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1.
Diabetes ; 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38869447

ABSTRACT

Macrophage (Mφ) plasticity is critical for normal wound repair; however, in type 2 diabetic wounds, Mφs persist in a low-grade inflammatory state that prevents the resolution of wound inflammation. Increased NLRP3 inflammasome activity has been shown in diabetic wound Mφs; however, the molecular mechanisms regulating NLRP3 expression and activity are unclear. Here, we identified that diabetic wound keratinocytes induce Nlrp3 gene expression in wound Mφs through IL-1 receptor-mediated signaling, resulting in enhanced inflammasome activation in the presence of PAMPs and DAMPs. We found that IL-1 alpha is increased in human and murine wound diabetic keratinocytes compared to non-diabetic controls and directly induces Mφ Nlrp3 expression through IL-1 receptor signaling. Mechanistically, we report that the histone demethylase, JMJD3, is increased in wound Mφs late post-injury and is induced by IL-1 alpha from diabetic wound keratinocytes, resulting in Nlrp3 transcriptional activation through an H3K27me3-mediated mechanism. Using genetically engineered mice deficient in JMJD3 in myeloid cells (Jmjd3fl/fllyz2cre+), we demonstrate that JMJD3 controls Mφ-mediated Nlrp3 expression during diabetic wound healing. Thus, our data suggest a role for keratinocyte-mediated IL-1 alpha/IL-1R signaling in driving enhanced NLRP3 inflammasome activity in wound Mφs. These data also highlight the importance of cell crosstalk in wound tissues and identify JMJD3 and the ILR signaling cascade as important upstream therapeutic targets for Mφ NLRP3 inflammasome hyperactivity in nonhealing diabetic wounds.

2.
Ann Surg ; 277(3): 416-422, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36745764

ABSTRACT

OBJECTIVE: To evaluate the prevalence of incivility among trainees and faculty in cardiothoracic surgery, general surgery, plastic surgery, and vascular surgery in the U.S, and to determine the association of incivility on job and work withdrawal and organizational commitment. BACKGROUND: Workplace incivility has not been described in surgery and can negatively impact the well-being of individuals, teams, and organizations at-large. METHODS: Using a cross-sectional, web-based survey study of trainees and faculty across 16 academic institutions in the U.S., we evaluated the prevalence of incivility and its association with work withdrawal and organizational commitment. RESULTS: There were 486 (18.3%) partial responses, and 367 (13.8%) complete responses from surgeons [including 183 (56.1%) faculty and 143 (43.9%) residents or fellows]. Of all respondents, 92.2% reported experiencing at least 1 form of incivility over the past year. Females reported significantly more incivility than males (2.4 ± 0.91 versus 2.05 ± 0.91, P < 0.001). Asian Americans reported more incivility than individuals of other races and ethnicities (2.43 ± 0.93, P = 0.003). After controlling for sex, position, race, and specialty, incivility was strongly associated with work withdrawal (ß = 0.504, 95% CI: 0.341-0.666). There was a significant interaction between incivility and organizational commitment, such that highly committed individuals had an even greater impact of incivility on the outcome of job and work withdrawal (ß = 0.178, 95% CI: 0.153-0.203). CONCLUSIONS: Incivility is widespread in academic surgery and is strongly associated with work withdrawal. Leaders must invest in strategies to eliminate incivility to ensure the well-being of all individuals, teams, and organizations at-large.


Subject(s)
Incivility , Surgeons , Male , Female , Humans , Cross-Sectional Studies , Faculty , Surveys and Questionnaires , Workplace , Organizational Culture
3.
Blood ; 141(7): 725-742, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36493338

