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1.
Bioorg Med Chem ; 88-89: 117332, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37210791

RESUMEN

Pyridachlometyl is a unique pyridazine fungicide with a novel mode of action. Herein, we describe the pathway for the invention of pyridachlometyl. First, we identified a diphenyl-imidazo[1,2-a]pyrimidine as our proprietary lead with potent fungicidal activity. Then, aiming to simplify the chemical structure, we applied judicious estimations to explore monocyclic heterocycles as pharmacophores. This enabled the identification of a novel class of tetrasubstituted pyridazine compounds with potent fungicidal activity, likely retaining the same mode of action as the aforementioned compounds. The findings indicated bioisosteric similarity between diphenyl-imidazo[1,2-a]pyrimidine and pyridazine. Further structure-activity and mammalian safety investigations of pyridazine compounds resulted in the discovery of pyridachlometyl as a candidate for commercial development.


Asunto(s)
Fungicidas Industriales , Piridazinas , Animales , Fungicidas Industriales/farmacología , Fungicidas Industriales/química , Compuestos de Bifenilo , Pirimidinas/farmacología , Piridazinas/farmacología , Piridazinas/química , Relación Estructura-Actividad , Mamíferos
2.
Cardiol Young ; 33(11): 2297-2311, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36721907

RESUMEN

The optimal treatment strategy using pulmonary vasodilators in pulmonary arterial hypertension associated with CHD (PAH-CHD) remains controversial. We aimed to compare the efficacy and safety of pulmonary vasodilators in PAH-CHD. PubMed and EMBASE databases were searched through May 2022 and a network meta-analysis was conducted. The primary outcomes were mean difference of changes in 6-minute walk distance, NYHA functional class, and N-terminal pro-brain natriuretic peptide. The secondary outcomes included pulmonary vascular resistance, mean pulmonary arterial pressure, and resting oxygen saturation. We identified 14 studies, yielding 807 patients with PAH-CHD. Bosentan and sildenafil were associated with a significant increase in 6-minute walk distance from baseline compared with placebo (MD 48.92 m, 95% CI 0.32 to 97.55 and MD 59.70 m, 95% CI 0.88 to 118.53, respectively). Bosentan, sildenafil, and combination of bosentan and sildenafil were associated with significant improvement in NYHA functional class compared with placebo (MD -0.33, 95% CI -0.51 to -0.14, MD -0.58, 95% CI -0.75 to -0.22 and MD -0.62, 95% CI -0.92 to -0.31, respectively). Bosentan and sildenafil were also associated with significant improvements in secondary outcomes. These findings were largely confirmed in the subgroup analysis. Various adverse events were reported; however, serious adverse event rates were relatively low (4.8-8.7%), including right heart failure, acute kidney injury, respiratory failure, hypotension, and discontinuation of pulmonary vasodilators. In conclusion, bosentan and sildenafil were the most effective in improving prognostic risk factor such as 6-minute walk distance and NYHA class. Overall, pulmonary vasodilators were well tolerated in PAH-CHD.


Asunto(s)
Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Humanos , Vasodilatadores/uso terapéutico , Bosentán/uso terapéutico , Citrato de Sildenafil/uso terapéutico , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/etiología , Antihipertensivos/uso terapéutico , Sulfonamidas/uso terapéutico , Metaanálisis en Red , Resultado del Tratamiento , Hipertensión Pulmonar Primaria Familiar/complicaciones
3.
Pediatr Cardiol ; 43(5): 986-994, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34981140

