bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of reactive oxygen species in the regulation of tubular function
Authors: Garvin J. L. , Ortiz P. A. 
Published: November 2003

AbstractThe phrase reactive oxygen species covers a number of molecules and atoms, including the quintessential member of the group, O2−; singlet oxygen; H2O2; organic peroxides; and OONO−. While nitric oxide (NO) is also technically a member of the reactive oxygen species family, it is generally considered with a different class of compounds and will not be considered here. To our knowledge, there are currently no published data reporting the effects of reactive oxygen species on net transepithelial flux in the proximal nephron. However, there is evidence that OONO− regulates Na+/K+ adenosine triphosphatase (ATPase) activity as well as paracellular permeability. While it is easy to speculate that such an effect on the pump would decrease net transepithelial solute and water reabsorption, one cannot do so without knowing how other transporters are affected. O2− stimulates NaCl absorption by the thick ascending limb by activating protein kinase C and blunting the effects of NO. The effects of O2− on thick ascending limb NaCl absorption may be important for the initiation of salt‐sensitive hypertension. To our knowledge, there are no published data concerning the role of reactive oxygen species in the regulation of solute absorption in either the distal convoluted tubule or the collecting duct. However, OONO− inhibits basolateral K+ channels in the cortical collecting duct, although the net effect of such inhibition is unknown.Conclusion:  While the regulation of tubular transport by reactive oxygen species is important to overall salt and water balance, we know very little about where and how these regulators act along the nephron.
Renal and vascular oxidative stress and salt‐sensitivity of arterial pressure
Authors: Manning R. D. , Meng S. , Tian N. 
Published: November 2003

AbstractOxidative stress occurs in a tissue or in the whole body when the total oxidant production exceeds the antioxidant capacity. Recent studies in human essential hypertension indicate that free radical production is increased and antioxidant levels are decreased, and more than one‐half of these hypertensives have a salt‐sensitive type of hypertension with progressive renal damage. Increased oxidative stress may also play a critical role in animal models of salt‐sensitive hypertension. The stroke‐prone spontaneously hypertensive rats (SHRSP) exhibits salt‐sensitivity, vascular release of superoxide is increased, and total plasma antioxidant capacity is decreased. The superoxide release in the SHRSP rats inactivates nitric oxide, and superoxide dismutase (SOD) administration returns the bioactive nitric oxide levels to normal. The deoxycorticosterone acetate (DOCA)‐salt hypertensive rat is salt‐sensitive, aortic superoxide production is increased, and renal inflammation is significant. Treatment of the DOCA‐salt rats with apocynin, an NADPH oxidase inhibitor, decreased aortic superoxide production and decreased arterial pressure. The Dahl salt‐sensitive (S) rat has increased mesenteric microvascular and renal superoxide production and increased plasma levels of H2O2. The renal protein expression of SOD is decreased in the kidney of Dahl S rats, and long‐term administration of Tempol, a superoxide mimetic, significantly decreased arterial pressure and renal damage. In conclusion, both human hypertension and experimental models of salt‐sensitive hypertension have increased superoxide release, decreased antioxidant capacity and elevated renal damage.
E‐exchange and the Boundary between Households and Organizations
Authors: Lindbeck Assar , Wikström Solveig 
Published: November 2003

SummaryThe new information and communication technology, ICT, induces households to take over tasks from firms and government agencies, using tools and systems provided by these very same organizations. The result is often joint production activities. We argue that the importance of ICT for the exchange process between households and organizations is underestimated by only considering the consequences for the last stage of the process, i.e., the final purchase of goods and services. Our analysis of household behavior utilizes a modified version of Gary Becker’s model of the household as a combined producer‐consumer.
The Future of the Defence Firm
Authors: Hartley Keith , Sandler Todd 
Published: November 2003

SummaryThis paper focuses on the future of the defence firm. It forecasts that the defence firm of 2050 will be radically different, reflecting a combination of technology, economic and political factors. To provide insights into the future, the paper starts by outlining recent changes in the size, structure and organization of defence firms and industries. It concludes by suggesting that the defence firm has a future and that it will focus on systems integration with new and different forms of industrial organization and will include new entrants.
A Divided Europe? Regional Convergence and Neighbourhood Spillover Effects
Authors: Carrington Anca 
Published: November 2003

