Antiviral Activity of Benzoheterocyclic Compounds from Soil-Derived Streptomyces jiujiangensis NBERC-24992

Pseudorabies virus (PRV) is a pathogen that causes Aujeszky's disease (AD) in animals, leading to huge economic losses to swine farms. In order to discover anti-PRV compounds, we studied the extracts of the strain Streptomyces jiujiangensis NBERC-24992, which showed significant anti-PRV activity. Eight benzoheterocyclic secondary metabolites, including three new compounds (1-3, virantmycins D-G) and five known compounds (4-8, virantmycin, A-503451 D, A-503451 D acetylate, A-503451 A, and A-503451 B), were isolated from the broth of NBERC-24992. The structures of the new compounds were identified by using extensive spectroscopic data, including mass spectrometry (MS), nuclear magnetic resonance (NMR), and electronic circular dichroism (ECD). Compound 1 was found to be a novel heterocyclic compound with a tricyclic skeleton from natural product. All compounds were tested for antiviral activity, and 4 (virantmycin) showed an excellent effect against PRV and was better than ribavirin and acyclovir. Our study revealed that chlorine atom and tetrahydroquinoline skeleton were important active moiety for antiviral activity. Virantmycin could be a suitable leading compound for an antiviral drug against PRV.

Pharmacy student's perceptions, behaviours and attitudes toward virtual reality simulation.

Aims: The definition of virtual reality simulation (VRS) used for study is the recreation of realistic simulation in a fully online situation with an immersive environment for learning an activity. The study aims to evaluate pharmacy students' perspectives, behavioral and attitude characteristics in the process of VRS course requiring practical skills. Materials and methods: This cross-sectional study was based on quantitative questionnaires analysis. A five-point Likert Scale (rating from 1 = Strongly Disagree; 2 = Disagree; 3 = Neutral; 4 = Agree; 5 = Strongly Agree) was utilized to measure the extent to which the students agrees on 30 statements comprised in A-E sections related to VRS. The validity and reliability of the questionnaire were studied by the Cronbach's Alpha calculation. Results: A total of 119 junior and senior pharmacy students, aged 18-25, participated in this study. There is no significant gender difference (P > 0.05) and grade difference (P > 0.05) in mean perception score, mean attitude score, mean behavior score and comparison score respectively. Most pharmacy students had positive perception that VRS could help them in practical ability (61.4 %), autonomous learning (68.9 %) and theoretical knowledge (61.4 %). Nevertheless, less than half the students agreed that VRS courses were indispensable (44.5 %) and needed to be increased (42.9 %). Moreover, the 'disagree' statement (33.6 %) exceeded 'agree' statement (27.7 %) about the question of whether preferring VRS courses to lab teaching. Interestingly, a significant positive correlation that was observed between mean perception score and mean attitude score (r = 0.76, p < 0.001), mean comparison (r = 0.68, p < 0.001) and mean behavior (r = 067, p < 0.001), which revealed that students who thought VRS was beneficial were more likely to accept it. Conclusion: The study highlights the need to establish an interactive, immersive and measurable VRS courses. It is suggested that good interaction between the faculty and student, technology improvement and blended programmatic assessment should be involved in challenges for implementing VRS courses.

An unprecedented ergostane with a 6/6/5 tricyclic 13(14 → 8)abeo-8,14-seco skeleton from Talaromyces adpressus.

Talasterone A (1), an unprecedented 6/6/5 tricyclic 13(14 â†’ 8)abeo-8,14-seco-ergostane steroid, together with two known congeners dankasterone B (2) and (14ß,22E)-9,14-dihydroxyergosta-4,7,22-triene-3,6-dione (3), were characterized from Talaromyces adpressus. The structure of 1 with absolute configuration was elucidated based on NMR spectroscopic data and ECD calculation. Compound 2 belongs to a class of unconventional 13(14 â†’ 8)abeo-ergostanes, which have been renewed via the 1,2-migration of C-13-C-14 bond to C-8. In addition, compound 1 represents the first example of ergostane with a tricyclic 13(14 â†’ 8)abeo-8,14-seco-ergostane skeleton. The proposed biosynthetic pathway was established with the support of the coisolation of the known congeners from the producing organism. It is especially noteworthy that compound 1 exhibited potent anti-inflammatory activity with an IC50 value of 8.73 ± 0.66 µM, inhibiting the NF-κB pathway and thus reducing the production of proinflammatory cytokines.

Secondary Metabolites from Marine-Derived Bacillus: A Comprehensive Review of Origins, Structures, and Bioactivities.

