bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxygen in Wound Healing and Infection
Authors: Gottrup Finn 
Published: March 2004

AbstractIt is a fundamental clinical observation that wounds do not heal in tissue that does not bleed, and they almost always heal in tissue that bleeds extensively. Continuous supply of oxygen to the tissue through microcirculation is vital for the healing process and for resistance to infection. Evaluation of tissue perfusion and oxygenation is important in all types of wound patients. Monitoring systems should measure the hemodynamic situation and the ability of the cardiovascular system to deliver an adequate volume of oxygen to meet the metabolic demands of the peripheral tissue. Oxygen therapy is important in relation to both healing and resistance to infections. External factors have been shown to significantly decrease the peripheral oxygen supply, and supplementary perioperative oxygen to reduce the surgical wound infection rate by one‐ half in patients undergoing colorectal resection. Hyperbaric oxygen therapy may be beneficial in situations where the nutritive flow and oxygen supply to the healing tissue are compromised by local injury, and particularly if anaerobic infection is present. However, the definitive proof for the effect and indications of this therapy in wound healing still has to be established. It can be concluded that adequate delivery of oxygen to the wound tissue is vital for optimal healing and resistance to infection. Assessment of perfusion and oxygenation is essential for the wound patient, as well as the treating personnel. The indication for hyperbaric oxygen treatment still needs to be defined. During wound healing the continuity and function of the damaged tissue are re‐established. This is only possible through a restoration of the microcirculation and thereby the nutrition to the tissue. The main component of the nutrition is oxygen, which is critically important for healing a wound by production of granulation tissue and for ensuring resistance against infection. This has been shown experimentally, but recently a short period of supplementary oxygen has been shown to decrease wound complications in clinical practice as well.
Oxygen in Wound Healing—More than a Nutrient
Authors: Tandara Andrea A. , Mustoe Thomas A. 
Published: March 2004

AbstractThis article provides an overview of the role of oxygen in wound healing. The understanding of this role has undergone a major evolution from its long‐recognized importance as an essential factor for oxidative metabolism, to its recognition as an important cell signal interacting with growth factors and other signals to regulate signal transduction pathways. Our laboratory has been engaged in thestudy of animal models of skin ischemia to explore in vivo the impact of hypoxia as well as the use of oxygen as a therapeutic agent either alone or in combination with other agents such as growth factors. We have demonstrated a synergistic effect of systemic hyperbaric oxygen and growth factors that has been substantiated by Hunt’s group. Within the past 10 years research in the field of wound healing has given new insight into the mechanism of action of hypoxia and hyperoxia as modifiers of the normal time‐course of wound healing. The article concludes with a discussion of why hypoxia and hyperoxia intercurrently play an important role in wound healing. Hypoxia‐inducible factor 1 is crucial in that interplay.
Clinical Hyperbaric Oxygen Therapy, Wound Perfusion, and Transcutaneous Oximetry
Authors: Niinikoski Juha H.A. 
Published: March 2004

AbstractHyperbaric oxygen therapy (HBOT) is an important adjunct in the management of problem wounds which exist in chronic oxygen deficiency and in which the local oxygen tension is below optimal for healing. In the treatment of hypoxic and ischemic wounds, the most important effects of hyperbaric oxygenation are the stimulation of fibroblast proliferation and differentiation, increased collagen formation and cross‐linking, augmented neovascularization, and the stimulation of leukocyte microbial killing. Ischemic soft tissues also benefit from hyperoxygenation through improved preservation of energy metabolism and reduction of edema. Hyperbaric oxygen is administered in either a multiplace or a monoplace hyperbaric chamber. Normally, pressures of 2 to 2.5 ATA are used for a period of 90 minutes once or twice daily. For an objective assessment of wound perfusion and oxygenation, transcutaneous oximetry provides a simple, reliable, noninvasive, diagnostic technique. It can be used for assessment of tissue perfusion in the vicinity of the problem wound. Transcutaneous oximetry may be used in the assessment of wound healing potential, selection of amputation level, and patient selection for HBOT. In diabetic patients with chronic foot ulcers peri‐wound transcutaneous oxygen tensions (TcPo2) over 400 mmHg in 2.5 ATA hyperbaric oxygen or over 50 mmHg in normobaric pure oxygen predict healing success with adjuncted HBOT with high accuracy.
Development of a Wound Dressing Targeting Neutrophil Function
Authors: Nygren Håkan , Malmberg Per , Sahlin Herman 
Published: March 2004

