacific, and the north Atlantic. Copyright © 2001 Royal Meteorological Society
Bootstrap confidence intervals for predicted rainfall quantiles
Authors: Dunn Peter K.
Published: September 2002

Rainfall probability charts have been used to quantify the effect of the Southern Oscillation Index (SOI) on rainfall for many years. To better understand the effect of the SOI phases, we discuss forming confidence intervals on the predicted rainfall quantiles using percentile bootstrap methods. Copyright © 2001 Royal Meteorological Society
Intra‐seasonal rainfall characteristics and their importance to the seasonal prediction problem
Authors: Tennant Warren J. , Hewitson Bruce C.
Published: September 2002

Daily station rainfall data in South Africa from 1936 to 1999 are combined into homogeneous rainfall regions using Ward's clustering method. Various rainfall characteristics are calculated for the summer season, defined as December to February. These include seasonal rainfall total, region‐average number of station rain days exceeding 1 and 20 mm, region‐average of periods between rain days at stations >1 and >20 mm, region‐average of wet spell length (sequential days of station rainfall >1 and >20 mm), correlation of daily station rainfall within a region and correlation of seasonal station rainfall anomalies within a region.

Rank‐ordered rainfall characteristic data generally form an s‐shaped curve, and significance testing of discontinuities in these curves suggests that normal rainfall conditions in South Africa consist of a combined middle three quintiles separated from the outer quintiles, rather than the traditional middle tercile.

The relationships between the various rainfall characteristics show that seasons with a high total rainfall generally have a higher number of heavy rain days (>20 mm) and not necessarily an increase in light rain days. The length of the period between rain days has a low correlation to season totals, demonstrating that seasons with a high total rainfall may still contain prolonged dry periods. These additional rainfall characteristics are important to end‐users, and the analysis undertaken here offers a valuable starting point for seeking physical relationships between rainfall characteristics and the general circulation. Preliminary studies show that the vertical mean wind is related to rainfall characteristics in South Africa. Given that general circulation models capture this part of the circulation adequately, seasonal forecasts of rainfall characteristics become plausible. Copyright © 2002 Royal Meteorological Society.
Influence of Eurasian spring snow cover on Asian summer rainfall
Authors: Liu Xiaodong , Yanai Michio
Published: September 2002

The Eurasian snow cover anomaly in spring has been considered as one of the important factors affecting Asian summer monsoon variability. Using the long time series (1922–98) of Eurasian spring (March–April) snow cover (ESSC) reconstructed by Brown (2000. Journal of Climate 13: 2339) and snow cover (1973–98) and depth (1979–87) data from satellite observation, the influences of ESSC on the all‐India monsoon (June–September) rainfall (AIMR) and the summer rainfall over all parts of Asia are examined. It is found that the statistical relation between AIMR and ESSC changes over a multi‐decadal time scale. The negative correlation between them has increased markedly since the mid 1970s. The region where the summer rainfall has the strongest and most stable negative correlation with the preceding ESSC is located in northern Mongolia, south of Lake Baikal. The correlation between the summer rainfall and ESSC increases after the data are treated with a low‐pass filter, showing that the impact of snow cover may be seen more clearly with the removal of the effect of El Niño–southern oscillation. Comparative analyses for contrasting years with excessive and deficient snow cover show that the anomalies of ESSC occur mainly in northwestern Eurasia. In the years of excessive ESSC anomalies, cooling and a cyclonic circulation anomaly in the lower troposphere appear over the northern part of Eurasia, leading to a Rossby‐wave‐train‐like circulation response, then a weakened East Asia summer monsoon and deficient rainfall with an anticyclonic circulation anomaly south of Lake Baikal. Anomalies with opposite signs occur in the years of deficient snow cover. Copyright © 2002 Royal Meteorological Society.
Vegetation and climate during the Weichselian Early Glacial and Pleniglacial in the Niederlausitz, eastern Germany — macrofossil and pollen evidence
Authors: Bos Johanna A. A. , Bohncke Sjoerd J. P. , Kasse Cornelis , Vandenberghe Jef
Published: September 2002

