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1.
Mol Cell ; 72(6): 985-998.e7, 2018 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-30415949

RESUMEN

Current models of SIRT1 enzymatic regulation primarily consider the effects of fluctuating levels of its co-substrate NAD+, which binds to the stably folded catalytic domain. By contrast, the roles of the sizeable disordered N- and C-terminal regions of SIRT1 are largely unexplored. Here we identify an insulin-responsive sensor in the SIRT1 N-terminal region (NTR), comprising an acidic cluster (AC) and a 3-helix bundle (3HB), controlling deacetylase activity. The allosteric assistor DBC1 removes a distal N-terminal shield from the 3-helix bundle, permitting PACS-2 to engage the acidic cluster and the transiently exposed helix 3 of the 3-helix bundle, disrupting its structure and inhibiting catalysis. The SIRT1 activator (STAC) SRT1720 binds and stabilizes the 3-helix bundle, protecting SIRT1 from inhibition by PACS-2. Identification of the SIRT1 insulin-responsive sensor and its engagement by the DBC1 and PACS-2 regulatory hub provides important insight into the roles of disordered regions in enzyme regulation and the mode by which STACs promote metabolic fitness.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Hepatocitos/enzimología , Insulina/metabolismo , Sirtuina 1/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Regulación Alostérica , Animales , Sitios de Unión , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Células HCT116 , Hepatocitos/efectos de los fármacos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos , Resistencia a la Insulina , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/enzimología , Obesidad/genética , Obesidad/prevención & control , Unión Proteica , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Estabilidad Proteica , Sirtuina 1/genética , Proteínas de Transporte Vesicular/deficiencia , Proteínas de Transporte Vesicular/genética
2.
Am J Pathol ; 194(6): 1047-1061, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38403161

RESUMEN

Hyaluronan (HA), a negatively charged linear glycosaminoglycan, is a key macromolecular component of the articular cartilage extracellular matrix. The differential effects of HA are determined by a spatially/temporally regulated display of HA receptors, such as CD44 and receptor for hyaluronan-mediated motility (RHAMM). HA signaling through CD44 with RHAMM has been shown to stimulate inflammation and fibrotic processes. This study shows an increased expression of RHAMM in proinflammatory macrophages. Interfering with HA/RHAMM interactions using a 15-mer RHAMM-mimetic, HA-binding peptide, together with high-molecular-weight (HMW) HA reduced the expression and release of inflammatory markers and increased the expression of anti-inflammatory markers in proinflammatory macrophages. HA/RHAMM interactions were interfered in vivo during the regeneration of a full-thickness cartilage defect after microfracture surgery in rabbits using three intra-articular injections of 15-mer RHAMM-mimetic. HA-binding peptide together with HMWHA reduced the number of proinflammatory macrophages and increased the number of anti-inflammatory macrophages in the injured knee joint and greatly improved the repair of the cartilage defect compared with intra-articular injections of HMWHA alone. These findings suggest that HA/RHAMM interactions play a key role in cartilage repair/regeneration via stimulating inflammatory and fibrotic events, including increasing the ratio of proinflammatory/anti-inflammatory macrophages. Interfering with these interactions reduced inflammation and greatly improved cartilage repair.


Asunto(s)
Cartílago Articular , Receptores de Hialuranos , Ácido Hialurónico , Macrófagos , Animales , Receptores de Hialuranos/metabolismo , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Conejos , Cartílago Articular/metabolismo , Cartílago Articular/patología , Ácido Hialurónico/metabolismo , Ácido Hialurónico/farmacología , Proteínas de la Matriz Extracelular/metabolismo , Polaridad Celular/efectos de los fármacos , Polaridad Celular/fisiología , Regeneración/efectos de los fármacos , Regeneración/fisiología , Inflamación/metabolismo , Inflamación/patología
3.
Proc Natl Acad Sci U S A ; 119(22): e2121406119, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35622890

