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1.
Opt Express ; 32(3): 3085-3099, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297539

RESUMEN

This paper presents a novel co-packaging approach through on-chip hybrid laser integration with photonic circuits using photonic wire bonding. The process involves die-bonding a low-cost semiconductor distributed-feedback (DFB) laser into a deep trench on a silicon-on-insulator (SOI) chip and coupling it to the silicon circuitry through photonic wire bonding (PWB). After characterizing the power-current-voltage (LIV) and optical spectrum of the laser, a wavelength-current relationship utilizing its tunability through self-heating a swept-frequency laser (SFL) is developed. Photonic integrated circuit (PIC) resonators are successfully characterized using the SFL method, demonstrating signal detection with a quality factor comparable to measurements conducted with an off-chip benchtop laser.

2.
Entropy (Basel) ; 26(5)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38785671

RESUMEN

Finite mixture of linear regression (FMLR) models are among the most exemplary statistical tools to deal with various heterogeneous data. In this paper, we introduce a new procedure to simultaneously determine the number of components and perform variable selection for the different regressions for FMLR models via an exponential power error distribution, which includes normal distributions and Laplace distributions as special cases. Under some regularity conditions, the consistency of order selection and the consistency of variable selection are established, and the asymptotic normality for the estimators of non-zero parameters is investigated. In addition, an efficient modified expectation-maximization (EM) algorithm and a majorization-maximization (MM) algorithm are proposed to implement the proposed optimization problem. Furthermore, we use the numerical simulations to demonstrate the finite sample performance of the proposed methodology. Finally, we apply the proposed approach to analyze a baseball salary data set. Results indicate that our proposed method obtains a smaller BIC value than the existing method.

3.
Pulm Pharmacol Ther ; 81: 102228, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37295666

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic fatal disease of unknown etiology. Its pathological manifestations include excessive proliferation and activation of fibroblasts and deposition of extracellular matrix. Endothelial cell-mesenchymal transformation (EndMT), a novel mechanism that generates fibroblast during IPF, is responsible for fibroblast-like phenotypic changes and activation of fibroblasts into hypersecretory cells. However, the exact mechanism behind EndMT-derived fibroblasts and activation is uncertain. Here, we investigated the role of sphingosine 1-phosphate receptor 1 (S1PR1) in EndMT-driven pulmonary fibrosis. METHODS: We treated C57BL/6 mice with bleomycin (BLM) in vivo and pulmonary microvascular endothelial cells with TGF-ß1 in vitro. Western blot, flow cytometry, and immunofluorescence were used to detect the expression of S1PR1 in endothelial cells. To evaluate the effect of S1PR1 on EndMT and endothelial barrier and its role in lung fibrosis and related signaling pathways, S1PR1 agonist and antagonist were used in vitro and in vivo. RESULTS: Endothelial S1PR1 protein expression was downregulated in both in vitro and in vivo models of pulmonary fibrosis induced by TGF-ß1 and BLM, respectively. Downregulation of S1PR1 resulted in EndMT, indicated by decreased expression of endothelial markers CD31 and VE-cadherin, increased expression of mesenchymal markers α-SMA and nuclear transcription factor Snail, and disruption of the endothelial barrier. Further mechanistic studies found that stimulation of S1PR1 inhibited TGF-ß1-mediated activation of the Smad2/3 and RhoA/ROCK1 pathways. Moreover, stimulation of S1PR1 attenuated Smad2/3 and RhoA/ROCK1 pathway-mediated damage to endothelial barrier function. CONCLUSIONS: Endothelial S1PR1 provides protection against pulmonary fibrosis by inhibiting EndMT and attenuating endothelial barrier damage. Accordingly, S1PR1 may be a potential therapeutic target in progressive IPF.


