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1.
Apoptosis ; 29(1-2): 243-266, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37670104

RESUMEN

A particular GTPase-activating protein called RACGAP1 is involved in apoptosis, proliferation, invasion, metastasis, and drug resistance in a variety of malignancies. Nevertheless, the role of RACGAP1 in pan-cancer was less studied, and its value of the expression and prognostic of nasopharyngeal carcinoma (NPC) has not been explored. Hence, the goal of this study was to investigate the oncogenic and immunological roles of RACGAP1 in various cancers and its potential value in NPC. We comprehensively analyzed RACGAP1 expression, prognostic value, function, methylation levels, relationship with immune cells, immune infiltration, and immunotherapy response in pan-cancer utilizing multiple databases. The results discovered that RACGAP1 expression was elevated in most cancers and suggested poor prognosis, which could be related to the involvement of RACGAP1 in various cancer-related pathways such as the cell cycle and correlated with RACGAP1 methylation levels, immune cell infiltration and reaction to immunotherapy, and chemoresistance. RACGAP1 could inhibit anti-tumor immunity and immunotherapy responses by fostering immune cell infiltration and cytotoxic T lymphocyte dysfunction. Significantly, we validated that RACGAP1 mRNA and protein were highly expressed in NPC. The Gene Expression Omnibus database revealed that elevated RACGAP1 expression was associated with shorter PFS in patients with NPC, and RACGAP1 potentially influenced cell cycle progression, DNA replication, metabolism, and immune-related pathways, resulting in the recurrence and metastasis of NPC. This study indicated that RACGAP1 could be a potential biomarker in pan-cancer and NPC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Apoptosis/genética , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Neoplasias Nasofaríngeas/genética
2.
Opt Lett ; 49(3): 486-489, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300040

RESUMEN

We propose a scheme for generating nonreciprocal strong mechanical squeezing by using two-tone lasers to drive a spinning optomechanical system. For given driving frequencies, strong mechanical squeezing of the breathing mode in the spinning resonator can be achieved in a chosen driving direction but not in the other. The nonreciprocity originates from the Sagnac effect caused by the resonator's spinning. We also find the classical nonreciprocity and the quantum nonreciprocity can be switched by simply changing the angular velocity of the spinning resonator. We show that the scheme is robust to the system's dissipations and the mechanical thermal noise. This work may be meaningful for the study of nonreciprocal device and quantum precision measurement.

3.
J Natl Compr Canc Netw ; 22(5): 331-357, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-39019058

RESUMEN

Breast cancer is treated with a multidisciplinary approach involving surgical oncology, radiation oncology, and medical oncology. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer include recommendations for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget's disease, Phyllodes tumor, inflammatory breast cancer, and management of breast cancer during pregnancy. The content featured in this issue focuses on the recommendations for overall management of systemic therapy (preoperative and adjuvant) options for nonmetastatic breast cancer. For the full version of the NCCN Guidelines for Breast Cancer, visit NCCN.org.


Asunto(s)
Neoplasias de la Mama , Humanos , Neoplasias de la Mama/terapia , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Oncología Médica/normas , Oncología Médica/métodos , Terapia Combinada/normas
4.
Microb Cell Fact ; 23(1): 123, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724968

RESUMEN

BACKGROUND: Saccharomyces cerevisiae is an important microorganism in ethanol synthesis, and with sugarcane molasses as the feedstock, ethanol is being synthesized sustainably to meet growing demands. However, high-concentration ethanol fermentation based on high-concentration sugarcane molasses-which is needed for reduced energy consumption of ethanol distillation at industrial scale-is yet to be achieved. RESULTS: In the present study, to identify the main limiting factors of this process, adaptive laboratory evolution and high-throughput screening (Py-Fe3+) based on ARTP (atmospheric and room-temperature plasma) mutagenesis were applied. We identified high osmotic pressure, high temperature, high alcohol levels, and high concentrations of K+, Ca2+, K+ and Ca2+ (K+&Ca2+), and sugarcane molasses as the main limiting factors. The robust S. cerevisiae strains of NGT-F1, NGW-F1, NGC-F1, NGK+, NGCa2+ NGK+&Ca2+-F1, and NGTM-F1 exhibited high tolerance to the respective limiting factor and exhibited increased yield. Subsequently, ethanol synthesis, cell morphology, comparative genomics, and gene ontology (GO) enrichment analysis were performed in a molasses broth containing 250 g/L total fermentable sugars (TFS). Additionally, S. cerevisiae NGTM-F1 was used with 250 g/L (TFS) sugarcane molasses to synthesize ethanol in a 5-L fermenter, giving a yield of 111.65 g/L, the conversion of sugar to alcohol reached 95.53%. It is the highest level of physical mutagenesis yield at present. CONCLUSION: Our results showed that K+ and Ca2+ ions primarily limited the efficient production of ethanol. Then, subsequent comparative transcriptomic GO and pathway analyses showed that the co-presence of K+ and Ca2+ exerted the most prominent limitation on efficient ethanol production. The results of this study might prove useful by promoting the development and utilization of green fuel bio-manufactured from molasses.


