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1.
Postepy Dermatol Alergol ; 41(1): 66-71, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38533362

ABSTRACT

Introduction: Melasma is an acquired hypermelanosis and occurs in areas exposed to sunlight. Aim: To investigate the effectiveness of Danggui Shaoyao powder (DSP) as a complementary drug in the treatment of melasma. Material and methods: A total of 40 melasma patients over the age of 18 who met the inclusion criteria entered the study randomly in two DSP + Hydroquinone (DSP + H) and Hydroquinone (H) groups. Results: At the beginning of the study, the average MASI score of the two groups of patients had no statistical difference (DSP + H: 15.79 ±1.01 vs. H: 15.37 ±1.17, p = 0.23). But from the eighth week of treatment, the MASI score of the patients decreased significantly and in the DSP + H group it decreased statistically significantly compared to the H group (DSP + H: 5.83 ±0.97 vs. H: 8.29 ±2.23, p < 0.001 for the eighth week and DSP + H: 3.60 ±0.58 vs. H: 5.52 ±1.73, p < 0.001 for the twelfth week of the treatment). It means after 12 weeks of treatment, the average MASI score of patients in the DSP + H group decreased by 77.26 ±2.70%, but in the grroup H, it decreased by 64.31 ±9.68% (p < 0.001). Dynamic PGA showed that excellent treatment occurred in 65% of the + H group H, but only 20% of the H group (p = 0.01). Conclusions: Oral DSP for 12 weeks along with hydroquinone cream can significantly reduce the MASI score of melasma patients and increase the patients' recovery and satisfaction.

2.
Value Health ; 27(2): 153-163, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38042333

ABSTRACT

OBJECTIVES: To assess the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine as second-line therapy for patients with human epidermal growth factor receptor 2 positive metastatic breast cancer from a US healthcare sector perspective. METHODS: A 3-state partitioned survival model was developed to estimate the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine. For both treatments, modeled patients were administered treatment intravenously every 3 weeks indefinitely or until disease progression. Transition parameters were principally derived from the updated DESTINY-Breast03 phase III randomized clinical trial. Costs include drug costs extracted from Centers for Medicare and Medicaid Services average sales price and administrative, adverse event, and third-line therapy costs derived from published literature, measured in 2022 US dollars. Health utilities for health states and disutilities for adverse events were sourced from published literature. Effects were measured in quality-adjusted life years (QALYs). We conducted both probabilistic sensitivity analysis and comprehensive scenario analysis to test model assumptions and robustness, while utilizing a lifetime horizon. RESULTS: In our base-case analysis, total costs for trastuzumab deruxtecan were $1 266 945, compared with $820 082 for trastuzumab emtansine. Total QALYs for trastuzumab deruxtecan were 5.09, compared with 3.15 for trastuzumab emtansine. The base-case incremental cost-effectiveness ratio was $230 285/QALY. Probabilistic sensitivity analysis indicated that trastuzumab deruxtecan had an 11.1% probability of being cost-effective at a $100 000 per QALY willingness-to-pay threshold. CONCLUSIONS: Despite the higher efficacy of trastuzumab deruxtecan in patients with human epidermal growth factor receptor 2 positive metastatic breast cancer, our findings raise concern regarding its value at current prices.


Subject(s)
Breast Neoplasms , Camptothecin/analogs & derivatives , Immunoconjugates , Aged , Humans , United States , Female , Ado-Trastuzumab Emtansine/therapeutic use , Cost-Effectiveness Analysis , Cost-Benefit Analysis , Medicare , Trastuzumab , Receptor, ErbB-2/metabolism , Quality-Adjusted Life Years , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
3.
Phytochemistry ; 217: 113905, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37913836

