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Pornprom Muangman

Publications and source records attributed to Pornprom Muangman.

14 recordsLinked to original sources

PubMed2026

High-Dose Intravenous Vitamin C and Mortality and Organ Dysfunction in Severe Burn Injury: The VICTORY Randomized Clinical Trial.

IMPORTANCE: Severe burn injury triggers systemic inflammation that can lead to multiple organ dysfunctions and death. High-dose intravenous vitamin C has been proposed to mitigate these effects, but strong evidence in patients with burn injury is lacking. OBJECTIVE: To evaluate the efficacy of high-dose intravenous vitamin C in patients with severe burn injury. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind, placebo-controlled phase 3 trial conducted across 24 burn centers in North, Central, and South America; Europe; and Asia. Adults (≥18 years) with deep second- and/or third-degree burns covering 20% or more of total body surface area and requiring skin grafting were enrolled between August 18, 2020, and September 12, 2025. Final follow-up was completed in March 2026. The trial was stopped early after the first prespecified interim analysis for futility/harm. INTERVENTIONS: Patients were randomly assigned (1:1) to receive intravenous vitamin C (50 mg/kg every 6 hours for 96 hours) or matched placebo. MAIN OUTCOMES AND MEASURES: The primary outcome was a composite of 28-day mortality and persistent organ dysfunction (defined as dependence on mechanical ventilation, kidney replacement therapy, or vasopressor/inotrope support at day 28). The main secondary outcome was time to discharge alive from hospital within 90 days. RESULTS: Among 238 patients enrolled (mean age, 48.9 [SD, 19.1] years; 79% male; mean total body surface area, 37.0% [SD, 14.6%]), 120 were assigned to vitamin C and 118 to placebo. The primary composite outcome occurred in 49 patients (40.8%) in the vitamin C group and 35 patients (29.7%) in the placebo group (adjusted risk ratio [RR], 1.28 [95% CI, 0.99-1.65]; P = .06), crossing the prespecified futility/harm threshold and prompting early trial termination. Time to discharge alive from hospital within 90 days was not improved (adjusted subdistribution hazard ratio, 0.85 [95% CI, 0.62-1.16]; P = .31). Twenty-eight-day mortality was higher in the vitamin C group (15.0% vs 7.6%; adjusted RR, 1.96 [95% CI, 1.32-2.90]; P = .001), as was hospital mortality (23.3% vs 16.1%; adjusted RR, 1.44 [95% CI, 1.03-2.00]; P = .03). CONCLUSIONS AND RELEVANCE: Among patients with severe burn injury, high-dose intravenous vitamin C did not reduce 28-day mortality and persistent organ dysfunction and is possibly harmful. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04138394.

Humans↗

PubMed2006

Histology of the thick scar on the female, red Duroc pig: final similarities to human hypertrophic scar.

The etiology and treatment of hypertrophic scar remain puzzles even after decades of research. A significant reason is the lack of an accepted animal model of the process. The female, red Duroc pig model was described long ago. Since the skin of the pig is similar to that of humans, we are attempting to validate this model and found it to be encouraging. In this project we quantified myofibroblasts, mast cells and collagen nodules in the thick scar of the Duroc pig and compared these to the values for human hypertrophic scar. We found the results to be quite similar and so further validated the model. In addition, we observed that soon after wounding an inflammatory cell layer forms. The thickness of the inflammatory layer approaches the thickness of the skin removed as if the remaining dermis "knows" how much dermis is gone. In deep wounds this inflammatory layer thickens and this thickness is predictive of the thickness of the ultimate scar.

Adolescent↗

PubMed2006

Complex wound management utilizing an artificial dermal matrix.

The benefits of the Integra Dermal Regeneration Template in the management of extensive burn injuries have been well documented. Integra can reduce donor- and graft-site scarring and has been reported to be capable of vascularizing over small areas of exposed bone and tendon. Given these potential advantages, we have used Integra for a variety of other reconstruction applications. We performed a retrospective review of patients with complex wounds treated with Integra at our burn center. Integra was used in the management of a variety of wounds, including necrotizing fasciitis, extremity degloving injury, meningococcemia, Marjolin ulcer, postburn lip reconstruction, and fourth-degree burns with exposed bone or tendon. Engraftment rates of Integra and autograft were 98% +/- 4% and 97% +/- 4%, respectively. All areas of graft loss healed without need for regrafting. The benefits of Integra in the management of acute burn wounds can be extended to other traumatic and complex wounds.

