bluuebunny/crossref_metadata_2025 huggingface dataset:
Schwann cell myelination occurred without basal lamina formation in laminin α2 chain‐null mutant (dy3K/dy3K) mice
Authors: Nakagawa Masahiro , Miyagoe‐Suzuki Yuko , Ikezoe Koji , Miyata Yuhei , Nonaka Ikuya , Harii Kiyonori , Takeda Shin'Ichi
Published: September 2002

The laminin α2 chain is a major component of basal lamina in both skeletal muscle and the peripheral nervous system. Laminin α2 chain deficiency causes merosin‐deficient congenital muscular dystrophy, which affects not only skeletal muscles, but also the peripheral and central nervous systems. It has been reported that the formation of basal lamina is required for myelination in the peripheral nervous system. In fact, the spinal root of dystrophic mice (dy/dy mice), whose laminin α2 chain expression is greatly reduced, shows lack of basal lamina and clusters of naked axons. To investigate the role of laminin α2 chain and basal lamina in vivo, we examined the peripheral nervous system of dy3K/dy3Kmice, which are null mutants of laminin α2 chain. The results indicate the presence of myelination although Schwann cells lacked basal lamina in the spinal roots of dy3K/dy3K mice, suggesting that basal lamina is not an absolute requirement for myelination in vivo. Immunohistochemically, the expression of laminin α4 chain was increased and laminin α5 chain was preserved in the endoneurium of the spinal root. Laminin α4 and α5 chains may play the critical role in myelination instead of laminin α2 chain in dy3K/dy3Kmice. In addition, the motor conduction velocity of the sciatic nerve was significantly reduced compared with that of wild‐type littermate. This reduction in conduction velocity may be due to small axon diameter, thin myelin sheath and the patchy disruption of the basal lamina of the nodes of Ranvier in dy3K/dy3Kmice. GLIA 35:101–110, 2001. © 2001 Wiley‐Liss, Inc.
Development and validation of the Observation List for early signs of Dementia (OLD)
Authors: Hopman‐Rock Marijke , Tak Erwin C. P. M. , Staats Patricia G. M.
Published: September 2002

Objective

Development and validation of a short Observation List of possible early signs of Dementia (OLD) for use in general practice.

Design

Stepwise development using reviews of publications and expert consensus. Field study for evaluation of reliability. Validation study (interviews, family forms) using existing valid and reliable measures. Use of data reduction techniques to construct a short version.

Setting of field study

Twenty‐two GPs in 19 Dutch practices.

Participants

The first two patients seen on 15 working days (n = 470) were observed. Inclusion: age > 75, without a known diagnosis of dementia. Exclusion: psychiatric treatment, severe depression, acute illness with confusion. Division of patients into three groups with no, intermediate, and the most signs (total of interviewed patients, n = 60; family forms, n = 39).

Outcome measures

Reliability (Cronbach's alpha and factor‐analysis). Convergent validity using the Cognitive Screening Test (CST), the Word Learning Test (WLT, total and retention), the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), the Groningen Activities Restriction Scale (GARS), and an IADL scale. Discriminant validity using the geriatric depression scale (GDS). Construct validity using a Principal Component Analysis (PRINCALS). Incremental validity using the intuitive opinion of the GP (McNemar test).

Results

Reliability in the total group 0.88, first factor explained variance 42.5%. Convergent validity (two‐way ANOVA) results: CST (p = 0.00), WLT‐total (p = 0.001), WLT retention (p = 0.00), IQCODE (p = 0.09). No statistically significant differences for GARS and IADL. GDS (p = 0.30) not different. PRINCALS first factor explained 48% of variance. The OLD added to the GP opinion (McNemar p = 0.00). Reliability short version 0.89 (interviewed group), 0.86 (total group).

Conclusions

The OLD is a valid and reliable method to detect early signs of dementia in general practice that can indicate when it may be useful to employ existing screening instruments. Copyright © 2001 John Wiley & Sons, Ltd.
Pharmacotherapy of Alzheimer's disease: is there a need to redefine treatment success?
Authors: Winblad Bengt , Brodaty Henry , Gauthier Serge , Morris John C , Orgogozo Jean‐Marc , Rockwood Kenneth , Schneider Lon , Takeda Masatoshi , Tariot Pierre , Wilkinson David
Published: September 2002

The traditional aim of Alzheimer's disease treatment in clinical trials has been to improve cognitive abilities. It has become increasingly clear, however, that other aspects are important in assessing treatment responses. A group of 10 physicians recently gathered to review the current criteria for assessing treatment success in Alzheimer's disease. While cognition has been previously viewed as the primary measure of efficacy, areas such as functional abilities, behaviour, caregiver burden, quality of life and resource utilization all need to be comprehensively assessed to fully evaluate treatment effects in patients with Alzheimer's disease, as well as their impacts on caregivers and society. Postponing or slowing decline in any of these areas may represent an important benefit and should be considered as an outcome measure in clinical trials, clinical practice and decision‐making about healthcare budgets. Accepted instruments are available for assessing outcomes in each aspect of Alzheimer's disease, but they need to be selected carefully to provide valid, meaningful data. Some of the most frequently used outcome measures in Alzheimer's disease are reviewed. Using expanded criteria for treatment success and clinically relevant outcome measures, data from currently available studies show that cholinesterase inhibitors produce clinically meaningful long‐term benefits in multiple domains in patients with Alzheimer's disease. Copyright © 2001 John Wiley & Sons, Ltd.
Stochastic league tables: communicating cost‐effectiveness results to decision‐makers
Authors: Hutubessy Raymond C.W. , Baltussen Rob M.P.M. , Evans David B. , Barendregt Jan J. , Murray Christopher J.L.
Published: September 2002