AbstractEarlier studies show that neutrophils are virtually unable to kill Staphylococcus aureus in vitro. However, upon addition of 10 mM N‐acetylcysteine (NAC) or reduced glutathione (GSH) the neutrophil bacterial killing ability becomes excellent. We want to exploit this phenomenon to develop a wound dressing material that will improve neutrophil function. To study the mechanisms behind the downregulation of neutrophil elimination of bacteria, we used different markers for neutrophil function on surface‐adhering neutrophils in contact with S. aureus with or without addition of the antioxidants NAC or GSH. Analysis by scanning electron microscopy showed cell shrinkage and numerous cytoplasmic processes on surface‐adhering neutrophils exposed to S. aureus. In cells exposed to S. aureus and GSH, the cells were of normal size and the cytoplasm was spread as in normal attachment. Staining for intracellular GSH, a hallmark of oxidative stress, showed little difference between the experimental groups, indicating that the cells were not damaged by traditional oxidative stress. The H2O2 production of neutrophils, measured by Amplex red, was correlated to bacterial exposure and was not affected by the addition of scavengers. The intracellular and extracellular production of ROS was measured by luminol‐amplified chemiluminescence. The apparent ROS‐production was mostly intracellular and decreased in the presence of scavengers. However, extracellular production of ROS was not affected by the addition of NAC. The production of nitric oxide (NO) was measured spectrophotometrically as the production of nitrate apparently decreased in the presence of scavengers, probably as a result of interference with the reagents in the test system. In conclusion, differences between leukocytes that were able to eliminate S. aureus and those that were not were mainly seen in the morphology of the cells and in cell viability. The morphological findings point to a difference in NO signaling in the absence and presence of ROS scavengers.
Reactive Oxygen Species and EGR‐1 Gene Expression in Surgical Postoperative Peritoneal Adhesions
Authors: Roy Sashwati , Clark Clancy J. , Mohebali Khashayar , Bhatt Udayan , Wallace William A. , Nahman N. Stanley , Ellison E. Christopher , Melvin W. Scott , Sen Chandan K. 
Published: March 2004

AbstractPostoperative peritoneal adhesions are common and serious complications of general abdominal and gynecological surgery that can lead to chronic abdominal pain, small‐bowel obstruction and infertility. The specific pathophysiology of peritoneal adhesions remains elusive and current treatment is relegated to prevention through meticulous surgical technique and protective physical barriers, gels and solutions. We have reported that reactive oxygen species (ROS), generated by phagocytic cells at the site of tissue injury, serve as major signaling molecules regulating the expression of vascular endothelial growth factor (VEGF) and subsequent wound repair. We hypothesized that peritoneal adhesions are a product of over‐healing surgical wounds and that, like in wound healing, ROS are implicated in their pathogenesis. We examined the presence of footprints of ROS and the ROS‐inducible angiogenic factor VEGF in human adhesion tissue. An experimental model of peritoneal adhesion was established in rodents to study of the dynamics of ROS‐induced gene expression during de novo adhesion tissue formation. Immunohistochemical analysis demonstrated presence of ROS/oxidant and macrophages in human peritoneal tissue. The presence of ROS and ROS‐sensitive transcription factor EGR‐1 was also evident in an experimental rodent peritoneal adhesion model. Along with ROS, VEGF, and a large number of mature and immature CD31/vWF positive blood vessels were present in the adhesion tissue. These observations are not consistent with the contention that adhesions are non‐functional scar tissue. The newly developed rodent model of adhesion may present a useful approach to reproducibly and objectively study molecular mechanisms underlying the dynamic process of de novo adhesion tissue formation.
Experimental Models of Stress and Wound Healing
Authors: Sheridan John F. , Padgett David A. , Avitsur Ronit , Marucha Phillip T. 
Published: March 2004