Asunto(s)
Calcio , Etanol , Fermentación , Melaza , Potasio , Saccharomyces cerevisiae , Saccharum , Etanol/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharum/metabolismo , Calcio/metabolismo , Potasio/metabolismo
5.
Analyst ; 149(7): 2045-2050, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38407274

RESUMEN

Copper ions (Cu2+) play an essential role in various cellular functions, including respiration, nerve conduction, tissue maturation, oxidative stress defense, and iron metabolism. Covalent organic frameworks (COFs) are a class of porous crystalline materials with directed structural designability and high stability due to the combination of different monomers through covalent bonds. In this study, we synthesized a porphyrin-tetrathiazole COF (TT-COF(Zn)) with Zn-porphyrin and tetrathiafulvalene (TTF) as monomers and used it as a photoactive material. The strong light absorption of metalloporphyrin and the electron-rich properties of supplied TTF contribute to its photoelectrochemical performance. Additionally, the sulfur (S) in the TTF can coordinate with Cu2+. Based on these properties, we constructed a highly sensitive photoelectrochemical sensor for detecting Cu2+. The sensor exhibited a linear range from 0.5 nM to 500 nM (R2 = 0.9983) and a detection limit of 0.15 nM for Cu2+. Notably, the sensor performed well when detecting Cu2+ in water samples.

6.
Inorg Chem ; 63(13): 6033-6041, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38500387

RESUMEN

We report the synthesis and structural characterization of a 2D metal-organic framework with AB-packing layers, [Co2(pybz)2(CH3COO)2]·DMF (Co2, pybz= 4-(4-pyridyl)benzoate), containing a stable (4,4)-grid network fabricated by paddle-wheel nodes, ditopic pybz, and acetate ligands. After removal of the guest, the layer structure is retained but reorganized into an ABCD packing mode in the activated phase (Co2a). Consequently, the intralayer square windows (7.2 × 5.0 Å2) close, while the interlayer separation is decreased slightly from 3.69 to 3.45 Å, leaving a narrow gap. Importantly, the dangling methyl group of the acetate with H-bonds to the adjacent layers and also the well-distributed π-π interactions between the aromatic rings of neighboring layers facilitate the structural stability. These weak supramolecular interactions further allow for favorable dynamic exfoliation of the layers, which promotes efficient adsorption of C2H2 (41.6 cm3 g-1) over CO2 with an adsorption ratio of 6.3 (0.5 bar, 298 K). The effective separation performance of equimolar C2H2/CO2 was verified by cycling breakthrough experiments and was even tolerable to moisture (R.H = 52%). DFT calculations, in situ PXRD, and PDF characterization reveal that the favorable retention of C2H2 rather than that of CO2 is due to its H-bond formation with the paddle-wheel oxygen atoms that triggers the increase in interlayer separation during C2H2 adsorption.