The presentation of the results of uncertainty analysis in cost‐effectiveness analysis (CEA) in the literature has been relatively academic with little attention paid to the question of how decision‐makers should interpret the information particularly when confidence intervals overlap. This question is especially relevant to sectoral CEA providing information on the costs and effects of a wide range of interventions.

This paper introduces stochastic league tables to inform decision‐makers about the probability that a specific intervention would be included in the optimal mix of interventions for various levels of resource availability, taking into account the uncertainty surrounding costs and effectiveness. This information helps decision‐makers decide on the relative attractiveness of different intervention mixes, and also on the implications for trading gains in efficiency for gains in other goals such as reducing health inequalities and increasing health system responsiveness. Copyright © 2001 John Wiley & Sons, Ltd.
Stereological estimates of number and length of capillaries in subdivisions of the human hippocampal region
Authors: Løkkegaard Annemette , Nyengaard Jens R. , West Mark J.
Published: September 2002

The hippocampal formation is a neuroanatomically well‐defined region of the brain involved in memory processes. In view of the functional importance of the region and its involvement in a number of brain pathologies, including Alzheimer's disease and temporal lobe epilepsy, a quantitative description of its vascular supply represents an important first step in evaluating the involvement of vascular changes in these phenomena. Unbiased estimates of the length and connectivity of the vascular supply of brain regions have not been described previously. The total number, total length, and distribution of the diameters of capillaries were estimated in the five major subdivisions of the hippocampal formation (fascia dentata, hilus, CA3‐2, CA1, and subiculum) in 5 normal males, 52–84 years of age. These estimates were used to derive several other structural parameters. Both the primary and the derived parameters were used to make inter‐ and intra‐individual comparisons. For each of the five major subdivisions from each individual, the volume was estimated using the Cavalieri principle. The total capillary length was estimated on 3‐μm‐thick plastic isotropic uniform random sections. Using a topological definition of a capillary unit and the optical disector, total capillary number was estimated in 40‐μm‐thick plastic sections. Length‐ and number‐weighted three‐dimensional diameter distributions were obtained from the thin and thick plastic sections, respectively. In each subdivision the total length of capillaries was correlated with previously obtained data on the number of neurons in the same subdivisions of the same individuals. Intersubdivisional differences were observed, in that the hilus of the dentate gyrus had fewer capillaries per unit volume than the other four subdivisions. Interindividual comparisons indicate that the interindividual variances are of a magnitude suitable for sensitive group comparisons. The design‐based stereological methods that were used in the analyses can provide a basis for a new unbiased approach to the estimation of vascular parameters in well‐defined regions of the brain. Hippocampus 2001;11:726–740. © 2001 Wiley‐Liss, Inc.
Optimal estimation of suspended‐sediment concentrations in streams
Authors: Holtschlag David J.
Published: September 2002

Optimal estimators are developed for computation of suspended‐sediment concentrations in streams. The estimators are a function of parameters, computed by use of generalized least squares, which simultaneously account for effects of streamflow, seasonal variations in average sediment concentrations, a dynamic error component, and the uncertainty in concentration measurements. The parameters are used in a Kalman filter for on‐line estimation and an associated smoother for off‐line estimation of suspended‐sediment concentrations. The accuracies of the optimal estimators are compared with alternative time‐averaging interpolators and flow‐weighting regression estimators by use of long‐term daily‐mean suspended‐sediment concentration and streamflow data from 10 sites within the United States. For sampling intervals from 3 to 48 days, the standard errors of on‐line and off‐line optimal estimators ranged from 52·7 to 107%, and from 39·5 to 93·0%, respectively. The corresponding standard errors of linear and cubic‐spline interpolators ranged from 48·8 to 158%, and from 50·6 to 176%, respectively. The standard errors of simple and multiple regression estimators, which did not vary with the sampling interval, were 124 and 105%, respectively. Thus, the optimal off‐line estimator (Kalman smoother) had the lowest error characteristics of those evaluated. Because suspended‐sediment concentrations are typically measured at less than 3‐day intervals, use of optimal estimators will likely result in significant improvements in the accuracy of continuous suspended‐sediment concentration records. Additional research on the integration of direct suspended‐sediment concentration measurements and optimal estimators applied at hourly or shorter intervals is needed. Published in 2001 by John Wiley & Sons, Ltd.
Simulation of stream discharge and transport of nitrate and selected herbicides in the Mississippi River Basin
Authors: Broshears Robert E. , Clark Gregory M. , Jobson Harvey E.
Published: September 2002

Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO; Ohio River at Grand Chain, IL; and Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992–1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico. Published in 2001 by John Wiley & Sons, Ltd.
Annual suspended sediment and trace element fluxes in the Mississippi, Columbia, Colorado, and Rio Grande drainage basins
Authors: Horowitz Arthur J. , Elrick Kent A. , Smith James J.
Published: September 2002

Suspended sediment, sediment‐associated, total trace element, phosphorus (P), and total organic carbon (TOC) fluxes were determined for the Mississippi, Columbia, Rio Grande, and Colorado Basins for the study period (the 1996, 1997, and 1998 water years) as part of the US Geological Survey's redesigned National Stream Quality Accounting Network (NASQAN) programme. The majority (≥70%) of Cu, Zn, Cr, Ni, Ba, P, As, Fe, Mn, and Al are transported in association with suspended sediment; Sr transport seems dominated by the dissolved phase, whereas the transport of Li and TOC seems to be divided equally between both phases. Average dissolved trace element levels are markedly lower than reported during the original NASQAN programme; this seems due to the use of ‘clean’ sampling, processing, and analytical techniques rather than to improvements in water quality. Partitioning between sediment and water for Ag, Pb, Cd, Cr, Co, V, Be, As, Sb, Hg, and Ti could not be estimated due to a lack of detectable dissolved concentrations in most samples.

Elevated suspended sediment‐associated Zn levels were detected in the Ohio River Basin and elevated Hg levels were detected in the Tennessee River, the former may affect the mainstem Mississippi River, whereas the latter probably do not. Sediment‐associated concentrations of Ag, Cu, Pb, Zn, Cd, Cr, Co, Ba, Mo, Sb, Hg, and Fe are markedly elevated in the upper Columbia Basin, and appear to be detectable (Zn, Cd) as far downstream as the middle of the basin. These elevated concentrations seem to result from mining and/or mining‐related activities. Consistently detectable concentrations of dissolved Se were found only in the Colorado River Basin.

Calculated average annual suspended sediment fluxes at the mouths of the Mississippi and Rio Grande Basins were below, whereas those for the Columbia and Colorado Basins were above previously published annual values. Downstream suspended sediment‐associated and total trace element fluxes increase in the Mississippi and Columbia Basins, whereas fluxes markedly decrease in the Colorado Basin. No consistent pattern in trace element fluxes was detected in the Rio Grande Basin. Published in 2001 by John Wiley & Sons, Ltd.
Carbon and nitrogen isotopic compositions of particulate organic matter in four large river systems across the United States
Authors: Kendall Carol , Silva Steven R. , Kelly Valerie J.
Published: September 2002

Riverine particulate organic matter (POM) samples were collected bi‐weekly to monthly from 40 sites in the Mississippi, Colorado, Rio Grande, and Columbia River Basins (USA) in 1996–97 and analysed for carbon and nitrogen stable isotopic compositions. These isotopic compositions and C : N ratios were used to identify four endmember sources of POM: plankton, fresh terrestrial plant material, aquatic plants, and soil organic material. This large‐scale study also incorporated ancillary chemical and hydrologic data to refine and extend the interpretations of POM sources beyond the source characterizations that could be done solely with isotopic and elemental ratios. The ancillary data were especially useful for differentiating between seasonal changes in POM source materials and the effects of local nutrient sources and in‐stream biogeochemical processes.

Average values of δ13C and C : N for all four river systems suggested that plankton is the dominant source of POM in these rivers, with higher percentages of plankton downstream of reservoirs. Although the temporal patterns in some rivers are complex, the low δ13C and C : N values in spring and summer probably indicate plankton blooms, whereas relatively elevated values in fall and winter are consistent with greater proportions of decaying aquatic vegetation and/or terrestrial material. Seasonal shifts in the δ13C of POM when the C : N remains relatively constant probably indicate changes in the relative rates of photosynthesis and respiration. Periodic inputs of plant detritus are suggested by C : N ratios >15, principally on the Columbia and Ohio Rivers. The δ15N and δ13C also reflect the importance of internal and external sources of dissolved carbon and nitrogen, and the degree of in‐stream processing. Elevated δ15N values at some sites probably reflect inputs from sewage and/or animal waste. This information on the spatial and temporal variation in sources of POM in four major river systems should prove useful in future food web and nutrient transport studies. Published in 2001 by John Wiley & Sons, Ltd.
Hillslope and wetland hydrodynamics in a tussock grassland, South Island, New Zealand
Authors: Bowden William B. , Fahey Barry D. , Ekanayake Jagath , Murray Dave L.
Published: September 2002

