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1.
Plant J ; 116(6): 1766-1783, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37699038

RESUMEN

Brassinosteroids (BRs) are a class of steroid phytohormones that control various aspects of plant growth and development. Several transcriptional factors (TFs) have been suggested to play roles in BR signaling. However, their possible relationship remains largely unknown. Here, we identified a rice mutant dwarf and low-tillering 2 (dlt2) with altered plant architecture, increased grain width, and reduced BR sensitivity. DLT2 encodes a GIBBERELLIN INSENSITIVE (GAI)-REPRESSOR OF GAI (RGA)-SCARECROW (GRAS) TF that is mainly localized in the nucleus and has weak transcriptional activity. Our further genetic and biochemical analyses indicate that DLT2 interacts with two BR-signaling-related TFs, DLT and BRASSINAZOLE-RESISTANT 1, and probably modulates their transcriptional activity. These findings imply that DLT2 is implicated in a potentially transcriptional complex that mediates BR signaling and rice development and suggests that DLT2 could be a potential target for improving rice architecture and grain morphology. This work also sheds light on the role of rice GRAS members in regulating numerous developmental processes.


Asunto(s)
Brasinoesteroides , Oryza , Proteínas de Plantas/metabolismo , Transducción de Señal/genética , Grano Comestible/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
BMC Cancer ; 24(1): 288, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38439023

RESUMEN

BACKGROUND: Although HPV prophylactic vaccines can provide effective immune protection against high-risk HPV infection, studies have shown that the protective effect provided by them would decrease with the increased age of vaccination, and they are not recommended for those who are not in the appropriate age range for vaccination. Therefore, in those people who are not suitable for HPV prophylactic vaccines, it is worth considering establishing memory T-cell immunity to provide long-term immune surveillance and generate a rapid response against lesional cells to prevent tumorigenesis. METHODS: In this study, healthy mice were preimmunized with LM∆E6E7 and LI∆E6E7, the two Listeria-vectored cervical cancer vaccine candidate strains constructed previously by our laboratory, and then inoculated with tumor cells 40 d later. RESULTS: The results showed that preimmunization with LM∆E6E7 and LI∆E6E7 could establish protective memory T-cell immunity against tumor antigens in mice, which effectively eliminate tumor cells. 60% of mice preimmunized with vaccines did not develop tumors, and for the remaining mice, tumor growth was significantly inhibited. We found that preimmunization with vaccines may exert antitumor effects by promoting the enrichment of T cells at tumor site to exert specific immune responses, as well as inhibiting intratumoral angiogenesis and cell proliferation. CONCLUSION: Altogether, this study suggests that preimmunization with LM∆E6E7 and LI∆E6E7 can establish memory T-cell immunity against tumor antigens in vivo, which provides a viable plan for preventing tumorigenesis and inhibiting tumor progression.


Asunto(s)
Vacunas contra el Cáncer , Listeria , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Animales , Ratones , Femenino , Memoria Inmunológica , Células T de Memoria , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/prevención & control , Carcinogénesis , Transformación Celular Neoplásica , Neoplasias del Cuello Uterino/prevención & control , Antígenos de Neoplasias
3.
J Nat Prod ; 87(2): 388-395, 2024 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-38319739

RESUMEN

The bacillamides are a class of indole alkaloids produced by the Bacillus genus that possess significant antialgal activity. Incorporation of fluorine into the bacillamides was carried out using a precursor-directed biosynthesis approach, with 4-, 5-, and 6-fluorotryptophan added to growing cultures of Bacillus atrophaeus IMG-11. This yielded the corresponding fluorinated analogues of bacillamides A and C, in addition to new derivatives of the related metabolite N-acetyltryptamine, thus demonstrating a degree of plasticity in the bacillamide biosynthetic pathway. The bacillamide derivatives were tested for activity against bloom-forming algae, which revealed that fluorination could improve the antialgal activity of these compounds in a site-specific manner, with fluorination at the 6-position consistently resulting in improved activity.