ABSTRACT

Three unusual oleanane-derived triterpenoids, stytontriterpenes A-C (1-3), were isolated from the resin of Styrax tonkinensis together with an oleanane-lactone (stytontriterpene D, 4). Their structures and absolute configurations were characterised using a combination of spectroscopic analysis, electronic circular dichroism, and theoretical calculations. 1 and 2 belong to nor-oleanane with rare spiro D/E rings and 3 contains one infrequent C32 scaffold. 1 considerably suppressed the number of adhered leukemic monocytes (THP-1) to human umbilical vein endothelial cells and attenuated the upregulations of mRNA and protein levels of intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 at 5 µM, suggesting that 1 might be a promising anti-vascular inflammatory chemical for atherosclerosis therapy. Plausible biosynthetic pathways for 1-4 are also proposed.


Subject(s)
Atherosclerosis , Triterpenes , Humans , Styrax/chemistry , Triterpenes/chemistry , Resins, Plant/chemistry , Human Umbilical Vein Endothelial Cells , Atherosclerosis/drug therapy , Atherosclerosis/metabolism
4.
J Hazard Mater ; 465: 133201, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38113733

ABSTRACT

Silver (Ag)-containing nanomaterials have emerged as promising alternatives or adjuvants to antibiotics. Ongoing research is dedicated to enhance their antimicrobial efficacy, stability, biocompatibility, and environmental sustainability. Microorganism-synthesized Ag-containing nanomaterials offer distinct advantages, especially for various surface modification, which potentially fulfill these objectives. In this study, we present the synthesis of silver-selenium (Bio-Ag2Se) nanoparticles using a yeast strain, Rhodotorula mucilaginosa PA-1. These Bio-Ag2Se nanoparticles have small size with a narrow size distribution (12.3 ± 2.9 nm) and long-term stability. They demonstrate a broad antimicrobial spectrum and high antimicrobial efficacy at very low concentrations, effectively targeting microorganisms including Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, as well as pathogenic fungus Candida albicans. Furthermore, Bio-Ag2Se nanoparticles exhibit excellent efficacy to inhibit and eliminate biofilms formed by notorious pathogen S. aureus. In contrast, Bio-Ag2Se nanoparticles at effective antibacterial concentrations demonstrate favorable biocompatibility and do not show obvious cytotoxic effects on human and plant cells. To elucidate the antibacterial mechanisms of Bio-Ag2Se nanoparticles against S. aureus and E. coli, transcriptomic analysis and phenotypic examination were employed. The results reveal significant and broad up-regulation in carbon metabolism pathways in both S. aureus and E. coli, suggesting it as one of the major antibacterial mechanisms of Bio-Ag2Se. This study presents a green synthesis strategy for Ag-containing nanoparticles with promising applications.


Subject(s)
Anti-Infective Agents , Metal Nanoparticles , Humans , Silver/pharmacology , Staphylococcus aureus/metabolism , Escherichia coli/metabolism , Anti-Infective Agents/metabolism , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests
5.
Nat Commun ; 14(1): 7249, 2023 11 09.
Article in English | MEDLINE | ID: mdl-37945565

ABSTRACT

The gut microbiome and its metabolites are increasingly implicated in several cardiovascular diseases, but their role in human myocardial infarction (MI) injury responses have yet to be established. To address this, we examined stool samples from 77 ST-elevation MI (STEMI) patients using 16 S V3-V4 next-generation sequencing, metagenomics and machine learning. Our analysis identified an enriched population of butyrate-producing bacteria. These findings were then validated using a controlled ischemia/reperfusion model using eight nonhuman primates. To elucidate mechanisms, we inoculated gnotobiotic mice with these bacteria and found that they can produce beta-hydroxybutyrate, supporting cardiac function post-MI. This was further confirmed using HMGCS2-deficient mice which lack endogenous ketogenesis and have poor outcomes after MI. Inoculation increased plasma ketone levels and provided significant improvements in cardiac function post-MI. Together, this demonstrates a previously unknown role of gut butyrate-producers in the post-MI response.