Previous research on two experimental catchments at the Glendhu Forest (Otago) showed that runoff dynamics from this landscape differ substantially from other areas in New Zealand. In particular, the recession curves from these catchments have two distinct phases: a rapid decline for a period of several hours, followed by a slow decline that may last many days to weeks. In the current study, soil water matric potential measurements indicated that perched saturated zones develop very rapidly in the surface (0–30 cm) soil horizons. Deep (50–250 cm) loess horizons remain moist throughout the year and may be near or at saturation at the bedrock contact, and respond only slowly to rain events. Soils in the middle horizons are often drier than the surface soil above or the deep soils below. Throughflow measurements showed that storm runoff occurs primarily as interflow through a retentive but pervious mat of mosses, litter, and roots at the soil surface. Despite the presence of abundant earthworm burrows, less water is transmitted through the soil horizon just below this surface mat. Only a small fraction of stormflow was transmitted through the deep, mineral horizons. However, baseflow could be sustained for long periods (up to 4 weeks) from unsaturated flow of soil moisture stored in the deep loess horizons. Water storage in bog peats and associated riparian soils (which are numerous in this area) is insufficient to sustain baseflow for more than a few days. The results from this study are consistent with previous hydrometric, soils, and isotopic observations and suggest that any land‐use practices that disrupt the surface soil horizons are likely to change the runoff characteristics of this area. Copyright © 2001 John Wiley & Sons, Ltd.
Quantifying contributions to storm runoff through end‐member mixing analysis and hydrologic measurements at the Panola Mountain Research Watershed (Georgia, USA)
Authors: Burns Douglas A. , McDonnell Jeffrey J. , Hooper Richard P. , Peters Norman E. , Freer James E. , Kendall Carol , Beven Keith
Published: September 2002

The geographic sources and hydrologic flow paths of stormflow in small catchments are not well understood because of limitations in sampling methods and insufficient resolution of potential end members. To address these limitations, an extensive hydrologic dataset was collected at a 10 ha catchment at Panola Mountain Research Watershed near Atlanta, GA, to quantify the contribution of three geographic sources of stormflow. Samples of stream water, runoff from an outcrop, and hillslope subsurface stormflow were collected during two rainstorms in the winter of 1996, and an end‐member mixing analysis model that included five solutes was developed. Runoff from the outcrop, which occupies about one‐third of the catchment area, contributed 50–55% of the peak streamflow during the 2 February rainstorm, and 80–85% of the peak streamflow during the 6–7 March rainstorm; it also contributed about 50% to total streamflow during the dry winter conditions that preceded the 6–7 March storm. Riparian groundwater runoff was the largest component of stream runoff (80–100%) early during rising streamflow and throughout stream recession, and contributed about 50% to total stream runoff during the 2 February storm, which was preceded by wet winter conditions. Hillslope runoff contributed 25–30% to peak stream runoff and 15–18% to total stream runoff during both storms. The temporal response of the three runoff components showed general agreement with hydrologic measurements from the catchment during each storm. Estimates of recharge from the outcrop to the riparian aquifer that were independent of model calculations indicated that storage in the riparian aquifer could account for the volume of rain that fell on the outcrop but did not contribute to stream runoff. The results of this study generally indicate that improvements in the ability of mixing models to describe the hydrologic response accurately in forested catchments may depend on better identification, and detailed spatial and temporal characterization of the mobile waters from the principal hydrologic source areas that contribute to stream runoff. Copyright © 2001 John Wiley & Sons, Ltd.
Topographic controls on the chemistry of subsurface stormflow
Authors: Welsch Daniel L. , Kroll Charles N. , McDonnell Jeffrey J. , Burns Douglas A.
Published: September 2002

Models are needed that describe how topography and other watershed characteristics affect the chemical composition of runoff waters, yet little spatially distributed data exist to develop such models. A topographically driven flushing mechanism for nitrate (NO3−) and dissolved organic carbon has been described in recent literature; however, this mechanism has not yet been thoroughly tested. A 24 ha catchment in the Catskill Mountains of New York was clearcut in the winter of 1996–97, resulting in elevated NO3− concentrations in soil water, groundwater and streamflow. We sampled shallow subsurface stormflow (SSSF) and streamflow six times during the spring and summer of 1998, 1 year after the harvest. We used a spatially distributed network of piezometers to investigate the relationship between topography and SSSF chemistry. Several indices of topography were computed, including the commonly employed topographic index of Beven and Kirkby (1979; Hydrological Sciences Bulletin 24: 43–69). Topographic index was positively correlated with NO3− concentrations in SSSF. The strength of the NO3−–topography relationship was best explained by antecedent soil temperature and antecedent precipitation conditions. Results suggest a topographically driven flushing of high NO3− shallow soil at the site during storm events. Copyright © 2001 John Wiley & Sons, Ltd.
Banking reform in India and China
Authors: Sáez Lawrence
Published: September 2002

This paper analyzes the important process about financial reform in the area of bank illiquidity in low‐income emerging markets. This process is taking place within the context of a debate as to whether or not governments should try to rehabilitate existing state‐owned banks or allow a new or parallel banking system to emerge in order to reduce non‐performing assets from state‐owned commercial banks. A comparison of institutional development in China and India suggests that new entry rather than the rehabilitation approach may work more favorably to reduce non‐performing assets. The paper offers an explanation as to why governments choose rehabilitation over new entry. Copyright © 2001 John Wiley & Sons, Ltd.
Real exchange rate effects on the balance of trade: cointegration and the Marshall–Lerner condition
Authors: Boyd Derick , Caporale Gugielmo Maria , Smith Ron
Published: September 2002