Asunto(s)
Bacillus , Tiazoles , Triptaminas , Bacillus/metabolismo , Triptaminas/química , Tiazoles/química , Halogenación
4.
Bioorg Chem ; 142: 106974, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37984103

RESUMEN

Nicotinamide adenine dinucleotide (NAD+) serves as a critical cofactor in cellular metabolism and redox reactions. Bacterial pathways rely on NAD+ participation, where its stability and concentration govern essential homeostasis and functions. This review delves into the role and metabolic regulation of NAD+ in bacteria, highlighting its influence on physiology and virulence. Notably, we explore enzymes linked to NAD+ metabolism as antibacterial drug targets and vaccine candidates. Moreover, we scrutinize NAD+'s medical potential, offering insights for its application in biomedicine. This comprehensive assessment informs future research directions in the dynamic realm of NAD+ and its biomedical significance.


Asunto(s)
Bacterias , NAD , NAD/metabolismo , Oxidación-Reducción , Homeostasis , Bacterias/metabolismo
5.
Ecotoxicol Environ Saf ; 278: 116432, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38728947

RESUMEN

Cadmium (Cd) pollution is a serious global environmental problem, which requires a global concern and practical solutions. Microbial remediation has received widespread attention owing to advantages, such as environmental friendliness and soil amelioration. However, Cd toxicity also severely deteriorates the remediation performance of functional microorganisms. Analyzing the mechanism of bacterial resistance to Cd stress will be beneficial for the application of Cd remediation. In this study, the bacteria strain, up to 1400 mg/L Cd resistance, was employed and identified as Proteus mirabilis Ch8 (Ch8) through whole genome sequence analyses. The results indicated that the multiple pathways of immobilizing and detoxifying Cd maintained the growth of Ch8 under Cd stress, which also possessed high Cd extracellular adsorption. Firstly, the changes in surface morphology and functional groups of Ch8 cells were observed under different Cd conditions through SEM-EDS and FTIR analyses. Under 100 mg/L Cd, Ch8 cells exhibited aggregation and less flagella; the Cd biosorption of Ch8 was predominately by secreting exopolysaccharides (EPS) and no significant change of functional groups. Under 500 mg/L Cd, Ch8 were present irregular polymers on the cell surface, some cells with wrapping around; the Cd biosorption capacity exhibited outstanding effects (38.80 mg/g), which was mainly immobilizing Cd by secreting and interacting with EPS. Then, Ch8 also significantly enhanced the antioxidant enzyme activity and the antioxidant substance content under different Cd conditions. The activities of SOD and CAT, GSH content of Ch8 under 500 mg/L Cd were significantly increased by 245.47%, 179.52%, and 241.81%, compared to normal condition. Additionally, Ch8 significantly induced the expression of Acr A and Tol C (the resistance-nodulation-division (RND) efflux pump), and some antioxidant genes (SodB, SodC, and Tpx) to reduce Cd damage. In particular, the markedly higher expression levels of SodB under Cd stress. The mechanism of Ch8 lays a foundation for its application in solving soil remediation.


Asunto(s)
Cadmio , Proteus mirabilis , Contaminantes del Suelo , Cadmio/toxicidad , Contaminantes del Suelo/toxicidad , Biodegradación Ambiental
6.
Plant Physiol ; 190(1): 352-370, 2022 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-35748750

RESUMEN

The pollen wall is important for protecting the male gametophyte and for fertilization. The lipid components of the pollen wall are mainly synthesized and transported from the sporophytic tapetum. Although several factors related to lipid biosynthesis have been characterized, the molecular mechanisms underlying lipid biosynthesis during pollen development in rice (Oryza sativa L.) remain elusive. Here, we showed that mutation in the SWOLLEN TAPETUM AND STERILITY 1 (STS1) gene causes delayed tapetum degradation and aborted pollen wall formation in rice. STS1 encodes an endoplasmic reticulum (ER)-localized protein that contains domain of unknown function (DUF) 726 and exhibits lipase activity. Lipidomic and transcriptomic analyses showed that STS1 is involved in anther lipid homeostasis. Moreover, STS1 interacts with Polyketide Synthase 2 (OsPKS2) and Acyl-CoA Synthetase 12 (OsACOS12), two enzymes crucial in lipidic sporopollenin biosynthesis in pollen wall formation, suggesting a potentially lipidic metabolon for sporopollenin biosynthesis in rice. Collectively, our results indicate that STS1 is an important factor for lipid biosynthesis in reproduction, providing a target for the artificial control of male fertility in hybrid rice breeding and insight into the function of DUF726-containing protein in plants.


