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1.
Anal Chem ; 93(46): 15412-15419, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34762397

RESUMO

Designing analytical approaches for enzymatic activity monitoring with high sensitivity and selectivity is of critical value for the diagnosis of diseases and biomedical studies. In this study, we have created a facile one-step synthetic route to prepare orange-red color and yellow fluorescent silicon-containing nanoparticles (Si CNPs) by mixing 3(2-aminoethylamino) propyl (dimethoxymethylsilane) and hydroquinone (HQ) in an aqueous solution. Inspired by the HQ-regulated facile synthetic step and the generation of HQ from α-glucosidase (α-Glu)-catalyzed hydrolysis of 4-hydroxyphenyl-α-d-glucopyranosyl (4-HPαDG), we have designed a straightforward colorimetric and fluorometric α-Glu activity assay using a commercially available 4-HPαDG as the α-Glu substrate. Fluorescent and colorimetric assays for α-Glu activity measurement have been thereby established and exhibited detection limits as low as 0.0032 and 0.0046 U/mL, respectively. Under single excitation at 370 nm, the prepared Si CNPs emitted yellow fluorescence at 520 nm and exhibited an absorbance peak at 390 nm. In addition, the proposed approach reveals various advantages including easy operation, time-saving, and good anti-interference ability. Hence, it could improve the progress of fluorometric and colorimetric enzymatic activity assays with high sensitivity and simplicity. Moreover, the proposed approach was applied for α-Glu inhibitor screening, and its feasibility in real samples was measured by detecting the α-Glu activity in human serum samples.


Assuntos
Colorimetria , Nanopartículas , Corantes Fluorescentes , Humanos , Silício , alfa-Glucosidases
2.
Front Immunol ; 12: 711980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594327

RESUMO

Regulatory B cells (Breg) are considered as immunosuppressive cells. Different subsets of Breg cells have been identified both in human beings and in mice. However, there is a lack of unique markers to identify Breg cells, and the heterogeneity of Breg cells in different organs needs to be further illuminated. In this study, we performed high-throughput single-cell RNA sequencing (scRNA-seq) and single-cell B-cell receptor sequencing (scBCR-seq) of B cells from the murine spleen, liver, mesenteric lymph nodes, bone marrow, and peritoneal cavity to better define the phenotype of these cells. Breg cells were identified based on the expression of immunosuppressive genes and IL-10-producing B (B10) cell-related genes, to define B10 and non-B10 subsets in Breg cells based on the score of the B10 gene signatures. Moreover, we characterized 19 common genes significantly expressed in Breg cells, including Fcrl5, Zbtb20, Ccdc28b, Cd9, and Ptpn22, and further analyzed the transcription factor activity in defined Breg cells. Last, a BCR analysis was used to determine the clonally expanded clusters and the relationship of Breg cells across different organs. We demonstrated that Atf3 may potentially modulate the function of Breg cells as a transcription factor and that seven organ-specific subsets of Breg cells are found. Depending on gene expression and functional modules, non-B10 Breg cells exhibited activated the TGF-ß pathway, thus suggesting that non-B10 Breg cells have specific immunosuppressive properties different from conventional B10 cells. In conclusion, our work provides new insights into Breg cells and illustrates their transcriptional profiles and BCR repertoire in different organs under physiological conditions.

3.
J Org Chem ; 86(16): 11006-11010, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-33326231

RESUMO

Narjatamolide (1), an unusual homoguaiane sesquiterpene lactone, was isolated from the roots and rhizomes of Nardostachys jatamansi DC. It represents the new carbon skeleton of a homoguaiane sesquiterpenoid possessing an additional acetate unit spiro-fused with C-4 and C-15 to form a cyclopropane ring. The structure of 1 was elucidated by extensive spectroscopic analyses, and the absolute configuration was confirmed by the electronic circular dichroism (ECD) calculations and X-ray single-crystal diffraction analysis. Compound 1 showed antiproliferative effects against BEL-7402 cell lines with an IC50 value of 5.67 ± 1.43 µM, and the mechanism study showed that 1 induces cell cycle of BEL-7402 cell lines arrest at G2/M phase.


