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1.
Oncologist ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940449

RESUMO

BACKGROUND: Given the typical trajectory of glioblastoma, many patients lose decision-making capacity over time, which can lead to inadequate advance care planning (ACP) and end-of-life (EOL) care. We aimed to evaluate patients' current ACP and EOL care status. PATIENTS AND METHODS: We conducted a cohort study on 205 patients referred to oncologists at a Korean tertiary hospital between 2017 and 2022. We collected information on sociodemographic factors, cancer treatment, palliative care consultation, ACP, legal documents on life-sustaining treatment (LST) decisions, and aggressiveness of EOL care. RESULTS: With a median follow-up time of 18.3 months: 159 patients died; median overall survival: 20.3 months. Of the 159 patients, 11 (6.9%) and 63 (39.6%) had advance directive (AD) and LST plans, respectively, whereas 85 (53.5%) had neither. Among the 63 with LST plans, 10 (15.9%) and 53 (84.1%) completed their forms through self-determination and family determination, respectively. Of the 159 patients who died, 102 (64.2%) received palliative care consultation (median time: 44 days from the first consultation to death) and 78 (49.1%) received aggressive EOL care. Those receiving palliative care consultations were less likely to receive aggressive EOL care (83.3% vs 32.4%, P < .001), and more likely to use more than 3 days of hospice care at EOL (19.6% vs 68.0%, P < .001). CONCLUSIONS: The right to self-determination remains poorly protected among patients with glioblastoma, with nearly 90% not self-completing AD or LST plan. As palliative care consultation is associated with less aggressive EOL care and longer use of hospice care, physicians should promptly introduce patients to ACP conversations and palliative care consultations.

2.
J Korean Med Sci ; 39(22): e175, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859738

RESUMO

BACKGROUND: Multiple myeloma (MM) patients are at risk of skeletal-related events (SREs) like spinal cord compression, pathologic fractures, bone surgery, and radiation to bone. Real-world data regarding SREs in MM are limited. METHODS: We conducted a large, retrospective, nationwide cohort study using the Korean Health Insurance Review and Assessment Service (HIRA) database from 2007 to 2018. RESULTS: Over a 12-year study period, we identified 6,717 patients who developed symptomatic MM. After a median follow-up of 35.1 months (interquartile range [IQR], 20.8-58.2 months), 43.6% of these patients experienced SREs, and 39.6% had four or more SREs. One in five patients (20.0%) experienced pathologic fractures within the first year of follow-up. The median time to first SRE was 9.6 months (IQR, 1.2-25.8 months), with 3.0 months in the group with prior SREs and 19.8 months in the group without prior SREs. During follow-up, 78.5% of patients received bisphosphonates. Multiple logistic regression analysis revealed several factors associated with an increased risk of SREs, including being female (odds ratio [OR], 1.44), aged 50 or older (OR, 1.87), having cerebrovascular disease (OR, 1.34), undergoing first-line chemotherapy regimens not containing bortezomib or lenalidomide (OR, 1.49), and being in the group with prior SREs and bisphosphonate use (OR, 5.63), compared to the group without prior SREs and without bisphosphonate use. CONCLUSION: This population-based study is the first to report the incidence and risk factors of SREs in Korean MM patients, which can be used to assess their bone health.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/epidemiologia , Mieloma Múltiplo/patologia , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/complicações , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Difosfonatos/uso terapêutico , Fatores de Risco , Bases de Dados Factuais , República da Coreia/epidemiologia , Conservadores da Densidade Óssea/uso terapêutico , Razão de Chances , Fraturas Espontâneas/etiologia , Fraturas Espontâneas/epidemiologia , Compressão da Medula Espinal/etiologia , Adulto , Modelos Logísticos
3.
J Craniofac Surg ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012020

RESUMO

Apert's syndrome (AS) is a rare congenital malformation characterized by distinctive clinical manifestations such as syndactyly of the extremities and midface retrusion, which set it apart from other syndromes. This condition often presents with craniosynostosis and, less commonly, central nervous system abnormalities like encephalocele. In this report, we present a typical case of Apert syndrome with an occipital encephalocele. The infant had plagio-brachycephaly due to craniosynostosis and required urgent repair of the occipital encephalocele. At 1 month of age, we performed both the encephalocele repair and early cranioplasty for autologous bone grafting. This case underscores the importance of early diagnosis and surgical interventions in Apert's syndrome cases with encephalocele.