ABSTRACT

Coronavirus-associated coagulopathy (CAC) is a morbid and lethal sequela of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. CAC results from a perturbed balance between coagulation and fibrinolysis and occurs in conjunction with exaggerated activation of monocytes/macrophages (MO/Mφs), and the mechanisms that collectively govern this phenotype seen in CAC remain unclear. Here, using experimental models that use the murine betacoronavirus MHVA59, a well-established model of SARS-CoV-2 infection, we identify that the histone methyltransferase mixed lineage leukemia 1 (MLL1/KMT2A) is an important regulator of MO/Mφ expression of procoagulant and profibrinolytic factors such as tissue factor (F3; TF), urokinase (PLAU), and urokinase receptor (PLAUR) (herein, "coagulopathy-related factors") in noninfected and infected cells. We show that MLL1 concurrently promotes the expression of the proinflammatory cytokines while suppressing the expression of interferon alfa (IFN-α), a well-known inducer of TF and PLAUR. Using in vitro models, we identify MLL1-dependent NF-κB/RelA-mediated transcription of these coagulation-related factors and identify a context-dependent, MLL1-independent role for RelA in the expression of these factors in vivo. As functional correlates for these findings, we demonstrate that the inflammatory, procoagulant, and profibrinolytic phenotypes seen in vivo after coronavirus infection were MLL1-dependent despite blunted Ifna induction in MO/Mφs. Finally, in an analysis of SARS-CoV-2 positive human samples, we identify differential upregulation of MLL1 and coagulopathy-related factor expression and activity in CD14+ MO/Mφs relative to noninfected and healthy controls. We also observed elevated plasma PLAU and TF activity in COVID-positive samples. Collectively, these findings highlight an important role for MO/Mφ MLL1 in promoting CAC and inflammation.


Subject(s)
COVID-19 , Histone-Lysine N-Methyltransferase , Animals , Humans , Mice , COVID-19/complications , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histones/metabolism , Inflammation/metabolism , Monocytes/metabolism , Myeloid-Lymphoid Leukemia Protein/genetics , Myeloid-Lymphoid Leukemia Protein/metabolism , SARS-CoV-2/metabolism , Urokinase-Type Plasminogen Activator/metabolism
4.
Cell Mol Immunol ; 19(11): 1251-1262, 2022 11.
Article in English | MEDLINE | ID: mdl-36127466

ABSTRACT

Macrophage plasticity is critical for normal tissue repair following injury. In pathologic states such as diabetes, macrophage plasticity is impaired, and macrophages remain in a persistent proinflammatory state; however, the reasons for this are unknown. Here, using single-cell RNA sequencing of human diabetic wounds, we identified increased JMJD3 in diabetic wound macrophages, resulting in increased inflammatory gene expression. Mechanistically, we report that in wound healing, JMJD3 directs early macrophage-mediated inflammation via JAK1,3/STAT3 signaling. However, in the diabetic state, we found that IL-6, a cytokine increased in diabetic wound tissue at later time points post-injury, regulates JMJD3 expression in diabetic wound macrophages via the JAK1,3/STAT3 pathway and that this late increase in JMJD3 induces NFκB-mediated inflammatory gene transcription in wound macrophages via an H3K27me3 mechanism. Interestingly, RNA sequencing of wound macrophages isolated from mice with JMJD3-deficient myeloid cells (Jmjd3f/fLyz2Cre+) identified that the STING gene (Tmem173) is regulated by JMJD3 in wound macrophages. STING limits inflammatory cytokine production by wound macrophages during healing. However, in diabetic mice, its role changes to limit wound repair and enhance inflammation. This finding is important since STING is associated with chronic inflammation, and we found STING to be elevated in human and murine diabetic wound macrophages at late time points. Finally, we demonstrate that macrophage-specific, nanoparticle inhibition of JMJD3 in diabetic wounds significantly improves diabetic wound repair by decreasing inflammatory cytokines and STING. Taken together, this work highlights the central role of JMJD3 in tissue repair and identifies cell-specific targeting as a viable therapeutic strategy for nonhealing diabetic wounds.


Subject(s)
Diabetes Mellitus, Experimental , Mice , Humans , Animals , Mice, Inbred C57BL , Macrophages/metabolism , Wound Healing , Inflammation/metabolism , Cytokines/metabolism
5.
JCI Insight ; 7(9)2022 05 09.
Article in English | MEDLINE | ID: mdl-35358091

