Diastereodivergent and Regioselective Synthesis of Tetrahydrofuro[2,3-b]furans with Four Consecutive Stereocenters.

Base-catalyzed diastereodivergent and regioselective domino processes of triketone enones with arylacetaldehydes for the synthesis of tetrahydrofuro[2,3-b]furans with four consecutive stereocenters are reported. Good yields and diastereoselectivities are obtained when DBU is employed as a catalyst; in contrast, Et3N delivers a different diastereomer in excellent diastereoselectivity. This work offers many advantages, including switchable diastereoselectivity, cheap base catalysts, and a simple operation.

Diagnostic value of lncRNA NORAD in pulmonary tuberculosis and its regulatory role in Mycobacterium tuberculosis infection of macrophages.

Pulmonary tuberculosis (PTB) infection is a chronic inflammatory response caused by Mycobacterium tuberculosis (Mtb). The purpose of this study was to confirm the value of long noncoding RNA NORAD (noncoding RNA activated by DNA damage) in the diagnosis of PTB and to explore its mechanism in Mtb-infected macrophages. NORAD serum levels were estimated by qRT-PCR in 90 patients with PTB and 85 healthy individuals. Receiver operating characteristic curves were plotted to assess the diagnostic value of NORAD in PTB. Human and murine macrophages were infected with Mtb strain H37Rv. CCK-8 (a cell counting kit) and ELISA detected viability of macrophages and inflammatory cytokine secretion, respectively. A dual-luciferase reporter assay was performed to analyze the relationship between NORAD and microRNA (miR)-618. NORAD was significantly elevated in patients with PTB, and its positivity was correlated with levels of inflammatory cytokines IL-1 ß (r = 0.854), TNF-α (r = 0.617), and IL-6 (r = 0.585). With an area under the curve of 0.918, and sensitivity and specificity of 80.0% and 89.4%, respectively, NORAD remarkedly differentiated patients with PTB from healthy individuals. Furthermore, Mtb infection significantly increased NORAD levels in THP-1 and RAW264.7 cells and increased their viability and inflammation (P < 0.001). However, this increased effect was weakened by reduced NORAD levels. Dual-luciferase reporter assay results confirmed that miR-618 in macrophages is a target miRNA for NORAD and can be negatively regulated by it. Moreover, elevated miR-618 suppressed macrophage viability and inflammation in Mtb infection. NORAD is a potential diagnostic biomarker for PTB and is involved in Mtb-infected macrophage activity and inflammation by targeting miR-618.

Comparison of clinical and imaging features between pulmonary tuberculosis complicated with lung cancer and simple pulmonary tuberculosis: a systematic review and meta-analysis.

This review aimed to compare the clinical features and CT imaging features between patients with pulmonary tuberculosis (PTB) and lung cancer and patients with PTB alone. That would help to analyse the differences between the two and consequently providing a theoretical basis for the clinical diagnosis and treatment for the patients. Relevant case-control studies focusing on the clinical and CT imaging characteristics between PTB with lung cancer and PTB alone were systematically searched from five electronic databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for comparison. As of 2021-07-06, a total of 1735 articles were retrieved. But only 15 articles were finally included for meta-analysis. The results showed a higher proportion of irritable cough, haemorrhagic pleural effusion and lower proportion of night sweating in PTB patients with lung cancer than in PTB patients, and the differences were statistically significant (irritable cough: OR 2.43, 95% CI 1.43-4.11; haemorrhagic pleural effusion: OR 5.73, 95% CI 1.63-20.12; night sweating: OR 0.56, 95% CI 0.36-0.87). In addition, there are many differences in the imaging characteristics of the two types of patients. In conclusion, this review summarises the similarities and differences in clinical symptoms and imaging features between patients with PTB and lung cancer and patients with PTB alone, suggesting that we should be alert to the occurrence of lung cancer in patients with obsolete PTB relapse.

The Effects of Cellulose on AOM/DSS-Treated C57BL/6 Colorectal Cancer Mice by Changing Intestinal Flora Composition and Inflammatory Factors.

