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1.
Virology ; 600: 110219, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39278102

RESUMO

In response to the problems associated with drug resistance resulting from the use of antibiotics, phages have become desirable options for the treatment of Vibrio alginolyticus disease in aquaculture. In this study, we isolated a novel double-stranded DNA (dsDNA) phage named vB_ValC_WD615 infecting V. alginolyticus; this phage belongs to the family Podoviridae and has a short noncontractile tail (13 ± 1.5 nm) and an icosahedral head (60.2 ± 2 nm); its genome is 50,522 bp and encodes 69 open reading frames (ORFs) and no lysogenic genes were annotated in the genome. Physiological results indicate that vB_ValC_WD615 infects V. alginolyticus SC1 with a burst size of 335 PFU/cell and can maintain stable infectivity within temperature and pH conditions ranging from 4 to 45 °C and 3 to 11, respectively. The results suggest that the vB_ValC_WD615 isolated from coastal waters could be a potential candidate for phage therapy targeting V. alginolyticus.

2.
Evol Bioinform Online ; 20: 11769343241261814, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883803

RESUMO

Background: Pseudogenes are sequences that have lost the ability to transcribe RNA molecules or encode truncated but possibly functional proteins. While they were once considered to be meaningless remnants of evolution, recent researches have shown that pseudogenes play important roles in various biological processes. However, the studies of pseudogenes in the silkworm, an important model organism, are limited and have focused on single or only a few specific genes. Objective: To fill these gaps, we present a systematic genome-wide studies of pseudogenes in the silkworm. Methods: We identified the pseudogenes in the silkworm using the silkworm genome assemblies, transcriptome, protein sequences from silkworm and its related species. Then we used transcriptome datasets from 832 RNA-seq analyses to construct spatio-temporal expression profiles for these pseudogenes. Additionally, we identified tissue-specifically expressed and differentially expressed pseudogenes to further understand their characteristics. Finally, the functional roles of pseudogenes as lncRNAs were systematically analyzed. Results: We identified a total of 4410 pseudogenes, which were grouped into 4 groups, including duplications (DUPs), unitary pseudogenes (Unitary), processed pseudogenes (retropseudogenes, RETs), and fragments (FRAGs). The most of pseudogenes in the domestic silkworm were generated before the divergence of wild and domestic silkworm, however, the domestication may also involve in the accumulation of pseudogenes. These pseudogenes were clearly divided into 2 cluster, a highly expressed and a lowly expressed, and the posterior silk gland was the tissue with the most tissue-specific pseudogenes (199), implying these pseudogenes may be involved in the development and function of silkgland. We identified 3299 lncRNAs in these pseudogenes, and the target genes of these lncRNAs in silkworm pseudogenes were enriched in the egg formation and olfactory function. Conclusions: This study replenishes the genome annotations for silkworm, provide valuable insights into the biological roles of pseudogenes. It will also contribute to our understanding of the complex gene regulatory networks in the silkworm and will potentially have implications for other organisms as well.

3.
Clin Toxicol (Phila) ; 62(4): 229-236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38668745

RESUMO

INTRODUCTION: Many studies have focused on snakebites in adults, but very few have described snakebites in children. METHODS: We reviewed the clinical characteristics and outcomes of children with venomous snakebites aged less than 15 years who presented to a regional medical centre in South China from January 2013 to December 2022. RESULTS: A total of 69 envenomed patients were analyzed in our study; 42 (60.9 per cent) patients were male, and 59 (85.5 per cent) reported lower limb bites. Most bites (89.8 per cent) occurred between April and October. Twenty-seven patients received first aid management, and 47 required admission to the general ward. Antivenom was administered to 58 patients, glucocorticoids to 43 patients, antibiotics to 48 patients, and tetanus antitoxin to 40 patients. No fatalities were reported. The most common snake identified was Trimeresurus albolabris. Four were classified as dry bites, 15 as mild, 43 as moderate, and seven as severe. The most common local signs were pain and swelling, while the most common systemic effects were haematological complications. Patients with high severity scores had significantly higher lactate dehydrogenase activities, creatine kinase isoenzyme activities, aspartate aminotransferase activities, D-dimer concentrations, prothrombin times and lower fibrinogen concentrations. In a receiver operating characteristic curve analysis of the values with the highest Youden index, the following cut-offs proved significant: lactate dehydrogenase activity > 248.1 U/L, creatine kinase isoenzyme activities > 17.5 U/L, fibrinogen concentration < 1,455 mg/L, D-dimer concentration > 437.0 µg/L, aspartate aminotransferase activity > 26.1 U/L, and prothrombin time > 15.2 seconds. DISCUSSION: This study provides insight into the epidemiology, clinical profile, and management of snakebites in children. Data from the present study were compared with those from our previous adult study. Limitations include that 50.7 per cent of our snakebites were attributed to Trimeresurus albolabris. Therefore, the results of our study may not be generalizable to all snakebites. CONCLUSION: The clinical symptoms were more severe in children than in adults in our previous study. Even though there were no fatalities, close monitoring should be performed to detect haematological and other potentially fatal complications promptly.


