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1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 532-540, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660863

RESUMO

OBJECTIVE: To investigate the molecular mechanism of proteolytic cleavage of unusually large von Willebrand Factor(ULVWF) on endothelial cells by ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats-13) in the absence of fluid shear stress, so as to provide a theoretical basis for the pathogenesis of thrombotic thrombocytopenic purpura (TTP) and other thrombotic disorders. METHODS: The ADAMTS13-mediated proteolysis of ULVWF on the surface of endothelial cells in the absence of fluid shear stress was observed through immunofluorescence microscopy. The variation in VWF antigen levels in the conditioned media were determined by ELISA assay. The levels of VWF and the proteolytic fragments released into the conditioned media were determined by ELISA assay and Western blot in the absence and presence of fluid shear stress or FVIII. The effect of ADAMTS13-mediated ULVWF cleavage on the normal distribution of plasma VWF multimers was evaluated by multimer analysis. Histamine stimulated human umbilical vein endothelial cells (HUVECs) were incubated with ADAMTS13 and various N- and C-terminally truncated mutants. Then the ULVWF that maintained binding to the cells were observed through immunofluorescence microscopy and the soluble ULVWF released from endothelial cells was determined by ELISA, so as to demonstrate the domains of ADAMTS13 required for proteolysis of ULVWF on endothelial cells. RESULTS: The ULVWF strings on the endothelial cell surface were rapidly proteolyzed by recombinant and plasma ADAMTS13 in the absence of fluid shear stress. This proteolytic processing of ULVWF depended on incubation time and ADAMTS13 concentration, but not shear stress and FVIII. The distribution of VWF releaseded by ADAMTS13-mediated proteolysis was quite similar to that secreted by endothelial cells under histamine stimulation, suggesting the ULVWF cleavage occured at the cell surface. The proteolysis of the ULVWF on endothelial cells required the Cys-rich(CysR) and spacer domains, but not the TSP1 2-8 and CUB domains of ADAMTS13. CONCLUSION: The ULVWF polymers on endothelial cells are sensitive to ADAMTS13-mediated cleavage even in the absence of fluid shear stress. The findings provide novel insight into the molecular mechanism of ADAMTS13-mediated ULVWF cleavage at the cellular level and may contribute to understanding of the pathogenesis of TTP and other thrombotic disorders.


Assuntos
Proteína ADAMTS13 , Células Endoteliais , Estresse Mecânico , Fator de von Willebrand , Humanos , Proteínas ADAM/metabolismo , Proteína ADAMTS13/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Proteólise , Púrpura Trombocitopênica Trombótica/metabolismo , Fator de von Willebrand/química , Fator de von Willebrand/metabolismo
2.
World J Clin Cases ; 10(21): 7585-7591, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36158025

RESUMO

BACKGROUND: Comamonas kerstersii (C. kerstersii) infections have considered as non-pathogenic to humans, however due to new techniques such as matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS), more cases have been identified. CASE SUMMARY: This is the first report of a maternal patient with a C. kerstersii bacteremia following caesarean section. Due to the severity of the patient's condition; high fever and rapidly progressing organ damage, the patient was transferred to the intensive care unit. C. kerstersii was detected by metagenomic next-generation sequencing testing. Based on the drug sensitivity test, appropriate antibiotic treatment was given and the patient recovered fully. CONCLUSION: This case report confirms that the detection via MALDI-TOF-MS and metagenomic next-generation sequencing testing provides a reliable basis for the diagnosis of this rare bacterial infection.

3.
Bioresour Technol ; 302: 122885, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32014733

RESUMO

Sulfide has attracted increasing attention due to its odor nuisance, toxicity and corrosion. Although variations in the nitrogen removal performance of anammox under sulfide stress have been reported previously, understanding the microorganisms at the molecular level is of greater significance. This study first deciphered the microbial community and functional gene response of anammox sludge to sulfide stress. Results showed that 20 mg L-1 sulfide could reduce specific anammox activity by 61.7%. The protein-like substances within extracellular polymeric substances were quenched at the end of the experiment. Moreover, the relative abundance of Candidatus Kuenenia significantly decreased from 28.7% to 6.4% while Thiobacillus increased from 0 to 7.2% due to sulfide stress. Furthermore, the abundances of functional genes (hzsA, hdh, nirK and nirS) significantly decreased when the sulfide concentration reached 20 mg L-1. These findings provide a further theoretical basis for the anammox process for nitrogen removal from wastewater containing sulfide.


Assuntos
Microbiota , Esgotos , Reatores Biológicos , Nitrogênio , Oxirredução , Sulfetos , Águas Residuárias
4.
Discov Med ; 27(150): 227-233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31421691

RESUMO

OBJECTIVE: The aim of this study was to investigate the characteristics of nasopharyngeal carcinoma (NPC) using contrast-enhanced ultrasonography (CEUS), including the enhancement patterns and the quantitative parameters. METHODS: Having been scanned using conventional ultrasonography (US) and CEUS, every case was confirmed to be NPC under endoscopic biopsy, and no case received any anti-tumor treatment before CEUS examinations. Tumor/node/metastasis stages were determined in accordance with 2002 AJCC 6th edition. Contrast enhancement patterns and quantitative parameters were observed. RESULTS: CEUS imaging of NPC showed that the tumor signal intensity enhanced early, rapidly, and remarkably, and decreased slowly later. The patterns of enhancement included spot/linear enhancement, peripheral enhancement, and mass enhancement, and two types of time intensity curves of NPC included type I and type II. There was a significant difference between peak intensity (PI) and T stage (P<0.05), whereas time-to-peak (TP) and slope did not show significant differences with T stage (P>0.05). CONCLUSION: CEUS is feasible to be applied to the nasopharynx region. The use of CEUS makes it possible to observe vascular permeability of NPC. Our results suggest that the quantitative parameter PI of nasopharyngeal carcinoma is significantly different from T stages. Thus, PI may serve as a potential noninvasive radiological prognostic indicator for NPC.


