bluuebunny/crossref_metadata_2025 huggingface dataset:
Eleven new microsatellites for hop (Humulus lupulus L.)
Authors: Jakše J. , Bandelj D. , Javornik B.
Published: March 2003

We present a new set of 11 polymorphic microsatellite primer sequences for use with Humulus lupulus. Microsatellite‐enriched libraries for GAn and GTn types of repeats were produced. Sequencing of 72 clones revealed 42 unique inserts containing microsatellites, out of which 19 primer pairs were designed and microsatellite amplification was tested on 39 wild hops and cultivars. Eleven primer pairs showed single locus amplification with 2–13 alleles, average 7.2, of which 17 unique alleles were discovered. One primer pair amplified too strong stutter bands, one locus was monomorphic and multilocus amplification was obtained with the remaining six primer pairs.
Changes in self‐esteem during a 3 year pre‐registration diploma in higher education (nursing) programme
Authors: Randle Jacqueline
Published: March 2003

This paper reports the findings of a longitudinal study that evaluated changes in the self‐esteem of pre‐registration student nurses taking a 3 year diploma in nursing programme. Quantitative data were collected at the start (n = 68) and the end (n = 61) of the programme. Self‐esteem was measured using the Tennessee Self‐concept Scale (Roid & Fitts 1988). Students also participated in unstructured, qualitative interviews at the start (n = 56) and end (n = 39) of the course. Results showed that global self‐esteem decreased dramatically between the start and end of the programme. Categories grounded in the qualitative data suggest that self‐esteem becomes fragmented and students become powerless to be the type of nurse they wish to be. The implications for nursing practice and education are discussed.
Trends in annual and seasonal survival of Pink‐footed GeeseAnser brachyrhynchus
Authors: Madsen Jesper , Frederiksen Morten , Ganter Barbara
Published: March 2003

Adult Pink‐footed GeeseAnser brachyrhynchusfrom the Svalbard breeding population were neck‐banded and resighted in staging and wintering areas outside the breeding season 1990–1999. We estimated annual and seasonal survival using capture–recapture statistical models. Mean annual survival was 0.829, declining over the study period from 0.90 to 0.79. The annual cycle was partitioned into three periods: summer (1 April–30 September), including both spring and autumn migration, autumn (1 October–31 December), including most shooting, and winter (1 January–31 March). The parsimonious model selected to describe seasonal survival included a declining trend in summer survival, constant autumn and winter survival with lower survival in the severe winter of 1996, and an additive effect of sex on summer and winter survival. Monthly survival was highest during winter. Decreasing summer survival was the main contributor to the overall decline in annual survival, and was attributed mainly to increasing natural mortality on the breeding grounds. Mean annual survival based on the seasonal survival probabilities was 0.835 for females and 0.805 for males. The effect of sex was most pronounced during summer and remains to be explained.
Reproductive performance of Common Goldeneye Bucephala clangula females in relation to age and lifespan
Authors: Milonoff Markku , Pöysä Hannu , Runko Pentti
Published: March 2003

We studied the effects of female age and length of lifespan on reproductive performance in the Common Goldeneye Bucephala clangula, a precocial species with self‐feeding chicks. Dependent variables studied were the occurrence of failed nesting attempts and non‐breeding years, clutch size, nesting and hatching success, female condition and recovery rate of offspring. To avoid misinterpretations resulting from age‐dependent quality changes in the cohorts, individuals with different lifespans were separated in the analyses. There was no evidence that females of different lifespan differed in reproductive strategy. The data revealed no significant differences in nest losses, occurrence of non‐breeding years, timing of nesting or clutch size, but the physiological condition of short‐lived females was poorer than that of longer living females. This accords with the prediction that poor‐quality females invest proportionally more in reproduction than high‐quality females and consequently die earlier. The most productive individuals were those that lived longest. The only indication of senescence was the low recovery rate of offspring produced by old females. The last breeding attempt did not differ in any observable respect from the penultimate attempt, implying that the last investment in reproduction was no heavier than the previous one.
Does supplementary calcium reduce the cost of reproduction in the Pied Flycatcher Ficedula hypoleuca?
Authors: Mänd Raivo , Tilgar Vallo
Published: March 2003

Studies in acidified as well as in naturally base‐poor areas have recently revealed that availability of extra calcium‐rich food items is an important component of habitat quality affecting breeding performance in several bird species. However, these mostly short‐term studies have provided equivocal results concerning the exact consequences of calcium shortage on different species in different regions. We studied the effect of calcium availability on reproduction of the Pied Flycatcher Ficedula hypoleuca breeding in pine forests in Estonia, NE Europe, over a period of 4 years. Experimental pairs were provided with supplementary calcium‐rich material when breeding, while control pairs were left unsupplemented. Experimental females laid larger eggs and their nestlings had longer tarsi than those of controls. Moreover, the mass and condition of females tending larger than average clutches were increased by calcium‐supplementation. Our results provide the first experimental evidence that calcium availability may affect the overall cost of reproduction in free‐living passerines. We compared these results with similar data for the Great Tit Parus major, collected from the same area during the same study period. Great Tits responded to low calcium availability mainly by restrained reproductive behaviour and reduced breeding success, while Pied Flycatchers invested significantly more in current reproductive effort despite the increased cost of reproduction. Thus, the effects of calcium deficiency on birds seem to be species‐specific or population‐specific. This partly explains discrepancies between the results of earlier studies.
Why birds sing at dawn: the role of consistent song transmission
Authors: Brown Timothy J. , Handford Paul
Published: March 2003

