bluuebunny/crossref_metadata_2025 huggingface dataset:
Prolonged survival of mouse epididymal spermatozoa stored at room temperature
Authors: Sato Masahiro , Ishikawa Aki , Nagashima Ayako , Watanabe Toshiteru , Tada Norihiro , Kimura Minoru
Published: August 2002

Summary: The viability and fertility of isolated mouse epididymal spermatozoa kept for up to 7 days at various temperatures (4°C, 22°C, and 37°C) were determined. Spermatozoa kept for 3 days at 22°C were still active, while those kept at 37°C or 4°C exhibited great reduction in motility within 2 days after isolation. In vitro fertilizing abilities of spermatozoa left for 0, 1, 2, and 3 days at 22°C were 69.2, 32.5, 9.5, and 4.9%, respectively, when the cleavage rate to two‐cell stage was examined. Transfer of two‐cell embryos produced in vitro with spermatozoa left for 1, 2, and 3 days at 22°C resulted in production of fetuses with efficiencies of respectively 30.2, 11.5, and 16.7%, which were lower (63.3%) than that of embryos derived from in vitro fertilization with fresh spermatozoa. These findings indicate that spermatozoa kept for up to 3 days at 22°C can fertilize oocytes, although at relatively low efficiency. genesis 31:147–155, 2001. © 2001 Wiley‐Liss, Inc.
Myelin basic protein induces heme oxygenase‐1 in human astroglial cells
Authors: Businaro Rita , Fabrizi Cinzia , Caronti Brunella , Calderaro Caterina , Fumagalli Lorenzo , Lauro Giuliana M.
Published: August 2002

Heme oxygenase‐1 (HO‐1), also known as heat‐shock protein 32 (HSP‐32), is induced in many cells by a large variety of stimuli. Its induction in nervous system cells following toxic and oxidative stress was suggested to play a protective role. Its presence was recently detected by immunohistochemical studies at the level of inflammatory lesions of rat experimental autoimmune encephalomyelitis. In the present study, we demonstrate that myelin basic protein (MBP) induces HO‐1 in human astroglial cells, as shown by Western blots and RT‐PCR. Proteolytic fragments derived from the whole MBP show a different behavior in the HO‐1 induction: MBP152‐167 was able to produce a light but still significant increase in HO‐1 mRNA and protein levels, whereas MBP68‐84 was not. The increase in HO‐1 production seems to be mediated by a Ca2+‐dependent mechanism, since MBP addition to astrocytoma cultures induced a strong and immediate increment of [Ca2+]i increase; MBP152‐167 elicited a delayed and less pronounced [Ca2+]i increase; no [Ca2+]i changes were induced following cell treatment with MBP68‐84. NO pathway involvement in the induction of HO‐1 by MBP was ruled out since the expression of the inducible isoform of nitric oxide synthase was not upregulated in treated cells, neither nitrite levels were modified, as demonstrated by Greiss reaction. The possible significance of HO‐1 induction following MBP stimulation is discussed. GLIA 37:83–88, 2002. © 2002 Wiley‐Liss, Inc.
Oligodendrocytes from human donors differ in resistance to herpes simplex virus 1 (HSV‐1)
Authors: Kastrukoff Lorne F. , Kim Seung U.
Published: August 2002

Primary cultures of human oligodendrocytes (HOLs) were established from six different donors. Differences in resistance to infection with herpes simplex virus 1 (HSV‐1) were determined between the primary cultures of HOL in tissue culture infective dose 50 (TCID50), indirect immunofluoresence (IF), and serial electron microscopy (EM) studies. Virus production at different multiplicities of infection (MOIs) indicated that differences in HSV‐1 replication were statistically significant and MOI‐dependent. Overall, virus yield from the HOL cultures infected at an MOI of 1 increased up to 6 days postinfection (PI); no additional enhancement occurred at 7 days PI. However, differences in the replication capacity of the six HOL cultures observed at 5 days PI persisted at 6 and 7 days PI. When taken together, the results of these investigations indicate that, similar to experimental animals, resistance to HSV‐1 differs between primary cultures of HOL and is donor‐dependent. The results also raise the possibility that similar to experimental animals, resistance to HSV‐1, mediated at the level of HOL, may be genetically determined. Furthermore, permissive infections of primary cultures of HOL were established with HSV‐1 over a wide range of MOIs, similar to results obtained with viral infection of primary murine oligodendrocytes, but neither latent nor abortive infections of HOL were induced in vitro, even at very low MOIs. Resistance to HSV‐1, mediated by glial cells, is a nonimmune mechanism that may influence the development of acute CNS infection in man as well as individual susceptibility to this virus. GLIA 38:87–92, 2002. © 2002 Wiley‐Liss, Inc.
Distribution of two splice variants of the glutamate transporter GLT‐1 in rat brain and pituitary
Authors: Reye Peter , Sullivan Robert , Scott Heather , Pow David V.
Published: August 2002

