Search PubMed⌕ Search

Biomedical subjects

G W Cherry

Publications and source records attributed to G W Cherry.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of hypochlorous acid washes in the treatment of chronic venous leg ulcers.

OBJECTIVE: Hypochlorous acid (HOCl) is a highly microbiocidal agent active against bacteria, viruses and fungi. Using quantitative microbiology, preliminary studies showed it achieved an appreciable reduction in the bacterial burden in chronic venous leg ulcers. The study aimed to determine whether it has a role as an additional treatment for chronic venous ulcers that have not healed with conventional treatment. METHOD: On the basis of previous reports we designed a study in which patients acted as their own controls, in that only patients who failed to achieve a 44% reduction in wound size with standard treatment (compression bandaging) received HOCl washes. RESULTS: Of 30 patients admitted to the study, 10 achieved a 44% ulcer reduction after three weeks of standard treatment. In addition to the standard compression treatment, the remaining 20 patients were given HOCl washes over 12 weeks. Of the 20 ulcers, nine (45%) healed and five (25%) reduced in size by over 60%. All patients became free of pain. CONCLUSION: These findings confirm the clinical efficacy of treating venous leg ulcers with hypochlorous washes. Use of HOCl washes as an adjunctive therapy for recalcitrant venous leg ulcers appreciably increases healing and rapidly relieves pain.

Aged↗
PubMed2004

How echographic image analysis of venous oedema reveals the benefits of leg elevation.

OBJECTIVE: Venous insufficiency, leading to venous oedema, is a key pathogenic factor for the non-healing of venous leg ulcers. This study aimed to evaluate the effects of leg elevation on venous oedema. METHOD: Ten patients aged 44-89 years (median: 61) with leg oedema had high-frequency B-mode ultrasound scanning and digital image analysis before and after three to four hours of leg elevation. The echographic image analysis system was used, where oedema is represented by the hypoechogenic part of the image--that is, the total number or density of low echogenic pixels (LEPs) in a particular area. RESULTS: Compared with pre-elevation, the volume of the lower leg decreased by 2.9% +/- 0.6 (138 cm3 +/- 39) after three to four hours' elevation (p < 0.05). After elevation, the LEPs in the upper, middle and lower sites of the limb decreased by 8.8%, 15.6% and 17.3% respectively, reaching statistical significance (p < 0.05) in the lower site. The ratio of LEPs in the upper and lower dermis in the upper, middle and lower sites decreased by 30.3%, 45.8% and 22.5% respectively. This was significant in both the middle and lower sites (p < 0.01). After elevation dermal thickness increased by 0.047 mm, 0.194 mm and 0.232 mm respectively. This change was statistically significant in the middle (p < 0.05) and lower sites of the limb (p < 0.01). CONCLUSION: LEPs are a sensitive marker of dermal oedema and its effects. Leg elevation is extremely effective in reducing oedema, even if only for three to four hours.

Adult↗
PubMed2004

Effect of glucose concentration on the growth of normal human dermal fibroblasts in vitro.

OBJECTIVE: Glucose requirements increase in tissue repair as glucose is an energy source for cell proliferation and the formation of extracellular matrix components. Glucose concentrations in leg ulcer wound fluid are lower than in normal human serum, with a median of 0.7 mM (range: 0.3-1.2 mM). This study investigated the effect of such low concentrations on the growth of fibroblasts in vitro. METHOD: Fibroblasts from 50-year-old and 87-year-old subjects were used. Growth in medium with various concentrations of glucose was determined by a colorimetric assay and microphotography. RESULTS: Up to day 6, there were minimal differences in growth, but after day 6 a clear dose-dependent increase in growth was observed. In the lower dose range (up to 2.3 mM), growth was highly dose-dependent (r2 = 0.981), with an increase of 1.8 mM stimulating cell growth by day 10 up to 163% of the controls (p < 0.0001). Concentrations of 5.5-25.5 mM glucose stimulated cell growth by day 10 to about 210% of the controls (p < 0.0001), with little difference between these concentrations. CONCLUSION: These results suggest that glucose enhancement to cells involved in healing might serve as an adjunctive treatment for chronic wounds.

