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BACKGROUND AND AIMS: Drug-coated balloons (DCBs) have demonstrated favourable outcomes following endovascular therapy for femoropopliteal artery (FPA) disease. However, uncertainty remains whether the use of intravascular ultrasound (IVUS) can improve the outcomes of DCBs. METHODS: This prospective, multicentre, randomized trial, conducted at seven centres in South Korea, compared the outcomes of IVUS-guided vs. angiography-guided angioplasty for treating FPA disease with DCBs. Patients were assigned to receive IVUS-guided (n = 119) or angiography-guided (n = 118) angioplasty using DCBs. The primary endpoint was 12-month primary patency. RESULTS: Between May 2016 and August 2022, 237 patients were enrolled and 204 (86.0%) completed the trial (median follow-up; 363 days). The IVUS guidance group showed significantly higher primary patency [83.8% vs. 70.1%; cumulative difference 19.6% (95% confidence interval 6.8 to 32.3); P = .01] and increased freedom from clinically driven target lesion revascularization [92.4% vs. 83.0%; difference 11.6% (95% confidence interval 3.1 to 20.1); P = .02], sustained clinical improvement (89.1% vs. 76.3%, P = .01), and haemodynamic improvement (82.4% vs. 66.9%, P = .01) at 12 months compared with the angiography guidance group. The IVUS group utilized larger balloon diameters and pressures for pre-dilation, more frequent post-dilation, and higher pressures for post-dilation, resulting in a greater post-procedural minimum lumen diameter (3.90 ± 0.59 vs. 3.71 ± 0.73 mm, P = .03). CONCLUSIONS: Intravascular ultrasound guidance significantly improved the outcomes of DCBs for FPA disease in terms of primary patency, freedom from clinically driven target lesion revascularization, and sustained clinical and haemodynamic improvement at 12 months. These benefits may be attributed to IVUS-guided optimization of the lesion before and after DCB treatment.
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Angioplastia com Balão , Artéria Femoral , Doença Arterial Periférica , Artéria Poplítea , Ultrassonografia de Intervenção , Grau de Desobstrução Vascular , Humanos , Ultrassonografia de Intervenção/métodos , Masculino , Angioplastia com Balão/métodos , Artéria Femoral/diagnóstico por imagem , Feminino , Artéria Poplítea/diagnóstico por imagem , Doença Arterial Periférica/terapia , Doença Arterial Periférica/diagnóstico por imagem , Estudos Prospectivos , Idoso , Pessoa de Meia-Idade , Materiais Revestidos Biocompatíveis , Resultado do Tratamento , AngiografiaRESUMO
State-of-the-art methods in photoproximity labeling center on the targeted generation and capture of short-lived reactive intermediates to provide a snapshot of local protein environments. Diazirines are the current gold standard for high-resolution proximity labeling, generating short-lived aryl(trifluoromethyl) carbenes. Here, we present a method to access aryl(trifluoromethyl) carbenes from a stable diazo source via tissue-penetrable, deep red to near-infrared light (600-800 nm). The operative mechanism of this activation involves Dexter energy transfer from photoexcited osmium(II) photocatalysts to the diazo, thus revealing an aryl(trifluoromethyl) carbene. The labeling preferences of the diazo probe with amino acids are studied, showing high reactivity toward heteroatom-H bonds. Upon the synthesis of a biotinylated diazo probe, labeling studies are conducted on native proteins as well as proteins conjugated to the Os photocatalyst. Finally, we demonstrate that the conjugation of a protein inhibitor to the photocatalyst also enables selective protein labeling in the presence of spectator proteins and achieves specific labeling of a membrane protein on the surface of mammalian cells via a two-antibody photocatalytic system.
