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1.
Nat Mater ; 23(4): 570-576, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38297141

RESUMO

Soft building blocks, such as micelles, cells or soap bubbles, tend to adopt near-spherical geometry when densely packed together. As a result, their packing structures do not extend beyond those discovered in metallic glasses, quasicrystals and crystals. Here we report the emergence of two Frank-Kasper phases from the self-assembly of five-fold symmetric molecular pentagons. The µ phase, an important intermediate in superalloys, is indexed in soft matter, whereas the ϕ phase exhibits a structure distinct from known Frank-Kasper phases in metallic systems. We find a broad size and shape distribution of self-assembled mesoatoms formed by molecular pentagons while approaching equilibrium that contribute to the unique packing structures. This work provides insight into the manipulation of soft building blocks that deviate from the typical spherical geometry and opens avenues for the fabrication of 'soft alloy' structures that were previously unattainable in metal alloys.

2.
Proc Natl Acad Sci U S A ; 119(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35022240

RESUMO

The quasiperiodic structures in metal alloys have been known to depend on the existence of icosahedral order in the melt. Among different phases observed in intermetallics, decagonal quasicrystal (DQC) structures have been identified in many glass-forming alloys yet remain inaccessible in bulk-state condensed soft matters. Via annealing the mixture of two giant molecules, the binary system assemblies into an axial DQC superlattice, which is identified comprehensively with meso-atomic accuracy. Analysis indicates that the DQC superlattice is composed of mesoatoms with an unusually broad volume distribution. The interplays of submesoatomic (molecular) and mesoatomic (supramolecular) local packings are found to play a crucial role in not only the formation of the metastable DQC superlattice but also its transition to dodecagonal quasicrystal and Frank-Kasper σ superlattices.

3.
Eur J Vasc Endovasc Surg ; 67(2): 192-331, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38307694

RESUMO

OBJECTIVE: The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy. METHODS: The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence. RESULTS: A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed. CONCLUSION: The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

4.
Ann Vasc Surg ; 105: 89-98, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38579910

RESUMO

BACKGROUND: Endovascular deep vein arteriaization (DVA) is a novel technique aimed at salvaging peripheral arterial disease unamenable to conventional surgical intervention. This study aims to review contemporary literature on the efficacy, safety, and durability of DVA on patients with no-option critical limb ischemia (NO-CLI). METHODS: The study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, using predefined search terms of "percutaneous deep vein arterialization" or "percutaneous deep venous arterialization" in PubMed, Web of Sciences, OvidSP, and Embase. Only studies with 5 or more patients were included, and studies involving open or hybrid DVA were excluded. The primary outcomes included technical success and primary amputation rates. Secondary outcomes included rates of wound healing, complication, reintervention, and all-cause mortality. RESULTS: Ten studies encompassing a total of 233 patients were included. Patients were primarily those deemed to have NO-CLI. The median follow-up period was 12 months (range 1-63 months). The technical success rate was 97% (95% confidence interval [CI] 96.2%-97.9%) and the major amputation rate was 21.8% (95% 21.1%-22.4%). The wound healing rate was 69.5% (95% CI 67.9-71.0%), complication rate was 13.8% (95% CI 11.7%-15.9%), reintervention rate was 37.4% (95% CI 34.9%-39.9%), and all-cause mortality rate was 15.7% (95% CI 14.1%-17.2%). CONCLUSIONS: Our study showed that endovascular DVA is safe for patients with NO-CLI. Nonetheless, studies were small with follow-up period of less than 1 year. There is currently lack of level 1 evidence to recommend routine use in patients with NO-CLI.