We have performed immunocytochemistry on rat brains using a highly specific antiserum directed against the originally described form of the glutamate transporter GLT‐1 (referred to hereafter as GLT‐1α), and another against a C‐terminal splice variant of this protein, GLT‐1B. Both forms of GLT‐1 were abundant in rat brain, especially in regions such as the hippocampus and cerebral cortex, and macroscopic examination of sections suggested that both forms were generally regionally coexistent. However, disparities were evident; GLT‐1α was present in the intermediate lobe of the pituitary gland, whereas GLT‐1B was absent. Similar marked disparities were also noted in the external capsule, where GLT1A labeling was abundant but GLT‐1B was only occasionally encountered. Conversely, GLT‐1B was more extensively distributed, relative to GLT‐1α, in areas such as the deep cerebellar nuclei. In most regions, such as the olfactory bulbs, both splice variants were present but differences were evident in their distribution. In cerebral cortex, patches were evident where GLT‐1B was absent, whereas no such patches were evident for GLT‐1α. At high resolution, other discrepancies were evident; double‐labeling of areas such as hippocampus indicated that the two splice variants may either be differentially expressed by closely apposed glial elements or that the two splice variants may be differentially targeted to distinct membrane domains of individual glial cells. GLIA 38:246–255, 2002. © 2002 Wiley‐Liss, Inc.
Transient expression of the NG2 proteoglycan by a subpopulation of activated macrophages in an excitotoxic hippocampal lesion
Authors: Bu Jie , Akhtar Nadia , Nishiyama Akiko
Published: August 2002

Cells that express the NG2 proteoglycan (NG2+ cells) constitute a large glial population in the normal mature rodent brain. They can differentiate into oligodendrocytes but are distinct from mature oligodendrocytes, astrocytes, microglia, and neurons. Changes in NG2+ cells were examined in kainic acid‐induced excitotoxic lesions of the hippocampus, and the relationship between NG2+ cells and reactive astrocytes and microglia was investigated between 1 and 90 days after lesioning. Two types of reactive NG2+ cells with altered morphology and increased NG2 immunoreactivity were observed in the lesion. Early changes, consisting of an increase in NG2 immunoreactivity and the number of processes, were apparent 24 h after lesioning and persisted through 3 months. These cells were distinct from reactive astrocytes or activated microglia/macrophages. A second type of reactive NG2+ cells appeared 2 weeks after injection, following an influx of macrophages. They had large, round cell bodies with short processes and expressed the microglia/macrophage antigens OX42 and ED1. Single cells coexpressing NG2 and macrophage/microglial antigens could be isolated from the lesion. The number of NG2+/OX42+ cells gradually declined and disappeared by 3 months after injection. They did not express glial fibrillary acidic protein or the alpha receptor for platelet‐derived growth factor, indicating that they are distinct from astrocytes or oligodendrocyte progenitor cells. Cells that coexpressed NG2 and OX42 were never observed in hippocampal slice cultures treated with kainic acid, suggesting that NG2+/OX42+ cells are not derived from endogenous resident brain cells. These findings demonstrate that NG2 expression is transiently upregulated on activated macrophages/microglia that appear during the chronic stage in an excitotoxic lesion in the adult CNS. GLIA 34:296–310, 2001. © 2001 Wiley‐Liss, Inc.
Apoptosis of inflammatory cells in immune control of the nervous system: Role of glia
Authors: Pender Michael P. , Rist Michael J.
Published: August 2002

The elimination of inflammatory cells within the central nervous system (CNS) by apoptosis plays an important role in protecting the CNS from immune‐mediated damage. T cells, B cells, macrophages, and microglia all undergo apoptosis in the CNS. The apoptotic elimination of CNS‐reactive T cells is particularly important, as these cells can recruit and activate other inflammatory cells. T‐cell apoptosis contributes to the resolution of CNS inflammation and clinical recovery from attacks of experimental autoimmune encephalomyelitis (EAE), an animal model of the demyelinating disease multiple sclerosis (MS). T‐cell apoptosis in the CNS in EAE occurs in both an antigen‐specific and an antigen‐nonspecific manner. In antigen‐specific T‐cell apoptosis, it is proposed that T cells that recognize their antigen in the CNS, such as CNS‐reactive T cells, are deleted by the process of activation‐induced apoptosis after activation of the T‐cell receptor. This may result from the ligation of T‐cell death receptors (such as CD95 (Fas) or tumor necrosis factor (TNF) receptor 1) by CD95 ligand (CD95L) or TNF expressed by the same T cell or possibly by microglia, astrocytes or neurons. Inadequate costimulation of the T cell by antigen‐presenting glial cells may render T cells susceptible to activation‐induced apoptosis. T cells expressing CD95 may also die in an antigen‐nonspecific manner after interacting with glial cells expressing CD95L. Other mechanisms for antigen‐nonspecific T‐cell apoptosis include the endogenous release of glucocorticosteroids, deprivation of interleukin‐2, and the release of nitric oxide by macrophages or glia. Apoptosis of autoreactive T cells in the CNS is likely to be important in preventing the development of autoimmune CNS diseases such as MS. GLIA 36:137–144, 2001. © 2001 Wiley‐Liss, Inc.
Peripheral astrocyte processes: Monitoring by selective immunostaining for the actin‐binding ERM proteins
Authors: Derouiche Amin , Frotscher Michael
Published: August 2002