AbstractExperimental animal models have been used to examine stress‐induced interactions among the nervous, endocrine, and immune systems. Generally, the response to stress results in a body‐wide set of physiologic adaptations, mediated through the activation of neuroendocrine pathways that intersect and modulate inflammatory and immune responses. These interacting responses modulate diverse physiological processes including the initiation of tissue repair and wound healing. Two different stressors were used to activate neuroendocrine responses to study their impact on wound healing: restraint (RST) and social disruption (SDR). Previous studies showed that both stressors activate the hypothalamic‐pituitary‐adrenal (HPA) axis, resulting in elevated plasma levels of the corticosterone (cort) response and modulation of pro‐inflammatory cytokine response. To test the effects of stress‐induced HPA activation on inflammatory responses and wound healing, a 3.5‐mm cutaneous punch biopsy wound was placed on the dorsal surface of control and stressed (RST or SDR) C57BL/6 male mice and the kinetics of wound healing were studied over 10 days. RST slowed wound healing in inbred C57BL/6 mice, whereas the wounds on SDR mice healed in a fashion similar to the non‐stressed, home cage controls.
Oxygen: At the Foundation of Wound Healing—Introduction
Authors: Hunt Thomas K. , Ellison E. Christopher , Sen Chandan K. 
Published: March 2004

Abstract“Wound Healing: Oxygen & Emerging Therapeutics” Columbus, Ohio, September 12–15, 2002. Sponsored by the National Institutes of Health (R13AR049171), International Union of Biochemistry & Molecular Biology and UNESCO‐Global Network of Molecular & Cell Biology. Conference co‐chairs: Chandan K. Sen, the Ohio State University Medical Center and Thomas K. Hunt, University of California‐ San Francisco. This congress was conceived for two reasons: to consolidate what is known about oxygen in the repair process and to stimulate discussion about new developments of control of healing by redox regulated signaling processes. A historical and evolutionary perspective on the role of oxygen in wound healing—from the classical physiology of oxygen in the wound to the refined concept of redox signaling— is presented.
What caused the decline of the Lake IJsselmeer eel stock after 1960?
Authors: Dekker Willem 
Published: March 2004

Abstract
The European eel (Anguilla anguilla L.) is in severe decline: landings from and recruitment to the stock have fallen off since the mid-1960s and the early 1980s, respectively. Several hypotheses on the causes of the decline in recruitment have been advanced, some predicting an earlier decline of the adult stock. In order to narrow the range of potential hypotheses, this paper contrasts current ones with trends in abundance and length distribution of the local stock in Lake IJsselmeer (the Netherlands) over the period of the decline. The data set consists of research surveys, market sampling, gear development experiments, etc., since 1904, and is uninterrupted since 1950. A statistical analysis is designed in which sampling characteristics (length selectivity of gears and of mesh sizes, and sample selection procedures) are separated out of trends in the local stock over the years (abundance, length composition). The decline of the Lake IJsselmeer stock started in 1960, affected exploited and undersized eels, and was steeper for larger eels. The abundance of the smallest size class in the lake matches the independently recorded recruitment strength, which did not decline before 1980. Excessive exploitation, habitat loss, barriers to migration, introduced parasites, and changes in ocean climate cannot explain the observed trends when taken individually. Therefore, the cause of the decline of the local stock in Lake IJsselmeer is still a mystery and, because the historical information is limited and cannot be added to, is likely to remain so.
Comparing the modelled and measured target-strength variability of walleye pollock, Theragra chalcogramma
Authors: Hazen Elliott L. , Horne John K. 
Published: March 2004