Assuntos
Amputação Cirúrgica , Procedimentos Endovasculares , Salvamento de Membro , Doença Arterial Periférica , Humanos , Resultado do Tratamento , Fatores de Risco , Fatores de Tempo , Doença Arterial Periférica/cirurgia , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Idoso , Feminino , Masculino , Veias/cirurgia , Veias/fisiopatologia , Pessoa de Meia-Idade , Cicatrização , Estado Terminal , Idoso de 80 Anos ou mais , Isquemia/cirurgia , Isquemia/fisiopatologia , Isquemia/mortalidade , Isquemia/diagnóstico por imagem
5.
Ann Vasc Surg ; 100: 172-183, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37898457

RESUMO

BACKGROUND: To perform a systematic review on contemporary outcomes of endovascular repair and open surgical repair (OSR) for the treatment of mycotic aortic aneurysm (MAA). METHODS: A comprehensive literature search on the management of MAAs with endovascular repair or OSR was performed between January 1998 and January 2023. Patient demographics, early and late outcomes were analyzed with respect to treatment modality and MAA location. RESULTS: Forty-eight articles were included, encompassing a total of 1,358 patients (75.8% male; mean age 66.9 years; 1,372 aneurysms) treated by open (49.8%) or endovascular (50.2%) repair. Salmonella spp., and Staphylococcus spp. were the most prevalent pathogens in Asian and European countries respectively. An increasing number of descending thoracic MAAs were managed by endovascular repair (27.9% vs. 12.8%). Early mortality rates for supra- and infra-renal MAAs managed by endovascular repair were lower than OSR (suprarenal 5.4% vs. 43.2%; infrarenal 1.8% vs. 16.7%). Overall, endovascular repair demonstrated lower intraoperative (1.0% vs. 1.8%) and early mortality (6.5% vs. 15.9) rates than OSR. However, endovascular repair was associated with higher late sepsis rate (5.7% vs. 0.9%) and reintervention rate (17.6% vs. 7.3%). Pooled survival rates at 1- and 5-year were similar between the 2 groups. CONCLUSIONS: Current literature suggest that endovascular repair is an effective and safe alternative to OSR for descending thoracic, suprarenal, and infrarenal MAAs. However, endovascular repair is associated with higher risk of infection-related complications and reintervention during follow-up.


Assuntos
Aneurisma Infectado , Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Masculino , Idoso , Feminino , Aneurisma da Aorta Abdominal/cirurgia , Fatores de Risco , Implante de Prótese Vascular/efeitos adversos , Complicações Pós-Operatórias , Resultado do Tratamento , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/cirurgia , Estudos Retrospectivos
6.
Ann Neurol ; 92(2): 164-172, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35285095

RESUMO

OBJECTIVE: This study was undertaken to evaluate a multicomponent health system intervention designed to reduce escalating disease-modifying treatment (DMT) expenditures and improve multiple sclerosis (MS) outcomes by increasing use of preferred formulary and highly effective DMTs (HETs). METHODS: We conducted a trend study of treatment utilization and expenditure outcomes prior to (2009-2011) and during (2012-2018) MS Treatment Optimization Program (MSTOP) implementation in Kaiser Permanente Southern California (KPSC) compared to a Kaiser Permanente region of similar size. Annual relapse rates (ARRs) were obtained from KPSC's electronic health records. RESULTS: Adherence to preferred formulary DMTs increased from 25.4% in 2011 to 72.2% in 2017 following MSTOP implementation in KPSC and 22.1% to 43.8%, respectively, in the comparator. KPSC's annual DMT expenditures in 2018 were less than in 2011 despite an 11.3% increase in DMT-treated members. The decline in average per patient per year of treatment expenditures from a peak of $43.1 K in 2014 to $26.3 K in 2018 in KPSC was greater than the comparator, which peaked at $52.1 K and declined to $40.0 K in 2018. Over the 7 years following initiation of MSTOP, cumulative MS DMT expenditures were $161.6 million less than the comparator. HET use increased to 62.5% of per patient treatment-years versus 32.4% in the comparator. This corresponded to a 69% decline in adjusted ARR (95% confidence interval = 64.1-73.2%; p < 0.0001) among DMT-treated patients in KPSC. INTERPRETATION: A novel, expert-led health system intervention reduced MS DMT expenditures despite rising prices while simultaneously reducing MS relapse rates. Our focus on health system progress toward meaningful, measurable targets could serve as a model to improve quality and affordability of MS care in other settings. ANN NEUROL 2022;92:164-172.


