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1.
Proc Natl Acad Sci U S A ; 121(17): e2314353121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38635634

RESUMO

Auxin regulates plant growth and development through downstream signaling pathways, including the best-known SCFTIR1/AFB-Aux/IAA-ARF pathway and several other less characterized "noncanonical" pathways. Recently, one SCFTIR1/AFB-independent noncanonical pathway, mediated by Transmembrane Kinase 1 (TMK1), was discovered through the analyses of its functions in Arabidopsis apical hook development. Asymmetric accumulation of auxin on the concave side of the apical hook triggers DAR1-catalyzed release of the C-terminal of TMK1, which migrates into the nucleus, where it phosphorylates and stabilizes IAA32/34 to inhibit cell elongation, which is essential for full apical hook formation. However, the molecular factors mediating IAA32/34 degradation have not been identified. Here, we show that proteins in the CYTOKININ INDUCED ROOT WAVING 1 (CKRW1)/WAVY GROWTH 3 (WAV3) subfamily act as E3 ubiquitin ligases to target IAA32/34 for ubiquitination and degradation, which is inhibited by TMK1c-mediated phosphorylation. This antagonistic interaction between TMK1c and CKRW1/WAV3 subfamily E3 ubiquitin ligases regulates IAA32/34 levels to control differential cell elongation along opposite sides of the apical hook.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Transdução de Sinais , Ubiquitinas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas F-Box/genética , Proteínas F-Box/metabolismo
2.
Chemistry ; 29(34): e202301048, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37022345

RESUMO

Tetrathiafulvalene (TTF) and Ni-bis(dithiolene) are typical conductive units widely studied in electronics, optics, and photochemistry. However, their applications in near-infrared (NIR) photothermal conversion are often limited by insufficient NIR absorption and low chemical/thermal stability. Herein, we integrate TTF and Ni-bis(dithiolene) into a covalent organic framework (COF) with stable and efficient NIR and solar photothermal conversion performance. Two isostructural COFs, namely Ni-TTF and TTF-TTF, are successfully isolated which are composed of TTF and Ni-bis(dithiolene) units as donor-acceptor (D-A) pairs or TTF units only. Both COFs show high BET surface areas and good chemical/thermal stability. Notably, compared with TTF-TTF, the periodic D-A arrangement in Ni-TTF significantly lowers the bandgap, leading to unprecedented NIR and solar photothermal conversion performance.

3.
Zhongguo Zhong Yao Za Zhi ; 47(22): 5965-5977, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36471922

RESUMO

The blood-brain barrier(BBB), a protective barrier between brain tissues and brain capillaries, can prevent drugs from entering the brain tissues to exert the effect, which greatly increases the difficulty in treating brain diseases. The drug delivery system across the BBB can allow efficient drug delivery across the BBB by virtue of carriers and formulations, thereby enhancing the therapeutic effect of drugs on brain tissue diseases. Liposomes and micelles have been extensively studied with advances in the targeted therapy across the BBB for the brain due to their unique structures and drug delivery advantages. This study summarized the research status of liposome and micelle drug delivery systems across the BBB based on the literature in recent years and analyzed their application advantages and mechanism in terms of trans-BBB capability, targeting, and safety. Moreover, the problems and possible countermeasures in the research on trans-BBB liposomes and micelles were discussed according to the current clinical translation, which may provide refe-rences and ideas for the development of trans-BBB targeted nano-drugs.


Assuntos
Barreira Hematoencefálica , Encefalopatias , Humanos , Lipossomos , Micelas , Sistemas de Liberação de Medicamentos , Transporte Biológico , Encéfalo
4.
Huan Jing Ke Xue ; 43(8): 4118-4126, 2022 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-35971709

