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1.
Chempluschem ; 85(4): 641-652, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32237227

RESUMO

Many methods have been developed for attaching an alcohol functionality to a solid support. However, not all of these methods are used to obtain peptide alcohols. In this Minireview, we will discuss several of the most important methods and approaches for the synthesis of peptide alcohols and the attachment of hydroxy groups to a solid support for the synthesis of cyclic peptides. Some of the methods include the use of functionalized Wang resin and the attachment of an alcohol to an enol ether resin. We also discuss the use of the chlorotrityl resin, one of the most common linkers used to obtain peptide alcohols. In addition, we outline the recently developed resins with the Rink, Ramage and Sieber handles. The majority of these methods have been used to synthesize many important drugs, such as octreotide and the antibiotic peptaibols.

2.
Nanoscale ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32227042

RESUMO

Nanoparticles (NPs) enter a cell primarily via endocytosis, during which they are engulfed by the cell and reside in lipid vesicles named endosomes. Apart from when an endosome is pinched off the plasma membrane, structural integrity of its lipid membrane is usually well maintained. Under certain circumstances, however, such structural integrity can be considerably perturbed by a nanoparticle. For instance, recent experiments [Chu et al., Sci. Rep., 2014, 4, 4495] indicate that nanodiamonds with sharp corners can escape from an endosome by piercing its lipid membrane. Nonetheless, the energetics of this behavior and how it may be controlled by membrane adhesion and NP morphology remain unclear. In this work, we employ continuum modeling to investigate membrane pore formation induced by the spontaneous binding of a sharp nanoparticle. Based on two axial-symmetric NP models, we characterize the indispensable role played by curvature heterogeneity, membrane adhesion, and the sharpness as well as the size of a nanoparticle in 'breaking' a lipid membrane. Apart from revealing a general mechanism of NP binding-induced membrane pore formation, our results provide the reference for improving the endosomal escape of nanoparticles through manipulating their morphology, a direction that can be explored either independently or combined with existing strategies targeting NP surface chemistry.

3.
Inflammation ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130574

RESUMO

Injurious mechanical ventilation has been shown to directly affect pulmonary and systemic immune responses. How these responses propagate or attenuate remains unknown. The goal of this study was to further determine whether toll-like receptor (TLR) 4 and WNT1-inducible signaling pathway protein 1 (WISP1) could contribute to injurious mechanical ventilation, especially focusing on the role of macrophages during experimental ventilator-induced lung injury. A prospective, randomized, and controlled animal study was designed, and male, wild-type (WT) C57BL/6 mice, TLR4 knockout (TLR4-/-), and lyzTLR4 knockout (lyzTLR4-/-) mice aging 8~12 weeks were used. Animals were anesthetized and randomized to spontaneous breathing (SB) group or to high tidal volume (VT, 20 ml/kg) mechanical ventilation (HTV) group. Histological evaluation, alveolar-capillary permeability of Evan's blue albumin (EBA), WISP1 protein levels, macrophage inflammatory protein-2 (MIP-2), and interleukin-6 (IL-6) in plasma and bronchoalveolar lavage fluid (BALF) concentrations were analyzed. HTV group was associated with a significant increase of WISP1 and EBA ratio in C57BL/6 mice, a significant decrease of WISP1 protein levels, and a significant decrease of IL-6, MIP-2 in plasma, and BALF concentrations of pro-inflammatory cytokines in TLR4-/- and lyzTLR4-/- knockout mice. In TLR4-/- mice and lyzTLR4-/- mice, there were also significant differences between SB group and HTV group in terms of H&E score and EBA ratio and level of pro-inflammation cytokines. The entire TLR4-targeted mice could further improve various inflammatory changes and damages when compared with lyzTLR4-targeted mice. What is more, TLR4-/- mice and lyzTLR4-/- mice reacted differently to rWISP1 and/or BMMC treated. TLR4-/- mice had no response to rWISP1, while lyzTLR4-/- mice still showed drastic response to both treatments. TLR4 and WISP1, especially the former one, on macrophages could contribute to releasing of pro-inflammatory cytokines during ventilator-induced lung injury. Injurious mechanical ventilation may result in an immune response which is similar to that of infection.

