bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancing user involvement through interprofessional education in healthcare: the case of cancer services
Authors: Daykin Norma , Rimmer J. , Turton P. , Evans S. , Sanidas M. , Tritter J. , Langton H.
Published: March 2003

Recent developments in UK health policy seek to place the service user at the centre of service delivery, although user involvement is a complex and challenging process. This paper explores the contribution of interprofessional (IP) education to user involvement, focusing on education and training within a UK cancer network. The impact of participation in educational projects on users is explored and the benefits and limitations of IP education are discussed. Triangulation of data from several sources suggests that the contribution of IP education to user involvement is contingent on professional constructions, which include ethical positions that are related closely to issues of power and control. In particular, professional protectionism may represent an ongoing difficulty in user involvement research and development. The research suggests that without dedicated support and training, some professionals are unlikely to engage willingly with involving users in service development.
Influence of environmental variability on the growth of Lilac‐crowned Parrot nestlings
Authors: Renton Katherine
Published: March 2003

Growth rate parameters were analysed for Lilac‐crowned Parrot Amazona finschi nestlings in the tropical dry forest of the Reserva de la Biosfera Chamela‐Cuixmala, Mexico. Growth rates for psittacine species follow the inverse relation with body mass observed for neotropical landbirds, with larger parrot species exhibiting slower growth rates. There was significant variation between years in size and growth rates of Lilac‐crowned Parrot nestlings with nestlings exhibiting slower growth rates in 1996 than in 1997. Food abundance for parrots also varied significantly between years, with greater food availability during the 1997 breeding season than that of 1996. The increased size and growth rates of nestlings in 1997 may have reflected this, and suggests the potential influence of environmental variability on parrot reproduction, particularly in such a markedly seasonal habitat.
Brood size and body condition in the House Sparrow Passer domesticus: the influence of brooding behaviour
Authors: Chastel Olivier , Kersten Marcel
Published: March 2003

In many bird species, females undergo a marked decline in body condition during the first days of the nestling period. This decline may be because brooding young chicks reduces the time available for foraging. Alternatively, it might be viewed as an adaptive way to reduce flight costs when the food demand of the brood is highest. To test these hypotheses we modified the brooding commitment of House Sparrows Passer domesticus by manipulating brood size to see if changes in time spent brooding affects adult body condition. During the nestling period, females provided on average three times as much brooding as males. Reduced broods received 14% more brooding than large broods and time spent brooding declined with brood size and chick age according to an exponential decay function. Male body condition was unaffected by brood size and remained stable throughout the reproductive period. Body condition of females with enlarged broods decreased gradually during the nestling period, whereas that of females tending reduced broods dropped abruptly and significantly upon hatching. This resulted in females with reduced broods having lower body condition during the first half of the nestling period than those with enlarged broods. The sharp drop in body condition of females with reduced broods coincided with the period that brooding was most intensive. Indeed, female body condition at the end of the nestling period was negatively correlated with the proportion of time they spent brooding during the first half of the nestling period. Thus, the probable lower homeothermic capacities of reduced broods implies a higher brooding commitment for female House Sparrows that, in turn, may reduce their opportunity to forage and consequently also their body condition.
Increase in frequency of the bridled morph of the Common Guillemot Uria aalge on the Isle of May, 1946–2000: a return to former levels?
Authors: Harris M. P. , Rothery P. , Wanless S.
Published: March 2003

Bridling in the Common Guillemot Uria aalge is a classic example of a stable ratio‐cline polymorphism. Between 1946 and 2000 the frequency of the bridled morph of the Common Guillemot colony on the Isle of May, south‐east Scotland, increased significantly from 3.5% to 5.9%. Demographic data collected between 1982 and 2000 indicated that the average breeding success of a pair including at least one bridled bird was 83.8%, significantly greater than 79.5% in unbridled pairs. Over the same period the average overwinter survival was 96.3% for bridled birds and 94.7% for unbridled birds, but the difference was not statistically significant. A population model showed that the increase in frequency of bridling could be accounted for as a return to an equilibrium level close to the 5.04% observed in 1936. Differences in breeding success contributed relatively little to the increase, which could be explained without recourse to differential selection pressure. The latitudinal variation in bridling suggests that bridled morphs are more cold tolerant than unbridled ones. However, the increase in the frequency of bridled birds on the Isle of May was not associated with any decrease in sea or air temperatures over the period.
Impact of nest‐trapping and radio‐tagging on breeding Golden Eagles Aquila chrysaetos in Argyll, Scotland
Authors: Gregory M. J. P. , Gordon A. G. , Moss R.
Published: March 2003

Golden Eagles Aquila chrysaetos in South Argyll, Scotland, have been monitored annually since 1964. Other workers trapped and radiotagged breeding adults there for a separate study during 1991–1996. Our analysis of our monitoring data shows that the trapping and tagging was followed by reduced reproductive success (proportion of territories producing young each year). Also, nest‐sites where adults had been trapped were used less frequently after the trapping.
Automatic Classification of Acoustic Emission Patterns
Authors: Rippengill S. , Worden K. , Holford K. M. , Pullin R.
Published: March 2003