Subject(s)
Myocardial Infarction , ST Elevation Myocardial Infarction , Humans , Animals , Mice , Butyrates/metabolism , Heart , Ketone Bodies
6.
Curr Cardiol Rep ; 25(5): 325-331, 2023 05.
Article in English | MEDLINE | ID: mdl-37074564

ABSTRACT

PURPOSE OF REVIEW: Heart failure leads to high mortality. The failing myocardium cannot often be rescued as heart regeneration is mostly compromised by disease progress. Stem cell therapy is a strategy under development to replace the impaired myocardium for recovery after heart injury. RECENT FINDINGS: Many studies have provided evidence of the beneficial effects of pluripotent stem cell-derived cardiomyocyte (CM) implantation into diseased rodent hearts, but there are still many challenges and limitations to replicating the same effects in large animal models for preclinical validation. In this review, we summarize progress in the use of pluripotent stem cell-derived CMs in large animal models based on three key parameters: species selection, cell source, and delivery. Most importantly, we discuss the current limitations and challenges that need to be solved to advance this technology to the translational stage.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Animals , Humans , Myocytes, Cardiac , Models, Animal , Regeneration , Cell Differentiation , Disease Models, Animal
7.
Phys Chem Chem Phys ; 25(5): 3780-3788, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36644933

ABSTRACT

Hydrogen transfer (HT) is of crucial importance in biochemistry and atmospheric chemistry. Here, HT processes involved in the dissociation reaction of dimethyl disulfide radical cations (DMDS˙+, CH3SSCH3˙+) are investigated using quantum chemical calculations. Four HTs from the C to S atom and one HT from the S to S atom are observed and the most probable paths are proposed in the dissociation channel from DMDS˙+ to CHnS+ (n = 2-4). The mechanisms of all these five HTs are described as hydrogen atom transfer (HAT) and four of them are accompanied by electron transfer (ET). Considering the catalytic effect of water molecules existing in organisms and the atmosphere, five HT processes in the dissociation of the [DMDS + H2O]˙+ complex are further explored, which show lower free energy barriers. With the participation of water molecules acting as a base, two HTs from the C to the S atom, which have the largest decrease in energy barriers, are characterized as concerted proton-coupled electron transfer (cPCET). These results can be extended to understand the mechanism of the HT process during the dissociation of disulfide and help provide a strategy to design a rare cPCET mechanism for the activation of the C-H bond.

8.
Neural Regen Res ; 18(3): 587-593, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36018182

ABSTRACT

Mild cognitive impairment (MCI) is a prodrome of Alzheimer's disease pathology. Cognitive impairment patients often have a delayed diagnosis because there are no early symptoms or conventional diagnostic methods. Exosomes play a vital role in cell-to-cell communications and can act as promising biomarkers in diagnosing diseases. This study was designed to identify serum exosomal candidate proteins that may play roles in diagnosing MCI. Mass spectrometry coupled with tandem mass tag approach-based non-targeted proteomics was used to show the differentially expressed proteins in exosomes between MCI patients and healthy controls, and these differential proteins were validated using immunoblot and enzyme-linked immunosorbent assays. Correlation of cognitive performance with the serum exosomal protein level was determined. Nanoparticle tracking analysis suggested that there was a higher serum exosome concentration and smaller exosome diameter in individuals with MCI compared with healthy controls. We identified 69 exosomal proteins that were differentially expressed between MCI patients and healthy controls using mass spectrometry analysis. Thirty-nine exosomal proteins were upregulated in MCI patients compared with those in control patients. Exosomal fibulin-1, with an area under the curve value of 0.81, may be a biomarker for an MCI diagnosis. The exosomal protein signature from MCI patients reflected the cell adhesion molecule category. In particular, higher exosomal fibulin-1 levels correlated with lower cognitive performance. Thus, this study revealed that exosomal fibulin-1 is a promising biomarker for diagnosing MCI.

