Retrograde Carotid Stenting Using Newly Released Venous Stent for Cerebral Malperfusion in Type A Aortic Dissection.

Stanford Type A aortic dissections (TAAD) should be considered for repair, given the involvement of branch vessels which can result in malperfusion, specifically cerebral malperfusion secondary to dissection of the innominate and carotid arteries. This is a case report with a focus on four patients presenting with both acute and chronic symptomatic TAAD, with extension into the innominate and common carotid arteries. In all four cases, the decision to intervene utilizing a hybrid endovascular approach was made to increase perfusion to the brain and alleviate symptoms. Through the use of retrograde carotid stenting utilizing both the VICI venous stent (Boston Scientific, Marlborough, MA) and Abre self-expanding Nitinol stent (Medtronic, Minneapolis, MN) we obtained good results, specifically absence of symptoms and return to normal function of the patients.

Extracorporeal life support for cardiogenic shock during pregnancy and postpartum: a single center experience.

BACKGROUND: The use of veno-arterial extracorporeal membrane oxygenation (VA ECMO) for cardiogenic shock in pregnant and postpartum patients remains limited by concerns of bleeding, hemolysis, and fetal risks. This case series examines the underlying characteristics and management strategies for this high-risk population. METHODS: All pregnant and post-partum patients who underwent VA ECMO in the cardiovascular intensive care unit between January 1, 2016 and November 1, 2019, were included in this retrospective study. Management of maternal and fetal O2 delivery, left ventricular (LV) unloading, anticoagulation, and ECMO circuit characteristics were evaluated. RESULTS: Five patients required veno-arterial ECMO for restoration of systemic perfusion. Three patients developed peripartum cardiomyopathy, one septic cardiomyopathy, and one acute right ventricular (RV) failure. The median age was 30.6 years, with median gestational age in pregnant patients of 31 weeks. Maternal and fetal survival to discharge was 80%. Bleeding was the primary complication, with two patients requiring blood transfusions; one requiring interventional radiology (IR) embolization and the other requiring surgical intervention to control bleeding. One patient was successfully delivered on VA ECMO. No fetal complications were directly attributed to VA ECMO. CONCLUSIONS: VA ECMO can be employed successfully in obstetric patients with cardiogenic shock with appropriate patient selection. Further research is needed to determine if VA ECMO provides a survival advantage over traditional management strategies in this vulnerable population.

Management of large bore access complications in the era of trans-catheter aortic valve replacement.

OBJECTIVES: Trans-catheter aortic valve replacement is a commonplace procedure for patients with aortic valvular stenosis who are at a high risk for surgery, evidenced by the 34,892 trans-catheter aortic valve replacements performed in 2016. Trans-catheter aortic valve replacement's rate of major vascular complications with second-generation closure devices is 4.5% according to a meta-analysis of 10,822 patients. To manage those complications, percutaneous approaches to arterial repairs show shorter length of stay, higher rate of direct to home discharge and equivalent outcomes at long-term follow-up. This study's goal is to show that one center's vascular access strategy can decrease open repairs and improve patient outcomes. METHODS: Our team began accessing the mid-common femoral artery at least 1-2 cm proximal to the takeoff of the profunda femoris. This allowed an endovascular stent to be deployed if necessary via contralateral femoral access. We performed a completion angiogram following every trans-catheter aortic valve replacement to ensure no arterial complications. We conducted a retrospective review of a prospectively maintained database for all trans-catheter aortic valve replacement cases at a tertiary care center from 1 January 2016 to 30 June 2018. RESULTS: A total of 699 trans-catheter aortic valve replacement procedures were performed with 25/31 (80.6%) cases met inclusion criteria. An increase was noted in the number of stent procedures versus cutdown procedures over time (P < 0.001). A decrease was noted in the number of vascular surgery team activations following trans-catheter aortic valve replacement (P = 0.004). A non-significant trend was noted toward a shorter median length of stay for the stent group (P = 0.149). There was no increase in 30-day mortality rate (0.0% for both groups) or 30-day readmissions (4/15 (26.7%) for stents vs. 2/10 (20.0%) for open repairs; P > 0.999). CONCLUSIONS: This strategy is safe and feasible to implement and reduces the number of open repairs following trans-catheter aortic valve replacement, activation of surgical resources, and possibly the length of stay.