Aged↗
PubMed2003

The cellular origins of the linear IgA disease target antigens: an indirect immunofluorescence study using cultured human keratinocytes and fibroblasts.

BACKGROUND: Linear IgA disease (LAD) is an IgA-mediated subepidermal immunobullous disease of adults and children, with heterogeneous immunopathology. Objectives To investigate to what extent the cellular origins of the target antigens account for the heterogeneity of the immune response in LAD. METHODS: Forty-nine adult and 33 childhood LAD sera were studied. Immunofluorescence was carried out to determine the expression of the LAD antigens by normal human keratinocytes, fibroblasts and mixed cultures of keratinocytes and fibroblasts. Immunoblotting was performed to determine the localization of the LAD target antigens in tissue extracts (48 adult and 31 childhood sera) and cell extracts (21 adult and 10 childhood sera). RESULTS: Thirty-one adult and 13 childhood LAD sera bound proteins expressed by human keratinocytes; of these sera, 15 adult and four childhood LAD sera also recognized proteins expressed by fibroblasts. A single adult serum was positive on fibroblasts alone. Seventeen adult and 20 childhood sera were negative on both cell types. There was a modest increase (9%) in the detection of the IgA autoantibodies on keratinocytes and fibroblasts grown together in mixed culture. Immunoblotting showed that the LAD target antigens could be detected in cell as well as in tissue extracts. CONCLUSIONS: Our results have shown that normal human keratinocytes and fibroblasts in culture express the LAD target antigens. LAD sera (with a single exception) bound antigens expressed by keratinocytes alone or by both keratinocytes and fibroblasts. The principal pattern of expression in keratinocytes was cytoplasmic, similar to that demonstrated by polyclonal antibodies to the 180-kDa bullous pemphigoid antigen (BP180). This reflects the pivotal role of BP180 in LAD. The finding that LAD antigens are expressed by both human keratinocytes and fibroblasts in culture may explain the heterogeneity of the target antigens, and may be a contributory factor in the immunopathology of the disease.

Adolescent↗
PubMed2003

Effect of intermittent radiant warming on proliferation of human dermal endothelial cells in vitro.

OBJECTIVE: This study investigated the effect of Warm-Up therapy on the proliferation of human microvascular dermal endothelial cells. METHOD: Endothelial cells from an adult subject were seeded in six-well plates and placed in an incubator at 32.5 degrees C. The following day Warm-Up dressings were placed over the plates, with or without warming cards. Cards set at 38 degrees C or 42 degrees C raised the temperature in the medium to maxima of 34.5 degrees C and 37.5 degrees C respectively. Units were switched on daily for three one-hour periods. Cell numbers were counted by haemocytometer. RESULTS: Maximum stimulation of endothelial cell proliferation occurred under the 38 degrees C card, with cells numbering 135-158% of the controls (p < 0.05). the 42 degrees C card also stimulated cells (110-155%) but this did not reach statistical significance. CONCLUSION: The accelerated proliferation of microvascular dermal endothelial cells achieved by intermittent radiant warming may have contributed to the increase in granulation tissue reported previously in our clinic.

Adult↗
PubMed2003

Sensory testing in patients with chronic venous leg ulcers using a 10 g Owen Mumford monofilament.

