Browsing by Subject "Infections"

Now showing 1 - 6 of 6
  • Thumbnail Image
    Item
    1735. The Pig Skin Commensal D. incerta Exhibits Antimicrobial Activity Against Methicillin-Resistant Staphylococcus aureus
    (Oxford University Press, 2022) Wei, Monica; Knight, Simon; Flowers, Laurice; Walsh, Jasmine; Grice, Elizabeth A.; Medicine, School of Medicine
    Background: Methicillin-resistant Staphylococcus aureus (MRSA) infections occur commonly on skin and cause significant healthcare burden. MRSA can also stably colonize the skin and nasal passages, contributing to community spread. This colonization results in long-term interaction with the skin microbiome, which harbors a diverse community of bacteria that often use antimicrobial molecules to compete for ecologic niches. We hypothesize that the skin microbiome contains bacteria that secrete novel antimicrobial agents against MRSA. Methods: Pigs are an established model organism for skin whose microbiome is not well explored. We mined the pig skin microbiome for bacterial species that inhibited MRSA via a modified disc diffusion assay. Results: We find that the novel pig skin commensal D. incerta inhibits USA300 strain MRSA via a secreted antimicrobial protein that can be isolated from cell-free supernatant. Analysis of the D. incerta genome shows little homology to known antimicrobial genes clusters. The identity of the antimicrobial molecule and whether its antimicrobial activity persists in the context of MRSA skin infection remain unclear. We characterize the identity of this antimicrobial molecule via parallel genomic and biochemical approaches. Finally, we propose to test the ability of D. incerta to impede MRSA colonization and improve healing of MRSA-mediated skin infection, two clinically important skin conditions. Conclusion: We screened the pig skin microbiome and successfully identified bacterial inhibitors of MRSA. Preliminary data suggest that the pig skin commensal D. incerta secretes a novel antimicrobial protein. Our current efforts focus on identifying this antimicrobial molecule and investigating its therapeutic potential in animal models of skin.
  • Thumbnail Image
    Item
    177. Prophylactic Absorbable Antibiotic Beads For High Risk Implant-based Reconstruction: A Single Institution Pilot Study
    (Wolters Kluwer, 2023-05-19) Ahmed, Shahnur; Lee, Jason T. C.; Roth, Dylan D.; Liu, Steven; Fisher, Carla S.; Fan, Betty; Imeokparia, Folasade; Ludwig, Kandice; Lester, Mary E.; Hassanein, Aladdin H.; Surgery, School of Medicine
    PURPOSE: Infections are problematic in implant-based reconstruction after mastectomies. Infection rates have been reported to be as high as 31%. Strategies to reduce the risk of infection include various antibiotic irrigation solutions, “no-touch” techniques, optimizing sterility, and empiric antibiotic use for skin flora coverage. Absorbable antibiotic beads have been well described for other indications, including orthopedic and pressure sore reconstruction. The purpose of this study is to evaluate the use of prophylactic biodegradable antibiotic beads during pre-pectoral and sub-pectoral implant-based breast reconstruction following mastectomy. METHODS: A single-center retrospective review of patients who underwent implant-based breast reconstruction post-mastectomy between 2019 to 2022. Patients were divided into two groups: Group I were deemed “high risk” by the senior author and received biodegradable antibiotic beads (1 gram vancomycin, 240 mg gentamicin) during tissue expander or implant reconstruction (pre-pectoral or subpectoral) while Group II (control) had no antibiotic beads. Demographic data, diabetes, body mass index (BMI), implant plane (pre-pectoral or sub-pectoral), smoking and use of mesh were recorded. Outcome variables included postoperative cellulitis or infection requiring oral or intravenous antibiotics and tissue expander loss at 90 days. RESULTS: In our study period, 19 patients (36 total implants/expanders) received biodegradable antibiotic beads during implant-based breast reconstruction (Group I). There were 174 patients (290 total expanders) who did not receive antibiotic beads (Group II). Patients in Group I had a history of previous expander/implant infection in 73.6%. Pre-pectoral placement of implants occurred in 84.2% of patients in Group I and 74.1% in Group II. Diabetes was prevalent in 15.8% of Group I compared to 5.7% seen in Group II patients. The mean BMI in Group I was 30.5 kg/m2 compared to 27.8 kg/m2 in Group II (p-value 0.88). Implant infection rate of Group I at 90 days was 8.3% (3/36 total expanders) compared to 8.6% (25/290 total expanders) in Group II. Implant loss in Group I was 5.5% (2/26 total expanders) compared to 7.6% (22/290) in Group II. CONCLUSION: The incidence of infection in high risk patients who have absorbable antibiotic beads placed during the time of reconstruction appears to be normalized to the control group in this pilot study, suggesting that absorbable antibiotic beads may decrease postoperative infection complications. Future studies may further clarify its benefit in selected groups.