Astrocytes extend thin lamellate processes in the neuropil, in particular around synapses, where they can modulate synaptic function or mediate glial–neuronal communication. Previous studies have shown that these lamellate perisynaptic processes change their shape in response to neuronal activity, but the underlying mechanisms have remained unclear. Similarly, the molecular composition of these fine, sheet‐like astrocytic processes (often 50–100 nm wide) is not understood but has to be related to their dynamic properties. To this end, we have studied the presence of ezrin, radixin, and moesin (ERM proteins) in the rat hippocampus and in primary cultured astrocytes, applying immunoperoxidase, immunofluorescence, and immunogold techniques. These three ERM proteins are known as actin‐binding proteins that link the cell membrane to the actin cytoskeleton, particularly in microvillus‐bearing epithelial cells. In cell culture, anti‐ezrin and antiradixin, but not antimoesin, antibodies were specific for astrocytes, which often displayed selective staining of filopodia and microvilli. Nonoverlapping visualization of astrocytic peripheral and stem processes was obtained by immunocytochemical double labeling for ezrin and GFAP, respectively. In sections of rat hippocampus, homogeneous labeling of the neuropil, but not of cell layers, resulted from immunostaining of fine, peripheral astrocyte processes, as confirmed ultrastructurally. Our data show that the fine peripheral processes of astrocytes, which also constitute the perisynaptic glial sheath, are specialized in that they contain characteristic actin‐associated molecules, likely to contribute to their dynamic properties. Applying anti‐ezrin and anti‐radixin as selective markers, plasticity of these perisynaptic glial processes can be analyzed. GLIA 36:330–341, 2001. © 2001 Wiley‐Liss, Inc.
SCIP/Oct‐6, Krox‐20, and desert hedgehog mRNA expression during CNS remyelination by transplanted olfactory ensheathing cells
Authors: Smith P.M. , Sim F.J. , Barnett S.C. , Franklin Robin J.M.
Published: August 2002

Olfactory ensheathing cells (OECs), although having a separate developmental origin to Schwann cells, are able to generate myelin sheaths following transplantation into areas of CNS demyelination that are remarkably similar to those made by Schwann cells. The transcriptional control of Schwann cell myelination has been well documented, in particular the role of SCIP/Oct‐6 and Krox‐20. It is not known, however, whether these transcription factors are also expressed when OECs assume a myelinating phenotype. In this study, we addressed this question by using a transplantation approach to generate myelinating OECs and then examined the expression of SCIP/Oct‐6 and Krox‐20 mRNA by in situ hybridization using oligonucleotide probes. We also examined the expression of desert hedgehog (Dhh), a Schwann cell–derived signaling molecule that is responsible for regulating the development of the connective tissue elements in peripheral nerve, which bear similarities to the morphologies adopted by nonmyelinating transplanted cells. Our results indicate that both Krox‐20 and Dhh mRNA are strongly expressed by transplanted OECs, with SCIP mRNA present at much lower levels. The expression of Krox‐20 relative to the expression of P0 mRNA by the transplanted OECs is consistent with its playing a similar role in OEC myelination to that in Schwann cell myelination, while the expression of Dhh suggests a possible mechanism for the diverse morphologies that cells adopt following OEC transplantation into the damaged CNS. Taken together, our results provide further evidence for the close similarity of OECs and Schwann cells and suggest that, despite their separate origins, the manner in which they generate a peripheral‐type myelin sheath involves similar regulatory mechanisms. GLIA 36:342–353, 2001. © 2001 Wiley‐Liss, Inc.
Three‐dimensional distribution of astrocytes in zebrafish spinal cord
Authors: Kawai Hitomi , Arata Noriko , Nakayasu Hiroshi
Published: August 2002

We prepared a monoclonal antibody (A‐22) that recognizes a 60‐kDa protein in the zebrafish brain. The antigen is distributed throughout the brain but is not found outside it. The antibody recognizes star‐shaped cells with long processes in the spinal cord. All A‐22‐positive cells are also GFAP‐immunopositive, but there are GFAP‐positive cells that are A‐22‐negative. The cells are connected to small veins and to the surface of the spinal cord. Immunopositive cells are generally homogeneous in size and shape and are found not only in the spinal cord but also in several areas of the brain. These results indicate that the stained cell is an astrocyte. Most of these cells (88%) are distributed in the gray matter of the spinal cord; the remainder (12%) are found in the white matter. Most of the cells in the gray matter are found in the ventral and dorsal horns, but some are also present in the central area along the ventricle. Glial cell bodies form an array along the longitudinal axis and are connected to each other by thick projections. The cellular array is not visible in coronal sections. In contrast, thin processes from the cells extend to the surfaces of veins, to neurons, and to the periphery of the spinal cord. We estimate that there are about 13,500 A‐22‐positive astrocytes in the spinal cord; however, this represents only 26% of the total number of astrocytes in the spinal cord (∼52,000). GLIA 36:406–413, 2001. © 2001 Wiley‐Liss, Inc.
Predictors of institutionalization of cognitively‐impaired elderly cared for by their relatives
Authors: Spruytte Nele , Van Audenhove Chantal , Lammertyn Frans
Published: August 2002

Objectives

The purpose of this study is to identify risk factors for nursing home placement of cognitively‐impaired elderly, with special attention to the role of psychosocial factors such as the caregiver's preference for institutionalization and the quality of the dyadic relationship.

Methods

Partners, children and children‐in‐law caring for a relative suffering from dementia (n = 144) were interviewed at home. Sociodemographic variables, patient characteristics, characteristics of the caregiving situation, caregiver characteristics, the support with care and the quality of the caregiving relationship are included as predictors of the caregiver's preference for institutionalization and of the actual institutionalization six to nine months later. Data are analyzed using multiple (logistic) regression analyses.

Results

The hypothesis that a poor quality of the relationship, besides other determinants, will be predictive of institutionalization received partial support. No relationship is found between the premorbid relationship quality and institutionalization (preference and actual). However, a good current relationship between the caregiver and the patient reduced the risk of nursing home placement. Institutionalization rate was 16.5% and it was predicted by the caregiver's preference for institutionalization, the functional level of the patient, the quality of the current relationship and the performance of accommodation changes at home.