Abstract: The problem of automatic classification of acoustic emission signals using techniques derived from pattern recognition is addressed in this paper. The data were taken from laboratory experimental work on a box girder of a bridge in which the acoustic emission (AE) generation mechanism and location were monitored. Two statistical methods and a neural network procedure have been used to classify the data into groups representing different AE generation mechanisms. The classifiers are constructed using the traditional AE features – four parameters from each burst. Principal component analysis is used to reduce the dimension of the AE data feature vectors to two dimensions, resulting in simple visualisations of the data.
The effect of under and over refractive correction on visual performance and spectacle lens acceptance
Authors: Atchison David A. , Schmid Katrina L. , Edwards Katie P. , Muller Sharon M. , Robotham Jayne
Published: March 2003

As a follow‐on from a previous study by Miller, Kris and Griffiths (1997, Optom. Vis. Sci.84, 521–526), we investigated the effect of small prescription errors on spatial visual performance and spectacle lens acceptability. We included both negative and positive errors and binocular and monocular errors. Data were collected on 15 young adult subjects. Clinical measures were taken of pupil size, ocular dominance, binocular visual acuity, negative and positive relative accommodation, distance and near heterophorias, and stereopsis. Visual performance was measured with the best correction and for ±0.50 D spherical binocular and monocular errors. Subjects wore spectacles, each containing a different error in turn, for 2 days and compared them with a reference pair. Following the wearing period subjects assessed the performance of the spectacles by completing a short questionnaire. The only ocular tests for which these small prescription errors had significant effects were binocular visual acuity and negative relative accommodation. No significant relationship was observed between any of the clinical test results and overall lens acceptance. Despite this, the reference pair was generally perceived as better than the test pairs containing errors, and a considerable proportion of subjects reported pairs with errors as being unacceptable. In conclusion, the questionnaire findings support the need for both accurate monocular and binocular refractions. Subjects differed in their criteria for judging lens acceptability.
Optometrists' examination and referral practices for patients presenting with flashes and floaters
Authors: Alwitry A. , Chen H. , Wigfall S.
Published: March 2003

Introduction: Patients experiencing flashes and floaters commonly present to their optometrist. Some of these patients may have significant pathology, yet there is a great deal of variability with regard to examination technique and referral practice.

Methods: A questionnaire survey was undertaken to determine the current management of patients presenting to their optometrist with flashes and floaters. All practising community optometrists within Southern Derbyshire received a questionnaire and 74 (56.9%) completed replies were received.

Results: Optometrists estimated that an average of 14 patients per month per optometrist presented with symptoms of flashes and/or floaters. Mydriasis was utilised routinely for examination in approximately half of the patients. Mean relative confidence was 2.0 at identifying a vitreous haemorrhage and 6.5 for vitreous pigment (complete confidence = 0, complete lack of confidence = 10). Eight percent of responders were unfamiliar with the clinical sign of vitreous pigment, and 17% identifying this sign did not refer all such patients to the hospital services.

Conclusions: Patients presenting to their optometrists with flashes and/or floaters make up a sizeable part of the community optometrist's workload and the management of these patients is highly variable. A large proportion of these patients are examined without mydriasis, even in the presence of various risk factors for retinal detachment. There is a relative lack of confidence amongst optometrists with regards the detection of vitreous pigment and the prognostic implications of this finding. Educational measures such as study days may help the level of understanding and heighten the appreciation of the implications of flashes and floaters and the various clinical signs encountered.
Effect of β‐adrenoceptor antagonists on autonomic control of ciliary smooth muscle
Authors: Winn Barry , Culhane Helena M. , Gilmartin Bernard , Strang Niall C.
Published: March 2003

Abstract Purpose: Pharmacological intervention with peripheral sympathetic transmission at ciliary smooth muscle neuro‐receptor junctions has been used against a background of controlled parasympathetic activity to investigate the characteristics of autonomic control of ocular accommodation.

Methods: A continuously recording infra‐red optometer was used to measure accommodation on a group of five visually normal emmetropic subjects under open‐ and closed‐loop conditions. A double‐blind protocol between saline, timolol and betaxolol was used to differentiate between the localised action on ciliary smooth muscle and effects induced by changes in stimulus conditions. Data were collected before and 45 min following the instillation of saline, timolol or betaxolol. Open‐loop post‐task decay was investigated following 3 min sustained near fixation of a stimulus placed 3 D above the subject's pre‐task tonic accommodation level. Closed‐loop dynamic responses were recorded for each treatment condition while subjects viewed sinusoidally (0.05–0.6 Hz) or stepwise vergence‐modulated targets over a 2 D range (2–4 D).

Results: Open‐loop data demonstrate a rapid post‐task regression to pre‐task tonic accommodation levels for saline and betaxolol control conditions. A slow positive post‐task shift was induced by timolol indicating that sympathetic inhibition contributes to accommodative adaptation during sustained near vision. Closed‐loop accommodation responses to temporally modulated sinusoidal stimuli showed characteristic features for both saline and betaxolol control conditions. Timolol induced a reduced gain for low‐ and mid‐temporal frequencies (< 0.3 Hz) but did not affect the response at higher temporal frequencies. Response times to stepwise stimuli increased following the instillation of timolol for the near‐to‐far fixation condition compared with the controls and was related to the period of sustained prior fixation.