Overexpression, purification and biophysical characterisation of E. coli MerT.

Mercury resistance is the most widespread of all anti-microbial resistance occurring in a wide variety of Gram-negative and Gram-positive bacterial genera. The systems that are most studied and best understood are those encoded in mercury resistance (Mer) operons in Gram-negative bacteria. The mercury detoxification functions by the importation of highly toxic Hg(2+) into cytoplasm and enzymic reduction to volatile Hg(0). MerT is a small (13kDa) inner membrane protein involved in mercuric ion transport system. We have overexpressed recombinant 6His-tagged MerT from Escherichia coli in a native folded form and purified it to homogeneity in n-dodecyl-ß-d-maltopyranoside (DDM) by immobilized metal affinity chromatography (IMAC). Circular dichroism showed that the protein is largely α-helical. Size-exclusion chromatography (SEC) in a variety of detergents showed that the protein exists in a multiple of oligomeric states as also confirmed by SEC coupled with multiple-angle light scattering.

Pressure-induced gelatinization of starch in excess water.

High pressure processing is a promising non-thermal technology for the development of fresh-like, shelf-stable foods. The effect of high pressure on starch has been explored by many researchers using a wide range of techniques. In general, heat and pressure have similar effects: if sufficiently high, they both induce gelatinization of starch in excess water, resulting in a transition of the native granular structure to a starch paste or gel. However, there are significant differences in the structural and rheological properties between heated and pressurized starches. These differences offer benefits with respect to new product development. However, in order to implement high-pressure technology to starch and starch-containing products, a good understanding of the mechanism of pressure-induced gelatinization is necessary. Studies that are published in this area are reviewed, and the similarities and differences between starches gelatinized by pressure and by temperature are summarized.

A Novel Hybrid Approach to Management of KD: Role of Robotic Surgery.

The management of Kommerell's Diverticulum (KD) has been evolving from open repair to a hybrid of open and endovascular repair. While there is no consensus regarding the optimal strategy, the need for less invasive treatment with less morbidity early recovery, and improved quality of life is a common goal for both the patient and the provider.

Mid-Term Results of Treating Kommerell's Diverticulum and Aberrant Subclavian Artery Anomalies Using a Patient-Centered Team Approach.

INTRODUCTION: The management of Kommerell's Diverticulum (KD) has evolved from open surgical resection and graft replacement of the aorta, to endovascular repair in asymptomatic patients due to its recognized possible sequelae - aortic rupture and dissection. Despite these technical advances, standard indications for intervention and treatment algorithms remain unclear. We will present our single-center experience in the treatment of KD, supporting a multidisciplinary endovascular-first approach. METHODS: All patients who underwent thoracic endovascular aortic repair (TEVAR) for KD between 2017 and 2020 were retrospectively identified from a prospectively maintained institutional surgery database. Chart review was used to characterize presenting symptoms, interventions, technical results, and complications. Revascularization was performed using carotid-axillary bypass. Routine endovascular subclavian artery occlusion was employed to eliminate retrograde diverticulum perfusion and avoid open ligation. RESULTS: 8 patients were identified, including 6 females and 2 males between the ages of 44-76. Patients presented with dysphagia (n = 3), acute embolic stroke (n = 1), transient ischemic attack (TIA) (n = 1), upper extremity embolization (n = 1), and acute type B aortic dissection (n = 1). One patient had a prior incomplete open repair that was successfully treated endovascularly. Another patient had a mediastinal neoplasm infiltrating an incidental aberrant subclavian artery and KD. All cases had symptomatic improvement and successful endovascular repair as demonstrated on post-operative imaging. Perioperative complications included percutaneous access site pseudoaneurysm (n = 2), stroke (n = 1), and subclavian artery rupture immediately recognized and treated (n = 1). There was no perioperative mortality. CONCLUSION: Endovascular techniques have resulted in technical success and symptomatic improvement for KD without open thoracotomy or sternotomy. Significant rates of endovascular complications and paucity of long-term durability data should be considered. Until formal criteria for repair are established, early application of TEVAR using a consistent multi-specialty approach may mitigate the risk of unpredictable aortic complications in these patients while avoiding the accepted morbidity and mortality of open surgery.

The cystic fibrosis transmembrane conductance regulator (CFTR): three-dimensional structure and localization of a channel gate.