Chronic intestinal inflammation is a key risk factor of colorectal cancer (CRC). It is known that microbial dysbiosis induces increased inflammatory factors which promote tumorigenesis and cellulose can be beneficial to CRC. In the present study, we investigated the regulatory effects of cellulose on intestinal flora composition and colorectal carcinogenesis in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CRC mouse model. Supplementation of cellulose significantly attenuated inflammation and tumor formation in AOM/DSS-treated CRC mice. The survival rate and the tumor inhibition rate were higher in the medium-dose cellulose group (MCEG) and high-dose cellulose group (HCEG) than in the model group (MG; P < 0.05). Cellulose supplementation stimulated shifts in the intestinal flora in AOM/DSS-treated CRC mice. Additionally, levels of inflammatory mediators involved in colorectal carcinogenesis, such as IL-6, IL-1ß, and TNF-α, were lower in the serum of the low-dose cellulose group, MCEG, and HCEG when compared with the MG (P < 0.05). Whereas the abundance of differential bacteria was correlated with the concentration of IL-6, IL-1ß, and TNF-α. These results showed cellulose changed the composition of intestinal flora and inhibited colon inflammation and neoplasm formation caused by the AOM/DSS treatment.

Biphasic effects of ethanol consumption on N,N-dimethylformamide-induced liver injury in mice.

N,N-Dimethylformamide (DMF) is a well-documented occupational hazardous material, which can induce occupational liver injury. The current study was designed to investigate whether ethanol consumption can affect DMF-induced hepatotoxicity and the potential underlying mechanisms involved. We found that a single dose of ethanol (1.25, 2.5, or 5 g/kg bw by gavage) significantly repressed the increase in serum alanine transaminase (ALT) and aspartate transaminase (AST) activities and alleviated the liver histopathological changes in mice challenged with 3 g/kg DMF. In contrast, long-term moderate drinking (2.5 g/kg bw) significantly aggravated the repeated DMF (0.7 g/kg bw) exposure-induced increase in the serum ALT and AST activities. Mechanistically, acute ethanol consumption suppressed DMF-induced activation of the NLR family pyrin domain-containing protein 3 (NLRP3) inflammasome, while long-term moderate ethanol consumption promoted hepatocyte apoptosis in the mouse liver. Notably, cytochrome P4502E1 (CYP2E1) protein level and activity in mouse livers were not significantly affected by ethanol per se in the two models. These results confirm that regular drinking can increase the risk of DMF-induced hepatotoxicity, and suggest that DMF-handling workers should avoid consuming ethanol to reduce the risk of DMF-indued liver injury.

The changes and its significance of peripheral blood NK cells in patients with tuberculous meningitis.

Objective: Tuberculous meningitis (TBM) is the most severe form of tuberculosis (TB). The purpose of this study was to explore the relationship between the number of natural killer (NK) cells and adaptive immune status, and disease severity in TBM patients. Methods: We conducted a retrospective study on 244 TB patients and 146 healthy control subjects in the 8th Medical Center of the PLA General Hospital from March 2018 and August 2023. Results: The absolute count of NK cells in the peripheral blood of TBM patients was significantly lower than that in normal controls (NC), latent tuberculosis infection (LTBI), and non-severe TB (NSTB) patients (p < 0.05). The proportion of TBM patients (48.7%) with a lower absolute count of NK cells than the normal reference value was significantly higher than that in NC (5.2%) and LTBI groups (4.0%) (p < 0.05), and slightly higher than that in NSTB group (36.0%) (p > 0.05). The absolute counts of lymphocyte subsets in TBM combined with other active TB group, etiology (+) group, IGRA (-) group, and antibody (+) group were lower than that in simple TBM group, etiology (-) group, IGRA (+) group, and antibody (-) group, respectively. The CD3+ T, NK, and B cells in BMRC-stage III TBM patients were significantly lower than those in stage I and stage II patients (p < 0.05). The counts of CD3+ T, CD4+ T, and B cells in the etiology (+) group were significantly lower than those in the etiology (-) group (p < 0.05). Conclusion: The absolute counts of lymphocyte subsets in the peripheral blood of TBM patients were significantly decreased, especially in NK cells. The reduction of these immune cells was closely related to the disease severity and had a certain correlation with cellular and humoral immune responses. This study helps to better understand the immune mechanism of TBM and provides reliable indicators for evaluating the immune status of TBM patients in clinical practice.