7.
Bioorg Med Chem ; 97: 117544, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38071943

RESUMEN

It's urgent to discover new antibiotics along with the increasing emergence and dissemination of multidrug resistant (MDR) bacterial pathogens. In the present investigation, morusin exhibited rapid bactericidal activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) by targeting the phospholipid of bacterial inner membrane, increasing membrane rigidity and disrupting bacterial homeostasis together with the membrane permeability, which caused fundamental metabolic disorders. Furthermore, morusin can also accumulate ROS, suppress H2S production, and aggravate oxidative damage in bacteria. Importantly, morusin also inhibited the spread of wounds and reduced the bacterial burden in the mouse model of skin infection caused by MRSA. It's a chance to meet the challenge of existing antibiotic resistance and avoid the development of bacterial resistance, given the multiple targets of morusin.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Morus , Animales , Ratones , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana
8.
J Nat Prod ; 87(8): 2004-2013, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39033408

RESUMEN

Seven new formononetin derivatives (1-7) were designed and prepared from formononetin (phase II phytoestrogen). The derivatives 9-butyl-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (2) and 9-(furan-3-ylmethyl)-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (7) promoted significant osteoblast formation by modulating the BMP/Smad pathway. Compound 7 exhibited potent antiosteoclastogenesis activity in RANKL-induced RAW264.7 cells and ovariectomy (OVX)-induced osteoporosis in mice by regulation of the RANK/RANKL/OPG pathway. Compound 7 regulated osteoblast and osteoclast simultaneously and showed better effect than the well-known drug ipriflavone in vivo, suggesting 7 as a patented antiosteoporosis candidate.


Asunto(s)
Isoflavonas , Osteoblastos , Osteoclastos , Osteoporosis , Ligando RANK , Isoflavonas/farmacología , Isoflavonas/química , Animales , Osteoblastos/efectos de los fármacos , Ratones , Osteoporosis/tratamiento farmacológico , Osteoclastos/efectos de los fármacos , Células RAW 264.7 , Ligando RANK/metabolismo , Ligando RANK/efectos de los fármacos , Femenino , Estructura Molecular , Ovariectomía , Osteoprotegerina
9.
Acta Radiol ; 65(7): 744-752, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38870345

RESUMEN

BACKGROUND: Preoperative effective assessment of cervical lymph node metastasis in thyroid cancer plays an important role in formulating the surgical plan. PURPOSE: To investigate the significance of synthetic magnetic resonance imaging (MRI) for quantitatively analyzing cervical lymph node metastasis in thyroid cancer. MATERIAL AND METHODS: A retrospective analysis was conducted on 30 patients with thyroid cancer, consisting of 19 thyroid cancer nodules, 45 metastatic lymph nodes, and 47 non-metastatic lymph nodes. Regions of interest (ROIs) for each type of nodule were manually delineated using a workstation. Quantitative parameters, such as T1, T2, and proton density (PD) values, were automatically extracted from synthetic MRI scans. Statistical tests and regression analysis were performed to assess differences and correlations among the quantitative parameters. RESULTS: There were no significant differences in the quantitative parameter values between the primary tumor and metastatic lymph node tissues (P > 0.05). However, significant differences were observed in the quantitative parameters between the primary tumor and non-metastatic lymph node tissues and between the metastatic and non-metastatic lymph node tissues (P < 0.05). The diagnostic accuracy for cervical lymph node metastasis in thyroid cancer was 94.4% for the T1 and T2 combined index, 91.9% for T2, 86.8% for T1, and 71.7% for PD values. CONCLUSION: The application of quantitative parameters from synthetic MRI can assist clinicians in accurately planning surgical interventions for thyroid cancer patients before surgery.


Asunto(s)
Ganglios Linfáticos , Metástasis Linfática , Imagen por Resonancia Magnética , Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Metástasis Linfática/diagnóstico por imagen , Femenino , Masculino , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Adulto , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Anciano , Cuello/diagnóstico por imagen , Cuello/patología , Reproducibilidad de los Resultados
10.
Mar Drugs ; 22(3)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38535476

RESUMEN

With the emergence of drug-resistant strains, the treatment of tuberculosis (TB) is becoming more difficult and there is an urgent need to find new anti-TB drugs. Mycobacterium marinum, as a model organism of Mycobacterium tuberculosis, can be used for the rapid and efficient screening of bioactive compounds. The 14-membered resorcylic acid lactones (RALs) have a wide range of bioactivities such as antibacterial, antifouling and antimalarial activity. In order to further study their bioactivities, we initially constructed a 14-membered RALs library, which contains 16 new derivatives. The anti-M. marinum activity was evaluated in vitro. Derivatives 12, 19, 20 and 22 exhibited promising activity with MIC90 values of 80, 90, 80 and 80 µM, respectively. The preliminary structure-activity relationships showed that the presence of a chlorine atom at C-5 was a key factor to improve activity. Further studies showed that 12 markedly inhibited the survival of M. marinum and significantly reduced the dosage of positive drugs isoniazid and rifampicin when combined with them. These results suggest that 12 is a bioactive compound capable of enhancing the potency of existing positive drugs, and its effective properties make it a very useful leads for future drug development in combating TB resistance.