RESUMEN

To date, there has been limited investigation of bioabsorbable atrial septal defect (ASD) or patent foramen ovale (PFO) closure devices using clinically relevant large animal models. The purpose of this study is to explore the function and safety of a bioabsorbable ASD occluder (BAO) system for PFO and/or secundum ASD transcatheter closure. Using a sheep model, the intra-atrial septum was evaluated by intracardiac echo (ICE). If a PFO was not present, atrial communication was created via transseptal puncture. Device implantation across the intra-atrial communication was performed with fluoroscopic and ICE guidance. Our 1st generation device consisted of a main structure of thin Poly(L-lactide-co-epsilon-caprolactone) (PLCL) fibers, and an internal Poly glycolic acid (PGA) fabric. Four procedures validated procedure feasibility. Subsequently, device design was modified for improved transcatheter delivery. The 2nd generation device has a two-layered structure and was implanted in six sheep. Results showed procedural success in 9/10 (90%) animals. With deployment, the 1st generation device did not reform into its original disk shape and did not conform nicely along the atrial septum. The 2nd generation device was implanted in six animals, 3 out of 6 survived out to 1 year. At 1 year post implantation, ICE confirmed no residual shunting. By necropsy, biomaterials had partially degraded, and histology of explanted samples revealed significant device endothelialization and biomaterial replacement with a collagen layer. Our results demonstrate that our modified 2nd generation BAO can be deployed via minimally invasive percutaneous transcatheter techniques. The BAO partially degrades over 1 year and is replaced by host native tissues. Future studies are needed prior to clinical trials.


Asunto(s)
Foramen Oval Permeable , Defectos del Tabique Interatrial , Dispositivo Oclusor Septal , Implantes Absorbibles , Animales , Cateterismo Cardíaco/métodos , Estudios de Seguimiento , Foramen Oval Permeable/cirugía , Atrios Cardíacos , Defectos del Tabique Interatrial/diagnóstico por imagen , Defectos del Tabique Interatrial/cirugía , Humanos , Ovinos , Resultado del Tratamiento
4.
Bioorg Med Chem ; 28(1): 115211, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31753801

RESUMEN

Quinone outside inhibitors (QoIs) are one of the major agricultural fungicide groups used worldwide. However, the development of resistance by different pathogenic species associated with specific mutation at the target gene site is becoming a critical issue for the sustainable use of QoIs. The authors aimed to design a novel QoI molecule to overcome the aforementioned issue. A rational approach to avoid steric hindrance between the QoI molecule and the mutated target site was successfully employed. The resulting compound, metyltetraprole, is characterized by 3-substituted central ring with a tetrazolinone moiety, the key structure to retain potent activity against QoI-resistant mutants. Metyltetraprole is a promising new fungicide under commercial development, and its development in this study has paved the way to overcoming resistance to QoI fungicides.


Asunto(s)
Antifúngicos/farmacología , Descubrimiento de Drogas , Fungicidas Industriales/farmacología , Estrobilurinas/farmacología , Tetrazoles/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Relación Dosis-Respuesta a Droga , Farmacorresistencia Fúngica/efectos de los fármacos , Hongos/efectos de los fármacos , Fungicidas Industriales/síntesis química , Fungicidas Industriales/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Estrobilurinas/síntesis química , Estrobilurinas/química , Relación Estructura-Actividad , Tetrazoles/síntesis química , Tetrazoles/química
5.
Gan To Kagaku Ryoho ; 45(3): 477-479, 2018 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-29650910

RESUMEN

With the aging of the population of Japan and Westernization of the dietary life, the number of cases in which cardiovascular diseases are merged in non-cardiac surgery is increasing year by year.Many of the abdominal aortic aneurysms are asymptomatic and it is not uncommon to be discovered accidentally in preoperative examination of non-cardiac surgery.When gastrointestinal surgery involves malignant diseases of the gastrointestinal tract and abdominal aortic aneurysm, the two life prognosis-related diseases are merged, depending on the severity and urgency of the disease for each case, its treatment to determine the priority order.Abdominal aortic aneurysm occurred at the time of malignant disease surgery in 14 cases of gastrointestinal cancer patients who underwent surgery at the department during the 5 years from 2012 to 2016.T he actual condition of treatment for these cases was investigated.


Asunto(s)
Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/cirugía , Neoplasias Gastrointestinales/complicaciones , Neoplasias Gastrointestinales/cirugía , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos del Sistema Digestivo , Humanos , Masculino , Complicaciones Posoperatorias , Stents
6.
Kyobu Geka ; 69(9): 746-9, 2016 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-27476562

RESUMEN

A 48-year-old man was refered to our hospital for the treatment of bicusp aortic valve and severe aortic regurgitation. He underwent Bentall procedure (SJM 25mm+HemashieldØ 28 mm composite graft). Temporary epicardial pacing lead( TPL) was placed on the right ventricle at the opetation, and was cut on his skin surface prior to discharge because of difficulty in traction removal. After 15 years from operation, follow up computered tomography and echocardiography showed migration of 2 retaining TPLs extending from vascular graft of ascending aorta to the right innominate artery. We performed Redo-median sternotomy and removed the TPLs. This is the 1st reported case of a migrated temporary pacing lead into the vascular graft of ascending aorta under noninfectious conditions.