A typical finding in the empirical literature is that import and export demand elasticities are rather low, and that the Marshall–Lerner (ML) condition does not hold. However, despite the evidence against the ML condition, the consensus is that real devaluations do improve the balance of trade, though after a lag because of J‐curve effects. The aim of this paper is to try and measure the effects of the real exchange rate on the balance of payments using structural cointegrating vector autoregressive distributed lag (VARDL) models for domestic and foreign output, the balance of trade and the real exchange rate. Small systems are estimated for eight OECD countries to investigate long‐run cointegration. Generalized impulse response functions are calculated to investigate the response to shocks. These show evidence of J‐effects. The VARDL estimates suggest a single cointegrating vector and that output and the real exchange rate can be treated as weakly exogenous for the parameters of the balance of payment equation. This allows estimation using a single‐equation ARDL. Although there is considerable heterogeneity, overall the results suggest that the ML condition is satisfied in the long run. Copyright © 2001 John Wiley & Sons, Ltd.
Special report: NIST workshop on reference data for the properties of biomaterials
Authors: Tesk John A.
Published: September 2002

A workshop on Reference Data for Biomaterials was held at the National Institute of Standards and Technology (NIST) on July 27, 2000. The primary purpose of the workshop was to determine whether needs existed for the establishment of reference data (RD) databases on the properties of biomaterials. Special attention was given to critiqued RD such as those traditionally found in databases that are established within the NIST Standard Reference Data Program. Critiqued data are data that have been critically evaluated for issues dealing with components of uncertainty, experimental design (details, descriptions, and appropriateness), measurement methods (appropriateness), conclusions drawn from the data, and so forth. Among the workshop's 65 registrants were representatives from industry, the National Institutes of Health (NIH), the Food and Drug Administration (FDA), and academia. These joined with NIST staff to address reference biomaterial property database needs within five categories: orthopedic, cardiovascular, ophthalmologic, tissue‐engineered, and dental biomaterials. A general session on other issues focused specifically on database accesses (portals), contents, and maintenance. While the workshop's intended focus was on critiqued RD, it was suggested that closely related issues be considered as well. In this way, a more comprehensive assessment of opportunities for the cooperation of NIST with the biomaterials community might be developed. As a result, the needs for noncritiqued data and for reference materials (RMs), useful for developing data, also became a part of the focus of the workshop. Hence, this article presents the results from the breakout sessions of the workshop according to two categories: reference data and databases, and reference materials. In the following summary, the workshop is presented in the following order: An introduction to databases, resource presentations, action items identified in breakout sessions, assessment of resources (personnel and monetary) needed to work on action items, and portals for databases. Except for the individual concurrent breakout sessions themselves, all other sessions of the workshop were participated in fully by those in attendance. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 463–466, 2001
Calcium‐phosphate surface coating by casting to improve bioactivity of titanium
Authors: Sohmura Taiji , Tamasaki Hideki , Ohara Toru , Takahashi Junzo
Published: September 2002

In order to improve the bioactivity of titanium, an original surface treatment was attempted with the use of a casting technique was attempted. Pure titanium was cast into a special graphite mold in which the cavity wall was coated with hydroxyapatite (HA) powder. According to analyses of X‐ray diffraction and EDX, the existence of HA and CaO and uptake of Ca and P on the surface of the titanium castings were identified. By immersing the specimen in Hank's solution, the concentrations of Ca and P on the surface increased with immersion time, and the formation of a thin layer with characteristics of spherical HA precipitates was observed after 1 week. The concentrations of Ca and P elements and the Ca/P ratio on the HA layer increased with immersion time. The formation of the HA layer on the titanium cast by this treatment was significantly accelerated compared with pure titanium. The present surface treatment of Ti is expected to improve early bone fixation of Ti implants. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 478–485, 2001
Response of alkalinization or acidification by phytohemagglutinin is dependent on the activity of protein kinase C in human peripheral T Cells
Authors: Chien Eileen Jea , Hsieh Dennis J‐Y , E‐C Wang John
Published: September 2002