RESUMO

Nitrous oxide (N2O) is one of the six greenhouse gases stipulated in the Kyoto Protocol. Its greenhouse potential over the past century was 298 times that of CO2, and the concentration of atmospheric N2O has been continuously and rapidly increasing during the past hundred years. Shallow lakes are an important source of atmospheric N2O. In order to explore the temporal and spatial changes and potential driving factors of N2O emissions from eutrophic water, we conducted field observations in February (winter) and August (summer) in Lake Taihu. We used the coefficient of diffusion-headspace bottle method to trace the variability in the N2O concentration[c(N2O)] and efflux[F(N2O)] from surface water bodies and explored the potential driving factors of N2O emissions. The optical measurements of dissolved organic matter (DOM) are an effective approach for tracing the source and composition of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). The migration and transformation processes of DOM also release a large amount of inorganic nitrogen, which changes the redox potential of the water column and thereby affects N2O emissions. Our results showed that the variability in c(N2O) and F(N2O) in the surface waters of Lake Taihu were strongly affected by water temperature and nutrient levels. The average c(N2O) of the surface waters was (19.7±2.7) nmol·L-1, corresponding to a mean F(N2O) of (41.1±1.8) µmol·(m2·d)-1, and the means of both c(N2O) and F(N2O) were higher in summer than those in winter (t-test, P<0.01). The input and accumulation of DOM could increase the production and emission potential of N2O in water bodies, as supported by both c(N2O) and F(N2O) significantly increasing with increasing level of terrestrial humic-like C1. The integration ratio of peak C to peak T IC:IT of DOM and the spectral slope S275-295 results indicated that there were high inputs of terrestrial DOM in the northwestern inflowing river mouths, concurring with the high production and emission of N2O found there. This suggested that the accumulation and degradation of terrestrial DOM potentially fueled the emission of N2O. Our results showed that water temperature, DOM composition, and nutrient level were all important factors affecting N2O emission from Lake Taihu. Long-term continuous observation can be applied to better evaluate the impact of various environmental factors on the production and emission of N2O in water bodies and to help with providing scientific emission reduction plans.


Assuntos
Lagos , Óxido Nitroso , China , Óxido Nitroso/análise , Rios , Estações do Ano , Água
5.
BMC Med Genomics ; 15(1): 144, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35765053

RESUMO

BACKGROUND: Methamphetamine (METH) abuse causes serious health problems, including injury to the immune system, leading to increased incidence of infections and even making withdrawal more difficult. Of course, immune cells, an important part of the immune system, are also injured in methamphetamine abuse. However, due to different research models and the lack of bioinformatics, the mechanism of METH injury to immune cells has not been clarified. METHODS: We examined the response of three common immune cell lines, namely Jurkat, NK-92 and THP-1 cell lines, to methamphetamine by cell viability and apoptosis assay in vitro, and examined their response patterns at the mRNA level by RNA-sequencing. Differential expression analysis of two conditions (control and METH treatment) in three types of immune cells was performed using the DESeq2 R package (1.20.0). And some of the differentially expressed genes were verified by qPCR. We performed Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of differentially expressed genes by the clusterProfiler R package (3.14.3). And gene enrichment analysis was also performed using MetaScape ( www.metascape.org ). RESULTS: The viability of the three immune cells was differentially affected by methamphetamine, and the rate of NK-cell apoptosis was significantly increased. At the mRNA level, we found disorders of cholesterol metabolism in Jurkat cells, activation of ERK1 and ERK2 cascade in NK-92 cells, and disruption of calcium transport channels in THP-1 cells. In addition, all three cells showed changes in the phospholipid metabolic process. CONCLUSIONS: The results suggest that both innate and adaptive immune cells are affected by METH abuse, and there may be commonalities between different immune cells at the transcriptome level. These results provide new insights into the potential effects by which METH injures the immune cells.


Assuntos
Metanfetamina , Ontologia Genética , Humanos , Metanfetamina/efeitos adversos , RNA Mensageiro/genética , Análise de Sequência de RNA , Transcriptoma
6.
Comput Struct Biotechnol J ; 20: 2442-2454, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35602976