Assuntos
Esclerose Múltipla , Gastos em Saúde , Humanos , Esclerose Múltipla/tratamento farmacológico , Recidiva , Estudos Retrospectivos
7.
J Vasc Surg ; 77(1): 150-157, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36087832

RESUMO

BACKGROUND: Spontaneous isolated mesenteric artery (celiac axis or superior mesenteric artery [SMA]) dissection (IMAD) is a rare clinical entity. The aim of the present study was to examine the patient demographics, comorbidities, clinical and radiologic features, management, and prognosis and to identify the risk factors predictive of symptoms. METHODS: We performed a single-center, retrospective review from November 2005 to November 2021 of prospectively collected data from patients with a diagnosis of IMAD. The clinical data and radiologic images were reviewed, and statistical analysis was performed to compare the symptomatic and asymptomatic groups. RESULTS: A total of 78 patients were identified. Of the 78 patients, 24 (31%) had had celiac dissections, 51 (65%) had had SMA dissections, and 3 (4%) had had both celiac and SMA dissections. The mean age was 57.7 years (range, 36-84 years), with a male predominance (86%). More than one half (55%) of the patients had had hypertension. In addition, 29 patients (37%) were symptomatic, and 24 (31%) had been admitted to the hospital. The symptomatic patients with celiac axis dissections were more likely to have thrombosis (P = .02), significant stenosis (P = .01) or branch extension (P = .02). The symptomatic patients with SMA dissections were more likely to have a smaller artery diameter (P = .07), a longer dissection length (P = .05), thrombosis (P < .001), significant stenosis (P < .001), or branch extension (P = .003). The symptomatic patients were more likely to have been treated with antiplatelet or anticoagulant therapy (P < .001). Only three patients had undergone an intervention. Seven patients (9%) had died of unrelated causes. The Kaplan-Meier survival analysis showed a 5-year survival rate of 96% and 10-year survival rate of 91%. CONCLUSIONS: IMAD is an uncommon disease entity with a risk of visceral ischemia. Nonetheless, most of these patients can be treated conservatively with medication, with only a small minority requiring emergency surgery.


Assuntos
Artéria Mesentérica Superior , Trombose , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Artéria Mesentérica Superior/diagnóstico por imagem , Artéria Mesentérica Superior/cirurgia , Constrição Patológica , Fatores de Risco , Resultado do Tratamento , Artéria Celíaca/diagnóstico por imagem , Artéria Celíaca/cirurgia , Estudos Retrospectivos
8.
J Vasc Surg ; 78(4): 929-935.e1, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37330148

