bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular epidemiology of enterovirus 71 infection in the Western Pacific Region
Authors: Shimizu Hiroyuki , Utama Andi , Onnimala Napa , Li Chen , Li‐Bi Zhang , Yu‐Jie Ma , Pongsuwanna Yaowapa , Miyamura Tatsuo 
Published: April 2004

Abstract
Background
: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection.
Methods
: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains.
Results
: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively.
Conclusion
: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co‐circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent.
Molecular epidemiology of HIV: Tracking AIDS pandemic
Authors: Takebe Yutaka , Kusagawa Shigeru , Motomura Kazushi 
Published: April 2004

Abstract
Background
: Human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) epidemic is a global threat to maternal and child health, especially in developing countries. It is estimated that 800 000 children are infected and 580 000 children die of AIDS‐related illnesses every year. Molecular epidemiology has been a useful tool in analyzing the origin of HIV and tracking the course of global HIV spread. This article provides an overview of recent advances in the field of molecular epidemiology of HIV across the world, and discuss the biological implications.
Methods
: Based on the near full‐length or partial nucleotide sequence information, the phylogeny and recombinant structure of HIV strains are analyzed. Using genotype classification of HIV as a molecular marker, the origin and the genesis of HIV epidemic are investigated.
Results
: The HIV‐1 group M, a major HIV group responsible for current AIDS pandemic, began its expansion in human population approximately 70 years ago and diversified rapidly over time, now comprising a number of different subtypes and circulating recombinant forms (CRF). Of note, recent studies revealed that new recombinant strains are arising continually, becoming a powerful force in the spread of HIV‐1 across the globe.
Conclusion
: Global dissemination of HIV is a dramatic and deadly example of recent genome emergence and expansion. Molecular epidemiological investigation is expected to provide information critical for prevention and future vaccine strategies.
Periventricular low intensities on fluid attenuated inversion recovery imaging in the newborn infant: Relationships to the clinical data and long‐term outcome
Authors: Iwata Osuke , Iwata Sachiko , Tamura Masanori , Nakamura Tomohiko , Hirabayashi Shinnichi , Fueki Noboru , Kondou Yoshiaki , Hizume Eriko , Kihara Hideki 
Published: April 2004

Abstract
Background
: The author's previous study showed that it is possible to predict the severity of white matter injury in early infancy by using fluid attenuated inversion recovery (FLAIR) imaging. A follow‐up study was performed in order to assess the correlation between the incidence of periventricular low intensities on FLAIR imaging (F‐PVLI) and the clinical data including the physiological variables at birth and the long‐term outcome of the infant.
Methods
: The authors reviewed MRI of 328 newborn infants, which were obtained before 2 months corrected age. Abnormal findings in the periventricular white matter and other part of the brain were recorded. Periventricular abnormal intensities were sorted into four groups according to the FLAIR grade, which comprised normal, F‐PVLI 1 (focal), F‐PVLI 2 (extensive), cystic periventricular leukomalacia (C‐PVL), and diffused leukomalacia.
Results
: Significantly more periventricular abnormal intensities were detected by FLAIR imaging than by conventional T1 and T2 weighted imaging. In the groups of F‐PVLI 2 and C‐PVL, the birth weight (BW), gestational age (GA), blood pH and base excess at birth were significantly lower than in the normal group. However, when the study population was defined into very low birth weight infants, F‐PVLI 2 had significantly larger BW and GA than normal. The FLAIR grade had a strong correlation with the developmental outcome at 12 and 36 months corrected age.
Conclusion
: F‐PVLI is a silent but very important white matter injury, which has many features in common with C‐PVL. FLAIR imaging could be a strong tool in screening newborn infants at high risk of neurological impairment.
Helminth risks associated with mixed game and livestock interactions in and around Lake Mburo National Park, Uganda
Authors: Ocaido M. , Siefert L. , Baranga J. 
Published: April 2004