Asunto(s)
Fibrosis Pulmonar Idiopática , Fibrosis Pulmonar , Ratones , Animales , Fibrosis Pulmonar/patología , Factor de Crecimiento Transformador beta1/metabolismo , Células Endoteliales/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/uso terapéutico , Ratones Endogámicos C57BL , Bleomicina/farmacología , Transición Epitelial-Mesenquimal , Fibroblastos/metabolismo , Fibrosis Pulmonar Idiopática/patología
4.
Phys Chem Chem Phys ; 25(11): 7783-7793, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36857651

RESUMEN

Much of biological electron transfer occurs between proteins. These molecular processes usually involve molecular recognition and intermolecular electron transfer (inter-ET). The inter-ET reaction between copper-containing nitrite reductase (CuNiR) and partner protein pseudoazurin (PAz) is the first step in denitrification, which is affected by intermolecular association. However, the transient interaction between CuNiR and PAz and the indistinct inter-ET pathway pose challenges for people to understand the biological functions of the CuNiR-PAz complex. Thus, molecular dynamics simulation and quantum mechanical calculation were used to investigate the question in this study. The interaction of the interface residues was determined through hydrogen bonds, root-mean-square deviation, root-mean-square fluctuation, the dynamics cross-correlation matrix, and molecular mechanics Poisson-Boltzmann surface area of molecular dynamics simulations. The interactions among the residues Glu89, Gly200, Asp205, Asn91, Glu204, Thr92, and Met141 on CuNiR and the residues Lys109, Ala15, Lys10, Asn9, Ile110, Met84, and Met16 on PAz are responsible for the stabilization of the complex. The binding free energy is up to -25.33 kcal mol-1. We compared the wild-type and mutant (M84A) interfacial optimized complex models at the CAM-B3LYP level with Grimme dispersion corrections (GD3) to confirm Met84 as a relay station for promoting the inter-ET. Additionally, to test whether Met84 may combine with the adjacent Met141 to form a special two-center, three-electron (S∴S)+ structure to promote the inter-ET, QM/MM was further performed to discuss the possibility of generating an electron stepping stone. Our study will promote a deep understanding of the stable protein-protein interaction, and the identified inter-residue interaction will be theoretical guidance for enhancing the catalytic activity of CuNiR in denitrification.


Asunto(s)
Cobre , Simulación de Dinámica Molecular , Humanos , Cobre/química , Electrones , Oxidación-Reducción , Nitrito Reductasas/química
5.
Pestic Biochem Physiol ; 195: 105560, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37666596

RESUMEN

Fructose 1, 6-diphosphate (FDP) is an endogenous intermediate in the glycolytic pathway, as well as an allosteric activator of phosphofructokinase (PFK). Based on the role in promoting glycolysis, FDP has been widely used as a therapeutic agent for mitigating the damage of endotoxemia and ischemia/reperfusion in clinical practice. However, the effect of exogenous FDP-induced glycolysis activation on insect carbohydrate metabolism and chitin synthesis remains largely unclear. Here, we investigated for the first time the effects of FDP-Na, an allosteric activator of PFK, on the growth and development of Hyphantria cunea larvae, a serious defoliator in agriculture and forestry, especially on glycolysis and chitin synthesis. The results showed that FDP-Na significantly restrained the growth and development of H. cunea larvae and resulted in larval lethality. After treatment with FDP-Na, hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were significantly activated, and HcHK2, HcPFK, HcPK were dramatically upregulated, which suggested that FDP-Na enhanced glycolysis in H. cunea larvae. Meanwhile, FDP-Na also distinctly impacted chitin biosynthesis by disturbing transcriptions of genes in the chitin synthesis pathway, resulting in changes of chitin contents in the midgut and epidermis of H. cunea larvae. Therefore, we considered that FDP-Na caused the growth and development arrest, and impacted chitin biosynthesis, probably by disturbing in vivo glycolysis and carbohydrate metabolism in H. cunea larvae. The findings provide a new perspective on the mechanism by which glycolysis regulates insect growth and development, and lay the foundation for exploring the potential application of glycolysis activators in pest control as well.


Asunto(s)
Difosfatos , Mariposas Nocturnas , Animales , Larva , Glucólisis , Fosfofructoquinasas , Quitina/farmacología
6.
J Cell Mol Med ; 26(12): 3313-3322, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35560773