Asunto(s)
Antimaláricos , Mycobacterium marinum , Anticuerpos , Antituberculosos , Lactonas
11.
Phytochem Anal ; 35(4): 860-872, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38361458

RESUMEN

INTRODUCTION: Liuweizhiji Gegen-Sangshen (LGS) oral liquid is a Chinese patent medicine that is widely used for the prevention and treatment of alcoholic liver disease in clinical practice. However, the chemical complexity of LGS has not yet been investigated. OBJECTIVE: The aim of this study was to rapidly identify chemical constituents of LGS and establish a quality control method based on fingerprint and quantitative analysis. METHODOLOGY: A comprehensive strategy was used by combining qualitative analysis by ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and fingerprint analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD). RESULTS: A total of 162 chemical components in LGS, including 91 flavonoids, 31 organic acids, and 20 phenolic compounds, were identified or preliminarily characterized in both positive and negative ion modes based on the UPLC-Q-TOF-MS results. Of these, 37 were confirmed with the reference standards. In fingerprint analysis, 23 peaks were chosen as common peaks and used to evaluate the similarity of different batches of LGS. Subsequently, a rapid quantification method was optimized and validated for the simultaneous determination of multiple chemical markers in LGS. The validated quantitative method was successfully used to analyze different batches of LGS samples. CONCLUSION: The proposed comprehensive strategy combining HPLC-DAD fingerprinting and multi-component quantification demonstrated satisfactory results with high efficiency, accuracy, and reliability. This can be used as a reference for the overall quality consistency evaluation of Chinese patent medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Control de Calidad , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Flavonoides/análisis , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Administración Oral , Fenoles/análisis
12.
J Wound Care ; 33(4): 262-270, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38573899

RESUMEN

OBJECTIVE: This study examined changes in wound symptoms and the health-related quality of life (HRQoL) of patients with newly diagnosed malignant fungating wounds, and explored the factors that impacted the changes in HRQoL. METHOD: This prospective longitudinal study included patients from three hospitals in China who had been diagnosed with malignant fungating wounds. Questionnaires were used to assess patients' HRQoL and their wound symptoms at the time of diagnosis (T0), as well as at one, three and six (T1, T2 and T3, respectively) months following the treatment period. Factors related to changes in HRQoL were analysed using generalised estimating equation models. RESULTS: A total of 162 patients were included in the study. The patients reported low overall HRQoL. In three health-related dimensions (functional status, social relations and mental health), patients reported lower functional status at the time of wound diagnosis (T0), which then increased slowly with treatment over time. A lower QoL was associated with odour, exudate, bleeding, pruritus, a low performance status and the need for the dressing of wounds. CONCLUSION: The HRQoL of patients with malignant fungating wounds exhibited significant changes across different periods. It is thus of great importance to formulate pragmatic, patient and family-centred palliative wound care management strategies.


Asunto(s)
Calidad de Vida , Heridas y Lesiones , Humanos , Estudios Prospectivos , Estudios Longitudinales , Vendajes , Hemorragia , Heridas y Lesiones/terapia
13.
Plant Foods Hum Nutr ; 79(1): 73-82, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38006459

RESUMEN

Fruits of Syzygium jambos (L.) are recognized as a "food", exhibiting significant antidiabetic activities. However, the α-glucosidase inhibition of the components from Syzygium jambos (L.) have not yet been investigated. In this study, a total of 14 compounds were isolated from Syzygium jambos (L.) Alston, eight of which showed significant inhibitory effects on α-glucosidase, with IC50 values in the range of 0.011-0.665 mM. Notably, compounds 1-3 (IC50: 0.013, 0.011 and 0.030 mM, respectively) exhibited much stronger activity than acarbose (IC50: 2.329 ± 0.109 mM). The enzyme kinetics study indicated that compound 1 was an uncompetitive inhibitor, and compounds 2-8 were mixed-type inhibitors. Moreover, the interactions between compounds and α-glucosidase were investigated by molecular docking, which further revealed that the number of olefin double bonds and 2-COOH of heptadeca-phenols had a notable effect on the α-glucosidase inhibitory activity. This study demonstrated that Syzygium jambos (L.) fruit might serve as a functional food for the prevention of diabetes mellitus.


