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1.
Chemistry ; 30(58): e202402602, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39112402

RESUMEN

Mild and inexpensive copper-catalyzed aromatization-driven ring-opening amination and oxygenation of spiro dihydroquinazolinones are presented, respectively. These protocols provide facile and atom-economical access to the aminated and the carbonyl-containing quinazolin-4(3H)-ones in good yields with good functional group compatibility, which are difficult to obtain by conventional methods. Remarkably, a telescoped procedure involving the condensation and the ring-opening/functionalization for simple cycloalkanone was found to be accessible. Mechanistic studies suggest a radical pathway for this transformation.

2.
Mycopathologia ; 189(3): 35, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637433

RESUMEN

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.


Asunto(s)
Antifúngicos , Candidiasis , Humanos , Antifúngicos/farmacología , Candidiasis/microbiología , Candida auris , Candida , Anfotericina B/farmacología , Farmacorresistencia Fúngica/genética , Pruebas de Sensibilidad Microbiana
3.
Angew Chem Int Ed Engl ; : e202419082, 2024 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-39479975

RESUMEN

Because of the unique and superior optoelectronic properties, metal halide perovskites (MHPs) have attracted great interests in photocatalysis. Element doping strategy is adopted to modify perovskite materials to improve their photocatalytic performance. However, the contribution of bare doping-site onto photocatalytic efficiency, and the correlation between doping locations and activity have not yet to be demonstrated. This promoted us to explore the potential of A-site-doped MHPs for photocatalysis. Herein, we dope potassium (K+) into CsPbBr3 and first reveal that the occupied locations of K+ in CsPbBr3 is lattice incorporation rather than surface segregation, which would change from A-site substitution to interstitial site in lattice with the increase of K+ concentrations. Taking H2 evolution as a model reaction, photocatalytic activity of CsPbBr3 after K+ doping could be significantly improved ~11-fold with A-site substitution, which is superior to that of interstitial site doping. Moreover, other alkali metals including Li, Na, and Rb doping give the same results. The structure of photocatalysts during reaction confirmed the contribution of A-site doping onto enhanced photocatalytic activity. Mechanistic insights show it is a result of the relaxed residual lattice strain induced promoted charge-carriers dynamics and formed upward shifting of band after K+ A-site doping.

4.
J Org Chem ; 88(14): 9927-9940, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37432753

RESUMEN

An array of redox-neutral alkylation/cyclization cascade reactions of N-functionalized acrylamides with cycloalkyl hydroperoxides were achieved via the alkoxyl radical-triggered C-C bond cleavage. Through adjusting the radical acceptors on the N atom, a variety of keto-alkylated chain-containing azaheterocycles, including indolo[2,1-a]isoquinolin-6(5H)-ones, quinoline-2,4-diones, and pyrido[4,3,2-gh]phenanthridines were constructed by a one-pot procedure with good yields and excellent functional group tolerance.

5.
Org Biomol Chem ; 21(28): 5855-5860, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37401815

RESUMEN

An efficient iron-catalyzed alkoxyl radical-mediated C-C bond cleavage/phosphorothiolation cascade is presented. This protocol features mild and redox neutral conditions, wide substrate scope and easy scalability, allowing straightforward access to functionalized S-alkyl organophosphorus compounds in moderate to good yields.