Cystic fibrosis affects about 1 in 2500 live births and involves loss of transmembrane chloride flux due to a lack of a membrane protein channel termed the cystic fibrosis transmembrane conductance regulator (CFTR). We have studied CFTR structure by electron crystallography. The data were compared with existing structures of other ATP-binding cassette transporters. The protein was crystallized in the outward facing state and resembled the well characterized Sav1866 transporter. We identified regions in the CFTR map, not accounted for by Sav1866, which were potential locations for the regulatory region as well as the channel gate. In this analysis, we were aided by the fact that the unit cell was composed of two molecules not related by crystallographic symmetry. We also identified regions in the fitted Sav1866 model that were missing from the map, hence regions that were either disordered in CFTR or differently organized compared with Sav1866. Apart from the N and C termini, this indicated that in CFTR, the cytoplasmic end of transmembrane helix 5/11 and its associated loop could be partly disordered (or alternatively located).

Self-directed assembly and clustering of the cytoplasmic domains of inwardly rectifying Kir2.1 potassium channels on association with PSD-95.

The interaction of the extra-membranous domain of tetrameric inwardly rectifying Kir2.1 ion channels (Kir2.1NC(4)) with the membrane associated guanylate kinase protein PSD-95 has been studied using Transmission Electron Microscopy in negative stain. Three types of complexes were observed in electron micrographs corresponding to a 1:1 complex, a large self-enclosed tetrad complex and extended chains of linked channel domains. Using models derived from small angle X-ray scattering experiments in which high resolution structures from X-ray crystallographic and Nuclear Magnetic Resonance studies are positioned, the envelopes from single particle analysis can be resolved as a Kir2.1NC(4):PSD-95 complex and a tetrad of this unit (Kir2.1NC(4):PSD-95)(4). The tetrad complex shows the close association of the Kir2.1 cytoplasmic domains and the influence of PSD-95 mediated self-assembly on the clustering of these channels.

Targeted regional injection of biocomposite microspheres alters post-myocardial infarction remodeling and matrix proteolytic pathways.

BACKGROUND: Although localized delivery of biocomposite materials, such as calcium hydroxyapatite (CHAM), have been demonstrated to potentially attenuate adverse left ventricular (LV) remodeling after myocardial infarction (MI), the underlying biological mechanisms for this effect remain unclear. This study tested the hypothesis that targeted CHAM injections would alter proteolytic pathways (matrix metalloproteinases [MMPs] and tissue inhibitors of MMPs [TIMPs]) and would be associated with parameters of post-MI LV remodeling. METHODS AND RESULTS: MI was induced in adult sheep followed by 20 targeted injections of a total volume of 1.3 mL (n=6) or 2.6 mL of CHAM (n=5) or saline (n=13) and LV end-diastolic volume (EDV) and MMP/TIMP profiles in the MI region were measured at 8 weeks after MI. LV EDV decreased with 2.6 mL CHAM versus MI only (105.4 ± 7.5 versus 80.6 ± 4.2 respectively, P<0.05) but not with 1.3 mL CHAM (94.5 ± 5.0, P=0.32). However, MI thickness increased by 2-fold in both CHAM groups compared with MI only (P<0.05). MMP-13 increased 40-fold in the MI only group (P<0.05) but fell by >6-fold in both CHAM groups (P<0.05). MMP-7 increased approximately 1.5-fold in the MI only group (P<0.05) but decreased to referent control values in both CHAM groups in the MI region (P<0.05). Collagen content was reduced by approximately 30% in the CHAM groups compared with MI only (P<0.05). CONCLUSIONS: Differential effects on LV remodeling and MMP/TIMP profiles occurred with CHAM. Thus, targeted injection of a biocomposite material can favorably affect the post-MI remodeling process and therefore holds promise as a treatment strategy in and of itself, or as a matrix with potentially synergistic effects with localized pharmacological or cellular therapies.

The impact of salt reduction in bread: a review.