4.
Angew Chem Int Ed Engl ; 63(14): e202319395, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38353410

RESUMO

Porous polymer networks (PPNs) are promising candidates as photocatalysts for hydrogen production. Constructing a donor-acceptor structure is known to be an effective approach for improving photocatalytic activity. However, the process of how a functional group of a monomer can ensure photoexcited charges transfer and improve the hydrogen evolution rate (HER) has not yet been studied on the molecular level. Herein, we design and synthesize two kinds of triazatruxene (TAT)-based PPNs: TATR-PPN with a hexyl (R) group and TAT-PPN without the hexyl group, to understand the relationship between the presence of the functional group and charge transfer. The hexyl group on the TAT unit was found to ensure the transfer of photoexcited electrons from a donor unit to an acceptor unit and endowed the TATR-PPN with stable hydrogen production.

5.
Angew Chem Int Ed Engl ; 63(20): e202403017, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38429994

RESUMO

Crafting single-atom catalysts (SACs) that possess "just right" modulated electronic and geometric structures, granting accessible active sites for direct room-temperature benzene oxidation is a coveted objective. However, achieving this goal remains a formidable challenge. Here, we introduce an innovative in situ phosphorus-immitting strategy using a new phosphorus source (phosphorus nitride, P3N5) to construct the phosphorus-rich copper (Cu) SACs, designated as Cu/NPC. These catalysts feature locally protruding metal sites on a nitrogen (N)-phosphorus (P)-carbon (C) support (NPC). Rigorous analyses, including X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS), validate the coordinated bonding of nitrogen and phosphorus with atomically dispersed Cu sites on NPC. Crucially, systematic first-principles calculations, coupled with the climbing image nudged-elastic-band (CI-NEB) method, provide a comprehensive understanding of the structure-property-activity relationship of the distorted Cu-N2P2 centers in Cu/NPC for selective oxidation of benzene to phenol production. Interestingly, Cu/NPC has shown more energetically favorable C-H bond activation compared to the benchmark Cu/NC SACs in the direct oxidation of benzene, resulting in outstanding benzene conversion (50.3 %) and phenol selectivity (99.3 %) at room temperature. Furthermore, Cu/NPC achieves a remarkable turnover frequency of 263 h-1 and mass-specific activity of 35.2 mmol g-1 h-1, surpassing the state-of-the-art benzene-to-phenol conversion catalysts to date.

6.
Breast Cancer Res ; 25(1): 154, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38098054

RESUMO

BACKGROUND: The role of HER2 amplification level in predicting the effectiveness of HER2-directed therapies has been established. However, its association with survival outcomes in advanced HER2-positive breast cancer treated with dual HER2-blockade remains unexplored. METHODS: This is a single-center retrospective study of patients with advanced HER2-positive breast cancer treated with first-line pertuzumab, trastuzumab, and docetaxel. The primary objective was to ascertain the relationship between treatment outcomes and the level of HER2 amplification by in situ hybridization (ISH). RESULTS: A total of 152 patients were included with a median follow-up duration of 50.0 months. Among the 78 patients who received ISH, a higher HER2/CEP17 ratio correlated significantly with longer PFS (HR 0.50, p = 0.022) and OS (HR 0.28, p = 0.014) when dichotomized by the median. A higher HER2 copy number also correlated significantly with better PFS (HR 0.35, p < 0.001) and OS (HR 0.27, p = 0.009). In multivariate analysis, the HER2/CEP17 ratio was an independent predictive factor for PFS (HR 0.66, p = 0.004) and potentially for OS (HR 0.64, p = 0.054), along with HER2 copy number (PFS HR 0.85, p = 0.004; OS HR 0.84, p = 0.049). Furthermore, the correlation between HER2 amplification level by ISH with PFS and OS was consistent across the HER2 IHC 1+/2+ and 3+ categories. CONCLUSIONS: This is the first study to report that a higher level of HER2 amplification by ISH is associated with improved PFS and OS in advanced HER2-positive breast cancer treated with dual HER2-blockade. Notably, HER2 amplification level had a predictive role regardless of IHC results. Even in patients with HER2 protein expression of 3+, treatment outcome to HER2-directed therapy was dependent on the level of HER2 gene amplification.


Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Humanos , Feminino , Trastuzumab/uso terapêutico , Docetaxel , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Hibridização In Situ , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
7.
Angew Chem Int Ed Engl ; 62(36): e202307991, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37448236

RESUMO

Covalent organic frameworks (COFs) have emerged as a promising platform for photocatalysts. Their crystalline porous nature allows comprehensive mechanistic studies of photocatalysis, which have revealed that their general photophysical parameters, such as light absorption ability, electronic band structure, and charge separation efficiency, can be conveniently tailored by structural modifications. However, further understanding of the relationship between structure-property-activity is required from the viewpoint of charge-carrier transport, because the charge-carrier property is closely related to alleviation of the excitonic effect. In the present study, COFs composed of a fixed cobalt (Co) porphyrin (Por) centered tetraamine as an acceptor unit with differently conjugated di-carbaldehyde based donor units, such as benzodithiophene (BDT), thienothiophene (TT), or phenyl (TA), were synthesized to form Co-Por-BDT, Co-Por-TT, or Co-Por-TA, respectively. Their photocatalytic activity for reducing carbon dioxide into carbon monoxide was in the order of Co-Por-BDT>Co-Por-TT>Co-Por-TA. The results indicated that the excitonic effect, associated with their charge-carrier densities and π-conjugation lengths, was a significant factor in photocatalysis performance.

8.
Angew Chem Int Ed Engl ; 62(37): e202307459, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37488979

RESUMO

Despite the enormous interest in Li metal as an ideal anode material, the uncontrollable Li dendrite growth and unstable solid electrolyte interphase have plagued its practical application. These limitations can be attributed to the sluggish and uneven Li+ migration towards Li metal surface. Here, we report olefin-linked covalent organic frameworks (COFs) with electronegative channels for facilitating selective Li+ transport. The triazine rings and fluorinated groups of the COFs are introduced as electron-rich sites capable of enhancing salt dissociation and guiding uniform Li+ flux within the channels, resulting in a high Li+ transference number (0.85) and high ionic conductivity (1.78 mS cm-1 ). The COFs are mixed with a polymeric binder to form mixed matrix membranes. These membranes enable reliable Li plating/stripping cyclability over 700 h in Li/Li symmetric cells and stable capacity retention in Li/LiFePO4 cells, demonstrating its potential as a viable cationic highway for accelerating Li+ conduction.

9.
Angew Chem Int Ed Engl ; 62(42): e202310560, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37654107

RESUMO

The development of covalent organic frameworks (COFs) with efficient charge transport is of immense interest for applications in optoelectronic devices. To enhance COF charge transport properties, electroactive building blocks and dopants can be used to induce extended conduction channels. However, understanding their intricate interplay remains challenging. We designed and synthesized a tailor-made COF structure with electroactive hexaazatriphenylene (HAT) core units and planar dioxin (D) linkages, denoted as HD-COF. With the support of theoretical calculations, we found that the HAT units in the HD-COF induce strong, eclipsed π-π stacking. The unique stacking of HAT units and the weak in-plane conjugation of dioxin linkages leads to efficient anisotropic charge transport. We fabricated HD-COF films to minimize the grain boundary effect of bulk COFs, which resulted in enhanced conductivity. As a result, the HD-COF films showed an electrical conductivity as high as 1.25 S cm-1 after doping with tris(4-bromophenyl)ammoniumyl hexachloroantimonate.

10.
J Am Chem Soc ; 144(43): 19973-19980, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36239442

RESUMO

Developing covalent organic frameworks (COFs) with good electrical conductivity is essential to widen their range of practical applications. Thermal annealing is known to be a facile approach for enhancing conductivity. However, at higher temperatures, most COFs undergo amorphization and/or thermal degradation because of the lack of linker rigidity and physicochemical stability. Here, we report the synthesis of a conductive benzoxazole-linked COF/carbon hybrid material (BCOF-600C) by simple thermal annealing. The fused-aromatic benzoxazole and biphenyl building units endow the resulting COF with excellent physicochemical stability against high temperatures and strong acids/bases. This allows heat treatment to further enhance electrical conductivity with minimal structural alteration. The robust crystalline structure with periodically incorporated nitrogen atoms allowed platinum (Pt) atoms to be atomically integrated into the channel walls of BCOF-600C. The resulting electrocatalyst with well-defined active sites exhibited superior catalytic performance toward hydrogen evolution in acidic media.