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Proteínas , Luz Vermelha , Animais , Proteínas/química , Metano/química , Diazometano/química , MamíferosRESUMO
Dual-ion batteries (DIBs) are considered one of the promising energy storage devices in which graphite serves as a bi-functional electrode, i.e., anode and cathode in the aprotic organic solvents. Unlike conventional lithium-ion batteries (LIBs), DIBs reversibly store the cations and anions in the anode and cathodes during redox reactions, respectively. The electrolyte is a source for both cations and anions, so the choice of electrolyte plays a vital role. In the present work, the synthesis of SnO2 nanostructures is reported as a possible alternative for graphite anode, and the Li-storage performance is optimized in half-cell (Li/SnO2 ) assembly with varying amounts of conductive additive (acetylene black) and limited working potential (1 V vs Li). Finally, a DIB using recovered graphite (RG) fabricated from spent LIB as a cathode and SnO2 nanostructures as an anode under balanced loading conditions. Prior to the fabrication, both electrodes are pre-cycled to eliminate irreversibility. An in-situ impedance study has been employed to validate the passivation layer formation during the charge-discharge process. The high-performance SnO2 /RG-based DIB delivered a maximum discharge capacity of 380 mAh g-1 . The electrochemical performance of DIB has been assessed by varying temperature conditions to evaluate their suitability in different climatic conditions.
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A novel green-absorbing organic molecule featuring dual intramolecular chalcogen bonds is synthesized and characterized. This molecule incorporates two such bonds: one between a tellurium atom and the oxygen atom of a carbonyl moiety, and the other between the tellurium atom and the adjacent nitrogen atom within a pyridine moiety. The molecule, featuring dual intramolecular chalcogen bonds exhibits a narrow absorption spectrum and elevated absorption coefficients, closely aligned with a resonance parameter of approximately 0.5. This behavior is due to its cyanine-like characteristics and favorable electrical properties, which are a direct result of its rigid, planar molecular structure. Therefore, this organic molecule forming dual intramolecular chalcogen bonds achieves superior optoelectronic performance in green-selective photodetectors, boasting an external quantum efficiency of over 65% and a full-width at half maximum of less than 95 nm while maintaining the performance after 1000 h of heating aging at 85 °C. Such organic photodetectors are poised to enhance stacked organic photodetector-on-silicon hybrid image sensors, paving the way for the next-generation of high-resolution and high-sensitivity image sensors.
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Clinical outcomes after non-ST-segment-elevation myocardial infarction (NSTEMI) in patients with (symptom-to-door time [SDT] ≥ 24 h) or without (SDT < 24 h) delayed hospitalization among patients with or without diabetes were compared. From the Korea Acute Myocardial Infarction Registry-National Institute of Health, a total of 4517 patients with NSTEMI who underwent new-generation drug-eluting stents implantation were recruited and they were classified into the diabetes mellitus (DM) and non-DM groups. These two groups were subdivided into groups with and without delayed hospitalization. The primary clinical outcome was the occurrence of major adverse cardiac and cerebrovascular events (MACCE), defined as all-cause death, recurrent myocardial infarction, repeat coronary revascularization, and stroke. The secondary clinical outcome was the occurrence of individual components of MACCE and stent thrombosis. Although after multivariable and propensity score-adjusted analyses in the DM group, the primary and secondary clinical outcomes between the SDT < 24 h and SDT ≥ 24 h groups were similar; in the non-DM group, all-cause (p = 0.003 and p = 0.007, respectively) and cardiac (p = 0.001 and p = 0.008, respectively) death rates were significantly higher in the SDT ≥ 24 h group than in the SDT < 24 h group. Our results suggested that there was no significant difference in prognosis between diabetic patients with and without delayed SDT, but delayed SDT was associated with poor prognosis in nondiabetic patients.
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Diabetes Mellitus , Stents Farmacológicos , Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Infarto do Miocárdio sem Supradesnível do Segmento ST/etiologia , Resultado do Tratamento , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/terapia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologiaRESUMO
Shape from focus enables microscopic 3D sensing by combining it with a microscope system. However, edge bleeding artifacts of estimated depth easily occur in this environment. Therefore, this study analyzed artifacts and proposed a method to reduce edge bleeding artifacts. As a result of the analysis, the artifact factors are the depth of field of the lens, object texture, brightness difference between layers, and the slope of the object. Additionally, to reduce artifacts, a weighted focus measure value method was proposed based on the asymmetry of local brightness in artifacts. The proposed reduction method was evaluated through simulation and implementation. Edge bleeding artifact reduction rates of up to 60% were shown in various focus measure operators. The proposed method can be used with postprocessing algorithms and reduces edge bleeding artifacts.