Asunto(s)
Infertilidad , Oryza , Flores , Regulación de la Expresión Génica de las Plantas , Infertilidad/metabolismo , Lípidos , Oryza/metabolismo , Fitomejoramiento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen
7.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37930836

RESUMEN

BACKGROUND: Pseudomonas aeruginosa is a significant clinical pathogen that poses a substantial threat due to its extensive drug resistance. The rapid and precise identification of this resistance is crucial for effective clinical treatment. Although matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used for antibiotic susceptibility differentiation of some bacteria in recent years, the genetic diversity of P. aeruginosa complicates population analysis. Rapid identification of antimicrobial resistance (AMR) in P. aeruginosa based on a large amount of MALDI-TOF-MS data has not yet been reported. In this study, we employed publicly available datasets for P. aeruginosa, which contain data on bacterial resistance and MALDI-TOF-MS spectra. We introduced a deep neural network model, synergized with a strategic sampling approach (SMOTEENN) to construct a predictive framework for AMR of three widely used antibiotics. RESULTS: The framework achieved area under the curve values of 90%, 85%, and 77% for Tobramycin, Cefepime, and Meropenem, respectively, surpassing conventional classifiers. Notably, random forest algorithm was used to assess the significance of features and post-hoc analysis was conducted on the top 10 features using Cohen's d. This analysis revealed moderate effect sizes (d = 0.5-0.8) in Tobramycin and Cefepime models. Finally, putative AMR biomarkers were identified in this study. CONCLUSIONS: This work presented an AMR prediction tool specifically designed for P. aeruginosa, which offers a hopeful pathway for clinical decision-making.


Asunto(s)
Pseudomonas aeruginosa , Tobramicina , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Pseudomonas aeruginosa/genética , Cefepima/farmacología , Factores de Tiempo , Tobramicina/farmacología
8.
Tohoku J Exp Med ; 260(2): 149-163, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-36927682

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is closely associated with low-grade chronic inflammation which is usually induced by intestinal dysbiosis. As ferulic acid (FA) has been proven effective at improving the intestinal integrity, we aimed to determine the effect of dietary FA on NAFLD development in high-fat dieted (HFD) mice, a well-established model of NAFLD. Male C57BL/6J mice were fed either a normal chow diet (ND) or HFD with or without FA (40 mg/kg) orally for 6 weeks. FA significantly alleviated lipid metabolism disorder and reduced liver inflammation in HFD mice (P < 0.05). As expected, FA improved the ileal intestinal integrity likely via the Nuclear factor E2-related factor 2 (Nrf2)/Heme oxygenase-1 (HO-1) signaling pathway. Importantly, we found that FA also relieved HFD-induced gut microbiota dysbiosis by inhibiting the growth of harmful bacteria such as Helicobacter and increased the abundance of many short-chain fatty acids (SCFAs)-producing bacteria (P < 0.05). Our data indicated that FA not only increased the colonic levels of SCFAs, but also maintained the colonic barrier integrity by up-regulating the expression of the epithelial tight junction protein. These data indicated that FA alleviated NAFLD by reducing circulating lipopolysaccharide levels. These effects may be due to improved proximal and distal intestinal barriers, which presumably mediated through the interaction of FA with the gut microbiota.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Masculino , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Disbiosis/complicaciones , Disbiosis/tratamiento farmacológico , Disbiosis/metabolismo , Ratones Endogámicos C57BL , Hígado/metabolismo , Inflamación/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Lípidos/farmacología
9.
Molecules ; 28(8)2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37110586

RESUMEN

Cordyceps has anti-cancer effects; however, the bioactive substance and its effect are still unclear. Polysaccharides extracted from Cordyceps sinensis, the fugus of Cordyceps, have been reported to have anti-cancer properties. Thus, we speculated that polysaccharides might be the key anti-tumor active ingredients of Cordyceps because of their larger molecular weight than that of polysaccharides in Cordyceps sinensis. In this study, we aimed to investigate the effects of wild Cordyceps polysaccharides on H22 liver cancer and the underlying mechanism. The structural characteristics of the polysaccharides of WCP were analyzed by high-performance liquid chromatography, high-performance gel-permeation chromatography, Fourier transform infrared spectrophotometry, and scanning electron microscopy. Additionally, H22 tumor-bearing BALB/c mice were used to explore the anti-tumor effect of WCP (100 and 300 mg/kg/d). The mechanism by WCP inhibited H22 tumors was uncovered by the TUNEL assay, flow cytometry, hematoxylin-eosin staining, quantitative reverse transcription-polymerase chain reaction, and Western blotting. Here, our results showed that WCP presented high purity with an average molecular weight of 2.1 × 106 Da and 2.19 × 104 Da. WCP was determined to be composed of mannose, glucose, and galactose. Notably, WCP could inhibit the proliferation of H22 tumors not only by improving immune function, but also by promoting the apoptosis of tumor cells, likely through the IL-10/STAT3/Bcl2 and Cyto-c/Caspase8/3 signaling pathways, in H22 tumor-bearing mice. Particularly, WCP had essentially no side effects compared to 5-FU, a common drug used in the treatment of liver cancer. In conclusion, WCP could be a potential anti-tumor product with strong regulatory effects in H22 liver cancer.