Conclusions: Modulation of accommodation under open‐ and closed‐loop conditions by a non‐selective β‐blocker is consistent with the temporal and inhibitory features of sympathetic innervation to ciliary smooth muscle. Although parasympathetic innervation predominates there is evidence to support a role for sympathetic innervation in the control of ocular accommodation.
Vision status of children with oculocutaneous albinism
Authors: Oduntan A. O. , Raliavhegwa M. , Lund P. M.
Published: March 2003

Purpose:  Black South African children with oculocutaneous (OCA) albinism were examined optometrically to establish the level of vision improvement that could be achieved following optical correction.

Methods:  The children (N = 153) (males 50.3%; females 49.7%), aged 7–17 years (mean = 10.76 ± 2.25 years) were examined with a logMAR VA chart, cover tests, retinoscopy (dry), subjective refraction, Vistech contrast sensitivity test, ophthalmoscopy, Randot stereotest, Ishihara and Farnsworth Panel D‐15 tests.

Results:  Many (34.6%) of the children had strabismus, 2–25 prism dioptres. Uncorrected distance VAs were: OD: Finger counting (FC) to 6/7.5 − 2, OS: 6/7.5 + 2 to 6/7.5 − 3, OU: 6/60 − 1 to 6/7.5. Most (67.6%) of the children had myopia. Others (30.8%) had hyperopia or emmetropia (1.7%). Astigmatism was present in 92.25% of the children. The nearest equivalent spherical powers were: OD: −12.00 to +2.75 D (mean = −1.48 ± 2.28 D) and OS: −8.00 to +5. 75 D (mean = 1.36 ± 2.18 D).

Following optical correction, VA improvement ranged from one to three lines in 71.2% of the children. The corrected VAs were, OD FC to 6/6 − 1, OS 6/7.5 + 2 to 6/6 − 1, and OU 6/60 to 6/6. Many (84.3%) of the children had corrected VA worse than 6/18 in the better eye and were therefore classified as partially sighted or blind (VA worse than 3/60). Stereoacuity was poor (500–70 sec arc) in most (89.5%) of the children, whilst others could not perceive the minimum 500 sec arc on the test. Contrast sensitivity was poor, maximum spatial frequency being 18 cpd with peak sensitivity at 3 cpd. Many (83%) of the children, however, had normal colour vision.

Conclusion:  These children with OCA had poor VA, which could be improved significantly with optical correction. Their poor contrast sensitivity and depth perception, however, were not improved. Most of the children with OCA had normal colour vision.
The effect of changing from glasses to soft contact lenses on myopia progression in adolescents
Authors: Fulk George W. , Cyert Lynn A. , Parker Donald E. , West Roger W.
Published: March 2003

At the end of a clinical trial of bifocals as myopia treatment, subjects were allowed to select any type of optical correction they wished and were asked to return in 1 year. This report gives results of that last examination with emphasis on how progression rates differed between those remaining in their original type of glasses compared with those who switched to soft contact lenses. We found that myopia progressed at an age‐adjusted average rate of 0.74 D in 19 children who switched to soft contact lens wear compared with 0.25 D for 24 children remaining in glasses (p < 0.0001). Increased growth of the vitreous chamber appeared to account for much of this excess myopia progression, although the difference in that variable did not reach statistical significance (p = 0.101). We also noted a 0.203 D steepening in the corneal curvature in contact lens wearers compared with spectacle wearers whose corneas steepened very little (0.014 D, p = 0.007). Soft contact lens wear was also accompanied by a greater change in the near‐point phoria which moved 4.5 prism dioptres in the exo direction compared with spectacle wearers who experienced only a 1.4 prism dioptre divergent shift (p = 0.048).
Does Omeprazole Cause Fat Malabsorption?
Authors: Smith Brian S. , Summa Maria A.
Published: March 2003

Abstract Gastric acid and peristaltic movements are two major mechanisms in preventing bacterial overgrowth of the upper gastrointestinal tract. Reduced acid secretions and/or altered peristalsis can disrupt normal flora and may result in bacterial overgrowth. Bacterial overgrowth can lead to malabsorption of fats and other nutrients. Fat malabsorption is thought to occur due to overgrowth of bile deconjugating anaerobic organisms. Bile acids are necessary for proper fat absorption; when organisms deconjugate bile acids, fat malabsorption may occur. Acid‐reducing drugs such as omeprazole have been implicated in causing bacterial overgrowth of the upper gastrointestinal tract. Most studies indicate that omeprazole treatment causes an overgrowth primarily of normal swallowed flora that are not capable of deconjugating bile acids, though a few studies do suggest that overgrowth of anaerobes and bile acid deconjugation does occur. At this time, the role of omeprazole as a cause of fat malabsorption is not clear. More studies are needed to determine the extent and clinical significance of omeprazole‐induced fat malabsorption.
What the Primary Physician Needs to Know About Home Parenteral Nutrition
Authors: Howard Lyn
Published: March 2003

Abstract This review outlines the history of home parenteral nutrition (HPN), elements needed for proper selection of patients, and clinical outcomes that can be anticipated with different diagnoses and age groups. It discusses potential infections and metabolic and mechanical complications and describes the professional expertise needed to make HPN a safe, viable undertaking. Patient and family training are described, and the importance of linking the patient to a support organization and other HPN families is emphasized. A national support network for patients and families is available through the Oley Foundation, Albany Medical College, Albany, NY 12208. The potential role of small bowel transplant is reviewed. Currently, prognosis is better on HPN, but this may change as transplant techniques improve. Since 24‐hour professional help must be available to HPN patients, primary physicians may opt to use a nutrition support specialist. The specialist should be responsible for maintaining a patient's chronic venous access, recognizing complications, and making interval adjustments in the therapy. A referral to a nutrition support specialist is particularly recommended if the course of HPN is likely to be years, not just months.
Nutritional Assessment of the Oral Cavity
Authors: Deen Darwin
Published: March 2003

