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This case report features a 62-year-old male with stage IB lung adenocarcinoma harboring an epidermal growth factor receptor exon 19 deletion, who underwent treatment with osimertinib following a left upper lobectomy and lymph node dissection. Despite a history of smoking and well-managed type 2 diabetes, the patient developed heart failure 18 months post-initiation of osimertinib therapy, marking one of the latest occurrences of heart failure following osimertinib treatment documented in limited literature. Cardiac MRI revealed significant left ventricular enlargement, lateral wall myocardial thinning, and localized myocardial fibrosis without perfusion defects, a finding not previously reported in literature. This case underscores the severe and unusual cardiac effects of osimertinib in patients with latent risk factors, highlighting the importance of vigilant cardiac monitoring and a multidisciplinary management approach.
Assuntos
Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Cardiotoxicidade , Neoplasias Pulmonares , Humanos , Acrilamidas/efeitos adversos , Acrilamidas/uso terapêutico , Compostos de Anilina/efeitos adversos , Compostos de Anilina/uso terapêutico , Masculino , Neoplasias Pulmonares/tratamento farmacológico , Pessoa de Meia-Idade , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cardiotoxicidade/etiologia , Antineoplásicos/efeitos adversos , Insuficiência Cardíaca/induzido quimicamente , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Indóis , PirimidinasRESUMO
A 25-year-old male with tachycardia and right heart enlargement was diagnosed with atrial-ventricular nodal reentrant tachycardia (AVNRT) and successfully treated with radiofrequency ablation. Cardiac MRI confirmed right heart enlargement but ruled out cardiomyopathy. Further imaging revealed a rare congenital absence of the portal vein (CAPV) with an associated portosystemic shunt. This case highlights the importance of considering CAPV in unexplained cardiac symptoms and structural heart changes.
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Recently, a few AB-type multiblock copolymers have been successfully designed to form stable square cylinder phase based on self-consistent field theory (SCFT) calculations. The previous works only identify the stability region of the square phase but not analyzing its stability, which is closely related to the free-energy landscape. In this work, we have reexamined the stability of the square phase in B 1 A 1 B 2 A 2 B 3 ${{{\rm B}}_{1}{{\rm A}}_{1}{{\rm B}}_{2}{{\rm A}}_{2}{{\rm B}}_{3}}$ linear pentablock and ( B 1 A B 2 )â 5 ${({{\rm B}}_{1}{\rm A}{{\rm B}}_{2}{)}_{5}}$ star triblock copolymers by drawing the free-energy landscape with respect to the two dimensions of a rectangular unit cell. Our results demonstrate that the square phase continuously transfers to the rectangular phase as the degree of packing frustration is gradually released. Moreover, the prolate contour lines of the free-energy landscape indicate the weak stability of the square phase in the B 1 A 1 B 2 A 2 B 3 ${{{\rm B}}_{1}{{\rm A}}_{1}{{\rm B}}_{2}{{\rm A}}_{2}{{\rm B}}_{3}}$ copolymer. In contrast, the stability of the square phase is notably improved in the ( B 1 A B 2 )â 5 ${({{\rm B}}_{1}{\rm A}{{\rm B}}_{2}{)}_{5}}$ copolymer due to its enhanced concentration of bridging configurations. Our work sheds light on the understanding of the stability of the square cylinder phase in block copolymers. Accordingly, we propose some possible strategies for further designing new AB-type block copolymer systems to obtain more stable square phase.
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Chiral nanostructures of nanoparticle assemblies have attracted tremendous interest for their fascinating functional properties. Herein, through theoretical simulations, it is shown that nanoparticle tethered block copolymers can self-assemble into hierarchically chiral nanostructures. Twofold helices are formed in the hierarchically chiral nanostructures: the diblock copolymers form helical supercylinders while the nanoparticles arrange into chiral assemblies wrapped around the helical supercylinders. The hierarchically chiral nanostructures can be formed in a large parameter window. Circular dichroism calculations demonstrate that the coexistence of polymeric helices and chiral nanoparticle assemblies improves the chiroptical activity. These findings can provide guidelines for designing hierarchically ordered chiral nanostructures with advanced functional properties.