Asunto(s)
Antineoplásicos , Cordyceps , Neoplasias Hepáticas , Animales , Ratones , Cordyceps/química , Peso Molecular , Antineoplásicos/química , Polisacáridos/química , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología
10.
Plant J ; 108(2): 358-377, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34314535

RESUMEN

The plant pollen wall protects the male gametophyte from various biotic and abiotic stresses. The formation of a unique pollen wall structure and elaborate exine pattern is a well-organized process, which needs coordination between reproductive cells and the neighboring somatic cells. However, molecular mechanisms underlying this process remain largely unknown. Here, we report a rice male-sterile mutant (l94) that exhibits defective pollen exine patterning and abnormal tapetal cell development. MutMap and knockout analyses demonstrated that the causal gene encodes a type-G non-specific lipid transfer protein (OsLTPL94). Histological and cellular analyses established that OsLTPL94 is strongly expressed in the developing microspores and tapetal cells, and its protein is secreted to the plasma membrane. The l94 mutation impeded the secretory ability of OsLTPL94 protein. Further in vivo and in vitro investigations supported the hypothesis that ETERNAL TAPETUM 1 (EAT1), a basic helix-loop-helix transcription factor (bHLH TF), activated OsLTPL94 expression through direct binding to the E-box motif of the OsLTPL94 promoter, which was supported by the positive correlation between the expression of EAT1 and OsLTPL94 in two independent eat1 mutants. Our findings suggest that the secretory OsLTPL94 plays a key role in the coordinated development of tapetum and microspores with the regulation of EAT1.


Asunto(s)
Proteínas Portadoras/metabolismo , Oryza/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Polen/crecimiento & desarrollo , Proteínas Portadoras/genética , Elementos E-Box , Regulación de la Expresión Génica de las Plantas , Mutación , Oryza/genética , Oryza/metabolismo , Infertilidad Vegetal/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas
11.
Small ; 18(38): e2203035, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35988138

RESUMEN

Capacity degradation and destructive hazards are two major challenges for the operation of lithium-ion batteries at high temperatures. Although adding flame retardants or fire extinguishing agents can provide one-off self-protection in case of emergency overheating, it is desirable to directly regulate battery operation according to the temperature. Herein, smart self-protecting aqueous lithium-ion batteries are developed using thermos-responsive separators prepared through in situ polymerization on the hydrophilic separator. The thermos-responsive separator blocks the lithium ion transport channels at high temperature and reopens when the battery cools down; more importantly, this transition is reversible. The influence of lithium salts on the thermos-responsive behaviors of the hydrogels is investigated. Then suitable lithium salt (LiNO3 ) and concentration (1 m) are selected in the electrolyte to achieve self-protection without sacrificing battery performance. The shut-off temperature can be tuned from 30 to 80 °C by adjusting the hydrophilic and hydrophobic moiety ratio in the hydrogel for targeted applications. This self-protecting LiMn2 O4 /carbon coated LiTi2 (PO4 )3 (LMO/C-LTP) battery shows promise for smart energy storage devices with high safety and extended lifespan in case of high operating temperatures.