Conclusion

Research and interventions directed at delaying or preventing institutionalization should pay more attention to the role of psychosocial aspects in the process of nursing home placement. Specifically the relationship quality in terms of criticism or warmth might be a critical factor in the continuation of home care. Copyright © 2001 John Wiley & Sons, Ltd.
Sensory system interactions during simultaneous vestibular and visual stimulation in PET
Authors: Deutschländer Angela , Bense Sandra , Stephan Thomas , Schwaiger Markus , Brandt Thomas , Dieterich Marianne
Published: August 2002

The patterns of regional cerebral blood flow (rCBF) increases and decreases in PET were compared for unimodal vestibular, unimodal visual, and for simultaneous vestibular and visual stimulation. Thirteen healthy volunteers were exposed to a) caloric vestibular stimulation, b) small‐field visual motion stimulation in roll, c) simultaneous caloric vestibular and visual pattern stimulation. Unimodal vestibular stimulation led to activations of vestibular cortex areas, in particular the parieto‐insular vestibular cortex (PIVC), and concurrent deactivations of visual cortical areas [Brodmann area (BA) 17–19]. Unimodal visual motion stimulation led to activations of the striate visual cortex and the motion‐sensitive area in the middle temporal/middle occipital gyri (BA 19/37) with concurrent deactivations in the PIVC. Simultaneous bimodal stimulation resulted in activations of the cortical representation of both sensory modalities. In the latter condition activations and deactivations were significantly smaller compared to unimodal stimulation. The findings are consistent with the concept of an inhibitory reciprocal vestibulo‐visual interaction in all three stimulus conditions. Hum. Brain Mapping 16:92–103, 2002. © 2002 Wiley‐Liss, Inc.
Frequency dependence and gender effects in visual cortical regions involved in temporal frequency dependent pattern processing
Authors: Kaufmann Christian , Elbel Gregor‐Konstantin , Gössl Christoff , Pütz Benno , Auer Dorothee P.
Published: August 2002

Neural response to flickering stimuli has been shown to be frequency dependent in the primary visual cortex. Controversial gender differences in blood oxygen level dependent (BOLD) amplitude upon 6 and 8 Hz visual stimulation have been reported. In order to analyze frequency and gender effects in early visual processing we employed a passive graded task paradigm with a dartboard stimulus combining eight temporal frequencies from 0 to 22 Hz in one run. Activation maps were calculated within Statistical Parametric Mapping, and BOLD amplitudes were estimated for each frequency within the striate and extrastriate visual cortex. The BOLD amplitude was found to steadily rise up to 8 Hz in BA 17 and 18 with an activation plateau at higher frequencies. In addition, we observed a laterality effect in the striate cortex with higher BOLD contrasts in the right hemisphere in men and in women. BOLD response rises similarly in men and women up to 8 Hz but with lower amplitudes in women at 4, 8, and 12 Hz (30% lower). No frequency effect above 1 Hz was found in the extrastriate visual cortex. There was also a regional specific gender difference. Men activated more in the right lingual gyrus (BA 18) and the right cerebellum compared with women, whereas women showed more activation in the right inferior temporal gyrus (BA 17). The study indicates that frequency dependent processing at the cortical level is limited to the striate cortex and may be associated with a more global information processing (right hemisphere dominance), particularly in men. The finding of significantly lower BOLD amplitudes in women despite previously shown larger VEP (visual evoked potential) amplitudes might suggest gender differences in cerebral hemodynamics (baseline rCBV, rCBF, or neurovascular coupling). The regional distinction points at additional differences in psychological processing even when using a simple visual stimulus. Hum. Brain Mapping 14:28–38, 2001. © 2001 Wiley‐Liss, Inc.
Quantitative structure–property relationships in the pyridine series
Authors: Pankratov Alexei N.
Published: August 2002

By means of the MNDO, AM1, and PM3 methods, standard heats of formation, entropies, ionization potentials, and molecular dipole moments of the pyridine series compounds have been computed. The information on the experimental values of the above quantities has been systematized. Linear dependencies allowing a priori evaluation of thermodynamic and molecular characteristics of pyridines have been stated. Correlations of the 2,2′‐bipyridines pKa values for aqueous solutions with the gaseous‐phase proton affinities have been found. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:229–241, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10013
Asymmetric synthesis of epoxides from aromatic aldehydes and benzyl halides catalyzed by C2 symmetric optically active sulfides having a binaphthyl skeleton
Authors: Miyake Yoshihiro , Oyamada Arihiro , Nishibayashi Yoshiaki , Uemura Sakae
Published: August 2002

Reactions of aromatic aldehydes with benzyl bromide or iodide in the presence of a catalytic amount (10 mol%) of a C2 symmetric sulfide having a binaphthyl skeleton afford the corresponding trans‐stilbene oxides in moderate to good yields with moderate enantioselectivities (up to 55% enantiomeric excess). The addition of tetra‐n‐butylammonium iodide to the catalytic reaction system much improves the yield of the epoxides. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:270–275, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10028
Diisothiocyanates as heterodienophiles or dipolarophiles in the presence of α‐thioxothioamides or mesoionic thiazoles
Authors: Morel Georges , Marchand Evelyne
Published: August 2002