The marine is a highly complex ecosystem including various microorganisms. Bacillus species is a predominant microbialflora widely distributed in marine ecosystems. This review aims to provide a systematic summary of the newly reported metabolites produced by marine-derived Bacillus species over recent years covering the literature from 2014 to 2021. It describes the structural diversity and biological activities of the reported compounds. Herein, a total of 87 newly reported metabolites are included in this article, among which 49 compounds originated from marine sediments, indicating that marine sediments are majority sources of productive strains of Bacillus species Therefore, marine-derived Bacillus species are a potentially promising source for the discovery of new metabolites.

Enhancement of axial resolution and image contrast of a confocal microscope by a microsphere working in noncontact mode.

A new technique, to the best of our knowledge, for improving the axial resolution and imaging contrast of a reflection mode confocal microscope is proposed. A 50 µm silica microsphere is added in front of the objective lens to enhance both the focusing of illumination and the collection of reflected and scattered light from sample surfaces in noncontact mode. An adjustable pinhole is used to compensate the displacement of the focal point in the axial direction. Various samples, including grouped nanolines and nanosteps, are used to demonstrate imaging performance. By comparison to an NA 0.9 commercial confocal microscope, the new setup achieves the axial resolution up to 100 nm and increases the image contrast by 4.56 times. The entire setup offers a cost-effective solution for high imaging performance, which can be applied in many fields from nanotechnology to biology.

Betulin isolated from Pyrola incarnata Fisch. inhibited lipopolysaccharide (LPS)-induced neuroinflammation with the guidance of computer-aided drug design.

This study aims to investigate active phytochemicals isolated from Pyrola incarnata Fisch. (P. incarnata) and their protection against neuroinflammation induced by LPS. Betulin, accompanied with other 9 compounds, were isolated from P. incarnata and elucidated by spectroscopic analysis (1H-, 13C NMR). ELISA kits and the measurement of NO production based on Griess reaction showed that betulin (5) (250 µg/mL) could suppress LPS-induced activation of microglial cell BV-2 better than others by inhibiting inflammatory cytokines (TNF-α, IL-6, IL-1ß) expression and NO production. With the guidance of computer-aided drug design and the analysis of biological experiment, we demonstrated betulin could reduce LPS-induced iNOS expression, prevent JNKs pathways, and down-regulate the phosphorylation levels of NF-κB/p65. In conclusion, betulin isolated from P. incarnata possessed outstanding anti-neuroinflammation potential, presumably related to iNOS expression, JNKs and NF-κB/p65 pathways. Therefore, Pyrola incarnata may be a valuable natural resource and betulin is a potential drug for the treatment of neurodegenerative disorders by inhibiting inflammatory mediators.

Pyrola incarnata demonstrates neuroprotective effects against ß-amyloid-induced memory impairment in mice.

This study aims to investigate the neuroprotective effects of Pyrola incarnata against ß-amyloid-induced memory impairment in mice. Ethanol extract of Pyrola incarnata (EPI) was obtained and led to eleven phytochemicals successfully by isolation and purification, which were elucidated by spectroscopic analysis (1H NMR, 13C NMR and HR-ESI-MS). Thereinto, ursolic acid was gained as most abundant monomer. C57BL/6 mice were intracerebroventricular injected with aggregated Aß25-35. Open-field test, Barnes maze test and Morris water maze were conducted for evaluating cognition processes of EPI and ursolic acid. EPI significantly improved learning and memory deficits, attenuated the Aß25-35 level of deposition immunohistochemically. Further studies revealed that ursolic acid as bioactive phytochemical of P. incarnata improved spatial memory performance and ameliorated Aß25-35 accumulation by activating microglia cells and up-regulating Iba1 level in the hippocampus. These findings suggest P. incarnata could improve the cognition of mice and be a promising natural source for the treatment of neurodegenerative disease.

Structurally Diverse Meroterpenoids from a Marine-Derived Aspergillus sp. Fungus.

Three new meroterpenoids, asperaustins A-C (1-3), and seven known analogues (4-10) were isolated from a marine-derived Aspergillus sp. fungus. The structures and absolute configurations of these new compounds were unequivocally determined by extensive spectroscopic analyses and single-crystal X-ray diffraction analyses. Asperaustin A (1) possesses an unusual spiro[4.5]deca-3,6-dien-2-one moiety with a unique 5/6/6/6/5 pentacyclic skeleton. The absolute configurations of austinoneol A (7) and precalidodehydroaustin (9) were determined by single-crystal X-ray diffraction analyses using Cu Kα radiation for the first time.

A New Macrodiolide and Two New Polycyclic Chromones from the Fungus Penicillium sp. SCSIO041218.