The dietary intake of sodium chloride has increased considerably over the last few decades due to changes in the human diet. This higher intake has been linked to a number of diseases including hypertension and other cardiovascular diseases. Numerous international health agencies, as well as the food industry, have now recommended a salt intake level of about 5-6 g daily, approximately half the average current daily intake level. Cereal products, and in particular bread, are a major source of salt in the diet. Therefore, any reduction in the level of salt in bread would have a major impact on global health. However, salt is a critical ingredient in bread production, and its reduction can have a deleterious effect on the production process. This includes an impact on dough handling, as well as final bread quality characteristics, including shelf-life, bread volume, and sensory characteristics, all deviating from the expectations of bakers and consumers. This review describes the effect of salt reduction during bread production and the resulting problems, both technological and qualitative, as well as evaluating some techniques commonly used to replace sodium chloride.

The effect of sourdough and calcium propionate on the microbial shelf-life of salt reduced bread.

The consumption of low-salt bread represents an efficient way to improve public health by decreasing cardiovascular health issues related to increased intakes of sodium chloride (NaCl). The reduction of NaCl influences the bread quality characteristics, in particular the shelf-life. Calcium propionate (CP) is commonly used in bread as an antifungal agent. Alternatively, sourdough can be used as a natural preservative. This work addresses the feasibility of NaCl reduction in wheat bread focussing on shelf-life and the compensation using sourdough as well as chemical preservatives. The impact of NaCl reduction and the addition of preservative agents in conjunction with different NaCl concentrations on the shelf-life of bread were tested under 'environmental' conditions in a bakery as well as using challenge tests against selected fungi. The challenge tests were performed using fungi commonly found in the bakery environment such as Penicillium expansum, Fusarium culmorum and Aspergillus niger. NaCl reduction decreased the shelf-life by 1-2 days. The addition of sourdough with antifungal activity prolonged the shelf-life to 12-14 days whereas the addition of 0.3 % calcium propionate prolonged the shelf-life to 10-12 days only. The fungal challenge tests revealed differences in the determined shelf-life between the different fungi based on their resistance. Similar antifungal performance was observed in sourdough breads and calcium propionate breads when tested against the different indicator moulds. The findings of this study indicate that addition of sourdough fermented using a specifically selected antifungal Lactobacillus amylovorus DSM 19280 can replace the chemical preservative calcium propionate addition and compensate for the reduced level and, therefore, guarantee the product safety of low-salt bread.

Endovascular Repair of an Iatrogenic Pulmonary Artery Pseudoaneurysm.

Pulmonary pseudoaneurysms have various causes and typically arise from the main pulmonary artery. Surgical and endovascular options may be considered for treatment. We report the case of a man with a pseudoaneurysm arising from the right pulmonary artery, treated with a septal occlusion device and percutaneous thrombin injection. (Level of Difficulty: Advanced.).

Endovascular Repair of Symptomatic Right Subclavian and Innominate Artery Aneurysms Arising From a "Bovine Arch" in a Patient With a "Hostile" Chest.

Symptomatic aneurysms of the innominate and subclavian arteries are rare and pose unique challenges for endovascular repair particularly in a patient with a "bovine" arch. Previous publications have described back table modifications of standard iliac endografts to conform to the innominate artery for exclusion of the lesion. Others have proposed extra-anatomic bypass or carotid-subclavian transposition with occlusion of the innominate artery. We were unable to find a report of repair when aneurysms of the innominate and subclavian arteries were in continuity. We present such a case of endovascular repair using commercially available endografts without compromise of the left common carotid artery origin as this patient had a "bovine" arch. Surgeons will benefit from adding this endovascular option to their "tool box" when confronted with such a challenging clinical scenario.

Preclosure technique versus arterial cutdown after percutaneous cannulation for venoarterial extracorporeal membrane oxygenation.