6.
Sheng Li Xue Bao ; 74(3): 381-391, 2022 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-35770636

RESUMEN

Extracellular matrix (ECM) stiffness is closely related to the physiological and pathological states of breast tissue. The current study was aimed to investigate the effect of silk fibroin/collagen composite hydrogels with adjustable matrix stiffness on the growth and phenotype of normal breast epithelial cells. In this study, the enzymatic reaction of horseradish peroxidase (HRP) with hydrogen peroxide (H2O2) was used to change the degree of cross-linking of the silk fibroin solution. The rotational rheometer was used to characterize the composite hydrogel's biomechanical properties. Human normal mammary epithelial cell line MCF-10A were inoculated into composite hydrogels with various stiffness (19.10-4 932.36 Pa) to construct a three dimensional (3D) culture system of mammary epithelial cells. The CCK-8 assay was applied to detect the cell proliferation rate and active states in each group. Hematoxylin-Eosin (HE) staining and whole-mount magenta staining were used for histological evaluation of cell morphology and distribution. The results showed that with the increase of matrix stiffness, MCF-10A cells exhibited inhibited proliferation rate, decreased formation of acinus structures and increased branching structures. Meanwhile, with the increase of matrix stiffness, the polarity of MCF-10A cells was impeded. And the increase of matrix stiffness up-regulated the expression levels of mmp-2, mmp-3, and mmp-9 in MCF-10A cells. Among the genes related to epithelial-mesenchymal transition (EMT), the expression level of the epithelial marker gene E-cadherin was significantly down-regulated, while the interstitial cell marker gene Vimentin was up-regulated, and the expression levels of Snail, Wnt5b and Integrin ß1 in the Wnt pathway were up-regulated. These results suggest that the silk fibroin/collagen composite hydrogels with adjustable matrix stiffness regulates the proliferation and the phenotype of MCF-10A cells. The effects of increased matrix stiffness may be closely related to the changes of the polar structures and function of MCF-10A cells, as well as the occurrence of ECM-remodeling and EMT.


Asunto(s)
Fibroínas , Colágeno/metabolismo , Células Epiteliales/metabolismo , Fibroínas/química , Fibroínas/metabolismo , Fibroínas/farmacología , Humanos , Hidrogeles/química , Hidrogeles/metabolismo , Peróxido de Hidrógeno , Fenotipo
7.
Zhonghua Nan Ke Xue ; 28(6): 495-500, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-37477465

RESUMEN

OBJECTIVE: To study the illness cognition and related factors in patients with prostate cancer (PCa). METHODS: Using the convenience-sampling method, we selected 231 PCa patients treated in a general hospital in Xuzhou from October 2019 to October 2020. We conducted a cross-sectional study of the cases based on the general data of the patients and their scores on the Illness Cognition Questionnaire (ICQ). RESULTS: The PCa patients showed a high negative and a low positive illness cognition. The ICQ scores of the patients were high on "helplessness" (13.70 ± 3.54) and low on "acceptance" (16.64 ± 3.37) and "perceived benefits" (13.93 ± 3.76). Age, disease duration, disease stage and number of children were the four factors included in the regression equation of the participants' illness cognition. CONCLUSION: Negative illness cognition is high in PCa patients, higher in those at a younger age, with a longer disease duration, or with more than one child than in those at an older age, with a shorter disease duration, or with only one or no child.


Asunto(s)
Cognición , Neoplasias de la Próstata , Masculino , Humanos , Estudios Transversales , Encuestas y Cuestionarios
8.
J Org Chem ; 86(12): 8263-8273, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34107678

RESUMEN

A visible light-driven, copper-catalyzed aerobic oxidative cleavage of cycloalkanones has been presented. A variety of cycloalkanones with varying ring sizes and various α-substituents reacted well to give the distal keto acids or dicarboxylic acids with moderate to good yields.

9.
J Org Chem ; 86(17): 11987-11997, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34374284

RESUMEN

A cheap iron-catalyzed C-C bond cleavage/thiolation and selenylation of cycloalkyl hydroperoxides are presented. This redox-neutral protocol provides efficient access to diverse distal keto-functionalized thioethers and selenium compounds. Remarkably, only some amounts of disulfides are required for this transformation.