RESUMEN

In eukaryotes, the origin recognition complex (ORC) is required for the initiation of DNA replication. The smallest subunit of ORC, Orc6, is essential for prereplication complex (pre-RC) assembly and cell viability in yeast and for cytokinesis in metazoans. However, unlike other ORC components, the role of human Orc6 in replication remains to be resolved. Here, we identify an unexpected role for hOrc6, which is to promote S-phase progression after pre-RC assembly and DNA damage response. Orc6 localizes at the replication fork and is an accessory factor of the mismatch repair (MMR) complex. In response to oxidative damage during S phase, often repaired by MMR, Orc6 facilitates MMR complex assembly and activity, without which the checkpoint signaling is abrogated. Mechanistically, Orc6 directly binds to MutSα and enhances the chromatin-association of MutLα, thus enabling efficient MMR. Based on this, we conclude that hOrc6 plays a fundamental role in genome surveillance during S phase.


Asunto(s)
Reparación de la Incompatibilidad de ADN , Complejo de Reconocimiento del Origen , Fase S , Proteínas de Unión al ADN/metabolismo , Humanos , Proteínas MutL/metabolismo , Complejo de Reconocimiento del Origen/genética , Complejo de Reconocimiento del Origen/metabolismo , Unión Proteica
4.
Ann Surg Oncol ; 31(4): 2349-2356, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38308160

RESUMEN

BACKGROUND: The recurrence of thyroid cancer poses challenges compounded by postoperative fibrosis and anatomic changes. By overcoming the limitations of current localizing dye techniques, indocyanine green-macroaggregated albumin-hyaluronic acid (ICG-MAA-HA) mixture dye promises improved localization. This study aimed to evaluate the efficacy and safety of the dye for recurrent thyroid cancer. METHODS: The nine patients in this study underwent surgery and postoperative ultrasonography. The dye was injected into recurrent lesions in all the patients preoperatively. During surgery, the lesions were confirmed with an imaging system before and after excision. If the lesion was unidentifiable with the naked eye, surgical excision was performed under the corresponding fluorescent guide. Side effects related to the dye injection and completeness of the surgery were evaluated. RESULTS: No side effects such as bleeding, skin tattooing, or pain during or after the dye injection were reported, and no discoloration occurred that interfered with the surgical field of view during surgery. In three cases (33.3 %), because it was difficult to localize metastatic lesions with the naked eye, the operation was successfully completed using an imaging system. The completeness of the surgical resection was confirmed by ultrasonography after an average of 5 months postoperatively. CONCLUSION: The study found that ICG-MAA-HA dye effectively located metastatic and recurrent thyroid cancer and had favorable results in terms of minimal procedural side effects and potential for assisting the surgeon. A large-scale multi-institutional study is necessary to prove the clinical significance regarding patient survival and disease control.


Asunto(s)
Verde de Indocianina , Neoplasias de la Tiroides , Humanos , Ácido Hialurónico , Colorantes , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Albúminas , Biopsia del Ganglio Linfático Centinela/métodos
5.
Nanotechnology ; 35(27)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38522102

RESUMEN

To obtain high-quality SiNxfilms applicable to an extensive range of processes, such as gate spacers in fin field-effect transistors (FinFETs), the self-aligned quadruple patterning process, etc, a study of plasma with higher plasma density and lower plasma damage is crucial in addition to study on novel precursors for SiNxplasma-enhanced atomic layer deposition (PEALD) processes. In this study, a novel magnetized PEALD process was developed for depositing high-quality SiNxfilms using di(isopropylamino)silane (DIPAS) and magnetized N2plasma at a low substrate temperature of 200 °C. The properties of the deposited SiNxfilms were analyzed and compared with those obtained by the PEALD process using a non-magnetized N2plasma source under the same conditions. The PEALD SiNxfilm, produced using an external magnetic field (ranging from 0 to 100 G) during the plasma exposure step, exhibited a higher growth rate (∼1 Å/cycle) due to the increased plasma density. Additionally, it showed lower surface roughness, higher film density, and enhanced wet etch resistance compared to films deposited using the PEALD process with non-magnetized plasmas. This improvement can be attributed to the higher ion flux and lower ion energy of the magnetized plasma. The electrical characteristics, such as interface trap density and breakdown voltage, were also enhanced when the magnetized plasma was used for the PEALD process. Furthermore, when SiNxfilms were deposited on high-aspect-ratio (30:1) trench patterns using the magnetized PEALD process, an improved step coverage of over 98% was achieved, in contrast to the conformality of SiNxdeposited using non-magnetized plasma. This enhancement is possibly a result of deeper radical penetration enabled by the magnetized plasma.