9.
Theranostics ; 12(17): 7390-7403, 2022.
Article in English | MEDLINE | ID: mdl-36438478

ABSTRACT

Rationale: Gut microbiota plays a crucial role in cancer development and treatment. Studies show that although the gut microbiota is able to promote tumor growth, its presence also improves the efficacy of cancer treatment such as immunotherapy. To date, understanding of the potential impact of the gut microbiota on other treatment modalities such as cancer nanomedicine is still limited. In this study, we aimed to establish the relationship between gut microbiota and cancer nanomedicine, which can potentially open a new path in cancer treatment that combines gut microbiota modulation along with nanotherapeutics. Methods: Mice bearing 4T1 triple-negative breast cancer cells were subjected to gut microbiota modulation by antibiotics (ABX) treatment in the drinking water. Mice given normal water was used for control. The effects of ABX treatment towards gut bacteria was studied by RT-qPCR and 16S next generation sequencing of fecal samples. The mice were then subjected to liposomal doxorubicin (LipoDox) treatment and the amount of nanotherapeutics that accumulated in the tumors was quantified. For therapeutic efficacy, the mice were subjected to ABX treatment and given three injections of LipoDox or saline, while the tumor growth was monitored throughout. Results: Analysis of fecal bacterial content showed that ABX treatment resulted in depletion of gut microbiota. Quantification of LipoDox content revealed significantly increased accumulation in ABX tumor compared to control. Compared to LipoDox treatment alone, we found that combined gut microbiota depletion and LipoDox treatment resulted in augmented long-term anti-tumor efficacy and significantly improved median survival compared to LipoDox only (control vs ABX = 58.5 vs 74 days, p = 0.0002, n = 10 for both groups), with two mice surviving until the end of the experimental end point without experiencing relapse. We also identified the increase in vascular permeability of ABX-treated tumors correlated to for improved therapeutic efficacy and outcome. Conclusion: We showed that gut microbiota depletion led to enhanced tumor vascular permeability, which allowed a larger amount of LipoDox nanoparticles to accumulate in the tumor, leading to better long-term effects. Our results suggest that gut microbiota modulation may be exploited in combination with available nanomedicine-based therapeutics to improve cancer diagnosis, therapeutic efficacy and outcome.


Subject(s)
Gastrointestinal Microbiome , Nanomedicine , Mice , Animals , Neoplasm Recurrence, Local , Doxorubicin
10.
Circulation ; 146(25): 1950-1967, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36420731

ABSTRACT

BACKGROUND: Cardiac regeneration after injury is limited by the low proliferative capacity of adult mammalian cardiomyocytes (CMs). However, certain animals readily regenerate lost myocardium through a process involving dedifferentiation, which unlocks their proliferative capacities. METHODS: We bred mice with inducible, CM-specific expression of the Yamanaka factors, enabling adult CM reprogramming and dedifferentiation in vivo. RESULTS: Two days after induction, adult CMs presented a dedifferentiated phenotype and increased proliferation in vivo. Microarray analysis revealed that upregulation of ketogenesis was central to this process. Adeno-associated virus-driven HMGCS2 overexpression induced ketogenesis in adult CMs and recapitulated CM dedifferentiation and proliferation observed during partial reprogramming. This same phenomenon was found to occur after myocardial infarction, specifically in the border zone tissue, and HMGCS2 knockout mice showed impaired cardiac function and response to injury. Finally, we showed that exogenous HMGCS2 rescues cardiac function after ischemic injury. CONCLUSIONS: Our data demonstrate the importance of HMGCS2-induced ketogenesis as a means to regulate metabolic response to CM injury, thus allowing cell dedifferentiation and proliferation as a regenerative response.