RESUMEN

Renal fibrosis is an important pathological feature of diabetic kidney disease (DKD), manifested as tubular interstitial fibrosis, tubular atrophy, glomerulosclerosis and damage to the normal structure of the kidney. Renal fibrosis can eventually develop into renal failure. A better understanding of renal fibrosis in DKD is needed due to clinical limitations of current anti-fibrotic drugs in terms of effectiveness, cost-effectiveness and side effects. Fibrosis is characterized by local excessive deposition of extracellular matrix, which is derived from activated myofibroblasts to increase its production or specific tissue inhibitors of metalloproteinases to reduce its degradation. In recent years, endothelial-mesenchymal transition (EndMT) has gradually integrated into the pathogenesis of fibrosis. In animal models of diabetic kidney disease, it has been found that EndMT is involved in the formation of renal fibrosis and multiple signalling pathways such as TGF-ß signalling pathway, Wnt signalling pathway and non-coding RNA network participate in the regulation of EndMT during fibrosis. Here, we mainly review EndMT regulation and targeted therapy of renal fibrosis in DKD.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Animales , Diabetes Mellitus/patología , Nefropatías Diabéticas/patología , Células Endoteliales/metabolismo , Transición Epitelial-Mesenquimal/genética , Fibrosis , Riñón/patología , Vía de Señalización Wnt
7.
Pestic Biochem Physiol ; 187: 105216, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36127058

RESUMEN

E74 is a key transcription factor induced by 20E, which plays a broad role in many physiological events during insect growth and development, including vitellogenesis, organ remodeling and new tissue formation, programmed cell death and metamorphosis. However, whether it is involved in regulating insect chitin biosynthesis remains largely unclear. Here, the E74 gene was identified for the first time from Hyphantria cunea, a notorious defoliator of forestry. Thereafter, the role of HcE74 in regulating growth, development and chitin synthesis in H. cunea larvae was evaluated. Bioinformatics analysis showed that HcE74 shared the highest identity (95.53%) with E74A of Spodoptera litura, which belonged to Ets superfamily. The results of RNAi bioassay showed that the larval mortality on 6 d after HcE74 knockdown was up to 51.11 ± 6.94%. Meanwhile, a distinct developmental deformity phenotype was found when HcE74 was silenced. These results indicated that HcE74 plays an important role in the development and molting of H. cunea larvae. Moreover, HcE74 knockdown also significantly decreased the expression of four key genes related to chitin synthesis, including glucose-6-phosphate isomerase (HcG6PI), UDP-N-acetylglucosamine pyrophosphorylase (HcUAP), chitin synthetase A (HcCHSA), and chitin synthetase B (HcCHSB). As a result, the content of chitin in midgut and epidermis decreased by 0.54- and 0.08-fold, respectively. Taken together, these results demonstrated that HcE74 not only plays a critical role in the growth and molting of H. cunea larvae, but also probably participates in the transcriptional regulation of genes involved in chitin biosynthesis.


Asunto(s)
Glucosa-6-Fosfato Isomerasa , Mariposas Nocturnas , Animales , Quitina , Glucosa-6-Fosfato Isomerasa/metabolismo , Insectos , Larva , Ligasas/metabolismo , Factores de Transcripción
8.
Pestic Biochem Physiol ; 188: 105245, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464356

RESUMEN

Glutamine-fructose-6-phosphate transaminase (GFAT) has been reported to regulate the hexosamine biosynthetic pathway as the first rate-limiting enzyme. As a key enzyme that catalyzes the substrate of glycosylation modification, which has a wide-ranging effect on cellular functions. However, there are few studies on the relationship between GFAT and chitin metabolism in insects. In the present study, the GFAT gene from Hyphantria cunea was identified based on transcriptome and bioinformatic analysis. The role of HcGFAT in regulating development and chitin synthesis was analyzed by RNA interference (RNAi) in H. cunea larvae. The full-length HcGFAT gene (2028 bp) encodes a 676 amino acid (aa) polypeptide had typical structural features of the SIS and Gn_AT_II superfamily. Phylogenetic analyses showed that GFAT of H. cunea shares the highest homology and identity with GFAT of Ostrinia furnacalis. Expression profiles indicated that HcGFAT was expressed throughout larval, pupal and three tissues (midgut, fat body, epidermis), and highly expressed in the last instar of larvae and strongly expressed in epidermis among three tissues. Bioassay results showed that knockdown of HcGFAT repressed larval growth and development, resulting in a significant loss of larval body weight. Meanwhile, HcGFAT knockdown also significantly caused larval developmental deformity. Knockdown of HcGFAT regulated the expression of four other critical genes in the chitin synthesis pathway (HcGNA, HcPAGM, HcUAP, HcCHSA), and ultimately resulted in decreased chitin content in the epidermis. In summary, these findings indicated that GFAT plays a critical role in larval growth and development, as well as chitin synthesis in H. cunea.


