Advanced 3D In Vitro Lung Fibrosis Models: Contemporary Status, Clinical Uptake, and Prospective Outlooks

Fibrosis has been characterized as a global health problem and ranks as one of the primary causes of organ dysfunction. Currently, there is no cure for pulmonary fibrosis, and limited therapeutic options are available due to an inadequate understanding of the disease pathogenesis. The absence of advanced in vitro models replicating dynamic temporal changes observed in the tissue with the progression of the disease is a significant impediment in the development of novel antifibrotic treatments, which has motivated research on tissue-mimetic three-dimensional (3D) models. In this review, we summarize emerging trends in preparing advanced lung models to recapitulate biochemical and biomechanical processes associated with lung fibrogenesis. We begin by describing the importance of in vivo studies and highlighting the often poor correlation between preclinical research and clinical outcomes and the limitations of conventional cell culture in accurately simulating the 3D tissue microenvironment. Rapid advancement in biomaterials, biofabrication, biomicrofluidics, and related bioengineering techniques are enabling the preparation of in vitro models to reproduce the epithelium structure and operate as reliable drug screening strategies for precise prediction. Improving and understanding these model systems is necessary to find the cross-talks between growing cells and the stage at which myofibroblasts differentiate. These advanced models allow us to utilize the knowledge and identify, characterize, and hand pick medicines beneficial to the human community. The challenges of the current approaches, along with the opportunities for further research with potential for translation in this field, are presented toward developing novel treatments for pulmonary fibrosis.

Rationale and Design of the Randomized Bayesian Multicenter COME-TAVI Trial in Patients With a New Onset Left Bundle Branch Block

Patients with new-onset left bundle branch block (LBBB) after transcatheter aortic valve implantation (TAVI) are at risk of developing delayed high-degree atrioventricular block. Management of new-onset LBBB post-TAVI remains controversial. In the Comparison of a Clinical Monitoring Strategy Versus Electrophysiology-Guided Algorithmic Approach in Patients With a New LBBB After TAVI (COME-TAVI) trial, consenting patients with new-onset LBBB that persists on day 2 after TAVI, meeting exclusion/inclusion criteria, are randomized to an electrophysiological study (EPS)-guided approach or 30-day electrocardiographic monitoring. In the EPS-guided approach, patients with a His to ventricle (HV) interval ≥ 65 ms undergo permanent pacemaker implantation. Patients randomized to noninvasive monitoring receive a wearable continuous electrocardiographic recording and transmitting device for 30 days. Follow-up will be performed at 3, 6, and 12 months. The primary endpoint is a composite outcome designed to capture net clinical benefit. The endpoint incorporates major consequences of both strategies in patients with new-onset LBBB after TAVI, as follows: (i) sudden cardiac death; (ii) syncope; (iii) atrioventricular conduction disorder requiring a pacemaker (for a class I or IIa indication); and (iv) complications related to the pacemaker or EPS. The trial incorporates a Bayesian design with a noninformative prior, outcome-adaptive randomization (initially 1:1), and 2 prespecified interim analyses once 25% and 50% of the anticipated number of primary endpoints are reached. The trial is event-driven, with an anticipated upper limit of 452 patients required to reach 77 primary outcome events over 12 months of follow-up. In summary, the aim of this Bayesian multicentre randomized trial is to compare 2 management strategies in patients with new-onset LBBB post-TAVI-an EPS-guided approach vs noninvasive 30-day monitoring. Trial registration number: NCT03303612.

A correlation study between mean platelet volume and platelet aggregation study in acute coronary syndrome patients

INTRODUCTION

Platelets play an important role in cardiovascular disease mainly in the development of acute thrombotic events. Elevated platelet indices have been proposed as a risk factor for acute coronary syndrome (ACS). It remains uncertain whether increased platelet indices are the result or the cause of ACS.

AIM AND OBJECTIVE

This study aimed to correlate mean platelet volume (MPV) and platelet aggregation response to know the functional status of platelets based on their size.

MATERIALS AND METHODS

A total of 50 patients with ST-segment elevation ACS (STE-ACS) or non-ST-segment elevation ACS (NSTE-ACS) were included and their MPV was measured and platelet aggregometry was performed. Patients were divided into two groups, patients with MPV ≤9.1 fl as group 1 and those with MPV >9.1 fl as group 2. The mean maximum platelet aggregation response (MMPAR) with ADP, Collagen, and Epinephrine, of both the groups, were compared. MMPAR to ADP, Collagen, and Epinephrine in group 1 was 74.47%, 66.13%, and 72.9%, respectively, and in group 2, 72.94%, 59.97%, and 72.43%, respectively. There was no statistically significant difference in the MMPAR to ADP, Collagen, and Epinephrine among the two groups.

