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B Nedelec

Publications and source records attributed to B Nedelec.

17 recordsLinked to original sources

Upregulation of rat P23 (a member of the YjgF protein family) by fasting, glucose diet and fatty acid feeding.

In a previous study, we identified and purified a 99-amino-acid rat liver-kidney perchloric-acid-soluble 23-kDa protein (P23) which displays 30% identity with a highly conserved domain of heat shock proteins (HSPs), as well as an AT-rich 3' untranslated region, which has also been described to play a role in H70 mRNA life span and protein expression. An identical perchloric-acid-soluble protein inhibiting protein synthesis in a rabbit reticulocyte lysate system was also found 2 years later by another group. More recently, the novel, the YjgF, protein family has been described, comprising, 24 full-length homologues, including P23, highly conserved through evolution, and consisting of approximately 130 residues each and sharing a common ternary structure. Independent studies from different laboratories have provided various hypothetical functions for each of these proteins. The high degree of evolutionary conservation may suggest that these proteins play an important role in cellular regulation. Although the function of none of these proteins is known precisely, we present experimental evidence which, combined with the relationship to glucose-regulating protein revealed here, and the relationship to fatty-acid-binding protein revealed by others, allow us to propose a role for P23. In rat liver, P23 expression is developmentally regulated and modulated by dietary glucose, and its mRNA is induced by starvation, in the presence of fatty-acids and in 3-MeDAB-induced hepatomas. The mRNA encoding mouse liver P23 is also hormonally modulated in a mouse line AT1F8. These data indicate that P23 protein might be a key controller of intermediary metabolism during fasting.

Animals↗

Interleukin 1 gene cluster polymorphisms in multiplex families with spondylarthropathies.

Interleukin 1alpha (IL-1alpha) has been implicated in the pathogenesis of infectious, auto-immune and inflammatory diseases. Polymorphisms in the genes encoding IL-1alpha, IL-1beta and the IL-1 receptor antagonist (ILRN) molecules have been associated with several inflammatory diseases. As the marker D2S160 has been characterized as a candidate locus for Ankylosing Spondylitis (AS) after a genome-wide scan, and since this locus is located approximately 0.3 cM telomeric to the IL-1 gene cluster, we hypothesized that these cytokines might be good candidates for Spondylarthropathies (SpA). Therefore we tested this hypothesis using the transmission disequilibrium test (TDT) in 37 families representing 217 subjects from three intragenic IL-1 gene cluster polymorphisms, the IL1B Taq I, the ILRN 2nd intron, and the IL1A Nco I, taking HLA B27 status into account or not. In conclusion, by means of intra-familial TDT analysis we found no linkage or intra-familial association between SpA and the three IL-1 gene-cluster polymorphisms in SpA multiplex family material.

Adult↗

Myofibroblasts and apoptosis in human hypertrophic scars: the effect of interferon-alpha2b.

BACKGROUND: Hypertrophic scars (HSc) are a dermal fibroproliferative disorder that leads to considerable morbidity. Preliminary evidence suggests that interferon (IFN) may improve HSc clinically. The aims of this study were (1) to compare the cell density in HSc and in wounds that heal without the development of HSc (normotrophic scars), (2) to examine the presence of myofibroblasts and apoptosis in normotrophic and HSc scars over time, and (3) to determine if the systemic administration of IFN-alpha2b can induce apoptosis. METHODS: Two groups of patients underwent serial tissue biopsies. Six burn patients were studied prospectively by obtaining biopsy specimens from wound granulation tissue, normal skin, post-burn HSc, and normotrophic scars (healed donor sites). A second patient group with HSc was treated with systemic IFN-alpha2b and had biopsy material taken before, during, and after IFN therapy. The tissue was analyzed by immunohistochemical staining for alpha-smooth muscle actin (alpha-SMA) and in situ DNA fragmentation terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay for apoptosis. RESULTS: The total numbers of fibroblasts in HSc were found to be similar to granulation tissue and twice that of normal skin and normotrophic scar. Over time the numbers of cells in HSc tissue decreased toward normal skin levels. There was a significantly higher percentage of fibroblasts staining for alpha-SMA in HSc as compared with normotrophic scar or normal skin obtained from the same patient (P >.05). Serial biopsy specimens of resolving HSc tissue obtained from the patients who received systemic IFN-alpha2b showed a general reduction in total number of fibroblasts and myofibroblasts associated with a significant increase in the percentage of apoptotic cells compared with normal dermis from the same patient. CONCLUSIONS: HSc tissues have greater numbers of fibroblasts and myofibroblasts than normal skin and normotrophic scars. As HSc remodels, the numbers of fibroblasts and myofibroblasts reduces, possibly by the induction of apoptosis. Systemic IFN-alpha2b may contribute to the resolution of HSc in part by the enhanced induction of apoptosis.