Asunto(s)
Syzygium , Syzygium/química , Simulación del Acoplamiento Molecular , alfa-Glucosidasas/metabolismo , Inhibidores Enzimáticos , Análisis Espectral , Inhibidores de Glicósido Hidrolasas/farmacología , Cinética
14.
Angew Chem Int Ed Engl ; : e202411150, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136333

RESUMEN

The first wide-view image of multiple structural and phase transformations for MOFs from crystal state transformations further to the extreme limit approaching liquid/glass phase, was presented based on a square-layer framework of [Co2(pybz)2(CH3COO)2]·DMF (Co2). The process involves i) an initial crystalline transformation brings to a 3-fold interpenetrated and ordered vacancies contained framework [Co(pybz)2(CH3OH)2]·2CH3OH (CoM) due to in-situ disassemble-reassemble, ii) thermal induced departure of a pair of cis-form coordinated methanol in CoM leads to amorphous framework (a-dCoM), iii) glass transition (Tg = 566 K) to super-cooled liquid (scl-dCoM, spanning 38 K), iv) obtaining MOF glass g-dCoM upon quenching the super-cooled liquid, and v) re-crystallization of super-cooled liquid to six-fold interpenetrated dia-net framework [Co(pybz)2]6n (rec-dCoM) under heating above 604 K. The access to glass from CoM, provides a new self-perturbation strategy to create more MOF glasses without melting. The wider pore size distribution in amorphous/glassy MOFs than crystalline precursor realized the first time selective hydrocarbon gas separation by breakthrough experiments, which bring efficient separation of 1:99 C2H2/C2H4 by either a-dCoM or g-dCoM and produce polymer grade C2H4 with purity ≥ 99.5% after a single adsorption process. Furthermore, the mixture of 50:50 C3H6/C3H8 can be separated by a-dCoM.

15.
Genes Immun ; 24(4): 159-170, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37422588

RESUMEN

The current diagnostic biomarkers of acute myocardial infarction (AMI), troponins, lack specificity and exist as false positives in other non-cardiac diseases. Previous studies revealed that cuproptosis, ferroptosis, and immune infiltration are all involved in the development of AMI. We hypothesize that combining the analysis of cuproptosis, ferroptosis, and immune infiltration in AMI will help identify more precise diagnostic biomarkers. The results showed that a total of 19 cuproptosis- and ferroptosis-related genes (CFRGs) were differentially expressed between the healthy and AMI groups. Functional enrichment analysis showed that the differential CFRGs were mostly enriched in biological processes related to oxidative stress and the inflammatory response. The immune infiltration status analyzed by ssGSEA found elevated levels of macrophages, neutrophils, and CCR in AMI. Then, we screened 6 immune-related CFRGs (CXCL2, DDIT3, DUSP1, CDKN1A, TLR4, STAT3) to construct a nomogram for predicting AMI and validated it in the GSE109048 dataset. Moreover, we also identified 5 pivotal miRNAs and 10 candidate drugs that target the 6 feature genes. Finally, RT-qPCR analysis verified that all 6 feature genes were upregulated in both animals and patients. In conclusion, our study reveals the significance of immune-related CFRGs in AMI and provides new insights for AMI diagnosis and treatment.


