surgical-perfusion-isolation-porcine-pancreas-for-islet

Surgical Perfusion and Isolation of the Porcine Pancreas for Islet Isolation

Pancreatic islet transplantation is an emerging treatment for type I diabetes; however, it is limited by donor matching and availability. Porcine islet ...

Washington University School of Medicine

During the coronavirus disease 2019 (COVID-19) pandemic, providers and patients must engage in shared decision making to ensure that the benefit of early intervention for muscle-invasive bladder cancer exceeds the risk of contracting COVID-19 in the clinical setting. It is unknown whether treatment delays for patients eligible for curative chemoradiation (CRT) compromise long-term outcomes.

Management of Muscle-Invasive Bladder Cancer During a Pandemic: Impact of Treatment Delay on Survival Outcomes for Patients Treated With Definitive Concurrent Chemoradiotherapy.

There are limited data on the role of local therapy for metastatic urothelial carcinoma of the bladder (mUC). In this retrospective cohort analysis, we queried the National Cancer Data Base for patients with newly diagnosed mUC (cT1-4 N0-3 M1). Overall survival (OS) was compared between treatment with chemotherapy (CT) alone (n = 4122) and CT plus bladder-directed radiation therapy (CT + RT; n = 337). Multivariable Cox proportional-hazards analyses and matching and landmark analyses were performed. CT + RT was independently associated with better OS (hazard ratio 0.70, 95% confidence interval 0.62-0.79; p < 0.0001) and this result persisted in matched and landmark analyses. These findings are hypothesis-generating and limited by inherent confounding factors; however, a prospective trial evaluating the impact of bladder RT in mUC is warranted. PATIENT SUMMARY: For patients with bladder cancer that has already spread to other parts of the body, it is unclear if radiation therapy directed at the primary bladder tumor would provide any improvement in survival. In this study, we found that aggressive radiation therapy directed at the bladder combined with chemotherapy may provide a survival benefit in some patients with metastatic bladder cancer compared to chemotherapy alone.

Association Between Local Radiation Therapy to the Primary Bladder Tumor and Overall Survival for Patients with Metastatic Urothelial Cancer Receiving Systemic Chemotherapy.

The PEVAR Trial demonstrated that compared to open femoral exposure, elective percutaneous endovascular AAA repair (ePEVAR) is associated with decreased perioperative morbidity and access site complications. We hypothesized that PEVAR for ruptured AAA (rPEVAR) may also improve perioperative morbidity compared to open femoral exposure (rEVAR). There are currently no reports that evaluate the utility and outcomes of rPEVAR.

Totally percutaneous endovascular repair for ruptured abdominal aortic aneurysms.

 Coronavirus disease 2019 (COVID-19) is associated with provoked thrombo-inflammatory responses. Early in the COVID-19 pandemic this was thought to contribute to hypercoagulability and multi-organ system complications in infected patients. Limited studies have evaluated the impact of therapeutic anti-coagulation therapy (AC) in alleviate these risks in COVID-19 positive patients. Our study aimed to investigate whether long-term therapeutic AC can decrease the risk of multi-organ system complications (MOSC) including stroke, limb ischemia, gastrointestinal (GI) bleeding, in-hospital and intensive care unit death in COVID-19 positive patients during the early phase of the pandemic in the United States.  A retrospective analysis was conducted of all COVID-19 positive United States Veterans between March 2020 and October 2020. Patients receiving continuous therapeutic AC for a least 30 days prior to or after their initial COVID-19 positive test were assigned to the AC group. Patients who did not receive AC were included in a control group. We analyzed the primary study outcome of MOSC between the AC and control groups using binary logistic regression analysis (Odd-Ratio; OR).  We identified 48,066 COVID-19 patients, of them 879 (1.8%) were receiving continuous therapeutic AC. The AC cohort had significantly worse comorbidities than the control group. On the adjusted binary logistic regression model, therapeutic AC significantly decreased in-hospital mortality rate (OR; 0.67,  0.04), despite a higher incidence of GI bleeding (OR; 4.00,  0.02). However, therapeutic AC did not significantly reduce other adverse events.  AC therapy reduced in-hospital death early in the COVID-19 pandemic among patients who were hospitalized with the infection. However, it did not decrease the risk of MOSC. Additional trials are needed to determine the effectiveness of AC in preventing complications associated with ongoing emerging strains of the COVID-19 virus.

