708. Evaluation of Fungal Culture versus Bacterial Culture for the Identification of Various Mold Species

Background Invasive mold infections are challenging to diagnose and in part relies on fungal cultures. A large proportion of mold isolates are recovered on routine bacterial cultures in our medical center, thus we sought to define the utility of bacterial versus fungal cultures for isolation of mold from clinical specimens. Methods Routine bacterial and fungal culture results from wound, tissue, body fluid, and respiratory specimens from Jan 2019-Dec 2020 from Keck Medical Center of USC (Los Angeles, CA) were retrospectively reviewed. Cases were excluded if specimens were collected specifically for dermatophyte recovery or for blood culture. Cultures in which mold, including dimorphic fungi, were isolated were included in the evaluation. Results Mold was isolated from 612 specimens from 408 patients, with recovery from 329 bacterial and 450 fungal cultures. Among the 329 bacterial cultures, fungal cultures were not requested in 119 (36.2%) while the remaining 210 had concurrent fungal cultures which recovered mold in 167 cases (79.5%). Of 450 fungal cultures recovering mold, a corresponding bacterial culture was performed in 445, isolating mold in 181 (38.8%) of these cases. Two or more molds were found in 28 fungal cultures and in 5 bacterial cultures. Of positive specimens with both fungal and bacterial cultures performed (n=488), mold was isolated in fungal cultures in 446 (91.4%) and in bacterial cultures in 209 (42.9%) (Table). Yield of molds in 488 specimens with concomitant bacterial and fungal cultures Conclusion Although a significant number of molds are recovered in routine bacterial cultures, over half would be missed without concomitant fungal cultures. Conversely, recovery of clinically relevant mold species was optimal when both bacterial and fungal cultures were requested on a specimen. This may be related to increased specimen sampling and incubation conditions allowing for broader organism recovery. Disclosures All Authors: No reported disclosures

Zones of cellular damage around pulsed-laser wounds

After a tissue is wounded, cells surrounding the wound adopt distinct wound-healing behaviors to repair the tissue. Considerable effort has been spent on understanding the signaling pathways that regulate immune and tissue-resident cells as they respond to wounds, but these signals must ultimately originate from the physical damage inflicted by the wound. Tissue wounds comprise several types of cellular damage, and recent work indicates that different types of cellular damage initiate different types of signaling. Hence to understand wound signaling, it is important to identify and localize the types of wound-induced cellular damage. Laser ablation is widely used by researchers to create reproducible, aseptic wounds in a tissue that can be live-imaged. Because laser wounding involves a combination of photochemical, photothermal and photomechanical mechanisms, each with distinct spatial dependencies, cells around a pulsed-laser wound will experience a gradient of damage. Here we exploit this gradient to create a map of wound-induced cellular damage. Using genetically-encoded fluorescent proteins, we monitor damaged cellular and sub-cellular components of epithelial cells in living Drosophila pupae in the seconds to minutes following wounding. We hypothesized that the regions of damage would be predictably arrayed around wounds of varying sizes, and subsequent analysis found that all damage radii are linearly related over a 3-fold range of wound size. Thus, around laser wounds, the distinct regions of damage can be estimated after measuring any one. This report identifies several different types of cellular damage within a wounded epithelial tissue in a living animal. By quantitatively mapping the size and placement of these different types of damage, we set the foundation for tracing wound-induced signaling back to the damage that initiates it.