Asunto(s)
Aminoácidos , Quitina , Animales , Larva/genética , Filogenia , Pupa
9.
Pestic Biochem Physiol ; 183: 105083, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35430073

RESUMEN

Metformin, considered to be a potent AMPK activator, is widely used for clinical therapy of cancer and diabetes due to its distinct function in regulating cell energy balance and body metabolism. However, the effect of metformin-induced AMPK activation on the growth and development of insects remains largely unknown. In the present study, we focused on the role of metformin in regulating the growth and development of Hyphantria cunea, a notorious defoliator in the forestry. Firstly, we obtained the complete coding sequences of HcAMPKα2, HcAMPKß1, HcAMPKγ2 from H. cunea, which encoded a protein of 512, 281, and 680 amino acids respectively. Furthermore, the phylogenetic analysis revealed that these three subunits were highly homologous with the AMPK subunits from other lepidopteran species. According to the bioassay, we found metformin remarkably restrained the growth and development of H. cunea larvae, and caused molting delayed and body weight reduced. In addition, expressions of HcAMPKα2, HcAMPKß1, and HcAMPKγ2 were upregulated 3.30-, 5.93- and 5.92-folds at 24 h after treatment, confirming that metformin activated AMPK signaling at the transcriptional level in H. cunea larvae. Conversely, the expressions of two vital Halloween genes (HcCYP306A1 and HcCYP314A1) in the 20E synthesis pathway were remarkably suppressed by metformin. Thus, we presumed that metformin delayed larval molting probably by impeding 20E synthesis in the H. cunea larvae. Finally, we found that metformin accelerated glycogen breakdown, elevated in vivo trehalose level, promoted chitin synthesis, and upregulated transcriptions of the genes in chitin synthesis pathway. Taken together, the findings provide a new insight into the molecular mechanisms by which AMPK regulates carbohydrate metabolism and chitin synthesis in insects.


Asunto(s)
Metformina , Mariposas Nocturnas , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Quitina/metabolismo , Larva/metabolismo , Metformina/metabolismo , Metformina/farmacología , Muda , Mariposas Nocturnas/genética , Filogenia
10.
Pestic Biochem Physiol ; 179: 104961, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34802511

RESUMEN

As a typical glycolytic inhibitor, 3-bromopyruvate (3-BrPA) has been extensively studied in cancer therapy in recent decades. However, few studies focused on 3-BrPA in regulating the growth and development of insects, and the relationship and regulatory mechanism between glycolysis and chitin biosynthesis remain largely unknown. The Hyphantria cunea, named fall webworm, is a notorious defoliator, which caused a huge economic loss to agriculture and forestry. Here, we investigated the effects of 3-BrPA on the growth and development, glycolysis, carbohydrate homeostasis, as well as chitin synthesis in H. cunea larvae. To elucidate the action mechanism of 3-BrPA on H. cunea will provide a new insight for the control of this pest. The results showed that 3-BrPA dramatically restrained the growth and development of H. cunea larvae and resulted in larval lethality. Meanwhile, we confirmed that 3-BrPA caused a significant decrease in carbohydrate, adenosine triphosphate (ATP), pyruvic acid (PA), and triglyceride (TG) levels by inhibiting glycolysis in H. cunea larvae. Further studies indicated that 3-BrPA significantly affected the activities of hexokinase (HK), phosphofructokinase (PFK), pyruvate kinase (PK), glucose 6-phosphate dehydrogenase (G6PDH) and trehalase, as well as expressions of the genes related to glycolysis, resulting in carbohydrate homeostasis disorder. Moreover, it was found that 3-BrPA enhanced 20-hydroxyecdysone (20E) signaling by upregulating HcCYP306A1 and HcCYP314A1, two critical genes in 20E synthesis pathway, and accelerated chitin synthesis by upregulating transcriptional levels of genes in the chitin synthesis pathway in H. cunea larvae. Taken together, our findings provide a novel insight into the mechanism of glycolytic inhibitor in regulating the growth and development of insects, and lay a foundation for the potential application of glycolytic inhibitors in pest control as well.