The increase of intracellular free calcium concentration ([Ca2+]i) and protein kinase C (PKC) activity are two major early mitogenic signals to initiate proliferation of human T cells. However, a rapid change in intracellular pH (pHi), acidification or alkalinization during the activation, is also associated after these two signals. The aim of this study was to define whether the change in pHi is affected by calcium and protein kinase C (PKC), in phytohemagglutinin (PHA)‐stimulated T cells. T cells were isolated from human peripheral blood. The [Ca2+]i and the pHi were measured using, respectively, the fluorescent dyes, Fura‐2, and BCECF. In addition, down‐regulation of PKC activity by PMA (1 μM, 18 h) was confirmed in these cells using a protein kinase assay. The results indicated that, (1) alkalinization was induced by PHA or PMA in T cells; the results of alkalinization was PKC‐dependent and Ca2+‐independent, (2) in PKC down‐regulated T cells, PHA induced acidification; this effect was enhanced by pre‐treating the cells with the Na+/H+ exchange inhibitor, 5‐(N,N‐dimethyl)‐amiloride, (DMA, 10 μM, 20 min), (3) the acidification was dependent on the Ca2+ influx and blocked by removal of extracellular calcium or the addition of the inorganic channel blocker, Ni2+, and (4) Thapsigargin (TG), a Ca2+‐ATPase inhibitor, confirmed that acidification by the Ca2+ influx occurred in T cells in which PKC was not down‐regulated. These findings indicate two mechanisms, alkalinization by PKC and acidification by Ca2+ influx, exist in regulating pHi in T cells. This is the first report that PHA stimulates the acidification by Ca2+ influx but not alkalinization in T cells after down‐regulation of PKC. In conclusion, the activity of PKC in T cells determines the response in alkalinization or acidification by PHA. J. Cell. Biochem. 81: 604–612, 2001. © 2001 Wiley‐Liss, Inc.
Effects of cannabinoids on LPS‐stimulated inflammatory mediator release from macrophages: Involvement of eicosanoids
Authors: Chang Ying‐Hsin , Lee Sho Tone , Lin Wan‐Wan
Published: September 2002

Δ9‐Tetrahydrocannabinol (Δ9‐THC) is the major psychoactive component of marijuana and elicits pharmacological actions via cannabinoid receptors. Anandamide (AEA) and 2‐arachidonoyl‐glycerol (2‐AG) are endogenous ligands for cannabinoid receptors, which because of their structural similarities to arachidonic acid (AA), AEA, and 2‐AG could serve as substrates for lipoxygenases and cyclooxygenases (COXs) that metabolize polyunsaturated fatty acids to potent bioactive molecules. In this study, we have compared the effects of Δ9‐THC, AEA, 2‐AG, and another cannabinoid agonist, indomethacin morpholinylamide (IMMA), on lipopolysaccharide (LPS)‐induced NO, IL‐6, and PGE2 release from J774 macrophages. Δ9‐THC, IMMA, and AEA diminish LPS‐induced NO and IL‐6 production in a concentration‐dependent manner. 2‐AG inhibits the production of IL‐6 but slightly increases iNOS‐dependent NO production. Δ9‐THC and IMMA also inhibit LPS‐induced PGE2 production and COX‐2 induction, while AEA and 2‐AG have no effects. These discrepant results of 2‐AG on iNOS and COX‐2 induction might be due to its bioactive metabolites, AA and PGE2, whose incubation cause the potentiation of both iNOS and COX‐2 induction. On the contrary, the AEA metabolite, PGE2‐ethanolamide, influences neither the LPS‐induced NO nor IL‐6 production. Taken together, direct cannabinoid receptor activation leads to anti‐inflammatory action via inhibition of macrophage function. The endogenous cannabinoid, 2‐AG, also serves as a substrate for COX‐catalyzing PGE2 production, which in turn modulates the action of CB2. J. Cell. Biochem. 81: 715–723, 2001. © 2001 Wiley‐Liss, Inc.
Removal of lignin in a liquid system by an isolated fungus
Authors: Sakurai Akihiko , Yamamoto Tatsuhiko , Makabe Akemi , Kinoshita Shinichi , Sakakibara Mikio
Published: September 2002

The screening of a strain which could perform lignin removal was carried out. Based on taxonomic study the isolated strain (LM‐2) was identified as Penicillium sp. LM‐2 could decolorize 0.6 g dm−3 lignin within 4 days in a shaking culture at 25 °C. The efficiency of decolorization of the lignin was over 80% in the pH range of 4.0–6.0, but was low above pH 6.2. The rise of temperature had a slight adverse effect on the lignin decolorization in the range of 25–35 °C. Lignolytic enzymes such as lignin peroxidase, manganese peroxidase and laccase were not detected in the culture broth or within the fungal cells. The lignin was removed from the high molecular weight fraction mainly by adsorption and accumulation inside the cells.

© 2001 Society of Chemical Industry
Removal of phosphates from aqueous solutions by using bauxite. I: Effect of pH on the adsorption of various phosphates
Authors: Altundoğan H Soner , Tümen Fikret
Published: September 2002

In this study, the effect of pH on adsorption of various forms of phosphate onto bauxite was investigated. For this purpose, the adsorption and desorption of inorganic (ortho and condensed) and organic phosphate species were studied. It was observed that the adsorption tendency of the various phosphate forms was different and depended on pH. Maximum adsorption efficiencies for all phosphate forms were achieved in slightly acidic conditions (pH 3.2–5.5). The results of adsorption and desorption studies showed that the adsorption of phosphates onto bauxite is based on a ligand exchange mechanism. The adsorption mechanism of inorganic condensed phosphates and organic phosphates is thought to be more complex than that of orthophosphate. It can be stated that the adsorption of organic phosphates is dependent on the functionality, number, and variety of organic groups. The results of experiments carried out with mixed phosphate solutions showed that the adsorption yields of various phosphate forms are dependent on the composition of the solution. The relative adsorptivity of various phosphates was found to be in the general order of hexametaphosphate > pyrophosphate > orthophosphate > tripolyphosphate > adenosine triphosphate > glycerophosphate > glucose‐1‐phosphate.