CONCLUSION

Increased MPV does not indicate the platelets are hyperreactive. An increase in MPV may be because of the increased release of immature platelets from bone marrow as there is increased consumption of platelets at the site of thrombus formation in ACS.

A Computed Tomography Protocol to Evaluate Coronary Artery Disease Before Transcatheter Aortic Valve Replacement

BACKGROUND

Transcatheter aortic valve replacement (TAVR) computed tomographic angiography (CTA) images can be used to evaluate coronary artery disease (CAD).

METHODS

We conducted a prospective cohort study of consecutive TAVR patients from November 2019 to February 2021 to evaluate TAVR CTA assessment of CAD on the rate of pre-TAVR invasive angiography. Patients had CTA first or invasive angiography first at the discretion of their treating physicians. TAVR CTA scans were categorised as normal/mild CAD, single-vessel disease, high risk (multivessel or left main disease), or nondiagnostic in patients without previous coronary artery bypass grafting (CABG) and as low risk or high risk in patients with previous CABG. Invasive angiography was recommended before TAVR for high-risk or nondiagnostic CTA findings.

RESULTS

TAVR was performed on 354 patients; CTA first was performed in 273 and invasive angiography first in 81. Among 231 patients without previous CABG who had CTA first, 22.1% (51/231) had pre-TAVR invasive angiography and 1.3% (3/231) had pre-TAVR revascularisation. Normal/mild CAD or single-vessel disease was found on CTA in 174 patients, of whom 0.5% (1/174) had high-risk disease on invasive angiography. Among 42 patients with previous CABG who had CTA first, 14.3% (6/42) had pre-TAVR invasive angiography and 2.4% (1/42) had pre-TAVR revascularisation.

CONCLUSION

TAVR CTA CAD evaluation can avoid pre-TAVR invasive angiography in more than 70% of patients while rarely missing high risk findings. A CTA-first strategy to assess CAD should be considered, especially among patients where conservative management of CAD is preferred.

Factors associated with mortality among moderate and severe patients with COVID-19 in India: a secondary analysis of a randomised controlled trial

OBJECTIVE

Large data on the clinical characteristics and outcome of COVID-19 in the Indian population are scarce. We analysed the factors associated with mortality in a cohort of moderately and severely ill patients with COVID-19 enrolled in a randomised trial on convalescent plasma.

DESIGN

Secondary analysis of data from a Phase II, Open Label, Randomized Controlled Trial to Assess the Safety and Efficacy of Convalescent Plasma to Limit COVID-19 Associated Complications in Moderate Disease.

SETTING

39 public and private hospitals across India during the study period from 22 April to 14 July 2020.

PARTICIPANTS

Of the 464 patients recruited, two were lost to follow-up, nine withdrew consent and two patients did not receive the intervention after randomisation. The cohort of 451 participants with known outcome at 28 days was analysed.

PRIMARY OUTCOME MEASURE

Factors associated with all-cause mortality at 28 days after enrolment.

RESULTS

The mean (SD) age was 51±12.4 years; 76.7% were males. Admission Sequential Organ Failure Assessment score was 2.4±1.1. Non-invasive ventilation, invasive ventilation and vasopressor therapy were required in 98.9%, 8.4% and 4.0%, respectively. The 28-day mortality was 14.4%. Median time from symptom onset to hospital admission was similar in survivors (4 days; IQR 3-7) and non-survivors (4 days; IQR 3-6). Patients with two or more comorbidities had 2.25 (95% CI 1.18 to 4.29, p=0.014) times risk of death. When compared with survivors, admission interleukin-6 levels were higher (p<0.001) in non-survivors and increased further on day 3. On multivariable Fine and Gray model, severity of illness (subdistribution HR 1.22, 95% CI 1.11 to 1.35, p<0.001), PaO₂/FiO₂ ratio <100 (3.47, 1.64-7.37, p=0.001), neutrophil lymphocyte ratio >10 (9.97, 3.65-27.13, p<0.001), D-dimer >1.0 mg/L (2.50, 1.14-5.48, p=0.022), ferritin ≥500 ng/mL (2.67, 1.44-4.96, p=0.002) and lactate dehydrogenase ≥450 IU/L (2.96, 1.60-5.45, p=0.001) were significantly associated with death.