4.
Sci Adv ; 6(12): eaaw5790, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32206705

RESUMO

Atmospheric nitrogen (N) deposition affects the greenhouse gas (GHG) balance of ecosystems through the net atmospheric CO2 exchange and the emission of non-CO2 GHGs (CH4 and N2O). We quantified the effects of N deposition on biomass increment, soil organic carbon (SOC), and N2O and CH4 fluxes and, ultimately, the net GHG budget at ecosystem level of a Moso bamboo forest in China. Nitrogen addition significantly increased woody biomass increment and SOC decomposition, increased N2O emission, and reduced soil CH4 uptake. Despite higher N2O and CH4 fluxes, the ecosystem remained a net GHG sink of 26.8 to 29.4 megagrams of CO2 equivalent hectare-1 year-1 after 4 years of N addition against 22.7 hectare-1 year-1 without N addition. The total net carbon benefits induced by atmospheric N deposition at current rates of 30 kilograms of N hectare-1 year-1 over Moso bamboo forests across China were estimated to be of 23.8 teragrams of CO2 equivalent year-1.

5.
J Comput Assist Tomogr ; 44(2): 305-309, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195810

RESUMO

PURPOSE: The purpose of this study was to assess the diagnostic yield of computed tomography (CT)-guided core needle biopsy (CNB) for initial transbronchial biopsy (TBB)-based nondiagnostic lung lesions. METHODS: From January 2014 to December 2017, 101 consecutive patients with initial TBB-based nondiagnostic lung lesions underwent CT-guided CNB. All procedures were performed with an 18G core needle by a chest radiologist with more than 5 years of experience. The CT-guided CNB was performed within 30 days after the initial TBB. In total, 90 and 11 central and peripheral lung lesions were observed, respectively. The mean ± SD diameter of these lesions was 58.8 ± 21.8 mm. The diagnostic yield of CT-guided CNB was assessed. RESULTS: Computed tomography-guided CNB provided a definite diagnosis for 63 (62.4%) of the 101 lesions. The 63 CNB-based lesion diagnoses included malignant (n = 57) and specific benign (n = 6) lesions. The remaining 38 CNB-based nondiagnostic lesions included nonspecific benign (n = 35) and suspected malignant (n = 3) lesions. The 38 CNB-based nondiagnostic lesions were confirmed by surgery (n = 5), repeat CNB (n = 5), or CT follow-up (n = 28). The mean ± SD follow-up was 9.9 ± 7.3 months. Based on the final diagnosis, 67 lesions were malignant and 34 lesions were benign. The sensitivity, specificity, and accuracy of CT-guided CNB were 89.6% (60/67), 100% (34/34), and 93.1% (94/101), respectively. CONCLUSIONS: Computed tomography-guided CNB is a useful diagnostic modality for accurate diagnosis of lung lesions with inconclusive pathologic results after initial TBB.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Biópsia Guiada por Imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
J Neuroinflammation ; 17(1): 85, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32178691

RESUMO

BACKGROUND: A growing body of studies have indicated that bone marrow mesenchymal stem cells (BMSCs) have powerful analgesic effects in animal models of bone cancer pain. Here, we explored the molecular mechanisms underlying how BMSCs alleviate pain sensation in a mouse model of bone cancer pain. METHODS: C3H/HeN adult male mice were used to generate a bone cancer pain model. BMSCs were isolated from mouse bone marrow, modified by transfection with microRNA-9-5p (miR-9-5p), and infused into the spinal cord. Spontaneous flinches, paw withdrawal latency, limb-use score, and weight-bearing score were used to assess pain-related behaviors. ELISA, RT-PCR, western blot, and luciferase assay were used to assess gene expressions. RESULTS: Our results show that miR-9-5p regulated the expression of both repressor element silencing transcription factor (REST) and µ-opioid receptors (MOR) by targeting REST in primary mouse BMSCs. Overexpression of miR-9-5p reversed the activation of inflammatory pathway in TNF-α- and IL-6-treated BMSCs. In addition, miR-9-5p modified BMSCs alleviated cancer pain in the sarcoma-inoculated mouse model. MiR-9-5p modified BMSCs suppressed cytokine expression in the spinal cord of sarcoma-inoculated mice by suppressing REST gene expression. CONCLUSIONS: Our results indicate that miR-9-5p modified BMSCs can relieve bone cancer pain via modulating neuroinflammation in the central nervous system, suggesting genetically modified BMSCs could be a promising cell therapy in pain management.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32196893