RESUMO

Cathepsin L (CTSL), a cysteine protease that can cleave and activate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, could be a promising therapeutic target for coronavirus disease 2019 (COVID-19). However, there is still no clinically available CTSL inhibitor that can be used. Here, we applied Chemprop, a newly trained directed-message passing deep neural network approach, to identify small molecules and FDA-approved drugs that can block CTSL activity to expand the discovery of CTSL inhibitors for drug development and repurposing for COVID-19. We found 5 molecules (Mg-132, Z-FA-FMK, leupeptin hemisulfate, Mg-101 and calpeptin) that were able to significantly inhibit the activity of CTSL in the nanomolar range and inhibit the infection of both pseudotype and live SARS-CoV-2. Notably, we discovered that daptomycin, an FDA-approved antibiotic, has a prominent CTSL inhibitory effect and can inhibit SARS-CoV-2 pseudovirus infection. Further, molecular docking calculation showed stable and robust binding of these compounds with CTSL. In conclusion, this study suggested for the first time that Chemprop is ideally suited to predict additional inhibitors of enzymes and revealed the noteworthy strategy for screening novel molecules and drugs for the treatment of COVID-19 and other diseases with unmet needs.

7.
Huan Jing Ke Xue ; 43(4): 1958-1965, 2022 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-35393819

RESUMO

Lakes play an important role in the biogeochemical cycling of dissolved organic matter (DOM) and the emission of methane (CH4). We investigated the concentration and effluxes of CH4 and then analyzed the corresponding driving factors in Lake Luoma, a key lake along the South-to-North Water Transfer Project. Our results indicated that Lake Luoma was a hotspot of CH4 emissions with an annual mean concentration and efflux of (0.12±0.09) µmol·L-1 and (21.0±18.5) mmol·(m2·d)-1, respectively. We found higher mean CH4 levels in the wet season than those in the dry season and further higher levels than those in the wet-to-dry transition season. Spatially, the CH4 efflux was higher in the northwest inflowing regions and lower in the southeast outflow regions. The variability in annual CH4 efflux was affected by a combination of water temperature and hydrological conditions. Terrestrial input of dissolved organic carbon (DOC) and chromophoric DOM (CDOM) had fueled the production of CH4 by providing necessary carbon substrates, and four PARAFAC DOM components were identified including a microbial humic-like C1, a tryptophan-like C2, a terrestrial humic-like C3, and a tyrosine-like C4. The CH4 efflux from the lake was significantly promoted by the input and accumulation of terrestrial humic-like components, and Chl-a had no correlation with CH4 efflux, suggesting that algal degradation was not directly fueling the emission of CH4. Lake Luoma had been significantly disturbed by human activities, and terrestrial input of nutrient loading (TN and TP) into the lake not only improved the productivity and trophic level of the water body but also enhanced the production and release of CH4 from the surface water. We concluded that the CH4 emissions in Lake Luoma can be influenced by the combination of environmental factors, CDOM composition, and nutrient level. Long-term observation is needed for better evaluation of the driving factors in fueling the emission of CH4 so as to effectively reduce the emissions of CH4 and other greenhouse gases by taking corresponding countermeasures.


Assuntos
Lagos , Metano , Matéria Orgânica Dissolvida , Humanos , Lagos/química , Espectrometria de Fluorescência , Água
8.
Adv Mater ; 34(23): e2201716, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35435291

RESUMO

Aqueous Zn-iodine (Zn-I2 ) batteries have been regarded as a promising energy-storage system owing to their high energy/power density, safety, and cost-effectiveness. However, the polyiodide shuttling results in serious active mass loss and Zn corrosion, which limits the cycling life of Zn-I2 batteries. Inspired by the chromogenic reaction between starch and iodine, a structure confinement strategy is proposed to suppress polyiodide shuttling in Zn-I2 batteries by hiring starch, due to its unique double-helix structure. In situ Raman spectroscopy demonstrates an I5 - -dominated I- /I2 conversion mechanism when using starch. The I5 - presents a much stronger bonding with starch than I3 - , inhibiting the polyiodide shuttling in Zn-I2 batteries, which is confirmed by in situ ultraviolet-visible spectra. Consequently, a highly reversible Zn-I2 battery with high Coulombic efficiency (≈100% at 0.2 A g-1 ) and ultralong cycling stability (>50 000 cycles) is realized. Simultaneously, the Zn corrosion triggered by polyiodide is effectively inhibited owing to the desirable shuttling-suppression by the starch, as evidenced by X-ray photoelectron spectroscopy analysis. This work provides a new understanding of the failure mechanism of Zn-I2 batteries and proposes a cheap but effective strategy to realize high-cyclability Zn-I2 batteries.