OBJECTIVE: Chronic venous insufficiency in the lower legs may directly contribute to tissue damage, and there is increasing evidence that neuronal damage may be involved. This study was carried out to determine the feasibility of using a simple neuropathy screening test in the community to diagnose sensory neuropathy in the feet of patients with chronic venous insufficiency. METHOD: We tested 15 randomly selected patients with documented chronic venous insufficiency with the 10 g Owen Mumford monofilament, in order to ascertain objectively sensory blunting. RESULTS: Forty-seven per cent of the patients had normal sensation in the foot of the ulcerated leg and 53% showed some degree of neuropathy. A recent study comparing the performance of commercially available 10 g monofilaments showed that the Owen Mumford filament was one of the most accurate, with 100% buckling within +/- 1 g of 10 g. CONCLUSION: This preliminary study indicates that the 10 g monofilament is an easy method of testing the sensory status of patients with chronic venous insufficiency in the community.

Aged↗
PubMed2002

Effect of a lipopolysaccharide from E. coli on the proliferation of fibroblasts and keratinocytes in vitro.

Studies previously conducted in our laboratory have shown that an extract from the leaves of Chromo-laena odorata is mitogenic for human skin fibroblasts and keratinocytes. However, lipopolysaccharides, sometimes present in plant extracts, can also play a role in cell growth and might have been responsible for or contributed to the mitogenic activity observed. The present study aimed to investigate whether a lipopolysaccharide would have any effect on the proliferation of human fibroblasts and keratinocytes. Cells were seeded in 96-well plates and concentrations from 0.0 to 5.0 microg/mL of lipopolysaccharide in basal or growth medium were added. Cell growth was determined over a period of 10 days using a colorimetric assay. Lipopolysaccharide at concentrations between 0.05 microg/mL and 0.5 microg/mL in the growth medium significantly stimulated fibroblast proliferation after incubation for more than 6 days. In basal medium, more than 8 days of incubation was needed for significant stimulation of growth. Lipopolysaccharide stimulation of keratinocytes was evident at 0.5 microg/mL by day 3 in basal medium and by day 5 in growth medium. Although the lipopolysaccharide did stimulate cell growth it did so only at higher concentrations than were present in our plant extracts and to a lesser degree.

Cell Division↗
PubMed2002

Healing venous ulcers with cycloidal multidirectional vibration therapy.

OBJECTIVE: This preliminary study combined compression bandaging with cycloidal vibration to determine whether this would enhance the rate of healing of venous leg ulceration. METHOD: Twenty-one patients with venous ulceration were enrolled into a 12-week trial. The vibration device was used three times daily for 30 minutes on each occasion, along with compression bandaging. RESULTS: Ulcers of 13 patients (62%) healed within 12 weeks. The remaining eight patients completed the 12-week study with a 31-90% reduction in ulcer size. A reduction in pain was observed in 17 out of 21 patients (81%). Ultrasound measurements showed reduced fluid content in the upper dermis in patients whose ulcers had healed and in others whose ulcers were improving. CONCLUSION: This preliminary study shows that gentle cycloid vibration, combined with standard compression bandaging, enhances the healing rate of venous ulcers and helps to relieve pain.

Aged↗
PubMed2001

Effects of Buddleja globosa leaf and its constituents relevant to wound healing.

An aqueous extract of Buddleja globosa leaves, used traditionally in Chile for wound healing, was tested for the ability to stimulate growth of fibroblasts in vitro and for antioxidant activity in the same fibroblast cell system challenged with hydrogen peroxide. Low concentrations of the extract gave an increase in fibroblast growth which was not statistically significant but cytotoxicity was observed at concentrations greater than 50 microg/ml. The extract showed strong antioxidant effect and fractionation led to the isolation of three flavonoids and two caffeic acid derivatives, each of which was shown to contribute to the antioxidant effect at concentrations below 10 microg/ml. These activities would accelerate the healing of wounds.

Antioxidants↗
PubMed2000

Investigating plant-based medicines for wound healing with the use of cell culture technologies and in vitro models: a review.