6.
Nucleic Acids Res ; 50(16): 9175-9189, 2022 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-35950495

RESUMEN

Stress-responsive genes are lowly transcribed under normal conditions and robustly induced in response to stress. The significant difference between basal and induced transcription indicates that the general transcriptional machinery requires a mechanism to distinguish each transcription state. However, what factors specifically function in basal transcription remains poorly understood. Using a classic model stress-responsive gene (Drosophila MtnA), we found that knockdown of the DEAD-box helicase Hlc resulted in a significant transcription attenuation of MtnA under normal, but not stressed, conditions. Mechanistically, Hlc directly binds to the MtnA locus to maintain the accessibility of chromatin near the transcriptional start site, which allows the recruitment of RNA polymerase II and subsequent MtnA transcription. Using RNA-seq, we then identified plenty of additional stress-responsive genes whose basal transcription was reduced upon knockdown of Hlc. Taken together, these data suggest that Hlc-mediated basal transcription regulation is an essential and widespread mechanism for precise control of stress-responsive genes.


Asunto(s)
Cromatina , ARN Polimerasa II , Animales , Cromatina/genética , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , ADN Helicasas/genética , ADN Helicasas/metabolismo , Regulación de la Expresión Génica , Drosophila/genética , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo
7.
Mar Drugs ; 22(3)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38535450

RESUMEN

A biocompatible, heterogeneous, fucose-rich, sulfated polysaccharide (fucoidan) is biosynthesized in brown seaweed. In this study, fucoidan was isolated from Padina arborescens (PAC) using celluclast-assisted extraction, purified, and evaluated for its anti-inflammatory potential in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Structural analyses were performed using Fourier transform infrared (FTIR) and scanning electron microscopy. Among the purified fucoidans, fucoidan fraction 5 (F5) exhibited strong inhibitory activity against LPS-induced nitric oxide (NO) production and pro-inflammatory cytokine generation through the regulation of iNOS/COX-2, MAPK, and NF-κB signaling in LPS-induced RAW 264.7 cells. Determination of the structural characteristics indicated that purified F5 exhibited characteristics similar to those of commercial fucoidan. In addition, further analyses suggested that F5 inhibits LPS-induced toxicity, cell death, and NO generation in zebrafish models. Taken together, these findings imply that P. arborescens fucoidans have exceptional anti-inflammatory action, both in vitro and in vivo, and that they may have prospective uses in the functional food sector.


Asunto(s)
Lipopolisacáridos , Phaeophyceae , Animales , Pez Cebra , Polisacáridos , Inflamación , Óxido Nítrico
8.
Mar Drugs ; 22(3)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38535454

RESUMEN

Muscle atrophy is a detrimental and injurious condition that leads to reduced skeletal muscle mass and disruption of protein metabolism. Oyster (Crassostrea nippona) is a famous and commonly consumed shellfish in East Asia and has become a popular dietary choice worldwide. The current investigation evaluated the efficacy of C. nippona against muscle atrophy, which has become a severe health issue. Mammalian skeletal muscles are primarily responsible for efficient metabolism, energy consumption, and body movements. The proteins that regulate muscle hypertrophy and atrophy are involved in muscle growth. C. nippona extracts were enzymatically hydrolyzed using alcalase (AOH), flavourzyme (FOH), and protamex (POH) to evaluate their efficacy in mitigating dexamethasone-induced muscle damage in C2C12 cells in vitro. AOH exhibited notable cell proliferative abilities, promoting dose-dependent myotube formation. These results were further solidified by protein expression analysis. Western blot and gene expression analysis via RT-qPCR demonstrated that AOH downregulated MuRF-1, Atrogin, Smad 2/3, and Foxo-3a, while upregulating myogenin, MyoD, myosin heavy chain expression, and mTOR, key components of the ubiquitin-proteasome and mTOR signaling pathways. Finally, this study suggests that AOH holds promise for alleviating dexamethasone-induced muscle atrophy in C2C12 cells in vitro, offering insights for developing functional foods targeting conditions akin to sarcopenia.