Cryoturbated organic beds and channel fills, intercalated with sandy and gravelly fluvial units, have been studied in an opencast brown‐coal mine near Nochten (Niederlausitz), eastern Germany. The fluvial–aeolian sequence covers parts of the Early, Pleni‐ and Late‐glacial. The detailed chronology is based on 11 radiocarbon and 12 OSL dates, covering the period between ca. 100 kyr and 11 kyr BP. Basal peat deposits are correlated with an Early Weichselian interstadial. During this period boreal forests were present and minimum mean summer temperatures were > 13°C. Early Pleniglacial deposits are absent. The Middle and Late Pleniglacial environments were treeless and different types of tundra vegetation can be recognised. Minimum mean summer temperatures varied between 10 and 15°C. Vegetation and climate is reconstructed in detail for the periods around 34–38 kyr BP and 24–25 kyr BP. Around 34–38 ka, a mixture between a low shrub tundra and a cottongrass tussock–subshrub tundra was present. The botanical and sedimentological data suggest that from the Middle to the Late Pleniglacial, the climate became more continental, aridity and wind strength increased, and the role of a protecting winter snow cover decreased. A sedge–grass–moss tundra dominated around 24 and 25 kyr BP. Copyright © 2001 John Wiley & Sons, Ltd.
A high resolution, multiproxy Late‐glacial record of climate change and intrasystem responses in northwest England
Authors: Jones Richard T. , Marshall Jim D. , Crowley Stephen F. , Bedford Alan , Richardson Nigel , Bloemendal Jan , Oldfield Frank
Published: September 2002

A lacustrine carbonate sequence from Hawes Water, Lancashire, UK, has been studied using stable isotopic, lithological, pollen and mineral magnetic analysis. The data reveal four abrupt climatic oscillations in the Late‐glacial Interstadial leading up to the onset of the Loch Lomond Stadial. The data also point to climatic warming relatively early within the stadial, ca. 12 500 GRIP yr, prior to the onset of the Holocene. The oxygen isotope record is taken as a signature of climate forcing against which the response of the lake‐system can be monitored. By adopting this approach it is revealed that the response of the biological system to the rapid climatic oscillations is non‐linear and primarily a function of the antecedent conditions. A significant end‐Devensian isotopic excursion (A) is matched by only minor changes in the cold‐adapted floras and faunas. During the warmer interstadial, the response of the biological ecosystem (events B–D) is clearly influenced by thresholds: major changes in the catchment vegetation associated with relatively minor oscillations in the isotopic signature. The stratigraphical patterns reveal significant lag effects between the onset of climate deterioration and resulting changes in vegetation. Copyright © 2002 John Wiley & Sons, Ltd.
Isotopic climate record in a Holocene stalagmite from Ursilor Cave (Romania)
Authors: Onac Bogdan Petroniu , Constantin Silviu , Lundberg Joyce , Lauritzen Stein‐Erik
Published: September 2002

The PU‐2 stalagmite from Ursilor Cave provides the first dated Romanian isotope record for the Holocene. The overall growth rate of the speleothem was 3.5 cm kyr−1, corresponding to a temporal resolution of 142 y between each isotope analysis. The ‘Hendy’ tests indicate that isotopic equilibrium conditions occurred during the formation of PU‐2, and hence that it is suitable for palaeoclimatic studies. The relationship between δ18O and temperature was found to be positive. This can be interpreted either as rain‐out with distance from the west‐northwest ocean source of evaporation or shifts in air mass source with changing North Atlantic Oscillation indices. Applying five U–Th thermal ionisation mass spectrometric (TIMS) dates to a 17.5 cm isotope profile (δ18O and δ13C) along the stalagmite growth axis enabled a tentative interpretation of the palaeoclimate signal over the past 7.1 kyr. Spikes of depleted isotopic δ18O values are centred near ca. 7, ca. 5.2 and ca. 4 ka, reflecting cool conditions. The record shows two warm intervals between ca. 3.8 and ca. 3.2 ka (the maximum warmth) and from ca. 2 to ca. 1.4 ka, when the δ18O values were less negative than present. The ‘Holocene Climate Optimum’ spanning the time interval from ca. 6.8 to ca. 4.4 ka is not well expressed in the PU‐2 stalagmite. Individual spikes of lighter δ13C are interpreted as indicative of periods of heavy rainfall, at ca. 7, ca. 5.5, and ca. 3.5 ka. The overall trend to lighter δ13C in the PU‐2 stalagmite may reflect a gradual decrease in water–rock interaction. The results demonstrate that the effect of North Atlantic oceanic changes extended to the investigated area. Nevertheless, some differences in temporal correlation and intensity of stable isotopic response to these climatic events have been found, but the exact nature of these differences and the underlying mechanism is yet to be determined. Copyright © 2002 John Wiley & Sons, Ltd.
In situ investigation of the chemical composition of ceroid in human atherosclerosis by Raman spectroscopy
Authors: van de Poll Sweder W. E. , Bakker Schut Tom C. , van der Laarse Arnoud , Puppels Gerwin J.
Published: September 2002

