Ascending aorta thoracic endovascular aortic repair for infected pseudoaneurysm.

A 70-year-old woman with a bioprosthetic aortic valve replacement for aortic valve endocarditis complicated by recurrent endocarditis and requiring homograft aortic root replacement 10 years earlier had presented at 1 month after her admission for pseudomonal bacteremia with right-sided chest pain. An aortic pseudoaneurysm, identified on computed tomography, was treated with an ascending aorta thoracic endovascular aortic repair using two overlapping abdominal aortic stent grafts in the ascending aorta. Postoperative and follow-up imaging demonstrated exclusion of the pseudoaneurysm with stable positioning of the stent grafts. Ascending aorta thoracic endovascular aortic repair can be performed safely with good short-term results in patients presenting with infected pseudoaneurysms of the ascending aorta.

Endovascular repair of traumatic axillosubclavian artery injuries.

Gun violence reached a 20-year peak in 2020, with the first-line treatment of axillosubclavian vascular injuries (SAVIs) remaining unknown. Traditional open exposure is difficult and exposes patients to iatrogenic venous and brachial plexus injury. The practice of endovascular treatment has been increasing. We performed a retrospective analysis of SAVIs at a level I trauma center. Seven patients were identified. Endovascular repair was performed in five patients. Technical success was 100%. The early results suggest that endovascular treatment of trauma-related SAVIs can be performed safely and effectively. However, complications such as stent thrombosis or occlusion can occur, demonstrating the need for surveillance.

Retrograde Superior Mesenteric Artery Stenting in Case of SMA Shuttering.

This case describes a patient who underwent endovascular repair for an extent V thoracoabdominal aneurysm with planned coverage of the celiac artery. Following deployment of the stent graft, the superior mesenteric artery was shuttered, and the patient subsequently developed signs and symptoms of bowel ischemia. The patient underwent successful retrograde open superior mesenteric artery stenting with resolution of her symptoms. Although retrograde open mesenteric artery stenting (ROMS) has been primarily shown to be effective in acute mesenteric ischemia, this case demonstrates that ROMS can be used as a salvage option for shuttering during endovascular procedures.

The anti-scarring effect of corneal stromal stem cell therapy is mediated by transforming growth factor ß3.

BACKGROUND: Corneal stromal stem cells (CSSC) reduce corneal inflammation, prevent fibrotic scarring, and regenerate transparent stromal tissue in injured corneas. These effects rely on factors produced by CSSC to block the fibrotic gene expression. This study investigated the mechanism of the scar-free regeneration effect. METHODS: Primary human CSSC (hCSSC) from donor corneal rims were cultivated to passage 3 and co-cultured with mouse macrophage RAW264.7 cells induced to M1 pro-inflammatory phenotype by treatment with interferon-γ and lipopolysaccharides, or to M2 anti-inflammatory phenotype by interleukin-4, in a Transwell system. The time-course expression of human transforming growth factor ß3 (hTGFß3) and hTGFß1 were examined by immunofluorescence and qPCR. TGFß3 knockdown for > 70% in hCSSC [hCSSC-TGFß3(si)] was achieved by small interfering RNA transfection. Naïve CSSC and hCSSC-TGFß3(si) were transplanted in a fibrin gel to mouse corneas, respectively, after wounding by stromal ablation. Corneal clarity and the expression of mouse inflammatory and fibrosis genes were examined. RESULTS: hTGFß3 was upregulated by hCSSC when co-cultured with RAW cells under M1 condition. Transplantation of hCSSC to wounded mouse corneas showed significant upregulation of hTGFß3 at days 1 and 3 post-injury, along with the reduced expression of mouse inflammatory genes (CD80, C-X-C motif chemokine ligand 5, lipocalin 2, plasminogen activator urokinase receptor, pro-platelet basic protein, and secreted phosphoprotein 1). By day 14, hCSSC treatment significantly reduced the expression of fibrotic and scar tissue genes (fibronectin, hyaluronan synthase 2, Secreted protein acidic and cysteine rich, tenascin C, collagen 3a1 and α-smooth muscle actin), and the injured corneas remained clear. However, hCSSC-TGFß3(si) lost these anti-inflammatory and anti-scarring functions, and the wounded corneas showed intense scarring. CONCLUSION: This study has demonstrated that the corneal regenerative effect of hCSSC is mediated by TGFß3, inducing a scar-free tissue response.

Efficacy of an Enhanced Recovery After Surgery (ERAS) Pathway in Elderly Patients Undergoing Spine and Peripheral Nerve Surgery.

OBJECTIVE: Elderly patients are a vulnerable patient population in elective spinal surgery. Older patients have more medical comorbidities and are also more sensitive to opiate medications. Despite this, spine and peripheral nerve surgery is still feasible in these patients, and an Enhanced Recovery After Surgery (ERAS) regimen can further enhance the safety profile. METHODS: This is a before and after cohort study at a single institution on elderly patients who underwent elective spine and peripheral nerve surgery. Patients were prospectively enrolled in a novel ERAS protocol from April 2017 to December 2018. The control group was a historical cohort of patients who underwent surgery from September 2016 to December 2016. The primary outcome was self-reported opioid use at 1- and 3-months postoperatively. The secondary outcome was compliance with the ERAS protocol across several measures including patient-controlled (PCA) use, patient-reported pain scores, mobilization and ambulation status, and Foley catheter use. RESULTS: Among 504 patients aged 65 and older compared to historic controls there was a significant reduction in the use of post-operative opioids at one month (36.2% vs. 71.7%, p < 0.001) and 3 months after surgery (33.0% vs. 80.0%, p < 0.001). 504 consecutive elderly patients were included in the ERAS protocol compared to a control group of 60. The two groups had similar surgical procedures and baseline demographics, with similar mean ages (ERAS 73.2 years vs. control 73.5 years, p = 0.67). The ERAS group showed improved mobilization and ambulation on POD 0 in compliance with our protocol compared to the control group (mobilization: 60.0% vs. 10.0%, p < 0.001; ambulation: 36.1% vs. 10.0%, p < 0.001), with no inpatient falls reported for either group. CONCLUSIONS: ERAS facilitates reduction in opiate use at 1- and 3-month intervals postoperatively in patients greater than 65 years old undergoing elective spine and peripheral nerve surgery. Early mobilization and ambulation are safe and feasible in this population.