The dawn chorus is a widely observed phenomenon. One of the common, but inadequately studied, explanations for the occurrence of the dawn chorus is based on the rationale that atmospheric turbulence, which impairs acoustic communication, is least at dawn, and thus singing at dawn in some way maximizes signal performance. To investigate what possible acoustic benefit is gained through singing at dawn, we transmitted Swamp Sparrow Melospiza georgiana and White‐throated Sparrow Zonotrichia albicollis song through open grassland and closed forest both at dawn and at midday. The transmitted songs were re‐recorded at four distances from 25 to 100 m. Our results show that the mean overall absolute transmission quality of the signals was not significantly better at dawn than at midday. However, the signal transmission quality was significantly more consistent at dawn than at midday. Also, in general, signal transmission quality decreased with increasing distance. Variability in the transmission quality increased with distance for the White‐throated Sparrow song, but not for the Swamp Sparrow song. Consistency in signal transmission quality is a factor that, arguably, is crucial for the identity function of song. This study strongly supports the acoustic transmission hypothesis as an explanation for the existence of the dawn chorus while the demonstration of variability as a key factor in singing at dawn is novel.
Repeatability of subjective refraction in myopic and keratoconic subjects: results of vector analysis
Authors: Raasch Thomas W. , Schechtman Kenneth B. , Davis Larry J. , Zadnik Karla ,   The CLEK Study Group
Published: March 2003

This paper evaluates the repeatability of refraction in keratoconus patients and normal myopes, using representations of spherocylindrical power that are theoretically valid. Data consist of test–retest refraction data from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study and similar data from normal myopes. Dioptric powers are transformed to an orthogonal vector representation of dioptric power. The metric of change is the dioptric difference between test and retest. The median difference between test and retest in keratoconus patients is four to six times larger than in normal myopes. Refraction over a rigid contact lens on a keratoconic cornea improves repeatability but remains approximately twice as large as in normal myopes. The methods demonstrated here possess advantages over previous methods and provide a more valid comparison between test and retest and between different subject groups. The repeatability of refraction in keratoconus patients is substantially worse than in normal myopes.
Referral rates for a functional vision screening among a large cosmopolitan sample of Australian children
Authors: Junghans Barbara , Kiely Patricia M. , Crewther David P. , Crewther Sheila Gillard
Published: March 2003

The aim of this study was to investigate the incidence of functional vision problems in a large unselected cosmopolitan population of primary school‐age children and to investigate whether constant clinical criteria for functional vision problems would be implemented by the practitioners involved in the screening. Refractive errors, near point of convergence, stereopsis, strabismus, heterophoria and accommodative facility were assessed for 2697 children (3–12 years) of varying racial backgrounds living in Australia. The spherical component of the refractive error ranged from −7.75 to +9.50 D (mean +0.54 D, ±0.79) with a distribution skewed towards hypermetropia; astigmatism ranged from 0 to 4.25 D (mean −0.16 D, ±0.35). There was a trend towards less hypermetropia and slightly more astigmatism with age. Mean near point of convergence was 5.4 ± 2.9 cm, heterophoria at far and near was 0.12 ± 1.58Δ exophoria and 1.05 ± 2.53Δ exophoria, respectively, 0.55% of children exhibited vertical phoria at near >0.5Δ, accommodative facility ranged from 0 to 24 cycles per minute (cpm) (mean 11.2 cpm, ±3.7), stereopsis varied from 20 to 800 s (′′) of arc with 50% of children having 40′′ or better. The prevalence of strabismus was particularly low (0.3%).

Twenty percent of the children were referred for further assessment based on criteria of one or more of: stereopsis >70′′, accommodative facility <8 cpm, near point of convergence (NPC) >9 cm, near exophoria >10Δ or near esophoria >5Δ, shift in eso or exophoria ≥ 4Δ between distance and near, astigmatism ≥ 1 D, myopia more than −0.75 D, or hyperopia >+1.50 D. Post‐hoc analysis of the record cards seeking the reason for further assessment indicates that referrals appear to have been based upon clinical intuition rather than on a set number of borderline or unsatisfactory results.
A multi‐centre study of lapsed contact lens wearers
Authors: Young Graeme , Veys Jane , Pritchard Nicola , Coleman Sarah
Published: March 2003

Purpose:  Discontinuation from contact lens wear has been identified as a contributing factor in the lack of growth of contact lens use in Europe. The purpose of this study was to determine the proportion of lapsed contact lens wearers that can be refitted successfully with contact lenses and to evaluate the reasons for discontinuation from contact lens wear.

Methods:  This was a multi‐site clinical study involving 15 UK investigators and 236 lapsed contact lens wearers who had previously tried contact lenses and discontinued. The reasons for discontinuation were assessed by subjects, who were then refitted with contact lenses. Investigators subsequently evaluated factors associated with their initial discontinuation. Short‐term success was defined as the successful completion of 1 month of contact lens wear with absence of complications that would prevent further wear. Subjects were interviewed by telephone 6 months after being refitted to determine whether they were still wearing contact lenses. Those who were not wearing lenses were questioned about the reasons for discontinuation and their likelihood of resuming lens wear.