9.
Inorg Chem ; 61(7): 3078-3085, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35142506

RESUMO

Metal-organic frameworks (MOFs) provide broad prospects for the development of new photothermal conversion materials, while their design and synthesis remain challenging. A new Zn-MOF (1) containing both tetrathiafulvalene (TTF) as an electron donor and naphthalene diimide (NDI) as an electron acceptor was constructed by using a space limiting effect. The material exhibited wide absorption peaks in the near-infrared region, indicating that there was strong charge transfer interaction between the TTF and NDI units and providing the possibility of photothermal conversion. 1 shows efficient near-infrared photothermal conversion performance. Under 808 nm laser (0.4 W cm-2) illumination, the temperature of 1 increased rapidly from room temperature to 250 °C, with good thermal stability and cycle durability. This work provides an efficient strategy for promising materials in photothermal therapy.

10.
Chem Commun (Camb) ; 58(15): 2488-2491, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35084422

RESUMO

We synthesized Cu single atoms embedded in a N-doped porous carbon catalyst with a high Faradaic efficiency of 93.5% at -0.50 V (vs. RHE) for CO2 reduction to CO. The evolution of Cu single-atom sites to nanoclusters of about 1 nm was observed after CO2 reduction at a potential lower than -0.30 V (vs. RHE). The DFT calculation indicates that Cu nanoclusters improve the CO2 activation and the adsorption of intermediate *COOH, thus exhibiting higher catalytic activity than CuNx sites. The structural instability observed in this study helps in understanding the actual active sites of Cu single atom catalysts for CO2 reduction.

11.
Huan Jing Ke Xue ; 43(2): 826-836, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35075856

RESUMO

Lake Qinghai is the largest lake in China and is of great significance to maintain the ecological security of the Qinghai-Tibet Plateau. Few studies have been carried out to investigate the optical composition and source of chromophoric dissolved organic matter (CDOM) in large lakes on the Qinghai-Tibet Plateau. It is of great significance to study the source and optical dynamics of CDOM in Lake Qinghai watershed for water quality protection and filling in the gaps in the knowledge of CDOM variability in a remote area. Two sampling campaigns in the Lake Qinghai watershed were carried out, and excitation-emission matrices coupled with parallel factor analysis (EEMs-PARAFAC) were used to unravel the optical composition and the sources of CDOM. Our results indicated that the mean dissolved organic carbon (DOC) concentration, a250:a365, and the spectral slope of CDOM absorption S275-295 in the lake were significantly higher than that in the inflow river (P<0.0001, t-test), whereas the mean absorption coefficient of CDOM a350, humification index (HIX), fluorescence peak integration ratio IC:IT, and specific ultraviolet absorbance at 254 nm SUVA254 of CDOM were shown to be lower in the lake than in the inflow river (P<0.0001), indicating that compared with the lake itself, CDOM in the inflow was humic-rich and highly aromatic. Four fluorescent components were obtained using PARAFAC, including a terrestrial human-like component C1, a microbial human-like component C2, a tyrosine-like C3, and a tryptophan-like C4. The mean DOC concentration, S275-295, and a250:a365in the headwater streams of the Lake Qinghai watershed were lower than those in the downstream estuary, indicating that the CDOM abundance increased, and the molecular weight decreased, from the headwaters to the downstream river mouths. The mean of SUVA254, C1, and the first axis of principal component analysis were positively related to terrestrial input (i.e., the PC1 values were significantly higher in rivers than in lakes (P<0.001)), indicating that the aromaticity of CDOM in rivers was higher than that in lakes. Particularly, the contribution of terrestrial humic-like C1 was higher in the Quanji River, Shaliu River, and Khargai River compared with that in other tributaries due to an intensified cultivated land use at the downstream estuary of these rivers.