The oral cavity reflects the general state of health of the patient. A thorough examination of the oral cavity will provide clinicians with information important to assessment of the patient. Through this exam, clinicians can diagnose specific oral diseases and relevant vitamin and mineral deficiencies or toxicities. This article reviews the appropriate procedures for examination of the mouth, tongue, teeth, and gums and discusses various abnormalities and their potential etiologies. It includes case examples illustrative of patients who might present to a primary care practice.
Selenium, an Antioxidant Nutrient
Authors: Burk Raymond F.
Published: March 2003

Selenium is an essential constituent of a number of enzymes, some of which have antioxidant functions. Deficiency of the element in animals makes them susceptible to injury by certain types of oxidative stress. At least 1 human disease occurs only in selenium‐deficient individuals. Therefore, it seems prudent to avoid selenium deficiency. The plasma (or serum) selenium concentration is often used to assess selenium nutritional status. A plasma selenium concentration of 8 μg/dL or greater in a healthy subject indicates that plasma selenoproteins are optimized and the subject is selenium replete. The Third National Health and Nutrition Examination Survey determined plasma selenium in 17,630 subjects in the United States. Its results indicate that more than 99% of the subjects studied were selenium replete. The Institute of Medicine has set the Recommended Dietary Allowance for selenium at 55 μg per day for adults. Since most estimates of selenium intake in the United States are 80 μg per day or greater, routine selenium supplementation is not recommended in the United States.
Diabetic foot ulcers: A framework for prevention and care
Authors: Boulton Andrew J , Meneses Patricio , Ennis William J
Published: March 2003

Complications secondary to diabetes, such as diabetic foot ulcers, continue to be a major worldwide health problem. At the same time, health care systems are changing rapidly, causing concern about the quality of patient care. While the ultimate effect of current changes on health care professionals and patient outcomes remain uncertain, measures commonly used to reduce costs, e.g., disease and multi discliplinary management strategies, have been shown to help prevent the occurrence of diabetic ulcers. In addition, ultilizing a multi discliplinary approach, the principles of off‐loading and optimal wound care, the vast majority of diabetic foot ulcers can be expected to heal within 12 weeks of treatment. Education of primary care providers and patients is paramount.(WOUND REP REG 1999;7:7–16)
Incubation of cultured skin substitutes in reduced humidity promotes cornification in vitro and stable engraftment in athymic mice
Authors: Supp Andrew P. , Wickett R. Randall , Swope Viki B. , Harriger M. Dana , Hoath Steven B. , Boyce Steven T.
Published: March 2003

Cultured skin substitutes have been used successfully for adjunctive treatment of excised burns and chronic skin wounds. However, limitations inherent to all models of cultured skin include deficient barrier function in vitro, and delayed keratinization after grafting in comparison to native skin autografts. Experimental conditions for incubation of skin substitutes were tested to stimulate barrier development before grafting, and measure responses in function and stability after grafting. Cultured skin substitutes consisted of human keratinocytes and fibroblasts attached to collagen‐glycosaminoglycan biopolymer substrates. Parallel cultured skin substitutes were incubated at the air–liquid interface in ambient (48–61%) or saturated (79–91%) relative humidity, and grafted to athymic mice on culture day 14. Additional cultured skin substitutes were incubated in the experimental conditions for a total of 28 days. Cadaveric human skin and acellular biopolymer substrates served as controls. Epidermal barrier was evaluated as the change in surface hydration by surface electrical capacitance with the NOVA™ Dermal Phase Meter. Cultured skin substitutes and cadaveric skin incubated in ambient humidity had lower baseline surface electrical capacitance and less change in surface electrical capacitance than parallel samples incubated in saturated humidity at all time points in vitro. Data from healing cultured skin substitutes at 2, 4, 8 and 12 weeks after grafting showed an earlier return to hydration levels comparable to native human skin, and more stable engraftment for skin substitutes from ambient humidity. The data indicate that cultured skin substitutes in ambient humidity have lower surface electrical capacitance and greater stability in vitro, and that they reform epidermal barrier more rapidly after grafting than cultured skin substitutes in saturated humidity. These results suggest that restoration of functional epidermis by cultured skin substitutes is stimulated by incubation in reduced humidity in vitro.
Stimulation of wound healing by positively charged dextran beads depends upon clustering of beads and cells in close proximity to the wound
Authors: Tawil Nabil J , Connors David , Gies David , Bennett Steven , Gruskin Elliott , Mustoe Thomas
Published: March 2003