Results:  A majority of subjects (51%) cited discomfort as the principal reason for having previously given up contact lens wear. Problems with vision were the second most common reason (13%), either with reading (6%) or general vision (7%). The most common type of discomfort was dryness (40%). In almost all cases (97%), the investigator's assessment of the reasons for discontinuation agreed with the subject's own assessment but investigators also cited product‐related and practitioner‐related factors as contributing to previous failure. The short‐term success rate for refitting lapsed wearers was found to be 77% (CI: 70–82%). The highest short‐term success rates were for 2‐weekly/monthly soft spherical lenses (91%) and daily disposable lenses (89%). Lower success rates were found for soft toric (69%) and soft bifocal (53%) lenses. At the 6‐month stage, 73% of those who continued in lenses after the 1‐month visit were still wearing contact lenses and a further 18% indicated that they were either ‘very likely’ or ‘likely’ to resume lens wear.

Conclusions:  A high proportion of lapsed contact lens wearers can be successfully refitted with contact lenses. The prime reason for previous discontinuation from contact lenses is discomfort and, in particular, dryness‐related discomfort. In many cases, previous contact lens failure is product or practitioner‐related rather than because of patient‐specific problems. Once refitted with contact lenses, lapsed wearers cite vision problems rather than discomfort as the most common reason for discontinuing. This finding suggests that recent advances in contact lens material, design, replacement frequencies and care systems have improved the prospects for avoiding lens‐related discomfort and for continuing contact lens wear.
Efficacy of treatment for convergence insufficiency using vision therapy
Authors: Adler Paul
Published: March 2003

Purpose: The purpose of this study was to determine if vision therapy (VT), as practised within the constraints of UK optometric practice, employing graded routine eye exercises, is as an effective method for treatment of convergence insufficiency (CI) as previously published data suggest. The study also evaluates the associated symptoms before and after therapy.

Methods: As many optometrists diagnose CI solely on the basis of near point of convergence (NPC) and treat only when symptoms are present (Letourneau et al., 1979; Rouse et al., 1997), in this study CI was defined as NPC of 10 cm or greater (either with or without the presence of asthenopic symptoms for near work) accompanied by exophoria greater at near than at distance. The effect of treatment by optometric vision therapy (OVT) on the NPC and number of symptoms was investigated for 92 patients by retrospectively reviewing the clinical records. Success was defined as the restoration of NPC to normal values and significant reduction in the presenting symptoms.

Results: The effect of treatment on the NPC was shown to be highly significant (t = 14.61, p < 0.001). Although treatment times were slightly longer, the success rates were higher than reported by other authors. Post‐treatment values for NPC were: <10 cm (98.9%), <8.5 cm (95.7%) and <6.5 cm (80.4%). Longer treatment times were noted for patients who complained that the text appeared to move (χ2, p = 0.007).

Conclusion: Vision therapy is an effective method for treatment of CI.
Stereoacuity versus fixation disparity as indicators for vergence accuracy under prismatic stress
Authors: Kromeier Miriam , Schmitt Christina , Bach Michael , Kommerell Guntram
Published: March 2003

Background: Fixation disparity has been widely used as an indicator for vergence accuracy under prismatic stress. However, the targets used for measuring fixation disparity contain artificial features in that the fusional contours are thinned out. We considered that stereoacuity might be a preferable indicator of vergence accuracy, as stereo targets represent natural viewing conditions.

Methods: We measured fixation disparity with a computer adaptation of Ogle's test and stereoacuity with the automatic Freiburg Stereoacuity Test. Eight subjects were examined under increasing base‐in and base‐out prisms.

Results: The response of fixation disparity to prismatic stress revealed the curve types described by Ogle and Crone. All eight subjects reached a stereoscopic threshold below 10 arcsec. In seven subjects the stereoscopic threshold increased before double vision occurred.

Conclusion: Our data suggest that stereoacuity is suitable to assess the range of binocular vision under prismatic stress. As stereoacuity bears the advantage over fixation disparity in that it can be measured without introducing artificial viewing conditions, we suggest exploring whether stereoacuity under prismatic stress would be more meaningful in the work‐up of asthenopic patients than is fixation disparity.
Avoidance and Management of Complications of Total Parenteral Nutrition
Authors: Khaodhiar Lalita , Bistrian Bruce R.
Published: March 2003

Abstract Total parenteral nutrition therapy can be life‐saving for specific groups of patients, but is not without risks. Complications that may occur are divided into three groups: mechanical, infectious, and metabolic. While mechanical complications related to central venous catheter placement can be minimized by the skill and experience of the operator, infectious and metabolic complications, such as hyperglycemia and electrolyte abnormalities, are more likely to be decreased by careful observation and monitoring of the patient. Certain guidelines, which are presented here, should be followed to prevent such complications, while problems that may occur should be recognized and treated promptly.
Important Relationships Between Diet, Nutrition, and Oral Health
Authors: Palmer Carole A.
Published: March 2003