A new macrodiolide, mangrovlide A (1) and two new polycyclic chromones, penixanthones C (2) and D (3), as well as four other known compounds (4-7), have been isolated from the mangrove sediment derived fungus Penicillium sp. SCSIO041218, cultured in the 0.25% NaCl rice substrate. The structures of the new compounds were determined by analysis of the NMR and MS spectroscopic data. Compound 1 possesses a 10-membered macrodiolide unit, while 2 and 3 are chromones with an unprecedented 6/6/6/5 polycyclic skeleton. Compounds 1-7 were evaluated for their cytotoxicities, while all the compounds displayed weak or no activity.

Spirostaphylotrichin X from a Marine-Derived Fungus as an Anti-influenza Agent Targeting RNA Polymerase PB2.

A new spirocyclic γ-lactam, named spirostaphylotrichin X (1), and three related known spirostaphylotrichins (2-4) were isolated from the marine-derived fungus Cochliobolus lunatus SCSIO41401. Their structures were determined by spectroscopic analyses. Spirostaphylotrichin X (1) displayed obvious inhibitory activities against multiple influenza virus strains, with IC50 values from 1.2 to 5.5 µM. Investigation of the mechanism showed that 1 inhibited viral polymerase activity and interfered with the production of progeny viral RNA. Homogeneous time-resolved fluorescence, surface plasmon resonance assays, and a molecular docking study revealed that 1 could inhibit polymerase PB2 protein activity by binding to the highly conserved region of the cap-binding domain of PB2. These results suggest that 1 inhibits the replication of influenza A virus by interfering with the activity of PB2 protein and that 1 represents a new type of potential lead compound for the development of anti-influenza therapeutics.

Antioxidant activity against H2O2-induced cytotoxicity of the ethanol extract and compounds from Pyrola decorate leaves.

CONTEXT: The leaves of Pyrola decorate H. Andr (Pyrolaceae), known as Luxiancao, have long been used for treating kidney deficiency, gastric haemorrhage and rheumatic arthritic diseases in traditional Chinese medicine. OBJECTIVE: The phytochemicals and antioxidant capacities in vitro of P. decorate leaves were investigated. MATERIALS AND METHODS: Ethanol, petroleum ether, acetidin, n-butyl alcohol and aqueous extracts of Pyrola decorate leaves were prepared by solvent sequential process, and then isolated and purified to obtain phytochemicals. Cell viability was measured by MTT assay. PC12 cells were pretreated for 24 h with different extractions of P. decorate leaves at concentrations of 0.1, 0.5, 1, 5 and 10 mg/mL, then H2O2 of 0.4 mM was added in all samples for an additional 2 h. The antioxidant capacities of betulin, ursolic acid and monotropein were determined in PC12 cells against H2O2 induced cytotoxicity in vitro as well. RESULTS: Nine compounds (1-9) were isolated and structurally determined by spectroscopic methods, especially 2D NMR analyses. Ethanol extract treated groups showed inhibitory activity with IC50 value of 10.83 mg/mL. Betulin, ursolic acid and monotropein were isolated from P. decorate, and demonstrated with IC50 values of 6.88, 6.15 and 6.13 µg/mL, respectively. DISCUSSION AND CONCLUSIONS: In conclusion, Pyrola decorate is a potential antioxidative natural plant and worth testing for further pharmacological investigation in the treatment of oxidative stress related neurological disease.

Quantitative study of cellular heterogeneity in doxorubicin uptake and its pharmacological effect on cancer cells.

Cellular heterogeneity in doxorubicin (DOX) uptake and its relationship with pharmacological effect on cancer cells were quantitatively investigated for the first time. An in vitro experimental model was established by treating human leukemia K562 and breast cancer MCF-7 cells with different schedules of DOX with or without surface P-glycoprotein (P-gp) inhibitor verapamil (VER). The cellular heterogeneity in DOX uptake was quantitatively examined by single-cell analysis using capillary electrophoresis coupled with laser-induced fluorescence detection. The corresponding cytotoxic effect was tested by cellular morphology, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium and flow cytometry assays. The expression of cellular membrane surface P-gp was determined by flow cytometry. Results showed that the cellular heterogeneity exists in DOX uptake. The single-high DOX schedule leads to lower uptake heterogeneity and higher mean drug uptake. The cellular heterogeneity in DOX uptake was found to be negatively correlated with drug cytotoxicity and surface P-gp expression, with r = -0.7680 to ~ -0.9587. VER reduces the cellular variation in DOX uptake, suggesting that surface P-gp may be one of the causes of the cellular heterogeneity in DOX uptake. This research demonstrates the importance of quantitative study of cellular heterogeneity in drug uptake and its potential application in drug schedule design, response prediction and therapy modulation.