12.
Metabolomics ; 18(11): 93, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36378357

RESUMEN

INTRODUCTION: Previous reports revealed the role played by Salmonella PhoP-PhoQ system in virulence activation, antimicrobial tolerance and intracellular survival, the impact of PhoP-PhoQ on cell metabolism has been less extensively described. OBJECTIVES: The aim of this study is to address whether and how the PhoP-PhoQ system affects the cell metabolism of Salmonella. METHODS: We constructed a Salmonella phoP deletion mutant strain TT-81 (PhoP-OFF), a Salmonella PhoP constitutively expressed strain TT-82 (PhoP-ON) and a wild-type Salmonella PhoP strain TT-80 (PhoP-N), using P22-mediated generalized transduction or λ Red-mediated targeted mutagenesis. We then measured the in vitro growth kinetics of all test strains and determined their metabolomic and transcriptomic profiles using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) and RNA-seq technique, respectively. RESULTS: Low-Mg2+ conditions impaired the growth of the phoP deletion mutant strain TT-81 (PhoP-OFF) dramatically. 42 metabolites in the wild-type PhoP strain TT-80 (PhoP-N) and 28 metabolites in the PhoP constitutively expressed strain TT-82 (PhoP-ON) changed by the absence of phoP. In contrast, the level of 19 compounds in TT-80 (PhoP-N) changed comparing to the PhoP constitutively expressed strain TT-82 (PhoP-N). The mRNA level of 95 genes in TT-80 (PhoP-N) changed when phoP was disrupted, wherein 78 genes downregulated and 17 genes upregulated. 106 genes were determined to be differentially expressed between TT-81 (PhoP-OFF) and TT-82 (PhoP-ON). While only 16 genes were found to differentially expressed between TT-82 (PhoP-ON) and TT-80 (PhoP-N). CONCLUSION: Our findings confirmed the impact of PhoP-PhoQ system on lipopolysaccharide (LPS) modification, energy metabolism, and the biosynthesis or transport of amino acids. Most importantly, we demonstrated that the turnover of a given metabolite could respond differentially to the level of phoP. Taken together, the present study provided new insights into the adaptation of Salmonella to the host environment and helped to characterize the impact of the PhoP-PhoQ system on the cell metabolism.


Asunto(s)
Proteínas Bacterianas , Transcriptoma , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Transcriptoma/genética , Espectrometría de Masas en Tándem , Metabolómica , Cromatografía de Gases y Espectrometría de Masas , Salmonella/genética , Salmonella/metabolismo
13.
Exp Eye Res ; 220: 109111, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35569517

RESUMEN

PURPOSE: Thyroid hormones have a critical role in maintaining metabolic and physiological homeostasis. However, understanding of the possible effects of thyroid dysfunction on corneal homeostasis and the wound healing process is quite limited. To explore the influence of hypothyroidism on corneal homeostasis and the post-wound repair processes of the murine cornea. METHODS: A hypothyroidism model was established by total thyroidectomy (TThy) in C57BL/6J mice. On day 10 after TThy, hypothyroidism was confirmed via thyronine (T3 and T4) and thyroid-stimulating hormone serum levels. We further assessed changes in corneal thickness, corneal sensitivity, sub-basal nerve density, and the corneal expression of thyroid hormone receptors. A corneal epithelial abrasion model was established via mechanical removal of a central epithelium 2 mm in diameter. Wound closure and recruitment of inflammatory cells (neutrophils and γδ T-cells) were evaluated. RNA-sequencing and gene set enrichment analysis were performed in injured corneas after abrasion. The effect of local T3 administration on corneal wound healing in thyroidectomized mice was also observed. RESULTS: Compared with sham-operated control mice, the TThy-treated mice showed the following: (1) a significant decrease in corneal epithelial thickness, sensitivity to external stimuli, and sub-basal nerve density, as well as an alteration in thyroid hormone receptor expression in the steady state; (2) delayed corneal wound repair and enhanced inflammatory response after corneal abrasion; (3) down-regulation of actin-skeleton and DNA replication pathways and up-regulation of inflammation-associated pathways in abraded corneas; and (4) significant restoration of delayed corneal wound repair and inhibition of excessive inflammation following topical T3 administration. CONCLUSIONS: We conclude that deficient thyroid hormone secretion significantly affects corneal homeostasis and post-wound repair processes. Topical T3 administration might have a potential reversal effect on delayed corneal wound repair among hypothyroid individuals.