CONCLUSION

In this cohort of moderately and severely ill patients with COVID-19, severity of illness, underlying comorbidities and elevated levels of inflammatory markers were significantly associated with death.

TRIAL REGISTRATION NUMBER

CTRI/2020/04/024775.

COVID-19 pandemic and coronary angiography for ST-elevation myocardial infarction, use of mechanical support and mechanical complications in Canada; a Canadian Association of Interventional Cardiology national survey

Background

As a result of the COVID-19 pandemic first wave, reductions in ST-elevation myocardial infarction (STEMI) invasive care, ranging from 23% to 76%, have been reported from various countries. Whether this change had any impact on coronary angiography (CA) volume or on mechanical support device use for STEMI and post-STEMI mechanical complications in Canada is unknown.

Methods

We administered a Canada-wide survey to all cardiac catheterization laboratory directors, seeking the volume of CA use for STEMI performed during the period from March 1 2020 to May 31, 2020 (pandemic period), and during 2 control periods (March 1, 2019 to May 31, 2019 and March 1, 2018 to May 31, 2018). The number of left ventricular support devices used, as well as the number of ventricular septal defects and papillary muscle rupture cases diagnosed, was also recorded. We also assessed whether the number of COVID-19 cases recorded in each province was associated with STEMI-related CA volume.

Results

A total of 41 of 42 Canadian catheterization laboratories (98%) provided data. There was a modest but statistically significant 16% reduction (incidence rate ratio [IRR] 0.84; 95% confidence interval 0.80-0.87) in CA for STEMI during the first wave of the pandemic, compared to control periods. IRR was not associated with provincial COVID-19 caseload. We observed a 26% reduction (IRR 0.74; 95% confidence interval 0.61-0.89) in the use of intra-aortic balloon pump use for STEMI. Use of an Impella pump and mechanical complications from STEMI were exceedingly rare.

Conclusions

We observed a modest 16% decrease in use of CA for STEMI during the pandemic first wave in Canada, lower than the level reported in other countries. Provincial COVID-19 caseload did not influence this reduction.

Interventions supporting long term adherence and decreasing cardiovascular events after myocardial infarction (ISLAND): pragmatic randomised controlled trial

OBJECTIVE

To test a scalable health system intervention to improve long term adherence to secondary prevention treatments among patients who have had a recent myocardial infarction.

DESIGN

Three arm, pragmatic randomised controlled trial with blinded outcome assessment.

SETTING

Nine cardiac centres in Ontario, Canada.

PARTICIPANTS

2632 patients with obstructive coronary artery disease after a myocardial infarction, identified from a centralised cardiac registry.

INTERVENTIONS

Participants were randomised 1:1:1 to receive usual care, five mail-outs developed through a user centred design process, or mail-outs plus phone calls. The phone calls were delivered first by an interactive automated system to screen for non-adherence to treatment. Trained lay health workers followed up as necessary. Interventions were coordinated centrally but delivered from each patient's hospital site.

MAIN OUTCOME MEASURES

Co-primary outcomes were completion of cardiac rehabilitation and adherence to recommended medication. Data were collected by blinded assessors through patient report and from administrative health databases at 12 months.

RESULTS

2632 patients (mean age 66, 71% male) were randomised: 878 to the full intervention (mail plus phone calls), 878 to mail only, and 876 to usual care. Of the respondents, 174 (27%) of 643 in the usual care group, 200 (32%) of 628 in the mail only group, and 196 (37%) of 531 allocated to the full intervention completed cardiac rehabilitation (adjusted odds ratio 1.55, 95% confidence interval 1.18 to 2.03). In the mail plus phone group, 11.7%, 6.0%, 14.4%, 32.9%, and 35.0% reported adherence to 0, 1, 2, 3, and 4 drug classes after one year, respectively, in comparison with 12.5%, 6.8%, 13.6%, 30.2%, and 36.8% in the mail only group, and 12.2%, 8.4%, 13.1%, 30.3%, and 36.1% in the usual care group, respectively (mail only v usual care, odds ratio 0.98, 95% confidence interval 0.81 to 1.19; full intervention v usual care, 0.99, 0.82 to 1.20).

CONCLUSIONS

Scalable interventions delivered by mail plus phone can increase completion of cardiac rehabilitation after myocardial infarction but not adherence to medication. More intensive interventions should be tested to improve adherence to medication and to evaluate the association between attendance at cardiac rehabilitation and adherence to medication.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02382731, registered 9 March 2015 before any patient enrolment.