RESUMO

OBJECTIVE: There is no proven therapy to reduce growth rates of small- to medium-sized abdominal aortic aneurysms (AAAs). Ex vivo and animal studies have demonstrated that a novel stabilizing agent, 1,2,3,4,6-pentagalloyl glucose (PGG), delivered locally to the aneurysm sac, can bind to elastin and collagen to re-establish strength and resist enzymatic degradation. We aimed to demonstrate that a one-time administration of PGG solution to the aneurysm wall is safe and potentially effective to slow the growth of small- to medium-sized AAAs. METHODS: Patients with small- to medium-sized infrarenal AAAs (maximum diameter <5.5 cm) were recruited. Via transfemoral access, a 14F or 16F dual-balloon delivery catheter was introduced into the aneurysm sac. A single, 3-minute, localized endoluminal infusion of PGG was delivered via a 'weeping' balloon to the aneurysm wall. Independent core laboratory measurements of maximum aneurysm sac diameter and sac volume measurements based on computed tomography angiography (CTA) were used for assessments at 1, 6, 12, 24, and 36 months. The primary endpoints were technical success and safety (major adverse events at 30 days). The secondary endpoint was growth stabilization, defined as freedom from aneurysm sac enlargement (diameter increase >5 mm per year or volume increase of >10% per year). RESULTS: Twenty patients (19 male) were enrolled at five centers from May 2019 to June 2022 (mean age, 67.8 years; range, 50-87 years). All procedures were technically successful. The safety profile was consistent with standard interventional procedures. Four patients demonstrated transient elevations of liver enzymes levels that returned to normal by 30 days with no clinical symptoms. Through November 2022, follow-up CTA data is available on the first 11 patients. The average changes in maximum aneurysm diameter from baseline to 6, 12, 24, and 36 months were 0.2 mm, 1.1 mm, 1.2 mm, and 0.8 mm, respectively, and the average changes in volume were 2.0%, 9.6%, 18.1%, and 11.6%, respectively. At 12 months, none of the aneurysms showed growth >5.0 mm, and three had volume growth >10%. CONCLUSIONS: The early results of this first-in-human, small cohort study demonstrated that a single, localized PGG administration to patients with small- to medium-sized infrarenal AAAs is safe. Longer term follow-up on all 20 treated patients is needed to better assess the potential impact on aneurysm growth.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Masculino , Idoso , Projetos Piloto , Estudos de Coortes , Aorta Abdominal , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/etiologia , Tomografia Computadorizada por Raios X , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Resultado do Tratamento , Prótese Vascular , Desenho de Prótese
9.
Chemistry ; 29(63): e202302352, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37584964

RESUMO

In expanding our research activities of superlattice engineering, designing new giant molecules is the necessary first step. One attempt is to use inorganic transition metal clusters as building blocks. Efficient functionalization of chemically precise transition metal clusters, however, remains a great challenge to material scientists. Herein, we report an efficient thiol-Michael addition approach for the modifications of cyclic titanium-oxo cluster (CTOC). Several advantages, including high efficiency, mild reaction condition, capability of complete addition, high atom economy, as well as high functional group tolerance were demonstrated. This approach can afford high yields of fully functionalized CTOCs, which provides a powerful platform for achieving versatile functionalization of precise transition metal clusters and further applications.

10.
J Endovasc Ther ; 30(4): 561-570, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35466774

RESUMO

PURPOSE: Ascending aortic replacement is a common emergency procedure for treating acute type A aortic dissection. Secondary open or endovascular interventions for residual arch pathologies is difficult because of adhesions, short prosthetic grafts, and distorted anatomies. Aortic arch branched stent grafts have emerged as a potential solution for these patients if they have suitable anatomical conditions. This study aimed to evaluate the theoretical anatomical and technical feasibility of 2 currently used aortic arch branch endografts in patients who had prior replacement of the ascending aorta. MATERIALS AND METHODS: All patients who had a prosthetic ascending aortic or hemiarch replacement for acute type A dissection in a single institution between January 2013 and December 2018 were included. Contrast computed tomography images on the most recent follow-up were analyzed on a 3-dimensional workstation. Morphological parameters were measured individually for the ascending aorta, aortic arch, supra-aortic branches, and access iliac arteries. The computed tomography scan of each patient was individually evaluated for anatomical suitability for the arch branched and double-branch devices according to set selection criteria. RESULTS: Computed tomography images of 56 patients (median age of 57 years, 45 males) were reviewed. Based on our evaluation, 26 patients (46.4%) were good candidates for an endovascular arch branched device. It would be feasible for 13 patients (23.2%), but prudent preoperative planning was required due to complicated anatomy. The other 17 patients (30.4%) were unsuitable because they met at least 1 exclusion criterion. Short prosthetic grafts, extreme graft angulations, and extensive dissections in the supra-aortic branches were the main reasons for exclusion. CONCLUSION: Endovascular repair using arch branched endografts is feasible in patients with prior ascending aortic arch or hemiarch replacement for acute type A aortic dissection. The most common anatomical conditions that may influence the feasibility of the arch branched endograft procedure include insufficient proximal seal length, severe angulation of the graft, and extensive aortic dissection within the supra-aortic vessels.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Masculino , Humanos , Pessoa de Meia-Idade , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/etiologia , Estudos de Viabilidade , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Desenho de Prótese , Estudos Retrospectivos , Stents , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia
11.
J Endovasc Ther ; : 15266028231197395, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37646117