Asunto(s)
Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Procedimientos Quirúrgicos Cardiovasculares , Ecocardiografía Tridimensional , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
7.
Pest Manag Sci ; 80(6): 2874-2880, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38345375

RESUMEN

BACKGROUND: Resistance to succinate dehydrogenase inhibitor (SDHI) fungicides has been reported in some rust fungi within Pucciniales. However, measuring the resistance factors conferred by a specific substitution at the target site is difficult for most species because of the difficulty in performing in vitro experiments and the complexity of the binuclear state in these obligate parasites. We focused on Puccinia horiana because it easily forms homozygous basidiospores that are sensitive to SDHIs during in vitro germination, whereas the uredospores of other rust fungi are less sensitive. RESULTS: We identified two substitutions, SdhC-I88F and SdhD-C125Y, that drive SDHI resistance in Pu. horiana. Using basidiospore germination inhibition tests, we measured the resistance factors for six SDHI fungicides in Pu. horiana isolates harboring SdhC-I88F substitutions, wherein orthologous substitutions were most frequently observed in SDHI-resistant Pucciniales, such as soybean rust (Phakopsora pachyrhizi). The resistance factors were high for penthiopyrad and benzovindiflupyr (>150), moderate for oxycarboxin and inpyrfluxam (10-30), and low for mepronil and fluxapyroxad (3-10). The most potent SDHI against SdhC-I88F-harboring isolates was inpyrfluxam, with a half-maximal effective concentration (EC50) of 0.0082 mg L-1 owing to its high intrinsic activity. SdhD-C125Y played a minor, but significant role in increasing the resistance factors (one- to tenfold increases), depending on the individual SDHIs. CONCLUSION: This study is the first to use basidiospore germination inhibitory tests to quantify the resistance factors for SDHI-resistant Pucciniales. Owing to its homozygous binucleate nature and the high availability of basidiospores, Pu. horiana is useful for investigating SDHI resistance in Pucciniales. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Sustitución de Aminoácidos , Farmacorresistencia Fúngica , Fungicidas Industriales , Puccinia , Succinato Deshidrogenasa , Succinato Deshidrogenasa/genética , Succinato Deshidrogenasa/antagonistas & inhibidores , Fungicidas Industriales/farmacología , Farmacorresistencia Fúngica/genética , Enfermedades de las Plantas/microbiología , Chrysanthemum/microbiología , Proteínas Fúngicas/genética , Basidiomycota/fisiología , Basidiomycota/genética
8.
Pest Manag Sci ; 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853401

RESUMEN

Pyridachlometyl is a novel tubulin dynamics modulator fungicide developed by Sumitomo as a new agent designed to tackle fungicide resistance. Pyridachlometyl is being developed as a first-in-class molecule with an anti-tubulin mode of action, the chemical structure of which is characterized by a unique tetrasubstituted pyridazine ring. The first commercial product 'Fuseki flowable' received initial registration in 2023 in Japan. The concepts of the discovery project, optimization of chemical structures, and biological profiles are reviewed herein. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

9.
Tissue Eng Part A ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39302061

RESUMEN

Severe coronary artery disease is often treated with a coronary artery bypass graft using an autologous blood vessel. When this is not available, a commercially available synthetic graft can be used as an alternative but is associated with high failure rates and complications. Therefore, research focus has shifted towards the development of biodegradable, regenerative vascular grafts that can convert into neoarteries. We previously developed an electrospun tropoelastin (TE)-polyglycerol sebacate (PGS) vascular graft that rapidly regenerated into a neoartery, with a cellular composition and extracellular matrix approximating the native aorta. We noted however that the TE-PGS graft underwent dilation until sufficient neotissue had been regenerated. This study investigated the mechanisms behind the observed dilation following TE-PGS vascular graft implantation in mice. We saw more pronounced dilation at the graft middle compared to the graft proximal and graft distal regions at 8 weeks post-implantation. Histological analysis revealed less degradation at the graft middle, although the remaining graft material appeared pitted, suggesting compromised structural and mechanical integrity. We also observed delayed cellular infiltration and extracellular matrix (ECM) deposition at the graft middle, corresponding with the area's reduced ability to resist dilation. In contrast, the graft proximal region exhibited greater degradation and significantly enhanced cellular infiltration and ECM regeneration. The non-uniform dilation was attributed to the combined effect of the regional differences in graft degradation and arterial regeneration. Consideration of these findings is crucial for graft optimization prior to its use in clinical applications.