Assuntos
Antivenenos , Mordeduras de Serpentes , Mordeduras de Serpentes/epidemiologia , Mordeduras de Serpentes/terapia , Mordeduras de Serpentes/tratamento farmacológico , Humanos , Masculino , Criança , Feminino , China/epidemiologia , Pré-Escolar , Adolescente , Antivenenos/uso terapêutico , Estudos Retrospectivos , Lactente , Animais , Índice de Gravidade de Doença
4.
Insects ; 15(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38392522

RESUMO

Transmembrane emp24 domain (TMED) proteins have been extensively studied in mammalian embryonic development, immune regulation, and signal transduction. However, their role in insects, apart from Drosophila melanogaster, remains largely unexplored. Our previous study demonstrated the abundant expression of BmTMED6 across all stages and tissues of the silkworm. In this study, we investigate the function of BmTMED6 in reproduction. We observe significant differences in the expression of BmTMED6 between male and female silkworms, particularly in the head and fatboby, during the larval stage. Furthermore, qRT-PCR and WB analysis reveal substantial variation in BmTMED6 levels in the ovaries during pupal development, suggesting a potential association with silkworm female reproduction. We find that reducing TMED6 expression significantly decreases the number of eggs laid by female moths, leading to an accumulation of unlaid eggs in the abdomen. Moreover, downregulation of BmTMED6 leads to a decrease in the expression of BmDop2R1 and BmDop2R2, while overexpression of BmTMED6 in vitro has the opposite effect. These indicate that BmTMED6 plays a role in oviposition in female moths, potentially through the dopamine signaling pathway. This study provides a new regulatory mechanism for female reproduction in insects.

5.
ISA Trans ; 138: 262-280, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36906442

RESUMO

In order to improve the multiple-missile cooperative attack capability and penetration capability, this paper investigates two three-dimensional impact-angle-constrained cooperative guidance strategies against maneuvering target for controllable thrust missiles. First, a three-dimensional nonlinear guidance model is established that does not assume small missile lead angles in the guidance process. Second, in the line-of-sight (LOS) direction of the cluster cooperative guidance strategy, the proposed guidance algorithm transforms the simultaneous attack problem into a second-order multiagent consensus problem, which effectively solves the practical problem of low guidance precision provoked by the time-to-go estimation. Then, by combining second-order sliding mode control (SMC) and nonsingular terminal SMC theory, the guidance algorithms in the normal and lateral directions to the LOS are designed, respectively, so that the multi-missile can accurately attack a maneuvering target while satisfying the impact angle constraints. Finally, by utilizing the second-order multiagent consensus tracking control in the leader-following cooperative guidance strategy, a novel leader-following time consistency algorithm is investigated to ensure that the leader and followers can attack the maneuvering target simultaneously. Moreover, the stability of the investigated guidance algorithms is proved mathematically. The effectiveness and superiority of the proposed cooperative guidance strategies are verified by numerical simulations.