A Review of the research methods and progress of biocompatibility evaluation of root canal sealers.

The function of root canal sealer was to achieve an appropriate three-dimensional filling effect by filling the root canal and some irregular lumen, thereby inhibiting the residual bacteria. There were many types of sealers, but research to find the most suitable ones was still ongoing. In recent years, researchers had continuously improved the performance of sealers by developing new sealers or adding active ingredients to the sealers. However, most sealers exhibit varying degrees of cytotoxicity and tissue responses, which affect clinical therapy efficacy. This review describes different technical approaches, and recent research progress in the biocompatibility evaluation of root canal sealers and provides brief insights into this field by summarising the performance studies of different root canal sealers.

Two new constituents from the endophyte of Alternaria alternata and its anti-neuroinflammatory activity guided by molecular docking.

Two new compounds, 3-hydroxy-1-(3-hydroxy-5-methoxyphenyl)-2-methyl propan-1-one (1) and 1,2,6-trihydroxy-8-methoxy-2,3,3a,9b-tetrahydrocyclopenta[c] isochromen-5(1H)-one (2), along with nine known compounds 3-11, involving pyranones, phenylpropenoids and alkaloids, were obtained from Alternaria alternata, an endophyte isolated from Hypericum perforatum L. The structures were elucidated by extensive spectroscopic analyses, including 1D NMR, 2D NMR, HRESIMS, IR, UV spectroscopy. The absolute configuration was established via spectroscopy techniques and X-ray crystallisation method. Furthermore, guided by molecular docking, compounds 1 and 3 exhibited promising anti-neuroinflammatory activity in LPS-induced BV-2 microglial cells, with IC50 values of 0.9 ± 0.3 µM and 3.0 ± 0.4 µM respectively. Moreover, they effectively attenuated the LPS-induced elevation of NO, TNF-α, IL-6, and IL-1ß production in BV-2 microglial cells. These findings diversify the metabolite of A. alternata and highlight their potential as leading compounds against neuroinflammatory-related diseases.

[In vitro study on cytotoxicity, osteogenic potential and antibacterial activity of silicate root canal sealers].

PURPOSE: To evaluate the in vitro biocompatibility and antibacterial activity of a new type of strontium silicate-based C-Root SP root canal sealer, and to provide a reference for clinical selection of sealers. METHODS: C-Root SP, iRoot SP and AH Plus extracts were prepared, L929 cells and MC3T3-E1 cells were cultured in vitro, and the cytotoxicity and osteogenic potential of the three sealers were compared. Fresh sealers were mixed with Enterococcus faecalis solution and the antibacterial activity of the sealer was determined by direct contact text (DCT). SPSS 25.0 software package was used for statistical analysis. RESULTS: At 24, 48, and 72 h, the cytotoxicity of the sealers in each group were significantly different (P＜0.01). Compared with AH Plus, the cytotoxicity of C-Root SP was lower (P＜0.01). C-Root SP was superior to AH Plus in promoting the activity of alkaline phosphatase(ALP) (P＜0.01). iRoot SP was the strongest in promoting the formation of mineralized nodules, followed by C-Root SP, and the weakest was AH Plus(P＜0.01). C-Root SP inhibited the growth of Enterococcus faecalis, and its antibacterial rate was significantly higher than AH Plus(P＜0.01). CONCLUSIONS: The strontium silicate root canal sealer C-Root SP has low cytotoxicity, certain osteogenic potential and antibacterial activity against Enterococcus faecalis, so it can be used for root canal filling.

Corilagin enhances the anti-tumor activity of 5-FU by downregulating the expression of GRP 78.

Colorectal cancer is one of the most common malignancies worldwide. Although initially effective, patients who receive chemotherapy ultimately experience various complications and develop chemo-resistance, leading to cancer recurrence. Therefore, we aimed to find a drug with good efficacy and low toxicity that could enhance the treatment with 5-Fluorouracil (a commonly used clinical drug) and reduce its dosing. Corilagin, an anti-tumor natural product, has received widespread attention. Glucose regulated protein 78 (GRP78) is overexpressed in colorectal cancer cells and plays a key role in the proliferation, migration and drug resistance of cancer cells. Importantly, GRP78 can affect the apoptosis induced by 5-fluorouracil in CRC cells. In the present study, we determined the synergistic anti-tumor activity of the combination treatment by cell proliferation assay, apoptosis assay, fluorescent staining, cell cycle analysis, WB and PCR assays. This synergistic effect was associated with S-phase blockade, intracellular reactive oxygen species production and downregulation of GRP78. Taken together, our results indicate that Corilagin acts as a potentiator of 5-fluorouracil and may have therapeutic potential for patients with CRC.

