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1.
Cell Rep ; 37(9): 110069, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34852234

RESUMO

Cancer cells utilize rapidly elevated cellular antioxidant programs to accommodate chemotherapy-induced oxidative stress; however, the underlying mechanism remains largely unexplored. Here we screen redox-sensitive effectors as potential therapeutic targets for colorectal cancer (CRC) treatment and find that cyclophilin A (CypA) is a compelling candidate. Our results show that CypA forms an intramolecular disulfide bond between Cys115 and Cys161 upon oxidative stress and the oxidized cysteines in CypA are recycled to a reduced state by peroxiredoxin-2 (PRDX2). Furthermore, CypA reduces cellular reactive oxygen species levels and increases CRC cell survival under insults of H2O2 and chemotherapeutics through a CypA-PRDX2-mediated antioxidant apparatus. Notably, CypA is upregulated in chemoresistant CRC samples, which predicts poor prognosis. Moreover, targeting CypA by cyclosporine A exhibits promising efficacy against chemoresistant CRC when combined with chemotherapeutics. Collectively, our findings highlight CypA as a component of cellular noncanonical antioxidant defense and as a potential druggable therapeutic target to ameliorate CRC chemoresistance.

2.
Nano Lett ; 21(22): 9761-9771, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34767372

RESUMO

Based on the high frequency of concurrent adenomatous polyposis coli (APC) and KRAS mutations and their strong cooperative interaction in human colorectal cancer (CRC) promotion, we herein develop a CRISPR-Cas9-based genome-editing nanomedicine to target both APC and KRAS mutations for the treatment of CRC. To this end, a hyaluronic acid (HA)-decorated phenylboronic dendrimer (HAPD) was designed for the targeted delivery of Cas9 ribonucleoprotein (RNP), by which both APC and KRAS genetic mutations harboring in CRC cells can be synergistically disrupted. Systemic administration of Cas9 RNP targeting APC and KRAS enabled by HAPD significantly inhibits tumor growth on xenografted and orthotopic CRC mouse models and also greatly prevents CRC-induced liver metastasis and lung metastasis. Thus, this duplex genome-editing system provides a promising gene therapy strategy for the treatment of human CRC and can be extended to other types of cancers with activated Wnt/ß-catenin and RAS/extracellular signal-regulated kinase (ERK) pathways.

3.
SynOpen ; 5(3): 173-228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34825124

RESUMO

This Graphical Review provides a concise overview of the manifold and mechanistically diverse methods that enable the functionalization of sp3 C-H bonds in amines and their derivatives.

4.
Clin Lab ; 67(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758242

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that brings a significant public health challenge. A rapid and simple method is necessary for testing suspected samples and screening the population. METHODS: To better monitor sample effectiveness, this study described a method to detect nucleocapsid protein gene (N gene) of SARS-CoV-2 and human ACTB gene employing real-time duplex reverse transcription multienzyme isothermal rapid amplification (RT-MIRA) assays. RESULTS: The established real-time duplex RT-MIRA assays showed that no cross-reactions were observed to other pathogens and the detection limit was 100 copies/reaction. Using simulated clinical samples to test established assays further and the amplification process took no more than 20 minutes at 42°C. CONCLUSIONS: RT-MIRA assays are faster and easier than reverse transcription real-time polymerase chain reaction (RT-PCR). It is expected to be further optimized and evaluated in the detection of SARS-CoV-2 confirmed cases.


Assuntos
COVID-19 , Transcrição Reversa , Humanos , Técnicas de Amplificação de Ácido Nucleico , SARS-CoV-2 , Sensibilidade e Especificidade
5.
Nat Commun ; 12(1): 6841, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824273

RESUMO

Hierarchically ordered chiral crystals have attracted intense research efforts for their huge potential in optical devices, asymmetric catalysis and pharmaceutical crystal engineering. Major barriers to the application have been the use of costly enantiomerically pure building blocks and the difficulty in precise control of chirality transfer from molecular to macroscopic level. Herein, we describe a strategy that offers not only the preferred formation of one enantiomorph from racemic solution but also the subsequent enantiomer-specific oriented attachment of this enantiomorph by balancing stereoselective and non-stereoselective interactions. It is demonstrated by on-demand switching the sign of fan-shaped crystal aggregates and the configuration of their components only by changing the molar mass of tailored polymeric additives. Owing to the simplicity and wide scope of application, this methodology opens an immediate opportunity for facile and efficient fabrication of one-handed macroscopic aggregates of homochiral organic crystals from racemic starting materials.