Actins↗

Delayed appearance of decorin in healing burn scars.

AIMS: We have previously shown that hypertrophic scar tissue from burn patients contains abnormally high amounts of the proteoglycans versican and biglycan and reduced amounts of decorin, in comparison with normal dermis or mature scar. The lack of decorin may account for the poor organization of collagen fibrils in the nodular areas of these scars. Decorin has also been reported to neutralize the fibrogenic growth factor TGF-beta1. This study was conducted to monitor the time-course of expression of decorin in healing burn wounds by in-situ hybridization to determine whether its absence from hypertrophic scars could result from reduced synthesis. METHODS AND RESULTS: Scar tissue from 19 patients and normal dermis from six patients, was fixed in paraformaldehyde, embedded in paraffin and sectioned. Digoxigenin-labelled cRNA probes were prepared from a plasmid containing a 622-bp insert of human decorin cDNA and used for in-situ hybridization. Total numbers of connective tissue cells and cells positive for decorin mRNA were counted in 10 random fields in the upper (papillary), middle and lower (reticular) one-thirds of the dermis. In all regions the number and percentages of cells with decorin mRNA were low during the first 12 months after injury (eight samples), much higher between 12 and 36 months (seven samples) and low and similar to those in normal skin after 36 months (five samples). The differences between intermediate and early or late stage samples were statistically significant (one-way ANOVA). Immunohistochemistry showed little staining for decorin in early stage samples and much stronger staining in mid-stage. Late stage tissue showed intense staining for decorin, almost comparable to that in normal dermis. CONCLUSION: Expression of decorin in burn wounds is suppressed for about 12 months and then increases at a time when resolution of hypertrophic scarring is generally considered to occur.

Adult↗

Decreased serum insulin-like growth factor-I in burn patients: relationship with serum insulin-like growth factor binding protein-3 proteolysis and the influence of lipid composition in nutritional support.