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Nanopartículas , Nanoestruturas , Dicroísmo Circular , Nanoestruturas/química , PolímerosRESUMO
Cardiac amyloidosis presented with normal interventricular septum is an extremely rare entity, and diagnosis may be difficult. This report discusses a 44-year-old female who presented with worsening dyspnoea on exertion, orthopnoea, and lower-extremity oedema. Electrocardiogram depicted low voltage in limb leads and a pseudoinfarct pattern. Echocardiogram revealed biatrial dilatation without changes of ventricular chambers and restrictive filling physiology. A diagnosis of cardiac amyloidosis was considered. Cardiac MRI was pursued, showing delayed gadolinium enhancement, and this ultimately led to the myocardial biopsy confirming the diagnosis of cardiac amyloidosis. The case suggests that patients who present with heart failure of uncertain aetiology, amyloidosis could be a cause of cardiomyopathy despite the absence of "classical" echocardiographic features of amyloid deposition such as an increased interventricular septum thickness or"brilliant sparkled"appearance of the myocardium.
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Amiloidose , Cardiomiopatias , Septo Interventricular , Feminino , Humanos , Adulto , Meios de Contraste , Gadolínio , Amiloidose/diagnóstico , Amiloidose/patologia , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Septo Interventricular/diagnóstico por imagem , Miocárdio/patologiaRESUMO
Directing nanoparticles into ordered organization in polymer matrix to improve macroscopic properties of nanocomposites remains a challenge. Herein, by means of theoretical simulations, we show the high permittivity of hybrid nanostructures designed with mixtures of AB block copolymer-grafted nanoparticles and lamella-forming AC diblock copolymers. The grafted nanoparticles self-assemble into parallel stripes or highly ordered networks in the lamellae of the AC diblock copolymers. The ordered nanoparticle networks, including honeycomb-like and kagomé networks, provide bending and conductive pathways for concentrating electric fields, which results in the improvement of the permittivity. We envisage that this strategy will open a gateway to prepare hierarchically ordered functional nanocomposites with distinctive dielectric properties.
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Hybrid materials with hierarchical nanostructures are of great interest for their advanced functions. However, the effect of the formation of hierarchical nanostructures on properties is not well understood. Here, through combining dissipative particle dynamics simulation and the finite-difference time-domain method, the optical properties of hierarchically ordered nanostructures formed by mixtures of A(BC)n multiblock copolymers and nanoparticles (NPs) are investigated. A series of hierarchically ordered nanostructures with multiple small-length-scale hybrid domains are obtained from the self-assembly of A(BC)n /NP. An increase and blueshift in optical absorption are observed when the number of small-length-scale hybrid domains increases. The small-length-scale hybrid domains enhance light scattering, which consequently contributes to the improved optical performance. These findings can yield guidelines for designing hierarchically ordered functional nanocomposites with light-harvesting characteristics.
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Nanoestruturas/química , Polímeros/química , Simulação de Dinâmica Molecular , Fenômenos Ópticos , Polímeros/síntese químicaRESUMO
Chiral nanoarchitectures usually possess unique and intriguing properties. However, the construction of 2D chiral nanopatterns through polymer self-assembly is a challenge. Reported herein is the formation of chiral stripe nanopatterns through surface self-assembly of polypeptide-based rod-coil block copolymers on microstripes. The nanostripes align oblique to the boundary of the microstripes, resulting in the chirality of the nanopatterns. The chirality of the nanopatterns is closely related to the width of the microstripes, i.e., a narrower width results in higher chirality. Besides, the chiral sense of the nanopatterns can be regulated by the chirality of the polypeptide blocks. This work demonstrates the transmission of chirality from polymer to nanoarchitecture on a confined surface, which can guide the preparation of nanopatterns with tuned chiral features.
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Micelas , Polímeros , PeptídeosRESUMO
A 36-year-old woman, who had a history of myomectomy, presented with lightheadedness after changing position from sitting to standing and effort-related shortness of breath. Echocardiography demonstrated a hyperechoic elongated mobile mass extending from the inferior caval vein to the right atrium. The mass was surgically removed, and histological examination established the diagnosis of intravenous leiomyomatosis. This case caught the attention of our cardiology group to consider the diagnosis when an inferior caval vein or right atrium mass is found in a patient with a history of uterine leiomyomatosis.