11.
J Org Chem ; 86(21): 14398-14403, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34468134

RESUMO

Apart from being experimentally and theoretically interesting, tetraphenylene has potential applications in different fields, including supramolecular chemistry, material science, and asymmetric catalysis. Although a wide range of substituted tetraphenylenes have been reported, octaamine-based tetraphenylene derivatives have not been reported because of their instability. Here, stable octaaminotetraphenylene octahydrochloride is synthesized from the bromination of tetraphenylene to octabromotetraphenylene, which is subsequently aminated into octaiminotetraphenylene. Finally, the imino derivative is deprotected to yield octaaminotetraphenylene octahydrochloride.

12.
Int J Mol Sci ; 21(23)2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291425

RESUMO

Inflammation is a biological response of the immune system to defend the body from negative stimulation. However, the excessive inflammatory response can damage host tissues and pose serious threats. Exopolysaccharide (EPS), one of the postbiotics, is secreted from lactic acid bacteria. Although many studies have described the beneficial effects of EPS, such as its anti-inflammatory and anti-oxidant effects, its underlying mechanisms have remained to be poorly understood. Thus, we identified that EPS obtained from Lactobacillus plantarum L-14 was a homogeneous polysaccharide primarily comprised of glucose. To examine these anti-inflammatory effects, an inflammatory response was induced by lipopolysaccharide (LPS) administration to mouse macrophage RAW 264.7 cells that were pretreated with EPS. The anti-inflammatory effects of EPS were identified by analyzing the changes within inflammatory markers at the molecular level. We demonstrate here that EPS suppressed proinflammatory mediators, such as cyclooxygenase-2, interleukin-6, tumor necrosis factor-α, and interleukin-1ß, and downregulated the expression of an inducible nitric oxide synthase known to lead to oxidative stress. It was also confirmed that EPS had anti-inflammatory effects by blocking the interaction of LPS with Toll-like receptor 4 (TLR4), as demonstrated by using the known TLR4 inhibitor TAK-242. In addition, we found that EPS itself could suppress the expression of TLR4. Consequently, our data suggest that EPS can be a potential target for the development of natural product-derived medicine for treating inflammatory diseases related to TLR4.


Assuntos
Anti-Inflamatórios/farmacologia , Lactobacillus plantarum/química , Polissacarídeos Bacterianos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Células Cultivadas , Técnicas de Cocultura , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Ligação Proteica , Transporte Proteico , Células RAW 264.7
13.
Int J Mol Sci ; 21(2)2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32284513

RESUMO

Cell-penetrating peptides (CPPs) are defined by their ability to deliver cargo into cells and have been studied and developed as a promising drug-delivery system (DDS). However, the issue of whether the CPPs that have already entered the cells can be re-released or reused has not been studied. The purpose of this research was to construct CPP-conjugated human fibroblast growth factor 2 (hFGF2) and investigate whether they can be re-released from the cell membrane for reuse. This study combined hFGF2 with Tat or Ara27, a newly developed CPP derived from the zinc knuckle (CCHC-type) family protein of Arabidopsis. Human dermal fibroblast (HDF) was treated with Tat-conjugated hFGF2 (tFGF2) and Ara27-conjugated hFGF2 (NR-FGF2) for both long and short durations, and the effects on cell growth were compared. Furthermore, tFGF2 and NR-FGF2 re-released from the cells were quantified and the effects were evaluated by culturing HDF in a conditioned medium. Interestingly, the proliferation of HDF increased only when NR-FGF2 was treated for 1 h in endocytosis-independent manner. After 1 h, NR-FGF2 was significantly re-released, reaching a maximum concentration at 5 h. Furthermore, increased proliferation of HDF cultured in the conditioned medium containing re-released NR-FGF2 was discovered. While previous studies have focused on the delivery of cargo and its associated applications, this study has revealed that combinations of superior CPPs and therapeutics can be expected to prolong both the retention time and the cell-penetrating capacity, even in the presence of external factors. Therefore, CPPs can be applied in the context of topical drugs and cosmetics as a new DDS approach.