Reactions of α‐thioxothioamides (1) with diisothiocyanates were carried out in the hope of generating the N,N′‐bis(1,3‐thiazoline‐2‐thiones) (A). Although that purpose could not be achieved, we succeeded in preparing the monocycloadducts 7 from the phenylene‐1,2‐diisothiocyanate (4). The benzimidazole derivatives 8 and 9 were also characterized and a mechanism was assumed to account for this intramolecular process. On the other hand, the regioselective synthesis of the N,N′‐biimidazole (13) containing the phenylene bridge was performed by the treatment of the 5‐aminothiazolium chloride (2) with the diisothiocyanate (4) in a basic medium. The mesoionic derivative 13 probably arises from the monoimidazolium‐4‐thiolate (12) which was shown to react with the salt 2 under similar conditions to give the primary cycloadduct 14 as an intermediate towards the bis(imidazolium) (13). © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:617–624, 2001
How reliable are hospital efficiency estimates? Exploiting the dual to homothetic production
Authors: Folland Sherman T. , Hofler Richard A.
Published: August 2002

For scientific use, stochastic frontier estimates of hospital efficiency must be robust to plausible departures from the assumptions made by the investigator. Comparisons of alternative study designs, each well within the ‘accepted’ range according to current practice, generate similar mean inefficiencies but substantially different hospital rankings. The three alternative study contrasts feature (1) pooling vs partitioned estimates, (2) a cost function dual to a homothetic production process vs the translog, and (3) two conceptually valid but empirically different cost‐of‐capital measures. The results suggest caution regarding the use of frontier methods to rank individual hospitals, a use that seems to be required for reimbursement incentives, but they are robust when generating comparisons of hospital group mean inefficiencies, such as testing models that compare non‐profits and for‐profits by economic inefficiency. Demonstrations find little or no efficiency differences between these paired groups: non‐profit vs for‐profit; teaching vs non‐teaching; urban vs rural; high percent of Medicare reliant vs low percent; and chain vs independent hospitals. Copyright © 2001 John Wiley & Sons, Ltd.
Evaluating the donor site after harvest of free jejunum grafts
Authors: Uchiyama Kiyotaka , Kimata Yoshihiro , Ebihara Satoshi , Nakatsuka Takashi , Harii Kiyonori
Published: August 2002

Background

Free jejunal grafts are commonly used for reconstruction after surgery for hypopharyngeal and cervical esophageal cancer. However, few reports have addressed postoperative morbidity at the abdominal donor site.

Methods

Preoperative morbidity and postoperative complications were analyzed in 126 patients in whom free jejunal grafts had been harvested from 1992 through 1996.

Results

Although 27 patients had previously undergone abdominal surgery, there was no correlation between previous abdominal surgery and abdominal complications after graft harvest (p > .25). Abdominal complications were not correlated with patient age (p > .25).

Conclusions

Our findings suggest that previous abdominal surgery (except on the ileum) and patient age are not contraindications to free jejunal graft harvest. © 2002 Wiley Periodicals, Inc.
Phase precession and phase‐locking of hippocampal pyramidal cells
Authors: Bose Amitabha , Recce Michael
Published: August 2002

We propose that the activity patterns of CA3 hippocampal pyramidal cells in freely running rats can be described as a temporal phenomenon, where the timing of bursts is modulated by the animal's running speed. With this hypothesis, we explain why pyramidal cells fire in specific spatial locations, and how place cells phase‐precess with respect to the EEG theta rhythm for rats running on linear tracks. We are also able to explain why wheel cells phase‐lock with respect to the theta rhythm for rats running in a wheel. Using biophysically minimal models of neurons, we show how the same network of neurons displays these activity patterns. The different rhythms are the result of inhibition being used in different ways by the system. The inhibition is produced by anatomically and physiologically diverse types of interneurons, whose role in controlling the firing patterns of hippocampal cells we analyze. Each firing pattern is characterized by a different set of functional relationships between network elements. Our analysis suggests a way to understand these functional relationships and transitions between them. Hippocampus 2001;11:204–215. © 2001 Wiley‐Liss, Inc.
The demand for child curative care in two rural thanas of Bangladesh: effect of income and women's employment
Authors: Levin Ann , Rahman M. A. , Quayyum Zahidul , Routh Subrata , Barkat‐e‐Khuda
Published: August 2002

This paper seeks to investigate the determinants of child health care seeking behaviours in rural Bangladesh. In particular, the effects of income, women's access to income, and the prices of obtaining child health care are examined. Data on the use of child curative care were collected in two rural areas of Bangladesh—Abhoynagar Thana of Jessore District and Mirsarai Thana of Chittagong District—in March 1997. In estimating the use of child curative care, the nested multinomial logit specification was used.

The results of the analysis indicate that a woman's involvement in a credit union or income generation affected the likelihood that curative child care was used. Household wealth decreased the likelihood that the child had an illness episode and affected the likelihood that curative child care was sought. Among facility characteristics, travel time was statistically significant and was negatively associated with the use of a provider. Copyright © 2001 John Wiley & Sons, Ltd.
Hold the Line: An Examination of Line vs. Staff Differences
Authors: Church Allan H. , Waclawski Janine
Published: August 2002

Despite common perceptions about the differences between line and staff personnel, few studies have provided answers as to which group is more effective. This study explores in detail key differences in managerial strengths between 46 line managers and 52 staff professionals in one of the fastest growing, highly service‐oriented retail organizations in the United States. Using behavioral data from a developmental multirater feedback effort, results suggest that staff personnel were more modest and accurate in their self‐assessments, while line managers were more service‐oriented but significantly weaker at relationships, openness to new ideas, demonstrating respect, and adaptability to change. © 2001 John Wiley & Sons, Inc.
The influence of three months of methylphenidate treatment on platelet‐poor plasma biogenic amine levels in boys with attention deficit hyperactivity disorder
Authors: Spivak B. , Vered Y. , Yoran‐Hegesh R. , Graff E. , Averbuch E. , Vinokurow S. , Weizman A. , Mester R.
Published: August 2002