Fluorescent lipid peroxidation products (ceroid) form within the atheroma of an atherosclerotic lesion. At present, the initiation and propagation of such oxidative processes in situ are not well understood, in part because of the insolubility of the ceroid deposits. We investigated the chemical composition of ceroid in human atherosclerotic plaque by combining autofluorescence microscopy and Raman spectroscopy. In eight sectioned human atherosclerotic samples, we located granular and ring‐shaped ceroid deposits by autofluorescence microscopy. Subsequently, two‐dimensional Raman maps of the ceroid deposits and surrounding non‐fluorescent atheroma were acquired at 1 µm resolution. These Raman spectra were subjected to a K‐means clustering analysis. By assigning a different color to each cluster, pseudo‐color Raman images of the tissue sections were obtained. From these images the clusters belonging to ceroid and the non‐fluorescent surrounding tissue were selected. The averaged cluster spectra were analyzed by means of a least‐squares fit with the Raman spectra of pure chemical compounds. In addition, the Raman spectra were compared with the Raman spectra of normal and oxidized lipids. Marked differences between the Raman spectra of ceroid and surrounding, non‐fluorescent atheroma were observed, amidst large sample to sample variation in chemical composition. Compared with the non‐fluorescent tissue, the changes in the Raman spectra of the ceroid deposits could best be explained by larger signal contributions from hemoglobin and cholesteryl esters. We conclude that there is a large heterogeneity in the chemical composition of ceroid. Its composition is largely dependent on the chemical constituents of the surrounding atheroma. Heme or heme degradation products are consistently present in the ceroid deposits. Our results support the hypothesis that iron and heme can form complexes with the intravascular lipoproteins, thereby stimulating oxidation and initiating the formation of ceroid. Copyright © 2002 John Wiley & Sons, Ltd.
Near‐infrared multichannel Raman spectroscopy toward real‐time in vivo cancer diagnosis
Authors: Kaminaka Shoji , Ito Toshiaki , Yamazaki Hiroya , Kohda Ehiichi , Hamaguchi Hiro‐o
Published: September 2002

Using a newly developed InP/InGaAsP multichannel detector, we developed a near‐infrared Raman spectroscopic system that can measure human tissues efficiently without interference from fluorescence. This enabled us to measure an in vivo Raman spectrum of live human tissue (skin) in 1 min using fiber probe optics. By applying this system to human lung tissues, we found that Raman spectroscopy makes a clear distinction not only between normal and cancerous tissues but also between two different types of lung carcinomas. The results indicate a promising future for the non‐invasive real‐time Raman diagnosis of cancers. Copyright © 2002 John Wiley & Sons, Ltd.
Fate of foodborne bacterial pathogens in pesticide products
Authors: Guan Tat Yee , Blank Greg , Ismond Anne , Van Acker Rene
Published: September 2002