10.
J Am Heart Assoc ; 13(4): e031823, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38353265

RESUMEN

BACKGROUND: Perfusion deficits contribute to symptom severity, morbidity, and death in peripheral artery disease (PAD); however, no standard method for quantifying absolute measures of skeletal muscle perfusion exists. This study sought to preclinically test and clinically translate a positron emission tomography (PET) imaging approach using an atherosclerosis-targeted radionuclide, fluorine-18-sodium fluoride (18F-NaF), to quantify absolute perfusion in PAD. METHODS AND RESULTS: Eight Yorkshire pigs underwent unilateral femoral artery ligation and dynamic 18F-NaF PET/computed tomography imaging on the day of and 2 weeks after occlusion. Following 2-week imaging, calf muscles were harvested to quantify microvascular density. PET methodology was validated with microspheres in 4 additional pig studies and translated to patients with PAD (n=39) to quantify differences in calf perfusion across clinical symptoms/stages and perfusion responses in a case of revascularization. Associations between PET perfusion, ankle-brachial index, toe-brachial index, and toe pressure were assessed in relation to symptoms. 18F-NaF PET/computed tomography quantified significant deficits in calf perfusion in pigs following arterial occlusion and perfusion recovery 2 weeks after occlusion that coincided with increased muscle microvascular density. Additional studies confirmed that PET-derived perfusion measures agreed with microsphere-derived perfusion measures. Translation of imaging methods demonstrated significant decreases in calf perfusion with increasing severity of PAD and quantified perfusion responses to revascularization. Perfusion measures were also significantly associated with symptom severity, whereas traditional hemodynamic measures were not. CONCLUSIONS: 18F-NaF PET imaging quantifies perfusion deficits that correspond to clinical stages of PAD and represents a novel perfusion imaging strategy that could be partnered with atherosclerosis-targeted 18F-NaF PET imaging using a single radioisotope injection. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03622359.


Asunto(s)
Músculo Esquelético , Enfermedad Arterial Periférica , Animales , Humanos , Músculo Esquelético/diagnóstico por imagen , Perfusión , Enfermedad Arterial Periférica/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Fluoruro de Sodio , Porcinos
11.
Kyobu Geka ; 66(12): 1061-5, 2013 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-24322313

RESUMEN

A 59-year-old man was admitted for evaluation of short of breath and bilateral leg edema that had progressively worsened over 3 months. Chest computed tomography revealed marked pericardial thickening. Cardiac echocardiography revealed right heart volume load and diastolic dysfunction. Cardiac catheterization revealed a dip-and-plateau pattern of the pressure curve of right ventricule (RV)without any coronary disease. On a diagnosis of heart failure due to pericardial constriction, he underwent pericardiectomy under cardiopulmonary bypass. Multiple longitudinal and transverse incisions like a waffle were made in the thickened epicardium and improved the hemodynamics. The symptoms improved after surgery. As serum level of immunoglobulin G(IgG)4 was elevated and IgG4-positive plasma cells were recognized in the resected pericardium, diagnosis of constrictive pericarditis of hyper-IgG4 disease was made.