Assuntos
Meios de Contraste/química , Aumento da Imagem , Carcinoma Nasofaríngeo/diagnóstico por imagem , Ultrassonografia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/patologia , Estadiamento de Neoplasias
5.
Bioresour Technol ; 290: 121766, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302464

RESUMO

Cadmium (Cd) can cause the deterioration of biological systems through inhibiting the enzymes activity and disturbing the microbial metabolism. Although the influence of Cd on conventional wastewater treatment process has been studied, the response of anammox to Cd exposure still remains unclear. This study firstly investigated the adaption and restoration of anammox biomass to Cd(II) stress. Results showed that long-term exposure of anammox bacteria to 2 mg L-1 Cd(II) was beneficial for the reactor performance, while 5 mg L-1 Cd(II) would cause the decline of SAA, extracellular polymeric substance content and relative abundance of Candidatus kuenenia by 40%, 25% and 31%, respectively. Furthermore, these indexes could approximately recover to the initial status after withdrawing Cd(II) from the influent. Overall, the anammox biomass exhibited a certain adaption and restoration ability to the suppression of Cd(II). This study may provide key valuable information for the biological treatment of wastewater containing Cd(II).


Assuntos
Cádmio , Microbiota , Anaerobiose , Biomassa , Reatores Biológicos , Matriz Extracelular de Substâncias Poliméricas , Nitrogênio , Oxirredução
6.
Cytotechnology ; 68(3): 389-97, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25297007

RESUMO

Oridonin, which is isolated from Chinese herb Rabdosia rubescens (Hemsl.) Hara, has been implicated in regulation of tumor cell migration and invasion. In this study, treatment with oridonin enhanced the phosphorylation of myosin regulatory light chain (T18/S19) that regulates the ATPase activity of myosin IIA. Meanwhile, stress fibers were significantly more prominent after oridonin incubation, which impaired cell migration in transwell migration assays. All of these effects may be caused by the decreased interaction between myosin IIA and myosin phosphatase complex, but not kinases. Our data provide clear evidence of this novel pharmacological function for oridonin in treating cancer cell migration.

7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(5): 545-8, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26159016

RESUMO

OBJECTIVE: To explore the effect of Qingfei Huoxue Recipe (QHR) combined azithromycin in treatment of intractable pediatric mycoplasma pneumonia. METHODS: Totally 124 intractable pediatric mycoplasma pneumonia patients at our hospital were recruited in this study, and randomly assigned to the treatment group and the control group, 62 in each group. Patients in the control group took azithromycin, while those in the treatment group additionally took QHR. All patients received omnibearing systematic nursing. Therapeutic efficacy, clinical indices (such as disappearance time of cough and rales, recovery time of body temperature) , and the incidence of adverse reactions were observed. RESULTS: After treatment the total effective rate was 91.94% (57/62 cases) in the treatment group and 77. 42% (48/62 cases) in the control group with statistical difference (P < 0.05). Compared with the control group, disappearance time of cough and rales, recovery time of body temperature were obviously shortened in the treatment group with statistical difference (P < 0.01). There was statistical difference in the incidence of adverse reactions between the two groups [3.23% (2/62 cases) vs 38.71% (24/62 cases) , P < 0.01]. CONCLUSION: In clinical treatment for intractable pediatric mycoplasma pneumonia, Chinese medicine combined Western medicine plus scientific and systematic nursing showed more obvious advantages with significant efficacy, which was worth spreading.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Pneumonia por Mycoplasma/tratamento farmacológico , Azitromicina , Pesquisa Biomédica , Criança , Tosse , Humanos , Medicina Tradicional do Leste Asiático , Fitoterapia
8.
Org Biomol Chem ; 9(23): 8141-6, 2011 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22015954

RESUMO

We disclose two novel BODIPY dyes, which contain the bulky substituent, [(4-dimesitylboryl)phenyl]ethynyl at 2- and 2,6-positions. The steric bulkiness of the boryl group is effective to suppress the intermolecular interaction in the solid state and thus these two compounds display intense fluorescence not only in solution but also in the solid state. In addition, the BODIPY dyes display sensitive fluorescence responses to fluoride and cyanide anions through the complexation with the boron center of the boryl group and the subsequent decomposition of the BODIPY core, illustrating their potential uses for the fluorescence sensing of fluoride and cyanide ions.

9.
Org Lett ; 13(18): 4830-3, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21848331

RESUMO

A new class of organoboron compounds containing a boryl and an amino group at the o,o'-positions of biphenyls display bright through-space intramolecular charge transfer fluorescence owing to the close contact between the boryl and the amino groups. Binding of the fluoride ions results in the remarkable blue shift and color change of the fluorescence, enabling colorimetric and ratiometric fluoride ion sensing.

10.
Chem Commun (Camb) ; 47(19): 5518-20, 2011 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-21461421

RESUMO

Intense solid-state emissions with good to excellent quantum yields were achieved through the introduction of bulky electron-donating diphenylamino groups at the side positions of an electron-accepting para-terphenyl framework.

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