ASO Visual Abstract: Repeat Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy for Cancers with Peritoneal Metastasis—A 30-year Institutional Experience

Annals of Surgical Oncology -     

Spatiotemporal tracking of cells in tissue‐engineered cardiac organoids

Cardiac tissue engineering aims to create myocardial patches for repair of defective or damaged native heart muscle. The inclusion of non‐myocytes in engineered cardiac tissues has been shown to improve the properties of cardiac tissue compared to tissues engineered from enriched populations of myocytes alone. While attempts have been made to mix non‐myocytes (fibroblasts, endothelial cells) with cardiomyocytes, very little is understood about how the tissue properties are affected by varying the respective ratios of the three cell types and how these cells assemble into functional tissues with time. The goal of this study was to investigate the effects of modulating the ratios of the three cell types and to spatially and temporally track cardiac tri‐cultures of cells. Primary neonatal cardiac fibroblasts and D4T endothelial cells were incubated in 5 µM CellTracker^? green dye and CellTracker^? red dye, respectively, while neonatal cardiomyocytes were labelled with 20 µg/mL DAPI. The non‐myocytes were seeded either sequentially (pre‐culture) or simultaneously (tri‐culture) in Matrigel‐coated microchannels and allowed to form organoids, as in our previous studies. We also varied the seeding percentage of cardiomyocytes while keeping the total cell number constant in an attempt to improve the functional properties of the organoids. Organoids were imaged on days 1 and 4. Endothelial cells were seen to aggregate into clusters when simultaneously tri‐cultured with myocytes and fibroblasts, while pre‐cultures contained elongated cells. Functional properties of organoids were improved by increasing the seeding percentage of enriched cardiomyocytes from 40% to 80%. Copyright © 2009 John Wiley & Sons, Ltd.     

Prospective comparison of novel dark blood late gadolinium enhancement with conventional bright blood imaging for the detection of scar

Background

Conventional bright blood late gadolinium enhancement (bright blood LGE) imaging is a routine cardiovascular magnetic resonance (CMR) technique offering excellent contrast between areas of LGE and normal myocardium. However, contrast between LGE and blood is frequently poor. Dark blood LGE (DB LGE) employs an inversion recovery T2 preparation to suppress the blood pool, thereby increasing the contrast between the endocardium and blood. The objective of this study is to compare the diagnostic utility of a novel DB phase sensitive inversion recovery (PSIR) LGE CMR sequence to standard bright blood PSIR LGE.

Methods

One hundred seventy-two patients referred for clinical CMR were scanned. A full left ventricle short axis stack was performed using both techniques, varying which was performed first in a 1:1 ratio. Two experienced observers analyzed all bright blood LGE and DB LGE stacks, which were randomized and anonymized. A scoring system was devised to quantify the presence and extent of gadolinium enhancement and the confidence with which the diagnosis could be made.

Results

A total of 2752 LV segments were analyzed. There was very good inter-observer correlation for quantifying LGE. DB LGE analysis found 41.5% more segments that exhibited hyperenhancement in comparison to bright blood LGE (248/2752 segments (9.0%) positive for LGE with bright blood; 351/2752 segments (12.8%) positive for LGE with DB; p?<?0.05). DB LGE also allowed observers to be more confident when diagnosing LGE (bright blood LGE high confidence in 154/248 regions (62.1%); DB LGE in 275/324 (84.9%) regions (p?<?0.05)). Eighteen patients with no bright blood LGE were found to have had DB LGE, 15 of whom had no known history of myocardial infarction.

Conclusions

DB LGE significantly increases LGE detection compared to standard bright blood LGE. It also increases observer confidence, particularly for subendocardial LGE, which may have important clinical implications.

     

The Effect of Human-Immunodeficiency Virus Status on Outcomes in Penetrating Abdominal Trauma: An Interim Analysis

Background

The purpose of this study was to determine whether the outcomes of hemodynamically stable patients undergoing exploratory laparotomy for penetrating abdominal trauma differed as a result of their HIV status.