Adolescent↗

PubMed2006

Correlation of clinical outcome of integra application with microbiologic and pathological biopsies.

BACKGROUND: Integra, a dermal replacement template consisting of bovine collagen, chondroitin-6-sulfate, and a silastic sheet is a postexcisional treatment for deep partial to full thickness burns where autograft is limited. This study correlates Integra histology and quantitative microbiology cultures with clinical outcomes after autografting. METHODS: Charts of 29 burn patients who underwent Integra treatment and neodermis biopsy at the time of ultra thin autografting were reviewed. We analyzed microbial contamination, inflammatory reaction, and autograft take. RESULTS: The mean burn size and age were 43% total body surface area and 39 years old, respectively. In quantitative neodermis cultures, 90% of samples had bacterial growth; nine samples (31%) had > 10(5) colony forming units per gram. The most common organism was Staphylococcus aureus (31%). Patients with quantitative bacterial counts >10(5) CFU/g received targeted systemic antibiotics. Integra take (83%) and autograft take (92%) were acceptable even in patients with high bacterial counts (78% Integra take; 86% autograft take). More than 50% of biopsies had dermal regeneration similar to normal dermis; foreign body reactions were unusual. Histologic evidence of inflammation, especially polymorphonuclear cells, was increased in biopsies with high bacterial counts. CONCLUSION: Integra and autograft take can be acceptable even with high bacterial counts if wounds are treated with appropriate targeted topical and systemic antibiotics in the presence of microbial contamination. Neodermis biopsies showed fibrous in-growth congruent with existing Integra fibers with minimal foreign body reaction. These data support Integra use as a safe and effective treatment modality in patients with major burns.

Administration, Topical↗

PubMed2006

The optimal time for early excision in major burn injury.

INTRODUCTION: Early excision and grafting (E&G) drastically changed burn care in America by reducing morbidity, mortality and hospital length of stay (LOS). The present study was intended to determine whether an optimal time window exists between resuscitation and wound sepsis for the first E&G in a patient with a large burn. MATERIAL AND METHOD: The authors conducted a retrospective study of patients admitted between January 1994 and December 2000 with > or = 40% TBSA burns and at least 1 E&G procedure. Patients were grouped according to the day of their first operation. Patients allowed to heal indeterminate burns prior to excision and grafting of deep partial or full thickness burns were grouped as > or = d7 and were excluded from the present study. The authors correlated the time of first excision with infection, mortality and LOS. RESULTS: Seventy-five patients were identified and 12 patients allowed to heal indeterminate burn prior to excision and grafting of deep partial or full thickness burns were excluded. Sixty-three remaining patients included 51 males and 12 females. Mean burn size was 49% of total body surface area (TBSA) (44% deep partial or full thickness) and the mean age was 36 years. There were 61 flame (2 combined with electrical injuries), 1 scald and 1 chemical burn. Twelve died (19%) and 52 patients developed 121 infections. Whereas there was no statistical difference in mortality for patients operated on different days (p > 0.2), 60% of patients operated within the first 48 hours after injury died; this was not significant due to a small patient number CONCLUSIONS: The present data suggest that patients who undergo early excision and grafting within seven days following a major burn > or = 40% TBSA have equivalent infection or mortality rates regardless of when the first operation occurs between post burn day(PBD) 2 and PBD 7 (p > 0.2).

Adult↗

PubMed2006

Comparison of efficacy of 1% silver sulfadiazine and Acticoat for treatment of partial-thickness burn wounds.