OBJECTIVES: To test the effects of the amount and type of fat in the nutritional support on serum insulin-like growth factor (IGF)-I concentrations in burn patients and to test the hypothesis that the serum proteolytic activity for insulin-like growth factor binding protein (IGFBP)-3 is a major mechanism for the decreased serum IGF-I observed in these patients. DESIGN: Randomized, double-blind trial of three different nutritional supports and analysis of serum IGF-I, IGFBP-3, and serum IGFBP-3 proteolysis. SETTING: Burn center in a university hospital. PATIENTS: A total of 23 severely burned (>25% total body surface area burned) adult patients. INTERVENTIONS: Patients were randomly assigned to three types of nutritional support differing in the amount of energy derived from fat and the presence or absence of fish oil: Group I (control), 35% fat; Group II, 15% fat; Group III, 15% fat with 50% as fish oil. Nutritional support was both parenteral and enteral and was started within 24 hrs of admission. MEASUREMENTS AND MAIN RESULTS: Serum IGF-I and IGFBP-3 were measured by radioimmunoassay every 3 days for 28 days in 23 severely burned adults. In six patients, IGFBP-3 was measured by ligand binding assay and the serum proteolytic activity for rhIGFBP-3 was measured as well. Serum IGF-I concentration was low in all subjects throughout the study period, but did increase with time (p < .01); significantly higher values were found in Group III (p < .05). Multivariate analysis showed that fish oil and low fat solutions were significantly correlated to serum IGF-I concentrations. Serum IGFBP-3 (radioimmunoassay) was higher than normal throughout the study with no difference between the groups. Between days 4 and 16, IGFBP-3 was cleaved into two fragments in all patients studied, and the molecular weights of the fragments were equal to those observed in the serum of a woman late in pregnancy. During this period of time, serum proteolytic activity for rhIGFBP-3 was >30% in 24 of the 30 samples measured, whereas 20 of the 28 samples measured thereafter were normal (<25%). Serum IGFBP-3 concentration from ligand binding assay was correlated with serum proteolytic capacity in all subjects (mean r2 = 0.77; p < .01) and with serum IGF-I concentrations in five of six subjects (mean r2 = 0.81; p < .01). CONCLUSIONS: In burn injury, serum IGF-I concentrations are sensitive to the amount and type of fat in their nutritional support. The presence of fish oil allowed for a more rapid recovery of serum IGF-I levels. The proteolysis of IGFBP-3 may be an important cause of the decreased serum IGF-I values and the protease(s) responsible for this seem to be similar to those observed in late pregnancy.

Adult↗

Control of wound contraction. Basic and clinical features.

Although a substantial amount of molecular and cellular data have been generated in an effort to understand the process of wound contraction and scar contracture formation, questions remain. What seems apparent is that the myofibroblast is not the only cell that generates contractile forces within wounds, but it does appear to be intrinsically linked to the development of hypertrophic scars. The supposition that the formation of scar contractures is solely the result of a continuation of wound contraction is an oversimplification. Figure 4 provides a model of the possible evolution of contractile forces during the wound healing process and their role in the development of scar contractures. Migration of fibroblasts into and through the extracellular matrix during the initial phase of wound healing, prior to the expression of alpha-SMA, appears to be a fundamental component of wound contraction. During this migration, the pulling of collagen fibrils into a streamlined pattern in their wake, and the associated production of collagenase, may facilitate a more normal arrangement of collagen. Once the wound has been repopulated and the chemotactic gradient that was established by inflammatory cells is decreased, fibroblast migration will cease. It is at this point that myofibroblasts appear and play a key role in the production of hypertrophic scars, given that their prolonged presence and over-representation are hallmarks of this pathology. One of the pivotal differences between wounds that proceed to normal scar compared with those that develop hypertrophic scars and scar contractures may be a lack (or late induction) of myofibroblast apoptotic cell death. The combined contribution of fibroblasts and myofibroblasts to abnormal extracellular matrix protein production results in an excessive and rigid scar. The isometric application of contractile forces by myofibroblasts probably contributes to the formation of the whorls, nodules, and scar contractures characteristic of hypertrophic scars. Because the prolonged presence of myofibroblasts, producing an imbalance in extracellular matrix proteins and proteases, probably exacerbates hypertrophic scars and wound contraction, accelerating the rate of apoptotic cell death to reduce the cell number to that seen in normal scar may be a useful strategy for providing effective and efficient treatment of scar contracture.

Cicatrix, Hypertrophic↗

Transforming growth factor-beta in thermally injured patients with hypertrophic scars: effects of interferon alpha-2b.

