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1.
Sci Adv ; 9(44): eadi8500, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37910611

RESUMEN

The topological phase revolutionized wave transport, enabling integrated photonic interconnects with sharp light bending on a chip. However, the persistent challenge of momentum mismatch during intermedium topological mode transitions due to material impedance inconsistency remains. We present a 100-Gbps topological wireless communication link using integrated photonic devices that conserve valley momentum. The valley-conserved silicon topological waveguide antenna achieves a 12.2-dBi gain, constant group delay across a 30-GHz bandwidth and enables active beam steering within a 36° angular range. The complementary metal oxide semiconductor-compatible valley-conserved devices represent a major milestone in hybrid electronic-photonic-based topological wireless communications, enabling terabit-per-second backhaul communication, high throughput, and intermedium transport of information carriers, vital for the future of communication from the sixth to X generation.

2.
Nat Commun ; 13(1): 5404, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109511

RESUMEN

The revolutionary 5G cellular systems represent a breakthrough in the communication network design to provide a single platform for enabling enhanced broadband communications, virtual reality, autonomous driving, and the internet of everything. However, the ongoing massive deployment of 5G networks has unveiled inherent limitations that have stimulated the demand for innovative technologies with a vision toward 6G communications. Terahertz (0.1-10 THz) technology has been identified as a critical enabler for 6G communications with the prospect of massive capacity and connectivity. Nonetheless, existing terahertz on-chip communication devices suffer from crosstalk, scattering losses, limited data speed, and insufficient tunability. Here, we demonstrate a new class of phototunable, on-chip topological terahertz devices consisting of a broadband single-channel 160 Gbit/s communication link and a silicon Valley Photonic Crystal based demultiplexer. The optically controllable demultiplexing of two different carriers modulated signals without crosstalk is enabled by the topological protection and a critically coupled high-quality (Q) cavity. As a proof of concept, we demultiplexed high spectral efficiency 40 Gbit/s signals and demonstrated real-time streaming of uncompressed high-definition (HD) video (1.5 Gbit/s) using the topological photonic chip. Phototunable silicon topological photonics will augment complementary metal oxide semiconductor (CMOS) compatible terahertz technologies, vital for accelerating the development of futuristic 6G and 7G communication era driving the real-time terabits per second wireless connectivity for network sensing, holographic communication, and cognitive internet of everything.

3.
Adv Mater ; 34(27): e2202370, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35419880

RESUMEN

Rapid scaling of semiconductor devices has led to an increase in the number of processor cores and integrated functionalities onto a single chip to support the growing demands of high-speed and large-volume consumer electronics. To meet this burgeoning demand, an improved interconnect capacity in terms of bandwidth density and active tunability is required for enhanced throughput and energy efficiency. Low-loss terahertz silicon interconnects with larger bandwidth offer a solution for the existing inter-/intrachip bandwidth density and energy-efficiency bottleneck. Here, a low-loss terahertz topological interconnect-cavity system is presented that can actively route signals through sharp bends, by critically coupling to a topological cavity with an ultrahigh-quality (Q) factor of 0.2 × 106 . The topologically protected large Q factor cavity enables energy-efficient optical control showing 60 dB modulation. Dynamic control is further demonstrated of the critical coupling between the topological interconnect-cavity for on-chip active tailoring of the cavity resonance linewidth, frequency, and modulation through complete suppression of the back reflection. The silicon topological cavity is complementary metal-oxide-semiconductor (CMOS)-compatible and highly desirable for hybrid electronic-photonic technologies for sixth (6G) generation terahertz communication devices. Ultrahigh-Q cavity also paves the path for designing ultrasensitive topological sensors, terahertz topological integrated circuits, and nonlinear topological photonic devices.