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Ultrasonic sensors are inexpensive and provide highly accurate measurements, even with simple hardware configurations, facilitating their use in various fields. When multiple ultrasonic sensors exist in the measurement space, crosstalk occurs due to other nodes, which leads to incorrect measurements. Crosstalk includes not only receiving homogeneous signals from other nodes, but also overlapping by other signals and interference by heterogeneous signals. This paper proposes using frequency sweep keying modulation to provide robustness against overlap and a faster region-based convolutional neural network (R-CNN) demodulator to reduce the interference caused by heterogeneous signals. The demodulator works by training Faster R-CNN with the spectrograms of various received signals and classifying the received signals using Faster R-CNN. Experiments implementing an ultrasonic crosstalk environment showed that, compared to on-off keying (OOK), phase-shift keying (PSK), and frequency-shift keying (FSK), the proposed method can implement CDMA even with shorter codes and is robust against overlap. Compared to correlation-based frequency sweep keying, the time-of-flight error was reduced by approximately 75%. While the existing demodulators did not consider heterogeneous signals, the proposed method ignored approximately 99% of the OOK and PSK signals and approximately 79% of the FSK signals. The proposed method performed better than the existing methods and is expected to be used in various applications.
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The increased peripheral arterial disease (PAD) incidence associated with aging and increased incidence of cardiovascular conditions underscores the significance of assessing lower limb perfusion. This study aims to report on the correlation and utility of two novel non-invasive instruments: transcutaneous oxygen pressure (TcPO2 ) and forward-looking infrared (FLIR) thermography. A total of 68 patients diagnosed with diabetic foot ulcer and PAD who underwent vascular studies at a single institution between March 2022 and March 2023 were included. Cases with revascularization indications were treated by a cardiologist. Following the procedure, ambient TcPO2 and FLIR thermography were recorded on postoperative days 1, 7, 14, 21 and 28. In impaired limbs, TcPO2 was 12.3 ± 2 mmHg and FLIR thermography was 28.7 ± 0.9°C. TcPO2 (p = 0.002), FLIR thermography (p = 0.015) and ankle-brachial index (p = 0.047) values significantly reduced with greater vascular obstruction severity. Revascularization (n = 39) significantly improved TcPO2 (12.5 ± 1.7 to 19.1 ± 2.2 mmHg, p = 0.011) and FLIR (28.8 ± 1.8 to 32.6 ± 1.6°C; p = 0.018), especially in severe impaired angiosomes. TcPO2 significantly increased immediately post-procedure, then gradually, whereas the FLIR thermography values plateaued from day 1 to 28 post-procedure. In conclusion, FLIR thermography is a viable non-invasive tool for evaluating lower limb perfusion based on angiosomes, comparable with TcPO2 .
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The C-terminal region of the tumor suppressor protein p53 contains three domains, nuclear localization signal (NLS), tetramerization domain (TET), and C-terminal regulatory domain (CTD), which are essential for p53 function. Characterization of the structure and interactions of these domains within full-length p53 has been limited by the overall size and flexibility of the p53 tetramer. Using trans-intein splicing, we have generated full-length p53 constructs in which the C-terminal region is isotopically labeled with 15N for NMR analysis, allowing us to obtain atomic-level information on the C-terminal domains in the context of the full-length protein. Resonances of NLS and CTD residues have narrow linewidths, showing that these regions are largely solvent-exposed and dynamically disordered, whereas resonances from the folded TET are broadened beyond detection. Two regions of the CTD, spanning residues 369-374 and 381-388 and with high lysine content, make dynamic and sequence-independent interactions with DNA in regions that flank the p53 recognition element. The population of DNA-bound states increases as the length of the flanking regions is extended up to approximately 20 base pairs on either side of the recognition element. Acetylation of K372, K373, and K382, using a construct of the transcriptional coactivator CBP containing the TAZ2 and acetyltransferase domains, inhibits interaction of the CTD with DNA. This work provides high-resolution insights into the behavior of the intrinsically disordered C-terminal regions of p53 within the full-length tetramer and the molecular basis by which the CTD mediates DNA binding and specificity.