Hypertrophic scarring is a common dermal fibroproliferative disorder that leads to poor quality wound healing, prolongs rehabilitation, and increases morbidity following major thermal and other injuries to the deep dermis. Local and systemic transforming growth factor (TGF)-beta has been implicated as a fibrogenic cytokine in the pathogenesis of many fibrotic disorders, whereas interferon (IFN) alpha-2b may improve the pathologic features of dermal fibrosis directly or by antagonizing the effects of TGF-beta and histamine. Nine patients with severe hypertrophic scarring were evaluated for 8 weeks before treatment with subcutaneous recombinant IFN alpha-2b, 2 x 10(6) IU three times per week for 24 weeks. Clinical assessment was performed using standardized photography, a burn scar assessment tool, and serial scar volume measurements. Monthly measurements of serum TGF-beta and plasma Ntau-methylhistamine were made prior to, during, and after IFN alpha-2b therapy and compared with 27 age-matched controls. Serial biopsies of the hypertrophic scars and normal skin were performed for evaluation of mast cell numbers. Significant improvement in scar assessment occurred in 7 of 9 patients, and 3 of 9 demonstrated significant reductions in scar volume with interferon therapy beyond that occurring during the 8-week control period. For the entire group, mean rates of improvement were significantly better during interferon therapy with no recurrence following treatment. Before interferon therapy, serum TGF-beta was significantly higher in the burn patients with hypertrophic scarring than in a control population (123.04 +/- 36.48 vs. 56.85 +/- 8.38 ng/ml, p < 0.05). Within 3 months of IFN alpha-2b therapy, serum TGF-beta levels fell significantly and remained within the normal range during therapy and after interferon therapy was stopped. Plasma Ntau-methylhistamine levels were also significantly elevated in the hypertrophic scar patients as compared with age and sex-matched controls (153.6 +/- 92.07 vs. 48.3 +/- 28.9 pg/ml, p < 0.05), and significant reductions were achieved with interferon therapy and maintained after interferon was discontinued. Paired biopsies of hypertrophic scarring and normal tissue demonstrated increased numbers of mast cells in hypertrophic scars compared with normal uninjured skin from the same patients (2.65 +/- 1.63 vs. 1.04 +/- 0.62 cells/high power field, p < 0.001); however, no significant change in mast cell content of the hypertrophic scars accompanied interferon therapy. Patients with severe hypertrophic scarring demonstrate increased levels of serum TGF-beta and plasma Ntau-methylhistamine following thermal injury. A significant clinical improvement in scar quality and volume occurred during IFN alpha-2b therapy, which was associated with normalization of serum TGF-beta and plasma Ntau-methylhistamine levels. A double-blind, placebo-controlled trial will be required to further assess the usefulness of subcutaneous treatment with IFN alpha-2b for the treatment of hypertrophic scarring.

Adult↗

Hypertrophic scars, keloids, and contractures. The cellular and molecular basis for therapy.

Keloids, hypertrophic scars, and contractures are a result of aberrations of the normal wound healing process. An understanding of the cellular and molecular events that are implicated in the development of these fibroproliferative disorders will allow for optimization of wound healing. In turn, treatment choices can be based on the most current scientific information available.

Adult↗

Genotypic diagnosis of familial Mediterranean fever (FMF) using new microsatellite markers: example of two extensive non-Ashkenazi Jewish pedigrees.

Familial Mediterranean fever is an autosomal recessive disease characterised by multiple attacks of serosal inflammation in the absence of treatment. In the absence of timely diagnosis, renal amyloidosis is a life threatening complication. The diagnosis is often missed because no specific test is available. Early colchicine treatment prevents attacks and renal complications. The FMF gene (MEF) has been mapped to chromosome 16p 13.3 but has not yet been identified. We compared the suitability of a series of microsatellite markers (four of them were new) and propose the routine use of seven of these markers, exhibiting alleles in strong linkage disequilibrium with the disease and informative in 100% of diagnosed patients. Moreover, the discovery of a homozygous status for the 3-3-9 (or 3-3-18) haplotype at the core loci (D16S3070, D16S3082, and D16S3275), which was found in 73% non-Ashkenazi Jewish patients, points to a diagnosis of FMF, even in sporadic cases, with a risk of error of only 2.10(-5). Two extensive pedigrees covering most indications for genetic counselling are presented, showing that it is now possible both prospectively and retrospectively to identify members likely to have MEF mutations. With the help of this accurate test, colchicine treatment can be better targeted, especially where the symptomatology is mild or atypical.

