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1.
J Am Chem Soc ; 146(7): 4993-5004, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38333965

RESUMO

Alkyne hydrogenation on palladium-based catalysts modified with silver is currently used in industry to eliminate trace amounts of alkynes in alkenes produced from steam cracking and alkane dehydrogenation processes. Intensive efforts have been devoted to designing an alternative catalyst for improvement, especially in terms of selectivity and catalyst cost, which is still far away from that as expected. Here, we describe an atomic design of a high-performance Ni-based intermetallic catalyst aided by active machine learning combined with density functional theory calculations. The engineered NiIn catalyst exhibits >97% selectivity to ethylene and propylene at the full conversion of acetylene and propyne at mild temperature, outperforming the reported Ni-based catalysts and even noble Pd-based ones. Detailed mechanistic studies using theoretical calculations and advanced characterizations elucidate that the atomic-level defined coordination environment of Ni sites and well-designed hybridization of Ni 3d with In 5p orbital determine the semihydrogenation pathway.

2.
Angew Chem Int Ed Engl ; : e202410979, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967363

RESUMO

Catalytic removal of alkynes is essential in industry for producing polymer-grade alkenes from steam cracking processes. Non-noble Ni-based catalysts hold promise as effective alternatives to industrial Pd-based catalysts but suffer from low activity. Here we report embedding of single-atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well-defined synthesis strategy to design Pd1-NiGa catalyst for alkyne semi-hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96% than the state-of-the-art catalysts under industry-relevant conditions. Integrated experimental and computational studies reveal that the single-atom Pd located synergizes with the neighbouring Ni sites to facilitate the σ-adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single-atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi-hydrogenation, providing an effective strategy for stimulating low active Ni-based catalysts for other selective hydrogenations in industry.

3.
J Am Chem Soc ; 145(41): 22836-22844, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37794780

RESUMO

Mixed plastic waste treatment has long been a significant challenge due to complex composition and sorting costs. In this study, we have achieved a breakthrough in converting mixed plastic wastes into a single chemical product using our innovative single-atom catalysts for the first time. The single-atom Ru catalyst can convert ∼90% of real mixed plastic wastes into methane products (selectivity >99%). The unique electronic structure of Ru sites regulates the adsorption energy of mixed plastic intermediates, leading to rapid decomposition of mixed plastics and superior cycle stability compared to traditional nanocatalysts. The global warming potential of the entire process was evaluated. Our proposed carbon-reducing process utilizing single-atom catalysts launches a new era of mixed plastic waste valorization.

4.
Chin J Physiol ; 66(1): 43-51, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814156

RESUMO

Prostate cancer (PCa) is one of the leading causes of cancer-related death in males worldwide and exploring more reliable biomarkers for PCa is essential for the diagnosis and therapeutics for the disease. Although the functions of miR-141-3p and AlkB homolog 5 (ALKBH5) were identified in some cancers, whether they were involved in the development of PCa remains unclear. In this study, reverse transcription-quantitative polymerase chain reaction unveiled that the expression of ALKBH5 was reduced in PCa tissues and was negatively correlated with miR-141-3p. ALKBH5 attenuated the malignant development of PCa through suppressing the growth, migration, invasion, and sphere formation abilities of PCa cells. In addition, the luciferase activity assay identified that ALKBH5 was corroborated as a downstream target of miR-141-3p. Moreover, miR-141-3p expression was boosted in PCa tissues and cells and inhibition of miR-141-3p suppressed the tumor growth of PCa in vivo. Moreover, ALKBH5 was confirmed to suppress protein arginine methyltransferase 6 (PRMT6) expression through N6-methyladenosine (m6A) modification. We further identified that miR-141-3p-modulated PRMT6 level through mediating ALKBH5. Furthermore, PRMT6 level was positively correlated with miR-141-3p level and negatively associated with ALKBH5 level. Finally, rescue assays also uncovered that miR-141-3p aggravated PCa development by regulating PRMT6. In conclusion, miR-141-3p accelerated the malignant progression of PCa through ALKBH5-mediated m6A modification of PRMT6, which might offer a novel insight into the role of miR-141-3p and ALKBH5 in the treatments of PCa patients.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase , MicroRNAs , Proteínas Nucleares , Neoplasias da Próstata , Proteína-Arginina N-Metiltransferases , Humanos , Masculino , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
5.
J Endovasc Ther ; 29(1): 32-41, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34727761