In vitro activities of contezolid (MRX-I) against drug-sensitive and drug-resistant Mycobacterium tuberculosis.

A novel oxazolidinone for the treatment of Mycobacterium tuberculosis has been developed, but the activity of contezolid (MRX-I) still needs to be clarified. In this study, we isolated Mycobacterium tuberculosis from 48 clinical patients with pulmonary tuberculosis. Roche drug susceptibility tests identified drug-sensitive and 39 drug-resistant M. tuberculosis isolates. Drug susceptibility assays indicated that MRX-I exhibited anti-Mycobacterium tuberculosis activity against both drug-sensitive and drug-resistant isolates, with an advantage against drug-resistant isolates. The results also showed that the anti-Mycobacterium tuberculosis activity was comparable to that of linezolid. IMPORTANCE Currently, Mycobacterium tuberculosis has exhibited increased drug resistance, leading to ineffective drug treatment in many patients with tuberculosis. Among the anti-Mycobacterium tuberculosis drugs, oxazolidinones have been gradually developed. Contezolid (MRX-I) has been newly developed in China with advantages versus the first oxazolidinone antibiotic approved by the Food and Drug Administration for clinical use, but the anti-M. tuberculosis activity needs to be further clarified. In this study, in vitro activities of MRX-I against M. tuberculosis were tested. The drug susceptibility assays indicated that MRX-I exhibited anti-M. tuberculosis activity comparable to that of linezolid, with an advantage against drug-resistant isolates.

Building a model for the differential diagnosis of non-tuberculous mycobacterial lung disease and pulmonary tuberculosis: A case-control study based on immunological and radiological features.

BACKGROUND: Although the incidence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing annually, it is easily misdiagnosed as pulmonary tuberculosis (PTB). This study aimed to screen and identify the immunological and radiological characteristics that differentiate NTM-PD from PTB and to construct a discriminatory diagnostic model for NTM-PD, providing new tools for its differential diagnosis. METHODS: Hospitalised patients diagnosed with NTM-PD or PTB between January 2019 and June 2023 were included in the study. Immunological and radiological characteristics were compared between the two groups. Based on the selected differential features, a logistic regression algorithm was used to construct a discriminatory diagnostic model for NTM-PD, and its diagnostic performance was preliminarily analysed. RESULTS: Patients with NTM-PD were significantly older than those with PTB and the tuberculosis-specific interferon-gamma release assay (TB-IGRA) positivity rate was significantly lower in the NTM-PD group. Moreover, the absolute counts of total T lymphocytes, CD4+ T lymphocytes, CD8+ T lymphocytes, NK cells, and B lymphocytes were significantly lower in patients with NTM-PD and PTB than in healthy controls. Additionally, patients with NTM-PD had a significantly lower absolute count of B lymphocytes than the PTB group. Radiological analysis revealed significant differences between patients with NTM-PD and PTB in terms of cavity wall thickness, bronchial dilation, lung consolidation, pulmonary nodule size, pulmonary emphysema, lung bullae, lymph node calcification, pleural effusion, mediastinal and hilar lymphadenopathy, and the tree-in-bud sign. Bronchial dilation was identified as the predominant risk factor of NTM-PD, whereas TB-IGRA positivity, lymph node calcification, pleural effusion, and mediastinal and hilar lymphadenopathies were protective factors. Based on this, we constructed a discriminatory diagnostic model for NTM-PD. Its receiver operating characteristic curve demonstrated good diagnostic performance, with an area under the curve of 0.938. At the maximum Youden index of 0.746, the sensitivity and specificity were 0.835 and 0.911, respectively. CONCLUSIONS: Patients with NTM-PD and PTB exhibited impaired humoral and cellular immune functions as well as significant differences in radiological features. The constructed NTM-PD diagnostic model demonstrated good diagnostic performance. This study provides a new tool for the differential diagnosis of NTM-PD.