6.
J Cardiovasc Pharmacol ; 81(2): 150-164, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607630

RESUMO

ABSTRACT: Uric acid (UA) accumulation triggers endothelial dysfunction, oxidative stress, and inflammation. Histone deacetylase (HDAC) plays a vital role in regulating the pathological processes of various diseases. However, the influence of HDAC inhibitor on UA-induced vascular endothelial cell injury (VECI) remains undefined. Hence, this study aimed to investigate the effect of HDACs inhibition on UA-induced vascular endothelial cell dysfunction and its detailed mechanism. UA was used to induce human umbilical vein endothelial cell (HUVEC) injury. Meanwhile, potassium oxonate-induced and hypoxanthine-induced hyperuricemia mouse models were also constructed. A broad-spectrum HDAC inhibitor trichostatin A (TSA) or selective HDAC6 inhibitor TubastatinA (TubA) was given to HUVECs or mice to determine whether HDACs can affect UA-induced VECI. The results showed pretreatment of HUVECs with TSA or HDAC6 knockdown-attenuated UA-induced VECI and increased FGF21 expression and phosphorylation of AKT, eNOS, and FoxO3a. These effects could be reversed by FGF21 knockdown. In vivo, both TSA and TubA reduced inflammation and tissue injury while increased FGF21 expression and phosphorylation of AKT, eNOS, and FoxO3a in the aortic and renal tissues of hyperuricemia mice. Therefore, HDACs, especially HDAC6 inhibitor, alleviated UA-induced VECI through upregulating FGF21 expression and then activating the PI3K/AKT pathway. This suggests that HDAC6 may serve as a novel therapeutic target for treating UA-induced endothelial dysfunction.


Assuntos
Inibidores de Histona Desacetilases , Hiperuricemia , Animais , Humanos , Camundongos , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/farmacologia , Inibidores de Histona Desacetilases/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Células Endoteliais da Veia Umbilical Humana , Inflamação/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Ácido Úrico
7.
PeerJ ; 11: e14682, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655040

RESUMO

The silkworm (Bombyx mori) is not only an excellent model species, but also an important agricultural economic insect. Taking it as the research object, its advantages of low maintenance cost and no biohazard risks are considered. Small open reading frames (smORFs) are an important class of genomic elements that can produce bioactive peptides. However, the smORFs in silkworm had been poorly identified and studied. To further study the smORFs in silkworm, systematic genome-wide identification is essential. Here, we identified and analyzed smORFs in the silkworm using comprehensive methods. Our results showed that at least 738 highly reliable smORFs were found in B. mori and that 34,401 possible smORFs were partially supported. We also identified some differentially expressed and tissue-specific-expressed smORFs, which may be closely related to the characteristics and functions of the tissues. This article provides a basis for subsequent research on smORFs in silkworm, and also hopes to provide a reference point for future research methods for smORFs in other species.


Assuntos
Bombyx , Animais , Bombyx/genética , Fases de Leitura Aberta/genética , Filogenia
8.
Int J Cardiol ; 371: 332-344, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181956

RESUMO

BACKGROUND: Iroquois homeobox 2 (IRX2) is a member of the Iroquois family whose upregulation has been potentially correlated to cardiac hypertrophy. This work studied the function of IRX2 and its related molecules in hypertrophic cardiomyopathy (HCM). METHODS: A GEO dataset GSE32453 was analyzed to identify aberrantly expressed genes in HCM. Altered expression of IRX2 was induced in mice by lentivirus injection, followed by angiotensin II (Ang II) treatment to induce HCM. The function of IRX2 knockdown in ventricular dysfunction, heart volume and pathological changes in mice, and in surface area, oxidative stress and apoptosis of isolated cardiomyocytes were examined. Binding relationship between jumonji domain-containing protein 2A (JMJD2A) and IRX2 was predicted by online tools and validated. The interaction between JMJD2A and IRX2 in HCM development was examined by joint interventions. RESULTS: IRX2 was highly expressed in heart tissues with HCM. IRX2 knockdown prevented mice from Ang II-induced ventricular dysfunction, cardiac hypertrophy, inflammation and fibrosis in mouse heart, and it decreased the levels of cardiac hypertrophy-related markers, oxidative stress response, and apoptosis of Ang II-treated cardiomyocytes. JMJD2A catalyzed demethylation of H3K9me3 near the IRX2 promoter to activate its transcription. JMJD2A knockdown similarly exerted protective functions against cardiac hypertrophy in vivo and in vitro, but the protection was blocked upon further IRX2 upregulation. IRX2 was found to increase the Wnt/ß-catenin signaling activation. CONCLUSION: This work reports that JMJD2A activates IRX2 transcription and the Wnt/ß-catenin signaling to induce cardiac hypertrophy and dysfunction in HCM.