RESUMO

Light-harvesting system is an important way for capturing, transferring and utilizing light energy, while it remains a key challenge to develop highly efficient artificial light-harvesting systems. Herein, we report a supramolecular co-assembly based on lower-rim dodecyl-modified sulfonatocalix[4]arene (SC4AD) and naphthyl-1,8-diphenyl pyridinium derivative (NPS) as a light-harvesting platform. NPS as a donor shows significant aggregation induced emission enhancement (AIEE) after assembling with SC4AD. Upon introduction of Nile blue (NiB) as an acceptor into the NPS-SC4AD co-assembly, the light-harvesting system becomes near-infrared (NIR) emissive (675 nm). Importantly, the NIR emitting NPS-SC4AD-NiB system exhibits an ultrahigh antenna effect (33.1) at a high donor/acceptor ratio (250:1). By co-staining PC-3 cells with a Golgi staining reagent, NBD C6-ceramide, NIR imaging in Golgi apparatus has been demonstrated using these NIR emissive nanoparticles.

8.
Nanoscale ; 12(10): 5746-5763, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32124894

RESUMO

Vaccines harness the inherent properties of the immune system to prevent diseases or treat existing ones. Continuous efforts have been devoted to both gaining a mechanistic understanding of how the immune system operates and designing vaccines with high efficacies and effectiveness. Advancements in nanotechnology in recent years have generated unique opportunities to meet the daunting challenges associated with immunology and vaccine development. Firstly, nanoparticle formulated systems provide ideal model systems for studying the operation of the immune system, making it possible to systematically identify key factors and understand their roles in specific immune responses. Also, the versatile compositions/architectures of nanoparticle systems enable new strategies/novel platforms for developing vaccines with high efficacies and effectiveness. In this review, we discuss the advantages of nanoparticles and the challenges faced during vaccine development, through the framework of the immunological mechanisms of vaccination, with the aim of bridging the gap between immunology and materials science, which are both involved in vaccine design. The knowledge obtained provides general guidelines for future vaccine development.

9.
Neurogastroenterol Motil ; : e13832, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32134545

RESUMO

BACKGROUND: Achalasia is an esophageal motility disorder with unknown etiology. Previous findings indicate that immune-mediated inflammatory process causes inhibitory neuronal degeneration. This study was designed to evaluate levels of serological cytokines and chemokines in patients with achalasia. METHODS: We collected information from forty-seven patients with achalasia who underwent peroral endoscopic myotomy. Control samples were collected from forty-seven age- and sex-matched healthy people. The concentrations of serological cytokines and chemokines were analyzed by Luminex xMAP immunoassay. Serological and clinical data were compared between groups. KEY RESULTS: Compared with healthy controls, achalasia patients had significantly increased concentrations of eleven cytokines and chemokines, namely, TGF-ß1 (P < .001), TGF-ß2 (P < .001), TGF-ß3 (P < .001), IL-1ra (P < .001), IL-17 (P = .005), IL-18 (P < .001), IFN-γ (P < .001), MIG (P < .001), PDGF-BB (P < .001), IP-10 (P = .003), and SCGF-B (P < .001). Gene ontology (GO) and network functional enrichment analysis revealed regulation of signaling receptor activity and receptor-ligand activity were the most related pathways of these cytokines and chemokines. Levels of twelve cytokines and chemokines were significantly increased in type III compared with I/II achalasia, namely, TGF-ß2, IL-1ra, IL-2Ra, IL-18, MIG, IFN-γ, SDF-1a, Eotaxin, PDGF-BB, IP-10, MCP-1, and TRAIL. CONCLUSIONS AND INFERENCES: Patients with achalasia exhibited increased levels of serological cytokines and chemokines. Levels of cytokines and chemokines were significantly increased in type III than in type I/II achalasia. Cytokines and chemokines might contribute to the inflammatory development of achalasia.