Chromosome Mapping↗

Collagenase production is lower in post-burn hypertrophic scar fibroblasts than in normal fibroblasts and is reduced by insulin-like growth factor-1.

We recently demonstrated that the accumulation of extracellular matrix in post-burn hypertrophic scarring (HSc) tissues is, in part, caused by an overexpression of mRNA for fibronectin, type I, and type III procollagen. Here, we report that five different fibroblast cell strains derived from HSc tissues are deficient in collagenase activity relative to paired fibroblasts from normal skin of the same patients. Quantitative analysis demonstrated significantly lower (52.5 +/- 16.8% vs 100 +/- 8.3%; n = 9; p < 0.05) collagenase activity in conditioned medium from HSc fibroblasts relative to that obtained from the control. The expression of collagenase mRNA was also significantly depressed (51 +/- 7% vs 100 +/- 11%; n = 5; p < 0.05) in four of five strains of HSc fibroblasts examined. The level of mRNA for collagenase in both HSc and normal fibroblasts increased with serial passage, but at any given passage number, the expression of this transcript was lower in HSc fibroblasts. Insulin-like growth factor 1 (IGF-1), which is present at the site of HSc in high quantity, reduced collagenase mRNA but increased type I collagen mRNA expression in a time-dependent manner. The collagenase activity in conditioned medium derived from IGF-1-treated normal dermal fibroblasts was reduced (23.1 +/- 7.81% vs 100 +/- 6.6%; n = 7; p < 0.05). A significant reduction in collagenase mRNA and activity was also found in HSc fibroblasts following IGF-1 treatment. These findings suggest that IGF-1-induced suppression of collagenase mRNA and activity may be a mechanism by which IGF-1 promotes the development of post-burn HSc.

Adolescent↗

Enhanced expression of mRNA for insulin-like growth factor-1 in post-burn hypertrophic scar tissue and its fibrogenic role by dermal fibroblasts.

Hypertrophic scarring (HSc) which frequently develops in patients following severe thermal injury is characterized by accumulation of extracellular matrix (ECM) proteins including type I and type III collagen. In this study, we examined the presence and quantity of IGF-1 mRNA transcripts in post-burn HSc. The results of dot blot experiments showed a 77.5% (100 +/- 8.15 vs 177.5 +/- 19, p < 0.01) increase in expression of IGF-1 IIIRNA in HSc tissue relative to normal dermis obtained from the same patients. A Northern blot analysis confirmed the specificity of the IGF-1 cDNA. This cDNA visualized four different transcripts with apparent sizes of 7.0, 3.9, 1.8 and 1.0 kb, similar to those previously reported. The possible fibrogenic role of IGF-1 was examined by analyzing the effect of this growth factor on the expression of mRNA for the pro alpha 1(I) chain of type I procollagen and the pro alpha 1(III) chain of type III procollagen in dermal fibroblasts. IGF-1 increased the expression of these transcripts as early as 6 h and the effect was maximal at 24 h. Quantitative analysis by densitometry showed a 149 and 166% increase in pro alpha 1(I) and pro alpha 1(III) mRNA after 24 h of IGF-1 treatment, respectively. This effect seems to be specific as the abundance of mRNA for the pro alpha 2(I) chain of type I procollagen or TIMP-II was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

The effect of interferon alpha 2b on the expression of cytoskeletal proteins in an in vitro model of wound contraction.