Field Implementation of Remote Ischemic Conditioning in ST-Segment-Elevation Myocardial Infarction: The FIRST Study

BACKGROUND

Remote ischemic conditioning (RIC) is a noninvasive therapeutic strategy that uses brief cycles of blood pressure cuff inflation and deflation to protect the myocardium against ischemia-reperfusion injury. We sought to compare major adverse cardiovascular events (MACE) for patients who received RIC before PCI for ST-segment-elevation myocardial infarction (STEMI) compared with standard care.

METHODS

We conducted a pre- and postimplementation study. In the preimplementation phase, STEMI patients were taken directly to the PCI lab. After implementation, STEMI patients received 4 cycles of RIC by paramedics or emergency department staff before PCI. The primary outcome was MACE at 90 days. Secondary outcomes included MACE at 30, 60, and 180 days. Inverse probability of treatment weighting using propensity scores estimated causal effects independent from baseline covariables.

RESULTS

A total of 1667 (866 preimplementation, 801 postimplementation) patients were included. In the preimplementation phase, 13.4% had MACE at 90 days compared with 11.8% in the postimplementation phase (odds ratio [OR] 0.86, 95% CI 0.62-1.21). There were no significant differences in MACE at 30, 60, and 180 days. Patients presenting with cardiogenic shock or cardiac arrest before PCI were less likely to have MACE at 90 days (42.7% pre vs 27.8% post) if they received RIC before PCI (OR 0.52, 95% CI 0.27-0.98).

CONCLUSIONS

A strategy of RIC before PCI for STEMI did not reduce 90-day MACE. Future research should explore the impact of RIC before PCI for longer-term clinical outcomes and for patients presenting with cardiogenic shock or cardiac arrest.

4071Early changes in quality of life after transcatheter aortic valve replacement: One-year results from the 3M TAVR Study

Background

In patients with severe calcific aortic stenosis, transcatheter aortic valve replacement (TAVR) has been shown to significantly improve quality of life (QOL). However, changes in QOL at early follow-up (<1 month), and following next-day discharge are poorly understood.

Methods

A total of 411 patients at 13 centers were enrolled in the Multimodality, Multidisciplinary but Minimalist TAVR (3M TAVR) study in 2015–2017. QOL was evaluated using the Kansas City Cardiomyopathy Questionnaire (KCCQ-12) in participants with a baseline score and at least one score at 2 weeks, 30 days and 1 year. Study endpoints were change in (1) KCCQ-Overall Summary Score (KCCQ-OS) and (2) minimal clinically important differences (MCID). Mixed effects models were used to explore patterns of change from baseline, with fixed terms for time, status at 1-year and their interaction terms, and a random intercept for subject to account for within subject correlation. Descriptive statistics were used to report MCID.

Results

Data were available for 358 (87.1%) participants. 216 (60.3%) were men with a median age 84.0 and STS 5.0 There was significant increase in QOL 2 weeks after TAVR (p≤0.01), and further significant improvement at the 1-month timepoint (p<0.01) for participants who were alive at 1 year. Sex, age category, and STS score category did not have a significant effect on the change in QOL (p>0.05). In the first 2 weeks, moderate (10–20 points) and large (>20 points) improvements were observed in 19.9% and 49.0% of the surviving patients, respectively; at 1-year, similar MCID were seen in 14.6% and 64.0% respectively.

Figure 1

Conclusion

This is the first study to report significant increase in QOL 2 weeks after TAVR, with sustained improvement during the first year in patients treated with the Vancouver TAVR Clinical Pathway with a goal of next-day discharge. Further studies are necessary to determine whether alternative TAVR clinical pathways yield similar findings.

Acknowledgement/Funding

Investigator-initiated unrestricted research grant, Edwards

Myosin IIA and formin dependent mechanosensitivity of filopodia adhesion

Filopodia, dynamic membrane protrusions driven by polymerization of an actin filament core, can adhere to the extracellular matrix and experience both external and cell-generated pulling forces. The role of such forces in filopodia adhesion is however insufficiently understood. Here, we study filopodia induced by overexpression of myosin X, typical for cancer cells. The lifetime of such filopodia positively correlates with the presence of myosin IIA filaments at the filopodia bases. Application of pulling forces to the filopodia tips through attached fibronectin-coated laser-trapped beads results in sustained growth of the filopodia. Pharmacological inhibition or knockdown of myosin IIA abolishes the filopodia adhesion to the beads. Formin inhibitor SMIFH2, which causes detachment of actin filaments from formin molecules, produces similar effect. Thus, centripetal force generated by myosin IIA filaments at the base of filopodium and transmitted to the tip through actin core in a formin-dependent fashion is required for filopodia adhesion.

