This study evaluated safety and image quality of MRI exams performed for patients with traumatic knee dislocations in knee-spanning stabilization devices. It is an IRB-approved retrospective design ...with waived informed consent that included 63 patients with traumatic knee dislocation. 56 patients had metallic external fixators, and 7 patients had non-metallic knee immobilizers. 7 patients had bilateral dislocations yielding a total of 70 knee MRIs. 1.5 Tesla MRI exams were performed for all patients who were awake and alert at the time of imaging. All knee-spanning external fixators were considered “MR conditional” by the FDA. The electronic medical record was reviewed for notes from the technologist and nursing staff documenting any patient complaints or adverse events during the MRI exam as required by departmental protocol. Qualitative analysis of the six most frequently performed sequences were independently conducted by 2 musculoskeletal radiologists using a 5-point Likert scale. Overall image quality and select time intervals between the two groups were compared using an independent sample t test and the Mann-Whitney U test, respectively. No adverse events were reported for a 40-minute average estimated patient scan time with the stabilization devices in the MR gantry. Mean values of Likert scale scores were generated from two readers' data for comparison between the external fixation and the immobilizer groups. Most knee MRI exams with external fixators were within diagnostic quality despite artifacts (grade 3). MRI exams generally were of higher diagnostic quality in the immobilizer group than the external fixator group (p < 0.05). The external fixator models included DePuy Synthes, Smith and Nephew, Stryker Hoffman III, Zimmer FastFrame, and Zimmer XtraFix. MRI examinations in patients with external fixators for traumatic knee dislocations can be safely performed under certain conditions and provide diagnostic quality images.
Label-free quantitative phase imaging can potentially measure cellular dynamics with minimal perturbation, motivating efforts to develop faster and more sensitive instrumentation. We characterize ...fast, single-shot quantitative phase gradient microscopy (ss-QPGM) that simultaneously acquires multiple polarization components required to reconstruct phase images. We integrate a computationally efficient least squares algorithm to provide real-time, video-rate imaging (up to 75 frames / s ). The developed instrument was used to observe changes in cellular morphology and correlate these to molecular measures commonly obtained by staining.SignificanceLabel-free quantitative phase imaging can potentially measure cellular dynamics with minimal perturbation, motivating efforts to develop faster and more sensitive instrumentation. We characterize fast, single-shot quantitative phase gradient microscopy (ss-QPGM) that simultaneously acquires multiple polarization components required to reconstruct phase images. We integrate a computationally efficient least squares algorithm to provide real-time, video-rate imaging (up to 75 frames / s ). The developed instrument was used to observe changes in cellular morphology and correlate these to molecular measures commonly obtained by staining.We aim to characterize a fast approach to ss-QPGM and record morphological changes in single-cell phase images. We also correlate these with biochemical changes indicating cell death using concurrently acquired fluorescence images.AimWe aim to characterize a fast approach to ss-QPGM and record morphological changes in single-cell phase images. We also correlate these with biochemical changes indicating cell death using concurrently acquired fluorescence images.Here, we examine nutrient deprivation and anticancer drug-induced cell death in two different breast cell lines, viz., M2 and MCF7. Our approach involves in-line measurements of ss-QPGM and fluorescence imaging of the cells biochemically labeled for viability.ApproachHere, we examine nutrient deprivation and anticancer drug-induced cell death in two different breast cell lines, viz., M2 and MCF7. Our approach involves in-line measurements of ss-QPGM and fluorescence imaging of the cells biochemically labeled for viability.We validate the accuracy of the phase measurement using a USAF1951 pattern phase target. The ss-QPGM system resolves 912.3 lp / mm , and our analysis scheme accurately retrieves the phase with a high correlation coefficient ( ∼ 0.99 ), as measured by calibrated sample thicknesses. Analyzing the contrast in phase, we estimate the spatial resolution achievable to be 0.55 μ m for this microscope. ss-QPGM time-lapse live-cell imaging reveals multiple intracellular and morphological changes during biochemically induced cell death. Inferences from co-registered images of quantitative phase and fluorescence suggest the possibility of necrosis, which agrees with previous findings.ResultsWe validate the accuracy of the phase measurement using a USAF1951 pattern phase target. The ss-QPGM system resolves 912.3 lp / mm , and our analysis scheme accurately retrieves the phase with a high correlation coefficient ( ∼ 0.99 ), as measured by calibrated sample thicknesses. Analyzing the contrast in phase, we estimate the spatial resolution achievable to be 0.55 μ m for this microscope. ss-QPGM time-lapse live-cell imaging reveals multiple intracellular and morphological changes during biochemically induced cell death. Inferences from co-registered images of quantitative phase and fluorescence suggest the possibility of necrosis, which agrees with previous findings.Label-free ss-QPGM with high-temporal resolution and high spatial fidelity is demonstrated. Its application for monitoring dynamic changes in live cells offers promising prospects.ConclusionsLabel-free ss-QPGM with high-temporal resolution and high spatial fidelity is demonstrated. Its application for monitoring dynamic changes in live cells offers promising prospects.