Wound contraction is an essential component of wound healing. However, the development of scar contractures in tissues and organs disrupts normal organ integrity and produces functional deformities. Although interferons alpha and gamma inhibit extracellular matrix protein production by fibroblasts, their effects on cytoskeletal protein mediated-wound contraction are as yet unclear. The fibroblast-populated collagen lattice is an in vitro assay that simulates wound contraction. When matched pairs of human hypertrophic scar and normal dermal fibroblast cultures established from patients recovering from a thermal injury were used, interferon-alpha 2b exposure before lattice formation was found to significantly inhibit contraction in a treatment time-dependent manner (p < 0.05). Fibroblasts generated contractile forces that were triphasic and serum sensitive (p < 0.01). Comparison of hypertrophic scar and normal dermal fibroblasts revealed no significant differences in ability to induce lattice contraction. Northern blot analysis of mRNAs for the intracellular contractile proteins revealed that interferon-alpha 2b significantly down-regulated mRNA levels of the actin isoforms beta and gamma (50% to 60%) but had no significant effect on alpha-tubulin, vimentin, and alpha-actinin. Fibroblast-populated collagen lattices were stained with rhodamine-labeled phalloidin to reveal filamentous actin proteins. Marked morphologic alterations of the stress fibers were associated with reductions in lattice contraction after interferon-alpha 2b treatment. Thus interferon-alpha 2b's inhibition of wound contraction in vitro is associated with reductions in mRNA for beta and gamma actin and distinct morphologic alterations in fibroblast stress fiber morphology.

Adolescent↗

Characterization, purification and cDNA cloning of a rat perchloric-acid-soluble 23-kDa protein present only in liver and kidney.

A novel protein was extracted with 5% perchloric acid from rat liver and kidney. It is absent from other rat organs. Its apparent molecular mass is 23 kDa as determined by HPLC gel filtration. A single band, corresponding to 10 kDa, was observed after SDS/PAGE, suggesting that the protein consists of two subunits with similar molecular masses. This protein can neither be phosphorylated by ATP, nor acetylated. The sequence of the cDNA encoding this protein was determined. Southern-blot analysis showed that the corresponding gene spanned at least 10 kb and contained at least five introns. Zoo-blot analysis at medium stringency strongly suggests that the gene has been conserved during evolution. The amino-acid sequence of this protein with a highly conserved region is similar to that of a heat-shock protein.

Amino Acid Sequence↗

Interferons gamma and alpha-2b differentially regulate the expression of collagenase and tissue inhibitor of metalloproteinase-1 messenger RNA in human hypertrophic and normal dermal fibroblasts.

We have recently shown that both interferon gamma (gamma) and interferon alpha-2b (alpha-2b) markedly depress the expression of messenger RNA for type I procollagen and fibronectin in postburn hypertrophic scar and normal dermal fibroblasts. In this article we examine the effects of these cytokines on the expression of mRNA for collagenase and its natural inhibitor, tissue inhibitor of metalloproteinase-1. Twelve different fibroblast cell strains, six from postburn hypertrophic scar and six from the normal dermis of the same patients, were established in cell culture. The results of a dose response experiment showed increases in collagenase mRNA up to 4000 U/ml of interferon-alpha-2b, but maximal increases in tissue inhibitor of metalloproteinase mRNA expression and maximal decrease in mRNA for type I procollagen at 2000 U/ml. For subsequent experiments cells were treated with either interferon-alpha-2b (2000 U/ml) or -gamma (1000 U/ml) for 96 hours. Quantitative analysis showed increases in tissue inhibitor of metalloproteinase-1 and collagenase mRNA (81% and 54%, respectively) in interferon-alpha-2b-treated hypertrophic scar fibroblasts. Under the same experimental conditions, interferon-alpha-2b had similar effects on normal dermal fibroblasts; however, interferon-gamma had a differential effect on the expression of mRNA for collagenase and tissue inhibitor of metalloproteinase-1. Cells treated with interferon-gamma showed increases in tissue inhibitor of metalloproteinase-1 mRNA (78% in hypertrophic scar and 56% in normal dermal fibroblasts) but decreases (59% and 42%, respectively) in collagenase mRNA. These effects appear to be selective because rehybridization of blots with a complementary DNA for tissue inhibitor of metalloproteinase-2 mRNA showed no marked alteration in the abundance of this transcript. Significantly greater collagenase activity was found in conditioned medium from interferon-alpha-2b-treated hypertrophic scar cells compared with that from interferon-gamma-treated cells. These findings suggest that interferon alpha-2b would have some advantages over interferon-gamma for the treatment of dermal fibroproliferative disorders, such as postburn hypertrophic scar.