© 2001 Society of Chemical Industry
Sorption of tannic acid on zirconium pillared clay
Authors: Vinod V P , Anirudhan T S
Published: September 2002

Zirconium pillared clay (PILC) was prepared using montmorillonite as the base clay. Adsorption of tannic acid (tannin) was studied by a batch equilibrium technique, as a function of adsorbate concentration, temperature, pH, agitation speed, particle size of the adsorbent and ionic strength. The process of uptake is governed by diffusion controlled first‐order reversible rate kinetics. The higher uptake for the pH range 4.0–6.0 was attributed to external hydrogen bonding between phenolic‐OH groups of tannin molecules and the hydrogen bonding sites on the clay. The removal of tannin by adsorption was found to be >99.0% depending on the initial concentration in the pH range of 4.0–6.0. The process involves both film and pore diffusion to different extents. The effects of solute concentration, temperature, agitation speed and particle size on the diffusion rate were investigated. Tannin uptake was found to increase with ionic strength due to the compression of diffuse double layers. The applicability of Langmuir and Freundlich isotherm models has been tested. The maximum adsorption capacity of PILC was found to be 45.8 µmol g−1 of clay and the affinity constant is 2.9 × 10−2 dm3 µmol−1 at 30 °C. Thermodynamic parameters such as ΔG °,ΔH ° and ΔS ° were calculated to predict the nature of adsorption. The isosteric enthalpies of adsorption were also determined and found to decrease with increasing surface coverage. Regeneration with hot water (60 °C) has been investigated for several cycles with a view to recovering the adsorbed tannin and also restoring the sorbent to its original state.

Copyright © 2001 Society of Chemical Industry
Sonography of the normal scapholunate ligament and scapholunate joint space
Authors: Griffith James Francis , Nin Chan David Po , Ho Pak Cheong , Zhao Li , Hung Leung Kim , Metreweli Constantine
Published: September 2002

Purpose

The aims of this study were to assess the visibility of the normal scapholunate ligament on sonography and to establish the normal scapholunate joint space width in the neutral position and radial and ulnar deviation.

Methods

Two hundred normal wrists in 100 subjects (55 men and 45 women; mean age, 40 years; range, 19–83 years) were examined with high‐resolution sonography (5–12‐MHz linear‐array transducer). The visibility and thickness of the scapholunate ligament were recorded. The width of the scapholunate joint space, or interval, was measured in the neutral position and radial and ulnar deviation. The width of the distal radius was recorded as a comparative standard for the patients' body habitus.

Results

The dorsal scapholunate ligament was completely (100%) visible in 95 wrists (48%), partially (≥ 50%) visible in 60 (30%), barely (< 50%) visible in 15 (8%), and not visible in 30 (15%). The volar scapholunate ligament was completely visible in 13 wrists (7%), partially visible in 17 (9%), barely visible in 15 (8%), and not visible in 151 (76%). The proximal component of the ligament was not visible in any subject. Measurement of the scapholunate interval was limited by the lack of identifiable anatomic marks for reference. The mean width of the dorsal scapholunate interval was 4.2 mm (range, 2.3–6.3 mm) in the neutral position. The interval did not differ more than 2.5 mm between the left and right wrists. No predictable change in width on ulnar or radial deviation was evident. The mean scapholunate intervals and mean distal radial width were significantly wider in men than in women and on the right side than on the left side.

Conclusions

The dorsal scapholunate ligament is completely or partially visible in 78% of normal wrists. Its detection following injury may help to exclude the possibility of scapholunate dissociation. There is a quite wide variation in scapholunate interval widths on sonography and an unpredictable response with stress testing. The absence of a visible scapholunate ligament on sonography does not indicate injury. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:223–229, 2001.
Real‐time sonography to estimate muscle thickness: Comparison with MRI and CT
Authors: Dupont Anne‐Caroline , Sauerbrei Eric E. , Fenton Paul V. , Shragge Peter C. , Loeb Gerald E. , Richmond Frances J. R.
Published: September 2002

Purpose

We investigated the feasibility of using real‐time sonography to measure muscle thickness. Clinically, this technique would be used to measure the thickness of human muscles in which intramuscular microstimulators have been implanted to treat or prevent disuse atrophy.

Methods

Porcine muscles were implanted with microstimulators and imaged with sonography, MRI, and CT to assess image artifacts created by the microstimulators and to design protocols for image alignment between methods. Sonography and MRI were then used to image the deltoid and supraspinatus muscles of 6 healthy human subjects.