The effects of diluting concentrated pesticide products with water containing Escherichia coli O157:H7 (human, bovine and ground meat strains), Salmonella typhimurium, Salmonella enteritidis, Shigella sonnei, Shigella flexneri and Listeria monocytogenes were investigated. Individual cultures were inoculated at about 102 colony‐forming units (cfu) ml−1 into the following commercial pesticide products—Roundup, Poast & Merge, Gramoxone, Afolan, 2,4‐D amine, Dithane M45, Benlate, Bravo 500, Ridomil 240EC, Thiram 75WP, Sevin XLR+, Lorsban 4E, Diazinon 500, Ambush 500EC and Lagon 480E—following dilution with sterile tap water to recommended spray application concentrations (pesticide solution). Following incubation at 22 °C for 1 h, survivor levels for all three E coli O157:H7 strains in pesticide solutions of Roundup, Poast & Merge, Gramoxone, Dithane M45, Ridomil 240EC and Lagon 480E were lower (P ≤ 0.05) compared to their survival in water. In several pesticide solutions (Afolan, Bravo 500, Lorsban 4E and Ambush 500EC), survivor levels were no different (P≥0.05) from the control after 1 h; however, by 24 h, population levels of all strains in these four pesticide solutions were higher (P ≤ 0.05) than those observed at 1 h. Overall, similar survivor or growth patterns were observed with the remaining bacteria, with the exception of S flexneri. For this bacterium, survival or growth was poor, especially in Bravo 500, which consistently supported substantial growth of the other micro‐organisms. Time course growth studies over 96 h at 22 °C were conducted with Salmonella, Shigella, Listeria and E coli O157:H7 in solutions of Afolan, Bravo 500, Lorsban 4E and Ambush 500EC. Overall, a 100 to 1060‐fold increase in population was usually obtained in these pesticide solutions by 96 h. Changes in either the initial inoculum level of E coli O157:H7 from about 102 to 104 cfu ml−1 or temperature (from 20–22 to 31 °C) and concentration (from 0.5 to 1.5 times the recommended spray concentration) were shown to affect its growth in the pesticide solutions. The findings of this study indicate that some pesticide products, when diluted using contaminated water, may have the potential to promote growth of pathogens which could increase the risk of more widespread contamination of standing crops, including fruits.

© 2001 Society of Chemical Industry
Effect of irradiation, with and without cooking of maize and kidney bean flours, on porridge viscosity and in vitro starch digestibility
Authors: Rombo George O , Taylor John R N , Minnaar Amanda
Published: September 2002

African traditional weaning foods are usually prepared from starchy flours at a total solids content of 50–100 g l−1, giving a viscosity of 1000–3000 cP which is consumable by infants. These porridges have very low energy and nutrient densities. Processing to reduce the porridge viscosity and improve the energy and nutrient density may help in solving this problem. Maize, kidney bean and their 70:30 composite flours were irradiated at 0–10 kGy at room temperature. Irradiation greatly reduced the viscosity of porridges, probably by starch depolymerisation. Irradiation improved the starch digestibility of raw bean flours, possibly either by inhibiting α‐amylase inhibitors or by weakening the thick cell walls that enclose the starch granules, thus improving accessibility to enzymes. However, in raw maize, cooked maize and cooked bean flours there was maximum starch digestibility at a dose of 2.5 kGy, followed by small but significant decreases in starch digestibility at higher doses, more so in maize than in bean flours. The decrease in digestibility could be due to the formation of inhibitors of amylolytic enzymes (Maillard reactions products) or to the formation of resistant starch. Irradiation doses required to increase the total solids content of traditional maize‐ and/or bean‐based weaning porridges to at least 200 g l−1 do not compromise starch digestibility significantly.

© 2001 Society of Chemical Industry
Effect of toasting time on the browning of sliced bread
Authors: Ramírez‐Jiménez Antonio , García‐Villanova Belén , Guerra‐Hernández Eduardo
Published: September 2002

Slices of wheat bread were toasted for different times until a distinct intensity of brown colour was reached. Two assays were carried out: prolonged toasting times (5–60 min) and reduced toasting times (0.5–5 min). The browning indicators (furosine, available lysine, hydroxymethylfurfural (HMF), colour and absorbance at 284 and 420 nm) were determined. The precision of all indicators used was high (CV < 4%). No furosine or HMF was detected in the dough before baking. The furosine content increased until 7 min (299 mg per 100 g protein) and then decreased to 2.9 mg per 100 g protein at 60 minutes. For the first toasting times (0.5, 1 and 2 min) the furosine content decreased slightly. Available lysine reached losses of 50% after 25 min of heating. The toasting of bread increased HMF values from 12 to 2025 mg kg−1 for the assay at prolonged times of heating and from 1.3 to 4.2 mg kg−1 at reduced times (0.5–5 min). The HMF content decreased (1000 mg kg−1) when the sliced bread was toasted until it burnt. Colour (ΔE, 100 − L*) and absorbance at 284 and 420 nm always increased. High linear correlations (r2 > 0.860) were obtained between browning indicators and time (A284/time, A420/time, 100 − L*/time and HMF/time).