10.
Oncologist ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167195

RESUMO

Immune checkpoint inhibitor (ICI)-induced immune-related adverse events (irAEs) may affect almost any organ system and occur at any point during therapy. Autoantibody analysis may provide insight into the mechanism, nature, and timing of these events. We report a case of ICI-induced late-onset Raynaud's-like phenomenon in a patient receiving combination immunotherapy. A 53-year-old woman with advanced non-small lung cancer received combination anti-cytotoxic T-lymphocyte antigen 4 and anti-programmed death 1 ICI therapy. She developed early (hypophysitis at 4 months) and late (Raynaud's at >20 months) irAEs. Longitudinal assessment of 124 autoantibodies was correlated with toxicity. Although autoantibody levels were generally stable for the first 18 months of therapy, shortly before the development of Raynaud's, a marked increase in multiple autoantibodies was observed. This case highlights the potential for delayed autoimmune toxicities and provides potential biologic insights into the dynamic nature of these events. KEY POINTS: A patient treated with dual anti-PD1 and anti-CTLA4 therapy developed Raynaud's-like signs and symptoms more than 18 months after starting therapy. In this case, autoantibody changes became apparent shortly before onset of clinical toxicity. This case highlights the potential for late-onset immune-related adverse events checkpoint inhibitors, requiring continuous clinical vigilance. The optimal duration of checkpoint inhibitor therapy in patients with profound and prolonged responses remains unclear.

11.
Org Lett ; 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32142304

RESUMO

We have developed a novel π-π interaction and dual H-bond concerted control strategy to construct axially chiral naphthylamine heterocycles. With ortho-alkynyl-naphthylamines as the electrophile, indoles and 4-hydroxycoumarins were efficiently employed to construct axially chiral skeletons in good yields and with excellent enantioselectivities (up to 97% enantiomeric excess). Furthermore, the resulting products could be converted to potential squaramides featuring organic catalysts.

12.
Sci Rep ; 10(1): 3745, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111951

RESUMO

During mung bean post-germination seedling growth, various metabolic and physiological changes occurred, leading to the improvement of its nutritional values. Here, transcriptomic and metabolomic analyses of mung bean samples from 6-hour, 3-day and 6-day after imbibition (6-HAI, 3-DAI, and 6-DAI) were performed to characterize the regulatory mechanism of the primary metabolites during the post-germination seedling growth. From 6-HAI to 3-DAI, rapid changes in transcript level occurred, including starch and sucrose metabolism, glycolysis, citrate cycle, amino acids synthesis, and plant hormones regulation. Later changes in the metabolites, including carbohydrates and amino acids, appeared to be driven by increases in transcript levels. During this process, most amino acids and monosaccharides kept increasing, and accumulated in 6-day germinated sprouts. These processes were also accompanied with changes in hormones including abscisic acid, gibberellin, jasmonic acid, indole-3-acetic acid, etc. Overall, these results will provide insights into molecular mechanisms underlying the primary metabolic regulation in mung bean during post-germination seedling growth.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32127483

RESUMO

The anomalous nondipolar and nonaxisymmetric magnetic fields of Uranus and Neptune have long challenged conventional views of planetary dynamos. A thin-shell dynamo conjecture captures the observed phenomena but leaves unexplained the fundamental material basis and underlying mechanism. Here we report extensive quantum-mechanical calculations of polymorphism in the hydrogen-oxygen system at the pressures and temperatures of the deep interiors of these ice giant planets (to >600 GPa and 7,000 K). The results reveal the surprising stability of solid and fluid trihydrogen oxide (H3O) at these extreme conditions. Fluid H3O is metallic and calculated to be stable near the cores of Uranus and Neptune. As a convecting fluid, the material could give rise to the magnetic field consistent with the thin-shell dynamo model proposed for these planets. H3O could also be a major component in both solid and superionic forms in other (e.g., nonconvecting) layers. The results thus provide a materials basis for understanding the enigmatic magnetic-field anomalies and other aspects of the interiors of Uranus and Neptune. These findings have direct implications for the internal structure, composition, and dynamos of related exoplanets.

14.
Sci Rep ; 10(1): 4925, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188927

RESUMO

Chronic plaque psoriasis and psoriatic arthritis are multifactorial inter-related diseases with strong genetic contributions. Better elucidation of the heritability of psoriatic disease subsets is important for identifying novel genes, risk stratification and potential clinical applications. In this study, we used two mixed-effect modelling methodologies to assess the additive contribution of common single nucleotide polymorphisms from genome-wide association studies to estimate the heritability of cutaneous psoriasis, psoriasis vulgaris and psoriatic arthritis. We found that cutaneous psoriasis and psoriatic arthritis both exhibit considerable heritability, with a greater contribution coming from cutaneous psoriasis.