ABSTRACT

Wound repair following acute injury requires a coordinated inflammatory response. Type I IFN signaling is important for regulating the inflammatory response after skin injury. IFN-κ, a type I IFN, has recently been found to drive skin inflammation in lupus and psoriasis; however, the role of IFN-κ in the context of normal or dysregulated wound healing is unclear. Here, we show that Ifnk expression is upregulated in keratinocytes early after injury and is essential for normal tissue repair. Under diabetic conditions, IFN-κ was decreased in wound keratinocytes, and early inflammation was impaired. Furthermore, we found that the histone methyltransferase mixed-lineage leukemia 1 (MLL1) is upregulated early following injury and regulates Ifnk expression in diabetic wound keratinocytes via an H3K4me3-mediated mechanism. Using a series of in vivo studies with a geneticall y engineered mouse model (Mll1fl/fl K14cre-) and human wound tissues from patients with T2D, we demonstrate that MLL1 controls wound keratinocyte-mediated Ifnk expression and that Mll1 expression is decreased in T2D keratinocytes. Importantly, we found the administration of IFN-κ early following injury improves diabetic tissue repair through increasing early inflammation, collagen deposition, and reepithelialization. These findings have significant implications for understanding the complex role type I IFNs play in keratinocytes in normal and diabetic wound healing. Additionally, they suggest that IFN may be a viable therapeutic target to improve diabetic wound repair.


Subject(s)
Diabetes Mellitus, Type 2 , Interferon Type I , Animals , Humans , Inflammation/metabolism , Mice , Wound Healing/physiology
6.
ACS Nano ; 16(2): 1999-2012, 2022 02 22.
Article in English | MEDLINE | ID: mdl-35107994

ABSTRACT

Macrophages are white blood cells with diverse functions contributing to a healthy immune response as well as the pathogenesis of cancer, osteoarthritis, atherosclerosis, and obesity. Due to their pleiotropic and dynamic nature, tools for imaging and tracking these cells at scales spanning the whole body down to microns could help to understand their role in disease states. Here we report fluorescent and radioisotopic quantum dots (QDs) for multimodal imaging of macrophage cells in vivo, ex vivo, and in situ. Macrophage specificity is imparted by click-conjugation to dextran, a biocompatible polysaccharide that natively targets these cell types. The emission spectral band of the crystalline semiconductor core was tuned to the near-infrared for optical imaging deep in tissue, and probes were covalently conjugated to radioactive iodine for nuclear imaging. The performance of these probes was compared with all-organic dextran probe analogues in terms of their capacity to target macrophages in visceral adipose tissue using in vivo positron emission tomography/computed tomography (PET/CT) imaging, in vivo fluorescence imaging, ex vivo fluorescence, post-mortem isotopic analyses, and optical microscopy. All probe classes exhibited equivalent physicochemical characteristics in aqueous solution and similar in vivo targeting specificity. However, dextran-mimetic QDs provided enhanced signal-to-noise ratio for improved optical quantification, long-term photostability, and resistance to chemical fixation. In addition, the vascular circulation time for the QD-based probes was extended 9-fold compared with dextran, likely due to differences in conformational flexibility. The enhanced photophysical and photochemical properties of dextran-mimetic QDs may accelerate applications in macrophage targeting, tracking, and imaging across broad resolution scales, particularly advancing capabilities in single-cell and single-molecule imaging and quantification.


Subject(s)
Quantum Dots , Thyroid Neoplasms , Dextrans , Humans , Iodine Radioisotopes , Macrophages , Optical Imaging , Positron Emission Tomography Computed Tomography , Quantum Dots/chemistry
8.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Article in English | MEDLINE | ID: mdl-34479991

ABSTRACT

COVID-19 induces a robust, extended inflammatory "cytokine storm" that contributes to an increased morbidity and mortality, particularly in patients with type 2 diabetes (T2D). Macrophages are a key innate immune cell population responsible for the cytokine storm that has been shown, in T2D, to promote excess inflammation in response to infection. Using peripheral monocytes and sera from human patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and a murine hepatitis coronavirus (MHV-A59) (an established murine model of SARS), we identified that coronavirus induces an increased Mφ-mediated inflammatory response due to a coronavirus-induced decrease in the histone methyltransferase, SETDB2. This decrease in SETDB2 upon coronavirus infection results in a decrease of the repressive trimethylation of histone 3 lysine 9 (H3K9me3) at NFkB binding sites on inflammatory gene promoters, effectively increasing inflammation. Mφs isolated from mice with a myeloid-specific deletion of SETDB2 displayed increased pathologic inflammation following coronavirus infection. Further, IFNß directly regulates SETDB2 in Mφs via JaK1/STAT3 signaling, as blockade of this pathway altered SETDB2 and the inflammatory response to coronavirus infection. Importantly, we also found that loss of SETDB2 mediates an increased inflammatory response in diabetic Mϕs in response to coronavirus infection. Treatment of coronavirus-infected diabetic Mφs with IFNß reversed the inflammatory cytokine production via up-regulation of SETDB2/H3K9me3 on inflammatory gene promoters. Together, these results describe a potential mechanism for the increased Mφ-mediated cytokine storm in patients with T2D in response to COVID-19 and suggest that therapeutic targeting of the IFNß/SETDB2 axis in T2D patients may decrease pathologic inflammation associated with COVID-19.