BACKGROUND: Arteriotomy repair through the preclosure technique during elective arterial access procedures is well documented. Outcomes associated with application of this technique to the removal of arterial access cannulas in patients undergoing urgent venoarterial extracorporeal membrane oxygenation (VA-ECMO) have not previously been reported. METHODS: We reviewed the records of consecutive patients who required VA-ECMO for cardiogenic shock. Patients were compared by use of the preclosure device (Perclose ProGlide Suture-Mediated Closure System; Abbott Vascular, Abbott Park, Ill) at time of VA-ECMO cannulation. The rate of limb complications (composite of limb ischemia, infection, and site necrosis) and secondary end points of bleeding events, pseudoaneurysm, distal part embolization, and intensive care unit length of stay after decannulation were compared between the groups. RESULTS: Ninety-nine consecutive patients managed with VA-ECMO were identified and the preclosure device was utilized in 51 of these patients. Preclosure device failure occurred in 5 instances (9.8%) and was successfully managed with surgical repair in 4 cases and endovascular intervention in another. Use of the preclosure device was associated with both fewer limb complications (odds ratio, 0.19; 95% confidence interval, 0.03-0.78) and bleeding events (odds ratio, 0.21; 95% confidence interval, 0.04-0.89). Pseudoaneurysm (n = 0) and distal part embolization (n = 1) were infrequently encountered in the cohort and no difference in intensive care unit length of stay after decannulation was noted between the groups. CONCLUSIONS: In this cohort, use of the preclosure technique in weaning from VA-ECMO was technically feasible, safe, and associated with an approximate 80% lower likelihood of limb complications and bleeding events compared with surgical removal.

Coprocytobiology: A Technical Review of Cytological Colorectal Cancer Screening in Fecal Samples.

This review discusses the field of coprocytobiology, defined as a combined method of cell preservation, isolation, and cytology, which has applications to the investigation of noninvasive fecal screening for colorectal cancer. In the decade since the field was last reviewed, cell isolation has progressed rapidly via the development of technologies such as microfluidic and magnetic cell sorting. The landscape of cytology has also advanced in this time with the emergence of novel cytological methods and cell preservation strategies. Previous reviews present an outdated and incomplete view of coprocytobiology, summarizing a limited number of early publications, ignoring the principle of cell preservation and focusing on a single method of isolation rather than the field as a whole. In contrast to these publications, this review presents an updated, comprehensive, and unbiased representation of the technical aspects of coprocytobiology and provides unique insight into the common methodological pitfalls, best practice, and future directions of cytological screening for colorectal cancer.This review discusses the field of coprocytobiology, defined as a combined method of cell preservation, isolation, and cytology, which has applications to the investigation of noninvasive fecal screening for colorectal cancer. In the decade since the field was last reviewed, cell isolation has progressed rapidly via the development of technologies such as microfluidic and magnetic cell sorting. The landscape of cytology has also advanced in this time with the emergence of novel cytological methods and cell preservation strategies. Previous reviews present an outdated and incomplete view of coprocytobiology, summarizing a limited number of early publications, ignoring the principle of cell preservation and focusing on a single method of isolation rather than the field as a whole. In contrast to these publications, this review presents an updated, comprehensive, and unbiased representation of the technical aspects of coprocytobiology and provides unique insight into the common methodological pitfalls, best practice, and future directions of cytological screening for colorectal cancer.

"You'd be better off to do the keyhole and make a good job of it" a qualitative study of the beliefs and treatment expectations of patients attending secondary care with degenerative meniscal tears.

BACKGROUND: Current clinical practice guidelines for degenerative meniscal tears recommend conservative management yet patients are frequently referred to the consultant orthopaedic surgeon despite a lack of evidence for the use of arthroscopy. OBJECTIVES: To explore the beliefs about their condition and treatment expectations of patients referred to a secondary care orthopaedic clinic with a degenerative meniscal tear. DESIGN AND METHODS: Design and MethodsThis qualitative study involved ten patients who participated in semi-structured telephone interviews. Data were subjected to thematic analysis and findings were reported in accordance with the Consolidated Criteria for Reporting Qualitative Studies. RESULTS: Analysis identified five themes. Participants described beliefs, strongly influenced by magnetic resonance imaging (MRI) results, that damaged structures were causing their knee problems ("The meniscus is busted"), and expected their knee problems to inevitably worsen over time ("It's only going to get worse"). Participants were hopeful the orthopaedic consultation would clarify their problem and lead to a subsequent definitive intervention ("Hopefully they will give me answers"). Most participants viewed surgery as "the quick and straightforward solution" necessary to repair faulty cartilage. Exercise was not seen as compatible with the recovery process by most ("Would I make it worse?"). CONCLUSIONS: How participants understand their knee problem contributes to surgical expectations and perceptions that it is not amenable to conservative management. Findings suggest a need to educate both patients and primary care clinicians about the safety and efficacy of exercise as first-line therapy for degenerative meniscal tears. The negative role of MRI in promoting surgical expectations needs further consideration.