Subdermal Skin Research Articles

Comparison of genomic DNA sequencing to anerobic cultures to detect efficacy of hydrogen peroxide at reducing cutibacterium acnes bacterial burden during primary shoulder arthroplasty

BackgroundThe purpose of this investigation is to compare Cutibacterium acnes diagnosis using culturing vs. genomic DNA sequencing (NextGen) at various timepoints and locations during primary total shoulder arthroplasty. Additionally, we intend to compare the effects of hydrogen peroxide on standard culture technique results with genomic DNA sequencing. MethodsA prospective diagnostic study of 40 patients undergoing primary total shoulder arthroplasty was performed. Intraoperatively, 4 tissue samples were collected per patient: subdermal skin edge following initial skin incision, subdermal skin edge following hydrogen peroxide soak for 5 minutes, glenohumeral joint capsule, and subdermal skin edge prior to wound closure. Each tissue specimen was collected twice (one for culture analysis and the other for genomic (NextGen) DNA sequencing analysis) for a total of 8 specimens per patient and 320 tissue specimens in total. All anaerobic cultures were held for 14 days. Each culture plate was divided into quadrants and the amount of growth was quantified. Tissue samples were collected for genomic sequencing DNA analysis. Genomic sequencing results provided relative percentage of bacteria for each specimen detected. ResultsThere were 18/40 males (45%) and no postoperative complications. Average age was 72.2 ± 11.8. Overall, 18% (29/160) of standard anaerobic cultures were positive for C. Acnes and 26% (942/160) were positive with genomic (Nextgen) DNA sequencing. When comparing the NextGen results with anaerobic standard cultures, there was a calculated negative predictive value of 85.6% and positive predictive value of 28.6%. Sensitivity of the NextGen was 41.4% and specificity was 77.1%. Bacterial culture rates did not significantly change from the beginning to the end of surgery as demonstrated on standard culturing and the NextGen analysis (P > .05). After treatment with hydrogen peroxide, the standard culturing technique showed no significant difference between the samples; however, there was a significant increase in bacterial burden (12.4%) noted with NextGen analysis (P = .0147). ConclusionNextGen culturing is a novel technique to help identify shoulder prosthetic joint infections. These results show that, NextGen is better at identifying the absence of infection, but has a high false positive rate indicative of its ability to identify contaminants as compared to standard anaerobic culturing methods. The increase in bacterial burden after peroxide treatment noted with NextGen could also be secondary to the test’s increased ability to identify both living and dead bacterial pathogens.

Evaluation of Wound Healing Following Wide Surgical Resection and Subdermal Skin Flap Reconstruction for Management of Soft Tissue Tumours in 20 Dogs

Background: Tumours in dogs are increasing day by day and the mainstay of treatment is surgery. Wide surgical resection of soft tissue tumour in dogs is mandatory to prevent recurrence but it leads to the formation of a large skin defect requiring skin reconstruction. Among the various skin reconstruction techniques, subdermal skin flap is a simple reconstruction technique which can be performed by harvesting full-thickness skin from the surrounding skin without using special instruments. The current study was aimed to evaluate the healing and recurrence of tumours in dogs after wide surgical resection of tumour and subdermal skin flap reconstruction.Methods: 20 dogs with soft tissue tumours presented to MSVH, GADVASU, Ludhiana, Punjab, during the period 2019-2020 were treated by wide surgical resection and subdermal skin flap technique. Routine clinico-physical, Hematobiochemical, Radiographic examinations, Fine Needle Aspiration Cytology, Histopathology and Culture Sensitivity Test were performed. Different types of flap were created according to the location of tumour and availability of the loose skin and wound healing was evaluated and complications recorded. Result: Healing of subdermal flap was seen in 15 dogs (75%) while necrosis of subdermal flap was recorded in 5 dogs (25 %) of the cases of which 4 of them had mobility of flap base and were located in ventral abdomen (n=4) and limb (n=1). Overall tumour recurrence was recorded in 3 dogs (15%) which were located in limbs of which 2 dogs had lung metastasis and the tumours were malignant. It can be concluded that single pedicle advancement flaps for thoracic region; bipedicle advancement flap for thoracic and abdominal regions; rotational flaps for lateral thoracic region and transposition flap for proximal limb region are feasible skin reconstruction techniques for the repair of large skin defects in dogs.