Subject(s)
Myocardial Infarction , Myocytes, Cardiac , Mice , Animals , Myocytes, Cardiac/metabolism , Heart , Myocardium/metabolism , Mice, Knockout , Regeneration/genetics , Cell Proliferation , Mammals
11.
J Control Release ; 352: 879-892, 2022 12.
Article in English | MEDLINE | ID: mdl-36370875

ABSTRACT

Ischemic diseases including myocardial infarction (MI) and limb ischemia are some of the greatest causes of morbidity and mortality worldwide. Cell therapy is a potential treatment but is usually limited by poor survival and retention of donor cells injected at the target site. Since much of the therapeutic effects occur via cell-secreted paracrine factors, including extracellular vesicles (EVs), we developed a porous material for cell encapsulation which would improve donor cell retention and survival, while allowing EV secretion. Human donor cardiac mesenchymal cells were used as a model therapeutic cell and the encapsulation system could sustain three-dimensional cell growth and secretion of therapeutic factors. Secretion of EVs and protective growth factors were increased by encapsulation, and secreted EVs had hypoxia-protective, pro-angiogenic activities in in vitro assays. In a mouse model of limb ischemia the implant improved angiogenesis and blood flow, and in an MI model the system preserved ejection fraction %. In both instances, the encapsulation system greatly extended donor cell retention and survival compared to directly injected cells. This system represents a promising therapy for ischemic diseases and could be adapted for treatment of other diseases in the future.


Subject(s)
Exosomes , Extracellular Vesicles , Mesenchymal Stem Cells , Myocardial Infarction , Animals , Mice , Humans , Exosomes/metabolism , Cell Encapsulation , Porosity , Mesenchymal Stem Cells/metabolism , Extracellular Vesicles/metabolism , Ischemia/therapy , Myocardial Infarction/therapy , Myocardial Infarction/metabolism , Disease Models, Animal
12.
Angew Chem Int Ed Engl ; 61(52): e202208831, 2022 12 23.
Article in English | MEDLINE | ID: mdl-36202761

ABSTRACT

A direct strategy for the difunctionalization of alkenes, with acylation occurring at the more substituted alkene position, would be attractive for complex ketone synthesis. We report herein a reaction driven by a single photocatalyst that enables α-acylation in this way with the introduction of a fluoromethyl, alkyl, sulfonyl or thioether group at the ß-position of the alkene with high chemo- and regioselectivity under extremely mild conditions. Crucial to the success of this method are rate differences in the kinetics of radical generation through single-electron transfer (SET) between different radical precursors and the excited photocatalyst (PC*). Thus, the ß-position of the alkene is first occupied by the group derived from the radical precursor that can be generated most readily, and α-keto acids could be used as an electrophilic reagent for the α-acylation of alkenes.


Subject(s)
Alkenes , Catalysis , Acylation , Indicators and Reagents
13.
J Am Chem Soc ; 144(36): 16667-16675, 2022 09 14.
Article in English | MEDLINE | ID: mdl-36047993

ABSTRACT

Singlet oxygen (1O2)-mediated oxidation represents an attractive strategy for incorporation of oxygen atoms from air under mild and environmentally benign conditions. However, the 1O2 reaction with enamine suffers from fragmentation, leading to very unsuccessful transformation. Here, Lewis acid is introduced to intercept [2 + 2] or "ene" reaction intermediates of the 1O2 reaction and enables oxidative dimerization of enamines to produce pyrrolin-4-ones in good to excellent yields. Mechanistic studies reveal the formation of the imino ketone intermediate from the interaction of 1O2 and enamine, which is able to interact with Lewis acid, relaying the 1O2 reaction in enamine chemistry. For the first time, selective cross-dimerization of two different enamines is achieved. Due to the advantages of mild conditions, high chemoselectivity, and up to 99% yield, a promising strategy has been developed for synthesizing aza-heterocycles under ambient conditions, which can be further applied for the synthesis of imidazolone, quinoxaline, and highly functionalized imine.


