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1.
Nguyen Huy Hung Pham Minh Quan Do Ngoc Dai Prabodh Satyal Le Thi Huong Le Duc Giang Le Thanh Hung William N. Setzer 《化学与生物多样性》2023,20(3):e202200210
There is an ongoing interest to identify alternative pesticidal agents to avoid the chronic problems associated with synthetic pesticides. Essential oils have shown promise as botanical pest control agents. In the present study, the essential oils of four members of the Lamiaceae (Callicarpa candicans, C. erioclona, C. macrophylla, and Karomia fragrans; Vietnamese names: Nàng nàng, Tu châu lông mem, Tu châu lá to and Cà diện, respectively), obtained from wild populations in Vietnam, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils were formulated into microemulsions and the essential oils and their microemulsions were screened for mosquito larvicidal activity against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and for molluscicidal activity against Pomacea canaliculata. Atractylone and (E)-caryophyllene dominated the volatiles of C. candicans (CCEO) and C. erioclona (CEEO), while the major component in C. macrophylla (CMEO) and K. fragrans (KFEO) was (E)-caryophyllene. The essential oils and microemulsions of both C. candicans and C. erioclona exhibited excellent larvicidal activity against all three mosquito species (Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus) with LC50 values <10 μg/mL. Additionally, the larvicidal activity of the microemulsions were significantly improved compared with their free essential oils, especially for C. candicans and C. erioclona. All four essential oils and their microemulsions showed excellent molluscicidal activity with LC50 <10 μg/mL. In most cases, the essential oils and microemulsions showed greater pesticidal activity against target organisms than the non-target freshwater fish, Oreochromis niloticus. The in silico studies on physicochemical and ADMET properties of the major components in the studied essential oils were also investigated and most of the compounds possessed a favorable ADMET profile. Computational modeling studies of the studied compounds demonstrated a favorable binding interaction with the mosquito odorant-binding protein target and support atractylone, β-selinene, and caryophyllene oxide as potential inhibitors. Based on the observed pesticidal activities of the essential oils and their microemulsions, the Callicarpa species and K. fragrans should be considered for potential cultivation and further exploration as botanical pesticidal agents. 相似文献
2.
Samil Jung Davaajargal Myagmarjav Taeyeon Jo Soonduk Lee Songyi Han Nguyen Thi Ngoc Quynh Nguyen Hai Anh Son Hai Vu Yeongseon Choi Myeong-Sok Lee 《International journal of biological sciences》2022,18(9):3859
Chemotherapy has been widely used as a clinical treatment for cancer over the years. However, its effectiveness is limited because of resistance of cancer cells to programmed cell death (PCD) after treatment with anticancer drugs. To elucidate the resistance mechanism, we initially focused on cancer cell-specific mitophagy, an autophagic degradation of damaged mitochondria. This is because mitophagy has been reported to provide cancer cells with high resistance to anticancer drugs. Our data showed that TRIP-Br1 oncoprotein level was greatly increased in the mitochondria of breast cancer cells after treatment with various anticancer drugs including staurosporine (STS), the main focus of this study. STS treatment increased cellular ROS generation in cancer cells, which triggered mitochondrial translocation of TRIP-Br1 from the cytosol via dephosphorylation of TRIP-Br1 by protein phosphatase 2A (PP2A). Up-regulated mitochondrial TRIP-Br1 suppressed cellular ROS levels. In addition, TRIP-Br1 rapidly removed STS-mediated damaged mitochondria by activating mitophagy. It eventually suppressed STS-mediated PCD via degradation of VDACI, TOMM20, and TIMM23 mitochondrial membrane proteins. TRIP-Br1 enhanced mitophagy by increasing expression levels of two crucial lysosomal proteases, cathepsins B and D. In conclusion, TRIP-Br1 can suppress the sensitivity of breast cancer cells to anticancer drugs by activating autophagy/mitophagy, eventually promoting cancer cell survival. 相似文献
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Coronavirus disease-2019 (COVID-19) has affected more than 200 countries worldwide. This disease has hugely affected healthcare systems as well as the economy to an extent never seen before. To date, COVID-19 infection has led to about 165000 deaths in 150 countries. At present, there is no specific drug or efficient treatment for this disease. In this analysis based on evidential relationships of the biological characteristics of MSCs, especially umbilical cord (UC)-derived MSCs as well as the first clinical trial using MSCs for COVID-19 treatment, we discuss the use of UC-MSCs to improve the symptoms of COVID-19 in patients. 相似文献
5.
Density functional theory (DFT) calculations performed at the PBE/DZP level using the DFT-D2 method were utilized to investigate the adsorption of phenol on pristine activated carbon (AC) and on activated carbon functionalized with OH, CHO, or COOH groups. Over the pristine AC, the phenol molecule undergoes weak physical adsorption due to van der Waals interactions between the aromatic part of the phenol and the basal planes of the AC. Among the three functional groups used to functionalize the AC, the carboxylic group was found to interact most strongly with the hydroxyl group of phenol. These results suggest that functionalized AC-COOH has great potential for use in environmental applications as an adsorbent of phenol molecules in aqueous phases. 相似文献
6.