Assuntos
Cardiomiopatia Hipertrófica , Proteínas de Homeodomínio , Histona Desmetilases com o Domínio Jumonji , Disfunção Ventricular , Animais , Camundongos , Angiotensina II/toxicidade , Angiotensina II/metabolismo , beta Catenina/metabolismo , Cardiomegalia/metabolismo , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Disfunção Ventricular/genética , Disfunção Ventricular/patologia , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/genética
9.
Molecules ; 27(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889201

RESUMO

In this study, we report on the synthesis of new organoselenium derivatives, including nonsteroidal anti-inflammatory drugs (NSAIDs) scaffolds and Se functionalities (isoselenocyanate and selenourea), which were evaluated against four types of cancer cell line: SW480 (human colon adenocarcinoma cells), HeLa (human cervical cancer cells), A549 (human lung carcinoma cells), MCF-7 (human breast adenocarcinoma cells). Among these compounds, most of the investigated compounds reduced the viability of different cancer cell lines. The most promising compound 6b showed IC50 values under 10 µM against the four cancer cell lines, particularly to HeLa and MCF-7, with IC50 values of 2.3 and 2.5 µM, respectively. Furthermore, two compounds, 6b and 6f, were selected to investigate their ability to induce apoptosis in MCF-7 cells via modulation of the expression of anti-apoptotic Bcl-2 protein, pro-inflammatory cytokines (IL-2) and proapoptotic caspase-3 protein. The redox properties of the NSAIDs-Se derivatives were conducted by 2, 2-didiphenyl-1-picrylhydrazyl (DPPH), bleomycin-dependent DNA damage and glutathione peroxidase (GPx)-like assays. Finally, a molecular docking study revealed that an interaction with the active site of thioredoxin reductase 1 (TrxR1) predicted the antiproliferative activity of the synthesized candidates. Overall, these results could serve as a promising launch point for further designs of NSAIDs-Se derivatives as potential antiproliferative agents.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Organosselênicos , Relação Estrutura-Atividade , Ureia/análogos & derivados
10.
Cytometry A ; 101(3): 254-263, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34448526

RESUMO

The potential of flow cytometry for the study of changes in prodigiosin on the cell surface of Serratia marcescens is of academic and practical interest. This is because S. marcescens can produce prodigiosin, a secondary metabolite, with potential use as a cancer-cell inhibitor. In this study, three groups of bacterial cultures with different carbon sources were compared, and the effect of the addition of cAMP to the sucrose-based culture was studied. Both cellular morphology and DNA content were detected by flow cytometry, rendering a broad description of the bacterial behavior. It is the first use of flow cytometry to investigate the dynamics of prodigiosin on the surface of S. marcescens during growth in different media. The fluorescence intensity is related to the DNA content, the forward-scattered light is related to cell volume, and the side-scattered light is related to the surface morphology, especially the surface prodigiosin. These may contribute to the potential development of a bacterial metabolic monitoring strategy using both DNA content analysis and bacterial morphology based on flow cytometry technique.


Assuntos
Prodigiosina , Serratia marcescens , Meios de Cultura/metabolismo , DNA/metabolismo , Citometria de Fluxo , Prodigiosina/metabolismo , Prodigiosina/farmacologia , Serratia marcescens/genética , Serratia marcescens/metabolismo
11.
Nat Commun ; 12(1): 2693, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976158

