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1.
Endocrine ; 84(1): 148-154, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37815746

ABSTRACT

PURPOSE: Sex hormones are thought to be responsible for the unique gender differences in papillary thyroid cancer(PTC). Most previous studies on these have focused on the expression of estrogen receptors, or have been limited to animal studies. The aim of our study was to explore the relationship between serum sex hormones and the pathological features of PTC in the clinical setting, as further evidence of the role of sex hormones in PTC. METHODS: Retrospective data analysis of patients who underwent thyroid surgery at the Department of Thyroid Surgery, Nanjing Drum Tower Hospital from January 2022 to September 2022 Correlation between serum sex hormone and pathological features was analyzed in male patients and in menopausal female patients. Serum sex hormones include luteinizing hormone(LH), follicle stimulating hormone(FSH), estradiol(E2), total testosterone(TT), progesterone(P), and prolactin(PRL). Tumor pathological characteristics include the number and size of tumor, presence of extrathyroidal extension(ETE), presence of lymph node metastasis(LNM). RESULTS: Preoperative serum E2 in male patients was positively correlated with tumor size in PTC, LH was negatively correlated with LNM, while TT and P were negatively correlated with ETE. Similar findings were not observed in menopausal female patients. CONCLUSION: We observed that serum sex hormones correlate with the pathological features of PTC in male patients, for the first time in a clinical study. High serum estrogens may be a risk factor for PTC, while androgens are the opposite. This somewhat corroborates previous research and provides new variables for future PTC prediction models.


Subject(s)
Carcinoma, Papillary , Thyroid Neoplasms , Humans , Male , Female , Thyroid Cancer, Papillary , Thyroid Neoplasms/pathology , Retrospective Studies , Carcinoma, Papillary/pathology , Gonadal Steroid Hormones , Prolactin
2.
Front Plant Sci ; 14: 1164866, 2023.
Article in English | MEDLINE | ID: mdl-37123833

ABSTRACT

Magnesium is an essential macronutrient for plant photosynthesis, and in response to Mg deficiency, dicots appear more sensitive than monocots. Under Mg deficiency, we investigated the causes of differing photosynthetic sensitivities in a dicot and a monocot species. Rice (Oryza sativa L.) and cucumber (Cucumis sativus L.) were grown in hydroponic culture to explore their physiological responses to Mg deficiency stress. Both Mg-deficient rice and cucumber plants exhibited lower biomass, leaf area, Mg concentration, and chlorophyll content (Chl) compared with Mg-sufficient plants. However, a more marked decline in Chl and carotenoid content (Car) occurred in cucumber. A lower CO2 concentration in chloroplasts (C c) was accompanied by a decrease in the maximum rate of electron transport (J max) and the maximum rate of ribulose 1,5-bisphosphate carboxylation (V cmax), restricting CO2 utilization in Mg-deficient plants. Rice and cucumber photorespiration rate (P r) increased under Mg deficiency. Additionally, for cucumber, Car and non-photochemical quenching (NPQ) were reduced under lower Mg supply. Meanwhile, cucumber Mg deficiency significantly increased the fraction of absorbed light energy dissipated by an additional quenching mechanism (Φf,D). Under Mg deficiency, suppressed photosynthesis was attributed to comprehensive restrictions of mesophyll conductance (g m), J max, and V cmax. Cucumber was more sensitive to Mg deficiency than rice due to lower NPQ, higher rates of electron transport to alternative pathways, and subsequently, photooxidation damage.

3.
PLoS One ; 18(4): e0285175, 2023.
Article in English | MEDLINE | ID: mdl-37104499

ABSTRACT

BACKGROUND: Public satisfaction is the ultimate goal and an important determinant of China's urban regeneration plan. This study is the first to use massive data to perform sentiment analysis of public comments on China's urban regeneration. METHODS: Public comments from social media, online forums, and government affairs platforms are analyzed by a combination of Natural Language Processing, Knowledge Enhanced Pre-Training, Word Cloud, and Latent Dirichlet Allocation. RESULTS: (1) Public sentiment tendency toward China's urban regeneration was generally positive but spatiotemporal divergences were observed; (2) Temporally, public sentiment was most negative in 2020, but most positive in 2021. It has remained consistently negative in 2022, particularly after February 2022; (3) Spatially, at the provincial level, Guangdong posted the most comments and Tibet, Shanghai, Guizhou, Chongqing, and Hong Kong are provinces with highly positive sentiment. At the national level, the east and south coastal, southwestern, and western China regions are more positive, as opposed to the northeast, central, and northwest regions; (4) Topics related to Shenzhen's renovations, development of China's urban regeneration and complaints from residents are validly categorized and become the public's key focus. Accordingly, governments should address spatiotemporal disparities and concerns of local residents for future development of urban regeneration.