Asunto(s)
Carbohidratos , Glucólisis , Animales , Homeostasis , Larva , Piruvatos
11.
Plant Cell Environ ; 43(5): 1130-1147, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32012309

RESUMEN

Hydrogen sulfide (H2 S) is emerging as an important signalling molecule that regulates plant growth and abiotic stress responses. However, the roles of H2 S in symbiotic nitrogen (N) assimilation and remobilization have not been characterized. Therefore, we examined how H2 S influences the soybean (Glycine max)/rhizobia interaction in terms of symbiotic N fixation and mobilization during N deficiency-induced senescence. H2 S enhanced biomass accumulation and delayed leaf senescence through effects on nodule numbers, leaf chlorophyll contents, leaf N resorption efficiency, and the N contents in different tissues. Moreover, grain numbers and yield were regulated by H2 S and rhizobia, together with N accumulation in the organs, and N use efficiency. The synergistic effects of H2 S and rhizobia were also demonstrated by effects on the enzyme activities, protein abundances, and gene expressions associated with N metabolism, and senescence-associated genes (SAGs) expression in soybeans grown under conditions of N deficiency. Taken together, these results show that H2 S and rhizobia accelerate N assimilation and remobilization by regulation of the expression of SAGs during N deficiency-induced senescence. Thus, H2 S enhances the vegetative and reproductive growth of soybean, presumably through interactions with rhizobia under conditions of N deficiency.


Asunto(s)
Glycine max/metabolismo , Sulfuro de Hidrógeno/metabolismo , Bacterias Fijadoras de Nitrógeno/metabolismo , Nitrógeno/metabolismo , Envejecimiento/metabolismo , Western Blotting , Clorofila/metabolismo , Electroforesis en Gel de Poliacrilamida , Leghemoglobina/metabolismo , Nitrógeno/deficiencia , Fijación del Nitrógeno , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Raíces de Plantas/metabolismo , Raíces de Plantas/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Nódulos de las Raíces de las Plantas/metabolismo , Nódulos de las Raíces de las Plantas/fisiología , Glycine max/fisiología
12.
Pestic Biochem Physiol ; 163: 64-75, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31973871

RESUMEN

Fenoxycarb as a juvenile hormone analogue and methoxyfenozide (RH-2485) as a 20-hydroxyecdysone (20E) agonist are two main insect growth regulators (IGRs) used for pest control, whose insecticidal mechanisms had been widely reported in past decades. However, there were few studies focused on their effects on the carbohydrate metabolism of insects. Here, we reported that two IGRs (fenoxycarb and RH-2485) significantly affected growth and development of L. dispar larvae and caused larval lethality. Furthermore, both contens of three sugars (glycogen, threhalose, glucose) in four tissues (fat body, midgut, hemolymph and epidermis) and trehalase activity in three tissues (fat body, midgut and hemolymph) of L. dispar larvae were markedly affected by these two IGRs. Moreover, we found that mRNA expression levels of LdTPS, LdTre1 and LdTre2 in L. dispar larvae were dramatically suppressed by two IGRs. Additionally, chitin content in both midgut and epidermis decreased significantly after L. dispar larvae treated with fenoxycarb or RH-2485. Summarily, these results indicated that these two IGRs disturbed glycometabolism in L. dispar larvae, resulting in impeding chitin synthesis, generating new epidermis failure, disrupting molting and larval lethality in the end.


Asunto(s)
Quitina , Hormonas Juveniles , Animales , Hidrazinas , Larva , Fenilcarbamatos
13.
Angew Chem Int Ed Engl ; 59(18): 7097-7105, 2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-32049411

RESUMEN

Gold(I) N-heterocyclic carbene (AuI -NHC) complexes have emerged as potential anticancer agents owing to their high cytotoxicity and stability. Integration of their above unique functions with customized aggregation-induced emission (AIE) luminogens to achieve specific bioimaging and efficient theranostics to cancer is highly desirable but is rarely studied. Now, a series of novel AuI -NHC compounds were developed with AIE characteristics. A complex with a PPh3 ligand was selected out as it could achieve both prominent specific imaging of various cancer cells and efficient inhibition of their growth with negligible toxic effects on normal cells due to the targeting binding and strong inhibition towards thioredoxin reductase. This complex could also act as a powerful radiosensitizer to boost the anticancer efficacy with performance superior to that of popularly used auranofin. It holds great potential as a specific and effective theranostic drug in cancer diagnosis and precise therapy.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Oro/farmacología , Compuestos Heterocíclicos/farmacología , Metano/análogos & derivados , Imagen Óptica , Nanomedicina Teranóstica , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Oro/química , Compuestos Heterocíclicos/química , Humanos , Metano/química , Metano/farmacología , Estructura Molecular , Fotoquimioterapia , Medicina de Precisión
14.
Mol Plant Microbe Interact ; 32(8): 972-985, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31204904