© 2001 Society of Chemical Industry
Volatile compounds in Bacillus‐fermented soybeans
Authors: Leejeerajumnean Arunsri , Duckham S Craig , Owens J David , Ames Jennifer M
Published: September 2002

Thua nao, a traditional, proteolytic, fermented soybean condiment of northern Thailand, was prepared from cooked whole soybeans by natural flora fermentation. The microbial flora during the fermentation was dominated by Bacillus species. The formation of volatile compounds during the fermentation was studied. In addition, the volatile compounds of two samples of commercial dried thua nao and two samples of commercial Japanese natto were analysed. Fermentation led to a large increase in the concentration of total volatile compounds, from 35 µg kg−1 wet weight in cooked soybeans to 3500 µg kg−1 wet weight in 72 h fermented material. The major volatile compounds in fermented beans were 3‐hydroxybutanone (acetoin), 2‐methlybutanoic acid, pyrazines, dimethyl disulphide and 2‐pentylfuran. Sun drying of 72 h fermented material resulted in the loss of 65% of total volatiles, including important aroma compounds. The commercial dried thua nao samples had low concentrations of total volatile compounds (380 µg kg−1 wet weight). It is suggested that improved drying/preservation methods are needed to retain aroma compounds in the traditional products. The natto samples were devoid of aldehydes, aliphatic acids and esters, and sulphur compounds, whereas the thua nao samples contained a diversity of these compounds. Previous investigators have reported these compounds in natto and it is not possible to suggest the existence of systematic differences between the volatile compounds in traditional thua nao prepared with an undefined, mixed microbial flora and those in natto fermented with Bacillus subtilis.

© 2001 Society of Chemical Industry
Response of intestinal proteinase activities to the feeding of isolated winged bean (Psophocarpus tetragonolobus) and soya bean (Glycine max) trypsin inhibitors in rats
Authors: Nishino Naoki , Taniguchi Mayumi , Sakaguchi Ei
Published: September 2002

The antinutritional activities of trypsin inhibitors (TIs) were compared between winged beans (Psophocarpus tetragonolobus) and soya beans (Glycine max). The inhibitors of the two beans were isolated by trypsin‐bound Sepharose 4B, and 50 mg of lyophilised powders were intubated intragastrically into 24 h fasted rats. The activities of trypsin and chymotrypsin were compared after 30, 60 and 180 min in the washings of the upper, middle and lower parts of the small intestine. The elution profiles of TI and non‐TI compounds in the affinity chromatography were similar in the two beans, and the antitryptic activities were concentrated 5.5 and 6.2 times (based on specific activity) for winged beans and soya beans respectively. Regardless of the TI fed to rats, trypsin activity in the upper intestine was suppressed to almost undetectable levels at 30 and 60 min after intubation. The activities in the middle and lower intestines were also substantially lowered when rats were fed winged bean TI, and significant differences were detected at 30 and 60 min after intubation when compared with rats fed soya bean TI. However, at 180 min after feeding, no differences were found in the trypsin activity in any gut segments. Similar inhibitory properties of isolated TIs were observed in chymotrypsin activities in the small intestine. The results suggest that winged bean TI may have greater inhibitory activity on the intestinal proteinase compared with soya bean TI.

© 2001 Society of Chemical Industry
Theoretical comparison of a new and the traditional method to calculate Clostridium botulinum survival during thermal inactivation
Authors: Campanella Osvaldo H , Peleg Micha
Published: September 2002

When published isothermal survival data of Clostridium botulinum spores in the range 101–121 °C were plotted in the form of logS(t) vs t relationships, where S(t) is the momentary survival ratio, they were all non‐linear. They had a noticeable upward concavity, in violation of the assumption that sporal inactivation is a process that follows first‐order reaction order kinetics. They could be described by the power law model logS(t) = − b(T)t
n(T), where b(T) and n(T) are temperature‐dependent coefficients of the order of 0.1–6 and about 0.4 respectively. These coefficients were used to construct simulated survival curves under different heating regimes with a recently proposed model. The model is based on the assumption that the local slope of the non‐isothermal survival curve, or the momentary inactivation rate, is determined solely by the momentary temperature and survival ratio, which in turn are functions of the population thermal history. The survival curves calculated with this model differ considerably from those produced by the standard method based on the traditional D and Z values. The shortcomings of the standard model are that these values depend on the number of points taken for the regression, and that its predicted survival ratios depend on the selected reference temperature. The differential equation which is proposed to replace it can be solved numerically using a program such as Mathematica®. Its predictions solely depend on the observed survival patterns under isothermal conditions and not on any preconceived kinetic model. Nevertheless, the method still needs verification with experimental non‐isothermal survival data, as has already been done with Listeria and Salmonella cells.