6.
Mol Nutr Food Res ; : e2100602, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34786857

RESUMO

SCOPE: Recent studies have linked high consumption of red and processed meats to an increased risk of non-alcoholic fatty liver disease, and cooking-induced oxidation of proteins and amino acids might be contributing factors. Herein, this study investigates the influence of oxidized pork and the protein oxidation biomarker dityrosine (Dityr) on hepatic steatosis in mice. METHODS AND RESULTS: Low- and high-oxidative injury pork (LOP and HOP) are freeze-dried to prepare mouse diets. Mice are fed a diet of either the control, LOP, HOP, LOP+Dityr, or Dityr for 12 weeks. HOP and Dityr intake induced oxidative stress and inflammation that impaired thyroid function and peripheral metabolism (reduced type 1 deiodinase activity) of thyroid hormones (THs). These lead to a decrease in the circulating as well as liver THs and induced hepatic steatosis. This process might be regulated through reduced TH levels and altered TH target genes and proteins related to hepatic lipid metabolism that ultimately inhibited hepatic energy metabolism, as indicated by increased hepatic lipid synthesis, decreased hepatic lipid catabolism, and fatty acid oxidation. CONCLUSION: HOP intake could induce hepatic steatosis by impairing TH function. Dityr plays an important role in the HOP-induced harmful effects.

7.
Opt Lett ; 46(22): 5627-5630, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780422

RESUMO

A time magnifier based on space-time duality has demonstrated comprehensive applications owing to its promising temporal resolution. However, conventional parametric time magnifiers are inherently polarization-sensitive; their output intensity depends not only on the intensity but also the polarization of signal under test (SUT). Therefore, they are mainly applied to SUT with fixed polarization. On the other hand, many complex optical signals exhibit simultaneous intensity and polarization dynamics. In this Letter, a polarization-independent (PI) time magnifier at 485-fs temporal resolution is first demonstrated, which provides accurate intensity information even for polarization-related signals. The PI time magnifier de-convolves intensity and polarization information. It, therefore, paves the way for in-depth analysis of various complex ultrafast phenomena involving simultaneous intensity and polarization dynamics such as rogue waves and vector solitons.

8.
Front Immunol ; 12: 746585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721416

RESUMO

Irritable bowel syndrome with diarrhea and functional diarrhea are both functional bowel disorders that cause chronic diarrhea. Chronic diarrhea is closely related to daily life and the psychological condition of diarrhea in patients, and probiotics can play a significant role in alleviating chronic diarrhea in some research. Lactobaccilus plantarum CCFM1143 can relieve diarrhea in mice caused by enterotoxigenic Escherichia coli (ETEC); however, its clinical effects remain unclear. This study aimed to assess the effects of CCFM1143 as a therapy for chronic diarrhea patients. Fifty-five patients with chronic diarrhea were randomly assigned into the probiotic group (n = 28) and the placebo group (n = 27), receiving the routine regimen with or without probiotics for 4 weeks, respectively. CCFM1143 can mitigate the apparent clinical symptoms and improve the health status and quality of life of patients. In addition, it could inhibit the increase in interleukin 6 (IL-6) and the decrease in motilin; modulate the short-chain fatty acids, especially acetic and propionic acids; and regulate the gut microbiota, particularly reducing the abundance of Bacteroides and Eggerthella and enriching the abundance of Akkermansia, Anaerostipes, and Terrisporobacter. In addition, treatment with probiotics showed clinical effectiveness in managing chronic diarrhea when compared with the placebo group. The findings could help to develop and further the application of probiotics for chronic diarrhea.

9.
Front Med (Lausanne) ; 8: 691173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746167

RESUMO

Purpose: To evaluate the difference of the lens nuclear density measured before and after mydriasis by using the IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany) and the Pentacam Scheimpflug imaging (Pentacam HR, Oculus Incorporation, Wetzlar, Germany) and investigate the relationship between the measurement data and the phacoemulsification parameters. Methods: Patients with age-related nuclear cataracts diagnosed on the slit-lamp examination were enrolled in the age range of 53-76 years. No patient had a history of ocular surgery, laser treatment, or general disorders affecting vision. The mean optical density (OD) was measured by the IOLMaster 700 by using the Image-Pro® Plus software before and after mydriasis. The Pentacam nucleus densitometry (PND) was obtained automatically from the Pentacam Scheimpflug imaging and compared with OD. The correlation between OD and effective phacoemulsification time (EPT), PND, and EPT were analyzed, respectively. Results: In this study, 53 eyes of 52 patients were evaluated. Before and after mydriasis, the mean OD values were 64.34 ± 23.31 and 63.81 ± 23.21 pixel units, respectively; the mean PND values were 28.51 ± 11.42 and 25.41 ± 11.31, respectively; and the mean EPT value was 6.24 ± 3.49. The Bland-Altman analysis showed that the lens nuclear densities of the two devices were highly consistent. There was no significant difference in the OD values (t = 0.455, p > 0.05) before and after mydriasis, but the difference has existed in the PND values (t = 2.509, p < 0.05). The OD and PND values were positively correlated with EPT before and after mydriasis (r OD-Before = 0.604, r OD-After = 0.593, r PND-Before = 0.701, and r PND-After = 0.891, p < 0.01). Conclusion: The combination of the IOLMaster 700 and the Image-Pro® Plus software can quantitatively evaluate the degree of the cataract lens opacification. It has good consistency with the Pentacam and is positively correlated with the phacoemulsification parameters. It is expected to become a new method to predict the phacoemulsification parameters before and during cataract surgery.