Subject(s)
Coronavirus/metabolism , Diabetes Mellitus, Type 2/metabolism , Histone-Lysine N-Methyltransferase/metabolism , Inflammation Mediators/metabolism , Inflammation/virology , Macrophages/metabolism , Animals , COVID-19/immunology , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Cytokine Release Syndrome , Cytokines/metabolism , Diabetes Mellitus, Type 2/genetics , Female , Histone-Lysine N-Methyltransferase/genetics , Humans , Inflammation/metabolism , Inflammation/physiopathology , Male , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , SARS-CoV-2/metabolism , Signal Transduction
9.
Acad Med ; 96(5): 655-660, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33208674

ABSTRACT

The COVID-19 pandemic has had significant ramifications for provider well-being. During these unprecedented and challenging times, one institution's Department of Surgery put in place several important initiatives for promoting the well-being of trainees as they were redeployed to provide care to COVID-19 patients. In this article, the authors describe these initiatives, which fall into 3 broad categories: redeploying faculty and trainees, ensuring provider safety, and promoting trainee wellness. The redeployment initiatives are the following: reframing the team mindset, creating a culture of grace and forgiveness, establishing a multidisciplinary wellness committee, promoting centralized leadership, providing clear communication, coordinating between departments and programs, implementing phased restructuring of the department's services, establishing scheduling flexibility and redundancy, adhering to training regulations, designating a trainee ombudsperson, assessing physical health risks for high-risk individuals, and planning for structured deimplementation. Initiatives specific to promoting provider safety are appointing a trainee safety advocate, guaranteeing personal protective equipment and relevant information about these materials, providing guidance regarding safe practices at home, and offering alternative housing options when necessary. Finally, the initiatives put in place to directly promote trainee wellness are establishing an environment of psychological safety, providing mental health resources, maintaining the educational missions, solidifying a sense of community by showing appreciation, being attentive to childcare, and using social media to promote community morale. The initiatives to carry out the department's strategy presented in this article, which were well received by both faculty and trainee members of the authors' community, may be employed in other departments and even outside the context of COVID-19. The authors hope that colleagues at other institutions and departments, independent of specialty, will find the initiatives described here helpful during, and perhaps after, the pandemic as they develop their own institution-specific strategies to promote trainee wellness.


Subject(s)
COVID-19/epidemiology , Internship and Residency , Occupational Stress/prevention & control , Pandemics , Personnel Administration, Hospital , Surgery Department, Hospital/organization & administration , COVID-19/transmission , Humans , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Leadership , Personal Protective Equipment , Personnel Staffing and Scheduling , SARS-CoV-2 , Social Support
10.
JCI Insight ; 5(17)2020 09 03.
Article in English | MEDLINE | ID: mdl-32879137