© 2001 Society of Chemical Industry
Minerals, phytic acid, tannin and rutin in buckwheat seed milling fractions
Authors: Steadman Kathryn J , Burgoon Monica S , Lewis Betty A , Edwardson Steven E , Obendorf Ralph L
Published: September 2002

The composition of common buckwheat (Fagopyrum esculentum Moench) seed milling fractions depends upon the relative abundance of various seed tissues in each. Fancy (light) flour contains mainly central endosperm, while the bran milling fraction has seed coat and some embryo tissues. Phytate, found in protein bodies of embryo and aleurone cells, is the major storage form of phosphorus, potassium, magnesium and some microelements in seeds. Phytic acid (35–38 g kg−1) and minerals are concentrated in bran, a milling fraction with high concentrations of phytate‐rich tissues. Polyphenolics, including condensed tannins (proanthocyanidins), are also concentrated in bran (11–15 g kg−1). Rutin is concentrated in the hull of common buckwheat (0.8–4.4 g kg−1). Rutin concentration is low (0.2–0.3 g kg−1) in groats of common buckwheat but higher (0.7–0.8 g kg−1) in bran containing hull fragments. Rutin is 300‐fold more concentrated (81 g kg−1) in groats of tartary buckwheat (Fagopyrum tataricum (L) Gaertn) than in groats of common buckwheat. Only small amounts of quercetin were detected. Bran is a concentrated source of phytic acid and tannins, a consideration in consumption of large amounts of buckwheat bran for nutritional or medicinal purposes.

© 2001 Society of Chemical Industry
Dry bean cultivar characterisation by isoelectric focusing electrophoresis in polyacrylamide gel
Authors: Ruiz Guerrero Rosa M , Ortiz García Rafael , Álvarez Martínez Pedro
Published: September 2002

A Spanish pinto bean local cultivar ‘Pinta’ was analysed by a standard electrophoretic technique, isoelectric focusing electrophoresis, in order to develop and test a reliable method of solving such food industry problems as fraud, adulteration and the identification and registration of different cultivars of legume seeds. The corresponding dry bean type protein extract was subjected to isoelectric focusing electrophoresis in polyacrylamide gel (IEF‐PAGE), and the resulting data were then studied with a suitable objective chemometric evaluation technique. Applying the Rasch model to the appropriate electrophoretic results, this Spanish dry bean type was clearly characterised by the order of the chemometric measures attributed by the model to each electrophoretic band in its proteinogram. The same chemometric technique was then applied to three more dry bean cultivars. They also showed their own characteristic order of the electrophoretic bands in their corresponding proteinograms. Consequently, this method could well be a valuable tool for legume seed identification and registration. The problems intrinsic to electrophoresis were solved with the Rasch model techniques.

© 2001 Society of Chemical Industry.
The presence of bioactive peptides in hydrolysates prepared from processing waste of sardine (Sardina pilchardus)
Authors: Ravallec‐Plé Rozenn , Charlot Caroline , Pires Carla , Braga Vera , Batista Irineu , Van Wormhoudt Alain , Le Gal Yves , Fouchereau‐Péron Martine
Published: September 2002

A proteolytic enzyme, Alcalase®, was used to produce partly digested proteins from cooked wastes of sardine (Sardina pilchardus). The presence of biologically active molecules was investigated in these hydrolysates prepared under various conditions of time and enzyme/substrate ratio. By means of radioimmunoassays and mitogenic and radioreceptor assays, the presence of molecules related to secretagogue peptides, growth factors and calcitonin gene‐related peptide (CGRP) respectively was detected in the hydrolysates. Exclusion chromatography permits the conclusion that the biological activity of the different fractions is related to their size.

© 2001 Society of Chemical Industry