10.
Front Bioeng Biotechnol ; 9: 750444, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778227

RESUMO

Circulating tumor cells (CTCs) play a crucial role in solid tumor metastasis, but obtaining high purity and viability CTCs is a challenging task due to their rarity. Although various works using spiral microchannels to isolate CTCs have been reported, the sorting purity of CTCs has not been significantly improved. Herein, we developed a novel double spiral microchannel for efficient separation and enrichment of intact and high-purity CTCs based on the combined effects of two-stage inertial focusing and particle deflection. Particle deflection relies on the second sheath to produce a deflection of the focused sample flow segment at the end of the first-stage microchannel, allowing larger particles to remain focused and entered the second-stage microchannel while smaller particles moved into the first waste channel. The deflection of the focused sample flow segment was visualized. Testing by a binary mixture of 10.4 and 16.5 µm fluorescent microspheres, it showed 16.5 µm with separation efficiency of 98% and purity of 90% under the second sheath flow rate of 700 µl min-1. In biological experiments, the average purity of spiked CTCs was 74% at a high throughput of 1.5 × 108 cells min-1, and the recovery was more than 91%. Compared to the control group, the viability of separated cells was 99%. Finally, we validated the performance of the double spiral microchannel using clinical cancer blood samples. CTCs with a concentration of 2-28 counts ml-1 were separated from all 12 patients' peripheral blood. Thus, our device could be a robust and label-free liquid biopsy platform in inertial microfluidics for successful application in clinical trials.

11.
Cell Death Discov ; 7(1): 351, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772908

RESUMO

Human Dachshund homolog 1 (DACH1) is usually defined as a tumor suppressor, which plays an influential role in tumor growth and metastasis in a variety of cancer cells. However, the underlying mechanisms in these process are not yet fully clarified. In this study, DACH1 inhibited the invasion and metastasis of breast cancer cells by decreasing MMP9 expression. Mechanistically, DACH1 represses the transcriptional level of MMP9 by interacting with p65 and c-Jun at the NF-κB and AP-1 binding sites in MMP9 promoter respectively, and the association of DACH1 and p65 promote the recruitment of HDAC1 to the NF-κB binding site in MMP9 promoter, resulting in the reduction of the acetylation level and the transcriptional activity of p65. Accordingly, the level of MMP9 was decreased. In conclusion, we found a new mechanism that DACH1 could inhibit the metastasis of breast cancer cells by inhibiting the expression of MMP9.

12.
Cells ; 10(10)2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34685686

RESUMO

Following efficient tumor therapy, some cancer cells may survive through a dormancy process, contributing to tumor recurrence and worse outcomes. Dormancy is considered a process where most cancer cells in a tumor cell population are quiescent with no, or only slow, proliferation. Recent advances indicate that redox mechanisms control the dormant cancer cell life cycle, including dormancy entrance, long-term dormancy, and metastatic relapse. This regulatory network is orchestrated mainly through redox modification on key regulators or global change of reactive oxygen species (ROS) levels in dormant cancer cells. Encouragingly, several strategies targeting redox signaling, including sleeping, awaking, or killing dormant cancer cells are currently under early clinical evaluation. However, the molecular mechanisms underlying redox control of the dormant cancer cell cycle are poorly understood and need further exploration. In this review, we discuss the underlying molecular basis of redox signaling in the cell life cycle of dormant cancer and the potential redox-based targeting strategies for eliminating dormant cancer cells.