Subject(s)
Sentiment Analysis , Social Media , Humans , China , Attitude , Regeneration , Hong Kong
5.
Sci Total Environ ; 700: 134421, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31693953

ABSTRACT

The elemental concentrations of both plants and soils are sensitive to variations in precipitation due to the limiting roles of water on soil processes and plant growth in karst ecosystems of Southwestern China; however, precipitation is predicted to increase in this region. Nevertheless, it is unclear how the elemental composition of soils and plants might respond to such increases in moisture. Particularly, how potassium (K) may behave as a key mediator in the regulation of the water potential of plants. For this study, the responses of the elemental composition of both soils and plants to the variable addition of water were investigated. Two grasses (Cymbopogon distans and Arundinella setosa) and two shrubs (Carissa spinarum and Bauhinia brachycarpa) were investigated under four levels of watering treatments 0%, +20%, +40%, and +60%, relative to the annual rainfall, respectively. Compared to the control (CK), the soil water content (SWC) increased to 3.75, 3.86, and 4.34 mg g-1 in T1, T2, and T3 groups, respectively (p < 0.05). Non-metal elements (C, H, N, S, and P, except for Si) in the soil were relatively stable with water addition; however, metal elements (Al, Na, Mg, Fe, and K, along with Si) increased significantly, whereas Zn and Ca decreased (p < 0.05). With water addition, leaf N and P remained unchanged in all four species, while K, Mg, and S decreased in both shrubs (higher C:K, N:K, and P:K). Increases in Fe, Si, and K were observed in both grasses (lower C:K, N:K, and P:K), which suggested that K played distinct roles for water regulation in shrubs and grasses. These findings implied that the elemental compositions of both soils and plants might be altered with increasing precipitation in the future, where different plant types may adopt distinct K-regulation strategies to cope with variable soil moisture.


Subject(s)
Ecosystem , Environmental Monitoring , Plants , Rain , China , Poaceae
6.
Cells ; 7(12)2018 Dec 11.
Article in English | MEDLINE | ID: mdl-30545006

ABSTRACT

Aquaporins (AQPs) are membrane channel proteins regulating the flux of water and other various small solutes across membranes. Significant progress has been made in understanding the roles of AQPs in plants' physiological processes, and now their activities in various plant⁻microbe interactions are receiving more attention. This review summarizes the various roles of different AQPs during interactions with microbes which have positive and negative consequences on the host plants. In positive plant⁻microbe interactions involving rhizobia, arbuscular mycorrhizae (AM), and plant growth-promoting rhizobacteria (PGPR), AQPs play important roles in nitrogen fixation, nutrient transport, improving water status, and increasing abiotic stress tolerance. For negative interactions resulting in pathogenesis, AQPs help plants resist infections by preventing pathogen ingress by influencing stomata opening and influencing defensive signaling pathways, especially through regulating systemic acquired resistance. Interactions with bacterial or viral pathogens can be directly perturbed through direct interaction of AQPs with harpins or replicase. However, whilst these observations indicate the importance of AQPs, further work is needed to develop a fuller mechanistic understanding of their functions.

7.
Chem Commun (Camb) ; 54(10): 1197-1200, 2018 Jan 31.
Article in English | MEDLINE | ID: mdl-29335705

ABSTRACT

An efficient synthesis of 2,5-disubstituted oxazoles via Co(iii) catalysis is described herein. The synthesis is achieved under mild conditions through [3+2] cycloaddition of N-pivaloyloxyamides and alkynes. The reaction operates through an internal oxidation pathway and features a very broad substrate scope. The one-step synthesis of natural products such as texamine and balsoxin has been demonstrated via this protocol.

8.
Org Lett ; 19(19): 5348-5351, 2017 10 06.
Article in English | MEDLINE | ID: mdl-28926268

ABSTRACT

Cobaltacycle synthesis via C-H activation has been achieved for the first time, providing key mechanistic insight into cobalt catalytic chemistry. N-Chloroamides are used as a directing synthon for cobalt-catalyzed room-temperature C-H activation and construction of heterocycles. Alkynes as coupling partners allow convenient access to isoquinolones, a class of synthetically and pharmaceutically important compounds. The broad substrate scope enables a diverse range of substitution patterns to be incorporated into the heterocyclic scaffold.