ABSTRACT

Macrophages are a primary immune cell involved in inflammation, and their cell plasticity allows for transition from an inflammatory to a reparative phenotype and is critical for normal tissue repair following injury. Evidence suggests that epigenetic alterations play a critical role in establishing macrophage phenotype and function during normal and pathologic wound repair. Here, we find in human and murine wound macrophages that cyclooxygenase 2/prostaglandin E2 (COX-2/PGE2) is elevated in diabetes and regulates downstream macrophage-mediated inflammation and host defense. Using single-cell RNA sequencing of human wound tissue, we identify increased NF-κB-mediated inflammation in diabetic wounds and show increased COX-2/PGE2 in diabetic macrophages. Further, we identify that COX-2/PGE2 production in wound macrophages requires epigenetic regulation of 2 key enzymes in the cytosolic phospholipase A2/COX-2/PGE2 (cPLA2/COX-2/PGE2) pathway. We demonstrate that TGF-ß-induced miRNA29b increases COX-2/PGE2 production via inhibition of DNA methyltransferase 3b-mediated hypermethylation of the Cox-2 promoter. Further, we find mixed-lineage leukemia 1 (MLL1) upregulates cPLA2 expression and drives COX-2/PGE2. Inhibition of the COX-2/PGE2 pathway genetically (Cox2fl/fl Lyz2Cre+) or with a macrophage-specific nanotherapy targeting COX-2 in tissue macrophages reverses the inflammatory macrophage phenotype and improves diabetic tissue repair. Our results indicate the epigenetically regulated PGE2 pathway controls wound macrophage function, and cell-targeted manipulation of this pathway is feasible to improve diabetic wound repair.


Subject(s)
Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus/physiopathology , Dinoprostone/pharmacology , Epigenesis, Genetic , Gene Expression Regulation/drug effects , Inflammation/prevention & control , Macrophages/drug effects , Wound Healing , Aged , Animals , Cyclooxygenase 2/metabolism , Humans , Inflammation/genetics , Inflammation/immunology , Inflammation/pathology , Macrophages/metabolism , Macrophages/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B/metabolism , Oxytocics/pharmacology , Phenotype , Pseudomonas aeruginosa/drug effects , Signal Transduction
11.
J Vasc Surg Venous Lymphat Disord ; 8(2): 299-305, 2020 03.
Article in English | MEDLINE | ID: mdl-32067731

ABSTRACT

OBJECTIVE: Venous thromboembolism (VTE) is a common disease with potentially devastating and long-term sequelae, such as pulmonary embolism and post-thrombotic syndrome (PTS). Given the mortality risk, prevalence of VTE, and limited access to diagnostic imaging, clinically relevant biomarkers for diagnosis and prognostication are needed. Therefore, this review aimed to summarize the data on clinically applicable biomarkers that best indicate acute VTE and chronic PTS. METHODS: We reviewed the medical and scientific literature from 2001 to 2019 for VTE biomarkers. Randomized controlled trials, meta-analyses, and review articles were included. Primary basic research papers with no clinical applicability, opinion papers, institutional guidelines, and case reports were excluded. RESULTS: We highlight the diagnostic value of D-dimer alongside other promising biomarkers, including cellular adhesion molecules, P-selectin, cytokines (interleukins 6 and 10), fibrin monomer complexes, and coagulation factors (factor VIII). CONCLUSIONS: High-sensitivity D-dimer remains the most clinically established VTE biomarker. Current research endeavors are under way to identify more precise biomarkers of VTE and PTS.


Subject(s)
Fibrin Fibrinogen Degradation Products/analysis , Inflammation Mediators/blood , Postthrombotic Syndrome/blood , Venous Thromboembolism/blood , Venous Thrombosis/blood , Animals , Biomarkers/blood , Humans , Postthrombotic Syndrome/diagnosis , Postthrombotic Syndrome/epidemiology , Predictive Value of Tests , Prognosis , Risk Factors , Venous Thromboembolism/diagnosis , Venous Thromboembolism/epidemiology , Venous Thrombosis/diagnosis , Venous Thrombosis/epidemiology
12.
Semin Vasc Surg ; 32(1-2): 23-26, 2019.
Article in English | MEDLINE | ID: mdl-31540652

ABSTRACT

Burnout among vascular surgery trainees is a significant problem and needs to be addressed at the level of the individual, training program duties, and at each institution. The clinical challenges and patient-oriented care required of a vascular surgeon generate a level of stress that requires its recognition and development of coping methods to promote well-being and personal happiness. There are ways to minimize burnout during surgical training, including acknowledgment of its symptoms, mentorship, self-care, and access to resources for stress reduction. Crucial factors in maintaining a positive outlook and a sense of meaningful work are faculty entrustability, receptive leadership, celebrating small victories, and recognition that resiliency is a skill that can be learned. Successful vascular surgeon training is a mission that requires everyone involved to actively promote well-being behavior and a supportive work environment. With appropriate implementation of these practices, our training programs can cultivate surgeons who are competent, compassionate, and committed to advancing vascular care.