Nutritional factors are important for dental health. Diet and nutritional status contribute to the development of caries, periodontal disease, osteoporosis, and other conditions. Primary care clinicians can play an important role in the maintenance of oral health; likewise, dentists should not neglect nutritional issues. This review describes the role of various nutritional factors on oral health; special concerns for pregnant women, infants, toddlers, children, adolescents, adults, and elders; and specific oral health concerns of individuals with various medical conditions.
The Continuity of Nutrition Care Through Liver Transplantation
Authors: Vintro Andrea Q.
Published: March 2003

Recent advancements in pharmacotherapies and medical technologies have significantly improved long‐term survival rates after liver transplantation. However, as survival rates increase, so do incidences of other chronic diseases more commonly associated with advanced age. In fact, as a population, post‐liver‐transplant patients are at greater risk for cardiovascular disease, diabetes mellitus, cancer, and osteoporosis than the general public. Moreover, disease risk factors such as hyperglycemia, dyslipidemia, hypertension, and excess weight gain continue to plague this population despite reduced‐dose requirements for immunosuppressives—a class of drugs with numerous side effects—which, historically, were thought to contribute heavily to chronic disease risk. Thus, clinicians treating liver‐transplant candidates are challenged to broaden the scope of their care to include prevention of other chronic diseases that may have strong nutritional components. Although nutrition and medical therapies should continue to treat specific symptoms associated with the stages of liver disease and transplantation, therapies and information provided to pre‐transplant patients should include preventative measures to ensure optimal outcomes for improved longevityaftertransplant. The medical team should utilize the nutritional expertise of dietitians to lead this continuity of care through all stages of liver transplantation. To maximize longevity and quality of life, dietary intervention for chronic disease prevention should be implemented as soon as medically feasible. This paper reviews nutrition therapies for complications seen during liver transplantation and proposes individualized diet recommendations to be considered at the very earliest stages of caring for patients with liver disease.
Nutritional Factors in the Control of Blood Pressure and Hypertension
Authors: Suter Paolo M. , Sierro Christophe , Vetter Wilhelm
Published: March 2003

Differing hypertension prevalence rates between certain population and age groups are partially due to differences in the intake of certain nutrients. Blood pressure is positively associated with higher sodium, alcohol, and protein intakes; it is inversely associated with potassium, calcium, and magnesium intakes. Salt may lead to an increase in blood pressure in the presence of salt sensitivity, but there is no inexpensive or easy strategy to identify salt‐sensitive patients. Other risk factors for hypertension include obesity and lack of regular physical activity.

The best strategy appears to be moderate salt restriction (6–7 g/day) in combination with an optimal compliance of the antihypertensive drug therapy, as well as adoption of the combination diet of the DASH study—a diet rich in fruits and vegetables, and thus rich in potassium. Current evidence does not support the increased intake of Ca2+ or Mg2+ for blood‐pressure‐lowering purposes only; however, calcium and magnesium may represent important components in the combination diet of the DASH study. It seems that it is the combination of these nutrients that is of crucial importance for the achievement of optimal blood‐pressure reduction. Also recommended is a decrease in alcohol consumption and an increase in regular physical activity. Instead of a severe intervention with regard to 1 risk factor alone, positive changes in 5 habits combined—high salt intake, high sodium‐to‐potassium ratio, alcohol intake, calorie imbalance, and a sedentary life—may be the most realistic and effective strategy to counteract the present hypertension epidemic.
Impaired proliferation and increased L‐lactate production of dermal fibroblasts in the GK‐rat, a spontaneous model of non‐insulin dependent diabetes mellitus
Authors: Hehenberger Karin , Hansson Anders , Heilborn Johan D. , Abdel‐Halim Samy M. , Östensson Claes‐Göran , Brismar Kerstin
Published: March 2003

Intact fibroblast function is required for normal wound healing. Although healing is generally accepted to be disturbed in non‐insulin dependent diabetes mellitus, the signals modulating this disturbance are not fully understood. Therefore, we studied dermal fibroblasts from the GK rat, a non‐insulin dependent diabetes mellitus model, and the Wistar rat (control) regarding growth characteristics, and L‐lactate production at 5.5 mM and 25.5 mM glucose in the absence or presence of protein kinase C‐inhibition, or α‐tocopherol acetate. In addition, growth and L‐lactate responses to hyaluronic acid were assessed under normal glucose conditions. At 5.5 mM glucose, the fibroblasts from the GK rat showed a lower proliferation rate during the first 24 hours, measured as DNA content, as compared to Wistar rats, i.e. at 8 hours GK was 57% of control, p < 0.01, at 24 hours GK was 60% of control, p < 0.01. The GK rat fibroblasts accumulated higher L‐lactate levels in the media at 24–96 hours. Addition of glucose at a concentration of 25.5 mM decreased the total DNA content in GK rat fibroblast cultures to 74% (p < 0.05) and in control to 87% (p < 0.05), and increased L‐lactate levels, measured at 48 hours. A protein kinase C‐inhibitor, bisindolylmaleimide IX, increased DNA content and decreased L‐lactate in both cell types during culture in high glucose, but only affected GK rat fibroblasts during normal glucose. Hyaluronic acid, increased DNA content in both types of fibroblasts, GK: 139% (p < 0.05), control: 127% (p < 0.05) and reduced L‐lactate production. The above observations indicate that GK rat fibroblast proliferation is suppressed when the cells are cultured in high glucose containing media. In addition, protein kinase C and hyaluronic acid might play a role as modulators of fibroblast proliferation during the diabetic state. (WOUND REP REG 1999;7:65–71)
Recombinant adenoviral mediated gene transfer in ischemic impaired wound healing
Authors: Liechty Kenneth W , Sablich Timothy J , Adzick N. Scott , Crombleholme Timothy M
Published: March 2003