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DNA , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/metabolismo , Estrutura Terciária de Proteína , Ligação Proteica , Marcação por Isótopo , DNA/químicaRESUMO
Various sensors are embedded in automobiles to implement intelligent safety technologies such as autonomous driving and front-rear collision avoidance technology. In particular, ultrasonic sensors have been used in the past because they have an accuracy of centimeters to sub-centimeters in air despite their low cost and low hardware complexity. Recently, the crosstalk problem between ultrasonic sensors has been raised because the number of ultrasonic sensors in the unit space has increased as the number of vehicles increases. Various studies have been conducted to solve the crosstalk, but a demodulation error occurs when signals overlap. Therefore, in this paper, we propose a method that is robust to ultrasonic signal overlap, is robust even at shorter code length, and has reduced time of flight (TOF) error compared to the existing method by applying frequency sweep keying modulation based on code division multiple access (CDMA). As a result of the experiment, the code was detected accurately regardless of the overlap ratio of the two signals, and it was robust even in situations where the power of the two signals was different. In addition, it shows an accurate TOF estimation even if the ID code length is shorter than the existing on-off-keying, frequency shift keying, and phase shift keying methods.
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BACKGROUND: Self-expanding nitinol stent (SENS) implantation is commonly oversized in the superficial femoral artery (SFA), and leads to chronic outward force (COF) and in-stent restenosis (ISR). This study aimed to investigate the impact of COF of oversizing SENS on ISR of SFA. METHODS: In patients with implanted SENS in SFA, intimal hyperplasia especially between proximal segment and distal segment was evaluated by quantitative angiography, and the impact of COF on mid-term angiographic outcomes was investigated. In addition, porcine model with implanted SENS was used to evaluate the impact of COF on angiographic and histopathologic outcomes at 1 month. Excised stented arteries were evaluated by histopathologic analysis. RESULTS: We analyzed 65 SENS in 61 patients with follow-up angiography at 6 months to 1 year. The baseline diameter was 6.8 ± 0.71 mm and length were 97.0 ± 33.8 mm for the SENS. The ratio of the diameter of the stent to the reference vessel was 1.3 ± 0.24 at the proximal portion and 1.53 ± 0.27 at the distal portion (P < 0.001). In the long SFA stent, stent-to-vessel ratio was significantly higher in the distal stent than in the proximal stent (1.3 ± 0.2 vs. 1.55 ± 0.25, P = 0.001). ISR incidence was higher at the distal stent (37.3% vs 52.6%, P = 0.029). All 11 pigs survived for 4 weeks after SENS implantation. The vessel diameter was 4.04 ± 0.40 mm (control group) vs 4.45 ± 0.63 mm (oversized group), and the implanted stent diameter was 5.27 ± 0.46 mm vs. 7.18 ± 0.4 mm (P = 0.001). The stent-to-vessel diameter ratio was 1.31 ± 0.12 versus 1.63 ± 0.20 (P < 0.001). After 4 weeks, restenosis % was 29.5 ± 12.9% versus 46.8 ± 21.5% (P = 0.016). The neointimal area was 5.37 ± 1.15 mm2 vs. 8.53 ± 5.18 mm2 (P = 0.05). The restenosis % was 39.34 ± 8.53% versus 63.97 ± 17.1% (P = 0.001). CONCLUSIONS: COF is an important cause of restenosis in the distal portion of the SFA stent. Optimal sizing of the SFA stent is important to reduce the incidence of restenosis. Therefore, COF was an important factor of restenosis following distal SFA stenting.