Asunto(s)
Inmunoglobulina G/inmunología , Pericarditis Constrictiva/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Humanos , Masculino , Persona de Mediana Edad , Pericarditis Constrictiva/inmunología
12.
Front Cardiovasc Med ; 10: 1018203, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36926047

RESUMEN

Background: Acute decompensated heart failure (HF) and cardiogenic shock (CS) frequently are refractory to conservative treatment and require mechanical circulatory support (MCS). We report our early clinical experience and evaluate patient outcomes with the newer generation surgical Impella 5.5. Methods: Seventy patients that underwent Impella 5.5 implantation between October 2019 and December 2021 at a single center were enrolled in this study. Pre-operative characteristics, peri-operative clinical course information, and post-operative outcomes were retrospectively collected. Results: Fifty-seven (81%) patients survived to discharge, and 51 (76%) patients survived at the time of the first 30 days post-discharge visit. Thirty-one patients (44%) received Impella support for a bridge to advanced surgical heart failure therapy (transplant or durable left ventricular assist device [LVAD]), 27 (39%) cases were used for a bridge to recovery/decision and 12 (17.1%) cases was used for planned perioperative support for high-risk cardiac surgery procedure. Conclusion: Our results suggest that Impella 5.5 provides favorable survival in the management of HF and CS, particularly used for a bridge to heart transplant or LVAD. Early extubation and mobilization with high flow circulatory support allowed effective tailoring of MCS approaches from peri-operative support for high-risk cardiac surgery, bridge to recovery, and to advanced surgical heart failure therapy.

13.
JTCVS Open ; 15: 433-445, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37808023

RESUMEN

Objectives: Palliative treatment of cyanotic congenital heart disease (CCHD) uses systemic-to-pulmonary conduits, often a modified Blalock-Taussig-Thomas shunt (mBTTs). Expanded polytetrafluoroethylene (ePTFE) mBTTs have associated risks for thrombosis and infection. The Human Acellular Vessel (HAV) (Humacyte, Inc) is a decellularized tissue-engineered blood vessel currently in clinical trials in adults for vascular trauma, peripheral artery disease, and end-stage renal disease requiring hemodialysis. In addition to restoring blood flow, the engineered HAV demonstrates the capacity for host cellular remodeling into native-like vasculature. Here we report preclinical evaluation of a small-diameter (3.5 mm) HAV as a mBTTs in a non-human primate model. Methods: We implanted 3.5 mm HAVs as right subclavian artery to pulmonary artery mBTTs in non-immunosuppressed juvenile rhesus macaques (n = 5). HAV patency, structure, and blood flow were assessed by postoperative imaging from 1 week to 6 months. Histology of HAVs and surrounding tissues was performed. Results: Surgical procedures were well tolerated, with satisfactory anastomoses, showing feasibility of using the 3.5 mm HAV as a mBTTs. All macaques had some immunological reactivity to the human extracellular matrix, as expected in this xenogeneic model. HAV mBTTs remained patent for up to 6 months in animals, exhibiting mild immunoreactivity. Two macaques displaying more severe immunoreactivity to the human HAV material developed midgraft dilatation without bleeding or rupture. HAV repopulation by host cells expressing smooth muscle and endothelial markers was observed in all animals. Conclusions: These findings may support use of 3.5 mm HAVs as mBTTs in CCHD and potentially other pediatric vascular indications.

14.
Expert Opin Biol Ther ; 22(3): 433-440, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34427482

RESUMEN

INTRODUCTION: Cardiovascular disease (CVD) is the leading cause of death in western countries. Although surgical outcomes for CVD are dramatically improving with the development of surgical techniques, medications, and perioperative management strategies, adverse postoperative events related to the use of artificial prosthetic materials are still problematic. Moreover, in pediatric patients, using these artificial materials make future re-intervention inevitable due to their lack of growth potential. AREAS COVERED: This review focuses on the most current tissue-engineering (TE) technologies to treat cardiovascular diseases and discusses their limitations through reports ranging from animal studies to clinical trials. EXPERT OPINION: Tissue-engineered structures, derived from a patient's own autologous cells/tissues and biodegradable polymer scaffolds, can provide mechanical function similar to non-diseased tissue. However, unlike prosthetic materials, tissue-engineered structures are hypothetically more biocompatible and provide growth potential, saving patients from additional or repetitive interventions. While there are many methods being investigated to develop TE technologies in the hopes of finding better options to tackle CVD, most of these approaches are not ready for clinical use or trials. However, tissue engineering has great promise to potentially provide better treatment options to vastly improve cardiovascular surgical outcomes.