Chronic Anti-Coagulation Therapy Reduced Mortality In Patients With High Cardiovascular Risk Early In COVID-19 Pandemic.

Coronavirus disease 2019 (COVID-19) is associated with provoked thrombo-inflammatory responses. Early in the COVID-19 pandemic this was thought to contribute to hypercoagulability and multi-organ system complications in infected patients. Limited studies have evaluated the impact of therapeutic anti-coagulation therapy (AC) in alleviating these risks in COVID-19 positive patients. Our study aimed to investigate whether long-term therapeutic AC can decrease the risk of multi-organ system complications (MOSC) including stroke, limb ischemia, gastrointestinal (GI) bleeding, in-hospital and intensive care unit death in COVID-19 positive patients hospitalized during the early phase of the pandemic in the United States.

Chronic anti-coagulation therapy reduced mortality in patients with high cardiovascular risk early in COVID-19 pandemic.

Abdominal aortic aneurysms (AAAs) are prevelant with aging, and AAA rupture is associated with high mortality. There is currently no effective medical therapy for AAA rupture. Previous work demonstrated that the monocyte chemoattractant protein (MCP-1) / C-C chemokine receptor type 2 (CCR2) axis critically regulates AAA inflammation, matrix-metalloproteinase (MMP) production, and extracellular matrix (ECM) stability. Here we similarly observed that  mice have significantly reduced AAA expansion and rupture. We therefore hypothesized that a dietary modulation of the CCR2 axis may therapeutically impact AAA risk of rupture. Since ketone bodies (KBs) can trigger repair mechanisms in response to inflammation, we specifically evaluated whether systemic ketosis  can reduce CCR2 and AAA progression. Male Sprague-Dawley rats underwent surgical AAA formation using porcine pancreatic elastase (PPE), and received daily β-aminopropionitrile (BAPN) to promote AAA rupture. Animals with AAAs received either a standard diet (SD), ketogenic diet (KD), or exogenous KBs (EKB). Animals recieving KD and EKB reached a state of ketosis, and had significant reduction in AAA expansion and incidence of rupture. Ketosis also led to significantly reduced aortic CCR2 content, improved MMP balance, and reduced ECM degradation. In summary, this study demonstrates that ketosis plays a crucial role in AAA pathobiology, and provides the impetus for future clinical studies investigating the potential benefit of ketosis for prevention of AAA expansion and rupture.

Ketosis Prevents Abdominal Aortic Aneurysm Rupture Through C-C Chemokine Receptor Type 2 Downregulation and Enhanced MMP Balance.

A comprehensive review of the current literature was conducted to summarize the potential therapeutic and management roles of ketogenic diet (KD) for cardiovascular disease (CVD).

Impact of ketogenic diet on cardiovascular disease.

Abdominal aortic aneurysms (AAAs) are prevalent with aging, and AAA rupture is associated with increased mortality. There is currently no effective medical therapy to prevent AAA rupture. The monocyte chemoattractant protein (MCP-1)/C-C chemokine receptor type 2 (CCR2) axis critically regulates AAA inflammation, matrix-metalloproteinase (MMP) production, and extracellular matrix (ECM) stability. We therefore hypothesized that a diet intervention that can modulate CCR2 axis may therapeutically impact AAA risk of rupture. Since ketone bodies (KBs) can trigger repair mechanisms in response to inflammation, we evaluated whether systemic ketosis in vivo could reduce CCR2 and AAA progression. Male Sprague-Dawley rats underwent surgical AAA formation using porcine pancreatic elastase and received daily β-aminopropionitrile to promote AAA rupture. Rats with AAAs received either a standard diet, ketogenic diet (KD), or exogenous KBs (EKB). Rats receiving KD and EKB reached a state of ketosis and had significant reduction in AAA expansion and incidence of rupture. Ketosis also led to significantly reduced aortic CCR2 content, improved MMP balance, and reduced ECM degradation. Consistent with these findings, we also observed that Ccr2-/- mice have significantly reduced AAA expansion and rupture. In summary, this study demonstrates that CCR2 is essential for AAA expansion, and that its modulation with ketosis can reduce AAA pathology. This provides an impetus for future clinical studies that will evaluate the impact of ketosis on human AAA disease.