RESUMO

Notch signaling represents a key mechanism mediating cancer metastasis and stemness. To understand how Notch signaling is overactivated to couple tumor metastasis and self-renewal in NSCLC cells, we performed the current study and showed that RFC4, a DNA replication factor amplified in more than 40% of NSCLC tissues, directly binds to the Notch1 intracellular domain (NICD1) to competitively abrogate CDK8/FBXW7-mediated degradation of NICD1. Moreover, RFC4 is a functional transcriptional target gene of Notch1 signaling, forming a positive feedback loop between high RFC4 and NICD1 levels and sustained overactivation of Notch signaling, which not only leads to NSCLC tumorigenicity and metastasis but also confers NSCLC cell resistance to treatment with the clinically tested drug DAPT against NICD1 synthesis. Furthermore, together with our study, analysis of two public datasets involving more than 1500 NSCLC patients showed that RFC4 gene amplification, and high RFC4 and NICD1 levels were tightly correlated with NSCLC metastasis, progression and poor patient prognosis. Therefore, our study characterizes the pivotal roles of the positive feedback loop between RFC4 and NICD1 in coupling NSCLC metastasis and stemness properties and suggests its therapeutic and diagnostic/prognostic potential for NSCLC therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Receptor Notch1/genética , Proteína de Replicação C/genética , Transdução de Sinais/genética , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/terapia , Linhagem Celular Tumoral , Retroalimentação Fisiológica , Feminino , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Metástase Neoplásica , Receptor Notch1/metabolismo , Proteína de Replicação C/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
12.
Oncogene ; 40(19): 3449-3459, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33859372

RESUMO

Long non-coding RNAs (lncRNAs) are emerging as a new class of regulators for a variety of biological processes and have been suggested to play pivotal roles in cancer development and progression. Our current study found that a lncRNA, designated enhancing IL-6/STAT3 signaling activation (LEISA, ENST00000603468), functioned as an oncogenic lncRNA in lung adenocarcinoma (LAD), a major form of non-small cell lung carcinoma, which is one of the most frequently diagnosed malignancies with high morbidity and mortality worldwide, and was involved in the regulation of STAT3 induced IL-6 transcription. Our data showed that LEISA was highly expressed in, and correlated with the clinical progression and prognosis of LAD. Ectopic expression of LEISA promoted the proliferation and suppressed apoptosis of LAD cells in vitro and in vivo. Mechanistically, we demonstrated that LEISA recruited STAT3 to bind the promoter of IL-6 and upregulated IL-6 expression. Taken together, our work identifies LEISA as a potential diagnostic biomarker and therapeutic target for LAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Interleucina-6/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Fator de Transcrição STAT3/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Progressão da Doença , Xenoenxertos , Humanos , Interleucina-6/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Regiões Promotoras Genéticas , Fator de Transcrição STAT3/metabolismo , Taxa de Sobrevida
13.
PeerJ ; 9: e10818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33604192

RESUMO

Wild (Bombyx mandarina) and domestic silkworms (B. mori) are good models for investigating insect domestication, as 5000 years of artificial breeding and selection have resulted in significant differences between B. mandarina and B. mori. In this study, we improved the genome assemblies to the chromosome level and updated the protein-coding gene annotations for B. mandarina. Based on this updated genome, we identified 68 cytochrome P450 genes in B. mandarina. The cytochrome P450 repository in B. mandarina is smaller than in B. mori. Certain currently unknown key genes, rather than gene number, are critical for insecticide resistance in B. mandarina, which shows greater resistance to insecticides than B. mori. Based on the physical maps of B. mandarina, we located 66 cytochrome P450s on 18 different chromosomes, and 27 of the cytochrome P450 genes were concentrated into seven clusters. KEGG enrichment analysis of the P450 genes revealed the involvement of cytochrome P450 genes in hormone biosynthesis. Analyses of the silk gland transcriptome identified candidate cytochrome P450 genes (CYP306A) involved in ecdysteroidogenesis and insecticide metabolism in B. mandarina.

14.
Int J Biol Macromol ; 164: 3771-3779, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32891645

RESUMO

DNA methylation is an important epigenetic modification and has been shown to be involved in the response to abiotic stress. However, there are few studies on DNA methylation in insect response to environmental signals. In this study, we conducted a comprehensive comparative analysis of DNA methylation profiles between two silkworm strains with significantly different resistance to heat and humidity by whole-genome bisulfite sequencing (WGBS). We identified, in total, 2934 differentially methylated regions (DMRs) between RT_48h (resistant strain with high-temperature/humidity treatment for 48 h) and ST_48h (sensitive strain with high-temperature/humidity treatment for 48 h) under cytosine context (CG), which corresponded to 1230 DMR-related genes (DMGs), and the DMRs were primarily located in the gene body (exon and intron) region. Gene ontology (GO) and KEGG analysis showed that these DMGs were most significantly enriched in binding, cellular metabolic process, and RNA transport pathways. Moreover, 10 DMGs have been revealed to be involved in the heat-humidity stress response in the silkworm. The results of this study indicated that DNA methylation plays crucial roles in silkworm response to environmental stressors and provides important clues to identify key resistance genes in silkworm under high-temperature/humidity stress response.