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Átrios do Coração/fisiopatologia , Insuficiência Cardíaca/etiologia , Hipotensão Ortostática/etiologia , Leiomiomatose/complicações , Leiomiomatose/diagnóstico por imagem , Neoplasias Vasculares/diagnóstico por imagem , Adulto , Ecocardiografia , Feminino , Humanos , Leiomiomatose/cirurgia , Tomografia Computadorizada por Raios X , Neoplasias Vasculares/cirurgia , Veia Cava InferiorRESUMO
OBJECTIVES: The present study tested the hypothesis that pretreatment with metformin decreases postprocedural myocardial injury and improves clinical outcomes in metabolic syndrome patients following percutaneous coronary intervention (PCI). METHODS: We enrolled 152 metabolic syndrome patients with no prior history of metformin treatment. Patients scheduled for elective coronary intervention were randomized to the metformin or control group 7 days before the procedure. Creatine kinase-MB (CK-MB) and troponin I levels were measured at baseline and 8 and 24 h after the procedure, and clinical outcomes were monitored for 1 year. RESULTS: Post-PCI myocardial injury as indicated by CK-MB elevation (14.5 vs. 32.9%, p = 0.008) and troponin I elevation (14.5 vs. 34.2%, p = 0.005) was significantly lower in the metformin group than in the control group. Postprocedural peak values of CK-MB (2.70 ± 4.30 vs. 6.29 ± 8.03 ng/ml, p < 0.001) and troponin I (0.02 ± 0.05 vs. 0.07 ± 0.10 ng/ml, p = 0.001) were also significantly lower in the metformin group than in the control group. At 1 year, the composite endpoint of death from any cause, post-PCI myocardial infarction (MI), MI after PCI hospitalization or ischemia-driven target lesion revascularization occurred in 7.9% of metformin-treated patients and 28.9% of controls (hazard ratio 0.25, 95% CI 0.10-0.62, log rank p = 0.001). CONCLUSIONS: A 7-day metformin pretreatment regimen (250 mg 3 times a day) significantly reduces postprocedural myocardial injury and improves 1-year clinical outcomes in metabolic syndrome patients undergoing PCI.
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Cardiotônicos/uso terapêutico , Síndrome Metabólica/complicações , Metformina/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Adulto , Idoso , Biomarcadores/metabolismo , Creatina Quinase Forma MB/metabolismo , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Troponina I/metabolismo , Adulto JovemRESUMO
This imaging observation underscores a rare single coronary artery anomaly, wherein the right coronary artery originates from the left anterior descending artery (LAD). The stenosis in the proximal LAD adds complexity, emphasizing the need for multidisciplinary evaluation and decision-making.
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Doença da Artéria Coronariana , Anomalias dos Vasos Coronários , Humanos , Constrição Patológica , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico por imagemRESUMO
It has been commonly believed that the ordered thermoplastic elastomers formed by the ABC triblock copolymer should have better mechanical performance than that by the ABA counterpart due to the higher bridging fraction. However, the thermoplastic elastomer of ABA was often observed to perform better than that of ABC. To compare the performance of two kinds of thermoplastic elastomers and unveil the underlying microscopic mechanism, we have calculated their stress-strain curves using coarse-grained molecular dynamics simulations in conjunction with self-consistent field theory. It is revealed that the stretching degree of the bridging blocks and the network connectivity play important roles in determining the mechanical properties in addition to the bridging fraction. The higher degree in the stretching of bridging blocks and network connectivity of the structure formed by the ABA triblock copolymer enables its superior mechanical performance over the ABC block copolymer.
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Block copolymers with different architectures can possibly generate innumerable stable or metastable structures and thus provide an irreplaceable platform for theoretically exploring novel structures. Self-consistent field theory (SCFT) is a powerful tool to predict the ordered structures of block copolymers; however, it is sensitively dependent on its initial condition. Here we propose to use multiple symmetry-adapted basis functions to generate the initial conditions of SCFT and then apply Bayesian optimization to search for ordered structures by navigating the coefficient space of these basis functions. Without any prior knowledge, our scheme can automatically recover hundreds of ordered structures for two simple block copolymers, including most of the common structures and complex Frank-Kasper structures, together with many novel structures. By applying the automated scheme to various block copolymers, a huge number of novel structures can be obtained to expand the structural library, which may create new opportunities for the scientific community.