Detection of subclinical skin manifestation in patients with psoriasis and psoriatic arthritis by fluorescence optical imaging

ObjectivesTo investigate the frequency of subclinical skin inflammation in both hands by fluorescence optical imaging (FOI) in patients with psoriasis/psoriatic arthritis (Pso/PsA) vs. rheumatoid arthritis (RA) and healthy individuals, and to correlate these findings with cardiovascular (CV) risk factors.Patients and methodsThe FOI scans were analyzed retrospectively to detect clinically invisible skin enhancement (0–3 scale) in both hands without relationship to underlying joints or blood vessels. We further characterized the FOI patterns and sorted the scans into groups based on the assumed diagnosis (Pso/PsA, RA, and healthy controls), which was compared with the physician’s diagnosis. Furthermore, the associations between CV risk factors and imaging findings were investigated by regression analyses.ResultsWe included FOI scans of patients with Pso/PsA (n = 80), RA (n = 78), and healthy controls (n = 25). Subclinical skin enhancement on the back of their hands was more common in Pso/PsA (72.5%) than in RA patients (20.5%) and healthy individuals (28.0%) (p < 0.001). Based on the FOI pattern, the majority of patients with Pso/PsA (72.5%), RA (76.9%), and healthy controls (68.0%) were classified correctly using the physician-based diagnosis as reference (overall agreement of 74%, kappa = 0.57). No CV risk factors except body weight (kg) were associated with subclinical skin enhancement (OR 1.04, 95% CI 1.02–1.06; p < 0.001).ConclusionSubclinical subdermal skin inflammation was common in Pso/PsA patients using FOI. Based on the FOI pattern, most patients with Pso/PsA and were classified with the correct diagnosis. We demonstrated an important influence of the body weight on our FOI results. FOI may be a helpful novel tool to study microcirculation in rheumatic diseases with skin involvement.

Plasmodium falciparum Gametocyte Density and Infectivity in Peripheral Blood and Skin Tissue of Naturally Infected Parasite Carriers in Burkina Faso.

Background Plasmodium falciparum transmission depends on mature gametocytes that can be ingested by mosquitoes taking a blood meal on human skin. Although gametocyte skin sequestration has long been hypothesized as important contributor to efficient malaria transmission, this has never been formally tested.MethodsIn naturally infected gametocyte carriers from Burkina Faso, we assessed infectivity to mosquitoes by direct skin feeding and membrane feeding. We directly quantified male and female gametocytes and asexual parasites in finger-prick and venous blood samples, skin biopsy samples, and in of mosquitoes that fed on venous blood or directly on skin. Gametocytes were visualized in skin tissue with confocal microscopy.ResultsAlthough more mosquitoes became infected when feeding directly on skin then when feeding on venous blood (odds ratio, 2.01; 95% confidence interval, 1.21–3.33; P = .007), concentrations of gametocytes were not higher in the subdermal skin vasculature than in other blood compartments; only sparse gametocytes were observed in skin tissue.DiscussionOur data strongly suggest that there is no significant skin sequestration of P. falciparum gametocytes. Gametocyte densities in peripheral blood are thus informative for predicting onward transmission potential to mosquitoes and can be used to target and monitor malaria elimination initiatives.

Thermistor-controlled subdermal skin tightening for the aging face: Clinical outcomes and efficacy.

ObjectivePatients are increasingly seeking nonsurgical treatment for the aging face. The purpose of this study was to evaluate the clinical efficacy and outcomes of a thermistor‐controlled subdermal skin tightening device (ThermiTight) as a treatment modality for the aging face.MethodsA retrospective analysis of 12 patients was completed on patients having undergone ThermiTight for midface and neck skin tightening. Only five patients had a greater than 1 year follow‐up and were included in the study. Two blinded reviewers assessed photographs taken pre‐procedure and 1 year post‐procedure using a standardized skin laxity scale. Patient charts were reviewed to assess for complications up to 12 months post‐treatment.ResultsThe mean age of included patients was 57 years, and all five patients were female. One (20%) patient treated with ThermiTight was also treated with injectables (Botox, Juvéderm) simultaneously. One (20%) patient developed a wound complication. One (20%) patient complained of incisional site pain at her first postoperative visit that subsequently self‐resolved. On a five‐point scale to assess facial skin laxity, there was an average improved score of 0.85 per patient (P < .001) at one year post‐procedure. Two blinded reviewers correctly categorized photographs as either being “baseline” or “post‐procedure” 100% of the time. There was no significant difference between the skin laxity scores by the blinded reviewers (P = .05).ConclusionThermiTight is a new technology used for nonsurgical treatment of the aging face. Long‐term outcomes demonstrate the safety and efficacy of the procedure. Complications are rare, but possible, in the use of ThermiTight. Level of Evidence: 3