BACKGROUND: Acticoat (Smith & Nephew, Hull, UK) is a silver-coated dressing reported to reduce infection and exhibit antimicrobial activity in wounds. OBJECTIVE: The purpose of the present study was to compare the efficacy ofacticoat and 1% silver sulfadiazine (1% AgSD) for treatment of partial thickness burn wounds. MATERIAL AND METHOD: The authors reviewed 50 patients who had partial thickness burn wounds less than 25% admitted to Siriraj Burn Unit from May 2002 to September 2005. All patients were divided into 2 groups: the acticoat treated group (25 patients) and the 1% silver sulfadiazine treated group (25 patients). The 2 groups were compared for the etiology of burn wound, demographic data including age, sex, % Total Body Surface Area burn (TBSA%), cultured organisms, wound infection and outcome of Length Of hospital Stay (LOS) and level of pain. RESULTS: The authors found no significant differences in age, TBSA (%) between both groups. 7 patients (28%) developed wound infection. There were no differences in wound infection and LOS between both groups (p > 0.05). All of the patients who developed wound infection responded well to targeted topical and systemic antibiotic treatment. The 1% AgSD treated group (6 of 25, 24%) obtained more split thickness skin graft to close the granulation defects compared to patients who were treated with acticoat (4 of 25, 16%) but no statistical significance, p = 0.32). Average pain scores in the acticoat treated groups were significantly lower than the 1% AgSD treated group (4 +/- 0.6 versus 5 +/- 0.7, respectively). CONCLUSION: The present study confirms the efficacy of acticoat treatment in partial thickness burn wound. The authors conclude that acticoat has an advantage of limiting the frequency of replacement of the dressing and provides a less painful alternative to wound care with 1% AgSD with comparable incidence of burn wound infection. This is due to its long wear time and the ease of application and removal.

Adult↗

PubMed2005

Changes in VEGF and nitric oxide after deep dermal injury in the female, red Duroc pig-further similarities between female, Duroc scar and human hypertrophic scar.

Despite decades of research, our understanding of human hypertrophic scar is limited. A reliable animal model could significantly increase our understanding. We previously confirmed similarities between scarring in the female, red, Duroc pig and human hypertrophic scarring. The purpose of this study was to: (1) measure vascular endothelial growth factor (VEGF) and nitric oxide (NO) levels in wounds on the female Duroc; and (2) to compare the NO levels to those reported for human hypertrophic scar. Shallow and deep wounds were created on four female Durocs. VEGF levels were measured using ELISA and NO levels with the Griess reagent. VEGF and NO levels were increased in deep wounds at 10 days when compared to shallow wounds (p < 0.05). At 15 weeks, VEGF and NO levels had returned to the level of shallow wounds. At 21 weeks, VEGF and NO levels had declined below baseline levels in deep wounds and the NO levels were significantly lower (p < 0.01). We found that VEGF and NO exhibit two distinctly different temporal patterns in shallow and deep wounds on the female Durocs. Furthermore, NO is decreased in female, Duroc scar as it is in human, hypertrophic scar further validating the usefulness of the model.

Animals↗

PubMed2005

Antioxidants inhibit fatty acid and glucose-mediated induction of neutral endopeptidase gene expression in human microvascular endothelial cells.

BACKGROUND: Neutral endopeptidase (NEP) is a membrane-bound metallopeptidase that degrades tachykinins and may regulate their role in wound repair. NEP enzyme activity is increased in diabetic wounds and skin compared with normal controls. We have shown that unsaturated fatty acids and glucose upregulate NEP activity in human microvascular endothelial cells (HMECs) and that vitamins E and C reduce this effect. STUDY DESIGN: To determine whether these changes involve NEP gene expression regulation, we analyzed NEP mRNA levels in HMECs cultured with elevated glucose (40 mM) and fatty acids oleate (40 microM) and linoleate (40 microM) for 48 hours or 1 month. Cells were exposed for an additional 48 hours to antioxidants vitamins E or C or N-acetylcysteine. Total RNA was extracted and analyzed for NEP mRNA using real-time reverse transcriptase polymerase chain reaction. NEP gene expression was standardized to beta-actin mRNA and results were analyzed using ANOVA. RESULTS: Elevated glucose, oleate, and linoleate upregulated NEP mRNA in short and longterm HMEC cultures, but did not alter rate of NEP mRNA degradation. Vitamins E and C and N-acetylcysteine blocked glucose- and fatty acid-induced NEP mRNA (p < or = 0.05). The potential role of oxidative stress in NEP activation was confirmed by demonstrating that elevated glucose and fatty acids increase H(2)O(2) levels in HMECs. CONCLUSIONS: Regulation of NEP enzyme activity by glucose and fatty acids appears to include gene expression transcription as well as modulation of enzyme activity. Our results also suggest that oxidative stress may be involved in upregulation of NEP by fatty acids and glucose.