SummaryWhile the stylised fact that, around the world, areas of rapid growth are geographically distinct from those with a poor growth performance, is easily accepted, little effort has been made in the empirical literature to incorporate location into the analysis of regional convergence in terms of economic growth. This paper provides a quantitative evaluation of the role of location in regional convergence, using the argument that growth in each region depends not only on its own characteristics but also on those of the regions that form the neighbourhood to which it belongs. Applying spatial econometrics it is found that, during the 1990s, opposing forces were exerting their influence across the EU: while regions did converge at a rate close to the 2 percent mark, neighbourhoods of regions diverged at an almost equal rate, leaving a net effect of convergence considerably smaller than the one previously reported in the literature.
Patients' perceptions of nursing care in the hospital setting
Authors: Schmidt Lee A. 
Published: November 2003

Background.  Patient satisfaction and patient satisfaction with nursing care data are routinely collected as an indicator of the quality of services delivered. Despite the widespread collection and reporting of these data, the theoretical basis of patient satisfaction and patient satisfaction with nursing care remains unclear. Without a clear theoretical base, interpretation of patient satisfaction findings is hampered and the entire line of patient satisfaction research is of questionable validity. It has been suggested that, to understand patient satisfaction, patient perceptions of their care must first be understood.Aim.  The aim of this study was to discover patients’ perceptions of the nursing care they receive in the hospital setting.Method.  Grounded theory method was used in this study of eight medical–surgical patients recently discharged from an academic medical centre in the south‐eastern United States of America (USA). Participants were interviewed and the verbatim transcripts analysed using the constant comparative method.Findings.  Four categories of patient perceptions of their nursing care emerged from the data. ‘Seeing the individual patient’ captures the unique nature of the nursing care experience for each patient. ‘Explaining’ represents the informal explanations given by nursing staff as they provide care. ‘Responding’ refers to both the character and timeliness of nursing staff's responses to patient requests or symptoms. ‘Watching over’ represents the surveillance activities of nursing staff.Conclusions.  The categories identified in this study may be used in efforts to further develop a formal theory of patient satisfaction with nursing care. These categories should also be tested with patients possessing a wider range of characteristics, to assess the transferability of the findings.
How the health visitor can help when problems between parents add to postnatal stress
Authors: Simons John , Reynolds Jenny , Mannion Joe , Morison Linda 
Published: November 2003

Background.  Caring for a baby can provoke or intensify discord between parents, with adverse effects on their own well‐being and their parenting.Aim.  The aim of this study was to appraise evidence obtained from 450 mothers on the quality of the parents’ relationship during the postnatal period and the value of support provided by health visitors in cases of discord.Design.  The health visitors were based at nine clinics in an outer London borough, and had been trained on a four‐day course (the Brief Encounters course) to screen mothers for relationship problems at the 6–8‐week check and to offer support (supportive listening, practical advice, referral) if problems were revealed. Data on relationship quality were obtained by a self‐report screening scale completed at the 6–8‐week check and again at the 12‐week visit for immunizations, when the scale was included in a self‐report questionnaire on help received from the health visitor. Intervention records kept by the health visitor showed what form any support had taken. Some 6 weeks later, 25 of the 82 mothers offered support, and their health visitors, were interviewed about their experience of the intervention.Results.  One in five mothers were identified as having a relationship problem at the 6–8‐week check. Most were offered support. One in five of the 351 mothers who completed a questionnaire at the 12‐week visit reported receiving support in improving their relationship. The follow‐up interviews showed that most mothers valued this support. Responses to a questionnaire completed by health visitors showed that most were enthusiastic about its benefits.Conclusions.  A four‐day training course for health visitors enabled them to screen for relationship problems during the postnatal period and to provide support when required in a way that was valued by mothers. Most health visitors were enthusiastic about the value of the intervention in improving their contribution to family welfare.
Translating clinical tools in nursing practice
Authors: Dunckley Maria , Hughes Rhidian , Addington‐Hall Julia M. , Higginson Irene J. 
Published: November 2003