We have previously shown that positively charged dextran (DEAE A25) increases wound breaking strength in linear incisions in rats and nonhuman primates at days 10–14 postwounding. In this article, we examined the cellular responses to different types of charged dextran beads (DEAE A50 and Cytodex‐1) in culture studies and in rat incisional wounds. We show that Cytodex 1 and DEAE A50 beads also increased wound breaking strength in a rat linear incisional model. However, the increase was approximately 30–40% less than that observed in wounds treated with DEAE A25 beads. The main distinction between the three types of beads was the presence of bead clusters observed in tissue sections. Wounds treated with DEAE A25 beads formed distinct clusters while both Cytodex 1 and DEAE A50 beads clustered to a lesser extent or failed to cluster at all. We propose that the different types of charged dextran beads improve healing by promoting cell adhesion and encouraging proliferation in close proximity to the wound. We also hypothesize that the 30–40% improvement in wound breaking strength seen with DEAE A25 beads compared to other types of charged dextran beads (DEAE A50 and Cytodex‐1) originates from the unique characteristic of DEAE A25 beads in forming cell‐bead aggregates adjacent to the wounded area. This clustering, in turn, affects the distribution of cells infiltrating the wounded area (such as macrophages) during the healing process and, as a consequence, alters the distribution of matrix molecules and growth factors secreted by these cells.
Adenoviral‐mediated gene transfer in wound healing
Authors: Crombleholme Timothy M
Published: March 2003

The application of gene transfer strategies to wound healing is not an obvious use of this technology until one considers the important role of cytokines and growth factors in the normal wound healing response. Several gene transfer strategies have been proposed, from in vitro retroviral‐mediated gene transfer with autologous transplantation, to in vivo plasmid based gene transfer as retroviral gene transfer. The limitations of these approaches have been efficiency of gene transfer, transgene expression and biologic response. Adenoviral‐mediated gene transfer in wound healing is a relatively new application of this vector. The advantage of the adenovirus as a gene transfer vector lies in its ability to transduce nondividing cells of all types at very high efficiency without integration into the host cell's genome. The disadvantage of adenovirus as a vector is the relatively short duration of transgene expression and the inflammatory response it elicits. In the setting of wound healing brief duration of high levels of transgene may be all that is necessary to favorably influence wound healing. Secondly, as wound healing is fundamentally an inflammatory response, the inflammation elicited by the adenovirus may not be detrimental as long as the transgene is a growth factor with significant vulnerary effects such as platelet‐derived growth factor‐B. This review summarizes the current state of adenoviral‐mediated gene transfer in experimental models of impaired wound healing which have laid the groundwork for proposed phase I clinical trials of adenoviral‐mediated gene transfer of platelet‐derived growth factor‐B in chronic venous leg ulcers and chronic nonhealing diabetic foot ulcers. Adenoviral‐mediated gene transfer is a useful tool in the study of the role of specific cytokines and growth factors in normal and impaired wound healing. Adenoviral‐mediated gene transfer may hold significant promise for clinical application as a means of efficient growth factor delivery in correcting impaired wound healing.
Transplantation of virally transduced cells into the dermis of immunocompetent and immunodeficient (SCID) mice to determine gene expression profile and differential donor cell survival
Authors: Radfar Ali J , Robbins Paul D , Huard Johnny , Rosas Fabio R , Dohar Joseph E , Hebda Patricia A
Published: March 2003

Cell therapy and bioengineering hold great promise as therapeutic approaches using cells and cell‐derived factors to treat various pathologic or trauma‐induced states. One possible application is the transplantation of cells into wounded tissue to help regulate tissue repair. Cells engineered for optimal wound healing may help to minimize scarring following surgery or to enhance the rate of healing of chronic wounds. The purpose of the current study was to determine the effect of a viral insert, the LacZ‐bearing, first generation adenovirus AdRGD, on the survival of dermally transplanted murine skin allogenic fibroblasts. The LacZ insert facilitated quantitation of both cell survival and gene expression and was used here to measure viable cell number. In addition to bearing the LacZ marker, the AdRGD vector is capable of carrying therapeutic gene inserts, so this study tested the feasibility of gene therapy for wound healing. Murine skeletal muscle PP6 (i.e., Pre‐Plate 6) myogenic stem cells served as an alternate donor cell type. Cells were labeled with the LacZ‐bearing AdRGD adenovirus vector and injected (50,000 cells/site) into the dorsal skin of adult normal, immunocompetent mice as well as in immunodeficient SCID mice. Skin biopsies were taken on days 0, 1, 2, 3, and 7 post‐transplant, and assayed for LacZ expression. Soon after transplant (day 1), cell numbers underwent a transient decrease, but by day 2 post‐transplant they were present in appreciable numbers. Between days 2–7 post‐transplant, both allogenic fibroblasts and PP6 myogenic stem cells maintained survivability in similar numbers. Further, survival of transplanted cell types was similar in both normal, immunocompetent as well as SCID mice during this time period. There were no signs of acute inflammation or rejection in any of the samples. This study shows that AdRGD‐transduced cells are not immunogenic in the mouse skin model and the cells show similar survival for the first 7 days post‐transplantation independent of the cell type or immunocompetence of the host.
Bone marrow stem cell and progenitor response to injury
Authors: SILVA KUMUDIKA De , GAMELLI RICHARD L. , SHANKAR RAVI
Published: March 2003

