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1.
Inorg Chem ; 61(16): 6026-6036, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394279

RESUMEN

Unlike isolable tin(II) hydrides supported by bulky ligands reported in the literature, this research describes the synthesis and characterization of thermally stable tin(II) hydrides LPhSnH (1-H) and MeLSnH (2-H) stabilized by sterically undemanding N,N,N-coordinating pincer-type ligands (LPh = 2,5-dipyridyl-3,4-diphenylpyrrolato; MeL = 2,5-bis(6-methylpyridyl)pyrrolato). The results from previous reports reveal that attempts to access tin(II) hydrides containing less-bulky ligands have had limited success, and decomposition to tin(I) distannynes often occurs. The key to the successful isolation of 1-H and 2-H is the identification of the role of Lewis acidic BsBu3, generated upon delivering hydride from commonly used hydride reagents M[BsBu3H] ("selectrides", M = Li or K). This study details compelling experimental evidence and theoretical results of the role played by BsBu3, which catalyzes the dehydrocoupling reactions of 1-H and 2-H to yield tin(I) distannynes LPhSn-SnLPh (12) and MeLSn-SnMeL (22) with the liberation of H2. To avoid the interference of BsBu3, 1-H and 2-H can be isolated in pure forms using pinacolborane as the hydride donor with LPhSnOMe (1-OMe) and MeLSnOMe (2-OMe) as reactants, respectively. DFT calculations and experimental observations indicate that the coordination of the Sn-H bond of 1-H to BsBu3 leaves an electrophilic tin center, rendering the nucleophilic attack by the second equivalent of 1-H forming a Sn-Sn bond.

2.
Exp Dermatol ; 26(4): 359-367, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27783430

RESUMEN

MicroRNAs (miRNAs) are small non-coding RNA molecules, which function in RNA silencing and post-transcriptional regulation of gene expression. Psoriasis is an inflammatory skin disease characterized by the dysfunction of keratinocytes, with the immune dysregulation. We reviewed the recent studies on the roles of miRNAs in psoriasis and showed that miRNAs play key roles in psoriasis, including the regulation of hyperproliferation, cytokine and chemokine production in keratinocyte, as well as mediating immune dysfunction in psoriasis. Furthermore, miRNAs, particularly, circulating miRNAs may serve as novel biomarkers for diagnosis, monitoring therapy response and reflecting the disease severity. Thus, targeting specific miRNAs may be used to develop new therapeutic methods for psoriasis.


Asunto(s)
MicroARNs/genética , MicroARNs/inmunología , Psoriasis/genética , Psoriasis/inmunología , Biomarcadores/sangre , Proliferación Celular , Humanos , Inmunidad Celular , Queratinocitos/fisiología , MicroARNs/sangre , Terapia Molecular Dirigida , Psoriasis/sangre , Psoriasis/tratamiento farmacológico , Índice de Severidad de la Enfermedad
3.
Chempluschem ; : e202400382, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39255446

RESUMEN

We present the synthesis, structural characterization, and reactivity studies of a tetra-zinc complex supported by the bisphenoxymethanone ligands and its transformation into various di-zinc architectures. Our findings highlight the potential of these complexes in molecular recognition, supramolecular chemistry, and catalysis.

4.
Biomed Pharmacother ; 110: 265-274, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30513504

RESUMEN

The IL-17-producing CD4+ T cell and γδT cells play critical roles in the pathogenesis of psoriasis (PS). PSORI-CM02 is a representative herbal formula for the treatment for PS in South China. It was confirmed to improve PS without obvious side effects in the clinic. Here we sought to clarify whether and how PSORI-CM02 regulates T cell differentiation and functions in IMQ-induced psoriasis-like BALB/c mouse model. Mice pre-treated 3 days with PSORI-CM02 significantly alleviated skin inflammation, as reduced in PASI score and classic psoriatic characteristics in pathological sections. CD3 and CD4 positive T cells were also fewer in the skin lesions of PSORI-CM02 groups, comparing to control group. PSORI-CM02 also decreased pro-inflammatory IFNγ mRNA and IL-17 A mRNA, while increased IL-4 mRNA in mouse skin lesions. In skin draining lymph nodes (DLN), PSORI-CM02 reduced the ratio of γδT cells and inhibited their function of producing IL-17 A. Nevertheless PSORI-CM02 had no effects on the ratio of total TCRß+T cells and CD4 + T cells. But it regulated CD4 + T helper cells differentiation, and resulted in the decreasing percentage of IFNγ producing Th1 cells and IL-17 A producing Th17 cells, while increasing the ratio of IL-4 producing Th2 cells in DLN. Further data showed that PSORI-CM02 promote expression of Th2 specific transcript factor GATA3, but had no effects on T-bet and RORγ. Thus, we tentatively interpret that PSORI-CM02 impairs IMQ-induced psoriasis by promoting Th2 cell response targeting of GATA3.


Asunto(s)
Dermatitis/metabolismo , Medicamentos Herbarios Chinos/uso terapéutico , Factor de Transcripción GATA3/biosíntesis , Imiquimod/toxicidad , Mediadores de Inflamación/metabolismo , Células Th2/metabolismo , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antineoplásicos/toxicidad , Citocinas/antagonistas & inhibidores , Citocinas/metabolismo , Dermatitis/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Mediadores de Inflamación/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos BALB C , Células Th2/efectos de los fármacos
5.
Zhong Yao Cai ; 29(8): 846-9, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17076248

RESUMEN

OBJECTIVE: To study on the fingerprint of Gaoli ginseng Injection. METHODS: SPE was used to purify samples. HPLC with DAD detector was used to analysis the samples of Gaoli ginseng Injection. Then the analogical degree of the chromatography was estimated by the software. RESULTS: The fingerprints had 14 communal chromatsogram peaks, and the analogical degrees of all samples were greater than 0.95. CONCLUSION: The method is credible. It provides a scientific basis to control the quality of Gaoli ginseng Injection more effectively.


Asunto(s)
Medicamentos Herbarios Chinos/química , Panax/química , Plantas Medicinales/química , Cromatografía Líquida de Alta Presión/métodos , Estabilidad de Medicamentos , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/normas , Inyecciones , Control de Calidad , Reproducibilidad de los Resultados
6.
J Chromatogr A ; 1070(1-2): 35-42, 2005 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-15861785

RESUMEN

A novel, simple and accurate fingerprint method was developed using high-performance liquid chromatography-photodiode array detection (HPLC-DAD) for the quality control of Hypericum japonicum thunb (Tianjihuang), a Chinese herbal medicine used for the treatment of several bacterial diseases, infectious hepatitis, gastrointestinal disorder, internal hemorrhage and tumors. For the first time, the feasibility and advantages of employing chromatographic fingerprint were investigated and demonstrated for the evaluation of Tianjihuang by systematically comparing chromatograms with a professional analytical software recommended by State Food and Drug Administration (SFDA). Our results revealed that the chromatographic fingerprint combining similarity evaluation could efficiently identify and distinguish raw herbs of Tianjihuang from different sources. The effects resulted from collecting locations, harvesting time and storage time on herbal chromatographic fingerprints were also examined.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Hypericum/química , Espectrofotometría Ultravioleta/métodos , Cromatografía en Capa Delgada , Control de Calidad
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