Subject(s)
Adaptation, Psychological , Burnout, Professional/prevention & control , Education, Medical, Graduate/methods , Mental Health , Surgeons/education , Surgeons/psychology , Vascular Surgical Procedures/education , Burnout, Professional/etiology , Burnout, Professional/psychology , Curriculum , Humans , Interpersonal Relations , Leadership , Mentors , Resilience, Psychological , Workplace/psychology
13.
J Vasc Surg Venous Lymphat Disord ; 7(3): 452-462, 2019 May.
Article in English | MEDLINE | ID: mdl-30853559

ABSTRACT

BACKGROUND: Deep venous thrombosis (DVT) in the pediatric population is rare, occurring in about 10 to 14 out of 10,000 pediatric admissions annually, but with serious consequences such as pulmonary embolism and/or post-thrombotic syndrome. There is a dearth of surgical literature regarding this entity, its pathophysiology, its treatment and its long-term sequelae. METHODS: An extensive search of available surgical and medical literature in Medline, PubMed was obtained by searching terms synonymous with pediatric DVT. Case reports and opinion articles were excluded. Ongoing clinical trials were culled from clinicaltrial.gov by searching for pediatric DVT studies. Institutional guidelines, where available, were included in this summary. RESULTS: We provide a clinically relevant summary with the aims of improving prevention, early identification and treatment of pediatric DVT. CONCLUSIONS: Although rare and frequently with subtle presentations, pediatric DVT can be serious. Early identification and treatment can be instrumental in limiting sequelae and in improving outcomes for these patients.


Subject(s)
Venous Thrombosis , Adolescent , Age of Onset , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Predictive Value of Tests , Risk Factors , Treatment Outcome , Venous Thrombosis/diagnostic imaging , Venous Thrombosis/epidemiology , Venous Thrombosis/physiopathology , Venous Thrombosis/therapy
14.
J Vasc Surg ; 69(2): 532-543, 2019 02.
Article in English | MEDLINE | ID: mdl-30683200

ABSTRACT

BACKGROUND: Groin wound infections represent a substantial source of patients' morbidity and resource utilization. Definitions and reporting times of groin infections are poorly standardized, which limits our understanding of the true scope of the problem and potentially leads to event under-reporting. Our objective was to investigate the timing and variation of groin wound complications after vascular surgery. METHODS: We reviewed all patients who underwent vascular surgery with a groin incision at our institution during 2013 (N = 256; 32% female; mean age, 68.8 years). We analyzed patient- and procedure-level variables. Our primary outcome was any groin complication within 180 days. We classified groin-related events as major (hospital readmission or reoperation for groin wound) or minor (wound opened in clinic, initiation of antibiotics specifically for a groin wound, or new groin hematoma or wound drainage). RESULTS: The Kaplan-Meier estimated rate of groin complications at 180 days was 23% (n = 53/256); 29 (54%) were major and 24 (46%) were minor. The Kaplan-Meier 30-day event rate was 13% for any complication and only 3% for major complications, indicating that most events occurring within the first 30 days did not require readmission or reoperation. By 180 days, the overall complication rate rose to 23% and the major event rate to 14%, indicating that nearly all complications occurring after 30 days required readmission or reoperation. Those with a groin complication more commonly had tissue loss (23% vs 12%; P = .05), underwent infrainguinal bypass (42% vs 22%; P=.004), had a redo incision (32% vs 18%; P = .03), and had a longer operation (77% vs 65% surgery >200 minutes; P = .07). There were no significant differences in patients' comorbidities, skin closure, dressing type, prosthetic implants, hemostatic agents, or discharge status. CONCLUSIONS: Whereas >20% of patients suffered a groin complication, nearly half of these events occurred after 30 days. Standardized reporting measures limited to 30-day events or infection definitions that are limited to the need for antibiotic use may misrepresent the true infection rate and thus highlight the need for uniform reporting standards.