Background.  The widespread use of clinical tools in nursing practice reflects their usefulness in guiding patient care, evaluating treatment effectiveness and conducting audit. Cultural awareness and the provision of culturally competent care is a high priority for nurses in the United Kingdom (UK), given patterns of increasing ethnic diversity. However, meeting the individual needs of patients can be difficult when language barriers hinder communication. One way to address these difficulties is to translate existing clinical tools.Aim.  The aim of this paper is to appraise the potential for, and limitations of, translating clinical tools for use in nursing practice.Discussion.  Drawing on a range of studies from the disciplines of health and social science, this review describes and discusses some key considerations relevant to translating clinical tools in nursing. These considerations include the need to ensure cultural equivalence, lack of familiarity with clinical tool formats in some cultures and its impact on responses, and low literacy levels in some populations.Conclusion.  Clinical tools provide benefits in identifying patients’ problems, guiding patient care, and evaluating treatments and interventions. Translating these tools can help to bridge the language gap that hinders good communication between nurses and patients. Translated clinical tools can be of acceptable cultural equivalence and validity if high quality translation methodologies are employed, together with an awareness of culturally relevant issues when interpreting the information gained from the tools.
Effect of interleukin‐15 on anti‐CD3/anti‐CD28 induced apoptosis of umbilical cord blood CD4+ T cells
Authors: Lin Syh‐Jae , Yu Jung‐Chuan , Cheng Po‐Jen , Hsiao Shiu‐Shan , Kuo Ming‐Ling 
Published: November 2003

Abstract: Objectives: Interleukin‐15 (IL‐15) has potential therapeutic advantage for patients receiving umbilical cord blood (CB) transplantation. The present study aims to examine the ability of IL‐15 to modulate the survival, maturation, and function of anti‐CD3/anti‐CD28 stimulated CB CD4+ T cells, in comparison with responses from adult peripheral blood (APB) CD4+ T cells.Methods: Enriched CB and APB CD4+ T cells were stimulated with anti‐CD3 and anti‐CD28 (anti‐CD3/anti‐CD28) in the presence or absence of IL‐15 (10 ng/mL) for 5 d. The percentages of apoptotic cells were assessed by propidium iodide/annexin‐V flow cytometric staining. T‐cell activation was analyzed with the expression of surface markers (CD45RO/CD69/CD25). Interferon‐γ (IFN‐γ) and tumor necrosis factor‐α (TNF‐α) production in culture supernatant was determined by enzyme‐linked immunosorbent assay.Results: CB CD4+ T cells had a higher survival and lower apoptotic response following anti‐CD3/anti‐CD28 stimulation, compared with APB CD4+ T cells. IL‐15 enhanced apoptosis and promoted CD45RO conversion of anti‐CD3/anti‐CD28 activated CB CD4+ T cells, an effect not observed with APB CD4+ T cells. Although activated CB CD4+ T cells expressed comparable level of CD69/CD25 expression to adults, IFN‐γ production of activated CB CD4+ T cells was markedly deficient compared with that of corresponding APB CD4+ T cells. Exogenous IL‐15 further enhanced the production of IFN‐γ, but not TNF‐α, of activated CB CD4+ T cells.Conclusions: IL‐15 preferentially resulted in an activation‐enhancing effect on CB CD4+ T cells, accompanied by increased apoptosis. Our finding may have therapeutic implications while designing IL‐15 immunotherapy for patients receiving CB transplant.
Flavones inhibit proliferation and increase mediator content in human leukemic mast cells (HMC‐1)
Authors: Alexandrakis Michael , Letourneau Richard , Kempuraj Durajisamy , Grzybowska Kristiana Kandere , Huang Man , Christodoulou Spyridon , Boucher William , Seretakis Dimitris , Theoharides Theoharis C. 
Published: November 2003