Asunto(s)
Lesiones de la Cornea , Epitelio Corneal , Hipotiroidismo , Animales , Córnea/metabolismo , Lesiones de la Cornea/metabolismo , Epitelio Corneal/metabolismo , Homeostasis , Hipotiroidismo/metabolismo , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Cicatrización de Heridas/fisiología
14.
Vet Res ; 53(1): 113, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36587206

RESUMEN

Listeriolysin O (LLO) is the main virulence protein of Listeria monocytogenes (LM), that helps LM escape lysosomes. We previously found that the cellular immune response elicited by L.ivanovii (LI) is weaker than that elicited by LM. We speculated that this may be related to the function of ivanolysin O (ILO). Here, we constructed hemolysin gene deletion strain, LIΔilo, and a modified strain, LIΔilo::hly, in which ilo was replaced by hly. Prokaryotic transcriptome sequencing was performed on LI, LIΔilo, and LIΔilo::hly. Transcriptome differences between the three strains were compared, and genes and pathways with significant differences between the three strains were analyzed. Prokaryotic transcriptome sequencing results revealed the relationship of ilo to the ribosome, quorum sensing, and phosphotransferase system (PTS) pathways, etc. LIΔilo exhibited attenuated biofilm formation ability compared to LI. Biofilm formation was significantly recovered or even increased after replenishing hly. After knocking out ilo, the relative expression levels of some virulence genes, including sigB, prfA, actA, smcL, and virR, were up-regulated compared to LI. After replenishing hly, these genes were down-regulated compared to LIΔilo. The trend and degree of such variation were not completely consistent when cultured in media containing only monosaccharides or disaccharides. The results confirmed that hemolysin is related to some important biological properties of Listeria, including biofilm formation and virulence gene expression levels. This is the first comprehensive study on ILO function at the transcriptomic level and the first evidence of a relationship between Listeria hemolysin and biofilm formation.


Asunto(s)
Listeria monocytogenes , Listeria , Animales , Listeria/genética , Listeria/metabolismo , Proteínas Hemolisinas/genética , Transcriptoma , Listeria monocytogenes/genética , Biopelículas , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
15.
BMC Microbiol ; 21(1): 194, 2021 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-34174835

RESUMEN

BACKGROUND: Serological test is helpful in confirming and tracking infectious diseases in large population with the advantage of fast and convenience. Using the specific epitope peptides identified from the whole antigen as the detection antigen is sensitive and relatively economical. The development of epitope peptide-based detection kits for COVID-19 patients requires comprehensive information about epitope peptides. But the data on B cell epitope of SARS-CoV-2 spike protein is still limited. More importantly, there is a lack of serological data on the peptides in the population. In this study, we aimed to identify the B cell epitope peptides of spike protein and detect the reactivity in serum samples, for further providing data support for their subsequent serological applications. RESULTS: Two B cell linear epitopes, P104 and P82, located in non-RBD region of SARS-CoV-2 S protein were identified by indirect ELISA screening of an overlapping peptide library of the S protein with COVID-19 patients' convalescent serum. And the peptides were verified by testing with 165 serum samples. P104 has not been reported previously; P82 is contained in peptide S21P2 reported before. The positive reaction rates of epitope peptides S14P5 and S21P2, the two non-RBD region epitopes identified by Poh et al., and P82 and P104 were 77.0%, 73.9%, 61.2% and 30.3%, respectively, for 165 convalescent sera, including 30 asymptomatic patients. Although P104 had the lowest positive rate for total patients (30.3%), it exhibited slight advantage for detection of asymptomatic infections (36.7%). Combination of epitopes significantly improved the positive reaction rate. Among all combination patterns, (S14P5 + S21P2 + P104) pattern exhibited the highest positive reaction rate for all patients (92.7%), as well as for asymptomatic infections (86.7%), confirming the feasibility of P104 as supplementary antigen for serological detection. In addition, we analyzed the correlation between epitopes with neutralizing antibody, but only S14P5 had a medium positive correlation with neutralizing antibody titre (rs = 0.510, P < 0.01). CONCLUSION: Our research proved that epitopes on non-RBD region are of value in serological detection especially when combination more than one epitope, thus providing serological reaction information about the four epitopes, which has valuable references for their usage.