A mononuclear iron carbonyl complex [Fe(μ-bdt)(CO)2(PTA)2] with bulky phosphine ligands: a model for the [FeFe] hydrogenase enzyme active site with an inverted redox potential

A mononuclear hexa-coordinated iron carbonyl complex [Fe(μ-bdt)(CO)₂(PTA)₂] 1 (bdt = 1,2-benzenedithiolate; PTA = 1,3,5-triaza-7-phosphaadamantane) with two bulky phosphine ligands in the trans position was synthesized and characterized by X-ray structural analysis coulometry data, FTIR, electrochemistry and electronic structure calculations. The complex undergoes a facilitated two-electron reduction 1/1^2- and shows an inverted one-electron reduction for 1/1^- at higher potentials. Electrochemical investigations of 1 are compared to the closely related [Fe(bdt)(CO)₂(PMe₃)₂] compound. A mechanistic suggestion for the hydrogen evolution reaction upon proton reduction from acid media is derived. The stability of 1 in both weak and strong acids is monitored by cyclic voltammetry.

Interventions Supporting Long-term Adherence aNd Decreasing cardiovascular events (ISLAND): Pragmatic randomized trial protocol

BACKGROUND

Guidelines recommend cardiac rehabilitation and long-term use of cardiac medications for most patients who have had a myocardial infarction (MI), but adherence to these secondary prevention treatments is suboptimal.

METHODS

This is a multicenter, pragmatic, 3-arm randomized trial. Eligible patients (n = 2,742) with obstructive coronary artery disease are randomized post-MI to usual care or 1 of 2 intervention arms. Patients in the first intervention arm receive mail-outs sent on behalf of their cardiologist at 4, 8, 20, 32, and 44 weeks post-MI; content is designed to address determinants of adherence and facilitate discussion between the patient and their health care team. Patients in the second intervention arm receive mail-outs plus automated interactive voice response system telephone calls 2 weeks after each letter, as well as a telephone call by trained lay health workers if the interactive voice response system identifies challenges with adherence. Outcomes are assessed 12 months post-MI via patient self-report and administrative data sources. Co-primary outcomes are adherence to cardiac medications and completion of cardiac rehabilitation. Secondary outcomes include cardiovascular events and mortality. An embedded, theory-informed process evaluation will explore the mechanism of action; an economic evaluation is also planned.

CONCLUSIONS

We describe a complete program evaluation of a highly pragmatic, health-system intervention to support adherence to recommended treatments. Research ethics boards approved waiver of consent for patients enrolled in the trial with provision of multiple opportunities to opt out and a debrief at the time of outcome assessment. The methods used here may provide a model for similar interventions.

A survey of doctors at a UK teaching hospital to assess understanding of recent changes to consent law

BACKGROUND

The UK Supreme Court recently ruled that when consenting patients for treatments or procedures, clinicians must also discuss any associated material risks. We surveyed medical staff at a large UK teaching hospital in order to ascertain knowledge of consent law and current understanding of this change.

MATERIALS AND METHODS

Email survey sent to medical staff in all specialities at Norfolk and Norwich University Hospital in February 2016.

RESULTS

245 responses (141 Consultants and 104 junior doctors, response rate 32%). 82% consent patients for procedures at least monthly and 23% daily. 31% were not familiar with the concept of material risk. 35% were familiar with the recent change in consent law, 41% were not. 18% were "very uncertain" and 64% "a little uncertain" that their consenting process meets current legal requirements. >92% think that landmark cases and changes in law should be discussed through professional bodies and circulated better locally.

CONCLUSION

The majority were not familiar with the concept of material risk and recent legal changes. A majority were not confident that their practice meets current requirements, suggesting that recent changes in consent law may not be widely understood at this hospital. We suggest more guidance and education may be necessary than is currently available. Increased understanding of recent changes to consent law will reduce the risk taken by NHS trusts and offer patients a service compliant with Supreme Court guidance.

Abdominal wall ectopic testis torsion mimicking a Spigelian hernia in an adult

We report an unusual case of an ectopic testis identified in a 37-year-old man presenting with acute severe right iliac fossa pain and an irreducible mass. Initially diagnosed as a Spigelian hernia, computed tomography and ultrasonography identified the presence of an ectopic testis in the abdominal wall. Interparietal testicular ectopia is an extremely rare condition. We present and discuss the first case in the literature of an ectopic testis located between the internal and external oblique muscle layers of the anterior abdominal wall in an adult.