Acetylcysteine↗

PubMed2004

Nerve quantification in female red Duroc pig (FRDP) scar compared to human hypertrophic scar.

A significant impediment to studying hypertrophic scar is the lack of an animal model. We have confirmed similarities between scarring in the female red Duroc pig (FRDP) and human hypertrophic scar and conclude that this model warrants validation. Reports have suggested that the cutaneous nervous system may play a role in hypertrophic scar development and several studies have shown nerve density in hypertrophic scar to be increased. The purpose of this study was to further validate the FRDP model of hypertrophic scar by quantifying nerves in FRDP tissue and comparing the findings to human hypertrophic scar. Wounds of varying depth were created on the backs of two FRDP and tissue samples were harvested at 10 days, 1 month and 5 months post-wounding. Human specimens were obtained from six burn patients. Immunohistochemistry was performed and digital images were captured. Color subtractive computer-assisted image analysis was used to quantify nerve density and nerve area fraction. The results demonstrate that nerve tissue is increased in FRDP scar tissue and is quite similar to that in human hypertrophic scar and to that described in the literature. These data provide additional evidence that the FRDP model may be useful for studying hypertrophic scarring.

Adolescent↗

PubMed2004

Further similarities between cutaneous scarring in the female, red Duroc pig and human hypertrophic scarring.

Knowledge of the pathophysiology of hypertrophic scarring following deep dermal injuries is minimal due to the lack of an animal model. We previously confirmed that thick scars in female, red Duroc pigs (FRDP) are similar to human hypertrophic scar. The purpose of this study was to evaluate TGFbeta1, IGF-1, decorin, and versican expression in FRDP wounds. Deep and shallow wounds on the backs of two FRDPs were studied over 5 months. Immunohistochemistry was performed for TGFbeta1, IGF-1, decorin, and versican. TGFbeta1 and IGF-1 mRNA were evaluated by in situ hybridization and RT-PCR. In shallow wounds (1) TGFbeta1 protein was not detectable and IGF-1 protein was seen at 10 days post-wounding. TGFbeta1 and IGF-1 mRNA were elevated for 30 days. (2) Decorin protein was not detected at 10th day, but returned to levels of uninjured skin. (3) Versican protein was not detectable at any time. In deep wounds, (1) TGFbeta1 and IGF-1 protein and mRNA were elevated early, (2) decorin protein was greatly reduced for the first 90 days, and (3) versican protein was present from 30 to 150 days. These findings correlate with findings reported in the literature for human hypertrophic scar and further validate the FRDP model of hypertrophic scarring.

Animals↗

PubMed2003

Fatty acids and glucose increase neutral endopeptidase activity in human microvascular endothelial cells.

Neutral endopeptidase (NEP), a membrane-bound metallopeptidase enzyme that degrades neuropeptides, bradykinin, atrial natriuretic factor, enkephalins, and endothelin may regulate response to injury. We have previously demonstrated increased NEP localization and enzyme activity in diabetic wounds and skin compared with normal controls. We hypothesized that hyperlipidemia and hyperglycemia associated with type 2 diabetes mellitus may induce excessive NEP activity and thereby diminish normal response to injury. Human microvascular endothelial cells were treated with five different fatty acids (40 microM) with varying degrees of saturation, including oleic acid, linoleic acid, palmitic acid, stearic acid, and linolenic acid and/or glucose (40 mM) for 48 h. The effect of the antioxidative agents vitamin E and C on NEP enzyme activation was determined by treating the cultured cells with alpha-tocopherol succinate and/or L-ascorbic acid. Cell membrane preparations were assayed for NEP activity by incubation with glutaryl-Ala-Ala-Phe-4-methoxy-beta naphthylamide to generate a fluorescent degradation product methoxy 2 naphthylamine. High glucose or fatty acid concentration upregulated NEP activity. The highest NEP activity was observed with combined elevated glucose, linoleic acid, and oleic acid (P < 0.05). Antioxidant vitamin E and C treatment significantly reduced NEP enzyme activity after fatty acid exposure (P < 0.05). Thus, hyperglycemia and hyperlipidemia associated with type 2 diabetes mellitus may increase endothelial cell NEP activity and thereby decrease early pro-inflammatory responses. The modulator effect of vitamin E and C on NEP membrane enzyme activity after exposure to fatty acid stimulation suggests that lipid oxidation may activate NEP.