Hematopoietic stem cells represent a long term reservoir of cells to populate blood with multiple formed cells. These hematopoietic stem cells proliferate and mature into lymphoid, erythroid, and myeloid precursor cells, with the balance of these cell populations modulated by major thermal injury, with or without sepsis. Recent studies indicate that thermal injury shifts this balance to favor the monocyte/macrophage lineage at the expense of neutrophil production. The mechanisms for these changes are now being elucidated with the results of clinical importance, because understanding the dynamics of the different precursor pools could be used to identify patients at greater risk for systemic inflammatory sequelae following major thermal injury.
Long‐term remodeling of a bilayered living human skin equivalent (Apligraf®) grafted onto nude mice: immunolocalization of human cells and characterization of extracellular matrix
Authors: Guerret Sylviane , Govignon Emmanuel , Hartmann Daniel J. , Ronfard Vincent
Published: March 2003

Type I collagen is a clinically approved biomaterial largely used in tissue engineering. It acts as a regenerative template in which the implanted collagen is progressively degraded and replaced by new cell‐synthesized tissue. Apligraf®, a bioengineered living skin, is composed of a bovine collagen lattice containing living human fibroblasts overlaid with a fully differentiated epithelium made of human keratinocytes. To investigate its progressive remodeling, athymic mice were grafted and the cellular and the extracellular matrix components were studied from 0 to 365 days after grafting. Biopsies were analyzed using immunohistochemistry with species‐specific antibodies and electron microscopy techniques. We observed that this bioengineered tissue provided living and bioactive cells to the wound site up to 1 year after grafting. The graft was rapidly incorporated within the host tissue and the bovine collagen present in the graft was progressively replaced by human and mouse collagens. A normal healing process was observed, i.e., type III collagen appeared transiently with type I collagen, the major collagen isoform present at later stages. New molecules, such as elastin, were produced by the living human cells contained within the graft. This animal model combined with species‐specific immunohistochemistry tools is thus very useful for studying long‐term tissue remodeling of bioengineered living tissues. (WOUND REP REG 2003;11:35–45)
Transitional blueschist–epidote amphibolite facies metamorphism in the Frankenberg massif, Germany, and geotectonic implications
Authors: RÖtzler  , Carswell  , Gerstenberger  , Haase
Published: March 2003

Bimodal metavolcanic rocks, granitic gneisses and metasediments are associated in the Frankenberg massif, Germany. These rocks are faulted against underlying very low‐grade Palaeozoic sequences and adjacent metamorphic complexes of the Variscan basement. The granitic gneisses record an Rb–Sr whole‐rock isochron age of 461±20 Ma that is taken as at least a minimum protolith age. The bimodal meta‐igneous suites are interpreted to have formed during rifting of the Gondwana continental margin in the Cambro‐Ordovician. The various metamorphic units have all experienced a common P–T  history. The peak‐pressure stage is constrained to around 490–520 °C and 10–14 kbar (10–12 kbar being most realistic). The metamorphism proceeded along a clockwise P–T path towards conditions of around 580–610 °C and 7–8.5 kbar at the thermal peak followed by a final low‐pressure overprint which spanned amphibolite facies to prehnite–actinolite facies temperatures. Owing to a secondary Rb–Sr whole‐rock isochron age of 381±24 Ma, interpreted to date the retrograde stage, the whole metamorphic cycle in the Frankenberg massif is ascribed to the late Silurian–early Devonian high‐pressure event widely recorded in the European Variscides. The antiformal complexes bordering the Frankenberg massif underwent a well‐documented early Carboniferous metamorphism, suggesting that the Frankenberg massif constitutes a klippe which was overthrust towards the end of this second metamorphic cycle.
Proterozoic metamorphism and uplift history of the north‐central Laramie Mountains, Wyoming, USA
Authors: PATEL*  , FROST  , CHAMBERLAIN  , SNYDER†
Published: March 2003

The Laramie Mountains of south‐eastern Wyoming contain two metamorphic domains that are separated by the 1.76 Ga. Laramie Peak shear zone (LPSZ). South of the LPSZ lies the Palmer Canyon block, where apatite U–Pb ages are c. 1745 Ma and the rocks have undergone Proterozoic kyanite‐grade Barrovian metamorphism. In contrast, in the Laramie Peak block, north of the shear zone, the U–Pb apatite ages are 2.4–2.1 Ga, the granitic rocks are unmetamorphosed and supracrustal rocks record only low‐T amphibolite facies metamorphism that is Archean in age. Peak mineral assemblages in the Palmer Canyon block include (a) quartz–biotite–plagioclase–garnet–staurolite–kyanite in the pelitic schists; (b) quartz–biotite–plagioclase–low‐Ca amphiboles–kyanite in Mg–Al‐rich schists, and locally (c) hornblende–plagioclase–garnet in amphibolites. All rock types show abundant textural evidence of decompression and retrograde re‐equilibration. Notable among the texturally late minerals are cordierite and sapphirine, which occur in coronas around kyanite in Mg–Al‐rich schists. Thermobarometry from texturally early and late assemblages for samples from different areas within the Palmer Canyon block define decompression from >7 kbar to <3 kbar. The high‐pressure regional metamorphism is interpreted to be a response to thrusting associated with the Medicine Bow orogeny at c. 1.78–1.76 Ga. At this time, the north‐central Laramie Range was tectonically thickened by as much as 12 km. This crustal thickening extended for more than 60 km north of the Cheyenne belt in southern Wyoming. Late in the orogenic cycle, rocks of the Palmer Canyon block were uplifted and unroofed as the result of transpression along the Laramie Peak shear zone to produce the widespread decompression textures. The Proterozoic tectonic history of the central Laramie Range is similar to exhumation that accompanied late‐orogenic oblique convergence in many Phanerozoic orogenic belts.
Pathways and distances of fluid flow during low‐grade metamorphism: evidence from pyrite deposits of the Cameros Basin, Spain
Authors: Alonso‐Azcárate  , Rodas  , Bottrell  , Raiswell  , Velasco  , Mas
Published: March 2003