Asunto(s)
Crassostrea , Animales , Atrofia Muscular , Suplementos Dietéticos , Serina-Treonina Quinasas TOR , Dexametasona , Mamíferos
9.
Clin Anat ; 37(2): 169-177, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37255275

RESUMEN

The Sihler's stain is a whole-mount nerve staining technique that allows visualization of the nerve distribution and permits mapping of the entire nerve supply patterns of the organs, skeletal muscles, mucosa, skin, and other structures that contain myelinated nerve fibers. Unlike conventional approaches, this technique does not require extensive dissection or slide preparation. To date, the Sihler's stain is the best tool for demonstrating the precise intramuscular branching and distribution patterns of skeletal muscles. The intramuscular neural distribution is used as a guidance tool for the application of botulinum neurotoxin injections. In this review, we have identified and summarized the ideal botulinum neurotoxin injection points for several human tissues.


Asunto(s)
Toxinas Botulínicas , Humanos , Coloración y Etiquetado , Colorantes , Músculo Esquelético/inervación , Inyecciones
10.
Int J Mol Sci ; 25(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731887

RESUMEN

This study explores olive flounder by-product Prozyme2000P (OFBP) hydrolysate as a potential treatment for age-related kidney decline. Ferroptosis, a form of cell death linked to iron overload and oxidative stress, is increasingly implicated in aging kidneys. We investigated whether OFBP could inhibit ferroptosis and improve kidney health. Using TCMK-1 cells, we found that OFBP treatment protected cells from ferroptosis induced by sodium iodate (SI). OFBP also preserved the mitochondria health and influenced molecules involved in ferroptosis regulation. In aging mice, oral administration of OFBP significantly improved kidney health markers. Microscopic examination revealed reduced thickening and scarring in the kidney's filtering units, a hallmark of aging. These findings suggest that OFBP hydrolysate may be a promising therapeutic candidate for age-related kidney decline. By inhibiting ferroptosis, OFBP treatment appears to improve both cellular and structural markers of kidney health. Further research is needed to understand how OFBP works fully and test its effectiveness in more complex models.


Asunto(s)
Ferroptosis , Riñón , Animales , Ferroptosis/efectos de los fármacos , Ratones , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Envejecimiento/efectos de los fármacos , Lenguado/metabolismo , Estrés Oxidativo/efectos de los fármacos , Hidrolisados de Proteína/farmacología , Hidrolisados de Proteína/química , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Masculino , Línea Celular , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/metabolismo , Enfermedades Renales/patología
11.
Surg Radiol Anat ; 46(1): 3-9, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38036923

RESUMEN

BACKGROUND: The aim of this study was to elucidate the anatomical structures of supporting system of the infraorbital area. MATERIALS AND METHODS: Forty-four hemifaces from eleven Korean and eleven Thai cadavers were used to dissect the infraorbital area. Based on the dissection and previous histologic results, they were analyzed. RESULTS: The orbicularis oculi muscle (OOc) had two portions (palpebral and orbital portion) and four subparts (pretarsal, preseptal, prezygomatic, and premaxillary part). The elliptical muscle fiber of OOc was supported by circumferential connective tissue including skin ligament, orbicularis retaining ligament, zygomatic ligament, and zygomatic cutaneous ligament. The vertical muscle fiber, the tear trough muscle fiber, and medial muscular band directly attached to the skin. CONCLUSION: Full of subcutaneous tissue in the tear trough groove, strong attachment to the bone by tear trough ligament and to the skin by tear trough muscle fiber would multiply result in the tear trough on the face.