RESUMO

OBJECTIVE: To provide a descriptive overview on the contemporary outcomes of thoracic endovascular arch repair with inner branched endoprosthesis (bTEVAR) for the treatment of aortic arch pathologies. METHODS: A comprehensive literature search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Pre-defined search terms were used to interrogate PubMed and OVID Medline databases from January 1999 to July 2022. Patient characteristics, indication for treatment, procedural data, mortality rates, postoperative complications, and reintervention rate during follow-up were evaluated. RESULTS: Nineteen articles were included, encompassing a total of 618 patients who received bTEVAR, most of which were double-branched (63.9%, n=395). The main indication for treatment was aneurysm secondary to chronic aortic dissection (38.8%, n=240/618) with a mean maximum diameter of 58.3±11.4 mm. Pooled mean technical success rate was 97.4±4.4% (95% confidence interval [CI]=95.1%-99.5%); 2 and 3 patients required conversion to chimney technique and open repair, respectively. Among the pooled rates of early complications, postoperative stroke was the highest (10.5%; 95% CI=6.8%-14.3%). Thirty-day and in-hospital mortality rate was 5.5% (95% CI=2.6%-9.7%). Forty patients (6.5%; 95% CI=2.5%-9.5%) required early reintervention. During a mean follow-up of 20.7±13.5 months, the mortality rate was 18.2% (n=108/593; 95% CI=8.6%-20.6%) where 12 (11.1%) were aortic-related. Pooled late reintervention rate was 9.6% (95% CI=4.8%-14.3%). Comparison of demographics and outcomes found no significant difference between single and double bTEVAR. CONCLUSION: Branched thoracic endovascular aortic repair is a promising approach for aortic arch pathologies with a high technical success rate despite a steep learning curve. However, contemporary outcomes reflect that postoperative stroke remains the predominant concern. Further experience and long-term follow-up are required to sufficiently elucidate the safety and durability of bTEVAR in the management of aortic pathologies for high-risk patients. CLINICAL IMPACT: This systematic review summarized the contemporary outcomes of thoracic endovascular aortic repair with different inner branched stent-grafts for the management of aortic arch pathologies. Pooled results from nineteen studies with 618 patients demonstrated a high technical success rate and an acceptable mortality rate. However, postoperative stroke remains the major concern. Long-term follow-up is needed to evaluate its durability.

12.
Macromol Rapid Commun ; 44(1): e2200216, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35557023

RESUMO

Three sets of polyoxometalate (POM)-based amphiphilic hybrid macromolecules with different rigidity in their organic tails are used as models to understand the effect of molecular rigidity on their possible self-recognition feature during self-assembly processes. Self-recognition is achieved in the mixed solution of two structurally similar, sphere-rigid T-shape-linked oligofluorene(TOF4 ) rod amphiphiles, with the hydrophilic clusters being Anderson (Anderson-TOF4 ) and Dawson (Dawson-TOF4 ), respectively. Anderson-TOF4 is observed to self-assemble into onion-like multilayer structures and Dawson-TOF4 forms multilayer vesicles. The self-assembly is controlled by the interdigitation of hydrophobic rods and the counterion-mediated attraction among charged hydrophilic inorganic clusters. When the hydrophobic blocks are less rigid, e.g., partially rigid polystyrene and fully flexible alkyl chains, self-recognition is not observed, attributing to the flexible conformation of hydrophobic molecules in the solvophobic domain. This study reveals that the self-recognition among amphiphiles can be achieved by the geometrical limitation of the supramolecular structure due to the rigidity of solvophobic domains.