AbstractA study was performed in and around Lake Mburo National Park (LMNP) to identify common helminths that parasitize both game and livestock. Various techniques including floatation, Baerman and sedimentation tests, faecal culturing and post‐mortem were used to identify helminths recovered during the survey. Identification was based on egg, larval and adult helminth developmental stages. Results showed that 22 species of parasitic nematodes, lungworms, ascaris, trematodes and tapeworms occur in both wild game and livestock found in and around the national park. The significance of the findings to helminth cross‐infection among game, livestock and man is discussed.
Fish species and trophic diversity of haplochromine cichlids in the Kyoga satellite lakes (Uganda)
Authors: Mbabazi Dismas , Ogutu‐Ohwayo R. , Wandera S. B. , Kiziito Y. 
Published: April 2004

AbstractPrior to the 1980s, lakes Kyoga and Victoria previously supported an exceptionally diverse haplochromine fish fauna comprising at least 11 trophic groups. The species and trophic diversity in these lakes decreased when the introduced Nile perch depleted haplochromine stocks. From December 1996 to October 1998, we studied species and trophic diversity of haplochromine fishes in six satellite lakes without Nile perch in the Kyoga basin and compared them with the Kyoga main lake against historical data from Lake Victoria where Nile perch were introduced. Forty‐one species were found in the study area, of which, the Kyoga satellite lakes contributed 37 species in comparison to only 14 from the Kyoga main lake. Analysis of trophic diversity based on 24 species that contained food material revealed seven haplochromine trophic groups (insectivores, peadophages, piscivores, algal eaters, higher plant eaters, molluscivores and detritivores) in the Kyoga satellite lakes in comparison to two trophic groups (insectivores and molluscivores) in the Kyoga main lake. Many of the species and trophic groups of haplochromines depleted by the introduced Nile perch in lakes Kyoga and Victoria still survive in the Kyoga satellite lakes. This is attributed to the absence of Nile perch in those lakes. Nile perch has been prevented from spreading into the satellite lakes by swamp vegetation that separate them from the main lakes. If these swamps prevent Nile perch from spreading into the lakes, it is possible to conserve fish species, especially haplochromines, which are threatened by introduction of Nile perch in the main lakes.
Adulthood nicotine treatment alleviates behavioural impairments in rats neonatally treated with quinpirole: possible roles of acetylcholine function and neurotrophic factor expression
Authors: Brown Russell W. , Thompson Kenyatta D. , Thompson Kimberly N. , Ward J. Jeffrey , Thacker Stephanie K. , Williams Michael T. , Kostrzewa Richard M. 
Published: April 2004

AbstractIncreases in dopamine D2 receptor sensitivity are known to be common in drug abuse and neurological disorders. Past data from this laboratory have shown that long‐term increases in D2 sensitivity can be produced by quinpirole treatment (a D2/D3 agonist) during early development. The present investigation was designed to test the hypothesis that nicotine administration in adulthood would reduce both cognitive and skilled reaching impairments produced by increases in D2 sensitivity. Female Sprague–Dawley rats were treated with quinpirole (1 mg/kg) or saline from postnatal day 1 (PD 1) to PD 21. Beginning in adulthood (PD 61), rats were treated with nicotine (0.3 mg/kg free base) or saline twice daily for 14 consecutive days before behavioural testing commenced. Animals neonatally treated with quinpirole demonstrated performance deficits on the Morris water task and a skilled reaching task compared to controls. Deficits on both tasks were completely alleviated by adulthood nicotine treatment. Animals neonatally treated with quinpirole demonstrated a significant 36% decrease of ChAT in the hippocampus compared to saline controls that was partially eliminated by nicotine. Additionally, neonatal quinpirole produced a significant decrease in hippocampal NGF content compared to controls, however, nicotine failed to alleviate this decrease in NGF. The results of this investigation demonstrate that long‐term increases in dopamine D2 receptor sensitivity produce significant decreases in hippocampal cholinergic and NGF expression that may result in cognitive impairment. Nicotine alleviates both cognitive and skilled reaching impairments caused by increases in D2 sensitivity, but the mechanism through which nicotine is acting is currently unknown.
Contribution of the ventral tegmental area to cocaine‐seeking maintained by a drug‐paired conditioned stimulus in rats
Authors: Di Ciano Patricia , Everitt Barry J. 
Published: April 2004

