Light-Activated Vascular Anastomosis.

Background. There have been few advances in technique since vascular anastomosis was performed with silk suture on a curved needle in 1902. This technique results in disruption of the endothelium with exposed intraluminal suture, both of which may lead to thrombocyte aggregation, intimal hyperplasia, and vascular stenosis. A variety of alternative techniques have been explored, with limited success. Photochemical tissue bonding (PTB) is a light-activated methodology of rapidly cross-linking tissue interfaces at the molecular level. Herein, we describe a new technique for anastomosis of venous interposition graft in an ovine model of femoral artery bypass utilizing PTB. Methods. Polypay specific pathogen free sheep (n = 5; 40-45 kg) underwent femoral artery bypass utilizing saphenous vein. The femoral artery was transected and reversed saphenous vein was implanted as an interposition graft. The proximal anastomosis was created as a vein-over-artery cuff utilizing PTB, and the distal anastomosis was created with standard interrupted 8-0 polypropylene suture. Four weeks post-index operation, femoral angiogram was performed to evaluate patency, tortuosity, and luminal diameter. All bypass grafts were harvested and longitudinal and transverse histological sections from the proximal anastomosis were analyzed. Results. The PTB anastomoses (n = 5) were immediately watertight and patent. All animals survived the 28-day study duration. Angiography revealed patent grafts with no aneurysm or stenosis (n = 5). Histologic examination revealed integration of the venous endothelium with the arterial adventitia. Conclusion. Photochemical tissue bonding creates an immediate strong, watertight vascular anastomosis that can withstand physiologic arterial pressure and remains patent at 28 days without the need for intraluminal suture.

Network-based assessment of HDAC6 activity predicts preclinical and clinical responses to the HDAC6 inhibitor ricolinostat in breast cancer.

Inhibiting individual histone deacetylase (HDAC) is emerging as well-tolerated anticancer strategy compared with pan-HDAC inhibitors. Through preclinical studies, we demonstrated that the sensitivity to the leading HDAC6 inhibitor (HDAC6i) ricolinstat can be predicted by a computational network-based algorithm (HDAC6 score). Analysis of ~3,000 human breast cancers (BCs) showed that ~30% of them could benefice from HDAC6i therapy. Thus, we designed a phase 1b dose-escalation clinical trial to evaluate the activity of ricolinostat plus nab-paclitaxel in patients with metastatic BC (MBC) (NCT02632071). Study results showed that the two agents can be safely combined, that clinical activity is identified in patients with HR+/HER2- disease and that the HDAC6 score has potential as predictive biomarker. Analysis of other tumor types also identified multiple cohorts with predicted sensitivity to HDAC6i's. Mechanistically, we have linked the anticancer activity of HDAC6i's to their ability to induce c-Myc hyperacetylation (ac-K148) promoting its proteasome-mediated degradation in sensitive cancer cells.

A Photosealed Cap Prevents Disorganized Axonal Regeneration and Neuroma following Nerve Transection in Rats.

Neuroma is a common sequela of traumatic peripheral nerve injury that can result in pain and decreased quality of life for patients. Neuromas result from axonal outgrowth in an attempt to reestablish continuity with the disrupted distal nerve end. Photosealing is a light-activated technique whereby tissues can be securely isolated in a strong and secure manner. This study investigated whether photosealing of autologous vein and crosslinked human amniotic membrane (xHAM) to cap the proximal stump of transected sciatic nerve would prevent disorganized axonal regeneration and neuroma in a rat model. Methods: The right sciatic nerve of Lewis rats (n = 27, 300-350 g) was transected 1 cm proximal to the trifurcation. Animals were randomized to one of three groups (n = 9): no further intervention (Group 1), photosealing with xHAM (Group 2), or photosealing with vein (Group 3). After 60 days, rats were euthanized and their right hindlimbs were re-explored for evidence of disorganized axonal regeneration and/or bulbous neuroma. Results: All untreated control animals were found to have protruding nerve fibers, often invading the adjacent muscle, and 33% of these control animals exhibited a bulbous neuroma. Photosealing with xHAM successfully capped 100% of nerves, with no observable axonal outgrowth. Photosealing with vein prevented axonal outgrowth in eight of nine nerves. No bulbous neuroma was found in any photosealed nerves. Conclusion: Nerve capping with photosealed xHAM or autologous vein can prevent axonal outgrowth in transected nerves, therefore decreasing the likelihood of symptomatic neuroma formation following nerve transection injury or surgical intervention.