Subject(s)
Groin/blood supply , Hematoma/etiology , Quality Indicators, Health Care/standards , Research Design/standards , Surgical Wound Infection/etiology , Vascular Surgical Procedures/adverse effects , Aged , Aged, 80 and over , Anti-Bacterial Agents , Data Accuracy , Databases, Factual , Drainage , Female , Hematoma/diagnosis , Hematoma/therapy , Humans , Male , Middle Aged , Patient Readmission , Reoperation , Retrospective Studies , Surgical Wound Infection/diagnosis , Surgical Wound Infection/therapy , Time Factors , Treatment Outcome
15.
J Vasc Surg Venous Lymphat Disord ; 5(2): 257-260, 2017 03.
Article in English | MEDLINE | ID: mdl-28214495

ABSTRACT

Aneurysmal disease of the internal iliac vein is rare, with no standard indication for or accepted modality of treatment. Here we report an instance of unilateral, primary left internal iliac venous aneurysm and associated pelvic venous insufficiency. Following extensive workup for alternative causes, the aneurysm and left gonadal vein were coil embolized with good effect.


Subject(s)
Iliac Aneurysm/etiology , Venous Insufficiency/complications , Embolization, Therapeutic/methods , Humans , Iliac Aneurysm/diagnostic imaging , Iliac Aneurysm/therapy , Male , Middle Aged , Pelvis/blood supply , Phlebography , Venous Insufficiency/diagnostic imaging , Venous Insufficiency/therapy
16.
Biochemistry ; 53(43): 6776-85, 2014 Nov 04.
Article in English | MEDLINE | ID: mdl-25286246

ABSTRACT

NEMO is a scaffolding protein that, together with the catalytic subunits IKKα and IKKß, plays an essential role in the formation of the IKK complex and in the activation of the canonical NF-κB pathway. Rational drug design targeting the IKK-binding site on NEMO would benefit from structural insight, but to date, the determination of the structure of unliganded NEMO has been hindered by protein size and conformational heterogeneity. Here we show how the utilization of a homodimeric coiled-coil adaptor sequence stabilizes the minimal IKK-binding domain NEMO(44-111) and furthers our understanding of the structural requirements for IKK binding. The engineered constructs incorporating the coiled coil at the N-terminus, C-terminus, or both ends of NEMO(44-111) present high thermal stability and cooperative melting and, most importantly, restore IKKß binding affinity. We examined the consequences of structural content and stability by circular dichoism and nuclear magnetic resonance (NMR) and measured the binding affinity of each construct for IKKß(701-745) in a fluorescence anisotropy binding assay, allowing us to correlate structural characteristics and stability to binding affinity. Our results provide a method for engineering short stable NEMO constructs to be suitable for structural characterization by NMR or X-ray crystallography. Meanwhile, the rescuing of the binding affinity implies that a preordered IKK-binding region of NEMO is compatible with IKK binding, and the conformational heterogeneity observed in NEMO(44-111) may be an artifact of the truncation.


Subject(s)
I-kappa B Kinase/chemistry , Protein Engineering , Binding Sites , Crystallography, X-Ray , Humans , I-kappa B Kinase/genetics , Magnetic Resonance Spectroscopy , Protein Binding , Protein Stability , Protein Structure, Tertiary
17.
Proteins ; 82(7): 1370-5, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24375686

ABSTRACT

We designed and characterized a soluble mimic of the parathyroid hormone (PTH) receptor (PTH1R) that incorporates the N-terminus and third extracellular loop of PTH1R, important for ligand binding. The engineered receptor (PTH1R-NE3) was conceived to enable easy production and the use of standard biochemical and biophysical assays for the screening of competitive antagonists of PTH. We show that PTH1R-NE3 is folded, thermodynamically stable and selectively binds PTH. We also demonstrate the utility of our mimic by identifying a small molecule that competes with PTH in our PTH1R-NE3-based fluorescence polarization assay. Antagonists to PTH1R, a transmembrane protein belonging to the class B G-protein coupled receptor family, may provide new therapeutic options for calcium metabolism diseases like humoral hypercalcemia of malignancy.