RESUMO

PURPOSE: The purpose of this study was to evaluate the association between the distance from the primary intimal tear (PIT) to the left subclavian artery (LSA) (PIT-LSA distance) and the risk of aortic enlargement after thoracic endovascular aortic repair (TEVAR). METHODS: This is a retrospective cohort study. A total of 228 patients were reviewed from the database of the Registry Of type B aortic dissection with the Utility of STent graft (ROBUST) study performed from January 1, 2011, to December 31, 2016. Of them, 196 patients were eligible for analysis. The PIT-LSA distance was defined as the length from the distal edge of the LSA orifice to the proximal edge of the PIT along the centerline of the true lumen. According to the border between zone 3 and zone 4 of the Ishimaru classification, patients were divided into group A (n = 117, PIT-LSA distance ≤ 2 cm) and group B (n = 79, PIT-LSA distance > 2 cm). Thoracic aortic enlargement (TAE) was defined as a thoracic aortic volume increase of ≥20%. Multivariate Cox regression was used to estimate the association between the PIT-LSA distance and risk of TAE after TEVAR. RESULTS: The mean age was 52.3 ± 11.6 years, and 88.8% of patients were male. There were no significant differences between groups in demographic and baseline characteristics. The PIT-LSA distance was 1.1 cm (range, -1.6 to 2.0 cm) in group A, and 2.9 cm (range, 2.1-12.6 cm) in group B. TAE occurred in 27 patients in group A, and 6 in group B. The mean follow-up was 12.4 months (range, 0.10-83.1 months) in group A, and 12.63 months (range, 0.10-82.77 months) in group B. The cumulative 12- and 24-month rates of freedom from TAE were 79.0% and 71.3% in group A, versus 92.5% and 92.5% in group B, respectively. Multivariate Cox regression analysis revealed that the PIT-LSA distance was an independent predictor of TAE after TEVAR (adjusted hazard ratio, 0.66; 95% confidence interval, 0.48-0.90; p = 0.009). CONCLUSION: Patients with a more proximal PIT location have a higher incidence of thoracic aortic enlargement after TEVAR. The location of the PIT in relation to the LSA can be used to identify patients who need closed surveillance after TEVAR or early preemptive intervention.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia , Fatores de Tempo , Resultado do Tratamento
6.
Angew Chem Int Ed Engl ; 61(51): e202215225, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36269685

RESUMO

Precisely tailoring the distance between adjacent metal sites to match adsorption configurations of key species for the targeted reaction pathway is a great challenge in heterogeneous catalysis. Here, we report a proof-of-concept study on the atomically sites-tailored pathway in Pd-catalyzed acetylene hydrogenation, i.e., increasing the distance of adjacent Pd atoms (dPd-a-Pd ) for configuration matching in acetylene semi-hydrogenation against coupling. dPd-a-Pd is identified as a structural descriptor for describing the competitiveness for reaction pathways, and the increased dPd-a-Pd prefers the semi-hydrogenation pathway due to simultaneously promoted C2 H4 desorption and the destabilized transition state of the C2 H3 * coupling. Spectroscopic, kinetics and electronic structure studies reveal that increasing dPd-a-Pd to 3.31 Šdelivers superior selectivity and stability due to energy matching and appropriate hybridization of Pd 4d with In 2s and, especially, 2p orbitals.