Chronic nonhealing wounds represent a large clinical problem resulting in severe disabilities and large healthcare expenditures. Despite the scope of this problem, effective new therapies are lacking. The deficiency of growth factors in chronic wounds has brought attention to the topical application of growth factors, but initial clinical trials have resulted in only modest improvements in healing despite large, repetitive doses. The modest improvement in healing observed in these trials show that growth factors can improve chronic wound healing, but a better means of growth factor delivery is needed. We hypothesized that gene therapy using a recombinant adenoviral vector could be used to induce transgene production directly by cells in the wound. An adenovirus containing the β‐galactosidase reporter transgene (Ad‐LacZ) was used in the ischemic rabbit ear model to test this hypothesis. Ad‐LacZ resulted in efficient transgene delivery to cells participating in the wound healing response, with expression up to 2 weeks. However, wound reepithelialization was impaired in Ad‐LacZ treated wounds compared to vehicle control wounds. Adenoviral mediated gene transfer is a promising efficient means of growth factor delivery to chronic wounds. However, selection of the proper transgene with appropriate biologic activity in wound healing may be essential to overcome the potential adverse effects of adenoviral infection.
Matrix metalloproteinases in repair
Authors: Parks William C.
Published: March 2003

During repair, many different matrix metalloproteinases are produced by multiple cell types residing in various compartments within the wound environment. This diversity of enzymes, coupled with discreet cellular expression, implies that different matrix metalloproteinases serve different functions, acting on a variety of substrates, during wound healing. With few exceptions, however, the actual function and spectrum of functions of matrix metalloproteinases in vivo is not known. Even with the advent of genetically defined animal models, few studies have rigorously addressed the substrates and role of matrix metalloproteinases in wound repair. Before we can understand the role of matrix metalloproteinases in ulceration and disease, we need to determine the function these enzymes serve in normal tissues and repair.
Mechanical loading regulates protease production by fibroblasts in three‐dimensional collagen substrates
Authors: Prajapati Rita T , Chavally‐Mis Beatrice , Herbage Daniel , Eastwood Mark , Brown Robert A
Published: March 2003

Mechanical loading is important in tissue formation and remodelling, notably in wound repair. The aim of this study was to measure the effects of controlled loading on the release of extracellular matrix protease activities by fibroblasts. Fibroblast populated collagen lattices were subjected to external cyclical loads through a computer controlled unit incorporated into a culture system, a tensioning‐Culture Force Monitor. Cyclical loading was compared to untensioned and statically loaded gels (tethered endogenous contraction). Overall changes in a range of protease activities were monitored (chiefly by zymography) as measures of the cyto‐mechanical response to these loads. Under static load, 2.5‐ and 13‐fold more matrix metalloproteinase‐2 was produced than matrix metalloproteinase‐9, at 24 and 48 hours. Total matrix metalloproteinase‐9 increased 37 fold on cyclical loading. Total matrix metalloproteinase‐3 and urokinase plasminogen activator activities were dramatically reduced on cyclical loading while tissue type plasminogen activator activity was increased. Comparison with cell responses on stiffer substrates (collagen sponges) identified similar matrix metalloproteinase responses to load, but at much reduced levels (4–6 fold matrix metalloproteinase‐9 stimulation on loading), showing the importance of matrix compliance to this mechano‐response. In conclusion, physiological mechanical loading of fibroblasts in three dimensional collagen lattices elicited complex and substantial changes in matrix modifying proteases. These changes suggest that cells switch between expression of comparable protease activities mainly influencing cell–matrix interactions associated with migration or more generalized extracellular matrix remodelling.
Duration and orientation of mechanical loads determine fibroblast cyto‐mechanical activation: Monitored by protease release
Authors: Prajapati Rita T , Eastwood Mark , Brown Robert A
Published: March 2003

Regulation of mechanical force on and by connective tissues is increasingly regarded as a critical factor in understanding their function. The aim of this study was to identify quantifiable characteristics of external loading to which fibroblasts were sensitive. Specific patterns of uniaxial tensile loading were applied to fibroblast populated collagen lattices through a computer controlled driver: tensioning‐Culture Force Monitor. Ramp loads of 120 dynes were applied over 10 minutes and 11 hours, and the effect of high and low strain pattern changes, with orientation relative to the applied load were investigated by using two lattice configurations, high and low aspect ratios, with loads applied across the long and short axis. Both, ramp loading and lattice orientation were tested in comparison to statically loaded gels. Changes in protease production were measured to indicate which loading patterns produced cell stimulation. Greatest cell responses were with the slowest rate of ramp loading and unloading (11 dynes/hour) with the 11 hour ramp causing a 5‐fold increase in MMP‐9 release. Similarly, the greatest stimulation was produced in high strain, aligned High Aspect Ratio lattices with a 2.6‐fold increase in MMP‐9 release. In conclusion, duration over which cells are loaded rather than the rate and alignment of that loading are both critical factors in cyto‐mechanical activation.
Advances in wound healing research in China: From antiquity to the present
Authors: Fu Xiaobing , Wang Zhengguo , Sheng Zhiyong
Published: March 2003