Assuntos
Micelas , Substâncias Macromoleculares/química , Conformação Molecular , Interações Hidrofóbicas e Hidrofílicas
13.
Ann Vasc Surg ; 89: 261-268, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36162626

RESUMO

BACKGROUND: The aim of this study is to review long-term outcome and identify risk factors for patients with peripheral arterial disease (PAD) with percutaneous transluminal angioplasty/stent as a primary treatment strategy for intermittent claudication (IC) or chronic limb-threatening ischemia (CLTI). METHODS: A retrospective cohort study with data collected prospectively from Clinical Data Analysis and Reporting System, departmental database, and Clinical Management System. All patients who underwent endovascular procedures for PAD between January 2011 and December 2020 were identified. The primary outcomes are overall survival and amputation-free survival. Predictive factors for OS and AFS were determined using Cox Model. RESULTS: A total number of 640 patients with PAD (IC, n = 243; CLTI, n = 377) underwent endovascular percutaneous transluminal angioplasty/stenting for PAD from January 2011 to December 2020. Patients with CLTI had a significantly higher 30 days readmission rate (18.8% vs. 6.5%, P < 0.001), emergency reoperation within 30 days (3.4% vs. 0%, P = 0.002), and death within same admission (2.7% vs. 0%, P = 0.008) compared to IC patients. The overall survival and amputation-free survival rates were significantly lower in CLTI patients (P < 0.0001 and P < 0.0001, respectively). On Cox multivariate analysis, CLTI was strongly predictive of all-cause mortality and amputation (hazard ratio [HR] 2.33 and HR 14.92, respectively). In patients with CLTI, chronic kidney disease was an independent predictor of mortality and amputation (HR 1.66 and HR 2.36, respectively). Smoking and ischemic heart disease were also independent predictors of mortality in this subgroup (HR 2.06 and HR 2.43, respectively). CONCLUSIONS: Although patients with IC and CLTI both manifest from atherosclerotic occlusive disease of the lower limb arteries, these patients may have different clinical outcomes with significant mortality occurred in both IC and CLTI groups. In patients with IC, the risk of amputation was less than 1% at 5 years following revascularization.


Assuntos
Procedimentos Endovasculares , Doença Arterial Periférica , Humanos , Claudicação Intermitente/diagnóstico por imagem , Claudicação Intermitente/terapia , Isquemia Crônica Crítica de Membro , Estudos Retrospectivos , Salvamento de Membro , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Resultado do Tratamento , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Fatores de Risco , Doença Crônica
14.
Lab Invest ; 102(2): 194-203, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34625658

RESUMO

Glioblastoma (GBM) is the most malignant primary tumor in the central nervous system of adults. Temozolomide (TMZ), an alkylating agent, is the first-line chemotherapeutic agent for GBM patients. However, its efficacy is often limited by innate or acquired chemoresistance. Cancer cells can rewire their metabolic programming to support rapid growth and sustain cell survival against chemotherapies. An example is the de novo serine synthesis pathway (SSP), one of the main branches from glycolysis that is highly activated in multiple cancers in promoting cancer progression and inducing chemotherapy resistance. However, the roles of SSP in TMZ therapy for GBM patients remain unexplored. In this study, we employed NCT503, a highly selective inhibitor of phosphoglycerate dehydrogenase (PHGDH, the first rate-limiting enzyme of SSP), to study whether inhibition of SSP may enhance TMZ efficacy in MGMT-positive GBMs. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flowcytometry and colony formation assays demonstrated that NCT503 worked synergistically with TMZ in suppressing GBM cell growth and inducing apoptosis in T98G and U118 cells in vitro. U118 and patient-derived GBM subcutaneous xenograft models showed that combined NCT503 and TMZ treatment inhibited GBM growth and promoted apoptosis more significantly than would each treatment alone in vivo. Mechanistically, we found that NCT503 treatment decreased MGMT expression possibly by modulating the Wnt/ß-catenin pathway. Moreover, intracellular levels of reactive oxygen species were elevated especially when NCT503 and TMZ treatments were combined, and the synergistic effects could be partially negated by NAC, a classic scavenger of reactive oxygen species. Taken together, these results suggest that NCT503 may be a promising agent for augmenting TMZ efficacy in the treatment of GBM, especially in TMZ-resistant GBMs with high expression of MGMT.