7.
Ann Vasc Surg ; 77: 288-295, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34416282

RESUMO

BACKGROUND: This study is to investigate the role and mechanism of mir-5189-3p in deep vein thrombosis (DVT) in lower extremity. METHODS: The blood samples were collected from Kazakh patients with DVT in lower extremity and were subjected to microRNA sequencing. Bioinformatics were used to identify mir-5189-3p and its target genes. Dual luciferase reporter assay was used to determine the regulatory effect of mir-5189-3p on JAG1. SD rats were randomly divided into normal control, DVT model, hsa-miR-5189-3p mimics and hsa-miR-5189-3p negative control groups. HE staining was used to observe the pathological changes. TUNEL method was used to observe apoptosis. Western blot was used to detect Bax and Bcl-2 protein expression. Real-time quantitative PCR was used to detect JAG1, Notch1 and Hes1 mRNA. RESULTS: The target of Has-miR-5189-3p was JAG1. Co-transfection of miR-5189-3p mimics and pmirGLO/JAG1 wild-type plasmid induced significantly decreased luciferase activity. In hsa-miR-5189-3p mimics and hsa-miR-5189-3p negative control groups, there were more nucleated cells in the thrombus tissues, and the organization degree obviously increased. Signs of blood flow recanalization were observed. The apoptosis of hsa-miR-5189-3p mimics and hsa-miR-5189-3p negative control groups was lower than that in DVT model group. Furthermore, mir-5189-3p mimics significantly increased the mRNA levels of JAG1, Notch1 and Hes1. Additionally, mir-5189-3p mimics significantly increased Bcl-2 while decreased Bax protein. CONCLUSIONS: mir-5189-3p could inhibit apoptosis and promote thrombus organization in DVT possibly via Notch signaling pathway. Mir-5189-3p can be used as a potential target for DVT treatment.


Assuntos
MicroRNAs/metabolismo , Veia Cava Inferior/metabolismo , Trombose Venosa/metabolismo , Animais , Apoptose , Modelos Animais de Doenças , Células HEK293 , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , MicroRNAs/sangue , MicroRNAs/genética , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Receptor Notch1/genética , Receptor Notch1/metabolismo , Transdução de Sinais , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , Veia Cava Inferior/patologia , Trombose Venosa/sangue , Trombose Venosa/genética , Trombose Venosa/patologia , Proteína X Associada a bcl-2/metabolismo
8.
Ann Vasc Surg ; 71: 56-64, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32949748

RESUMO

BACKGROUND: Abdominal aortic enlargement (AAE) is a commonly seen complication after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). This study assessed the relationship between preoperative abdominal false lumen-perfused small branches (pre-AFLSBs) and risk of AAE after TEVAR for TBAD extending through the abdominal aorta. METHODS: One hundred and eighty-four patients with TBAD who had been treated by TEVAR at 4 hospitals in China were stratified in accordance with median pre-AFLSBs: ≤8 (group A) and >8 (group B). AAE was defined as ≥20% increase in abdominal total aortic volume, measured using imaging software featuring centerline analysis, on most recent postoperative computed tomography angiography relative to preoperative examination. Multivariable Cox proportional hazard regression was used to evaluate the relationship between the number of pre-AFLSBs and the risk of AAE after TEVAR. RESULTS: At median 12.4 months imaging follow-up, AAE was present in 65 patients at higher cumulative rate (log-rank test P < 0.001) in group B, which had more frequent partially thrombosed or patent abdominal false lumen than group A at 6-12 months (P < 0.01) and 12-24 months (P = 0.03) of follow-up. In a multivariable Cox proportional hazard regression model, the number of pre-AFLSBs was independently associated with risk of AAE after TEVAR (hazard ratio [for one increase], 1.10; 95% confidence interval, 1.00-1.21; P = 0.04) after adjustment for age, gender, dissection chronicity, Society for Vascular Surgery risk score, preoperative maximum descending aortic diameter, false lumen status of the abdominal aorta, numbers of false lumen-perfused visceral arteries, abdominal intimal larger tears, and preoperative abdominal intimal small tears, and dissection length and descending aortic length ratio. CONCLUSIONS: The number of pre-AFLSBs was positively associated with the risk of AAE after TEVAR for TBAD extending through the abdominal aorta.