New geochemical and sulphur isotopic data are presented for a number of pyrite deposits from the Late Jurassic–Early Cretaceous Cameros Basin, Spain. The deposits were formed at, or close to, the peak of metamorphism and are always related to sandstone units in the mainly metapelite sequence. Iron remained immobile and conservative, pyrite iron being derived by sulphidation of chlorite in the host metapelites. Reduced sulphur, however, was supplied from two external sources: thermochemical reduction of sulphate and release of S during metamorphism of sedimentary sulphides. These sources provided isotopically heavy and light S, respectively, with variation in pyrite isotopic composition between different deposits resulting from differences in their relative importance at each site. During metamorphism, the sandstone units acted as aquifers, carrying the sulphidic pore waters to locations where permeability provided by syn‐depositional fractures on a scale of 0.5–5 m allowed its interaction with the metapelites. Transport distances for sulphide during metamorphism were of the order of hundreds of metres.
Quantitative temperature‐time information from retrograde diffusion zoning in garnet: constraints for the P–T–t history of the Central Black Forest, Germany
Authors: Weyer  , Jarick  , Mezger
Published: March 2003

Garnet from a kinzigite, a high‐grade gneiss from the central Black Forest (Germany), displays a prominent and regular retrograde diffusion zoning in Fe, Mn and particularly Mg. The Mg diffusion profiles are suitable to derive cooling rates using recent datasets for cation diffusion in garnet. This information, together with textural relationships, thermobarometry and thermochronology, is used to constrain the pressure–temperature–time history of the high‐grade gneisses. The garnet–biotite thermometer indicates peak metamorphic temperatures for the garnet cores of 730–810 °C. The temperatures for the outer rims are 600–650 °C. Garnet–Al2SiO5–plagioclase–quartz (GASP) barometry, garnet–rutile–Al2SiO5–ilmenite (GRAIL) and garnet–rutile–ilmenite–plagioclase–quartz (GRIPS) barometry yield pressures from 6–9 kbar. U–Pb ages of monazite of 341±2 Ma date the low‐P high‐T metamorphism in the central Black Forest. A Rb/Sr biotite–whole rock pair defines a cooling age of 321±2 Ma. The two mineral ages yield a cooling rate of about 15±2 °C Ma−1. The petrologic cooling rates, with particular consideration of the fO2 conditions for modelling retrograde diffusion profiles, agree with the geochronological cooling rate. The oldest sediments overlying the crystalline basement indicate a minimum cooling rate of 10 °C Ma−1.
Microstructural tectonometamorphic processes and the development of gneissic layering: a mechanism for metamorphic segregation
Authors: Williams  , Melis  , Kopf  , Hanmer
Published: March 2003

The Mary granite, in the East Athabasca mylonite triangle, northern Saskatchewan, provides an example and a model for the development of non‐migmatitic gneissic texture. Gneissic compositional layering developed through the simultaneous evolution of three microdomains corresponding to original plagioclase, orthopyroxene and matrix in the igneous rocks. Plagioclase phenocrysts were progressively deformed and recrystallized, first into core and mantle structures, and ultimately into plagioclase‐rich layers or ribbons. Garnet preferentially developed in the outer portions of recrystallized mantles, and, with further deformation, produced garnet‐rich sub‐layers within the plagioclase‐rich gneissic domains. Orthopyroxene was replaced by clinopyroxene and garnet (and hornblende if sufficient water was present), which were, in turn, drawn into layers with new garnet growth along the boundaries. The igneous matrix evolved through a number of transient fabric stages involving S‐C fabrics, S‐C‐C′ fabrics, and ultramylonitic domains. In addition, quartz veins were emplaced and subsequently deformed into quartz‐rich gneissic layers. Moderate to highly strained samples display extreme mineralogical (compositional) segregation, yet most domains can be directly related to the original igneous precursors. The Mary granite was emplaced at approximately 900 °C and 1.0 GPa and was metamorphosed at approximately 750 °C and 1.0 GPa. The igneous rocks crystallized in the medium‐pressure granulite field (Opx–Pl) but were metamorphosed on cooling into the high‐pressure (Grt–Cpx–Pl) granulite field. The compositional segregation resulted from a dynamic, mutually reinforcing interaction between deformation, metamorphic and igneous processes in the deep crust. The production of gneissic texture by processes such as these may be the inevitable result of isobaric cooling of igneous rocks within a tectonically active deep crust.
Cretaceous high‐P granulites at Milford Sound, New Zealand: metamorphic history and emplacement in a convergent margin setting
Authors: Clarke G. L. , Klepeis K. A. , Daczko N. R.
Published: March 2003