Ketosis prevents abdominal aortic aneurysm rupture through C-C chemokine receptor type 2 downregulation and enhanced extracellular matrix balance.

The study establishes a rapid, technically straightforward, and reproducible porcine large animal model for acute iliocaval deep vein thrombosis (DVT). The procedure can be performed with basic endovascular skillsets. With its procedural efficiency and consistency, the platform is promising for comparative in vivo testing of venous thrombectomy devices in a living host, and for future verification and validation studies to determine efficacy of novel thrombectomy devices relative to predicates.

In Vivo Porcine Model of Acute Iliocaval Deep Vein Thrombosis.

A vascular anastomosis is a critical surgical skill that involves connecting blood vessels. Traditional handsewn techniques can be challenging and resource intensive. To address these issues, we have developed a unique sutureless anastomotic device called Vaso-Lock. This intraluminal device connects free vascular ends using anchors to maintain traction and enable a rapid anastomosis. We tested the anastomotic capability of Vaso-Locks in a pig common carotid-internal jugular arteriovenous model. The use of Vaso-Lock allowed us to accomplish this procedure in less than 10 min, in contrast to the approximately 40 min required for a handsewn anastomosis. The Vaso-Lock effectively maintained patency for at least 6 weeks without causing significant tissue damage. Histological analysis revealed that the device was successfully incorporated into the arterial wall, promoting a natural healing process. Additionally, organ evaluations indicated no adverse effects from using the Vaso-Lock. Our findings support the safety and effectiveness of the Vaso-Lock for arteriovenous anastomosis in pigs, with potential applicability for translation to humans. Our novel sutureless device has the potential to advance surgical practice and improve patient outcomes.

Article	Year
Management of Muscle-Invasive Bladder Cancer During a Pandemic: Impact of Treatment Delay on Survival Outcomes for Patients Treated With Definitive Concurrent Chemoradiotherapy. Clinical genitourinary cancer\| PubMed ID: 33187904	2021
Association Between Local Radiation Therapy to the Primary Bladder Tumor and Overall Survival for Patients with Metastatic Urothelial Cancer Receiving Systemic Chemotherapy. European urology oncology\| PubMed ID: 35249864	2022
Totally percutaneous endovascular repair for ruptured abdominal aortic aneurysms. Frontiers in surgery\| PubMed ID: 36338637	2022
Chronic Anti-Coagulation Therapy Reduced Mortality In Patients With High Cardiovascular Risk Early In COVID-19 Pandemic. Research square\| PubMed ID: 36415466	2022
Chronic anti-coagulation therapy reduced mortality in patients with high cardiovascular risk early in COVID-19 pandemic. Thrombosis journal\| PubMed ID: 36717941	2023
Ketosis Prevents Abdominal Aortic Aneurysm Rupture Through C-C Chemokine Receptor Type 2 Downregulation and Enhanced MMP Balance. Research square\| PubMed ID: 37461581	2023
Impact of ketogenic diet on cardiovascular disease. Nutrition reviews\| PubMed ID: 38109885	2023
Ketosis prevents abdominal aortic aneurysm rupture through C-C chemokine receptor type 2 downregulation and enhanced extracellular matrix balance. Scientific reports\| PubMed ID: 38228786	2024
In Vivo Porcine Model of Acute Iliocaval Deep Vein Thrombosis. Journal of endovascular therapy : an official journal of the International Society of Endovascular Specialists\| PubMed ID: 38357736	2024
Vaso-Lock for sutureless anastomosis in a pig arteriovenous loop model. Biomaterials\| PubMed ID: 38574456	2024

Mohamed Zaghloul

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