Asunto(s)
Peróxido de Hidrógeno , Hierro , Catálisis , Disulfuros , Sulfuros
10.
Zhongguo Zhong Yao Za Zhi ; 46(23): 6289-6293, 2021 Dec.
Artículo en Zh | MEDLINE | ID: mdl-34951256

RESUMEN

The ripe dried fruit of citron(Citrus medica) is one of the important sources of Chinese herb Citri Fructus. At the same time, it is also grown for edible and ornamental uses. There are many species and abundant genetic variation. To clarify the intraspecific variation and resource distribution of citron, this study investigated the variation in 11 citron fruits, basically covering the main species in China, including Xiaoguo citron(C. medica var. ethrog), Goucheng(C. medica var. yunnanensis), Muli citron(C.medica var. muliensis), Dehong citron(C.medica×Citrus spp.), Fuzhou citron(C.medica×C.grandis?), Mawu(C.medica×C.grandis?), Cangyuan citron, Binchuan citron, Sweet citron, Big citron, and Small citron. The natural communities of citron were proved to be mainly distributed in the southwestern and western Yunnan and southeastern Tibet of China, with Yunnan, Sichuan, Guangxi, Chongqing, Hubei, and Zhejiang identified as the main production areas. Citron has also been widely grown in India, the Mediterranean region, and the Caribbean coast countries. The field investigation revealed the large-scale intraspecific variation of citron fruits. Most of the fruits are oval-like or sphere-like in shape. The fruits are green when raw and yellow when ripe, with oil cell dots on the skin, stripe-likes running from top to bottom, and bulge at the top. Usually, in the smaller citron fruits, the pulp and juice vesicles are better developed and the central columella is tighter. By contrast, the juice vesicles and central columella in larger fruits became more vacant, with carpels visible, and the apex segregation and development of the carpels is one of the reasons for variation. These variations should be given top priority in the future variety selection and breeding, and the quality differences of different citron species and their mechanisms should be further studied. In particular, variety selection and classification management according to their medicinal or edible purposes will provide scientific and technological supports for the orderly, safe, and effective production of citron products consumed as food and medicine.


Asunto(s)
Citrus , Frutas , China , Gusto , Tibet
11.
J Cell Physiol ; 235(3): 2722-2737, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31508820

RESUMEN

Liver fibrosis (LF) is the result of a vicious cycle between inflammation-induced chronic hepatocyte injury and persistent activation of hepatic stellate cells (HSCs). Mesenchymal stem cell (MSC)-based therapy may represent a potential remedy for treatment of LF. However, the fate of transplanted MSCs in LF remains largely unknown. In the present study, the fate and antifibrotic effect of MSCs were explored in a LF model induced by CCl4 in mouse. Additionally, MSCs were stimulated in vitro with LF-associated factors, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and transforming growth factor-ß1 (TGF-ß1), to mimic the LF microenvironment. We unveiled that MSCs exhibited autophagy in response to the LF microenvironment through Becn1 upregulation both in vivo and in vitro. However, autophagy suppression induced by Becn1 knockdown in MSCs resulted in enhanced antifibrotic effects on LF. The improved antifibrotic potential of MSCs may be attributable to their inhibitory effects on T lymphocyte infiltration, HSCs proliferation, as well as production of TNF-α, IFN-γ, and TGF-ß1, which may be partially mediated by elevated paracrine secretion of PTGS2/PGE2 . Thus, autophagy manipulation in MSCs may be a novel strategy to promote their antifibrotic efficacy.


Asunto(s)
Autofagia/genética , Beclina-1/genética , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/terapia , Células Madre Mesenquimatosas/metabolismo , Animales , Beclina-1/biosíntesis , Tetracloruro de Carbono/toxicidad , Proliferación Celular , Células Cultivadas , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Hepatocitos/metabolismo , Interferón gamma/metabolismo , Masculino , Trasplante de Células Madre Mesenquimatosas , Ratones , Ratones Endogámicos C57BL , Interferencia de ARN , ARN Interferente Pequeño/genética , Linfocitos T/inmunología , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
12.
Chemistry ; 26(51): 11690-11694, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32557942

RESUMEN

A metal-free, visible-light-induced oxidative C-C bond cleavage of cycloketones with molecular oxygen is described. Cooperative Brønsted-acid catalysis and photocatalysis enabled selective C-C bond cleavage of cycloketones to generate an array of γ-, δ- and ϵ-keto esters under very mild conditions. Mechanistic studies indicate that singlet molecular oxygen (1 O2 ) is responsible for this transformation.