Asunto(s)
Párpados , Músculos Faciales , Humanos , Mejilla , Rotura , Fibras Musculares Esqueléticas
12.
Aesthet Surg J ; 44(3): 319-326, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37548270

RESUMEN

The utilization of botulinum neurotoxin in the field of body contouring is on the rise. Body contouring procedures typically focus on specific muscle groups such as the superior trapezius, deltoid, and lateral head of the triceps brachii. The authors propose identifying optimal injection sites for botulinum neurotoxin to achieve desired aesthetic contouring of the shoulders and arms. The authors conducted a modified Sihler's staining method on specimens of the superior trapezius, deltoid, and lateral head of the triceps brachii muscles, totaling 16, 14, and 16 specimens, respectively. The neural distribution exhibited the most extensive branching patterns within the horizontal section (between 1/5 and 2/5) and the vertical section (between 2/4 and 4/4) of the superior trapezius muscle. In the deltoid muscle, the areas between the anterior and posterior deltoid bellies, specifically within the range of the horizontal 1/3 to 2/3 lines, showed significant intramuscular arborization. Furthermore, the middle deltoid muscle displayed arborization patterns between 2/3 and the axillary line. Regarding the triceps brachii muscle, the lateral heads demonstrated arborization between 4/10 and 7/10. The authors recommend targeting these regions, where maximum arborization occurs, as the optimal and safest points for injecting botulinum toxin.


Asunto(s)
Toxinas Botulínicas , Humanos , Hombro , Brazo , Músculo Esquelético , Inyecciones
13.
J Am Chem Soc ; 145(42): 23048-23056, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37735109

RESUMEN

Although mRNA delivery technology is very promising, problems in safety and transport arise due to the intrinsically low thermodynamic stability of the current mRNA carriers. Considering that mRNAs are filamentous and a nanotube is one of the most thermodynamically stable shapes among nanoassemblies, a nanotube is one of the most stable supramolecular structures that can be assembled with mRNA. Here, we develop a nanotube-shaped filamentous mRNA delivery platform that shows exceptionally high thermodynamic stability. The key to the development of the mRNA nanotube is the design of self-adjusting supramolecular building blocks (SABs) that have two disparate properties, i.e., dynamic property and stiffness, in a single molecule. The counterbalance of the dynamic property and stiffness in SABs enables the coating of mRNA by winding its way through the flexible and irregular mRNA chain via cooperative interactions. SAB nanotubes with targeting ligands installed show a high uptake efficiency in mammalian cells and controllable gene expression behavior. Thus, the mRNA nanotube provides an enabling technology toward the development of safe and stable mRNA vaccines and therapeutics.


Asunto(s)
Nanotubos , Nanotubos/química , Nanotecnología , Conformación Proteica en Hélice alfa , Termodinámica
14.
Small ; 19(5): e2206561, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36436836

RESUMEN

Surface modification of cathodes using Ni-rich coating layers prevents bulk and surface degradation for the stable operation of Li-ion batteries at high voltages. However, insulating and dense inorganic coating layers often impede charge transfer and ion diffusion kinetics. In this study, the fabrication of dual functional coating materials using metal-organic polyhedra (MOP) with 3D networks within microporous units of Li-ion batteries for surface stabilization and facile ion diffusion is proposed. Zr-based MOP is modified by introducing acyl groups as a chemical linkage (MOPAC), and MOPAC layers are homogenously coated by simple spray coating on the cathode. The coating allow the smooth transport of electrons and ions. MOPAC effectively suppress side reactions between the cathode and electrolyte and protect active materials against aggressive fluoride ions by forming a Li-ion selective passivation film. The MOPAC-coated Ni-rich layered cathode exhibited better cycle retention and enhanced kinetic properties than pristine and MOP-coated cathodes. Reduction of undesirable gas evolution on the cathode by MOPAC is also verified. Microporous MOPAC coating can simultaneously stabilize both the bulk and surface of the Ni-rich layered cathode and maintain good electrochemical reaction kinetics for high-performance Li-ion batteries.