13.
Exp Cell Res ; 409(1): 112896, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34717920

RESUMO

M2 macrophages are crucial components of the tumour microenvironment and have been shown to be closely related to tumour progression. Co-culture with 4.1R-/- M2 macrophages enhances the malignancy of colon cancer (CC), but the mechanism remains unclear. Here, we report that protein 4.1R knockout reduced the phagocytosis of M2 macrophages (M-CSF/IL-4-treated bone marrow cells) and promoted MC38 colon cancer cell proliferation, migration, invasion, tumour formation and epithelial-mesenchymal transition (EMT), which are regulated by M2 macrophages. Further mechanistic dissection revealed that the 4.1R knockout upregulated vascular endothelial growth factor A (VEGFA) secreted by M2 macrophages and promoted colon cancer progression by activating the PI3K/AKT signalling pathway. In summary, our present study identified that 4.1R downregulates VEGFA secretion in M2 macrophages and delays the malignant potential of colon cancer by inhibiting the PI3K/AKT signalling pathway.

14.
Cell Transplant ; 30: 9636897211055042, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34699255

RESUMO

Swine hepatitis E (SHE) is a new type of zoonotic infectious disease caused by swine hepatitis E virus (SHEV). Open reading frame 3 (ORF3) is a key regulatory and virulent protein of SHEV. Circular RNAs (circRNAs) are a special kind of non-coding RNA molecule, which has a closed ring structure. In this study, to identify the circRNA profile in host cells affected by SHEV ORF3, adenovirus ADV4-ORF3 mediated the overexpression of ORF3 in HepG2 cells, whole genome sequencing was used to investigate the differentially expressed circRNAs, GO and KEGG were performed to enrichment analyze of differentially expressed circRNA-hosting gene, and Targetscan and miRanda softwares were used to analyze the interaction between circRNA and miRNA. The results showed adenovirus successfully mediated the overexpression of ORF3 in HepG2 cells, 1,105 up-regulation circRNAs and 1,556 down-regulation circRNAs were identified in ADV4-ORF3 infection group compared with the control. GO function enrichment analysis of differentially expressed circRNAs-hosting genes classified three main categories (cellular component, biological process and molecular function). KEGG pathway enrichment analysis scatter plot showed the pathway term of top20. The circRNAs with top10 number of BS sites for qRT-PCR validation were selected to confirmed, the results indicated that the up-regulated hsa_circ_0001423 and hsa_circ_0006404, and down-regulated of hsa_circ_0004833 and hsa_circ_0007444 were consistent with the sequencing data. Our findings first preliminarily found that ORF3 protein may affect triglyceride activation (GO:0006642) and riboflavin metabolism (ko00740) in HepG2 cells, which provides a scientific basis for further elucidating the effect of ORF3 on host lipid metabolism and the mechanism of SHEV infection.

15.
Front Bioeng Biotechnol ; 9: 692901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595157

RESUMO

Erythromycins produced by Saccharopolyspora erythraea have broad-spectrum antibacterial activities. Recently, several TetR-family transcriptional regulators (TFRs) were identified to control erythromycin production by multiplex control modes; however, their regulatory network remains poorly understood. In this study, we report a novel TFR, SACE_0303, positively correlated with erythromycin production in Sac. erythraea. It directly represses its adjacent gene SACE_0304 encoding a MarR-family regulator and indirectly stimulates the erythromycin biosynthetic gene eryAI and resistance gene ermE. SACE_0304 negatively regulates erythromycin biosynthesis by directly inhibiting SACE_0303 as well as eryAI and indirectly repressing ermE. Then, the SACE_0303 binding site within the SACE_0303-SACE_0304 intergenic region was defined. Through genome scanning combined with in vivo and in vitro experiments, three additional SACE_0303 target genes (SACE_2467 encoding cation-transporting ATPase, SACE_3156 encoding a large transcriptional regulator, SACE_5222 encoding α-ketoglutarate permease) were identified and proved to negatively affect erythromycin production. Finally, by coupling CRISPRi-based repression of those three targets with SACE_0304 deletion and SACE_0303 overexpression, we performed stepwise engineering of the SACE_0303-mediated mini-regulatory network in a high-yield strain, resulting in enhanced erythromycin production by 67%. In conclusion, the present study uncovered the regulatory network of a novel TFR for control of erythromycin production and provides a multiplex tactic to facilitate the engineering of industrial actinomycetes for yield improvement of antibiotics.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34599713