Granulite facies orthogneiss of the Arthur River Complex (ARC) at Milford Sound, western Fiordland records a complex Early Cretaceous magmatic and orogenic history for the Pacific Gondwana margin that culminated in the emplacement and burial of a dioritic batholith, the Western Fiordland Orthogneiss (WFO). Enstatite‐bearing mafic to intermediate protoliths of the ARC and WFO intruded the middle to upper crust. The early deformation history of the ARC is preserved in the Pembroke Granulite, where two‐pyroxene S1 assemblages that reflect P<8 kbar and T >750 °C were only patchily recrystallized during later deformation. S1 is cut by garnet‐bearing, leucogabbroic to dioritic veins, which are cut by distinctive D2 fractures involving anorthositic veins and garnet–diopside–plagioclase‐bearing reaction zones. These zones are widespread in the ARC and WFO and record conditions of P≈14 kbar and T >750 °C. Garnet–clinopyroxene‐bearing corona reaction textures that mantle enstatite in both the ARC and WFO reflect Early Cretaceous burial by approximately 25 km of continental crust. Most of the ARC is formed from the Milford and Harrison Gneisses, which contain steeply dipping S4 assemblages that envelop the Pembroke Granulite and involve garnet, hornblende, diopside, clinozoisite, rutile and plagioclase, with or without kyanite. The P–T history of rocks in western Fiordland reflects pronounced Early Cretaceous convergence‐related tectonism and burial, possibly related to the collision and accretion of island arc material onto the Pacific Gondwana margin.
Geochronological constraints on the timing of granitoid magmatism, metamorphism and post‐metamorphic cooling in the Hercynian crustal cross‐section of Calabria
Authors: Graessner T. , Schenk V. , Bröcker M. , Mezger K.
Published: March 2003

Exposed cross‐sections of the continental crust are a unique geological situation for crustal evolution studies, providing the possibility of deciphering the time relationships between magmatic and metamorphic events at all levels of the crust. In the cross‐section of southern and northern Calabria, U–Pb, Rb–Sr and K–Ar mineral ages of granulite facies metapelitic migmatites, peraluminous granites and amphibolite facies upper crustal gneisses provide constraints on the late‐Hercynian peak metamorphism and granitoid magmatism as well as on the post‐metamorphic cooling. Monazite from upper crustal amphibolite facies paragneisses from southern Calabria yields similar U–Pb ages (295–293±4 Ma) to those of granulite facies metamorphism in the lower crust and of intrusions of calcalkaline and metaluminous granitoids in the middle crust (300±10 Ma). Monazite and xenotime from peraluminous granites in the middle to upper crust of the same crustal section provide slightly older intrusion ages of 303–302±0.6 Ma. Zircon from a mafic to intermediate sill in the lower crust yields a lower concordia intercept age of 290±2 Ma, which may be interpreted as the minimum age for metamorphism or intrusion. U–Pb monazite ages from granulite facies migmatites and peraluminous granites of the lower and middle crust from northern Calabria (Sila) also point to a near‐synchronism of peak metamorphism and intrusion at 304–300±0.4 Ma. At the end of the granulite facies metamorphism, the lower crustal rocks were uplifted into mid‐crustal levels (10–15 km) followed by nearly isobaric slow cooling (c. 3 °C Ma−1) as indicated by muscovite and biotite K–Ar and Rb–Sr data between 210±4 and 123±1 Ma. The thermal history is therefore similar to that of the lower crust of southern Calabria. In combination with previous petrological studies addressing metamorphic textures and P–T  conditions of rocks from all crustal levels, the new geochronological results are used to suggest that the thermal evolution and heat distribution in the Calabrian crust were mainly controlled by advective heat input through magmatic intrusions into all crustal levels during the late‐Hercynian orogeny.
Microstructural constraints on the timing of Proterozoic deformation in Central New Mexico
Authors: Ralser
Published: March 2003

The nature and extent of deformation associated with 1.4 Ga tectonism in the south‐western USA are poorly understood. Two models have been proposed. Both agree that Proterozoic crustal accretion occurred at 1.65 Ga and that the rocks remained at mid‐crustal conditions (c. 12 km depth) until 1.4 Ga. However, one model suggests that 1.4 Ga deformation was regionally extensive, the other that it was localized around 1.4 Ga plutons. Following 1.4 Ga tectonism, the crust cooled below 300 °C. Detailed studies of quartz mylonite microfabrics in samples both adjacent to and removed from 1.4 Ga plutons in the Manzano Mountains, central New Mexico, are used to discriminate between these models of mid‐Proterozoic thermotectonic history. In this area, as in much of northern New Mexico, the metamorphic conditions prior to emplacement of 1.4 Ga plutons were 500 °C and 4 kbar. The quartz mylonite microfabrics include ribbon grains, recrystallized grains with serrated boundaries, and strong c‐axis crystallographic preferred orientations, which indicate no post‐deformational modification. All of these microfabrics are consistent with deformation at upper greenschist/lower amphibolite facies conditions, and could have formed during either 1.65 or 1.4 Ga tectonism. Microfabrics formed during 1.65 Ga tectonism, however, should have been substantially modified by annealing recrystallization during residency in the middle crust and/or thermal/mechanical effects associated with 1.4 Ga tectonism. The observed microstructures are consistent with regional deformation associated with metamorphism at 1.4 Ga. The effects of deformation at 1.4 Ga in New Mexico are therefore more widespread than previously thought.