15.
Crit Rev Food Sci Nutr ; 63(14): 1983-2003, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34459311

RESUMEN

The fundamental basis for the human function is provided by skeletal muscle. Advancing age causes selective fiber atrophy, motor unit loss, and hybrid fiber formation resulting in hampered mass and strength, thus referred to as sarcopenia. Influence on the loss of independence of aged adults, contribute toward inclined healthcare costs conveys the injurious impact. The current understating of age-related skeletal muscle changes are addressed in this review, and further discusses mechanisms regulating protein turnover, although they do not completely define the process yet. Moreover, the reduced capacity of muscle regeneration due to impairment of satellite cell activation and proliferation with neuronal, immunological, hormonal factors were brought into the light of attention. Nevertheless, complete understating of sarcopenia requires disentangling it from disuse and disease. Nutritional intervention is considered a potentially preventable factor contributing to sarcopenia. Seafood is a crucial player in the fight against hunger and malnutrition, where it consists of macro and micronutrients. Hence, the review shed light on seafood as a nutritional intrusion in the treatment and prevention of sarcopenia. Understanding multiple factors will provide therapeutic targets in the prevention, treatment, and overcoming adverse effects of sarcopenia.


Asunto(s)
Sarcopenia , Adulto , Humanos , Persona de Mediana Edad , Sarcopenia/prevención & control , Envejecimiento/fisiología , Músculo Esquelético/fisiología , Causalidad , Alimentos Marinos
16.
Nanotechnology ; 34(46)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37531942

RESUMEN

Highly selective etching of silicon nitride over silicon oxide is one of the most important processes especially for the fabrication of vertical semiconductor devices including 3D NAND (Not And) devices. In this study, isotropic dry etching characteristics of SiNxand SiO2using ClF3/Cl2remote plasmas have been investigated. The increase of Cl2percent in ClF3/Cl2gas mixture increased etch selectivity of SiNxover SiO2while decreasing SiNxetch rate. By addition of 15% Cl to ClF3/Cl2, the etch selectivity higher than 500 could be obtained with the SiNxetch rate of ∼8 nm min-1, and the increase of Cl percent to 20% further increased the etch selectivity to higher than 1000. It was found that SiNxcan be etched through the reaction from Si-N to Si-F and Si-Cl (also from Si-Cl to Si-F) while SiO2can be etched only through the reaction from Si-O to Si-F, and which is also in extremely low reaction at room temperature. When SiNx/SiO2layer stack was etched using ClF3/Cl2(15%), extremely selective removal of SiNxlayer in the SiNx/SiO2layer stack could be obtained without noticeable etching of SiO2layer in the stack and without etch loading effect.

17.
Appl Opt ; 62(24): 6425-6429, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37706835

RESUMEN

An asymmetric Mach-Zehnder interferometer (AMZI) is an essential device to generate pulse pairs in quantum key distribution systems. An AMZI based on a dual-chip coupling structure in a silica-on-silicon planar light wave circuit platform is proposed, which includes a variable optical splitter (VOS), a delay line (DL), and a directional coupler (DC). The AMZI chip is divided into a VOS-DL part and a DC part, and the two parts are independently manufactured and then coupled. Since the DC part occupies the smallest area of the AMZI chip and is most sensitive to manufacturing errors, separate production can reduce the process difficulty and fabrication errors. In the experiment, balanced pulse pairs with a delay time of 402 ps are obtained in the condition of single photon transmission, and the excess loss is 0.8 dB. This dual-chip coupling structure can improve the yield and reduce the manufacturing cost when producing large chips.

18.
Mar Drugs ; 21(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37103370

RESUMEN

In the present investigation, 24-methylcholesta-5(6), 22-diene-3ß-ol (MCDO), a major phytosterol was isolated from the cultured marine diatom, Phaeodactylum tricornutum Bohlin, and in vitro and in vivo anti-inflammatory effects were determined. MCDO demonstrated very potent dose-dependent inhibitory effects on the production of nitric oxide (NO) and prostaglandin E2 (PGE2) against lipopolysaccharide (LPS)-induced RAW 264.7 cells with minimal cytotoxic effects. MCDO also demonstrated a strong and significant suppression of pro-inflammatory cytokines of interleukin-1ß (IL-1ß) production, but no substantial inhibitory effects were observed on the production of cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) at the tested concentrations against LPS treatment on RAW macrophages. Western blot assay confirmed the suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions against LPS-stimulated RAW 264.7 cells. In addition, MCDO was assessed for in vivo anti-inflammatory effects using the zebrafish model. MCDO acted as a potent inhibitor for reactive oxygen species (ROS) and NO levels with a protective effect against the oxidative stress induced by LPS in inflammatory zebrafish embryos. Collectively, MCDO isolated from the cultured marine diatom P. tricornutum exhibited profound anti-inflammatory effects both in vitro and in vivo, suggesting that this major sterol might be a potential treatment for inflammatory diseases.