Synthesis and characterization of cardo-based phosphorous–containing flame-retardant aromatic polyesters

Phosphorous-containing cardo polyesters were synthesized by interfacial polycondensation of phenylphosphonic dichloride with various bisphenols using a phase-transfer catalyst at ambient temperature. The structure of the synthesized polymers was confirmed using Fourier transform infrared and proton, carbon 13, and phosphorous 31 nuclear magnetic resonance spectroscopic techniques. The thermal properties of the polymers were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry under nitrogen atmosphere. All the polyesters showed high thermal stability, the maximum decomposition temperature being in the range of 475–523°C. The TGA data showed that all the synthesized phosphorous-containing polyesters produce high char yield at 700°C due to the presence of phosphorous atom in the polymer chain and hence have good flame-retardant properties. The synthesized phosphorus-containing polyesters have tensile strength in the range of 38.2–48 MPa, and the percentage of elongation at breaks of 3.3–16.8. The flame retardancy of all synthesized polymers was investigated by limiting oxygen index (LOI) and vertical burning (UL-94) tests. The results showed that the synthesized polymers have excellent flame retardancy, that is, the polymer samples achieved an increased UL-94 rating and the LOI values were in the range of 28.5–34. Broido model has been used to study the thermal degradation kinetic parameters.

Giant Cell Lesions of Lungs: A Histopathological and Morphometric Study of Seven Autopsy Cases

INTRODUCTION

Macrophages undergo fusion to form multinucleated giant cells (MGC) in several pathologic conditions. The exact mechanism of their generation is still unclear. MGC are a common feature of granulomas that develop during various inflammatory reactions.

AIM

To study the histopathological features of giant cell lesions in lungs and correlate the characteristics of giant cells with other histopathological findings. Also, to determine the utility of morphometry to differentiate foreign body and Langhans MGC.

MATERIALS AND METHODS

Seven cases were analysed. Specimen of lungs was grossed, sectioned and processed. Routinely, tissue sections were stained by Haematoxylin and Eosin (H&E) stain. Polarizing microscopy and special stains were employed in selected cases. Granulomas and MGC were counted and measured. Several other parameters like location, distribution, type and number of MGC, associated predominant inflammatory component and nature of granulomas were analysed.

RESULTS

Five patterns of lesions were observed in seven cases. Aspiration pneumonia was seen in three cases (42.85%) and constituted the most common pattern. However, aspiration pneumonia as the only cause of MGC was seen in only one case (14.28%). Pulmonary tuberculosis and asteroid bodies constituted two cases (28.57%) each. Cryptococcal pneumonia and cholesterol clefts constituted one case (14.28%) each. Crypococci were demonstrated to be positively birefringent by polarized microscopy on Ziehl-Neelsen stained sections. Based on statistical analysis of morphometric data, a new index (NP index) was proposed to statistically categorize MGC into foreign body type and Langhans type. NP index value of ≤0.016 was found to be statistically significant (p<0.005) in foreign body MGC. It had high sensitivity and efficacy.

CONCLUSION

MGC may not be always associated with granulomas. The mechanisms that lead to the occurrence of MGC, independent of granuloma needs to be elucidated. Morphometry may serve as a useful aid. But a pathologist has to rely on the morphological details to categorize MGC.

Double Right Coronary Artery Originating from Separate Ostia: A Report of Two Cases

Context:

Coronary artery anomalies are uncommon and most are incidental findings. Double right coronary artery (RCA) is a very rare coronary artery anomaly.

Case Report:

We report two cases of double RCA incidentally found in electrocuted patients. Both cases showed double RCA arising from separate ostia. On microscopy, both right coronaries showed no significant pathology in the first case while in the second case, the posterior RCA showed features of obliterative arteritis.

Conclusion:

Although double coronary artery has been regarded as hemodynamically insignificant, it may be associated with atherosclerosis, acute coronary syndromes, and other anomalies. It is important to know the anatomic variants. Meticulous grossing and careful observation could unearth hidden anomalies.