Assuntos
Nardostachys , Sesquiterpenos , Lactonas/farmacologia , Estrutura Molecular , Rizoma , Sesquiterpenos/farmacologia
4.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(12): 1609-1614, 2017 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-29292253

RESUMO

OBJECTIVE: To construct a cell model of 4.1R gene knockout in murine macrophage cell line RAW264.7 using CRISPR/Cas9 technique. METHODS: Three high?grade small?guide RNAs (sgRNAs) that could specifically identify 4.1R gene were synthesized and inserted into lentiCRISPRv2 plasmid. RAW264.7 cells were infected with sgRNA?Cas9 lentivirus from 293T cells transfected with the recombinant sgRNA?lentiCRISPRv2 plasmid, and the positive cells were screened using puromycin and the monoclonal cells were obtained. The expression of 4.1R protein in the monoclonal cells was measured by Western blotting, and the mutation site was confirmed by sequence analysis. Result A 4.1R gene knockout RAW264.7 cell line was obtained, which showed a 19?bp deletion mutation in the 4.1R gene sequence and obviously enhanced proliferation. CONCLUSION: We successfully constructed a 4.1R gene knockout macrophage cell line using CRISPR/Cas9 technique, which may facilitate further investigation of the function of 4.1R in macrophages.


Assuntos
Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Proteínas dos Microfilamentos/genética , RNA Guia/genética , Animais , Camundongos , Células RAW 264.7
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(11): 965-70, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22336268

RESUMO

OBJECTIVE: To explore a new method for finding more HIV/AIDS. METHODS: In September 2009, newly reported HIV-infected individuals from May to August, 2009 in Dehong prefecture were asked to participate in a survey which requested demographic characteristics, history of high-risk behaviors and contact information of individuals with whom they had high risky contacts. People with risky contacts with HIV-infected cases (index cases) were also approached to participate in this survey and HIV testing was provided. RESULTS: A total of 342 HIV-infected individuals were newly reported and served as index cases from May to August, 2009. Among them, 47.1% (161/342) were transmitted by regular sexual partners. Through three-round surveys, 218 contacts were traced and among them, 84.9% (185/218) were traced by regular heterosexual partners. HIV positive rate of the tested was 34.7% (60/173) in the first-round tracing and 12.5% (1/8) in the second one. Among the 560 individuals (index cases and their high-risk contacts), the proportions of having regular heterosexual partners, non-regular and non-commercial sexual partners, commercial sexual heterosexual partners and men having sex men were 87.9% (492/560), 18.9% (106/560), 22.3% (125/560) and 0.3% (1/318), respectively, while the proportion of having never used condoms when having sex with the above four types sexual partners were 73.8% (363/492), 72.6% (77/106), 63.2% (79/125) and 0.0% (0/1), respectively. CONCLUSION: As an epidemiological method for HIV/AIDS finding, contact tracing identified a large number of HIV infectors who were traced by newly reported HIV-infected individuals.


Assuntos
Busca de Comunicante/métodos , Infecções por HIV/epidemiologia , Síndrome de Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 31(1): 39-42, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20302696

RESUMO

OBJECTIVE: To trace and provide HIV-testing among those having contacts with HIV-infected individuals at various levels in Dehong prefecture, Yunnan province and to evaluate the effectiveness and feasibility of such investigation as a supplemental strategy for HIV testing and control. METHODS: Newly reported HIV infections from August throughout October in Dehong prefecture, in 2008 were asked to provide contact information of persons whom they had high risk contacts with. Persons having had risk contacts with HIV-infected cases were here of interviewed and their blood tested on the sero-status of HIV. RESULTS: A total of 335 HIV cases were newly reported during this three-month period. A total of 309 cases of them and 148 HIV infections identified thereafter from their risk contacts were under informed consent, to participate in this study. A total number of 3395 risk contacts were reported, of whom only 20.7% (704/3395) had 'contact information' and 51.3% (361/704) were successfully located and interviewed, including 117 previously confirmed HIV infections and 244 people with unknown HIV status. The majority of them (203 or 83.2% of 244) were then tested for HIV and 56 (27.6% of 203) were tested positive for HIV. The proportion of having detailed contact information and the proportion of being traced or followed among reported risk contacts of HIV infections were 68.8% and 68.2% for spouses of HIV patients, respectively, which were much higher than those among commercial sex partners (1.2% and 16.7%), casual sex partners (37.3% and 22.3%) and peers who sharing needles (34.1% and 56.4%). CONCLUSION: Newly reported HIV infections reported a large number of risk contacts and new HIV infections were identified among them. It was extremely difficult to trace commercial sex partners or casual sex partners on their HIV infection status. Nevertheless, tracing the risk contacts of newly reported HIV infections seemed to be helpful in identifying new HIV infections and in understanding the nature of transmission towards controlling the HIV epidemics.


Assuntos
Busca de Comunicante , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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