INTRODUCTION: Cell culture and molecular technologies are basic yet sophisticated research tool used to investigate plant-based medicine for wound healing. METHODS: Cell viability and proliferation assay is used to determine whether there are any positive effects and to discover what is the limiting cytotoxic concentration in vitro. The scratch technique, fibroblast-populated collagen lattices and aortic rings embedded gels are used as the in-vitro models of wound re-epithelialization, contraction and angiogenesis. The immunofluorescence, immunoblotting and organotypic culture can be used to detect expression of specific proteins that are modulated by plant extracts during the wound healing process. MAIN FINDINGS: Given the dynamics of the wound healing process, cell culture and molecular technologies are advantageous in providing us with detailed studies and analysis of each intricate process. CONCLUSION: The scientific approaches for the study of traditional plant-based remedies for wound healing will provide us an important platform for rigorous testing and evaluation of their clinical efficacy based on accepted rules of evidence.

Cell Survival↗
PubMed1999

The treatment of ambulatory venous ulcer patients with warming therapy.

The standard treatment for ambulatory patients with venous ulcers is compression therapy. The aim of the present study was to develop a warming regimen to treat venous ulcers, which could be easily used by patients in their home or work environment. Five patients with a mean age of 66 years (51-80) who had venous ulcers for an average of 8 months (3-13) were treated with zip-up compression stockings (gradient compression 40 mmHg at the ankle) and a warming dressing. The latter was controlled by the patient to warm the ulcer to 38 degrees C for 1 hour three times daily. Warming therapy was carried out for 2 weeks and patients' ulcers were monitored for healing for 12 weeks. In all but one of the patients following warming therapy, there was marked increase in granulation tissue as well as a decrease in pain. Four of the five patients completely healed during the 12-week period. In conclusion, this study has demonstrated that warming therapy can be used by ambulatory patients with venous ulcers in conjunction with compression therapy. A randomized prospective study is in progress.

Aged↗
PubMed1999

Effect of burn healing liquid on keratinocyte and fibroblast proliferation and on collagen lattice contraction.

OBJECTIVES: To investigate the effect of Burn Healing Liquid (BHL) on the proliferation of keratinocytes and fibroblasts and to explore the potential effect of BHL on fibroblast contraction. METHODS: Human keratinocytes and dermal fibroblasts were cultured in media containing serial dilutions of BHL followed by cell proliferation determination assessed with MTT (3-[4, 5-dimehtylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay at different time intervals. The in vitro collagen lattice contraction model was utilized for determining the contractility of fibroblasts cultured in BHL containing medium. RESULTS: The 1:10(7) dilution of BHL enhanced the growth of both keratinocytes and fibroblasts whereas the 1:10 dilution increased the growth of keratinocytes only. Collagen lattice contraction was inhibited dose-dependently by BHL and such an inhibition could be reversed by switching BHL containing medium to normal medium containing 10% fetal calf serum. CONCLUSION: BHL enhances the growth of both keratinocytes and fibroblasts and reversibly inhibits the fibroblast contraction in collagen lattice.

Burns↗
PubMed1998

Dermal oedema assessed by high frequency ultrasound in venous leg ulcers.

Oedema is considered a key pathogenic factor in the development of venous leg ulcers. The purpose of this study was to determine the localization of oedema in legs with ulcers. Twelve patients with 13 venous leg ulcers (one bilateral), with a duration of 7-18 months, were examined by high-frequency B-mode ultrasound scanner. This was performed at three sites in the leg (low, middle and upper sites of the lower leg). In the same group of patients, the legs without ulcers were used as controls. The echogenicity and the thickness of the whole dermis were quantified by digital image analysis; the echogenicities of the upper (papillary) and lower portions of the dermis were measured. In the upper site no significant difference was found between the legs with ulcers and controls. In the middle and low sites of legs with ulcers, the dermal echogenicities were 34% and 64% (P < 0.01) less than those in controls, and the dermal thicknesses were 0.4 mm and 0.8 mm (P < 0.01) thicker than those in controls, respectively. This indicated intradermal oedema existing in the lower part (gaiter area) of the legs with ulcers. The ratios of low echogenic pixels in the upper and lower portions of the dermis, in the middle and low sites of legs with ulcers, were 0.5 and 0.9 (P < 0.05 and P < 0.01), respectively, higher than those in controls, suggesting the papillary dermis as a preferential site of oedema formation. The present study demonstrates that in the low sites of legs with ulcers, a marked increase in oedema was seen in the papillary dermis. This may add to the understanding of the origin of leg ulcers in the gaiter area of the leg.