Abstract
Many biological and physical factors potentially affect target strength. While these sources have been identified, few studies have compared the relative effects of individual factors. Modelled and measured target strengths in non-dimensional metrics were used to compare and rank the effects of fish length, tilt, depth, and acoustic frequency on backscatter intensity. Ex situ measurements of target strength were used to examine the effects of tilt and depth and then compared to backscatter model predictions. Swimbladder volume reduction due to increasing pressure at depth was modelled using Boyle's law and by varying the ratio of dorsal to lateral compression. We found that length has the largest effect on the modelled and measured backscatter intensity, followed by tilt, frequency, and depth. Including tilt distributions in backscatter estimates improved the match between empirical target-strength measures and model predictions. Non-dimensional influence ratios provide insight into the sources and magnitudes of the backscatter variability.
Modulation of trigeminal sensory neuron activity by the dual cannabinoid–vanilloid agonists anandamide, N‐arachidonoyl‐dopamine and arachidonyl‐2‐chloroethylamide
Authors: Price Theodore J , Patwardhan Amol , Akopian Armen N , Hargreaves Kenneth M , Flores Christopher M 
Published: April 2004

Peripheral cannabinoids have been shown to suppress nociceptive neurotransmission in a number of behavioral and neurophysiological studies. It is not known, however, whether cannabinoids exert this action through direct interactions with nociceptors in the periphery and/or if other processes are involved. To gain a better understanding of the direct actions of cannabinoid‐vanilloid agonists on sensory neurons, we examined the effects of these compounds on trigeminal ganglion (TG) neurons in vitro.
AEA (EC50=11.0 μM), NADA (EC50=857 nM) and arachidonyl‐2‐chloroethylamide ACEA (EC50=14.0 μM) each evoked calcitonin gene‐related peptide (CGRP) release from TG neurons. The TRPV1 antagonists iodo‐resiniferatoxin (I‐RTX) and capsazepine (CPZ) each obtunded AEA‐, NADA‐, ACEA‐ and capsaicin (CAP)‐evoked CGRP release with individually equivalent IC50's for each of the compounds (I‐RTX IC50 range=2.6–4.0 nM; CPZ IC50 range=523–1140 μM).
The pro‐inflammatory mediator prostaglandin E2 significantly increased the maximal effect of AEA‐evoked CGRP release without altering the EC50. AEA, ACEA and CAP stimulated cAMP accumulation in TG neurons in a calcium‐ and TRPV1‐dependent fashion. Moreover, the protein kinase inhibitor staurosporine significantly inhibited AEA‐ and CAP‐evoked CGRP release.
The pungency of AEA, NADA, ACEA and CAP in the rat eye‐wipe assay was also assessed. Interestingly, when applied intraocularly, NADA or CAP each produced nocifensive responses, while AEA or ACEA did not.
Finally, the potential inhibitory effects of these cannabinoids on TG nociceptors were evaluated. Neither AEA nor ACEA decreased CAP‐evoked CGRP release. Furthermore, neither of the cannabinoid receptor type 1 antagonists SR141716A nor AM251 had any impact on either basal or CAP‐evoked CGRP release. AEA also did not inhibit 50 mM K+‐evoked CGRP release and did not influence bradykinin‐stimulated inositol phosphate accumulation.
We conclude that the major action of AEA, NADA and ACEA on TG neurons is excitatory, while, of these, only NADA is pungent. These findings are discussed in relation to our current understanding of interactions between the cannabinoid and vanilloid systems and nociceptive processing in the periphery.

British Journal of Pharmacology (2004) 141, 1118–1130. doi:10.1038/sj.bjp.0705711
Technochange Management: Using IT to Drive Organizational Change
Authors: Markus M Lynne 
Published: March 2004