9.
Org Lett ; 19(16): 4359-4362, 2017 08 18.
Article in English | MEDLINE | ID: mdl-28777581

ABSTRACT

A C-H activation-based strategy has been developed for the synthesis of N-amino azaheterocycles. Rh(III)-catalyzed coupling of N-Boc hydrazones/N-Boc hydrazines with diazodiesters/diazoketoesters provides convenient access to synthetically and medicinally important compounds, N-amino isoquinolin-3-ones and N-amino indoles, by harnessing N-tert-butyloxycarbonyl (N-Boc) cleavage as an adaptable reactivity pattern in distinct synthetic scenarios.

10.
Angew Chem Int Ed Engl ; 56(19): 5222-5226, 2017 05 02.
Article in English | MEDLINE | ID: mdl-28378537

ABSTRACT

A relay formalism is proposed herein for categorizing the interplay among reactants, target product, and catalytic center in transition-metal catalysis, an important factor that can dictate overall catalysis viability and efficiency. In this formalism, transition-metal catalysis can proceed by dissociative relay, associative covalent relay, and associative dative relay modes. An intriguing associative covalent relay process operates in rhodium(III)-catalyzed oxadiazolone-directed alkenyl C-H coupling with alkynes and allows efficient access to primary pyridinylamines. Although the primary pyridinylamine synthesis mechanism is posteriori rationalized, the relay formalism formulated herein can provide an important mechanistic conceptual framework for future catalyst design and reaction development.

11.
Org Lett ; 19(9): 2418-2421, 2017 05 05.
Article in English | MEDLINE | ID: mdl-28425721

ABSTRACT

We report herein the development of a Co(III)-catalyzed enaminone-directed C-H amidation method for synthetic access to quinolones, an important heterocyclic scaffold for diverse pharmaceutically active structures. The C-H coupling with dioxazolones and subsequent deacylation of an installed amide group allow consecutive C-N coupling generation of quinolones with wide-ranging compatible substituent patterns.

12.
Org Lett ; 18(20): 5412-5415, 2016 Oct 21.
Article in English | MEDLINE | ID: mdl-27704852

ABSTRACT

Despite their tremendous synthetic and pharmaceutical utility, primary azaaromatic amines remain elusive for access based on a generally applicable C-H functionalization strategy. An oxadiazolone-enabled approach is reported for convenient entry into N-unsubstituted 1-aminoisoquinolines through Co(III)-catalyzed redox-neutral, step-, atom-, and purification-economic C-H functionalization with alkynes. A 15N labeling experiment reveals the effectiveness of both oxadiazolone N atoms as directing sites. The installed primary amine can be harnessed as a synthetically useful handle for attachment of divergent appendages.

13.
Org Lett ; 18(21): 5632-5635, 2016 11 04.
Article in English | MEDLINE | ID: mdl-27739295

ABSTRACT

Traceless heterocycle synthesis based on transition-metal-catalyzed C-H functionalization is synthetically appealing but has been realized only in monodentate directing systems. Bidentate directing systems allow for the achievement of high catalytic reactivity without the need for a high-cost privileged ligand. The first bidentate directing-enabled, traceless heterocycle synthesis is demonstrated in the cobalt-catalyzed synthesis of isoquinolines via 2-hydrazinylpyridine-directed C-H coupling/cyclization with alkynes. Convenient directing group installation through a ubiquitously present ketone group allows synthetic elaboration for complex molecules.

14.
Chemistry ; 22(41): 14508-12, 2016 Oct 04.
Article in English | MEDLINE | ID: mdl-27458711

ABSTRACT

A previously elusive Ru(II) -catalyzed N-N bond-based traceless C-H functionalization strategy is reported. An N-amino (i.e., hydrazine) group is used for the directed C-H functionalization with either an alkyne or an alkene, affording an indole derivative or olefination product. The synthesis features a broad substrate scope, superior atom and step economy, as well as mild reaction conditions.