Diversity-Oriented Catalytic Asymmetric Dearomatization of Indoles with o-Quinone Diimides.

Herein, the first diversity-oriented catalytic asymmetric dearomatization of indoles with o-quinone diimides (o-QDIs) is reported. The catalytic asymmetric dearomatization (CADA) of indoles is one of the research focuses in terms of the structural and biological importance of dearomatized indole derivatives. Although great achievements have been made in target-oriented CADA reactions, diversity-oriented CADA reactions are regarded as more challenging and remain elusive due to the lack of synthons featuring multiple reaction sites and the difficulty in precise control of chemo-, regio-, and enantio-selectivity. In this work, o-QDIs are employed as a versatile building block, enabling the chemo-divergent dearomative arylation and [4 + 2] cycloaddition reactions of indoles. Under the catalysis of chiral phosphoric acid and mild conditions, various indolenines, furoindolines/pyrroloindolines, and six-membered-ring fused indolines are collectively prepared in good yields with excellent enantioselectivities. This diversity-oriented synthesis protocol enriches the o-quinone chemistry and offers new opportunities for CADA reactions.

Long non-coding RNA SNHG16 silencing inhibits proliferation and inflammation in Mycobacterium tuberculosis-infected macrophages by targeting miR-140-5p expression.

OBJECTIVE: The study investigated the clinical diagnostic value of long non-coding RNA (LncRNA) small nucleolar RNA host gene 16 (SNHG16) and explored its underlying molecular mechanism through Mycobacterium tuberculosis (M. tuberculosiinfection of macrophages. METHODS: RT-qPCR analysis of the serum SNHG16 levels of the 66 healthy individuals, 67 latent TB (LTB) patients, and 67 active TB (ATB) patients. The receiver-operating characteristic (ROC) curve to detect the clinical diagnostic value of SNHG16 in TB patients. In vitro, M. tuberculosis-infected macrophages, CCK-8 and ELISA to detect cell proliferation and inflammatory factor levels. Luciferase reported assay was performed to analyze the targeting relationship between SNHG16 and miR-140-5p. RESULTS: SNHG16 was significantly elevated in TB patients, and among them, ATB patients were higher than LTB patients. ROC confirmed that SNHG16 could distinguish LTB patients from healthy controls, and ATB patients from LTB patients, and can be used as a good diagnostic biomarker for TB. M. tuberculosis infection increased SNHG16 levels and promoted the proliferation and inflammation in macrophages. However, SNHG16 silencing significantly reversed the effect of infection. miR-140-5p, a direct target miRNA of SNHG16, was down-regulated in TB patients and was negatively correlated with SNHG16. When miR-140-5p was inhibited, the alleviating effect of SNHG16 silencing on M. tuberculosis infection proliferation and inflammation was significantly reversed. CONCLUSION: The present results suggested that SNHG16 may be a new diagnostic biomarker for TB patients and SNHG16 silencing may alleviate TB by inhibiting the proliferation of macrophages in TB by regulation miR-140-5p.

Protease Biosensor by Conversion of a Homogeneous Assay into a Surface-Tethered Electrochemical Analysis Based on Streptavidin-Biotin Interactions.

This work proposed a new sensing strategy for protease detection by converting a homogeneous assay into a surface-tethered electrochemical analysis. Streptavidin (SA), a tetramer protein, was used as the sensing unit based on the SA-biotin coupling chemistry. Caspase-3 was used as the model analyte, and a biotinylated peptide with a sequence of biotin-GDEVDGK-biotin was designed as the substrate. Specifically, the peptide substrate could induce an assembly of SA to form (SA-biotin-GDEVDGK-biotin)n aggregates through SA-biotin interactions, which was confirmed by atomic force microscopy (AFM). The peptide substrate-induced assembly of SA was facilely initiated on an electrode-liquid surface by modification of the electrode with SA. The in situ formation of (SA-biotin-GDEVDGK-biotin)n aggregates created an insulating layer, thus limiting the electron transfer of ferricyanide. Once the peptide substrate was cleaved into two shorter fragments (biotin-GDEVD and GK-biotin) by caspase-3, the resulting products would compete with biotin-GDEVDGK-biotin to bind SA proteins immobilized on the electrode surface and distributed in a solution, thus preventing the in situ formation of (SA-biotin-GDEVDGK-biotin)n assemblies. With the simple principle of the substrate-induced assembly of SA, a dual-signal amplification was achieved with improved sensitivity. Taking advantage of high sensitivity, simple principle, and easy operation, this method can be augmented to design various surface-tethered biosensors for practical applications.