Assuntos
Peptídeos Penetradores de Células/metabolismo , Sistemas de Liberação de Medicamentos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Arabidopsis/genética , Membrana Celular/metabolismo , Peptídeos Penetradores de Células/administração & dosagem , Endocitose , Humanos
14.
Molecules ; 25(17)2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32859054

RESUMO

Human malignant melanoma is the most aggressive type of skin cancer with high metastatic ability. Despite several traditional therapies, the mortality rate remains high. Lactobacillus plantarum (L. plantarum), a species of lactic acid bacteria (LAB), is being studied for human health, including cancer treatment. However, few studies have elucidated the relationship between L. plantarum extract and human malignant melanoma. To investigate the effects of L. plantarum on human melanoma cells, A375 human melanoma cells were used and treated with L. plantarum L-14 extract. After the treatment, viability, migration ability, molecular changes of migration- and apoptosis-related genes, and the location of cytochrome c was evaluated. The L-14 extract inhibited the viability, migration of A375 cells as well as reduced expression of migration-related genes. In addition, it was confirmed that the L-14 extract induced intrinsic apoptosis in A375 cells. This study demonstrated that the L-14 extract exerted anticancer effects on A375 cells. Therefore, these data suggest that the L-14 extract is worth studying for the development of melanoma drugs using LAB.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Misturas Complexas/farmacologia , Lactobacillus plantarum/química , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Antineoplásicos/química , Linhagem Celular Tumoral , Misturas Complexas/química , Humanos , Melanoma/metabolismo , Melanoma/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
15.
J Am Chem Soc ; 141(30): 11786-11790, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31318202

RESUMO

Efficiently converting unstable linkages into stable linkages is an important objective in the chemistry of covalent organic frameworks (COFs), because it enhances stability and preserves crystallinity. Here, an unstable imine-linked COF was converted into a stable aromatic benzoxazole-linked COF (BO-COF) via post-oxidative cyclization, based on chemistry used to form fused-aromatic ladder-like rigid-rod polymers. The structure of the porous BO-COF was confirmed by transmission electron microscopy, infrared and solid-state nuclear magnetic resonance spectroscopies, powder X-ray diffraction patterns, and nitrogen adsorption-desorption isotherms. The efficient post-treatment of an unstable reversible COF converted it into a stable irreversible COF, which had significantly improved thermal and chemical stabilities as well as high crystallinity. This strategy can be universally applied for the synthesis of stable fused-aromatic COFs, expanding their practical applications.

16.
Proc Natl Acad Sci U S A ; 113(27): 7414-9, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27313207

RESUMO

The formation of 2D polyaniline (PANI) has attracted considerable interest due to its expected electronic and optoelectronic properties. Although PANI was discovered over 150 y ago, obtaining an atomically well-defined 2D PANI framework has been a longstanding challenge. Here, we describe the synthesis of 2D PANI via the direct pyrolysis of hexaaminobenzene trihydrochloride single crystals in solid state. The 2D PANI consists of three phenyl rings sharing six nitrogen atoms, and its structural unit has the empirical formula of C3N. The topological and electronic structures of the 2D PANI were revealed by scanning tunneling microscopy and scanning tunneling spectroscopy combined with a first-principle density functional theory calculation. The electronic properties of pristine 2D PANI films (undoped) showed ambipolar behaviors with a Dirac point of -37 V and an average conductivity of 0.72 S/cm. After doping with hydrochloric acid, the conductivity jumped to 1.41 × 10(3) S/cm, which is the highest value for doped PANI reported to date. Although the structure of 2D PANI is analogous to graphene, it contains uniformly distributed nitrogen atoms for multifunctionality; hence, we anticipate that 2D PANI has strong potential, from wet chemistry to device applications, beyond linear PANI and other 2D materials.

17.
Int J Mol Sci ; 20(3)2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30709061

RESUMO

Hyaline cartilage is a tissue of very low regenerative capacity because of its histology and limited nutrient supply. Cell-based therapies have been spotlighted in the regeneration of damaged cartilage. Dental pulp stem cells (DPSCs) are multipotent and are easily accessible for therapeutic purposes. In human gastrointestinal tracts, Enterococcus faecium is a naturally occurring commensal species of lactic acid bacteria. In this work, the human DPSCs were differentiated into chondrocytes using a chondrogenic differentiation medium with or without L-15 extract. We observed that chondrogenic differentiation improved in an E. faecium L-15 extract (L-15)-treated DPSC group via evaluation of chondrogenic-marker mRNA expression levels. In particular, we found that L-15 treatment promoted early-stage DPSC differentiation. Cells treated with L-15 were inhibited at later stages and were less likely to transform into hypertrophic chondrocytes. In L-15-treated groups, the total amount of cartilage extracellular matrix increased during the differentiation process. These results suggest that L-15 promotes chondrogenic differentiation, and that L-15 may be used for cartilage repair or cartilage health supplements. To our knowledge, this is the first report demonstrating the beneficial effect of L-15 treatment on chondrogenic differentiation.