China is the largest developing country in the world with wounds occuring everyday and everywhere, representing one of the main killers of people. Prevention and treatment of wounds are the main tasks for Chinese surgeons. Although wound care and management have a long history in China, wound healing research and management have made significant progress only in recent years. In this article we give a brief account of the history of wound care and management in China. In addition, we introduce the main research fields and achievements in tissue repair and regeneration during recent times in this country. We hope that these works will benefit our foreign colleagues to know our work and enhance the communication among us.
Cones of skin occur where hypertrophic scar occurs
Authors: Matsumura Hajime , Engrav Loren H. , Gibran Nicole S. , Yang Tai‐Mei , Grant John H. , Yunusov Murad Y. , Fang Peiyao , Reichenbach Dennis D. , Heimbach David M. , Isik F. Frank
Published: March 2003

Hypertrophic scarring is devastating for the patient, however the pathophysiology and treatment remain unknown after decades of research. The process follows deep dermal injury, occurs only on certain body parts, does not occur in the early fetus or in animals, and is a localized event. This suggests that an anatomic structure in human, deep dermis may be involved. The dermis is a matrix perforated by cones containing many structures including skin appendages and fat domes. We hypothesized that studying the cones might reveal a structure related to scarring. We examined tangential wounds from various body parts on human cadavers along with skin histology from various human body parts, the early fetus, partial thickness burns, hypertrophic scars, and two other species—rats and rabbits. We found that the cones may in fact be the structure. They exist where hypertrophic scar occurs—cheek, neck, chest, abdomen, back, buttock, arm, forearm, dorsal hand, thigh, leg, dorsal foot, helix and ear lobe. They do not exist where hypertrophic scar does not occur—scalp, forehead, concha, eyelid, palm, early fetus, and in rat, or rabbit. It also became apparent that the cones have been omitted from most considerations of skin histology. We suggest that the cones need to be studied in relation to hypertrophic scarring and restored to skin diagrams.
Neutral endopeptidase inhibition in diabetic wound repair
Authors: Spenny Michelle L. , Muangman Pornprom , Sullivan Stephen R. , Bunnett Nigel W. , Ansel John C. , Olerud John E. , Gibran Nicole S.
Published: March 2003

In response to cutaneous injury, sensory nerves release substance P, a proinflammatory neuropeptide. Substance P stimulates mitogenesis and migration of keratinocytes, fibroblasts, and endothelial cells. Neutral endopeptidase (NEP), a cell surface metallopeptidase, degrades substance P. Chronic nonhealing wounds and skin from patients with diabetes mellitus show increased NEP localization and activity. We hypothesized that increased NEP may retard wound healing and that NEP inhibition would improve closure kinetics in an excisional murine wound model. NEP enzyme activity was measured in skin samples from mutant diabetic mice (db/db) and nondiabetic (db/–) littermates by degradation of glutaryl‐ala‐ala‐phe‐4‐methoxy‐2‐naphthylamine. Full‐thickness 6‐mm dorsal excisional wounds treated with normal saline or the NEP inhibitor thiorphan (10 µM or 25 µM) for 7 days were followed until closure. Histological examination and NEP activity were evaluated in a subset of wounds. NEP activity in unwounded db/db skin (20.6 pmol MNA/hr/µg) significantly exceeded activity in db/–skin (7.9 pmol MNA/hr/µg; p = 0.02). In db/db mice, 25 µM thiorphan shortened time to closure (18.0 days; p < 0.05) compared to normal saline (23.5 days). NEP inhibition did not alter closure kinetics in db/–mice. While the inflammatory response appeared enhanced in early wounds treated with thiorphan, blinded histological scoring of healed wounds using a semiquantitative scale showed no difference in inflammation. Unwounded skin from diabetic mice shows increased NEP activity and NEP inhibition improved wound closure kinetics without affecting contraction, suggesting that its principal effect was to augment epithelialization. (WOUND REP REG 2002;10:295–301)
Mechanism of action of PROMOGRAN, a protease modulating matrix, for the treatment of diabetic foot ulcers
Authors: CULLEN BREDA , SMITH RACHEL , MCCULLOCH ELAINE , SILCOCK DEREK , MORRISON LIBBY
Published: March 2003