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Angioplastia/instrumentação , Artéria Femoral/fisiopatologia , Hemodinâmica , Doença Arterial Periférica/terapia , Stents Metálicos Autoexpansíveis , Ligas , Angioplastia/efeitos adversos , Animais , Constrição Patológica , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Humanos , Modelos Animais , Neointima , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Doença Arterial Periférica/fisiopatologia , Desenho de Prótese , Falha de Prótese , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Estresse Mecânico , Sus scrofa , Fatores de Tempo , Resultado do TratamentoRESUMO
AIM: This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and a prospective observational study. METHOD: In vitro experiments were performed to evaluate the correlation between conditional factors such as camera distance, surrounding lighting, fluorescence emission sources and ICG doses. The fluorescence intensity was measured from the ICG-containing test tube in each condition. In the clinical study, ICG angiography was applied to patients with colorectal cancer (n = 164). The quantitative perfusion parameters were the maximal fluorescence intensity (FMAX ), slope, T1/2MAX and perfusion time ratio (TR). Camera position, distance to colon, fluorescence emission source, surrounding lighting, site of angiography and ICG specific mode were considered as conditional factors and compared with the quantitative parameters to identify the optimal condition of ICG angiography. RESULTS: The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at a distance of 4-5 cm by slope differential. FMAX , T1/2MAX and slope were affected significantly by camera distance, site of angiography, fluorescence emission source and ICG mode as conditional factors. On multivariate analysis, FMAX was independently associated with spectral ICG mode with red inversion, laser mode and camera distance. Conversely, TR was not related to any conditional factors. CONCLUSION: Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.
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Neoplasias Colorretais , Cirurgia Colorretal , Laparoscopia , Fístula Anastomótica , Angiografia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/cirurgia , Angiofluoresceinografia , Humanos , Verde de Indocianina , PerfusãoRESUMO
BACKGROUND: The comparative clinical outcomes between prediabetes and type 2 diabetes mellitus (T2DM) in older adults with AMI in the era of newer-generation drug-eluting stents (DES) are limited. We investigated the 2-year clinical outcomes of these patients. METHODS: A total of 5492 AMI patients aged ≥65 years were classified into three groups according to their glycemic status: normoglycemia (group A: 1193), prediabetes (group B: 1696), and T2DM (group C: 2603). The primary outcome was the occurrence of major adverse cardiac events (MACE), defined as all-cause death, recurrent myocardial infarction (Re-MI), and any repeat revascularization. The secondary outcome was stent thrombosis (ST). RESULTS: The primary and secondary outcomes cumulative incidences were similar between the prediabetes and T2DM groups. In both the prediabetes and T2DM groups, the cumulative incidences of MACE (adjusted hazard ratio [aHR]: 1.373; p = 0.020 and aHR: 1.479; p = 0.002, respectively) and all-cause death or MI (aHR: 1.436; p = 0.022 and aHR: 1.647; p = 0.001, respectively) were significantly higher than those in the normoglycemia group. Additionally, the cumulative incidence of all-cause death in the T2DM group was significantly higher than that in the normoglycemia group (aHR, 1.666; p = 0.003). CONCLUSIONS: In this retrospective study, despite the 2-year clinical outcomes of the patients with prediabetes and T2DM in the older adults were worse than those in the normoglycemia group; they were similar between the prediabetes and T2DM groups. Hence, comparable treatment strategies should be strengthened between prediabetes and T2DM in older adults with AMI. TRIAL REGISTRATION: Retrospectively registered.