Subject(s)
Lewis Acids , Singlet Oxygen , Dimerization , Imines , Oxidation-Reduction
14.
Biomaterials ; 289: 121807, 2022 10.
Article in English | MEDLINE | ID: mdl-36166894

ABSTRACT

We hypothesized that the host microbiome may influence foreign body responses following biomaterial implantation. To test this, we implanted a variety of clinically relevant biomaterials into germ-free or antibiotic-treated mice. Surprisingly, these mice displayed less fibrous tissue deposition, reduced host cell recruitment to the implant site, and differential expression of angiogenic and inflammatory markers. These observations were reversed upon fecal microbiome reconstitution, confirming a causal role of the host microbiome. In a clinically relevant disease model, microbiome-depleted mice cleared hyaluronic acid and bone marrow mononuclear cells from ischemic hind limb tissues more slowly, resulting in an improved therapeutic response. Findings were confirmed in pigs which showed reduced fibrotic responses to a variety of implanted materials. Lastly, we profiled changes in the host microbiome following material implantation, implicating several key bacteria phyla.


Subject(s)
Biocompatible Materials , Gastrointestinal Microbiome , Animals , Anti-Bacterial Agents , Foreign-Body Reaction , Hyaluronic Acid , Mice , Swine
15.
Angew Chem Int Ed Engl ; 61(40): e202209293, 2022 10 04.
Article in English | MEDLINE | ID: mdl-35912895

ABSTRACT

Herein, cobaloxime is used for the first time as a catalyst for the synthesis of phosphorylated heteroaromatics, which is an intriguing and versatile functional motif. With visible-light irradiation, cobaloxime not only oxidizes phosphine oxides to form phosphorus radicals (P-radicals) for a subsequent reaction with radical acceptor isocyanides or heteroaromatics, but also combines the radical intermediate with ß-H elimination, thereby producing phosphorylated heteroaromatics with only H2 or CH4 as byproduct. Phosphine oxides with dialkyl, alkylaryl, and diaryl substituents could be directly transformed into phosphorylated phenanthridines, benzothiazoles, isoquinolines, and common heteroaromatics. This catalytic system features extremely mild conditions, broad substrate scope and good to excellent yields. Scale-up reaction and sunlight reaction show the great application potential in the green synthesis of important organophosphorus chemicals.


Subject(s)
Cyanides , Oxides , Benzothiazoles , Isoquinolines , Organometallic Compounds , Phenanthridines , Phosphines , Phosphorus
16.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 20.
Article in English | MEDLINE | ID: mdl-35745684

ABSTRACT

Since December 2019, the novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected ~435 million people and caused ~6 million related deaths as of March 2022. To combat COVID-19, there have been many attempts to repurpose FDA-approved drugs or revive old drugs. However, many of the current treatment options have been known to cause adverse drug reactions. We employed a population-based drug screening platform using 13 human leukocyte antigen (HLA) homozygous human induced pluripotent cell (iPSC) lines to assess the cardiotoxicity and neurotoxicity of the first line of anti-COVID-19 drugs. We also infected iPSC-derived cells to understand the viral infection of cardiomyocytes and neurons. We found that iPSC-derived cardiomyocytes express the ACE2 receptor which correlated with a higher infection of the SARS-CoV-2 virus (r = 0.86). However, we were unable to detect ACE2 expression in neurons which correlated with a low infection rate. We then assessed the toxicity of anti-COVID-19 drugs and identified two cardiotoxic compounds (remdesivir and arbidol) and four neurotoxic compounds (arbidol, remdesivir, hydroxychloroquine, and chloroquine). These data show that this platform can quickly and easily be employed to further our understanding of cell-specific infection and identify drug toxicity of potential treatment options helping clinicians better decide on treatment options.

