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71.

Objectives

We describe the Canadian results of the Ascyrus Medical Dissection Stent (AMDS), a novel partially uncovered aortic arch hybrid graft implanted antegrade during hypothermic circulatory arrest to promote true lumen expansion and enhance aortic remodeling.

Methods

From March 2017 to February 2018, 16 consecutive patients (66 ± 12 years; 38% female) presented with acute type A aortic dissections and underwent emergent surgical aortic repair with AMDS implantation. All patients presented with DeBakey I aortic dissection, with evidence of malperfusion in 50% (n = 8) of patients. All cases were performed under hypothermic circulatory arrest with an additional average duration for AMDS implantation time of 2.1 minutes.

Results

All 16 device implantations were successful. Overall 30-day mortality was 6.3% (n = 1) and stroke occurred in 6.3% (n = 1) of cases. There was no incidence of device-related aortic injury or aortic arch branch vessel occlusion. During the follow-up period, 12 patients had completed at least 1 postoperative computed tomography scan. At initial follow-up computed tomography scan, complete or partial thrombosis, and remodeling of the aortic arch occurred in 91.7% of cases (n = 11/12) and in the proximal descending thoracic aorta, complete or partial thrombosis, and remodeling occurred in 91.7% (n = 11/12).

Conclusions

Preliminary results suggest that the AMDS is a safe, feasible and reproducible adjunct to current surgical approaches for acute DeBakey I aortic dissection repair. Further, the AMDS manages malperfusion and promotes early positive remodeling in the aortic arch and distal dissected segments, with favorable FL closure rates at follow-up. Ongoing follow-up will provide additional insight into the long-term effects of the AMDS.  相似文献   
72.
73.
74.
ObjectiveThe aim of this study was to assess the effect of topical tranexamic acid on blood loss and transfusion rates in acetabular fracture surgery.MethodsThe medical records of 61 patients who underwent open reduction and internal fixation for acetabular fracture between 2012 and 2015 were retrospectively reviewed. The patients were divided into two groups: Group I consisted of 31 patients (19 men and 12 women, mean age: 52 ± 19 years) who received intraoperatively a topical tranexamic acid solution of 3 g and Group 2 consisted of 30 control patients (17 men and 13 women, mean age: 48 ± 24 years) who received only 0.9% saline solution. The groups were compared based on their intraoperative blood loss, Postoperative drain output at 24 and 48 h, and postoperative hemoglobin levels, and transfusion rates.ResultsThe mean intraoperative blood loss was 410 ± 100 ml in Group 1, compared to 570 ml ± 160 ml of the control group (p < 0.05). The postoperative drain output after 24 h was 210 ± 70 ml in Group 1 compared to 330 ± 90 ml of the control group (p < 0.05). The drain output at 48 h was (50 ± 20 ml) in group 1 compared to 90 ± 40 ml of the control group (p < 0.05). The transfusion rate was significantly low group 1 (42%) than the control group (97%). Hemoglobin drop was again significantly less in tranexamic acid group (2.1 ± 1.1) than the control group (3.2 ± 1.3). The nadir postoperative hemoglobin was higher in the Group 1 (10.4 ± 1.5) than the control group (9.2 ± 1.3).ConclusionTopical administration of tranexamic acid reduces intraoperative and postoperative blood loss in acetabular fracture surgery, decreasing transfusion rates.Level of EvidenceLevel III, Therapeutic Study.  相似文献   
75.
76.
Exercise intolerance is the cardinal symptom of heart failure (HF) and is of crucial relevance, because it is associated with a poor quality of life and increased mortality. While impaired cardiac reserve is considered to be central in HF, reduced exercise and functional capacity are the result of key patient characteristics and multisystem dysfunction, including aging, impaired pulmonary reserve, as well as peripheral and respiratory skeletal muscle dysfunction. We herein review the different modalities to quantify exercise intolerance, the pathophysiology of HF, and comorbid conditions as they lead to reductions in exercise and functional capacity, highlighting the fact that distinct causes may coexist and variably contribute to exercise intolerance in patients with HF.  相似文献   
77.