15.
Org Lett ; 18(15): 3806-9, 2016 08 05.
Article in English | MEDLINE | ID: mdl-27434348

ABSTRACT

A Co(III)-catalyzed, internal and terminal alkyne-compatible indole synthesis protocol is reported herein. The N-amino (hydrazine) group imparts distinct, diverse reactivity patterns for directed C-H functionalization/cyclization reactions. Notable synthetic features include regioselectivity for a meta-substituted arylhydrazine, regioselectivity for a chain-branched terminal alkyne, formal incorporation of an acetylenic unit through C2-desilylation on a C2-silylated indole derivative, formal inversion of regioselectivity through consecutive C3-derivatization and C2-desilylation processes, and formal bond migration for a linear-chain terminal alkyne.

16.
Angew Chem Int Ed Engl ; 55(32): 9384-8, 2016 08 01.
Article in English | MEDLINE | ID: mdl-27305280

ABSTRACT

The use of enaminones as effective synthons for a directed C-H functionalization is reported. Proof-of-concept protocols have been developed for the Rh(III) -catalyzed synthesis of naphthalenes, based on the coupling of enaminones with either alkynes or α-diazo-ß-ketoesters. Two inherently reactive functionalities (hydroxy and aldehyde groups) are integrated into the newly formed cyclic framework and a broad range of substituents are tolerated, rendering target products readily available for further elaboration.

17.
Org Biomol Chem ; 14(21): 4848-52, 2016 Jun 07.
Article in English | MEDLINE | ID: mdl-27146107

ABSTRACT

Synthesis of isoquinolines based on efficient C-C and C-N bond formation through Rh(iii)-catalyzed C-H activation and subsequent intramolecular cyclization is reported. Diazodiesters serving as a C2 source in the newly formed heterocycles are first demonstrated. Additionally, the Rh(iii)-catalyzed direct C-H activation/cyclization of benzimidates with diazoketoesters is also described.

18.
Org Lett ; 18(9): 2062-5, 2016 05 06.
Article in English | MEDLINE | ID: mdl-27058735

ABSTRACT

An efficient double C-N bond formation sequence to prepare highly substituted quinazolines utilizing benzimidates and dioxazolones under the catalytic redox-neutral [Cp*RhCl2]2/AgBF4 system, where dioxazolones could work as an internal oxidant to maintain the catalytic cycle, is reported. N-Unsubstituted imine not only acts as a directing group but also functions as a nucleophile in postcoupling cyclization, and dioxazolone acts as a coupling partner for access to heterocycle.

19.
Org Lett ; 18(5): 1178-81, 2016 Mar 04.
Article in English | MEDLINE | ID: mdl-26909684

ABSTRACT

A distinct C-H activation-based traceless synthetic protocol via electrophilic removal of a directing group is reported, complementing the currently exclusively used nucleophilic strategy. Rh(III)-catalyzed, N-nitroso-directed C-H activation allows the development of a traceless, atom- and step-economic, cascade approach for the synthesis of indole skeletons, starting from readily available N-nitroso and α-diazo-ß-keto compounds. Importantly, the cyclization/denitrosation reaction represents a hitherto unobserved reactivity pattern for the N-nitroso group.

20.
J Hazard Mater ; 121(1-3): 175-81, 2005 May 20.
Article in English | MEDLINE | ID: mdl-15885419

ABSTRACT

The phenomenon of filtering particles by a fluidized bed is complex and the parameters that affect the control efficiency of filtration have not yet been clarified. The major objective of the study focuses on the effect of characteristics of ash and filter media on filtration efficiency in a fluidized bed. The performance of the fluidized bed for removal of particles in flue gas at various fluidized operating conditions, and then the mechanisms of collecting particles were studied. The evaluated parameters included (1) various ashes (coal ash and incinerator ash); (2) bed material size; (3) operating gas velocity; and (4) bed temperature. The results indicate that the removal efficiency of coal ash increases initially with gas velocity, then decreases gradually as velocity exceeds some specific value. Furthermore, the removal of coal ash enhance with silica sand size decreasing. When the fluidized bed is operated at high temperature, diffusion is a more important mechanism than at room temperature especially for small particles. Although the inertial impaction is the main collection mechanism, the "bounce off" effect when the particles collide with the bed material could reduce the removal efficiency significantly. Because of layer inversion in fluidized bed, the removal efficiency of incinerator ash is decreased with increasing of gas velocity.


Subject(s)
Carbon/chemistry , Filtration/instrumentation , Filtration/methods , Water Pollutants/isolation & purification , Water Pollution/prevention & control , Coal Ash , Incineration , Kinetics , Particle Size , Particulate Matter , Silicon Dioxide/chemistry , Temperature
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