Asunto(s)
Diatomeas , Animales , Diatomeas/metabolismo , Pez Cebra/metabolismo , FN-kappa B/metabolismo , Lipopolisacáridos/farmacología , Antiinflamatorios/farmacología , Transducción de Señal , Citocinas/metabolismo , Interleucina-6/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ciclooxigenasa 2/metabolismo
19.
Mar Drugs ; 21(12)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38132945

RESUMEN

Muscle atrophy is a complex physiological condition caused by a variety of reasons, including muscle disuse, aging, malnutrition, chronic diseases, immobilization, and hormonal imbalance. Beyond its effect on physical appearance, this condition significantly reduces the quality of human life, thus warranting the development of preventive strategies. Although exercising is effective in managing this condition, it is applicable only for individuals who can engage in physical activities and are not bedridden. A combination of exercise and nutritional supplementation has emerged as a more advantageous approach. Here, we evaluated the effects of enzyme-assisted hydrolysates of Mytilus edulis prepared using Protamex (PMH), Alcalase (AMH), or Flavourzyme (FMH) in protecting against muscle atrophy in a dexamethasone (Dex)-induced muscular atrophy model in vitro and in vitro. Alcalase-assisted M. edulis hydrolysate (AMH) was the most efficient among the tested treatments and resulted in higher protein recovery (57.06 ± 0.42%) and abundant amino acid composition (43,158 mg/100 g; 43.16%). AMH treatment also escalated the proliferation of C2C12 cells while increasing the total number of nuclei, myotube coverage, and myotube diameter. These results were corroborated by a successful reduction in the levels of proteins responsible for muscle atrophy, including E3 ubiquitin ligases, and an increase in the expression of proteins associated with muscle hypertrophy, including myogenin and MyHC. These results were further solidified by the successful enhancement of locomotor ability and body weight in zebrafish following AMH treatment. Thus, these findings highlight the potential of AMH in recovery from muscle atrophy.


Asunto(s)
Mytilus edulis , Animales , Humanos , Subtilisinas , Pez Cebra , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/prevención & control , Atrofia Muscular/inducido químicamente , Fibras Musculares Esqueléticas , Músculo Esquelético
20.
Mar Drugs ; 21(12)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38132961

RESUMEN

Inflammatory diseases caused by air pollution, especially from particulate matter (PM) exposure, have increased daily. Accordingly, attention to treatment or prevention for these inflammatory diseases has grown. Natural products have been recognized as promising sources of cures and prevention for not only inflammatory but also diverse illnesses. As part of our ongoing study to discover bioactive compounds from marine microorganisms, we isolated streptinone, a new indanone derivative (1), along with three known diketopiperazines (2-4) and piericidin A (5), from a marine sediment-derived Streptomyces massiliensis by chromatographic methods. The structure of 1 was elucidated based on the spectroscopic data analysis. The relative and absolute configurations of 1 were determined by 1H-1H coupling constants, 1D NOESY, and ECD calculation. The anti-inflammatory activities of 1 were evaluated through enzyme-linked immunosorbent assay (ELISA), Western blot, and qPCR. Compound 1 suppressed the production of nitric oxide (NO), prostaglandin E2 (PGE2), and pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1ß, by inhibiting the Toll-like receptor (TLR)-mediated nuclear factor kappa B (NF-κB) signaling pathway. Therefore, compound 1 could potentially be used as an agent in the prevention and treatment of diverse inflammatory disorders caused by particulate matter.


Asunto(s)
Inflamación , Material Particulado , Humanos , Material Particulado/efectos adversos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Transducción de Señal , FN-kappa B/metabolismo , Antiinflamatorios/uso terapéutico , Citocinas/metabolismo , Lipopolisacáridos/farmacología
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