  • Thumbnail Image
    Item
    A phenomenological study of the lived experience of nurses in the battle of COVID-19
    (Springer Nature, 2021) Gunawan, Joko; Aungsuroch, Yupin; Marzilli, Colleen; Fisher, Mary L.; Nazliansyah; Sukarna, Ade; School of Nursing
    Background: Roles and responsibilities of nurses are crucial in the battle of Coronavirus disease 2019 (COVID-19), but nursing duties also put them at risk for infections. Purpose: The purpose of this study was to explore the lived experience of nurses in combatting COVID-19 in Belitung, Indonesia. Methods: This study employed a phenomenological study design. Online interviews and chatting were conducted among 17 clinical nurses who were purposively selected from March to June 2020. Data were audio-recorded, transcribed, and validated among researchers. The thematic approach was used for data analysis. Findings: Seven themes emerged (1) feeling "nano-nano", (2) lack of N95 masks, (3) we are just pawns, (4) being rejected, (5) please do not spread our identity, (6) we miss home, and (7) feeling betrayed by regulation. Discussion: Findings of this study should be used by government agencies, nurses, and the general population in combatting COVID-19.
  • Thumbnail Image
    Item
    Autophagy modulates CD4+ T-cell lineage recommitment upon pathogen infection
    (Springer Nature, 2020-07) Yang, Kai; Chi, Hongbo; Pediatrics, School of Medicine
  • Thumbnail Image
    Item
    Daily Situational Brief, February 9, 2015
    (MESH Coalition, 2/9/2015) MESH Coalition
  • Thumbnail Image
    Item
    Immunomodulatory Effects of Oxylipin 10-HOME Produced by Biofilm Results in Host-Biofilm Interaction in Breast Implant Illness
    (Wolters Kluwer, 2022) Khan Mohammed, Imran; Minto, Robert; Kelley-Patteson, Christine; Timsina, Lava; Singh, Kanhaiya; Van Natta, Bruce W.; Mohan, Ganesh; Chauhan, Ruvi; Lester, Mary; Hassanein, Al; Gordillo, Gayle M.; Sen, Chandan; Kadin, Marshall; Sinha, Mithun; Surgery, School of Medicine
    PURPOSE: The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings. Nearly 300,000 women annually have breast implant surgery in the United States, for reasons including post-mastectomy breast reconstruction, revision of prior augmentation/ reconstruction, cosmetic augmentation, and gender affirmation. There has been increased identification of patients experiencing a constellation of symptoms related to their implants termed as breast implant illness (BII). In this work, we report that bacterial biofilm associated with breast implant, metabolize fatty acid oleic acid present in the breast tissue milieu to oxylipins, one such oxylipin identified from this study is (E)-10-hydroxy-8-octadecenoic acid (10-HOME). We hypothesize that immunomodulatory effects of oxylipin 10-HOME produced by biofilm present on the implant could be a possible etiology for BII pathogenesis. METHOD: Implants, peri-prosthetic tissues and blood was collected from BII subjects (n=46) and two control groups, group I, (non-BII, n=34) patients with breast implants, no BII symptoms. Group II (normal tissue, n = 20), patients without an implant, whose breast tissue was removed due to surgical procedures. A questionnaire developed based on epidemiological studies on BII screened for the commonly reported symptoms associated with BII. Predictive variables included age, diabetes status, co-morbidities, type (smooth/textured) and duration of implant. Scanning electron microscopy (SEM), 16S rRNA (genomic) next generation sequencing (NGS) were used for bacterial biofilm identification. 10-HOME was quantitated through targeted and untargeted lipidomic analyses using LC-MS-MS. RNA-Seq analysis was performed on peri-prosthetic breast tissues. Flow cytometry and mass cytometry (CyToF) were conducted to investigate the role of immune cells. RESULTS: Bacterial biofilm was detected through SEM and 16SrRNA NGS. Bivariate analysis using cross-tabulation was performed between presence of biofilm and the study groups. Using the two-sample test of proportions with z-tests, Staphylococcus epidermidis colonization was observed to be higher in the BII group (73.33%) compared to non-BII group (16.67%, p=0.018) and the normal group (10%, p=0.036). The BII group was 2.4 times more likely to have S. epidermidis colonization compared to the non-BII group (Odds Ratio=2.4). Similarly, when comparing with normal group, the BII group was 3.4 times more likely to have S. epidermidis. Elevated levels of 10-HOME in BII compared to non-BII samples, (p<0.0001) were observed through mass spectrometry. Positive correlation was observed between bacterial abundance and concentration of 10-HOME in BII subjects (R2=0.88). RNA-Seq analysis on peri-prosthetic tissue and flow/ mass cytometry analyses from peripheral blood derived lymphocytes showed increased abundance of CD4+ Th1 cells. Th1 cells have been reported to be activated in auto-immune diseases. No significant difference was observed in the abundance of other Th subtypes (Th2, Th9 and Th22). Oxylipin 10-HOME polarized CD4+ naïve T cells to Th1 subtype in vitro. CONCLUSION: This study investigated the biofilm hypothesis of BII through a biofilm derived immunogenic metabolite. Through a systematic cause-effect based studies, the work shows activation of Th1 cells in presence of 10-HOME. The study provides the first evidence of a possible etiology of BII mediated via bacterial biofilm derived 10-HOME.