Attention deficit hyperactivity disorder (ADHD) is related to dysregulation in the activity of brain monoamines. The aim of the present study was to assess the impact of three months' methylphenidate (MPH) treatment on platelet‐poor plasma (PPP) norepinephrine (NE), dopa and serotonin (5‐HT) levels as well as on ADHD symptomatology. Three months of MPH treatment in 16 ADHD boys, aged 11.4 ± 1.6 years, resulted in a significant reduction in PPP NE levels (p < 0.05). A tendency towards a reduction of PPP 5‐HT and dopa levels was detected (p < 0.1 for both). The decrease in PPP biogenic amine levels after three months of MPH treatment was accompanied by a significant reduction in all psychometric characteristics of ADHD. This result indicates the possible role of overactivity of the noradrenergic system in the pathophysiology of ADHD and suggests that the MPH therapeutic action may be related to stimulant‐induced inhibitory effect on the noradrenergic system. Copyright © 2001 John Wiley & Sons, Ltd.
Sources of stream sulphate in headwater catchments in Otter Creek Wilderness, West Virginia, USA
Authors: Fitzhugh Ross D. , Furman Tanya , Korsak Andrea K.
Published: August 2002

Upland forested catchments in the Appalachian Plateau region receive among the greatest rates of atmospheric sulphur (S) deposition in the eastern USA, although coal mines and S‐bearing minerals in bedrock may also contribute to stream acidity in this region. Watershed mass balance and stable S isotopic values (δ34S) of sulphate (SO42−) were used to assess the contributions to stream SO42− from atmospheric and lithogenic sources at Yellow Creek (YC), a headwater catchment on the Appalachian Plateau in West Virginia. Oxygen isotopic values (δ18O) of water were used to study catchment hydrology. Stream output of SO42− was c. 60% of atmospheric S deposition during a relatively dry year, whereas atmospheric S input was nearly balanced by stream output during a year with above normal amounts of precipitation. The temporal patterns and values of δ34S were similar between bulk precipitation and stream water at two upper elevation sites. At the lowest elevation site, stream δ34S values were similar to bulk precipitation values during the dormant season but were slightly lower than precipitation during the low‐flow summer, probably as the result of a greater proportion of stream water being derived from deep hydrological flowpaths that have contacted S‐bearing minerals with low δ34S values in coal seams. Stream δ34S values at YC were significantly higher than at Coal Run, a catchment containing abandoned coal prospects and having a greater amount of S‐bearing minerals than YC. Results suggested that lithogenic S is a relatively minor source and that atmospheric deposition is the principal source of stream SO42−, and thus stream acidity, at YC. Copyright © 2001 John Wiley & Sons, Ltd.
The role of overland flow and subsurface flow on the spatial distribution of soil moisture in the topsoil
Authors: van Asch Th. W. J. , van Dijck S. J. E. , Hendriks M. R.
Published: August 2002

Many investigations show relationships between topographical factors and the spatial distribution of soil moisture in catchments. However, few quantitative analyses have been carried out to elucidate the role of different hydrological processes in the spatial distribution of topsoil moisture in catchments. A spatially distributed rainfall—runoff model was used to investigate contributions of subsurface matric flow, macropore flow and surface runoff to the spatial distribution of soil moisture in a cultivated catchment. The model results show that lateral subsurface flow in the soil matrix or in macropores has a minor effect on the spatial distribution of soil moisture. Only when a perched groundwater table is maintained long enough, which is only possible if the subsurface is completely impermeable, may a spatial distribution in moisture content occur along the slope. Surface runoff, producing accumulations of soil moisture in flat flow paths of agricultural origin (field boundaries), was demonstrated to cause significant spatial variations in soil moisture within a short period after rainfall (<2 days). When significant amounts of surface runoff are produced, wetter moisture conditions will be generated at locations with larger upstream contributing areas. Copyright © 2001 John Wiley & Sons, Ltd.
On constraining TOPMODEL hydrograph simulations using partial saturated area information
Authors: Blazkova S. , Beven K. J. , Kulasova A.
Published: August 2002

This study uses field observations of the extent of saturated area over limited areas of the small Uhlirska catchment (1·87 km2) in the Czech Republic in calibrating the parameters of a version of TOPMODEL. The field information is used within the GLUE methodology, which involves evaluating many different randomly chosen parameter sets within the chosen model structure. The different parameter sets are evaluated on performance in both discharge prediction and prediction of the observed saturated areas using appropriate likelihood measures. The results show that the saturated area information results in a strong constraint of the transmissivity parameter of the model, but that the other parameters show good fits across most of the range over which they are sampled. Quite different posterior distributions for the transmissivity parameter are found for the two different years of data used in conditioning the model. The effect on the prediction bounds for stream discharges is much less, perhaps because the transmissivity parameter combines with different values of the other parameters in the two years to capture the dominant modes of discharge response of the catchment. Copyright © 2002 John Wiley & Sons, Ltd.
Aspects of river ice hydrology in Japan
Authors: Hirayama Kenichi , Yamazaki Makoto , Tao Shen Hung
Published: August 2002