Abstract: Objective: Mast cells are involved in allergic and inflammatory reactions. These cells are also increased in the bone marrow, skin, and other organs in systemic mastocytosis. Flavonoids are naturally occurring molecules with antioxidant, cytoprotective, and anti‐inflammatory activities. Some flavonoids, like quercetin, inhibit the growth of certain malignant cells in culture. Quercetin also inhibits histamine release and induces accumulation of secretory granules in rat basophilic leukemia cells.Method: We investigated the effect of five flavonoids: flavone, kaempferol, morin, myricetin, and quercetin at 1, 10, and 100 μm on proliferation and secretory mediator content (β‐hexosaminidase, histamine, and tryptase) in human leukemic mast cells (HMC‐1), the doubling time of which was about 2 d.Results: Flavone and kaempferol at 100 μm inhibited cell proliferation over 80% on either day 3, 4, or 5 of culture. Quercetin showed this level of inhibition only on day 5, myricetin inhibited by 50% at days 3–5, whereas morin's inhibition was <20%. All flavonoids (except morin) at 100 μm increased histamine and tryptase content, but not β‐hexosaminidase, equally at days 3 and 4 of culture quercetin also increased the development of secretory granules.Conclusion: These results indicate that certain flavonoids can inhibit HMC‐1 proliferation, induce secretory granule development and the accumulation of mediators.
Methods for Rapidly Measuring the Lodging Resistance of Wheat Cultivars
Authors: Berry P. M. , Spink J. , Sterling M. , Pickett A. A. 
Published: November 2003

AbstractLodging resistance ratings for winter wheat cultivars are frequently based upon observations of lodging. This is an unreliable method because of the frequent occurrence of years without significant lodging events. It also does not distinguish between stem and root lodging resistance. This paper describes the development and testing of instrumentation and procedures for two field‐based methods to rapidly assess stem and root lodging resistance. Both methods used a specifically designed instrument for measuring the resistance of shoots against rotational displacement. Stem lodging resistance was assessed when the soil was dry and strong, whereas resistance to root lodging was assessed after the soil had been weakened by irrigation. Tests were carried out on 14 winter wheat cultivars grown at two sites in the UK during 2002. Both methods were able to detect statistically significant differences between the cultivars for their resistance to stem and root lodging. A comparison of these results with observations of lodging in the field showed that the methods accounted for about 60 and 50 % of the stem and root lodging respectively.
Possible Residual Effects of Gibberellic Acid and Gibberellin Biosynthesis Inhibitors on Sprouting, Early Bulbil Formation and Tuber Yield in Chinese Yam
Authors: Kim S. K. , Lee S. C. , Kim K. M. , Lee B. H. , Lee I. J. 
Published: November 2003

AbstractThe residual effect of gibberellic acid (GA) and plant growth retardants [mepiquat chloride (MC) and trinexapac‐ethyl (TNE)], on Chinese yam plants was examined. Bulbil formation in MC and TNE‐treated tubers was earlier than that of the control and GA treatment. Bulbils in GA‐treated tubers increased the ratio of bulbil size (>4 mm) compared with the control. The highest GA treatment was fivefold more increased than that of the control. Bulbil yield per hectare was significantly increased by the elevated GA application compared with the control. The more MC concentration was elevated the more the ratio of bulbil size (>4 mm) increased. Bulbil yield was highest in the MC concentration (400 p.p.m.). The more TNE concentration was elevated the more the ratio of bulbil size (>4 mm) increased. Similar to MC treatment, TNE treatment showed the effect of bulbil enlargement in all the concentrations. This suggests that MC is the most effective growth retardant to induce bulbil enlargement and formation, and to increase bulbil and tuber yield in Chinese yams.
Membrane abnormalities and Ca homeostasis in muscles of the mdx mouse, an animal model of the Duchenne muscular dystrophy: a review
Authors: GILLIS J. M. 
Published: November 2003