RESUMO

In this study, the biocarbon derived from aerobic granular sludge with different nutritive proportions was modified by Cu(NO3)2•3H2O (Cu-BC) to improve its adsorption capacity of doxycycline hydrochloride (DOX). The surface area, pores, functional groups, and element composition of biocarbon were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area, X-ray photoelectron spectrometer, X-ray diffraction (XRD), the X-ray photoelectron spectrometer, and Fourier transform infrared spectrometry (FT-IR), respectively. Effects of DOX concentration, initial pH, and background electrolyte on adsorption effects of composite were analyzed. Furthermore, the adsorption kinetics, isotherm, thermodynamics, and diffusion model were investigated. Results demonstrated that biocarbons which were prepared with aerobic granular sludge under different nutritive proportions presented different performances. The BET specific surface area of Cu-NaAC/AGS-BC was 260.1592 m2/g, and the micropore volume was 0.054101 cm3/g. The BET specific surface area of Cu-GLC /AGS-BC was only 10.6821 m2/g, and the micropore volume was 0.008687 cm3/g. Both kinds of modified biochar contain a large number of oxygen-containing functional groups. The highest adsorption efficiency of Cu-BC could reach 99.54%. The adsorption of DOX on two modified biocarbons conforms to the pseudo-second-order dynamic model and Temkin isothermal model.

17.
ACS Omega ; 6(38): 24515-24525, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34604633

RESUMO

The distribution of hydroxyl (OH) radicals in the laminar diffusion flame of n-heptane was studied by planar laser-induced fluorescence (PLIF). The influences of nitrogen (N2) and carbon dioxide (CO2) dilution on the formation and distribution of OH radicals were analyzed. The corresponding dilution ratios (volume fractions) of both N2 and CO2 vary from 0 to 5%. The results show that for the n-heptane flame, the OH radical is mainly concentrated in the two wings of the flame, presenting a radially approximate symmetrical distribution. Both N2 and CO2 dilutions decrease the intensity of the maximum OH radical fluorescence and the total OH radical fluorescence. Moreover, the flame temperature decreases more significantly with the CO2 dilution ratio due to the combination of the dilution effect and thermal effect.

19.
Cell Death Dis ; 12(10): 910, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34611143

RESUMO

Gastric cancer remains the third leading cause of cancer-related mortality worldwide. Emerging evidence has shown that circular RNAs (circRNAs) play a critical regulatory role in the occurrence and development of various cancers through sponging miRNAs or acting as RNA-binding protein (RBP) sponges. We found that circUBE2Q2 was significantly upregulated in GC tissues and cell lines. Knockdown of circUBE2Q2 inhibited proliferation, migration, invasion, and glycolysis, and increased autophagy in vitro. In addition, knockdown of circUBE2Q2 inhibited GC tumorigenicity and metastasis potential in vivo. A series of experiments were performed to confirm that circUBE2Q2 regulates GC progression via the circUBE2Q2-miR-370-3p-STAT3 axis and promotes tumor metastasis through exosomal communication. Further in vivo experiments confirmed that, combination treatment of circUBE2Q2 knocking down and STAT3 inhibitor has synergistic effects on the gastric cancer growth inhibition, which provides a possibility to enhance the sensitivity of targeted drugs to gastric cancer through targeting circUBE2Q2. Our findings revealed that circUBE2Q2 may serve as a new proliferation-promoting factor and prognostic marker in gastric cancer.

20.
Foods ; 10(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34681487

RESUMO

Methionine restriction (MR) has been reported to have many beneficial health effects, including stress resistance enhancement and lifespan extension. However, the effects of MR on the splenic metabolic dysfunction induced by obesity in mice remain unknown. This study aimed to investigate the scientific problem and clarify its possible mechanisms. C57BL/6J mice in the control group were fed a control diet (0.86% methionine, 4.2% fat) for 34 weeks, and others were fed a high-fat diet (0.86% methionine, 24% fat) for 10 weeks to establish diet-induced obese (DIO) mouse models. Then, the obtained DIO mice were randomly divided into two groups: the DIO group (DIO diet), the DIO + MR group (0.17% methionine, 24% fat) for 24 weeks. Our results indicated that MR decreased spleen weight, and spleen and plasma lipid profiles, promoted lipid catabolism and fatty acid oxidation, glycolysis and tricarboxylic acid cycle metabolism, and improved mitochondrial function and ATP generation in the spleen. Moreover, MR normalized the splenic redox state and inflammation-related metabolite levels, and increased plasma levels of immunoglobulins. Furthermore, MR increased percent lean mass and splenic crude protein levels, activated the autophagy pathway and elevated nucleotide synthesis to maintain protein synthesis in the spleen. These findings indicate that MR can ameliorate metabolic dysfunction by reducing lipid accumulation, oxidative stress, and inflammation in the spleen, and the mechanism may be the activation of autophagy pathway.

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