Rivers in northern Japan are subjected to ice formation each winter. They are typically very steep with rapid changes in channel slope. As a result, ice covers are usually discontinuous with open water sections. Winter discharges in Japanese rivers are usually very small. Water temperature and ice production in these streams are very sensitive to the change in air temperature. The open water sections enable the formation of frazil and anchor ice during the winter. Owing to the relatively stable winter weather and heavy snow cover, premature break‐up and ice jams rarely occur, even though the channel geometry of these rivers is favourable for their occurrence. In this paper, hydrometeorological factors related to ice‐cover formation, frazil and anchor‐ice development, and ice‐jam formation, as well as measurements of the undercover discharge in rivers in northern Japan are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Quantitative evaluation of oxidative stress, chronic inflammatory indices and leptin in cancer patients: Correlation with stage and performance status
Authors: Mantovani Giovanni , Macciò Antonio , Madeddu Clelia , Mura Loredana , Gramignano Giulia , Lusso Maria Rita , Mulas Carlo , Mudu Maria Caterina , Murgia Viviana , Camboni Paolo , Massa Elena , Ferreli Luca , Contu Paolo , Rinaldi Augusto , Sanjust Enrico , Atzei Davide , Elsener Bernhard
Published: August 2002

In advanced cancer patients, the oxidative stress could take place either at the onset of disease or as a function of disease progression. To test this hypothesis, the following parameters were investigated: the erythrocyte activity of the enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), the serum activity of glutathione reductase (GR) and the serum total antioxidant status (TAS). The total antioxidant capacity of plasma LMWA was evaluated by the cyclic voltammetry methodology. We further determined the serum levels of proinflammatory cytokines (IL‐6 and TNFα), IL‐2, leptin and C‐reactive protein (CRP). All of these parameters have been correlated with the most important clinical indices of patients such as Stage of disease, ECOG PS and clinical response. Eighty‐two advanced stage cancer patients and 36 healthy individuals used as controls were included in the study. Our findings show that SOD activity was significantly higher in cancer patients than in controls and GPx activity was significantly lower in cancer patients than in controls. Serum values of IL‐6, TNFα and CRP were significantly higher in patients than in controls. Serum leptin values of cancer patients were significantly lower than controls. SOD activity increased significantly from Stage II/ECOG 0‐1 to Stage IV/ECOG 0–1, whereas it decreased significantly in Stage IV/ECOG 3. GPx activity decreased significantly in Stage IV/ECOG 2–3. An inverse correlation between ECOG PS and serum leptin levels was found. Serum levels of IL‐2 decreased from Stage II/ECOG 0–1 to Stage IV/ECOG 2–3. A direct correlation between Stage/ECOG PS and serum levels of both IL‐6 and CRP was observed. Cisplatin administration induced a significant increase of GPx after 24 hr. In conclusion, this is the first study that shows that several “biological” parameters of cancer patients such as antioxidant enzyme activity, cytokines, leptin and CRP strictly correlate with the most important clinical parameters of disease such as Stage and ECOG PS. © 2001 Wiley‐Liss, Inc.
Expression profiling of MMA‐1a and splice variant MMA‐1b: New cancer/testis antigens identified in human melanoma
Authors: de Wit Nicole J.W. , Weidle Ulrich H. , Ruiter Dirk J. , van Muijen Goos N.P.
Published: August 2002

Using high‐density oligonucleotide array analysis, we have recently compared the gene expression profiles of 2 human melanoma cell lines with marked difference in metastatic behavior after subcutaneous inoculation into nude mice (de Wit et al., Melanoma Res, in press). We identified an expressed sequence tag (EST), which we called malignant melanoma‐associated 1 (MMA‐1a), showing evident differential expression between the 2 cell lines. The MMA‐1a gene is localized on chromosome 21q22.2 and its mRNA exists of 4 exons. Homology search displayed a splice variant of MMA‐1a that lacks exon 3 and that was called MMA‐1b. Expression profiles of MMA‐1a and MMA‐1b are determined by reverse transciptase polymerase chain reaction (RT‐PCR) analysis. Among 30 different normal tissue samples, expression of MMA‐1a and MMA‐1b was exclusively found in the testis after a first PCR of 30 cycles. Even more sensitive screening achieved by performing multiple semi‐nested RT‐PCR showed no or very low expression in the other normal tissues tested. During melanocytic tumor progression, MMA‐1a and/or MMA‐1b exhibited an emergence of expression in primary melanoma (20%) and melanoma metastasis samples (30%) after only 1 round of PCR. Expression of MMA‐1a and/or MMA‐1b was also identified in other tumor cell lines and fresh tumor samples of variable origin, e.g., lung, liver, bladder and soft tissues (sarcomas). We conclude that MMA‐1a and MMA‐1b are new members of the family of cancer/testis antigens. © 2002 Wiley‐Liss, Inc.
Comparison of the effects of EM‐652 (SCH57068), tamoxifen, toremifene, droloxifene, idoxifene, GW‐5638 and raloxifene on the growth of human ZR‐75‐1 breast tumors in nude mice
Authors: Gutman Matthieu , Couillard Steeve , Roy Jenny , Labrie Fernand , Candas Bernard , Labrie Claude
Published: August 2002