Increase in upper tropospheric and lower stratospheric aerosol levels and its potential connection with Asian pollution

Satellite observations have shown that the Asian Summer Monsoon strongly influences the upper troposphere and lower stratosphere (UTLS) aerosol morphology through its role in the formation of the Asian Tropopause Aerosol Layer (ATAL). Stratospheric Aerosol and Gas Experiment II solar occultation and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar observations show that summertime UTLS Aerosol Optical Depth (AOD) between 13 and 18 km over Asia has increased by three times since the late 1990s. Here we present the first in situ balloon measurements of aerosol backscatter in the UTLS from Western China, which confirm high aerosol levels observed by CALIPSO since 2006. Aircraft in situ measurements suggest that aerosols at lower altitudes of the ATAL are largely composed of carbonaceous and sulfate materials (carbon/sulfur elemental ratio ranging from 2 to 10). Back trajectory analysis from Cloud-Aerosol Lidar with Orthogonal Polarization observations indicates that deep convection over the Indian subcontinent supplies the ATAL through the transport of pollution into the UTLS. Time series of deep convection occurrence, carbon monoxide, aerosol, temperature, and relative humidity suggest that secondary aerosol formation and growth in a cold, moist convective environment could play an important role in the formation of ATAL. Finally, radiative calculations show that the ATAL layer has exerted a short-term regional forcing at the top of the atmosphere of -0.1 W/m² in the past 18 years.

KEY POINTS

Increase of summertime upper tropospheric aerosol levels over Asia since the 1990s Upper tropospheric enhancement also observed by in situ backscatter measurements Significant regional radiative forcing of -0.1 W/m².

Proline, glutamic acid and leucine-rich protein-1 is essential for optimal p53-mediated DNA damage response

Proline-, glutamic acid- and leucine-rich protein-1 (PELP1) is a scaffolding oncogenic protein that functions as a coregulator for a number of nuclear receptors. p53 is an important transcription factor and tumor suppressor that has a critical role in DNA damage response (DDR) including cell cycle arrest, repair or apoptosis. In this study, we found an unexpected role for PELP1 in modulating p53-mediated DDR. PELP1 is phosphorylated at Serine1033 by various DDR kinases like ataxia-telangiectasia mutated, ataxia telangiectasia and Rad3-related or DNAPKc and this phosphorylation of PELP1 is important for p53 coactivation functions. PELP1-depleted p53 (wild-type) breast cancer cells were less sensitive to various genotoxic agents including etoposide, camptothecin or γ-radiation. PELP1 interacts with p53, functions as p53-coactivator and is required for optimal activation of p53 target genes under genomic stress. Overall, these studies established a new role of PELP1 in DDRs and these findings will have future implications in our understanding of PELP1's role in cancer progression.

Endovascular coil occlusion of traumatic intradural aneurysm with presentation as carotid cavernous fistula

Carotid cavernous fistulae (CCF) are abnormal communication between cavernous segment of the internal carotid artery and cavernous sinus. These entities are usually encountered in 0.2-0.8% of patients with traumatic skull base fractures. Traumatic cerebral aneurysms are rare and account for less than 1% of intracranial aneurysms. CCF due to ruptured intradural traumatic aneurysm is very rare and difficult to treat by surgical methods. We present one such case of a 40-year-old man with post-traumatic CCF due to a ruptured intradural aneurysm successfully treated with endovascular embolization.

Abstract P5-11-02: Radiation instigates EMT, CSC self renewal and pluripotency signal transduction in non-targeted (bystander) ERa+ and triple-negative breast cancer cells

Ascertaining radiation-induced bystander response in non-targeted tumor cells, particularly on variables pertaining to resistance, relapse and tumor progression, may escort significant clinical implications. Accordingly, in this study, we investigated the radiation induced alterations in factors that drive the epithelial-to-mesenchymal transition (EMT), cancer stem cells (CSCs) self-renewal capacity and pluripotency maintenance in non-targeted breast (ERa+ MCF-7 and triple-negative MDA-MB-468) adenocarcinoma cells. Co-cultures of non-targeted breast cancer cells with irradiated (5Gy) counterparts for 24h were assessed for transcriptional regulation of 93 stem cell related molecules using QPCR profiling. Radiation-induced alterations in the expression of ABCG2, E-Cadherin, N-Cadherin, MYC, Nanog and SOX2 in bystander MCF-7 and MDA-MB-468 were assessed using western blot analysis. Radiation profoundly increased the transcriptional activation of stem-cell related molecules in distant bystander ERα+ MCF-7 (70 genes) and in triple-negative MDA-MB-468 (82 genes) cells. Interestingly, 62 of 70 genes activated in MCF-7 and 81 of 82 genes in MDA-MB-468 showed significant (&gt;2 fold) upregulation. Evidently, radiation induced 66 genes (&gt;2 fold, 58 genes) in bystander breast cancer cells independent of their hormone status. Consistently, immunoblotting revealed increase in the expression of ABCG2, N-Cadherin, MYC, Nanog and SOX2 in both MCF7 and MDA-MB-468. Together, these data demonstrates that radiation activates the EMT, CSCs self-renewal and pluripotency maintaining factors in non-targeted bystander cells and could thus play an instrumental role in breast cancer relapse and progression.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-11-02.