Muscles of the mdx mouse lack dystrophin, a cytoskeletal protein. Mdx fibres exhibit an increased fragility to hypo‐osmotic shock and to forced lengthening, an abnormal opening time of stretch‐sensitive calcium channels. The question of a chronic elevated [Ca2+]i value is a matter of controversy.We have analysed Ca homeostasis in smooth and skeletal muscles from the adult mdx mouse. The wall of the vas deferens was loaded with the fluorescent Ca indicator Fura‐2‐AM (cell‐diffusible). Resting [Ca2+]i was measured after changes of the electrochemical potential for Ca2+ and after KCl or electrical stimulations. In no instance was a difference observed between these and similar muscles from control mice.Single striated fibres were isolated by collagenase treatment of the flexor digitorum brevis muscle and loaded with Fura‐2‐AM. The value of resting [Ca2+]i was measured using an in situ calibration procedure which took account of Ca buffering by Fura‐2. A chronic increase of cytosolic Ca2+ was not confirmed.The expression of the intracellular Ca‐binding protein, parvalbumin, was measured. It increased by about threefold in fast mdx muscles (tibialis anterior) but remained undetectable in the soleus. It is hypothesized that parvalbumin helps to maintain [Ca2+]i within normal values. This hypothesis will be discussed in connection with dystrophy phenotypes in mutant dogs and in human patients.
Ion transport in human skeletal muscle cells: disturbances in myotonic dystrophy and Brody's disease
Authors: BENDERS A. A. G. M. , WEVERS R. A. , VEERKAMP J. H. 
Published: November 2003

After excitation of skeletal muscle, the disturbed ion homeostasis is restored by Na+, K+ ATPase of the sarcolemma and Ca2+ ATPase of the sarcoplasmic reticulum (SR). Contrary to Na+, K+ ATPase, the concentration and isoenzyme distribution of SR Ca2+ ATPase in human skeletal muscle depend on fibre type and age. In cultured human muscle cells the concentration and activity of Na+, K+ ATPase and SR Ca2+ ATPase increase with maturation.In skeletal muscle and cultured muscle cells of patients suffering from myotonic dystrophy (MyD), the activity and the concentration of both Na+, K+ ATPase and SR Ca2+ ATPase are decreased by about 40%. In addition, we measured in cultured MyD muscle cells at rest an increased cytosolic Ca2+ concentration ([Ca2+]i) caused by active voltage‐operated Ca2+ channels, which are inactive in resting control cells. However, the restoration of a stimulus‐induced Ca2+ transient is unaffected. A differentiation‐related disturbance of membranes or a modulation defect of membrane proteins may play a role in MyD.In skeletal muscle and cultured muscle cells of patients suffering from Brody's disease, which is characterized by impaired muscle relaxation, the SR Ca2+ ATPase activity is reduced by about 50%, but the concentrations of total SR Ca2+ ATPase and the predominant SERCA1 isoform are normal. Diseased muscle cells show a delayed restoration of [Ca2+]i after stimulation, which might be explained by structural modifications of SERCA1. Reduction of the Ca2+ release by drugs balances the excitation–relaxation cycle of the pathological cells.
Local vascular responses to elevation of an organ above the heart
Authors: ASGEIRSSON B. , GRÄNDE P.‐O. 
Published: November 2003

Elevation of an organ above the heart reduces the arterial and venous hydrostatic pressures in proportion to the height of elevation. Intact autoregulation protects organs, such as the brain and skeletal muscle, from significant alterations in blood flow and hydrostatic capillary pressure due to the decrease in arterial inflow pressure during such a manoeuvre. However, the consequences of the decreased hydrostatic pressure on the venous side are far from clarified.The present study analyses the local haemodynamic effects of the decrease in arterial and venous hydrostatic pressures that occur during vertical elevation of an organ above the heart at atmospheric and raised tissue pressures (0, 10 and 30 mmHg). A sympathectomized cat skeletal muscle enclosed in a plethysmograph and perfused from the animal was used as the experimental model.The results show that elevation of the muscle above the heart at atmospheric tissue pressure created a variable vascular resistance starting at the venous outlet of the organ, and related to the difference between tissue pressure and venous outflow pressure. This resistance completely protects the organ from the hydrostatic pressure alterations on the venous side. The results also show that arterial pressure variations will exert the same haemodynamic influences on the organ as tissue pressure variations, except for the formation of the venous outflow resistance at raised tissue pressure.The application of these results to normal and injured organs, e.g. normal and injured skeletal muscle and brain, with various tissue pressures, is discussed.