Application of liquid platelet-rich fibrin for treating hyaluronic acid-related complications: A case report with 2 years of follow-up

Platelet-rich fibrin (PRF) is a blood concentrate system derived from the peripheral blood by means of centrifugation. In esthetic medicine, hyaluronic acid (HA) is safe and most frequently used for esthetic treatment and skin augmentation. However, some complications such as inflammation were reported in the literature after the injection of HA as a xenogeneic material. The present case report presents a case of the treatment of complication after HA injection. The subject received the injection of HA in combination with filler material and developed a purulent and granulomatous dermal and subdermal skin infection that was eliminated by incision. To prevent scar formation, the subject was treated with dermal and subdermal liquid PRF injections for 1 year, and the case was documented for 2 years. The PRF injections promoted wound healing and minimized the scar formation. After two sessions, the patient swelling and redness were significantly decreased compared to baseline. After 4 sessions, complete wound healing was achieved without obvious scar formation. This case report shows that the use of liquid PRF as a bioactive system promotes wound healing and skin regeneration as well as minimizes scar formation. However, controlled clinical studies are needed to further elucidate the benefit of PRF as an autologous and bioactive material for esthetic skin treatment.

In situ foamable, degradable polyurethane as biomaterial for soft tissue repair

Degradable foams which can be inserted endoscopically as liquid or pasty mixtures into soft tissue defects possess a promising potential for the surgical treatment of such defects. The defects can be sealed under in situ foaming and simultaneous material expansion. We developed an in situ foamable (l-lactide-co-ε-caprolactone)-based, star-shaped prepolymer by ring opening polymerization of l-lactide and ε-caprolactone in the presence of meso-erythritol as starter. By conversion of the terminal hydroxyl groups of the formed oligoester with lysine diisocyanate ethyl ester (LDI) an isocyanate-endcapped, reactive prepolymer has been received. Foaming can be initiated by addition of 1,4-diazabicyclo[2,2,2]octane (DABCO), water, LDI and DMSO. By varying the composition of these additives, the foaming and curing time could be varied within a clinically acceptable range. A porosity of approximately 90%, and an average tensile strength of 0.3MPa with elongations of 90% were determined for the foams.In vitro cytotoxicity on cured foams was assayed on 3T3 fibroblasts and demonstrated an excellent cytocompatibility. This was also confirmed in an in vivo study using an established rat model, where prefabricated foams and in situ hardening material were inserted into subdermal skin incisions in parallel. The feature of chronic inflammation was only weakly developed in both groups and slightly more pronounced and persisted for longer time in the group of in situ foamed material. In both groups the foreign materials were vascularized, degraded and substituted by connective tissue. The results encourage to proceed with trials where the materials are used to fill more heavily loaded defects.

The Effect of Using a Delayed-Absorbable Subdermal Skin Closure on Postoperative Wound Complications in Obese Women Undergoing Abdominal Gynecologic Surgery [46

INTRODUCTION: Wound complications in obese patients can use considerable resources in their care. Although closure of the subcutaneous layers has shown to help, these problems still occur. We hypothesized that the addition of subdermal closure using a delayed-absorbable suture to standard wound-closure techniques in obese patients might further reduce wound problems. METHODS: A chart review of laparotomies with midline vertical skin incision performed for gynecologic disorders during the previous 3 years was conducted. In addition to demographic data, data on wound separation, use of antibiotics, readmission for wound care, referral to the wound care center, and use of wound vacuum dressings were abstracted. Separate χ2 or Fisher exact tests were used as appropriate. RESULTS: We identified 106 patients; 36 received standard closure plus subdermal closure using a delayed-absorbable suture (case group) and 70 received standard closure (control group). Body mass index (calculated as weight (kg)/[height (m)]2), age, and comorbidities were similar among the groups. Wound separation was noted in 10 patients (four in the case group, six in the control group). Antibiotics were used in one patient (in the control group). Three patients were referred to the wound care center (one in the case group, two in the control group) and three patients were readmitted to the hospital for wound care (all from the control group). Wound vacuum dressings were used in two patients (both in the control group). No difference in postoperative visits was noted between groups. CONCLUSION: A tendency toward fewer wound complications was seen in the group receiving subdermal closure using a delayed-absorbable suture. Owing to the rarity of these complications and the exploratory nature of our study, no statistical significance was noted for the variables studied between groups. A larger prospective clinical trial is needed.