Abstract P6-09-05: Neem leaf extract, rich in nimbolide and azadirachtin targets radiation-induced stemness in surviving breast cancer cells

Recently, we have shown that the neem leaf extract (NLE) rich in Nimbolide and Azadirachtin exerted radiosensitization and alleviates tumor progression in varied solid tumor models. Accordingly, in this study, we investigated its potential in the regulation of radiation (IR)-induced stemness in surviving breast cancer (BCa) cells. Human breast adenocarcinoma (MCF-7) cells either mock-irradiated or exposed to IR (2Gy) with or without NLE (1, 10 or 100μg) pre-treatment (for 3h) and analyzed at 3h or 24h post-IR. Transcriptional alterations of 93 molecules that drive EMT, CSCs self-renewal capacity and pluripotency maintenance were analyzed using QPCR profiling. NANOG, SOX2, ABCG2, N-cadherin, E-cadherin and GSK3β expression was examined by immunoblotting. Radiation profoundly increased 67 stem-cell related molecules in surviving BCa cells. NLE exerted a dose-dependent (1μg, 23; 10μg, 51; 100μg, 64 genes) inhibition of IR-induced stem-cell related molecules. Second-phase observations at 24h post-IR revealed no recovery of NLE-inhibited transcription with complete inhibition of 12, 66 and 64 genes after 1, 10 and 100μg. Gene comparison analysis revealed both ‘dose-independent’ (20genes at 3h and 12genes at 24h) and ‘time-independent’ (6, 50 and 61 genes at 1μg, 10μg and 100μg respectively) inhibition. Interestingly, six genes (BMP4, CDH1, EGF3, FOXA2, GSK3β and HDAC2) showed both ‘time-and-dose-independent’ inhibition. Coherently, immunoblotting revealed a consistent regulation of IR-induced NANOG, SOX2, ABCG2, N-cadherin in the surviving BCa cells. Together these data demonstrate that NLE targets IR-induced stemness in surviving BCa cells and may thus serve as a potential “deliverable” to negate breast cancer relapse and progression.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-09-05.

Abstract P4-16-02: EF24 targets radiation-induced NFkB-dependent stemness in triple negative breast cancer cells

Prognosis of patients with late stage BCa still remains poor, mostly due to development of chemoradioresistance followed by tumor recurrence. Cancer stem cells (CSCs), with higher drug efflux capability, and other stem cell-like properties were proposed to be responsible for resistance, relapse and progression of BCa. We have shown that EF24 alleviates radiation (IR)-orchestrated NFkB mediated clonal expansion. Herein, we investigated the potential of EF24 in the regulation of IR-induced NFkB dependent stemness in triple negative breast cancer cells (TNBC). MDA-MB-231 cells exposed to mock-IR or IR (2Gy) with/without EF24 were examined for transcriptional alterations of 93 EMT, CSCs self-renewal, pluoripotentcy maintenance and other stem cell markers. NFkB (p50/p65) overexpression (with or without EF24) and RelA siRNA knockout (with IR) approach were used to delineate the role of IR-induced NFkB and the selective NFkB targeting of EF24 in this setting. Nanog, Sox-2, ABCG-2, N-Cadherin, POU5F1 and Myc expression was examined with immunoblotting. IR profoundly increased the transactivation of 86 stem-cell related molecules in TNBCs that are involved in cell survival. Interestingly, muting IR-induced NFkB attenuated 85 of those genes. Notably, EF24 suppressed identical 85 genes reproducing the inhibitory signature of NFkB muting. Coherently, activating NFkB induced 87 stem-cell related molecules in TNBC and of which 86 genes were completely suppressed with EF24. Alterations in the cellular expression levels of Nanog, Sox-2, ABCG-2, N-Cadherin, POU5F1 and Myc validates the potential of EF24 in mitigating IR-induced stemness in TNBC. Together these data demonstrates, at least in TNBC cells, IR-induced NFkB mediates increased stem-like characteristics and further imply that EF24 may alleviate stemness by selectively targeting IR-induced NFkB.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-16-02.