Aged↗
PubMed1998

Topical tamoxifen--a potential therapeutic regime in treating excessive dermal scarring?

Abnormal dermal scarring which affects a large number of people is aesthetically disfiguring and can be functionally disabling. Existing medical and surgical strategies to prevent or to treat scars are frequently disappointing and more effective therapies are needed. Tamoxifen, which has been used extensively in the treatment of breast cancer over the last 20 years has recently been shown to inhibit the proliferation of fibroblasts cultured from keloid biopsies. Successful treatment of retroperitoneal fibrosis and desmoid tumours with tamoxifen has also been reported. We have investigated the potential of tamoxifen as an inhibitor of wound contraction, using fibroblast-populated collagen lattices as an in vitro model. From these studies we postulate that tamoxifen may have potential clinical significance in the treatment of abnormal scarring. Normal adult human skin fibroblasts were embedded within type I collagen, then medium either with or without addition of tamoxifen was added to the collagen lattices. Lattice diameters were measured at intervals to assess the influence of tamoxifen on the lattice contraction. The reversibility of the inhibitory effect of tamoxifen on lattice contraction was investigated by 'washing out the tamoxifen' at different time-points. To visualise changes in the morphology of fibroblasts MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] was added to the lattices. Tamoxifen at 1 and 5 microM had no significant influence on lattice contraction but higher concentrations of 50 and 100 microM completely inhibited contraction. At intermediate concentrations from 10 to 20 microM the degree of lattice contraction was dose-dependent. The reversibility of the inhibition was both dose- and time-dependent. Both the inhibition of contraction and the reversibility of inhibition appeared to correlate with changes in fibroblast morphology. The dose- and time-dependent inhibition of contraction by fibroblasts suggests that tamoxifen could be investigated as a novel potential therapeutic agent in treating abnormal dermal scarring.

Adult↗
PubMed1998

Laser Doppler imaging of skin microcirculation.

Laser Doppler imaging (LDI), a new technique which allows measurement of skin blood perfusion at a distance from the skin surface, was assessed methodologically in healthy volunteers. Each skin LDI value was based on virtually real-time measurements obtained from a number of discrete measuring sites. In scans made along the circumference of the lower arm, valid figures for LDI (as distinct from no output at all) were obtained in 8/8 measurements at 0 degrees inclination, and in 16/16 measurements at 7 degrees, 14 degrees, 22 degrees, 30 degrees and 38 degrees, respectively. Beyond this inclination a numerical output was obtained in only 9/16 of measurements at an inclination of 48 degrees, in 7/16 at 69 degrees, and in no more than 1/16 at 90 degrees. Values obtained at angles of inclination greater than 38 degrees fell within the relatively narrow range of values obtained at lesser angles of inclination. The findings are of interest since measuring sites of clinical importance may not be flat. Variability of measurement (coefficient of variation in per cent) was studied in the lower leg by performing LDI and conventional laser Doppler flowmetry (LDF) concomitantly. The coefficient of variation for measurements in one subject at rest was 13% for LDI vs. 19% for LDF, the corresponding interindividual coefficient of variation values being 25% vs. 28%. In response to heating, finger pulp perfusion increased by 55% as measured by LDI (p = 0.0051) and by 44% (p = 0.0756) as measured by LDF. In summary, the findings contribute to the validation of LDI for skin perfusion measurement.

Adolescent↗