Assuntos
Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Remodelação Vascular , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , China , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
Ann Vasc Surg ; 77: 54-62, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34175415

RESUMO

BACKGROUND: This study was performed to evaluate the nonlinear association of the distal oversizing ratio with distal stent-graft-induced new entry (dSINE) following thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) and to find the optimal value of the distal oversizing ratio for prevention strategy of dSINE. METHODS: Total of 177 patients who underwent TEVAR for TBAD from the Registry Of type B aortic dissection with the Utility of STent graft were retrospectively investigated. Patients were stratified into two groups on the median distal oversizing ratio: lower group (≤16%, n = 88) and higher group (>16%, n = 89). The Kaplan-Meier method was used to estimate the cumulative incidence of dSINE. The multivariate Cox proportional hazards model was used to identify the association of the distal oversizing ratio with dSINE. Restricted cubic smoothing spline plots and two-piecewise regression were used to analyze the possible nonlinear association. RESULTS: Eleven patients developed dSINE (6.21%) during the median follow-up time of 12.37 months (interquartile range, 8.07-18.17 months). An S-shaped association of the distal oversizing ratio with dSINE was identified. When the distal oversizing ratio was ≤40%, the risk of dSINE increased with distal oversizing ratio, and the risk of dSINE was highest when the distal oversizing ratio reached 40% (adjusted HR, 1.09; 95% CI, 1.02-1.17; P = 0.011). A larger distal oversizing ratio over 40% did not generate a greater risk of dSINE (adjusted HR, 0.95; 95% CI, 0.87-1.05; P = 0.455). CONCLUSIONS: This study substantiated previous findings that the dSINE was associated with the increasing distal oversizing ratio. We also found an S-shaped association between the distal oversizing ratio and dSINE after TEVAR for TBAD. The distal oversizing ratio of 40% can be used for stratified management of patients who underwent TEVAR for TBAD.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Idoso , Dissecção Aórtica/diagnóstico por imagem , Aneurisma Aórtico/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , China , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Desenho de Prótese , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
10.
J Clin Lab Anal ; 35(3): e23687, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33411343

RESUMO

OBJECTIVE: The aim of the present study was to investigate the expression profiles of circular RNAs (circRNAs) in the pericystic tissue of patients with cystic echinococcosis (CE). PATIENTS AND METHODS: CircRNA expression profiles were obtained by circRNA microarray of four matched pairs of pericystic tissues affected by CE and adjacent normal liver tissues. qRT-PCR was used to validate the differential expression of some circRNAs identified by the microarray analysis. The potential functions of the differentially expressed circRNAs in the CE pericystic tissues were predicted by bioinformatic analysis. RESULTS: Compared with the adjacent normal liver tissues, 177 circRNAs were upregulated and 166 circRNAs were downregulated in CE pericystic tissues based on a ≥2.0-fold change. The top 10 upregulated circRNAs were hsa_circRNA_001654,hsa_circRNA_103361,hsa_circRNA_001490,hsa_circRNA_104310,hsa_circRNA_100395,hsa_circRNA_102485,hsa_circRNA_001459,hsa_circRNA_104193,hsa_circRNA_400043, and hsa_circRNA_006773; The top 10 downregulated circRNAs were hsa_circRNA_400633,hsa_circRNA_404974,hsa_circRNA_068482 ,hsa_circRNA_100974,hsa_circRNA_049637,hsa_circRNA_404798,hsa_circRNA_400064,hsa_circRNA_004045,hsa_circRNA_101379, and hsa_circRNA_016771;The circRNA-seq results for 15 selected differentially expressed circRNAs were validated by qRT-PCR. The qRT-PCR analysis showed that hsa_circRNA_006773, hsa_circRNA_049637, hsa_circRNA_104349, and hsa_circRNA_406281 were differentially expressed in CE pericystic tissues when compared with their expression in the adjacent normal liver tissues. Interestingly, 319 miRNAs and 52 mRNAs were predicted to be adsorbed by these four differentially expressed circRNAs. Gene Ontology analysis revealed that these circRNAs may be involved in the response to organic cyclic compounds and endogenous stimuli and in cellular organismal processes. CONCLUSION: Differential expression of circRNAs may be associated with the development and progression of CE, and these circRNAs might be useful as biomarkers for prognosis prediction and as treatment targets.