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Diabetes Mellitus Tipo 2 , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Estado Pré-Diabético , Idoso , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The histone acetyl transferases CREB-binding protein (CBP) and its paralog p300 play a critical role in numerous cellular processes. Dysregulation of their catalytic activity is associated with several human diseases. Previous work has elucidated the regulatory mechanisms of p300 acetyltransferase activity, but it is not known whether CBP activity is controlled similarly. Here, we present the crystal structure of the CBP catalytic core encompassing the bromodomain (BRD), CH2 (comprising PHD and RING), HAT, and ZZ domains at 2.4-Å resolution. The BRD, PHD, and HAT domains form an integral structural unit to which the RING and ZZ domains are flexibly attached. The structure of the apo-CBP HAT domain is similar to that of acyl-CoA-bound p300 HAT complexes and shows that the acetyl-CoA binding site is stably formed in the absence of cofactor. The BRD, PHD, and ZZ domains interact with small ubiquitin-like modifier 1 (SUMO-1) and Ubc9, and function as an intramolecular E3 ligase for SUMOylation of the cell cycle regulatory domain 1 (CRD1) of CBP, which is located adjacent to the BRD. In vitro HAT assays suggest that the RING domain, the autoregulatory loop (AL) within the HAT domain, and the ZZ domain do not directly influence catalytic activity, whereas the BRD is essential for histone H3 acetylation in nucleosomal substrates. Several lysine residues in the intrinsically disordered AL are autoacetylated by the HAT domain. Upon autoacetylation, acetyl-K1596 (Ac-K1596) binds intramolecularly to the BRD, competing with histones for binding to the BRD and acting as a negative regulator that inhibits histone H3 acetylation.
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Proteína de Ligação a CREB/química , Histonas/química , Sumoilação , Acetilação , Acetiltransferases/metabolismo , Animais , Sítios de Ligação , Domínio Catalítico , Escherichia coli/metabolismo , Células HeLa , Histona Acetiltransferases/metabolismo , Humanos , Camundongos , Proteína SUMO-1/química , Transcrição Gênica , Enzimas de Conjugação de Ubiquitina/químicaRESUMO
BACKGROUND: The clinical benefits and outcomes of the interventional treatment of small-sized infrapopliteal arteries using stent implantation remain uncertain. The aim of this study was to compare the safety and efficacy of drug-free bioresorbable vascular scaffold (BVS) with that of bare metal stent (BMS) in endovascular treatment of small-sized peripheral arteries. METHODS: In this study, drug-free BVS and BMS were used in eight porcine models. We compared the angiographic and histomorphometric findings in the two groups at 4 weeks. In each pig, BVS and BMS of adequate sizes were implanted in the small branch (<3 mm) of the femoral artery. Angiography, intravascular ultrasound (IVUS), and histomorphometric analysis were performed at 4 weeks. RESULTS: In the 4-week follow-up angiography and IVUS examination, the minimal luminal diameter was smaller and diameter stenosis was more severe in the BVS group. Histomorphometric findings indicated that the lumen area in the BVS group was smaller (0.34 ± 0.28 mm2 vs. 1.40 ± 0.52 mm2, P < 0.001), whereas the neointimal area (2.70 ± 1.28 mm2 vs. 1.76 ± 0.66 mm2, P = 0.013), area stenosis (85.18 ± 13.14 % vs. 54.99 ± 16.13 %, P < 0.001), inflammatory score (2.07 ± 0.861 vs. 28 ± 0.39, P = 0.003), and fibrin scores (1.24 ± 0.70 vs. 0.79 ± 0.72, P = 0.043) were significantly higher in the BVS group. The injury score was higher in the BMS group. In histopathologic findings, restenosis was mainly due to recoil and distortion of the scaffold in the BVS group. CONCLUSIONS: Compared with BMS, drug-free BVS was not feasible for small-sized peripheral arteries based on the angiographic, IVUS, and histomorphometric results primarily due to insufficient mechanical support.