Assuntos
Neoplasias Encefálicas/metabolismo , Dano ao DNA , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Glioblastoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina/biossíntese , Temozolomida/farmacologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Sinergismo Farmacológico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Piperazinas/farmacologia , Piridinas/farmacologia , Serina/antagonistas & inibidores , Tioamidas/farmacologia , Carga Tumoral/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
Angew Chem Int Ed Engl ; 61(28): e202203433, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35478477

RESUMO

The hierarchical self-assembly process opens up great potential for the construction of nanostructural superlattices. Precise regulation of self-assembled superlattices, however, remains a challenge. Even when the primary molecules are precise, the supramolecular motifs (or secondary building blocks) can vary dramatically. In the present work, we propose the concept of unimolecular nanoparticles (UMNPs). The UMNPs act as the supramolecular motif and directly pack into the superlattices. A highly branched giant molecule is presented. We systematically explore its conformations and the superlattice of this giant molecule. Moreover, intriguing complex phases are discovered when blending this UMNP with other conventional giant molecules. These binary mixtures provide direct evidence to support our previously proposed self-sorting process in the self-assembly of "soft alloys". The concept of UMNPs offers a unique approach toward more precise regulation of self-assembled superlattices in soft matter.

16.
Angew Chem Int Ed Engl ; 61(19): e202200637, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35174943

RESUMO

The packing structures of spherical motifs affect the properties of resultant condensed materials such as in metal alloys. Inspired by the classic metallurgy, developing complex alloy-like packing phases in soft matter (also called "soft alloys") is promising for the next-generation superlattice engineering. Nevertheless, the formation of many alloy-like phases in single-component soft matter is usually thermodynamically unfavourable and technically challenging. Here, we utilize a novel self-sorting assembly approach to tackle this challenge in binary blends of soft matter. Two types of giant shape amphiphiles self-sort to form their discrete spherical motifs, which further simultaneously pack into alloy-like phases. Three unconventional spherical packing phases have been observed in these binary systems, including MgZn2 , NaZn13 , and CaCu5 phases. It's the first time that the CaCu5 phase is experimentally observed in soft matter. This work demonstrates a general approach to constructing unconventional spherical packing phases and other complex superlattices in soft matter.

17.
J Am Chem Soc ; 143(37): 15319-15325, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34506155

RESUMO

Multicomponent crystallization is universally important in various research fields including materials science as well as biology and geology, and presents new opportunities in crystal engineering. This process includes multiple kinetic and thermodynamic events that compete with each other, wherein "external triggers" often help the system select appropriate pathways for constructing desired structures. Here we report an unprecedented finding that a lattice strain accumulated with the growth of a crystal serves as an "internal trigger" for pathway selection in multicomponent crystallization. We discovered a "spontaneous" crystal transition, where the kinetically preferred layered crystal, initially formed by excluding the pillar component, carries a single dislocation at its geometrical center. This crystal "spontaneously" liberates a core region to relieve the accumulated lattice strain around the dislocation. Consequently, the liberated part becomes dynamic and enables the pillar ligand to invade the crystalline lattice, thereby transforming into a thermodynamically preferred pillared-layer crystal.