Toll-like receptor-4 has been implicated in modulating ischemia-reperfusion injury in cardiac, hepatic, renal, and cerebral models. However, its role in lung ischemia-reperfusion injury is unknown. ...We hypothesize that toll-like receptor-4 has a key role in initiating the inflammatory cascade in lung ischemia-reperfusion injury.
We used toll-like receptor-4 specific short interference RNA to achieve toll-like receptor-4 knockdown in rats prior to undergoing ischemia and reperfusion. Lungs were explanted and studied for protein expression and markers of lung injury. Additional animals were evaluated for cellular uptake of toll-like receptor-4 short interference RNA. Toll-like receptor-4 short interference RNA localized to the alveolar macrophage.
In animals pretreated with toll-like receptor-4 short interference RNA, toll-like receptor-4 expression and mitogen-activated protein kinase phosphorylation were suppressed. Markers of lung injury including permeability index, myeloperoxidase content, and bronchoalveolar lavage inflammatory cell counts were all reduced with toll-like receptor-4 knockdown.
Toll-like receptor-4 is critical in the development of lung ischemia-reperfusion injury and its activation in the alveolar macrophage may be the initiating step.
Complications after pulmonary resection lead to higher costs of care. Video-assisted thoracoscopic surgery (VATS) for lobectomy is associated with fewer complications, but lower inpatient costs for ...VATS have not been uniformly demonstrated. Because some complications occur after discharge, we compared 90-day costs of VATS lobectomy versus open lobectomy and explored whether differential health care use after discharge might account for any observed differences in costs.
A cohort study (2007-2011) of patients with lung cancer who had undergone resection was conducted using MarketScan-a nationally representative sample of persons with employer-provided health insurance. Total costs reflect payments made for inpatient, outpatient, and pharmacy claims up to 90 days after discharge.
Among 9,962 patients, 31% underwent VATS lobectomy. Compared with thoracotomy, VATS was associated with lower rates of prolonged length of stay (PLOS) (3.0% versus 7.2%; p<0.001), 90-day emergency department (ED) use (22% versus 24%; p=0.005), and 90-day readmission (10% versus 12%; p=0.026). Risk-adjusted 90-day costs were $3,476 lower for VATS lobectomy (p=0.001). Differential rates of PLOS appeared to explain this cost difference. After adjustment for PLOS, costs were $1,276 lower for VATS, but this difference was not significant (p=0.125). In the fully adjusted model, PLOS was associated with the highest cost differential (+$50,820; p<0.001).
VATS lobectomy is associated with lower 90-day costs--a relationship that appears to be mediated by lower rates of PLOS. Although VATS may lead to lower rates of PLOS among patients undergoing lobectomy, observational studies cannot verify this assertion. Strategies that reduce PLOS will likely result in cost-savings that can increase the value of thoracic surgical care.
Abstract Objective Mesenchymal stromal cell–based therapies have demonstrated efficacy in treating a variety of diseases. Despite the potential benefits, there are still significant hurdles that need ...to be overcome for clinical use. We describe a cell-free–based immunotherapy approach for inducing pulmonary ischemic tolerance by using mesenchymal stromal cell–conditioned media. Methods In our well-established lung ischemia–reperfusion model, we pretreated with mesenchymal stromal cell–conditioned media 30 minutes before injury. To determine the degree of lung injury, we assessed for changes in lung vascular permeability, proinflammatory cytokines and cellular infiltrates in bronchoalveolar lavage, and histopathology. Macrophage and T-cell subsets were assessed by immunohistochemistry. Results Pretreatment with mesenchymal stromal cell–conditioned media conferred protection against lung ischemia–reperfusion injury. This protection is characterized by a significant reduction in proinflammatory cytokines, a decrease in infiltrating inflammatory cells, and increases in M2-like macrophages and regulatory T cells. Conclusions Cell-free mesenchymal stromal cell–conditioned media therapy confers pulmonary ischemic tolerance. This therapy uses paracrine factors that provide beneficial protective effects by immunomodulating the inflammatory response in resident and infiltrating cell subsets.