The Shigella flexneri outer membrane (OM) protease IcsP (SopA) is a member of the enterobacterial Omptin family of proteases which cleaves the polarly localised OM protein IcsA that is essential for Shigella virulence. Unlike IcsA however, the specific localisation of IcsP on the cell surface is unknown. To determine the distribution of IcsP, a haemagglutinin (HA) epitope was inserted into the non-essential IcsP OM loop 5 using Splicing by Overlap Extension (SOE) PCR, and IcsPHA was characterised. Quantum Dot (QD) immunofluorescence (IF) surface labelling of IcsPHA was then undertaken. Quantitative fluorescence analysis of S. flexneri 2a 2457T treated with and without tunicaymcin to deplete lipopolysaccharide (LPS) O antigen (Oag) showed that IcsPHA was asymmetrically distributed on the surface of septating and non-septating cells, and that this distribution was masked by LPS Oag in untreated cells. Double QD IF labelling of IcsPHA and IcsA showed that IcsPHA preferentially localised to the new pole of non-septating cells and to the septum of septating cells. The localisation of IcsPHA in a rough LPS S. flexneri 2457T strain (with no Oag) was also investigated and a similar distribution of IcsPHA was observed. Complementation of the rough LPS strain with rmlD resulted in restored LPS Oag chain expression and loss of IcsPHA detection, providing further support for LPS Oag masking of surface proteins. Our data presents for the first time the distribution for the Omptin OM protease IcsP, relative to IcsA, and the effect of LPS Oag masking on its detection. 相似文献
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8.
Justin M. Greene Jennifer J. Lhost Paul J. Hines Matthew Scarlotta Max Harris Benjamin J. Burwitz Melisa L. Budde Dawn M. Dudley Ngoc Pham Brian Cain Caitlin E. Mac Nair Madelyn K. Weiker Shelby L. O'Connor Thomas C. Friedrich David H. O'Connor 《Journal of virology》2013,87(13):7382-7392
The live attenuated simian immunodeficiency virus (SIV) SIVmac239Δnef is the most effective SIV/human immunodeficiency virus (HIV) vaccine in preclinical testing. An understanding of the mechanisms responsible for protection may provide important insights for the development of HIV vaccines. Leveraging the uniquely restricted genetic diversity of Mauritian cynomolgus macaques, we performed adoptive transfers between major histocompatibility complex (MHC)-matched animals to assess the role of cellular immunity in SIVmac239Δnef protection. We vaccinated and mock vaccinated donor macaques and then harvested between 1.25 × 109 and 3.0 × 109 mononuclear cells from multiple tissues for transfer into 12 naive recipients, followed by challenge with pathogenic SIVmac239. Fluorescently labeled donor cells were detectable for at least 7 days posttransfer and trafficked to multiple tissues, including lung, lymph nodes, and other mucosal tissues. There was no difference between recipient macaques'' peak or postpeak plasma viral loads. A very modest difference in viral loads during the chronic phase between vaccinated animal cell recipients and mock-vaccinated animal cell recipients did not reach significance (P = 0.12). Interestingly, the SIVmac239 challenge virus accumulated escape mutations more rapidly in animals that received cells from vaccinated donors. These results may suggest that adoptive transfers influenced the course of infection despite the lack of significant differences in the viral loads among animals that received cells from vaccinated and mock-vaccinated donor animals. 相似文献
9.
Nguyen Hoang Loc Le My Tieu Ngoc Tran Thuy Lan Le Quoc Viet Le Duc Thao Hoang Tan Quang Dinh Thi Bich Lan Phung Thang Long 《Indian journal of microbiology》2013,53(4):488-491
We cloned two genes coding F107-C and K88-1NT fimbrial subunits from strains E. coli C and 1NT isolated from Thua Thien Hue province, Vietnam. The mature peptide of faeG gene from strain E. coli 1NT (called faeG-1NT) is 100 % similarity with faeG gene, while the CDS of fedA gene from strain C (called fedA-C) has a similarity of 97 % with the fedA gene. Expression of the faeG-1NT and fedA-C genes in E. coli BL21 Star™ (DE3) produced proteins of ~31 and 22 kDa, respectively. The effect of IPTG concentration on the K88-1NT and F107-C fimbriae production was investigated. The results showed that 0.5 mM IPTG is suitable for higher expression of K88-1NT subunit, while 0.75 mM IPTG strongly stimulated expression of F107-C subunit. The optimal induction time for expression was also examined. Generally, highest expression of K88-1NT subunit occurred after 6 h of induction, while that of F107-C subunit is after 14 h. 相似文献
10.
Nguyen Phuong Thao Le Duc Dat Ninh Thi Ngoc Vu Anh Tu Tran Thi Hong Hanh Phan Thi Thanh Huong Nguyen Xuan Nhiem Bui Huu Tai Nguyen Xuan Cuong Nguyen Hoai Nam Pham Van Cuong Seo Young Yang Sohyun Kim Doobyeong Chae Young-Sang Koh Phan Van Kiem Chau Van Minh Young Ho Kim 《Bioorganic & medicinal chemistry letters》2013,23(6):1823-1827
Three new pyrrole oligoglycosides, astebatheriosides A–C (1–3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8 μM, respectively. 相似文献