15.
Medicine (Baltimore) ; 99(7): e18837, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049785

RESUMO

Patients with cirrhosis are known to develop small bowel mucosal lesions. However, the occurrence of mucosal lesions in patients with abnormal liver function test results in the absence of chronic liver disease has not been fully evaluated. This study aims to examine the association between small bowel endoscopic lesions and liver dysfunction in patients without confirmed chronic liver disease.Two hundred ninety six consecutive patients who met the selection criteria underwent capsule endoscopy. The severity of the small intestinal mucosal lesions was evaluated quantitatively using the Lewis scoring system, and hepatic dysfunction was evaluated using an algorithm-based combination scoring system with 8 individual serological markers.Small bowel lesions were observed in 121 patients (40.88%). Hepatic dysfunction was significantly more prevalent in patients with small bowel lesions than in those without lesions (33.1%; 40/121 and 5.7%; 10/175, respectively; P < .001). The mean serum ALT and AST levels were significantly higher in patients with small bowel lesions than in those without lesions (P = .007 and P = .004, respectively). The mean scores for AST to Platelet Ratio Index, Forns Index, S-Index, Fibrosis-4 Index and BARD were significantly higher in patients with small bowel lesions than those without lesions. The Lewis score significantly and positively correlated with the Forns Index (P = .008) and the FIB-4 Index (P = .006).There is a close correlation between small intestinal mucosal lesions and hepatic dysfunction. The severity of hepatic dysfunction is directly proportional to the severity of the small intestinal mucosal lesions in patients without confirmed chronic liver disease.


Assuntos
Mucosa Intestinal/patologia , Intestino Delgado/patologia , Hepatopatias/epidemiologia , Adulto , Idoso , Endoscopia por Cápsula , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Projetos de Pesquisa , Estudos Retrospectivos
16.
Nature ; 579(7797): 67-72, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32094661

RESUMO

The Hall-Petch relationship, according to which the strength of a metal increases as the grain size decreases, has been reported to break down at a critical grain size of around 10 to 15 nanometres1,2. As the grain size decreases beyond this point, the dominant mechanism of deformation switches from a dislocation-mediated process to grain boundary sliding, leading to material softening. In one previous approach, stabilization of grain boundaries through relaxation and molybdenum segregation was used to prevent this softening effect in nickel-molybdenum alloys with grain sizes below 10 nanometres3. Here we track in situ the yield stress and deformation texturing of pure nickel samples of various average grain sizes using a diamond anvil cell coupled with radial X-ray diffraction. Our high-pressure experiments reveal continuous strengthening in samples with grain sizes from 200 nanometres down to 3 nanometres, with the strengthening enhanced (rather than reduced) at grain sizes smaller than 20 nanometres. We achieve a yield strength of approximately 4.2 gigapascals in our 3-nanometre-grain-size samples, ten times stronger than that of a commercial nickel material. A maximum flow stress of 10.2 gigapascals is obtained in nickel of grain size 3 nanometres for the pressure range studied here. We see similar patterns of compression strengthening in gold and palladium samples down to the smallest grain sizes. Simulations and transmission electron microscopy reveal that the high strength observed in nickel of grain size 3 nanometres is caused by the superposition of strengthening mechanisms: both partial and full dislocation hardening plus suppression of grain boundary plasticity. These insights contribute to the ongoing search for ultrastrong metals via materials engineering.

17.
J Phys Chem Lett ; : 1614-1621, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32048850

RESUMO

Lubrication plays a pivotal role in reducing energy consumption and machinery wear, profoundly impacting technological and economic development and the environment. A recent study ( Erdemir , A. , et al. Nature 2016 , 536 , 67 ) reported the effective extraction of carbon-based tribofilms from lubricating oil by catalytic activation of the coating material, opening new possibilities for innovative lubrication material research and development. Here, we showcase a solute-atom-strengthened and catalytically functionalized coating design and demonstrate its implementation in a TiN-Ag solid solution film that exhibits concurrent ultralow friction and ultralow wear. Indentation tests and Raman and X-ray photoelectron spectroscopy combined with quantum mechanical simulations uncover the rare superhard nature of the TiN-Ag film along with a solute-Ag-atom-induced self-oxidation mechanism for its outstanding catalytic capacity. These findings identify an outstanding type of mechanically strong and catalytically active coating material with simultaneous superior protective and lubricating functionality, holding great promise for applications ranging from microdevices to large-scale industrial equipment.