Proteases play a critical role in many of the physiologic processes of wound repair. However, if their activity becomes uncontrolled proteases can mediate devastating tissue damage and consequently they have been implicated in chronic wound pathophysiology. Previous studies have shown that chronic wound fluid contains elevated protease levels that have deleterious effects, degrading de novo granulation tissue and endogenous biologically active proteins such as growth factors and cytokines. Therefore, we have proposed that an effective therapeutic approach for chronic wounds would be to modify this hostile environment and redress this proteolytic imbalance. Using an ex vivo wound fluid model, we show the ability of a proprietary new wound treatment to bind and inactivate proteases. We have shown that the addition of this test material to human chronic wound fluid obtained from diabetic foot ulcer patients resulted in a significant reduction in the activities of neutrophil‐derived elastase, plasmin, and matrix metalloproteinase when compared to wet gauze. This study provides mechanistic evidence to support the hypothesis that this novel treatment modality for chronic wounds physically modifies the wound microenvironment, and thereby promotes granulation tissue formation and stimulates wound repair.
P–T–t evidence for mechanisms of vertical tectonic motion in a contractional orogen: north‐western US and Canadian Cordillera
Authors: Whitney  , Miller  , Paterson
Published: March 2003

The >1800 km long Coast Mountains–North Cascades orogen of the Canadian Cordillera and north‐western US developed as a continental magmatic arc. Metamorphic rocks in the orogen contain widespread evidence for burial of supracrustal rocks to depths of c. 40 km, followed by nearly isothermal decompression to depths of <10 km. Near many shallowly‐emplaced, mid‐Cretaceous plutons, low‐pressure contact metamorphic effects were overprinted by high‐pressure regional metamorphic minerals and textures, as evidenced by kyanite±staurolite pseudomorphs after andalusite in metapelitic rocks. Therefore, near‐pluton rocks record the loading history of the orogen. Metapelitic rocks not associated with plutons only preserve evidence for high‐pressure conditions and/or high‐temperature decompression, as indicated, for example, by sillimanite and cordierite after kyanite and garnet, respectively. Petrological evidence for burial and decompression is therefore recorded in different rocks. Various regions of the orogen differ in timing of metamorphism, the overall shape of P–T  paths and the relative timing and regional extent of the high‐pressure event, but most of these data and observations are consistent with thrusting and/or pure shear thickening as primary loading mechanisms throughout the orogen, as opposed to magma‐dominated loading. This interpretation is further supported by comparison with thermal models, which demonstrate that the P–T  paths are consistent with simultaneous thrusting and folding at a high initial geothermal gradient (35–40 °C km−1) in much of the orogen. A high geothermal gradient supports tectonic models invoking intra‐arc contraction and suggests that magmatism played an important role in regional temperature‐time paths. This tectonic‐thermal history may be typical of other contractional orogens and illustrates the importance of large vertical displacement of crust in magmatic arcs.
Evolution of Caledonian deformation fabrics under eclogite and amphibolite facies at Vårdalsneset, Western Gneiss Region, Norway
Authors: Engvik  , Ersen
Published: March 2003

The Vårdalsneset eclogite situated in the Western Gneiss Region, SW Norway, is a well preserved tectonite giving information about the deformation regimes active in the lower crust during crustal thickening and subsequent exhumation. The eclogite constitutes layers and lenses variably retrograded to amphibolite and is composed of garnet and omphacite with varying amounts of barroisite, actinolite, clinozoisite, kyanite, quartz, paragonite, phengite and rutile. The rocks record a five‐stage evolution connected to Caledonian burial and subsequent exhumation. (1) A prograde evolution through amphibolite facies (T =490±63 °C) is inferred from garnet cores with amphibole inclusions and bell‐shaped Mn profile. (2) Formation of L>S‐tectonite eclogite (T =680±20 °C, P=16±2 kbar) related to the subduction of continental crust during the Caledonian orogeny. Lack of asymmetrical fabrics and orientation of eclogite facies extensional veins indicate that the deformation regime during formation of the L>S fabric was coaxial. (3) Formation of sub‐horizontal eclogite facies foliation in which the finite stretching direction had changed by approximately 90°. Disruption of eclogite lenses and layers between symmetric shear zones characterizes the dominantly coaxial deformation regime of stage 3. Locally occurring mylonitic eclogites (T =690±20 °C, P=15±1.5 kbar) with top‐W kinematics may indicate, however, that non‐coaxial deformation was also active at eclogite facies conditions. (4) Development of a widespread regional amphibolite facies foliation (T =564±44 °C, P<10.3–8.1 kbar), quartz veins and development of conjugate shear zones indicate that coaxial vertical shortening and sub‐horizontal stretching were active during exhumation from eclogite to amphibolite facies conditions. (5) Amphibolite facies mylonites mainly formed under non‐coaxial top‐W movement are related to large‐scale movement on the extensional detachments active during the late‐orogenic extension of the Caledonides. The structural and metamorphic evolution of the Vårdalsneset eclogite and related areas support the exhumation model, including an extensional detachment in the upper crust and overall coaxial deformation in the lower crust.
Primary carbonate/CO2 inclusions in sapphirine‐bearing granulites from central Sri Lanka
Authors: Bolder‐Schrijver  , Kriegsman  , Touret
Published: March 2003