Assuntos
Equinococose/genética , RNA Circular/genética , Transcriptoma , Adulto , Equinococose/etiologia , Feminino , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Masculino , Pessoa de Meia-Idade , RNA Circular/análise , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
IEEE Trans Wirel Commun ; 20(2)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34248424

RESUMO

One of the biggest problems facing future mobile systems beyond 5G (B5G) is the energy dissipation of mobile devices at high data rates. The heat generated by these devices can impact the performance as a result of a new type of outage called power-consumption outage. In this article, we propose a general definition of the power-consumption outage and describe its three features. Based on the heat transfer model in smartphones, the power-consumption outage probability is analyzed. Specifically, we derive the joint outage probability of channel and power-consumption outages in relation to the signal-to-noise ratio (SNR), communication duration, and initial temperature of the smartphone-back-plate. The joint outage probability is then used to obtain the upper bound of the maximum receiving rate of a typical smartphone. Furthermore, we propose and analyze the impact on the capacity of the power-consumption outage. Simulation results show that the power-consumption outage probability increases with an increase of SNR and with extension of the communication duration. The upper bound of the maximum receiving rate of a smartphone decreases with an extension of communication duration. Considering the joint outage probability, simulation results show that the outage capacities, i.e., channel and power-consumption outages, decrease with an increase of SNR after reaching a given capacity threshold.

12.
J Endovasc Ther ; 27(2): 211-220, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32026762

RESUMO

Purpose: To examine the association between the extent of stent-graft coverage and thoracic aortic expansion after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection. Materials and Methods: A retrospective analysis was conducted of 201 patients (mean age 52.4±11.5 years; 178 men) with acute (135, 67.2%) or chronic (66, 32.8%) type B aortic dissection who underwent TEVAR at 4 medical centers. The mean stent-graft length was 157.1±33.3 mm. The percentage of stented descending aorta (PSDA) represented the extent of stent-graft coverage. After using restricted cubic smoothing spline plots to confirm the roughly linear relationship between PSDA and the risk of thoracic aortic expansion, patients were stratified into 2 groups on the median PSDA: the lower group (≤31.3%) and the higher group (>31.3%). Thoracic aortic expansion was defined as a ≥20% increase in the total thoracic aortic volume on the most recent postoperative computed tomography angiography scan compared with the preoperative measurement. The Kaplan-Meier method was used to estimate the cumulative freedom from thoracic aortic expansion after TEVAR; estimates are given with the 95% confidence interval (CI). A multivariable Cox proportional hazards model was used to analyze any independent association of the PSDA as a continuous or categorical variable with the risk of thoracic aortic expansion; results are presented as the hazard ratio (HR) and 95% CI. Results: No patients developed symptoms of spinal cord ischemia during hospitalization. Over a median 12.4 months of imaging follow-up, 34 (16.9%) patients developed thoracic aortic expansion. The estimate of freedom from thoracic aortic expansion at 12 months for the overall PSDA was 84.0% (95% CI 77.8% to 88.6%); between the groups, the freedom from thoracic aortic expansion estimate for the PSDA ≤31.3% group was significantly lower than in the higher group (p=0.032). Regression analysis showed no significant association between the risk of thoracic aortic expansion and the PSDA as a continuous variable (HR 0.97, 95% CI 0.91 to 1.03, p=0.288); however, analyzing the PSDA as a categorical variable indicated a significantly lower risk of thoracic aortic expansion for the PSDA >31.3% group (HR 0.46, 95% CI 0.22 to 0.95, p=0.036) after adjusting for a variety of demographic and anatomical characteristics. Conclusion: More extensive stent-graft coverage appears to improve thoracic aortic remodeling after TEVAR. However, the clinician should balance the benefit of extensive stent-graft coverage and its related risk of spinal cord ischemia.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Remodelação Vascular , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , China , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
Ann Vasc Surg ; 65: 289.e1-289.e6, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31866551

RESUMO

Artificial graft infection is one of the most serious complications following EVAR. The gold standard includes the excision of the infected endograft, debridement, and reconstruction. However, these methods are not always the best option for every patient. The authors present the case of a 75-year-old man who was diagnosed with a stent-graft infection following EVAR. A course of antibiotics was administered, and percutaneous drainage was effectively performed twice in succession. After 18 months, the patient was admitted again due to the infection re-occurring. Antibiotics were administered, and percutaneous drainage was effectively re-performed. One year has elapsed since the treatment, and the outpatient followup has lasted until now.