AbstractStimuli paired with cocaine can maintain cocaine‐seeking as conditioned reinforcers. Although converging evidence implicates a role for the ventral tegmental area (VTA) in the primary reinforcing effects of drugs of abuse, the role of the VTA in mediating associative influences over drug‐seeking remains to be determined. The present study therefore investigated the contribution to CS‐maintained cocaine‐seeking under a second‐order schedule of reinforcement of the VTA, and its terminal regions, the nucleus accumbens (NAcc) core and basolateral amygdala (BLA), previously shown to be critical for the acquisition of this behaviour. Inactivation of the VTA or NAcc core by direct infusion of a mixture of the GABAA and GABAB receptor agonists, baclofen and muscimol, decreased cocaine‐seeking when rats were drug‐free, while drug‐seeking after self‐administered cocaine was increased only when they were infused into the NAcc core. Inactivation of the BLA had no effect on drug‐seeking. These results are discussed with reference to critical and distinct contributions of the VTA, NAcc core and BLA to drug‐seeking maintained by conditioned reinforcers
Independent on‐line control of the two hands during bimanual reaching
Authors: Diedrichsen Jörn , Nambisan Rohit , Kennerley Steve W. , Ivry Richard B. 
Published: April 2004

AbstractMany studies on bimanual coordination have shown that people exhibit a preference for mirror‐symmetric movements. We demonstrate that this constraint is absent when bimanual reaching movements are made to visual targets. We investigated the ability of humans to make on‐line adjustments during such movements when one or both targets were displaced during the initial phase of the movements. Adjustments were as efficient during bimanual as unimanual movements, even when two adjustments had to be made simultaneously. When one target was displaced in the bimanual condition, the hand reaching to that target adjusted efficiently to the displacement. However, a small transient perturbation in the trajectory of the other hand was also observed. This perturbation was in the same direction as the displacement, rather than in mirror‐symmetric direction. A control experiment demonstrated that these perturbations could be elicited by visual information alone, but that they were also influenced by whether an adjustment was required in the trajectory of the other hand. Our results demonstrate near independent control of the two arms during visually guided reaching. The subtle interference observed between the arms reflects interactions between target‐related representations in visual coordinates rather than between movement‐related representations in joint‐ or muscle‐coordinates.
Orexins (hypocretins) directly interact with neuropeptide Y, POMC and glucose‐responsive neurons to regulate Ca2+ signaling in a reciprocal manner to leptin: orexigenic neuronal pathways in the mediobasal hypothalamus
Authors: Muroya Shinji , Funahashi Hisayuki , Yamanaka Akihiro , Kohno Daisuke , Uramura Kazuhide , Nambu Tadahiro , Shibahara Megumi , Kuramochi Motoki , Takigawa Morikuni , Yanagisawa Masashi , Sakurai Takeshi , Shioda Seiji , Yada Toshihiko 
Published: April 2004