18.
J Am Chem Soc ; 143(51): 21613-21621, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34913335

RESUMO

Correlating nanoscale building blocks with mesoscale superlattices, mimicking metal alloys, a rational engineering strategy becomes critical to generate designed periodicity with emergent properties. For molecule-based superlattices, nevertheless, nonrigid molecular features and multistep self-assembly make the molecule-to-superlattice correlation less straightforward. In addition, single component systems possess intrinsically limited volume asymmetry of self-assembled spherical motifs (also known as "mesoatoms"), further hampering novel superlattices' emergence. In the current work, we demonstrate that properly designed molecular systems could generate a spectrum of unconventional superlattices. Four categories of giant molecules are presented. We systematically explore the lattice-forming principles in unary and binary systems, unveiling how molecular stoichiometry, topology, and size differences impact the mesoatoms and further toward their superlattices. The presence of novel superlattices helps to correlate with Frank-Kasper phases previously discovered in soft matter. We envision the present work offers new insights about how complex superlattices could be rationally fabricated by scalable-preparation and easy-to-process materials.

19.
J Am Chem Soc ; 143(33): 12935-12942, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387467

RESUMO

We report the preparation of hexagonal mesoporous silica from single-source giant surfactants constructed via dihydroxyl-functionlized polyhedral oligomeric silsesquioxane (DPOSS) heads and a polystyrene (PS) tail. After thermal annealing, the obtained well-ordered hexagonal hybrid was pyrolyzed to afford well-ordered mesoporous silica. A high porosity (e.g., 581 m2/g) and a uniform and narrow pore size distribution (e.g., 3.3 nm) were achieved. Mesoporous silica in diverse shapes and morphologies were achieved by processing the precursor. When the PS tail length was increased, the pore size expanded accordingly. Moreover, such pyrolyzed, ordered mesoporous silica can help to increase both efficiency and stability of nanocatalysts.

20.
Ann Surg ; 273(5): 997-1003, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30973389

RESUMO

OBJECTIVE: The objective of this study was to evaluate the outcome of endovascular aortic arch repair for chronic dissection with a custom-made branched endograft. BACKGROUND: Acute type A aortic dissections are often treated with prosthetic replacement of the ascending aorta. During follow-up, repair of an aneurysmal evolution of the false lumen distal to the ascending prosthesis can be a challenge both for the surgeon and the patient. METHODS: We conducted a multicenter, retrospective study of consecutive patients from 14 vascular units treated with a custom-made, inner-branched device (Cook Medical, Bloomington, IN) for chronic aortic arch dissection. Rates of in-hospital mortality and stroke, technical success, early and late complications, reinterventions, and mortality during follow-up were evaluated. RESULTS: Seventy consecutive patients were treated between 2011 and 2018. All patients were considered unfit for conventional surgery. In-hospital combined mortality and stroke rate was 4% (n = 3), including 1 minor stroke, 1 major stroke causing death, and 1 death following multiorgan failure. Technical success rate was 94.3%. Twelve (17.1%) patients required early reinterventions: 8 for vascular access complication, 2 for endoleak correction, and 2 for pericardial effusion drainage. Median follow-up was 301 (138-642) days. During follow-up, 20 (29%) patients underwent secondary interventions: 9 endoleak corrections, 1 open repair for prosthetic kink, and 10 distal extensions of the graft to the thoracic or thoracoabdominal aorta. Eight patients (11%) died during follow-up because of nonaortic-related cause in 7 cases. CONCLUSIONS: Endovascular treatment of aortic arch chronic dissections with a branched endograft is associated with low mortality and stroke rates but has a high reintervention rate. Further follow-up is required to confirm the benefits of this novel approach.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/mortalidade , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico , Aneurisma da Aorta Torácica/mortalidade , Doença Crônica , Angiografia por Tomografia Computadorizada , Feminino , Seguimentos , Saúde Global , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
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