Asunto(s)
Enfermedades Cardiovasculares , Ingeniería de Tejidos , Animales , Prótesis Vascular , Enfermedades Cardiovasculares/cirugía , Niño , Humanos , Polímeros , Ingeniería de Tejidos/métodos , Andamios del Tejido , Trasplante Autólogo
15.
Biomedicines ; 10(6)2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35740460

RESUMEN

Cardiovascular-related medical conditions remain a significant cause of death worldwide despite the advent of tissue engineering research more than half a century ago. Although autologous tissue is still the preferred treatment, donor tissue is limited, and there remains a need for tissue-engineered vascular grafts (TEVGs). The production of extensive vascular tissue (>1 cm3) in vitro meets the clinical needs of tissue grafts and biological research applications. The use of TEVGs in human patients remains limited due to issues related to thrombogenesis and stenosis. In addition to the advancement of simple manufacturing methods, the shift of attention to the combination of synthetic polymers and bio-derived materials and cell sources has enabled synergistic combinations of vascular tissue development. This review details the selection of biomaterials, cell sources and relevant clinical trials related to large diameter vascular grafts. Finally, we will discuss the remaining challenges in the tissue engineering field resulting from complex requirements by covering both basic and clinical research from the perspective of material design.

16.
Adv Mater ; 34(47): e2205614, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36120809

RESUMEN

Native arteries contain a distinctive intima-media composed of organized elastin and an adventitia containing mature collagen fibrils. In contrast, implanted biodegradable small-diameter vascular grafts do not present spatially regenerated, organized elastin. The elastin-containing structures within the intima-media region encompass the elastic lamellae (EL) and internal elastic lamina (IEL) and are crucial for normal arterial function. Here, the development of a novel electrospun small-diameter vascular graft that facilitates de novo formation of a structurally appropriate elastin-containing intima-media region following implantation is described. The graft comprises a non-porous microstructure characterized by tropoelastin fibers that are embedded in a PGS matrix. After implantation in mouse abdominal aorta, the graft develops distinct cell and extracellular matrix profiles that approximate the native adventitia and intima-media by 8 weeks. Within the newly formed intima-media region there are circumferentially aligned smooth muscle cell layers that alternate with multiple EL similar to that found in the arterial wall. By 8 months, the developed adventitia region contains mature collagen fibrils and the neoartery presents a distinct IEL with thickness comparable to that in mouse abdominal aorta. It is proposed that this new class of material can generate the critically required, organized elastin needed for arterial regeneration.


Asunto(s)
Prótesis Vascular , Elastina , Ratones , Animales , Miocitos del Músculo Liso , Arterias , Colágeno
17.
Commun Med (Lond) ; 2: 3, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35603301

RESUMEN

Background: Tissue-engineered vascular grafts (TEVGs) have the potential to advance the surgical management of infants and children requiring congenital heart surgery by creating functional vascular conduits with growth capacity. Methods: Herein, we used an integrative computational-experimental approach to elucidate the natural history of neovessel formation in a large animal preclinical model; combining an in vitro accelerated degradation study with mechanical testing, large animal implantation studies with in vivo imaging and histology, and data-informed computational growth and remodeling models. Results: Our findings demonstrate that the structural integrity of the polymeric scaffold is lost over the first 26 weeks in vivo, while polymeric fragments persist for up to 52 weeks. Our models predict that early neotissue accumulation is driven primarily by inflammatory processes in response to the implanted polymeric scaffold, but that turnover becomes progressively mechano-mediated as the scaffold degrades. Using a lamb model, we confirm that early neotissue formation results primarily from the foreign body reaction induced by the scaffold, resulting in an early period of dynamic remodeling characterized by transient TEVG narrowing. As the scaffold degrades, mechano-mediated neotissue remodeling becomes dominant around 26 weeks. After the scaffold degrades completely, the resulting neovessel undergoes growth and remodeling that mimicks native vessel behavior, including biological growth capacity, further supported by fluid-structure interaction simulations providing detailed hemodynamic and wall stress information. Conclusions: These findings provide insights into TEVG remodeling, and have important implications for clinical use and future development of TEVGs for children with congenital heart disease.