17.
Cell Rep ; 39(1): 110643, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35385754

ABSTRACT

In this study, we establish a population-based human induced pluripotent stem cell (hiPSC) drug screening platform for toxicity assessment. After recruiting 1,000 healthy donors and screening for high-frequency human leukocyte antigen (HLA) haplotypes, we identify 13 HLA-homozygous "super donors" to represent the population. These "super donors" are also expected to represent at least 477,611,135 of the global population. By differentiating these representative hiPSCs into cardiomyocytes and neurons we show their utility in a high-throughput toxicity screen. To validate hit compounds, we demonstrate dose-dependent toxicity of the hit compounds and assess functional modulation. We also show reproducible in vivo drug toxicity results using mouse models with select hit compounds. This study shows the feasibility of using a population-based hiPSC drug screening platform to assess cytotoxicity, which can be used as an innovative tool to study inter-population differences in drug toxicity and adverse drug reactions in drug discovery applications.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Induced Pluripotent Stem Cells , Animals , Cardiotoxicity , Cell Differentiation , Cells, Cultured , Humans , Mice , Myocytes, Cardiac , Neurons
18.
Microorganisms ; 9(11)2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34835442

ABSTRACT

YgfY(SdhE/CptB) is highly conserved while has controversial functions in bacteria. It works as an antitoxin and composes a type IV toxin-antitoxin system with YgfX(CptA) typically in Escherichia coli, while functions as an flavinylation factor of succinate dehydrogenase and fumarate reductase typically in Serratia sp. In this study, we report the contribution of YgfY in Shewanella oneidensis MR-1 to tolerance of low temperature and nitrite. YgfY deficiency causes several growth defects of S. oneidensis MR-1 at low temperature, while YgfX do not cause a growth defect or morphological change of S. oneidensis MR1-1 and E. coli. YgfY do not interact with FtsZ and MreB nor with YgfX examined by bacterial two-hybrid assay. YgfY effect on growth under low temperature is not attributed to succinate dehydrogenase (SDH) because a mutant without SDH grows comparably with the wild-type strain in the presence of succinate. The ygfY mutant shows impaired tolerance to nitrite. Transcription of nitrite reductase and most ribosome proteins is significantly decreased in the ygfY mutant, which is consistent with the phenotypes detected above. Effects of YgfY on growth and nitrite tolerance are closely related to the RGXXE motif in YgfY. In summary, this study demonstrates pleiotropic impacts of YgfY in S. oneidensis MR-1, and sheds a light on the physiological versatility of YgfY in bacteria.

19.
Exp Ther Med ; 22(6): 1364, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34659510

ABSTRACT

Chemoresistance is the primary cause of the poor outcome of glioblastoma multiforme (GBM) therapy. Leucine-rich repeat-containing G-protein coupled receptor 6 (LGR6) is involved in the growth and proliferation of several types of cancer, including gastric cancer and ovarian cancer. Therefore, the aim of the present study was to investigate the role of LGR6 in GBM malignancy and chemoresistance. Cell counting kit-8 and Matrigel®-Transwell assays were conducted to assess GBM cell viability and invasion. The effect of LGR6 on cell cycle progression and activation of Akt signaling was analyzed by performing propidium iodide staining and western blotting, respectively. The results demonstrated that LGR6, a microRNA-1236-3p target candidate, promoted GBM cell viability and invasion, and mediated temozolomide sensitivity in SHG-44 and U251 GBM cells. In addition, LGR6 triggered the activation of the Akt signaling pathway during GBM progression. Collectively, the results of the present study suggested that LGR6 promoted GBM malignancy and chemoresistance, at least in part, by activating the Akt signaling pathway. The results may aid with the identification of a novel therapeutic target and strategy for GBM.

20.
Org Lett ; 23(20): 8082-8087, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34609892

ABSTRACT

An aerobic metal-free, visible-light-induced regioselective thiolation of phenols with thiophenols is reported. The cross-coupling protocol exhibits great functional group tolerance and high regioselectivity. Mechanistic studies reveal that the disulfide radical cation plays a crucial role in the visible-light catalysis of aerobic thiolation. Simply controlling the equivalent ratio of substrates enables the selective formation of sulfide or sulfoxide products with high activity in a one-pot reaction.

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