Mesenchymal Stem Cells Reduce Corneal Fibrosis and Inflammation via Extracellular Vesicle-Mediated Delivery of miRNA.

Mesenchymal stem cells from corneal stromal stem cells (CSSC) prevent fibrotic scarring and stimulate regeneration of transparent stromal tissue after corneal wounding in mice. These effects rely on the ability of CSSC to block neutrophil infiltration into the damaged cornea. The current study investigated the hypothesis that tissue regeneration by CSSC is mediated by secreted extracellular vesicles (EVs). CSSC produced EVs 130-150 nm in diameter with surface proteins that include CD63, CD81, and CD9. EVs from CSSC reduced visual scarring in murine corneal wounds as effectively as did live cells, but EVs from human embryonic kidney (HEK)293T cells had no regenerative properties. CSSC EV treatment of wounds decreased expression of fibrotic genes Col3a1 and Acta2, blocked neutrophil infiltration, and restored normal tissue morphology. CSSC EVs labeled with carboxyfluorescein succinimidyl ester dye, rapidly fused with corneal epithelial and stromal cells in culture, transferring microRNA (miRNA) to the target cells. Knockdown of mRNA for Alix, a component of the endosomal sorting complex required for transport, using siRNA, resulted in an 85% reduction of miRNA in the secreted EVs. The EVs with reduced miRNA were ineffective at blocking corneal scarring. Furthermore, CSSC with reduced Alix expression also lost their regenerative function, suggesting EVs as an obligate component in the delivery of miRNA. The results of these studies support an essential role for extracellular vesicles in the process by which CSSC cells block scarring and initiate regeneration of transparent corneal tissue after wounding. EVs appear to serve as a delivery vehicle for miRNA, which affects the regenerative action. Stem Cells Translational Medicine 2019;8:1192-1201.

Development of a Manikin-Based Performance Evaluation Method for Loose-Fitting Powered Air-Purifying Respirators.

OBJECTIVE: Loose-fitting powered air-purifying respirators (PAPRs) are increasingly being used in healthcare. NIOSH has previously used advanced manikin headforms to develop methods to evaluate filtering facepiece respirator fit; research has now begun to develop methods to evaluate PAPR performance using headforms. This preliminary study investigated the performance of PAPRs at different work rates to support development of a manikin-based test method. METHODS: Manikin penetration factors (mPF) of three models of loose-fitting PAPRs were measured at four different work rates (REST: 11 Lpm, LOW: 25 Lpm, MODERATE: 48 Lpm, and HIGH: 88 Lpm) using a medium-sized NIOSH static advanced headform mounted onto a torso. In-mask differential pressure was monitored throughout each test. Two condensation particle counters were used to measure the sodium chloride aerosol concentrations in the test chamber and also inside the PAPR facepiece over a 2-minute sample period. Two test system configurations were evaluated for returning air to the headform in the exhalation cycle (filtered and unfiltered). Geometric mean (GM) and 5th percentile mPFs for each model/work rate combination were computed. Analysis of variance tests were used to assess the variables affecting mPF. RESULTS: PAPR model, work rate, and test configuration significantly affected PAPR performance. PAPR airflow rates for the three models were approximately 185, 210, and 235 Lpm. All models achieved GM mPFs and 5th percentile mPFs greater than their designated Occupational Safety and Health Administration assigned protection factors despite negative minimum pressures observed for some work rate/model combinations. CONCLUSIONS: PAPR model, work rate, and test configuration affect PAPR performance. Advanced headforms have potential for assessing PAPR performance once test methods can be matured. A manikin-based inward leakage test method for PAPRs can be further developed using the knowledge gained from this study. Future studies should vary PAPR airflow rate to better understand the effects on performance. Additional future research is needed to evaluate the correlation of PAPR performance using advanced headforms to the performance measured with human subjects.

Structure and Glycan Binding of a New Cyanovirin-N Homolog.

The HIV-1 envelope glycoprotein gp120 is heavily glycosylated and bears numerous high mannose sugars. These sugars can serve as targets for HIV-inactivating compounds, such as antibodies and lectins, which bind to the glycans and interfere with viral entry into the target cell. We determined the 1.6 Å x-ray structure of Cyt-CVNH, a recently identified lectin from the cyanobacterium Cyanothece(7424), and elucidated its glycan specificity by NMR. The Cyt-CVNH structure and glycan recognition profile are similar to those of other CVNH proteins, with each domain specifically binding to Manα(1-2)Manα units on the D1 and D3 arms of high mannose glycans. However, in contrast to CV-N, no cross-linking and precipitation of the cross-linked species in solution was observed upon Man-9 binding, allowing, for the first time, investigation of the interaction of Man-9 with a member of the CVNH family by NMR. HIV assays showed that Cyt-CVNH is able to inhibit HIV-1 with ∼4-fold higher potency than CV-N(P51G), a stabilized version of wild type CV-N. Therefore, Cyt-CVNH may qualify as a valuable lectin for potential microbicidal use.