RESUMEN

The rhizobium-legume symbiotic system is crucial for nitrogen cycle balance in agriculture. Hydrogen sulfide (H2S), a gaseous signaling molecule, may regulate various physiological processes in plants. However, whether H2S has regulatory effect in this symbiotic system remains unknown. Herein, we investigated the possible role of H2S in the symbiosis between soybean (Glycine max) and rhizobium (Sinorhizobium fredii). Our results demonstrated that an exogenous H2S donor (sodium hydrosulfide [NaHS]) treatment promoted soybean growth, nodulation, and nitrogenase (Nase) activity. Western blotting analysis revealed that the abundance of Nase component nifH was increased by NaHS treatment in nodules. Quantitative real-time polymerase chain reaction data showed that NaHS treatment upregulated the expressions of symbiosis-related genes nodA, nodC, and nodD of S. fredii. In addition, expression of soybean nodulation marker genes, including early nodulin 40 (GmENOD40), ERF required for nodulation (GmERN), nodulation signaling pathway 2b (GmNSP2b), and nodulation inception genes (GmNIN1a, GmNIN2a, and GmNIN2b), were upregulated. Moreover, the expressions of glutamate synthase (GmGOGAT), asparagine synthase (GmAS), nitrite reductase (GmNiR), ammonia transporter (GmSAT1), leghemoglobin (GmLb), and nifH involved in nitrogen metabolism were upregulated in NaHS-treated soybean roots and nodules. Together, our results suggested that H2S may act as a positive signaling molecule in the soybean-rhizobia symbiotic system and enhance the system's nitrogen fixation ability.


Asunto(s)
Glycine max , Sulfuro de Hidrógeno , Fijación del Nitrógeno , Nodulación de la Raíz de la Planta , Rhizobium , Gasotransmisores/farmacología , Sulfuro de Hidrógeno/farmacología , Fijación del Nitrógeno/efectos de los fármacos , Nodulación de la Raíz de la Planta/efectos de los fármacos , Rhizobium/fisiología , Glycine max/microbiología , Simbiosis/efectos de los fármacos
15.
Small ; 15(50): e1905080, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31721436

RESUMEN

Two-photon photodynamic therapy (TP-PDT) is emerging as a powerful strategy for stereotactic targeting of diseased areas, but ideal photosensitizers (PSs) are currently lacking. This work reports a smart PS with aggregation-induced emission (AIE) feature, namely DPASP, for TP-PDT with excellent performances. DPASP exhibits high affinity to mitochondria, superior photostability, large two-photon absorption cross section as well as efficient reactive oxygen species generation, enabling it to achieve photosensitization both in vitro and in vivo under two-photon excitation. Moreover, its capability of stereotactic ablation of targeted cells with high-precision is also successfully demonstrated. All these merits make DPASP a promising TP-PDT candidate for accurate ablation of abnormal tissues with minimal damages to surrounding areas in the treatment of various diseases.


Asunto(s)
Fotoquimioterapia , Fotones , Fármacos Fotosensibilizantes/farmacología , Células A549 , Animales , Humanos , Ratones Desnudos , Fenómenos Ópticos
16.
Pestic Biochem Physiol ; 153: 9-16, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30744901

RESUMEN

Our previous studies had identified that both crude extracts and total alkaloid from Chelidonium majus exerted a significant antifeeding and larval lethality on Lymantria dispar. Moreover, sanguinarine, chelidonine, berberine hydrochloride and coptisine were the main alkaloid in C. majus exerting toxicity to L. dispar. In this paper, we evaluated the insecticidal and antifeeding activities of each alkaloid on the 3rd instar L. dispar larvae by bioassay. Meanwhile, the effects of alkaloids from C. majus on the activities and mRNA levels of three main digestive enzymes in L. dispar larvae were investigated. The results indicated that sanguinarine possessed the strongest insecticidal activity with a LD50 value of 4.963 µg/larva, and the coptisine showed little lethality to 3 rd instar L. dispar larvae among four alkaloids from C. majus. The insecticidal capacity of four alkaloids on 3rd instar L. dispar larvae was in the following decreasing order of sanguinarine > chelidonine > berberine hydrochloride > coptisine. Similarly, except coptisine, the other three alkaloids significantly reduced food intakes of third instar L. dispar larvae and suppressed activities of three digestive enzymes (α-amylase, lipase and total protease) simultaneously. Finally, qRT-PCR analysis revealed that the transcriptions of α-amylase, lipase and serine protease were affected by sanguinarine. Especially, at 48 h after treatment, the mRNA expressions of those digestive enzymes were significantly suppressed by sanguinarine. In conclusion, we suggested that alkaloids from C. majus induced antifeeding and larval lethality on L. dispar larvae by suppressing food intake and digestive enzymes in L. dispar. Our findings provide a novel insight into evaluating the antifeeding and insecticidal properties of C. majus, which afford a new strategy for integrated pest management programs as well.