Asunto(s)
Prueba Serológica para COVID-19/métodos , COVID-19 , Ensayo de Inmunoadsorción Enzimática/métodos , Epítopos de Linfocito B , Glicoproteína de la Espiga del Coronavirus/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/diagnóstico , COVID-19/inmunología , COVID-19/virología , Niño , Preescolar , Epítopos de Linfocito B/química , Epítopos de Linfocito B/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptidos/química , Péptidos/inmunología , Dominios Proteicos , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven
16.
Clin Lab ; 67(10)2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34655188

RESUMEN

BACKGROUND: Para-Bombay phenotype is rare in ABO blood group. We describe FUT1 mutations in a Chinese woman with the para-Bombay phenotype, including her familial inheritance. METHODS: ABO grouping, H antigen detection, absorptionelution test, salivary antigen substance detection, deter-mination of titer of ABH antibody, ABO genotyping, gene sequencing (FUT1,2), blood transfusion compatibility test, and pedigree investigation were performed. RESULTS: The patient was confirmed as group A1 para-Bombay phenotype (Amh) in her family's investigation, revealing her FUT1 gene had c.658C>T (p.Arg220Cys) homozygous mutation and FUT2 gene had c.357C>T homozygous mutation. The patient was provided an appropriate transfusion solution. CONCLUSIONS: A combination of using classical serological methods, gene sequencing methods and pedigree investigation methods can effectively analyze the genetic inheritance of patients with para-Bombay phenotype, increasing their choices of blood transfusion.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Fucosiltransferasas , Sistema del Grupo Sanguíneo ABO/genética , Alelos , Femenino , Fucosiltransferasas/genética , Genotipo , Humanos , Mutación , Linaje , Fenotipo , Galactósido 2-alfa-L-Fucosiltransferasa
17.
Clin Lab ; 67(12)2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34910420

RESUMEN

BACKGROUND: The Para-Bombay phenotype is characterized by H antigen partially or totally deficient on red blood cells and the presence of ABH substances in body fluids. METHODS: A patient with discrepant results in forward and reverse ABO phenotyping was further investigated by serological and molecular methods. RESULTS: Ortho gel and tube results showed weak A antigen expression and weak antibody reacting with A and B cells. Absorption-elution assay detected B antigen, and saliva test confirmed substances H were present. The patient was confirmed as A102B101 and Le(a+b+) phenotype. CONCLUSIONS: These findings suggest that the case is AB Para-Bombay Phenotype (secretor).


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Eritrocitos , Sistema del Grupo Sanguíneo ABO/genética , Humanos , Fenotipo
18.
BMC Health Serv Res ; 21(1): 959, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34517862

RESUMEN

BACKGROUND: The current 2019 coronavirus disease (COVID-19) pandemic is hitting citizen's life and health like never before, with its significant loss to human life and a huge economic toll. In this case, the fever clinics (FCs) were still preserved as one of the most effective control measures in China, but this work is based on experience and lacks scientific and effective guidance. Here, we use travel time to link facilities and populations at risk of COVID-19 and identify the dynamic allocation of patients' medical needs, and then propose the optimized allocation scheme of FCs. METHODS: We selected Shenzhen, China, to collect geospatial resources of epidemic communities (ECs) and FCs to determine the ECs' cumulative opportunities of visiting FCs, as well as evaluate the rationality of medical resources in current ECs. Also, we use the Location Set Covering Problem (LSCP) model to optimize the allocation of FCs and evaluate efficiency. RESULTS: Firstly, we divide the current ECs into 3 groups based on travel time and cumulative opportunities of visiting FCs within 30 min: Low-need communities (22.06%), medium-need communities (59.8%), and high-need communities (18.14%) with 0,1-2 and no less than 3 opportunities of visiting FCs. Besides, our work proposes two allocation schemes of fever clinics through the LSCP model. Among which, selecting secondary and above hospitals as an alternative in Scheme 1, will increase the coverage rate of hospitals in medium-need and high-need communities from 59.8% to 80.88%. In Scheme 2, selecting primary and above hospitals as an alternative will increase the coverage rate of hospitals in medium-need and high-need communities to 85.29%, with the average travel time reducing from 22.42 min to 17.94 min. CONCLUSIONS: The optimized allocation scheme can achieve two objectives: a. equal access to medical services for different types of communities has improved while reducing the overutilization of high-quality medical resources. b. the travel time for medical treatment in the community has reduced, thus improving medical accessibility. On this basis, during the early screening in prevention and control of the outbreak, the specific suggestions for implementation in developing and less developed countries are made.