13.
J Org Chem ; 85(11): 7515-7525, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32345024

RESUMEN

A nickel-catalyzed Suzuki alkyl-aryl coupling of cycloalkyl silyl peroxides with boronic acids is reported. The primary and secondary ketoalkyl electrophiles generated through C-C bond cleavage were amenable, providing rapid access to a variety of distal arylated alkyl ketones. A radical pathway is proposed for this reaction.

14.
J Clin Microbiol ; 57(2)2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30463892

RESUMEN

A total of 133 clinical Trichosporon isolates were collected in the National China Hospital Invasive Fungal Surveillance Net (CHIF-NET) program in 2009 to 2016. Accurate identification was performed by sequencing of the intergenic spacer 1 (IGS1) region. Among these isolates, Trichosporon asahii (108 isolates [81.2%]) was the leading species, followed by Trichosporon dermatis (7 isolates [5.3%]), Trichosporon asteroides (5 isolates [3.8%]), Trichosporon inkin (5 isolates [3.8%]), Trichosporon dohaense (3 isolates [2.3%]), and 1 isolate (0.7%) each of Trichosporon faecale, Trichosporon jirovecii, Trichosporon mucoides, Trichosporon coremiiforme, and Trichosporon montevideense Both the Vitek mass spectrometry (MS) (bioMérieux, Marcy l'Etoile, France) and Bruker Biotyper MS (Bruker Daltonics GmbH, Germany) platforms gave high levels (>97.5%) of correct identification when the species were present in the database. The geometric mean (GM) of amphotericin B MICs for T. asahii was 2-fold higher than that for non-asahii Trichosporon High fluconazole MICs (≥8 µg/ml) were observed for 25% of T. asahii isolates (27/108 isolates) and 16% of non-asahii Trichosporon (4/25 isolates) isolates. Itraconazole MICs were ≤0.5 µg/ml for 89.5% of the isolates. Voriconazole was the most potent antifungal agent in vitro, with a GM of 0.09 µg/ml. Genotyping of the isolates using IGS1 sequence alignment revealed that genotype 1 was most common (41.7%), followed by genotype 4 (31.5%), genotype 3 (23.1%), genotype 5 (0.9%), genotype 6 (0.9%), and genotype 7 (1.8%). Our data on species distribution, genotypes, and antifungal susceptibilities may contribute to a better understanding of the epidemiology of invasive Trichosporon infections throughout China.


Asunto(s)
Antifúngicos/farmacología , Genotipo , Infecciones Fúngicas Invasoras/epidemiología , Trichosporon/aislamiento & purificación , Tricosporonosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , China/epidemiología , ADN de Hongos/química , ADN de Hongos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Femenino , Técnicas de Genotipaje , Humanos , Lactante , Recién Nacido , Infecciones Fúngicas Invasoras/microbiología , Masculino , Técnicas Microbiológicas , Persona de Mediana Edad , Estudios Prospectivos , Análisis de Secuencia de ADN , Trichosporon/clasificación , Trichosporon/efectos de los fármacos , Trichosporon/genética , Tricosporonosis/microbiología , Adulto Joven
15.
J Org Chem ; 84(13): 8615-8629, 2019 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-31244152

RESUMEN

The efficient copper-catalyzed cyanoalkylation of amines via C-C bond cleavage has been demonstrated. Distinctive features of this procedure involves mild conditions, broad range of nitrogen nucleophiles, high selectivity, and good functional group tolerance, thus providing a useful approach for the C(sp3)-N bond formations. Most importantly, this protocol is applicable to the late-stage functionalization of natural products, amino acid esters, and drugs. Mechanistic studies suggest that a radical intermediate was involved in this transformation.

16.
J Org Chem ; 84(10): 6475-6482, 2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31050432

RESUMEN

An efficient iminyl radical-triggered 1,5-hydrogen-atom transfer/Heck-type coupling cascade has been achieved through visible-light photoredox catalysis. A variety of unactivated C(sp3)-H bonds have been alkenylated efficiently and selectively with easily available alkenes, providing an elegant route to γ-alkenylated ketone.