4.
J Dig Dis ; 17(6): 392-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27107396

RESUMEN

OBJECTIVE: Cyanoacrylate (CYA) injection is recommended for bleeding gastric varices (GV) but with significant adverse effects. Transesophageal endoscopic ultrasound-guided therapy of large GV with a combined coil and CYA injection has shown promising results. However, it is expensive and requires technical expertise. In this study, we aimed to compare the safety and efficacy of a new method with UCYA [undiluated CYA (UCYA) followed by lipiodol-diluated CYA (DCYA)] in the management of large bleeding GV. METHODS: Fifteen consecutive patients with bleeding from large GV (>1 cm) were prospectively treated with DCYA and another 15 patients treated with UCYA retrospectively. All patients in the DCYA group underwent thoracic computed tomography scan to identify glue embolism. RESULTS: Baseline characteristics were similar between the two groups. Rates of GV obliteration and rebleeding were 100% vs 93.3% (P = 0.309) and 6.7% vs 33.3% (P = 0.06) in the DCYA and UCYA groups, respectively. One patient in the UCYA group had needle fixation which led to fatal bleeding after forceful needle extraction. In DCYA group none had glue embolism. CONCLUSIONS: Both UCYA and DCYA are effective in treating bleeding from large GV. DCYA has lower rebleeding rates and tends to have fewer adverse events than UCYA injection, although the differences are not statistically significant. Large-sample-sized prospective randomized trials are required.


Asunto(s)
Cianoacrilatos/uso terapéutico , Várices Esofágicas y Gástricas/tratamiento farmacológico , Hemorragia Gastrointestinal/tratamiento farmacológico , Adhesivos Tisulares/uso terapéutico , Adulto , Cianoacrilatos/administración & dosificación , Cianoacrilatos/efectos adversos , Esofagoscopía/métodos , Aceite Etiodizado , Femenino , Gastroscopía/métodos , Hemostasis Endoscópica/métodos , Humanos , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Estudios Retrospectivos , Escleroterapia/efectos adversos , Escleroterapia/métodos , Adhesivos Tisulares/administración & dosificación , Adhesivos Tisulares/efectos adversos , Tomografía Computarizada por Rayos X
5.
Life Sci ; 151: 330-338, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26979773

RESUMEN

AIM AND MAIN METHOD: The medicinal properties of fermented papaya preparation (FPP) derived from Carica papaya fruit was investigated in order to determine its ability to modulate the progression of N-methyl-N-nitrosourea induced hepatocellular carcinoma in Balb/c mice. KEY FINDINGS: As well as reducing the physical symptoms associated with N-methyl-N-nitrosourea (MNU)-induced hepatocellular carcinoma, supplementation of Balb/c mice with 500mg FPP/kg BW for 92days normalized the blood cell count, led to an increased activity of several key antioxidant enzymes (SOD: +20%, CAT: +81%, GPx: +66.1%, GR: +54.4%; P<0.001 vs. MNU control), increased the ferrous reducing antioxidant potential (+36.7%, P<0.001 vs. MNU control) and reduced the extent of lipid peroxidation in the liver by 44.3% (P<0.001 vs. MNU control). SIGNIFICANCE: Results demonstrated the ability of FPP to preserve the integrity of liver against oxidative damage and protect hepatocytes against irreversible DNA structural modifications induced by MNU, highlighting its potential role as an immune-defense modulator during hepatocarcinoma.


Asunto(s)
Carica/química , Progresión de la Enfermedad , Fermentación , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Metilnitrosourea , Preparaciones de Plantas/farmacología , Preparaciones de Plantas/uso terapéutico , Animales , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Recuento de Células Sanguíneas , Frutas , Hemoglobinas/metabolismo , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/prevención & control , Masculino , Ratones , Ratones Endogámicos BALB C , Preparaciones de Plantas/química
6.
Food Funct ; 7(1): 594-609, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26574664

RESUMEN

The hepatoprotective potential of edible mushrooms from Mauritius, namely Pleurotus sajor-caju and Agaricus bisporus was evaluated using an N-methyl-N-nitrosourea (MNU)-induced hepatocarcinogenesis Balb/c mice model. Mushroom extracts restored normal weight in MNU treated mice over a 3 month supplementation period. Blood parameter analyses indicated a clear modulation of hemoglobin concentration, leukocyte, platelet, lymphocyte, neutrophil, monocyte and eosinophil counts in MNU-induced mice (p < 0.05). Mushroom extract supplementation effectively reduced oxidative damage in MNU-primed mice, which was marked by a significant decrease in the extent of lipid peroxidation (p < 0.05) and a concomitant increase in the enzymatic antioxidant levels, primarily catalase, superoxide dismutase, glutathione reductase and peroxidase, and FRAP values (p < 0.05). DNA protective effects of the extracts were confirmed by Raman spectroscopy, where, the MNU-DNA interaction, as evidenced by an intense peak at 1254 cm(-1), was normalized. The findings demonstrate hepatoprotective, immunomodulatory and anti-carcinogenic effects and suggest the use of mushrooms as potential dietary prophylactics in cancer chemoprevention.