Type 2 diabetes mellitus (T2DM) is a complicated metabolic disease and has become one of the significant medical problems worldwide. Researchers aim to provide fine-tuned treatment for T2DM with minimal exposed side effects. Nutraceuticals are compounds or materials and emerging evidence suggests that the use of nutraceuticals has recently been recognized as a promising option for the prevention and management of T2DM, such as probiotics and prebiotics, Vitamin D, n-3 long-chain polyunsaturated fatty acids, and Plant-derived nutraceuticals. This review attempts to show the most popular nutraceuticals and review their effects and possible mechanisms in the prevention or glycemic control of T2DM.  相似文献   
78.
Lipid nanoparticles (LNPs) are becoming popular as a means of delivering therapeutics, including those based on nucleic acids and mRNA. The mRNA-based coronavirus disease 2019 vaccines are perfect examples to highlight the role played by drug delivery systems in advancing human health. The fundamentals of LNPs for the delivery of nucleic acid- and mRNA-based therapeutics, are well established. Thus, future research on LNPs will focus on addressing the following: expanding the scope of drug delivery to different constituents of the human body, expanding the number of diseases that can be targeted, and studying the change in the pharmacokinetics of LNPs under physiological and pathological conditions. This review article provides an overview of recent advances aimed at expanding the application of LNPs, focusing on the pharmacokinetics and advantages of LNPs. In addition, analytical techniques, library construction and screening, rational design, active targeting, and applicability to gene editing therapy have also been discussed.  相似文献   
79.
《Vaccine》2022,40(26):3490-3494
The current WHO Recommendations to assure the quality, safety and efficacy of live attenuated yellow fever vaccines were adopted in 2010. This document recommends that vaccine virus master and working seed lots should be tested for viscerotropism, immunogenicity and neurovirulence in monkeys. A vaccine manufacturer has reported, recently, discrepancies on the clinical scoring of monkeys during assessment of working seed lots and suggested aligning neurotropism assessment of yellow fever vaccines virus seed lots with that of neurovirulence testing of polio vaccines virus seed lots. In this approach, clinical signs are recorded but do not form part of the assessment or pass/fail criteria. At its 71st meeting in August 2020, the ECBS agreed to establish a drafting group and to consult with manufacturers and other stakeholders on the proposed amendment. Then a survey had been conducted to seek opinions of stakeholders on the neurotropism testing and revision of current WHO Recommendations for yellow fever vaccines. It was recognized from the answers of the survey that the test for neurovirulence in monkeys presents several technical challenges which could be addressed in the amended version of the Recommendations.On 18–19 March 2021, a virtual WHO working group meeting was held to discuss a proposed draft of the amended text with participants of yellow fever vaccine manufacturers and relevant regulators. Overall, there was a consensus among manufacturers and regulators that clinical evaluation provides important information and should be retained as part of the neurotropism test. However, there was also agreement that the test is somewhat subjective, and that analysis can be difficult. It was recognized that there was potential for improvement in both test execution and analysis to increase harmonization between manufacturers. Alternative tests to the non-human primates neurovirulence test would be useful but it was agreed that none seem to be sufficiently developed at present. Based on these working group discussions, it was proposed that the appendix on neurotropism test to be further revised by the WHO drafting group and submitted to ECBS for review and adoption.Issues other than neurotropism test were discussed in the meeting as well. There were a number of points identified during the meeting, such as new platform of production, animal models, deep sequencing, international standards, that are outside the current recommendations that are worthy of further discussion. Therefore, it is recommended that there would be a future meeting with various stakeholders to discuss the potential revision of the whole Recommendations for yellow fever vaccines in order to meet the current needs.  相似文献   
80.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
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