Assuntos
Antibacterianos/uso terapêutico , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Prótese Vascular/efeitos adversos , Drenagem , Procedimentos Endovasculares/efeitos adversos , Infecções Relacionadas à Prótese/terapia , Stents/efeitos adversos , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Implante de Prótese Vascular/instrumentação , Procedimentos Endovasculares/instrumentação , Humanos , Masculino , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Recidiva , Retratamento , Resultado do Tratamento
14.
Ann Vasc Surg ; 67: 316-321, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32209407

RESUMO

BACKGROUND: Distal entry tears have undesirable influence in type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR), including inhibition of aortic remolding and increase of late aortic events. Therefore, distal entry tears should be managed. Nowadays, main strategies for managing distal entry tears included total and selective strategies. However, which strategy is better still remains controversial. The objective of the study is to investigate the outcomes of selective strategy for distal entry tears after TEVAR in TBAD. METHODS: A total of 43 consecutive patients with TBAD with distal entry tears after TEVAR were administered with selective strategy for distal entry tears, including occlusion of the tear in the thoracic aortic segment, thrombosis of the reverse blood flow channel in the false lumen, and selective occlusion of distal entry tears. Mortality, complications, and aortic remolding in early follow-up (12 months after operation) were analyzed. RESULTS: All 43 patients survived during the follow-up period. Operation was performed again for femoral artery reconstruction in 1 patient who had occlusion of the approach vessel during the follow-up period, and the remaining 42 patients had no uncomfortable symptoms and operation-related complications. The maximum diameter of the aorta was 32.03 ± 6.35 mm and 27.36 ± 4.92 mm, respectively, for before and after reintervention, and the difference was significant (t = 5.899, P < 0.001). The unthrombotic range of the false lumen after reintervention was significantly shrunken in all patients, compared with the range before reintervention. CONCLUSIONS: Selective strategy was safe and effective, at least in early follow-up. Its effectiveness should be further verified by more clinical observation results and long-term follow-up results.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Remodelação Vascular
15.
Med Sci Monit ; 24: 9026-9031, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30543205

RESUMO

BACKGROUND To investigate the curative effect and utility of the TurboHawk plaque circumcision system in the treatment of patients with superficial femoral atherosclerosis (SFA). MATERIAL AND METHODS We retrospectively analyzed 60 cases of superficial femoral atherosclerotic stenosis and occlusion treated with the TurboHawk plaque circumcision system for endovascular ablation of the superficial femoral artery in the People's Hospital of Xinjiang Uygur Autonomous Region between January 2016 and December 2017. RESULTS The sample comprised of 50 male and 10 female patients with an average age of 65±4.5 years (range 47 to 70 years). This group of patients had varying degrees of limb ischemia, with disease duration ranging from 1 week to 3 years. The main symptoms included markedly cooler lower-extremity skin temperature, pale and cyanotic, intermittent claudication (10 cases), resting pain (31 cases), distal limb mild ischemic ulcer (14 cases), and tissue ischemic necrosis and gangrene (5 cases). All cases were in stages 3-6 of the Rutherford classification. Almost half (28 patients, 47%) had a significant improvement in their affected limbs and more than half (32 cases, 53%) had a moderate improvement in clinical symptoms after the intervention. After surgery, lumen stenosis decreased and ankle brachial index (ABI) increased significantly (P<0.05). CONCLUSIONS The TurboHawk plaque circumcision system is a feasible and effective method for the treatment of SFA with the advantages of less trauma and better safety, and shows a significant curative effect in a short period.


Assuntos
Técnicas de Ablação/instrumentação , Aterosclerose/terapia , Placa Aterosclerótica/terapia , Técnicas de Ablação/métodos , Idoso , Índice Tornozelo-Braço , China , Constrição Patológica/terapia , Feminino , Artéria Femoral/patologia , Artéria Femoral/cirurgia , Fêmur , Humanos , Masculino , Pessoa de Meia-Idade , Osteonecrose/terapia , Doenças Vasculares Periféricas/terapia , Placa Amiloide , Estudos Retrospectivos , Resultado do Tratamento
16.
Artigo em Inglês | MEDLINE | ID: mdl-31093014