18.
J Reprod Dev ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32051348

RESUMO

Changes in histone modifications always correlate with altered transcriptional activities of genes. Recent studies have shown that the mutation of certain lysine residues to methionine in the histone variant H3.3 can act as a valuable tool to reduce specific H3 methylation levels. In our study, we used the mouse spermatogenic cell line GC-2 as a model to generate cells stably expressing H3.3 K4, H3.3 K9, H3.3 K27, and H3.3 K36M. The expression of these H3.3 K-to-M mutants influenced the expression of different subsets of genes, and a total of 891 differentially expressed genes were identified through global gene expression profiling. Moreover, the H3.3 K-to-M transgenes, especially H3.3 K36M, impacted the expression of endogenous retrovirus ERVK. This study gives a global view of how different H3 modifications regulate transcriptomes in spermatogenic cell lines, and identifies potential targets of H3 modifications in male germ line.

19.
Chemphyschem ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040267

RESUMO

As the first discovered organoboron compound with photochromic property, B(ppy)Mes2 (ppy=2-phenylpyridine, Mes=mesityl) displays rich photochemistry that constitutes a solid foundation for wide applications in optoelectronic fields. In this work, we investigated the B(ppy)Mes2 to borirane isomerization mechanisms in the three lowest electronic states (S0 , S1 , and T1 ) based on the complete active space self-consistent field (CASSCF) and its second-order perturbation (CASPT2) methods combined with time-dependent density functional theory (TD-DFT) calculations. Our results show that the photoisomerization in the S1 state is dominant, which is initiated by the cleavage of the B-Cppy bond. After overcoming a barrier of 0.5 eV, the reaction pathway leads to a conical intersection between the S1 and S0 states (S1 /S0 )x , from which the decay path may go back to the reactant B(ppy)Mes2 via a closed-shell intermediate (Int1-S0 ) or to the product borirane via a biradical intermediate (Int2-S0 ). Although triplet states are probably involved in the photoinduced process, the possibility of the photoisomerization in T1 state is very small owing to the weakly allowed S1 →T1 intersystem crossing and the high energy barrier (0.77 eV). In addition, we found the photoisomerization is thermally reversible, which is consistent with the experimental observations.

20.
J Cardiothorac Surg ; 15(1): 38, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087712

RESUMO

BACKGROUND: Patients with DeBakey type II aortic dissection or ascending aortic aneurysms involving the right innominate artery require hemiarch replacement and placement of a right innominate artery graft. Traditional aortic hemiarch replacement surgery must be performed under right axillary artery cannulation perfusion and moderate or deep hypothermia circulatory arrest. However, the axillary artery perfusion is always associated with left subclavian artery "steal blood", and it cannot guarantee blood supply to the left cerebral hemisphere in patients with an incomplete circle of Willis, and hypothermia and hypoperfusion cause damage to the brain and spinal cord; therefore, postoperative complications of the nervous system are common. Herein, we present a hemiarch replacement procedure with the use of the single branch-first combined with the mid-arch clamping technique. This procedure can not only reduce the axillary artery incision but also eliminate the need for mid-deep hypothermia and circulatory arrest. CASE PRESENTATION: A 41-year-old male patient underwent surgery with this technique. Computed tomography angiography performed upon admission showed calcified plaques scattered throughout the aorta and showed DeBakey type II aortic dissection involving the right innominate artery, accompanied by cardiac tamponade. The patient underwent aortic root repair, ascending aorta replacement, and hemiarch replacement as well as the placement of a right innominate artery graft. Aortic root anastomosis was performed with the embedded anastomosis technique. There were no postoperative complications. The patient was discharged 11 days after the operation. During more than 3 months of follow-up, there were no cases of aortic valve regurgitation or anastomotic fistula. CONCLUSIONS: The single branch-first combined with the mid-arch clamping technique for the right innominate artery can reduce the axillary artery incision and avoid damage to the body under mid-deep hypothermia and circulatory arrest. The embedded anastomosis technique is easy to perform, results in a limited amount of bleeding and requires almost no extra needling. We believe that these techniques can serve as good alternative strategies for patients with DeBakey type II aortic dissection or ascending aortic aneurysms involving the right innominate artery.

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