Asunto(s)
Benzofenantridinas/toxicidad , Chelidonium , Insecticidas/toxicidad , Isoquinolinas/toxicidad , Larva/efectos de los fármacos , Mariposas Nocturnas/efectos de los fármacos , Amilasas/metabolismo , Animales , Berberina/toxicidad , Ingestión de Alimentos/efectos de los fármacos , Tracto Gastrointestinal/enzimología , Larva/fisiología , Lipasa/metabolismo , Mariposas Nocturnas/fisiología , Péptido Hidrolasas/metabolismo
17.
J Am Chem Soc ; 140(16): 5588-5598, 2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29630372

RESUMEN

Heterocyclic polymers have gained enormous attention for their unique functionalities and wide applications. In contrast with the well-studied polymer systems with five- or six-membered heterocycles, functional polymers with readily openable small-ring heterocycles have rarely been explored due to their large synthetic difficulty. Herein, a facile one-pot multicomponent polymerization to such polymers is developed. A series of functional polymers with multisubstituted and heteroatom-rich azetidine frameworks are efficiently generated at room temperature in high atom economy from handy monomers. The four-membered azetidine rings in the polymer skeletons can be easily transformed into amide and amidine moieties via a fast and efficient acid-mediated ring-opening reaction, producing brand-new polymeric materials with distinctive properties. All the as-prepared azetidine-containing polymers exhibit intrinsic visible luminescence in the solid state under long-wavelength UV irradiation even without conventionally conjugated structures. Such unconventional luminescence is attributed to the clusteroluminogens formed by through-space electronic interactions of heteroatoms and phenyl rings. All the obtained polymers show excellent optical transparency, high and tunable refractive indices, low optical dispersions and good photopatternability, which make them promising materials in various advanced electronic and optoelectronic devices. The ring-opened polymers can also function as a lysosome-specific fluorescent probe in biological imaging.

18.
Eur Arch Otorhinolaryngol ; 272(2): 445-51, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24643849

RESUMEN

This study was designed to explore the effectiveness and safety of the combination of bronchoscopic interventions and percutaneous modalities in treating thyroid cancers with airway invasion. A total of 13 patients, 5 men and 8 women, were retrospectively included into this study. All patients received bronchoscope treatment. Rigid bronchoscope was used to explore, ventilate, and dilate airway obstruction for temporary control in nine patients. Tumors were scavenged by CO2 cryosurgery combined with argon plasma coagulation (APC) in 11 patients. Four covered Z-type recoverable tracheal stents were selected for four patients. All patients had good airway control and palliative respiratory symptoms following treatments. Ten patients were further treated with CT guided (125)I seed permanent implantation, and one patient was treated with argon-helium cryoablation. The median local control was 22 months (10-55 months). The follow-up period ranged from 10 to 55 months (median 22 months). Three patients (23.1%) died of local recurrence, one of whom was due to airway obstruction and poor physical condition, two of whom with bleeding from relapsed tumor. One patient (7.7%) died of acute myocardial infraction. Nine patients (69.2%) were still alive according to the last follow-up. (125)I seed implantation and argon-helium cryoablation did not induce apparent complications. The combination of bronchoscopic interventions and percutaneous modalities might be a feasible and safe method for thyroid cancer patients with airway invasion.