Assuntos
Bombyx/genética , Metilação de DNA/genética , Epigênese Genética/genética , Estresse Fisiológico/genética , Animais , Bombyx/fisiologia , Genoma de Inseto/genética , Resposta ao Choque Térmico/genética , Temperatura Alta/efeitos adversos , Umidade/efeitos adversos , Sulfitos/metabolismo , Sequenciamento Completo do Genoma
15.
Chem Eng Sci ; 223: 115727, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32362678

RESUMO

Baculovirus systems are used for various purposes, but the kinetics of the infection process is not fully understood yet. We investigated the dynamics of virion movement from a medium toward the interior of insect cells and established a mechanistic model that shows an excellent fit to experimental results. It also makes possible a description of the viral dynamics on the cell surface. A novel measurement method was used to distinguish between infected cells that carry virions on their surfaces, cells that carry virions in their interior, and those carrying virions both inside and on their surface. The maximum number of virions carried by a cell: 55 viruses/cell, and the time required for viral internalization, 0.8 h , are reported. This information is particularly useful for assessing the infection efficacy and the required number of virions needed to infect a given cell population. Although our model specifically concerns the infection process of Sf9 insect cells by baculovirus, it describes general features of viral infection. Some of the model features may eventually be applicable in the studies towards palliation of the COVID-19 outbreak.

16.
Chem Biodivers ; 17(5): e1900603, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32198823

RESUMO

In the present study, twenty-four selenocyanate and diselenide compounds were synthesized and characterized, and their anticancer activities against the human cancer cell lines Caco2, BGC-823, MCF-7 and PC-3 were determined. Interestingly, most of the new compounds were active in reducing the viability of different cancer cell lines. Two compounds exhibited higher promising activities than other derivatives. The most active compound showed the least IC50 values against the four cancer cell lines, particularly to PC-3 with IC50 values below 5 µm. Two compounds were selected to monitor the expression levels of Bcl-2, IL-2 and caspase-3 molecular biomarkers. Interestingly, the two compounds downregulated the Bcl-2 expression levels and upregulated the expression of IL-2 and caspase-3 in PC-3 cells compared to untreated cells. Moreover, most of the synthesized organoselenides exhibited good Gpx-like activities comparable to ebselen. These results appear that introduction of selenocyanate (-SeCN) or diselenides (-Se-Se-) moiety to some carboxy derivatives could serve as a promising launch point for the further design of this type of organic selenium anticancer agent.


Assuntos
Antineoplásicos/farmacologia , Cianatos/farmacologia , Compostos Organosselênicos/farmacologia , Compostos de Selênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Cianatos/síntese química , Cianatos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Compostos de Selênio/síntese química , Compostos de Selênio/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
PLoS One ; 12(5): e0177641, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542312

RESUMO

Thermotolerance is important particularly for poikilotherms such as insects. Understanding the mechanisms by which insects respond to high temperatures can provide insights into their adaptation to the environment. Therefore, in this study, we performed a transcriptome analysis of two silkworm strains with significantly different resistance to heat as well as humidity; the thermo-resistant strain 7532 and the thermos-sensitive strain Knobbed. We identified in total 4,944 differentially expressed genes (DEGs) using RNA-Seq. Among these, 4,390 were annotated and 554 were novel. Gene Ontology (GO) analysis of 747 DEGs identified between RT_48h (Resistant strain with high-temperature Treatment for 48 hours) and ST_48h (Sensitive strain with high-temperature Treatment for 48 hours) showed significant enrichment of 12 GO terms including metabolic process, extracellular region and serine-type peptidase activity. Moreover, we discovered 12 DEGs that may contribute to the heat-humidity stress response in the silkworm. Our data clearly showed that 48h post-exposure may be a critical time point for silkworm to respond to high temperature and humidity. These results provide insights into the genes and biological processes involved in high temperature and humidity tolerance in the silkworm, and advance our understanding of thermal tolerance in insects.