17.
Issues Ment Health Nurs ; 40(1): 73-78, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30633625

RESUMEN

This study aimed to explore the relationship of loneliness, perceived stress, and depressive symptoms among the Chinese rural empty nest elderly. The role of sense of coherence (SOC) as a moderating variable was investigated in a representative sample of older adults in Henan, China, from November 2016 to February 2017. Results indicated that perceived stress mediated the relationship between loneliness and depressive symptoms, and SOC acted as a moderator on this mediating model. The mediation effect of perceived stress was significant only when SOC was lower. The results emphasized the importance of perceived stress in older adults. SOC was a protective factor with regard to depressive symptoms, and improving SOC should be a focus of health promotion with the elderly.


Asunto(s)
Pueblo Asiatico/psicología , Depresión/epidemiología , Soledad , Población Rural , Sentido de Coherencia , Estrés Psicológico/epidemiología , Anciano , Anciano de 80 o más Años , China , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
J Transl Med ; 16(1): 331, 2018 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-30486885

RESUMEN

BACKGROUND: The ProCESS, ARISE, and ProMISe trials have failed to show that early goal-directed therapy (EGDT) reduces mortality in patients with severe sepsis and septic shock. Although lactate-guided therapy (LGT) has been shown to result in significantly lower mortality, its use remains controversial. Therefore, we performed a meta-analysis to evaluate EGDT vs. LGT or usual care (UC) in adult patients with severe sepsis and septic shock. METHODS: Relevant randomized controlled trials published from January 1, 2001 to March 30, 2017 were identified in PubMed, EMBASE, Web of Science, and the Cochrane Library. The primary outcome was mortality; secondary outcomes included red cell transfusions, dobutamine use, vasopressor infusion, and mechanical ventilation support within the first 6 h and Acute Physiology and Chronic Health Evaluation II (APACHE II) score. RESULTS: Sixteen studies enrolling 5968 patients with 2956 in EGDT, 2547 in UC, and 465 in LGT were included in this meta-analysis. Compared with UC, EGDT was associated with a lower mortality (10 trials; RR 0.85, 95% CI 0.74-0.97, P = 0.01), and this difference was more pronounced in the subgroup of UC patients with mortality > 30%. In addition, EGDT patients received more red cell transfusions, dobutamine, and vasopressor infusions within the first 6 h. Compared with LGT, EGDT was associated with higher mortality (6 trials; RR 1.42, 95% CI 1.19-1.70, P = 0.0001) with no heterogeneity (P = 0.727, I2 = 0%). CONCLUSION: EGDT seems to reduce mortality in adult patients with severe sepsis and septic shock, and the benefit may primarily be attributed to red cell transfusions, dobutamine administration, and vasopressor infusions within the first 6 h. However, LGT may result in a greater mortality benefit than EGDT.


Asunto(s)
Objetivos , Ácido Láctico/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Choque Séptico/tratamiento farmacológico , Adulto , Humanos , Sesgo de Publicación , Factores de Riesgo , Choque Séptico/mortalidad , Resultado del Tratamiento
19.
J Org Chem ; 83(7): 4239-4249, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29557652

RESUMEN

Metal-catalyzed cyanoalkylation/cyclization of olefinic 1,3-dicarbonyls with cycloketone oxime esters has been developed under redox-neutral conditions. This protocol provided a straightforward approach to diverse cyanoalkylated 2,3-dihydrofurans via a tandem ring-opening/addition/cyclization process.

20.
J Org Chem ; 83(2): 1046-1055, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29239182

RESUMEN

The copper-catalyzed cyclization of activated alkenes with cyclobutanone O-acyl oximes under redox-neutral conditions has been reported. This facile protocol provided an efficient approach to a variety of cyanoalkylated oxindoles and dihydroquinolin-2(1H)-ones with a broad substrate scope and excellent functional group tolerance. In this reaction, sequential C-C bond cleavage, radical addition, and cyclization processes were involved, wherein multiple bonds were constructed in a one-pot reaction. Mechanistic studies suggest that the reaction probably proceeded via a radical pathway.

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