AbstractOrexin‐A and ‐B (hypocretin‐1 and ‐2) have been implicated in the stimulation of feeding. Here we show the effector neurons and signaling mechanisms for the orexigenic action of orexins in rats. Immunohistochemical methods showed that orexin axon terminals contact with neuropeptide Y (NPY)‐ and proopiomelanocortin (POMC)‐positive neurons in the arcuate nucleus (ARC) of the rats. Microinjection of orexins into the ARC markedly increased food intake. Orexins increased cytosolic Ca2+ concentration ([Ca2+]i) in the isolated neurons from the ARC, which were subsequently shown to be immunoreactive for NPY. The increases in [Ca2+]i were inhibited by blockers of phospholipase C (PLC), protein kinase C (PKC) and Ca2+ uptake into endoplasmic reticulum. The stimulation of food intake and increases in [Ca2+]i in NPY neurons were greater with orexin‐A than with orexin‐B, indicative of involvement of the orexin‐1 receptor (OX1R). In contrast, orexin‐A and ‐B equipotently attenuated [Ca2+]i oscillations and decreased [Ca2+]i levels in POMC‐containing neurons. These effects were counteracted by pertussis toxin, suggesting involvement of the orexin‐2 receptor and Gi/Go subtypes of GTP‐binding proteins. Orexins also decreased [Ca2+]i levels in glucose‐responsive neurons in the ventromedial hypothalamus (VMH), a satiety center. Leptin exerted opposite effects on these three classes of neurons. These results demonstrate that orexins directly regulate NPY, POMC and glucose‐responsive neurons in the ARC and VMH, in a manner reciprocal to leptin. Orexin‐A evokes Ca2+ signaling in NPY neurons via OX1R–PLC–PKC and IP3 pathways. These neural pathways and intracellular signaling mechanisms may play key roles in the orexigenic action of orexins.
Primary somatosensory cortex modulation of tactile responses in nucleus gracilis cells of rats
Authors: Malmierca Eduardo , Nuñez Angel 
Published: April 2004

AbstractCorticofugal influences from the primary somatosensory cortex to the gracilis nuclei were studied with single unit recordings performed in urethane‐anaesthetized rats. Two types of neurons were identified: low firing rate (LF) neurons, which could be activated antidromically by medial lemniscus stimulation; and high firing rate (HF) neurons. The effects of electrically stimulating the contralateral primary somatosensory cortex were studied in two situations: when the stimulated cortical area and specific gracilis cells had overlapping receptive fields and when the receptive fields of the cells and primary somatosensory cortex did not overlap. Cortical stimulation facilitated cortical and tactile responses in most gracilis neurons (68% and 58% for LF and HF neurons, respectively) with overlapping receptive fields. When receptive fields were different, cortical stimulation inhibited tactile response in most LF neurons (58%) and some HF neurons (20%). Trains of cortical shocks during sensory stimulation demonstrated that the facilitatory and inhibitory effects outlasted the stimulation period by 5 min. The facilitatory effect was decreased by iontophoretic application of the N‐methyl‐D‐aspartate (NMDA) receptor antagonist APV (50 mm). However, APV did not modify the intensity of the tactile response inhibition in cells with nonoverlapping receptive fields, although, its duration was decreased (<5 min). Iontophoretic application of the γ‐aminobutyric acid (GABA)A antagonist bicuculline (20 mm) blocked the cortically evoked inhibition in cells with nonoverlapping receptive fields. The results indicate that the somatosensory cortex precisely controls somatosensory transmission throughout the gracilis nucleus by means of NMDA and GABAA receptor activation.
RGS21 is a novel regulator of G protein signalling selectively expressed in subpopulations of taste bud cells
Authors: Von Buchholtz Lars , Elischer Andrea , Tareilus Erwin , Gouka Robin , Kaiser Carmen , Breer Heinz , Conzelmann Sidonie 
Published: April 2004

AbstractG‐protein‐mediated signalling processes are involved in sweet and bitter taste transduction. In particular, the G protein α‐subunit gustducin has been implicated in these processes. One of the limiting factors for the time‐course of cellular responses induced by tastants is therefore the intrinsic GTPase activity of α‐gustducin, which determines the lifetime of the active G protein complex. In several signalling systems specific ‘regulator of G protein signalling’ (RGS) proteins accelerate the GTPase activity of G protein α‐subunits. Using differential screening approaches, we have identified a novel RGS protein termed RGS21, which represents the smallest known member of this protein family. Reverse transcription polymerase chain reaction and in situ hybridization experiments demonstrated that RGS21 is expressed selectively in taste tissue where it is found in a subpopulation of sensory cells. Furthermore, it is coexpressed in individual taste cells with bitter and sweet transduction components including α‐gustducin, phospholipase Cβ2, T1R2/T1R3 sweet taste receptors and T2R bitter taste receptors. In vitro binding assays demonstrate that RGS21 binds α‐gustducin in a conformation‐dependent manner and has the potential to interact with the same Gα subtypes as T1R receptors. These results suggest that RGS21 could play a regulatory role in bitter as well as sweet taste transduction processes.
Functional importance of Ca2+‐activated K+ channels for lysophosphatidic acid‐induced microglial migration
Authors: Schilling Tom , Stock Christian , Schwab Albrecht , Eder Claudia 
Published: April 2004