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Spirals are common in nature; however, they are rarely observed in polymer self-assembly systems, and the formation mechanism is not well understood. Herein, we report the formation of two-dimensional (2D) spiral patterns via microdisk substrate-mediated solution self-assembly of polypeptide-based rod-coil block copolymers. The spiral pattern consists of multiple strands assembled from the block copolymers, and two central points are observed. The spirals fit well with the Archimedean spiral model, and their chirality is dependent on the chirality of the polypeptide blocks. As revealed by a combination of experiments and theoretical simulations, these spirals are induced by an interplay of the parallel ordering tendency of the strands and circular confinement of the microdisks. This work presents the first example regarding substrate-mediated self-assembly of block copolymers into spirals. The gained information could not only enhance our understanding of natural spirals but also assist in both the controllable preparations and applications of spiral nanostructures.
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It is a challenging task to realize the periodically bicontinuous gyroid nanostructures of flexible nanocomposites with high loading of functionalized nanoparticles, which could exhibit high dielectric permittivity for energy storage and electronic devices. Herein, with the aid of the concept of macromolecular engineering, we propose novel nanocomposites, composed of A'(A''B)n miktoarm star copolymers and nanoparticles, to obtain a double-gyroid structure through self-consistent field theory coupled with density functional theory. By tailoring the architecture of this copolymer, a large window of the double-gyroid phase extending to a high loading concentration of nanoparticles is achieved, leading to a hierarchical structure of a percolation network of nanoparticles within the gyroid channels. Furthermore, the finite difference quasielectrostatic method is integrated to reveal an enhanced dielectric permittivity of the structured nanocomposites by increasing the loading concentration of nanoparticles. The simultaneous achievement of an ordered double-gyroid phase and high loading nanoparticles represents a crucial step toward the realization of fully three-dimensional network-like metamaterials via a rational molecular design of nanocomposites.
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Spiral nanostructures, mainly in the 2D form, have been observed in polymer self-assembly, while well-defined 3D spirals are rarely reported. Here we report that a binary system containing polypeptide-based block copolymers and homopolymers can self-assemble into well-defined spiral spheres (3D spirals), in which the homopolymers form the core and the copolymers form the spirals. Upon increasing the preparation temperature, meridian spheres were obtained. Mixing polypeptide block copolymers with opposite backbone chirality also leads to the formation of meridian spheres. In the meridian patterns, a tighter packing manner of the phenyl groups appended to the polypeptide blocks was observed, which is responsible for the spiral-to-meridian transitions. This work enriches the research of spiral assemblies and provides a facile route to switch chiral/achiral nanostructures by regulating the packing manner of the pendant groups.
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Janus nanoparticles (JPs), which are anisotropic nanoparticles with multiple constituting parts, have been recognized as superior compatibilizers for polymer-blend-based nanocomposites. However, so far, most studies focused on the effects of symmetric JPs on the phase separation dynamics of polymer blends, while the roles of asymmetric JPs during phase separation remain unclear. In this work, the phase separation dynamics of symmetric blends compatibilized by JPs with various compositions was studied by using dissipative particle dynamics (DPD) simulations. It was found that the blends compatibilized by asymmetric JPs tend to undergo morphological transitions from bicontinuous networks to droplets-in-matrix structures at the late stage of phase separation, which is due to the influence of asymmetric JPs on the energetically favored curvature of the interfaces between polymer domains. Such a mechanism is absent for symmetric JPs and other compatibilizers (e.g., triblock copolymers and homogeneous particles) because they lack the unique combination of chemical asymmetry with the particulate nature like the asymmetric JPs. Moreover, it was observed that the asymmetric JPs can stably localize at the interfaces and act as efficient compatibilizers only when the fraction of the minor constituent part exceeds a critical value. These findings not only shed light upon the roles of asymmetric JPs as compatibilizers but also indicate a promising strategy for designing polymer-blend-based nanocomposites with tailor-made structures.
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Branched nanostructures with tunable arm numbers were prepared through the assembly of silica rods mediated by coalescence of catalyst droplets on the end of the rods. The formed primary branched colloids retain living characteristics similar to the original ones, that is, they can further assemble into multilevel and hierarchical branched structures.