Asunto(s)
Obstrucción de las Vías Aéreas/cirugía , Broncoscopía/métodos , Criocirugía/métodos , Coagulación con Láser/métodos , Neoplasias de la Tiroides/cirugía , Anciano , Anciano de 80 o más Años , Obstrucción de las Vías Aéreas/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Neoplasias de la Tiroides/complicaciones , Neoplasias de la Tiroides/patología , Resultado del Tratamiento
19.
Insects ; 15(3)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38535372

RESUMEN

X-ray irradiation and modified atmospheres (MAs) provide eco-friendly, chemical-free methods for pest management. Although a low-oxygen atmospheric treatment improves the performance of some irradiated insects, its influence on the irradiation of quarantine insects and its impacts on pest control efficacy have yet to be investigated. Based on bioassay results, this study employed direct immersion solid-phase microextraction (DI-SPME) combined with gas chromatography-mass spectrometry (GC-MS) to determine metabolic profiles of late third-instar B. dorsalis larvae under normoxia (CON, Air), hypoxia (95% N2 + 5% O2, HY), super-hypoxia (99.5% N2 + 0.5% O2, Sup-HY), irradiation-alone (116 Gy, IR-alone), hypoxia + irradiation (HY + IR) and super-hypoxia + irradiation (Sup-HY + IR). Our findings reveal that, compared to the IR-alone group, the IR treatment under HY and Sup-HY (HY + IR and Sup-HY + IR) increases the larval pupation of B. dorsalis, and weakens the delaying effect of IR on the larval developmental stage. However, these 3 groups further hinder adult emergence under the phytosanitary IR dose of 116 Gy. Moreover, all IR-treated groups, including IR-alone, HY + IR, and Sup-HY + IR, lead to insect death as a coarctate larvae or pupae. Pathway analysis identified changed metabolic pathways across treatment groups. Specifically, changes in lipid metabolism-related pathways were observed: 3 in HY vs. CON, 2 in Sup-HY vs. CON, and 5 each in IR-alone vs. CON, HY + IR vs. CON, and Sup-HY + IR vs. CON. The treatments of IR-alone, HY + IR, and Sup-HY + IR induce comparable modifications in metabolic pathways. However, in the HY + IR, and Sup-HY + IR groups, the third-instar larvae of B. dorsalis demonstrate significantly fewer changes. Our research suggests that a low-oxygen environment (HY and Sup-HY) might enhance the radiation tolerance in B. dorsalis larvae by stabilizing lipid metabolism pathways at biologically feasible levels. Additionally, our findings indicate that the current phytosanitary IR dose contributes to the effective management of B. dorsalis, without being influenced by radioprotective effects. These results hold significant importance for understanding the biological effects of radiation on B. dorsalis and for developing IR-specific regulatory guidelines under MA environments.

20.
Plants (Basel) ; 13(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38611507

RESUMEN

The investigation into trade-offs among plant functional traits sheds light on how plants strategically balance growth and survival when facing environmental stress. This study sought to evaluate whether trade-offs observed at both community and individual species levels could indicate adaptive fitness across an intensity of flooding intensity. The study was conducted at 25 sampling sites spanning approximately 600 km along the riparian zone in the Three Gorges Reservoir area, China. The findings revealed that, along the flooding gradient, the overall riparian community did not exhibit significant trade-offs between leaf and root traits. Examining three broadly distributed dominant species (Cynodon dactylon, Xanthium strumarium, and Abutilon theophrasti), perennial plants showed pronounced trade-offs under low flooding intensity, while annuals exhibited trade-offs under moderate and low flooding intensity. The trade-offs were evident in traits related to nitrogen-carbon resources, such as specific leaf area, root tissue density, and photosynthetic rate. However, under strong flooding intensity, the relationship between leaf and root traits of the species studied was decoupled. Furthermore, the study identified a significant correlation between soil nitrogen and the trade-off traits under moderate and low flooding intensity. Integrating results from the CSR (Competitors, Stress-tolerators, Ruderals) strategy model, species niche breath analysis, and nitrogen-regulated trade-off, the study revealed that, in the face of high flooding intensity, perennial species (C. dactylon) adopts an S-strategy, demonstrating tolerance through a conservative resource allocation that decouples leaf-root coordination. Annual species (X. strumarium and A. theophrasti), on the other hand, exhibit niche specialization along the flooding gradient, employing distinct strategies (R- and C-strategy). As flooding stress diminishes and soil nitrogen level decreases, plant strategies tend to shift towards an R-strategy with a competition for reduced N resources. In conclusion, the study highlighted the pivotal roles of soil nitrogen and flooding intensity acting as the dual determinants of species growth and tolerance. These dynamics of growth-tolerance balance were evident in the diverse trade-offs between leaf and root traits of individual plant species with different life histories, underscoring the array of adaptive strategies employed by riparian plants across the flooding intensity gradient.

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