Asunto(s)
COVID-19 , China/epidemiología , Investigación Empírica , Humanos , Pandemias , SARS-CoV-2
19.
J Cell Physiol ; 235(5): 4508-4519, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31625162

RESUMEN

Haspin (Haploid Germ Cell-Specific Nuclear Protein Kinase) is a serine/threonine kinase pertinent to normal mitosis progression and mitotic phosphorylation of histone H3 at threonine 3 in mammalian cells. Different classes of small molecule inhibitors of haspin have been developed and utilized to investigate its mitotic functions. We report herein that applying haspin inhibitor CHR-6494 or 5-ITu at the G1/S boundary could delay mitotic entry in synchronized HeLa and U2OS cells, respectively, following an extended G2 or the S phase. Moreover, late application of haspin inhibitors at S/G2 boundary is sufficient to delay mitotic onset in both cell lines, thereby, indicating a direct effect of haspin on G2/M transition. A prolonged interphase duration is also observed with knockdown of haspin expression in synchronized and asynchronous cells. These results suggest that haspin can regulate cell cycle progression at multiple stages at both interphase and mitosis.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Indazoles/farmacología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Piridazinas/farmacología , Tubercidina/análogos & derivados , Línea Celular Tumoral , Inhibidores Enzimáticos/farmacología , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Mitosis , Proteínas Serina-Treonina Quinasas/genética , Tubercidina/farmacología
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 1-6, 2020 Jan.
Artículo en Zh | MEDLINE | ID: mdl-31950781

RESUMEN

OBJECTIVE: To construct a recombinant Listeria ivanovii (LI) strain that expressed Mycobacterium tuberculosis (MTB) specific antigen protein as a novel multistage tuberculosis (TB) vaccine candidate, and evaluate the biosafety and immunogenicity in mouse model. METHODS: T cell epitopes of four genes related to different stages of MTB infection were fused in series to form an antigen gene, i.e. the multistage antigen gene (named msv). Then msv was inserted into the targeting plasmid that contained LI homologous sequences. Recombinant LI strain was obtained by transfecting LI with targeting plasmid and screening the recombinant LI strain that carried msv in the genome after series of homologous gene recombination processes. The growth rate of the recombinant LI strain in vitro was observed and the expression of target protein was verified by Western blot. The 50% lethal dose (LD 50) of the recombinant strain to C57BL/6 mice was measured. Mice were intravenously inoculated with vaccine candidate in dose of 0.1×LD 50.The serum alanine aminotransferase (ALT) levels, bacterial load in organs, and organ pathological sections before and 1, 2, 3, 5, 7, 14 d after vaccination were used to evaluate the safety of vaccine candidate strain. To analyze the immunogenicity of vaccine candidate strain, mice were intravenously inoculated with LI- msv, LI, and NS respectively. Nine days post immunization, the spleens were isolated under sterile conditions and splenocytes were collected and stimulated. Lyphocytes which secret specific cytokines, interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-2 were analyzed by flow cytometry. RESULTS: A recombinant strain named LI- msv which was capable of expressing the multistage TB antigen protein was successfully constructed. The LD 50 value of LI- msv for C57BL/6 mice (i.v.) was 3.3×10 8 CFU. After intravenously immunized the mice, this strain mainly multiplied in the liver and spleen, and was cleared at 7 d post innoculation. Such infection process caused transient pathological damages of the liver and spleen. Results of flow cytometry showed specific IFN-γ + CD4 + and IFN-γ + CD8 +T lymphocytes were successfully induced in LI -msv immunized mice spleen lymphocytes. The frequency of IFN-γ positive CD4 + and CD8 +T cells was significantly higher than those of vector control group and NS control group ( P<0.005). Additionally, the frequency of specific TNF-α + CD4 + T cell in LI -msv immunized group was significantly higher than that of vector control ( P<0.01) and NS control group ( P<0.005), and TNF-α + CD8 + T cell frequency obviously increased than NS control group ( P<0.005). CONCLUSIONS: A novel multistage TB vaccine candidate expressing TB multistage antigen based on LI was successfully constructed. This vaccine candidate is safe and can induce specific cellular immune response to some extent. It is promising to be further studied as a candidate vaccine against tuberculosis.


Asunto(s)
Antígenos Bacterianos , Listeria , Mycobacterium tuberculosis , Vacunas contra la Tuberculosis , Tuberculosis/prevención & control , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Linfocitos T CD4-Positivos/inmunología , Inmunidad Celular/inmunología , Listeria/genética , Ratones , Ratones Endogámicos C57BL , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Tuberculosis/inmunología , Vacunas contra la Tuberculosis/genética , Vacunas contra la Tuberculosis/normas
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