Results

Microstimulators could be imaged with all 3 methods, producing only small imaging artifacts. Muscle‐thickness measurements agreed well between methods, particularly when external markers were used to precisely align the imaging planes. The correlation coefficients for sonographic and MRI measurements were 0.96 for the supraspinatus and 0.97 for the deltoid muscle. Repeated sonographic measurements had a low coefficient of variation: 2.3% for the supraspinatus and 3.1% for the deltoid muscle.

Conclusions

Real‐time sonography is a relatively simple and inexpensive method of accurately measuring muscle thickness as long as the operator adheres to a strict imaging protocol and avoids excessive pressure with the transducer. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:230–236, 2001.
Role of nitric oxide in the pathogenesis of muscular dystrophies: A “two hit” hypothesis of the cause of muscle necrosis
Authors: Rando Thomas A.
Published: September 2002

Although the genetic and biochemical bases of many of the muscular dystrophies have been elucidated, the pathophysiological mechanisms leading to muscle cell death and degeneration remain elusive. Among the most well studied of the dystrophies are those due to defects in proteins that make up the dystrophin‐glycoprotein complex (DGC). There has been much interest in the role of nitric oxide (NO•) in the pathogenesis of these diseases because the enzyme that synthesizes NO•, nitric oxide synthase (NOS), is associated with the DGC. Recent studies of dystrophies related to DGC defects suggest that one mechanism of cellular injury is functional ischemia related to alterations in cellular NOS and disruption of a normal protective action of NO•. This protective action is the prevention of local ischemia during contraction‐induced increases in sympathetic vasoconstriction. However, the loss of this protection, alone, does not explain the subsequent muscle cell death and degeneration since mice lacking neuronal NOS (the predominant isoform expressed in muscle) do not develop a muscular dystrophy. Thus, there must be additional biochemical changes conferred upon the cells by these DGC defects, and these changes are discussed in terms of a proposed “two hit” hypothesis of the pathogenetic mechanisms that underlie the muscular dystrophies. According to this hypothesis, pathogenic defects in the DGC have at least two biochemical consequences: a reduction in NO•‐mediated protection against ischemia, and an increase in cellular susceptibility to metabolic stress. Either one alone may be insufficient to lead to muscle cell death. However, in combination, the biochemical consequences are sufficient to cause muscle degeneration. The role of oxidative stress as a final common pathophysiologic pathway is discussed in terms of data showing that oxidative injury precedes pathologic changes and that muscle cells with defects in the DGC have an increased susceptibility to oxidant challenges. Accordingly, this “two hit” hypothesis may explain many of the complex spatial and temporal variations in disease expression that characterize the muscular dystrophies, such as grouped necrosis, a pre‐necrotic phase of the disease, and selective muscle involvement. Microsc. Res. Tech. 55:223–235, 2001. © 2001 Wiley‐Liss, Inc.
Detection of reactive oxygen and reactive nitrogen species in skeletal muscle
Authors: Murrant Coral L. , Reid Michael B.
Published: September 2002

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are usually identified with pathological states and mediators of cellular injury. However, over the last decade ROS and RNS have been identified in skeletal muscle under physiological conditions. Detection of ROS and RNS production by skeletal muscle cells is fundamental to the problem of differentiating between physiological and pathological levels. The goal of this paper is to review the techniques that have been used to detect ROS and RNS in skeletal muscle. Electron spin resonance, fluorescent assays, cyotchrome c reduction, chemiluminescence, hydroxylation of salicylate, and nitration of phenylalanine are some of the assay systems that have been used thus far. A large body of evidence now indicates that ROS and RNS are continually produced by many different skeletal muscle types studied in vivo, in situ, and in vitro. Under resting conditions, ROS and RNS are detectable in both intracellular and extracellular compartments. Production increases during both non‐fatiguing and fatiguing muscle contractions. In the absence of disease, the individual molecular species detected in skeletal muscle include parent radicals for the ROS and RNS cascades: superoxide anions and nitric oxide. Both are generated at rates estimated to range from pmol‐to‐nmol/mg muscle/minute. Evidence indicates that hydrogen peroxide, hydroxyl radicals, and peroxynitrite are also present under physiological conditions. However, the molecular species that mediate specific biological effects remains largely undetermined, as do the sources of ROS and RNS within muscle fibers. Eventual delineation of the mechanisms whereby ROS and RNS regulate cellular function will hinge on our understanding of the production and distribution of ROS and RNS within skeletal muscle. Microsc. Res. Tech. 55:236–248, 2001. © 2001 Wiley‐Liss, Inc.
Endogenous innovation growth theory and regional income convergence in China
Authors: Wei Yingqi , Liu Xiaming , Song Haiyan , Romilly Peter
Published: September 2002

Endogenous innovation growth theory is tested by using panel data for 27 provinces across China. R&D expenditure and openness are added to the standard convergence regressions to control for different structural characteristics in each province. A standardized ‘t‐bar’ test for unit roots is applied to examine the properties of the data and identify a long‐run relationship among the variables. By allowing for differences in the aggregate production function across regions, we find evidence of convergence. The empirical results support the endogenous innovation growth model in which regional per capita income can converge given technological diffusion, transfer and imitation. Copyright © 2001 John Wiley & Sons, Ltd.