Assuntos
Matéria Orgânica Dissolvida , Lagos , China , Humanos , Rios , Espectrometria de Fluorescência , Qualidade da Água
12.
Huan Jing Ke Xue ; 43(2): 837-846, 2022 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-35075857

RESUMO

Lake Poyang has significant differences in hydrological characteristics between the flood and dry seasons. Unraveling the optical composition, bioavailability, fate, and balance of chromophoric dissolved organic matter (CDOM) and organic carbon fluxes in Lake Poyang under different hydrological conditions can help provide advanced schemes on carbon cycling, the transfer and transformation of organic matter, and water resource management of the lake. Three fluorescent components, including a humic-like (C1), a tryptophan-like (C2), and a tyrosine-like (C3) component, were obtained using three-dimensional fluorescence spectroscopy coupled with parallel factor analysis. Prior to and after 28 days of laboratory biodegradation, the means of a254 and the terrestrial humic-like (C1) component in the flood season were both significantly higher than that in the dry season (t-test, P<0.01), indicating that the terrestrial humic-like (C1) component contributed importantly to the CDOM pool. The contribution percentages of protein-like components in the dry season were 81.7% of the summed fluorescent components of CDOM, indicating that there might be discharge of domestic wastewater from areas surrounding the lake in the dry season. The bioavailabilities of the humic-like (C1) component and DOC were 14.0% and 43.2%, respectively, in the dry season. This can be explained by a declined-dilution effect in the lake during the dry rather than in the flood season. We observed no significant difference in the bioavailability of protein-like components under different hydrological conditions. The bioavailability of C1 (i.e.,%ΔC1) showed a decreasing trend from the southern inflowing river mouths to the downstream northern outlet at Hukou in both the flood and dry seasons, indicating that the bioavailability of the C1 decreased following the migration of CDOM in the lake. In the dry season and flood season, Lake Poyang was the source of DOC with fluxes of 14.0×103 t·mon-1 and 1.4×103 t·mon-1, respectively, whereas CDOM fluxes in corresponding periods were the source and weak sink with corresponding fluxes of 9.3×1010 m3·(m·mon)-1 and 1.1×1010 m3·(m·mon)-1, respectively. Therefore, the lake released substantial organic matter to the downstream receiving waters during the dry season, whereas in the flood season, the higher water level in the Yangtze River resulted in a prolonged water residence time of the lake, and a fraction of CDOM was bio-degraded into inorganic nutrients, favoring the metabolisms and the eutrophication process of the lake ecosystem.


Assuntos
Matéria Orgânica Dissolvida , Lagos , Disponibilidade Biológica , China , Ecossistema , Rios , Espectrometria de Fluorescência
13.
World J Clin Cases ; 9(24): 7043-7052, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34540959

RESUMO

BACKGROUND: Patients' knowledge about the characteristics of their own cancer could be an important factor for understanding treatment regimens and adhering to therapies. However, to date nothing is known about the awareness among Chinese breast cancer patients about the characteristics of their own tumors. AIM: To investigate how much knowledge that Chinese breast cancer patients have about their tumor characteristics and the impact of health and education literacy on the acquisition of such information. METHODS: The survey was administered to patients who were diagnosed with breast cancer from 2017 to 2019 in three hospitals in China, and who came in for regular follow-up on an outpatient basis. We collected responses from 226 respondents who were asked about their cancer characteristics (stage, grade, and estrogen receptor status and human epidermal growth factor receptor 2 status of the cancer), and evaluated the correctness by comparing with their medical records. Logistic regression was used to assess the probability of knowing and of correctly answering questions. We also analyzed the association between our findings and the level of the patient's education and their health literacy. RESULTS: Overall, 20.80% to 57.96% of the patients reported knowing about the characteristics of breast cancer; of these, 10.18% to 46.46% reported these characteristics correctly. Education, age, and health literacy were all significantly associated with awareness rate, and with the level to which this information was accurate. CONCLUSION: Breast cancer patients in China know little about their disease, and better education aimed at improving their knowledge about cancer characteristics is urgently needed. The low level of awareness could represent a deficiency of communication between surgeons and patients, which may be one of the reasons why medical disputes occur in China.