Light-activated photosealing with human amniotic membrane strengthens bowel anastomosis in a hypotensive, trauma-relevant swine model.

BACKGROUND: Gastrointestinal anastomotic leakage is a dreaded complication despite advancements in surgical technique. Photochemical tissue bonding (PTB) is a method of sealing tissue surfaces utilizing photoactive dye. We evaluated if crosslinked human amniotic membrane (xHAM) photosealed over the enteroenterostomy would augment anastomotic strength in a trauma-relevant swine hemorrhagic shock model. METHODS: Yorkshire swine (40-45 kg, n = 14) underwent midline laparotomy and sharp transection of the small intestine 120 cm proximal to the ileocecal fold. Immediately following intestinal transection, a controlled arterial bleed was performed to reach hemorrhagic shock. Intestinal repair was performed after 60 minutes and autotransfusion of the withdrawn blood was performed for resuscitation. Animals were randomized to small intestinal anastomosis by one of the following methods (seven per group): suture repair (SR), or SR with PTB augmentation. Animals were euthanized at postoperative Day 28 and burst pressure (BP) strength testing was performed on all excised specimens. RESULTS: Mean BP for SR, PTB, and native tissue groups were 229 ± 40, 282 ± 21, and 282 ± 47 mmHg, respectively, with the SR group statistically significantly different on analysis of variance (p = 0.02). Post-hoc Tukey all-pairs comparison demonstrated a statistically significant difference in burst pressure strength between the SR only and the PTB group (p = 0.04). All specimens in SR group ruptured at the anastomosis upon burst pressure testing, while all specimens in the PTB group ruptured at least 2.5 cm from the anastomosis. CONCLUSION: Photosealing with xHAM significantly augments the strength of small intestinal anastomosis performed in a trauma porcine model.

A comparison of nurses' and physicians' perception of cancer treatment burden based on reported adverse events.

BACKGROUND: Cancer treatments are associated with a multitude of adverse events (AEs). While both nurses and physicians are involved in patient care delivery and AE assessment, very few studies have examined the differences between nurses' and physicians' reporting and perception of AEs. An approach was recently proposed to assess treatment burden based on reported AEs from the physician's perspective. In this paper, we use this approach to evaluate nurses' perception of burden, and compare nurses' and physicians' assessment of the overall and relative burden of AEs. METHODS: AE records for 334 cancer patients from a randomized clinical trial conducted by the SWOG Cancer Research Network were evaluated by 14 nurses at Columbia University Medical Center. Two nurses were randomly selected to assign a burden score from 0 to 10 based on their impression of the global burden of the captured AEs. These nurses did not interact directly with the patients. Scores were compared to previously obtained physicians scores using paired T-test and Kappa statistic. Severity scores for individual AEs were obtained using mixed-effects models with nurses assessments, and were qualitatively compared to physicians'. RESULTS: Given the same AEs, nurses' and physicians' perception of the burden of AEs differed. While nurses generally perceived the overall burden of AEs to be only slightly worse compared to physicians (mean average VAS score of 5.44 versus 5.14), there was poor agreement in the perception of AEs that were in mild to severe range. The percent agreement for a moderate or worse AE was 64% with a Kappa of 0.34. Nurses also assigned higher severity scores to symptomatic AEs compared to physicians (p < 0.05), such as gastrointestinal (4.77 versus 4.14), hemorrhage (5.07 versus 4.14), and pain (5.17 versus 4.14). CONCLUSIONS: These differences in the perception of burden of AEs can lead to different treatment decisions and symptom management strategies. Thus, having provider consistency, training, or a collaborative approach in follow-up care between nurses and physicians is important to ensure continuity in care delivery. Moreover, estimating overall burden from both physicians' and nurses' perspective, and comparing them may be useful for deciding when collaborations are warranted.