EM‐652 exerts pure antiestrogenic activity in the mammary gland and endometrium, while tamoxifen, the antiestrogen most widely used for the treatment of breast cancer, exerts mixed antiestrogenic–estrogenic activity in these tissues. Our objective was to compare the agonistic and antagonistic effects of EM‐652 with tamoxifen and 5 other antiestrogens on the growth of ZR‐75‐1 human breast xenografts in ovariectomized nude mice. During the 23 weeks of treatment at a daily oral dose of 50 μg, EM‐652 was the only compound that decreased tumor size relative to pretreatment values, whereas the 6 other antiestrogens only decreased to various extents the progression rate stimulated by estrone. Under estrone stimulation, all groups of animals had more than 60% of their tumors in the progression category except for the EM‐652–treated group, where only 7% of the tumors progressed. In the absence of estrone stimulation, progression was seen in 60%, 33%, 21% and 12% of tumors in the tamoxifen‐, idoxifene‐, toremifene‐ and raloxifene‐treated groups, respectively, while only 4% of tumors progressed in the EM‐652–treated group. The agonistic and antagonistic actions of each antiestrogen were also measured on endometrial epithelial cell thickness. Our present findings indicate that EM‐652, in addition to being the most potent antiestrogen on human breast tumor growth, has no agonistic effect in breast and endometrial tissues. Since previous data have shown benefits of EM‐652 on bone density and lipid profile, this compound could be an ideal candidate for chemoprevention of breast and uterine cancers, while protecting against osteoporosis and cardiovascular disease. © 2002 Wiley‐Liss, Inc.
Population‐based survival analysis of colorectal cancer patients in Singapore, 1968–1992
Authors: Du Wen‐Bo , Chia Kee‐Seng , Sankaranarayanan Rengaswamy , Sankila Risto , Seow Adeline , Lee Hin‐Peng
Published: August 2002

Since the 1980s, colorectal cancer incidence in Singapore has ranked second to lung in males and females. We describe a population‐based analysis of survival of colorectal cancer patients diagnosed from 1968 to 1992 in Singapore. Data of colorectal cancer patients diagnosed during 1968–1992 were retrieved from the Singapore Cancer Registry. Patients were passively followed up for death to the end of 1997. The final dataset consisted of 10,114 subjects. Observed and relative survival rates were calculated by stage (localized, regional metastases and distant metastases), age, ethnicity and calendar period for both genders. Over the study period, a significant progress in survival of colorectal cancer patients was observed. For localized cancer of the colon, the 5‐year age‐standardized relative survival (ASRS) increased from 36% in 1968–1972 to 66% in 1988–1992 for males and from 32 to 71% for females. For localized rectal cancer, the 5‐year ASRS improved from 25 to 66% for males and from 23 to 66% in females. Similarly, improvement was observed in colorectal cancer patients with regional metastases, but not in those with distant metastases. Calendar year period and clinical stage of disease were identified as major significant prognostic factors of survival for colorectal cancer. The substantially improved colorectal cancer survival rates reflected the interplay of cancer control activities in various areas, such as health promotion, early diagnosis and treatment. Our study shows a unique changing pattern of survival experience for colorectal patients from a country undergoing rapid economic development. © 2002 Wiley‐Liss, Inc.
Inhibitory effects of a luteinizing hormone‐releasing hormone agonist on basal and epidermal growth factor‐induced cell proliferation and metastasis‐associated properties in human epidermoid carcinoma a431 cells
Authors: Huang Ying‐tang , Hwang Jiuan‐jiuan , Lee Lung‐ta , Liebow Charles , Lee Ping‐ping H. , Ke Ferng‐chun , Lo Tung‐bin , Schally Andrew V. , Lee Ming‐ting
Published: August 2002

The purpose of this study was to investigate the effects of a potent LHRH agonist, [D‐Trp6]LHRH on the basal and EGF‐induced cell proliferation and the metastasis‐associated properties in A431 human epidermoid carcinoma. [D‐Trp6]LHRH time‐dependently inhibited the basal and EGF‐stimulated growth of A431 cancer cells. It is assumed that phosphorylation/dephosphorylation of cellular proteins is highly related to cell growth. This study demonstrates that [D‐Trp6]LHRH decreased the basal and EGF‐induced total cellular kinase activity, particularly the tyrosine phosphorylation of several cellular proteins including the EGFR. In contrast, [D‐Trp6]LHRH did not cause detectable changes in basal and EGF‐stimulated serine/threonine phosphorylation of A431 cellular proteins. The inhibitory effect of [D‐Trp6]LHRH on A431 cell proliferation was associated with apoptosis as evidenced by the cell morphology and DNA integrity (ladder pattern), the expression of interleukin 1β‐converting enzyme (ICE) and activation of caspase. Furthermore, EGF could rescue the remaining attached A431 cells following [D‐Trp6]LHRH treatment for 48 hr, which suggests that limited exposure to [D‐Trp6]LHRH did not channel all cells to irreversible apoptotic process. We also determined the effects of [D‐Trp6]LHRH on metastasis‐associated properties in A431 cells. [D‐Trp6]LHRH reduced both basal and EGF‐stimulated secretion of MMP‐9 and MMP‐2. In addition, [D‐Trp6]LHRH suppressed the basal and EGF‐induced invasive activity of A431 cells based on an in vitro invasion assay. In conclusion, this study indicates that [D‐Trp6]LHRH may act partly through activating tyrosine phosphatase activity to inhibit cell proliferation and the metastasis‐associated properties of A431 cancer cells. Our work suggests that [D‐Trp6]LHRH may be therapeutically useful in limiting the tumor growth and metastasis of some neoplasms. © 2002 Wiley‐Liss, Inc.