Combination of Inositol Hexaphosphate and Inositol Inhibits Liver Metastasis of Colorectal Cancer in Mice Through the Wnt/ß-Catenin Pathway.

INTRODUCTION: Colorectal cancer, one of the most common tumors, is mainly fatal because of the occurrence of liver metastasis. Inositol hexaphosphate (IP6) and inositol (INS) were found, both, in vitro and in vivo to play an anti-tumor effect, whereas the combination of IP6 and INS was more effective than IP6 or INS alone. MATERIALS AND METHODS: The inhibitory effects of IP6, INS and the combination of IP6+INS on tumor progression and liver metastasis of colorectal cancer were investigated in an orthotopic transplantation model of colorectal cancer. The tumor-bearing mice were selected by in vivo bioluminescence imaging and were treated with IP6, INS, and IP6 combined with INS, respectively. All mice were sacrificed after 6 weeks of treatment. The cancer development and metastasis were compared among the groups. The expression of genes related to the Wnt/ß-catenin in the model was analyzed. RESULTS: The results demonstrated that liver metastasis was inhibited after treatment with IP6, INS, and IP6+INS. Compared to that of the M_G, survival period was extended, and tumor weight was lowered in IP6_G, INS_G, and IP6+INS_G. Besides, the liver metastatic area of mice in IP6+INS_G was relatively smaller than that in M_G, IP6_G, or INS_G. The results of RNA-seq analysis showed that the expressions of Wnt10b, Tcf7, and c-Myc were significantly downregulated in IP6+INS_G compared to that in M_G (P<0.05). Results of real-time PCR and Western blot showed that mRNA and protein expressions of ß-catenin, Wnt10b, Tcf7, and c-Myc were significantly lower in IP6+INS_G compared to that in M_G (P<0.05). DISCUSSION: IP6+INS was more effective in inhibiting liver metastasis of colorectal cancer than IP6 or INS alone. The better inhibition effect may be accomplished through regulating the mutation of Wnt/ß-catenin signaling pathway by inhibiting Wnt10b, Tcf7, ß-catenin, and c-Myc from abnormally high expression.

[Role of calcineurin-nuclear factor of activated T cells signaling pathway in myoblast apoptosis induced by cyclic tensile strain].

OBJECTIVE: This study investigated the role and mechanism of calcineurin (CaN)-nuclear factor of activated T cells (NFAT) pathway in the myoblast apoptosis induced by cyclic tensile strain. METHODS: Myoblasts were cultured using an in vitro-mechanical stimulation model and imposed with tension for different hours with a multi-channel cell stress loading system. Cyclosporine (CsA) was used as CaN inhibitor to clarify the role of CaN in the apoptosis induced by cyclic stress. Hochest 33258 staining and flow cytometry detection were performed to detect the apoptotic cells. Real-time polymerase chain reaction was conducted to detect the mRNA expression of CaN and NFAT. Protein levels of NFAT3 were evaluated by Western blot. RESULTS: The apoptosis rate increased with the extension of loading time. The mRNA expression of the CaN subunits, CnA and CnB, and the protein levels of NFAT3 also increased. When the myoblasts were incubated with CsA, the apoptosis rate decreased, the mRNA expression of CnA and NFAT3 significantly decreased, and the NFAT3 protein expression levels became significantly lower than those of the groups without CsA. CONCLUSION: Continuous cyclic tensile stress can induce myoblast apoptosis. The CaN-NFAT signaling pathway may be involved in the cyclic stretch-induced apoptosis of myoblasts.