Cutaneous bacterial species from Lithobates catesbeianus can inhibit pathogenic dermatophytes.

Antibiotics are being successfully used to fight many infectious diseases caused by pathogenic microorganisms. However, new infectious diseases are continuously being identified, and some known pathogens are becoming resistant against known antibiotics. Furthermore, many antifungals are causing serious side effects in long-term treatments of patients, and many skin infections caused by dermatophytes are difficult to cure. The beneficial roles of resident cutaneous microbiota to inhibit pathogenic microorganisms have been shown for many vertebrate species. Microbial symbionts on the amphibian skin for example can be a source of powerful antimicrobial metabolites that can protect amphibians against diseases, such as chytridiomycosis, caused by a fungal pathogen. In this research, we investigated whether cutaneous bacterial species isolated from Lithobates catesbeianus (North American bullfrog), an invasive amphibian species that is resistant to chytridiomycosis, produce secondary metabolites that can be used to inhibit the growth of three species of dermatophytes (Microsporum gypseum, Epidermophyton floccosum, and Trichophyton mentagrophytes) which are known to cause topical or subdermal skin infections in humans. Strongly anti-dermatophyte bacterial species that belonged to the Bacillaceae, Streptomycetaceae, Pseudomonadaceae, Xanthomonadaceae, Aeromonadaceae, and Enterobacteriaceae were identified. This research has provided evidence of the presence of cutaneous anti-dermatophyte bacteria from L. catesbeianus which might provide a basis for health care providers to experiment with new antifungals in the future.

A New Approach for Adipose Tissue Treatment and Body Contouring Using Radiofrequency-Assisted Liposuction

A new liposuction technology for adipocyte lipolysis and uniform three-dimensional tissue heating and contraction is presented. The technology is based on bipolar radiofrequency energy applied to the subcutaneous adipose tissue and subdermal skin surface. Preliminary clinical results, thermal monitoring, and histologic biopsies of the treated tissue demonstrate rapid preaspiration liquefaction of adipose tissue, coagulation of subcutaneous blood vessels, and uniform sustained heating of tissue.

Hypothermia induction and recovery in free-ranging rats

1. To avoid anesthesia confounders, free-ranging rats were exposed (4 h) to cool water (CW; 10 °C; 5 cm), warm water (WW; 35 °C; 5 cm) or temperate air (TA; 25 °C) to induce hypothermia, or control for water or novel environment stress, respectively. 2. While WW and TA core temperature ( T c) and the brown adipose tissue ( T BAT)/subdermal skin ( T SDS) temperature relationship remained similar, CW hypothermia induction was variable (34.5–26.1 °C; 9–240 min) and associated with tachycardia (517.8±4.7 bpm) greater than WW (386.5±5.5 bpm) or TA (372.2±7.7 bpm) with CW T BAT (36.5±0.03 °C) elevated above CW T SDS (35.9±0.05 °C). 3. Without anesthesia to blunt thermoregulatory countermeasures to hypothermia, variable resistance to T c depression, tachycardia rather than bradycardia and BAT thermogenic responses were demonstrated.

Ectopic transplantation of equine invasive trophoblast.

A system for transplanting invasive equine trophoblast (i.e., chorionic girdle) to ectopic sites has been developed as a means to study the differentiation of this tissue and to assess maternal immune responses to the conceptus tissue in a site outside the uterus. Chorionic girdle was isolated from Day 33 to 34 conceptuses and surgically placed into the vulvar mucosa or subdermal skin of recipient mares. Biopsy specimens of the graft sites for immunohistochemical staining were taken at weekly or biweekly intervals after grafting. Serum samples were collected from each recipient and tested for antibody to donor major histocompatibility complex (MHC) class I antigens using the lymphocyte microcytotoxicity assay. Transplanted trophoblast cells expressed differentiation markers associated with invading chorionic girdle and endometrial cup cells. The transplanted trophoblast cells were also labeled by an antibody to eCG. Strong cellular and humoral immune responses to the transplanted tissue were mounted by the recipients, similar to those occurring during normal equine pregnancy. Despite these responses, the invasive trophoblast transplants survived for at least 28 days after grafting and downregulated MHC class I antigens, as do the mature endometrial cup cells in equine pregnancy. These findings suggest that invasive equine trophoblast has the capacity to differentiate fully in equine nonuterine tissues, and that it can evade maternal immune responses independent of the physiological state of pregnancy and in sites other than the uterus.