Subject(s)
Protein Engineering/methods , Receptor, Parathyroid Hormone, Type 1/chemistry , Recombinant Fusion Proteins/chemistry , Humans , Models, Molecular , Nuclear Magnetic Resonance, Biomolecular , Receptor, Parathyroid Hormone, Type 1/genetics , Receptor, Parathyroid Hormone, Type 1/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Solubility
18.
J Pept Sci ; 19(8): 504-10, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23794508

ABSTRACT

The parathyroid hormone, PTH, is responsible for calcium and phosphate ion homeostasis in the body. The first 34 amino acids of the peptide maintain the biological activity of the hormone and is currently marketed for calcium imbalance disorders. Although several methods for the production of recombinant PTH(1-34) have been reported, most involve the use of cleavage conditions that result in a modified peptide or unfavorable side products. Herein, we detail the recombinant production of (15) N-enriched human parathyroid hormone, (15) N PTH(1-34), generated via a plasmid vector that gives reasonable yield, low-cost protease cleavage (leaving the native N-terminal serine in its amino form), and purification by affinity and size exclusion chromatography. We characterize the product by multidimensional, heteronuclear NMR, circular dichroism, and LC/MS.


Subject(s)
Endopeptidases/chemistry , Parathyroid Hormone/biosynthesis , Amino Acid Sequence , Base Sequence , Chromatography, Affinity , Escherichia coli , Humans , Molecular Sequence Data , Parathyroid Hormone/chemistry , Parathyroid Hormone/isolation & purification , Protein Structure, Secondary , Proteolysis , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification
19.
Biochemistry ; 51(41): 8092-9, 2012 Oct 16.
Article in English | MEDLINE | ID: mdl-23002929

ABSTRACT

The BK polyoma virus is a leading cause of chronic post kidney transplantation rejection. One target for therapeutic intervention is the initial association of the BK virus with the host cell. We hypothesize that the rate of BKV infection can be curbed by competitively preventing viral binding to cells. The X-ray structures of homologous viruses complexed with N-terminal glycoproteins suggest that the BC and HI loops of the viral coat are determinant for binding and thereby infection of the host cell. The large size of the viral coat precludes it from common biophysical and small molecule screening studies. Hence, we sought to develop a smaller protein template incorporating the identified binding loops of the BK viral coat in a manner that adequately mimics the binding characteristics of the BK virus coat protein to cells. Such a mimic may serve as a tool for the identification of inhibitors of BK viral progression. Herein, we report the design and characterization of a reduced-size and soluble template derived from a four-helix protein-TM1526 of Thermatoga maritima archaea bacteria-which maintains the topological display of the BC and HI loops as found in the viral coat protein, VP1, of BKV. We demonstrate that the GT1b and GD1b sialogangliosides, which bind to the VP1 of BKV, also associate with our BKV template. Employing a GFP-tagged template, we show host cell association that is dose dependent and that can be reduced by neuraminidase treatment. These data demonstrate that the BKV template mimics the host cell binding observed for the wild-type virus coat protein VP1.


Subject(s)
BK Virus/pathogenicity , Capsid Proteins/metabolism , Kidney Diseases/virology , Molecular Mimicry , Amino Acid Sequence , Animals , BK Virus/metabolism , Capsid Proteins/chemistry , Chlorocebus aethiops , Flow Cytometry , Models, Molecular , Molecular Sequence Data , Nuclear Magnetic Resonance, Biomolecular , Vero Cells , X-Ray Diffraction
20.
J Comb Chem ; 11(1): 34-43, 2009.
Article in English | MEDLINE | ID: mdl-19105723

ABSTRACT

For the successful implementation of Distributed Drug Discovery (D(3)) (outlined in the accompanying Perspective), students, in the course of their educational laboratories, must be able to reproducibly make new, high quality, molecules with potential for biological activity. This article reports the successful achievement of this goal. Using previously rehearsed alkylating agents, students in a second semester organic chemistry laboratory performed a solid-phase combinatorial chemistry experiment in which they made 38 new analogs of the most potent member of a class of antimelanoma compounds. All compounds were made in duplicate, purified by silica gel chromatography, and characterized by NMR and LC/MS. As a continuing part of the Distributed Drug Discovery program, a virtual D(3) catalog based on this work was then enumerated and is made freely available to the global scientific community.


Subject(s)
Antineoplastic Agents/chemical synthesis , Biomedical Research/education , Drug Discovery/methods , Melanoma/drug therapy , Laboratories , Universities
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