Assuntos
Bombyx/genética , Bombyx/fisiologia , Perfilação da Expressão Gênica , Temperatura Alta , Umidade , Estresse Fisiológico/genética , Termotolerância/genética , Animais , Ontologia Genética , Análise de Sequência de RNA , Especificidade da Espécie
18.
Bioresour Technol ; 147: 307-314, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24001560

RESUMO

Oil palm empty fruit bunch (OPEFB), contains abundant cellulose and hemicelluloses and can be used as a renewable resource for fuel and chemical production. This study, as the first attempt, aims to convert OPEFB derived sugars to polyhydroxybutyrate (PHB). OPEFB collected from a Malaysia palm oil refinery plant was chemically pretreated and enzymatically hydrolyzed by an in-house prepared cellulase cocktail. The PHB producer, Bacillus megaterium R11, was isolated in Singapore and could accumulate PHB up to 51.3% of its cell dry weight (CDW) from both glucose and xylose. Tryptone was identified as its best nitrogen source. PHB content and production reached 58.5% and 9.32 g/L, respectively, for an overall OPEFB sugar concentration of 45 g/L. These respectively reached 51.6% and 12.48 g/L for OPEFB hydrolysate containing 60 g/L sugar with a productivity of 0.260 g/L/h.


Assuntos
Arecaceae/metabolismo , Bacillus megaterium/metabolismo , Butiratos/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Meios de Cultura
19.
Nat Commun ; 4: 1662, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23575666

RESUMO

Toll-like receptor 4 (Tlr4) has a pivotal role in innate immune responses, and the transcription factor CCAAT/enhancer binding protein delta (C/EBPδ, Cebpd) is a Tlr4-induced gene. Here we identify a positive feedback loop in which C/EBPδ activates Tlr4 gene expression in macrophages and tumour cells. In addition, we discovered a negative feedback loop whereby the tumour suppressor FBXW7α (FBW7, Cdc4), whose gene expression is inhibited by C/EBPδ, targets C/EBPδ for degradation when C/EBPδ is phosphorylated by GSK-3ß. Consequently, FBXW7α suppresses Tlr4 expression and responses to the ligand lipopolysaccharide. FBXW7α depletion alone is sufficient to augment pro-inflammatory signalling in vivo. Moreover, as inflammatory pathways are known to modulate tumour biology, Cebpd null mammary tumours, which have reduced metastatic potential, show altered expression of inflammation-associated genes. Together, these findings reveal a role for C/EBPδ upstream of Tlr4 signalling and uncover a function for FBXW7α as an attenuator of inflammatory signalling.


Assuntos
Proteína delta de Ligação ao Facilitador CCAAT/fisiologia , Regulação para Baixo , Proteínas F-Box/fisiologia , Inflamação/fisiopatologia , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Animais , Linhagem Celular Tumoral , Proteínas F-Box/genética , Proteína 7 com Repetições F-Box-WD , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Inflamação/genética , Camundongos , RNA Mensageiro/genética , Ubiquitina-Proteína Ligases/genética
20.
J Microbiol Biotechnol ; 23(2): 246-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23412068

RESUMO

In this study, a loop-mediated isothermal amplification (LAMP) method to rapidly detect Staphylococcus aureus strains was developed and evaluated by extensively applying a large number of S. aureus isolates from clinical and food samples. Six primers were specially designed for recognizing eight distinct sequences on the species-specific femA gene of S. aureus. The detection limits were 100 fg DNA/tube and 10(4) CFU/ml. The LAMP assay was applied to 432 S. aureus strains isolated from 118 clinical and 314 food samples. Total detection rates for the LAMP and polymerase chain reaction assays were 98.4% (306/311) and 89.4% (278/311), respectively.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , Microbiologia de Alimentos/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Primers do DNA/genética , Humanos , Sensibilidade e Especificidade , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Temperatura , Fatores de Tempo
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