14.
Huan Jing Ke Xue ; 42(8): 3719-3729, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309258

RESUMO

In the past few decades, China's rapid industrial activities and urbanization processes have greatly impacted the urban surface water ecosystem. The changes in the quality of urban surface water directly affect the supply and carbon cycling of urban waters. We collected 50 water samples from urban rivers, lakes, and reservoirs in the city of Changchun in June 2020. Three-dimensional fluorescence spectroscopy coupled with parallel factor analysis (EEMs-PARAFAC) was used to unravel the optical characteristics, composition, and sources of chromophoric dissolved organic matter (CDOM). Our results indicated that the mean concentration of DOC is significantly higher in urban rivers than in reservoirs (t-test, P<0.05), and the mean UV absorption coefficient of CDOM a254 of urban rivers is significantly larger than that of park lakes and reservoirs (t-test, P<0.05), indicating that urban rivers have the highest concentration of CDOM. The spectral slope of CDOM absorption S275-295 and the spectral slope ratio SR were shown to be higher in park lakes than in reservoirs, and even higher than in urban rivers (t-test, P<0.001). Three fluorescent components were obtained using PARAFAC, namely terrestrial human-like (C1), microbial human-like (C2) and tryptophan-like (C3) components. The mean fluorescence intensity of C1-C3 was significantly higher in urban rivers than in both the park lakes and reservoirs (t-test, P<0.005), and the mean fluorescence intensity of C1 in the reservoir water body was significantly higher than that of C2 and C3 (t-test, P<0.005), indicating that the discharge of municipal wastewater likely contributes significantly to the CDOM pool of urban rivers in Changchun, and the contribution percentages of highly bio-labile protein-like components to the CDOM pool in these waters are high. Urban wastewater treatment should be strengthened to effectively protect water quality, as well as the economic, environmental, and ecological functions of urban waters in Changchun City.


Assuntos
Ecossistema , Rios , China , Humanos , Lagos , Espectrometria de Fluorescência , Qualidade da Água
15.
World J Clin Cases ; 9(16): 4052-4062, 2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34141766

RESUMO

BACKGROUND: Mammary analogue secretory carcinoma (MASC) is a rare low-grade malignant salivary gland tumor. The morphological and immunohistochemical features of MASC closely resemble those of breast secretory carcinoma. The key characteristics of the lesion are a lack of pain and slow growth. There is no obvious specificity in the clinical manifestations and imaging features. The diagnosis of the disease mainly depends on the detection of the MASC-specific ETV6-NTRK3 fusion gene. CASE SUMMARY: This report describes a rare case of a 32-year-old male patient who presented with a gradually growing lesion that was initially diagnosed as breast-like secretory carcinoma of the right parotid gland. Imaging and histological investigations were used to overcome the diagnostic difficulties. The lesion was managed with right parotidectomy, facial nerve preservation, biological patch implantation to restore the resulting defect, and postoperative radiotherapy. On postoperative follow-up, the patient reported a mild facial deformity with no complications, signs of facial paralysis, or Frey's syndrome. CONCLUSION: The imaging and histological diagnostic challenges for MASC are discussed.

16.
Inorg Chem ; 60(11): 8331-8338, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34038101

RESUMO

Controlled hydration leads to four derivatives of a metal-organic framework consisting of cadmium ions, N1,N1,N4,N4-tetrakis(4-(pyridin-4-yl)phenyl)benzene-1,4-diamine, and coordinated and free nitrates. The balance of water coordination and the multitude of bonding of the weakly coordinated nitrate lead to a progressive change in the coordination number of the Cd2+ ions from eight to seven to six without great perturbation to the 4-fold interpenetration three-dimensional framework.