Methods

This was an observational, prospective study from February 2016 to May 2017. All hemodynamically stable patients with penetrating abdominal trauma requiring a laparotomy were included. The mechanism of injury, the HIV status, age, the penetrating abdominal trauma index (PATI), and the revised trauma score (RTS) were entered into a binary logistic regression model. Outcome parameters were in-hospital death, morbidity, admission to intensive care unit (ICU), relaparotomy within 30 days, and length of stay longer than 30 days.

Results

A total of 209 patients, 94% male, with a mean age of 29 ± 10 years were analysed. Twenty-eight patients (13%) were HIV positive. The two groups were comparable. Ten (4.8%) laparotomies were negative. There were two (0.96%) deaths, both in the HIV negative group. The complication rate was 34% (n = 72). Twenty-nine patients (14%) were admitted to the ICU. A higher PATI, older age, and a lower RTS were significant risk factors for ICU admission. After 30 days, 12 patients (5.7%) were still in hospital. Twenty-four patients (11%) underwent a second laparotomy. The PATI score was the single independent predictor for complications, relaparotomy, and hospital stay longer than 30 days.

Conclusions

Preliminary results reveal that HIV status does not influence outcomes in patients with penetrating abdominal trauma.

     

Optical mapping of impulse propagation in engineered cardiac tissue

Cardiac tissue engineering has a potential to provide functional, synchronously contractile tissue constructs for heart repair, and for studies of development and disease using in vivo-like yet controllable in vitro settings. In both cases, the utilization of bioreactors capable of providing biomimetic culture environments is instrumental for supporting cell differentiation and functional assembly. In the present study, neonatal rat heart cells were cultured on highly porous collagen scaffolds in bioreactors with electrical field stimulation. A hallmark of excitable tissues such as myocardium is the ability to propagate electrical impulses. We utilized the method of optical mapping to measure the electrical impulse propagation. The average conduction velocity recorded for the stimulated constructs (14.4 +/- 4.1 cm/s) was significantly higher than that of the nonstimulated constructs (8.6 +/- 2.3 cm/s, p = 0.003). The measured electrical propagation properties correlated to the contractile behavior and the compositions of tissue constructs. Electrical stimulation during culture significantly improved amplitude of contractions, tissue morphology, and connexin-43 expression compared to the nonsimulated controls. These data provide evidence that electrical stimulation during bioreactor cultivation can improve electrical signal propagation in engineered cardiac constructs.     

Keeping it in the family: Use of the grandmother,mother, and child technique to navigate complex anatomy during Coronary sinus Reducer Implantation

The Coronary Sinus Reducer® (CSR) is an emerging therapy for refractory angina recommended once no further pharmacologic or coronary revascularization options are available. We present the case of a 72-year-old man who underwent CSR implantation. Complex coronary sinus anatomy necessitated an innovative “grandmother, mother, and child” catheter approach.     

Synthetic oxygen carriers in cardiac tissue engineering

The prominence of cardiovascular diseases has prompted investigations into alternative treatment options, including tissue engineering. Currently, the biggest limitation in cardiac tissue engineering lies in delivering oxygen to all cells within the construct. Synthetic oxygen carriers hold much promise in that they have high affinity for oxygen and can be supplemented to culture medium without adverse effect on the cells. This review highlights two complementary studies by our group that utilized oxygen carriers in cardiac tissue engineering. Experimental and modeling studies were performed to evaluate the effect of a perfluorocarbon (PFC)-based synthetic oxygen carrier, Oxygent, on oxygen supply within tissue engineered cardiac constructs. Porous biorubber scaffolds with an array of parallel channels mimicking the capillary network were seeded with cardiomyocytes and fibroblasts, and cultivated in medium supplemented with PFC. The presence of PFC enhanced the transport of oxygen, increased oxygen concentrations, and yielded constructs that displayed stronger cardiac-like phenotype.     

Anal sphincter repair for fecal incontinence: experience from a tertiary care centre

Aim  

Structural anal sphincter damage may be secondary to obstetric anal sphincter injury, perineal trauma or anorectal surgery. We reviewed the spectrum of anal sphincter injuries and their outcomes in a tertiary care colorectal unit.