Screening of Surfactants for Improved Delivery of Antimicrobials and Poly-Lactic-co-Glycolic Acid Particles in Wound Tissue

Topical wound management is often a challenge due to the poor penetration of antimicrobials in wound tissue and across the biofilm matrix where bacteria are embedded. Surfactants have been used for decades to improve the stability of formulations, increase drug solubility, and enhance penetration. In this study, we screened different detergents with respect to their cytotoxicity and their ability to improve the penetration of poly-lactic-co-glycolic acid (PLGA) particles in wound tissue. Among the tested surfactants, Kolliphor SLS and Tween 80 increased the penetration of PLGA particles and had a limited cytotoxicity. Then, these surfactants were used to formulate PLGA particles loaded with the poorly water-soluble antibiotic ciprofloxacin. The antimicrobial efficacy of the formulations was tested in a wound infection model based on human ex vivo skin. We found that even though PLGA particles had the same antimicrobial efficiency than the particle-free drug formulation, thanks to their solubilizing and anti-biofilm properties, the surfactants remarkably improved the antimicrobial activity of ciprofloxacin with respect to the drug formulation in water. We conclude that the use of Tween 80 in antimicrobial formulations might be a safe and efficient option to improve the topical antimicrobial management of chronic wound infections.

Effect of Zaoxiu ointment on wound-healing in experimental second degree burns rats

Purpose: To evaluate the healing efficacy of a Traditional Chinese Medicine (TCM) preparation Zaoxiu Burn Ointment (ZBO) on experimental burns in rats. Methods: The rats were randomly divided into four groups of eight rats each: control group, silver sulfadiazine (SSD)-treated group, moist exposed burn ointment (MEBO)-treated group and ZBO-treated group. ZBO, SSD and MEBO were applied topically twice daily for 7 days. SSD and MEBO were used as reference control. The observation of wound area contraction and histological analysis of wound tissues were performed. The effect of ZBO on MMPs, VEGF and Type-III collagen proteins of wound tissue in rats were determined by Western blot. Results: After 10 days of topical treatment with ZBO, ZBO-treated group showed faster reduction in wound area in comparison with control groups (p < 0.01). MMP-2, MMP-9, VEGF and type-III collagen expression of the wound tissue increased significantly (p < 0.05) in comparison with the control burn wounds in rats. The ZBO had no cytotoxic effect on BHK-21 cell line. Histological results showed an overall early recovery and regeneration in ZBO-treated group when compared with control group. Conclusion: ZBO possesses significant wound-healing activity in full-thickness burn wounds in rats, and can potentially be developed for the treatment of burns patient in future.

Wound-healing effect of Platycodon grandiflorus (Jacq.) extract in rats

Purpose: To evaluate the healing effect of Platycodon grandiflorus (Jacq.). extract (PGE) on experimental burn wounds in rats. Methods: Rats were randomly divided into four groups of eight rats each: control group, silver sulfadiazine (SSD)-treated group, moist exposed burn ointment (MEBO)-treated group and PGE-treated group. PGE, SSD and MEBO were applied topically twice daily for 7 days. SSD and MEBO were used as reference control. External observation of wound area contraction and histological analysis of wound tissues was performed respectively. The effect of PGE on matrix metalloproteases (MMPs), vascular endothelial growth factor (VEGF) and Type-III Collagen proteins of wound tissue in rats were analysed by Western blot. Results: After 10 days of topical treatment with PGE, PGE-treated group showed faster reduction in wound area when compared with control groups (p < 0.01). Matrix metalloprotease-2 (MMP-2), matrix metalloprotease-9 (MMP-9), VEGF and type-III collagen expressions in the wound tissue increased significantly (p < 0.05) when compared with the control burn wounds. Histological results showed an overall early recovery and regeneration in PGE-treated group when compared with control group. Conclusion: PGE possesses a significant wound-healing activity in full-thickness burn wounds in rats. Therefore, it can potentially be developed for the management of burns.

Wound Management Property of a Hydroethanolic Leaf Extract of Cnestis ferruginea DC