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Implantes Absorvíveis , Angioplastia com Balão/instrumentação , Stents Farmacológicos , Artéria Femoral , Metais , Stents , Angiografia , Angioplastia com Balão/efeitos adversos , Animais , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Masculino , Desenho de Prótese , Sus scrofa , Fatores de Tempo , Ultrassonografia de Intervenção , Grau de Desobstrução VascularRESUMO
Plasmodesmata (PD), unique to the plant kingdom, are structurally complex microchannels that cross the cell wall to establish symplastic communication between neighbouring cells. Viral intercellular movement occurs through PD. To better understand the involvement of PD in viral infection, we conducted a quantitative proteomic study on the PD-enriched fraction from Nicotiana benthamiana leaves in response to infection by Turnip mosaic virus (TuMV). We report the identification of a total of 1070 PD protein candidates, of which 100 (≥2-fold increase) and 48 (≥2-fold reduction) are significantly differentially accumulated in the PD-enriched fraction, when compared with protein levels in the corresponding healthy control. Among the differentially accumulated PD protein candidates, we show that an α-expansin designated NbEXPA1, a cell wall loosening protein, is PD-specific. TuMV infection downregulates NbEXPA1 mRNA expression and protein accumulation. We further demonstrate that NbEXPA1 is recruited to the viral replication complex via the interaction with NIb, the only RNA-dependent RNA polymerase of TuMV. Silencing of NbEXPA1 inhibits plant growth and TuMV infection, whereas overexpression of NbEXPA1 promotes viral replication and intercellular movement. These data suggest that NbEXPA1 is a host factor for potyviral infection. This study not only generates a PD-proteome dataset that is useful in future studies to expound PD biology and PD-mediated virus-host interactions but also characterizes NbEXPA1 as the first PD-specific cell wall loosening protein and its essential role in potyviral infection.
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Nicotiana/microbiologia , Doenças das Plantas/virologia , Proteínas de Plantas/metabolismo , Plasmodesmos/metabolismo , Potyvirus/metabolismo , Potyvirus/fisiologia , Proteômica , Nicotiana/metabolismo , Replicação ViralRESUMO
The human muscleblind-like proteins (MBNL) regulate tissue-specific splicing by targeting cardiac troponin T and other pre-mRNAs; aberrant targeting of CUG and CCUG repeat expansions frequently accompanies the neuromuscular disease myotonic dystrophy. We show, using biolayer interferometry (Octet) and NMR spectroscopy, that the zinc finger domains of MBNL isoform 1 (MBNL1) are necessary and sufficient for binding CGCU sequences within the pre-mRNA of human cardiac troponin T. Protein constructs containing zinc fingers 1 and 2 (zf12) and zinc fingers 3 and 4 (zf34) of MBNL1 each fold into a compact globular tandem zinc finger structure that participates in RNA binding. NMR spectra show that the stoichiometry of the interaction between zf12 or zf34 and the CGCU sequence is 1:1, and that the RNA is single-stranded in the complex. The individual zinc fingers within zf12 or zf34 are nonequivalent: the primary RNA binding surface is formed in each pair by the second zinc finger (zf2 or zf4), which interacts with the CGCU RNA sequence. The NMR structure of the complex between zf12 and a 15-base RNA of sequence 95GUCUCGCUUUUCCCC109, containing a single CGCU element, shows the single-stranded RNA wrapped around zf2 and extending to bind to the C-terminal helix. Bases C101, U102, and U103 make well-defined and highly ordered contacts with the protein, whereas neighboring bases are less well-ordered in the complex. Binding of the MBNL zinc fingers to cardiac troponin T pre-mRNA is specific and relatively simple, unlike the complex multiple dimer-trimer stoichiometries postulated in some previous studies.