Asunto(s)
Apoptosis , Ferroptosis , Infarto del Miocardio , Animales , Biomarcadores , Ferroptosis/genética , Genes cdc , Macrófagos , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/genética , Cobre
16.
Small ; 19(5): e2206724, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36436832

RESUMEN

The discovery and in-depth study of non-biocatalytic applications of active biomolecules are essential for the development of biomimicry. Here, the effect of intermolecular hydrogen-bonding traction on the CO2 photoactivation performance of adenine nucleobase by means of an adenine-containing model system (AMOF-1-4) is uncovered. Remarkably, the hydrogen-bonding schemes around adenines are regularly altered with the increase in the alkyl (methyl, ethyl, isopropyl, and tert-butyl) electron-donating capacity of the coordinated aliphatic carboxylic acids, and thus, lead to a stepwise improvement in CO2 photoreduction activity. Density functional theory calculations demonstrate that strong intermolecular hydrogen-bonding traction surrounding adenine can obviously increase the adenine-CO2 interaction energy and, therefore, result in a smoother CO2 activation process. Significantly, this work also provides new inspiration for expanding the application of adenine to more small-molecule catalytic reactions.


Asunto(s)
Adenina , Dióxido de Carbono , Tracción , Enlace de Hidrógeno , Catálisis
17.
Opt Express ; 31(24): 39424-39432, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38041264

RESUMEN

The non-Hermitian skin effect (NHSE) on the non-Hermitian Haldane model with gain and loss on the honeycomb lattice with the outline of a triangle is discussed. The NHSE only occurs on the edge of the lattice, transforming the edge modes into the higher-order corner modes. The NHSE can also occur on a lattice with only loss, which can be treated as a lattice with gain and loss as well as a global loss added to it. When the saturated gain is added to the three corner sites of the dissipative lattice, a single-mode laser system is obtained. When any one site is stimulated initially, the system will reach a saturated state depending on the distribution of the corner modes, and the stable laser light is emitted by sites at the corners.

18.
Opt Express ; 31(3): 3427-3440, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36785336

RESUMEN

A nonlinear non-Hermitian topological laser system based on the higher-order corner states of the 2-dimensional (2D) Su-Schrieffer-Heeger (SSH) model is investigated. The topological property of this nonlinear non-Hermitian system described by the quench dynamics is in accordance with that of a normal 2D SSH model. In the topological phase, all sites belonging to the topological corner states begin to emit stable laser light when a pulse is given to any one site of the lattice, while no laser light is emitted when the lattice is in the trivial phase. Furthermore, the next-nearest-neighbor (NNN) couplings are introduced into the strong-coupling unit cells of the 2D SSH model, which open a band gap in the continuous band structure. In the topological phase, similar to the case of 2D SSH model without NNN couplings, the corner sites can emit stable laser light due to the robustness of the higher-order corner states when the NNN couplings are regarded as the perturbation. However, amplitude of the stimulated site does not decay to zero in the trivial phase, because the existence of the NNN couplings in the strong-coupling unit cells make the lattice like one in the tetramer limit, and a weaker laser light is emitted by each corner.

19.
Opt Express ; 31(10): 15342-15354, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157638

RESUMEN

We explore the influence of the artificial atomic chain on the input-output relation of the cavity. Specifically, we extend the atom chain to the one-dimensional Su-Schrieffer-Heeger (SSH) chain to check the role of atomic topological non-trivial edge state on the transmission characteristics of the cavity. The superconducting circuits can realize the artificial atomic chain. Our results show that the atom chain is not equivalent to atom gas, and the transmission properties of the cavity containing the atom chain are entirely different from that of the cavity containing atom gas. When the atom chain is arranged in the form of topological non-trivial SSH model, the atom chain can be equivalent to the three-level atom, in which the edge state contributes to the second level and is resonant with the cavity, while the high-energy bulk state contributes to form the third level and is greatly detuned with the cavity. Therefore, the transmission spectrum shows no more than three peaks. This allows us to infer the topological phase of the atomic chain and the coupling strength between the atom and the cavity only from the profile of the transmission spectrum. Our work is helping to understand the role of topology in quantum optics.

20.
J Natl Compr Canc Netw ; 21(6): 594-608, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37308117

RESUMEN

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Breast Cancer address all aspects of management for breast cancer. The treatment landscape of metastatic breast cancer is evolving constantly. The therapeutic strategy takes into consideration tumor biology, biomarkers, and other clinical factors. Due to the growing number of treatment options, if one option fails, there is usually another line of therapy available, providing meaningful improvements in survival. This NCCN Guidelines Insights report focuses on recent updates specific to systemic therapy recommendations for patients with stage IV (M1) disease.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Oncología Médica
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