Context. Nature assumes imperative part in managing both acute and chronic ailments. Cnestis ferruginea is one of the sources of healing prowlers in traditional medicine practice for the treatment of wounds. Nonetheless, there are no scientific reports archived so far on the wound management activity of this plant. Objective. To establish the wound management property of a hydroethanolic Cnestis ferruginea leaf extract (CFHE). Materials and Methods. The wound area was measured after excision at the dorsal part of the Albino rats, and after treatment with 5–15% w / w CFHE ointments for 14 days. Absorbances of platelet-rich plasma treated with 0.8–100 mg/mL CFHE and an aggregating agent were spectrophotometrically determined in an in vitro platelet aggregation test. Wound tissue histopathology of CFHE ointment-treated animals revealed angiogenesis, reepithelialization, deposition of collagen, and granular tissue formation in wound tissues. Reduction in thigh oedema and pain threshold, in 7-day-old chicks, were assessed by carrageenan-induced oedema and Randall-Sellito pressure models, respectively. By the Agar diffusion method, bacterial growth inhibition by a 15% w / w CFHE ointment was investigated on Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus. Aureus, and Streptococcus pyogenes. Results. All concentrations of CFHE ointment significantly reduced ( p < 0.0001 ) wound area by 29–41% posttreatment. CFHE (1.6–100 mg/ml) promoted platelet aggregation ( p ≤ 0.0001 ) by 37–67% (IC50: 3.1–6.2 mg/ml). There were improved wound tissue reepithelization, fibroblast proliferation, angiogenesis, and collagen deposition with 15% CFHE ointment treatment. CFHE ointment significantly ( p ≤ 0.0001 ) and dose-dependently reduced thigh oedema and showed a significant ( p ≤ 0.05 ) analgesic effect. In vitro, 15% CFHE ointment caused >100% growth inhibition of selected bacteria. Conclusion. The hydroethanolic leaf extract of Cnestis ferruginea possesses wound healing, platelet aggregation, anti-inflammatory, analgesic, and antimicrobial properties and, hence, could be effective in the management of open and some closed wounds.

Cold Atmospheric Plasma Promotes the Immunoreactivity of Granulocytes In Vitro

Cold atmospheric plasma (CAP) reduces bacteria and interacts with tissues and cells, thus improving wound healing. The CAP-related induction of neutrophils was recently described in stained sections of wound tissue in mice. Consequently, this study aimed to examine the functionality of human polymorphonuclear cells (PMN)/granulocytes through either a plasma-treated solution (PTS) or the direct CAP treatment with different plasma modes and treatment durations. PTS analysis yielded mode-dependent differences in the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) after CAP treatment. Live-cell imaging did not show any chemo-attractive or NETosis-inducing effect on PMNs treated with PTS. The time to maximum ROS production (TmaxROS) in PMNs was reduced by PTS and direct CAP treatment. PMNs directly treated with CAP showed an altered cell migration dependent on the treatment duration as well as decreased TmaxROS without inducing apoptosis. Additionally, flow cytometry showed enhanced integrin and selectin expression, as a marker of activation, on PMN surfaces. In conclusion, the modification of PMN immunoreactivity may be a main supporting mechanism for CAP-induced improvement in wound healing.

Enhanced Skin Incisional Wound Healing With Intracellular ATP Delivery via Macrophage Proliferation and Direct Collagen Production

This study sought to use a newly developed intracellular ATP delivery to enhance incisional wound healing to reduce surgical wound dehiscence and to explore possible mechanism for this effect. Thirty-five adult New Zealand white rabbits were used. Skin incisions were made on the back and closed. ATP-vesicles were mixed with a neutral cream for one side of the wounds while the neutral cream alone was used on the other side of the wounds. Laser speckle contrast imaging (LSCI), biomechanical, histological, and immunohistochemical analyses were performed 7 and 14 days after surgery, and macrophage culture was used to test the enhanced collagen production ability. Among them, 10 were used for wound perfusion study and 25 were used for wound biomechanical and histological/immunohistochemical studies. Wound tissue perfusion was reduced after surgery especially in early days. Wound tissue tensile strength, breaking stress, and elasticity were all much higher in the ATP-vesicle treated group than in the cream treated group at days 7 and 14. The healing was complemented by earlier macrophage accumulation, in situ proliferation, followed by direct collagen production. The results were further confirmed by human macrophage culture. It was concluded that intracellular ATP delivery enhanced healing strength of incisional wounds via multiple mechanisms.