Antioxidants↗

PubMedDate not supplied

Neutral endopeptidase inhibition in diabetic wound repair.

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 microM or 25 microM) 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/ microg) significantly exceeded activity in db/-skin (7.9 pmol MNA/hr/ microg; p = 0.02). In db/db mice, 25 microM 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.

Animals↗

PubMedDate not supplied

Social support correlates with survival in patients with massive burn injury.

Large burn size, inhalation injury, age, and associated trauma increase the rate of mortality after burns. However, not all patients with large burns and significant risk factors die. In this study, we wanted to determine other presenting factors that might indicate a survival benefit for burn patients with large burns. We reviewed charts of 36 patients with burns > or =60% TBSA that were aggressively resuscitated at the University of Washington Burn Center from 1990 to 2000 to determine whether survivors of large burns exhibit presenting variables that predict survival. Patients who had comfort care measures initiated at admission were excluded from this analysis. Survivors (n = 16) and nonsurvivors (n = 20) had no significant differences in age, total burn size, inhalation injury, or need for escharotomy. Full-thickness burn size was significantly smaller for survivors (58%) than for nonsurvivors (73%; P = .02). Survivors (81%) were more likely than nonsurvivors to have social support (35%; P = .007). A full-thickness burn > or =80 % TBSA was the only variable uniformly associated with mortality, suggesting that patients who survive large burns have a partial-thickness component that heals without surgery. The difference in degree of social support was one unique distinction that may impact patient survival and is worth further investigation.

Adolescent↗

PubMedDate not supplied

Nerve growth factor accelerates wound healing in diabetic mice.

Patients with diabetic neuropathy have reduced numbers of cutaneous nerves, which may contribute to an increased incidence of nonhealing wounds. Nerve growth factor (NGF) has been reported to augment wound closure. We hypothesized that topical 2.5S NGF, a biologically active subunit of the NGF polymer, would accelerate wound repair, augment nerve regeneration, and increase inflammation in excisional wounds in diabetic mice. A full-thickness 6-mm punch biopsy wound was created on the dorsum of C57BL/6J-m+ Leprdb mice (db/db) and heterozygous (db/-) littermates and treated daily with normal saline or 2.5S NGF (1 microg/day or 10 microg/day) on post-injury days 0-6. Time to closure, wound epithelialization, and degree of inflammation were compared using a Student's t-test. Color subtractive-computer-assisted image analysis was used to quantify immunolocalized nerves in wounds. Non-overlapping (20x) digital images of the wound were analyzed for nerve profile counts, area density (number of protein gene product 9.5 positive profiles per unit dermal area) and area fraction (protein gene product 9.5 positive area per unit dermal area). Healing times in db/db mice decreased from 30 days in normal saline-treated mice to 26 days in mice treated with 1 microg/day NGF (p<0.05) and 24 days in mice treated with 10 microg/day NGF (p<0.02). A similar trend in db/- mice was not significant. NGF treatment augmented epithelialization in the db/db mice (p<0.05). Histological evaluation of inflammation in healed wounds showed no statistical difference between treatment groups. Total nerve number, area density, and area fraction were increased in NGF-treated wounds at 14, 21, and 35 days (p<0.05). The 2.5 NGF subunit may improve wound closure kinetics by promoting epithelialization and nerve regeneration. Further studies to determine the role of nerves in wound repair are warranted.

Administration, Topical↗