Assuntos
Condrogênese , Meios de Cultura/farmacologia , Polpa Dentária/citologia , Enterococcus faecium/crescimento & desenvolvimento , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Sistema Livre de Células , Células Cultivadas , Meios de Cultura/química , Polpa Dentária/efeitos dos fármacos , Enterococcus faecium/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Marcadores Genéticos , Humanos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
18.
Angew Chem Int Ed Engl ; 57(13): 3415-3420, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29392856

RESUMO

A three-dimensional (3D) cage-like organic network (3D-CON) structure synthesized by the straightforward condensation of building blocks designed with gas adsorption properties is presented. The 3D-CON can be prepared using an easy but powerful route, which is essential for commercial scale-up. The resulting fused aromatic 3D-CON exhibited a high Brunauer-Emmett-Teller (BET) specific surface area of up to 2247 m2 g-1 . More importantly, the 3D-CON displayed outstanding low pressure hydrogen (H2 , 2.64 wt %, 1.0 bar and 77 K), methane (CH4 , 2.4 wt %, 1.0 bar and 273 K), and carbon dioxide (CO2 , 26.7 wt %, 1.0 bar and 273 K) uptake with a high isosteric heat of adsorption (H2 , 8.10 kJ mol-1 ; CH4 , 18.72 kJ mol-1 ; CO2 , 31.87 kJ mol-1 ). These values are among the best reported for organic networks with high thermal stability (ca. 600 °C).

19.
Angew Chem Int Ed Engl ; 57(28): 8438-8442, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29624829

RESUMO

There have been extensive efforts to synthesize crystalline covalent triazine-based frameworks (CTFs) for practical applications and to realize their potential. The phosphorus pentoxide (P2 O5 )-catalyzed direct condensation of aromatic amide instead of aromatic nitrile to form triazine rings. P2 O5 -catalyzed condensation was applied on terephthalamide to construct a covalent triazine-based framework (pCTF-1). This approach yielded highly crystalline pCTF-1 with high specific surface area (2034.1 m2 g-1 ). At low pressure, the pCTF-1 showed high CO2 (21.9 wt % at 273 K) and H2 (1.75 wt % at 77 K) uptake capacities. The direct formation of a triazine-based COF was also confirmed by model reactions, with the P2 O5 -catalyzed condensation reaction of both benzamide and benzonitrile to form 1,3,5-triphenyl-2,4,6-triazine in high yield.

20.
Eur Radiol ; 27(3): 1136-1147, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27380904

RESUMO

OBJECTIVES: To evaluate the feasibility of a double-acquisition coronary CT angiography (CCTA) protocol in the presence and absence of an intravenous (IV) vasodilator infusion for detecting vasospastic angina. METHODS: Twenty patients with a high clinical probability of vasospastic angina were enrolled. All subjects underwent baseline CCTA without a vasodilator in the early morning followed by a catheterized coronary angiography with ergonovine provocation test. Within 3 days, all subjects underwent repeat CCTA during a continuous IV infusion of nitrate. Vasospastic angina as detected by CCTA was defined as significant stenosis (≥50 %) with negative remodelling without definite plaques or diffuse small diameter (<2 mm) of a major coronary artery with a beaded appearance on baseline CT that completely dilated on IV nitrate CT. The CCTA results were compared to the catheterized ergonovine provocation test as the reference standard. RESULTS: Among 20 patients, the catheterized ergonovine provocation test detected vasospasm in 15 patients. The sensitivity, specificity, positive predictive value and negative predictive value of CCTA in a per-patient-based analysis were 73, 100, 100 and 56 %, respectively. CONCLUSIONS: Double-acquisition CCTA in the presence and absence of IV infusion of nitrate allows noninvasive detection of vasospastic angina with moderate sensitivity and high specificity. KEY POINTS: • Limited data exist regarding the efficacy of CCTA in detecting vasospastic angina. • We propose a double-acquisition CCTA protocol with and without IV nitrate injections. • This protocol provides 100% specificity and moderate sensitivity (73%) in spasm detection.


Assuntos
Angina Pectoris/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Vasoespasmo Coronário/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/etiologia , Ergonovina , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Vasodilatadores
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