Asunto(s)
Agaricales/química , Antineoplásicos/uso terapéutico , Carcinogénesis/inducido químicamente , Neoplasias Hepáticas/inducido químicamente , Metilnitrosourea/toxicidad , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria
7.
Pharm Biol ; 51(10): 1272-81, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23855803

RESUMEN

CONTEXT AND OBJECTIVE: Tobacco smoke and nitrostable foods containing N-methyl N-nitrosourea (MNU) are among the primary causes of liver cancer. To substantiate the beneficial claims ascribed to Aegle marmelos (L.) Corrêa (Rutaceae), the hepatoprotective potential of its leaf extract was studied using an MNU-induced hepatocarcinogenesis model in Balb/c mice. MATERIALS AND METHODS: After dose selection, 40 mice were randomly assigned to 4 groups: I (control), II (intraperitoneally (i.p.) primed with 50 mg/kg MNU), III (100 mg/kg A. marmelos hydroalcoholic extract (HEAM) i.p.) and IV (MNU + HEAM, i.p.). Inflammatory (IL-1ß, IL-6), anti-inflammatory (IL-4) cytokine expression, apoptosis (Bcl-2) and tumor-related (p53, c-jun) genes were assessed at mRNA level. HEAM effects on hematological parameters were examined. RESULTS AND DISCUSSION: HEAM treatment decreased IL-1ß, IL-6, Bcl-2 and c-jun respectively expressions by 90, 25, 53 and 30%, respectively. p53 and IL-4 expression was up-regulated by 1.5- and 2-fold. MNU decreased hemoglobin concentration (25%), lymphocyte count (42%) and increased leukocyte (100%), platelet (4-fold), neutrophil (43%), monocyte (10-fold) and eosinophil (10-fold) counts in Group II mice while HEAM modulated the same parameters by -7%, -21%, +24%, +3-fold, +12%, +3-fold and +4-fold, respectively, in MNU-induced mice compared to control. HEAM protective effect was confirmed by Raman spectroscopy where the MNU-induced peak at 1252 cm(-1) was normalized. DNA fragmentation data suggest apoptosis as one of the protective mechanisms of HEAM. CONCLUSION: The hepatoprotective, anti-carcinogenic and immunomodulatory effects of A. marmelos extract indicate potential beneficial effects in cancer therapy.


Asunto(s)
Anticarcinógenos/farmacología , Factores Inmunológicos/farmacología , Neoplasias Hepáticas Experimentales/prevención & control , Metilnitrosourea , Extractos Vegetales/farmacología , Aegle/química , Animales , Anticarcinógenos/administración & dosificación , Anticarcinógenos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/aislamiento & purificación , Mediadores de Inflamación/metabolismo , Inyecciones Intraperitoneales , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta , Plantas Medicinales , Factores de Tiempo
8.
J Vector Borne Dis ; 42(1): 36-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15999460

RESUMEN

BACKGROUND & OBJECTIVE: The effect of aqueous extract of Tinospora cordifolia, an immunomodulator with antimalarial activity along with chloroquine was studied in the treatment of three cases of hyper-reactive malarious splenomegaly in District Hospital, Daltonganj town, Jharkhand, India. These cases were partial/slow responders to the conventional antimalarial drug chloroquine. METHODS: Aqueous extract of T. cordifolia (500 mg) was added to chloroquine (CQ) base (300 mg) weekly and CQ prophylaxis was observed up to six months. Improvement was gauzed by measuring spleen enlargement, Hb, serum IgM and well-being in three cases of hyper-reactive malarious splenomegaly. RESULTS: Addition of extract of T. cordifolia for the first six weeks to chloroquine showed regression of spleen by 37-50% after six weeks and 45-69% after six months from the start of treatment. Likewise decrease in IgM and increase in Hb as well as wellbeing (Karnofsky performance scale) were observed. CONCLUSION: The results of the present study paves a new sight in the treatment of hyper-reactive malarious splenomegaly, however, large-scale trial is required to confirm the beneficial effect of T. cordifolia extract in combination with chloroquine.


Asunto(s)
Malaria Vivax/complicaciones , Medicina Ayurvédica , Fitoterapia , Extractos Vegetales/uso terapéutico , Esplenomegalia/tratamiento farmacológico , Esplenomegalia/etiología , Tinospora/química , Adulto , Quimioterapia Adyuvante/métodos , Cloroquina/uso terapéutico , Quimioterapia Combinada , Femenino , Hemoglobinas , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Bazo/patología , Esplenomegalia/patología
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