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Motivos de Nucleotídeos , RNA Mensageiro/química , Proteínas de Ligação a RNA/química , Troponina T , Humanos , Ligação Proteica , Domínios Proteicos , Splicing de RNA/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Dedos de ZincoRESUMO
In the fasted state, increases in catecholamine signaling promote adipocyte function via the protein kinase A-mediated phosphorylation of cyclic AMP response element binding protein (CREB). CREB activity is further up-regulated in obesity, despite reductions in catecholamine signaling, where it contributes to the development of insulin resistance. Here we show that obesity promotes the CREB binding protein (CBP)-mediated acetylation of CREB at Lys136 in adipose. Under lean conditions, CREB acetylation was low due to an association with the energy-sensing NAD(+)-dependent deacetylase SirT1; amounts of acetylated CREB were increased in obesity, when SirT1 undergoes proteolytic degradation. Whereas CREB phosphorylation stimulated an association with the KIX domain of CBP, Lys136 acetylation triggered an interaction with the CBP bromodomain (BRD) that augmented recruitment of this coactivator to the promoter. Indeed, coincident Ser133 phosphorylation and Lys136 acetylation of CREB stimulated the formation of a ternary complex with the KIX and BRD domains of CBP by NMR analysis. As disruption of the CREB:BRD complex with a CBP-specific BRD inhibitor blocked effects of CREB acetylation on target gene expression, our results demonstrate how changes in nutrient status modulate cellular gene expression in response to hormonal signals.
Assuntos
Adipócitos/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Obesidade/metabolismo , Transdução de Sinais , Células 3T3-L1 , Acetilação , Animais , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Immunoblotting , Lisina/genética , Lisina/metabolismo , Camundongos , Camundongos Knockout , Camundongos Obesos , Mutação , Obesidade/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Regiões Promotoras Genéticas/genética , Ligação Proteica , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
This laboratory study evaluated the effect of glare source (halogen, HID and LED) and its illumination levels (0.7, 2 and 5 lx) using a quantitative methodology. Pupil diameter and electroencephalography were measured using FaceLab and Biopac systems, respectively. The discomfort glare was assessed subjectively with Borg's CR-10 scale. Twenty healthy subjects participated. Pupil size was significantly affected by the headlamp type and illumination condition. Pupil size was smaller when exposed to the LED headlamp than other headlamps (Halogen > HID > LED). In addition, when the illumination increased, pupil size decreased (0.7 lx > 2 lx > 5 lx). Also, driver's discomfort increased when pupil size was small, and theta waves were high. This discomfort may cause reduced attention and safety of the driver. These results can be applied to design and development of headlamps. Further investigation is necessary with adopted methodology to evaluate other headlamps in different illumination conditions. Practitioner Summary: This study evaluated pupil size and electroencephalography under different glare source (halogen, HID and LED) and illumination levels (0.7, 2 and 5 lx). Driver's discomfort increased when pupil size was small, and theta waves were high. This discomfort may cause reduced attention and safety of the driver.
Assuntos
Condução de Veículo , Ofuscação , Luz , Iluminação , Pupila/fisiologia , Adulto , Automóveis , Eletroencefalografia , Humanos , Masculino , Reflexo PupilarRESUMO
Interactions between proteins and carbohydrates are ubiquitous in biology. Therefore, understanding the factors that determine their affinity and selectivity are correspondingly important. Herein, we have determined the relative strengths of intramolecular interactions between a series of monosaccharides and an aromatic ring close to the glycosylation site in an N-glycoprotein host. We employed the enhanced aromatic sequon, a structural motif found in the reverse turns of some N-glycoproteins, to facilitate face-to-face monosaccharide-aromatic interactions. A protein host was used because the dependence of the folding energetics on the identity of the monosaccharide can be accurately measured to assess the strength of the carbohydrate-aromatic interaction. Our data demonstrate that the carbohydrate-aromatic interaction strengths are moderately affected by changes in the stereochemistry and identity of the substituents on the pyranose rings of the sugars. Galactose seems to make the weakest and allose the strongest sugar-aromatic interactions, with glucose, N-acetylglucosamine (GlcNAc) and mannose in between. The NMR solution structures of several of the monosaccharide-containing N-glycoproteins were solved to further understand the origins of the similarities and differences between the monosaccharide-aromatic interaction energies. Peracetylation of the monosaccharides substantially increases the strength of the sugar-aromatic interaction in the context of our N-glycoprotein host. Finally, we discuss our results in light of recent literature regarding the contribution of electrostatics to CH-π interactions and speculate on what our observations imply about the absolute conservation of GlcNAc as the monosaccharide through which N-linked glycans are attached to glycoproteins in eukaryotes.