AbstractMigration of microglial cells towards damaged tissue plays a key role in central nervous system regeneration under pathological conditions. Using time lapse video microscopy we show that lysophosphatidic acid (LPA) enhances chemokinetic migration of murine microglial cells. In the presence of 1 µm LPA, the mean migration rate of microglial cells was increased 3.8‐fold. In patch‐clamp studies we demonstrate that LPA induces activation of a Ca2+‐activated K+ current. Microglial Ca2+‐activated K+ currents were abolished by either 50 nm charybdotoxin or 10 µm clotrimazole. In contrast, 5 µm paxilline did not have any significant effects on Ca2+‐activated K+ currents. The LPA‐stimulated migration of microglial cells was inhibited by blockers of IKCa1 Ca2+‐activated K+ channels. The mean migration rate of LPA‐stimulated cells was decreased by 61% in the presence of 50 nm charybdotoxin or by 51% during exposure to 10 µm clotrimazole. Microglial migration was not inhibited by 5 µm paxilline. It is concluded that IKCa1 Ca2+‐activated K+ channels are required for LPA‐stimulated migration of microglial cells.
Gender differences in regional cutaneous microcirculatory responses to capsaicin
Authors: Ferrell W.R. , Wong B.B. , Lockhart J.C. , Ramsay J.E. 
Published: April 2004

AbstractVascular responsiveness between healthy male and female subjects to capsaicin, an agent promoting neuropeptide release, was compared. Changes in skin perfusion were measured non‐invasively using laser Doppler imaging. Topical application of a 3% solution of capsaicin to the dorsum of the hand resulted in vasodilatation in nine of 10 male subjects, but in less than half of the female subjects. Responses to capsaicin at the shin were smaller but did not show gender differences. Fingertip temperature was significantly lower in females compared with males and this correlated (r = 0.54, P < 0.01) with the maximum response to capsaicin. These effects were specific to capsaicin as endothelium‐dependent and ‐independent vasodilator mechanisms, assessed non‐invasively by iontophoresis of acetylcholine and sodium nitroprusside, respectively, showed no gender differences. These findings suggest a specific anomaly in capsaicin‐sensitive vasodilator mechanisms in some subjects, perhaps indicative of subclinical expression of Raynaud's phenomenon.
Studying long‐term effect of phenytoin either alone or combined with ascorbic acid on the anesthetic effect of urethane in rats
Authors: El Desoky Ehab S. , Abdulla Mostafa Mh 
Published: April 2004

AbstractPhenytoin is an anticonvulsant drug known to interact with many other drugs. Previous data suggest that chronic administration of phenytoin delays urethane‐induced loss of righting reflex (LRR) and this phenomenon being potentiated by concomitant administration of ascorbic acid (ASC). Therefore, we examined how phenytoin at two different doses combined or not with ASC (fixed dose) interact with both the latency to, and the duration for urethane‐induced LRR in experimental rats. The results showed that lower dose of phenytoin (60 mg/kg rat b.i.d.) has significantly shortened the duration of LRR while higher dose of the drug (120 mg/kg b.i.d.) has delayed the latency to LRR (cut‐off period of 15 min). Furthermore, addition of ASC to any of the two doses of phenytoin gave results similar to that observed for latency to and duration of LRR when phenytoin was given alone at the higher dose (120 mg/kg b.i.d.).Our data suggest a resistant effect of chronic administration of phenytoin on latency to and/or duration of loss righting reflex induced by urethane in experimental animals. A dose–response relationship of phenytoin in this regard is expected and needs further investigations. The resistant effect of phenytoin on righting reflex has been augmented when ASC was chronically given in combination. This result supports a possible interaction between the two drugs and needs further investigations at both experimental and clinical levels.