RESUMO

With the growing interest in the deployment of massive multiple-input-multiple-output (MIMO) systems and millimeter wave technology for fifth generation (5G) wireless systems, the computation power to the total power consumption ratio is expected to increase rapidly due to high data traffic processing at the baseband unit. Therefore in this paper, a joint optimization problem of computation and communication power is formulated for multi-user massive MIMO systems with partially-connected structures of radio frequency (RF) transmission systems. When the computation power is considered for massiv MIMO systems, the results of this paper reveal that the energy efficiency of massive MIMO systems decreases with increasing the number of antennas and RF chains, which is contrary with the conventional energy efficiency analysis results of massive MIMO systems, i.e., only communication power is considered. To optimize the energy efficiency of multi-user massive MIMO systems, an upper bound on energy efficiency is derived. Considering the constraints on partially-connected structures, a suboptimal solution consisting of baseband and RF precoding matrices is proposed to approach the upper bound on energy efficiency of multi-user massive MIMO systems. Furthermore, an oPtimized Hybrid precOding with computation and commuNication powEr (PHONE) algorithm is developed to realize the joint optimization of computation and communication power. Simulation results indicate that the proposed algorithm improves energy and cost efficiencies and the maximum power saving is achieved by 76.59% for multi-user massive MIMO systems with partially-connected structures.

17.
Circ Res ; 116(7): e40-50, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25654979

RESUMO

RATIONALE: The mechanism of functional restoration by stem cell therapy remains poorly understood. Novel manganese-enhanced MRI and bioluminescence reporter gene imaging were applied to follow myocardial viability and cell engraftment, respectively. Human-placenta-derived amniotic mesenchymal stem cells (AMCs) demonstrate unique immunoregulatory and precardiac properties. In this study, the restorative effects of 3 AMC-derived subpopulations were examined in a murine myocardial injury model: (1) unselected AMCs, (2) ckit(+)AMCs, and (3) AMC-derived induced pluripotent stem cells (MiPSCs). OBJECTIVE: To determine the differential restorative effects of the AMC-derived subpopulations in the murine myocardial injury model using multimodality imaging. METHODS AND RESULTS: SCID (severe combined immunodeficiency) mice underwent left anterior descending artery ligation and were divided into 4 treatment arms: (1) normal saline control (n=14), (2) unselected AMCs (n=10), (3) ckit(+)AMCs (n=13), and (4) MiPSCs (n=11). Cardiac MRI assessed myocardial viability and left ventricular function, whereas bioluminescence imaging assessed stem cell engraftment during a 4-week period. Immunohistological labeling and reverse transcriptase polymerase chain reaction of the explanted myocardium were performed. The unselected AMC and ckit(+)AMC-treated mice demonstrated transient left ventricular functional improvement. However, the MiPSCs exhibited a significantly greater increase in left ventricular function compared with all the other groups during the entire 4-week period. Left ventricular functional improvement correlated with increased myocardial viability and sustained stem cell engraftment. The MiPSC-treated animals lacked any evidence of de novo cardiac differentiation. CONCLUSION: The functional restoration seen in MiPSCs was characterized by increased myocardial viability and sustained engraftment without de novo cardiac differentiation, indicating salvage of the injured myocardium.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Imageamento por Ressonância Magnética/métodos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Imagem Multimodal , Infarto do Miocárdio/terapia , Miocárdio/patologia , Animais , Separação Celular/métodos , Sobrevivência Celular , Estenose Coronária/complicações , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Genes Reporter , Sobrevivência de Enxerto , Xenoenxertos , Humanos , Ligadura , Medições Luminescentes , Masculino , Manganês , Células-Tronco Mesenquimais/química , Camundongos , Camundongos Mutantes , Camundongos SCID , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Placenta/citologia , Gravidez , Proteínas Proto-Oncogênicas c-kit/análise , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homeostase do Telômero , Função Ventricular Esquerda
18.
J Endovasc Ther ; 24(5): 647-653, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28747077