Secondary metabolites of Alternaria: A comprehensive review of chemical diversity and pharmacological properties.

Fungi are considered to be one of the wealthiest sources of bio-metabolites that can be employed for yielding novel biomedical agents. Alternaria, including parasitic, saprophytic, and endophytic species, is a kind of dark fungi that can produce a broad array of secondary metabolites (SMs) widely distributed in many ecosystems. These are categorized into polyketides, nitrogen-containing compounds, quinones, terpenes, and others based on the unique structural features of the metabolites. New natural products derived from Alternaria exhibit excellent bioactivities characterized by antibacterial, antitumor, antioxidative, phytotoxic, and enzyme inhibitory properties. Thus, the bio-metabolites of Alternaria species are significantly meaningful for pharmaceutical, industrial, biotechnological, and medicinal applications. To update the catalog of secondary metabolites synthesized by Alternaria fungi, 216 newly described metabolites isolated from Alternaria fungi were summarized with their diverse chemical structures, pharmacological activity, and possible biosynthetic pathway. In addition, possible insights, avenues, and challenges for future research and development of Alternaria are discussed.

Prevalence and correlates of cigarette smoking among Dulong adults in China: A cross-sectional survey in 2020.

Background: The Dulong people are one of the minorities in China with the lowest population. In recent years, the lifestyle of the Dulong people has also changed drastically due to income growth and urbanization. This study aims to identify cigarette smoking prevalence and potential risk factors among Dulong adults in China. Methods: This study was conducted among 1,018 adults based on the Dulong Health Status Investigation and Evaluation (DHSIE) in Gongshan Dulong and Nu Autonomous County of Yunnan province, Southwest China. A cross-sectional design and face-to-face questionnaire were used to collect cigarette smoking habits and demographic information. Data were weighted by post-stratification weights according to the age and gender composition of Dulong resident. We also analyzed univariate and multivariate unconditional logistic regression to explore current smoking correlates. Results: The weighted prevalence of ever-smoking, currently smoking, and formerly smoking among Dulong adults is 31.3, 27.7, and 3.6%, respectively. The prevalence of ever-smoking and currently smoking among male participants (57.0 and 50.6%) is much higher than that of female participants (4.0 and 3.4%). Nearly 60% of ever-smokers and current smokers smoked more than 20 cigarettes per day, which are higher than former smokers (35.2%). Among current smokers, 33.1% relapsed, and 28.3% intend to quit smoking. By adjusting for potential confounding variables, multiple logistic regression analysis indicated that male participants (OR = 48.982, 95% CI: 25.026-95.869) and current drinkers (OR = 4.450, 95% CI: 2.556-7.746) are more likely to be current smokers. On the contrary, current smokers are also more likely to be exposed to secondhand smoke (OR = 4.269, 95% CI: 2.330-7.820) and have a higher risk of chronic respiratory disease (OR = 4.955, 95% CI: 1.669-14.706). Conclusion: Cigarette smoking is highly prevalent among the Dulong people in Southwest China. An appropriate and effective tobacco control strategy is an urgent need for this population.

Two new dipimprinine alkaloids from soil-derived Streptomyces sp. 44414B.

Two new dipimprinine alkaloids dipimprinine E (1) and dipimprinine F (2) were isolated from Streptomyces sp. 44414B. The structure was elucidated by extensive spectroscopic analysis, including ESI-MS, HR-MS, and 1D and 2D NMR experiments. Dipimprinines F (2) showed cytotoxic activities against three tumor cell lines, including A-875, Hep G2, and H-460, with IC50 values of 26.4, 0.5, and 9.0 µg ml-1, respectively.

Origins, Structures, and Bioactivities of Secondary Metabolites from Marine-derived Penicillium Fungi.

In recent years, marine-derived Penicillium fungi have received remarkable interest as a valuable source of novel natural products encompassing diverse chemical structures and bioactive properties. Mangroves, sediments, algae, and sponges are the four main sources of marine-derived Penicillium fungi. As of 2014, more than 390 novel natural products have been isolated from the marine- derived Penicillium fungi, mainly including polyketides, alkaloids, terpenoids, and macrolides. Biological investigations have shown that these compounds possess antimicrobial, anti-inflammatory, cytotoxic, and other activities with potential applications in new drug development. To provide an updated catalog of this field, our mini-review summarized the origins, structures, and bioactivities of 188 secondary metabolites from marine-derived Penicillium fungi based on bioactivities classification published from 2015 to 2020.