Using IT in ways that can trigger major organizational changes creates high-risk, potentially high-reward, situations that I call technochange (for technology-driven organizational change). Technochange differs from typical IT projects and from typical organizational change programs and therefore requires a different approach. One major risk in technochange—that people will not use information technology and related work practices—is not thoroughly addressed by the discipline of IT project management, which focuses on project cost, project schedule, and solution functionality. Organizational change management approaches are also generally not effective on their own, because they take as a given the IT “solutions” developed by a technical team. Consequently, the potential for the IT “solution” to be misaligned with important organizational characteristics, such as culture or incentives, is great. Merely combining IT project management and organizational change management approaches does not produce the best results, for two reasons. First, the additive approach does not effectively address the many failure-threatening problems that can arise over the lengthy sequential process of the typical technochange lifecycle. Second, the additive approach is not structured to produce the characteristics of a good technochange solution: a complete intervention consisting of IT and complementary organizational changes, an implementable solution with minimal misfits with the existing organization, and an organization primed to appropriate the potential benefits of the technochange solution. With hard work and care, the combined IT project management plus organizational change approach can be made to work. However, an iterative, incremental approach to implementing technochange can be a better strategy in many situations. The essential characteristic of the technochange prototyping approach is that each phase involves both new IT functionality and related organizational changes, such as redesigned business processes, new performance metrics, and training.
The relationship between plasma levels of leptin and androgen in healthy and preeclamptic pregnant women
Authors: Atamer Yildiz , Erden Ali Ceylan , Demir Bulent , KoÇyigit Yuksel , Atamer AytaÇ 
Published: April 2004

Background.  To clarify the role of leptin and androgens in the pathogenesis of preeclampsia, we wanted to assess role of maternal leptin in women with severe and mild preeclampsia and the effects of sex steroid hormones on leptin production.Methods.  The groups consisted of 40 healthy pregnant women (HPW) as well as 55 pregnant women with severe preeclampsia (SPE) and 41 pregnant women with mild preeclampsia (MPE). No significant differences were observed between the three groups regarding age, gestational age and body mass index (BMI). Plasma leptin, total testosterone (T), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS) and androstenedione (A) levels were measured. Statistical analysis was achieved with one‐way analysis of variance (anova) followed by post hoc multiple comparisons with the Tukey honestly significant difference (HSD) test by using SPSS for Windows statistical computer program, and the Pearson's coefficient of correlation was calculated.Results.  The plasma level of leptin was significantly increased in the SPE and MPE groups (p < 0.001), whereas the plasma level of T was significantly increased only in the SPE group (p < 0.001). However, there was no significant difference in plasma levels of DHEAS among the three groups (p < 0.05). The plasma level of A was significantly decreased in the MPE group (p < 0.05). There was no significant difference in the plasma level of E2 in the MPE and SPE groups (p < 0.05). There was a significant positive correlation between the plasma levels of leptin and E2 in the MPE group (r = 0.41, p < 0.001).Conclusion.  We concluded that the elevated plasma levels of leptin and testosterone could contribute to the endothelial dysfunction involved in the pathogenesis of preeclampsia, and that estradiol might lead to an increase in the plasma levels of leptin.
Questionnaire survey on the use of rotary nickel–titanium endodontic instruments by Australian dentists
Authors: Parashos P. , Messer H. H. 
Published: March 2004

AbstractAim  To ascertain the extent of the adoption and use of rotary nickel–titanium (NiTi) instruments and techniques in general dental practice and specialist endodontic practice in Australia in 2001.Methodology  A questionnaire survey comprising 43 questions was developed by first creating questions, then pilot testing with 10 postgraduate students in endodontics, followed by a final revision. The final series of questions covered demographics, patterns of rotary NiTi usage, issues associated with NiTi usage and training in NiTi use. The sampling frame was 908, comprising 64 endodontists and 844 general dentists.Results  The overall response rate was 87%. Rotary NiTi instruments were used by 22% of general dentists and 64% of endodontists. The two main reasons for not using rotary NiTi were ‘no perceived advantage’ and ‘too fragile’. Instrument fracture had been experienced by 74% of respondents, and 72% of these had fractured one to five files for the two main perceived reasons of ‘excessive pressure on the file’ and ‘over‐usage’. The next two most common problems encountered were ‘binding’ (53%) and ‘ledging’ (45%). Very high proportions of positive experiences were noted. Most respondents (73%) had attended one or more continuing education courses, most of which were provided by dental supply companies (64%).Conclusions  The results indicate a sensible and responsible approach to the incorporation of rotary NiTi instruments and techniques into root canal treatment. Dentists were aware of the limitations of the new technology, but were taking steps to become familiar with the properties and behaviour of the instruments. Instrument fracture was common, but it was of low frequency and did not deter dentists from using the technology.