Porous precision-templated scaffolds (PTS) with uniform, interconnected, 40 μm pores have shown favorable healing outcomes and a reduced foreign body reaction (FBR). Macrophage receptor with ...collagenous structure (MARCO) and toll-like receptors (TLRs) have been identified as key surface receptors in the initial inflammatory phase of wound healing. However, the role of MARCO and TLRs in modulating monocyte and macrophage phenotypes within PTS remains uncharacterized. In this study, we demonstrate a synergetic relationship between MARCO and TLR signaling in cells inhabiting PTS, where induction with TLR3 or TLR4 agonists to 40 μm scaffold-resident cells upregulates the transcription of MARCO. Upon deletion of MARCO, the prohealing phenotype within 40 μm PTS polarizes to a proinflammatory and profibrotic phenotype. Analysis of downstream TLR signaling shows that MARCO is required to attenuate nuclear factor kappa B (NF-κB) inflammation in 40 μm PTS by regulating the transcription of inhibitory NFKB inhibitor alpha (
) and interleukin-1 receptor-associated kinase 3 (
), primarily through a
-dependent signaling pathway. Investigation of implant outcome in the absence of MARCO demonstrates an increase in collagen deposition within the scaffold and the development of tissue fibrosis. Overall, these results further our understanding of the molecular mechanisms underlying MARCO and TLR signaling within PTS. Impact statement Monocyte and macrophage phenotypes in the foreign body reaction (FBR) are essential for the development of a proinflammatory, prohealing, or profibrotic response to implanted biomaterials. Identification of key surface receptors and signaling mechanisms that give rise to these phenotypes remain to be elucidated. In this study, we report a synergistic relationship between macrophage receptor with collagenous structure (MARCO) and toll-like receptor (TLR) signaling in scaffold-resident cells inhabiting porous precision-templated 40 μm pore scaffolds through a
-dependent pathway that promotes healing. These findings advance our understanding of the FBR and provide further evidence that suggests MARCO, TLRs, and fibrosis may be interconnected.
•Difficult lung transplantation adversely affects short-term outcomes.•Difficult lung transplantation does not worsen long-term survival.•Modifier-22 is a reasonable marker to identify difficult lung ...transplants.
Lung transplantation (LTx) is a complex operation; however, certain factors can make LTx even more challenging. A difficult LTx could adversely affect immediate and long-term outcomes. We investigate the potential use of Modifier-22 to identify difficult LTx to evaluate postoperative outcomes.
A retrospective analysis was performed on patients who had undergone LTx between January 1, 2010, and October 1, 2018, at the University of Washington. Patients undergoing repeat LTx, other solid organ transplantation, and/or with prior major cardiothoracic surgery were excluded. Patients were classified into 2 categories: standard LTx and difficult LTx groups. We examined hospital length of stay (LOS), intensive care unit (ICU) LOS, duration on the ventilator, and 1-, 3-, and 5-year survival.
A total of 370 patients were identified, with 268 patients in the standard LTx group and 102 patients in the difficult LTx group. The median LOS, ICU LOS, and duration on the ventilator in the difficult LTx group was 18.0 ± 1.6 days, 6.0 ± 1.2 days, and 2.0 ± 0.9 days compared with 15.0 ± 0.8 days, 4.0 ± 0.7 days, and 1.0 ± 0.3 days in the standard LTx group, respectively (all P < .01). Kaplan-Meier analysis revealed that both groups had similar survival.
Modifier-2 can be used to identify challenging LTx. Difficult LTx negatively impacts early postoperative outcomes with longer LOS, ICU LOS, and duration on the ventilator. However, long-term survival was not affected. Clinicians should not view pleural space and anatomical complexities, which are a consequence of the underlying disease, as a risk factor for impaired survival.
Surgical repair or drainage is the standard treatment for benign esophageal perforation. The United States Food and Drug Administration has approved the use of esophageal stents for the management of ...malignant esophageal stricture or fistula, or both. We hypothesize that increasing enthusiasm and experience with esophageal stents has led to greater use of stents for the management of benign esophageal perforation.