High‐density CO2‐rich fluid inclusions from a sapphirine‐bearing granulite (Hakurutale, Sri Lanka) have been studied by microthermometry, Raman spectrometry and SEM analysis. Based on textural evidence, two groups of inclusions can be identified: primary, negative crystal shaped inclusions (group I) and pseudo‐secondary inclusions, which experienced a local, limited post‐trapping modification (group II). Both groups contain magnesite as a daughter mineral, occurring in a relatively constant fluid/solid inclusion volume ratio (volsolid =0.15 total volume). CO2 densities for group I and II differ only slightly. Both groups contain a fluid, which was initially trapped at peak metamorphic conditions as a homogeneous (CO2+MgCO3) mixture. Thermodynamic calculations suggest that such a fluid (CO2+15 vol% MgCO3) is stable under granulite facies conditions. After trapping, magnesite separated upon cooling, while the remaining CO2 density suffered minor re‐adjustments. A model isochore based on the integration of the magnesite molar volume in the CO2 fluid passes about 1.5–2 kbar below peak metamorphic conditions. This remaining discrepancy can be explained by the possible role of a small quantity of additional water.
Regional variation in exhumation and strain rate of the high‐pressure Sambagawa metamorphic rocks in central Shikoku, south‐west Japan
Authors: Yagi K. , Takeshita T.
Published: March 2003

Regional variation in the P–T path of the Sambagawa metamorphic rocks, central Shikoku, Japan has been inferred from compositional zoning of metamorphic amphibole. Rocks constituting the northern part (Saruta River area) exhibit a hairpin type P–T path, where winchite/actinolite grew at the prograde stage, the peak metamorphism was recorded by the growth of barroisite to hornblende and sodic amphibole to winchite/actinolite grew at the retrograde stage. In the southern part (Asemi River area), rocks exhibit a clockwise type P–T path, where barroisite to hornblende core is rimmed by winchite to actinolite. The difference in P–T path could suggest a faster exhumation rate (i.e. more rapid decompression) in the southern than in the northern part. On the other hand, physical conditions of deformation during the exhumation stage have been independently inferred from microstructures in deformed quartz. Recrystallized quartz grains in rocks from the low‐grade (chlorite and garnet) zones are much more stretched in the southern part (aspect ratio ≥ 4.0) than in the northern part (aspect ratio< 4.0), indicating a higher strain rate in the former than in the latter. These facts may indicate that the exhumation and strain rates are correlated (i.e. the exhumation rate increases with increasing the strain rate). The difference in the exhumation rate inferred from amphibole zoning between the northern and southern parts could be explained by an extensional model involving normal faulting, where the lower plate can be exhumed faster than the upper plate due to the displacement along the fault. Furthermore, the model may explain the positive correlation between the exhumation and strain rates, because the lower plate tended to support more stress than the upper plate.
Indications for Vancomycin in Dialysis Patients
Authors: Golper Thomas A. , Schulman Gerald , D'agata Erika M. C.
Published: March 2003

Resistance to vancomycin has emerged among Staphylococcus aureus, coagulase‐negative staphylococci (CNS), and enterococci, and this emergence has particular prevalence in dialysis units. It has therefore become imperative that physicians use vancomycin judiciously. General recommendations regarding the appropriate use of vancomycin have been developed. Although in theory implementation of these guidelines should not be difficult, the medical community may be unable or unwilling to make the necessary adjustments in practice. The onslaught of cost constraints and bureaucratic encumbrance has occurred simultaneously with the increase in vancomycin resistance among pathogens commonly isolated among the dialysis population. When a patient responds to empiric antibiotic therapy and susceptibility data indicate that an antibiotic other than vancomycin would be appropriate, the clinician far too often does not make the change to this alternative. Previously there was no biological imperative to change the antibiotic. That complacency has infected an entire generation of physicians, and especially nephrologists. Furthermore, there is an active movement against change, driven by concerns such as malpractice accusations and frank errors in the interpretation of medical facts.
Role of β2‐Microglobulin in the Immune Response in Renal Osteodystrophy
Authors: Balint Eva
Published: March 2003

Renal osteodystrophy is the major cause of skeletal morbidity in dialysis patients. It is characterized by β2‐microglobulin (β2M) amyloid deposition at the osteoarticular sites and a destructive arthropathy. β2M is present on the surface of all nucleated cells as the small extracellular subunit of the major histocompatibility complex (MHC) class I molecule and actively participates in the immune response. Accumulating evidence suggests that β2M plays a key role in the development of renal osteodystrophy through a T cell‐mediated inflammatory immune mechanism.
How Important Is Atheromatous Renal Artery Stenosis as a Cause of End‐Stage Renal Disease?
Authors: Main John
Published: March 2003

In recent years atheromatous renal artery stenosis has been proposed as a common and potentially preventable cause of end‐stage renal disease (ESRD). Occlusive renal artery disease causes renal failure that can be reversed following successful revascularization, but this scenario is relatively rare. Nonocclusive renal artery stenosis is commonly found in association with varying degrees of renal impairment. However, recent evidence and clinical observation suggest that a cause and effect relationship is unlikely. Experimentally, split renal function studies in cases of unilateral stenosis find similar degrees of renal impairment in both kidneys. Clinically, severe renal impairment is often found in the presence of unilateral stenoses. Another nephropathic process must be going on, probably a combination of hypertensive and atheroembolic damage. It is not surprising that the two pathologies often coexist, in view of their shared causes (principally hypertension and tobacco smoking). Previous studies of the importance of renal artery stenosis in causing ESRD probably included many cases of hypertensive and atheroembolic nephropathy. Unfortunately the potential for renal revascularization to prevent ESRD has been exaggerated.