Journal Article↗

Effect of interferon-alpha2b on guinea pig wound closure and the expression of cytoskeletal proteins in vivo.

Scar contraction following the healing of deep partial-thickness or full-thickness dermal injury is a leading cause of functional and cosmetic morbidity. The therapeutic use of interferon for the treatment of fibroproliferative disorders associated with scar contraction, including hypertrophic scar, has been suggested because of its antifibrotic properties. Treatment of fibroblasts with interferon has been shown to reduce the rate and extent of contraction using the in vitro fibroblast-populated collagen lattice model. In order to establish the effect of interferon-alpha2b on full-thickness wound contraction in vivo, osmotic pumps loaded with interferon or sterile saline were implanted intraperitoneally in guinea pigs. Seven days following implantation, six full-thickness punch biopsy wounds were created and were monitored by daily assessment of the wound. There was a significant reduction in the rate of wound contraction in the interferon-treated animals after day 3 (p < 0.01). Western blot analysis was used to quantitate selected cytoskeletal proteins in the normal skin and tissue biopsied from the wound at days 7, 14, and 21 postinjury. The amount of vimentin in the contracted wound increased following injury as compared with the amount present in normal skin (p < 0.0001); however, the relative amounts of the myofibroblast-associated cytoskeletal proteins alpha-smooth muscle actin and smooth muscle myosin were less than those found in normal, uninjured skin. By using vimentin to adjust the levels of cytoskeletal proteins for the increase in cellularity in the wounds, both alpha-smooth muscle actin and smooth muscle myosin significantly increased after closure of the wounds on day 14, as compared with the open-wound stage (day 7), before further reductions occurred with remodeling on day 21. Measurement of apoptotic cells using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay revealed an increase in apoptosis in the interferon-alpha2b-treated animals at 21 days following wounding (p < 0.001), which did not colocalize with alpha-smooth muscle actin staining. Taken together, these findings suggest that interferon-alpha2b inhibits wound contraction in vivo, not through an appreciable alteration in myofibroblast number or cytoskeletal protein expression, but possibly through a reduction in fibroblast cellularity by the induction of apoptosis.

Angiogenesis Inhibitors↗

Rating the resolving hypertrophic scar: comparison of the Vancouver Scar Scale and scar volume.

The increased focus of research interests and clinical documentation on outcomes demands that evaluation tools provide reliable and valid data. The Vancouver Scar Scale (VSS) was developed to provide a more objective measurement of burn scars; however, the validity (a test's ability to measure the phenomenon for which it was designed) of the VSS has not been tested. To examine the construct validity of the VSS, we compared it with scar volume, which has established face validity. Burn scars were evaluated monthly for a minimum of 7 months. Three scar volume measurements were performed on each scar. In addition, 3 independent examiners completed the VSS for the same scar. The data generated by these 2 measurements were used to establish the following: (1) the interrater agreement estimated by interclass correlation coefficient, (2) convergence validity, (3) the sensitivity of the assessments to discriminate changes in the scar over time, and (4) the prevalence of related parameters that are not currently being captured by the VSS. In an attempt to address some of the deficiencies of the VSS, we propose several modifications. We anticipate that these changes will increase the reliability and validity of the VSS through an increase in the awareness that training in the use of this scale is required, through improvement in the quality of the subscales, and through the documentation of additional pertinent information.

Burns↗