We performed a retrospective cohort study (2007 to 2014) of patients with benign esophageal perforation using MarketScan (Thomson Reuters, New York, NY), a commercial claims database. Patients had 6 months of follow-up. Regression was used for risk-adjustment.
Benign esophageal perforation was treated in 659 patients (mean age, 49 years; 41% women), comprising surgical repair in 449 (69%), surgical drainage in 110 (17%), and stent in 100 (15%). Stent use increased from 7% in 2007 to 30% in 2014 (p < 0.001 for trend). Over the same period, surgical repair decreased from 71% to 53% (p = 0.001 for trend), but surgical drainage did not change (p = 0.24). After adjustment for other factors that could vary over time, stent use increased by 28% per year (incidence rate ratio, 1.28; 95% confidence interval, 1.17 to 1.39). Changes in risk-adjusted deaths, discharges home, readmissions, or costs over the same period were not significant (all p > 0.05 for trend).
The use of stents for the management of benign esophageal perforation has increased by over fourfold in just 8 years, but short-term outcomes have not changed over time for this population of patients. A national registry for off-label use of esophageal stents may clarify the indications for and risks and benefits of stenting benign esophageal perforations.
Differential toll-like receptor activation in lung ischemia reperfusion injury Phelan, Patrick, MD; Merry, Heather E., MD; Hwang, Billanna, MPH ...
Journal of thoracic and cardiovascular surgery/The Journal of thoracic and cardiovascular surgery/The journal of thoracic and cardiovascular surgery,
06/2015, Letnik:
149, Številka:
6
Journal Article
Recenzirano
Odprti dostop
Abstract Objective The requirement for toll-like receptors (TLRs) in lung ischemia reperfusion injury (LIRI) has been demonstrated but not fully characterized. Previously, we reported that TLR-4 is ...required by alveolar macrophages but not pulmonary endothelial or epithelial cells for development of LIRI. Additionally, we demonstrated differential patterns of mitogen-activated protein kinase (MAPK) activation and cytokine release in these cell types during LIRI. Here, we sought to determine whether these differences in activation responses are related to cell-specific TLR activation requirements. Methods Primary cultures of alveolar macrophages, pulmonary endothelial, and immortalized epithelial cells were pretreated with TLR-2 or TLR-4 short interference RNA (ribonucleic acid) before hypoxia and reoxygenation. Cell lysates and media were analyzed for receptor knockdown, MAPK activation, and cytokine production. Rats were pretreated with TLR-2 or TLR-4 short interference RNA before lung ischemia reperfusion and changes in lung vascular permeability were assessed. Results Knockdown of TLR-2 in alveolar macrophages did not affect MAPK phosphorylation or cytokine secretion. Conversely, TLR-2 knockdown in pulmonary endothelial and epithelial cells demonstrated significant reductions in extracellular signal-regulated kinase 1/2 activation and cytokine secretion. The lung permeability index in LIRI was decreased by TLR-4 but not TLR-2. Conclusions Differential TLR signaling and MAPK activation in response to LIRI seem to be cell specific. Short interference RNA provides an outstanding tool for examination of the underlying mechanism.
Obese patients with idiopathic pulmonary fibrosis (IPF) have higher 90-day mortality after lung transplantation. We sought to determine whether body mass index (BMI) differentially modified the ...effect of transplant procedure type on 90-day mortality in IPF patients.
We analyzed data from the Organ Procurement and Transplantation Network (OPTN) for all patients with IPF who were transplanted between 2000 and 2010. Post-transplant survival was examined using Kaplan-Meier estimates. Multivariable logistic regression modeling was used to determine the difference in 90-day survival. The primary variable of interest was the interaction term between body mass index (BMI) and transplant type.
A total of 3,389 (58% single-lung transplant SLT and 42% bilateral lung transplant BLT) subjects were included. Multivariable logistic regression modeling demonstrated a statistically significant interaction between BMI and transplant type (p = 0.047). Patients with a BMI > 30 kg/m(2) who received a BLT are 1.71 times (95% CI 1.03 to 2.85, p = 0.038) more likely to die within 90 days than BLT recipients with a BMI of 18.5 to 30 kg/m(2).
Our results suggest that obese patients who receive a BLT may be at higher risk of 90-day mortality compared with patients of normal weight. Further study is needed to obtain more detailed information about comorbidities and other risk factors for early death that are not included in the OPTN database.
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