17.
Chemistry ; 27(43): 11050-11055, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33988893

RESUMO

Metal-organic frameworks (MOFs), as a class of new inorganic-organic hybrid crystal materials, could have important applications in near-infrared (NIR) photothermal conversion. Herein, a new charge-transfer MOF (Co-MOF) with mixed ligands of H4 TTFTB and bpmNDI incorporating redox-active tetrathiafulvalene/naphthalene diimide (TTF/NDI) units into one system is reported. Due to the presence of TTF/NDI oxidative and reductive couples, stable radicals can be observed in the MOF. In addition, charge transfer from the electron donor (TTF) to the acceptor (NDI) results in a broad absorption in the NIR region. The Co-MOF exhibited an efficient photothermal effect induced by irradiation with a NIR laser. Under the 808 nm laser (0.7 W cm-2 ) illumination, the temperature of the Co-MOF increased from room temperature to 201 °C in only 10 s. Furthermore, a series of polydimethylsiloxane (PDMS) films doped with trace amounts of Co-MOF showed efficient NIR photothermal conversion. When a Co-MOF@PDMS (0.6 wt %) film is irradiated by 808 nm laser with power of 0.5 W cm-2 , it's temperature can reach a plateau at 62 °C from 20 °C within 100 s. Our experimental results from the Co-MOF@PDMS film demonstrate that the effectiveness and feasibility of the material is promising for photothermal applications.

18.
J Craniofac Surg ; 32(2): e167-e171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33705062

RESUMO

ABSTRACT: The calcifying epithelial odontogenic tumor (CEOT) is a rare benign odontogenic tumor, which usually presents with distension of affected tissues. Radiologically, the lesions are often associated with an unerupted tooth and may have spot calcification shadows. The authors report a case of a CEOT in a 48-year-old male involving the right mandibular jaw bone and mentum soft tissues. The authors performed hemimandibulectomy and enucleation followed by reconstruction of the mandible using a vascularized free fibular flap through a digital surgical technique in order to restore the patient's facial symmetry and prepare the area for functional restorations. The case illustrates who the free fibular flap graft can be used for satisfactory mandibular reconstruction and restoration of the morphology and functions.


Assuntos
Retalhos de Tecido Biológico , Neoplasias Mandibulares , Reconstrução Mandibular , Tumores Odontogênicos , Neoplasias Cutâneas , Fíbula/cirurgia , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Pessoa de Meia-Idade , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia
19.
Inflammation ; 44(3): 846-858, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33140204

RESUMO

Periodontitis is a chronic inflammatory disease induced by Porphyromonas gingivalis (P. gingivalis) and other pathogens. P. gingivalis release various virulence factors including lipopolysaccharide (LPS). However, whether P. gingivalis-LPS inducing pyroptosis in human gingival fibroblasts (HGFs) remains unknown. In present study, P. gingivalis-LPS decreased the membrane integrity of HGFs, and pyroptosis-associated cytokines were upregulated at the mRNA level. In addition, pyroptosis proteins were highly expressed in gingival tissues of periodontitis. P. gingivalis-LPS induced gingivitis in the rat model, and the expression level of pyroptosis-associated proteins increased. Together, P. gingivalis-LPS can activate the pyroptosis reaction, which may be a pro-pyroptosis status in a relative low concentration.


Assuntos
Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Gengivite/induzido quimicamente , Lipopolissacarídeos/toxicidade , Porphyromonas gingivalis/metabolismo , Piroptose/efeitos dos fármacos , Animais , Caspase 1/metabolismo , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Gengiva/metabolismo , Gengiva/patologia , Gengivite/metabolismo , Gengivite/patologia , Humanos , Lipopolissacarídeos/isolamento & purificação , Masculino , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para Cima
20.
Angew Chem Int Ed Engl ; 59(50): 22397-22402, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32893447

RESUMO

Driven by the persisting poor understanding of the sluggish kinetics of the hydrogen evolution reaction (HER) on Pt in alkaline media, a direct correlation of the interfacial water structure and activity is still yet to be established. Herein, using Pt and Pt-Ni nanoparticles we first demonstrate a strong dependence of the proton donor structure on the HER activity and pH. The structure of the first layer changes from the proton acceptors to the donors with increasing pH. In the base, the reactivity of the interfacial water varied its structure, and the activation energies of water dissociation increased in the sequence: the dangling O-H bonds < the trihedrally coordinated water < the tetrahedrally coordinated water. Moreover, optimizing the adsorption of H and OH intermediates can re-orientate the interfacial water molecules with their H atoms pointing towards the electrode surface, thereby enhancing the kinetics of HER. Our results clarified the dynamic role of the water structure at the electrode-electrolyte interface during HER and the design of highly efficient HER catalysts.

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