RESUMO

OVERVIEW: To describe a new endovascular procedure for acute type A aortic dissection (TAAD) repair. METHODS: Between 2013 and 2016, 12 patients (average age 54±9.6 years; 10 men) with acute TAAD (mean EURO score 11.4%±3.2%, range 5-17) and unfit for surgery underwent thoracic endovascular aortic repair (TEVAR) with 2 periscope grafts to preserve blood supply to supra-aortic branches plus bypass grafting as needed. If the ascending aorta was dilated to >40 mm, sternotomy was performed to wrap the ascending aorta and reduce its diameter to accommodate the aortic stent-grafts. RESULTS: All patients were successfully treated. Seven patients required bypass grafting, and most of the patients had periscope grafts to the innominate/right common carotid artery and left common carotid artery; only 3 patients had the left subclavian artery preserved. All patients exhibited good hemodynamics and normal pressures after the procedure. The mean procedure time and blood loss were 4.5±1.0 hours and 217±111.5 mL, respectively. Two patients treated emergently died shortly after surgery from multiorgan failure. The average follow-up duration was 17±14.5 months (range 2-42) in the 10 survivors. The remaining patients recovered and none experienced stent-graft thrombosis, stroke, or peripheral artery embolism during follow-up. CONCLUSION: A procedure that combines sandwich/periscope grafting with TEVAR, wrapping of the aorta, and supra-arch bypass grafting can be used to treat patients with acute TAAD.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Doença Aguda , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/fisiopatologia , Aortografia/métodos , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Fatores de Risco , Fatores de Tempo , Transplantes , Resultado do Tratamento
19.
IEEE Commun Mag ; 55(5): 184-191, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28757670

RESUMO

The deployment of a large number of small cells poses new challenges to energy efficiency, which has often been ignored in fifth generation (5G) cellular networks. While massive multiple-input multiple outputs (MIMO) will reduce the transmission power at the expense of higher computational cost, the question remains as to which computation or transmission power is more important in the energy efficiency of 5G small cell networks. Thus, the main objective in this paper is to investigate the computation power based on the Landauer principle. Simulation results reveal that more than 50% of the energy is consumed by the computation power at 5G small cell base stations (BSs). Moreover, the computation power of 5G small cell BS can approach 800 watt when the massive MIMO (e.g., 128 antennas) is deployed to transmit high volume traffic. This clearly indicates that computation power optimization can play a major role in the energy efficiency of small cell networks.

20.
J Cosmet Dermatol ; 23(4): 1374-1385, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38105431

RESUMO

BACKGROUND: Exosomes are small vesicles released from cells and are found in various mammalian biological fluids, such as bovine milk, which has been employed in skincare for many years, apart from its dairy applications. In addition, exosomes have been recognized as vehicles for intercellular communication. AIMS: In this study, we aimed to investigate the novel effects of bovine milk-derived exosomes (MK-Exo) on antiaging in human skin. METHODS: Initially, MK-Exo were co-cultured with keratinocytes and fibroblasts; subsequent analysis involved qPCR and western blotting to assess induced gene expression. Subsequently, MK-Exo were topically applied to the facial skin of 31 female volunteers twice daily for 28 days. The functions were evaluated after conducting safety assessments in vivo. RESULTS: Purified MK-Exo demonstrated the ability to be taken up directly by keratinocytes and fibroblasts in vitro, resulting in the upregulation of natural factors associated with skin moisturization, including filaggrin (FLG), aquaporin 3 (AQP3), and CD44 in keratinocytes, as well as hyaluronidase (HAS2) in fibroblasts. Concurrently, MK-Exo promoted fibroblast cell migration and restored the expression of type I and III collagen (Col I and Col III) following exposure to ultraviolet radiation. Furthermore, phototoxicity, photoallergy, repeated skin irritation, skin allergy, and patch tests confirmed the safety of MK-Exo for skin application. Finally, we elucidated the roles of MK-Exo in preserving moisture and reducing wrinkles in humans. CONCLUSION: Our findings unveil the novel contributions of MK-Exo to human skin aging, presenting a new avenue in the field of skincare.


Assuntos
Exossomos , Animais , Feminino , Humanos , Exossomos/metabolismo , Raios Ultravioleta/efeitos adversos , Leite , Pele/metabolismo , Queratinócitos , Mamíferos
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