18.
Pest Manag Sci ; 77(3): 1226-1234, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33051963

RESUMEN

BACKGROUND: Metyltetraprole is a new quinone outside inhibitor (QoI) fungicide showing potent activity against QoI-resistant fungi that possess the G143A cytochrome b mutation, which confers resistance to existing QoIs such as trifloxystrobin. For its sustainable use, monitoring of metyltetraprole sensitivity is necessary and the establishment of appropriate methodology is important in each pathogen species. RESULTS: In Cercospora beticola, the causal agent of sugar beet leaf spot, some isolates were less sensitive to metyltetraprole (EC50 > 1 mg L-1 , higher than the saturated concentration) using the common agar plate method, even with 100 mg L-1 salicylhydroxamic acid, an alternative oxidase inhibitor. However, microtiter tests (EC50 < 0.01 mg L-1 ), conidial germination tests (EC50 < 0.01 mg L-1 ) and in planta tests (>80% control at 75 mg L-1 run-off spraying) confirmed that all tested isolates were highly sensitive to metyltetraprole. For trifloxystrobin, G143A mutants were clearly resistant upon microtiter plate tests (median EC50 > 2 mg L-1 ) and distinct from wild-type isolates (median EC50 < 0.01 mg L-1 ). Notably, mycelium fragments were usable for the microtiter plate tests and the test was applicable for isolates that do not form sufficient conidia. Our monitoring study by microtiter plate tests did not indicate the presence of metyltetraprole-resistant C. beticola isolates in populations in Hokkaido, Japan. CONCLUSION: The microtiter tests were revealed to be useful for monitoring the sensitivity of C. beticola to metyltetraprole and trifloxystrobin. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Farmacorresistencia Fúngica , Fungicidas Industriales , Cercospora , Citocromos b , Farmacorresistencia Fúngica/genética , Fungicidas Industriales/farmacología , Japón
19.
Biomedicines ; 9(5)2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-33925558

RESUMEN

Bioabsorbable materials made from polymeric compounds have been used in many fields of regenerative medicine to promote tissue regeneration. These materials replace autologous tissue and, due to their growth potential, make excellent substitutes for cardiovascular applications in the treatment of congenital heart disease. However, there remains a sizable gap between their theoretical advantages and actual clinical application within pediatric cardiovascular surgery. This review will focus on four areas of regenerative medicine in which bioabsorbable materials have the potential to alleviate the burden where current treatment options have been unable to within the field of pediatric cardiovascular surgery. These four areas include tissue-engineered pulmonary valves, tissue-engineered patches, regenerative medicine options for treatment of pulmonary vein stenosis and tissue-engineered vascular grafts. We will discuss the research and development of biocompatible materials reported to date, the evaluation of materials in vitro, and the results of studies that have progressed to clinical trials.

20.
Ann Thorac Surg ; 111(4): 1234-1241, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32946845

RESUMEN

BACKGROUND: Small diameter (<6 mm), bioabsorbable, arterial, tissue-engineered vascular grafts (TEVGs) remain limited by thromboembolism. The objective of this study was to test whether heparin-eluting (HE) TEVGs prevent early thrombosis in a large animal model. METHODS: TEVGs were created with an outer poly-ε-caprolactone electrospun nanofiber layer, with a 15-µm average pore size and an inner layer composed of a 50:50 poly(L-lactide-co-ε-caprolactone) copolymer. Adult female sheep (n = 5) underwent bilateral carotid artery interposition grafting, with a control TEVG in 1 carotid artery and an HE TEVG in the contralateral position. Animals were followed for 8 weeks with weekly Duplex ultrasonography to monitor TEVG performance. RESULTS: All sheep survived to the designated endpoint. At 8 weeks all 5 HE TEVGs were patent. Three of 5 control TEVGs had early thrombotic occlusion at <1 week. More than 97% of heparin release occurred within the first 24 hours. Histologic evaluation of the HE TEVG displayed cellularity like a native carotid artery with no evidence of calcification. Significantly fewer platelets adhered to the HE TEVG than to the control TEVG (P < .001). CONCLUSIONS: This study suggests HE TEVGs prevent acute graft thrombosis. We hypothesize that the HE properties of the HE TEVG during vascular endothelialization is useful for maintaining TEVG patency. This technique may aid in the translation of small arterial TEVGs to the clinic.


Asunto(s)
Implantación de Prótesis Vascular/métodos , Prótesis Vascular , Arterias Carótidas/cirugía , Heparina/farmacología , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Anticoagulantes/farmacología , Femenino , Modelos Animales , Diseño de Prótesis , Ovinos
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